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Sample records for repeated studies show

  1. Repeatability study of replicate crash tests: A signal analysis approach.

    Science.gov (United States)

    Seppi, Jeremy; Toczyski, Jacek; Crandall, Jeff R; Kerrigan, Jason

    2017-10-03

    To provide an objective basis on which to evaluate the repeatability of vehicle crash test methods, a recently developed signal analysis method was used to evaluate correlation of sensor time history data between replicate vehicle crash tests. The goal of this study was to evaluate the repeatability of rollover crash tests performed with the Dynamic Rollover Test System (DRoTS) relative to other vehicle crash test methods. Test data from DRoTS tests, deceleration rollover sled (DRS) tests, frontal crash tests, frontal offset crash tests, small overlap crash tests, small overlap impact (SOI) crash tests, and oblique crash tests were obtained from the literature and publicly available databases (the NHTSA vehicle database and the Insurance Institute for Highway Safety TechData) to examine crash test repeatability. Signal analysis of the DRoTS tests showed that force and deformation time histories had good to excellent repeatability, whereas vehicle kinematics showed only fair repeatability due to the vehicle mounting method for one pair of tests and slightly dissimilar mass properties (2.2%) in a second pair of tests. Relative to the DRS, the DRoTS tests showed very similar or higher levels of repeatability in nearly all vehicle kinematic data signals with the exception of global X' (road direction of travel) velocity and displacement due to the functionality of the DRoTS fixture. Based on the average overall scoring metric of the dominant acceleration, DRoTS was found to be as repeatable as all other crash tests analyzed. Vertical force measures showed good repeatability and were on par with frontal crash barrier forces. Dynamic deformation measures showed good to excellent repeatability as opposed to poor repeatability seen in SOI and oblique deformation measures. Using the signal analysis method as outlined in this article, the DRoTS was shown to have the same or better repeatability of crash test methods used in government regulatory and consumer evaluation test

  2. A novel rat genomic simple repeat DNA with RNA-homology shows triplex (H-DNA)-like structure and tissue-specific RNA expression

    International Nuclear Information System (INIS)

    Dey, Indranil; Rath, Pramod C.

    2005-01-01

    Mammalian genome contains a wide variety of repetitive DNA sequences of relatively unknown function. We report a novel 227 bp simple repeat DNA (3.3 DNA) with a d {(GA) 7 A (AG) 7 } dinucleotide mirror repeat from the rat (Rattus norvegicus) genome. 3.3 DNA showed 75-85% homology with several eukaryotic mRNAs due to (GA/CU) n dinucleotide repeats by nBlast search and a dispersed distribution in the rat genome by Southern blot hybridization with [ 32 P]3.3 DNA. The d {(GA) 7 A (AG) 7 } mirror repeat formed a triplex (H-DNA)-like structure in vitro. Two large RNAs of 9.1 and 7.5 kb were detected by [ 32 P]3.3 DNA in rat brain by Northern blot hybridization indicating expression of such simple sequence repeats at RNA level in vivo. Further, several cDNAs were isolated from a rat cDNA library by [ 32 P]3.3 DNA probe. Three such cDNAs showed tissue-specific RNA expression in rat. pRT 4.1 cDNA showed strong expression of a 2.39 kb RNA in brain and spleen, pRT 5.5 cDNA showed strong expression of a 2.8 kb RNA in brain and a 3.9 kb RNA in lungs, and pRT 11.4 cDNA showed weak expression of a 2.4 kb RNA in lungs. Thus, genomic simple sequence repeats containing d (GA/CT) n dinucleotides are transcriptionally expressed and regulated in rat tissues. Such d (GA/CT) n dinucleotide repeats may form structural elements (e.g., triplex) which may be sites for functional regulation of genomic coding sequences as well as RNAs. This may be a general function of such transcriptionally active simple sequence repeats widely dispersed in mammalian genome

  3. Corticosterone stress response shows long-term repeatability and links to personality in free-living Nazca boobies.

    Science.gov (United States)

    Grace, Jacquelyn K; Anderson, David J

    2014-11-01

    The concept of "coping styles", or consistently different responses to stressors, is of broad interest in behavioral ecology and biomedicine. Two critical predictions of this concept are individual consistency of neurophysiological and behavioral responses (relative to population variability) and a negative relationship between aggression/proactivity and hypothalamic-pituitary-adrenal axis reactivity. Recent studies failed to provide strong support for these predictions, especially outside of strictly controlled conditions, and long-term measures to test the first prediction are rare. Here, we demonstrate individual repeatability across 2-3years of maximum circulating corticosterone concentration [CORT] and area under the [CORT] response curve (AUCI) during a standard capture-restraint test in wild, free-living adult Nazca boobies (Sula granti). We also show that the stress response predicts the personality traits aggression and anxiety in these birds (measured in the wild); however, the strength of these results was weak. Maximum [CORT] and AUCI showed higher repeatability between years than baseline [CORT]. After controlling breeding status, sex, mass, date sampled, and their interactions, baseline [CORT] was most closely related to personality traits, followed by AUCI, and then maximum [CORT]. The direction of these relationships depended on whether the testing context was social or non-social. [CORT] parameters had little to no relationship with cross-context plasticity in personality traits. Our results generally affirm two critical predictions of coping styles, but match the emerging trend that these relationships are weak in the wild, and may depend on testing context. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Serum iron, ferritin, transferrin and haptoglobin concentration variations during repeated show jumping competition in horse

    Directory of Open Access Journals (Sweden)

    Anna Assenza

    2016-01-01

    Full Text Available Modifications of the iron profile in athlete horses during two international three star (*** show jumping competitions performed in two consecutive weekends were evaluated. Serum iron, ferritin, transferrin, and haptoglobin were assessed in 12 well-trained Italian Saddle horses. Blood samplings were performed before the first day of competition (R1, within 10 min from the end of each competition (J1, J2 and on the day after competition (R2. The same plan was followed during the second weekend (J3, J4 and R3. One-way repeated measures analysis of variance (ANOVA was applied on obtained data, and a significant effect of exercise (P < 0.05 on all studied indices was found. These results suggest that serum iron, transferrin, ferritin and haptoglobin are responsive to intense exercise and could be considered important indicators that may give important information about the horse’s performance.

  5. Hysteresis of magnetostructural transitions: Repeatable and non-repeatable processes

    Science.gov (United States)

    Provenzano, Virgil; Della Torre, Edward; Bennett, Lawrence H.; ElBidweihy, Hatem

    2014-02-01

    The Gd5Ge2Si2 alloy and the off-stoichiometric Ni50Mn35In15 Heusler alloy belong to a special class of metallic materials that exhibit first-order magnetostructural transitions near room temperature. The magnetic properties of this class of materials have been extensively studied due to their interesting magnetic behavior and their potential for a number of technological applications such as refrigerants for near-room-temperature magnetic refrigeration. The thermally driven first-order transitions in these materials can be field-induced in the reverse order by applying a strong enough field. The field-induced transitions are typically accompanied by the presence of large magnetic hysteresis, the characteristics of which are a complicated function of temperature, field, and magneto-thermal history. In this study we show that the virgin curve, the major loop, and sequentially measured MH loops are the results of both repeatable and non-repeatable processes, in which the starting magnetostructural state, prior to the cycling of field, plays a major role. Using the Gd5Ge2Si2 and Ni50Mn35In15 alloys, as model materials, we show that a starting single phase state results in fully repeatable processes and large magnetic hysteresis, whereas a mixed phase starting state results in non-repeatable processes and smaller hysteresis.

  6. Hysteresis of magnetostructural transitions: Repeatable and non-repeatable processes

    International Nuclear Information System (INIS)

    Provenzano, Virgil; Della Torre, Edward; Bennett, Lawrence H.; ElBidweihy, Hatem

    2014-01-01

    The Gd 5 Ge 2 Si 2 alloy and the off-stoichiometric Ni 50 Mn 35 In 15 Heusler alloy belong to a special class of metallic materials that exhibit first-order magnetostructural transitions near room temperature. The magnetic properties of this class of materials have been extensively studied due to their interesting magnetic behavior and their potential for a number of technological applications such as refrigerants for near-room-temperature magnetic refrigeration. The thermally driven first-order transitions in these materials can be field-induced in the reverse order by applying a strong enough field. The field-induced transitions are typically accompanied by the presence of large magnetic hysteresis, the characteristics of which are a complicated function of temperature, field, and magneto-thermal history. In this study we show that the virgin curve, the major loop, and sequentially measured MH loops are the results of both repeatable and non-repeatable processes, in which the starting magnetostructural state, prior to the cycling of field, plays a major role. Using the Gd 5 Ge 2 Si 2 and Ni 50 Mn 35 In 15 alloys, as model materials, we show that a starting single phase state results in fully repeatable processes and large magnetic hysteresis, whereas a mixed phase starting state results in non-repeatable processes and smaller hysteresis

  7. Methods for analysing cardiovascular studies with repeated measures

    NARCIS (Netherlands)

    Cleophas, T. J.; Zwinderman, A. H.; van Ouwerkerk, B. M.

    2009-01-01

    Background. Repeated measurements in a single subject are generally more similar than unrepeated measurements in different subjects. Unrepeated analyses of repeated data cause underestimation of the treatment effects. Objective. To review methods adequate for the analysis of cardiovascular studies

  8. Quantum repeated games revisited

    International Nuclear Information System (INIS)

    Frąckiewicz, Piotr

    2012-01-01

    We present a scheme for playing quantum repeated 2 × 2 games based on Marinatto and Weber’s approach to quantum games. As a potential application, we study the twice repeated Prisoner’s Dilemma game. We show that results not available in the classical game can be obtained when the game is played in the quantum way. Before we present our idea, we comment on the previous scheme of playing quantum repeated games proposed by Iqbal and Toor. We point out the drawbacks that make their results unacceptable. (paper)

  9. Repeating and non-repeating fast radio bursts from binary neutron star mergers

    Science.gov (United States)

    Yamasaki, Shotaro; Totani, Tomonori; Kiuchi, Kenta

    2018-04-01

    Most fast radio bursts (FRB) do not show evidence of repetition, and such non-repeating FRBs may be produced at the time of a merger of binary neutron stars (BNS), provided that the BNS merger rate is close to the high end of the currently possible range. However, the merger environment is polluted by dynamical ejecta, which may prohibit the radio signal from propagating. We examine this by using a general-relativistic simulation of a BNS merger, and show that the ejecta appears about 1 ms after the rotation speed of the merged star becomes the maximum. Therefore there is a time window in which an FRB signal can reach outside, and the short duration of non-repeating FRBs can be explained by screening after ejecta formation. A fraction of BNS mergers may leave a rapidly rotating and stable neutron star, and such objects may be the origin of repeating FRBs like FRB 121102. We show that a merger remnant would appear as a repeating FRB on a time scale of ˜1-10 yr, and expected properties are consistent with the observations of FRB 121102. We construct an FRB rate evolution model that includes these two populations of repeating and non-repeating FRBs from BNS mergers, and show that the detection rate of repeating FRBs relative to non-repeating ones rapidly increases with improving search sensitivity. This may explain why only the repeating FRB 121102 was discovered by the most sensitive FRB search with Arecibo. Several predictions are made, including the appearance of a repeating FRB 1-10 yr after a BNS merger that is localized by gravitational waves and subsequent electromagnetic radiation.

  10. Expansion of protein domain repeats.

    Directory of Open Access Journals (Sweden)

    Asa K Björklund

    2006-08-01

    Full Text Available Many proteins, especially in eukaryotes, contain tandem repeats of several domains from the same family. These repeats have a variety of binding properties and are involved in protein-protein interactions as well as binding to other ligands such as DNA and RNA. The rapid expansion of protein domain repeats is assumed to have evolved through internal tandem duplications. However, the exact mechanisms behind these tandem duplications are not well-understood. Here, we have studied the evolution, function, protein structure, gene structure, and phylogenetic distribution of domain repeats. For this purpose we have assigned Pfam-A domain families to 24 proteomes with more sensitive domain assignments in the repeat regions. These assignments confirmed previous findings that eukaryotes, and in particular vertebrates, contain a much higher fraction of proteins with repeats compared with prokaryotes. The internal sequence similarity in each protein revealed that the domain repeats are often expanded through duplications of several domains at a time, while the duplication of one domain is less common. Many of the repeats appear to have been duplicated in the middle of the repeat region. This is in strong contrast to the evolution of other proteins that mainly works through additions of single domains at either terminus. Further, we found that some domain families show distinct duplication patterns, e.g., nebulin domains have mainly been expanded with a unit of seven domains at a time, while duplications of other domain families involve varying numbers of domains. Finally, no common mechanism for the expansion of all repeats could be detected. We found that the duplication patterns show no dependence on the size of the domains. Further, repeat expansion in some families can possibly be explained by shuffling of exons. However, exon shuffling could not have created all repeats.

  11. A study on radiographic repeat rate data of several hospitals in Jeddah

    International Nuclear Information System (INIS)

    Al-Malki, M.A.; Abulfaraj, W.H.; Bhuiyan, S.I.; Kinsara, A.A.

    2003-01-01

    Radiographic repeat rate data in diagnostic radiology in King Fahad Hospital (KFH), King Abdulaziz Hospital (KAH), and Maternity and Children Hospital (MCH) in Jeddah, Saudi Arabia, have been studied. The study provided valuable information to suggest preventive measures to reduce repeats. The variables included in the study are exposure techniques, examination types, total number of films used, number of films repeated, the film sizes, gender, the age groups of the patients, and reason for repetition. The total number of examinations in all three hospitals is 6001 using 8887 films on 5412 patients. The average repeat rate was 7.93%, where the individual hospital repeat rates were 9.57% in the MCH, 7.84% in KAH and 7.44% in KFH. The repeat rate for children and infants was found to be undesirable. The quality assurance (QA) programme can effectively reduce the unnecessary exposure and can identify the cause of the exposure. The overexposure, underexposure and position fault were the foremost contributors for repeats and constitute 32.91%, 28.94% and 22.98% of the total respectively. The QA study identified that human error and equipment malfunction are the major contributors to these causes of repeats. The highest repetition rate was for pelvis, 13.64%, followed by skull, 11.59%, and abdomen, 10.41%. It is estimated that the total area of wasted film in all three hospitals is 74.3 m 2 . As per the average repeat rate, the cost of repeat films in the entire kingdom per year has been projected to be about US$1.82 million (SR 6.83 million) in the government hospitals only. Based on the findings of this study a set of recommendations have been prescribed for the radiology department to reduce the repeat rate and to improve the safety culture. (author)

  12. A study on radiographic repeat rate data of several hospitals in Jeddah

    Energy Technology Data Exchange (ETDEWEB)

    Al-Malki, M.A.; Abulfaraj, W.H.; Bhuiyan, S.I.; Kinsara, A.A

    2003-07-01

    Radiographic repeat rate data in diagnostic radiology in King Fahad Hospital (KFH), King Abdulaziz Hospital (KAH), and Maternity and Children Hospital (MCH) in Jeddah, Saudi Arabia, have been studied. The study provided valuable information to suggest preventive measures to reduce repeats. The variables included in the study are exposure techniques, examination types, total number of films used, number of films repeated, the film sizes, gender, the age groups of the patients, and reason for repetition. The total number of examinations in all three hospitals is 6001 using 8887 films on 5412 patients. The average repeat rate was 7.93%, where the individual hospital repeat rates were 9.57% in the MCH, 7.84% in KAH and 7.44% in KFH. The repeat rate for children and infants was found to be undesirable. The quality assurance (QA) programme can effectively reduce the unnecessary exposure and can identify the cause of the exposure. The overexposure, underexposure and position fault were the foremost contributors for repeats and constitute 32.91%, 28.94% and 22.98% of the total respectively. The QA study identified that human error and equipment malfunction are the major contributors to these causes of repeats. The highest repetition rate was for pelvis, 13.64%, followed by skull, 11.59%, and abdomen, 10.41%. It is estimated that the total area of wasted film in all three hospitals is 74.3 m{sup 2}. As per the average repeat rate, the cost of repeat films in the entire kingdom per year has been projected to be about US$1.82 million (SR 6.83 million) in the government hospitals only. Based on the findings of this study a set of recommendations have been prescribed for the radiology department to reduce the repeat rate and to improve the safety culture. (author)

  13. Repeated DNA sequences in fungi

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, S K

    1974-11-01

    Several fungal species, representatives of all broad groups like basidiomycetes, ascomycetes and phycomycetes, were examined for the nature of repeated DNA sequences by DNA:DNA reassociation studies using hydroxyapatite chromatography. All of the fungal species tested contained 10 to 20 percent repeated DNA sequences. There are approximately 100 to 110 copies of repeated DNA sequences of approximately 4 x 10/sup 7/ daltons piece size of each. Repeated DNA sequence homoduplexes showed on average 5/sup 0/C difference of T/sub e/50 (temperature at which 50 percent duplexes dissociate) values from the corresponding homoduplexes of unfractionated whole DNA. It is suggested that a part of repetitive sequences in fungi constitutes mitochondrial DNA and a part of it constitutes nuclear DNA. (auth)

  14. t2prhd: a tool to study the patterns of repeat evolution

    Directory of Open Access Journals (Sweden)

    Pénzes Zsolt

    2008-01-01

    Full Text Available Abstract Background The models developed to characterize the evolution of multigene families (such as the birth-and-death and the concerted models have also been applied on the level of sequence repeats inside a gene/protein. Phylogenetic reconstruction is the method of choice to study the evolution of gene families and also sequence repeats in the light of these models. The characterization of the gene family evolution in view of the evolutionary models is done by the evaluation of the clustering of the sequences with the originating loci in mind. As the locus represents positional information, it is straightforward that in the case of the repeats the exact position in the sequence should be used, as the simple numbering according to repeat order can be misleading. Results We have developed a novel rapid visual approach to study repeat evolution, that takes into account the exact repeat position in a sequence. The "pairwise repeat homology diagram" visualizes sequence repeats detected by a profile HMM in a pair of sequences and highlights their homology relations inferred by a phylogenetic tree. The method is implemented in a Perl script (t2prhd available for downloading at http://t2prhd.sourceforge.net and is also accessible as an online tool at http://t2prhd.brc.hu. The power of the method is demonstrated on the EGF-like and fibronectin-III-like (Fn-III domain repeats of three selected mammalian Tenascin sequences. Conclusion Although pairwise repeat homology diagrams do not carry all the information provided by the phylogenetic tree, they allow a rapid and intuitive assessment of repeat evolution. We believe, that t2prhd is a helpful tool with which to study the pattern of repeat evolution. This method can be particularly useful in cases of large datasets (such as large gene families, as the command line interface makes it possible to automate the generation of pairwise repeat homology diagrams with the aid of scripts.

  15. Reduction and technical simplification of testing protocol for walking based on repeatability analyses: An Interreg IVa pilot study

    Directory of Open Access Journals (Sweden)

    Nejc Sarabon

    2010-12-01

    Full Text Available The aim of this study was to define the most appropriate gait measurement protocols to be used in our future studies in the Mobility in Ageing project. A group of young healthy volunteers took part in the study. Each subject carried out a 10-metre walking test at five different speeds (preferred, very slow, very fast, slow, and fast. Each walking speed was repeated three times, making a total of 15 trials which were carried out in a random order. Each trial was simultaneously analysed by three observers using three different technical approaches: a stop watch, photo cells and electronic kinematic dress. In analysing the repeatability of the trials, the results showed that of the five self-selected walking speeds, three of them (preferred, very fast, and very slow had a significantly higher repeatability of the average walking velocity, step length and cadence than the other two speeds. Additionally, the data showed that one of the three technical methods for gait assessment has better metric characteristics than the other two. In conclusion, based on repeatability, technical and organizational simplification, this study helped us to successfully define a simple and reliable walking test to be used in the main study of the project.

  16. All-photonic quantum repeaters

    Science.gov (United States)

    Azuma, Koji; Tamaki, Kiyoshi; Lo, Hoi-Kwong

    2015-01-01

    Quantum communication holds promise for unconditionally secure transmission of secret messages and faithful transfer of unknown quantum states. Photons appear to be the medium of choice for quantum communication. Owing to photon losses, robust quantum communication over long lossy channels requires quantum repeaters. It is widely believed that a necessary and highly demanding requirement for quantum repeaters is the existence of matter quantum memories. Here we show that such a requirement is, in fact, unnecessary by introducing the concept of all-photonic quantum repeaters based on flying qubits. In particular, we present a protocol based on photonic cluster-state machine guns and a loss-tolerant measurement equipped with local high-speed active feedforwards. We show that, with such all-photonic quantum repeaters, the communication efficiency scales polynomially with the channel distance. Our result paves a new route towards quantum repeaters with efficient single-photon sources rather than matter quantum memories. PMID:25873153

  17. Repeat film analysis and its implications for quality assurance in dental radiology: An institutional case study

    Directory of Open Access Journals (Sweden)

    Shruthi Acharya

    2015-01-01

    Full Text Available Context: The goal of any radiologist is to produce the highest quality diagnostic radiographs, while keeping patient exposure as low as reasonably achievable (ALARA. Aims: The aim of this study was to describe the reasons for radiograph rejections through a repeat film analysis in an Indian dental school. Settings and Design: An observational study conducted in the Department of Oral Medicine and Radiology, Manipal College of Dental Sciences, Manipal. Materials and Methods: During a 6-month study period, a total of 9,495 intra-oral radiographs and 2339 extraoral radiographs taken in the Radiology Department were subjected to repeat film analysis. Statistical Analysis Used: SPSS Version 16. Descriptive analysis used. Results: The results showed that the repeat rates were 7.1% and 5.86% for intraoral and extraoral radiographs, respectively. Among the causes for errors reported, positioning error (38.7% was the most common, followed by improper angulations (26.1%, and improper film placement (11.2% for intra-oral radiographs. The study found that the maximum frequency of repeats among extraoral radiographs was for panoramic radiographs (49% followed by lateral cephalogram (33%, and paranasal sinus view (14%. It was also observed that repeat rate of intraoral radiographs was highest for internees (44.7%, and undergraduate students (28.2%. Conclusions: The study pointed to a need for more targeted interventions to achieve the goal of keeping patient exposure ALARA in a dental school setting.

  18. The Outcome of Repeated Mid Urethral Sling in SUI Treatment after Vaginal Excisions of Primary Failed Sling: Preliminary Study

    Directory of Open Access Journals (Sweden)

    Jacek Kociszewski

    2016-01-01

    Full Text Available Mid urethral sling is the standard in SUI treatment. Nevertheless, the risk of reoperation reaches 9%. There is no consensus as to the best treatment option for complications. A question is raised: what is the optimal way to achieve the best result in patients after primary failure? The aim of the study was to evaluate the outcomes of repeat MUS surgery in patients after excision of the sling with recurrent SUI. We compared its effectiveness with uncomplicated cases treated with TVT. 27 patients who underwent the repeated MUS and 50 consecutive patients after primary TVT were enrolled in the study. After 6 months, we have found that 24 (88.46% patients from repeat sling group and 48 (96% patients after primary sling were dry (1-hour pad test, 2 g or less. The difference between groups was not significant. We showed statistically significant improvement of quality of life in both groups. In conclusion, we showed that repeated sling after MUS excision is almost as effective as primary MUS. We postulate that sling excision and repeated MUS may be the best option for persistent SUI and/or complications after MUS procedures. Further multicenter observations are ongoing as to provide results on bigger group of cases.

  19. Repeat profile analysis in an x-ray department

    International Nuclear Information System (INIS)

    Bassey, C.E.; Ojo, O.O.; Akpabio, I.

    1991-01-01

    The repeat profile of an x-ray department in a developing country was analysed monthly between July 1989 and June 1990. Results showed an average repeat rate of 3.7% for the period of study. The main causes of film repetition were: equipment fault, 33.9%; radiographer's fault, 27.4%; film fault, 19.3%; processing fault, 10.8% and patient's fault, 8.6%. The average repeat rate in the first 6 months of study reduced by 50% in the last 6 months. This was due to the effectiveness of implementation of corrective actions. The overall repeat rate was found to correlate well with both the equipment fault and radiographer's fault with correlation coefficients, r, of 0.94 and 0.91, respectively. It is expected that a further reduction in the repeat rate will be obtained after the introduction of quality assurance programmes. (author)

  20. Environmental stress induces trinucleotide repeat mutagenesis in human cells.

    Science.gov (United States)

    Chatterjee, Nimrat; Lin, Yunfu; Santillan, Beatriz A; Yotnda, Patricia; Wilson, John H

    2015-03-24

    The dynamic mutability of microsatellite repeats is implicated in the modification of gene function and disease phenotype. Studies of the enhanced instability of long trinucleotide repeats (TNRs)-the cause of multiple human diseases-have revealed a remarkable complexity of mutagenic mechanisms. Here, we show that cold, heat, hypoxic, and oxidative stresses induce mutagenesis of a long CAG repeat tract in human cells. We show that stress-response factors mediate the stress-induced mutagenesis (SIM) of CAG repeats. We show further that SIM of CAG repeats does not involve mismatch repair, nucleotide excision repair, or transcription, processes that are known to promote TNR mutagenesis in other pathways of instability. Instead, we find that these stresses stimulate DNA rereplication, increasing the proportion of cells with >4 C-value (C) DNA content. Knockdown of the replication origin-licensing factor CDT1 eliminates both stress-induced rereplication and CAG repeat mutagenesis. In addition, direct induction of rereplication in the absence of stress also increases the proportion of cells with >4C DNA content and promotes repeat mutagenesis. Thus, environmental stress triggers a unique pathway for TNR mutagenesis that likely is mediated by DNA rereplication. This pathway may impact normal cells as they encounter stresses in their environment or during development or abnormal cells as they evolve metastatic potential.

  1. Experimental study on acquisition of knowledge through repeated education and training

    International Nuclear Information System (INIS)

    Sasou, Kunihide; Suzuki, Tomohiro; Yoshimura, Seiichi; Kitamura, Masaharu.

    1997-01-01

    Considering the educational methodology to bring up nuclear power plant operators, the experiments are conducted to discuss the relation between the educational backgrounds of subjects and the knowledge acquired through education and training and also to discuss the effects of repeated training on knowledge acquisition. The results show that the knowledge the subjects obtained through the training depends on their educational backgrounds. The subjects with the higher educational backgrounds seem to properly reorganize the knowledge for the operations with using their deep and meta knowledge. Therefore they can create anticipative responses and easily identify causes of events. The results also show that the repeated education and training given to the subjects with weaker backgrounds makes their knowledge reorganized and their ability becomes closer to the subjects' one with higher educational backgrounds. These results indicate that the knowledge acquired in the earlier stage of the education and training depends on the subjects' educational backgrounds. However, the repeated education and training compensates for the difference. It is also suggested that it will be possible to bring up operators more effectively and properly if the existence of people with different educational backgrounds is recognized and the education/training depending on the educational backgrounds are realized. (author)

  2. Thermal stability of chicken brain {alpha}-spectrin repeat 17: a spectroscopic study

    Energy Technology Data Exchange (ETDEWEB)

    Brenner, Annette K. [University of Bergen, Department of Chemistry (Norway); Kieffer, Bruno [Ecole Superieure de Biotechnologie de Strasbourg, IGBMC Biomolecular NMR Group, CNRS UMR 7104 (France); Trave, Gilles [Ecole Superieure de Biotechnologie de Strasbourg, Equipe Oncoproteines, IREBS, UMR 7242 (France); Froystein, Nils Age [University of Bergen, Department of Chemistry (Norway); Raae, Arnt J., E-mail: arnt.raae@mbi.uib.no [University of Bergen, Department of Molecular Biology (Norway)

    2012-06-15

    Spectrin is a rod-like multi-modular protein that is mainly composed of triple-helical repeats. These repeats show very similar 3D-structures but variable conformational and thermodynamical stabilities, which may be of great importance for the flexibility and dynamic behaviour of spectrin in the cell. For instance, repeat 17 (R17) of the chicken brain spectrin {alpha}-chain is four times less stable than neighbouring repeat 16 (R16) in terms of Increment G. The structure of spectrin repeats has mainly been investigated by X-ray crystallography, but the structures of a few repeats, e.g. R16, have also been determined by NMR spectroscopy. Here, we undertook a detailed characterization of the neighbouring R17 by NMR spectroscopy. We assigned most backbone resonances and observed NOE restraints, relaxation values and coupling constants that all indicated that the fold of R17 is highly similar to that of R16, in agreement with previous X-ray analysis of a tandem repeat of the two domains. However, {sup 15}N heteronuclear NMR spectra measured at different temperatures revealed particular features of the R17 domain that might contribute to its lower stability. Conformational exchange appeared to alter the linker connecting R17 to R16 as well as the BC-loop in close proximity. In addition, heat-induced splitting was observed for backbone resonances of a few spatially related residues including V99 of helix C, which in R16 is replaced by the larger hydrophobic tryptophan residue that is relatively conserved among other spectrin repeats. These data support the view that the substitution of tryptophan by valine at this position may contribute to the lower stability of R17.

  3. Reconfigurable multiport EPON repeater

    Science.gov (United States)

    Oishi, Masayuki; Inohara, Ryo; Agata, Akira; Horiuchi, Yukio

    2009-11-01

    An extended reach EPON repeater is one of the solutions to effectively expand FTTH service areas. In this paper, we propose a reconfigurable multi-port EPON repeater for effective accommodation of multiple ODNs with a single OLT line card. The proposed repeater, which has multi-ports in both OLT and ODN sides, consists of TRs, BTRs with the CDR function and a reconfigurable electrical matrix switch, can accommodate multiple ODNs to a single OLT line card by controlling the connection of the matrix switch. Although conventional EPON repeaters require full OLT line cards to accommodate subscribers from the initial installation stage, the proposed repeater can dramatically reduce the number of required line cards especially when the number of subscribers is less than a half of the maximum registerable users per OLT. Numerical calculation results show that the extended reach EPON system with the proposed EPON repeater can save 17.5% of the initial installation cost compared with a conventional repeater, and can be less expensive than conventional systems up to the maximum subscribers especially when the percentage of ODNs in lightly-populated areas is higher.

  4. Repeated dose titration versus age-based method in electroconvulsive therapy: a pilot study.

    Science.gov (United States)

    Aten, Jan Jaap; Oudega, Mardien; van Exel, Eric; Stek, Max L; van Waarde, Jeroen A

    2015-06-01

    In electroconvulsive therapy (ECT), a dose titration method (DTM) was suggested to be more individualized and therefore more accurate than formula-based dosing methods. A repeated DTM (every sixth session and dose adjustment accordingly) was compared to an age-based method (ABM) regarding treatment characteristics, clinical outcome, and cognitive functioning after ECT. Thirty-nine unipolar depressed patients dosed using repeated DTM and 40 matched patients treated with ABM were compared. Montgomery-Åsberg Depression Rating Scale (MADRS) and Mini-Mental State Examination (MMSE) were assessed at baseline and at the end of the index course, as well as the total number of ECT sessions. Both groups were similar regarding age, sex, psychotic features, mean baseline MADRS, and median baseline MMSE. At the end of the index course, the two methods showed equal outcome (mean end MADRS, 11.6 ± 8.3 in DTM and 9.5 ± 7.6 in ABM (P = 0.26); median end MMSE, 28 (25-29) and 28 (25-29.8), respectively (P = 0.81). However, the median number of all ECT sessions differed 16 (11-22) in DTM versus 12 (10-14.8) in ABM; P = 0.02]. Using regression analysis, dosing method and age were independently associated with the total number of ECT sessions, with less sessions needed in ABM (P = 0.02) and in older patients (P = 0.001). In this comparative cohort study, ABM and DTM showed equal outcome for depression and cognition. However, the median ECT course duration in repeated DTM appeared longer. Additionally, higher age was associated with shorter ECT courses regardless of the dosing method. Further prospective studies are needed to confirm these findings.

  5. Dental Fear in Children with Repeated Tooth Injuries.

    Science.gov (United States)

    Negovetić Vranić, Dubravka; Ivančić Jokić, Nataša; Bakarčić, Danko; Carek, Andreja; Rotim, Željko; Verzak, Željko

    2016-06-01

    Tooth injuries are serious clinical conditions. Some children experience dental trauma only once, while others are more prone to repeated tooth injuries. Repeated dental trauma occurs in 19.4% to 30% of patients. Pain and dental trauma are the most common reasons for fear and anxiety. The main objective of this study was to investigate how dental trauma, as well as repeated dental trauma affects the occurrence and development of dental fear in children. The study was conducted on a random sample of 147 subjects (88 boys and 59 girls) aged 5-8 and 9-12 years. Subjects in both age groups were divided into subroups without dental trauma, with one dental trauma and with repeated dental trauma. The validated Children’s Fear Survey Schedule – Dental Subscale was used on fear assessment. Results showed that only 12.2% of children without trauma, 33.3% with one trauma and 51.7% with repeated trauma were not afraid of injection. Older children had a significantly lower fear of injections, touch of an unknown person, choking, going to the hospital and people in white uniforms. Dentist was not the cause of fear in 65.5% of patients with repeated trauma. With each repeated injury of teeth, the degree of their fear of dental treatment was lower.

  6. Assessing the repeatability of terrestrial laser scanning for monitoring gully topography: A case study from Aratula, Queensland, Australia

    Science.gov (United States)

    Goodwin, Nicholas Robert; Armston, John; Stiller, Isaac; Muir, Jasmine

    2016-06-01

    Terrestrial laser scanning (TLS) technology is a powerful tool for quantifying gully morphology and monitoring change over time. This is due to the high sampling density, sub-centimetre positional accuracies (x, y, z), flexibility of survey configurations and ability to link multiple TLS scans together. However, to ensure correct interpretation of results, research is needed to test the repeatability of TLS derived products to quantify the accuracy and separate 'false' from 'true' geomorphic change. In this study, we use the RIEGL VZ400 scanner to test the repeatability of TLS datasets for mapping gully morphology. We then quantify change following a rainfall event of approximately 100 mm. Our study site, located in south-east Queensland, Australia was chosen to be challenging from a repeatability perspective with high topographic variability. The TLS data capture involved three sets of linked scans: one survey pre-rainfall, to be compared to two surveys post-rainfall acquired on consecutive days. Change is considered negligible in the two post-rainfall scans to test survey repeatability. To verify TLS accuracy, an independent dataset of gully extent and spot heights were acquired using traditional total station techniques. Results confirm that the TLS datasets can be registered multi-temporally at sub-centimetre levels of accuracy in three dimensions. Total station and TLS elevation samples showed strong agreement with a mean error and standard deviation (SD) of residuals equal to 0.052 and 0.047 m, respectively (n = 889). Significantly, our repeatability tests found that return type and pulse deviation influence the accuracy and repeatability of DEMs in gully environments. Analysis of consecutive day datasets showed that DEMs derived from first return data recorded 40% higher SD of residual error than DEMs using multiple return data. A significant empirical relationship between pulse deviation and the variance of residuals for repeat DEMs is also shown (r2 = 0

  7. Impact of Inclusion or Exclusion of Repeaters on Test Equating

    Science.gov (United States)

    Puhan, Gautam

    2011-01-01

    This study examined the effect of including or excluding repeaters on the equating process and results. New forms of two tests were equated to their respective old forms using either all examinees or only the first timer examinees in the new form sample. Results showed that for both tests used in this study, including or excluding repeaters in the…

  8. Maintaining confidentiality in prospective studies: anonymous repeated measurements via email (ARME) procedure.

    Science.gov (United States)

    Carli, Vladimir; Hadlaczky, Gergö; Wasserman, Camilla; Stingelin-Giles, Nicola; Reiter-Theil, Stella; Wasserman, Danuta

    2012-02-01

    Respecting and protecting the confidentiality of data and the privacy of individuals regarding the information that they have given as participants in a research project is a cornerstone of complying with accepted research standards. However, in longitudinal studies, establishing and maintaining privacy is often challenging because of the necessity of repeated contact with participants. A novel internet-based solution is introduced here, which maintains privacy while at the same time ensures linkage of data to individual participants in a repeated measures design. With the use of the anonymous repeated measurements via email (ARME) procedure, two separate one-way communication systems are established through ad hoc email accounts and a secure study website. Strengths and limitations of the approach are discussed.

  9. Exposing Students to Repeat Photography: Increasing Cultural Understanding on a Short-Term Study Abroad

    Science.gov (United States)

    Lemmons, Kelly K.; Brannstrom, Christian; Hurd, Danielle

    2014-01-01

    Traditionally, repeat photography has been used to analyze land cover change. This paper describes how repeat photography may be used as a tool to enhance the short-term study abroad experience by facilitating cultural interaction and understanding. We present evidence from two cases and suggest a five-step repeat photography method for educators…

  10. Perfectionism and negative affect after repeated failure: Anxiety, depression, and anger

    OpenAIRE

    Stoeber, Joachim; Schneider, Natalia; Hussain, Rimi; Matthews, Kelly

    2014-01-01

    Perfectionists have shown increased negative affect after failure compared to nonperfectionists. However, little is known about how perfectionists react to repeated failure. This study investigated the effects of two forms of perfectionism--self-oriented perfectionism and socially prescribed perfectionism--on 100 university students’ reactions to repeated failure (versus repeated success) examining three negative emotions: anxiety, depression, and anger. Results showed that socially prescribe...

  11. Computational study of the human dystrophin repeats: interaction properties and molecular dynamics.

    Directory of Open Access Journals (Sweden)

    Baptiste Legrand

    Full Text Available Dystrophin is a large protein involved in the rare genetic disease Duchenne muscular dystrophy (DMD. It functions as a mechanical linker between the cytoskeleton and the sarcolemma, and is able to resist shear stresses during muscle activity. In all, 75% of the dystrophin molecule consists of a large central rod domain made up of 24 repeat units that share high structural homology with spectrin-like repeats. However, in the absence of any high-resolution structure of these repeats, the molecular basis of dystrophin central domain's functions has not yet been deciphered. In this context, we have performed a computational study of the whole dystrophin central rod domain based on the rational homology modeling of successive and overlapping tandem repeats and the analysis of their surface properties. Each tandem repeat has very specific surface properties that make it unique. However, the repeats share enough electrostatic-surface similarities to be grouped into four separate clusters. Molecular dynamics simulations of four representative tandem repeats reveal specific flexibility or bending properties depending on the repeat sequence. We thus suggest that the dystrophin central rod domain is constituted of seven biologically relevant sub-domains. Our results provide evidence for the role of the dystrophin central rod domain as a scaffold platform with a wide range of surface features and biophysical properties allowing it to interact with its various known partners such as proteins and membrane lipids. This new integrative view is strongly supported by the previous experimental works that investigated the isolated domains and the observed heterogeneity of the severity of dystrophin related pathologies, especially Becker muscular dystrophy.

  12. A study on the repeatability of ultrasonic testing data

    International Nuclear Information System (INIS)

    Yoshimura, Seiichi; Fukumoto, Hiroshi

    1980-01-01

    Reliability improvement of ultrasonic testing data is strongly desired in ultrasonic testing working of nuclear power plants. This paper deals with the problems of the testing by the manual and the remote control apparatus, and with the factors which influence the repeatability of ultrasonic testing data. Following results are found in it. (1) In the testing by the manual, working time and posture influence the repeatability of testing data. (2) Glycerin in suitable for the couplant in the respect of the repeatability of testing data. In the case of using machine oil, the pressure to the probe necessitates to be over 0.2 kg/cm 2 . (3) In the testing by the remote control apparatus, working time, working environment and defect position does not influence the repeatability of testing data. (author)

  13. PET functional volume delineation: a robustness and repeatability study

    International Nuclear Information System (INIS)

    Hatt, Mathieu; Cheze-le Rest, Catherine; Albarghach, Nidal; Pradier, Olivier; Visvikis, Dimitris

    2011-01-01

    Current state-of-the-art algorithms for functional uptake volume segmentation in PET imaging consist of threshold-based approaches, whose parameters often require specific optimization for a given scanner and associated reconstruction algorithms. Different advanced image segmentation approaches previously proposed and extensively validated, such as among others fuzzy C-means (FCM) clustering, or fuzzy locally adaptive bayesian (FLAB) algorithm have the potential to improve the robustness of functional uptake volume measurements. The objective of this study was to investigate robustness and repeatability with respect to various scanner models, reconstruction algorithms and acquisition conditions. Robustness was evaluated using a series of IEC phantom acquisitions carried out on different PET/CT scanners (Philips Gemini and Gemini Time-of-Flight, Siemens Biograph and GE Discovery LS) with their associated reconstruction algorithms (RAMLA, TF MLEM, OSEM). A range of acquisition parameters (contrast, duration) and reconstruction parameters (voxel size) were considered for each scanner model, and the repeatability of each method was evaluated on simulated and clinical tumours and compared to manual delineation. For all the scanner models, acquisition parameters and reconstruction algorithms considered, the FLAB algorithm demonstrated higher robustness in delineation of the spheres with low mean errors (10%) and variability (5%), with respect to threshold-based methodologies and FCM. The repeatability provided by all segmentation algorithms considered was very high with a negligible variability of <5% in comparison to that associated with manual delineation (5-35%). The use of advanced image segmentation algorithms may not only allow high accuracy as previously demonstrated, but also provide a robust and repeatable tool to aid physicians as an initial guess in determining functional volumes in PET. (orig.)

  14. REPEATABILITY OF FRUIT QUALITY TRAITS OF CACTUS PEAR

    Directory of Open Access Journals (Sweden)

    VALTÂNIA XAVIER NUNES

    2017-12-01

    Full Text Available ABSTRACT Repeatability analysis has been used to study traits in several crops, assisting in the definition of the minimum number needed to evaluate genotypes more efficiently and with less time and resource consumption. So far, however, no repeatability studies on cactus pear have been found in the literature. The objective of this study was to determine the coefficient of repeatability for cactus pear fruits traits and the minimum number of evaluations (fruit that can provide acceptable accuracy for the prediction of the true value. The experiment was conducted at the Federal Institute of Bahia/Campus Guanambi, with 150 fruits collected from three municipalities in the state of Bahia. The coefficients of repeatability were estimated by the methods of analysis of variance, principal components based on the covariance (PCCV and correlation (PCC matrices, and structural analysis based on the correlation matrix (SA. The analysis of variance showed that, except for fruit diameter, the effect of the production site (municipality was significant for all traits evaluated. The PCCV method was proven the most suitable for studying the repeatability of quality traits of cactus pear fruits. Seven fruits were required to determine, with 90% confidence, the traits length, diameter, fruit firmness, skin thickness, number of seeds, fruit mass, bark mass, pulp mass, pH, titratable acidity, soluble solids, SS/AT ratio, and pulp yield.

  15. Automated genotyping of dinucleotide repeat markers

    Energy Technology Data Exchange (ETDEWEB)

    Perlin, M.W.; Hoffman, E.P. [Carnegie Mellon Univ., Pittsburgh, PA (United States)]|[Univ. of Pittsburgh, PA (United States)

    1994-09-01

    The dinucleotide repeats (i.e., microsatellites) such as CA-repeats are a highly polymorphic, highly abundant class of PCR-amplifiable markers that have greatly streamlined genetic mapping experimentation. It is expected that over 30,000 such markers (including tri- and tetranucleotide repeats) will be characterized for routine use in the next few years. Since only size determination, and not sequencing, is required to determine alleles, in principle, dinucleotide repeat genotyping is easily performed on electrophoretic gels, and can be automated using DNA sequencers. Unfortunately, PCR stuttering with these markers generates not one band for each allele, but a pattern of bands. Since closely spaced alleles must be disambiguated by human scoring, this poses a key obstacle to full automation. We have developed methods that overcome this obstacle. Our model is that the observed data is generated by arithmetic superposition (i.e., convolution) of multiple allele patterns. By quantitatively measuring the size of each component band, and exploiting the unique stutter pattern associated with each marker, closely spaced alleles can be deconvolved; this unambiguously reconstructs the {open_quotes}true{close_quotes} allele bands, with stutter artifact removed. We used this approach in a system for automated diagnosis of (X-linked) Duchenne muscular dystrophy; four multiplexed CA-repeats within the dystrophin gene were assayed on a DNA sequencer. Our method accurately detected small variations in gel migration that shifted the allele size estimate. In 167 nonmutated alleles, 89% (149/167) showed no size variation, 9% (15/167) showed 1 bp variation, and 2% (3/167) showed 2 bp variation. We are currently developing a library of dinucleotide repeat patterns; together with our deconvolution methods, this library will enable fully automated genotyping of dinucleotide repeats from sizing data.

  16. Studies on Section XI ultrasonic repeatability

    International Nuclear Information System (INIS)

    Jamison, T.D.; McDearman, W.R.

    1981-05-01

    A block representative of a nuclear component has been welded containing intentional defects. Acoustic emission data taken during the welding correlate well with ultrasonic data. Repetitive ultrasonic examinations have been performed by skilled operators using a procedure based on that desribed in ASME Section XI. These examinations were performed by different examination teams using different ultrasonic equipment in such a manner that the effects on the repeatability of the ultrasonic test method caused by the operator and by the use of different equipment could be estimated. It was tentatively concluded that when considering a large number of inspections: (1) there is no significant difference in indication sizing between operators, and (2) there is a significant difference in amplitude and defect sizing when instruments having different, Code acceptable operating characteristics are used. It was determined that the Section XI sizing parameters follow a bivariate normal distribution. Data derived from ultrasonically and physically sizing indications in nuclear components during farication show that the Section XI technique tends to overestimate the size of the reflectors

  17. Study of four week repeated dose toxic test of Sweet Bee Venom in Beagle Dogs

    Directory of Open Access Journals (Sweden)

    Jae-Seuk Park

    2010-12-01

    Full Text Available Objectives: This study was performed to analyse four week repeated dose toxicity of Sweet Bee Venom(Sweet BV extracted from the bee venom in Beagle dogs. Methods: All experiments were conducted under the regulations of Good Laboratory Practice (GLP at Biotoxtech Company, a non-clinical study authorized institution. Male and female Beagle dogs of 5-6 months old were chosen for the pilot study of four week repeated dose toxicity of Sweet BV which was administered at the level of 0.56㎎/㎏ body weight which is eighty times higher than the clinical application dosage as the high dosage, followed by 0.28 and 0.14㎎/㎏ as midium and low dosage, respectively. Equal amount of excipient(normal saline to the Sweet BV experiment groups was administered as the control group every day for four weeks. Results: 1. No mortality was witnessed in all of the experiment groups. 2. All experiment groups were appealed pain sense in the treating time compared to the control group, and hyperemia and movement disorder were observed around the area of administration in all experiment groups, and higher occurrence in the higher dosage treatment. 3. For weight measurement, Neither male nor female groups showed significant changes. 4. In the urine analysis, CBC and biochemistry didn't show any significant changes in the experiment groups compared with control group. 5. For weight measurement of organs, experiment groups didn't show any significant changes compared with control group. 6. To verify abnormalities of organs and tissues, thigh muscle which treated with Sweet BV, cerebrum, liver, lung, kidney, and spinal cords were removed and conducted histologocal observation with H-E staining. In the histologocal observation of thigh muscle, cell infiltration, inflammatory, degeneration, necrosis of muscle fiber, and fibrosis were found in both thigh tissue. And the changes were depend on the dose of Sweet BV. But another organs were not detected in any abnormalities. 7

  18. Repeating Marx

    DEFF Research Database (Denmark)

    Fuchs, Christian; Monticelli, Lara

    2018-01-01

    This introduction sets out the context of the special issue “Karl Marx @ 200: Debating Capitalism & Perspectives for the Future of Radical Theory”, which was published on the occasion of Marx’s bicentenary on 5 May 2018. First, we give a brief overview of contemporary capitalism’s development...... and its crises. Second, we argue that it is important to repeat Marx today. Third, we reflect on lessons learned from 200 years of struggles for alternatives to capitalism. Fourth, we give an overview of the contributions in this special issue. Taken together, the contributions in this special issue show...... that Marx’s theory and politics remain key inspirations for understanding exploitation and domination in 21st-century society and for struggles that aim to overcome these phenomena and establishing a just and fair society. We need to repeat Marx today....

  19. SGR-like behaviour of the repeating FRB 121102

    Energy Technology Data Exchange (ETDEWEB)

    Wang, F.Y.; Yu, H., E-mail: fayinwang@nju.edu.cn, E-mail: yuhai@smail.nju.edu.cn [School of Astronomy and Space Science, Nanjing University, 163 Xianlin Avenue, Nanjing, 210093 China (China)

    2017-03-01

    Fast radio bursts (FRBs) are millisecond-duration radio signals occurring at cosmological distances. However the physical model of FRBs is mystery, many models have been proposed. Here we study the frequency distributions of peak flux, fluence, duration and waiting time for the repeating FRB 121102. The cumulative distributions of peak flux, fluence and duration show power-law forms. The waiting time distribution also shows power-law distribution, and is consistent with a non-stationary Poisson process. These distributions are similar as those of soft gamma repeaters (SGRs). We also use the statistical results to test the proposed models for FRBs. These distributions are consistent with the predictions from avalanche models of slowly driven nonlinear dissipative systems.

  20. Role of memory errors in quantum repeaters

    International Nuclear Information System (INIS)

    Hartmann, L.; Kraus, B.; Briegel, H.-J.; Duer, W.

    2007-01-01

    We investigate the influence of memory errors in the quantum repeater scheme for long-range quantum communication. We show that the communication distance is limited in standard operation mode due to memory errors resulting from unavoidable waiting times for classical signals. We show how to overcome these limitations by (i) improving local memory and (ii) introducing two operational modes of the quantum repeater. In both operational modes, the repeater is run blindly, i.e., without waiting for classical signals to arrive. In the first scheme, entanglement purification protocols based on one-way classical communication are used allowing to communicate over arbitrary distances. However, the error thresholds for noise in local control operations are very stringent. The second scheme makes use of entanglement purification protocols with two-way classical communication and inherits the favorable error thresholds of the repeater run in standard mode. One can increase the possible communication distance by an order of magnitude with reasonable overhead in physical resources. We outline the architecture of a quantum repeater that can possibly ensure intercontinental quantum communication

  1. One way quantum repeaters with quantum Reed-Solomon codes

    OpenAIRE

    Muralidharan, Sreraman; Zou, Chang-Ling; Li, Linshu; Jiang, Liang

    2018-01-01

    We show that quantum Reed-Solomon codes constructed from classical Reed-Solomon codes can approach the capacity on the quantum erasure channel of $d$-level systems for large dimension $d$. We study the performance of one-way quantum repeaters with these codes and obtain a significant improvement in key generation rate compared to previously investigated encoding schemes with quantum parity codes and quantum polynomial codes. We also compare the three generation of quantum repeaters using quan...

  2. Quantum key distribution with two-segment quantum repeaters

    Energy Technology Data Exchange (ETDEWEB)

    Kampermann, Hermann; Abruzzo, Silvestre; Bruss, Dagmar [Theoretische Physik III, Heinrich-Heine-Universitaet Duesseldorf (Germany)

    2014-07-01

    Quantum repeaters represent one possible way to achieve long-distance quantum key distribution. One way of improving the repeater rate and decreasing the memory coherence time is the usage of multiplexing. Motivated by the experimental fact that long-range connections are practically demanding, we extend the analysis of the quantum repeater multiplexing protocol to the case of short-range connections. We derive formulas for the repeater rate and we show that short-range connections lead to most of the benefits of a full-range multiplexing protocol. A less demanding QKD-protocol without quantum memories was recently introduced by Lo et al. We generalize this measurement-device-independent quantum key Distribution protocol to the scenario where the repeater Station contains also heralded quantum memories. We assume either single-photon sources or weak coherent pulse sources plus decay states. We show that it is possible to significantly outperform the original proposal, even in presence of decoherence of the quantum memory. We give formulas in terms of device imperfections i.e., the quantum bit error rate and the repeater rate.

  3. A tetranucleotide repeat (D4S1652) is linked to facioscapulohumeral dystrophy and shows no linkage disequilibrium with the disease

    Energy Technology Data Exchange (ETDEWEB)

    Mathews, K.D.; Bailey, H.L.; Mills, K.A. [and others

    1994-09-01

    Facioscapulohumeral dystrophy (FSHD) is an autosomal dominant dystrophy which is associated with a deletion in a subtelomeric repeat element on 4q35. The gene has not yet been identified. The probe detecting this deletion (D4F104S1) is not chromosome 4-specific, and at least one large family has been identified which is not linked to chromosome 4. Thus, persymptomatic/prenatal diagnosis can only be provided to families that are proven to be chromosome 4-linked or where a new mutation is demonstrated. The markers available to demonstrate linkage to chromosome 4, D4S139, D4S163, and D4F35S1, are VNTRs. We have used D4S1652, a tetranucleotide repeat recently identified by the Cooperative Human Linkage Center, in our FSHD families. We found it is completely linked to the 4q35 VNTRs and to the disease phenotype. Physical mapping, using radiation hybrids and somatic cell hybrids, places D4S1652 between D4S139, an interval of approximately 1 Mb. We have used D4S1652 to look for linkage disequilibrium in our FSHD patient population. This result is of interest because of our hypothesis that the deletion in the subtelomeric repeat element alters transcription of a more proximal gene through a position effect. Previously available markers have been unsatisfactory for this experiment because of difficulty comparing numerous VNTR alleles across families. We observed 4, easily distinguished, D4S1652 alleles in our families. We studied 14 chromosomes associated with disease phenotype and 55 chromosomes from nontransmitting parents. We found no evidence for linkage disequilibrium ({chi}{sup 2}=1.313, nonsignificant). This result will need confirmation with a larger patient population, but is consistent with the clinical observation that there is a high rate of a new mutation in this disorder.

  4. Study of four weeks repeated-dose toxic test of Sweet Bee Venom in rats Original Articles

    Directory of Open Access Journals (Sweden)

    Kwon Hae-Yon

    2011-03-01

    Full Text Available Objectives: This study was performed to analyse four weeks repeated -dose toxicity of Sweet Bee Venom (SBV-pure melittin, the major component of honey bee venom in rats. Methods: All experiments were conducted under the regulations of Good Laboratory Practice (GLPat Biotoxtech Company, a non-clinical study authorized institution. Male and female rats of 5 weeks old were chosen for the pilot study of four weeks repeated-dose toxicity and was injected at the level of 0.56 mg/kg body weight (eighty times higher than the clinical application dosage as the high dosage, followed by 0.28 and 0.14 mg/kg as midium and low dosage, respectively. Equal amount of normal saline was injected as the control group every day for four weeks. Results: 1. No mortality was witnessed in all of the experiment groups. 2. All experiment groups appealed pain sense in the treating time compared to the control group, and side effects such as hyperemia and movement disorder were observed around the area of injection in all experiment groups, and the higher dosage in treatment, the higher occurrence in side effects. 3. Concerning weight measurement, neither male nor female groups showed significant changes compared to the control group. 4. Concerning to the CBC and biochemistry, all experiment groups didn't show any significant changes compared to the control group. 5. Concerning weight measurement of organs, experiment groups didn't show any significant changes compared to the control group. 6. To verify abnormalities of organs and tissues, those such as cerebellum, cerebrum, liver, lung, kidney,and spinal cords were removed and we conducted histologocal observation with H-E staining.Concerning the histologocal observation of liver tissues, some fatty changes were observed around portal vein in 0.56 mg/kg experiment group. But another organs were not detected in any abnormalities. 7. The proper high dosage of SBV for the thirteen weeks repeated test in rats may be 0.28 mg

  5. Education for patients with chronic kidney disease in Taiwan: a prospective repeated measures study.

    Science.gov (United States)

    Yen, Miaofen; Huang, Jeng-Jong; Teng, Hsiu-Lan

    2008-11-01

    To investigate the physical, knowledge and quality of life outcomes of an educational intervention for patients with early stage chronic kidney disease. A comprehensive predialysis education care team can be effective in slowing the progression of chronic kidney disease. A single group repeated measures design was used to evaluate the effects of the intervention. Participants were recruited through health department community health screen data banks. A predialysis, team-delivered educational intervention covering renal function health care, dietary management of renal function and the effects of Chinese herb medication on renal function was designed and implemented. Data were collected at baseline, six and 12 months. Study outcomes included physical indicators, knowledge (renal function protection, use of Chinese herbs and renal function and diet) and quality of life. Data were analysed using repeated measure anova to test for change over time in outcome variables. Sixty-six persons participated in this study. The predialysis educational intervention showed significant differences at the three time points in overall knowledge scores, waist-hip ratio, body mass index and global health status. Knowledge measures increased at month 6 and decreased at month 12. The primary indicator of renal function, glomerular filtration rate, remained stable throughout the 12 months of follow-up, despite the relatively older mean age of study participants. A predialysis education care team can provide effective disease-specific knowledge and may help retard deterioration of renal function in persons with early-stage chronic kidney disease. The intervention dose may need to be repeated every six months to maintain knowledge effects. A predialysis educational program with disease-specific knowledge and information is feasible and may provide positive outcomes for patients. Topics on the uses of Chinese herbs should be included for people who are likely to use alternative therapies.

  6. Isolation of human simple repeat loci by hybridization selection.

    Science.gov (United States)

    Armour, J A; Neumann, R; Gobert, S; Jeffreys, A J

    1994-04-01

    We have isolated short tandem repeat arrays from the human genome, using a rapid method involving filter hybridization to enrich for tri- or tetranucleotide tandem repeats. About 30% of clones from the enriched library cross-hybridize with probes containing trimeric or tetrameric tandem arrays, facilitating the rapid isolation of large numbers of clones. In an initial analysis of 54 clones, 46 different tandem arrays were identified. Analysis of these tandem repeat loci by PCR showed that 24 were polymorphic in length; substantially higher levels of polymorphism were displayed by the tetrameric repeat loci isolated than by the trimeric repeats. Primary mapping of these loci by linkage analysis showed that they derive from 17 chromosomes, including the X chromosome. We anticipate the use of this strategy for the efficient isolation of tandem repeats from other sources of genomic DNA, including DNA from flow-sorted chromosomes, and from other species.

  7. Reduction in gesture during the production of repeated references

    NARCIS (Netherlands)

    Hoetjes, M.W.; Koolen, R.M.F.; Goudbeek, M.B.; Krahmer, E.J.; Swerts, M.G.J.

    2015-01-01

    In dialogue, repeated references contain fewer words (which are also acoustically reduced) and fewer gestures than initial ones. In this paper, we describe three experiments studying to what extent gesture reduction is comparable to other forms of linguistic reduction. Since previous studies showed

  8. Film repeats in radiology department

    International Nuclear Information System (INIS)

    Suwan, A. Z.; Al-Shakharah, A. I

    1997-01-01

    During a one year period, 4910 radiographs of 55780 films were repeated. The objective of our study was to analyse and to classify the causes in order to minimize the repeats, cut the expenses and to provide optimal radiographs for accurate diagnosis. Analysis of the different factors revealed that, 43.6% of film repeats in our service were due to faults in exposure factors, centering comprises 15.9% of the repeats, while too much collimation was responsible for 7.6% of these repeats. All of which can be decreased by awareness and programmed training of technicians. Film blurring caused by patient motion was also responsible for 4.9% for radiographs reexamination, which can be minimized by detailed explanation to the patient and providing the necessary privacy. Fogging of X-Ray films by improper storage or inadequate handling or processing faults were responsible for 14.5% in repeats in our study. Methods and criteria for proper storage and handling of films were discussed. Recommendation for using modern day-light and laser processor has been high lighted. Artefacts are noticeably high in our cases, due to spinal dresses and frequent usage of precious metals for c osmotic purposes in this part of the world. The repeated films comprise 8.8% of all films We conclude that, the main factor responsible for repeats of up to 81.6% of cases was the technologists, thus emphasizing the importance of adequate training of the technologists. (authors). 15 refs., 9 figs., 1 table

  9. Does Dry Eye Affect Repeatability of Corneal Topography Measurements?

    Directory of Open Access Journals (Sweden)

    Aysun Şanal Doğan

    2018-04-01

    Full Text Available Objectives: The purpose of this study was to assess the repeatability of corneal topography measurements in dry eye patients and healthy controls. Materials and Methods: Participants underwent consecutive corneal topography measurements (Sirius; Costruzione Strumenti Oftalmici, Florence, Italy. Two images with acquisition quality higher than 90% were accepted. The following parameters were evaluated: minimum and central corneal thickness, aqueous depth, apex curvature, anterior chamber volume, horizontal anterior chamber diameter, iridocorneal angle, cornea volume, and average simulated keratometry. Repeatability was assessed by calculating intra-class correlation coefficient. Results: Thirty-three patients with dry eye syndrome and 40 healthy controls were enrolled to the study. The groups were similar in terms of age (39 [18-65] vs. 30.5 [18-65] years, p=0.198 and gender (M/F: 4/29 vs. 8/32, p=0.366. Intra-class correlation coefficients among all topography parameters within both groups showed excellent repeatability (>0.90. Conclusion: The anterior segment measurements provided by the Sirius corneal topography system were highly repeatable for dry eye patients and are sufficiently reliable for clinical practice and research.

  10. Does Dry Eye Affect Repeatability of Corneal Topography Measurements?

    Science.gov (United States)

    Doğan, Aysun Şanal; Gürdal, Canan; Köylü, Mehmet Talay

    2018-04-01

    The purpose of this study was to assess the repeatability of corneal topography measurements in dry eye patients and healthy controls. Participants underwent consecutive corneal topography measurements (Sirius; Costruzione Strumenti Oftalmici, Florence, Italy). Two images with acquisition quality higher than 90% were accepted. The following parameters were evaluated: minimum and central corneal thickness, aqueous depth, apex curvature, anterior chamber volume, horizontal anterior chamber diameter, iridocorneal angle, cornea volume, and average simulated keratometry. Repeatability was assessed by calculating intra-class correlation coefficient. Thirty-three patients with dry eye syndrome and 40 healthy controls were enrolled to the study. The groups were similar in terms of age (39 [18-65] vs. 30.5 [18-65] years, p=0.198) and gender (M/F: 4/29 vs. 8/32, p=0.366). Intra-class correlation coefficients among all topography parameters within both groups showed excellent repeatability (>0.90). The anterior segment measurements provided by the Sirius corneal topography system were highly repeatable for dry eye patients and are sufficiently reliable for clinical practice and research.

  11. Structure of thrombospondin type 3 repeats in bacterial outer membrane protein A reveals its intra-repeat disulfide bond-dependent calcium-binding capability

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Shuyan; Sun, Cancan; Tan, Kemin; Ye, Sheng; Zhang, Rongguang

    2017-09-01

    Eukaryotic thrombospondin type 3 repeat (TT3R) is an efficient calcium ion (Ca2+) binding motif only found in mammalian thrombospondin family. TT3R has also been found in prokaryotic cellulase Cel5G, which was thought to forfeit the Ca2+-binding capability due to the formation of intra-repeat disulfide bonds, instead of the inter-repeat ones possessed by eukaryotic TT3Rs. In this study, we have identified an enormous number of prokaryotic TT3R-containing proteins belonging to several different protein families, including outer membrane protein A (OmpA), an important structural protein connecting the outer membrane and the periplasmic peptidoglycan layer in gram-negative bacteria. Here, we report the crystal structure of the periplasmic region of OmpA from Capnocytophaga gingivalis, which contains a linker region comprising five consecutive TT3Rs. The structure of OmpA-TT3R exhibits a well-ordered architecture organized around two tightly-coordinated Ca2+ and confirms the presence of abnormal intra-repeat disulfide bonds. Further mutagenesis studies showed that the Ca2+-binding capability of OmpA-TT3R is indeed dependent on the proper formation of intra-repeat disulfide bonds, which help to fix a conserved glycine residue at its proper position for Ca2+ coordination. Additionally, despite lacking inter repeat disulfide bonds, the interfaces between adjacent OmpA-TT3Rs are enhanced by both hydrophobic and conserved aromatic-proline interactions.

  12. Repeat Chlamydia trachomatis testing among heterosexual STI outpatient clinic visitors in the Netherlands: a longitudinal study.

    Science.gov (United States)

    Visser, Maartje; van Aar, Fleur; Koedijk, Femke D H; Kampman, Carolina J G; Heijne, Janneke C M

    2017-12-20

    Chlamydia infections are common in both men and women, are often asymptomatic and can cause serious complications. Repeat testing in high-risk groups is therefore indicated. In the Netherlands, guidelines on repeat chlamydia testing differ between testing facilities, and knowledge on repeat testing behaviour is limited. Here, we analyse the current repeat testing behaviour of heterosexual STI clinic visitors, and aim to identify groups for which repeat testing advice could be advantageous. Longitudinal surveillance data from all Dutch STI outpatient clinics were used, which included all STI clinic consultations carried out among heterosexual men and women between June 2014 and December 2015. Repeat testing was defined as returning to the same STI clinic between 35 days and 12 months after initial consultation. We calculated chlamydia positivity at repeat test stratified by initial test result and time between consultations. Logistic regression analyses were used to identify predictors of repeat testing, and predictors of having a chlamydia positive repeat test. In total, 140,486 consultations in 75,487 women and 46,286 men were available for analyses. Overall, 15.4% of women and 11.1% of men returned to the STI clinic within the study period. Highest chlamydia positivity at repeat test was seen 3-5 months after initial positive test. Among both women and men, repeat testing was associated with non-Western ethnicity, having had more than two sex partners in the past 6 months, reporting STI symptoms, having a history of STI, and having a chlamydia positive initial test. Among repeat testers, chlamydia positive repeat test was most strongly associated with younger age, followed by a chlamydia positive initial test. Repeat testing most often resulted in a positive test result among young heterosexuals (<25) and heterosexuals of any age with a chlamydia infection at the initial consultation. Further efforts are needed to determine optimal repeat testing strategies.

  13. DNA-binding proteins from marine bacteria expand the known sequence diversity of TALE-like repeats.

    Science.gov (United States)

    de Lange, Orlando; Wolf, Christina; Thiel, Philipp; Krüger, Jens; Kleusch, Christian; Kohlbacher, Oliver; Lahaye, Thomas

    2015-11-16

    Transcription Activator-Like Effectors (TALEs) of Xanthomonas bacteria are programmable DNA binding proteins with unprecedented target specificity. Comparative studies into TALE repeat structure and function are hindered by the limited sequence variation among TALE repeats. More sequence-diverse TALE-like proteins are known from Ralstonia solanacearum (RipTALs) and Burkholderia rhizoxinica (Bats), but RipTAL and Bat repeats are conserved with those of TALEs around the DNA-binding residue. We study two novel marine-organism TALE-like proteins (MOrTL1 and MOrTL2), the first to date of non-terrestrial origin. We have assessed their DNA-binding properties and modelled repeat structures. We found that repeats from these proteins mediate sequence specific DNA binding conforming to the TALE code, despite low sequence similarity to TALE repeats, and with novel residues around the BSR. However, MOrTL1 repeats show greater sequence discriminating power than MOrTL2 repeats. Sequence alignments show that there are only three residues conserved between repeats of all TALE-like proteins including the two new additions. This conserved motif could prove useful as an identifier for future TALE-likes. Additionally, comparing MOrTL repeats with those of other TALE-likes suggests a common evolutionary origin for the TALEs, RipTALs and Bats. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  14. Investigation of a Quadruplex-Forming Repeat Sequence Highly Enriched in Xanthomonas and Nostoc sp.

    Directory of Open Access Journals (Sweden)

    Charlotte Rehm

    Full Text Available In prokaryotes simple sequence repeats (SSRs with unit sizes of 1-5 nucleotides (nt are causative for phase and antigenic variation. Although an increased abundance of heptameric repeats was noticed in bacteria, reports about SSRs of 6-9 nt are rare. In particular G-rich repeat sequences with the propensity to fold into G-quadruplex (G4 structures have received little attention. In silico analysis of prokaryotic genomes show putative G4 forming sequences to be abundant. This report focuses on a surprisingly enriched G-rich repeat of the type GGGNATC in Xanthomonas and cyanobacteria such as Nostoc. We studied in detail the genomes of Xanthomonas campestris pv. campestris ATCC 33913 (Xcc, Xanthomonas axonopodis pv. citri str. 306 (Xac, and Nostoc sp. strain PCC7120 (Ana. In all three organisms repeats are spread all over the genome with an over-representation in non-coding regions. Extensive variation of the number of repetitive units was observed with repeat numbers ranging from two up to 26 units. However a clear preference for four units was detected. The strong bias for four units coincides with the requirement of four consecutive G-tracts for G4 formation. Evidence for G4 formation of the consensus repeat sequences was found in biophysical studies utilizing CD spectroscopy. The G-rich repeats are preferably located between aligned open reading frames (ORFs and are under-represented in coding regions or between divergent ORFs. The G-rich repeats are preferentially located within a distance of 50 bp upstream of an ORF on the anti-sense strand or within 50 bp from the stop codon on the sense strand. Analysis of whole transcriptome sequence data showed that the majority of repeat sequences are transcribed. The genetic loci in the vicinity of repeat regions show increased genomic stability. In conclusion, we introduce and characterize a special class of highly abundant and wide-spread quadruplex-forming repeat sequences in bacteria.

  15. Investigation of a Quadruplex-Forming Repeat Sequence Highly Enriched in Xanthomonas and Nostoc sp.

    Science.gov (United States)

    Rehm, Charlotte; Wurmthaler, Lena A; Li, Yuanhao; Frickey, Tancred; Hartig, Jörg S

    2015-01-01

    In prokaryotes simple sequence repeats (SSRs) with unit sizes of 1-5 nucleotides (nt) are causative for phase and antigenic variation. Although an increased abundance of heptameric repeats was noticed in bacteria, reports about SSRs of 6-9 nt are rare. In particular G-rich repeat sequences with the propensity to fold into G-quadruplex (G4) structures have received little attention. In silico analysis of prokaryotic genomes show putative G4 forming sequences to be abundant. This report focuses on a surprisingly enriched G-rich repeat of the type GGGNATC in Xanthomonas and cyanobacteria such as Nostoc. We studied in detail the genomes of Xanthomonas campestris pv. campestris ATCC 33913 (Xcc), Xanthomonas axonopodis pv. citri str. 306 (Xac), and Nostoc sp. strain PCC7120 (Ana). In all three organisms repeats are spread all over the genome with an over-representation in non-coding regions. Extensive variation of the number of repetitive units was observed with repeat numbers ranging from two up to 26 units. However a clear preference for four units was detected. The strong bias for four units coincides with the requirement of four consecutive G-tracts for G4 formation. Evidence for G4 formation of the consensus repeat sequences was found in biophysical studies utilizing CD spectroscopy. The G-rich repeats are preferably located between aligned open reading frames (ORFs) and are under-represented in coding regions or between divergent ORFs. The G-rich repeats are preferentially located within a distance of 50 bp upstream of an ORF on the anti-sense strand or within 50 bp from the stop codon on the sense strand. Analysis of whole transcriptome sequence data showed that the majority of repeat sequences are transcribed. The genetic loci in the vicinity of repeat regions show increased genomic stability. In conclusion, we introduce and characterize a special class of highly abundant and wide-spread quadruplex-forming repeat sequences in bacteria.

  16. Repeatability of the Oxford Foot Model in children with foot deformity.

    Science.gov (United States)

    McCahill, Jennifer; Stebbins, Julie; Koning, Bart; Harlaar, Jaap; Theologis, Tim

    2018-03-01

    The Oxford Foot Model (OFM) is a multi-segment, kinematic model developed to assess foot motion. It has previously been assessed for repeatability in healthy populations. To determine the OFM's reliability for detecting foot deformity, it is important to know repeatability in pathological conditions. The aim of the study was to assess the repeatability of the OFM in children with foot deformity. Intra-tester repeatability was assessed for 45 children (15 typically developing, 15 hemiplegic, 15 clubfoot). Inter-tester repeatability was assessed in the clubfoot population. The mean absolute differences between testers (clubfoot) and sessions (clubfoot and hemiplegic) were calculated for each of 15 clinically relevant, kinematic variables and compared to typically developing children. Children with clubfoot showed a mean difference between visits of 2.9° and a mean difference between raters of 3.6° Mean absolute differences were within one degree for the intra and inter-rater reliability in 12/15 variables. Hindfoot rotation, forefoot/tibia abduction and forefoot supination were the most variable between testers. Overall the clubfoot data were less variable than the typically developing population. Children with hemiplegia demonstrated slightly higher differences between sessions (mean 4.1°), with the most reliable data in the sagittal plane, and largest differences in the transverse plane. The OFM was designed to measure different types of foot deformity. The results of this study show that it provides repeatable results in children with foot deformity. To be distinguished from measurement artifact, changes in foot kinematics as a result of intervention or natural progression over time must be greater than the repeatability reported here. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. A flow-cytometric NK-cytotoxicity assay adapted for use in rat repeated dose toxicity studies

    International Nuclear Information System (INIS)

    Marcusson-Staahl, Maritha; Cederbrant, Karin

    2003-01-01

    A recent regulatory document for immunotoxicity testing of new pharmaceutical drugs includes cytotoxic natural killer (NK)-cell function as a required parameter in repeated dose toxicity studies. The classical 51 Cr-release assay is the conventional test for cytotoxicity testing but several drawbacks with this assay has increased the demand for new reliable test systems. Here, we describe the optimisation of a flow-cytometric cytotoxicity assay especially adapted for regulatory rat studies in drug development. The test principle is based on target cell labelling with 5-(6)-carboxy-fluorescein succinimidyl ester (CFSE) and subsequent DNA-labelling with propidium iodide (PI) for identification of target cells with compromised cell membranes. The results are expressed as percentage of dead targets on a cell-to-cell basis. The final format of the assay includes 0.5 ml peripheral blood, 1.25x10 5 effector cells per sample, and collection of 500 target events by flow-cytometry. When NKR-P1+ cells were removed from the effector cell population by magnetic depletion the relative proportion decreased from 6 to 0.08%. The corresponding cytotoxic activity decreased from 68 to 8%. Also, the cytotoxic activity showed a significant and positive correlation with the proportion of NK-cells present in the effector cell suspension. Thus, the cytotoxicity measured is almost exclusively exerted by NK-cells. The current flow-cytometric test benefits from using peripheral blood as a source for effector cells since it will not conflict with the use of spleen for histopathological investigations in repeated dose toxicity studies. Additionally, since only a minimal number of effector cells are required per sample repeated testing of the same animal is enabled

  18. Mononucleotide repeats are asymmetrically distributed in fungal genes

    NARCIS (Netherlands)

    Passel, van M.W.J.; Graaff, de L.H.

    2008-01-01

    ABSTRACT: BACKGROUND: Systematic analyses of sequence features have resulted in a better characterisation of the organisation of the genome. A previous study in prokaryotes on the distribution of sequence repeats, which are notoriously variable and can disrupt the reading frame in genes, showed that

  19. Construction of a quantum repeater with linear optics

    International Nuclear Information System (INIS)

    Kok, Pieter; Williams, Colin P.; Dowling, Jonathan P.

    2003-01-01

    We study the mechanism and complexity of an efficient quantum repeater, employing double-photon guns, for long-distance optical quantum communication. The guns create polarization-entangled photon pairs on demand. One such source might be a semiconducter quantum dot, which has the distinct advantage over parametric down-conversion that the probability of creating a photon pair is close to 1, while the probability of creating multiple pairs vanishes. The swapping and purifying components are implemented by polarizing beam splitters and probabilistic optical controlled-NOT gates. We also show that the bottleneck in the efficiency of this repeater is due to detector losses

  20. The Enigma of Rapid Repeat Pregnancy: A Qualitative Study of Teen Mothers.

    Science.gov (United States)

    Conroy, K N; Engelhart, T G; Martins, Y; Huntington, N L; Snyder, A F; Coletti, K D; Cox, J E

    2016-06-01

    Rapid repeat pregnancy accounts for 18% of teen pregnancies and leads to adverse health, economic, and developmental outcomes for teen mothers and their children. Few interventions have been successful in reducing rapid repeat pregnancy. In this qualitative study we examined adolescent mothers' perceptions of their decision-making and behaviors that helped prevent or promote a rapid repeat pregnancy. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: Semistructured interviews were conducted with 31 adolescent mothers, aged 16-21 years; 15 of these subjects experienced a repeat pregnancy within a year of their first child's birth and 16 had not. Two researchers used a grounded, inductive technique to identify emergent themes; interviews were subsequently coded accordingly. Counts were tabulated of the number of times themes were endorsed among those with or without a repeat pregnancy. Four overarching themes emerged from the interviews: intentionality regarding pregnancy planning, patients' degree of independence in making contraceptive choices, sense of control over life experience, and barriers to follow-through on contraceptive planning. Teens who had not experienced a rapid repeat pregnancy more often endorsed themes of intentionality in preventing or promoting a pregnancy, independence in decision-making, and feelings of control over their experience. Ambivalence and lack of decision-making about seeking another pregnancy were frequently endorsed by mothers who had experienced a second pregnancy. Decision-making regarding seeking or preventing a rapid repeat pregnancy is complex for teen mothers; techniques to help support decision-making or to delay pregnancy until decision-repeat making is complete might be important in reducing rapid pregnancy. Copyright © 2015 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  1. Revisiting the TALE repeat.

    Science.gov (United States)

    Deng, Dong; Yan, Chuangye; Wu, Jianping; Pan, Xiaojing; Yan, Nieng

    2014-04-01

    Transcription activator-like (TAL) effectors specifically bind to double stranded (ds) DNA through a central domain of tandem repeats. Each TAL effector (TALE) repeat comprises 33-35 amino acids and recognizes one specific DNA base through a highly variable residue at a fixed position in the repeat. Structural studies have revealed the molecular basis of DNA recognition by TALE repeats. Examination of the overall structure reveals that the basic building block of TALE protein, namely a helical hairpin, is one-helix shifted from the previously defined TALE motif. Here we wish to suggest a structure-based re-demarcation of the TALE repeat which starts with the residues that bind to the DNA backbone phosphate and concludes with the base-recognition hyper-variable residue. This new numbering system is consistent with the α-solenoid superfamily to which TALE belongs, and reflects the structural integrity of TAL effectors. In addition, it confers integral number of TALE repeats that matches the number of bound DNA bases. We then present fifteen crystal structures of engineered dHax3 variants in complex with target DNA molecules, which elucidate the structural basis for the recognition of bases adenine (A) and guanine (G) by reported or uncharacterized TALE codes. Finally, we analyzed the sequence-structure correlation of the amino acid residues within a TALE repeat. The structural analyses reported here may advance the mechanistic understanding of TALE proteins and facilitate the design of TALEN with improved affinity and specificity.

  2. One-way quantum repeaters with quantum Reed-Solomon codes

    Science.gov (United States)

    Muralidharan, Sreraman; Zou, Chang-Ling; Li, Linshu; Jiang, Liang

    2018-05-01

    We show that quantum Reed-Solomon codes constructed from classical Reed-Solomon codes can approach the capacity on the quantum erasure channel of d -level systems for large dimension d . We study the performance of one-way quantum repeaters with these codes and obtain a significant improvement in key generation rate compared to previously investigated encoding schemes with quantum parity codes and quantum polynomial codes. We also compare the three generations of quantum repeaters using quantum Reed-Solomon codes and identify parameter regimes where each generation performs the best.

  3. Changes in Variable Number of Tandem Repeats in 'Candidatus Liberibacter asiaticus' through Insect Transmission.

    Directory of Open Access Journals (Sweden)

    Hiroshi Katoh

    Full Text Available Citrus greening (huanglongbing is the most destructive citrus disease worldwide. The disease is associated with three species of 'Candidatus Liberibacter' among which 'Ca. Liberibacter asiaticus' has the widest distribution. 'Ca. L. asiaticus' is commonly transmitted by a phloem-feeding insect vector, the Asian citrus psyllid Diaphorina citri. A previous study showed that isolates of 'Ca. L. asiaticus' were clearly differentiated by variable number of tandem repeat (VNTR profiles at four loci in the genome. In this study, the VNTR analysis was further validated by assessing the stability of these repeats after multiplication of the pathogen upon host-to-host transmission using a 'Ca. L. asiaticus' strain from Japan. The results showed that some tandem repeats showed detectable changes after insect transmission. To our knowledge, this is the first report to demonstrate that the repeat numbers VNTR 002 and 077 of 'Ca. L. asiaticus' change through psyllid transmission. VNTRs in the recipient plant were apparently unrelated to the growing phase of the vector. In contrast, changes in the number of tandem repeats increased with longer acquisition and inoculation access periods, whereas changes were not observed through psyllid transmission after relatively short acquisition and inoculation access periods, up to 20 and 19 days, respectively.

  4. Mechanism of Repeat-Associated MicroRNAs in Fragile X Syndrome

    Directory of Open Access Journals (Sweden)

    Karen Kelley

    2012-01-01

    Full Text Available The majority of the human genome is comprised of non-coding DNA, which frequently contains redundant microsatellite-like trinucleotide repeats. Many of these trinucleotide repeats are involved in triplet repeat expansion diseases (TREDs such as fragile X syndrome (FXS. After transcription, the trinucleotide repeats can fold into RNA hairpins and are further processed by Dicer endoribonuclases to form microRNA (miRNA-like molecules that are capable of triggering targeted gene-silencing effects in the TREDs. However, the function of these repeat-associated miRNAs (ramRNAs is unclear. To solve this question, we identified the first native ramRNA in FXS and successfully developed a transgenic zebrafish model for studying its function. Our studies showed that ramRNA-induced DNA methylation of the FMR1 5′-UTR CGG trinucleotide repeat expansion is responsible for both pathological and neurocognitive characteristics linked to the transcriptional FMR1 gene inactivation and the deficiency of its protein product FMRP. FMRP deficiency often causes synapse deformity in the neurons essential for cognition and memory activities, while FMR1 inactivation augments metabotropic glutamate receptor (mGluR-activated long-term depression (LTD, leading to abnormal neuronal responses in FXS. Using this novel animal model, we may further dissect the etiological mechanisms of TREDs, with the hope of providing insights into new means for therapeutic intervention.

  5. Studies on serum macro and micro minerals status in repeat breeder ...

    African Journals Online (AJOL)

    user01

    2014-03-05

    Mar 5, 2014 ... as well as 11.5% to gross domestic product. Repeat breeding is one of ... signs with no clinical detectable reproductive disorders. *Corresponding ... repeat breeding includes abnormal recommencement of postpartum ovarian ...

  6. RTEL1 Inhibits Trinucleotide Repeat Expansions and Fragility

    OpenAIRE

    Aisling Frizzell; Jennifer H.G. Nguyen; Mark I.R. Petalcorin; Katherine D. Turner; Simon J. Boulton; Catherine H. Freudenreich; Robert S. Lahue

    2014-01-01

    SUMMARY Human RTEL1 is an essential, multifunctional helicase that maintains telomeres, regulates homologous recombination, and helps prevent bone marrow failure. Here, we show that RTEL1 also blocks trinucleotide repeat expansions, the causal mutation for 17 neurological diseases. Increased expansion frequencies of (CTG·CAG) repeats occurred in human cells following knockdown of RTEL1, but not the alternative helicase Fbh1, and purified RTEL1 efficiently unwound triplet repeat hairpins in vi...

  7. Single, 14-Day, and 13-Week Repeated Dose Toxicity Studies of Daily Oral Gelidium elegans Extract Administration to Rats.

    Science.gov (United States)

    Choi, Jia; Ryu, Su-Jung; Kim, Kui-Jin; Kim, Hyung-Min; Chung, Hee-Chul; Lee, Boo-Yong

    2018-01-20

    Gelidium elegans extract (GEE) is derived from a red alga from the Asia-Pacific region, which has antioxidant, anti-adipogenic, and anti-hyperglycemic effects. However, detailed studies of the toxicology of GEE have not been performed. We evaluated the single oral dose toxicity of GEE in male and female Sprague-Dawley (CD) rats. GEE did not cause deaths or have toxic effects at dosages of 5000 mg/kg/day, although compound-colored stools and diarrhea were observed in both sexes, which lasted 5000 mg/kg. We next evaluated the repeated oral dose toxicity of GEE in CD rats over 14 days and 13 weeks. GEE did not induce any significant toxicological changes in either sex at 2000 mg/kg/day. Repeated oral dose toxicity studies showed no adverse effects, in terms of clinical signs, mortality, body mass, food consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy, organ masses, or histopathology, at dosages of 500, 1000, or 2000 mg/kg/day. The no observed adverse effect level (NOAEL) for GEE is thus likely to be >2000 mg/kg/day, and no pathology was identified in potential target organs. Therefore, this study indicates that repeated oral dosing with GEE is safe in CD rats.

  8. TALEN-Induced Double-Strand Break Repair of CTG Trinucleotide Repeats

    Directory of Open Access Journals (Sweden)

    Valentine Mosbach

    2018-02-01

    Full Text Available Trinucleotide repeat expansions involving CTG/CAG triplets are responsible for several neurodegenerative disorders, including myotonic dystrophy and Huntington’s disease. Because expansions trigger the disease, contracting repeat length could be a possible approach to gene therapy for these disorders. Here, we show that a TALEN-induced double-strand break was very efficient at contracting expanded CTG repeats in yeast. We show that RAD51, POL32, and DNL4 are dispensable for double-strand break repair within CTG repeats, the only required genes being RAD50, SAE2, and RAD52. Resection was totally abolished in the absence of RAD50 on both sides of the break, whereas it was reduced in a sae2Δ mutant on the side of the break containing the longest repeat tract, suggesting that secondary structures at double-strand break ends must be removed by the Mre11-Rad50 complex and Sae2. Following the TALEN double-strand break, single-strand annealing occurred between both sides of the repeat tract, leading to repeat contraction.

  9. Genus-specific protein binding to the large clusters of DNA repeats (short regularly spaced repeats) present in Sulfolobus genomes

    DEFF Research Database (Denmark)

    Peng, Xu; Brügger, Kim; Shen, Biao

    2003-01-01

    terminally modified and corresponds to SSO454, an open reading frame of previously unassigned function. It binds specifically to DNA fragments carrying double and single repeat sequences, binding on one side of the repeat structure, and producing an opening of the opposite side of the DNA structure. It also...... recognizes both main families of repeat sequences in S. solfataricus. The recombinant protein, expressed in Escherichia coli, showed the same binding properties to the SRSR repeat as the native one. The SSO454 protein exhibits a tripartite internal repeat structure which yields a good sequence match...... with a helix-turn-helix DNA-binding motif. Although this putative motif is shared by other archaeal proteins, orthologs of SSO454 were only detected in species within the Sulfolobus genus and in the closely related Acidianus genus. We infer that the genus-specific protein induces an opening of the structure...

  10. Receptionist input to quality and safety in repeat prescribing in UK general practice: ethnographic case study.

    Science.gov (United States)

    Swinglehurst, Deborah; Greenhalgh, Trisha; Russell, Jill; Myall, Michelle

    2011-11-03

    To describe, explore, and compare organisational routines for repeat prescribing in general practice to identify contributors and barriers to safety and quality. Ethnographic case study. Four urban UK general practices with diverse organisational characteristics using electronic patient records that supported semi-automation of repeat prescribing. 395 hours of ethnographic observation of staff (25 doctors, 16 nurses, 4 healthcare assistants, 6 managers, and 56 reception or administrative staff), and 28 documents and other artefacts relating to repeat prescribing locally and nationally. Potential threats to patient safety and characteristics of good practice. Observation of how doctors, receptionists, and other administrative staff contributed to, and collaborated on, the repeat prescribing routine. Analysis included mapping prescribing routines, building a rich description of organisational practices, and drawing these together through narrative synthesis. This was informed by a sociological model of how organisational routines shape and are shaped by information and communications technologies. Results Repeat prescribing was a complex, technology-supported social practice requiring collaboration between clinical and administrative staff, with important implications for patient safety. More than half of requests for repeat prescriptions were classed as "exceptions" by receptionists (most commonly because the drug, dose, or timing differed from what was on the electronic repeat list). They managed these exceptions by making situated judgments that enabled them (sometimes but not always) to bridge the gap between the idealised assumptions about tasks, roles, and interactions that were built into the electronic patient record and formal protocols, and the actual repeat prescribing routine as it played out in practice. This work was creative and demanded both explicit and tacit knowledge. Clinicians were often unaware of this input and it did not feature in policy

  11. Repeatability of visual acuity measurement.

    Science.gov (United States)

    Raasch, T W; Bailey, I L; Bullimore, M A

    1998-05-01

    This study investigates features of visual acuity chart design and acuity testing scoring methods which affect the validity and repeatability of visual acuity measurements. Visual acuity was measured using the Sloan and British Standard letter series, and Landolt rings. Identifiability of the different letters as a function of size was estimated, and expressed in the form of frequency-of-seeing curves. These functions were then used to simulate acuity measurements with a variety of chart designs and scoring criteria. Systematic relationships exist between chart design parameters and acuity score, and acuity score repeatability. In particular, an important feature of a chart, that largely determines the repeatability of visual acuity measurement, is the amount of size change attributed to each letter. The methods used to score visual acuity performance also affect repeatability. It is possible to evaluate acuity score validity and repeatability using the statistical principles discussed here.

  12. Intra-examiner repeatability and agreement in accommodative response measurements.

    Science.gov (United States)

    Antona, B; Sanchez, I; Barrio, A; Barra, F; Gonzalez, E

    2009-11-01

    Clinical measurement of the accommodative response (AR) identifies the focusing plane of a subject with respect to the accommodative target. To establish whether a significant change in AR has occurred, it is important to determine the repeatability of this measurement. This study had two aims: First, to determine the intraexaminer repeatability of AR measurements using four clinical methods: Nott retinoscopy, monocular estimate method (MEM) retinoscopy, binocular crossed cylinder test (BCC) and near autorefractometry. Second, to study the level of agreement between AR measurements obtained with the different methods. The AR of the right eye at one accommodative demand of 2.50 D (40 cm) was measured on two separate occasions in 61 visually normal subjects of mean age 19.7 years (range 18-32 years). The intraexaminer repeatability of the tests, and agreement between them, were estimated by the Bland-Altman method. We determined mean differences (MD) and the 95% limits of agreement [coefficient of repeatability (COR) and coefficient of agreement (COA)]. Nott retinoscopy and BCC offered the best repeatability, showing the lowest MD and narrowest 95% interval of agreement (Nott: -0.10 +/- 0.66 D, BCC: -0.05 +/- 0.75 D). The 95% limits of agreement for the four techniques were similar (COA = +/- 0.92 to +/-1.00 D) yet clinically significant, according to the expected values of the AR. The two dynamic retinoscopy techniques (Nott and MEM) had a better agreement (COA = +/-0.64 D) although this COA must be interpreted in the context of the low MEM repeatability (COR = +/-0.98 D). The best method of assessing AR was Nott retinoscopy. The BCC technique was also repeatable, and both are recommended as suitable methods for clinical use. Despite better agreement between MEM and Nott, agreement among the remaining methods was poor such that their interchangeable use in clinical practice is not recommended.

  13. FRB 121102: A Starquake-induced Repeater?

    Science.gov (United States)

    Wang, Weiyang; Luo, Rui; Yue, Han; Chen, Xuelei; Lee, Kejia; Xu, Renxin

    2018-01-01

    Since its initial discovery, the fast radio burst (FRB) FRB 121102 has been found to be repeating with millisecond-duration pulses. Very recently, 14 new bursts were detected by the Green Bank Telescope during its continuous monitoring observations. In this paper, we show that the burst energy distribution has a power-law form which is very similar to the Gutenberg–Richter law of earthquakes. In addition, the distribution of burst waiting time can be described as a Poissonian or Gaussian distribution, which is consistent with earthquakes, while the aftershock sequence exhibits some local correlations. These findings suggest that the repeating FRB pulses may originate from the starquakes of a pulsar. Noting that the soft gamma-ray repeaters (SGRs) also exhibit such distributions, the FRB could be powered by some starquake mechanisms associated with the SGRs, including the crustal activity of a magnetar or solidification-induced stress of a newborn strangeon star. These conjectures could be tested with more repeating samples.

  14. Prolonged Repeated Acupuncture Stimulation Induces Habituation Effects in Pain-Related Brain Areas: An fMRI Study

    Science.gov (United States)

    Li, Chuanfu; Yang, Jun; Park, Kyungmo; Wu, Hongli; Hu, Sheng; Zhang, Wei; Bu, Junjie; Xu, Chunsheng; Qiu, Bensheng; Zhang, Xiaochu

    2014-01-01

    Most previous studies of brain responses to acupuncture were designed to investigate the acupuncture instant effect while the cumulative effect that should be more important in clinical practice has seldom been discussed. In this study, the neural basis of the acupuncture cumulative effect was analyzed. For this experiment, forty healthy volunteers were recruited, in which more than 40 minutes of repeated acupuncture stimulation was implemented at acupoint Zhusanli (ST36). Three runs of acupuncture fMRI datasets were acquired, with each run consisting of two blocks of acupuncture stimulation. Besides general linear model (GLM) analysis, the cumulative effects of acupuncture were analyzed with analysis of covariance (ANCOVA) to find the association between the brain response and the cumulative duration of acupuncture stimulation in each stimulation block. The experimental results showed that the brain response in the initial stage was the strongest although the brain response to acupuncture was time-variant. In particular, the brain areas that were activated in the first block and the brain areas that demonstrated cumulative effects in the course of repeated acupuncture stimulation overlapped in the pain-related areas, including the bilateral middle cingulate cortex, the bilateral paracentral lobule, the SII, and the right thalamus. Furthermore, the cumulative effects demonstrated bimodal characteristics, i.e. the brain response was positive at the beginning, and became negative at the end. It was suggested that the cumulative effect of repeated acupuncture stimulation was consistent with the characteristic of habituation effects. This finding may explain the neurophysiologic mechanism underlying acupuncture analgesia. PMID:24821143

  15. Nifty Nines and Repeating Decimals

    Science.gov (United States)

    Brown, Scott A.

    2016-01-01

    The traditional technique for converting repeating decimals to common fractions can be found in nearly every algebra textbook that has been published, as well as in many precalculus texts. However, students generally encounter repeating decimal numerals earlier than high school when they study rational numbers in prealgebra classes. Therefore, how…

  16. Single and 2-week repeated intravenous dose toxicity studies of disodium mercaptoundecahydro-closo-dodecaborate in rats

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Fumio; Yabuuchi, Kazuya; Ohno, Kouji; Muraoka, Yoshihiro [Shionogi and Co. Ltd., Toyonaka, Osaka (Japan). Developmental Research Lab.; Ikeuchi, Isao

    1998-10-01

    Disodium mercaptoundecahydro-closo-dodecaborate (BSH) is a boron compound used in Boron Neutron Capture Therapy for malignant brain tumors. Intravenous single and 2-week repeated dose toxicity studies of BSH were performed in Sprague-Dawley rats. In the single-dose study, BSH was administered at doses of 100, 300 or 600 mg/kg. Death occurred within 10 min (acute type) or from 5 hr to 2 days (delayed type) after dosing in the 600 mg/kg group. No differences in mortality by sex and dosing speed were observed. Major causes of death were considered to be circulatory disorder in acute death and renal injury in delayed death. The renal injury was observed in the 300 and 600 mg/kg groups. In the 2-week repeated dose study, BSH was administered at doses of 30, 100 or 300 mg/kg/day for 14 days. Body weight gain was suppressed in the 100 and 300 mg/kg groups. One male in the 300 mg/kg group died due to renal and pulmonary lesions at day 8. Slight anemia was observed in the 300 mg/kg group. Pathologically, the kidney showed tubular regeneration with increase of weight in the 300 mg/kg. From these results, the NOAEL of BSH is 30 mg/kg/day. (author)

  17. A COMPARISON OF PAIRS FIGURE SKATERS IN REPEATED JUMPS

    Directory of Open Access Journals (Sweden)

    William A. Sands

    2012-03-01

    Full Text Available Trends in pairs figure skating have shown that increasingly difficult jumps have become an essential aspect of high-level performance, especially in the latter part of a competitive program. We compared a repeated jump power index in a 60 s repeated jump test to determine the relationship of repeated jump test to competitive rank and to measure 2D hip, knee, and ankle angles and angular velocities at 0, 20, 40, and 60 s. Eighteen National Team Pairs Figure Skaters performed a 60 s repeated jump test on a large switch-mat with timing of flight and ground durations and digital video recording. Each 60-s period was divided into 6, 10-s intervals, with power indexes (W/kg calculated for each 10-s interval. Power index by 10-s interval repeated measures ANOVAs (RMANOVA showed that males exceeded females at all intervals, and the highest power index interval was during 10 to 20 s for both sexes. RMANOVAs of angles and angular velocities showed main effects for time only. Power index and jumping techniques among figure skaters showed rapid and steady declines over the test duration. Power index can predict approximately 50% of competitive rank variance, and sex differences in jumping technique were rare

  18. Flanking Variation Influences Rates of Stutter in Simple Repeats

    Directory of Open Access Journals (Sweden)

    August E. Woerner

    2017-11-01

    Full Text Available It has been posited that the longest uninterrupted stretch (LUS of tandem repeats, as defined by the number of exactly matching repeating motif units, is a better predictor of rates of stutter than the parental allele length (PAL. While there are cases where this hypothesis is likely correct, such as the 9.3 allele in the TH01 locus, there can be situations where it may not apply as well. For example, the PAL may capture flanking indel variations while remaining insensitive to polymorphisms in the repeat, and these haplotypic changes may impact the stutter rate. To address this, rates of stutter were contrasted against the LUS as well as the PAL on different flanking haplotypic backgrounds. This study shows that rates of stutter can vary substantially depending on the flanking haplotype, and while there are cases where the LUS is a better predictor of stutter than the PAL, examples to the contrary are apparent in commonly assayed forensic markers. Further, flanking variation that is 7 bp from the repeat region can impact rates of stutter. These findings suggest that non-proximal effects, such as DNA secondary structure, may be impacting the rates of stutter in common forensic short tandem repeat markers.

  19. Single, 14-Day, and 13-Week Repeated Dose Toxicity Studies of Daily Oral Gelidium elegans Extract Administration to Rats

    Directory of Open Access Journals (Sweden)

    Jia Choi

    2018-01-01

    Full Text Available Gelidium elegans extract (GEE is derived from a red alga from the Asia–Pacific region, which has antioxidant, anti-adipogenic, and anti-hyperglycemic effects. However, detailed studies of the toxicology of GEE have not been performed. We evaluated the single oral dose toxicity of GEE in male and female Sprague-Dawley (CD rats. GEE did not cause deaths or have toxic effects at dosages of 5000 mg/kg/day, although compound-colored stools and diarrhea were observed in both sexes, which lasted <2 days. Therefore, the LD50 of GEE is likely to be >5000 mg/kg. We next evaluated the repeated oral dose toxicity of GEE in CD rats over 14 days and 13 weeks. GEE did not induce any significant toxicological changes in either sex at 2000 mg/kg/day. Repeated oral dose toxicity studies showed no adverse effects, in terms of clinical signs, mortality, body mass, food consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy, organ masses, or histopathology, at dosages of 500, 1000, or 2000 mg/kg/day. The no observed adverse effect level (NOAEL for GEE is thus likely to be >2000 mg/kg/day, and no pathology was identified in potential target organs. Therefore, this study indicates that repeated oral dosing with GEE is safe in CD rats.

  20. Repeat immigration: A previously unobserved source of heterogeneity?

    Science.gov (United States)

    Aradhya, Siddartha; Scott, Kirk; Smith, Christopher D

    2017-07-01

    Register data allow for nuanced analyses of heterogeneities between sub-groups which are not observable in other data sources. One heterogeneity for which register data is particularly useful is in identifying unique migration histories of immigrant populations, a group of interest across disciplines. Years since migration is a commonly used measure of integration in studies seeking to understand the outcomes of immigrants. This study constructs detailed migration histories to test whether misclassified migrations may mask important heterogeneities. In doing so, we identify a previously understudied group of migrants called repeat immigrants, and show that they differ systematically from permanent immigrants. In addition, we quantify the degree to which migration information is misreported in the registers. The analysis is carried out in two steps. First, we estimate income trajectories for repeat immigrants and permanent immigrants to understand the degree to which they differ. Second, we test data validity by cross-referencing migration information with changes in income to determine whether there are inconsistencies indicating misreporting. From the first part of the analysis, the results indicate that repeat immigrants systematically differ from permanent immigrants in terms of income trajectories. Furthermore, income trajectories differ based on the way in which years since migration is calculated. The second part of the analysis suggests that misreported migration events, while present, are negligible. Repeat immigrants differ in terms of income trajectories, and may differ in terms of other outcomes as well. Furthermore, this study underlines that Swedish registers provide a reliable data source to analyze groups which are unidentifiable in other data sources.

  1. Repeat Colonoscopy within 6 Months after Initial Outpatient Colonoscopy in Ontario: A Population-Based Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Lawrence Paszat

    2017-01-01

    Full Text Available Background. The goal of this study is to examine utilization of early repeat colonoscopy ≤ 6 months after an index procedure. Methods. We identified persons having repeat colonoscopy ≤ 6 months following outpatient colonoscopy without prior colonoscopy ≤ 5 years or prior diagnosis of colorectal cancer (CRC. We modeled repeat colonoscopy using a generalized estimating equation with an exchangeable correlation structure to account for clustering of patients by endoscopist. Results. The population included 334,663 persons, 7,892 (2.36% of whom had an early repeat colonoscopy within 6 months. Overall, endoscopist prior year colonoscopy volume was inversely related to repeat ≤ 6 months. Repeat colonoscopy ≤ 6 months varied by the clinical setting of the index colonoscopy (adjusted OR = 1.41 (95% CI 1.29–1.55 at nonhospital facilities compared to teaching or community hospitals. Among those who had polypectomy or biopsy, the adjusted OR for early repeat ≤ 6 months was elevated among those whose index colonoscopy was at a nonhospital facility (OR 1.44, 95% CI 1.30–1.60, compared to those at a teaching hospital or community hospital. Conclusions. Repeat colonoscopy ≤ 6 months after an index procedure is associated with the clinical setting of the index colonoscopy.

  2. [Study on causes and treatment of repeated vulvovaginitis in girlhood].

    Science.gov (United States)

    Zhang, Di-kai; Li, Xiu-yun; Yang, Dong-zi; Kuang, Jian-quan

    2006-07-01

    To explore the causes and treatment of repeated vulvovaginitis in girlhood in order to improve its prevention and treatment. Fifty-one girls with repeated vulvovaginitis (age vulvovaginitis and 14 ones (27%) suffering from posterior recto-vaginal fistula with in 51 patients. Five girls (10%) were smitten with vulval ulcer and 3 ones (6%) had been were found with vaginal foreign bodies. One girl (2%) was smitten with adhesion of labia minora. The vaginal discharges taken from 21 girls were cultured. Seventeen cases found bacteria. The positive rate of bacteria culture in the 21 cases reached 81%, in which, E.coli accounted for 5 cases (24%), staphylococcus and streptococcus accounted for 3 cases (14%) respectively. Patients suffering from non-specific vulvovaginitis and vulval ulcer accepted external lotion, antibiotic ointment or combining with antibiotics. Patients suffering from posterior recto-vaginal fistula accepted fistulectomy. Three girls who found vaginal foreign bodies took out of foreign bodies by hysteroscope. Fifty-one girls all were cured after appropriate therapy. Vulvovaginitis is the most common gynecologic diagnosis in girlhood. The principal cause of repeated invasion is non-specific vulvovaginitis and the secondly one is posterior recto-vaginal fistula. It need overhaul during the diagnosis. It is very availability to use hysteroscopy and do bacteria culture + antibiotic sensitivity test for repeated pediatric vulvovaginitis.

  3. Beverage Intake Assessment Questionnaire: Relative Validity and Repeatability in a Spanish Population with Metabolic Syndrome from the PREDIMED-PLUS Study

    Science.gov (United States)

    Ferreira-Pêgo, Cíntia; Nissensohn, Mariela; Kavouras, Stavros A.; Babio, Nancy; Serra-Majem, Lluís; Martín Águila, Adys; Mauromoustakos, Andy; Álvarez Pérez, Jacqueline; Salas-Salvadó, Jordi

    2016-01-01

    We assess the repeatability and relative validity of a Spanish beverage intake questionnaire for assessing water intake from beverages. The present analysis was performed within the framework of the PREDIMED-PLUS trial. The study participants were adults (aged 55–75) with a BMI ≥27 and <40 kg/m2, and at least three components of Metabolic Syndrome (MetS). A trained dietitian completed the questionnaire. Participants provided 24-h urine samples, and the volume and urine osmolality were recorded. The repeatability of the baseline measurement at 6 and 1 year was examined by paired Student’s t-test comparisons. A total of 160 participants were included in the analysis. The Bland–Altman analysis showed relatively good agreement between total daily fluid intake assessed using the fluid-specific questionnaire, and urine osmolality and 24-h volume with parameter estimates of −0.65 and 0.22, respectively (R2 = 0.20; p < 0.001). In the repeatability test, no significant differences were found between neither type of beverage nor total daily fluid intake at 6 months and 1-year assessment, compared to baseline. The proposed fluid-specific assessment questionnaire designed to assess the consumption of water and other beverages in Spanish adult individuals was found to be relatively valid with good repeatability. PMID:27483318

  4. Fostering repeat donations in Ghana.

    Science.gov (United States)

    Owusu-Ofori, S; Asenso-Mensah, K; Boateng, P; Sarkodie, F; Allain, J-P

    2010-01-01

    Most African countries are challenged in recruiting and retaining voluntary blood donors by cost and other complexities and in establishing and implementing national blood policies. The availability of replacement donors who are a cheaper source of blood has not enhanced repeat voluntary donor initiatives. An overview of activities for recruiting and retaining voluntary blood donors was carried out. Donor records from mobile sessions were reviewed from 2002 to 2008. A total of 71,701 blood donations; 45,515 (63.5%) being voluntary donations with 11,680 (25%) repeat donations were collected during the study period. Donations from schools and colleges contributed a steady 60% of total voluntary whilst radio station blood drives increased contribution from 10 to 27%. Though Muslim population is less than 20%, blood collection was above the 30-donation cost-effectiveness threshold with a repeat donation trend reaching 60%. In contrast Christian worshippers provided donations. Repeat donation trends amongst school donors and radio blood drives were 20% and 70% respectively. Repeat donations rates have been variable amongst different blood donor groups in Kumasi, Ghana. The impact of community leaders in propagating altruism cannot be overemphasized. Programs aiming at motivating replacement donors to be repeat donors should be developed and assessed. Copyright 2009 The International Association for Biologicals. All rights reserved.

  5. Comparative study of radioprotective properties of serotin derivatives repeatedly applied before gamma irradiation

    International Nuclear Information System (INIS)

    Gorelova, N.V.; Antipov, V.V.; Vasin, M.V.

    1977-01-01

    In the experiments on albino mice, the phenomenon of desensitization has been studied by a specific activity and some pharmacologic properties of serotonin, mexamin and 5-acetyloxytryptamine, the time-intervals between injections of the preparations being 5, 30 and 60 minutes, 2, 3, 4, 6, 8 and 24 hours. A correlation has been found between changes in radioprotective and pharmacologic properties (as determined by the accumulation of the dye in the splenic tissue) after repeated administration of mexamin. The phenomenon of desensitization is probably dependent not only on the chemical nature and mechanism of action of the protectors but also on the conditions under which they are repeatedly applied

  6. [Computer optical topography: a study of the repeatability of the results of human body model examination].

    Science.gov (United States)

    Sarnadskiĭ, V N

    2007-01-01

    The problem of repeatability of the results of examination of a plastic human body model is considered. The model was examined in 7 positions using an optical topograph for kyphosis diagnosis. The examination was performed under television camera monitoring. It was shown that variation of the model position in the camera view affected the repeatability of the results of topographic examination, especially if the model-to-camera distance was changed. A study of the repeatability of the results of optical topographic examination can help to increase the reliability of the topographic method, which is widely used for medical screening of children and adolescents.

  7. Measurements of Repeated Tightening and Loosening Torque of Seven Different Implant/Abutment Connection Designs and Their Modifications: An In Vitro Study.

    Science.gov (United States)

    Butkevica, Alena; Nathanson, Dan; Pober, Richard; Strating, Herman

    2018-02-01

    Repeated tightening and loosening of the abutment screw may alter its mechanical and physical properties affecting the optimal torque and ultimate reliability of an implant/abutment connection. The purpose of this study was to evaluate the effect of repeated tightening and loosening of implant/abutment screws on the loosening torque of implant/abutment connections of commercially available implant systems. Seven different implant/abutment connections and their modifications were tested. The screws of each system were tightened according to the manufacturer's specifications. After 20 minutes the screws were loosened. This procedure was repeated ten times, and the differences between the 1st and 10th cycle were expressed as a percentage change RTq(%) and correlated with initial torque, the number of threads, the length of shank, and thread surface area employing Spearman's analysis. All systems showed significant differences in residual torque (RTq) value (p 0.05). All connections but group 3 (p = 1.000) showed a significant change from the initial torque (ITq) to the RTq values. The first successive RTq values increased in two connection groups 1 and 2. The remaining connections showed reduced RTq values ranging from -1.2 % (group 5) to -23.5% (group 6). The RTq values declined gradually with every repeated tightening in groups 1, 2, 3, 8, 9, 11, 12. In group 2, after the tenth tightening the RTq was still above the ITq value. Only length of shank demonstrated a correlation with the RTq(%) change over the successive tightening loosening cycles (p abutment screws caused varying torque level changes among the different systems. These observations can probably be attributed to connection design. Limiting the number of tightening/loosening cycles in clinical and laboratory procedures is advisable for most of the implant systems tested. © 2016 by the American College of Prosthodontists.

  8. Factors influencing repeated teenage pregnancy: a review and meta-analysis.

    Science.gov (United States)

    Maravilla, Joemer C; Betts, Kim S; Couto E Cruz, Camila; Alati, Rosa

    2017-11-01

    Existing evidence of predictors of repeated teenage pregnancy has not been assessed rigorously. This systematic review provides a comprehensive evaluation of protective and risk factors that are associated with repeated teenage pregnancy through a metaanalytical consensus. We used PubMed, EMBASE, CINAHL, ProQuest, PsychINFO, ScienceDirect, Scopus, and Web of Science databases from 1997-2015 and the reference list of other relevant research papers and related reviews. Eligibility criteria included (1) epidemiologic studies that analyzed factors associated with repeated pregnancy or birth among adolescents pregnancy, and (2) experimental studies with an observational component that was adjusted for the intervention. We performed narrative synthesis of study characteristics, participant characteristics, study results, and quality assessment. We also conducted random-effects and quality-effects metaanalyses with meta-regression to obtain pooled odds ratios of identified factors and to determine sources of between-study heterogeneity. Twenty-six eligible epidemiologic studies, most from the United States (n=24), showed >47 factors with no evidence of publication bias for each metaanalysis. Use of contraception (pooled odds ratio, 0.60; 95% confidence interval, 0.35-1.02), particularly long-acting reversible contraceptives (pooled odds ratio, 0.19; 95% confidence interval, 0.08-0.45), considerably reduced repeated teenage pregnancy risk. Among studies about contraception, the number of follow-up visits (adjusted coefficient, 0.72; P=.102) and country of study (unadjusted coefficient, 2.57; permuted P=.071) explained between-study heterogeneity. Education-related factors, which included higher level of education (pooled odds ratio, 0.74; 95% confidence interval, 0.60-0.91) and school continuation (pooled odds ratio, 0.53; 95% confidence interval, 0.33-0.84), were found to be protective. Conversely, depression (pooled odds ratio, 1.46; 95% confidence interval, 1

  9. ACCA phosphopeptide recognition by the BRCT repeats of BRCA1.

    Science.gov (United States)

    Ray, Hind; Moreau, Karen; Dizin, Eva; Callebaut, Isabelle; Venezia, Nicole Dalla

    2006-06-16

    The tumour suppressor gene BRCA1 encodes a 220 kDa protein that participates in multiple cellular processes. The BRCA1 protein contains a tandem of two BRCT repeats at its carboxy-terminal region. The majority of disease-associated BRCA1 mutations affect this region and provide to the BRCT repeats a central role in the BRCA1 tumour suppressor function. The BRCT repeats have been shown to mediate phospho-dependant protein-protein interactions. They recognize phosphorylated peptides using a recognition groove that spans both BRCT repeats. We previously identified an interaction between the tandem of BRCA1 BRCT repeats and ACCA, which was disrupted by germ line BRCA1 mutations that affect the BRCT repeats. We recently showed that BRCA1 modulates ACCA activity through its phospho-dependent binding to ACCA. To delineate the region of ACCA that is crucial for the regulation of its activity by BRCA1, we searched for potential phosphorylation sites in the ACCA sequence that might be recognized by the BRCA1 BRCT repeats. Using sequence analysis and structure modelling, we proposed the Ser1263 residue as the most favourable candidate among six residues, for recognition by the BRCA1 BRCT repeats. Using experimental approaches, such as GST pull-down assay with Bosc cells, we clearly showed that phosphorylation of only Ser1263 was essential for the interaction of ACCA with the BRCT repeats. We finally demonstrated by immunoprecipitation of ACCA in cells, that the whole BRCA1 protein interacts with ACCA when phosphorylated on Ser1263.

  10. Tools for analyzing genetic variants from sequencing data Case study: short tandem repeats

    OpenAIRE

    Gymrek, Melissa

    2016-01-01

    This was presented as a BitesizeBio Webinar entitled "Tools for analyzing genetic variants from sequencing data Case study: short tandem repeats"Accompanying scripts can be accessed on github:https://github.com/mgymrek/mgymrek-bitesizebio-webinar 

  11. RTEL1 Inhibits Trinucleotide Repeat Expansions and Fragility

    Directory of Open Access Journals (Sweden)

    Aisling Frizzell

    2014-03-01

    Full Text Available Human RTEL1 is an essential, multifunctional helicase that maintains telomeres, regulates homologous recombination, and helps prevent bone marrow failure. Here, we show that RTEL1 also blocks trinucleotide repeat expansions, the causal mutation for 17 neurological diseases. Increased expansion frequencies of (CTG⋅CAG repeats occurred in human cells following knockdown of RTEL1, but not the alternative helicase Fbh1, and purified RTEL1 efficiently unwound triplet repeat hairpins in vitro. The expansion-blocking activity of RTEL1 also required Rad18 and HLTF, homologs of yeast Rad18 and Rad5. These findings are reminiscent of budding yeast Srs2, which inhibits expansions, unwinds hairpins, and prevents triplet-repeat-induced chromosome fragility. Accordingly, we found expansions and fragility were suppressed in yeast srs2 mutants expressing RTEL1, but not Fbh1. We propose that RTEL1 serves as a human analog of Srs2 to inhibit (CTG⋅CAG repeat expansions and fragility, likely by unwinding problematic hairpins.

  12. Repeatability of regional myocardial blood flow calculation in 82Rb PET imaging

    International Nuclear Information System (INIS)

    Knešaurek, Karin; Machac, Josef; Zhang, Zhuangyu

    2009-01-01

    We evaluated the repeatability of the calculation of myocardial blood flow (MBF) at rest and pharmacological stress, and calculated the coronary flow reserve (CFR) utilizing 82 Rb PET imaging. The aim of the research was to prove high repeatability for global MBF and CFR values and good repeatability for regional MBF and CFR values. The results will have significant impact on cardiac PET imaging in terms of making it more affordable and increasing its use. 12 normal volunteers were imaged at rest and during pharmacological stress, with 2220 MBq of 82 Rb each. A GE Advance PET system was used to acquire dynamic 50-frame studies. MBF was calculated with a 2-compartmental model using a modified PMOD program (PMOD; University Hospital Zurich, Zurich, Switzerland). Two differential equations, describing a 2-compartmental model, were solved by numerical integration and using Levenberg-Marquardt's method for fitting data. The PMOD program defines 16 standard segments and calculates myocardial flow for each segment, as well as average septal, anterior, lateral, inferior and global flow. Repeatability was evaluated according to the method of Bland and Altman. Global rest and stress MBF, as well as global CFR, showed very good repeatability. No significant differences were found between the paired resting global MBF (0.63 ± 0.13 vs. 0.64 ± 0.13 mL/min/g; mean difference, -1.0% ± 2.6%) and the stress global MBF (1.37 ± 0.23 vs. 1.37 ± 0.24; mean difference, 0.1% ± 2.3%). Global CFR was highly reproducible (2.25 ± 0.56 vs. 2.22 ± 0.54, P = not statistically significant; mean difference, 1.3% ± 14.3%). Repeatability coefficients for global rest MBF were 0.033 (5.2%) and stress MBF 0.062 (4.5%) mL/min/g. Regional rest and stress MBF and CFR have shown good reproducibility. The average per sector repeatability coefficients for rest MBF were 0.056 (8.5%) and stress MBF 0.089 (6.3%) mL/min/g, and average repeatability coefficient for CFR was 0.25 (10.6%). The results

  13. Incremental Dynamic Analysis of Koyna Dam under Repeated Ground Motions

    Science.gov (United States)

    Zainab Nik Azizan, Nik; Majid, Taksiah A.; Nazri, Fadzli Mohamed; Maity, Damodar; Abdullah, Junaidah

    2018-03-01

    This paper discovers the incremental dynamic analysis (IDA) of concrete gravity dam under single and repeated earthquake loadings to identify the limit state of the dam. Seven ground motions with horizontal and vertical direction as seismic input considered in the nonlinear dynamic analysis based on the real repeated earthquake in the worldwide. All the ground motions convert to respond spectrum and scaled according to the developed elastic respond spectrum in order to match the characteristic of the ground motion to the soil type. The scaled was depends on the fundamental period, T1 of the dam. The Koyna dam has been selected as a case study for the purpose of the analysis by assuming that no sliding and rigid foundation, has been estimated. IDA curves for Koyna dam developed for single and repeated ground motions and the performance level of the dam identifies. The IDA curve of repeated ground motion shown stiffer rather than single ground motion. The ultimate state displacement for a single event is 45.59mm and decreased to 39.33mm under repeated events which are decreased about 14%. This showed that the performance level of the dam based on seismic loadings depend on ground motion pattern.

  14. Nonparametric additive regression for repeatedly measured data

    KAUST Repository

    Carroll, R. J.

    2009-05-20

    We develop an easily computed smooth backfitting algorithm for additive model fitting in repeated measures problems. Our methodology easily copes with various settings, such as when some covariates are the same over repeated response measurements. We allow for a working covariance matrix for the regression errors, showing that our method is most efficient when the correct covariance matrix is used. The component functions achieve the known asymptotic variance lower bound for the scalar argument case. Smooth backfitting also leads directly to design-independent biases in the local linear case. Simulations show our estimator has smaller variance than the usual kernel estimator. This is also illustrated by an example from nutritional epidemiology. © 2009 Biometrika Trust.

  15. Interstitial telomere-like repeats in the Arabidopsis thaliana genome.

    Science.gov (United States)

    Uchida, Wakana; Matsunaga, Sachihiro; Sugiyama, Ryuji; Kawano, Shigeyuki

    2002-02-01

    Eukaryotic chromosomal ends are protected by telomeres, which are thought to play an important role in ensuring the complete replication of chromosomes. On the other hand, non-functional telomere-like repeats in the interchromosomal regions (interstitial telomeric repeats; ITRs) have been reported in several eukaryotes. In this study, we identified eight ITRs in the Arabidopsis thaliana genome, each consisting of complete and degenerate 300- to 1200-bp sequences. The ITRs were grouped into three classes (class IA-B, class II, and class IIIA-E) based on the degeneracy of the telomeric repeats in ITRs. The telomeric repeats of the two ITRs in class I were conserved for the most part, whereas the single ITR in class II, and the five ITRs in class III were relatively degenerated. In addition, degenerate ITRs were surrounded by common sequences that shared 70-100% homology to each other; these are named ITR-adjacent sequences (IAS). Although the genomic regions around ITRs in class I lacked IAS, those around ITRs in class II contained IAS (IASa), and those around five ITRs in class III had nine types of IAS (IASb, c, d, e, f, g, h, i, and j). Ten IAS types in classes II and III showed no significant homology to each other. The chromosomal locations of ITRs and IAS were not category-related, but most of them were adjacent to, or part of, a centromere. These results show that the A. thaliana genome has undergone chromosomal rearrangements, such as end-fusions and segmental duplications.

  16. Trinucleotide repeat microsatellite markers for Black Poplar (Populus nigra L.)

    NARCIS (Netherlands)

    Smulders, M.J.M.; Schoot, van der J.; Arens, P.; Vosman, B.

    2001-01-01

    Using an enrichment procedure, we have cloned microsatellite repeats from black poplar (Populus nigra L.) and developed primers for microsatellite marker analysis. Ten primer pairs, mostly for trinucleotide repeats, produced polymorphic fragments in P. nigra. Some of them also showed amplification

  17. Implementation of repeat HIV testing during pregnancy in Kenya: a qualitative study.

    Science.gov (United States)

    Rogers, Anna Joy; Weke, Elly; Kwena, Zachary; Bukusi, Elizabeth A; Oyaro, Patrick; Cohen, Craig R; Turan, Janet M

    2016-07-11

    Repeat HIV testing in late pregnancy has the potential to decrease rates of mother-to-child transmission of HIV by identifying mothers who seroconvert after having tested negative for HIV in early pregnancy. Despite being national policy in Kenya, the available data suggest that implementation rates are low. We conducted 20 in-depth semi-structured interviews with healthcare providers and managers to explore barriers and enablers to implementation of repeat HIV testing guidelines for pregnant women. Participants were from the Nyanza region of Kenya and were purposively selected to provide variation in socio-demographics and job characteristics. Interview transcripts were coded and analyzed in Dedoose software using a thematic analysis approach. Four themes were identified a priori using Ferlie and Shortell's Framework for Change and additional themes were allowed to emerge from the data. Participants identified barriers and enablers at the client, provider, facility, and health system levels. Key barriers at the client level from the perspective of providers included late initial presentation to antenatal care and low proportions of women completing the recommended four antenatal visits. Barriers to offering repeat HIV testing for providers included heavy workloads, time limitations, and failing to remember to check for retest eligibility. At the facility level, inconsistent volume of clients and lack of space required for confidential HIV retesting were cited as barriers. Finally, at the health system level, there were challenges relating to the HIV test kit supply chain and the design of nationally standardized antenatal patient registers. Enablers to improving the implementation of repeat HIV testing included client dissemination of the benefits of antenatal care through word-of-mouth, provider cooperation and task shifting, and it was suggested that use of an electronic health record system could provide automatic reminders for retest eligibility. This study

  18. Viral delivery of C9orf72 hexanucleotide repeat expansions in mice leads to repeat-length-dependent neuropathology and behavioural deficits

    Directory of Open Access Journals (Sweden)

    Saul Herranz-Martin

    2017-07-01

    Full Text Available Intronic GGGGCC repeat expansions in C9orf72 are the most common genetic cause of amyotrophic lateral sclerosis (ALS and frontotemporal dementia (FTD. Two major pathologies stemming from the hexanucleotide RNA expansions (HREs have been identified in postmortem tissue: intracellular RNA foci and repeat-associated non-ATG dependent (RAN dipeptides, although it is unclear how these and other hallmarks of disease contribute to the pathophysiology of neuronal injury. Here, we describe two novel lines of mice that overexpress either 10 pure or 102 interrupted GGGGCC repeats mediated by adeno-associated virus (AAV and recapitulate the relevant human pathology and disease-related behavioural phenotypes. Similar levels of intracellular RNA foci developed in both lines of mice, but only mice expressing 102 repeats generated C9orf72 RAN pathology, neuromuscular junction (NMJ abnormalities, dispersal of the hippocampal CA1, enhanced apoptosis, and deficits in gait and cognition. Neither line of mice, however, showed extensive TAR DNA-binding protein 43 (TDP-43 pathology or neurodegeneration. Our data suggest that RNA foci pathology is not a good predictor of C9orf72 RAN dipeptide formation, and that RAN dipeptides and NMJ dysfunction are drivers of C9orf72 disease pathogenesis. These AAV-mediated models of C9orf72-associated ALS/FTD will be useful tools for studying disease pathophysiology and developing new therapeutic approaches.

  19. Improvement of Repeated-Sprint Ability and Horizontal-Jumping Performance in Elite Young Basketball Players With Low-Volume Repeated-Maximal-Power Training.

    Science.gov (United States)

    Gonzalo-Skok, Oliver; Tous-Fajardo, Julio; Arjol-Serrano, José Luis; Suarez-Arrones, Luis; Casajús, José Antonio; Mendez-Villanueva, Alberto

    2016-05-01

    To examine the effects of a low-volume repeated-power-ability (RPA) training program on repeated-sprint and change-of- direction (COD) ability and functional jumping performance. Twenty-two male elite young basketball players (age 16.2 ± 1.2 y, height 190.0 ± 10.0 cm, body mass 82.9 ± 10.1 kg) were randomly assigned either to an RPA-training group (n = 11) or a control group (n = 11). RPA training consisted of leg-press exercise, twice a week for 6 wk, of 1 or 2 blocks of 5 sets × 5 repetitions with 20 s of passive recovery between sets and 3 min between blocks with the load that maximized power output. Before and after training, performance was assessed by a repeated-sprint-ability (RSA) test, a repeated-COD-ability test, a hop for distance, and a drop jump followed by tests of a double unilateral hop with the right and left legs. Within-group and between-groups differences showed substantial improvements in slowest (RSAs) and mean time (RSAm) on RSA; best, slowest and mean time on repeated-COD ability; and unilateral right and left hop in the RPA group in comparison with control. While best time on RSA showed no improvement in any group, there was a large relationship (r = .68, 90% CI .43;.84) between the relative decrement in RSAm and RSAs, suggesting better sprint maintenance with RPA training. The relative improvements in best and mean repeated-COD ability were very largely correlated (r = .89, 90% CI .77;.94). Six weeks of lowvolume (4-14 min/wk) RPA training improved several physical-fitness tests in basketball players.

  20. A Unified Model for Repeating and Non-repeating Fast Radio Bursts

    International Nuclear Information System (INIS)

    Bagchi, Manjari

    2017-01-01

    The model that fast radio bursts (FRBs) are caused by plunges of asteroids onto neutron stars can explain both repeating and non-repeating bursts. If a neutron star passes through an asteroid belt around another star, there would be a series of bursts caused by a series of asteroid impacts. Moreover, the neutron star would cross the same belt repetitively if it were in a binary with the star hosting the asteroid belt, leading to a repeated series of bursts. I explore the properties of neutron star binaries that could lead to the only known repeating FRB so far (FRB121102). In this model, the next two epochs of bursts are expected around 2017 February 27 and 2017 December 18. On the other hand, if the asteroid belt is located around the neutron star itself, then a chance fall of an asteroid from that belt onto the neutron star would lead to a non-repeating burst. Even a neutron star grazing an asteroid belt can lead to a non-repeating burst caused by just one asteroid plunge during the grazing. This is possible even when the neutron star is in a binary with the asteroid-hosting star, if the belt and the neutron star orbit are non-coplanar.

  1. A Unified Model for Repeating and Non-repeating Fast Radio Bursts

    Energy Technology Data Exchange (ETDEWEB)

    Bagchi, Manjari, E-mail: manjari@imsc.res.in [The Institute of Mathematical Sciences (IMSc-HBNI), 4th Cross Road, CIT Campus, Taramani, Chennai 600113 (India)

    2017-04-01

    The model that fast radio bursts (FRBs) are caused by plunges of asteroids onto neutron stars can explain both repeating and non-repeating bursts. If a neutron star passes through an asteroid belt around another star, there would be a series of bursts caused by a series of asteroid impacts. Moreover, the neutron star would cross the same belt repetitively if it were in a binary with the star hosting the asteroid belt, leading to a repeated series of bursts. I explore the properties of neutron star binaries that could lead to the only known repeating FRB so far (FRB121102). In this model, the next two epochs of bursts are expected around 2017 February 27 and 2017 December 18. On the other hand, if the asteroid belt is located around the neutron star itself, then a chance fall of an asteroid from that belt onto the neutron star would lead to a non-repeating burst. Even a neutron star grazing an asteroid belt can lead to a non-repeating burst caused by just one asteroid plunge during the grazing. This is possible even when the neutron star is in a binary with the asteroid-hosting star, if the belt and the neutron star orbit are non-coplanar.

  2. Repeatability of Cryogenic Multilayer Insulation

    Science.gov (United States)

    Johnson, W. L.; Vanderlaan, M.; Wood, J. J.; Rhys, N. O.; Guo, W.; Van Sciver, S.; Chato, D. J.

    2017-12-01

    Due to the variety of requirements across aerospace platforms, and one off projects, the repeatability of cryogenic multilayer insulation (MLI) has never been fully established. The objective of this test program is to provide a more basic understanding of the thermal performance repeatability of MLI systems that are applicable to large scale tanks. There are several different types of repeatability that can be accounted for: these include repeatability between identical blankets, repeatability of installation of the same blanket, and repeatability of a test apparatus. The focus of the work in this report is on the first two types of repeatability. Statistically, repeatability can mean many different things. In simplest form, it refers to the range of performance that a population exhibits and the average of the population. However, as more and more identical components are made (i.e. the population of concern grows), the simple range morphs into a standard deviation from an average performance. Initial repeatability testing on MLI blankets has been completed at Florida State University. Repeatability of five Glenn Research Center (GRC) provided coupons with 25 layers was shown to be +/- 8.4% whereas repeatability of repeatedly installing a single coupon was shown to be +/- 8.0%. A second group of 10 coupons has been fabricated by Yetispace and tested by Florida State University, the repeatability between coupons has been shown to be +/- 15-25%. Based on detailed statistical analysis, the data has been shown to be statistically significant.

  3. Psychological Processes and Repeat Suicidal Behavior: A Four-Year Prospective Study

    Science.gov (United States)

    2013-01-01

    Objective: Although suicidal behavior is a major public health concern, understanding of individually sensitive suicide risk mechanisms is limited. In this study, the authors investigated, for the first time, the utility of defeat and entrapment in predicting repeat suicidal behavior in a sample of suicide attempters. Method: Seventy patients hospitalized after a suicide attempt completed a range of clinical and psychological measures (depression, hopelessness, suicidal ideation, defeat, and entrapment) while in hospital. Four years later, a nationally linked database was used to determine who had been hospitalized again after a suicide attempt. Results: Over 4 years, 24.6% of linked participants were readmitted to hospital after a suicidal attempt. In univariate logistic regression analyses, defeat and entrapment as well as depression, hopelessness, past suicide attempts, and suicidal ideation all predicted suicidal behavior over this interval. However, in the multivariate analysis, entrapment and past frequency of suicide attempts were the only significant predictors of suicidal behavior. Conclusions: This longitudinal study supports the utility of a new theoretical model in the prediction of suicidal behavior. Individually sensitive suicide risk processes like entrapment could usefully be targeted in treatment interventions to reduce the risk of repeat suicidal behavior in those who have been previously hospitalized after a suicide attempt. PMID:23855989

  4. RTEL1 inhibits trinucleotide repeat expansions and fragility.

    Science.gov (United States)

    Frizzell, Aisling; Nguyen, Jennifer H G; Petalcorin, Mark I R; Turner, Katherine D; Boulton, Simon J; Freudenreich, Catherine H; Lahue, Robert S

    2014-03-13

    Human RTEL1 is an essential, multifunctional helicase that maintains telomeres, regulates homologous recombination, and helps prevent bone marrow failure. Here, we show that RTEL1 also blocks trinucleotide repeat expansions, the causal mutation for 17 neurological diseases. Increased expansion frequencies of (CTG⋅CAG) repeats occurred in human cells following knockdown of RTEL1, but not the alternative helicase Fbh1, and purified RTEL1 efficiently unwound triplet repeat hairpins in vitro. The expansion-blocking activity of RTEL1 also required Rad18 and HLTF, homologs of yeast Rad18 and Rad5. These findings are reminiscent of budding yeast Srs2, which inhibits expansions, unwinds hairpins, and prevents triplet-repeat-induced chromosome fragility. Accordingly, we found expansions and fragility were suppressed in yeast srs2 mutants expressing RTEL1, but not Fbh1. We propose that RTEL1 serves as a human analog of Srs2 to inhibit (CTG⋅CAG) repeat expansions and fragility, likely by unwinding problematic hairpins. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Repeated vertebral augmentation for new vertebral compression fractures of postvertebral augmentation patients: a nationwide cohort study

    Directory of Open Access Journals (Sweden)

    Liang CL

    2015-03-01

    Full Text Available Cheng-Loong Liang,1 Hao-Kwan Wang,1 Fei-Kai Syu,2 Kuo-Wei Wang,1 Kang Lu,1 Po-Chou Liliang1 1Department of Neurosurgery, E-Da Hospital, I-Shou University, Kaohsiung City, Taiwan; 2Department of Pharmacy, China Medical University Hospital, Taichung City, Taiwan Purpose: Postvertebral augmentation vertebral compression fractures are common; repeated vertebral augmentation is usually performed for prompt pain relief. This study aimed to evaluate the incidence and risk factors of repeat vertebral augmentation.Methods: We performed a retrospective, nationwide, population-based longitudinal observation study, using the National Health Insurance Research Database (NHIRD of Taiwan. All patients who received vertebral augmentation for vertebral compression fractures were evaluated. The collected data included patient characteristics (demographics, comorbidities, and medication exposure and repeat vertebral augmentation. Kaplan–Meier and stratified Cox proportional hazard regressions were performed for analyses.Results: The overall incidence of repeat vertebral augmentation was 11.3% during the follow-up until 2010. Patients with the following characteristics were at greater risk for repeat vertebral augmentation: female sex (AOR=1.24; 95% confidence interval [CI]: 1.10–2.36, advanced age (AOR=1.60; 95% CI: 1.32–2.08, diabetes mellitus (AOR=4.31; 95% CI: 4.05–5.88, cerebrovascular disease (AOR=4.09; 95% CI: 3.44–5.76, dementia (AOR=1.97; 95% CI: 1.69–2.33, blindness or low vision (AOR=3.72; 95% CI: 2.32–3.95, hypertension (AOR=2.58; 95% CI: 2.35–3.47, and hyperlipidemia (AOR=2.09; 95% CI: 1.67–2.22. Patients taking calcium/ vitamin D (AOR=2.98; 95% CI: 1.83–3.93, bisphosphonates (AOR=2.11; 95% CI: 1.26–2.61, or calcitonin (AOR=4.59; 95% CI: 3.40–5.77 were less likely to undergo repeat vertebral augmentation; however, those taking steroids (AOR=7.28; 95% CI: 6.32–8.08, acetaminophen (AOR=3.54; 95% CI: 2.75–4.83, or nonsteroidal

  6. Deployment Repeatability

    Science.gov (United States)

    2016-04-01

    evaluating the deployment repeatability builds upon the testing or analysis of deployment kinematics (Chapter 6) and adds repetition. Introduction...material yield or failure during a test. For the purposes of this chapter, zero shift will refer to permanent changes in the structure, while reversible ...the content of other chapters in this book: Gravity Compensation (Chapter 4) and Deployment Kinematics and Dynamics (Chapter 6). Repeating the

  7. Primary blast survival and injury risk assessment for repeated blast exposures.

    Science.gov (United States)

    Panzer, Matthew B; Bass, Cameron R Dale; Rafaels, Karin A; Shridharani, Jay; Capehart, Bruce P

    2012-02-01

    The widespread use of explosives by modern insurgents and terrorists has increased the potential frequency of blast exposure in soldiers and civilians. This growing threat highlights the importance of understanding and evaluating blast injury risk and the increase of injury risk from exposure to repeated blast effects. Data from more than 3,250 large animal experiments were collected from studies focusing on the effects of blast exposure. The current study uses 2,349 experiments from the data collection for analysis of the primary blast injury and survival risk for both long- and short-duration blasts, including the effects from repeated exposures. A piecewise linear logistic regression was performed on the data to develop survival and injury risk assessment curves. New injury risk assessment curves uniting long- and short-duration blasts were developed for incident and reflected pressure measures and were used to evaluate the risk of injury based on blast over pressure, positive-phase duration, and the number of repeated exposures. The risk assessments were derived for three levels of injury severity: nonauditory, pulmonary, and fatality. The analysis showed a marked initial decrease in injury tolerance with each subsequent blast exposure. This effect decreases with increasing number of blast exposures. The new injury risk functions showed good agreement with the existing experimental data and provided a simplified model for primary blast injury risk. This model can be used to predict blast injury or fatality risk for single exposure and repeated exposure cases and has application in modern combat scenarios or in setting occupational health limits. .Copyright © 2012 by Lippincott Williams & Wilkins

  8. MNS16A tandem repeat minisatellite of human telomerase gene: functional studies in colorectal, lung and prostate cancer.

    Science.gov (United States)

    Hofer, Philipp; Zöchmeister, Cornelia; Behm, Christian; Brezina, Stefanie; Baierl, Andreas; Doriguzzi, Angelina; Vanas, Vanita; Holzmann, Klaus; Sutterlüty-Fall, Hedwig; Gsur, Andrea

    2017-04-25

    MNS16A, a functional polymorphic tandem repeat minisatellite, is located in the promoter region of an antisense transcript of the human telomerase reverse transcriptase gene. MNS16A promoter activity depends on the variable number of tandem repeats (VNTR) presenting varying numbers of transcription factor binding sites for GATA binding protein 1. Although MNS16A has been investigated in multiple cancer epidemiology studies with incongruent findings, functional data of only two VNTRs (VNTR-243 and VNTR-302) were available thus far, linking the shorter VNTR to higher promoter activity.For the first time, we investigated promoter activity of all six VNTRs of MNS16A in cell lines of colorectal, lung and prostate cancer using Luciferase reporter assay. In all investigated cell lines shorter VNTRs showed higher promoter activity. While this anticipated indirect linear relationship was affirmed for colorectal cancer SW480 (P = 0.006), a piecewise linear regression model provided significantly better model fit in lung cancer A-427 (P = 6.9 × 10-9) and prostate cancer LNCaP (P = 0.039). In silico search for transcription factor binding sites in MNS16A core repeat element suggested a higher degree of complexity involving X-box binding protein 1, general transcription factor II-I, and glucocorticoid receptor alpha in addition to GATA binding protein 1.Further functional studies in additional cancers are requested to extend our knowledge of MNS16A functionality uncovering potential cancer type-specific differences. Risk alleles may vary in different malignancies and their determination in vitro could be relevant for interpretation of genotype data.

  9. Digital repeat analysis; setup and operation.

    Science.gov (United States)

    Nol, J; Isouard, G; Mirecki, J

    2006-06-01

    Since the emergence of digital imaging, there have been questions about the necessity of continuing reject analysis programs in imaging departments to evaluate performance and quality. As a marketing strategy, most suppliers of digital technology focus on the supremacy of the technology and its ability to reduce the number of repeats, resulting in less radiation doses given to patients and increased productivity in the department. On the other hand, quality assurance radiographers and radiologists believe that repeats are mainly related to positioning skills, and repeat analysis is the main tool to plan training needs to up-skill radiographers. A comparative study between conventional and digital imaging was undertaken to compare outcomes and evaluate the need for reject analysis. However, digital technology still being at its early development stages, setting a credible reject analysis program became the major task of the study. It took the department, with the help of the suppliers of the computed radiography reader and the picture archiving and communication system, over 2 years of software enhancement to build a reliable digital repeat analysis system. The results were supportive of both philosophies; the number of repeats as a result of exposure factors was reduced dramatically; however, the percentage of repeats as a result of positioning skills was slightly on the increase for the simple reason that some rejects in the conventional system qualifying for both exposure and positioning errors were classified as exposure error. The ability of digitally adjusting dark or light images reclassified some of those images as positioning errors.

  10. The repeatability of three diagnostic methods (visual using ICDAS II, laser fluorescence, and radiographic) for early caries detection

    Science.gov (United States)

    Sukmasari, S.; Lestari, W.; Ko, B. B.; Noh, Z.; Asmail, N.; Yaacob, N.

    2017-08-01

    Newly introduced ICDAS II as a visual method, laser fluorescence as another technique that have ability to quantify early mineral loss of tooth structure and intra oral radiograph, are methods can be used in the clinic. To provide standardization for comprehensive caries management at an early stage, all methods supposed to be tested between users. The objective of this research is to evaluate the repeatability of each system. It is a comparative cross sectional study using 100 extracted permanent teeth without obvious cavitation (premolar & molar) that were collected and stored in thymol solution. The teeth were embedded on the wax block and labeled with numbers. All 5 surfaces were examined by 5 examiners using visual (ICDAS II), laser fluorescence (LF) and radiographic examination. The data were then analyzed to measure intra and inter examiner repeatability using Cronbach’s alpha and inter-item correlation matrix. Intra-examiner repeatability for all examiners was >0.7. Chronbach’s a value for inter-examiner repeatability for ICDAS II was >0.8 on 3 surfaces except on buccal and lingual. LF exhibit repeatability of >0.8 on all surfaces. Radiograph shows a low value of inter examiner repeatability (students for inter-item correlation while the 2nd and 3rd reading of LF displays the best agreement. ICDAS II score favors more non-invasive treatment compared to LF. ICDAS II showed good repeatability except on buccal and lingual surfaces. In line with some of the previous study, ICDAS II is applicable for caries detection in daily clinical basis. Laser fluorescence exhibits the highest repeatability while the radiograph showed weak inter-examiner repeatability. Treatment decisions of ICDAS II propose more preventive treatment for early caries lesions compared to laser fluorescence.

  11. A repeating fast radio burst.

    Science.gov (United States)

    Spitler, L G; Scholz, P; Hessels, J W T; Bogdanov, S; Brazier, A; Camilo, F; Chatterjee, S; Cordes, J M; Crawford, F; Deneva, J; Ferdman, R D; Freire, P C C; Kaspi, V M; Lazarus, P; Lynch, R; Madsen, E C; McLaughlin, M A; Patel, C; Ransom, S M; Seymour, A; Stairs, I H; Stappers, B W; van Leeuwen, J; Zhu, W W

    2016-03-10

    Fast radio bursts are millisecond-duration astronomical radio pulses of unknown physical origin that appear to come from extragalactic distances. Previous follow-up observations have failed to find additional bursts at the same dispersion measure (that is, the integrated column density of free electrons between source and telescope) and sky position as the original detections. The apparent non-repeating nature of these bursts has led to the suggestion that they originate in cataclysmic events. Here we report observations of ten additional bursts from the direction of the fast radio burst FRB 121102. These bursts have dispersion measures and sky positions consistent with the original burst. This unambiguously identifies FRB 121102 as repeating and demonstrates that its source survives the energetic events that cause the bursts. Additionally, the bursts from FRB 121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and which vary on timescales of minutes or less. Although there may be multiple physical origins for the population of fast radio bursts, these repeat bursts with high dispersion measure and variable spectra specifically seen from the direction of FRB 121102 support an origin in a young, highly magnetized, extragalactic neutron star.

  12. The effect of repeated testing vs repeated practice on skills learning in undergraduate dental education.

    Science.gov (United States)

    Sennhenn-Kirchner, S; Goerlich, Y; Kirchner, B; Notbohm, M; Schiekirka, S; Simmenroth, A; Raupach, T

    2018-02-01

    Recent studies in undergraduate medical education have demonstrated the advantage of repeated testing over repeated practice with regard to knowledge and skills retention. The aim of this study was to investigate whether this "testing effect" also applies to skills retention in undergraduate dental education. In this prospective, randomised controlled trial, fourth-year dental students at Göttingen University Medical Centre participated in a training session on surgical suturing in winter term 2014/2015. Following this, they were either assigned to two sessions of additional skills training (group A) or two sessions of skills assessment with feedback (group B). These sessions were spaced over a period of 4 weeks. Skills retention was assessed in a summative objective structured clinical examination (OSCE) at the end of term, that is 6 months after the initial teaching session. A total of 32 students completed the study. With regard to suturing, OSCE performance was significantly better in group B than group A (81.9±13.1% vs 63.0±15.4%; P=0.001; Cohen's d=1.33). There was no significant OSCE performance difference in the two groups with regard to other learning objectives that were addressed in the end-of-term examination. Thus, the group difference was specific to suturing skills. This is the first study to demonstrate that in dental education, repeated testing produces more favourable skills retention than repeated practice. Test-enhanced learning might be a viable concept for skills retention in undergraduate dentistry education. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Discrepancies in autobiographical memories— implications for the assessment of asylum seekers: repeated interviews study

    Science.gov (United States)

    Herlihy, Jane; Scragg, Peter; Turner, Stuart

    2002-01-01

    Objective To investigate the consistency of autobiographical memory of people seeking asylum, in light of the assumption that discrepancies in asylum seekers' accounts of persecution mean that they are fabricating their stories. Design Repeated interviews. Setting England, 1999 and 2000. Participants Community sample of 27 Kosovan and 12 Bosnian refugees. Main outcome measures Discrepancies in repeated descriptions of one traumatic and one non-traumatic event, including specific details, rated as central or peripheral to the event. Self report measures of post-traumatic stress disorder and depression. Results Discrepancies between an individual's accounts were common. For participants with high levels of post-traumatic stress, the number of discrepancies increased with length of time between interviews. More discrepancies occurred in details peripheral to the account than in details that were central to the account. Conclusion The assumption that inconsistency of recall means that accounts have poor credibility is questionable. Discrepancies are likely to occur in repeated interviews. For refugees showing symptoms of high levels of post-traumatic stress, the length of the application process may also affect the number of discrepancies. Recall of details rated by the interviewee as peripheral to the account is more likely to be inconsistent than recall of details that are central to the account. Thus, such inconsistencies should not be relied on as indicating a lack of credibility. What is already known on this topicDiscrepancies between accounts of an event are often used to judge the credibility of asylum seekersWhat this study addsDiscrepancies arise between two accounts of the same event even when there is no reason for fabricationRefugees with high levels of post-traumatic stress are more likely to give inconsistent accounts if they have a long time to wait between interviewsInterviewees are more likely to be inconsistent in details that they rate as peripheral

  14. Potential Role of the Last Half Repeat in TAL Effectors Revealed by a Molecular Simulation Study

    Directory of Open Access Journals (Sweden)

    Hua Wan

    2016-01-01

    Full Text Available TAL effectors (TALEs contain a modular DNA-binding domain that is composed of tandem repeats. In all naturally occurring TALEs, the end of tandem repeats is invariantly a truncated half repeat. To investigate the potential role of the last half repeat in TALEs, we performed comparative molecular dynamics simulations for the crystal structure of DNA-bound TALE AvrBs3 lacking the last half repeat and its modeled structure having the last half repeat. The structural stability analysis indicates that the modeled system is more stable than the nonmodeled system. Based on the principle component analysis, it is found that the AvrBs3 increases its structural compactness in the presence of the last half repeat. The comparison of DNA groove parameters of the two systems implies that the last half repeat also causes the change of DNA major groove binding efficiency. The following calculation of hydrogen bond reveals that, by stabilizing the phosphate binding with DNA at the C-terminus, the last half repeat helps to adopt a compact conformation at the protein-DNA interface. It further mediates more contacts between TAL repeats and DNA nucleotide bases. Finally, we suggest that the last half repeat is required for the high-efficient recognition of DNA by TALE.

  15. Replication Stalling and Heteroduplex Formation within CAG/CTG Trinucleotide Repeats by Mismatch Repair

    KAUST Repository

    Viterbo, David; Michoud, Gregoire; Mosbach, Valentine; Dujon, Bernard; Richard, Guy-Franck

    2016-01-01

    Trinucleotide repeat expansions are responsible for at least two dozen neurological disorders. Mechanisms leading to these large expansions of repeated DNA are still poorly understood. It was proposed that transient stalling of the replication fork by the repeat tract might trigger slippage of the newly-synthesized strand over its template, leading to expansions or contractions of the triplet repeat. However, such mechanism was never formally proven. Here we show that replication fork pausing and CAG/CTG trinucleotide repeat instability are not linked, stable and unstable repeats exhibiting the same propensity to stall replication forks when integrated in a yeast natural chromosome. We found that replication fork stalling was dependent on the integrity of the mismatch-repair system, especially the Msh2p-Msh6p complex, suggesting that direct interaction of MMR proteins with secondary structures formed by trinucleotide repeats in vivo, triggers replication fork pauses. We also show by chromatin immunoprecipitation that Msh2p is enriched at trinucleotide repeat tracts, in both stable and unstable orientations, this enrichment being dependent on MSH3 and MSH6. Finally, we show that overexpressing MSH2 favors the formation of heteroduplex regions, leading to an increase in contractions and expansions of CAG/CTG repeat tracts during replication, these heteroduplexes being dependent on both MSH3 and MSH6. These heteroduplex regions were not detected when a mutant msh2-E768A gene in which the ATPase domain was mutated was overexpressed. Our results unravel two new roles for mismatch-repair proteins: stabilization of heteroduplex regions and transient blocking of replication forks passing through such repeats. Both roles may involve direct interactions between MMR proteins and secondary structures formed by trinucleotide repeat tracts, although indirect interactions may not be formally excluded.

  16. Replication Stalling and Heteroduplex Formation within CAG/CTG Trinucleotide Repeats by Mismatch Repair

    KAUST Repository

    Viterbo, David

    2016-03-16

    Trinucleotide repeat expansions are responsible for at least two dozen neurological disorders. Mechanisms leading to these large expansions of repeated DNA are still poorly understood. It was proposed that transient stalling of the replication fork by the repeat tract might trigger slippage of the newly-synthesized strand over its template, leading to expansions or contractions of the triplet repeat. However, such mechanism was never formally proven. Here we show that replication fork pausing and CAG/CTG trinucleotide repeat instability are not linked, stable and unstable repeats exhibiting the same propensity to stall replication forks when integrated in a yeast natural chromosome. We found that replication fork stalling was dependent on the integrity of the mismatch-repair system, especially the Msh2p-Msh6p complex, suggesting that direct interaction of MMR proteins with secondary structures formed by trinucleotide repeats in vivo, triggers replication fork pauses. We also show by chromatin immunoprecipitation that Msh2p is enriched at trinucleotide repeat tracts, in both stable and unstable orientations, this enrichment being dependent on MSH3 and MSH6. Finally, we show that overexpressing MSH2 favors the formation of heteroduplex regions, leading to an increase in contractions and expansions of CAG/CTG repeat tracts during replication, these heteroduplexes being dependent on both MSH3 and MSH6. These heteroduplex regions were not detected when a mutant msh2-E768A gene in which the ATPase domain was mutated was overexpressed. Our results unravel two new roles for mismatch-repair proteins: stabilization of heteroduplex regions and transient blocking of replication forks passing through such repeats. Both roles may involve direct interactions between MMR proteins and secondary structures formed by trinucleotide repeat tracts, although indirect interactions may not be formally excluded.

  17. Metamemory judgments and the benefits of repeated study: improving recall predictions through the activation of appropriate knowledge.

    Science.gov (United States)

    Tiede, Heather L; Leboe, Jason P

    2009-05-01

    Correspondence between judgments of learning (JOLs) and actual recall tends to be poor when the same items are studied and recalled multiple times (e.g., A. Koriat, L. Sheffer, & H. Ma'ayan, 2002). The authors investigated whether making relevant metamemory knowledge more salient would improve the association between actual and predicted recall as a function of repeated exposure to the same study list. In 2 experiments, participants completed 4 study-recall phases involving the same list of items. In addition to having participants make item-by-item JOLs during each study phase, after the 1st study-recall phase participants also generated change-in-recall estimates as to how many more or fewer words they would recall given another exposure to the same study list. This estimation procedure was designed to highlight repeated study as a factor that can contribute to recall performance. Activating metamemory knowledge about the benefits of repeated study for recall in this way allowed participants to accurately express this knowledge in a free-recall context (Experiment 2), but less so when the memory test was cued recall (Experiment 1). Copyright 2009 APA, all rights reserved.

  18. Costly renegotiation in repeated Bertand games

    DEFF Research Database (Denmark)

    Andersson, Ola; Wengström, Erik Roland

    2010-01-01

    This paper extends the concept of weak renegotiation-proof equilibrium (WRP) to allow for costly renegotiation and shows that even small renegotiation costs can have dramatic effects on the set of equilibria. More specifically, the paper analyzes the infinitely repeated Bertrand game. It is shown...

  19. Selection of body sway parameters according to their sensitivity and repeatability

    Directory of Open Access Journals (Sweden)

    Nejc Sarabon

    2010-03-01

    Full Text Available For the precise evaluation of body balance, static type of tests performed on a force plate are the most commonly used ones. In these tests, body sway characteristics are analyzed based on the model of inverted pendulum and looking at the center of pressure (COP movement in time. Human body engages different strategies to compensate for balance perturbations. For this reason, there is a need to identify parameters which are sensitive to specific balance changes and which enable us to identify balance sub-components. The aim of our study was to investigate intra-visit repeatability and sensibility of the 40 different body sway parameters. Twenty-nine subjects participated in the study. They performed three different balancing tasks of different levels of difficulty, three repetitions each. The hip-width parallel stance and the single leg stance, both with open eyes, were used as ways to compare different balance intensities due to biomechanical changes. Additionally, deprivation of vision was used in the third balance task to study sensitivity to sensory system changes. As shown by intraclass correlation coefficient (ICC, repeatability of cumulative parameters such as COP, maximal amplitude and frequency showed excellent repeatability (ICC>0,85. Other parameters describing sub-dynamics through single repetition proved to have unsatisfying repeatability. Parameters most sensitive to increased intensity of balancing tasks were common COP, COP in medio-lateral and in antero-posterior direction, and maximal amplitues in the same directions. Frequency of oscilations has proved to be sensitive only to deprivation of vision. As shown in our study, cumulative parameters describing the path which the center of pressure makes proved to be the most repeatable and sensitive to detect different increases of balancing tasks enabling future use in balance studies and in clinical practice.

  20. [Bioinformatics Analysis of Clustered Regularly Interspaced Short Palindromic Repeats in the Genomes of Shigella].

    Science.gov (United States)

    Wang, Pengfei; Wang, Yingfang; Duan, Guangcai; Xue, Zerun; Wang, Linlin; Guo, Xiangjiao; Yang, Haiyan; Xi, Yuanlin

    2015-04-01

    This study was aimed to explore the features of clustered regularly interspaced short palindromic repeats (CRISPR) structures in Shigella by using bioinformatics. We used bioinformatics methods, including BLAST, alignment and RNA structure prediction, to analyze the CRISPR structures of Shigella genomes. The results showed that the CRISPRs existed in the four groups of Shigella, and the flanking sequences of upstream CRISPRs could be classified into the same group with those of the downstream. We also found some relatively conserved palindromic motifs in the leader sequences. Repeat sequences had the same group with corresponding flanking sequences, and could be classified into two different types by their RNA secondary structures, which contain "stem" and "ring". Some spacers were found to homologize with part sequences of plasmids or phages. The study indicated that there were correlations between repeat sequences and flanking sequences, and the repeats might act as a kind of recognition mechanism to mediate the interaction between foreign genetic elements and Cas proteins.

  1. ATXN2 trinucleotide repeat length correlates with risk of ALS.

    Science.gov (United States)

    Sproviero, William; Shatunov, Aleksey; Stahl, Daniel; Shoai, Maryam; van Rheenen, Wouter; Jones, Ashley R; Al-Sarraj, Safa; Andersen, Peter M; Bonini, Nancy M; Conforti, Francesca L; Van Damme, Philip; Daoud, Hussein; Del Mar Amador, Maria; Fogh, Isabella; Forzan, Monica; Gaastra, Ben; Gellera, Cinzia; Gitler, Aaron D; Hardy, John; Fratta, Pietro; La Bella, Vincenzo; Le Ber, Isabelle; Van Langenhove, Tim; Lattante, Serena; Lee, Yi-Chung; Malaspina, Andrea; Meininger, Vincent; Millecamps, Stéphanie; Orrell, Richard; Rademakers, Rosa; Robberecht, Wim; Rouleau, Guy; Ross, Owen A; Salachas, Francois; Sidle, Katie; Smith, Bradley N; Soong, Bing-Wen; Sorarù, Gianni; Stevanin, Giovanni; Kabashi, Edor; Troakes, Claire; van Broeckhoven, Christine; Veldink, Jan H; van den Berg, Leonard H; Shaw, Christopher E; Powell, John F; Al-Chalabi, Ammar

    2017-03-01

    We investigated a CAG trinucleotide repeat expansion in the ATXN2 gene in amyotrophic lateral sclerosis (ALS). Two new case-control studies, a British dataset of 1474 ALS cases and 567 controls, and a Dutch dataset of 1328 ALS cases and 691 controls were analyzed. In addition, to increase power, we systematically searched PubMed for case-control studies published after 1 August 2010 that investigated the association between ATXN2 intermediate repeats and ALS. We conducted a meta-analysis of the new and existing studies for the relative risks of ATXN2 intermediate repeat alleles of between 24 and 34 CAG trinucleotide repeats and ALS. There was an overall increased risk of ALS for those carrying intermediate sized trinucleotide repeat alleles (odds ratio 3.06 [95% confidence interval 2.37-3.94]; p = 6 × 10 -18 ), with an exponential relationship between repeat length and ALS risk for alleles of 29-32 repeats (R 2  = 0.91, p = 0.0002). No relationship was seen for repeat length and age of onset or survival. In contrast to trinucleotide repeat diseases, intermediate ATXN2 trinucleotide repeat expansion in ALS does not predict age of onset but does predict disease risk. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  2. Characteristics of intergenerational contractions of the CTG repeat in myotonic dystropy

    Energy Technology Data Exchange (ETDEWEB)

    Ashizawa, T.; Anvret, M.; Grandell, U.; Baiget, M.; Cobo, A.M.; Barcelo, J.M.; Korneluk, R.G.; Dallapiccola, B.; Novelli, G.; Fenwick, R.G. Jr. (and others)

    1994-03-01

    In myotonic dystropy (DM), the size of a CTG repeat in the DM kinase gene generally increases in successive generations with clinical evidence of anticipation. However, there have also been cases with an intergenerational contraction of the repeat. The authors have examined 1,489 DM parent-offspring pairs, of which 95 (6.4%) showed such contractions in peripheral blood leukocytes (PBL). In 56 of th 95 pairs, clinical data allowed an analysis of their anticipation status. It is surprising that anticipation occurred in 27 (48%) of these 56 pairs, while none clearly showed a later onset of DM in the asymptomatic offspring. The contraction occurred in 76 (10%) of 753 paternal transmission and in 19 (3%) of 736 maternal transmissions. Anticipation was observed more frequently in maternal (85%) than in paternal (37%) transmissions (P<.001). The parental repeat size correlated with the size of intergenerational contraction (r[sup 2] = .50, P [much lt].001), and the slope of linear regression was steeper in paternal ([minus].62) than in maternal ([minus].30) transmissions (P [much lt].001). Sixteen DM parents had multiple DM offspring with the CTG repeat contractions. This frequency was higher than the frequency expected from the probability of the repeat contractions (6.4%) and the size of DM sib population (1.54 DM offspring per DM parent, in 968 DM parents). The authors conclude that (1) intergenerational contraction of the CTG repeat in leukocyte DNA frequently accompanies apparent anticipation, especially when DM is maternally transmitted, and (2) the paternal origin of the repeat and the presence of the repeat contraction in a sibling increase the probability of the CTG repeat contraction. 43 refs., 1 fig., 4 tabs.

  3. Study of simple sequence repeat (SSR) polymorphism for biotic ...

    African Journals Online (AJOL)

    home

    2013-10-02

    Oct 2, 2013 ... G. Siva Kumar1, K. Aruna Kumari1*, Ch. V. Durga Rani1, R. M. Sundaram2, S. Vanisree3, Md. ..... review by Jena and Mackill (2008) provided the list of .... repeat protein and is a member of a resistance gene cluster on rice.

  4. [A case-control study of factors associated with repeat teen pregnancy based on a sample from a university maternity hospital].

    Science.gov (United States)

    Silva, Andréa de Albuquerque Arruda; Coutinho, Isabela C; Katz, Leila; Souza, Alex Sandro Rolland

    2013-03-01

    Repeat teen pregnancy is a frequent issue and is considered an aggravating factor for increased maternal and fetal morbidity and social problems. The aim of the study was to identify factors associated with repeat teen pregnancy. A case-control study was conducted in 90 postpartum adolescents with more than one pregnancy (cases) and 90 adult women with a history of only one pregnancy during adolescence (controls). Statistical analysis used hierarchical logistic regression with 5% significance. Early sexual initiation (pregnancy (pregnancy, while partner change was inversely associated. Repeat teen pregnancy was mainly associated with reproductive and socioeconomic factors. Partner change appeared as a protective factor. Measures should be adopted during the postpartum period of teenage mothers in order to avoid repeat pregnancy.

  5. Who Repeats Algebra, and How Does Initial Performance Relate to Improvement When the Course Is Repeated?

    Science.gov (United States)

    Fong, Anthony; Jaquet, Karina; Finkelstein, Neal

    2016-01-01

    The information provided in this report shows how students perform when they repeat algebra I and how the level of improvement varies depending on initial course performance and the academic measure (course grades or CST scores). This information can help inform decisions and policies regarding whether and under what circumstances students should…

  6. The repeatability and reproducibility of the BioRID IIg in a repeatable laboratory seat based on a production car seat.

    Science.gov (United States)

    Hynd, David; Depinet, Paul; Lorenz, Bernd

    2013-01-01

    The United Nations Economic Commission for Europe Informal Group on GTR No. 7 Phase 2 are working to define a build level for the BioRID II rear impact (whiplash) crash test dummy that ensures repeatable and reproducible performance in a test procedure that has been proposed for future legislation. This includes the specification of dummy hardware, as well as the development of comprehensive certification procedures for the dummy. This study evaluated whether the dummy build level and certification procedures deliver the desired level of repeatability and reproducibility. A custom-designed laboratory seat was made using the seat base, back, and head restraint from a production car seat to ensure a representative interface with the dummy. The seat back was reinforced for use in multiple tests and the recliner mechanism was replaced by an external spring-damper mechanism. A total of 65 tests were performed with 6 BioRID IIg dummies using the draft GTR No.7 sled pulse and seating procedure. All dummies were subject to the build, maintenance, and certification procedures defined by the Informal Group. The test condition was highly repeatable, with a very repeatable pulse, a well-controlled seat back response, and minimal observed degradation of seat foams. The results showed qualitatively reasonable repeatability and reproducibility for the upper torso and head accelerations, as well as for T1 Fx and upper neck Fx . However, reproducibility was not acceptable for T1 and upper neck Fz or for T1 and upper neck My . The Informal Group has not selected injury or seat assessment criteria for use with BioRID II, so it is not known whether these channels would be used in the regulation. However, the ramping-up behavior of the dummy showed poor reproducibility, which would be expected to affect the reproducibility of dummy measurements in general. Pelvis and spine characteristics were found to significantly influence the dummy measurements for which poor reproducibility was

  7. The leucine-rich repeat structure.

    Science.gov (United States)

    Bella, J; Hindle, K L; McEwan, P A; Lovell, S C

    2008-08-01

    The leucine-rich repeat is a widespread structural motif of 20-30 amino acids with a characteristic repetitive sequence pattern rich in leucines. Leucine-rich repeat domains are built from tandems of two or more repeats and form curved solenoid structures that are particularly suitable for protein-protein interactions. Thousands of protein sequences containing leucine-rich repeats have been identified by automatic annotation methods. Three-dimensional structures of leucine-rich repeat domains determined to date reveal a degree of structural variability that translates into the considerable functional versatility of this protein superfamily. As the essential structural principles become well established, the leucine-rich repeat architecture is emerging as an attractive framework for structural prediction and protein engineering. This review presents an update of the current understanding of leucine-rich repeat structure at the primary, secondary, tertiary and quaternary levels and discusses specific examples from recently determined three-dimensional structures.

  8. Repeatability and relative validity of a quantitative food-frequency questionnaire among French adults

    Directory of Open Access Journals (Sweden)

    Emmanuel Barrat

    2012-10-01

    Full Text Available Background: A 50-item self-administered food frequency questionnaire (FFQ was developed for French adults, to assess the intake of energy, 10 macronutrients, 11 vitamins, and 11 minerals, and to be used in the context of a medical consultation. Objective: To assess the repeatability and relative validity of this FFQ compared to a 7-day diet record (7-DR. Design: A total of 54 and 100 French adults were included in the repeatability and validation studies, respectively. Repeatability was assessed using two FFQs, the second carried out 3 weeks after the first. In the validation study, subjects first completed the FFQ, then the 7-DR the following week. Energy and nutrient intakes were compared using Pearson correlation. The degree of misclassification by the FFQ, compared to the 7-DR, was calculated by a contingency table of quintiles. Bland–Altman plots assessed the correlation between FFQ and 7-DR across the intake range. Results: Repeatability for intake, explored by Pearson correlation, was 0.62–0.90 (median: 0.81. Relative validity, as determined by Pearson correlation for the nutrient intake derived from the FFQ and 7-DR, was 0.36–0.80 (0.64. The FFQ tended to report higher fiber and micronutrient intake than 7-DR. Misclassification into opposite quintiles ranged 0–6% (1%, whereas classification into same or adjacent quintiles ranged 59–83% (74%. Bland–Altman plots showed good agreement for most nutrients across the range of intake. Conclusion: This new FFQ showed a high repeatability and good relative validity, and thanks to its short length, should be a useful tool for rapidly evaluating the nutrient intake of French adults.

  9. TGC repeat expansion in the TCF4 gene increases the risk of Fuchs' endothelial corneal dystrophy in Australian cases.

    Directory of Open Access Journals (Sweden)

    Abraham Kuot

    Full Text Available Fuchs' endothelial corneal dystrophy (FECD is a progressive, vision impairing disease. Common single nucleotide polymorphisms (SNPs and a trinucleotide repeat polymorphism, thymine-guanine-cytosine (TGC, in the TCF4 gene have been associated with the risk of FECD in some populations. We previously reported association of SNPs in TCF4 with FECD risk in the Australian population. The aim of this study was to determine whether TGC repeat polymorphism in TCF4 is associated with FECD in the Australian population. In 189 unrelated Australian cases with advanced late-onset FECD and 183 matched controls, the TGC repeat polymorphism located in intron 3 of TCF4 was genotyped using a short tandem repeat (STR assay. The repeat length was verified by direct sequencing in selected homozygous carriers. We found significant association between the expanded TGC repeat (≥ 40 repeats in TCF4 and advanced FECD (P = 2.58 × 10-22; OR = 15.66 (95% CI: 7.79-31.49. Genotypic analysis showed that 51% of cases (97 compared to 5% of controls (9 were heterozygous or homozygous for the expanded repeat allele. Furthermore, the repeat expansion showed stronger association than the most significantly associated SNP, rs613872, in TCF4, with the disease in the Australian cohort. This and haplotype analysis of both the polymorphisms suggest that considering both the polymorphisms together rather than either of the two alone would better predict susceptibility to FECD in the Australian population. This is the first study to report association of the TGC trinucleotide repeat expansion in TCF4 with advanced FECD in the Australian population.

  10. Factors associated with repeated outbreak of anthrax in Bangladesh: qualitative and quantitative study

    Directory of Open Access Journals (Sweden)

    Jayedul Hassan

    2015-06-01

    Full Text Available Anthrax, caused by Bacillus anthracis is an acute, febrile disease of warm blooded animals including humans. Social norms and poverty in addition to climatic factors such as soil conditions, seasons of year, ambient temperature and rainfall influence the persistence of the B. anthracis and anthrax outbreaks. The present study was designed to reveal the factors influencing the repeated outbreak of anthrax in Bangladesh. Considering the previous outbreaks of anthrax, Sirajganj, Bogra, Kushtia, Tangail and Mymensingh districts of Bangladesh were selected for this study. To elucidate the factors, qualitative data relating to the animal management, knowledge and behavior of the people; and quantitative data relating to soil conditions, ambient temperature and rainfall were acquired, and analyzed critically. Based on the outbreak histories, a year was divided into two seasons, anthrax prone season (May-November and anthrax dry season (December-April. Anthrax spores could be isolated from 11.67% (n=14/120 of the soil samples collected from the study areas. The present study revealed that poor knowledge, lack of awareness, improper carcass disposal, inadequate vaccination, high Ca content and moisture in the soil along with high ambient temperature and rainfall during the anthrax prone season were the possible influencing factors of repeated outbreaks of anthrax in the study areas. Intensive propaganda to create public awareness of anthrax together with proper vaccination may reduce anthrax outbreaks in Bangladesh.

  11. The morphology of Ganoderma lucidum mycelium in a repeated-batch fermentation for exopolysaccharide production

    Directory of Open Access Journals (Sweden)

    Wan Abd Al Qadr Imad Wan-Mohtar

    2016-09-01

    Full Text Available The morphology of Ganoderma lucidum BCCM 31549 mycelium in a repeated-batch fermentation (RBF was studied for exopolysaccharide (EPS production. RBF was optimised for time to replace and volume to replace. G. lucidum mycelium showed the ability to self-immobilise and exhibited high stability for repeated use in RBF with engulfed pellets. Furthermore, the ovoid and starburst-like pellet morphology was disposed to EPS production in the shake flask and bioreactor, respectively. Seven RBF could be carried out in 500 mL flasks, and five repeated batches were performed in a 2 L bioreactor. Under RBF conditions, autolysis of pellet core in the shake flask and shaving off of the outer hairy region in the bioreactor were observed at the later stages of RBF (R4 for the shake flask and R6 for the bioreactor. The proposed strategy showed that the morphology of G. lucidum mycelium can withstand extended fermentation cycles.

  12. PSSRdb: a relational database of polymorphic simple sequence repeats extracted from prokaryotic genomes.

    Science.gov (United States)

    Kumar, Pankaj; Chaitanya, Pasumarthy S; Nagarajaram, Hampapathalu A

    2011-01-01

    PSSRdb (Polymorphic Simple Sequence Repeats database) (http://www.cdfd.org.in/PSSRdb/) is a relational database of polymorphic simple sequence repeats (PSSRs) extracted from 85 different species of prokaryotes. Simple sequence repeats (SSRs) are the tandem repeats of nucleotide motifs of the sizes 1-6 bp and are highly polymorphic. SSR mutations in and around coding regions affect transcription and translation of genes. Such changes underpin phase variations and antigenic variations seen in some bacteria. Although SSR-mediated phase variation and antigenic variations have been well-studied in some bacteria there seems a lot of other species of prokaryotes yet to be investigated for SSR mediated adaptive and other evolutionary advantages. As a part of our on-going studies on SSR polymorphism in prokaryotes we compared the genome sequences of various strains and isolates available for 85 different species of prokaryotes and extracted a number of SSRs showing length variations and created a relational database called PSSRdb. This database gives useful information such as location of PSSRs in genomes, length variation across genomes, the regions harboring PSSRs, etc. The information provided in this database is very useful for further research and analysis of SSRs in prokaryotes.

  13. StaRProtein, A Web Server for Prediction of the Stability of Repeat Proteins

    Science.gov (United States)

    Xu, Yongtao; Zhou, Xu; Huang, Meilan

    2015-01-01

    Repeat proteins have become increasingly important due to their capability to bind to almost any proteins and the potential as alternative therapy to monoclonal antibodies. In the past decade repeat proteins have been designed to mediate specific protein-protein interactions. The tetratricopeptide and ankyrin repeat proteins are two classes of helical repeat proteins that form different binding pockets to accommodate various partners. It is important to understand the factors that define folding and stability of repeat proteins in order to prioritize the most stable designed repeat proteins to further explore their potential binding affinities. Here we developed distance-dependant statistical potentials using two classes of alpha-helical repeat proteins, tetratricopeptide and ankyrin repeat proteins respectively, and evaluated their efficiency in predicting the stability of repeat proteins. We demonstrated that the repeat-specific statistical potentials based on these two classes of repeat proteins showed paramount accuracy compared with non-specific statistical potentials in: 1) discriminate correct vs. incorrect models 2) rank the stability of designed repeat proteins. In particular, the statistical scores correlate closely with the equilibrium unfolding free energies of repeat proteins and therefore would serve as a novel tool in quickly prioritizing the designed repeat proteins with high stability. StaRProtein web server was developed for predicting the stability of repeat proteins. PMID:25807112

  14. The diversity and evolution of Wolbachia ankyrin repeat domain genes.

    Directory of Open Access Journals (Sweden)

    Stefanos Siozios

    Full Text Available Ankyrin repeat domain-encoding genes are common in the eukaryotic and viral domains of life, but they are rare in bacteria, the exception being a few obligate or facultative intracellular Proteobacteria species. Despite having a reduced genome, the arthropod strains of the alphaproteobacterium Wolbachia contain an unusually high number of ankyrin repeat domain-encoding genes ranging from 23 in wMel to 60 in wPip strain. This group of genes has attracted considerable attention for their astonishing large number as well as for the fact that ankyrin proteins are known to participate in protein-protein interactions, suggesting that they play a critical role in the molecular mechanism that determines host-Wolbachia symbiotic interactions. We present a comparative evolutionary analysis of the wMel-related ankyrin repeat domain-encoding genes present in different Drosophila-Wolbachia associations. Our results show that the ankyrin repeat domain-encoding genes change in size by expansion and contraction mediated by short directly repeated sequences. We provide examples of intra-genic recombination events and show that these genes are likely to be horizontally transferred between strains with the aid of bacteriophages. These results confirm previous findings that the Wolbachia genomes are evolutionary mosaics and illustrate the potential that these bacteria have to generate diversity in proteins potentially involved in the symbiotic interactions.

  15. Impact of repeated single-metal and multi-metal pollution events on soil quality.

    Science.gov (United States)

    Burges, Aritz; Epelde, Lur; Garbisu, Carlos

    2015-02-01

    Most frequently, soil metal pollution results from the occurrence of repeated single-metal and, above all, multi-metal pollution events, with concomitant adverse consequences for soil quality. Therefore, in this study, we evaluated the impact of repeated single-metal and multi-metal (Cd, Pb, Cu, Zn) pollution events on soil quality, as reflected by the values of a variety of soil microbial parameters with potential as bioindicators of soil functioning. Specifically, parameters of microbial activity (potentially mineralizable nitrogen, β-glucosidase and acid phosphatase activity) and biomass (fungal and bacterial gene abundance by RT-qPCR) were determined, in the artificially metal-polluted soil samples, at regular intervals over a period of 26 weeks. Similarly, we studied the evolution over time of CaCl2-extractable metal fractions, in order to estimate metal bioavailability in soil. Different metals showed different values of bioavailability and relative bioavailability ([metal]bio/[metal]tot) in soil throughout the experiment, under both repeated single-metal and multi-metal pollution events. Both repeated Zn-pollution and multi-metal pollution events led to a significant reduction in the values of acid phosphatase activity, and bacterial and fungal gene abundance, reflecting the negative impact of these repeated events on soil microbial activity and biomass, and, hence, soil quality. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. CAG repeat polymorphisms in the androgen receptor and breast cancer risk in women: a meta-analysis of 17 studies

    Directory of Open Access Journals (Sweden)

    Mao Q

    2015-08-01

    Full Text Available Qixing Mao,1–3,* Mantang Qiu,1–3,* Gaochao Dong,3 Wenjie Xia,1–3 Shuai Zhang,1,3 Youtao Xu,1,3 Jie Wang,3 Yin Rong,1,3 Lin Xu,1,3 Feng Jiang1,3 1Department of Thoracic Surgery, Nanjing Medical University Affiliated Cancer Institute of Jiangsu Province, 2Fourth Clinical College of Nanjing Medical University, 3Jiangsu Key Laboratory of Molecular and Translational Cancer Research, Nanjing, People’s Republic of China *These authors contributed equally to this work Abstract: The association between polymorphic CAG repeats in the androgen receptor gene in women and breast cancer susceptibility has been studied extensively. However, the conclusions regarding this relationship remain conflicting. The purpose of this meta-analysis was to identify whether androgen receptor CAG repeat lengths were related to breast cancer susceptibility. The MEDLINE, PubMed, and EMBASE databases were searched through to December 2014 to identify eligible studies. Data and study quality were rigorously assessed by two investigators according to the Newcastle-Ottawa Quality Assessment Scale. The publication bias was assessed by the Begg’s test. Seventeen eligible studies were included in this meta-analysis. The overall analysis suggested no association between CAG polymorphisms and breast cancer risk (odds ratio [OR] 1.031, 95% confidence interval [CI] 0.855–1.245. However, in the subgroup analysis, we observed that long CAG repeats significantly increased the risk of breast cancer in the Caucasian population (OR 1.447, 95% CI 1.089–1.992. Additionally, the risk was significantly increased in Caucasian women carrying two alleles with CAG repeats ≥22 units compared with those with two shorter alleles (OR 1.315, 95% CI 1.014–1.707. These findings suggest that long CAG repeats increase the risk of breast cancer in Caucasian women. However, larger scale case-control studies are needed to validate our results. Keywords: androgen, CAG repeat polymorphism, women

  17. Oxidative stress adaptation with acute, chronic, and repeated stress.

    Science.gov (United States)

    Pickering, Andrew M; Vojtovich, Lesya; Tower, John; A Davies, Kelvin J

    2013-02-01

    Oxidative stress adaptation, or hormesis, is an important mechanism by which cells and organisms respond to, and cope with, environmental and physiological shifts in the level of oxidative stress. Most studies of oxidative stress adaption have been limited to adaptation induced by acute stress. In contrast, many if not most environmental and physiological stresses are either repeated or chronic. In this study we find that both cultured mammalian cells and the fruit fly Drosophila melanogaster are capable of adapting to chronic or repeated stress by upregulating protective systems, such as their proteasomal proteolytic capacity to remove oxidized proteins. Repeated stress adaptation resulted in significant extension of adaptive responses. Repeated stresses must occur at sufficiently long intervals, however (12-h or more for MEF cells and 7 days or more for flies), for adaptation to be successful, and the levels of both repeated and chronic stress must be lower than is optimal for adaptation to acute stress. Regrettably, regimens of adaptation to both repeated and chronic stress that were successful for short-term survival in Drosophila nevertheless also caused significant reductions in life span for the flies. Thus, although both repeated and chronic stress can be tolerated, they may result in a shorter life. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Repeated mild traumatic brain injury can cause acute neurologic impairment without overt structural damage in juvenile rats.

    Directory of Open Access Journals (Sweden)

    Alicia Meconi

    Full Text Available Repeated concussion is becoming increasingly recognized as a serious public health concern around the world. Moreover, there is a greater awareness amongst health professionals of the potential for repeated pediatric concussions to detrimentally alter the structure and function of the developing brain. To better study this issue, we developed an awake closed head injury (ACHI model that enabled repeated concussions to be performed reliably and reproducibly in juvenile rats. A neurological assessment protocol (NAP score was generated immediately after each ACHI to help quantify the cumulative effects of repeated injury on level of consciousness, and basic motor and reflexive capacity. Here we show that we can produce a repeated ACHI (4 impacts in two days in both male and female juvenile rats without significant mortality or pain. We show that both single and repeated injuries produce acute neurological deficits resembling clinical concussion symptoms that can be quantified using the NAP score. Behavioural analyses indicate repeated ACHI acutely impaired spatial memory in the Barnes maze, and an interesting sex effect was revealed as memory impairment correlated moderately with poorer NAP score performance in a subset of females. These cognitive impairments occurred in the absence of motor impairments on the Rotarod, or emotional changes in the open field and elevated plus mazes. Cresyl violet histology and structural magnetic resonance imaging (MRI indicated that repeated ACHI did not produce significant structural damage. MRI also confirmed there was no volumetric loss in the cortex, hippocampus, or corpus callosum of animals at 1 or 7 days post-ACHI. Together these data indicate that the ACHI model can provide a reliable, high throughput means to study the effects of concussions in juvenile rats.

  19. Reasons for and functional results of repeated hip arthroscopy: A continuous prospective study of 17 revisions out of 295 primary hip arthroscopies at mean 28months' follow-up.

    Science.gov (United States)

    Tissot, C; Merlini, L; Mercier, M; Bonin, N

    2017-09-01

    The rate of iterative arthroscopy has been increasing over the last decade as the technique has grown. The results of and reasons for these revision procedures, however, are not exactly known. We therefore conducted a prospective study to shed light on: 1) functional results and patient satisfaction following repeated arthroscopy, and 2) the relevant indications. Functional scores and patient satisfaction increase following repeated arthroscopy. MATERIALS AND METHOD: A single-center continuous prospective study without control group included patients undergoing repeated hip arthroscopy between September 2010 and September 2014, with a mean 28months' follow-up (median, 23.3months; range, 12-62months). Preoperative and follow-up functional assessment used the modified Harris hip, WOMAC and Christensen (NHAS) questionnaires, and a satisfaction scale. On etiological analysis, repeated arthroscopy was indicated if a cause of recurrent or persistent pain accessible to arthroscopic treatment was identified. Seventeen patients were included out of 295 primary arthroscopies (5.7%): 9 male, 8 female; median age, 29.6years (range, 16-48years). Indications for primary arthroscopy comprised 13 cases of femoroacetabular impingement, 3 labrum lesions with instability, 1 chondromatosis and 1 case of osteoarthritis. Eleven of the 17 primary lesions showed persistence, including 9 of the 13 cases of femoroacetabular impingement. There were 3 failures in 17 repeated arthroscopies. All functional scores improved, with a gain of 7 points (P<0.06) on modified Harris hip score, 25 points (P<0.0006) on WOMAC score, and 27 points (P<0.001) on NHAS score. Ten of the 17 patients were satisfied or very satisfied with the repeated arthroscopy (59%). Although less good than on primary arthroscopy, functional results on repeated hip arthroscopy were satisfactory in the short term. The main reason for repeated arthroscopy was persistence of initial abnormality due to insufficient treatment

  20. simple sequence repeat (SSR)

    African Journals Online (AJOL)

    In the present study, 78 mapped simple sequence repeat (SSR) markers representing 11 linkage groups of adzuki bean were evaluated for transferability to mungbean and related Vigna spp. 41 markers amplified characteristic bands in at least one Vigna species. The transferability percentage across the genotypes ranged ...

  1. Evaluation of the repeated-dose liver micronucleus assay using N-nitrosomorpholine in young adult rats: report on collaborative study by the Collaborative Study Group for the Micronucleus Test (CSGMT)/Japanese Environmental Mutagen Society (JEMS)-Mammalian Mutagenicity Study (MMS) Group.

    Science.gov (United States)

    Hayashi, Aya; Kosaka, Mizuki; Kimura, Aoi; Wako, Yumi; Kawasako, Kazufumi; Hamada, Shuichi

    2015-03-01

    The present study was conducted to evaluate the suitability of a repeated-dose liver micronucleus (LMN) assay in young adult rats as a collaborative study by the Mammalian mutagenicity study (MMS) group. All procedures were performed in accordance with the standard protocols of the MMS Group. Six-week-old male Crl:CD(SD) rats (5 animals/group) received oral doses of the hepatocarcinogen N-nitrosomorpholine (NMOR) at 0 (control), 5, 10, and 30mg/kg/day (10mL/kg) for 14 days. Control animals received vehicle (water). Hepatocytes were collected from the liver 24h after the last dose, and the number of micronucleated hepatocytes (MNHEPs) was determined by microscopy. The number of micronucleated immature erythrocytes (MNIMEs) in the femoral bone marrow was also determined. The liver was examined using histopathologic methods after formalin fixation. The results showed statistically significant and dose-dependent increases in the number of MNHEPs in the liver at doses of 10mg/kg and greater when compared with the vehicle control. However, no significant increase was noted in the number of MNIMEs in the bone marrow at doses of up to 30mg/kg. Histopathology of the liver revealed hypertrophy and single cell necrosis of hepatocytes at doses of 5mg/kg and above. These results showed that the induction of micronuclei by NMOR was detected by the repeated-dose LMN assay, but not by the repeated-dose bone marrow micronucleus assay. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Ten days of repeated local forearm heating does not affect cutaneous vascular function.

    Science.gov (United States)

    Francisco, Michael A; Brunt, Vienna E; Jensen, Krista Nicole; Lorenzo, Santiago; Minson, Christopher T

    2017-08-01

    The aim of the present study was to determine whether 10 days of repeated local heating could induce peripheral adaptations in the cutaneous vasculature and to investigate potential mechanisms of adaptation. We also assessed maximal forearm blood flow to determine whether repeated local heating affects maximal dilator capacity. Before and after 10 days of heat training consisting of 1-h exposures of the forearm to 42°C water or 32°C water (control) in the contralateral arm (randomized and counterbalanced), we assessed hyperemia to rapid local heating of the skin ( n = 14 recreationally active young subjects). In addition, sequential doses of acetylcholine (ACh, 1 and 10 mM) were infused in a subset of subjects ( n = 7) via microdialysis to study potential nonthermal microvascular adaptations following 10 days of repeated forearm heat training. Skin blood flow was assessed using laser-Doppler flowmetry, and cutaneous vascular conductance (CVC) was calculated as laser-Doppler red blood cell flux divided by mean arterial pressure. Maximal cutaneous vasodilation was achieved by heating the arm in a water-spray device for 45 min and assessed using venous occlusion plethysmography. Forearm vascular conductance (FVC) was calculated as forearm blood flow divided by mean arterial pressure. Repeated forearm heating did not increase plateau percent maximal CVC (CVC max ) responses to local heating (89 ± 3 vs. 89 ± 2% CVC max , P = 0.19), 1 mM ACh (43 ± 9 vs. 53 ± 7% CVC max , P = 0.76), or 10 mM ACh (61 ± 9 vs. 85 ± 7% CVC max , P = 0.37, by 2-way repeated-measures ANOVA). There was a main effect of time at 10 mM ACh ( P = 0.03). Maximal FVC remained unchanged (0.12 ± 0.02 vs. 0.14 ± 0.02 FVC, P = 0.30). No differences were observed in the control arm. Ten days of repeated forearm heating in recreationally active young adults did not improve the microvascular responsiveness to ACh or local heating. NEW & NOTEWORTHY We show for the first time that 10 days of repeated

  3. Performance Comparisons of Improved Regular Repeat Accumulate (RA and Irregular Repeat Accumulate (IRA Turbo Decoding

    Directory of Open Access Journals (Sweden)

    Ahmed Abdulkadhim Hamad

    2017-08-01

    Full Text Available In this paper, different techniques are used to improve the turbo decoding of regular repeat accumulate (RA and irregular repeat accumulate (IRA codes. The adaptive scaling of a-posteriori information produced by Soft-output Viterbi decoder (SOVA is proposed. The encoded pilots are another scheme that applied for short length RA codes. This work also suggests a simple and a fast method to generate a random interleaver having a free 4 cycle Tanner graph. Progressive edge growth algorithm (PEG is also studied and simulated to create the Tanner graphs which have a great girth.

  4. 78 FR 65594 - Vehicular Repeaters

    Science.gov (United States)

    2013-11-01

    ... coordinators estimate the effect on coordination fees? Does the supposed benefit that mobile repeater stations... allow the licensing and operation of vehicular repeater systems and other mobile repeaters by public... email: [email protected] or phone: 202-418- 0530 or TTY: 202-418-0432. For detailed instructions for...

  5. Whole blood DNA aberrant methylation in pancreatic adenocarcinoma shows association with the course of the disease: a pilot study.

    Directory of Open Access Journals (Sweden)

    Albertas Dauksa

    Full Text Available Pancreatic tumors are usually diagnosed at an advanced stage in the progression of the disease, thus reducing the survival chances of the patients. Non-invasive early detection would greatly enhance therapy and survival rates. Toward this aim, we investigated in a pilot study the power of methylation changes in whole blood as predictive markers for the detection of pancreatic tumors. We investigated methylation levels at selected CpG sites in the CpG rich regions at the promoter regions of p16, RARbeta, TNFRSF10C, APC, ACIN1, DAPK1, 3OST2, BCL2 and CD44 in the blood of 30 pancreatic tumor patients and in the blood of 49 matching controls. In addition, we studied LINE-1 and Alu repeats using degenerate amplification approach as a surrogate marker for genome-wide methylation. The site-specific methylation measurements at selected CpG sites were done by the SIRPH method. Our results show that in the patient's blood, tumor suppressor genes were slightly but significantly higher methylated at several CpG sites, while repeats were slightly less methylated compared to control blood. This was found to be significantly associated with higher risk for pancreatic ductal adenocarcinoma. Additionally, high methylation levels at TNFRSCF10C were associated with positive perineural spread of tumor cells, while higher methylation levels of TNFRSF10C and ACIN1 were significantly associated with shorter survival. This pilot study shows that methylation changes in blood could provide a promising method for early detection of pancreatic tumors. However, larger studies must be carried out to explore the clinical usefulness of a whole blood methylation based test for non-invasive early detection of pancreatic tumors.

  6. Tevatron serial data repeater system

    International Nuclear Information System (INIS)

    Ducar, R.J.

    1981-01-01

    A ten megabit per second serial data repeater system has been developed for the 6.28km Tevatron accelerator. The repeaters are positioned at each of the thirty service buildings and accommodate control and abort system communications as well as distribution of the Tevatron time and energy clocks. The repeaters are transparent to the particular protocol of the transmissions. Serial data are encoded locally as unipolar two volt signals employing the self-clocking Manchester Bi-Phase code. The repeaters modulate the local signals to low-power bursts of 50 MHz rf carrier for the 260m transmission between service buildings. The repeaters also demodulate the transmission and restructure the data for local utilization. The employment of frequency discrimination techniques yields high immunity to the characteristic noise spectrum

  7. Repeated causal decision making.

    Science.gov (United States)

    Hagmayer, York; Meder, Björn

    2013-01-01

    Many of our decisions refer to actions that have a causal impact on the external environment. Such actions may not only allow for the mere learning of expected values or utilities but also for acquiring knowledge about the causal structure of our world. We used a repeated decision-making paradigm to examine what kind of knowledge people acquire in such situations and how they use their knowledge to adapt to changes in the decision context. Our studies show that decision makers' behavior is strongly contingent on their causal beliefs and that people exploit their causal knowledge to assess the consequences of changes in the decision problem. A high consistency between hypotheses about causal structure, causally expected values, and actual choices was observed. The experiments show that (a) existing causal hypotheses guide the interpretation of decision feedback, (b) consequences of decisions are used to revise existing causal beliefs, and (c) decision makers use the experienced feedback to induce a causal model of the choice situation even when they have no initial causal hypotheses, which (d) enables them to adapt their choices to changes of the decision problem. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  8. Hearing loss associated with repeated MRI acquisition procedure-related acoustic noise exposure: an occupational cohort study

    NARCIS (Netherlands)

    Bongers, Suzan; Slottje, Pauline; Kromhout, Hans

    2017-01-01

    OBJECTIVE: To study the effects of repeated exposure to MRI-related acoustic noise during image acquisition procedures (scans) on hearing. METHODS: A retrospective occupational cohort study was performed among workers of an MRI manufacturing facility (n=474). Longitudinal audiometry data from the

  9. The role of temporal delay and repeated prospective memory cue exposure on the deactivation of completed intentions.

    Science.gov (United States)

    Walser, Moritz; Plessow, Franziska; Goschke, Thomas; Fischer, Rico

    2014-07-01

    Previous studies have shown that completed prospective memory (PM) intentions entail aftereffects in terms of ongoing-task-performance decrements in trials containing repeated PM cues which previously served as PM cues triggering the intended action. Previous research reported that PM aftereffects decrease over time, thus revealing a specific time course of PM aftereffects. In the present study, we tested two accounts for this pattern, assuming either that the decline of aftereffects is related to the temporal distance to PM task completion or may be a result of the repeated exposure of repeated PM cues in the ongoing task. In three experiments, we manipulated both the temporal distance to PM task completion and the frequency of repeated PM cues and demonstrated that aftereffects of completed intentions declined with repeated exposure of formerly relevant PM cues. In addition, effects of repeated exposure were not only limited to the repetition of specific PM-cue exemplars but also generalized to other semantically related PM cues within the PM-cue category. Together, findings show that decreased aftereffects of completed intentions are not related to the temporal duration of the subsequent test block, but crucially depend on the repeated exposure of the previously relevant PM cues.

  10. Repeat Customer Success in Extension

    Science.gov (United States)

    Bess, Melissa M.; Traub, Sarah M.

    2013-01-01

    Four multi-session research-based programs were offered by two Extension specialist in one rural Missouri county. Eleven participants who came to multiple Extension programs could be called "repeat customers." Based on the total number of participants for all four programs, 25% could be deemed as repeat customers. Repeat customers had…

  11. Repeat migration and disappointment.

    Science.gov (United States)

    Grant, E K; Vanderkamp, J

    1986-01-01

    This article investigates the determinants of repeat migration among the 44 regions of Canada, using information from a large micro-database which spans the period 1968 to 1971. The explanation of repeat migration probabilities is a difficult task, and this attempt is only partly successful. May of the explanatory variables are not significant, and the overall explanatory power of the equations is not high. In the area of personal characteristics, the variables related to age, sex, and marital status are generally significant and with expected signs. The distance variable has a strongly positive effect on onward move probabilities. Variables related to prior migration experience have an important impact that differs between return and onward probabilities. In particular, the occurrence of prior moves has a striking effect on the probability of onward migration. The variable representing disappointment, or relative success of the initial move, plays a significant role in explaining repeat migration probabilities. The disappointment variable represents the ratio of actural versus expected wage income in the year after the initial move, and its effect on both repeat migration probabilities is always negative and almost always highly significant. The repeat probabilities diminish after a year's stay in the destination region, but disappointment in the most recent year still has a bearing on the delayed repeat probabilities. While the quantitative impact of the disappointment variable is not large, it is difficult to draw comparisons since similar estimates are not available elsewhere.

  12. Inter- and intra-operator reliability and repeatability of shear wave elastography in the liver: a study in healthy volunteers.

    Science.gov (United States)

    Hudson, John M; Milot, Laurent; Parry, Craig; Williams, Ross; Burns, Peter N

    2013-06-01

    This study assessed the reproducibility of shear wave elastography (SWE) in the liver of healthy volunteers. Intra- and inter-operator reliability and repeatability were quantified in three different liver segments in a sample of 15 subjects, scanned during four independent sessions (two scans on day 1, two scans 1 wk later) by two operators. A total of 1440 measurements were made. Reproducibility was assessed using the intra-class correlation coefficient (ICC) and a repeated measures analysis of variance. The shear wave speed was measured and used to estimate Young's modulus using the Supersonics Imagine Aixplorer. The median Young's modulus measured through the inter-costal space was 5.55 ± 0.74 kPa. The intra-operator reliability was better for same-day evaluations (ICC = 0.91) than the inter-operator reliability (ICC = 0.78). Intra-observer agreement decreased when scans were repeated on a different day. Inter-session repeatability was between 3.3% and 9.9% for intra-day repeated scans, compared with to 6.5%-12% for inter-day repeated scans. No significant difference was observed in subjects with a body mass index greater or less than 25 kg/m(2). Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  13. Reproducibility and Reliability of Repeated Quantitative Fluorescence Angiography

    DEFF Research Database (Denmark)

    Nerup, Nikolaj; Knudsen, Kristine Bach Korsholm; Ambrus, Rikard

    2017-01-01

    INTRODUCTION: When using fluorescence angiography (FA) in perioperative perfusion assessment, repeated measures with re-injections of fluorescent dye (ICG) may be required. However, repeated injections may cause saturation of dye in the tissue, exceeding the limit of fluorescence intensity...... that the camera can detect. As the emission of fluorescence is dependent of the excitatory light intensity, reduction of this may solve the problem. The aim of the present study was to investigate the reproducibility and reliability of repeated quantitative FA during a reduction of excitatory light....

  14. The absolute number of repeat operations for complex intra ...

    African Journals Online (AJOL)

    abdominal sepsis, questions about futility of treatment frequently arise. This study focuses specifically on patients who required two or more repeat laparotomies and describes the spectrum of disease necessitating multiple repeat laparotomies ...

  15. Repeated mild closed head injury impairs short-term visuospatial memory and complex learning.

    Science.gov (United States)

    Hylin, Michael J; Orsi, Sara A; Rozas, Natalia S; Hill, Julia L; Zhao, Jing; Redell, John B; Moore, Anthony N; Dash, Pramod K

    2013-05-01

    Concussive force can cause neurocognitive and neurobehavioral dysfunction by inducing functional, electrophysiological, and/or ultrastructural changes within the brain. Although concussion-triggered symptoms typically subside within days to weeks in most people, in 15%-20% of the cases, symptomology can continue beyond this time point. Problems with memory, attention, processing speed, and cognitive flexibility (e.g., problem solving, conflict resolution) are some of the prominent post-concussive cognitive symptoms. Repeated concussions (with loss or altered consciousness), which are common to many contact sports, can exacerbate these symptoms. The pathophysiology of repeated concussions is not well understood, nor is an effective treatment available. In order to facilitate drug discovery to treat post-concussive symptoms (PCSs), there is a need to determine if animal models of repeated mild closed head injury (mCHI) can mimic the neurocognitive and histopathological consequences of repeated concussions. To this end, we employed a controlled cortical impact (CCI) device to deliver a mCHI directly to the skull of mice daily for 4 days, and examined the ensuing neurological and neurocognitive functions using beam balance, foot-fault, an abbreviated Morris water maze test, context discrimination, and active place avoidance tasks. Repeated mCHI exacerbated vestibulomotor, motor, short-term memory and conflict learning impairments as compared to a single mCHI. Learning and memory impairments were still observed in repeated mCHI mice when tested 3 months post-injury. Repeated mCHI also reduced cerebral perfusion, prolonged the inflammatory response, and in some animals, caused hippocampal neuronal loss. Our results show that repeated mCHI can reproduce some of the deficits seen after repeated concussions in humans and may be suitable for drug discovery studies and translational research.

  16. Layered Architectures for Quantum Computers and Quantum Repeaters

    Science.gov (United States)

    Jones, Nathan C.

    This chapter examines how to organize quantum computers and repeaters using a systematic framework known as layered architecture, where machine control is organized in layers associated with specialized tasks. The framework is flexible and could be used for analysis and comparison of quantum information systems. To demonstrate the design principles in practice, we develop architectures for quantum computers and quantum repeaters based on optically controlled quantum dots, showing how a myriad of technologies must operate synchronously to achieve fault-tolerance. Optical control makes information processing in this system very fast, scalable to large problem sizes, and extendable to quantum communication.

  17. Repeatability and reproducibility of decisions by latent fingerprint examiners.

    Directory of Open Access Journals (Sweden)

    Bradford T Ulery

    Full Text Available The interpretation of forensic fingerprint evidence relies on the expertise of latent print examiners. We tested latent print examiners on the extent to which they reached consistent decisions. This study assessed intra-examiner repeatability by retesting 72 examiners on comparisons of latent and exemplar fingerprints, after an interval of approximately seven months; each examiner was reassigned 25 image pairs for comparison, out of total pool of 744 image pairs. We compare these repeatability results with reproducibility (inter-examiner results derived from our previous study. Examiners repeated 89.1% of their individualization decisions, and 90.1% of their exclusion decisions; most of the changed decisions resulted in inconclusive decisions. Repeatability of comparison decisions (individualization, exclusion, inconclusive was 90.0% for mated pairs, and 85.9% for nonmated pairs. Repeatability and reproducibility were notably lower for comparisons assessed by the examiners as "difficult" than for "easy" or "moderate" comparisons, indicating that examiners' assessments of difficulty may be useful for quality assurance. No false positive errors were repeated (n = 4; 30% of false negative errors were repeated. One percent of latent value decisions were completely reversed (no value even for exclusion vs. of value for individualization. Most of the inter- and intra-examiner variability concerned whether the examiners considered the information available to be sufficient to reach a conclusion; this variability was concentrated on specific image pairs such that repeatability and reproducibility were very high on some comparisons and very low on others. Much of the variability appears to be due to making categorical decisions in borderline cases.

  18. Single molecule study of the intrinsically disordered FG-repeat nucleoporin 153.

    Science.gov (United States)

    Milles, Sigrid; Lemke, Edward A

    2011-10-05

    Nucleoporins (Nups), which are intrinsically disordered, form a selectivity filter inside the nuclear pore complex, taking a central role in the vital nucleocytoplasmic transport mechanism. These Nups display a complex and nonrandom amino-acid architecture of phenylalanine glycine (FG)-repeat clusters and intra-FG linkers. How such heterogeneous sequence composition relates to function and could give rise to a transport mechanism is still unclear. Here we describe a combined chemical biology and single-molecule fluorescence approach to study the large human Nup153 FG-domain. In order to obtain insights into the properties of this domain beyond the average behavior, we probed the end-to-end distance (R(E)) of several ∼50-residues long FG-repeat clusters in the context of the whole protein domain. Despite the sequence heterogeneity of these FG-clusters, we detected a reoccurring and consistent compaction from a relaxed coil behavior under denaturing conditions (R(E)/R(E,RC) = 0.99 ± 0.15 with R(E,RC) corresponding to ideal relaxed coil behavior) to a collapsed state under native conditions (R(E)/R(E,RC) = 0.79 ± 0.09). We then analyzed the properties of this protein on the supramolecular level, and determined that this human FG-domain was in fact able to form a hydrogel with physiological permeability barrier properties. Copyright © 2011 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  19. Thermal, cardiac and adrenergic responses to repeated local cooling.

    Science.gov (United States)

    Janský, L; Matousková, E; Vávra, V; Vybíral, S; Janský, P; Jandová, D; Knízková, I; Kunc, P

    2006-01-01

    The aim of this study was to ascertain whether repeated local cooling induces the same or different adaptational responses as repeated whole body cooling. Repeated cooling of the legs (immersion into 12 degrees C water up to the knees for 30 min, 20 times during 4 weeks = local cold adaptation - LCA) attenuated the initial increase in heart rate and blood pressure currently observed in control subjects immersed in cold water up to the knees. After LCA the initial skin temperature decrease tended to be lower, indicating reduced vasoconstriction. Heart rate and systolic blood pressure appeared to be generally lower during rest and during the time course of cooling in LCA humans, when compared to controls. All these changes seem to indicate attenuation of the sympathetic tone. In contrast, the sustained skin temperature in different areas of the body (finger, palm, forearm, thigh, chest) appeared to be generally lower in LCA subjects than in controls (except for temperatures on the forehead). Plasma levels of catecholamines (measured 20 and 40 min after the onset of cooling) were also not influenced by local cold adaptation. Locally cold adapted subjects, when exposed to whole body cold water immersion test, showed no change in the threshold temperature for induction of cold thermogenesis. This indicates that the hypothermic type of cold adaptation, typically occurring after systemic cold adaptation, does not appear after local cold adaptation of the intensity used. It is concluded that in humans the cold adaptation due to repeated local cooling of legs induces different physiological changes than systemic cold adaptation.

  20. Ocular surface sensitivity repeatability with Cochet-Bonnet esthesiometer.

    Science.gov (United States)

    Chao, Cecilia; Stapleton, Fiona; Badarudin, Ezailina; Golebiowski, Blanka

    2015-02-01

    To determine the repeatability of ocular surface threshold measurements using the Cochet-Bonnet esthesiometer on the same day and 3 months apart. Two separate studies were conducted to determine the repeatability of ocular surface threshold measurements made on the same day (n = 20 subjects) and 3 months apart (n = 29 subjects). The Cochet-Bonnet esthesiometer was used to measure corneal and inferior conjunctival thresholds using the ascending method of limits. The pressure exerted by the Cochet-Bonnet esthesiometer was determined using an analytical balance, for both the 0.08- and 0.12-mm-diameter filaments. This calibration was then used to convert filament length measurements to pressure. Repeatability was determined using a Bland and Altman analysis. The pressure exerted at each filament length differed between the two filament diameters. The measured pressure also differed from values provided by the manufacturer. Repeatability of threshold measurements at the central cornea was shown to be good, with better repeatability for same-day measurements (coefficient of repeatability [CoR] = ±0.23 g/mm²) than for those 3 months apart (CoR = ±0.52 g/mm²). Threshold measurements at the inferior conjunctiva, in contrast, were poorly repeatable (CoR = ±12.78 g/mm²). Cochet-Bonnet esthesiometry is repeatable when performed on the central cornea on the same day and 3 months apart, but this instrument is not recommended for conjunctival threshold measurements.

  1. Prevalence and Determinants of Repeat Mammography Among Women from a Developing Country.

    Science.gov (United States)

    Salinas-Martínez, Ana María; Gaspar-Rivera, Jimena Estefanía; Juárez-Pérez, Oscar; Montañez-Sauceda, José Roberto; Núñez-Rocha, Georgina Mayela; Guzmán-de-la-Garza, Francisco Javier; Mathiew-Quirós, Álvaro

    2017-04-01

    Failures in repeat mammography decrease the potential benefits of screening; however, it is notable that the recent use of mammography is more frequently studied than repeat use. We estimated the prevalence and analyzed determinants for repeat mammography among women from Mexico, a developing country of Latin America. It was a two-stage study with an initial cross-sectional design (n = 1045) and a final case-control design that involved women of at least 45 years of age with no history of breast, ovarian, or uterine cancer. Case subjects were those with three or more mammograms in the last 5 years, with the last one carried out within the last two years (n = 444); control subjects included those who underwent ≥3 mammograms throughout their life with the most recent carried out >2 years ago (n = 444). Through interviews, we evaluated context-dependency, fulfillment of expected outcomes, self-efficacy, and risk perception, among other factors. We estimated the prevalence with 95 % confidence intervals (CI), and odds ratios (OR) using multivariate binary logistic regression. The prevalence of repeat mammography was 40.4 % (95 % CI 37.4-43.4). Self-efficacy demonstrated the highest effect on repeat use (OR 7.7, 95 % CI 4.7-12.6), followed by awareness context-dependency (OR 4.9, 95 % CI 3.3-7.2), the use of Papanicolaou testing (OR 3.5, 95 % CI 2.3-5.2), the fulfillment of expected waiting time outcome (OR 2.4, 95 % CI 1.2-4.7), and context-dependency related to self-referral/health provider referral (OR 2.4, 95 % CI 1.7-3.4), independent of risk perception, age, education, and positive emotional state of mind. The study showed a need for increasing the prevalence of promoting awareness of the determining factors of repeat mammography, which is a necessary component in the early detection of breast cancer.

  2. TU-AB-BRA-05: Repeatability of [F-18]-NaF PET Imaging Biomarkers for Bone Lesions: A Multicenter Study

    International Nuclear Information System (INIS)

    Lin, C; Bradshaw, T; Perk, T; Harmon, S; Jeraj, R; Liu, G

    2015-01-01

    Purpose: Quantifying the repeatability of imaging biomarkers is critical for assessing therapeutic response. While therapeutic efficacy has been traditionally quantified by SUV metrics, imaging texture features have shown potential for use as quantitative biomarkers. In this study we evaluated the repeatability of quantitative "1"8F-NaF PET-derived SUV metrics and texture features in bone lesions from patients in a multicenter study. Methods: Twenty-nine metastatic castrate-resistant prostate cancer patients received whole-body test-retest NaF PET/CT scans from one of three harmonized imaging centers. Bone lesions of volume greater than 1.5 cm"3 were identified and automatically segmented using a SUV>15 threshold. From each lesion, 55 NaF PET-derived texture features (including first-order, co-occurrence, grey-level run-length, neighbor gray-level, and neighbor gray-tone difference matrix) were extracted. The test-retest repeatability of each SUV metric and texture feature was assessed with Bland-Altman analysis. Results: A total of 315 bone lesions were evaluated. Of the traditional SUV metrics, the repeatability coefficient (RC) was 12.6 SUV for SUVmax, 2.5 SUV for SUVmean, and 4.3 cm"3 for volume. Their respective intralesion coefficients of variation (COVs) were 12%, 17%, and 6%. Of the texture features, COV was lowest for entropy (0.03%) and highest for kurtosis (105%). Lesion intraclass correlation coefficient (ICC) was lowest for maximum correlation coefficient (ICC=0.848), and highest for entropy (ICC=0.985). Across imaging centers, repeatability of texture features and SUV varied. For example, across imaging centers, COV for SUVmax ranged between 11–23%. Conclusion: Many NaF PET-derived SUV metrics and texture features for bone lesions demonstrated high repeatability, such as SUVmax, entropy, and volume. Several imaging texture features demonstrated poor repeatability, such as SUVtotal and SUVstd. These results can be used to establish response criteria

  3. Repfinder: Finding approximately repeated scene elements for image editing

    KAUST Repository

    Cheng, Ming-Ming

    2010-07-26

    Repeated elements are ubiquitous and abundant in both manmade and natural scenes. Editing such images while preserving the repetitions and their relations is nontrivial due to overlap, missing parts, deformation across instances, illumination variation, etc. Manually enforcing such relations is laborious and error-prone. We propose a novel framework where user scribbles are used to guide detection and extraction of such repeated elements. Our detection process, which is based on a novel boundary band method, robustly extracts the repetitions along with their deformations. The algorithm only considers the shape of the elements, and ignores similarity based on color, texture, etc. We then use topological sorting to establish a partial depth ordering of overlapping repeated instances. Missing parts on occluded instances are completed using information from other instances. The extracted repeated instances can then be seamlessly edited and manipulated for a variety of high level tasks that are otherwise difficult to perform. We demonstrate the versatility of our framework on a large set of inputs of varying complexity, showing applications to image rearrangement, edit transfer, deformation propagation, and instance replacement. © 2010 ACM.

  4. The need for repeat angiography in subarachnoid haemorrhage

    International Nuclear Information System (INIS)

    Urbach, H.; Solymosi, L.; Zentner, J.

    1998-01-01

    This study was designed to assess the necessity for a second angiogram study in patients in whom initial angiography after primary subarachnoid haemorrhage (SAH) was negative. During a 12-year period, 122 of 694 patients (17.5 %) had negative initial angiograms. CT, available for 98 patients, showed a preponderance of subarachnoid blood in the perimesencephalic cisterns in 50 of 73 patients (68.5 %) in whom blood was visible on CT. Angiography, repeated in 67 patients, revealed an aneurysm in 4 (6 %): 2 had an aneurysm of the anterior communicating artery, 1 of the posterior inferior cerebellar artery, and 1 of the P2 segment of the posterior cerebral artery. CT showed subarachnoid blood in the interpeduncular and ambient cisterns in this last case, and a preponderance of subarachnoid blood outside the perimesencephalic cisterns in the remaining 3 patients. (orig.)

  5. Impact of product information and repeated exposure on consumer liking, sensory perception and concept associations of local apple juice

    DEFF Research Database (Denmark)

    Stolzenbach, Sandra; Bredie, Wender Laurentius Petrus; Christensen, Rune Haubo Bojesen

    2013-01-01

    The impact of product information and repeated exposure of local apple juice on consumer liking, sensory perception and concept associations was studied. Findings showed that consumers had high expectations towards the studied local apples juices. Consequently, the liking for the local apple juices...... did not fully determine consumer liking. Thus the sensory characteristics were also found to be of importance. Besides liking, the concept associations were also affected by product information. All local apple juices were associated as being more exclusive under informed tasting conditions....... No effects were found for liking of the apple juices over repeated exposure. Also, the consumers did not change their sensory perception over repeated consumption. However, the local apple juices were conceptualised as more familiar but remained exclusive after repeated consumption. When local producers have...

  6. Repeat Assessed Values Model for Housing Price Index

    Directory of Open Access Journals (Sweden)

    Carini Manuela

    2017-12-01

    Full Text Available This study proposes an innovative methodology, named Repeat Appraised Price Model (RAV, useful for determining the price index numbers for real estate markets and the corresponding index numbers of hedonic prices of main real estate characteristics in the case of a lack of data. The methodological approach proposed in this paper aims to appraise the time series of price index numbers. It integrates the principles of the method of repeat sales with the peculiarities of the Hedonic Price Method, overcoming the problem of an almost total absence of repeat sales for the same property in a given time range; on the other hand, the technique aims to overcome the limitation of the repeat sales technique concerning the inability to take into account the characteristics of individual properties.

  7. Diabetic Foot Prevention: Repeatability of the Loran Platform Plantar Pressure and Load Distribution Measurements in Nondiabetic Subjects during Bipedal Standing—A Pilot Study

    Directory of Open Access Journals (Sweden)

    Martha Zequera

    2011-01-01

    Full Text Available This study was designed to assess the repeatability of the Loran Platform and evaluate the variability of plantar pressure and postural balance, during barefoot standing in nondiabetic subjects, for future diabetic foot clinical evaluation. Measurements were taken for eight nondiabetic subjects (4 females, 4 males, aged 47±7.2 years who had no musculoskeletal symptoms. Five variables were measured with the platform in the barefoot standing position. Ten measurements were taken using two different techniques for feet and posture positioning, during three sessions, once a week. For most measurements, no significant effect over time was found with Student's t-test (P<.000125. The ANOVA test of statistical significance confirmed that measurement differences between subjects showed higher variations than measurements taken from the same subject (P<.001. The measurements taken by the Loran Platform system were found to be repeatable.

  8. The properties and interrelationships of various force-time parameters during maximal repeated rhythmic grip.

    Science.gov (United States)

    Nakada, Masakatsu; Demura, Shinichi; Yamaji, Shunsuke

    2007-01-01

    The purpose of this study was to examine the properties and interrelationships of various force-time parameters including the inflection point for the rate of decline in force during a maximal repeated rhythmic grip. Fifteen healthy males (age M=21.5, SD=2.1 yr, height M=172.4, SD=5.7 cm, body mass M=68.2, SD=9.2 kg) participated in this study. Subjects performed a maximal repeated rhythmic grip with maximal effort with a target frequency of 30 grip.min(-1) for 6 min. The force value decreased linearly and markedly until about 70% of maximal strength for about 55 s after the onset of a maximal repeated rhythmic grip, and then decreased moderately. Because all parameters showed fair or good correlations between 3 min and 6 min, they are considered to be able to sufficiently evaluate muscle endurance for 3 min instead of 6 min. However, there were significant differences between 3 min and 6 min in the integrated area, the final force, the rate of the decrement constant (k) fitting the force decreasing data to y=ae(-kx)+b and the force of maximal difference between the force and a straight line from peak force to the final force. Their parameters may vary generally by the length of a steady state, namely, a measurement time. The final force value before finishing and the rate of the decrement constant (k) reflect the latter phase during a maximal repeated rhythmic grip. Although many parameters show relatively high mutual relationships, the rate constant (k) shows relatively low correlations with other parameters. We inferred that decreasing the time until 80% of maximal strength and the amount of the decrement force for the first 1 min reflect a linear decrease in the initial phase.

  9. Repeated Predictable Stress Causes Resilience against Colitis-Induced Behavioral Changes in Mice

    Directory of Open Access Journals (Sweden)

    Ahmed M Hassan

    2014-11-01

    Full Text Available Inflammatory bowel disease is associated with an increased risk of mental disorders and can be exacerbated by stress. In this study which was performed with male 10-week old C57Bl/6N mice, we used dextran sulfate sodium (DSS-induced colitis to evaluate behavioral changes caused by intestinal inflammation, to assess the interaction between repeated psychological stress (water avoidance stress, WAS and colitis in modifying behavior, and to analyze neurochemical correlates of this interaction. A 7-day treatment with DSS (2 % in drinking water decreased locomotion and enhanced anxiety-like behavior in the open field test and reduced social interaction. Repeated exposure to WAS for 7 days had little influence on behavior but prevented the DSS-induced behavioral disturbances in the open field and social interaction tests. In contrast, repeated WAS did not modify colon length, colonic myeloperoxidase content and circulating proinflammatory cytokines, parameters used to assess colitis severity. DSS-induced colitis was associated with an increase in circulating neuropeptide Y (NPY, a rise in the hypothalamic expression of cyclooxygenase-2 mRNA and a decrease in the hippocampal expression of NPY mRNA, brain-derived neurotrophic factor mRNA and mineralocorticoid receptor mRNA. Repeated WAS significantly decreased the relative expression of corticotropin-releasing factor mRNA in the hippocampus. The effect of repeated WAS to blunt the DSS-evoked behavioral disturbances was associated with a rise of circulating corticosterone and an increase in the expression of hypothalamic NPY mRNA. These results show that experimental colitis leads to a particular range of behavioral alterations which can be prevented by repeated WAS, a model of predictable chronic stress, while the severity of colitis remains unabated. We conclude that the mechanisms underlying the resilience effect of repeated WAS involves hypothalamic NPY and the hypothalamic-pituitary-adrenal axis.

  10. Identification and characterization of short tandem repeats in the Tibetan macaque genome based on resequencing data.

    Science.gov (United States)

    Liu, San-Xu; Hou, Wei; Zhang, Xue-Yan; Peng, Chang-Jun; Yue, Bi-Song; Fan, Zhen-Xin; Li, Jing

    2018-07-18

    The Tibetan macaque, which is endemic to China, is currently listed as a Near Endangered primate species by the International Union for Conservation of Nature (IUCN). Short tandem repeats (STRs) refer to repetitive elements of genome sequence that range in length from 1-6 bp. They are found in many organisms and are widely applied in population genetic studies. To clarify the distribution characteristics of genome-wide STRs and understand their variation among Tibetan macaques, we conducted a genome-wide survey of STRs with next-generation sequencing of five macaque samples. A total of 1 077 790 perfect STRs were mined from our assembly, with an N50 of 4 966 bp. Mono-nucleotide repeats were the most abundant, followed by tetra- and di-nucleotide repeats. Analysis of GC content and repeats showed consistent results with other macaques. Furthermore, using STR analysis software (lobSTR), we found that the proportion of base pair deletions in the STRs was greater than that of insertions in the five Tibetan macaque individuals (Pgenome showed good amplification efficiency and could be used to study population genetics in Tibetan macaques. The neighbor-joining tree classified the five macaques into two different branches according to their geographical origin, indicating high genetic differentiation between the Huangshan and Sichuan populations. We elucidated the distribution characteristics of STRs in the Tibetan macaque genome and provided an effective method for screening polymorphic STRs. Our results also lay a foundation for future genetic variation studies of macaques.

  11. Repeatability of cervical joint flexion and extension within and between days

    DEFF Research Database (Denmark)

    Wang, Xu; Lindstroem, René; Plocharski, Maciej

    2018-01-01

    OBJECTIVE: The purpose of this study was to investigate within- and between-day repeatability of free and unrestricted healthy cervical flexion and extension motion when assessing dynamic cervical spine motion. METHODS: Fluoroscopy videos of 2 repeated cervical flexion and 2 repeated extension...

  12. Study on the homocysteine metabolism of patients with unexplained repeated spontaneous abortion

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Objective:To study the metabolism abnormality of homocysteine(Hcy) in unexplained repeated spontaneous abortion(URSA).Methods:The level of Hcy in sera was measured with hyperpressure liquid chromatography(HPLC);Folic acid and vitamin B12 were detected by radioimmune assay;anticardiolipin antibody (ACA) was detected by ELISA.Results:(1)The level of serum Hcy in URSA group was significantly higher than that in control group,showing a statistical significant difference(P<0.01).The level of Hcy was correlated with ages,but not correlated with areas,numbers of miscarriage,gestation age,primary or secondary abortions.(2)The levels of folic acid and vitamin B12 in URSA group were significantly lower than those in control group.The levels of serum folic acid and vitamin B12 were not correlated with age,area,numbers of miscarriage and abortion periods.(3)ACA positive rate in URSA was significantly higher than that in control group.The level of Hcy in ACA(+) group was significantly higher than that in ACA(-) group among URSA patients.Conclusions:Hyperhomocysteinemia,low folic acid state,and ACA were all the independent risk factors for URSA.Lacking of folic acid and vitamin B12 is one of the important causes of hyperhomocysteinemia.ACA and hyperhomocysteinemia may have synergistic action in the occurrence of URSA.

  13. Analysis of CR1 Repeats in the Zebra Finch Genome

    Directory of Open Access Journals (Sweden)

    George E. Liu

    2013-06-01

    Full Text Available Most bird species have smaller genomes and fewer repeats than mammals. Chicken Repeat 1 (CR1 repeat is one of the most abundant families of repeats, ranging from ~133,000 to ~187,000 copies accounting for ~50 to ~80% of the interspersed repeats in the zebra finch and chicken genomes, respectively. CR1 repeats are believed to have arisen from the retrotransposition of a small number of master elements, which gave rise to multiple CR1 subfamilies in the chicken. In this study, we performed a global assessment of the divergence distributions, phylogenies, and consensus sequences of CR1 repeats in the zebra finch genome. We identified and validated 34 CR1 subfamilies and further analyzed the correlation between these subfamilies. We also discovered 4 novel lineage-specific CR1 subfamilies in the zebra finch when compared to the chicken genome. We built various evolutionary trees of these subfamilies and concluded that CR1 repeats may play an important role in reshaping the structure of bird genomes.

  14. Large Polyglutamine Repeats Cause Muscle Degeneration in SCA17 Mice

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    Shanshan Huang

    2015-10-01

    Full Text Available In polyglutamine (polyQ diseases, large polyQ repeats cause juvenile cases with different symptoms than those of adult-onset patients, who carry smaller expanded polyQ repeats. The mechanisms behind the differential pathology mediated by different polyQ repeat lengths remain unknown. By studying knockin mouse models of spinal cerebellar ataxia-17 (SCA17, we found that a large polyQ (105 glutamines in the TATA-box-binding protein (TBP preferentially causes muscle degeneration and reduces the expression of muscle-specific genes. Direct expression of TBP with different polyQ repeats in mouse muscle revealed that muscle degeneration is mediated only by the large polyQ repeats. Different polyQ repeats differentially alter TBP’s interaction with neuronal and muscle-specific transcription factors. As a result, the large polyQ repeat decreases the association of MyoD with TBP and DNA promoters. Our findings suggest that specific alterations in protein interactions by large polyQ repeats may account for the unique pathology in juvenile polyQ diseases.

  15. Large Polyglutamine Repeats Cause Muscle Degeneration in SCA17 Mice

    Science.gov (United States)

    Huang, Shanshan; Yang, Su; Guo, Jifeng; Yan, Sen; Gaertig, Marta A.; Li, Shihua; Li, Xiao-Jiang

    2015-01-01

    SUMMARY In polyglutamine (polyQ) diseases, large polyQ repeats cause juvenile cases with different symptoms than adult-onset patients, who carry smaller expanded polyQ repeats. The mechanisms behind the differential pathology mediated by different polyQ repeat lengths remain unknown. By studying knock-in mouse models of spinal cerebellar ataxia-17 (SCA17), we found that a large polyQ (105 glutamines) in the TATA box-binding protein (TBP) preferentially causes muscle degeneration and reduces the expression of muscle-specific genes. Direct expression of TBP with different polyQ repeats in mouse muscle revealed that muscle degeneration is mediated only by the large polyQ repeats. Different polyQ repeats differentially alter TBP’s interaction with neuronal and muscle-specific transcription factors. As a result, the large polyQ repeat decreases the association of MyoD with TBP and DNA promoters. Our findings suggest that specific alterations in protein interactions by large polyQ repeats may account for the unique pathology in juvenile polyQ diseases. PMID:26387956

  16. Debiasing egocentrism and optimism biases in repeated competitions

    Directory of Open Access Journals (Sweden)

    Jason P. Rose

    2012-11-01

    Full Text Available When judging their likelihood of success in competitive tasks, people tend to be overoptimistic for easy tasks and overpessimistic for hard tasks (the shared circumstance effect; SCE. Previous research has shown that feedback and experience from repeated-play competitions has a limited impact on SCEs. However, in this paper, we suggest that competitive situations, in which the shared difficulty or easiness of the task is more transparent, will be more amenable to debiasing via repeated play. Pairs of participants competed in, made predictions about, and received feedback on, multiple rounds of a throwing task involving both easy- and hard-to-aim objects. Participants initially showed robust SCEs, but they also showed a significant reduction in bias after only one round of feedback. These and other results support a more positive view (than suggested from past research on the potential for SCEs to be debiased through outcome feedback.

  17. Effect of repeated freezing-thawing on the Achilles tendon of rabbits.

    Science.gov (United States)

    Chen, Lianxu; Wu, Yanping; Yu, Jiakuo; Jiao, Zhaode; Ao, Yingfang; Yu, Changlong; Wang, Jianquan; Cui, Guoqing

    2011-06-01

    The increased use of allograft tissue in the reconstruction of anterior cruciate ligament has brought more focus to the effect of storage and treatment on allograft. The purpose of this study was to observe the effect of histology and biomechanics on Achilles tendon in rabbits through repeated freezing-thawing before allograft tendon transplantation. Rabbit Achilles tendons were harvested and processed according to the manufacture's protocol of tissue bank, and freezing-thawing was repeated three times (group 1) and ten times (group 2). Those received only one cycle were used as controls. Then, tendons in each group were selected randomly to make for histological observations and biomechanics test. Histological observation showed that the following changes happened as the number of freezing-thawing increased: the arrangement of tendon bundles and collagen fibrils became disordered until ruptured, cells disrupted and apparent gaps appeared between tendon bundle because the formation of ice crystals. There were significant differences between the experimental and control groups in the values of maximum load, energy of maximum load and maximum stress, whereas no significant differences existed in other values such as stiffness, maximum strain, elastic modulus, and energy density. Therefore, repeated freezing-thawing had histological and biomechanical effect on Achilles tendon in rabbits before allograft tendon transplantation. This indicates that cautions should be taken in the repeated freezing-thawing preparation of allograft tendons in clinical application.

  18. Overcoming fixation with repeated memory suppression.

    Science.gov (United States)

    Angello, Genna; Storm, Benjamin C; Smith, Steven M

    2015-01-01

    Fixation (blocks to memories or ideas) can be alleviated not only by encouraging productive work towards a solution, but, as the present experiments show, by reducing counterproductive work. Two experiments examined relief from fixation in a word-fragment completion task. Blockers, orthographically similar negative primes (e.g., ANALOGY), blocked solutions to word fragments (e.g., A_L_ _GY) in both experiments. After priming, but before the fragment completion test, participants repeatedly suppressed half of the blockers using the Think/No-Think paradigm, which results in memory inhibition. Inhibiting blockers did not alleviate fixation in Experiment 1 when conscious recollection of negative primes was not encouraged on the fragment completion test. In Experiment 2, however, when participants were encouraged to remember negative primes at fragment completion, relief from fixation was observed. Repeated suppression may nullify fixation effects, and promote creative thinking, particularly when fixation is caused by conscious recollection of counterproductive information.

  19. Comparison of Repeated Measurement Design and Mixed Models in Evaluation of the Entonox Effect on Labor Pain

    Directory of Open Access Journals (Sweden)

    Nasim Karimi

    2017-01-01

    Full Text Available Background & objectives: In many medical studies, the response variable is measured repeatedly over time to evaluate the treatment effect that is known as longitudinal study. The analysis method for this type of data is repeated measures ANOVA that uses only one correlation structure and the results are not valid with inappropriate correlation structure. To avoid this problem, a convenient alternative is mixed models. So, the aim of this study was to compare of mixed and repeated measurement models for examination of the Entonox effect on the labor pain. Methods: This experimental study was designed to compare the effect of Entonox and oxygen inhalation on pain relief between two groups. Data were analyzed using repeated measurement and mixed models with different correlation structures. Selection and comparison of proper correlation structures performed using Akaike information criterion, Bayesian information criterion and restricted log-likelihood. Data were analyzed using SPSS-22. Results: Results of our study showed that all variables containing analgesia methods, labor duration of the first and second stages, and time were significant in these tests. In mixed model, heterogeneous first-order autoregressive, first-order autoregressive, heterogeneous Toeplitz and unstructured correlation structures were recognized as the best structures. Also, all variables were significant in these structures. Unstructured variance covariance matrix was recognized as the worst structure and labor duration of the first and second stages was not significant in this structure. Conclusions: This study showed that the Entonox inhalation has a significant effect on pain relief in primiparous and it is confirmed by all of the models.

  20. Combined Study of Titanium Dioxide Nanoparticle Transport and Toxicity on Microbial Nitrifying Communities under Single and Repeated Exposures in Soil Columns.

    Science.gov (United States)

    Simonin, Marie; Martins, Jean M F; Uzu, Gaëlle; Vince, Erwann; Richaume, Agnès

    2016-10-04

    Soils are exposed to nanoparticles (NPs) as a result of their increasing use in many commercial products. Adverse effects of NPs on soil microorganisms have been reported in several ecotoxicological studies using microcosms. Although repeated exposures are more likely to occur in soils, most of these previous studies were performed as a single exposure to NPs. Contrary to single contamination, the study of multiple NP contaminations in soils requires the use of specialized setups. Using a soil column experiment, we compared the influence of single and repeated exposures (one, two, or three exposures that resulted in the same final concentration applied) on the transport of titanium dioxide (TiO 2 ) NPs through soil and the effect of these different exposure scenarios on the abundance and activity of soil nitrifying microbial communities after a 2 month incubation. The transport of TiO 2 NPs was very limited under both single and repeated exposures and was highest for the lowest concentration injected during the first application. Significant decreases in nitrification activity and ammonia-oxidizing archaea and bacteria populations were observed only for the repeated exposure scenario (three TiO 2 NP contaminations). These results suggest that, under repeated exposures, the transport of TiO 2 NPs to deep soil layers and groundwater is limited and that a chronic contamination is more harmful for the soil microbiological functioning than a single exposure.

  1. Acute toxicity and the 28-day repeated dose study of a Siddha medicine Nuna Kadugu in rats

    Directory of Open Access Journals (Sweden)

    Ramaswamy Ramaswamy

    2012-10-01

    Full Text Available Abstract Background Nuna Kadugu (NK, a Siddha medicine prepared from leaves and fruits of Morinda Pubescens, used for the treatment of various skin diseases. Though NK has been widely used for several decades, no scientific report was available on its safety. Present study was undertaken to demonstrate the oral toxicity of NK in Sprague Dawley rats. Methods Acute and 28-day repeated oral toxicity studies were performed following OECD test guidelines 423 and 407, respectively, with minor modifications. In acute oral toxicity study, NK was administered at 2000mg/kg b.wt., p.o and animals were observed for toxic signs at 0, 0.5, 1, 4, 24 h and for next 14 days. Gross pathology was performed at the end of the study. In repeated dose, the 28- day oral toxicity study, NK was administered at 300, 600 and 900 mg/kg b.wt./p.o/day. Two satellite groups (control and high dose were also maintained to determine the delayed onset toxicity of NK. Animals were observed for mortality, morbidity, body weight changes, feed and water intake. Haematology, clinical biochemistry, electrolytes, gross pathology, relative organ weight and histopathological examination were performed. Results In acute toxicity study, no treatment related death or toxic signs were observed with NK administration. In the repeated dose study, no significant differences in body weight changes, food / water intake, haematology, clinical biochemistry and electrolytes content were observed between control and NK groups. No gross pathological findings and difference in relative organ weights were observed between control and NK treated rats. Histopathological examination revealed no abnormalities with NK treatment. Conclusion Acute study reveals that the LD50 of NK is greater than 2000mg/kg, b.wt. in fasted female rats and can be classified as Category 5. 28-day repeated oral toxicity demonstrates that the No Observed Adverse Effect Level of NK is greater than 900 mg/kg b.wt./day, p.o in rats

  2. Repeated cognitive stimulation alleviates memory impairments in an Alzheimer's disease mouse model.

    Science.gov (United States)

    Martinez-Coria, Hilda; Yeung, Stephen T; Ager, Rahasson R; Rodriguez-Ortiz, Carlos J; Baglietto-Vargas, David; LaFerla, Frank M

    2015-08-01

    Alzheimer's disease is a neurodegenerative disease associated with progressive memory and cognitive decline. Previous studies have identified the benefits of cognitive enrichment on reducing disease pathology. Additionally, epidemiological and clinical data suggest that repeated exercise, and cognitive and social enrichment, can improve and/or delay the cognitive deficiencies associated with aging and neurodegenerative diseases. In the present study, 3xTg-AD mice were exposed to a rigorous training routine beginning at 3 months of age, which consisted of repeated training in the Morris water maze spatial recognition task every 3 months, ending at 18 months of age. At the conclusion of the final Morris water maze training session, animals subsequently underwent testing in another hippocampus-dependent spatial task, the Barnes maze task, and on the more cortical-dependent novel object recognition memory task. Our data show that periodic cognitive enrichment throughout aging, via multiple learning episodes in the Morris water maze task, can improve the memory performance of aged 3xTg-AD mice in a separate spatial recognition task, and in a preference memory task, when compared to naïve aged matched 3xTg-AD mice. Furthermore, we observed that the cognitive enrichment properties of Morris water maze exposer, was detectable in repeatedly trained animals as early as 6 months of age. These findings suggest early repeated cognitive enrichment can mitigate the diverse cognitive deficits observed in Alzheimer's disease. Published by Elsevier Inc.

  3. Harry Potter and "the Landscape of Consciousness": Repeat Home Viewers' Understandings about Character

    Science.gov (United States)

    Finch, Brian

    2012-01-01

    Many children view favourite feature films repeatedly at home and develop understandings of them. This article discusses findings from a study which focused on the understandings that 9- and 10-year-old children showed about character in "Harry Potter and the Chamber of Secrets." These findings are reported in terms of a framework…

  4. Huntingtin gene repeat size variations affect risk of lifetime depression.

    Science.gov (United States)

    Gardiner, Sarah L; van Belzen, Martine J; Boogaard, Merel W; van Roon-Mom, Willeke M C; Rozing, Maarten P; van Hemert, Albert M; Smit, Johannes H; Beekman, Aartjan T F; van Grootheest, Gerard; Schoevers, Robert A; Oude Voshaar, Richard C; Roos, Raymund A C; Comijs, Hannie C; Penninx, Brenda W J H; van der Mast, Roos C; Aziz, N Ahmad

    2017-12-11

    Huntington disease (HD) is a severe neuropsychiatric disorder caused by a cytosine-adenine-guanine (CAG) repeat expansion in the HTT gene. Although HD is frequently complicated by depression, it is still unknown to what extent common HTT CAG repeat size variations in the normal range could affect depression risk in the general population. Using binary logistic regression, we assessed the association between HTT CAG repeat size and depression risk in two well-characterized Dutch cohorts─the Netherlands Study of Depression and Anxiety and the Netherlands Study of Depression in Older Persons─including 2165 depressed and 1058 non-depressed persons. In both cohorts, separately as well as combined, there was a significant non-linear association between the risk of lifetime depression and HTT CAG repeat size in which both relatively short and relatively large alleles were associated with an increased risk of depression (β = -0.292 and β = 0.006 for the linear and the quadratic term, respectively; both P < 0.01 after adjustment for the effects of sex, age, and education level). The odds of lifetime depression were lowest in persons with a HTT CAG repeat size of 21 (odds ratio: 0.71, 95% confidence interval: 0.52 to 0.98) compared to the average odds in the total cohort. In conclusion, lifetime depression risk was higher with both relatively short and relatively large HTT CAG repeat sizes in the normal range. Our study provides important proof-of-principle that repeat polymorphisms can act as hitherto unappreciated but complex genetic modifiers of depression.

  5. Fourteen Annually Repeated Droughts Suppressed Autotrophic Soil Respiration and Resulted in an Ecosystem Change

    NARCIS (Netherlands)

    Kopittke, G.R.; Tietema, A.; van Loon, E.; Asscheman, D.

    2014-01-01

    Predictions of future climate over the next 100 years show that the frequency of long periods of droughts in summer will increase in the Netherlands. This study investigated the effect of 14 annually repeated droughts on soil respiration at a Dutch heathland. Field measurements of total soil

  6. Topological characteristics of helical repeat proteins

    NARCIS (Netherlands)

    Groves, M R; Barford, D

    The recent elucidation of protein structures based upon repeating amino acid motifs, including the armadillo motif, the HEAT motif and tetratricopeptide repeats, reveals that they belong to the class of helical repeat proteins. These proteins share the common property of being assembled from tandem

  7. The need for repeat angiography in subarachnoid haemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Urbach, H; Solymosi, L [Department of Neuroradiology, University of Bonn, Sigmund-Freud-Strasse 25, D-53127 Bonn (Germany); Zentner, J [Department of Neurosurgery, University of Bonn, Sigmund-Freud-Strasse 25, D-53127 Bonn (Germany)

    1998-01-01

    This study was designed to assess the necessity for a second angiogram study in patients in whom initial angiography after primary subarachnoid haemorrhage (SAH) was negative. During a 12-year period, 122 of 694 patients (17.5 %) had negative initial angiograms. CT, available for 98 patients, showed a preponderance of subarachnoid blood in the perimesencephalic cisterns in 50 of 73 patients (68.5 %) in whom blood was visible on CT. Angiography, repeated in 67 patients, revealed an aneurysm in 4 (6 %): 2 had an aneurysm of the anterior communicating artery, 1 of the posterior inferior cerebellar artery, and 1 of the P2 segment of the posterior cerebral artery. CT showed subarachnoid blood in the interpeduncular and ambient cisterns in this last case, and a preponderance of subarachnoid blood outside the perimesencephalic cisterns in the remaining 3 patients. (orig.) With 2 figs., 1 tab., 32 refs.

  8. Natively Unfolded FG Repeats Stabilize the Structure of the Nuclear Pore Complex.

    Science.gov (United States)

    Onischenko, Evgeny; Tang, Jeffrey H; Andersen, Kasper R; Knockenhauer, Kevin E; Vallotton, Pascal; Derrer, Carina P; Kralt, Annemarie; Mugler, Christopher F; Chan, Leon Y; Schwartz, Thomas U; Weis, Karsten

    2017-11-02

    Nuclear pore complexes (NPCs) are ∼100 MDa transport channels assembled from multiple copies of ∼30 nucleoporins (Nups). One-third of these Nups contain phenylalanine-glycine (FG)-rich repeats, forming a diffusion barrier, which is selectively permeable for nuclear transport receptors that interact with these repeats. Here, we identify an additional function of FG repeats in the structure and biogenesis of the yeast NPC. We demonstrate that GLFG-containing FG repeats directly bind to multiple scaffold Nups in vitro and act as NPC-targeting determinants in vivo. Furthermore, we show that the GLFG repeats of Nup116 function in a redundant manner with Nup188, a nonessential scaffold Nup, to stabilize critical interactions within the NPC scaffold needed for late steps of NPC assembly. Our results reveal a previously unanticipated structural role for natively unfolded GLFG repeats as Velcro to link NPC subcomplexes and thus add a new layer of connections to current models of the NPC architecture. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. In silico reversal of repeat-induced point mutation (RIP identifies the origins of repeat families and uncovers obscured duplicated genes

    Directory of Open Access Journals (Sweden)

    Hane James K

    2010-11-01

    Full Text Available Abstract Background Repeat-induced point mutation (RIP is a fungal genome defence mechanism guarding against transposon invasion. RIP mutates the sequence of repeated DNA and over time renders the affected regions unrecognisable by similarity search tools such as BLAST. Results DeRIP is a new software tool developed to predict the original sequence of a RIP-mutated region prior to the occurrence of RIP. In this study, we apply deRIP to the genome of the wheat pathogen Stagonospora nodorum SN15 and predict the origin of several previously uncharacterised classes of repetitive DNA. Conclusions Five new classes of transposon repeats and four classes of endogenous gene repeats were identified after deRIP. The deRIP process is a new tool for fungal genomics that facilitates the identification and understanding of the role and origin of fungal repetitive DNA. DeRIP is open-source and is available as part of the RIPCAL suite at http://www.sourceforge.net/projects/ripcal.

  10. Joint Ordering and Pricing Decisions for New Repeat-Purchase Products

    Directory of Open Access Journals (Sweden)

    Xiang Wu

    2015-01-01

    Full Text Available This paper studies ordering and pricing problems for new repeat-purchase products. We incorporate the repeat-purchase rate and price effects into the Bass model to characterize the demand pattern. We consider two decision models: (1 two-stage decision model, in which the sales division chooses a price to maximize the gross profit and the purchasing division determines an optimal ordering decision to minimize the total cost under a given demand subsequently, and (2 joint decision model, in which the firm makes ordering and pricing decisions simultaneously to maximize the profit. We combine the generalized Bass model with dynamic lot sizing model to formulate the joint decision model. We apply both models to a specific imported food provided by an online fresh produce retailer in Central China, solve them by Gaussian Random-Walk and Wagner-Whitin based algorithms, and observe three results. First, joint pricing and ordering decisions bring more significant profits than making pricing and ordering decisions sequentially. Second, a great initiative in adoption significantly increases price premium and profit. Finally, the optimal price shows a U-shape (i.e., decreases first and increases later relationship and the profit increases gradually with the repeat-purchase rate when it is still not very high.

  11. Impact of repeated insecticide application on soil microbial activity

    International Nuclear Information System (INIS)

    Xu Bujin; Zhang Yongxi; Chen Meici; Zhu Nanwen; Ming Hong

    2001-01-01

    The effects of repeated insecticide application on soil microbial activity were studied both in a cotton field and in the laboratory. The results of experiment show that there are some effects on soil microbial activities, such as the population of soil microorganisms, soil respiration, dehydrogenase activity and nitrogen fixation. The degree of effects depends on the chemical dosage. Within the range of 0.5-10.0 μg/g air-dry-soil, the higher the concentration, the stronger effect. In this experiment, the effect disappeared within 4, 8 or 16 days after treatment, depending on the dose applied. In field conditions, the situation is more complex and the data of field experiment show greater fluctuation. (author)

  12. Sleep-effects on implicit and explicit memory in repeated visual search.

    Science.gov (United States)

    Geyer, Thomas; Mueller, Hermann J; Assumpcao, Leonardo; Gais, Steffen

    2013-01-01

    In repeated visual search tasks, facilitation of reaction times (RTs) due to repetition of the spatial arrangement of items occurs independently of RT facilitation due to improvements in general task performance. Whereas the latter represents typical procedural learning, the former is a kind of implicit memory that depends on the medial temporal lobe (MTL) memory system and is impaired in patients with amnesia. A third type of memory that develops during visual search is the observers' explicit knowledge of repeated displays. Here, we used a visual search task to investigate whether procedural memory, implicit contextual cueing, and explicit knowledge of repeated configurations, which all arise independently from the same set of stimuli, are influenced by sleep. Observers participated in two experimental sessions, separated by either a nap or a controlled rest period. In each of the two sessions, they performed a visual search task in combination with an explicit recognition task. We found that (1) across sessions, MTL-independent procedural learning was more pronounced for the nap than rest group. This confirms earlier findings, albeit from different motor and perceptual tasks, showing that procedural memory can benefit from sleep. (2) Likewise, the sleep group compared with the rest group showed enhanced context-dependent configural learning in the second session. This is a novel finding, indicating that the MTL-dependent, implicit memory underlying contextual cueing is also sleep-dependent. (3) By contrast, sleep and wake groups displayed equivalent improvements in explicit recognition memory in the second session. Overall, the current study shows that sleep affects MTL-dependent as well as MTL-independent memory, but it affects different, albeit simultaneously acquired, forms of MTL-dependent memory differentially.

  13. Microsatellite instability at a tetranucleotide repeat in type I endometrial carcinoma

    Directory of Open Access Journals (Sweden)

    Choi Ho

    2008-12-01

    Full Text Available Abstract Background Microsatellite instability (MSI at tri- or tetranucleotide repeat markers (elevated microsatellite alterations at selected tetranucleotide repeat, EMAST has been recently described. But, the underlying genetic mechanism of EMAST is unclear. This study was to investigate the prevalence of EMAST, in type I endometrial carcinoma, and to determine the correlation between the MSI status and mismatch repair genes (MMR or p53. Methods We examined the 3 mono-, 3 di-, and 6 tetranucleotide repeat markers by PCR in 39 cases of type I endometrial carcinoma and performed the immunohistochemistry of hMSH2, hMLH1, and p53 protein. Results More than two MSI at mono- and dinucleotide repeat markers was noted in 8 cases (MSI-H, 20.5%. MSI, at a tetranucleotide repeat, was detected in 15 cases (EMAST, 38.5%. In remaining 16 cases, any MSI was not observed. (MSS, 42.1%, MSI status was not associated with FIGO stage, grade or depth of invasion. The absence of expression of either one of both hMSH2 or hMLH1 was noted in seven (87.5% of eight MSI-H tumors, one (6.3% of 16 MSS tumors, and five (33.3% of 15 EMAST tumors. (p = 0.010 The expression of p53 protein was found in one (12.5% of eight MSI-H tumors, five (31.3% of 16 MSS tumors, and seven of 15 EMAST tumors. (p = 0.247 Conclusion Our results showed that about 38.5% of type I endometrial carcinomas exhibited EMAST, and that EMAST was rarely associated with alteration of hMSH2 or hMLH1.

  14. UK 2009-2010 repeat station report

    Directory of Open Access Journals (Sweden)

    Thomas J.G. Shanahan

    2013-03-01

    Full Text Available The British Geological Survey is responsible for conducting the UK geomagnetic repeat station programme. Measurements made at the UK repeat station sites are used in conjunction with the three UK magnetic observatories: Hartland, Eskdalemuir and Lerwick, to produce a regional model of the local field each year. The UK network of repeat stations comprises 41 stations which are occupied at approximately 3-4 year intervals. Practices for conducting repeat station measurements continue to evolve as advances are made in survey instrumentation and as the usage of the data continues to change. Here, a summary of the 2009 and 2010 UK repeat station surveys is presented, highlighting the measurement process and techniques, density of network, reduction process and recent results.

  15. Neonates' responses to repeated exposure to a still face.

    Science.gov (United States)

    Nagy, Emese; Pilling, Karen; Watt, Rachel; Pal, Attila; Orvos, Hajnalka

    2017-01-01

    The main aims of the study were to examine whether human neonates' responses to communication disturbance modelled by the still-face paradigm were stable and whether their responses were affected by their previous experience with the still-face paradigm. The still face procedure, as a laboratory model of interpersonal stress, was administered repeatedly, twice, to 84 neonates (0 to 4 day olds), with a delay of an average of 1.25 day. Frame-by-frame analysis of the frequency and duration of gaze, distressed face, crying, sleeping and sucking behaviours showed that the procedure was stressful to them both times, that is, the still face effect was stable after repeated administration and newborns consistently responded to such nonverbal violation of communication. They averted their gaze, showed distress and cried more during the still-face phase in both the first and the second administration. They also showed a carry-over effect in that they continued to avert their gaze and displayed increased distress and crying in the first reunion period, but their gaze behaviour changed with experience, in the second administration. While in the first administration the babies continued averting their gaze even after the stressful still-face phase was over, this carry-over effect disappeared in the second administration, and the babies significantly increased their gaze following the still-face phase. After excluding explanations of fatigue, habituation and random effects, a self-other regulatory model is discussed as a possible explanation for this pattern.

  16. Acute exercise attenuates negative affect following repeated sad mood inductions in persons who have recovered from depression.

    Science.gov (United States)

    Mata, Jutta; Hogan, Candice L; Joormann, Jutta; Waugh, Christian E; Gotlib, Ian H

    2013-02-01

    Identifying factors that may protect individuals from developing Major Depressive Disorder (MDD) in the face of stress is critical. In the current study we experimentally tested whether such a potentially protective factor, engaging in acute exercise, reduces the adverse effects of repeated sad mood inductions in individuals who have recovered from depression. We hypothesized that recovered depressed participants who engage in acute exercise report a smaller increase in negative affect (NA) and a smaller decrease in positive affect (PA) when exposed to a repeated sad mood induction (i.e., habituation), whereas participants who do not exercise show sensitization (i.e., increased NA and decreased PA in response to a repeated adverse stimulus). Forty-one women recovered from MDD and 40 healthy control women were randomly assigned to either exercise for 15 minutes or quiet rest. Afterward, participants were exposed to two sad mood inductions and reported their levels of affect throughout the study. Recovered depressed participants who had not exercised exhibited higher NA after the second sad mood induction, a finding consistent with sensitization. In contrast, both recovered depressed participants who had engaged in acute exercise and healthy control participants showed no increase in NA in response to the repeated sad mood induction. Participants who exercised reported higher PA after the exercise bout; however, our hypothesis concerning reported PA trajectories following the sad mood inductions was not supported. Results suggest that exercise can serve as a protective factor in the face of exposure to repeated emotional stressors, particularly concerning NA in individuals who have recovered from depression. 2013 APA, all rights reserved

  17. Deletion of Repeats in the Alpha C Protein Enhances the Pathogenicity of Group B Streptococci in Immune Mice

    OpenAIRE

    Gravekamp, C.; Rosner, Bernard; Madoff, L. C.

    1998-01-01

    The alpha C protein is a protective surface-associated antigen of group B streptococci (GBS). The prototype alpha C protein of GBS (strain A909) contains nine identical tandem repeats, each comprising 82 amino acids, flanked by N- and C-terminal domains. Clinical isolates of GBS show variable numbers of repeats with a normal distribution and a median of 9 to 10 repeats. Here, we show that escape mutants of GBS expressing one-repeat alpha C protein were 100-fold more pathogenic than GBS expres...

  18. Impact of the 'Providing Access to Continued Education' Programme on Repeat Teenage Pregnancy in the Bahamas.

    Science.gov (United States)

    Sakharkar, V P; Frankson, M A; Sakharkar, P R

    2015-05-15

    To determine the relationship of determinants such as age, ethnicity, education and sexual behaviour with repeat teenage pregnancy and to determine the impact of 'Providing Access to Continued Education' (PACE) programme in reducing repeat teenage pregnancy amongst its participants in The Bahamas. This retrospective cohort study included 397 attendees of the Adolescent Health Centre (AHC). Eighty-eight out of 139 registered participants completed the PACE programme. Data on age, ethnicity, education, sexual behaviour and repeat pregnancy in two years were analysed for descriptive statistics, and association of demographic characteristics and participation in the PACE programme with repeat pregnancy using the Chi-squared test. Mean age of participants was 16.4 ± 1.1 years; median school grade and mean grade point average (GPA) was 11 and 1.97 ± 0.7, respectively. The mean age at the first sexual activity was 14.9 ± 1.2 years. The mean age and number of sexual partners were 21 ± 4.3 years and 2 ± 1, respectively. Overall, repeat pregnancy rate was 39%: 37.4% amongst PACE registered and 31.8% amongst PACE completed mothers. No significant difference was observed in repeat pregnancy between registered and non-registered as well as those who completed the programme and those who did not. The odds ratio of 0.525 suggested that completion of the PACE programme had a moderate protective effect on reducing repeat pregnancy. Age, ethnicity, education and sexual behaviour showed no association with repeat pregnancy. The PACE programme did not reduce repeat pregnancy rate significantly. However, completion of the programme offered a moderate protection.

  19. Reject/repeat analysis and the effect prior film viewing has on a department's reject/repeat rate

    International Nuclear Information System (INIS)

    Clark, P.A.; Hogg, P.

    2003-01-01

    Purpose: Achieving cost-effectiveness within the NHS is an old initiative but one that has again been highlighted by recent government policies (The New NHS-Modern and Dependable, Stationary Office, London, 1997). It has been reiterated that it is the responsibility of individual Trusts to devise means to provide such a service. Reject/repeat analyses have long been the primary tool used to assess the cost-effectiveness of radiography departments (Quality Assurance in Diagnostic Radiology, WHO, Geneva, 1982). This research paper examines an in-house initiative (viewing patients' previous films) commonly employed in other Health Trusts in order to reduce departmental repeat/reject rates. Method: Three hundred orthopaedic patients with hip, knee and ankle prostheses were included in a reject/repeat analysis. The aim was to investigate whether or not viewing patient's previous relevant radiographs would be advantageous to the practicing radiographer. This was done through an audit cycle consisting of two audit periods each lasting for 3 months. The primary audit period recorded the baseline repeat/reject rate, with the secondary audit period recording the repeat/reject rate under an experimental condition of viewing the relevant radiographs. Results: The baseline audit revealed repeat rates of 33% in orthopaedic patients with hip, knee and ankle prostheses. The availability of prior film viewing to the radiographer reduced this repeat rate to 10.6%. Conclusion: Prior film viewing dramatically reduced the department's repeat/reject rate by 22.4%. This provides scope for significant patient dose reductions as well as reducing departmental film expenses. This is an underestimated initiative and should be used appropriately in routine clinical practice

  20. Repeatability of nest morphology in African weaver birds.

    Science.gov (United States)

    Walsh, Patrick T; Hansell, Mike; Borello, Wendy D; Healy, Susan D

    2010-04-23

    It is generally assumed that birds build nests according to a genetic 'template', little influenced by learning or memory. One way to confirm the role of genetics in nest building is to assess the repeatability of nest morphology with repeated nest attempts. Solitary weaver birds, which build multiple nests in a single breeding season, are a useful group with which to do this. Here we show that repeatability of nest morphology was low, but significant, in male Southern Masked weaver birds and not significant in the Village weavers. The larger bodied Village weavers built larger nests than did Southern Masked weavers, but body size did not explain variation in Southern Masked weaver nest dimensions. Nests built by the same male in both species got shorter and lighter as more nests were constructed. While these data demonstrate the potential for a genetic component of variation in nest building in solitary weavers, it is also clear that there remains plenty of scope in both of these species for experience to shape nest construction.

  1. Evaluation of the repeated-dose liver micronucleus assay using 2,4-dinitrotoluene: a report of a collaborative study by CSGMT/JEMS.MMS.

    Science.gov (United States)

    Maeda, Akihisa; Tsuchiyama, Hiromi; Asaoka, Yoshiji; Hirakata, Mikito; Miyoshi, Tomoya; Oshida, Keiyu; Miyamoto, Yohei

    2015-03-01

    The liver micronucleus assay using young adult rats has the potential to detect liver carcinogens by repeated dosing, and could be expected to be integrated into repeated-dose toxicity studies using a hepatocyte isolation method without the traditional in situ collagenase perfusion. In this study, to assess the performance of the repeated-dose liver micronucleus assay, 2,4-dinitrotoluene (DNT), which is a rodent liver carcinogen, was administered orally to male rats at doses of 50, 100 and 200 mg/kg/day once daily for 14 or 28 consecutive days, and the frequencies of micronucleated hepatocytes (MNHEPs) and micronucleated immature erythrocytes (MNIMEs) were examined. Significant increases in the MNHEPs were observed at 50 mg/kg/day or more in the 14-day treatment, and 50 and 100 mg/kg/day in the 28-day treatment. These increases were dependent on both the dose and the number of administrations, which indicates the possibility that the MNHEPs accumulate as a result of repeated dosing. In contrast, no increase in the MNIMEs was observed. In conclusion, the repeated-dose liver micronucleus assay using young adult rats is sufficiently sensitive to detect the genotoxicity of 2,4-DNT at a low dose.

  2. Reasons of repeat dental treatment under general anaesthesia: A retrospective study.

    Science.gov (United States)

    Guidry, J; Bagher, S; Felemban, O; Rich, A; Loo, C

    2017-12-01

    The purpose of this chart review study was to investigate the common factors that exist in paediatric patients requiring a repeat dental treatment under general anaesthesia (GA2) within four years after the initial dental treatment under general anaesthesia (GA1). The Electronic Health Records of one to 12 year-old children who received dental treatment under general anaesthesia (GA) between April 2004 and October 2009 were identified and analysed by a single examiner. Children who had GA2, within a four year period following GA1 were categorised as cases. Children who had only one dental treatment under GA were considered the control pool. Each case was matched to three controls based on sex and age range at GA1 of ± 6 months. Other recorded variables included: date of birth, date of GAs (GA1 and GA2 for cases; GA1 for controls), type of payment, dmfs before GA1, dental treatments provided under GA, return of 1-week post-GA1 follow-up, frequency of recare/recall visits following one-year post-GA1 visit and the type and frequency of post GA1 emergency visits. Out of 581 subjects, 29 (4.99%) cases were matched to 87 controls. Medically compromised patients had four times the risk of GA2. At GA1, cases received statistically significant less sealants (p=0.026), less extractions (pdental treatment under general anaesthesia were more likely to have a repeat dental treatment under general anaesthesia within 4 years.

  3. The effect of repeated measurements and working memory on the most comfortable level in the ANL test.

    Science.gov (United States)

    Brännström, K Jonas; Olsen, Steen Østergaard; Holm, Lucas; Kastberg, Tobias; Ibertsson, Tina

    2014-11-01

    To study the effect of a large number of repetitions on the most comfortable level (MCL) when doing the acceptable noise level (ANL) test, and explore if MCL variability is related to central cognitive processes. Twelve MCL repetitions were measured within the ANL test using interleaved methodology during one session using a non-semantic version. Phonological (PWM) and visuospatial working memory (VSWM) was measured. Thirty-two normal-hearing adults. Repeated measures ANOVA, intraclass correlations, and the coefficient of repeatability (CR) were used to assess the repeatability. Repeated measures ANOVA and CR indicated poor agreement between the two first repetitions. After excluding the first repetition, analyses showed that the MCL in the ANL test is reliable. A negative association was found between PWM and MCL variability indicating that subjects with higher PWM show less variability. The findings suggest that, after excluding the first repetition, the MCL in the ANL test is reliable. A single repetition of the MCL in the ANL test should be avoided. If an interleaved methodology is used, a single ANL repetition should be added prior to the actual testing. The findings also suggest that MCL variability is associated to PWM but not VSWM.

  4. Repeatability of an automated Landolt C test, compared with the early treatment of diabetic retinopathy study (ETDRS) chart testing.

    Science.gov (United States)

    Ruamviboonsuk, Paisan; Tiensuwan, Montip; Kunawut, Catleya; Masayaanon, Patcharapim

    2003-10-01

    To evaluate the repeatability of visual acuity scores from the automated test and compare them with the Early Treatment of Diabetic Retinopathy Study (ETDRS) chart. Instrument validation study based on a model of repeatability study in two observations. SMETHODS: a prospective, clinic-based, comparative study. A total of 206 participants without ocular diseases and refractive errors in their right eyes were randomly enrolled in the automated group in which 107 participants performed the automated test and the ETDRS group in which 99 participants read the ETDRS chart. All participants were tested with only their right eyes without corrections at 4 meters and came back to have the same tests 1 week later. The automated test used the Landolt rings as optotypes and was conducted by a low-ended personal computer with a 15-inch monitor and a wireless keyboard. The "letter" score calculated by counting every correct response to optotypes, and the "threshold curve" score interpreted from the optotype size at the midpoint of a visual acuity threshold curve. The 95% confidence interval of test-retest of visual acuity scores from the automated test are comparable to the ETDRS chart (.143 compared with.125 for letter scores,.145 compared with.122 for threshold curve scores). The score repeatabilities, calculated from the standard deviations of test-retest, from the automated test are also comparable to the ETDRS chart (.201 compared with.177 for letter scores,.206 compared with.172 for threshold curve scores). All comparisons demonstrated no statistical difference (P >.05). The automated testing system in this study enables practical measuring visual acuity by the Landolt rings. The system's repeatability, which is comparable to the ETDRS chart, supports its role as an alternative tool for measuring outcome in new clinical research. Its ability to practically generate visual acuity threshold curves may also be useful in future clinical research studies.

  5. A high stability and repeatability electrochemical scanning tunneling microscope.

    Science.gov (United States)

    Xia, Zhigang; Wang, Jihao; Hou, Yubin; Lu, Qingyou

    2014-12-01

    We present a home built electrochemical scanning tunneling microscope (ECSTM) with very high stability and repeatability. Its coarse approach is driven by a closely stacked piezo motor of GeckoDrive type with four rigid clamping points, which enhances the rigidity, compactness, and stability greatly. It can give high clarity atomic resolution images without sound and vibration isolations. Its drifting rates in XY and Z directions in solution are as low as 84 pm/min and 59 pm/min, respectively. In addition, repeatable coarse approaches in solution within 2 mm travel distance show a lateral deviation less than 50 nm. The gas environment can be well controlled to lower the evaporation rate of the cell, thus reducing the contamination and elongating the measurement time. Atomically resolved SO4(2-) image on Au (111) work electrode is demonstrated to show the performance of the ECSTM.

  6. Self-compassionate young adults show lower salivary alpha-amylase responses to repeated psychosocial stress.

    Science.gov (United States)

    Breines, Juliana G; McInnis, Christine M; Kuras, Yuliya I; Thoma, Myriam V; Gianferante, Danielle; Hanlin, Luke; Chen, Xuejie; Rohleder, Nicolas

    2015-10-01

    In this study we tested the hypothesis that participants higher in dispositional self-compassion would show lower stress-induced reactivity of salivary alpha-amylase (sAA), a marker of sympathetic nervous system activation. Thirty-three healthy participants (18-34 years old) were exposed to a standardized laboratory stressor on two consecutive days. Self-compassion, self-esteem, and demographic factors were assessed by questionnaire and sAA was assessed at baseline and at 1, 10, 30, and 60 minutes following each stressor. Self-compassion was a significant negative predictor of sAA responses on both days. This relationship remained significant when controlling for self-esteem, subjective distress, age, gender, ethnicity, and Body Mass Index (BMI). These results suggest that self-compassion may serve as a protective factor against stress-induced physiological changes that have implications for health.

  7. Base excision repair of chemotherapeutically-induced alkylated DNA damage predominantly causes contractions of expanded GAA repeats associated with Friedreich's ataxia.

    Directory of Open Access Journals (Sweden)

    Yanhao Lai

    Full Text Available Expansion of GAA·TTC repeats within the first intron of the frataxin gene is the cause of Friedreich's ataxia (FRDA, an autosomal recessive neurodegenerative disorder. However, no effective treatment for the disease has been developed as yet. In this study, we explored a possibility of shortening expanded GAA repeats associated with FRDA through chemotherapeutically-induced DNA base lesions and subsequent base excision repair (BER. We provide the first evidence that alkylated DNA damage induced by temozolomide, a chemotherapeutic DNA damaging agent can induce massive GAA repeat contractions/deletions, but only limited expansions in FRDA patient lymphoblasts. We showed that temozolomide-induced GAA repeat instability was mediated by BER. Further characterization of BER of an abasic site in the context of (GAA20 repeats indicates that the lesion mainly resulted in a large deletion of 8 repeats along with small expansions. This was because temozolomide-induced single-stranded breaks initially led to DNA slippage and the formation of a small GAA repeat loop in the upstream region of the damaged strand and a small TTC loop on the template strand. This allowed limited pol β DNA synthesis and the formation of a short 5'-GAA repeat flap that was cleaved by FEN1, thereby leading to small repeat expansions. At a later stage of BER, the small template loop expanded into a large template loop that resulted in the formation of a long 5'-GAA repeat flap. Pol β then performed limited DNA synthesis to bypass the loop, and FEN1 removed the long repeat flap ultimately causing a large repeat deletion. Our study indicates that chemotherapeutically-induced alkylated DNA damage can induce large contractions/deletions of expanded GAA repeats through BER in FRDA patient cells. This further suggests the potential of developing chemotherapeutic alkylating agents to shorten expanded GAA repeats for treatment of FRDA.

  8. THE EFFECTS OF SINGLE VERSUS REPEATED PLYOMETRICS ON LANDING BIOMECHANICS AND JUMPING PERFORMANCE IN MEN

    Directory of Open Access Journals (Sweden)

    H. Makaruk

    2014-07-01

    Full Text Available The aim of this study was to examine the chronic effects of single and repeated jumps training on vertical landing force (VGRF and jump height in untrained men. The VGRF and jump height were compared after a six-week plyometric training programme containing single and repeated jumps, together with two additional parameters: landing time (LT and range of the knee flexion during landing (KF. Thirty-six untrained physical education students with a plyometric training background were randomly assigned to a single jump group (SJG, n =12, repeated jumps group (RJG, n =12, and control group (CON, n =12. The SJG performed only single jumps, the RJG executed repeated (consecutive jumps, whereas the CON did not perform any exercises at all. A countermovement jump (CMJ, repeated countermovement jumps (RCMJ, and a drop jump (DJ were tested before and after the training. Only the RJG showed a significantly reduced VGRF (p<0.05 in all tests. Both plyometric groups significantly improved (p<0.05 their jump height in all tests. The LT was significantly greater in the RJG, compared to the SJG, in all tests. The KF was also significantly (p<0.05 greater in the RJG than in the SJG for CMJ and RCMJ. The results suggest that repeated jumps are beneficial for simultaneous landing force reduction and jumping performance enhancement.

  9. Reversal of haloperidol induced motor deficits in rats exposed to repeated immobilization stress.

    Science.gov (United States)

    Shireen, Erum; Pervez, Sidra; Masroor, Maria; Ali, Wafa Binte; Rais, Qudsia; Khalil, Samira; Tariq, Anum; Haleem, Darakshan Jabeen

    2014-09-01

    Stress is defined as a non specific response of body to any physiological and psychological demand. Preclinical studies have shown that an uncontrollable stress condition produces neurochemical and behavioral deficits. The present study was conducted to test the hypothesis that a decrease in the responsiveness of somatodendritic 5-hydroxytryptamine (5-HT)-1A receptors following adaptation to stress could attenuate haloperidol induced acute parkinsonian like effect. Results showed that single exposure (2h) to immobilization stress markedly decreased food intake, growth rate and locomotor activity but these stress-induced behavioral deficits were not observed following repeated (2h/day for 5 days) exposure of immobilization stress suggesting behavioral tolerance occurs to similar stress. An important finding of present study is a reversal of haloperidol-induced motor deficits in animals exposed to repeated immobilization stress than respective control animals. It is suggested that stress induced possible desensitization of somatodendritic 5-HT-1A as well as 5-HT-2C receptors could release dopamine system from the inhibitory influence of serotonin. On the other hand, an increase in the effectiveness of postsynaptic 5-HT-1A receptors elicits a direct stimulatory influence on the activity of dopaminergic neuron and is possibly involved in the reversal of haloperidol-induced parkinsonian like symptoms in repeatedly immobilized rats.

  10. Coordination in continuously repeated games

    NARCIS (Netherlands)

    Weeren, A.J.T.M.; Schumacher, J.M.; Engwerda, J.C.

    1995-01-01

    In this paper we propose a model to describe the effectiveness of coordination in a continuously repeated two-player game. We study how the choice of a decision rule by a coordinator affects the strategic behavior of the players, resulting in more or less cooperation. Our model requires the analysis

  11. A large complement of the predicted Arabidopsis ARM repeat proteins are members of the U-box E3 ubiquitin ligase family.

    Science.gov (United States)

    Mudgil, Yashwanti; Shiu, Shin-Han; Stone, Sophia L; Salt, Jennifer N; Goring, Daphne R

    2004-01-01

    The Arabidopsis genome was searched to identify predicted proteins containing armadillo (ARM) repeats, a motif known to mediate protein-protein interactions in a number of different animal proteins. Using domain database predictions and models generated in this study, 108 Arabidopsis proteins were identified that contained a minimum of two ARM repeats with the majority of proteins containing four to eight ARM repeats. Clustering analysis showed that the 108 predicted Arabidopsis ARM repeat proteins could be divided into multiple groups with wide differences in their domain compositions and organizations. Interestingly, 41 of the 108 Arabidopsis ARM repeat proteins contained a U-box, a motif present in a family of E3 ligases, and these proteins represented the largest class of Arabidopsis ARM repeat proteins. In 14 of these U-box/ARM repeat proteins, there was also a novel conserved domain identified in the N-terminal region. Based on the phylogenetic tree, representative U-box/ARM repeat proteins were selected for further study. RNA-blot analyses revealed that these U-box/ARM proteins are expressed in a variety of tissues in Arabidopsis. In addition, the selected U-box/ARM proteins were found to be functional E3 ubiquitin ligases. Thus, these U-box/ARM proteins represent a new family of E3 ligases in Arabidopsis.

  12. In silico analysis of Simple Sequence Repeats from chloroplast genomes of Solanaceae species

    Directory of Open Access Journals (Sweden)

    Evandro Vagner Tambarussi

    2009-01-01

    Full Text Available The availability of chloroplast genome (cpDNA sequences of Atropa belladonna, Nicotiana sylvestris, N.tabacum, N. tomentosiformis, Solanum bulbocastanum, S. lycopersicum and S. tuberosum, which are Solanaceae species,allowed us to analyze the organization of cpSSRs in their genic and intergenic regions. In general, the number of cpSSRs incpDNA ranged from 161 in S. tuberosum to 226 in N. tabacum, and the number of intergenic cpSSRs was higher than geniccpSSRs. The mononucleotide repeats were the most frequent in studied species, but we also identified di-, tri-, tetra-, pentaandhexanucleotide repeats. Multiple alignments of all cpSSRs sequences from Solanaceae species made the identification ofnucleotide variability possible and the phylogeny was estimated by maximum parsimony. Our study showed that the plastomedatabase can be exploited for phylogenetic analysis and biotechnological approaches.

  13. Opposite patterns of change in perception of imagined and physically induced pain over the course of repeated thermal stimulations.

    Science.gov (United States)

    Gács, B; Szolcsányi, T; Csathó, Á

    2017-08-01

    Individuals frequently show habituation to repeated noxious heat. However, given the defensive function of human pain processing, it is reasonable to assume that individuals anticipate that they would become increasingly sensitive to repeated thermal pain stimuli. No previous studies have, however, been addressed to this assumption. Therefore, in the current study, we investigated how healthy human individuals imagine the intensity of repeated thermal pain stimulations, and compared this with the intensity ratings given after physically induced thermal pain trials. Healthy participants (N = 20) gave pain intensity ratings in two conditions: imagined and real thermal pain. In the real pain condition, thermal pain stimuli of two intensities (minimal and moderate pain) were delivered in four consecutive trials. The duration of the peak temperature was 20 s, and stimulation was always delivered to the same location. In each trial, participants rated the pain intensity twice, 5 and 15 s after the onset of the peak temperature. In the imagined pain condition, participants were subjected to a reference pain stimulus and then asked to imagine and rate the same sequence of stimulations as in the induced pain condition. Ratings of imagined pain and physically induced pain followed opposite courses over repeated stimulations: Ratings of imagined pain indicated sensitization, whereas ratings for physically induced pain indicated habituation. The findings were similar for minimal and moderate pain intensities. The findings suggest that, rather than habituating to pain, healthy individuals imagine that they would become increasingly sensitive to repeated thermal pain stimuli. This study identified opposite patterns of change in perception of imagined pain (sensitization) and physically induced pain (habituation). The findings show that individuals anticipate that they would become increasingly sensitive to repeated pain stimuli, which might also have clinical implications.

  14. Analysis of repeated measures data

    CERN Document Server

    Islam, M Ataharul

    2017-01-01

    This book presents a broad range of statistical techniques to address emerging needs in the field of repeated measures. It also provides a comprehensive overview of extensions of generalized linear models for the bivariate exponential family of distributions, which represent a new development in analysing repeated measures data. The demand for statistical models for correlated outcomes has grown rapidly recently, mainly due to presence of two types of underlying associations: associations between outcomes, and associations between explanatory variables and outcomes. The book systematically addresses key problems arising in the modelling of repeated measures data, bearing in mind those factors that play a major role in estimating the underlying relationships between covariates and outcome variables for correlated outcome data. In addition, it presents new approaches to addressing current challenges in the field of repeated measures and models based on conditional and joint probabilities. Markov models of first...

  15. Prognostic usefulness of repeated echocardiographic evaluation after acute myocardial infarction. TRACE Study Group. TRAndolapril Cardiac Evaluation

    DEFF Research Database (Denmark)

    Korup, E; Køber, L; Torp-Pedersen, C

    1999-01-01

    The prognostic value of repeated echocardiographic measurement of left ventricular function after acute myocardial infarction was evaluated. We found that repeated measurements of wall motion index in survivors of acute myocardial infarction, with no reinfarction, provide important prognostic...

  16. Collaborative work on evaluation of ovarian toxicity. 13) Two- or four-week repeated dose studies and fertility study of PPAR alpha/gamma dual agonist in female rats.

    Science.gov (United States)

    Sato, Norihiro; Uchida, Keisuke; Nakajima, Mikio; Watanabe, Atsushi; Kohira, Terutomo

    2009-01-01

    The main focus of this study was to determine the optimal dosing period in a repeated dose toxicity study based on toxic effects as assessed by ovarian morphological changes. To assess morphological and functional changes induced in the ovary by a peroxisome proliferator-activated receptor (PPAR) alpha/gamma dual agonist, the compound was administered to female rats at dose levels of 0, 4, 20, and 100 mg/kg/day in a repeated dose toxicity study for 2 or 4 weeks, and from 2 weeks prior to mating to Day 7 of pregnancy in a female fertility study. In the repeated dose toxicity study, an increase in atresia of large follicles, a decrease in corpora lutea, and an increase in stromal cells were observed in the treated groups. In addition, the granulosa cell exfoliations into antrum of large follicles and corpora lutea with retained oocyte are morphological characteristics induced by this compound, and they might be related with abnormal condition of ovulation. In the female fertility study, the pregnancy rate tended to decrease in the 100 mg/kg/day group. At necropsy, decreases in the number of corpora lutea, implantations and live embryos were noted in the 20 and 100 mg/kg/day group. No changes were observed in animals given 4 mg/kg/day. These findings indicated that histopathological changes in the ovary are important endpoints for evaluation of drugs inducing ovarian damage. In conclusion, a 2-week administration period is sufficient to detect ovarian toxicity of this test compound in the repeated dose toxicity study.

  17. Second-Grade Urban Learners: Preliminary Findings for a Computer-Assisted, Culturally Relevant, Repeated Reading Intervention

    Science.gov (United States)

    Bennett, Jessica G.; Gardner, Ralph, III; Cartledge, Gwendolyn; Ramnath, Rajiv; Council, Morris R., III

    2017-01-01

    This study investigated the effects of a multicomponent, supplemental intervention on the reading fluency of second-grade African-American urban students who showed reading and special education risk. The packaged intervention combined repeated readings and culturally relevant stories, delivered through a novel computer software program to enhance…

  18. The relationship of social support concept and repeat mammography among Iranian women.

    Science.gov (United States)

    Farhadifar, Fariba; Taymoori, Parvaneh; Bahrami, Mitra; Zarea, Shamsy

    2015-10-24

    Breast cancer ranks as the first most common cancer among the Iranian women. The regular repeat of mammography with 1-2 year intervals leads to the increased efficiency of early detection of breast cancer. The present study examined the predictors of repeat mammography. It was hypothesized that higher social support is connected with mammography repeat. A cross-sectional study was carried out among 400 women 50 years and older in Sanandaj, Iran. Data was collected by the questionnaire including information on socio demographical variables and measuring social support level. Data was analyzed by SPSS16 software. Multiple logistic regression was used to determine the predictive power of demographic variables and dimensions of social support for repeat mammography. Women aged 50-55 years had three times odds of repeat mammography compared to women aged 56-60 years) OR, 3.02). Married women had greater odds of repeat mammography compared to single women (P women with higher social support was 0.93 times greater than the women with lower social support (OR, 0.93; 95 % CI, 0.91-0.95; P women are less likely repeat mammography than other Asian women. Identifying the associations between perceived social support and repeat mammography may offer detailed information to allow for future study and guide the development of interventions not only for Iranian women but also for similar cultural that received pay too little attention to date in the breast cancer literature.

  19. Visual assessment of the cervical vertebral maturation stages: A study of diagnostic accuracy and repeatability.

    Science.gov (United States)

    Perinetti, Giuseppe; Caprioglio, Alberto; Contardo, Luca

    2014-11-01

    To evaluate the diagnostic accuracy and repeatability of the visual assessment of the cervical vertebral maturation (CVM) stages. Ten operators underwent training sessions in visual assessment of CVM staging. Subsequently, they were asked to stage 72 cases equally divided into the six stages. Such assessment was repeated twice in two sessions (T1 and T2) 4 weeks apart. A reference standard for each case was created according to a cephalometric analysis of both the concavities and shapes of the cervical vertebrae. The overall agreement with the reference standard was about 68% for both sessions and 76.9% for intrarater repeatability. The overall kappa coefficients with the reference standard were up to 0.86 for both sessions, and 0.88 for intrarater repeatability. Overall, disagreements one stage and twp stage apart were 23.5% (T1) and 5.1% (T2), respectively. Sensitivity ranged from 53.3% for CS5 (T1) to 99.9% for CS1 (T2), positive predictive values ranged from 52.4% for CS5 (T2) to 94.3% for CS6 (T1), and accuracy ranged from 83.6% for CS4 (T2) to 94.9% for CS1 (T1). Visual assessment of the CVM stages is accurate and repeatable to a satisfactory level. About one in three cases remain misclassified; disagreement is generally limited to one stage and is mostly seen in stages 4 and 5.

  20. A high stability and repeatability electrochemical scanning tunneling microscope

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Zhigang; Wang, Jihao; Lu, Qingyou, E-mail: qxl@ustc.edu.cn [High Magnetic Field Laboratory, Chinese Academy of Sciences and University of Science and Technology of China, Hefei, Anhui 230026 (China); Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026 (China); Hou, Yubin [High Magnetic Field Laboratory, Chinese Academy of Sciences and University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2014-12-15

    We present a home built electrochemical scanning tunneling microscope (ECSTM) with very high stability and repeatability. Its coarse approach is driven by a closely stacked piezo motor of GeckoDrive type with four rigid clamping points, which enhances the rigidity, compactness, and stability greatly. It can give high clarity atomic resolution images without sound and vibration isolations. Its drifting rates in XY and Z directions in solution are as low as 84 pm/min and 59 pm/min, respectively. In addition, repeatable coarse approaches in solution within 2 mm travel distance show a lateral deviation less than 50 nm. The gas environment can be well controlled to lower the evaporation rate of the cell, thus reducing the contamination and elongating the measurement time. Atomically resolved SO{sub 4}{sup 2−} image on Au (111) work electrode is demonstrated to show the performance of the ECSTM.

  1. A comparative study on pathological features of transgenic rat lines expressing either three or four repeat misfolded tau.

    Science.gov (United States)

    Valachova, Bernadeta; Brezovakova, Veronika; Bugos, Ondrej; Jadhav, Santosh; Smolek, Tomas; Novak, Petr; Zilka, Norbert

    2018-08-01

    Human tauopathies represent a heterogeneous group of neurodegenerative disorders characterized by distinct clinical features, typical histopathological structures, and defined ratio(s) of three-repeat and four-repeat tau isoforms within pathological aggregates. How the optional microtubule-binding repeat of tau influences this differentiation of pathologies is understudied. We have previously generated and characterized transgenic rodent models expressing human truncated tau aa151-391 with either three (SHR24) or four microtubule-binding repeats (SHR72). Here, we compare the behavioral and neuropathological hallmarks of these two transgenic lines using a battery of tests for sensorimotor, cognitive, and neurological functions over the age range of 3.5-15 months. Progression of sensorimotor and neurological deficits was similar in both transgenic lines; however, the lifespan of transgenic line SHR72 expressing truncated four-repeat tau was markedly shorter than SHR24. Moreover, the expression of three or four-repeat tau induced distinct neurofibrillary pathology in these lines. Transgenic lines displayed different distribution of tau pathology and different type of neurofibrillary tangles. Our results suggest that three- and four-repeat isoforms of tau may display different modes of action in the diseased brain. © 2018 Wiley Periodicals, Inc.

  2. Intraspecific variation in flight metabolic rate in the bumblebee Bombus impatiens: repeatability and functional determinants in workers and drones.

    Science.gov (United States)

    Darveau, Charles-A; Billardon, Fannie; Bélanger, Kasandra

    2014-02-15

    The evolution of flight energetics requires that phenotypes be variable, repeatable and heritable. We studied intraspecific variation in flight energetics in order to assess the repeatability of flight metabolic rate and wingbeat frequency, as well as the functional basis of phenotypic variation in workers and drones of the bumblebee species Bombus impatiens. We showed that flight metabolic rate and wingbeat frequency were highly repeatable in workers, even when controlling for body mass variation using residual analysis. We did not detect significant repeatability in drones, but a smaller range of variation might have prevented us from finding significant values in our sample. Based on our results and previous findings, we associated the high repeatability of flight phenotypes in workers to the functional links between body mass, thorax mass, wing size, wingbeat frequency and metabolic rate. Moreover, differences between workers and drones were as predicted from these functional associations, where drones had larger wings for their size, lower wingbeat frequency and lower flight metabolic rate. We also investigated thoracic muscle metabolic phenotypes by measuring the activity of carbohydrate metabolism enzymes, and we found positive correlations between mass-independent metabolic rate and the activity of all enzymes measured, but in workers only. When comparing workers and drones that differ in flight metabolic rate, only the activity of the enzymes hexokinase and trehalase showed the predicted differences. Overall, our study indicates that there should be correlated evolution among physiological phenotypes at multiple levels of organization and morphological traits associated with flight.

  3. Electromyographic analysis of repeated bouts of eccentric exercise.

    Science.gov (United States)

    McHugh, M P; Connolly, D A; Eston, R G; Gartman, E J; Gleim, G W

    2001-03-01

    The repeated bout effect refers to the protective effect provided by a single bout of eccentric exercise against muscle damage from a similar subsequent bout. The aim of this study was to determine if the repeated bout was associated with an increase in motor unit activation relative to force production, an increased recruitment of slow-twitch motor units or increased motor unit synchronization. Surface electromyographic (EMG) signals were recorded from the hamstring muscles during two bouts of submaximal isokinetic (2.6 rad x s(-1)) eccentric (11 men, 9 women) or concentric (6 men, 4 women) contractions separated by 2 weeks. The EMG per unit torque and median frequency were analysed. The initial bout of eccentric exercise resulted in strength loss, pain and muscle tenderness, while the repeated eccentric bout resulted in a slight increase in strength, no pain and no muscle tenderness (bout x time effects, P exercise. The EMG per unit torque and median frequency were not different between the initial and repeated bouts of eccentric exercise. The EMG per unit torque and median frequency increased during both bouts of eccentric exercise (P < 0.01) but did not change during either concentric bout. In conclusion, there was no evidence that the repeated bout effect was due to a neural adaptation.

  4. Repeated radiation injuries by fission products

    International Nuclear Information System (INIS)

    Vasilenko, I.Ya.

    1986-01-01

    Attention is given to repeated radiation injuries during internal irradiation of theoretical and practical interest, particularly in case of the intake into organism of young products of nuclear fission (PNF). The results of experiments with dogs with repeated radioactive iodine injury the isotopes of which (131-135sub(I)) constitute a considerable part of PNF activity are discussed. The blood reaction and protein metabolism state have been studied. Observations for dogs have been continued for about 4 years. The doses for thyroid, gastrointestinal tract and liver subjected to the most intensive irradiation consituted in the first series of experiments after the first intake about 3;0.3;0.05 Gy, after the second - 5;0.5;0.08 Gy and in the second series of experiments - 3;0.3;0.05 Gy and 0.6;0.06;0.01 Gy, respectively. Hematologic factors,thyroid function, changes in exchange and immunologic reactivity have been studied. The dogs have been under observation for 5 years. It is shown in case of repeated intake of Isup(131) PNF into animals organism in quantity which does not cause during the acute period a clinically outlined sickness, substantial differences in the organism reaction as compared with the first intake of radionuclides have not been found. The presence of residual radiation injuries did not cause charging action during the acute period during PNF and repeated intake which in the author's opinion testifies to perfection of compensator mechanisms in case of intake of such quantities of radioactive products. At the remote periods blastomogenic action manifested which is estimated as a result of general biological action of radionuclides administered to the organism. The necessity in subsequent investigations for obtaining the data on organism reactivity, clinic and pathogenesis with the aim of prophylaxis and treatment of such injuries is indicated

  5. Use of short tandem repeat sequences to study Mycobacterium leprae in leprosy patients in Malawi and India.

    Directory of Open Access Journals (Sweden)

    Saroj K Young

    2008-04-01

    Full Text Available Inadequate understanding of the transmission of Mycobacterium leprae makes it difficult to predict the impact of leprosy control interventions. Genotypic tests that allow tracking of individual bacterial strains would strengthen epidemiological studies and contribute to our understanding of the disease.Genotyping assays based on variation in the copy number of short tandem repeat sequences were applied to biopsies collected in population-based epidemiological studies of leprosy in northern Malawi, and from members of multi-case households in Hyderabad, India. In the Malawi series, considerable genotypic variability was observed between patients, and also within patients, when isolates were collected at different times or from different tissues. Less within-patient variability was observed when isolates were collected from similar tissues at the same time. Less genotypic variability was noted amongst the closely related Indian patients than in the Malawi series.Lineages of M. leprae undergo changes in their pattern of short tandem repeat sequences over time. Genetic divergence is particularly likely between bacilli inhabiting different (e.g., skin and nerve tissues. Such variability makes short tandem repeat sequences unsuitable as a general tool for population-based strain typing of M. leprae, or for distinguishing relapse from reinfection. Careful use of these markers may provide insights into the development of disease within individuals and for tracking of short transmission chains.

  6. Evaluation of the repeated-dose liver and gastrointestinal tract micronucleus assays with 22 chemicals using young adult rats: summary of the collaborative study by the Collaborative Study Group for the Micronucleus Test (CSGMT)/The Japanese Environmental Mutagen Society (JEMS) - Mammalian Mutagenicity Study Group (MMS).

    Science.gov (United States)

    Hamada, Shuichi; Ohyama, Wakako; Takashima, Rie; Shimada, Keisuke; Matsumoto, Kazumi; Kawakami, Satoru; Uno, Fuyumi; Sui, Hajime; Shimada, Yasushi; Imamura, Tadashi; Matsumura, Shoji; Sanada, Hisakazu; Inoue, Kenji; Muto, Shigeharu; Ogawa, Izumi; Hayashi, Aya; Takayanagi, Tomomi; Ogiwara, Yosuke; Maeda, Akihisa; Okada, Emiko; Terashima, Yukari; Takasawa, Hironao; Narumi, Kazunori; Wako, Yumi; Kawasako, Kazufumi; Sano, Masaki; Ohashi, Nobuyuki; Morita, Takeshi; Kojima, Hajime; Honma, Masamitsu; Hayashi, Makoto

    2015-03-01

    The repeated-dose liver micronucleus (RDLMN) assay using young adult rats has the potential to detect hepatocarcinogens. We conducted a collaborative study to assess the performance of this assay and to evaluate the possibility of integrating it into general toxicological studies. Twenty-four testing laboratories belonging to the Mammalian Mutagenicity Study Group, a subgroup of the Japanese Environmental Mutagen Society, participated in this trial. Twenty-two model chemicals, including some hepatocarcinogens, were tested in 14- and/or 28-day RDLMN assays. As a result, 14 out of the 16 hepatocarcinogens were positive, including 9 genotoxic hepatocarcinogens, which were reported negative in the bone marrow/peripheral blood micronucleus (MN) assay by a single treatment. These outcomes show the high sensitivity of the RDLMN assay to hepatocarcinogens. Regarding the specificity, 4 out of the 6 non-liver targeted genotoxic carcinogens gave negative responses. This shows the high organ specificity of the RDLMN assay. In addition to the RDLMN assay, we simultaneously conducted gastrointestinal tract MN assays using 6 of the above carcinogens as an optional trial of the collaborative study. The MN assay using the glandular stomach, which is the first contact site of the test chemical when administered by oral gavage, was able to detect chromosomal aberrations with 3 test chemicals including a stomach-targeted carcinogen. The treatment regime was the 14- and/or 28-day repeated-dose, and the regime is sufficiently promising to incorporate these methods into repeated-dose toxicological studies. The outcomes of our collaborative study indicated that the new techniques to detect chromosomal aberrations in vivo in several tissues worked successfully. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Concerted evolution of the tandemly repeated genes encoding primate U2 small nuclear RNA (the RNU2 locus) does not prevent rapid diversification of the (CT){sub n} {center_dot} (GA){sub n} microsatellite embedded within the U2 repeat unit

    Energy Technology Data Exchange (ETDEWEB)

    Liao, D.; Weiner, A.M. [Yale Univ., New Haven, CT (United States)

    1995-12-10

    The RNU2 locus encoding human U2 small nuclear RNA (snRNA) is organized as a nearly perfect tandem array containing 5 to 22 copies of a 5.8-kb repeat unit. Just downstream of the U2 snRNA gene in each 5.8-kb repeat unit lies a large (CT){sub n}{center_dot}(GA){sub n} dinucleotide repeat (n {approx} 70). This form of genomic organization, in which one repeat is embedded within another, provides an unusual opportunity to study the balance of forces maintaining the homogeneity of both kinds of repeats. Using a combination of field inversion gel electrophoresis and polymerase chain reaction, we have been able to study the CT microsatellites within individual U2 tandem arrays. We find that the CT microsatellites within an RNU2 allele exhibit significant length polymorphism, despite the remarkable homogeneity of the surrounding U2 repeat units. Length polymorphism is due primarily to loss or gain of CT dinucleotide repeats, but other types of deletions, insertions, and substitutions are also frequent. Polymorphism is greatly reduced in regions where pure (CT){sub n} tracts are interrupted by occasional G residues, suggesting that irregularities stabilize both the length and the sequence of the dinucleotide repeat. We further show that the RNU2 loci of other catarrhine primates (gorilla, chimpanzee, ogangutan, and baboon) contain orthologous CT microsatellites; these also exhibit length polymorphism, but are highly divergent from each other. Thus, although the CT microsatellite is evolving far more rapidly than the rest of the U2 repeat unit, it has persisted through multiple speciation events spanning >35 Myr. The persistence of the CT microsatellite, despite polymorphism and rapid evolution, suggests that it might play a functional role in concerted evolution of the RNU2 loci, perhaps as an initiation site for recombination and/or gene conversion. 70 refs., 5 figs.

  8. Repeated nicotine exposure enhances reward-related learning in the rat.

    Science.gov (United States)

    Olausson, Peter; Jentsch, J David; Taylor, Jane R

    2003-07-01

    Repeated exposure to addictive drugs causes neuroadaptive changes in cortico-limbic-striatal circuits that may underlie alterations in incentive-motivational processes and reward-related learning. Such drug-induced alterations may be relevant to drug addiction because enhanced incentive motivation and increased control over behavior by drug-associated stimuli may contribute to aspects of compulsive drug-seeking and drug-taking behaviors. This study investigated the consequences of repeated nicotine treatment on the acquisition and performance of Pavlovian discriminative approach behavior, a measure of reward-related learning, in male rats. Water-restricted rats were trained to associate a compound conditioned stimulus (tone+light) with the availability of water (the unconditioned stimulus) in 15 consecutive daily sessions. In separate experiments, rats were repeatedly treated with nicotine (0.35 mg/kg, s.c.) either (1) prior to the onset of training, (2) after each daily training session was completed (ie postsession injections), or (3) received nicotine both before the onset of training as well as after each daily training session. In this study, all nicotine treatment schedules increased Pavlovian discriminative approach behavior and, thus, prior repeated exposure to nicotine, repeated postsession nicotine injections, or both, facilitated reward-related learning.

  9. Alanine repeats influence protein localization in splicing speckles and paraspeckles.

    Science.gov (United States)

    Chang, Shuo-Hsiu; Chang, Wei-Lun; Lu, Chia-Chen; Tarn, Woan-Yuh

    2014-12-16

    Mammalian splicing regulatory protein RNA-binding motif protein 4 (RBM4) has an alanine repeat-containing C-terminal domain (CAD) that confers both nuclear- and splicing speckle-targeting activities. Alanine-repeat expansion has pathological potential. Here we show that the alanine-repeat tracts influence the subnuclear targeting properties of the RBM4 CAD in cultured human cells. Notably, truncation of the alanine tracts redistributed a portion of RBM4 to paraspeckles. The alanine-deficient CAD was sufficient for paraspeckle targeting. On the other hand, alanine-repeat expansion reduced the mobility of RBM4 and impaired its splicing activity. We further took advantage of the putative coactivator activator (CoAA)-RBM4 conjoined splicing factor, CoAZ, to investigate the function of the CAD in subnuclear targeting. Transiently expressed CoAZ formed discrete nuclear foci that emerged and subsequently separated-fully or partially-from paraspeckles. Alanine-repeat expansion appeared to prevent CoAZ separation from paraspeckles, resulting in their complete colocalization. CoAZ foci were dynamic but, unlike paraspeckles, were resistant to RNase treatment. Our results indicate that the alanine-rich CAD, in conjunction with its conjoined RNA-binding domain(s), differentially influences the subnuclear localization and biogenesis of RBM4 and CoAZ. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  10. Neonates’ responses to repeated exposure to a still face

    Science.gov (United States)

    Pilling, Karen; Watt, Rachel; Pal, Attila; Orvos, Hajnalka

    2017-01-01

    Aim The main aims of the study were to examine whether human neonates’ responses to communication disturbance modelled by the still-face paradigm were stable and whether their responses were affected by their previous experience with the still-face paradigm. Methods The still face procedure, as a laboratory model of interpersonal stress, was administered repeatedly, twice, to 84 neonates (0 to 4 day olds), with a delay of an average of 1.25 day. Results Frame-by-frame analysis of the frequency and duration of gaze, distressed face, crying, sleeping and sucking behaviours showed that the procedure was stressful to them both times, that is, the still face effect was stable after repeated administration and newborns consistently responded to such nonverbal violation of communication. They averted their gaze, showed distress and cried more during the still-face phase in both the first and the second administration. They also showed a carry-over effect in that they continued to avert their gaze and displayed increased distress and crying in the first reunion period, but their gaze behaviour changed with experience, in the second administration. While in the first administration the babies continued averting their gaze even after the stressful still-face phase was over, this carry-over effect disappeared in the second administration, and the babies significantly increased their gaze following the still-face phase. Conclusion After excluding explanations of fatigue, habituation and random effects, a self-other regulatory model is discussed as a possible explanation for this pattern. PMID:28771555

  11. Repeated restraint stress exposure during early withdrawal accelerates incubation of cue-induced cocaine craving.

    Science.gov (United States)

    Glynn, Ryan M; Rosenkranz, J Amiel; Wolf, Marina E; Caccamise, Aaron; Shroff, Freya; Smith, Alyssa B; Loweth, Jessica A

    2018-01-01

    A major challenge for treating cocaine addiction is the propensity for abstinent users to relapse. Two important triggers for relapse are cues associated with prior drug use and stressful life events. To study their interaction in promoting relapse during abstinence, we used the incubation model of craving and relapse in which cue-induced drug seeking progressively intensifies ('incubates') during withdrawal from extended-access cocaine self-administration. We tested rats for cue-induced cocaine seeking on withdrawal day (WD) 1. Rats were then subjected to repeated restraint stress or control conditions (seven sessions held between WD6 and WD14). All rats were tested again for cue-induced cocaine seeking on WD15, 1 day after the last stress or control session. Although controls showed a time-dependent increase in cue-induced cocaine seeking (incubation), rats exposed to repeated stress in early withdrawal exhibited a more robust increase in seeking behavior between WD1 and WD15. In separate stressed and control rats, equivalent cocaine seeking was observed on WD48. These results indicate that repeated stress in early withdrawal accelerates incubation of cocaine craving, although craving plateaus at the same level were observed in controls. However, 1 month after the WD48 test, rats subjected to repeated stress in early withdrawal showed enhanced cue-induced cocaine seeking following acute (24 hours) food deprivation stress. Together, these data indicate that chronic stress exposure enhances the initial rate of incubation of craving during early withdrawal, resulting in increased vulnerability to cue-induced relapse during this period, and may lead to a persistent increase in vulnerability to the relapse-promoting effects of stress. © 2016 Society for the Study of Addiction.

  12. Use of repeat anterior maxillary distraction to correct residual midface hypoplasia in cleft patients.

    Science.gov (United States)

    Richardson, Sunil; Krishna, Shreya; Bansal, Avi

    2017-12-01

    The study was designed to evaluate the efficacy of performing a second, repeat anterior maxillary distraction (AMD) to treat residual cleft maxillary hypoplasia. Five patients between the ages of 12 to 15 years with a history of AMD and with residual cleft maxillary hypoplasia were included in the study. Inclusion was irrespective of gender, type of cleft lip and palate, and the amount of advancement needed. Repeat AMD was executed in these patients 4 to 5 years after the primary AMD procedure to correct the cleft maxillary hypoplasia that had developed since the initial procedure. Orthopantomogram (OPG) and lateral cephalograms were taken for evaluation preoperatively, immediately after distraction, after consolidation, and one year postoperatively. The data obtained was tabulated and a Mann Whitney U-test was used for statistical comparisons. At the time of presentation, a residual maxillary hypoplasia was observed with a well maintained distraction gap on the OPG which ruled out the occurrence of a relapse. Favorable movement of the segments without any resistance was seen in all patients. Mean maxillary advancement of 10.56 mm was achieved at repeat AMD. Statistically significant increases in midfacial length, SNA angle, and nasion perpendicular to point A distance was achieved ( P =0.012, P =0.011, and P =0.012, respectively). Good profile was achieved for all patients. Minimal transient complications, for example anterior open bite and bleeding episodes, were managed. Addressing the problem of cleft maxillary hypoplasia at an early age (12-15 years) is beneficial for the child. Residual hypoplasia may develop in some patients, which may require additional corrective procedures. The results of our study show that AMD can be repeated when residual deformity develops with the previous procedure having no negative impact on the results of the repeat procedure.

  13. Determinants of repeated abortion among women of reproductive age attending health facilities in Northern Ethiopia: a case–control study

    Directory of Open Access Journals (Sweden)

    Mussie Alemayehu

    2017-02-01

    Full Text Available Abstract Background Every year, an estimated 19–20 million unsafe abortions take place, almost all in developing countries, leading to 68,000 deaths and millions more injured many permanently. Many women throughout the world, experience more than one abortion in their lifetimes. Repeat abortion is an indicator of the larger problem of unintended pregnancy. This study aimed to identify determinants of repeat abortion in Tigray Region, Ethiopia. Methods Unmatched case–control study was conducted in hospitals in Tigray Region, northern Ethiopia, from November 2014 to June 2015. The sample included 105 cases and 204 controls, recruited from among women seeking abortion care at public hospitals. Clients having two or more abortions (“repeat abortion” were taken as cases and those who had a total of one abortion were taken as controls (“single abortion”. Cases were selected consecutive based on proportional to size allocation while systematic sampling was employed for controls. Data were analyzed using SPSS version 20.0. Binary and multiple variable logistic regression analyses were calculated with 95% CI. Results Mean age of cases was 24 years (±6.85 and 22 years (±6.25 for controls. 79.0% of cases had their sexual debut in less than 18 years of age compared to 57% of controls. 42.2% of controls and 23.8% of cases cited rape as the reason for having an abortion. Study participants who did not understand their fertility cycle and when they were most likely to conceive after menstruation (adjusted odds ratio [AOR] = 2.0, 95% confidence interval [CI]: 1.1–3.7, having a previous abortion using medication (AOR = 3.3, CI: 1.83, 6.11, having multiple sexual partners in the preceding 12 months (AOR = 4.4, CI: 2.39,8.45, perceiving that the abortion procedure is not painful (AOR = 2.3, CI: 1.31,4.26, initiating sexual intercourse before the age of 18 years (AOR = 2.7, CI: 1.49, 5.23 and disclosure to a third

  14. Personal semantics: Is it distinct from episodic and semantic memory? An electrophysiological study of memory for autobiographical facts and repeated events in honor of Shlomo Bentin.

    Science.gov (United States)

    Renoult, Louis; Tanguay, Annick; Beaudry, Myriam; Tavakoli, Paniz; Rabipour, Sheida; Campbell, Kenneth; Moscovitch, Morris; Levine, Brian; Davidson, Patrick S R

    2016-03-01

    Declarative memory is thought to consist of two independent systems: episodic and semantic. Episodic memory represents personal and contextually unique events, while semantic memory represents culturally-shared, acontextual factual knowledge. Personal semantics refers to aspects of declarative memory that appear to fall somewhere in between the extremes of episodic and semantic. Examples include autobiographical knowledge and memories of repeated personal events. These two aspects of personal semantics have been studied little and rarely compared to both semantic and episodic memory. We recorded the event-related potentials (ERPs) of 27 healthy participants while they verified the veracity of sentences probing four types of questions: general (i.e., semantic) facts, autobiographical facts, repeated events, and unique (i.e., episodic) events. Behavioral results showed equivalent reaction times in all 4 conditions. True sentences were verified faster than false sentences, except for unique events for which no significant difference was observed. Electrophysiological results showed that the N400 (which is classically associated with retrieval from semantic memory) was maximal for general facts and the LPC (which is classically associated with retrieval from episodic memory) was maximal for unique events. For both ERP components, the two personal semantic conditions (i.e., autobiographical facts and repeated events) systematically differed from semantic memory. In addition, N400 amplitudes also differentiated autobiographical facts from unique events. Autobiographical facts and repeated events did not differ significantly from each other but their corresponding scalp distributions differed from those associated with general facts. Our results suggest that the neural correlates of personal semantics can be distinguished from those of semantic and episodic memory, and may provide clues as to how unique events are transformed to semantic memory. Copyright © 2015 Elsevier

  15. Repeated checking induces uncertainty about future threat

    NARCIS (Netherlands)

    Giele, C.L.|info:eu-repo/dai/nl/318754460; Engelhard, I.M.|info:eu-repo/dai/nl/239681533; van den Hout, M.A.|info:eu-repo/dai/nl/070445354; Dek, E.C.P.|info:eu-repo/dai/nl/313959552; Damstra, Marianne; Douma, Ellen

    2015-01-01

    Studies have shown that obsessive-compulsive (OC) -like repeated checking paradoxically increases memory uncertainty. This study tested if checking also induces uncertainty about future threat by impairing the distinction between danger and safety cues. Participants (n = 54) engaged in a simulated

  16. Repeatability and Reproducibility of Fibre-Based Nanogenerator Synthesized by Electrospinning Machine

    International Nuclear Information System (INIS)

    Suyitno; Huda, Sholiehul; Arifin, Zainal; Hadi, Syamsul; Lambang, Raymundus Lullus

    2014-01-01

    Zinc oxide fibres-based nanogenerators synthesized easily by electrospinning machine are promising to harvest electricity from mechanical energy. However, the repeatability and reproducibility were two major factors needed to be investigated to minimize product failure and to determine the feasibility of mass production of nanogenerators. The green fibres of zinc oxide were produced by electrospinning machine of zinc acetate and polyvinyl alcohol solution at a flow rate of 4 μL/min followed by sintering at temperature 550°C with heating rate 240°C/h. Each 10 nanogenerators was tested by three trained operators with three times of repetition at compressive load 0.5 kg. The nanogenerators revealed the maximum output voltage ranging from 203 to 217 mV. The value of repeatability and reproducibility of nanogenerators was approximately 24.29% showing that nanogenerators were still acceptable to be mass-produced. The relatively low reproducibility was mainly due to the operators, so that the checklist needed to be made easier and simpler for all the variables affecting to the quality of the fibres. Reducing the value of the repeatability and reproducibility is interesting to study further by creating a rotating collector so that the thickness and orientation of fibres can be arranged better

  17. Unusually effective microRNA targeting within repeat-rich coding regions of mammalian mRNAs

    Science.gov (United States)

    Schnall-Levin, Michael; Rissland, Olivia S.; Johnston, Wendy K.; Perrimon, Norbert; Bartel, David P.; Berger, Bonnie

    2011-01-01

    MicroRNAs (miRNAs) regulate numerous biological processes by base-pairing with target messenger RNAs (mRNAs), primarily through sites in 3′ untranslated regions (UTRs), to direct the repression of these targets. Although miRNAs have sometimes been observed to target genes through sites in open reading frames (ORFs), large-scale studies have shown such targeting to be generally less effective than 3′ UTR targeting. Here, we show that several miRNAs each target significant groups of genes through multiple sites within their coding regions. This ORF targeting, which mediates both predictable and effective repression, arises from highly repeated sequences containing miRNA target sites. We show that such sequence repeats largely arise through evolutionary duplications and occur particularly frequently within families of paralogous C2H2 zinc-finger genes, suggesting the potential for their coordinated regulation. Examples of ORFs targeted by miR-181 include both the well-known tumor suppressor RB1 and RBAK, encoding a C2H2 zinc-finger protein and transcriptional binding partner of RB1. Our results indicate a function for repeat-rich coding sequences in mediating post-transcriptional regulation and reveal circumstances in which miRNA-mediated repression through ORF sites can be reliably predicted. PMID:21685129

  18. Impaired intracortical transmission in G2019S leucine rich-repeat kinase Parkinson patients.

    Science.gov (United States)

    Ponzo, Viviana; Di Lorenzo, Francesco; Brusa, Livia; Schirinzi, Tommaso; Battistini, Stefania; Ricci, Claudia; Sambucci, Manolo; Caltagirone, Carlo; Koch, Giacomo

    2017-05-01

    A mutation in leucine-rich repeat kinase 2 is the most common cause of hereditary Parkinson's disease (PD), yet the neural mechanisms and the circuitry potentially involved are poorly understood. We used different transcranial magnetic stimulation protocols to explore in the primary motor cortex the activity of intracortical circuits and cortical plasticity (long-term potentiation) in patients with the G2019S leucine-rich repeat kinase 2 gene mutation when compared with idiopathic PD patients and age-matched healthy subjects. Paired pulse transcranial magnetic stimulation was used to investigate short intracortical inhibition and facilitation and short afferent inhibition. Intermittent theta burst stimulation, a form of repetitive transcranial magnetic stimulation, was used to test long-term potentiation-like cortical plasticity. Leucine-rich repeat kinase 2 and idiopathic PD were tested both in ON and in OFF l-dopa therapy. When compared with idiopathic PD and healthy subjects, leucine-rich repeat kinase 2 PD patients showed a remarkable reduction of short intracortical inhibition in both ON and in OFF l-dopa therapy. This reduction was paralleled by an increase of intracortical facilitation in OFF l-dopa therapy. Leucine-rich repeat kinase 2 PD showed abnormal long-term potentiation-like cortical plasticity in ON l-dopa therapy. The motor cortex in leucine-rich repeat kinase 2 mutated PD patients is strongly disinhibited and hyperexcitable. These abnormalities could be a result of an impairment of inhibitory (gamma-Aminobutyric acid) transmission eventually related to altered neurotransmitter release. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society.

  19. A family of DNA repeats in Aspergillus nidulans has assimilated degenerated retrotransposons

    DEFF Research Database (Denmark)

    Nielsen, M.L.; Hermansen, T.D.; Aleksenko, Alexei Y.

    2001-01-01

    In the course of a chromosomal walk towards the centromere of chromosome IV of Aspergillus nidulans, several cross- hybridizing genomic cosmid clones were isolated. Restriction mapping of two such clones revealed that their restriction patterns were similar in a region of at least 15 kb, indicati......) phenomenon, first described in Neurospora crassa, may have operated in A. nidulans. The data indicate that this family of repeats has assimilated mobile elements that subsequently degenerated but then underwent further duplications as a part of the host repeats....... the presence of a large repeat. The nature of the repeat was further investigated by sequencing and Southern analysis. The study revealed a family of long dispersed repeats with a high degree of sequence similarity. The number and location of the repeats vary between wild isolates. Two copies of the repeat...

  20. Unusual structures are present in DNA fragments containing super-long Huntingtin CAG repeats.

    Directory of Open Access Journals (Sweden)

    Daniel Duzdevich

    2011-02-01

    Full Text Available In the R6/2 mouse model of Huntington's disease (HD, expansion of the CAG trinucleotide repeat length beyond about 300 repeats induces a novel phenotype associated with a reduction in transcription of the transgene.We analysed the structure of polymerase chain reaction (PCR-generated DNA containing up to 585 CAG repeats using atomic force microscopy (AFM. As the number of CAG repeats increased, an increasing proportion of the DNA molecules exhibited unusual structural features, including convolutions and multiple protrusions. At least some of these features are hairpin loops, as judged by cross-sectional analysis and sensitivity to cleavage by mung bean nuclease. Single-molecule force measurements showed that the convoluted DNA was very resistant to untangling. In vitro replication by PCR was markedly reduced, and TseI restriction enzyme digestion was also hindered by the abnormal DNA structures. However, significantly, the DNA gained sensitivity to cleavage by the Type III restriction-modification enzyme, EcoP15I."Super-long" CAG repeats are found in a number of neurological diseases and may also appear through CAG repeat instability. We suggest that unusual DNA structures associated with super-long CAG repeats decrease transcriptional efficiency in vitro. We also raise the possibility that if these structures occur in vivo, they may play a role in the aetiology of CAG repeat diseases such as HD.

  1. simple sequence repeats (EST-SSR)

    African Journals Online (AJOL)

    Yomi

    2012-01-19

    Jan 19, 2012 ... 212 primer pairs selected, based on repeat patterns of n≥8 for di-, tri-, tetra- and penta-nucleotide repeat ... Cluster analysis revealed a high genetic similarity among the sugarcane (Saccharum spp.) breeding lines which could reduce the genetic gain in ..... The multiple allele characteristic of SSR com-.

  2. Repeated Prescribed Burning in Aspen

    Science.gov (United States)

    Donald A. Perala

    1974-01-01

    Infrequent burning weather, low flammability of the aspen-hardwood association, and prolific sprouting and seeding of shrubs and hardwoods made repeated dormant season burning a poor tool to convert good site aspen to conifers. Repeat fall burns for wildlife habitat maintenance is workable if species composition changes are not important.

  3. The influence of learning methods on collaboration: prior repeated retrieval enhances retrieval organization, abolishes collaborative inhibition, and promotes post-collaborative memory.

    Science.gov (United States)

    Congleton, Adam R; Rajaram, Suparna

    2011-11-01

    Research on collaborative memory has unveiled the counterintuitive yet robust phenomenon that collaboration impairs group recall. A candidate explanation for this collaborative inhibition effect is the disruption of people's idiosyncratic retrieval strategies during collaboration, and it is hypothesized that employing methods that improve one's organization protects against retrieval disruption. Here it is investigated how one's learning method during the study phase--defined as either repeatedly studying or repeatedly retrieving information--influences retrieval organization and what effects this has on collaborative recall and post-collaborative individual recall. Results show that repeated retrieval consistently eliminated collaborative inhibition. This enabled participants to gain the most from re-exposure to materials recalled by their partners that they themselves did not recall and led to improvements in their individual memory following collaboration. This repeated retrieval advantage stemmed from the preferential manner in which this learning method strengthened retrieval organization. Findings are also discussed that reveal a relationship between retrieval organization and the interaction observed between learning method and short versus long delay seen in the testing effect literature. Finally, results show that the elusive benefits of cross-cuing during collaboration may be best detected with a longer study-test delay. Together, these findings illuminate when and how collaboration can enhance memory.

  4. Childhood experiences and repeated suicidal behavior

    DEFF Research Database (Denmark)

    Krarup, Gertrud; Nielsen, Bent; Rask, P

    1991-01-01

    The aim of this study was to elucidate the influence of various events in childhood on suicidal behavior in adult age. For this purpose, 99 patients admitted to the Department of Psychiatry of Odense University Hospital after making a suicide attempt were followed for 5 years, to register repeated...... that the psychological climate of the home may be more important than the rupture of early home life. It is noteworthy that the group of repeaters, as against the first-evers, could be characterized by personality disorders and abuse, especially of alcohol: disorders known to be precipitated by a discordant childhood....... It is commonly agreed that the experience in childhood of suicidal behavior among family members or other persons in the close environment is of importance in future suicidal risk. The results of this study indicate that the predictive value of this factor mainly applies to attempts with no fatal outcome...

  5. Repeatability and reliability of muscle relaxation properties induced by motor cortical stimulation.

    Science.gov (United States)

    Molenaar, Joery P; Voermans, Nicol C; de Jong, Lysanne A; Stegeman, Dick F; Doorduin, Jonne; van Engelen, Baziel G

    2018-03-15

    Impaired muscle relaxation is a feature of many neuromuscular disorders. However, there are few tests available to quantify muscle relaxation. Transcranial magnetic stimulation (TMS) of the motor cortex can induce muscle relaxation by abruptly inhibiting corticospinal drive. The aim of our study is to investigate if repeatability and reliability of TMS-induced relaxation is greater than voluntary relaxation. Furthermore, effects of sex, cooling and fatigue on muscle relaxation properties were studied. Muscle relaxation of deep finger flexors was assessed in twenty-five healthy subjects (14 M and 11 F, aged 39.1{plus minus}12.7 and 45.3{plus minus}8.7 years old, respectively) using handgrip dynamometry. All outcome measures showed greater repeatability and reliability in TMS-induced relaxation compared to voluntary relaxation. The within-subject coefficient of variability of normalized peak relaxation rate was lower in TMS-induced relaxation than in voluntary relaxation (3.0 vs 19.7% in men, and 6.1 vs 14.3% in women). The repeatability coefficient was lower (1.3 vs 6.1 s -1 in men and 2.3 vs 3.1 s -1 in women), and the intraclass correlation coefficient was higher (0.95 vs 0.53 in men and 0.78 vs 0.69 in women), for TMS-induced relaxation compared to voluntary relaxation. TMS enabled to demonstrate slowing effects of sex, muscle cooling, and muscle fatigue on relaxation properties that voluntary relaxation could not. In conclusion, repeatability and reliability of TMS-induced muscle relaxation was greater compared to voluntary muscle relaxation. TMS-induced muscle relaxation has the potential to be used in clinical practice for diagnostic purposes and therapy effect monitoring in patients with impaired muscle relaxation.

  6. Army Study Shows Decline In Behavioral Health Stigma

    Science.gov (United States)

    2012-01-01

    Army Study Shows Decline in Behavioral Health Stigma By Rob McIlvaine Army News Service WASHINGTON, Jan. 20, 2012 - A newly released Army study on...conference yesterday. The three-year study outlines the problem of suicide in the Army and related issues of substance abuse, spouse abuse and child abuse...REPORT TYPE 3. DATES COVERED 00-00-2012 to 00-00-2012 4. TITLE AND SUBTITLE Army Study Shows Decline In Behavioral Health Stigma 5a. CONTRACT

  7. Study of Optimal Perimetric Testing in Children (OPTIC: Feasibility, Reliability and Repeatability of Perimetry in Children.

    Directory of Open Access Journals (Sweden)

    Dipesh E Patel

    Full Text Available To investigate feasibility, reliability and repeatability of perimetry in children.A prospective, observational study recruiting 154 children aged 5-15 years, without an ophthalmic condition that affects the visual field (controls, identified consecutively between May 2012 and November 2013 from hospital eye clinics. Perimetry was undertaken in a single sitting, with standardised protocols, in a randomised order using the Humphrey static (SITA 24-2 FAST, Goldmann and Octopus kinetic perimeters. Data collected included test duration, subjective experience and test quality (incorporating examiner ratings on comprehension of instructions, fatigue, response to visual and auditory stimuli, concentration and co-operation to assess feasibility and reliability. Testing was repeated within 6 months to assess repeatability.Overall feasibility was very high (Goldmann=96.1%, Octopus=89% and Humphrey=100% completed the tests. Examiner rated reliability was 'good' in 125 (81.2% children for Goldmann, 100 (64.9% for Octopus and 98 (63.6% for Humphrey perimetry. Goldmann perimetry was the most reliable method in children under 9 years of age. Reliability improved with increasing age (multinomial logistic regression (Goldmann, Octopus and Humphrey, p<0.001. No significant differences were found for any of the three test strategies when examining initial and follow-up data outputs (Bland-Altman plots, n=43, suggesting good test repeatability, although the sample size may preclude detection of a small learning effect.Feasibility and reliability of formal perimetry in children improves with age. By the age of 9 years, all the strategies used here were highly feasible and reliable. Clinical assessment of the visual field is achievable in children as young as 5 years, and should be considered where visual field loss is suspected. Since Goldmann perimetry is the most effective strategy in children aged 5-8 years and this perimeter is no longer available, further

  8. Breaks in the 45S rDNA Lead to Recombination-Mediated Loss of Repeats

    OpenAIRE

    Warmerdam, Daniël O.; van den Berg, Jeroen; Medema, René H.

    2016-01-01

    rDNA repeats constitute the most heavily transcribed region in the human genome. Tumors frequently display elevated levels of recombination in rDNA, indicating that the repeats are a liability to the genomic integrity of a cell. However, little is known about how cells deal with DNA double-stranded breaks in rDNA. Using selective endonucleases, we show that human cells are highly sensitive to breaks in 45S but not the 5S rDNA repeats. We find that homologous recombination inhibits repair of b...

  9. Dietary Components Affect the Plasma and Tissue Levels of Lutein in Aged Rats with Lutein Deficiency--A Repeated Gavage and Dietary Study.

    Science.gov (United States)

    Sheshappa, Mamatha Bangera; Ranganathan, Arunkumar; Bhatiwada, Nidhi; Talahalli, Ramprasad Ravichandra; Vallikannan, Baskaran

    2015-10-01

    The aim of this study was to find out the influence of selected dietary components on plasma and tissue response of repeated micellar and dietary lutein in aged rats with lutein deficiency. In repeated (16 d) gavage study, micellar lutein was co-ingested with either phosphatidylcholine (PC), lyso-phosphatidylcholine (lysoPC), β-carotene, dietary fiber or vegetable fat (3% soybean oil). In dietary study, rats were fed (4 wk) semi-synthetic diet either with lutein + PC, lutein + dietary fiber or B. alba (lutein source) + PC. The post-prandial plasma and tissue response of lutein was measured by HPLC. Results showed that micellar fat, PC and lysoPC significantly (P ≤ 0.05) increased the lutein levels in plasma (31.1%, 26.8%, and 34.9%), liver (27.4%, 29.5%, and 8.6%), and eyes (63.5%, 90.2%, and 86%) compared to the control group (group gavaged micelles with no dietary components studied). Similarly, dietary study showed an enhanced plasma, liver, and eye lutein levels by 44.8%, 24.1%, and 42.0% (lutein + PC group) and 51.7%, 39.8%, and 31.7% (B.alba + PC group), respectively compared to control. The activity of antioxidant enzymes in plasma and liver of both the studies were also affected compared to control. Result reveals, that PC enhance the intestinal absorption of both micellar and dietary lutein which is either in free or bound form with food matrices in aged rats with lutein deficiency. Hence, PC at a concentration used in this study can be considered to improve the lutein bioavailability in lutein deficiency. Lutein and zeaxanthin are macular pigments acquired mostly from greens, that play an significant role in protecting vision from Age related macular degeneration (AMD). However, their biological availability is poor and affected by dietary components. This study demonstrates the positive influence of dietary PC and lyso PC in improving intestinal uptake of lutein. Our previous and present finding shows there is a possibility of developing functional

  10. RNA FISH for detecting expanded repeats in human diseases.

    Science.gov (United States)

    Urbanek, Martyna O; Krzyzosiak, Wlodzimierz J

    2016-04-01

    RNA fluorescence in situ hybridization (FISH) is a widely used technique for detecting transcripts in fixed cells and tissues. Many variants of RNA FISH have been proposed to increase signal strength, resolution and target specificity. The current variants of this technique facilitate the detection of the subcellular localization of transcripts at a single molecule level. Among the applications of RNA FISH are studies on nuclear RNA foci in diseases resulting from the expansion of tri-, tetra-, penta- and hexanucleotide repeats present in different single genes. The partial or complete retention of mutant transcripts forming RNA aggregates within the nucleoplasm has been shown in multiple cellular disease models and in the tissues of patients affected with these atypical mutations. Relevant diseases include, among others, myotonic dystrophy type 1 (DM1) with CUG repeats, Huntington's disease (HD) and spinocerebellar ataxia type 3 (SCA3) with CAG repeats, fragile X-associated tremor/ataxia syndrome (FXTAS) with CGG repeats, myotonic dystrophy type 2 (DM2) with CCUG repeats, amyotrophic lateral sclerosis/frontotemporal dementia (ALS/FTD) with GGGGCC repeats and spinocerebellar ataxia type 32 (SCA32) with GGCCUG. In this article, we summarize the results obtained with FISH to examine RNA nuclear inclusions. We provide a detailed protocol for detecting RNAs containing expanded CAG and CUG repeats in different cellular models, including fibroblasts, lymphoblasts, induced pluripotent stem cells and murine and human neuronal progenitors. We also present the results of the first single-molecule FISH application in a cellular model of polyglutamine disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Poor methodological detail precludes experimental repeatability and hampers synthesis in ecology.

    Science.gov (United States)

    Haddaway, Neal R; Verhoeven, Jos T A

    2015-10-01

    Despite the scientific method's central tenets of reproducibility (the ability to obtain similar results when repeated) and repeatability (the ability to replicate an experiment based on methods described), published ecological research continues to fail to provide sufficient methodological detail to allow either repeatability of verification. Recent systematic reviews highlight the problem, with one example demonstrating that an average of 13% of studies per year (±8.0 [SD]) failed to report sample sizes. The problem affects the ability to verify the accuracy of any analysis, to repeat methods used, and to assimilate the study findings into powerful and useful meta-analyses. The problem is common in a variety of ecological topics examined to date, and despite previous calls for improved reporting and metadata archiving, which could indirectly alleviate the problem, there is no indication of an improvement in reporting standards over time. Here, we call on authors, editors, and peer reviewers to consider repeatability as a top priority when evaluating research manuscripts, bearing in mind that legacy and integration into the evidence base can drastically improve the impact of individual research reports.

  12. Effect of repeated forearm muscle cooling on the adaptation of skeletal muscle metabolism in humans

    Science.gov (United States)

    Wakabayashi, Hitoshi; Nishimura, Takayuki; Wijayanto, Titis; Watanuki, Shigeki; Tochihara, Yutaka

    2017-07-01

    This study aimed to investigate the effect of repeated cooling of forearm muscle on adaptation in skeletal muscle metabolism. It is hypothesized that repeated decreases of muscle temperature would increase the oxygen consumption in hypothermic skeletal muscle. Sixteen healthy males participated in this study. Their right forearm muscles were locally cooled to 25 °C by cooling pads attached to the skin. This local cooling was repeated eight times on separate days for eight participants (experimental group), whereas eight controls received no cold exposure. To evaluate adaptation in skeletal muscle metabolism, a local cooling test was conducted before and after the repeated cooling period. Change in oxy-hemoglobin content in the flexor digitorum at rest and during a 25-s isometric handgrip (10% maximal voluntary construction) was measured using near-infrared spectroscopy at every 2 °C reduction in forearm muscle temperature. The arterial blood flow was occluded for 15 s by upper arm cuff inflation at rest and during the isometric handgrip. The oxygen consumption in the flexor digitorum muscle was evaluated by a slope of the oxy-hemoglobin change during the arterial occlusion. In the experimental group, resting oxygen consumption in skeletal muscle did not show any difference between pre- and post-intervention, whereas muscle oxygen consumption during the isometric handgrip was significantly higher in post-intervention than in pre-test from thermoneutral baseline to 31 °C muscle temperature ( P cooling might facilitate oxidative metabolism in the skeletal muscle. In summary, skeletal muscle metabolism during submaximal isometric handgrip was facilitated after repeated local muscle cooling.

  13. New polymorphisms within the variable number tandem repeat (VNTR) 7 locus of Mycobacterium avium subsp. paratuberculosis.

    Science.gov (United States)

    Fawzy, Ahmad; Zschöck, Michael; Ewers, Christa; Eisenberg, Tobias

    2016-06-01

    Variable number tandem repeat (VNTR) is a frequently employed typing method of Mycobacterium avium paratuberculosis (MAP) isolates. Based on whole genome sequencing in a previous study, allelic diversity at some VNTR loci seems to over- or under-estimate the actual phylogenetic variance among isolates. Interestingly, two closely related isolates on one farm showed polymorphism at the VNTR 7 locus, raising concerns about the misleading role that it might play in genotyping. We aimed to investigate the underlying basis of VNTR 7-polymorphism by analyzing sequence data for published genomes and field isolates of MAP and other M. avium complex (MAC) members. In contrast to MAP strains from cattle, strains from sheep displayed an "imperfect" repeat within VNTR 7, which was identical to respective allele types in other MAC genomes. Subspecies- and strain-specific single nucleotide polymorphisms (SNPs) and two novel (16 and 56 bp) repeats were detected. Given the combination of the three existing repeats, there are at least five different patterns for VNTR 7. The present findings highlight a higher polymorphism and probable instability of VNTR 7 locus that needs to be considered and challenged in future studies. Until then, sequencing of this locus in future studies is important to correctly assign the underlying allele types.(1). Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Deception and Retribution in Repeated Ultimatum Bargaining.

    Science.gov (United States)

    Boles; Croson; Murnighan

    2000-11-01

    This paper investigates the dynamics of deception and retribution in repeated ultimatum bargaining. Anonymous dyads exchanged messages and offers in a series of four ultimatum bargaining games that had prospects for relatively large monetary outcomes. Variations in each party's knowledge of the other's resources and alternatives created opportunities for deception. Revelation of prior unknowns exposed deceptions and created opportunities for retribution in subsequent interactions. Results showed that although proposers and responders chose deceptive strategies almost equally, proposers told more outright lies. Both were more deceptive when their private information was never revealed, and proposers were most deceptive when their potential profits were largest. Revelation of proposers' lies had little effect on their subsequent behavior even though responders rejected their offers more than similar offers from truthful proposers or proposers whose prior deceit was never revealed. The discussion and conclusions address the dynamics of deception and retribution in repeated bargaining interactions. Copyright 2000 Academic Press.

  15. The Pentapeptide Repeat Proteins

    OpenAIRE

    Vetting, Matthew W.; Hegde, Subray S.; Fajardo, J. Eduardo; Fiser, Andras; Roderick, Steven L.; Takiff, Howard E.; Blanchard, John S.

    2006-01-01

    The Pentapeptide Repeat Protein (PRP) family has over 500 members in the prokaryotic and eukaryotic kingdoms. These proteins are composed of, or contain domains composed of, tandemly repeated amino acid sequences with a consensus sequence of [S,T,A,V][D,N][L,F]-[S,T,R][G]. The biochemical function of the vast majority of PRP family members is unknown. The three-dimensional structure of the first member of the PRP family was determined for the fluoroquinolone resistance protein (MfpA) from Myc...

  16. Repeat cesarean delivery: what indications are recorded in the medical chart?

    Science.gov (United States)

    Lydon-Rochelle, Mona T; Gardella, Carolyn; Cárdenas, Vicky; Easterling, Thomas R

    2006-03-01

    National surveillance estimates reported a troubling 63 percent decline in the rate of vaginal birth after cesarean delivery (VBAC) from 1996 (28.3%) to 2003 (10.6%), with subsequent rising rates of repeat cesarean delivery. The study objective was to examine patterns of documented indications for repeat cesarean delivery in women with and without labor. We conducted a population-based validation study of 19 nonfederal short-stay hospitals in Washington state. Of the 4,541 women who had live births in 2000, 11 percent (n = 493) had repeat cesarean without labor and 3 percent (n = 138) had repeat cesarean with labor. Incidence of medical conditions and pregnancy complications, patterns of documented indications for repeat cesarean delivery, and perioperative complications in relation to repeat cesarean delivery with and without labor were calculated. Of the 493 women who underwent a repeat cesarean delivery without labor, "elective"(36%) and "maternal request"(18%) were the most common indications. Indications for maternal medical conditions (3.0%) were uncommon. Among the 138 women with repeat cesarean delivery with labor, 60.1 percent had failure to progress, 24.6 percent a non-reassuring fetal heart rate, 8.0 percent cephalopelvic disproportion, and 7.2 percent maternal request during labor. Fetal indications were less common (5.8%). Breech, failed vacuum, abruptio placentae, maternal complications, and failed forceps were all indicated less than 5.0 percent. Women's perioperative complications did not vary significantly between women without and with labor. Regardless of a woman's labor status, nearly 10 percent of women with repeat cesarean delivery had no documented indication as to why a cesarean delivery was performed. "Elective" and "maternal request" were common indications among women undergoing repeat cesarean delivery without labor, and nearly 10 percent of women had undocumented indications for repeat cesarean delivery in their medical record

  17. The "saying is repeating" effect: dyadic communication can generate cultural stereotypes.

    Science.gov (United States)

    Bratanova, Boyka; Kashima, Yoshi

    2014-01-01

    It has been long established that interpersonal communication underpins the existence of cultural stereotypes. However, research has either examined the formation of new or the maintenance of existing stereotypes. In a series of three studies, the present research bridges the gap between these phases by showing that newly formed stereotypes can spread through repeated dyadic communication with others. The stereotypic representation arose due to the audience tuning in to communication to a first audience. Further transmission to two types of subsequent audiences was simulated: a newcomer and an old-timer with an unknown attitude towards the target. A "saying-is-repeating" effect was obtained: the stereotypic representation was invariably transmitted to the newcomer, regardless of whether communicators personally believed in the bias; perceived group-level consensus moderated its transmission to the old-timer. These findings demonstrate that once a stereotypic representation is formed, it is likely to spread in a community and potentially become a cultural stereotype.

  18. Repeatability and consistency of individual behaviour in juvenile and adult Eurasian harvest mice

    Science.gov (United States)

    Schuster, Andrea C.; Carl, Teresa; Foerster, Katharina

    2017-04-01

    Knowledge on animal personality has provided new insights into evolutionary biology and animal ecology, as behavioural types have been shown to affect fitness. Animal personality is characterized by repeatable and consistent between-individual behavioural differences throughout time and across different situations. Behavioural repeatability within life history stages and consistency between life history stages should be checked for the independence of sex and age, as recent data have shown that males and females in some species may differ in the repeatability of behavioural traits, as well as in their consistency. We measured the repeatability and consistency of three behavioural and one cognitive traits in juvenile and adult Eurasian harvest mice ( Micromys minutus). We found that exploration, activity and boldness were repeatable in juveniles and adults. Spatial recognition measured in a Y Maze was only repeatable in adult mice. Exploration, activity and boldness were consistent before and after maturation, as well as before and after first sexual contact. Data on spatial recognition provided little evidence for consistency. Further, we found some evidence for a litter effect on behaviours by comparing different linear mixed models. We concluded that harvest mice express animal personality traits as behaviours were repeatable across sexes and consistent across life history stages. The tested cognitive trait showed low repeatability and was less consistent across life history stages. Given the rising interest in individual variation in cognitive performance, and in its relationship to animal personality, we suggest that it is important to gather more data on the repeatability and consistency of cognitive traits.

  19. RePS: a sequence assembler that masks exact repeats identified from the shotgun data

    DEFF Research Database (Denmark)

    Wang, Jun; Wong, Gane Ka-Shu; Ni, Peixiang

    2002-01-01

    We describe a sequence assembler, RePS (repeat-masked Phrap with scaffolding), that explicitly identifies exact 20mer repeats from the shotgun data and removes them prior to the assembly. The established software is used to compute meaningful error probabilities for each base. Clone......-end-pairing information is used to construct scaffolds that order and orient the contigs. We show with real data for human and rice that reasonable assemblies are possible even at coverages of only 4x to 6x, despite having up to 42.2% in exact repeats. Udgivelsesdato: 2002-May...

  20. Triage of Women with Low-Grade Cervical Lesions - HPV mRNA Testing versus Repeat Cytology

    Science.gov (United States)

    Sørbye, Sveinung Wergeland; Arbyn, Marc; Fismen, Silje; Gutteberg, Tore Jarl; Mortensen, Elin Synnøve

    2011-01-01

    Background In Norway, women with low-grade squamous intraepithelial lesions (LSIL) are followed up after six months in order to decide whether they should undergo further follow-up or be referred back to the screening interval of three years. A high specificity and positive predictive value (PPV) of the triage test is important to avoid unnecessary diagnostic and therapeutic procedures. Materials and Methods At the University Hospital of North Norway, repeat cytology and the HPV mRNA test PreTect HPV-Proofer, detecting E6/E7 mRNA from HPV types 16, 18, 31, 33 and 45, are used in triage of women with ASC-US and LSIL. In this study, women with LSIL cytology in the period 2005–2008 were included (n = 522). Two triage methods were evaluated in two separate groups: repeat cytology only (n = 225) and HPV mRNA testing in addition to repeat cytology (n = 297). Histologically confirmed cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) was used as the study endpoint. Results Of 522 women with LSIL, 207 had biopsies and 125 of them had CIN2+. The sensitivity and specificity of repeat cytology (ASC-US or worse) were 85.7% (95% confidence interval (CI): 72.1, 92.2) and 54.4 % (95% CI: 46.9, 61.9), respectively. The sensitivity and specificity of the HPV mRNA test were 94.2% (95% CI: 88.7, 99.7) and 86.0% (95% CI: 81.5, 90.5), respectively. The PPV of repeat cytology was 38.4% (95% CI: 29.9, 46.9) compared to 67.0% (95% CI: 57.7, 76.4) of the HPV mRNA test. Conclusion HPV mRNA testing was more sensitive and specific than repeat cytology in triage of women with LSIL cytology. In addition, the HPV mRNA test showed higher PPV. These data indicate that the HPV mRNA test is a better triage test for women with LSIL than repeat cytology. PMID:21918682

  1. Enhanced appetitive conditioning following repeated pretreatment with d-amphetamine.

    Science.gov (United States)

    Harmer, C J; Phillips, G D

    1998-07-01

    The behavioural response to psychomotor stimulants is augmented with repeated exposure to these drugs. Enhanced stimulated dopamine overflow within the nucleus accumbens and amygdala has been found to accompany this behavioural sensitization. In the present experiment, rats received 2 mg/kg d-amphetamine or 1 ml/kg physiological saline once per day for 5 days. Five days later, a behavioural assay confirmed that prior repeated d-amphetamine treatment markedly enhanced the locomotor activating effects of a d-amphetamine (0.5 mg/kg, i.p.) challenge. Training on a Pavlovian conditioning task began six days subsequently. In Stage 1, a stimulus (light or tone, S-) was presented negatively correlated with a sucrose reward. In Stage 2, presentation of the alternative counterbalanced stimulus (light or tone, S+) was paired with the availability of a 10% sucrose solution. There were no differences between the two groups in their response to the the S- stimulus. However, sensitized animals showed a selective enhancement in the acquisition of conditioned responding to S+, relative to vehicle-injected controls. No differences in behaviour were recorded during the prestimulus periods, nor during presentations of sucrose. Levels of activity within the operant chamber extraneous to alcove approach were also similar in both groups of animals. The conditioned instrumental efficacy of S+, relative to S- was assessed in Stage 3, in which stimulus availability was made contingent on a novel lever-pressing response. Both groups showed a similar preference for the S+ over the S- stimulus. Hence, rats sensitized by prior repeated d-amphetamine showed enhanced appetitive Pavlovian conditioning, without subsequent effect on conditioned reward efficacy. These data are discussed in light of possible changes in mesoamygdaloid dopamine functioning.

  2. Repeated superovulation increases the risk of osteoporosis and cardiovascular diseases by accelerating ovarian aging in mice.

    Science.gov (United States)

    Zhang, Jinjin; Lai, Zhiwen; Shi, Liangyan; Tian, Yong; Luo, Aiyue; Xu, Zheyuan; Ma, Xiangyi; Wang, Shixuan

    2018-05-22

    Superovulation procedures and assisted reproductive technologies have been widely used to treat couples who have infertility problems. Although generally safe, the superovulation procedures are associated with a series of complications, such as ovarian hyper-stimulation syndrome, thromboembolism, and adnexal torsion. The role of long-term repeated superovulation in ovarian aging and especially in associated disorders such as osteoporosis and cardiovascular diseases is still unclear. In this study, we sought to determine if repeated superovulation by ten cycles of treatment with pregnant mare serum gonadotropin/human chorionic gonadotropin could affect ovarian reserve, ovarian function, bone density and heart function. Ovarian reserve and function were reflected by the size of the primordial follicle pool, anti-Mullerian hormone expressions, hormone levels and fertility status. Furthermore, we examined bone density and heart function by microCT and cardiovascular ultrasonography, respectively. After repeated superovulation, the size of the primordial follicle pool and the expression of anti-mullerian hormone decreased, along with the concentrations of estrogen and progesterone. Mice exposed to repeated superovulation showed an obvious decrease in fertility and fecundity. Furthermore, both bone density and heart ejection fraction significantly decreased. These results suggest that repeated superovulation may increase the risk of osteoporosis and cardiovascular diseases by accelerating ovarian aging.

  3. Impact of Alu repeats on the evolution of human p53 binding sites

    Directory of Open Access Journals (Sweden)

    Sirotin Michael V

    2011-01-01

    Full Text Available Abstract Background The p53 tumor suppressor protein is involved in a complicated regulatory network, mediating expression of ~1000 human genes. Recent studies have shown that many p53 in vivo binding sites (BSs reside in transposable repeats. The relationship between these BSs and functional p53 response elements (REs remains unknown, however. We sought to understand whether the p53 REs also reside in transposable elements and particularly in the most-abundant Alu repeats. Results We have analyzed ~160 functional p53 REs identified so far and found that 24 of them occur in repeats. More than half of these repeat-associated REs reside in Alu elements. In addition, using a position weight matrix approach, we found ~400,000 potential p53 BSs in Alu elements genome-wide. Importantly, these putative BSs are located in the same regions of Alu repeats as the functional p53 REs - namely, in the vicinity of Boxes A/A' and B of the internal RNA polymerase III promoter. Earlier nucleosome-mapping experiments showed that the Boxes A/A' and B have a different chromatin environment, which is critical for the binding of p53 to DNA. Here, we compare the Alu-residing p53 sites with the corresponding Alu consensus sequences and conclude that the p53 sites likely evolved through two different mechanisms - the sites overlapping with the Boxes A/A' were generated by CG → TG mutations; the other sites apparently pre-existed in the progenitors of several Alu subfamilies, such as AluJo and AluSq. The binding affinity of p53 to the Alu-residing sites generally correlates with the age of Alu subfamilies, so that the strongest sites are embedded in the 'relatively young' Alu repeats. Conclusions The primate-specific Alu repeats play an important role in shaping the p53 regulatory network in the context of chromatin. One of the selective factors responsible for the frequent occurrence of Alu repeats in introns may be related to the p53-mediated regulation of Alu

  4. Genetic Contributors to Intergenerational CAG Repeat Instability in Huntington's Disease Knock-In Mice.

    Science.gov (United States)

    Neto, João Luís; Lee, Jong-Min; Afridi, Ali; Gillis, Tammy; Guide, Jolene R; Dempsey, Stephani; Lager, Brenda; Alonso, Isabel; Wheeler, Vanessa C; Pinto, Ricardo Mouro

    2017-02-01

    Huntington's disease (HD) is a neurodegenerative disorder caused by the expansion of a CAG trinucleotide repeat in exon 1 of the HTT gene. Longer repeat sizes are associated with increased disease penetrance and earlier ages of onset. Intergenerationally unstable transmissions are common in HD families, partly underlying the genetic anticipation seen in this disorder. HD CAG knock-in mouse models also exhibit a propensity for intergenerational repeat size changes. In this work, we examine intergenerational instability of the CAG repeat in over 20,000 transmissions in the largest HD knock-in mouse model breeding datasets reported to date. We confirmed previous observations that parental sex drives the relative ratio of expansions and contractions. The large datasets further allowed us to distinguish effects of paternal CAG repeat length on the magnitude and frequency of expansions and contractions, as well as the identification of large repeat size jumps in the knock-in models. Distinct degrees of intergenerational instability were observed between knock-in mice of six background strains, indicating the occurrence of trans-acting genetic modifiers. We also found that lines harboring a neomycin resistance cassette upstream of Htt showed reduced expansion frequency, indicative of a contributing role for sequences in cis, with the expanded repeat as modifiers of intergenerational instability. These results provide a basis for further understanding of the mechanisms underlying intergenerational repeat instability. Copyright © 2017 by the Genetics Society of America.

  5. C9orf72 nucleotide repeat structures initiate molecular cascades of disease.

    Science.gov (United States)

    Haeusler, Aaron R; Donnelly, Christopher J; Periz, Goran; Simko, Eric A J; Shaw, Patrick G; Kim, Min-Sik; Maragakis, Nicholas J; Troncoso, Juan C; Pandey, Akhilesh; Sattler, Rita; Rothstein, Jeffrey D; Wang, Jiou

    2014-03-13

    A hexanucleotide repeat expansion (HRE), (GGGGCC)n, in C9orf72 is the most common genetic cause of the neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Here we identify a molecular mechanism by which structural polymorphism of the HRE leads to ALS/FTD pathology and defects. The HRE forms DNA and RNA G-quadruplexes with distinct structures and promotes RNA•DNA hybrids (R-loops). The structural polymorphism causes a repeat-length-dependent accumulation of transcripts aborted in the HRE region. These transcribed repeats bind to ribonucleoproteins in a conformation-dependent manner. Specifically, nucleolin, an essential nucleolar protein, preferentially binds the HRE G-quadruplex, and patient cells show evidence of nucleolar stress. Our results demonstrate that distinct C9orf72 HRE structural polymorphism at both DNA and RNA levels initiates molecular cascades leading to ALS/FTD pathologies, and provide the basis for a mechanistic model for repeat-associated neurodegenerative diseases.

  6. Breaks in the 45S rDNA Lead to Recombination-Mediated Loss of Repeats

    Directory of Open Access Journals (Sweden)

    Daniël O. Warmerdam

    2016-03-01

    Full Text Available rDNA repeats constitute the most heavily transcribed region in the human genome. Tumors frequently display elevated levels of recombination in rDNA, indicating that the repeats are a liability to the genomic integrity of a cell. However, little is known about how cells deal with DNA double-stranded breaks in rDNA. Using selective endonucleases, we show that human cells are highly sensitive to breaks in 45S but not the 5S rDNA repeats. We find that homologous recombination inhibits repair of breaks in 45S rDNA, and this results in repeat loss. We identify the structural maintenance of chromosomes protein 5 (SMC5 as contributing to recombination-mediated repair of rDNA breaks. Together, our data demonstrate that SMC5-mediated recombination can lead to error-prone repair of 45S rDNA repeats, resulting in their loss and thereby reducing cellular viability.

  7. D20S16 is a complex interspersed repeated sequence: Genetic and physical analysis of the locus

    Energy Technology Data Exchange (ETDEWEB)

    Bowden, D.W.; Krawchuk, M.D.; Howard, T.D. [Wake Forest Univ., Winston-Salem, NC (United States)] [and others

    1995-01-20

    The genomic structure of the D20S16 locus has been evaluated using genetic and physical methods. D20S16, originally detected with the probe CRI-L1214, is a highly informative, complex restriction fragment length polymorphism consisting of two separate allelic systems. The allelic systems have the characteristics of conventional VNTR polymorphisms and are separated by recombination ({theta} = 0.02, Z{sub max} = 74.82), as demonstrated in family studies. Most of these recombination events are meiotic crossovers and are maternal in origin, but two, including deletion of the locus in a cell line from a CEPH family member, occur without evidence for exchange of flanking markers. DNA sequence analysis suggests that the basis of the polymorphism is variable numbers of a 98-bp sequence tandemly repeated with 87 to 90% sequence similarity between repeats. The 98-bp repeat is a dimer of 49 bp sequence with 45 to 98% identity between the elements. In addition, nonpolymorphic genomic sequences adjacent to the polymorphic 98-bp repeat tracts are also repeated but are not polymorphic, i.e., show no individual to individual variation. Restriction enzyme mapping of cosmids containing the CRI-L1214 sequence suggests that there are multiple interspersed repeats of the CRI-L1214 sequence on chromosome 20. The results of dual-color fluorescence in situ hybridization experiments with interphase nuclei are also consistent with multiple repeats of an interspersed sequence on chromosome 20. 23 refs., 6 figs.

  8. Dealing with consumer differences in liking during repeated exposure to food; typical dynamics in rating behavior

    NARCIS (Netherlands)

    Horst, ter G.J.; Renken, R.; Nanneti, L.; Dalenberg, J.R.; Wijk, de R.A.

    2014-01-01

    Consumers show high interindividual variability in food liking during repeated exposure. To investigate consumer liking during repeated exposure, data is often interpreted on a product level by averaging results over all consumers. However, a single product may elicit inconsistent behaviors in

  9. Dealing with Consumer Differences in Liking during Repeated Exposure to Food; Typical Dynamics in Rating Behavior

    NARCIS (Netherlands)

    Dalenberg, Jelle R.; Nanetti, Luca; Renken, Remco J.; de Wijk, Rene A.; ter Horst, Gert J.

    2014-01-01

    Consumers show high interindividual variability in food liking during repeated exposure. To investigate consumer liking during repeated exposure, data is often interpreted on a product level by averaging results over all consumers. However, a single product may elicit inconsistent behaviors in

  10. A Large Complement of the Predicted Arabidopsis ARM Repeat Proteins Are Members of the U-Box E3 Ubiquitin Ligase Family1[w

    Science.gov (United States)

    Mudgil, Yashwanti; Shiu, Shin-Han; Stone, Sophia L.; Salt, Jennifer N.; Goring, Daphne R.

    2004-01-01

    The Arabidopsis genome was searched to identify predicted proteins containing armadillo (ARM) repeats, a motif known to mediate protein-protein interactions in a number of different animal proteins. Using domain database predictions and models generated in this study, 108 Arabidopsis proteins were identified that contained a minimum of two ARM repeats with the majority of proteins containing four to eight ARM repeats. Clustering analysis showed that the 108 predicted Arabidopsis ARM repeat proteins could be divided into multiple groups with wide differences in their domain compositions and organizations. Interestingly, 41 of the 108 Arabidopsis ARM repeat proteins contained a U-box, a motif present in a family of E3 ligases, and these proteins represented the largest class of Arabidopsis ARM repeat proteins. In 14 of these U-box/ARM repeat proteins, there was also a novel conserved domain identified in the N-terminal region. Based on the phylogenetic tree, representative U-box/ARM repeat proteins were selected for further study. RNA-blot analyses revealed that these U-box/ARM proteins are expressed in a variety of tissues in Arabidopsis. In addition, the selected U-box/ARM proteins were found to be functional E3 ubiquitin ligases. Thus, these U-box/ARM proteins represent a new family of E3 ligases in Arabidopsis. PMID:14657406

  11. Readout Distance Enhancement of the Passive Wireless Multi-Parameter Sensing System Using a Repeater Coil

    Directory of Open Access Journals (Sweden)

    Lifeng Wang

    2018-01-01

    Full Text Available A repeater coil is used to extend the detection distance of a passive wireless multi-parameter sensing system. The passive wireless sensing system has the ability of simultaneously monitoring three parameters by using backscatter modulation together with channel multiplexing. Two different repeater coils are designed and fabricated for readout distance enhancement of the sensing system: one is a PCB (printed circuit board repeater coil, and the other is a copper wire repeater coil. Under the conditions of fixed voltage and adjustable voltage, the maximum readout distance of the sensing system with and without a repeater coil is measured. Experimental results show that larger power supply voltage can help further increase the readout distance. The maximum readout distance of the sensing system with a PCB repeater coil has been extended 2.3 times, and the one with a copper wire repeater coil has been extended 3 times. Theoretical analysis and experimental results both indicate that the high Q factor repeater coil can extend the readout distance more. With the copper wire repeater coil as well as a higher power supply voltage, the passive wireless multi-parameter sensing system finally achieves a maximum readout distance of 13.5 cm.

  12. Repeat-mediated epigenetic dysregulation of the FMR1 gene in the fragile X-related disorders.

    Science.gov (United States)

    Usdin, Karen; Kumari, Daman

    2015-01-01

    The fragile X-related disorders are members of the Repeat Expansion Diseases, a group of genetic conditions resulting from an expansion in the size of a tandem repeat tract at a specific genetic locus. The repeat responsible for disease pathology in the fragile X-related disorders is CGG/CCG and the repeat tract is located in the 5' UTR of the FMR1 gene, whose protein product FMRP, is important for the proper translation of dendritic mRNAs in response to synaptic activation. There are two different pathological FMR1 allele classes that are distinguished only by the number of repeats. Premutation alleles have 55-200 repeats and confer risk of fragile X-associated tremor/ataxia syndrome and fragile X-associated primary ovarian insufficiency. Full mutation alleles on the other hand have >200 repeats and result in fragile X syndrome, a disorder that affects learning and behavior. Different symptoms are seen in carriers of premutation and full mutation alleles because the repeat number has paradoxical effects on gene expression: Epigenetic changes increase transcription from premutation alleles and decrease transcription from full mutation alleles. This review will cover what is currently known about the mechanisms responsible for these changes in FMR1 expression and how they may relate to other Repeat Expansion Diseases that also show repeat-mediated changes in gene expression.

  13. RECG maintains plastid and mitochondrial genome stability by suppressing extensive recombination between short dispersed repeats.

    Directory of Open Access Journals (Sweden)

    Masaki Odahara

    2015-03-01

    Full Text Available Maintenance of plastid and mitochondrial genome stability is crucial for photosynthesis and respiration, respectively. Recently, we have reported that RECA1 maintains mitochondrial genome stability by suppressing gross rearrangements induced by aberrant recombination between short dispersed repeats in the moss Physcomitrella patens. In this study, we studied a newly identified P. patens homolog of bacterial RecG helicase, RECG, some of which is localized in both plastid and mitochondrial nucleoids. RECG partially complements recG deficiency in Escherichia coli cells. A knockout (KO mutation of RECG caused characteristic phenotypes including growth delay and developmental and mitochondrial defects, which are similar to those of the RECA1 KO mutant. The RECG KO cells showed heterogeneity in these phenotypes. Analyses of RECG KO plants showed that mitochondrial genome was destabilized due to a recombination between 8-79 bp repeats and the pattern of the recombination partly differed from that observed in the RECA1 KO mutants. The mitochondrial DNA (mtDNA instability was greater in severe phenotypic RECG KO cells than that in mild phenotypic ones. This result suggests that mitochondrial genomic instability is responsible for the defective phenotypes of RECG KO plants. Some of the induced recombination caused efficient genomic rearrangements in RECG KO mitochondria. Such loci were sometimes associated with a decrease in the levels of normal mtDNA and significant decrease in the number of transcripts derived from the loci. In addition, the RECG KO mutation caused remarkable plastid abnormalities and induced recombination between short repeats (12-63 bp in the plastid DNA. These results suggest that RECG plays a role in the maintenance of both plastid and mitochondrial genome stability by suppressing aberrant recombination between dispersed short repeats; this role is crucial for plastid and mitochondrial functions.

  14. Effect of Beta alanine and sodium bicarbonate supplementation on repeated-sprint performance.

    Science.gov (United States)

    Ducker, Kagan J; Dawson, Brian; Wallman, Karen E

    2013-12-01

    This study aimed to investigate if combining beta alanine (BA) and sodium bicarbonate (NaHCO3) supplementation could lead to enhanced repeated-sprint performance in team-sport athletes, beyond what is possible with either supplement alone. Participants (n = 24) completed duplicate trials of a repeated-sprint test (3 sets; 6 × 20 m departing every 25 seconds, 4 minutes active recovery between sets) and were then allocated into 4 groups as follows: BA only (n = 6; 28 days BA, acute sodium chloride placebo); NaHCO3 only (n = 6; 28 days glucose placebo, acute NaHCO3); BA/NaHCO3 (n = 6; 28 days BA, acute NaHCO3); placebo only (n = 6; 28 days glucose placebo, acute sodium chloride placebo), then completed duplicate trials postsupplementation. Sodium bicarbonate alone resulted in moderate effect size (d = 0.40-0.71) and "likely" and "very likely" benefit for overall total sprint times (TST) and for each individual set and for first sprint (sets 2 and 3) and best sprint time (sets 2 and 3). Combining BA and NaHCO3 resulted in "possible" to "likely" benefits for overall TST and for sets 2 and 3. First sprint (set 3) and best sprint time (sets 2 and 3) also showed "likely" benefit after this trial. The BA and placebo groups showed no differences in performance after supplementation. In conclusion, these results indicate that supplementation with acute NaHCO3 improved repeated-sprint performance more than either a combination of NaHCO3 and BA or BA alone.

  15. In situ detection of tandem DNA repeat length

    Energy Technology Data Exchange (ETDEWEB)

    Yaar, R.; Szafranski, P.; Cantor, C.R.; Smith, C.L. [Boston Univ., MA (United States)

    1996-11-01

    A simple method for scoring short tandem DNA repeats is presented. An oligonucleotide target, containing tandem repeats embedded in a unique sequence, was hybridized to a set of complementary probes, containing tandem repeats of known lengths. Single-stranded loop structures formed on duplexes containing a mismatched (different) number of tandem repeats. No loop structure formed on duplexes containing a matched (identical) number of tandem repeats. The matched and mismatched loop structures were enzymatically distinguished and differentially labeled by treatment with S1 nuclease and the Klenow fragment of DNA polymerase. 7 refs., 4 figs.

  16. [Toxicity studies of landiolol hydrochloride (ONO-1101) (2). 4-week repeated dose intravenous toxicity study in rats with 4-week recovery test].

    Science.gov (United States)

    Yamaguchi, K; Yanagi, H; Shimizu, K; Sakai, M; Nishibata, K; Oida, H; Shinomiya, K; Suzuki, Y; Yonezawa, H; Fujita, T

    1997-12-01

    4-week repeated dose toxicity study with 4-week recovery test of landiolol hydrochloride (ONO-1101), a novel ultra short acting beta-blocker, was conducted in Sprague-Dawley (SD) rats. ONO-1101 was administered intravenously to rats of both sexes at a dose level of 0 (control), 12.5, 25, 50 or 100 mg/kg/day. In the 100 mg/kg/day group, bradypnea or dyspnea was seen in all animals, pale in ear, eye and foot, tremor, reddish lacrimation and loss of righting reflex were also observed in some animals right after administration, and then those signs disappeared within 1 min after administration. During the treatment period, 3/20 animals of each sex in the 100 mg/kg/day showed clonic convulsion and died within 2 min after administration. No clinical changes were seen in the 50 mg/kg/day group or lower. Histopathological findings showed atrophy of the submaxillary gland in females and vessel-wall thickening and perivascular fibrosis of the injection site (tail) in both sexes at 100 mg/kg/day, however those changes were reversible. ONO-1101 did not effect on body weight, food consumption, ophthalmology, urinalysis, hematology, blood chemistry, organ weights or necropsy at any doses. These results indicate that the no-adverse-effect level of ONO-1101 in rats is 50 mg/kg/day for both sexes in this study.

  17. Repeatability and reproducibility of ribotyping and its computer interpretation.

    Science.gov (United States)

    Lefresne, Gwénola; Latrille, Eric; Irlinger, Françoise; Grimont, Patrick A D

    2004-04-01

    Many molecular typing methods are difficult to interpret because their repeatability (within-laboratory variance) and reproducibility (between-laboratory variance) have not been thoroughly studied. In the present work, ribotyping of coryneform bacteria was the basis of a study involving within-gel and between-gel repeatability and between-laboratory reproducibility (two laboratories involved). The effect of different technical protocols, different algorithms, and different software for fragment size determination was studied. Analysis of variance (ANOVA) showed, within a laboratory, that there was no significant added variance between gels. However, between-laboratory variance was significantly higher than within-laboratory variance. This may be due to the use of different protocols. An experimental function was calculated to transform the data and make them compatible (i.e., erase the between-laboratory variance). The use of different interpolation algorithms (spline, Schaffer and Sederoff) was a significant source of variation in one laboratory only. The use of either Taxotron (Institut Pasteur) or GelCompar (Applied Maths) was not a significant source of added variation when the same algorithm (spline) was used. However, the use of Bio-Gene (Vilber Lourmat) dramatically increased the error (within laboratory, within gel) in one laboratory, while decreasing the error in the other laboratory; this might be due to automatic normalization attempts. These results were taken into account for building a database and performing automatic pattern identification using Taxotron. Conversion of the data considerably improved the identification of patterns irrespective of the laboratory in which the data were obtained.

  18. Repeatability of tumour hypoxia imaging using [{sup 18}F]EF5 PET/CT in head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Silvoniemi, Antti [University of Turku, Turku PET Centre (Finland); Turku University Hospital, Department of Otorhinolaryngology - Head and Neck Surgery (Finland); Suilamo, Sami [Turku University Hospital, Department of Oncology and Radiotherapy (Finland); Turku University Hospital, Department of Medical Physics (Finland); Laitinen, Timo; Forsback, Sarita; Solin, Olof [University of Turku, Turku PET Centre (Finland); Loeyttyniemi, Eliisa [University of Turku, Department of Biostatistics, Turku (Finland); Vaittinen, Samuli [Turku University Hospital, Department of Pathology (Finland); Saunavaara, Virva [University of Turku, Turku PET Centre (Finland); Turku University Hospital, Department of Medical Physics (Finland); Groenroos, Tove J.; Minn, Heikki [University of Turku, Turku PET Centre (Finland); Turku University Hospital, Department of Oncology and Radiotherapy (Finland)

    2018-02-15

    Hypoxia contributes to radiotherapy resistance and more aggressive behaviour of several types of cancer. This study was designed to evaluate the repeatability of intratumour uptake of the hypoxia tracer [{sup 18}F]EF5 in paired PET/CT scans. Ten patients with newly diagnosed head and neck cancer (HNC) received three static PET/CT scans before chemoradiotherapy: two with [{sup 18}F]EF5 a median of 7 days apart and one with [{sup 18}F]FDG. Metabolically active primary tumour volumes were defined in [{sup 18}F]FDG images and transferred to co-registered [{sup 18}F]EF5 images for repeatability analysis. A tumour-to-muscle uptake ratio (TMR) of 1.5 at 3 h from injection of [{sup 18}F]EF5 was used as a threshold representing hypoxic tissue. In 10 paired [{sup 18}F]EF5 PET/CT image sets, SUVmean, SUVmax, and TMR showed a good correlation with the intraclass correlation coefficients of 0.81, 0.85, and 0.87, respectively. The relative coefficients of repeatability for these parameters were 15%, 17%, and 10%, respectively. Fractional hypoxic volumes of the tumours in the repeated scans had a high correlation using the Spearman rank correlation test (r = 0.94). In a voxel-by-voxel TMR analysis between the repeated scans, the mean of Pearson correlation coefficients of individual patients was 0.65. The mean (± SD) difference of TMR in the pooled data set was 0.03 ± 0.20. Pretreatment [{sup 18}F]EF5 PET/CT within one week shows high repeatability and is feasible for the guiding of hypoxia-targeted treatment interventions in HNC. (orig.)

  19. The usefulness of repeated ictal SPET for the localization of epileptogenic zones in intractable epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Soo; Chung, June-Key; Lee, Myung Chul [Institute of Radiation Medicine, Seoul National University Medical Research Center (Korea); Department of Nuclear Medicine, Seoul National University College of Medicine (Korea); Lee, Sang Kun [Department of Neurology, Seoul National University College of Medicine (Korea); Kim, Yu Kyeong [Department of Nuclear Medicine, Seoul National University College of Medicine (Korea); Kang, Eunjoo; Lee, Jae Sung [Institute of Radiation Medicine, Seoul National University Medical Research Center (Korea)

    2002-05-01

    nine patients, while in the other three it was not. Among group II, six patients showed the same results at the second study, thus confirming that the initially identified zones were of epileptogenic significance. In the other six patients, different areas were identified on the first and second studies, and repeated ictal SPET corroborated multifocality of the ictal EEG findings in five. These results indicate that repeated ictal SPET is useful because it can yield new or additional information about the epileptogenic zones and can confirm that a region of interest is an epileptogenic zone or that the epilepsy is of multifocal origin. (orig.)

  20. Laxative effect of repeated Daiokanzoto is attributable to decrease in aquaporin-3 expression in the colon.

    Science.gov (United States)

    Kon, Risako; Yamamura, Miho; Matsunaga, Yukari; Kimura, Hiroshi; Minami, Moe; Kato, Saki; Ikarashi, Nobutomo; Sugiyama, Kiyoshi

    2018-03-01

    Daiokanzoto (DKT) exerts its laxative effect via colonic inflammation caused by sennoside A in Daio (rhubarb). Previously, we showed that the laxative effect of sennoside A is related to decreased aquaporin-3 (AQP3) expression in mucosal epithelial cells due to colonic inflammation. We also found that a combination of glycyrrhizin, an ingredient in Kanzo (glycyrrhiza), and sennoside A attenuates the inflammatory response induced by sennoside A and reduces its laxative effect. These findings indicate that DKT may be a long-term treatment for chronic constipation, but there is no evidence supporting this hypothesis. In this study, we analyzed the laxative effect of repeated DKT administration, focusing on AQP3 expression in the colon. After rats were treated for 7 days, decreased AQP3 expression and the onset of diarrhea were observed in the DKT group, but were not seen in the Daio group either. Although the relative abundance of gut microbiota after repeated DKT administration was similar to that after control treatment, Daio reduced Lactobacillaceae, Bifidobacteriaceae, and Bacteroidaceae levels and markedly increased Lachnospiraceae levels. In this study, we show that DKT has a sustained laxative effect, even upon repeated use, probably because it maintains decreased AQP3 expression and gut microbiota homeostasis. This outcome therefore indicates that DKT can be used as a long-term treatment for chronic constipation.

  1. Thyroid nodules with nondiagnostic results on repeat fine-needle aspiration biopsy: which nodules should be considered for repeat biopsy or surgery rather than follow-up?

    Energy Technology Data Exchange (ETDEWEB)

    Eun, Na Lae; Chang, Hang Seok; Gweon, Hye Mi; Kim, Jeong Ah; Youk, Ji Hyun; Son, Eun Jun [Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Yoo, Mi Ri [Dept. of Radiology, Dongjak Kyunghee Hospital, Seoul (Korea, Republic of); Park, Ah Young [Dept. of Radiology, Korea University Ansan Hospital, Korea University College of Medicine, Ansan (Korea, Republic of); Moon, Hee Jung [Dept. of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2016-07-15

    The goal of this study was to assess the clinicopathologic and ultrasonographic features of thyroid nodules with nondiagnostic results on repeat ultrasonography (US)-guided fineneedle aspiration biopsy (FNAB) according to size and the number of suspicious findings and to determine the proper management of nodules with consecutive nondiagnostic results. This retrospective study included 297 nodules with nondiagnostic results on repeat FNAB that were evaluated by US over the course of at least 12 months of follow-up, a follow-up biopsy, or an operation. We compared clinical and US variables between benign and malignant nodules in thyroid nodules with repeat nondiagnostic results. The comparison of benign and malignant nodules with repeat nondiagnostic results revealed that age, marked hypoechogenicity, irregular or microlobulated margins, microcalcifications, and nonparallel shape were significantly associated with malignancy. Multivariate logistic regression analysis in malignant nodules revealed that microcalcifications and irregular or microlobulated margins were independently associated with malignancy. Among them, only irregular or microlobulated margins were independently significant as a predictor of malignancy in repeatedly nondiagnostic nodules measuring >10 mm. Using receiver operating characteristic analysis, the best cutoff value for the “number of suspicious findings” between benign and malignant nodules was three in nodules of all sizes, three in nodules measuring ≤10 mm, and two in nodules measuring >10 mm. Irregular or microlobulated margins may be the most frequent US features in repeatedly nondiagnostic nodules >10 mm. The presence of “two or more suspicious findings” can be used as the cutoff for distinguishing benign and malignant nodules.

  2. Micronucleus induction by repeated exposure of diagnostic X-ray on oral buccal mucosa

    International Nuclear Information System (INIS)

    Lohith Tejashvi, K.; Suchetha Kumari, N.; Shetty, Shishir Ram

    2012-01-01

    Radiography is the important diagnostic tools essential for diagnosis and planning of orthodontic treatment. X-ray is ionizing radiation which showed various effects include breaking the bond of biological molecules, inducing loss of ability of cell death, increases nuclear alterations. Micronuclei - x000D - (MN) are small chromatin bodies that appear in the cytoplasm by the - x000D - condensation of acrocentric chromosomal fragments or by whole chromosomes. This - x000D - is a sensitive indicator of genetic damage. - x000D - x000D - . To evaluate micronucleus induction by repeated exposure of diagnostic X-ray on human buccal cell. Methods: 25 patients who visiting to ABSMIDS, Department of Oral medicine and Radiology for dental checkup exposed to diagnostic X-ray more than 4 times have been selected for this study. The buccal cell for analysis was collected from the cheek mucosa by means of gentle scraping of epithelial using ice-cream sticks and placed in Buffer saline. This sample was smeared on glass slide and then fixed in methanol:glacial acetic acid (3:1). Air dried and stained with Giemsa for 15-25 minutes. Then 250 cells in each slides were analyzed under microscope and frequency of micronucleus was scored (n=4). Repeated X-ray exposed cells showed micronucleus (1.25%) and nuclear alteration (2.3%) compare to the control. Repeated X-ray exposure leads to induces detectable number of micronucleus and nuclear alterations. (author)

  3. Day-to-day repeatability of the Pulse Time Index of Norm

    Directory of Open Access Journals (Sweden)

    Posokhov IN

    2014-02-01

    Full Text Available Igor N Posokhov,1 Aleksandra O Konradi,2 Eugeny V Shlyakhto,2 Oleg V Mamontov,2 Artemy V Orlov,3 Anatoly N Rogoza4 1Hemodynamic Laboratory Ltd, Nizhniy Novgorod, 2Almazov Federal Heart, Blood and Endocrinology Centre, Saint Petersburg, 3Department 65 Competitive System Analysis, National Research Nuclear University, Moscow, 4Cardiology Research Center, Moscow, Russia Abstract: The pulse wave velocity (PWV threshold for hypertensive target organ damage is presently set at 10 meters per second. New 24-hour monitors (eg, BPLab® and Vasotens® provide several PWV measurements over a period of 24–72 hours. A new parameter, ie, the Pulse Time Index of Norm (PTIN, can be calculated from these data. The PTIN is defined as the percentage of a 24-hour period during which the PWV does not exceed 10 meters per second. The aim of the present study was to test the new PTIN for clinical feasibility using day-to-day repeatability analysis. Oscillometrically generated waveform files (n=85, which were previously used for research studies, were reanalyzed using the new 2013 version software of the Vasotens technology program, which enables calculation of PTIN. The intraclass correlation coefficient was 0.98 and Cronbach's alpha was 0.97, indicating that the PTIN has excellent day-to-day repeatability and internal consistency. The present results show adequate repeatability, and PTIN assessment using the Vasotens technology appears to be feasible. Keywords: pulse wave velocity, ambulatory, 24-hour, monitoring, Pulse Time Index of Norm, arterial stiffness

  4. Sex differences in behavioral and PKA cascade responses to repeated cocaine administration.

    Science.gov (United States)

    Zhou, Luyi; Sun, Wei-Lun; Weierstall, Karen; Minerly, Ana Christina; Weiner, Jan; Jenab, Shirzad; Quinones-Jenab, Vanya

    2016-10-01

    Previous studies have shown sex different patterns in behavioral responses to cocaine. Here, we used between-subject experiment design to study whether sex differences exist in the development of behavioral sensitization and tolerance to repeated cocaine, as well as the role of protein kinase A (PKA) signaling cascade in this process. Ambulatory and rearing responses were recorded in male and female rats after 1 to 14 days of administration of saline or cocaine (15 mg/kg; ip). Correspondent PKA-associated signaling in the nucleus accumbens (NAc) and caudate-putamen (CPu) was measured at each time point. Our results showed that females exhibited higher cocaine-induced behavioral responses and developed behavioral sensitization and tolerance faster than males. Whereas females developed behavioral sensitization to cocaine after 2 days and tolerance after 14 days, male rats developed sensitization after 5 days. In addition, cocaine induced a sexual dimorphic pattern in the progression of neuronal adaptations on the PKA cascade signaling in region (NAc vs. CPu) and time (days of cocaine administration)-dependent manners. In general, more PKA signaling cascade changes were found in the NAc of males on day 5 and in the CPu of females with repeated cocaine injection. In addition, in females, behavioral activities positively correlated with FosB levels in the NAc and CPu and negatively correlated with Cdk5 and p35 in the CPu, while no correlation was observed in males. Our studies suggest that repeated cocaine administration induced different patterns of behavioral and molecular responses in the PKA cascade in male and female rats.

  5. Test–retest reliability and repeatability of renal diffusion tensor MRI in healthy subjects

    International Nuclear Information System (INIS)

    Cutajar, Marica; Clayden, Jonathan D.; Clark, Christopher A.; Gordon, Isky

    2011-01-01

    Purpose: This study assessed test–retest reliability and repeatability of diffusion tensor imaging (DTI) in the kidneys. Materials and methods: Seven healthy volunteers (age range, 19–31 years), were imaged three consecutive times on the same day (short-term reliability) and the same imaging protocol was repeated after a month (long-term reliability). Diffusion-weighted magnetic resonance imaging scans in the coronal-oblique projection of the kidney were acquired on a 1.5 T scanner using a multi-section echo-planar sequence; six contiguous slices each 5 mm thick, diffusion sensitisation along 20 non-collinear directions, TR = 730 ms, TE = 73 ms and 2 b-values (0 and 400 s mm −2 ). Volunteers were asked to hold their breath throughout each data acquisition (approx. 20 s). The apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were obtained from maps generated using dedicated software MIStar (Apollo Medical Imaging, Melbourne, Australia). Results: Statistical analyses of both short- and long-term repeats were carried out from which the within-subject coefficient of variation (wsCV) was calculated. The wsCV obtained for both the ADC and FA values were less than 10% in all the analyses carried out. In addition, paired (repeated measures) t-test was used to measure the variation between the diffusion parameters collected from the two scanning sessions a month apart. It showed no significant difference and the wsCV obtained after comparing the first and second scans were found to be smaller than 15% for both ADC and FA. Conclusion: Renal DTI produces reliable and repeatable results which make longitudinal investigation of patients viable.

  6. Two-dimensional quantum repeaters

    Science.gov (United States)

    Wallnöfer, J.; Zwerger, M.; Muschik, C.; Sangouard, N.; Dür, W.

    2016-11-01

    The endeavor to develop quantum networks gave rise to a rapidly developing field with far-reaching applications such as secure communication and the realization of distributed computing tasks. This ultimately calls for the creation of flexible multiuser structures that allow for quantum communication between arbitrary pairs of parties in the network and facilitate also multiuser applications. To address this challenge, we propose a two-dimensional quantum repeater architecture to establish long-distance entanglement shared between multiple communication partners in the presence of channel noise and imperfect local control operations. The scheme is based on the creation of self-similar multiqubit entanglement structures at growing scale, where variants of entanglement swapping and multiparty entanglement purification are combined to create high-fidelity entangled states. We show how such networks can be implemented using trapped ions in cavities.

  7. Breaks in the 45S rDNA Lead to Recombination-Mediated Loss of Repeats.

    Science.gov (United States)

    Warmerdam, Daniël O; van den Berg, Jeroen; Medema, René H

    2016-03-22

    rDNA repeats constitute the most heavily transcribed region in the human genome. Tumors frequently display elevated levels of recombination in rDNA, indicating that the repeats are a liability to the genomic integrity of a cell. However, little is known about how cells deal with DNA double-stranded breaks in rDNA. Using selective endonucleases, we show that human cells are highly sensitive to breaks in 45S but not the 5S rDNA repeats. We find that homologous recombination inhibits repair of breaks in 45S rDNA, and this results in repeat loss. We identify the structural maintenance of chromosomes protein 5 (SMC5) as contributing to recombination-mediated repair of rDNA breaks. Together, our data demonstrate that SMC5-mediated recombination can lead to error-prone repair of 45S rDNA repeats, resulting in their loss and thereby reducing cellular viability. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  8. The effect of sex on the repeatability of evolution in different environments.

    Science.gov (United States)

    Lachapelle, Josianne; Colegrave, Nick

    2017-04-01

    The adaptive function of sex has been extensively studied, while less consideration has been given to the potential downstream consequences of sex on evolution. Here, we investigate one such potential consequence, the effect of sex on the repeatability of evolution. By affecting the repeatability of evolution, sex could have important implications for biodiversity, and for our ability to make predictions about the outcome of environmental change. We allowed asexual and sexual populations of Chlamydomonas reinhardtii to evolve in novel environments and monitored both their change in fitness and variance in fitness after evolution. Sex affected the repeatability of evolution by changing the importance of the effect of selection, chance, and ancestral constraints on the outcome of the evolutionary process. In particular, the effects of sex were highly dependent on the initial genetic composition of the population and on the environment. Given the lack of a consistent effect of sex on repeatability across the environments used here, further studies to dissect in more detail the underlying reasons for these differences as well as studies in additional environments are required if we are to have a general understanding of the effects of sex on the repeatability of evolution. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  9. Preservice science teachers' experiences with repeated, guided inquiry

    Science.gov (United States)

    Slack, Amy B.

    The purpose of this study was to examine preservice science teachers' experiences with repeated scientific inquiry (SI) activities. The National Science Education Standards (National Research Council, 1996) stress students should understand and possess the abilities to do SI. For students to meet these standards, science teachers must understand and be able to perform SI; however, previous research demonstrated that many teachers have naive understandings in this area. Teacher preparation programs provide an opportunity to facilitate the development of inquiry understandings and abilities. In this study, preservice science teachers had experiences with two inquiry activities that were repeated three times each. The research questions for this study were (a) How do preservice science teachers' describe their experiences with repeated, guided inquiry activities? (b) What are preservice science teachers' understandings and abilities of SI? This study was conducted at a large, urban university in the southeastern United States. The 5 participants had bachelor's degrees in science and were enrolled in a graduate science education methods course. The researcher was one of the course instructors but did not lead the activities. Case study methodology was used. Data was collected from a demographic survey, an open-ended questionnaire with follow-up interviews, the researcher's observations, participants' lab notes, personal interviews, and participants' journals. Data were coded and analyzed through chronological data matrices to identify patterns in participants' experiences. The five domains identified in this study were understandings of SI, abilities to conduct SI, personal feelings about the experience, science content knowledge, and classroom implications. Through analysis of themes identified within each domain, the four conclusions made about these preservice teachers' experiences with SI were that the experience increased their abilities to conduct inquiry

  10. Repeated prenatal exposure to valproic acid results in cerebellar hypoplasia and ataxia.

    Science.gov (United States)

    Main, Stacey L; Kulesza, Randy J

    2017-01-06

    Autism spectrum disorder (ASD) is a developmental brain disorder characterized by restricted and repetitive patterns of behavior, social and communication defects, and is commonly associated with difficulties with motor coordination. The etiology of ASD, while mostly idiopathic, has been linked to hereditary factors and teratogens, such as valproic acid (VPA). VPA is used clinically to treat epilepsy, mood disorders, and in the prevention of migraines. The use of VPA during pregnancy significantly increases the risk of ASD in the offspring. Neuropathological studies show decreased cerebellar function in patients with ASD, resulting in gait, balance and coordination impairments. Herein, we have exposed pregnant rats to a repeated oral dose of VPA on embryonic days 10 and 12 and performed a detailed investigation of the structure and function of the cerebellar vermis. We found that throughout all ten lobules of the cerebellar vermis, Purkinje cells were significantly smaller and expression of the calcium binding protein calbindin (CB) was significantly reduced. We also found that dendritic arbors of Purkinje cells were shorter and less complex. Additionally, animals exposed to a repeated dose of VPA performed significantly worse in a number of motor tasks, including beam walking and the rotarod. These results suggest that repeated embryonic exposure to VPA induces significant cerebellar dysfunction and is an effective animal model to study the cerebellar alterations in ASD. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  11. REPEATABILITY OF THE FRENCH HIGHER VEGETATION TYPES ACCORDING

    Directory of Open Access Journals (Sweden)

    H. BRISSE

    1998-04-01

    Full Text Available Higher vegetation types are generally determined by successive approximations and defined by a common consent. Instead, they might be statistically determined and repeated, according to a numerical method called ‘socio-ecology’. This method deals only with floristical data, but gives them an ecological meaning by a previous calibration of the relations between plants, computed as ecological indices. It is applied to a pair of two homologous samples, each having 2.000 relevés and coming from the 60.000 relevés stored in the French data bank ‘Sophy’. Each sample covers the main ecological gradients of the bank, it defines a hierarchy of vegetation types and it explains half the peculiarity of a type with only 10 to 30 discriminant plants, out of the 5.000 plants observed in the relevés. Results : 1 The discriminant plants may characterize the vegetation types, including the higher ones, in a coherent and readable form. 2 In the two independent classifications, having different structures, the same vegetation types are repeated. They are the reciprocal nearest types, in the socio-ecological space. Though the two classifications have no one relevé in common, the repeated types have nearly the same discriminant plants. 3 At the highest level, two clear-cut main types show the difference between light and shadow. The same herbaceous discriminant plants, for a type, and the ligneous or sciaphilous ones, for the other, have similar fidelities and constancies in the two classifications. 4 Such a numerical agreement, instead of common consent, appears again in the sub-types, which remind the classical ones, but which are repeatable.

  12. Beyond Extinction: Prolonged Conditioning and Repeated Threat Exposure Abolish Contextual Renewal of Fear-Potentiated Startle Discrimination but Leave Expectancy Ratings Intact.

    Science.gov (United States)

    Leer, Arne; Haesen, Kim; Vervliet, Bram

    2018-01-01

    Extinction treatments decrease fear via repeated exposures to the conditioned stimulus (CS) and are associated with a return of fear. Alternatively, fear can be reduced via reductions in the perceived intensity of the unconditioned stimulus (US), e.g., through repeated exposures to the US. Promisingly, the few available studies show that repeated US exposures outperform standard extinction. US exposure treatments can decrease fear via two routes: (1) by weakening the CS-US association (extinction-like mechanism), and/or (2) by weakening the subjective US aversiveness (habituation-like mechanism). The current study further investigated the conditions under which US exposure treatment may reduce renewal, by adding a group in which CS-US pairings continued following fear acquisition. During acquisition, participants learned that one of two visual stimuli (CS+/CS-) predicted the occurrence of an aversive electrocutaneous stimulus (US). Next, the background context changed and participants received one of three interventions: repeated CS exposures, (2) repeated US exposures, or (3) continued CS-US pairings. Following repeated CS exposures, test presentations of the CSs in the original conditioning context revealed intact CS+/CS- differentiation in the fear-potentiated startle reflex, while the differentiation was abolished in the other two groups. Differential US expectancy ratings, on the other hand, were intact in all groups. Skin conductance data were inconclusive because standard context renewal following CS exposures did not occur. Unexpectedly, there was no evidence for a habituation-like process having taken place during US exposures or continued CS-US pairings. The results provide further evidence that US exposures outperform the standard extinction treatment and show that effects are similar when US exposures are part of CS-US pairings.

  13. Conservative Sample Size Determination for Repeated Measures Analysis of Covariance.

    Science.gov (United States)

    Morgan, Timothy M; Case, L Douglas

    2013-07-05

    In the design of a randomized clinical trial with one pre and multiple post randomized assessments of the outcome variable, one needs to account for the repeated measures in determining the appropriate sample size. Unfortunately, one seldom has a good estimate of the variance of the outcome measure, let alone the correlations among the measurements over time. We show how sample sizes can be calculated by making conservative assumptions regarding the correlations for a variety of covariance structures. The most conservative choice for the correlation depends on the covariance structure and the number of repeated measures. In the absence of good estimates of the correlations, the sample size is often based on a two-sample t-test, making the 'ultra' conservative and unrealistic assumption that there are zero correlations between the baseline and follow-up measures while at the same time assuming there are perfect correlations between the follow-up measures. Compared to the case of taking a single measurement, substantial savings in sample size can be realized by accounting for the repeated measures, even with very conservative assumptions regarding the parameters of the assumed correlation matrix. Assuming compound symmetry, the sample size from the two-sample t-test calculation can be reduced at least 44%, 56%, and 61% for repeated measures analysis of covariance by taking 2, 3, and 4 follow-up measures, respectively. The results offer a rational basis for determining a fairly conservative, yet efficient, sample size for clinical trials with repeated measures and a baseline value.

  14. Improving the repeatability of Motor Unit Number Index (MUNIX) by introducing additional epochs at low contraction levels.

    Science.gov (United States)

    Peng, Yun; Zhang, Yingchun

    2017-07-01

    To evaluate the repeatability of (Motor Unit Number Index) MUNIX under repeatability conditions, specify the origin of variations and provide strategies for quality control. MUNIX calculations were performed on the bicep brachii muscles of eight healthy subjects. Negative effect of suboptimal electrode positions on MUNIX accuracy was eliminated by employing the high-density surface electromyography technique. MUNIX procedures that utilized a variety of surface interferential pattern (SIP) epoch recruitment strategies (including the original MUNIX procedure, two proposed improvement strategies and their combinations) were described. For each MUNIX procedure, ten thousands of different SIP pools were constructed by randomly recruiting necessary SIP epochs from a large SIP epoch pool (3 datasets, 9 independent electromyography recordings at different contraction levels per dataset and 10 SIP epochs per recording) and implemented for MUNIX calculation. The repeatability of each MUNIX procedure was assessed by summarizing the resulting MUNIX distribution and compared to investigate the effect of SIP epoch selection strategy on repeatability performance. SIP epochs selected at lower contraction levels have a stronger influence on the repeatability of MUNIX than those selected at higher contraction levels. MUNIX under repeatability conditions follows a normal distribution and the standard deviation can be significantly reduced by introducing more epochs near the MUNIX definition line. The MUNIX technique shows an inherent variation attributable to SIP epochs at low contraction levels. It is recommended that more epochs should be sampled at these low contraction levels to improve the repeatability. The present study thoroughly documented the inherent variation of MUNIX and the causes, and offered practical solutions to improve the repeatability of MUNIX. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  15. Complexity of repeated game model in electric power triopoly

    International Nuclear Information System (INIS)

    Ma Junhai; Ji Weizhuo

    2009-01-01

    According to the repeated game model in electric power duopoly, a triopoly outputs game model is presented. On the basis of some hypotheses, the dynamic characters are demonstrated with theoretical analysis and numerical simulations. The results show that the triopoly model is a chaotic system and it is better than the duopoly model in applications.

  16. Study of the repeatability of histone genes in the ploidy series of wheat and Aegilops

    International Nuclear Information System (INIS)

    Vakhitov, V.A.; Kulikov, A.M.

    1986-01-01

    The hDNA content and number of histone genes in the genomes of different wheat and Aegilops species have been determined by molecular hybridization of DNA with 125 I-histone DNA of Drosophila (L-repeat) on nitrocellulose filters. It has been demonstrated that the proportion of hDNA in the total DNA of diploid and polyploid wheat species is (1.3-7.7) x 10 -3 % (57-850 genes), and in the ploidy series of Aegilops species (2.0-8.0) x 10 -3 % (89-780 genes). The repeatability of the histone genes generally increases at each ploidy level in the species with higher DNA content. At the same time, it has been demonstrated that the DNA content is not the only factor determining repeatability of the histone genes, as some diploid and allopolyploid species have similar number of these genes. It has been concluded that genetic mechanisms are involved in the regulation of the number of histone genes

  17. Differential interaction and aggregation of 3-repeat and 4-repeat tau isoforms with 14-3-3ζ protein

    International Nuclear Information System (INIS)

    Sadik, Golam; Tanaka, Toshihisa; Kato, Kiyoko; Yanagi, Kentaro; Kudo, Takashi; Takeda, Masatoshi

    2009-01-01

    Tau isoforms, 3-repeat (3R) and 4-repeat tau (4R), are differentially involved in neuronal development and in several tauopathies. 14-3-3 protein binds to tau and 14-3-3/tau association has been found both in the development and in tauopathies. To understand the role of 14-3-3 in the differential regulation of tau isoforms, we have performed studies on the interaction and aggregation of 3R-tau and 4R-tau, either phosphorylated or unphosphorylated, with 14-3-3ζ. We show by surface plasmon resonance studies that the interaction between unphosphorylated 3R-tau and 14-3-3ζ is ∼3-folds higher than that between unphosphorylated 4R-tau and 14-3-3ζ. Phosphorylation of tau by protein kinase A (PKA) increases the affinity of both 3R- and 4R-tau for 14-3-3ζ to a similar level. An in vitro aggregation assay employing both transmission electron microscopy and fluorescence spectroscopy revealed the aggregation of unphosphorylated 4R-tau to be significantly higher than that of unphosphorylated 3R-tau following the induction of 14-3-3ζ. The filaments formed from 3R- and 4R-tau were almost similar in morphology. In contrast, the aggregation of both 3R- and 4R-tau was reduced to a similar low level after phosphorylation with PKA. Taken together, these results suggest that 14-3-3ζ exhibits a similar role for tau isoforms after PKA-phosphorylation, but a differential role for unphosphorylated tau. The significant aggregation of 4R-tau by 14-3-3ζ suggests that 14-3-3 may act as an inducer in the generation of 4R-tau-predominant neurofibrillary tangles in tauopathies.

  18. Repeatability of quantitative sensory testing in healthy cats in a clinical setting with comparison to cats with osteoarthritis.

    Science.gov (United States)

    Addison, Elena S; Clements, Dylan N

    2017-12-01

    Objectives The aim of this study was to evaluate the repeatability of quantitative sensory tests (QSTs) in a group of healthy untrained cats (n = 14) and to compare the results with those from cats with osteoarthritis (n = 7). Methods Peak vertical force (PVF) and vertical impulse were measured on a pressure plate system. Thermal sensitivity was assessed using a temperature-controlled plate at 7°C and 40°C. Individual paw lifts and overall duration of paw lifts were counted and measured for each limb. Paw withdrawal thresholds were measured using manual and electronic von Frey monofilaments (MVF and EVF, respectively) applied to the metacarpal or metatarsal pads. All measurements were repeated twice to assess repeatability of the tests. Results In healthy cats all tests were moderately repeatable. When compared with cats with osteoarthritis the PVF was significantly higher in healthy hindlimbs in repeat 1 but not in repeat 2. Cats with osteoarthritis of the forelimbs showed a decrease in the frequency of paw lifts on the 7°C plate compared with cats with healthy forelimbs, and the duration of paw lifts was significantly less than healthy forelimbs in the first repeat but not in the second repeat. Osteoarthritic limbs had significantly lower paw withdrawal thresholds with both MVF and EVF than healthy limbs. Conclusions and relevance QSTs are moderately repeatable in untrained cats. Kinetic gait analysis did not permit differentiation between healthy limbs and those with osteoarthritis, but thermal sensitivity testing (cold) does. Sensory threshold testing can differentiate osteoarthritic and healthy limbs, and may be useful in the diagnosis and monitoring of this condition in cats in the clinical setting.

  19. The impact of repeat-testing of common chemistry analytes at critical concentrations.

    Science.gov (United States)

    Onyenekwu, Chinelo P; Hudson, Careen L; Zemlin, Annalise E; Erasmus, Rajiv T

    2014-12-01

    Early notification of critical values by the clinical laboratory to the treating physician is a requirement for accreditation and is essential for effective patient management. Many laboratories automatically repeat a critical value before reporting it to prevent possible misdiagnosis. Given today's advanced instrumentation and quality assurance practices, we questioned the validity of this approach. We performed an audit of repeat-testing in our laboratory to assess for significant differences between initial and repeated test results, estimate the delay caused by repeat-testing and to quantify the cost of repeating these assays. A retrospective audit of repeat-tests for sodium, potassium, calcium and magnesium in the first quarter of 2013 at Tygerberg Academic Laboratory was conducted. Data on the initial and repeat-test values and the time that they were performed was extracted from our laboratory information system. The Clinical Laboratory Improvement Amendment criteria for allowable error were employed to assess for significant difference between results. A total of 2308 repeated tests were studied. There was no significant difference in 2291 (99.3%) of the samples. The average delay ranged from 35 min for magnesium to 42 min for sodium and calcium. At least 2.9% of laboratory running costs for the analytes was spent on repeating them. The practice of repeating a critical test result appears unnecessary as it yields similar results, delays notification to the treating clinician and increases laboratory running costs.

  20. Ups and Downs: Mechanisms of Repeat Instability in the Fragile X-Related Disorders

    Directory of Open Access Journals (Sweden)

    Xiao-Nan Zhao

    2016-09-01

    Full Text Available The Fragile X-related disorders (FXDs are a group of clinical conditions resulting from the expansion of a CGG/CCG-repeat tract in exon 1 of the Fragile X mental retardation 1 (FMR1 gene. While expansions of the repeat tract predominate, contractions are also seen with the net result being that individuals can show extensive repeat length heterogeneity in different tissues. The mechanisms responsible for expansion and contraction are still not well understood. This review will discuss what is known about these processes and current evidence that supports a model in which expansion arises from the interaction of components of the base excision repair, mismatch repair and transcription coupled repair pathways.

  1. Repeated Gene Transfection Impairs the Engraftment of Transplanted Porcine Neonatal Pancreatic Cells

    Directory of Open Access Journals (Sweden)

    Min Koo Seo

    2011-02-01

    Full Text Available BackgroundPreviously, we reported that neonatal porcine pancreatic cells transfected with hepatocyte growth factor (HGF gene in an Epstein-Barr virus (EBV-based plasmid (pEBVHGF showed improved proliferation and differentiation compared to those of the control. In this study, we examined if pancreatic cells transfected repeatedly with pEBVHGF can be successfully grafted to control blood glucose in a diabetes mouse model.MethodsNeonatal porcine pancreatic cells were cultured as a monolayer and were transfected with pEBVHGF every other day for a total of three transfections. The transfected pancreatic cells were re-aggregated and transplanted into kidney capsules of diabetic nude mice or normal nude mice. Blood glucose level and body weight were measured every other day after transplantation. The engraftment of the transplanted cells and differentiation into beta cells were assessed using immunohistochemistry.ResultsRe-aggregation of the pancreatic cells before transplantation improved engraftment of the cells and facilitated neovascularization of the graft. Right before transplantation, pancreatic cells that were transfected with pEBVHGF and then re-aggregated showed ductal cell marker expression. However, ductal cells disappeared and the cells underwent fibrosis in a diabetes mouse model two to five weeks after transplantation; these mice also did not show controlled blood glucose levels. Furthermore, pancreatic cells transplanted into nude mice with normal blood glucose showed poor graft survival regardless of the type of transfected plasmid (pCEP4, pHGF, or pEBVHGF.ConclusionFor clinical application of transfected neonatal porcine pancreatic cells, further studies are required to develop methods of overcoming the damage for the cells caused by repeated transfection and to re-aggregate them into islet-like structures.

  2. Repeated exposure to cat urine induces complex behavioral, hormonal, and c-fos mRNA responses in Norway rats ( Rattus norvegicus)

    Science.gov (United States)

    Yin, Baofa; Gu, Chen; Lu, Yi; Hegab, Ibrahim M.; Yang, Shengmei; Wang, Aiqin; Wei, Wanhong

    2017-08-01

    Prey species show specific adaptations that allow recognition, avoidance, and defense against predators. This study was undertaken to investigate the processing of a chronic, life-threatening stimulus to Norway rats ( Rattus norvegicus). One hundred forty-four Norway rats were tested by repeated presentation of cat urine for 1 h at different days in a defensive withdrawal apparatus. Rats exposed to urine for short periods showed significantly larger defensive behavioral and medial hypothalamic c-fos messenger RNA (mRNA) responses than other groups. These defensive responses habituated shortly after the presentation of cat urine. Serum levels of adrenocorticotropic hormone and corticosterone increased significantly when animals were repeatedly exposed to cat urine. However, the hormonal responses took longer to habituate than the behavioral and molecular responses did. We conclude that the behavioral and c-fos mRNA responses are "primed" for habituation to repeated exposures to cat urine, while the hormonal responses show "resistance." The results support our hypothesis that the strongest anti-predator responses at three levels would occur during short-term exposure to cat urine and that these responses would subsequently disappear on prolonged exposure. This study assists understanding the way in which the different levels of defensive responses are integrated and react during chronic stress.

  3. Is MR imaging useful for detecting prostate cancer in cases requiring repeat biopsy?. Presidential award proceedings

    International Nuclear Information System (INIS)

    Ito, Hirotoshi; Takahata, Akiko; Goto, Mariko; Masunami, Terutoshi; Yuen, Sachiko; Yamada, Kei; Nishimura, Tsunehiko

    2007-01-01

    The purpose of this study was to evaluate the usefulness of magnetic resonance (MR) imaging in detecting prostate cancer in cases requiring repeat biopsy. Twenty patients with negative first prostate biopsy were evaluated by T2-weighted images (T 2 W), diffusion weighted image (DWI), and contrast-enhanced dynamic MRI at 1.5T prior to repeat biopsy. Eleven of the 20 also underwent MR imaging before initial biopsy. Cancer criteria were defined as an area of low signal intensity on T 2 W, high signal intensity on DWI, and early enhancement on dynamic MR imaging. We compared MR imaging findings with biopsy results. Prostate cancer was detected by repeat biopsy in nine of 20 patients. MR imaging demonstrated the cancer lesion in seven of the 9 patients whose biopsies were positive for cancer. MR imaging of 5 patients whose biopsies showed cancer also demonstrated cancer lesion previous to initial biopsy. Most cancers were detected in the anterior, apex, and far lateral areas. False-negative cases were low-grade cancers and had a few positive biopsy cores. In patients with repeat prostate biopsy, prior MR imaging may be valuable for detecting and localizing prostate cancer. (author)

  4. Device-independent secret-key-rate analysis for quantum repeaters

    Science.gov (United States)

    Holz, Timo; Kampermann, Hermann; Bruß, Dagmar

    2018-01-01

    The device-independent approach to quantum key distribution (QKD) aims to establish a secret key between two or more parties with untrusted devices, potentially under full control of a quantum adversary. The performance of a QKD protocol can be quantified by the secret key rate, which can be lower bounded via the violation of an appropriate Bell inequality in a setup with untrusted devices. We study secret key rates in the device-independent scenario for different quantum repeater setups and compare them to their device-dependent analogon. The quantum repeater setups under consideration are the original protocol by Briegel et al. [Phys. Rev. Lett. 81, 5932 (1998), 10.1103/PhysRevLett.81.5932] and the hybrid quantum repeater protocol by van Loock et al. [Phys. Rev. Lett. 96, 240501 (2006), 10.1103/PhysRevLett.96.240501]. For a given repeater scheme and a given QKD protocol, the secret key rate depends on a variety of parameters, such as the gate quality or the detector efficiency. We systematically analyze the impact of these parameters and suggest optimized strategies.

  5. Coexistence of 3G repeaters with LTE base stations.

    Science.gov (United States)

    Yeo, Woon-Young; Lee, Sang-Min; Hwang, Gyung-Ho; Kim, Jae-Hoon

    2013-01-01

    Repeaters have been an attractive solution for mobile operators to upgrade their wireless networks at low cost and to extend network coverage effectively. Since the first LTE commercial deployment in 2009, many mobile operators have launched LTE networks by upgrading their 3G and legacy networks. Because all 3G frequency bands are shared with the frequency bands for LTE deployment and 3G mobile operators have an enormous number of repeaters, reusing 3G repeaters in LTE networks is definitely a practical and cost-efficient solution. However, 3G repeaters usually do not support spatial multiplexing with multiple antennas, and thus it is difficult to reuse them directly in LTE networks. In order to support spatial multiplexing of LTE, the role of 3G repeaters should be replaced with small LTE base stations or MIMO-capable repeaters. In this paper, a repeater network is proposed to reuse 3G repeaters in LTE deployment while still supporting multilayer transmission of LTE. Interestingly, the proposed network has a higher cluster throughput than an LTE network with MIMO-capable repeaters.

  6. Repeatability & Workability Evaluation of SIGMOD 2009

    KAUST Repository

    Manegold, Stefan

    2010-12-15

    SIGMOD 2008 was the first database conference that offered to test submitters\\' programs against their data to verify the repeatability of the experiments published [1]. Given the positive feedback concerning the SIGMOD 2008 repeatability initiative, SIGMOD 2009 modified and expanded the initiative with a workability assessment.

  7. Repeatability & Workability Evaluation of SIGMOD 2009

    KAUST Repository

    Manegold, Stefan; Manolescu, Ioana; Afanasiev, Loredana; Feng, Jieling; Gou, G.; Hadjieleftheriou, Marios; Harizopoulos, Stavros; Kalnis, Panos; Karanasos, Konstantinos; Laurent, Dominique; Lupu, M.; Onose, N.; Ré , C.; Sans, Virginie; Senellart, Pierre; Wu, T.; Shasha, Dennis E.

    2010-01-01

    SIGMOD 2008 was the first database conference that offered to test submitters' programs against their data to verify the repeatability of the experiments published [1]. Given the positive feedback concerning the SIGMOD 2008 repeatability initiative, SIGMOD 2009 modified and expanded the initiative with a workability assessment.

  8. Comparing Destination Image and Loyalty between First-time and Repeat-visit Tourists

    Directory of Open Access Journals (Sweden)

    Mohamad M.

    2014-01-01

    Full Text Available The objective of this study was to investigate the difference between destination image and loyalty among first-time and repeat-visit tourists. The study was undertaken to examine aspects of underlying factors of destination image that influenced tourists’ willingness to recommend Malaysia to their friends and relatives as well as spread positive word-of-mouth to others. In addition, it was to ascertain the relationship between destination image and loyalty among first-time and repeat-visit tourists. The data was collected at Kuala Lumpur International Airport at the departure hall using self-administered questionnaires. 248 usable questionnaires were returned and analysed. The findings of the study revealed that both groups of tourists perceived Malaysia as providing a nature-based destination. The study also empirically proved that both first-time and repeat-visit tourists were willing to disseminate positive word-of-mouth and recommend Malaysia to their friends and relatives as a vacation destination to visit. However, there was a significant difference in destination loyalty between first-visit and repeat-visit tourists.

  9. On the improvement of signal repeatability in laser-induced air plasmas

    Science.gov (United States)

    Zhang, Shuai; Sheta, Sahar; Hou, Zong-Yu; Wang, Zhe

    2018-04-01

    The relatively low repeatability of laser-induced breakdown spectroscopy (LIBS) severely hinders its wide commercialization. In the present work, we investigate the optimization of LIBS system for repeatability improvement for both signal generation (plasma evolution) and signal collection. Timeintegrated spectra and images were obtained under different laser energies and focal lengths to investigate the optimum configuration for stable plasmas and repeatable signals. Using our experimental setup, the optimum conditions were found to be a laser energy of 250 mJ and a focus length of 100 mm. A stable and homogeneous plasma with the largest hot core area in the optimum condition yielded the most stable LIBS signal. Time-resolved images showed that the rebounding processes through the air plasma evolution caused the relative standard deviation (RSD) to increase with laser energies of > 250 mJ. In addition, the emission collection was improved by using a concave spherical mirror. The line intensities doubled as their RSDs decreased by approximately 25%. When the signal generation and collection were optimized simultaneously, the pulse-to-pulse RSDs were reduced to approximately 3% for O(I), N(I), and H(I) lines, which are better than the RSDs reported for solid samples and showed great potential for LIBS quantitative analysis by gasifying the solid or liquid samples.

  10. Kinematic repeatability of a multi-segment foot model for dance.

    Science.gov (United States)

    Carter, Sarah L; Sato, Nahoko; Hopper, Luke S

    2018-03-01

    The purpose of this study was to determine the intra and inter-assessor repeatability of a modified Rizzoli Foot Model for analysing the foot kinematics of ballet dancers. Six university-level ballet dancers performed the movements; parallel stance, turnout plié, turnout stance, turnout rise and flex-point-flex. The three-dimensional (3D) position of individual reflective markers and marker triads was used to model the movement of the dancers' tibia, entire foot, hindfoot, midfoot, forefoot and hallux. Intra and inter-assessor reliability demonstrated excellent (ICC ≥ 0.75) repeatability for the first metatarsophalangeal joint in the sagittal plane. Intra-assessor reliability demonstrated excellent (ICC ≥ 0.75) repeatability during flex-point-flex across all inter-segmental angles except for the tibia-hindfoot and hindfoot-midfoot frontal planes. Inter-assessor repeatability ranged from poor to excellent (0.5 > ICC ≥ 0.75) for the 3D segment rotations. The most repeatable measure was the tibia-foot dorsiflexion/plantar flexion articulation whereas the least repeatable measure was the hindfoot-midfoot adduction/abduction articulation. The variation found in the inter-assessor results is likely due to inconsistencies in marker placement. This 3D dance specific multi-segment foot model provides insight into which kinematic measures can be reliably used to ascertain in vivo technical errors and/or biomechanical abnormalities in a dancer's foot motion.

  11. The use of a measure of acute irritation to predict the outcome of repeated usage of hand soap products.

    Science.gov (United States)

    Williams, C; Wilkinson, M; McShane, P; Pennington, D; Fernandez, C; Pierce, S

    2011-06-01

    worsening of skin barrier function. This effect was also seen initially for product D at day 7 although this was then lost at day 14. Further regression analysis was then performed to see if the acute irritant test data for each product correlated with the skin barrier data from the repeated usage component of the study. This showed that the results of acute irritant testing of the individual products did not predict the results of chronic use of hand soaps. The results from phase 2 of our study confirm the work of previous studies that show that regular exposure to irritants in daily life leads to stratum corneum damage and impairment of the skin barrier. Although significant differences were seen between the products in phase 1 of the study, regression analysis showed that the results of patch testing of the individual products did not predict the results of chronic use of hand soaps. When designing a study to assess the effects of cumulative use of a product on the skin, the study should mirror the use conditions of the product as closely as possible. © 2011 The Authors. BJD © 2011 British Association of Dermatologists.

  12. Prostate cancer detection rate in patients with fluctuating prostate-specific antigen levels on the repeat prostate biopsy

    Directory of Open Access Journals (Sweden)

    Yong Hyun Park

    2014-03-01

    Conclusions: The current study shows that the risk of prostate cancer at repeat TRUS-Bx was higher in men with a fluctuating PSA level and PSAV=1.0 ng/mL/yr than in those with a fluctuating PSA level and PSAV<1.0 ng/mL/yr.

  13. SU-E-J-263: Repeatability of SUV and Texture Parameters in Serial PET Studies

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, J; Humm, J; Nehmeh, S; Schoder, H [Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2015-06-15

    Purpose: Standardized uptake values (SUV) are standard quantitative PET measures of FDG tumor uptake used,and are used as a tool to monitor response to therapy. Textural analysis is emerging as a new tool for assessing intratumoral heterogeneity which may allow better tissue characterization and improved prediction of response and survival rate.Understanding what variations may be expected in these parameters is key in order to make decisions based on how the change throughout the course of treatment. The aim of this study was to assess repeatability in SUV measures and texture parameters,and establish criteria that differentiate changes associated with treatment rather than statistical variability. Methods: Eighty patients,167 random lesions total,were scanned in a GE Discovery STE PET/CT Scanner. One field-of-view was chosen centered on the largest lesion observed in a clinical whole-body FDG PET.Immediately following,a gated 9 min scan was acquired in list mode,without changing the patient’s position between any scans. Data was replayed into 3 time bins,3 min each,in order to insure equivalent noise characteristics in each replicate.Data was reconstructed into 128×128×47 square matrices.One VOI was drawn over each lesion for each patient and used to segment all 3 replicates. The mean.max and peak SUV were calculated for each VOI and replicate. First-order textural features were also calculated (skewness and kurtosis). Repeatability was calculated as the average standard deviation over the mean for the 3 repeated measurements for each lesion. Results: The average percent error in the SUV max,peak and mean were 3.4%(0– 12.9%),1.9% (0–7.5%),2.8% (0–12.2%),respectively.For skewness and kurtosis they were 10.9% and 17.8%. Conclusion: We have shown that there is a large variation in %error in SUV measures across patients. SUVpeak is the least variable and kurtosis and skewness parameters are less reliable thatn SUVs.Higher order textures are be.

  14. SU-E-J-263: Repeatability of SUV and Texture Parameters in Serial PET Studies

    International Nuclear Information System (INIS)

    Schwartz, J; Humm, J; Nehmeh, S; Schoder, H

    2015-01-01

    Purpose: Standardized uptake values (SUV) are standard quantitative PET measures of FDG tumor uptake used,and are used as a tool to monitor response to therapy. Textural analysis is emerging as a new tool for assessing intratumoral heterogeneity which may allow better tissue characterization and improved prediction of response and survival rate.Understanding what variations may be expected in these parameters is key in order to make decisions based on how the change throughout the course of treatment. The aim of this study was to assess repeatability in SUV measures and texture parameters,and establish criteria that differentiate changes associated with treatment rather than statistical variability. Methods: Eighty patients,167 random lesions total,were scanned in a GE Discovery STE PET/CT Scanner. One field-of-view was chosen centered on the largest lesion observed in a clinical whole-body FDG PET.Immediately following,a gated 9 min scan was acquired in list mode,without changing the patient’s position between any scans. Data was replayed into 3 time bins,3 min each,in order to insure equivalent noise characteristics in each replicate.Data was reconstructed into 128×128×47 square matrices.One VOI was drawn over each lesion for each patient and used to segment all 3 replicates. The mean.max and peak SUV were calculated for each VOI and replicate. First-order textural features were also calculated (skewness and kurtosis). Repeatability was calculated as the average standard deviation over the mean for the 3 repeated measurements for each lesion. Results: The average percent error in the SUV max,peak and mean were 3.4%(0– 12.9%),1.9% (0–7.5%),2.8% (0–12.2%),respectively.For skewness and kurtosis they were 10.9% and 17.8%. Conclusion: We have shown that there is a large variation in %error in SUV measures across patients. SUVpeak is the least variable and kurtosis and skewness parameters are less reliable thatn SUVs.Higher order textures are be

  15. Higher Drop in Speed during a Repeated Sprint Test in Soccer Players Reporting Former Hamstring Strain Injury

    Science.gov (United States)

    Røksund, Ola D.; Kristoffersen, Morten; Bogen, Bård E.; Wisnes, Alexander; Engeseth, Merete S.; Nilsen, Ann-Kristin; Iversen, Vegard V.; Mæland, Silje; Gundersen, Hilde

    2017-01-01

    Aim: Hamstring strain injury is common in soccer. The aim of this study was to evaluate the physical capacity of players who have and have not suffered from hamstring strain injury in a sample of semi-professional and professional Norwegian soccer players in order to evaluate characteristics and to identify possible indications of insufficient rehabilitation. Method: Seventy-five semi-professional and professional soccer players (19 ± 3 years) playing at the second and third level in the Norwegian league participated in the study. All players answered a questionnaire, including one question about hamstring strain injury (yes/no) during the previous 2 years. They also performed a 40 m maximal sprint test, a repeated sprint test (8 × 20 m), a countermovement jump, a maximal oxygen consumption (VO2max) test, strength tests and flexibility tests. Independent sample t-tests were used to evaluate differences in the physical capacity of the players who had suffered from hamstring strain injury and those who had not. Mixed between-within subject's analyses of variance was used to compare changes in speed during the repeated sprint test between groups. Results: Players who reported hamstring strain injury during the previous two years (16%) had a significantly higher drop in speed (0.07 vs. 0.02 s, p = 0.007) during the repeated sprint test, compared to players reporting no previous hamstring strain injury. In addition, there was a significant interaction (groups × time) (F = 3.22, p = 0.002), showing that speed in the two groups changed differently during the repeated sprint test. There were no significant differences in relations to age, weight, height, body fat, linear speed, countermovement jump height, leg strength, VO2max, or hamstring flexibility between the groups. Conclusion: Soccer players who reported hamstring strain injury during the previous 2 years showed significant higher drop in speed during the repeated sprint test compared to players with no hamstring

  16. High precision measurement of the micro-imaging system to check repeatability of precision

    International Nuclear Information System (INIS)

    Cheng Lin; Song Li; Ma Chuntao; Luo Hongxin; Wang Jie

    2010-01-01

    The beamlines slits of Shanghai Synchrotron Radiation Facility (SSRF) are required to have a repeatability of better than 1 μm. Before the slits installation, the off-line and/or on-line repeatability measurements must be conducted. A machine vision measuring system based on high resolution CCD and adjustable high magnification lens was used in this regard. A multi-level filtering method was used to treat the imaging data. After image binarization, the imaging noises were depressed effectively by using of algebraic mean filtering, statistics median filtering,and the least square filtering. Using the subtracted image between the images before and after slit movement, an average displacement of slit blades could be obtained, and the repeatability of slit could be measured, with a resolution of 0.3 μm of the measurement system. The experimental results show that this measurement system meets the requirements for non-contact measurements to the repeatability of slits. (authors)

  17. Analysis of real-time mixture cytotoxicity data following repeated exposure using BK/TD models

    International Nuclear Information System (INIS)

    Teng, S.; Tebby, C.; Barcellini-Couget, S.; De Sousa, G.; Brochot, C.; Rahmani, R.; Pery, A.R.R.

    2016-01-01

    Cosmetic products generally consist of multiple ingredients. Thus, cosmetic risk assessment has to deal with mixture toxicity on a long-term scale which means it has to be assessed in the context of repeated exposure. Given that animal testing has been banned for cosmetics risk assessment, in vitro assays allowing long-term repeated exposure and adapted for in vitro – in vivo extrapolation need to be developed. However, most in vitro tests only assess short-term effects and consider static endpoints which hinder extrapolation to realistic human exposure scenarios where concentration in target organs is varies over time. Thanks to impedance metrics, real-time cell viability monitoring for repeated exposure has become possible. We recently constructed biokinetic/toxicodynamic models (BK/TD) to analyze such data (Teng et al., 2015) for three hepatotoxic cosmetic ingredients: coumarin, isoeugenol and benzophenone-2. In the present study, we aim to apply these models to analyze the dynamics of mixture impedance data using the concepts of concentration addition and independent action. Metabolic interactions between the mixture components were investigated, characterized and implemented in the models, as they impacted the actual cellular exposure. Indeed, cellular metabolism following mixture exposure induced a quick disappearance of the compounds from the exposure system. We showed that isoeugenol substantially decreased the metabolism of benzophenone-2, reducing the disappearance of this compound and enhancing its in vitro toxicity. Apart from this metabolic interaction, no mixtures showed any interaction, and all binary mixtures were successfully modeled by at least one model based on exposure to the individual compounds. - Highlights: • We could predict cell response over repeated exposure to mixtures of cosmetics. • Compounds acted independently on the cells. • Metabolic interactions impacted exposure concentrations to the compounds.

  18. Analysis of real-time mixture cytotoxicity data following repeated exposure using BK/TD models

    Energy Technology Data Exchange (ETDEWEB)

    Teng, S.; Tebby, C. [Models for Toxicology and Ecotoxicology Unit, INERIS, Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France); Barcellini-Couget, S. [ODESIA Neosciences, Sophia Antipolis, 400 route des chappes, 06903 Sophia Antipolis (France); De Sousa, G. [INRA, ToxAlim, 400 route des Chappes, BP, 167 06903 Sophia Antipolis, Cedex (France); Brochot, C. [Models for Toxicology and Ecotoxicology Unit, INERIS, Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France); Rahmani, R. [INRA, ToxAlim, 400 route des Chappes, BP, 167 06903 Sophia Antipolis, Cedex (France); Pery, A.R.R., E-mail: alexandre.pery@agroparistech.fr [AgroParisTech, UMR 1402 INRA-AgroParisTech Ecosys, 78850 Thiverval Grignon (France); INRA, UMR 1402 INRA-AgroParisTech Ecosys, 78850 Thiverval Grignon (France)

    2016-08-15

    Cosmetic products generally consist of multiple ingredients. Thus, cosmetic risk assessment has to deal with mixture toxicity on a long-term scale which means it has to be assessed in the context of repeated exposure. Given that animal testing has been banned for cosmetics risk assessment, in vitro assays allowing long-term repeated exposure and adapted for in vitro – in vivo extrapolation need to be developed. However, most in vitro tests only assess short-term effects and consider static endpoints which hinder extrapolation to realistic human exposure scenarios where concentration in target organs is varies over time. Thanks to impedance metrics, real-time cell viability monitoring for repeated exposure has become possible. We recently constructed biokinetic/toxicodynamic models (BK/TD) to analyze such data (Teng et al., 2015) for three hepatotoxic cosmetic ingredients: coumarin, isoeugenol and benzophenone-2. In the present study, we aim to apply these models to analyze the dynamics of mixture impedance data using the concepts of concentration addition and independent action. Metabolic interactions between the mixture components were investigated, characterized and implemented in the models, as they impacted the actual cellular exposure. Indeed, cellular metabolism following mixture exposure induced a quick disappearance of the compounds from the exposure system. We showed that isoeugenol substantially decreased the metabolism of benzophenone-2, reducing the disappearance of this compound and enhancing its in vitro toxicity. Apart from this metabolic interaction, no mixtures showed any interaction, and all binary mixtures were successfully modeled by at least one model based on exposure to the individual compounds. - Highlights: • We could predict cell response over repeated exposure to mixtures of cosmetics. • Compounds acted independently on the cells. • Metabolic interactions impacted exposure concentrations to the compounds.

  19. Chromosome-specific DNA Repeat Probes

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, Adolf; Weier, Jingly Fung; Weier, Heinz-Ulrich G.

    2006-03-16

    In research as well as in clinical applications, fluorescence in situ hybridization (FISH) has gained increasing popularity as a highly sensitive technique to study cytogenetic changes. Today, hundreds of commercially available DNA probes serve the basic needs of the biomedical research community. Widespread applications, however, are often limited by the lack of appropriately labeled, specific nucleic acid probes. We describe two approaches for an expeditious preparation of chromosome-specific DNAs and the subsequent probe labeling with reporter molecules of choice. The described techniques allow the preparation of highly specific DNA repeat probes suitable for enumeration of chromosomes in interphase cell nuclei or tissue sections. In addition, there is no need for chromosome enrichment by flow cytometry and sorting or molecular cloning. Our PCR-based method uses either bacterial artificial chromosomes or human genomic DNA as templates with {alpha}-satellite-specific primers. Here we demonstrate the production of fluorochrome-labeled DNA repeat probes specific for human chromosomes 17 and 18 in just a few days without the need for highly specialized equipment and without the limitation to only a few fluorochrome labels.

  20. Relationship between income and repeat criminal victimization in Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo Justus

    2015-09-01

    Full Text Available This study analyzes the effect of income on repeat criminal victimization in Brazil using data from the 2009 National Household Sample Survey and its special supplement on victimization and access to justice. Two count-data models were estimated for four types of crime: theft, robbery, attempted theft/robbery, and physical assault. A positive nonlinear effect of income on repeat victimization for the three types of property crimes and a negative nonlinear effect of income on physical assault were observed.

  1. Repeat polymorphisms in ESR2 and AR and colorectal cancer risk and prognosis: results from a German population-based case-control study.

    Science.gov (United States)

    Rudolph, Anja; Shi, Hong; Försti, Asta; Hoffmeister, Michael; Sainz, Juan; Jansen, Lina; Hemminki, Kari; Brenner, Hermann; Chang-Claude, Jenny

    2014-11-07

    Evidence has accumulated which suggests that sex steroids influence colorectal cancer development and progression. We therefore assessed the association of repeat polymorphisms in the estrogen receptor β gene (ESR2) and the androgen receptor gene (AR) with colorectal cancer risk and prognosis. The ESR2 CA and AR CAG repeat polymorphisms were genotyped in 1798 cases (746 female, 1052 male) and 1810 controls (732 female, 1078 male), matched for sex, age and county of residence. Colorectal cancer risk associations overall and specific for gender were evaluated using multivariate logistic regression models adjusted for sex, county of residence and age. Associations with overall and disease-specific survival were evaluated using Cox proportional hazard models adjusted for established prognostic factors (diagnosis of other cancer after colorectal cancer diagnosis, detection by screening, treatment with adjuvant chemotherapy, tumour extent, nodal status, distant metastasis, body mass index, age at diagnosis and year of diagnosis) and stratified for grade of differentiation. Heterogeneity in gender specific associations was assessed by comparing models with and without a multiplicative interaction term by means of a likelihood ratio test. The average number of ESR2 CA repeats was associated with a small 5% increase in colorectal cancer risk (OR = 1.05, 95% CI 1.01-1.10) without significant heterogeneity according to gender or tumoural ESR2 expression. We found no indication for an association between the AR CAG repeat polymorphisms and risk of colorectal cancer. The ESR2 CA and AR CAG repeat polymorphisms were not associated with overall survival or disease specific survival after colorectal cancer diagnosis. Higher numbers of ESR2 CA repeats are potentially associated with a small increase in colorectal cancer risk. Our study does not support an association between colorectal cancer prognosis and the investigated repeat polymorphisms.

  2. Smooth muscle fatigue due to repeated urinary bladder neurostimulation: an in vivo study.

    Science.gov (United States)

    Bross, S; Schumacher, S; Scheepe, J R; Seif, C; Jünemann, K P; Alken, P

    1999-01-01

    The presented study investigates the influence of different pause lengths between two consecutive stimulations of the S3 roots on intravesical pressure during bladder neurostimulation. In eight male foxhounds (aged 7-18 months), laminectomy and placement of a modified Brindley electrode were performed. In four series with different pause lengths between two consecutive stimulations (1, 3, 5, and 15 min), the maximum intravesical pressure was measured during stimulation. The changes in intravesical pressure were registered in these four series, each series with six stimulations. A 15-min interval elapsed before the commencement of each series. In the series with a pause length of 15 min, the consecutive stimulations did not result in significant changes in maximum intravesical pressure. In the 5-min series, a significant decrease in intravesical pressure was not observed after the third stimulation. In the 3-min series, a significant decrease was seen at almost every stimulation (average decrease of 3.8% per stimulation) and in the 1-min series, a significant decrease was also observed at almost every stimulation (average decrease of 5.9% per stimulation). The results of repeated bladder neurostimulation demonstrate that the maximum intravesical pressure is dependent on the pause length between two consecutive stimulations. The detrusor muscle showed reversible and short-lived signs of fatigue. This implies the importance of a minimum 5-min interval between two subsequent stimulations. A pause length <5 min leads to a falsification of the results and thus to lower validity of the investigation.

  3. Medial temporal lobe-dependent repetition suppression and enhancement due to implicit versus explicit processing of individual repeated search displays

    Directory of Open Access Journals (Sweden)

    Thomas eGeyer

    2012-10-01

    Full Text Available Using visual search, functional magnetic resonance imaging (fMRI and patient studies have demonstrated that medial temporal lobe (MTL structures differentiate repeated from novel displays – even when observers are unaware of display repetitions. This suggests a role for MTL in both explicit and, importantly, implicit learning of repeated sensory information (Greene et al., 2007. However, recent behavioral studies suggest, by examining visual search and recognition performance concurrently, that observers have explicit knowledge of at least some of the repeated displays (Geyer et al., 2010. The aim of the present fMRI study was thus to contribute new evidence regarding the contribution of MTL structures to explicit versus implicit learning in visual search. It was found that MTL activation was increased for explicit and, respectively, decreased for implicit relative to baseline displays. These activation differences were most pronounced in left anterior parahippocampal cortex, especially when observers were highly trained on the repeated displays. The data are taken to suggest that explicit and implicit memory processes are linked within MTL structures, but expressed via functionally separable mechanisms (repetition enhancement vs. -suppression. They further show that repetition effects in visual search would have to be investigated at the display level.

  4. Repeated anaesthesia with isoflurane and medetomidine-midazolam-fentanyl in guinea pigs and its influence on physiological parameters.

    Directory of Open Access Journals (Sweden)

    Sabrina Schmitz

    Full Text Available Repeated anaesthesia may be required in experimental protocols and in daily veterinary practice, but anaesthesia is known to alter physiological parameters in GPs (Cavia porcellus, GPs. This study investigated the effects of repeated anaesthesia with either medetomidine-midazolam-fentanyl (MMF or isoflurane (Iso on physiological parameters in the GP. Twelve GPs were repeatedly administered with MMF or Iso in two anaesthesia sets. One set consisted of six 40-min anaesthesias, performed over 3 weeks (2 per week; the anaesthetic used first was randomized. Prior to Iso anaesthesia, atropine was injected. MMF anaesthesia was antagonized with AFN (atipamezole-flumazenil-naloxone. Abdominally implanted radio-telemetry devices recorded the mean arterial blood pressure (MAP, heart rate (HR and core body temperature continuously. Additionally, respiratory rate, blood glucose and body weight were assessed. An operable state could be achieved and maintained for 40 min in all GPs. During the surgical tolerance with MMF, the GPs showed a large MAP range between the individuals. In the MMF wake- up phase, the time was shortened until the righting reflex (RR returned and that occurred at lower MAP and HR values. Repeated Iso anaesthesia led to an increasing HR during induction (anaesthesias 2-6, non-surgical tolerance (anaesthesias 3-6 and surgical tolerance (anaesthesias 4, 6. Both anaesthetics may be used repeatedly, as repeating the anaesthesias resulted in only slightly different physiological parameters, compared to those seen with single anaesthesias. The regular atropine premedication induced HR increases and repeated MMF anaesthesia resulted in a metabolism increase which led to the faster return of RR. Nevertheless, Iso's anaesthesia effects of strong respiratory depression and severe hypotension remained. Based on this increased anaesthesia risk with Iso, MMF anaesthesia is preferable for repeated use in GPs.

  5. Repeated imitation makes human vocalizations more word-like.

    Science.gov (United States)

    Edmiston, Pierce; Perlman, Marcus; Lupyan, Gary

    2018-03-14

    People have long pondered the evolution of language and the origin of words. Here, we investigate how conventional spoken words might emerge from imitations of environmental sounds. Does the repeated imitation of an environmental sound gradually give rise to more word-like forms? In what ways do these forms resemble the original sounds that motivated them (i.e. exhibit iconicity)? Participants played a version of the children's game 'Telephone'. The first generation of participants imitated recognizable environmental sounds (e.g. glass breaking, water splashing). Subsequent generations imitated the previous generation of imitations for a maximum of eight generations. The results showed that the imitations became more stable and word-like, and later imitations were easier to learn as category labels. At the same time, even after eight generations, both spoken imitations and their written transcriptions could be matched above chance to the category of environmental sound that motivated them. These results show how repeated imitation can create progressively more word-like forms while continuing to retain a resemblance to the original sound that motivated them, and speak to the possible role of human vocal imitation in explaining the origins of at least some spoken words. © 2018 The Author(s).

  6. Novel expressed sequence tag- simple sequence repeats (EST ...

    African Journals Online (AJOL)

    Using different bioinformatic criteria, the SUCEST database was used to mine for simple sequence repeat (SSR) markers. Among 42,189 clusters, 1,425 expressed sequence tag- simple sequence repeats (EST-SSRs) were identified in silico. Trinucleotide repeats were the most abundant SSRs detected. Of 212 primer pairs ...

  7. Absence of bacterial resistance following repeat exposure to photodynamic therapy

    Science.gov (United States)

    Pedigo, Lisa A.; Gibbs, Aaron J.; Scott, Robert J.; Street, Cale N.

    2009-06-01

    The prevalence of antibiotic resistant bacteria necessitates exploration of alternative approaches to treat hospital and community acquired infections. The aim of this study was to determine whether bacterial pathogens develop resistance to antimicrobial photodynamic therapy (aPDT) during repeated sub-lethal challenge. Antibiotic sensitive and resistant strains of S. aureus and antibiotic sensitive E. coli were subjected to repeat PDT treatments using a methylene blue photosensitizer formulation and 670 nm illumination from a non-thermal diode laser. Parameters were adjusted such that kills were antibiotic resistance strains. Furthermore, repeated sub-lethal exposure does not induce resistance to subsequent PDT treatments. The absence of resistance formation represents a significant advantage of PDT over traditional antibiotics.

  8. Repeated experimental fires and window of disturbance in relation to runoff in a Mediterranean shrubland

    Directory of Open Access Journals (Sweden)

    E. Gimeno-García

    2013-05-01

    Full Text Available This study is focused on exploring the effect of repeated experimental fires on post-fire runoff generation through a sixteen years monitoring runoff yield from erosion plots (eight years after the first fire and other eight years after the second one in a Mediterranean shrubland area (La Concordia Experimental Station, considering the fire severity and the post-fire erosive rainfall events. The conceptual framework of the window of disturbance is used to analyze how long the runoff yield in burned plots shows clear differences respect to the unburned ones, as well as, the recovery-rate model for multiple fire events. Results show that the effect of repeated fires on runoff yield is related to a combination of fire severity, climatic conditions (mainly rainfall intensity, I30, soil hydrological properties (infiltration capacity, steady state infiltration and soil water retention capacity, and rate of vegetation recovery. Eight years after the first fire, even though soil hydrological properties are recovered as well as vegetation cover did, rainfall events with I30 ≥20 mm h-1 still promoted differences between burned and control plots. The second post-fire disturbance period was associated with the low vegetation recovery, and also with rainfall events with I30 ≥20 mm h-1 even seven years after the repeated fires.

  9. Comparing Young and Elderly Serial Reaction Time Task Performance on Repeated and Random Conditions

    Directory of Open Access Journals (Sweden)

    Fatemeh Ehsani

    2012-07-01

    Full Text Available Objectives: Acquisition motor skill training in elderly is at great importance. The main purpose of this study was to compare young and elderly performance in serial reaction time task on different repeated and random conditions. Methods & Materials: A serial reaction time task by using software was applied for studying motor learning in 30 young and 30 elderly. Each group divided randomly implicitly and explicitly into subgroups. A task 4 squares with different colors appeared on the monitor and subjects were asked to press its defined key immediately after observing it. Subjects practiced 8 motor blocks (4 repeated blocks, then 2 random blocks and 2 repeated blocks. Block time that was dependent variable measured and Independent-samples t- test with repeated ANOVA measures were used in this test. Results: young groups performed both repeated and random sequences significantly faster than elderly (P0.05. Explicit older subgroup performed 7,8 blocks slower than 6 block with a significant difference (P<0.05. Conclusion: Young adults discriminate high level performance than elderly in both repeated and random practice. Elderly performed random practice better than repeated practice.

  10. Validity and repeatability of inertial measurement units for measuring gait parameters.

    Science.gov (United States)

    Washabaugh, Edward P; Kalyanaraman, Tarun; Adamczyk, Peter G; Claflin, Edward S; Krishnan, Chandramouli

    2017-06-01

    Inertial measurement units (IMUs) are small wearable sensors that have tremendous potential to be applied to clinical gait analysis. They allow objective evaluation of gait and movement disorders outside the clinic and research laboratory, and permit evaluation on large numbers of steps. However, repeatability and validity data of these systems are sparse for gait metrics. The purpose of this study was to determine the validity and between-day repeatability of spatiotemporal metrics (gait speed, stance percent, swing percent, gait cycle time, stride length, cadence, and step duration) as measured with the APDM Opal IMUs and Mobility Lab system. We collected data on 39 healthy subjects. Subjects were tested over two days while walking on a standard treadmill, split-belt treadmill, or overground, with IMUs placed in two locations: both feet and both ankles. The spatiotemporal measurements taken with the IMU system were validated against data from an instrumented treadmill, or using standard clinical procedures. Repeatability and minimally detectable change (MDC) of the system was calculated between days. IMUs displayed high to moderate validity when measuring most of the gait metrics tested. Additionally, these measurements appear to be repeatable when used on the treadmill and overground. The foot configuration of the IMUs appeared to better measure gait parameters; however, both the foot and ankle configurations demonstrated good repeatability. In conclusion, the IMU system in this study appears to be both accurate and repeatable for measuring spatiotemporal gait parameters in healthy young adults. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. The effect of repeated applanation on subsequent IOP measurements.

    Science.gov (United States)

    AlMubrad, Turki M; Ogbuehi, Kelechi C

    2008-11-01

    In studies aimed at assessing the accuracy and repeatability of non-contact tonometers, the order in which these tonometers and the Goldmann tonometer are used is usually randomised despite studies in the literature that demonstrate an ocular massage effect that occurs post-applanation but not after non-contact tonometry. The purpose of this study was to investigate the effect of repeated corneal applanation on subsequent assessments of IOP. Data were obtained from 65 left eyes of 65 young, oculovisual normals. Three sets of IOP measurements were obtained, one set with the Goldmann applanation tonometer and two with the Topcon CT80 non-contact tonometer (one set each before and after applanation with the Goldmann tonometer), in each one of two separate measurement sessions, one week apart. The average (and SD) IOP measured with the Goldmann tonometer in the first session (14.8+/-2.9 mmHg) did not vary significantly from the IOP measured with the non-contact tonometer (pre-applanation) in both sessions or with the average Goldmann IOP in the second session. The bias (mean difference +/- SD) between methods was 0.3+/-1.4 mmHg and 0.4+/-1.4 mmHg, respectively, for the first and second sessions, with the CT80 (pre-applanation) recording the higher IOP in both sessions. The within-session repeatability coefficients were +/-2.3 mmHg, +/-2.6 mmHg, +/-2.1 mmHg and +/-2.0 mmHg for the CT80 (pre-applanation) in the first and second sessions, and the Goldmann tonometer in the first and second sessions, respectively. Test-retest repeatability coefficients were +/-2.8 mmHg and +/-2.5 mmHg for the CT80 (pre-applanation) and the Goldmann tonometer respectively. Post-applanation with the Goldmann tonometer, there was a statistically significant (pcontact tonometer in both sessions. These results suggest that repeated corneal applanation leads to a statistically significant reduction in IOP on subsequent measurements.

  12. Association of aromatase (TTTA)n repeat polymorphisms with central precocious puberty in girls.

    Science.gov (United States)

    Lee, Hae Sang; Kim, Kyung Hee; Hwang, Jin Soon

    2014-09-01

    Precocious puberty is characterized by early activation of the pituitary-gonadal axis. Oestrogen is the final key factor to start the onset of puberty. The cytochrome P450 19A1 (CYP19A1) gene encodes an aromatase that is responsible for the conversion of androgens to oestrogen, which is a key step in oestrogen biosynthesis. The aim of this study was to identify CYP19A1 gene mutations or polymorphisms in girls with central precocious puberty (CPP). We evaluated the frequency of allelic variants of the CYP19A1 exons and the tetranucleotide tandem repeat (TTTA)n in intron 4 in 203 idiopathic central precocious puberty (CPP) girls and 101 normal healthy women. The genotype analysis of the CYP19A1 (TTTA)n polymorphism revealed six different alleles ranging from seven to 13 repeats. Among the six different repeat alleles detected in this study, the (TTTA)₁₃ repeat allele was only detected in the patient group and carriers of the (TTTA)₁₃ allele were significantly associated with an increased risk of CPP (OR = 1·509, 95% CI = 1·425-1·598, P = 0·033). Carriers of the (TTTA)₁₃ repeat allele were significantly younger at pubertal onset and had higher levels of oestrogen than noncarriers of the (TTTA)₁₃ repeat allele. Although nine polymorphisms were detected in exons of the CYP19A1 gene, no clinical significance was observed. In this study, carriers of a higher repeat (TTTA)₁₃ polymorphism in intron 4 of the CYP19A1 gene had higher levels of oestrogen. Those carrying the (TTTA)₁₃ repeat allele may have a higher risk of developing CPP. © 2014 John Wiley & Sons Ltd.

  13. Safety of Repeated Yttrium-90 Radioembolization

    International Nuclear Information System (INIS)

    Lam, Marnix G. E. H.; Louie, John D.; Iagaru, Andrei H.; Goris, Michael L.; Sze, Daniel Y.

    2013-01-01

    Purpose: Repeated radioembolization (RE) treatments carry theoretically higher risk of radiation-induced hepatic injury because of the liver’s cumulative memory of previous exposure. We performed a retrospective safety analysis on patients who underwent repeated RE. Methods: From 2004 to 2011, a total of 247 patients were treated by RE. Eight patients (5 men, 3 women, age range 51–71 years) underwent repeated treatment of a targeted territory, all with resin microspheres (SIR-Spheres; Sirtex, Lane Cove, Australia). Adverse events were graded during a standardized follow-up. In addition, the correlation between the occurrence of RE-induced liver disease (REILD) and multiple variables was investigated in univariate and multivariate analyses in all 247 patients who received RE. Results: Two patients died shortly after the second treatment (at 84 and 107 days) with signs and symptoms of REILD. Both patients underwent whole liver treatment twice (cumulative doses 3.08 and 2.66 GBq). The other 6 patients demonstrated only minor toxicities after receiving cumulative doses ranging from 2.41 to 3.88 GBq. All patients experienced objective tumor responses. In the whole population, multifactorial analysis identified three risk factors associated with REILD: repeated RE (p = 0.036), baseline serum total bilirubin (p = 0.048), and baseline serum aspartate aminotransferase (p = 0.043). Repeated RE proved to be the only independent risk factor for REILD in multivariate analysis (odds ratio 9.6; p = 0.002). Additionally, the administered activity per target volume (in GBq/L) was found to be an independent risk factor for REILD, but only in whole liver treatments (p = 0.033). Conclusion: The risk of REILD appears to be elevated for repeated RE. Objective tumor responses were observed, but establishment of safety limits will require improvement in dosimetric measurement and prediction

  14. Safety of Repeated Yttrium-90 Radioembolization

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Marnix G. E. H.; Louie, John D. [Stanford University School of Medicine, Division of Interventional Radiology (United States); Iagaru, Andrei H.; Goris, Michael L. [Stanford University School of Medicine, Division of Nuclear Medicine (United States); Sze, Daniel Y., E-mail: dansze@stanford.edu [Stanford University School of Medicine, Division of Interventional Radiology (United States)

    2013-10-15

    Purpose: Repeated radioembolization (RE) treatments carry theoretically higher risk of radiation-induced hepatic injury because of the liver's cumulative memory of previous exposure. We performed a retrospective safety analysis on patients who underwent repeated RE. Methods: From 2004 to 2011, a total of 247 patients were treated by RE. Eight patients (5 men, 3 women, age range 51-71 years) underwent repeated treatment of a targeted territory, all with resin microspheres (SIR-Spheres; Sirtex, Lane Cove, Australia). Adverse events were graded during a standardized follow-up. In addition, the correlation between the occurrence of RE-induced liver disease (REILD) and multiple variables was investigated in univariate and multivariate analyses in all 247 patients who received RE. Results: Two patients died shortly after the second treatment (at 84 and 107 days) with signs and symptoms of REILD. Both patients underwent whole liver treatment twice (cumulative doses 3.08 and 2.66 GBq). The other 6 patients demonstrated only minor toxicities after receiving cumulative doses ranging from 2.41 to 3.88 GBq. All patients experienced objective tumor responses. In the whole population, multifactorial analysis identified three risk factors associated with REILD: repeated RE (p = 0.036), baseline serum total bilirubin (p = 0.048), and baseline serum aspartate aminotransferase (p = 0.043). Repeated RE proved to be the only independent risk factor for REILD in multivariate analysis (odds ratio 9.6; p = 0.002). Additionally, the administered activity per target volume (in GBq/L) was found to be an independent risk factor for REILD, but only in whole liver treatments (p = 0.033). Conclusion: The risk of REILD appears to be elevated for repeated RE. Objective tumor responses were observed, but establishment of safety limits will require improvement in dosimetric measurement and prediction.

  15. Hearing loss associated with repeated MRI acquisition procedure-related acoustic noise exposure: an occupational cohort study.

    Science.gov (United States)

    Bongers, Suzan; Slottje, Pauline; Kromhout, Hans

    2017-11-01

    To study the effects of repeated exposure to MRI-related acoustic noise during image acquisition procedures (scans) on hearing. A retrospective occupational cohort study was performed among workers of an MRI manufacturing facility (n=474). Longitudinal audiometry data from the facility's medical surveillance scheme collected from 1973 to 2010 were analysed by studying the association of cumulative exposure to MRI-related acoustic noise from voluntary (multiple) MRI scans and the hearing threshold of the volunteer. Repeated acoustic noise exposure during volunteer MRI scans was found to be associated with a small exposure-dependent increased rate change of hearing threshold level (dB/year), but the association was only found related to the number of voluntary MRI scans and not to modelled cumulative noise exposure (dB*hour) based on MRI-system type. The increased rate change of hearing threshold level was found to be statistically significant for the frequencies 500, 1000, 2000, 3000 and 4000 Hz in the right ear. From our longitudinal cohort study, it appeared that exposure to noise from voluntarily MRI scans may have resulted in a slight amount of hearing loss. Mandatory use of hearing protection might have prevented more severe hearing loss. Lack of consistency in findings between the left and right ears and between the two exposure measures prohibits definitive conclusions. Further research that addresses the study's methodological limitations is warranted to corroborate our findings. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  16. Repeated verum but not placebo acupuncture normalizes connectivity in brain regions dysregulated in chronic pain

    Directory of Open Access Journals (Sweden)

    Natalia Egorova

    2015-01-01

    Full Text Available Acupuncture, an ancient East Asian therapy, is aimed at rectifying the imbalance within the body caused by disease. Studies evaluating the efficacy of acupuncture with neuroimaging tend to concentrate on brain regions within the pain matrix, associated with acute pain. We, however, focused on the effect of repeated acupuncture treatment specifically on brain regions known to support functions dysregulated in chronic pain disorders. Transition to chronic pain is associated with increased attention to pain, emotional rumination, nociceptive memory and avoidance learning, resulting in brain connectivity changes, specifically affecting the periaqueductal gray (PAG, medial frontal cortex (MFC and bilateral hippocampus (Hpc. We demonstrate that the PAG–MFC and PAG–Hpc connectivity in patients with chronic pain due to knee osteoarthritis indeed correlates with clinical severity scores and further show that verum acupuncture-induced improvement in pain scores (compared to sham is related to the modulation of PAG–MFC and PAG–Hpc connectivity in the predicted direction. This study shows that repeated verum acupuncture might act by restoring the balance in the connectivity of the key pain brain regions, altering pain-related attention and memory.

  17. Erroneous Memories Arising from Repeated Attempts to Remember

    Science.gov (United States)

    Henkel, Linda A.

    2004-01-01

    The impact of repeated and prolonged attempts at remembering on false memory rates was assessed in three experiments. Participants saw and imagined pictures and then made repeated recall attempts before taking a source memory test. Although the number of items recalled increased with repeated tests, the net gains were associated with more source…

  18. Repeated dose titration versus age-based method in electroconvulsive therapy: a pilot study

    NARCIS (Netherlands)

    Aten, J.J.; Oudega, M.L.; van Exel, E.; Stek, M.L.; van Waarde, J.A.

    2015-01-01

    In electroconvulsive therapy (ECT), a dose titration method (DTM) was suggested to be more individualized and therefore more accurate than formula-based dosing methods. A repeated DTM (every sixth session and dose adjustment accordingly) was compared to an age-based method (ABM) regarding treatment

  19. When being narrow minded is a good thing: locally biased people show stronger contextual cueing.

    Science.gov (United States)

    Bellaera, Lauren; von Mühlenen, Adrian; Watson, Derrick G

    2014-01-01

    Repeated contexts allow us to find relevant information more easily. Learning such contexts has been proposed to depend upon either global processing of the repeated contexts, or alternatively processing of the local region surrounding the target information. In this study, we measured the extent to which observers were by default biased to process towards a more global or local level. The findings showed that the ability to use context to help guide their search was strongly related to an observer's local/global processing bias. Locally biased people could use context to help improve their search better than globally biased people. The results suggest that the extent to which context can be used depends crucially on the observer's attentional bias and thus also to factors and influences that can change this bias.

  20. On model selections for repeated measurement data in clinical studies.

    Science.gov (United States)

    Zou, Baiming; Jin, Bo; Koch, Gary G; Zhou, Haibo; Borst, Stephen E; Menon, Sandeep; Shuster, Jonathan J

    2015-05-10

    Repeated measurement designs have been widely used in various randomized controlled trials for evaluating long-term intervention efficacies. For some clinical trials, the primary research question is how to compare two treatments at a fixed time, using a t-test. Although simple, robust, and convenient, this type of analysis fails to utilize a large amount of collected information. Alternatively, the mixed-effects model is commonly used for repeated measurement data. It models all available data jointly and allows explicit assessment of the overall treatment effects across the entire time spectrum. In this paper, we propose an analytic strategy for longitudinal clinical trial data where the mixed-effects model is coupled with a model selection scheme. The proposed test statistics not only make full use of all available data but also utilize the information from the optimal model deemed for the data. The performance of the proposed method under various setups, including different data missing mechanisms, is evaluated via extensive Monte Carlo simulations. Our numerical results demonstrate that the proposed analytic procedure is more powerful than the t-test when the primary interest is to test for the treatment effect at the last time point. Simulations also reveal that the proposed method outperforms the usual mixed-effects model for testing the overall treatment effects across time. In addition, the proposed framework is more robust and flexible in dealing with missing data compared with several competing methods. The utility of the proposed method is demonstrated by analyzing a clinical trial on the cognitive effect of testosterone in geriatric men with low baseline testosterone levels. Copyright © 2015 John Wiley & Sons, Ltd.

  1. Repeated batch and continuous degradation of chlorpyrifos by Pseudomonas putida.

    Science.gov (United States)

    Pradeep, Vijayalakshmi; Subbaiah, Usha Malavalli

    2015-01-01

    The present study was undertaken with the objective of studying repeated batch and continuous degradation of chlorpyrifos (O,O-diethyl O-3,5,6-trichloropyridin-2-yl phosphorothioate) using Ca-alginate immobilized cells of Pseudomonas putida isolated from an agricultural soil, and to study the genes and enzymes involved in degradation. The study was carried out to reduce the toxicity of chlorpyrifos by degrading it to less toxic metabolites. Long-term stability of pesticide degradation was studied during repeated batch degradation of chlorpyrifos, which was carried out over a period of 50 days. Immobilized cells were able to show 65% degradation of chlorpyrifos at the end of the 50th cycle with a cell leakage of 112 × 10(3) cfu mL(-1). During continuous treatment, 100% degradation was observed at 100 mL h(-1) flow rate with 2% chlorpyrifos, and with 10% concentration of chlorpyrifos 98% and 80% degradation was recorded at 20 mL h(-1) and 100 mL h(-1) flow rate respectively. The products of degradation detected by liquid chromatography-mass spectrometry analysis were 3,5,6-trichloro-2-pyridinol and chlorpyrifos oxon. Plasmid curing experiments with ethidium bromide indicated that genes responsible for the degradation of chlorpyrifos are present on the chromosome and not on the plasmid. The results of Polymerase chain reaction indicate that a ~890-bp product expected for mpd gene was present in Ps. putida. Enzymatic degradation studies indicated that the enzymes involved in the degradation of chlorpyrifos are membrane-bound. The study indicates that immobilized cells of Ps. putida have the potential to be used in bioremediation of water contaminated with chlorpyrifos.

  2. Lesser Neural Pattern Similarity across Repeated Tests Is Associated with Better Long-Term Memory Retention.

    Science.gov (United States)

    Karlsson Wirebring, Linnea; Wiklund-Hörnqvist, Carola; Eriksson, Johan; Andersson, Micael; Jonsson, Bert; Nyberg, Lars

    2015-07-01

    Encoding and retrieval processes enhance long-term memory performance. The efficiency of encoding processes has recently been linked to representational consistency: the reactivation of a representation that gets more specific each time an item is further studied. Here we examined the complementary hypothesis of whether the efficiency of retrieval processes also is linked to representational consistency. Alternatively, recurrent retrieval might foster representational variability--the altering or adding of underlying memory representations. Human participants studied 60 Swahili-Swedish word pairs before being scanned with fMRI the same day and 1 week later. On Day 1, participants were tested three times on each word pair, and on Day 7 each pair was tested once. A BOLD signal change in right superior parietal cortex was associated with subsequent memory on Day 1 and with successful long-term retention on Day 7. A representational similarity analysis in this parietal region revealed that beneficial recurrent retrieval was associated with representational variability, such that the pattern similarity on Day 1 was lower for retrieved words subsequently remembered compared with those subsequently forgotten. This was mirrored by a monotonically decreased BOLD signal change in dorsolateral prefrontal cortex on Day 1 as a function of repeated successful retrieval for words subsequently remembered, but not for words subsequently forgotten. This reduction in prefrontal response could reflect reduced demands on cognitive control. Collectively, the results offer novel insights into why memory retention benefits from repeated retrieval, and they suggest fundamental differences between repeated study and repeated testing. Repeated testing is known to produce superior long-term retention of the to-be-learned material compared with repeated encoding and other learning techniques, much because it fosters repeated memory retrieval. This study demonstrates that repeated memory

  3. Identification, variation and transcription of pneumococcal repeat sequences

    Science.gov (United States)

    2011-01-01

    Background Small interspersed repeats are commonly found in many bacterial chromosomes. Two families of repeats (BOX and RUP) have previously been identified in the genome of Streptococcus pneumoniae, a nasopharyngeal commensal and respiratory pathogen of humans. However, little is known about the role they play in pneumococcal genetics. Results Analysis of the genome of S. pneumoniae ATCC 700669 revealed the presence of a third repeat family, which we have named SPRITE. All three repeats are present at a reduced density in the genome of the closely related species S. mitis. However, they are almost entirely absent from all other streptococci, although a set of elements related to the pneumococcal BOX repeat was identified in the zoonotic pathogen S. suis. In conjunction with information regarding their distribution within the pneumococcal chromosome, this suggests that it is unlikely that these repeats are specialised sequences performing a particular role for the host, but rather that they constitute parasitic elements. However, comparing insertion sites between pneumococcal sequences indicates that they appear to transpose at a much lower rate than IS elements. Some large BOX elements in S. pneumoniae were found to encode open reading frames on both strands of the genome, whilst another was found to form a composite RNA structure with two T box riboswitches. In multiple cases, such BOX elements were demonstrated as being expressed using directional RNA-seq and RT-PCR. Conclusions BOX, RUP and SPRITE repeats appear to have proliferated extensively throughout the pneumococcal chromosome during the species' past, but novel insertions are currently occurring at a relatively slow rate. Through their extensive secondary structures, they seem likely to affect the expression of genes with which they are co-transcribed. Software for annotation of these repeats is freely available from ftp://ftp.sanger.ac.uk/pub/pathogens/strep_repeats/. PMID:21333003

  4. Nonparametric additive regression for repeatedly measured data

    KAUST Repository

    Carroll, R. J.; Maity, A.; Mammen, E.; Yu, K.

    2009-01-01

    We develop an easily computed smooth backfitting algorithm for additive model fitting in repeated measures problems. Our methodology easily copes with various settings, such as when some covariates are the same over repeated response measurements

  5. Repeated Recall and PKM? Maintain Fear Memories in Juvenile Rats

    Science.gov (United States)

    Oliver, Chicora F.; Kabitzke, Patricia; Serrano, Peter; Egan, Laura J.; Barr, Gordon A.; Shair, Harry N.; Wiedenmayer, Christoph

    2016-01-01

    We examined the neural substrates of fear memory formation and maintenance when repeated recall was used to prevent forgetting in young animals. In contrast to adult rats, juveniles failed to show contextual fear responses at 4 d post-fear conditioning. Reconsolidation sessions 3 and 6 d after conditioning restored contextual fear responses in…

  6. One-time versus repeated abutment connection for platform-switched implant: A systematic review and meta-analysis.

    Science.gov (United States)

    Wang, Qing-Qing; Dai, Ruoxi; Cao, Chris Ying; Fang, Hui; Han, Min; Li, Quan-Li

    2017-01-01

    This review aims to compare peri-implant tissue changes in terms of clinical and radiographic aspects of implant restoration protocol using one-time abutment to repeated abutment connection in platform switched implant. A structured search strategy was applied to three electronic databases, namely, Pubmed, Embase and Web of Science. Eight eligible studies, including seven randomised controlled studies and one controlled clinical study, were identified in accordance with inclusion/exclusion criteria. Outcome measures included peri-implant bone changes (mm), peri-implant soft tissue changes (mm), probing depth (mm) and postsurgical complications. Six studies were pooled for meta-analysis on bone tissue, three for soft tissue, two for probing depth and four for postsurgical complications. A total of 197 implants were placed in one-time abutment group, whereas 214 implants were included in repeated abutment group. The implant systems included Global implants, Ankylos, JDEvolution (JdentalCare), Straumann Bone level and Conelog-Screwline. One-time abutment group showed significantly better outcomes than repeated abutment group, as measured in the standardised differences in mean values (fixed- and random-effect model): vertical bone change (0.41, 3.23) in 6 months, (1.51, 14.81) in 12 months and (2.47, 2.47) in 3 years and soft tissue change (0.21, 0.23). No significant difference was observed in terms of probing depth and complications. Our meta-analysis revealed that implant restoration protocol using one-time abutment is superior to repeated abutment for platform switched implant because of less bone resorption and soft tissue shifts in former. However, future randomised clinical trials should be conducted to further confirm these findings because of the small samples and the limited quality of the original research.

  7. Dependence of the polar Kerr angle and coercivity on repeat distance in sequentially prepared Tb/FeCo films

    International Nuclear Information System (INIS)

    Shin, S.

    1991-01-01

    Multilayer thin films of Tb and FeCo were prepared by sequential thermal evaporation of Tb and Fe 90 Co 10 alloy on glass substrates at ambient temperature in a vacuum of about 1 x 10 -6 Torr. The repeat distance of the films was varied from 3.5 to 175 A while maintaining the composition constant for all samples. Low-angle x-ray diffraction and Auger electron spectroscopy showed that a multilayer structure was achieved for films fabricated with a repeat distance Λ≥31.5 A. The polar Kerr rotation angle and coercivity of the samples were obtained by measuring the polar Kerr hysteresis loop using a 632.8-nm HeNe laser. It was observed that for the samples having a multilayer structure, the remnant Kerr angle and coercivity monotonically decreased with increasing repeat distance, and eventually disappeared for Λ≥70 A. For the samples showing a nonmultilayer structure, the remnant Kerr angle was independent of repeat distance. However, the coercivity increased with repeat distance until a broad maximum was obtained around Λ congruent 14--21 A

  8. Repeated CT studies of a patient with herpes simplex encephalitis during his entire clinical course

    International Nuclear Information System (INIS)

    Shiraishi, Masahiro; Fukui, Keiji; Takeda, Sadanori; Sadamoto, Kazuhiko; Kimura, Hideki; Sakaki, Saburo.

    1985-01-01

    We encountered a patient with herpes simplex encephalitis whose cerebral lesions were studied by repeated CT scannings during his entire clinical course. The purpose of this paper is to report the earliest lesions of the brain as revealed by CT scans. A 63-year-old man was admitted to our clinic complaining of headache, nausea, fever, and disorientation. On admission, a physical examination showed a high fever, while a neurological examination revealed a stiff neck, a positive Kernig's sign, and disorientation. Laboratory examinations revealed a pleocytosis of the cerebrospinal fluid. Electroencephalograms showed the so-called ''periodic sharp-and-slow-waves complex''. The complement fixation titer for herpes simplex virus was x32 in the serum and x128 in the cerebrospinal fluid, suggesting the diagnosis of herpes simplex encephalitis. We treated him with adenine arabinoside and gamma-globulin, but the patient did not recover; rather, he died of pneumonia and gastrointestinal bleeding three months later. Plain CT scans taken on the 12th day after the onset revealed a low-density area with signs of a slight mass in the region from the right island of Reil to the right uncus. Contrast-enhanced CT scans revealed an irregular enhancement in the low-density area. CT scans taken on the 19th day after the onset showed an extensive low-density area with a streak-like enhancement in the right temporal lobe, which is in aggreement with the findings reported by others as characteristic CT findings for herpes simplex encephalitis. In order to make an early diagnosis of a patient, we should pay attention to a low-density area with an irregular contrast enhancement in the region from the island of Reil to the uncus on a CT scan. (author)

  9. "Focused introspection" during naturally increased diuresis: description and repeatability of a method to study bladder sensation non-invasively.

    Science.gov (United States)

    De Wachter, Stefan G G; Heeringa, Rhea; Van Koeveringe, Gommert A; Winkens, Bjorn; Van Kerrebroeck, Philip E V; Gillespie, James I

    2014-06-01

    To present and describe a non-invasive method to study the origin and development of bladder filling sensation and to evaluate the repeatability of the method. Eighteen volunteers participated in the study and were given a water loading protocol consisting of 1,000 ml water intake 1 hr before the session and 200 ml every 10 min during the session. Protocol 1: To evaluate diuresis rate, seven participants were asked to void every 15 min and the voided volume was measured. Protocol 2: Eleven volunteers graded bladder sensation on regular time points, on an empty graph with time on the X-axis and intensity of sensation on the Y-axis. The protocol ended at absolute need to void (maximal intensity) and voided volumes were measured. This protocol was conducted three times with a 10 days interval. Protocol 1: The diuresis rate was not different during the sessions and showed no variation over the studied time period (P = 0.2). Protocol 2: For an individual, the diuresis rate was not different between the sessions. The curves in all patients showed a continuously increasing bladder intensity. In seven participants the curve was convex, in the other four, the curve was sigmoidal. For each individual the pattern was constant during the three sessions. A strict water loading protocol induces a constant diuresis. This allows individuals to draw an introspection bladder sensation curve with a specific shape, which can be used as a method to study the development of bladder sensation non-invasively. © 2013 Wiley Periodicals, Inc.

  10. Deployment Repeatability

    Science.gov (United States)

    2016-08-31

    large cohort of trials to spot unusual cases. However, deployment repeatability is inherently a nonlinear phenomenon, which makes modeling difficult...and GEMS tip position were both tracked during ground testing by a laser target tracking system. Earlier SAILMAST testing in 2005 [8] used...recalls the strategy used by SRTM, where a constellation of lights was installed at the tip of the boom and a modified star tracker was used to track tip

  11. REPEATING FAST RADIO BURSTS FROM HIGHLY MAGNETIZED PULSARS TRAVELING THROUGH ASTEROID BELTS

    International Nuclear Information System (INIS)

    Dai, Z. G.; Wang, J. S.; Huang, Y. F.; Wu, X. F.

    2016-01-01

    Very recently, Spitler et al. and Scholz et al. reported their detections of 16 additional bright bursts in the direction of the fast radio burst (FRB) 121102. This repeating FRB is inconsistent with all of the catastrophic event models put forward previously for hypothetically non-repeating FRBs. Here, we propose a different model, in which highly magnetized pulsars travel through the asteroid belts of other stars. We show that a repeating FRB could originate from such a pulsar encountering a large number of asteroids in the belt. During each pulsar-asteroid impact, an electric field induced outside of the asteroid has such a large component parallel to the stellar magnetic field that electrons are torn off the asteroidal surface and accelerated to ultra-relativistic energies instantaneously. The subsequent movement of these electrons along magnetic field lines will cause coherent curvature radiation, which can account for all of the properties of an FRB. In addition, this model can self-consistently explain the typical duration, luminosity, and repetitive rate of the 17 bursts of FRB 121102. The predicted occurrence rate of repeating FRB sources may imply that our model would be testable in the next few years.

  12. REPEATING FAST RADIO BURSTS FROM HIGHLY MAGNETIZED PULSARS TRAVELING THROUGH ASTEROID BELTS

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Z. G.; Wang, J. S.; Huang, Y. F. [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Wu, X. F., E-mail: dzg@nju.edu.cn [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

    2016-09-20

    Very recently, Spitler et al. and Scholz et al. reported their detections of 16 additional bright bursts in the direction of the fast radio burst (FRB) 121102. This repeating FRB is inconsistent with all of the catastrophic event models put forward previously for hypothetically non-repeating FRBs. Here, we propose a different model, in which highly magnetized pulsars travel through the asteroid belts of other stars. We show that a repeating FRB could originate from such a pulsar encountering a large number of asteroids in the belt. During each pulsar-asteroid impact, an electric field induced outside of the asteroid has such a large component parallel to the stellar magnetic field that electrons are torn off the asteroidal surface and accelerated to ultra-relativistic energies instantaneously. The subsequent movement of these electrons along magnetic field lines will cause coherent curvature radiation, which can account for all of the properties of an FRB. In addition, this model can self-consistently explain the typical duration, luminosity, and repetitive rate of the 17 bursts of FRB 121102. The predicted occurrence rate of repeating FRB sources may imply that our model would be testable in the next few years.

  13. Low-Normal FMR1 CGG Repeat Length: Phenotypic Associations

    Directory of Open Access Journals (Sweden)

    Marsha eMailick

    2014-09-01

    Full Text Available This population-based study investigates genotype-phenotype correlations of low-normal CGG repeats in the fragile X mental retardation 1 (FMR1 gene. FMR1 plays an important role in brain development and function, and encodes FMRP (fragile X mental retardation protein, an RNA-binding protein that regulates protein synthesis impacting activity-dependent synaptic development and plasticity. Most past research has focused on CGG premutation expansions (41 to 200 CGG repeats and on fragile X syndrome (200+ CGG repeats, with considerably less attention on the other end of the spectrum of CGG repeats. Using existing data, older adults with 23 or fewer CGG repeats (2 SDs below the mean were compared with age-peers who have normal numbers of CGGs (24-40 with respect to cognition, mental health, cancer, and having children with disabilities. Men (n = 341 with an allele in the low-normal range and women (n = 46 with two low-normal alleles had significantly more difficulty with their memory and ability to solve day to day problems. Women with both FMR1 alleles in the low-normal category had significantly elevated odds of feeling that they need to drink more to get the same effect as in the past. These women also had two and one-half times the odds of having had breast cancer and four times the odds of uterine cancer. Men and women with low-normal CGGs had higher odds of having a child with a disability, either a developmental disability or a mental health condition. These findings are in line with the hypothesis that there is a need for tight neuronal homeostatic control mechanisms for optimal cognitive and behavioral functioning, and more generally that low numbers as well as high numbers of CGG repeats may be problematic for health.

  14. Inverted repeats in the promoter as an autoregulatory sequence for TcrX in Mycobacterium tuberculosis

    International Nuclear Information System (INIS)

    Bhattacharya, Monolekha; Das, Amit Kumar

    2011-01-01

    Highlights: ► The regulatory sequences recognized by TcrX have been identified. ► The regulatory region comprises of inverted repeats segregated by 30 bp region. ► The mode of binding of TcrX with regulatory sequence is unique. ► In silico TcrX–DNA docked model binds one of the inverted repeats. ► Both phosphorylated and unphosphorylated TcrX binds regulatory sequence in vitro. -- Abstract: TcrY, a histidine kinase, and TcrX, a response regulator, constitute a two-component system in Mycobacterium tuberculosis. tcrX, which is expressed during iron scarcity, is instrumental in the survival of iron-dependent M. tuberculosis. However, the regulator of tcrX/Y has not been fully characterized. Crosslinking studies of TcrX reveal that it can form oligomers in vitro. Electrophoretic mobility shift assays (EMSAs) show that TcrX recognizes two regions in the promoter that are comprised of inverted repeats separated by ∼30 bp. The dimeric in silico model of TcrX predicts binding to one of these inverted repeat regions. Site-directed mutagenesis and radioactive phosphorylation indicate that D54 of TcrX is phosphorylated by H256 of TcrY. However, phosphorylated and unphosphorylated TcrX bind the regulatory sequence with equal efficiency, which was shown with an EMSA using the D54A TcrX mutant.

  15. R-loops: targets for nuclease cleavage and repeat instability.

    Science.gov (United States)

    Freudenreich, Catherine H

    2018-01-11

    R-loops form when transcribed RNA remains bound to its DNA template to form a stable RNA:DNA hybrid. Stable R-loops form when the RNA is purine-rich, and are further stabilized by DNA secondary structures on the non-template strand. Interestingly, many expandable and disease-causing repeat sequences form stable R-loops, and R-loops can contribute to repeat instability. Repeat expansions are responsible for multiple neurodegenerative diseases, including Huntington's disease, myotonic dystrophy, and several types of ataxias. Recently, it was found that R-loops at an expanded CAG/CTG repeat tract cause DNA breaks as well as repeat instability (Su and Freudenreich, Proc Natl Acad Sci USA 114, E8392-E8401, 2017). Two factors were identified as causing R-loop-dependent breaks at CAG/CTG tracts: deamination of cytosines and the MutLγ (Mlh1-Mlh3) endonuclease, defining two new mechanisms for how R-loops can generate DNA breaks (Su and Freudenreich, Proc Natl Acad Sci USA 114, E8392-E8401, 2017). Following R-loop-dependent nicking, base excision repair resulted in repeat instability. These results have implications for human repeat expansion diseases and provide a paradigm for how RNA:DNA hybrids can cause genome instability at structure-forming DNA sequences. This perspective summarizes mechanisms of R-loop-induced fragility at G-rich repeats and new links between DNA breaks and repeat instability.

  16. Effects of repeated collaborative retrieval on individual memory vary as a function of recall versus recognition tasks.

    Science.gov (United States)

    Blumen, Helena M; Rajaram, Suparna

    2009-11-01

    Our research examines how prior group collaboration modulates later individual memory. We recently showed that repeated collaborative recall sessions benefit later individual recall more than a single collaborative recall session (Blumen & Rajaram, 2008). Current research compared the effects of repeated collaborative recall and repeated collaborative recognition on later individual recall and later individual recognition. A total of 192 participants studied a list of nouns and then completed three successive retrieval sessions in one of four conditions. While two collaborative recall sessions and two collaborative recognition sessions generated comparable levels of individual recall (CRecall-CRecall-I Recall approximately CRecognition-CRecognition-I Recall , Experiment 1a), two collaborative recognition sessions generated greater levels of individual recognition than two collaborative recall sessions (CRecognition-CRecognition- IRecognition > CRecall-CRecall- I Recognition , Experiment 1b). These findings are discussed in terms of two opposing mechanisms that operate during collaborative retrieval-re-exposure and retrieval disruption-and in terms of transfer-appropriate processing across collaborative and individual retrieval sessions.

  17. Brain pathology after mild traumatic brain injury: an exploratory study by repeated magnetic resonance examination.

    Science.gov (United States)

    Lannsjö, Marianne; Raininko, Raili; Bustamante, Mariana; von Seth, Charlotta; Borg, Jörgen

    2013-09-01

    To explore brain pathology after mild traumatic brain injury by repeated magnetic resonance examination. A prospective follow-up study. Nineteen patients with mild traumatic brain injury presenting with Glasgow Coma Scale (GCS) 14-15. The patients were examined on day 2 or 3 and 3-7 months after the injury. The magnetic resonance protocol comprised conventional T1- and T2-weighted sequences including fluid attenuated inversion recovery (FLAIR), two susceptibility-weighted sequences to reveal haemorrhages, and diffusion-weighted sequences. Computer-aided volume comparison was performed. Clinical outcome was assessed by the Rivermead Post-Concussion Symptoms Questionnaire (RPQ), Hospital Anxiety and Depression Scale (HADS) and Glasgow Outcome Scale Extended (GOSE). At follow-up, 7 patients (37%) reported ≥  3 symptoms in RPQ, 5 reported some anxiety and 1 reported mild depression. Fifteen patients reported upper level of good recovery and 4 patients lower level of good recovery (GOSE 8 and 7, respectively). Magnetic resonance pathology was found in 1 patient at the first examination, but 4 patients (21%) showed volume loss at the second examination, at which 3 of them reported GOSE scores of 8. Loss of brain volume, demonstrated by computer-aided magnetic resonance imaging volumetry, may be a feasible marker of brain pathology after mild traumatic brain injury.

  18. Freely Chosen Index Finger Tapping Frequency Is Increased in Repeated Bouts of Tapping.

    Science.gov (United States)

    Hansen, Ernst Albin; Ebbesen, Brian Duborg; Dalsgaard, Ane; Mora-Jensen, Mark Holten; Rasmussen, Jakob

    2015-01-01

    Healthy individuals (n = 40) performed index finger tapping at freely chosen frequency during repeated bouts and before and after near-maximal muscle action consisting of 3 intense flexions of the index finger metacarpal phalangeal joint. One experiment showed, unexpectedly, that a bout of tapping increased the tapping frequency in the subsequent bout. Thus, a cumulating increase of 8.2 ± 5.4% (p tapping frequency was still increased in consecutive bouts when rest periods were extended to 20 min. Besides, near-maximal muscle activation, followed by 5 min rest, did not affect the tapping frequency. In conclusion, freely chosen tapping frequency was increased in repeated bouts of tapping, which were separated by 10-20 min rest periods. The observed phenomenon is suggested to be termed repeated bout rate enhancement.

  19. Are routine repeat chest x-rays before leaving the trauma room useful?

    NARCIS (Netherlands)

    Lemmers, M.; Saltzherr, T. P.; Beenen, L. F. M.; Ponsen, K. J.; Goslings, J. C.

    2010-01-01

    Several guidelines advocate multiple chest x-rays during primary resuscitation of trauma patients. Some local hospital protocols include a repeat x-ray before leaving the trauma resuscitation room (TR). The purpose of this study was to determine the value of routine repeat x-rays. One-year data of

  20. The value of repeating studies and multiple controls: replicated 28-day growth studies of rainbow trout exposed to clofibric acid.

    Science.gov (United States)

    Owen, Stewart F; Huggett, Duane B; Hutchinson, Thomas H; Hetheridge, Malcolm J; McCormack, Paul; Kinter, Lewis B; Ericson, Jon F; Constantine, Lisa A; Sumpter, John P

    2010-12-01

    Two studies to examine the effect of waterborne clofibric acid (CA) on growth-rate and condition of rainbow trout were conducted using accepted regulatory tests (Organisation for Economic Co-operation and Development [OECD] 215). The first study (in 2005) showed significant reductions after 21 d of exposure (21-d growth lowest-observed-effect concentration [LOEC] = 0.1 µg/L, 21-d condition LOEC = 0.1 µg/L) that continued to 28 d. Growth rate was reduced by approximately 50% (from 5.27 to 2.67% per day), while the condition of the fish reduced in a concentration-dependant manner. Additionally, in a concentration-dependent manner, significant changes in relative liver size were observed, such that increasing concentrations of CA resulted in smaller livers after 28-d exposure. A no-observed-effect concentration (NOEC) was not achieved in the 2005 study. An expanded second study (in 2006) that included a robust bridge to the 2005 study, with four replicate tanks of eight individual fish per concentration, did not repeat the 2005 findings. In the 2006 study, no significant effect on growth rate, condition, or liver biometry was observed after 21 or 28 d (28-d growth NOEC = 10 µg/L, 28-d condition NOEC = 10 µg/L), contrary to the 2005 findings. We do not dismiss either of these findings and suggest both are relevant and stand for comparison. However, the larger 2006 study carries more statistical power and multiple-tank replication, so probably produced the more robust findings. Despite sufficient statistical power in each study, interpretation of these and similar studies should be conducted with caution, because much significance is placed on the role of limited numbers of individual and tank replicates and the influence of control animals. Copyright © 2010 SETAC.

  1. Repeatability of chemical-shift-encoded water-fat MRI and diffusion-tensor imaging in lower extremity muscles in children.

    Science.gov (United States)

    Ponrartana, Skorn; Andrade, Kristine E; Wren, Tishya A L; Ramos-Platt, Leigh; Hu, Houchun H; Bluml, Stefan; Gilsanz, Vicente

    2014-06-01

    The purpose of this study was to assess the repeatability of water-fat MRI and diffusion-tensor imaging (DTI) as quantitative biomarkers of pediatric lower extremity skeletal muscle. MRI at 3 T of a randomly selected thigh and lower leg of seven healthy children was studied using water-fat separation and DTI techniques. Muscle-fat fraction, apparent diffusion coefficient (ADC), and fractional anisotropy (FA) values were calculated. Test-retest and interrater repeatability were assessed by calculating the Pearson correlation coefficient, intraclass correlation coefficient, and Bland-Altman analysis. Bland-Altman plots show that the mean difference between test-retest and interrater measurements of muscle-fat fraction, ADC, and FA was near 0. The correlation coefficients and intraclass correlation coefficients were all between 0.88 and 0.99 (p DTI measurements in lower extremity skeletal muscles are objective repeatable biomarkers in children. This knowledge should aid in the understanding of the number of participants needed in clinical trials when using these determinations as an outcome measure to noninvasively monitor neuromuscular disease.

  2. A CGG-repeat expansion mutation in ZNF713 causes FRA7A: association with autistic spectrum disorder in two families.

    Science.gov (United States)

    Metsu, Sofie; Rainger, Jacqueline K; Debacker, Kim; Bernhard, Birgitta; Rooms, Liesbeth; Grafodatskaya, Daria; Weksberg, Rosanna; Fombonne, Eric; Taylor, Martin S; Scherer, Stephen W; Kooy, R Frank; FitzPatrick, David R

    2014-11-01

    We report de novo occurrence of the 7p11.2 folate-sensitive fragile site FRA7A in a male with an autistic spectrum disorder (ASD) due to a CGG-repeat expansion mutation (∼450 repeats) in a 5' intron of ZNF713. This expanded allele showed hypermethylation of the adjacent CpG island with reduced ZNF713 expression observed in a proband-derived lymphoblastoid cell line (LCL). His unaffected mother carried an unmethylated premutation (85 repeats). This CGG-repeat showed length polymorphism in control samples (five to 22 repeats). In a second unrelated family, three siblings with ASD and their unaffected father were found to carry FRA7A premutations, which were partially or mosaically methylated. In one of the affected siblings, mitotic instability of the premutation was observed. ZNF713 expression in LCLs in this family was increased in three of these four premutation carriers. A firm link cannot yet be established between ASD and the repeat expansion mutation but plausible pathogenic mechanisms are discussed. © 2014 WILEY PERIODICALS, INC.

  3. Muscle Damage and Metabolic Responses to Repeated-Sprint Running With and Without Deceleration.

    Science.gov (United States)

    Minahan, Clare L; Poke, Daniel P; Morrison, Jaime; Bellinger, Phillip M

    2018-04-04

    Minahan, CL, Poke, DP, Morrison, J, and Bellinger, PM. Muscle damage and metabolic responses to repeated-sprint running with and without deceleration. J Strength Cond Res XX(X): 000-000, 2017-This study aimed to determine whether repeated-sprint running with deceleration aggravates markers of muscle damage or delays the recovery of performance compared with repeated-sprint running without deceleration. Fourteen male team-sport athletes performed 2 randomly ordered testing sessions on a nonmotorized treadmill with one session requiring participants to decelerate (TMd) within 4 seconds before stopping or immediately step to the side of the treadmill belt at the completion of each sprint (TMa). Peak and mean velocities, speed decrement, blood lactate concentrations, and oxygen uptake were monitored during the repeated-sprint running protocols. Countermovement vertical jump (CMJ) performance, perceived muscle soreness, sit-and-reach flexibility, plasma creatine kinase (CK), lactate dehydrogenase (LDH), and myoglobin (Mb) concentrations were quantified immediately before and after and 45 minutes, 24 and 48 hours after repeated-sprint running protocols. Although muscle damage was indicated by increases in CK, LDH, and Mb (p ≤ 0.05) in both groups, there was no significant effect of condition (TMa vs. TMd) on any of the measured performance or physiological variables (p > 0.05). The present study indicated that the removal of deceleration from repeated-sprint running on a nonmotorized treadmill has no effect on metabolism or performance during or after repeated-sprint running or markers of muscle damage.

  4. Potentials and limitations of histone repeat sequences for phylogenetic reconstruction of Sophophora.

    Science.gov (United States)

    Baldo, A M; Les, D H; Strausbaugh, L D

    1999-11-01

    Simplified DNA sequence acquisition has provided many new data sets that are useful for phylogenetic reconstruction, including single- and multiple-copy nuclear and organellar genes. Although transcribed regions receive much attention, nontranscribed regions have recently been added to the repertoire of sequences suitable for phylogenetic studies, especially for closely related taxa. We evaluated the efficacy of a small portion of the histone repeat for phylogenetic reconstruction among Drosophila species. Histone repeats in invertebrates offer distinct advantages similar to those of widely used ribosomal repeats. First, the units are tandemly repeated and undergo concerted evolution. Second, histone repeats include both highly conserved coding and variable intergenic regions. This composition facilitates application of "universal" primers spanning potentially informative sites. We examined a small region of the histone repeat, including the intergenic spacer segments of coding regions from the divergently transcribed H2A and H2B histone genes. The spacer (about 230 bp) exists as a mosaic with highly conserved functional motifs interspersed with rapidly diverging regions; the former aid in alignment of the spacer. There are no ambiguities in alignment of coding regions. Coding and noncoding regions were analyzed together and separately for phylogenetic information. Parsimony, distance, and maximum-likelihood methods successfully retrieve the corroborated phylogeny for the taxa examined. This study demonstrates the resolving power of a small histone region which may now be added to the growing collection of phylogenetically useful DNA sequences.

  5. Solution properties of the archaeal CRISPR DNA repeat-binding homeodomain protein Cbp2

    DEFF Research Database (Denmark)

    Kenchappa, Chandra; Heiðarsson, Pétur Orri; Kragelund, Birthe

    2013-01-01

    Clustered regularly interspaced short palindromic repeats (CRISPR) form the basis of diverse adaptive immune systems directed primarily against invading genetic elements of archaea and bacteria. Cbp1 of the crenarchaeal thermoacidophilic order Sulfolobales, carrying three imperfect repeats, binds...... specifically to CRISPR DNA repeats and has been implicated in facilitating production of long transcripts from CRISPR loci. Here, a second related class of CRISPR DNA repeat-binding protein, denoted Cbp2, is characterized that contains two imperfect repeats and is found amongst members of the crenarchaeal...... in facilitating high affinity DNA binding of Cbp2 by tethering the two domains. Structural studies on mutant proteins provide support for Cys(7) and Cys(28) enhancing high thermal stability of Cbp2(Hb) through disulphide bridge formation. Consistent with their proposed CRISPR transcriptional regulatory role, Cbp2...

  6. Risk factors for complications in donors at first and repeat whole blood donation: a cohort study with assessment of the impact on donor return.

    Science.gov (United States)

    Wiersum-Osselton, Johanna C; Marijt-van der Kreek, Tanneke; Brand, Anneke; Veldhuizen, Ingrid; van der Bom, Johanna G; de Kort, Wim

    2014-01-01

    First-time donation is among recognised risk factors for vasovagal reactions to blood donation and reactions are known to reduce donor return. We assessed associations between potential risk factors and vasovagal reactions and needle-related complications in first-time whole blood donation in comparison to repeat donation and analysed the impact of complications on donor return. We performed a cohort study on whole blood donations in The Netherlands from 1/1/2010 to 31/12/2010 using data extracted from the blood service information system. Donation data up to 31/12/2011 were used to ascertain donor return. In 2010 28,786 donors made first whole blood donations and there were 522,958 repeat donations. Vasovagal reactions occurred in 3.9% of first donations by males and 3.5% of first donations by females compared to in 0.2% and 0.6%, respectively, of repeat donations. Associations of vasovagal reactions with other factors including age, body weight, systolic and diastolic blood pressure were similar in first-time and repeat donors. Needle-related complications occurred in 0.2% of male and 0.5% of female first-time donations and in 0.1% and 0.3%, respectively, of repeat donations. Among first-time donors, the return rate within 1 year was 82% following an uncomplicated first donation, but 55% and 61% following vasovagal reactions and needle-related complications, respectively; the corresponding percentages among repeat donors were 86%, 58% and 82%. Among first-time donors, females suffered less than males from vasovagal reactions. Other risk factors had similar associations among first-time and repeat donors. Vasovagal reactions and needle-related complications in both first-time and repeat donors are followed by reduced donor return.

  7. Expression, purification and preliminary biochemical and structural characterization of the leucine rich repeat namesake domain of leucine rich repeat kinase 2.

    Science.gov (United States)

    Vancraenenbroeck, Renée; Lobbestael, Evy; Weeks, Stephen D; Strelkov, Sergei V; Baekelandt, Veerle; Taymans, Jean-Marc; De Maeyer, Marc

    2012-03-01

    Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common cause of familial Parkinson's disease. Much research effort has been directed towards the catalytic core region of LRRK2 composed of GTPase (ROC, Ras of complex proteins) and kinase domains and a connecting COR (C-terminus of ROC) domain. In contrast, the precise functions of the protein-protein interaction domains, such as the leucine-rich repeat (LRR) domain, are not known. In the present study, we modeled the LRRK2 LRR domain (LRR(LRRK2)) using a template assembly approach, revealing the presence of 14 LRRs. Next, we focused on the expression and purification of LRR(LRRK2) in Escherichia coli. Buffer optimization revealed that the protein requires the presence of a zwitterionic detergent, namely Empigen BB, during solubilization and the subsequent purification and characterization steps. This indicates that the detergent captures the hydrophobic surface patches of LRR(LRRK2) thereby suppressing its aggregation. Circular dichroism (CD) spectroscopy measured 18% α-helices and 21% β-sheets, consistent with predictions from the homology model. Size exclusion chromatography (SEC) and dynamic light scattering measurements showed the presence of a single species, with a Stokes radius corresponding to the model dimensions of a protein monomer. Furthermore, no obvious LRR(LRRK2) multimerization was detected via cross-linking studies. Finally, the LRR(LRRK2) clinical mutations did not influence LRR(LRRK2) secondary, tertiary or quaternary structure as determined via SEC and CD spectroscopy. We therefore conclude that these mutations are likely to affect putative LRR(LRRK2) inter- and intramolecular interactions. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Misleading Children: Causal Attributions of Inconsistency under Repeated Questioning.

    Science.gov (United States)

    Siegal, Michael; And Others

    1988-01-01

    Four studies investigated whether inconsistency of children aged four to six on developmental tasks may reflect a misinterpretation of the experimenter's intent in communication under repeated questioning. (SKC)

  9. Amyloid formation and disaggregation of α-synuclein and its tandem repeat (α-TR)

    International Nuclear Information System (INIS)

    Bae, Song Yi; Kim, Seulgi; Hwang, Heejin; Kim, Hyun-Kyung; Yoon, Hyun C.; Kim, Jae Ho; Lee, SangYoon; Kim, T. Doohun

    2010-01-01

    Research highlights: → Formation of the α-synuclein amyloid fibrils by [BIMbF 3 Im]. → Disaggregation of amyloid fibrils by epigallocatechin gallate (EGCG) and baicalein. → Amyloid formation of α-synuclein tandem repeat (α-TR). -- Abstract: The aggregation of α-synuclein is clearly related to the pathogenesis of Parkinson's disease. Therefore, detailed understanding of the mechanism of fibril formation is highly valuable for the development of clinical treatment and also of the diagnostic tools. Here, we have investigated the interaction of α-synuclein with ionic liquids by using several biochemical techniques including Thioflavin T assays and transmission electron microscopy (TEM). Our data shows a rapid formation of α-synuclein amyloid fibrils was stimulated by 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [BIMbF 3 Im], and these fibrils could be disaggregated by polyphenols such as epigallocatechin gallate (EGCG) and baicalein. Furthermore, the effect of [BIMbF 3 Im] on the α-synuclein tandem repeat (α-TR) in the aggregation process was studied.

  10. Joint Ordering and Pricing Decisions for New Repeat-Purchase Products

    OpenAIRE

    Wu, Xiang; Zhang, Jinlong

    2015-01-01

    This paper studies ordering and pricing problems for new repeat-purchase products. We incorporate the repeat-purchase rate and price effects into the Bass model to characterize the demand pattern. We consider two decision models: (1) two-stage decision model, in which the sales division chooses a price to maximize the gross profit and the purchasing division determines an optimal ordering decision to minimize the total cost under a given demand subsequently, and (2) joint decision model, in w...

  11. Rate, correlates and outcomes of repeat pregnancy in HIV-infected women.

    Science.gov (United States)

    Floridia, M; Tamburrini, E; Masuelli, G; Martinelli, P; Spinillo, A; Liuzzi, G; Vimercati, A; Alberico, S; Maccabruni, A; Pinnetti, C; Frisina, V; Dalzero, S; Ravizza, M

    2017-07-01

    The aim of the study was to assess the rate, determinants, and outcomes of repeat pregnancies in women with HIV infection. Data from a national study of pregnant women with HIV infection were used. Main outcomes were preterm delivery, low birth weight, CD4 cell count and HIV plasma viral load. The rate of repeat pregnancy among 3007 women was 16.2%. Women with a repeat pregnancy were on average younger than those with a single pregnancy (median age 30 vs. 33 years, respectively), more recently diagnosed with HIV infection (median time since diagnosis 25 vs. 51 months, respectively), and more frequently of foreign origin [odds ratio (OR) 1.36; 95% confidence interval (CI) 1.10-1.68], diagnosed with HIV infection in the current pregnancy (OR: 1.69; 95% CI: 1.35-2.11), and at their first pregnancy (OR: 1.33; 95% CI: 1.06-1.66). In women with sequential pregnancies, compared with the first pregnancy, several outcomes showed a significant improvement in the second pregnancy, with a higher rate of antiretroviral treatment at conception (39.0 vs. 65.4%, respectively), better median maternal weight at the start of pregnancy (60 vs. 61 kg, respectively), a higher rate of end-of-pregnancy undetectable HIV RNA (60.7 vs. 71.6%, respectively), a higher median birth weight (2815 vs. 2885 g, respectively), lower rates of preterm delivery (23.0 vs. 17.7%, respectively) and of low birth weight (23.4 vs. 15.4%, respectively), and a higher median CD4 cell count (+47 cells/μL), with almost no clinical progression to Centers for Disease Control and Prevention stage C (CDC-C) HIV disease (0.3%). The second pregnancy was significantly more likely to end in voluntary termination than the first pregnancy (11.4 vs. 6.1%, respectively). Younger and foreign women were more likely to have a repeat pregnancy; in women with sequential pregnancies, the second pregnancy was characterized by a significant improvement in several outcomes, suggesting that women with HIV infection who desire multiple

  12. Intelligence is in the eye of the beholder: investigating repeated IQ measurements in forensic psychiatry.

    Science.gov (United States)

    Habets, Petra; Jeandarme, Inge; Uzieblo, Kasia; Oei, Karel; Bogaerts, Stefan

    2015-05-01

    A stable assessment of cognition is of paramount importance for forensic psychiatric patients (FPP). The purpose of this study was to compare repeated measures of IQ scores in FPPs with and without intellectual disability. Repeated measurements of IQ scores in FPPs (n = 176) were collected. Differences between tests were computed, and each IQ score was categorized. Additionally, t-tests and regression analyses were performed. Differences of 10 points or more were found in 66% of the cases comparing WAIS-III with RAVEN scores. Fisher's exact test revealed differences between two WAIS-III scores and the WAIS categories. The WAIS-III did not predict other IQs (WAIS or RAVEN) in participants with intellectual disability. This study showed that stability or interchangeability of scores is lacking, especially in individuals with intellectual disability. Caution in interpreting IQ scores is therefore recommended, and the use of the unitary concept of IQ should be discouraged. © 2014 John Wiley & Sons Ltd.

  13. The energy landscapes of repeat-containing proteins: topology, cooperativity, and the folding funnels of one-dimensional architectures.

    Directory of Open Access Journals (Sweden)

    Diego U Ferreiro

    2008-05-01

    Full Text Available Repeat-proteins are made up of near repetitions of 20- to 40-amino acid stretches. These polypeptides usually fold up into non-globular, elongated architectures that are stabilized by the interactions within each repeat and those between adjacent repeats, but that lack contacts between residues distant in sequence. The inherent symmetries both in primary sequence and three-dimensional structure are reflected in a folding landscape that may be analyzed as a quasi-one-dimensional problem. We present a general description of repeat-protein energy landscapes based on a formal Ising-like treatment of the elementary interaction energetics in and between foldons, whose collective ensemble are treated as spin variables. The overall folding properties of a complete "domain" (the stability and cooperativity of the repeating array can be derived from this microscopic description. The one-dimensional nature of the model implies there are simple relations for the experimental observables: folding free-energy (DeltaG(water and the cooperativity of denaturation (m-value, which do not ordinarily apply for globular proteins. We show how the parameters for the "coarse-grained" description in terms of foldon spin variables can be extracted from more detailed folding simulations on perfectly funneled landscapes. To illustrate the ideas, we present a case-study of a family of tetratricopeptide (TPR repeat proteins and quantitatively relate the results to the experimentally observed folding transitions. Based on the dramatic effect that single point mutations exert on the experimentally observed folding behavior, we speculate that natural repeat proteins are "poised" at particular ratios of inter- and intra-element interaction energetics that allow them to readily undergo structural transitions in physiologically relevant conditions, which may be intrinsically related to their biological functions.

  14. Study of damage of graphite/epoxy composites submitted to repeated quasi-static shear loadings

    International Nuclear Information System (INIS)

    Khadhraoui-Lattreche, Malika

    1984-01-01

    Quasi static loading tests on composite materials with organic matrix allow the behaviour of the materials under repeated loadings to be studied while avoiding viscoelastic effects. In this research thesis, the author reports the study of one-directional composite samples submitted to static pure shear loadings which represent the most severe stress state for this type of material. The material behaviour has been determined by application of loads greater than the yield strength, and of zero torque unloads. This allowed cumulative residual deformations to be monitored, and the increasing evolution of this parameter to be studied with respect to the number of applied cycles. The author deduces from these results a characteristic law for the material which introduces a decoupling between the stress and the cumulative residual deformation. Thus, a method of prediction of cumulative residual deformations is developed. Besides, a brief application to another material seems to confirm this type of law, and suggests that its generalisation should be studied [fr

  15. No impact of repeated extinction exposures on operant responding maintained by different reinforcer rates.

    Science.gov (United States)

    Bai, John Y H; Podlesnik, Christopher A

    2017-05-01

    Greater rates of intermittent reinforcement in the presence of discriminative stimuli generally produce greater resistance to extinction, consistent with predictions of behavioral momentum theory. Other studies reveal more rapid extinction with higher rates of reinforcers - the partial reinforcement extinction effect. Further, repeated extinction often produces more rapid decreases in operant responding due to learning a discrimination between training and extinction contingencies. The present study examined extinction repeatedly with training with different rates of intermittent reinforcement in a multiple schedule. We assessed whether repeated extinction would reverse the pattern of greater resistance to extinction with greater reinforcer rates. Counter to this prediction, resistance to extinction was consistently greater across twelve assessments of training followed by six successive sessions of extinction. Moreover, patterns of responding during extinction resembled those observed during satiation tests, which should not alter discrimination processes with repeated testing. These findings join others suggesting operant responding in extinction can be durable across repeated tests. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. The flow Rate Accuracy of Elastomeric Infusion Pumps After Repeated Filling.

    Science.gov (United States)

    Mohseni, Masood; Ebneshahidi, Amin

    2014-05-01

    One of the frequent applications of elastomeric infusion pumps is postoperative pain management. In daily practice, the disposable pumps get refilled with modified medication combinations in the successive days; although, the accuracy of infusion rates is unknown to clinicians. Our aim was to evaluate the effect of repeated filling on the delivery rate accuracy of an elastomeric pump available in our market. We examined 10 elastomeric infusion pumps (BOT-802, Nanchang Biotek Medical Device Company, China) with 100 mL capacity and nominal flow of 5 mL/h. Each pump was filled for three times, accounting for 30 series of experiments. A microset scaled in mL was used to measure the pump deliveries. Flow profile and reliability of infusion rate were analyzed after repeated use. The mean flow rate in the three series of measurements showed a gradual increase; however, the difference was not statistically significant (5.01 ± 0.07 vs. 5.03 ± 0.06 vs. 5.06 ± 0.08 mL/h; P = 0.81). The percentage of the flow rate error (deviation from 5 mL/h ± 15%) was 100% in the first and second hours of infusion, 96% in the third hour, 60% in the 20th hour and zero percent in the rest of the infusion time. This study indicated that the delivery rate accuracy of elastomeric infusion pumps is preserved after repeated usage. These laboratory findings suggested that elastomeric pumps could be safely refilled in the successive days to provide postoperative analgesia.

  17. Repeated irradiations with γ-rays at a dose of 0.5 Gy may exacerbate asthma

    International Nuclear Information System (INIS)

    Fang, Su-ping; Tago, Fumitoshi; Tanaka, Takashi; Simura, Noriko; Kojima, Shuji; Muto, Yasuko; Goto, Resuke

    2005-01-01

    We previously showed that 0.5 Gy whole-body γ-ray irradiation with a single or small number of repeated exposures inhibits tumor growth in mice, via elevation of the IFNγ/IL-4 ratio concomitantly with a decrease in the percentage of B cells. Here we examined whether repeated 0.5 Gy γ-rays irradiation can improve asthma in an ovalbumin (OVA)-induced asthmatic mouse model. We found that repeated irradiation (10 times) with 0.5 Gy of γ-rays significantly increased total IgE in comparison with the disease-control group. The levels of IL-4 and IL-5 were also significantly higher in the γ-ray-irradiated group, while that of IFN-γ was significantly lower, resulting in a further decrease of the IFN-γ/IL-4 ratio from the normal value. These results indicate that the repeated irradiation with γ-rays may exacerbate asthma, and may have opposite effects on different immune reactions unlike the irradiation with a single or small number of repeated exposures. (author)

  18. Secondary immune response of rainbow trout following repeated immersion vaccination

    DEFF Research Database (Denmark)

    Jaafar, R. M.; Al-Jubury, A.; Chettri, J. K.

    2017-01-01

    Teleosts are able to raise a protective immune response, comprising both innate and adaptive elements, against various pathogens. This is the basis for a widespread use of vaccines, administered as injection or immersion, in the aquaculture industry. It has been described that repeated injection...... vaccination of fish raises a secondary immune response, consisting of rapid, accelerated and increased antibody reaction. This study reports how rainbow trout responds to repeated immersion vaccination against yersiniosis (ERM) caused by the bacterial pathogen Yersinia ruckeri. It was found that rainbow trout...... does not raise a classical secondary response following repeated immersion vaccination. Serum antibody titres were merely slightly increased even after three immunizations, using 30-s immersion into a bacterin consisting of formalin-inactivated Y. ruckeri (serotype O1, biotypes 1 and 2), performed over...

  19. Secondary immune response of rainbow trout following repeated immersion vaccination

    DEFF Research Database (Denmark)

    Jaafar, R. M.; Al-Jubury, Azmi; Chettri, Jiwan Kumar

    2018-01-01

    Teleosts are able to raise a protective immune response, comprising both innate and adaptive elements, against various pathogens. This is the basis for a widespread use of vaccines, administered as injection or immersion, in the aquaculture industry. It has been described that repeated injection...... vaccination of fish raises a secondary immune response, consisting of rapid, accelerated and increased antibody reaction. This study reports how rainbow trout responds to repeated immersion vaccination against yersiniosis (ERM) caused by the bacterial pathogen Yersinia ruckeri. It was found that rainbow trout...... does not raise a classical secondary response following repeated immersion vaccination. Serum antibody titres were merely slightly increased even after three immunizations, using 30-s immersion into a bacterin consisting of formalin-inactivated Y. ruckeri (serotype O1, biotypes 1 and 2), performed over...

  20. Analysis of real-time mixture cytotoxicity data following repeated exposure using BK/TD models.

    Science.gov (United States)

    Teng, S; Tebby, C; Barcellini-Couget, S; De Sousa, G; Brochot, C; Rahmani, R; Pery, A R R

    2016-08-15

    Cosmetic products generally consist of multiple ingredients. Thus, cosmetic risk assessment has to deal with mixture toxicity on a long-term scale which means it has to be assessed in the context of repeated exposure. Given that animal testing has been banned for cosmetics risk assessment, in vitro assays allowing long-term repeated exposure and adapted for in vitro - in vivo extrapolation need to be developed. However, most in vitro tests only assess short-term effects and consider static endpoints which hinder extrapolation to realistic human exposure scenarios where concentration in target organs is varies over time. Thanks to impedance metrics, real-time cell viability monitoring for repeated exposure has become possible. We recently constructed biokinetic/toxicodynamic models (BK/TD) to analyze such data (Teng et al., 2015) for three hepatotoxic cosmetic ingredients: coumarin, isoeugenol and benzophenone-2. In the present study, we aim to apply these models to analyze the dynamics of mixture impedance data using the concepts of concentration addition and independent action. Metabolic interactions between the mixture components were investigated, characterized and implemented in the models, as they impacted the actual cellular exposure. Indeed, cellular metabolism following mixture exposure induced a quick disappearance of the compounds from the exposure system. We showed that isoeugenol substantially decreased the metabolism of benzophenone-2, reducing the disappearance of this compound and enhancing its in vitro toxicity. Apart from this metabolic interaction, no mixtures showed any interaction, and all binary mixtures were successfully modeled by at least one model based on exposure to the individual compounds. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Human immunodeficiency virus long terminal repeat responds to T-cell activation signals

    International Nuclear Information System (INIS)

    Tong-Starksen, S.E.; Luciw, P.A.; Peterlin, B.M.

    1987-01-01

    Human immunodeficiency virus (HIV), the causative agent of AIDS, infects and kills lymphoid cells bearing the CD4 antigen. In an infected cell, a number of cellular as well as HIV-encoded gene products determine the levels of viral gene expression and HIV replication. Efficient HIV replication occurs in activated T cells. Utilizing transient expression assays, the authors show that gene expression directed by the HIV long terminal repeat (LTR) increases in response to T-cell activation signals. The effects of T-cell activation and of the HIV-encoded trans-activator (TAT) are multiplicative. Analysis of mutations and deletions in the HIV LTR reveals that the region responding to T-cell activation signals is located at positions -105 to -80. These sequences are composed of two direct repeats, which are homologous to the core transcriptional enhancer elements in the simian virus 40 genome. The studies reveal that these elements function as the HIV enhancer. By acting directly on the HIV LTR, T-cell activation may play an important role in HIV gene expression and in the activation of latent HIV

  2. Comparative Analysis of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) of Streptococcus thermophilus St-I and its Bacteriophage-Insensitive Mutants (BIM) Derivatives.

    Science.gov (United States)

    Li, Wan; Bian, Xin; Evivie, Smith Etareri; Huo, Gui-Cheng

    2016-09-01

    The CRISPR-Cas (CRISPR together with CRISPR-associated proteins) modules are the adaptive immune system, acting as an adaptive and heritable immune system in bacteria and archaea. CRISPR-based immunity acts by integrating short virus sequences in the cell's CRISPR locus, allowing the cell to remember, recognize, and clear infections. In this study, the homology of CRISPRs sequence in BIMs (bacteriophage-insensitive mutants) of Streptococcus thermophilus St-I were analyzed. Secondary structures of the repeats and the PAMs (protospacer-associated motif) of each CRISPR locus were also predicted. Results showed that CRISPR1 has 27 repeat-spacer units, 5 of them had duplicates; CRISPR2 has one repeat-spacer unit; CRISPR3 has 28 repeat-spacer units. Only BIM1 had a new spacer acquisition in CRISPR3, while BIM2 and BIM3 had no new spacers' insertion, thus indicating that while most CRISPR1 were more active than CRISPR3, new spacer acquisition occurred just in CRSPR3 in some situations. These findings will help establish the foundation for the study of CRSPR-Cas systems in lactic acid bacteria.

  3. Development of analog watch with minute repeater

    Science.gov (United States)

    Okigami, Tomio; Aoyama, Shigeru; Osa, Takashi; Igarashi, Kiyotaka; Ikegami, Tomomi

    A complementary metal oxide semiconductor with large scale integration was developed for an electronic minute repeater. It is equipped with the synthetic struck sound circuit to generate natural struck sound necessary for the minute repeater. This circuit consists of an envelope curve drawing circuit, frequency mixer, polyphonic mixer, and booster circuit made by using analog circuit technology. This large scale integration is a single chip microcomputer with motor drivers and input ports in addition to the synthetic struck sound circuit, and it is possible to make an electronic system of minute repeater at a very low cost in comparison with the conventional type.

  4. Twisting right to left: A…A mismatch in a CAG trinucleotide repeat overexpansion provokes left-handed Z-DNA conformation.

    Directory of Open Access Journals (Sweden)

    Noorain Khan

    2015-04-01

    Full Text Available Conformational polymorphism of DNA is a major causative factor behind several incurable trinucleotide repeat expansion disorders that arise from overexpansion of trinucleotide repeats located in coding/non-coding regions of specific genes. Hairpin DNA structures that are formed due to overexpansion of CAG repeat lead to Huntington's disorder and spinocerebellar ataxias. Nonetheless, DNA hairpin stem structure that generally embraces B-form with canonical base pairs is poorly understood in the context of periodic noncanonical A…A mismatch as found in CAG repeat overexpansion. Molecular dynamics simulations on DNA hairpin stems containing A…A mismatches in a CAG repeat overexpansion show that A…A dictates local Z-form irrespective of starting glycosyl conformation, in sharp contrast to canonical DNA duplex. Transition from B-to-Z is due to the mechanistic effect that originates from its pronounced nonisostericity with flanking canonical base pairs facilitated by base extrusion, backbone and/or base flipping. Based on these structural insights we envisage that such an unusual DNA structure of the CAG hairpin stem may have a role in disease pathogenesis. As this is the first study that delineates the influence of a single A…A mismatch in reversing DNA helicity, it would further have an impact on understanding DNA mismatch repair.

  5. Repeated speech errors: evidence for learning.

    Science.gov (United States)

    Humphreys, Karin R; Menzies, Heather; Lake, Johanna K

    2010-11-01

    Three experiments elicited phonological speech errors using the SLIP procedure to investigate whether there is a tendency for speech errors on specific words to reoccur, and whether this effect can be attributed to implicit learning of an incorrect mapping from lemma to phonology for that word. In Experiment 1, when speakers made a phonological speech error in the study phase of the experiment (e.g. saying "beg pet" in place of "peg bet") they were over four times as likely to make an error on that same item several minutes later at test. A pseudo-error condition demonstrated that the effect is not simply due to a propensity for speakers to repeat phonological forms, regardless of whether or not they have been made in error. That is, saying "beg pet" correctly at study did not induce speakers to say "beg pet" in error instead of "peg bet" at test. Instead, the effect appeared to be due to learning of the error pathway. Experiment 2 replicated this finding, but also showed that after 48 h, errors made at study were no longer more likely to reoccur. As well as providing constraints on the longevity of the effect, this provides strong evidence that the error reoccurrences observed are not due to item-specific difficulty that leads individual speakers to make habitual mistakes on certain items. Experiment 3 showed that the diminishment of the effect 48 h later is not due to specific extra practice at the task. We discuss how these results fit in with a larger view of language as a dynamic system that is constantly adapting in response to experience. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. Repeated isoflurane exposure and neuroapoptosis in the midgestation fetal sheep brain.

    Science.gov (United States)

    Olutoye, Olutoyin A; Sheikh, Fariha; Zamora, Irving J; Yu, Ling; Akinkuotu, Adesola C; Adesina, Adekunle M; Olutoye, Oluyinka O

    2016-04-01

    Advances in surgery and technology have resulted in increased in-utero procedures. However, the effect of anesthesia on the fetal brain is not fully known. The inhalational anesthetic agent, isoflurane, other gamma amino butyric acid agonists (benzodiazepines, barbiturates, propofol, other inhalation anesthetics), and N-methyl D aspartate antagonists, eg, ketamine, have been shown to induce neuroapoptosis. The ovine model has been used extensively to study maternal-fetal physiologic interactions and to investigate different surgical interventions on the fetus. The purpose of this study was to determine effects of different doses and duration of isoflurane on neuroapoptosis in midgestation fetal sheep. We hypothesized that repeated anesthetic exposure and high concentrations of isoflurane would result in increased neuroapoptosis. Time-dated, pregnant sheep at 70 days gestation (term 145 days) received either isoflurane 2% × 1 hour, 4% × 3 hours, or 2% × 1 hour every other day for 3 exposures (repeated exposure group). Euthanasia occurred following anesthetic exposure and fetal brains were processed. Neuroapoptosis was detected by immunohistochemistry using anticaspase-3 antibodies. Fetuses unexposed to anesthesia served as controls. Another midgestation group with repeated 2% isoflurane exposure was examined at day 130 (long-term group) and neuronal cell density compared to age-matched controls. Representative sections of the brain were analyzed using Aperio Digital imaging (Leica Microsystems Inc, Buffalo Grove, IL). Data, reported by number of neurons per cubic millimeter of brain tissue are presented as means and SEM. Data were analyzed using the Mann-Whitney U and Kruskal-Wallis tests as appropriate. A total of 34 fetuses were studied. There was no significant difference in neuroapoptosis observed in fetuses exposed to 2% isoflurane for 1 hour or 4% isoflurane for 3 hours. Increased neuroapoptosis was observed in the frontal cortex following repeated 2

  7. The Role of Repeated Exposure to Multimodal Input in Incidental Acquisition of Foreign Language Vocabulary.

    Science.gov (United States)

    Bisson, Marie-Josée; van Heuven, Walter J B; Conklin, Kathy; Tunney, Richard J

    2014-12-01

    Prior research has reported incidental vocabulary acquisition with complete beginners in a foreign language (FL), within 8 exposures to auditory and written FL word forms presented with a picture depicting their meaning. However, important questions remain about whether acquisition occurs with fewer exposures to FL words in a multimodal situation and whether there is a repeated exposure effect. Here we report a study where the number of exposures to FL words in an incidental learning phase varied between 2, 4, 6, and 8 exposures. Following the incidental learning phase, participants completed an explicit learning task where they learned to recognize written translation equivalents of auditory FL word forms, half of which had occurred in the incidental learning phase. The results showed that participants performed better on the words they had previously been exposed to, and that this incidental learning effect occurred from as little as 2 exposures to the multimodal stimuli. In addition, repeated exposure to the stimuli was found to have a larger impact on learning during the first few exposures and decrease thereafter, suggesting that the effects of repeated exposure on vocabulary acquisition are not necessarily constant.

  8. Effects of Repeated-Sprint Training in Hypoxia on Sea-Level Performance: A Meta-Analysis.

    Science.gov (United States)

    Brocherie, Franck; Girard, Olivier; Faiss, Raphaël; Millet, Grégoire P

    2017-08-01

    Repeated-sprint training in hypoxia (RSH) is a recent intervention regarding which numerous studies have reported effects on sea-level physical performance outcomes that are debated. No previous study has performed a meta-analysis of the effects of RSH. We systematically reviewed the literature and meta-analyzed the effects of RSH versus repeated-sprint training in normoxia (RSN) on key components of sea-level physical performance, i.e., best and mean (all sprint) performance during repeated-sprint exercise and aerobic capacity (i.e., maximal oxygen uptake [[Formula: see text

  9. MSDB: A Comprehensive Database of Simple Sequence Repeats.

    Science.gov (United States)

    Avvaru, Akshay Kumar; Saxena, Saketh; Sowpati, Divya Tej; Mishra, Rakesh Kumar

    2017-06-01

    Microsatellites, also known as Simple Sequence Repeats (SSRs), are short tandem repeats of 1-6 nt motifs present in all genomes, particularly eukaryotes. Besides their usefulness as genome markers, SSRs have been shown to perform important regulatory functions, and variations in their length at coding regions are linked to several disorders in humans. Microsatellites show a taxon-specific enrichment in eukaryotic genomes, and some may be functional. MSDB (Microsatellite Database) is a collection of >650 million SSRs from 6,893 species including Bacteria, Archaea, Fungi, Plants, and Animals. This database is by far the most exhaustive resource to access and analyze SSR data of multiple species. In addition to exploring data in a customizable tabular format, users can view and compare the data of multiple species simultaneously using our interactive plotting system. MSDB is developed using the Django framework and MySQL. It is freely available at http://tdb.ccmb.res.in/msdb. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  10. Abortion trends from 1996 to 2011 in Estonia: special emphasis on repeat abortion

    Science.gov (United States)

    2014-01-01

    Background The study aimed to describe the overall and age-specific trends of induced abortions from 1996 to 2011 with an emphasis on socio-demographic characteristics and contraceptive use of women having had repeat abortions in Estonia. Methods Data were retrieved from the Estonian Medical Birth and Abortion Registry and Statistics Estonia. Total induced abortion numbers, rates, ratios and age-specific rates are presented for 1996–2011. The percentage change in the number of repeat abortions within selected socio-demographic subgroups, contraception use and distribution of induced abortions among Estonians and non-Estonians for the first, second, third, fourth and subsequent abortions were calculated for the periods 1996–2003 and 2004–2011. Results Observed trends over the 16-year study period indicated a considerable decline in induced abortions with a reduction in abortion rate of 57.1%, which was mainly attributed to younger cohorts. The percentage of women undergoing repeat abortions fell steadily from 63.8% during 1996–2003 to 58.0% during 2004–2011. The percentage of women undergoing repeat abortions significantly decreased over the 16 years within all selected socio-demographic subgroups except among women with low educational attainment and students. Within each time period, a greater percentage of non-Estonians than Estonians underwent repeat abortions and obtained third and subsequent abortions. Most women did not use any contraceptive method prior to their first or subsequent abortion. Conclusion A high percentage of women obtaining repeat abortions reflects a high historical abortion rate. If current trends continue, a rapid decline in repeat abortions may be predicted. To decrease the burden of sexual ill health, routine contraceptive counselling, as standard care in the abortion process, should be seriously addressed with an emphasis on those groups - non-Estonians, women with lower educational attainment, students and women with children

  11. Impact of short‐term, repeated water fasting on the weight of mice

    Directory of Open Access Journals (Sweden)

    Zahra Mishmast

    2014-09-01

    Full Text Available Introduction: Caloric restriction is a strategy applied for weight loss. Water fasting is a popular way for obesity treatment. However, little is known about the impact of water fasting on weight. Therefore, this study was conducted to investigate the effect of short-term, repeated water fasting on the weight of mice. Methods: In this study, the physiological effect of short-term, repeated water fasting on the weight of female mice was evaluated. At 6 weeks of age, mice were randomly assigned to either repeated-fasting or control group (fed ad libitum. Each group consisted of twenty mice. As the fasting period started, the repeated-fasting group had access to only water; animals had free access to food and water on non-fasting days. Body weight of each group before, during, and after the fasting period was recorded. Results: Body weight of the fasting group significantly decreased, unlike the control group. However, the fasting group gained weight rapidly after being re-fed and became significantly heavier than mice in the control group (P

  12. Transcription arrest by a G quadruplex forming-trinucleotide repeat sequence from the human c-myb gene.

    Science.gov (United States)

    Broxson, Christopher; Beckett, Joshua; Tornaletti, Silvia

    2011-05-17

    Non canonical DNA structures correspond to genomic regions particularly susceptible to genetic instability. The transcription process facilitates formation of these structures and plays a major role in generating the instability associated with these genomic sites. However, little is known about how non canonical structures are processed when encountered by an elongating RNA polymerase. Here we have studied the behavior of T7 RNA polymerase (T7RNAP) when encountering a G quadruplex forming-(GGA)(4) repeat located in the human c-myb proto-oncogene. To make direct correlations between formation of the structure and effects on transcription, we have taken advantage of the ability of the T7 polymerase to transcribe single-stranded substrates and of G4 DNA to form in single-stranded G-rich sequences in the presence of potassium ions. Under physiological KCl concentrations, we found that T7 RNAP transcription was arrested at two sites that mapped to the c-myb (GGA)(4) repeat sequence. The extent of arrest did not change with time, indicating that the c-myb repeat represented an absolute block and not a transient pause to T7 RNAP. Consistent with G4 DNA formation, arrest was not observed in the absence of KCl or in the presence of LiCl. Furthermore, mutations in the c-myb (GGA)(4) repeat, expected to prevent transition to G4, also eliminated the transcription block. We show T7 RNAP arrest at the c-myb repeat in double-stranded DNA under conditions mimicking the cellular concentration of biomolecules and potassium ions, suggesting that the G4 structure formed in the c-myb repeat may represent a transcription roadblock in vivo. Our results support a mechanism of transcription-coupled DNA repair initiated by arrest of transcription at G4 structures.

  13. On balanced minimal repeated measurements designs

    Directory of Open Access Journals (Sweden)

    Shakeel Ahmad Mir

    2014-10-01

    Full Text Available Repeated Measurements designs are concerned with scientific experiments in which each experimental unit is assigned more than once to a treatment either different or identical. This class of designs has the property that the unbiased estimators for elementary contrasts among direct and residual effects are obtainable. Afsarinejad (1983 provided a method of constructing balanced Minimal Repeated Measurements designs p < t , when t is an odd or prime power, one or more than one treatment may occur more than once in some sequences and  designs so constructed no longer remain uniform in periods. In this paper an attempt has been made to provide a new method to overcome this drawback. Specifically, two cases have been considered                RM[t,n=t(t-t/(p-1,p], λ2=1 for balanced minimal repeated measurements designs and  RM[t,n=2t(t-t/(p-1,p], λ2=2 for balanced  repeated measurements designs. In addition , a method has been provided for constructing              extra-balanced minimal designs for special case RM[t,n=t2/(p-1,p], λ2=1.

  14. The Effects of Repeated Exposure to Graphic Fear Appeals on Cigarette Packages: A Field Experiment

    NARCIS (Netherlands)

    Dijkstra, A.; Bos, C.

    2015-01-01

    Experimental studies on the effects of graphic fear appeals on cigarette packages typically expose smokers in a single session to a fear appeal, although in practice the exposure is always repeated. The present study applied an improved study design with repeated exposure to fear appeals on

  15. The Effects of Repeated Exposure to Graphic Fear Appeals on Cigarette Packages : A Field Experiment

    NARCIS (Netherlands)

    Dijkstra, Arie; Colin, Bos,

    2015-01-01

    Experimental studies on the effects of graphic fear appeals on cigarette packages typically expose smokers in a single session to a fear appeal, although in practice the exposure is always repeated. The present study applied an improved study design with repeated exposure to fear appeals on

  16. Cytogenetic Diversity of Simple Sequences Repeats in Morphotypes of Brassica rapa ssp. chinensis.

    Science.gov (United States)

    Zheng, Jin-Shuang; Sun, Cheng-Zhen; Zhang, Shu-Ning; Hou, Xi-Lin; Bonnema, Guusje

    2016-01-01

    A significant fraction of the nuclear DNA of all eukaryotes is comprised of simple sequence repeats (SSRs). Although these sequences are widely used for studying genetic variation, linkage mapping and evolution, little attention had been paid to the chromosomal distribution and cytogenetic diversity of these sequences. In this paper, we report the distribution characterization of mono-, di-, and tri-nucleotide SSRs in Brassica rapa ssp. chinensis. Fluorescence in situ hybridization was used to characterize the cytogenetic diversity of SSRs among morphotypes of B. rapa ssp. chinensis. The proportion of different SSR motifs varied among morphotypes of B. rapa ssp. chinensis, with tri-nucleotide SSRs being more prevalent in the genome of B. rapa ssp. chinensis. We determined the chromosomal locations of mono-, di-, and tri-nucleotide repeat loci. The results showed that the chromosomal distribution of SSRs in the different morphotypes is non-random and motif-dependent, and allowed us to characterize the relative variability in terms of SSR numbers and similar chromosomal distributions in centromeric/peri-centromeric heterochromatin. The differences between SSR repeats with respect to abundance and distribution indicate that SSRs are a driving force in the genomic evolution of B. rapa species. Our results provide a comprehensive view of the SSR sequence distribution and evolution for comparison among morphotypes B. rapa ssp. chinensis.

  17. Study of problems associated with the ultrasonic examination of repeatedly repaired austenitic stainless steel welds

    International Nuclear Information System (INIS)

    Subbaratnam, R.; Palaniappan, M.; Baskaran, A.; Chandramohan, R.

    1994-01-01

    In recent years the ultrasonic examination of austenitic stainless steel weldments has gained increased importance as an NDE technique for the volumetric examination in the nuclear power plant construction and other industries. A study has been undertaken to evaluate the effects of multiple repairs on austenitic stainless steel weldments, for the successful ultrasonic examination. The test welds have been subjected to repeated welding cycles and the ultrasonic parameters including the defect characterization have been evaluated for analysis. The paper discusses the approach followed, analysis, results obtained and the recommendations based on the above. 1 fig., 2 tabs

  18. Time-lapse seismic - repeatability versus usefulness and 2D versus 3D

    Science.gov (United States)

    Landro, M.

    2017-12-01

    Time-lapse seismic has developed rapidly over the past decades, especially for monitoring of oil and gas reservoirs and subsurface storage of CO2. I will review and discuss some of the critical enabling factors for the commercial success of this technology. It was early realized that how well we are able to repeat our seismic experiment is crucial. However, it is always a question of detectability versus repeatability. For marine seismic, there are several factors limiting the repeatability: Weather conditions, positioning of sources and receivers and so on. I will discuss recent improvements in both acquisition and processing methods over the last decade. It is well known that repeated 3D seismic data is the most accurate tool for reservoir monitoring purposes. However, several examples show that 2D seismic data may be used for monitoring purposes despite lower repeatability. I will use examples from an underground blow out in the North Sea, and repeated 2D seismic lines acquired before and after the Tohoku earthquake in 2011 to illustrate this. A major challenge when using repeated 2D seismic for subsurface monitoring purposes is the lack of 3D calibration points and significantly less amount of data. For marine seismic acquisition, feathering issues and crossline dip effects become more critical compared to 3D seismic acquisition. Furthermore, the uncertainties arising from a non-ideal 2D seismic acquisition are hard to assess, since the 3D subsurface geometry has not been mapped. One way to shed more light on this challenge is to use 3D time lapse seismic modeling testing various crossline dips or geometries. Other ways are to use alternative data sources, such as bathymetry, time lapse gravity or electromagnetic data. The end result for all time-lapse monitoring projects is an interpretation associated with uncertainties, and for the 2D case these uncertainties are often large. The purpose of this talk is to discuss how to reduces and control these

  19. Repeated tender point injections of granisetron alleviate chronic myofascial pain--a randomized, controlled, double-blinded trial.

    Science.gov (United States)

    Christidis, Nikolaos; Omrani, Shahin; Fredriksson, Lars; Gjelset, Mattias; Louca, Sofia; Hedenberg-Magnusson, Britt; Ernberg, Malin

    2015-01-01

    Serotonin (5-HT) mediates pain by peripheral 5-HT3-receptors. Results from a few studies indicate that intramuscular injections of 5-HT3-antagonists may reduce musculoskeletal pain. The aim of this study was to investigate if repeated intramuscular tender-point injections of the 5-HT3-antagonist granisetron alleviate pain in patients with myofascial temporomandibular disorders (M-TMD). This prospective, randomized, controlled, double blind, parallel-arm trial (RCT) was carried out during at two centers in Stockholm, Sweden. The randomization was performed by a researcher who did not participate in data collection with an internet-based application ( www.randomization.com ). 40 patients with a diagnose of M-TMD according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) were randomized to receive repeated injections, one week apart, with either granisetron (GRA; 3 mg) or isotonic saline as control (CTR). The median weekly pain intensities decreased significantly at all follow-ups (1-, 2-, 6-months) in the GRA-group (Friedman test; P  0.075). The numbers needed to treat (NNT) were 4 at the 1- and 6-month follow-ups, and 3.3 at the 2-month follow-up in favor of granisetron. Repeated intramuscular tender-point injections with granisetron provide a new pharmacological treatment possibility for myofascial pain patients with repeated intramuscular tender-point injections with the serotonin type 3 antagonist granisetron. It showed a clinically relevant pain reducing effect in the temporomandibular region, both in a short- and long-term aspect. European Clinical Trials Database 2005-006042-41 as well as at Clinical Trials NCT02230371 .

  20. Effect of tramadol on metamizol pharmacokinetics and pharmacodynamics after single and repeated administrations in arthritic rats

    Directory of Open Access Journals (Sweden)

    Luis Alfonso Moreno-Rocha

    2016-11-01

    Full Text Available Combined administration of certain doses of opioid compounds with a non-steroidal anti-inflammatory drug can produce additive or supra-additive effects while reducing unwanted effects. We have recently reported that co-administration of metamizol with tramadol produces antinociceptive effect potentiation, after acute treatment. However, none information about the effect produced by the combination after chronic or repeated dose administration exists. The aims of this study were to investigate whether the antinociceptive synergism produced by the combination of metamizol and tramadol (177.8 + 17.8 mg/kg, s.c. respectively is maintained after repeated treatment and whether the effects observed are primarily due to pharmacodynamic interactions or may be related to pharmacokinetics changes. Administration of metamizol plus tramadol acute treatment significantly enhanced the antinociceptive effect of the drugs given alone (P  0.05. The mechanism involved in the synergism of the antinociceptive effect observed with the combination of metamizol and tramadol in single dose cannot be attributed to a pharmacokinetic interaction, and other pharmacodynamic interactions have to be considered. On the other hand, when metamizol and tramadol were co-administered under repeated administrations, a pharmacokinetic interaction and tolerance development occurred. Differences found in metamizol active metabolites’ pharmacokinetics (P < 0.05 were related to the development of tolerance produced by the combination after repeated doses. This work shows an additional preclinical support for the combination therapy. The clinical utility of this combination in a suitable dose range should be evaluated in future studies.

  1. Androgen receptor CAG repeats length polymorphism and the risk of polycystic ovarian syndrome (PCOS.

    Directory of Open Access Journals (Sweden)

    Singh Rajender

    Full Text Available OBJECTIVE: Polycystic ovarian syndrome (PCOS refers to an inheritable androgen excess disorder characterized by multiple small follicles located at the ovarian periphery. Hyperandrogenism in PCOS, and inverse correlation between androgen receptor (AR CAG numbers and AR function, led us to hypothesize that CAG length variations may affect PCOS risk. METHODS: CAG repeat region of 169 patients recruited following strictly defined Rotterdam (2003 inclusion criteria and that of 175 ethnically similar control samples, were analyzed. We also conducted a meta-analysis on the data taken from published studies, to generate a pooled estimate on 2194 cases and 2242 controls. RESULTS: CAG bi-allelic mean length was between 8.5 and 24.5 (mean = 17.43, SD = 2.43 repeats in the controls and between 11 and 24 (mean = 17.39, SD = 2.29 repeats in the cases, without any significant difference between the two groups. Further, comparison of bi-allelic mean and its frequency distribution in three categories (short, moderate and long alleles did not show any significant difference between controls and various case subgroups. Frequency distribution of bi-allelic mean in two categories (extreme and moderate alleles showed over-representation of extreme sized alleles in the cases with marginally significant value (50.3% vs. 61.5%, χ(2 = 4.41; P = 0.036, which turned insignificant upon applying Bonferroni correction for multiple comparisons. X-chromosome inactivation analysis showed no significant difference in the inactivation pattern of CAG alleles or in the comparison of weighed bi-allelic mean between cases and controls. Meta-analysis also showed no significant correlation between CAG length and PCOS risk, except a minor over-representation of short CAG alleles in the cases. CONCLUSION: CAG bi-allelic mean length did not differ between controls and cases/case sub-groups nor did the allele distribution. Over-representation of short

  2. Androgen receptor CAG repeats length polymorphism and the risk of polycystic ovarian syndrome (PCOS).

    Science.gov (United States)

    Rajender, Singh; Carlus, Silas Justin; Bansal, Sandeep Kumar; Negi, Mahendra Pal Singh; Negi, Mahendra Pratap Singh; Sadasivam, Nirmala; Sadasivam, Muthusamy Narayanan; Thangaraj, Kumarasamy

    2013-01-01

    Polycystic ovarian syndrome (PCOS) refers to an inheritable androgen excess disorder characterized by multiple small follicles located at the ovarian periphery. Hyperandrogenism in PCOS, and inverse correlation between androgen receptor (AR) CAG numbers and AR function, led us to hypothesize that CAG length variations may affect PCOS risk. CAG repeat region of 169 patients recruited following strictly defined Rotterdam (2003) inclusion criteria and that of 175 ethnically similar control samples, were analyzed. We also conducted a meta-analysis on the data taken from published studies, to generate a pooled estimate on 2194 cases and 2242 controls. CAG bi-allelic mean length was between 8.5 and 24.5 (mean = 17.43, SD = 2.43) repeats in the controls and between 11 and 24 (mean = 17.39, SD = 2.29) repeats in the cases, without any significant difference between the two groups. Further, comparison of bi-allelic mean and its frequency distribution in three categories (short, moderate and long alleles) did not show any significant difference between controls and various case subgroups. Frequency distribution of bi-allelic mean in two categories (extreme and moderate alleles) showed over-representation of extreme sized alleles in the cases with marginally significant value (50.3% vs. 61.5%, χ(2) = 4.41; P = 0.036), which turned insignificant upon applying Bonferroni correction for multiple comparisons. X-chromosome inactivation analysis showed no significant difference in the inactivation pattern of CAG alleles or in the comparison of weighed bi-allelic mean between cases and controls. Meta-analysis also showed no significant correlation between CAG length and PCOS risk, except a minor over-representation of short CAG alleles in the cases. CAG bi-allelic mean length did not differ between controls and cases/case sub-groups nor did the allele distribution. Over-representation of short/extreme-sized alleles in the cases may be a chance finding

  3. Germ-line CAG repeat instability causes extreme CAG repeat expansion with infantile-onset spinocerebellar ataxia type 2

    DEFF Research Database (Denmark)

    Vinther-Jensen, Tua; Ek, Jakob; Duno, Morten

    2013-01-01

    The spinocerebellar ataxias (SCA) are a genetically and clinically heterogeneous group of diseases, characterized by dominant inheritance, progressive cerebellar ataxia and diverse extracerebellar symptoms. A subgroup of the ataxias is caused by unstable CAG-repeat expansions in their respective ...... of paternal germ-line repeat sequence instability of the expanded SCA2 locus.European Journal of Human Genetics advance online publication, 10 October 2012; doi:10.1038/ejhg.2012.231....

  4. Spleen and thymic sonography as estimator of the immune response in children with repeated infections

    International Nuclear Information System (INIS)

    Rabaza, Jesus; Fundora, Hermes; Rodriguez, Alexis; Hernandez, Maria de los Angeles

    2010-01-01

    The spleen is a secondary lymphoid organ. The spleen has many functions: IgM class antibody production and phagocytosis of encapsulated bacteria. We propose to measure the dimensions of the spleen in children with repeated infections, in order to describe them as a diagnosis marker and to explore the probable correlation between the thymic characteristics and the dimensions of the spleen. We study 81 patients that attended the consultation of Immunology from Aballi hospital with repeated infections and they were from 8 months to 9 years old. Children with nutritional value up to the third percentile and those taking steroids 45 days before the study were excluded. We measured the thymic and splenic areas by mediastinal and abdominal echography. The length, the splenic index and the weight are less in patients with repeated infections. These data were significant in 12 to 23 month of age group. The length and the splenic index were less in patients with depletion of thymic area. The sonographic evaluation of the spleen is very important in patients from 1 to 2 years old and in patients with thymic depletion, because they are on the age of vaccine administration according to the Cuban schedule and having affected a main organ for immune response might be a reason for them to show a deficient response and need special schedules

  5. Multi Directional Repeated Sprint Is a Valid and Reliable Test for Assessment of Junior Handball Players

    Directory of Open Access Journals (Sweden)

    Amin Daneshfar

    2018-04-01

    Full Text Available The aim of the present study was to examine the validity and reliability of a 10 × (6 × 5 m multi-directional repeated sprint ability test (RSM in elite young team handball (TH players. Participants were members of the Iranian national team (n = 20, age 16.4 ± 0.7 years, weight 82.5 ± 5.5 kg, height 184.8 ± 4.6 cm, body fat 15.4 ± 4.3%. The validity of RSM was tested against a 10 × (15 + 15 m repeated sprint ability test (RSA, Yo-Yo Intermittent Recovery test Level 1 (Yo-Yo IR1, squat jump (SJ and countermovement jump (CMJ. To test the reliability of RSM, the participants repeated the testing sessions of RSM and RSA 1 week later. Both RSA and RSM tests showed good to excellent reliability of the total time (TT, best time (BT, and weakest time (WT. The results of the correlation analysis showed significant inverse correlations between maximum aerobic capacity and TT in RSA (r = −0.57, p ≤ 0.05 and RSM (r = −0.76, p ≤ 0.01. There was also a significant inverse correlation between maximum aerobic capacity with fatigue index (FI in RSA test (r = −0.64, p ≤ 0.01 and in RSM test (r = −0.53, p ≤ 0.05. BT, WT, and TT of RSA was largely-to-very largely correlated with BT (r = 0.58, p ≤ 0.01, WT (r = 0.62, p ≤ 0.01, and TT (r = 0.65, p ≤ 0.01 of RSM. BT in RSM was also correlated with FI in RSM (r = 0.88, p ≤ 0.01. In conclusion, based on the findings of the current study, the recently developed RSM test is a valid and reliable test and should be utilized for assessment of repeated sprint ability in handball players.

  6. Multi Directional Repeated Sprint Is a Valid and Reliable Test for Assessment of Junior Handball Players

    Science.gov (United States)

    Daneshfar, Amin; Gahreman, Daniel E.; Koozehchian, Majid S.; Amani Shalamzari, Sadegh; Hassanzadeh Sablouei, Mozhgan; Rosemann, Thomas; Knechtle, Beat; Nikolaidis, Pantelis T.

    2018-01-01

    The aim of the present study was to examine the validity and reliability of a 10 × (6 × 5 m) multi-directional repeated sprint ability test (RSM) in elite young team handball (TH) players. Participants were members of the Iranian national team (n = 20, age 16.4 ± 0.7 years, weight 82.5 ± 5.5 kg, height 184.8 ± 4.6 cm, body fat 15.4 ± 4.3%). The validity of RSM was tested against a 10 × (15 + 15 m) repeated sprint ability test (RSA), Yo-Yo Intermittent Recovery test Level 1 (Yo-Yo IR1), squat jump (SJ) and countermovement jump (CMJ). To test the reliability of RSM, the participants repeated the testing sessions of RSM and RSA 1 week later. Both RSA and RSM tests showed good to excellent reliability of the total time (TT), best time (BT), and weakest time (WT). The results of the correlation analysis showed significant inverse correlations between maximum aerobic capacity and TT in RSA (r = −0.57, p ≤ 0.05) and RSM (r = −0.76, p ≤ 0.01). There was also a significant inverse correlation between maximum aerobic capacity with fatigue index (FI) in RSA test (r = −0.64, p ≤ 0.01) and in RSM test (r = −0.53, p ≤ 0.05). BT, WT, and TT of RSA was largely-to-very largely correlated with BT (r = 0.58, p ≤ 0.01), WT (r = 0.62, p ≤ 0.01), and TT (r = 0.65, p ≤ 0.01) of RSM. BT in RSM was also correlated with FI in RSM (r = 0.88, p ≤ 0.01). In conclusion, based on the findings of the current study, the recently developed RSM test is a valid and reliable test and should be utilized for assessment of repeated sprint ability in handball players. PMID:29670536

  7. Effects of rearing environment and population origin on responses to repeated behavioural trials in cane toads (Rhinella marina).

    Science.gov (United States)

    Gruber, Jodie; Whiting, Martin J; Brown, Gregory; Shine, Richard

    2018-05-02

    Behavioural response to repeated trials in captivity can be driven by many factors including rearing environment, population of origin, habituation to captivity/trial conditions and an individual's behavioural type (e.g., bold versus shy). We tested the effect of rearing environment (captive raised common-garden versus wild-caught) and population origin (range-edge versus range-front) on the responses of invasive cane toads (Rhinella marina) to repeated exploration and risk-taking assays in captivity. We found that behavioural responses to identical assays performed on two occasions were complex and showed few consistent patterns based on rearing environment or population of origin. However, behavioural traits were repeatable across Trial Blocks when all sample populations were grouped together, indicating general consistency in individual toad behaviour across repeated behavioural assays. Our findings exemplify the complexity and unpredictability of behavioural responses and their effects on the repeatability and interpretation of behavioural traits across repeated behavioural assays in captivity. To meaningfully interpret the results from repeated behavioural assays, we need to consider how multiple factors may affect behavioural responses to these tests and importantly, how these responses may affect the repeatability of behavioural traits across time. Copyright © 2018. Published by Elsevier B.V.

  8. Changes in the state of heat-resistant steel induced by repeated hot deformation

    Science.gov (United States)

    Lyubimova, Lyudmila L.; Fisenko, Roman N.; Tashlykov, Alexander A.; Tabakaev, Roman B.

    2018-01-01

    This work deals with the problems of structural regeneration by thermal restoration treatment (TRT). These include the lack of a structural sign showing that TRT is possible, a consensus on TRT modes, the data on the necessary relaxation depth of residual stresses, or criteria of structural restoration. Performing a TRT without solving these problems may deteriorate the properties of steel or even accelerate its destruction. With this in view, the purpose of this work is to determine experimentally how the residual stress state changes under thermal and mechanical loads in order to specify the signs of the restoration of structure and structural stability. The object of this research is unused 12Cr1MoV steel that has been aged naturally for 13 years. Using X-ray dosimetry with X-ray spectral analysis, we study the distribution of internal residual stresses of the first kind during the repeated hot deformation. After repeated thermal deformation, the sample under study transforms from a viscoelastic Maxwell material into a Kelvin-Voigt material, which facilitates structural stabilization. A sign of this is the relaxation limit increase, prevention of continuous decay of an α-solid solution of iron and restoration of the lattice parameter.

  9. Measurement of repeat effects in Chicago’s criminal social network

    Directory of Open Access Journals (Sweden)

    Paul Kump

    2016-07-01

    Full Text Available The “near-repeat” effect is a well-known criminological phenomenon in which the occurrence of a crime incident gives rise to a temporary elevation of crime risk within close physical proximity to an initial incident. Adopting a social network perspective, we instead define a near repeat in terms of geodesic distance within a criminal social network, rather than spatial distance. Specifically, we report a statistical analysis of repeat effects in arrest data for Chicago during the years 2003–2012. We divide the arrest data into two sets (violent crimes and other crimes and, for each set, we compare the distributions of time intervals between repeat incidents to theoretical distributions in which repeat incidents occur only by chance. We first consider the case of the same arrestee participating in repeat incidents (“exact repeats” and then extend the analysis to evaluate repeat risks of those arrestees near one another in the social network. We observe repeat effects that diminish as a function of geodesic distance and time interval, and we estimate typical time scales for repeat crimes in Chicago.

  10. The effect of stimulation interval on plasticity following repeated blocks of intermittent theta burst stimulation.

    Science.gov (United States)

    Tse, Nga Yan; Goldsworthy, Mitchell R; Ridding, Michael C; Coxon, James P; Fitzgerald, Paul B; Fornito, Alex; Rogasch, Nigel C

    2018-06-04

    This study assessed the effect of interval duration on the direction and magnitude of changes in cortical excitability and inhibition when applying repeated blocks of intermittent theta burst stimulation (iTBS) over motor cortex. 15 participants received three different iTBS conditions on separate days: single iTBS; repeated iTBS with a 5 minute interval (iTBS-5-iTBS); and with a 15 minute interval (iTBS-15-iTBS). Changes in cortical excitability and short-interval cortical inhibition (SICI) were assessed via motor-evoked potentials (MEPs) before and up to 60 mins following stimulation. iTBS-15-iTBS increased MEP amplitude for up to 60 mins post stimulation, whereas iTBS-5-iTBS decreased MEP amplitude. In contrast, MEP amplitude was not altered by single iTBS. Despite the group level findings, only 53% of individuals showed facilitated MEPs following iTBS-15-iTBS, and only 40% inhibited MEPs following iTBS-5-iTBS. Modulation of SICI did not differ between conditions. These results suggest interval duration between spaced iTBS plays an important role in determining the direction of plasticity on excitatory, but not inhibitory circuits in human motor cortex. While repeated iTBS can increase the magnitude of MEP facilitation/inhibition in some individuals compared to single iTBS, the response to repeated iTBS appears variable between individuals in this small sample.

  11. Identification of Pentatricopeptide Repeat Proteins in the Model Organism Dictyostelium discoideum

    Directory of Open Access Journals (Sweden)

    Sam Manna

    2013-01-01

    Full Text Available Pentatricopeptide repeat (PPR proteins are RNA binding proteins with functions in organelle RNA metabolism. They are found in all eukaryotes but have been most extensively studied in plants. We report on the identification of 12 PPR-encoding genes in the genome of the protist Dictyostelium discoideum, with potential homologs in other members of the same lineage and some predicted novel functions for the encoded gene products in protists. For one of the gene products, we show that it localizes to the mitochondria, and we also demonstrate that antisense inhibition of its expression leads to slower growth, a phenotype associated with mitochondrial dysfunction.

  12. Repeated Microneedle Stimulation Induces Enhanced Hair Growth in a Murine Model.

    Science.gov (United States)

    Kim, Yoon Seob; Jeong, Kwan Ho; Kim, Jung Eun; Woo, Young Jun; Kim, Beom Joon; Kang, Hoon

    2016-10-01

    Microneedle is a method that creates transdermal microchannels across the stratum corneum barrier layer of skin. No previous study showed a therapeutic effect of microneedle itself on hair growth by wounding. The aim of this study is to investigate the effect of repeated microwound formed by microneedle on hair growth and hair growth-related genes in a murine model. A disk microneedle roller was applied to each group of mice five times a week for three weeks. First, to identify the optimal length and cycle, microneedles of lengths of 0.15 mm, 0.25 mm, 0.5 mm, and 1 mm and cycles of 3, 6, 10, and 13 cycles were applied. Second, the effect of hair growth and hair-growth-related genes such as Wnt3a, β-catenin, vascular endothelial growth factor (VEGF), and Wnt10b was observed using optimized microneedle. Outcomes were observed using visual inspection, real-time polymerase chain reaction, and immunohistochemistry. We found that the optimal length and cycle of microneedle treatment on hair growth was 0.25 mm/10 cycles and 0.5 mm/10 cycles. Repeated microneedle stimulation promoted hair growth, and it also induced the enhanced expression of Wnt3a, β-catenin, VEGF, and Wnt10b. Our study provides evidence that microneedle stimulation can induce hair growth via activation of the Wnt/β-catenin pathway and VEGF. Combined with the drug delivery effect, we believe that microneedle stimulation could lead to new approaches for alopecia.

  13. Prospective study on determinants of repeat attendance and attendance patterns in breast cancer screening using the Theory of Planned Behaviour.

    NARCIS (Netherlands)

    Drossaert, Constance H.C.; Boer, Hendrik; Seydel, E.R.

    2003-01-01

    This prospective study, using the Theory of Planned Behaviour (TPB) as a theoretical framework, was carried out to identify the determinants of repeat attendance and attendance patterns in organised breast screening. A group of 2657 women filled out a baseline questionnaire, approximately 8 weeks

  14. Effect of repeated contact on adhesion measurements involving polydimethylsiloxane structural material

    International Nuclear Information System (INIS)

    Kroner, E; Arzt, E; Maboudian, R

    2009-01-01

    During the last few years several research groups have focused on the fabrication of artificial gecko inspired adhesives. For mimicking these structures, different polymers are used as structure material, such as polydimethylsiloxanes (PDMS), polyurethanes (PU), and polypropylene (PP). While these polymers can be structured easily and used for artificial adhesion systems, the effects of repeated adhesion testing have never been investigated closely. In this paper we report on the effect of repeated adhesion measurements on the commercially available poly(dimethylsiloxane) polymer kit Sylgard 184 (Dow Corning). We show that the adhesion force decreases as a function of contact cycles. The rate of change and the final value of adhesion are found to depend on the details of the PDMS synthesis and structuring.

  15. Repeat prenatal corticosteroid prior to preterm birth: a systematic review and individual participant data meta-analysis for the PRECISE study group (prenatal repeat corticosteroid international IPD study group: assessing the effects using the best level of evidence - study protocol

    Directory of Open Access Journals (Sweden)

    Crowther Caroline A

    2012-02-01

    Full Text Available Abstract Background The aim of this individual participant data (IPD meta-analysis is to assess whether the effects of repeat prenatal corticosteroid treatment given to women at risk of preterm birth to benefit their babies are modified in a clinically meaningful way by factors related to the women or the trial protocol. Methods/Design The Prenatal Repeat Corticosteroid International IPD Study Group: assessing the effects using the best level of Evidence (PRECISE Group will conduct an IPD meta-analysis. The PRECISE International Collaborative Group was formed in 2010 and data collection commenced in 2011. Eleven trials with up to 5,000 women and 6,000 infants are eligible for the PRECISE IPD meta-analysis. The primary study outcomes for the infants will be serious neonatal outcome (defined by the PRECISE International IPD Study Group as one of death (foetal, neonatal or infant; severe respiratory disease; severe intraventricular haemorrhage (grade 3 and 4; chronic lung disease; necrotising enterocolitis; serious retinopathy of prematurity; and cystic periventricular leukomalacia; use of respiratory support (defined as mechanical ventilation or continuous positive airways pressure or other respiratory support; and birth weight (Z-scores. For the children, the primary study outcomes will be death or any neurological disability (however defined by trialists at childhood follow up and may include developmental delay or intellectual impairment (developmental quotient or intelligence quotient more than one standard deviation below the mean, cerebral palsy (abnormality of tone with motor dysfunction, blindness (for example, corrected visual acuity worse than 6/60 in the better eye or deafness (for example, hearing loss requiring amplification or worse. For the women, the primary outcome will be maternal sepsis (defined as chorioamnionitis; pyrexia after trial entry requiring the use of antibiotics; puerperal sepsis; intrapartum fever requiring the use

  16. Modeling and evaluating repeatability and reproducibility of ordinal classifications

    NARCIS (Netherlands)

    de Mast, J.; van Wieringen, W.N.

    2010-01-01

    This paper argues that currently available methods for the assessment of the repeatability and reproducibility of ordinal classifications are not satisfactory. The paper aims to study whether we can modify a class of models from Item Response Theory, well established for the study of the reliability

  17. Contraceptive Use among Women Seeking Repeat Abortion in ...

    African Journals Online (AJOL)

    AJRH Managing Editor

    Compared with women seeking their first abortion, significantly more repeat abortion clients had ever used contraceptives ... findings, the level of repeat abortions in Europe, .... and contraceptive history, and post-abortion ..... working women.

  18. CUSTOMER LOYALTY IN THE SMALL MEDIUM SIZED RETAIL JEWELLERY FIRMS WHAT EXTENT DOES LOYALTY SCHEMES HAVE AN IMPACT ON REPEAT PATRONAGE? WHAT OTHER FACTORS CAUSE REPEAT PATRONAGE?: A DYADIC EXPLORATION

    OpenAIRE

    DALAL, AVANI

    2006-01-01

    ABSTRACT This study looks at the post-purchase evaluation stage of consumers and what causes loyalty. The industry under investigation is Small Medium Sized Jewellery Retailers. The purpose of this study is to develop a deeper understanding of how customer loyalty is developed. To reach this aim the study focuses on the impact of loyalty schemes on repeat patronage. This paper aims to contribute to the existing literature on repeat patronage and factors that lead to customer loyalty. A wi...

  19. (In)Consistencies in Responses to Sodium Bicarbonate Supplementation: A Randomised, Repeated Measures, Counterbalanced and Double-Blind Study.

    Science.gov (United States)

    Froio de Araujo Dias, Gabriela; da Eira Silva, Vinicius; de Salles Painelli, Vitor; Sale, Craig; Giannini Artioli, Guilherme; Gualano, Bruno; Saunders, Bryan

    2015-01-01

    Intervention studies do not account for high within-individual variation potentially compromising the magnitude of an effect. Repeat administration of a treatment allows quantification of individual responses and determination of the consistency of responses. We determined the consistency of metabolic and exercise responses following repeated administration of sodium bicarbonate (SB). 15 physically active males (age 25±4 y; body mass 76.0±7.3 kg; height 1.77±0.05 m) completed six cycling capacity tests at 110% of maximum power output (CCT110%) following ingestion of either 0.3 g∙kg-1BM of SB (4 trials) or placebo (PL, 2 trials). Blood pH, bicarbonate, base excess and lactate were determined at baseline, pre-exercise, post-exercise and 5-min post-exercise. Total work done (TWD) was recorded as the exercise outcome. SB supplementation increased blood pH, bicarbonate and base excess prior to every trial (all p ≤ 0.001); absolute changes in pH, bicarbonate and base excess from baseline to pre-exercise were similar in all SB trials (all p > 0.05). Blood lactate was elevated following exercise in all trials (p ≤ 0.001), and was higher in some, but not all, SB trials compared to PL. TWD was not significantly improved with SB vs. PL in any trial (SB1: +3.6%; SB2 +0.3%; SB3: +2.1%; SB4: +6.7%; all p > 0.05), although magnitude-based inferences suggested a 93% likely improvement in SB4. Individual analysis showed ten participants improved in at least one SB trial above the normal variation of the test although five improved in none. The mechanism for improved exercise with SB was consistently in place prior to exercise, although this only resulted in a likely improvement in one trial. SB does not consistently improve high intensity cycling capacity, with results suggesting that caution should be taken when interpreting the results from single trials as to the efficacy of SB supplementation. ClinicalTrials.gov NCT02474628.

  20. (InConsistencies in Responses to Sodium Bicarbonate Supplementation: A Randomised, Repeated Measures, Counterbalanced and Double-Blind Study.

    Directory of Open Access Journals (Sweden)

    Gabriela Froio de Araujo Dias

    Full Text Available Intervention studies do not account for high within-individual variation potentially compromising the magnitude of an effect. Repeat administration of a treatment allows quantification of individual responses and determination of the consistency of responses. We determined the consistency of metabolic and exercise responses following repeated administration of sodium bicarbonate (SB.15 physically active males (age 25±4 y; body mass 76.0±7.3 kg; height 1.77±0.05 m completed six cycling capacity tests at 110% of maximum power output (CCT110% following ingestion of either 0.3 g∙kg-1BM of SB (4 trials or placebo (PL, 2 trials. Blood pH, bicarbonate, base excess and lactate were determined at baseline, pre-exercise, post-exercise and 5-min post-exercise. Total work done (TWD was recorded as the exercise outcome.SB supplementation increased blood pH, bicarbonate and base excess prior to every trial (all p ≤ 0.001; absolute changes in pH, bicarbonate and base excess from baseline to pre-exercise were similar in all SB trials (all p > 0.05. Blood lactate was elevated following exercise in all trials (p ≤ 0.001, and was higher in some, but not all, SB trials compared to PL. TWD was not significantly improved with SB vs. PL in any trial (SB1: +3.6%; SB2 +0.3%; SB3: +2.1%; SB4: +6.7%; all p > 0.05, although magnitude-based inferences suggested a 93% likely improvement in SB4. Individual analysis showed ten participants improved in at least one SB trial above the normal variation of the test although five improved in none.The mechanism for improved exercise with SB was consistently in place prior to exercise, although this only resulted in a likely improvement in one trial. SB does not consistently improve high intensity cycling capacity, with results suggesting that caution should be taken when interpreting the results from single trials as to the efficacy of SB supplementation.ClinicalTrials.gov NCT02474628.

  1. Repeat Gamma Knife Radiosurgery for Trigeminal Neuralgia

    International Nuclear Information System (INIS)

    Aubuchon, Adam C.; Chan, Michael D.; Lovato, James F.; Balamucki, Christopher J.; Ellis, Thomas L.; Tatter, Stephen B.; McMullen, Kevin P.; Munley, Michael T.; Deguzman, Allan F.; Ekstrand, Kenneth E.; Bourland, J. Daniel; Shaw, Edward G.

    2011-01-01

    Purpose: Repeat gamma knife stereotactic radiosurgery (GKRS) for recurrent or persistent trigeminal neuralgia induces an additional response but at the expense of an increased incidence of facial numbness. The present series summarized the results of a repeat treatment series at Wake Forest University Baptist Medical Center, including a multivariate analysis of the data to identify the prognostic factors for treatment success and toxicity. Methods and Materials: Between January 1999 and December 2007, 37 patients underwent a second GKRS application because of treatment failure after a first GKRS treatment. The mean initial dose in the series was 87.3 Gy (range, 80–90). The mean retreatment dose was 84.4 Gy (range, 60–90). The dosimetric variables recorded included the dorsal root entry zone dose, pons surface dose, and dose to the distal nerve. Results: Of the 37 patients, 81% achieved a >50% pain relief response to repeat GKRS, and 57% experienced some form of trigeminal dysfunction after repeat GKRS. Two patients (5%) experienced clinically significant toxicity: one with bothersome numbness and one with corneal dryness requiring tarsorraphy. A dorsal root entry zone dose at repeat treatment of >26.6 Gy predicted for treatment success (61% vs. 32%, p = .0716). A cumulative dorsal root entry zone dose of >84.3 Gy (72% vs. 44%, p = .091) and a cumulative pons surface dose of >108.5 Gy (78% vs. 44%, p = .018) predicted for post-GKRS numbness. The presence of any post-GKRS numbness predicted for a >50% decrease in pain intensity (100% vs. 60%, p = .0015). Conclusion: Repeat GKRS is a viable treatment option for recurrent trigeminal neuralgia, although the patient assumes a greater risk of nerve dysfunction to achieve maximal pain relief.

  2. Repeat Gamma Knife Radiosurgery for Trigeminal Neuralgia

    Energy Technology Data Exchange (ETDEWEB)

    Aubuchon, Adam C., E-mail: acaubuchon@gmail.com [Department of Radiation Oncology, Wake Forest University School of Medicine, Winston-Salem, NC (United States); Chan, Michael D. [Department of Radiation Oncology, Wake Forest University School of Medicine, Winston-Salem, NC (United States); Lovato, James F. [Department of Public Health Sciences, Wake Forest University School of Medicine, Winston-Salem, NC (United States); Balamucki, Christopher J. [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States); Ellis, Thomas L.; Tatter, Stephen B. [Department of Neurosurgery, Wake Forest University School of Medicine, Winston-Salem, NC (United States); McMullen, Kevin P.; Munley, Michael T.; Deguzman, Allan F.; Ekstrand, Kenneth E.; Bourland, J. Daniel; Shaw, Edward G. [Department of Radiation Oncology, Wake Forest University School of Medicine, Winston-Salem, NC (United States)

    2011-11-15

    Purpose: Repeat gamma knife stereotactic radiosurgery (GKRS) for recurrent or persistent trigeminal neuralgia induces an additional response but at the expense of an increased incidence of facial numbness. The present series summarized the results of a repeat treatment series at Wake Forest University Baptist Medical Center, including a multivariate analysis of the data to identify the prognostic factors for treatment success and toxicity. Methods and Materials: Between January 1999 and December 2007, 37 patients underwent a second GKRS application because of treatment failure after a first GKRS treatment. The mean initial dose in the series was 87.3 Gy (range, 80-90). The mean retreatment dose was 84.4 Gy (range, 60-90). The dosimetric variables recorded included the dorsal root entry zone dose, pons surface dose, and dose to the distal nerve. Results: Of the 37 patients, 81% achieved a >50% pain relief response to repeat GKRS, and 57% experienced some form of trigeminal dysfunction after repeat GKRS. Two patients (5%) experienced clinically significant toxicity: one with bothersome numbness and one with corneal dryness requiring tarsorraphy. A dorsal root entry zone dose at repeat treatment of >26.6 Gy predicted for treatment success (61% vs. 32%, p = .0716). A cumulative dorsal root entry zone dose of >84.3 Gy (72% vs. 44%, p = .091) and a cumulative pons surface dose of >108.5 Gy (78% vs. 44%, p = .018) predicted for post-GKRS numbness. The presence of any post-GKRS numbness predicted for a >50% decrease in pain intensity (100% vs. 60%, p = .0015). Conclusion: Repeat GKRS is a viable treatment option for recurrent trigeminal neuralgia, although the patient assumes a greater risk of nerve dysfunction to achieve maximal pain relief.

  3. Do repeated rumble strip hits improve driver alertness?

    NARCIS (Netherlands)

    Watling, C.N.; Akerstedt, T.; Kecklund, L.G.; Anund, A.

    2016-01-01

    Driving while sleepy is associated with increased crash risk. Rumble strips are designed to alert a sleepy or inattentive driver when they deviate outside their driving lane. The current study sought to examine the effects of repeated rumble strip hits on levels of physiological and subjective

  4. X-Chromosome short tandem repeat, advantages and typing ...

    African Journals Online (AJOL)

    Microsatellites of the X-chromosome have been increasingly studied in recent years as a useful tool in forensic analysis. This review describes some details of X-chromosomal short tandem repeat (STR) analysis. Among them are: microsatellites, amplification using polymerase chain reaction (PCR) of STRs, PCR product ...

  5. Repeatability and correlations of dynamic contrast enhanced and T2* MRI in patients with advanced pancreatic ductal adenocarcinoma.

    Science.gov (United States)

    Klaassen, Remy; Gurney-Champion, Oliver J; Wilmink, Johanna W; Besselink, Marc G; Engelbrecht, Marc R W; Stoker, Jaap; Nederveen, Aart J; van Laarhoven, Hanneke W M

    2018-07-01

    In current oncological practice of pancreatic ductal adenocarcinoma (PDAC), there is a great demand for response predictors and markers for early treatment evaluation. In this study, we investigated the repeatability and the interaction of dynamic contrast enhanced (DCE) and T2* MRI in patients with advanced PDAC to enable for such evaluation using these techniques. 15 PDAC patients underwent two DCE, T2* and anatomical 3 T MRI sessions before start of treatment. Parametric maps were calculated for the transfer constant (K trans ), rate constant (k ep ), extracellular extravascular space (v e ) and perfusion fraction (v p ). Quantitative R2* (1/T2*) maps were obtained from the multi-echo T2* images. Differences between normal and cancerous pancreas were determined using a Wilcoxon matched pairs test. Repeatability was obtained using Bland-Altman analysis and relations between DCE and T2*/R2* were observed by Spearman correlation and voxel-wise binned plots of tumor voxels. PDAC K trans (p = 0.007), k ep (p T2*. Voxel wise analysis showed a steep increase in R2* for tumor voxels with lower K trans and v e . We showed good repeatability of DCE and T2* related MRI parameters in advanced PDAC patients. Furthermore, we have illustrated the relation of DCE K trans and v e with tissue T2* and R2* indicating substantial value of these parameters for detecting tumor hypoxia in future studies. The results from our study pave the way for further response evaluation studies and patient selection based on DCE and T2* parameters. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Repeated transsphenoidal surgery or gamma knife radiosurgery in recurrent cushing disease after transsphenoidal surgery.

    Science.gov (United States)

    Bodaghabadi, Mohammad; Riazi, Hooman; Aran, Shima; Bitaraf, Mohammad Ali; Alikhani, Mazdak; Alahverdi, Mahmud; Mohamadi, Masoumeh; Shalileh, Keivan; Azar, Maziar

    2014-03-01

    This study compared Gamma knife radiosurgery (GKRS) and repeated transsphenoidal adenomectomy (TSA) to find the best approach for recurrence of Cushing disease (CD) after unsuccessful first TSA. Fifty-two patients with relapse of CD after TSA were enrolled and randomly underwent a second surgery or GKRS as the next therapeutic approach. They were followed for a mean period of 3.05 ± 0.8 years by physical examination and hormone measurement as well as magnetic resonance imaging. No significant difference was observed in sex ratio, mean age, adenoma type, follow-up duration, and initial hormone level between the two groups. No significant relationship was found between preoperative 24-hour free urine cortisol and disease-free months or tumor volume among both groups. Our statistical analysis showed higher recurrence-free interval in the GKRS group compared with TSA group. With longer recurrence-free interval, GKRS could be considered a good treatment alternative to repeated TSA in recurrent CD. Georg Thieme Verlag KG Stuttgart · New York.

  7. Impact of short‐term, repeated water fasting on the weight of mice

    OpenAIRE

    Zahra Mishmast; Reza Rahimzadeh Oskuee; Amirali Aryan; Kamran Ghafarzadegan; Kiarash Ghazvini

    2014-01-01

    Introduction: Caloric restriction is a strategy applied for weight loss. Water fasting is a popular way for obesity treatment. However, little is known about the impact of water fasting on weight. Therefore, this study was conducted to investigate the effect of short-term, repeated water fasting on the weight of mice. Methods: In this study, the physiological effect of short-term, repeated water fasting on the weight of female mice was evaluated. At 6 weeks of age, mice were randomly assigned...

  8. WE-H-207A-04: Impact of Lesion Location On the Repeatability of 18F-NaF PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Lin, C; Perk, T; Harmon, S; Perlman, S; Liu, G; Jeraj, R [University of Wisconsin, Madison, WI (United States)

    2016-06-15

    Purpose: Quantifying the repeatability of imaging biomarkers is critical for assessing therapeutic response. While {sup 18}F-NaF PET/CT has shown to be a repeatable imaging method, research has not shown which factors may influence its repeatability. The purpose of this study was to evaluate whether the location of the lesion impacts the repeatability of quantitative {sup 18}F-NaF PET-derived SUV metrics. Methods: Metastatic castrate-resistant prostate cancer patients with multiple bone lesions received whole-body test-retest NaF PET/CT scans. Malignant bone lesions of PET-defined volume greater than 1.5 cm{sup 3} were identified by a nuclear medicine physician and automatically delineated using a SUV>15 threshold. The maximum (SUVmax), average (SUVmean), and total (SUVtotal) SUV were extracted from each lesion. Atlas-based segmentation was used to divide each patient skeleton into 25 skeletal regions. Test-retest repeatability of each SUV metric was assessed with coefficient of variation (CV). Results: A total of 265 malignant bone lesions from 18 patients were identified by nuclear medicine physician. The largest proportion of bone lesions were localized to the spine (41%), with 41% of those lesions localized to the thoracic spine. One-way ANOVA showed that measurement differences differed significantly for all three metrics across locations (p<0.01 for each metrics). Overall, CV was smallest for SUVmean at 5.3%, followed by SUVmax at 11.5% and SUVtotal at 20.4%. Lesions in the pubis were consistently the most repeatable (CV(SUVmax)= 5.6%, CV(SUVmean)= 0.6%, CV(SUVtotal)= 2.9%). According to SUVmean, repeatability was poorest in the cervical spine (CV = 6.2%), whereas according to SUVmax and SUVtotal, repeatability was poorest in the ribs (CV(SUVmax)= 15.0%, CV(SUVtotal)= 29.8%). Conclusion: Location of the lesion affects the repeatability of {sup 18}F-NaF PET/CT, with the ribs and cervical spine having the lowest repeatability and the pubis having the highest

  9. The effect of emotional design and online customer review on customer repeat purchase intention in online stores

    Science.gov (United States)

    Dewi, D. S.; Sudiarno, A.; Saputra, H.; Dewi, R. S.

    2018-04-01

    The internet users in Indonesia has increased rapidly over the last decade. A survey conducted by Association of Internet Service Providers Indonesia shows that the internet users has reached 34.9% of total population in Indonesia. The increase of internet users has led to a shift in trading practice from conventional trade to online trade. It is predicted in the next years the number of online consumers in Indonesia will continue to increase, provide many opportunity for online business. The huge number of internet users is not necesarily followed by the high number of e-purchase. It is therefore become the interest of many researchers to investigate factors that influence the decision on online purchasing.This research proposes a model that assess the effect of emotional design and customer review to customer intention on e-repeat purchase. Online questionnaire is designed and is distributed randomly through google forms. There are 187 respondent filled the questionnaire from which only 162 respondents actually have experience in online purchase. These data are then processed by using statistical analysis. A model is developed by applying structural equation modeling (SEM) approach. This study revealed that customer reviews especially objective reviews has a significant effect toward repeat purchase. Whereas emotional design particularly visual attractiveness also shows a significant effect toward e-repeat purchase.

  10. A Dual Repeat Cis-Element Determines Expression of GERANYL DIPHOSPHATE SYNTHASE for Monoterpene Production in Phalaenopsis Orchids

    Directory of Open Access Journals (Sweden)

    Yu-Chen Chuang

    2018-06-01

    Full Text Available Phalaenopsis bellina is a scented orchid emitting large amount of monoterpenes. GERANYL DIPHOSPHATE SYNTHASE (PbGDPS is the key enzyme for monoterpene biosynthesis, and shows concomitant expression with the emission of monoterpenes during flower development in P. bellina. Here, we identified a dual repeat cis-element in the GDPS promoter that is critical for monoterpene biosynthesis in Phalaenopsis orchids. A strong correlation between the dual repeat and the monoterpene production was revealed by examination of the GDPS promoter fragments over 12 Phalaenopsis species. Serial-deletion of the 2-kb GDPS promoter fragments demonstrated that the integrity of the dual repeat was crucial for its promoter activities. By screening the Arabidopsis transcription factors (TFs cDNA library using yeast one-hybrid assay, AtbZIP18, a member of group I of bZIP TFs, was identified to be able to bind the dual repeat. We then identified PbbZIP4 in the transcriptome of P. bellina, showing 83% identity in the DNA binding region with that of AtbZIP18, and the expression level of PbbZIP4 was higher in the scented orchids. In addition, PbbZIP4 transactivated the GDPS promoter fragment containing the dual repeat in dual luciferase assay. Furthermore, transient ectopic expression of PbbZIP4 induced a 10-fold production of monoterpenoids in the scentless orchid. In conclusion, these results indicate that the dual repeat is a real TF-bound cis-element significant for GDPS gene expression, and thus subsequent monoterpene biosynthesis in the scented Phalaenopsis orchids.

  11. Repeat HIV Testing at Voluntary Testing and Counseling Centers in Croatia: Successful HIV Prevention or Failure to Modify Risk Behaviors?

    Science.gov (United States)

    Matković Puljić, Vlatka; Kosanović Ličina, Mirjana Lana; Kavić, Marija; Nemeth Blažić, Tatjana

    2014-01-01

    HIV testing plays a critical role in preventing the spread of the virus and identifying infected individuals in need of care. Voluntary counseling and testing centers (VCTs) not only conduct testing but they also provide counseling. Since a proportion of people who test negative for HIV on their previous visit will return for retesting, the frequency of retesting and the characteristics of those who retest may provide insights into the efficacy of testing and counseling strategies. In this cross-sectional, retrospective study of 1,482 VCT clients in Croatia in 2010, 44.3% had been tested for HIV before. The rate of repeat HIV testing is lower in Croatia than in other countries. Men who have sex with men (MSM) clients, those with three or more sexual partners in the last 12 months, consistent condom users with steady partners, and intravenous drug users were more likely to be repeat testers. This finding suggests that clients presenting for repeat HIV testing are those who self-identify as being at a higher risk of infection. Our data showed that testing positive for HIV was not associated with repeat testing. However, the effects of repeat testing on HIV epidemiology needs to be explored. PMID:24705595

  12. PHYSIOLOGICAL RESPONSES AND MOOD STATES AFTER DAILY REPEATED PROLONGED EXERCISE

    Directory of Open Access Journals (Sweden)

    Ilkka Väänänen

    2004-10-01

    Full Text Available The purpose of this study was to describe the physiological responses to daily repeated acute but non-competitive prolonged exercise during a 4-day march and a 2-day cross-country ski event to the cardiorespiratory, autonomic nervous, musculoskeletal and endocrine systems. Mood states were also evaluated after these repeated exercises. The data of these short-term follow-up (reversal field trials was collected from healthy, 23 to 48 year old Finnish male soldiers in 1993 (n=6 and 1994 (n=15 during the "International Four-Day Long-Distance March" in Nijmegen, The Netherlands, and from ten healthy, 22 to 48 year old Finnish male participants in 1995 during a 2-day Finlandia Ski Race in Lahti, Finland. Acute cardiovascular responses were estimated by measuring the heart rate during exercise. The responses of the autonomic nervous system were estimated by measuring the heart rates during the orthostatic test. The musculoskeletal responses were estimated by measuring the perceived pains, flexibility, functional strength, use of elastic energy and oedemic changes of the lower extremities. Hormonal responses were estimated from the urinary excretion of catecholamines, and the concentrations of serum cortisol, testosterone, luteinizing (LH and follicle stimulating hormone (FSH. Mood states were assessed with the Profile of Mood States (POMS questionnaire. Daily walking time was 7-10 hours while the skiing time was 3 hours. Average heart rate during walking was 59% and skiing 87% of maximum heart rate. Morning heart rate in the supine position increased progressively through the marching period but not through the skiing experiment. After the first day, perceived pain increased significantly and remained at a similarly increased level until the end of the exercise period. Leg measurements showed no signs of oedema, decreases in flexibility, or functional strength. Catecholamine excretion rates during marches indicated cumulatively increased

  13. Evaluation of repeated dose micronucleus assays of the liver and gastrointestinal tract using potassium bromate: a report of the collaborative study by CSGMT/JEMS.MMS.

    Science.gov (United States)

    Okada, Emiko; Fujiishi, Yohei; Narumi, Kazunori; Kado, Shoichi; Wako, Yumi; Kawasako, Kazufumi; Kaneko, Kimiyuki; Ohyama, Wakako

    2015-03-01

    The food additive potassium bromate (KBrO3) is known as a renal carcinogen and causes chromosomal aberrations in vitro without metabolic activation and in vivo in hematopoietic and renal cells. As a part of a collaborative study by the Mammalian Mutagenicity Study group, which is a subgroup of the Japanese Environmental Mutagen Society, we administered KBrO3 to rats orally for 4, 14, and 28 days and examined the micronucleated (MNed) cell frequency in the liver, glandular stomach, colon, and bone marrow to confirm whether the genotoxic carcinogen targeting other than liver and gastrointestinal (GI) tract was detected by the repeated dose liver and GI tract micronucleus (MN) assays. In our study, animals treated with KBrO3 showed some signs of toxicity in the kidney and/or stomach. KBrO3 did not increase the frequency of MNed cells in the liver and colon in any of the repeated dose studies. However, KBrO3 increased the frequency of MNed cells in the glandular stomach and bone marrow. Additionally, the MNed cell frequency in the glandular stomach was not significantly affected by the difference in the length of the administration period. These results suggest that performing the MN assay using the glandular stomach, which is the first tissue to contact agents after oral ingestion, is useful for evaluating the genotoxic potential of chemicals and that the glandular stomach MN assay could be integrated into general toxicity studies. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Intra- and Intersession Repeatability of an Optical Quality and Intraocular Scattering Measurement System in Children.

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    Mi Tian

    Full Text Available To evaluate intra- and intersession repeatability of objective optical quality and intraocular scattering measurements with a double-pass system in children.Forty-two eyes of 42 children were included in the study. An optical quality analysis system (OQAS was used to measure optical quality parameters, including modulation transfer function cutoff frequency (MTFcutoff, Strehl ratio (SR, OQAS values (OV at 3 different contrasts and objective scatter index (OSI. Three measurement sessions with 10-min intervals were operated by the same technician, and in each session four consecutive measurements were obtained.Mean values for MTFcutoff, SR and OSI were 46.85 ± 7.45cpd, 0.27 ± 0.06 and 0.34 ± 0.22 respectively. 1 The intraclass correlation coefficients were ranged from 0.89 to 0.97 and coefficients of variation from 0.06 to 0.16 for all the parameters in the first session; the relative repeatability were 11.1% (MTFcutoff, 22.5% (SR, 10.9% (OV100%, 16.6% (OV2%, 22.4% (OV9% and 56.3% (OSI. Similar results were found in the second and third sessions. 2 Bland-Altman analysis showed that narrow 95% confidence intervals (compared between the first and second sessions ranged from -5.42 to 5.28 (MTFcutoff, -0.05 to 0.07 (SR, -0.18 to 0.18 (OV100%, -0.26 to 0.29 (OV20%, -0.33 to 0.39 (OV9% and -0.11 to 0.09 (OSI; the comparison between any two of the three sessions showed similar results.Measurements of optical quality and intraocular scattering in children by the double-pass system showed good intra- and intersession repeatability. Retinal image quality is high and intraocular scattering is low in children.

  15. Effects of complexity and intensity on sensory specific satiety and food acceptance after repeated consumption

    NARCIS (Netherlands)

    Weijzen, P.L.G.; Zandstra, E.H.; Graaf, de C.

    2008-01-01

    The objectives of the present work were (1) to study the effects of complexity and intensity of foods on sensory specific satiety (SSS) and their acceptance after repeated consumption, and (2) to determine the predictive value of SSS for acceptance over repeated consumption. Two studies were

  16. DNA triplet repeats mediate heterochromatin-protein-1-sensitive variegated gene silencing.

    Science.gov (United States)

    Saveliev, Alexander; Everett, Christopher; Sharpe, Tammy; Webster, Zoë; Festenstein, Richard

    2003-04-24

    Gene repression is crucial to the maintenance of differentiated cell types in multicellular organisms, whereas aberrant silencing can lead to disease. The organization of DNA into chromatin and heterochromatin is implicated in gene silencing. In chromatin, DNA wraps around histones, creating nucleosomes. Further condensation of chromatin, associated with large blocks of repetitive DNA sequences, is known as heterochromatin. Position effect variegation (PEV) occurs when a gene is located abnormally close to heterochromatin, silencing the affected gene in a proportion of cells. Here we show that the relatively short triplet-repeat expansions found in myotonic dystrophy and Friedreich's ataxia confer variegation of expression on a linked transgene in mice. Silencing was correlated with a decrease in promoter accessibility and was enhanced by the classical PEV modifier heterochromatin protein 1 (HP1). Notably, triplet-repeat-associated variegation was not restricted to classical heterochromatic regions but occurred irrespective of chromosomal location. Because the phenomenon described here shares important features with PEV, the mechanisms underlying heterochromatin-mediated silencing might have a role in gene regulation at many sites throughout the mammalian genome and modulate the extent of gene silencing and hence severity in several triplet-repeat diseases.

  17. Clinical oversight and the avoidance of repeat induced abortion.

    Science.gov (United States)

    Jacovetty, Erica L; Clare, Camille A; Squire, Mary-Beatrice; Kubal, Keshar P; Liou, Sherry; Inchiosa, Mario A

    2018-06-03

    To evaluate the impact of patient counseling, demographics, and contraceptive methods on repeat induced abortion in women attending family planning clinics. A retrospective chart review of repeat induced abortions was performed. The analysis included patients with an initial induced abortion obtained between January 1, 2001, and March 31, 2014, at New York City Health + Hospitals/Metropolitan. The duration of involvement in the family planning program, the use of contraceptive interventions, and 18 patient factors were analyzed for their correlation with the incidence of repeat induced abortions per year of follow-up. A decreased rate of repeat induced abortions was associated with a longer duration of clinical oversight (r 2 =0.449, Pabortions. By determining the patient characteristics that most influence repeat induced abortion rates, providers can best choose the most efficacious method of contraception available. © 2018 International Federation of Gynecology and Obstetrics.

  18. Advantages and disadvantages : longitudinal vs. repeated cross-section surveys

    Science.gov (United States)

    1996-06-20

    The benefits of a longitudinal analysis over a repeated cross-sectional study include increased statistical power and the capability to estimate a greater range of conditional probabilities. With the Puget Sound Transportation Panel (PSTP), and any s...

  19. The effectiveness of eye-closure in repeated interviews

    NARCIS (Netherlands)

    Vredeveldt, A.; Baddeley, A.D.; Hitch, G.J.

    2014-01-01

    Purpose Closing the eyes during recall can help witnesses remember more about a witnessed event. This study examined the effectiveness of eye-closure in a repeated recall paradigm with immediate free recall followed 1 week later by both free and cued recall. We examined whether eye-closure was more

  20. Repeatability and Reproducibility in Proteomic Identifications by Liquid Chromatography—Tandem Mass Spectrometry

    Science.gov (United States)

    Tabb, David L.; Vega-Montoto, Lorenzo; Rudnick, Paul A.; Variyath, Asokan Mulayath; Ham, Amy-Joan L.; Bunk, David M.; Kilpatrick, Lisa E.; Billheimer, Dean D.; Blackman, Ronald K.; Cardasis, Helene L.; Carr, Steven A.; Clauser, Karl R.; Jaffe, Jacob D.; Kowalski, Kevin A.; Neubert, Thomas A.; Regnier, Fred E.; Schilling, Birgit; Tegeler, Tony J.; Wang, Mu; Wang, Pei; Whiteaker, Jeffrey R.; Zimmerman, Lisa J.; Fisher, Susan J.; Gibson, Bradford W.; Kinsinger, Christopher R.; Mesri, Mehdi; Rodriguez, Henry; Stein, Steven E.; Tempst, Paul; Paulovich, Amanda G.; Liebler, Daniel C.; Spiegelman, Cliff

    2009-01-01

    The complexity of proteomic instrumentation for LC-MS/MS introduces many possible sources of variability. Data-dependent sampling of peptides constitutes a stochastic element at the heart of discovery proteomics. Although this variation impacts the identification of peptides, proteomic identifications are far from completely random. In this study, we analyzed interlaboratory data sets from the NCI Clinical Proteomic Technology Assessment for Cancer to examine repeatability and reproducibility in peptide and protein identifications. Included data spanned 144 LC-MS/MS experiments on four Thermo LTQ and four Orbitrap instruments. Samples included yeast lysate, the NCI-20 defined dynamic range protein mix, and the Sigma UPS 1 defined equimolar protein mix. Some of our findings reinforced conventional wisdom, such as repeatability and reproducibility being higher for proteins than for peptides. Most lessons from the data, however, were more subtle. Orbitraps proved capable of higher repeatability and reproducibility, but aberrant performance occasionally erased these gains. Even the simplest protein digestions yielded more peptide ions than LC-MS/MS could identify during a single experiment. We observed that peptide lists from pairs of technical replicates overlapped by 35–60%, giving a range for peptide-level repeatability in these experiments. Sample complexity did not appear to affect peptide identification repeatability, even as numbers of identified spectra changed by an order of magnitude. Statistical analysis of protein spectral counts revealed greater stability across technical replicates for Orbitraps, making them superior to LTQ instruments for biomarker candidate discovery. The most repeatable peptides were those corresponding to conventional tryptic cleavage sites, those that produced intense MS signals, and those that resulted from proteins generating many distinct peptides. Reproducibility among different instruments of the same type lagged behind

  1. Optimization of sequence alignment for simple sequence repeat regions

    Directory of Open Access Journals (Sweden)

    Ogbonnaya Francis C

    2011-07-01

    Full Text Available Abstract Background Microsatellites, or simple sequence repeats (SSRs, are tandemly repeated DNA sequences, including tandem copies of specific sequences no longer than six bases, that are distributed in the genome. SSR has been used as a molecular marker because it is easy to detect and is used in a range of applications, including genetic diversity, genome mapping, and marker assisted selection. It is also very mutable because of slipping in the DNA polymerase during DNA replication. This unique mutation increases the insertion/deletion (INDELs mutation frequency to a high ratio - more than other types of molecular markers such as single nucleotide polymorphism (SNPs. SNPs are more frequent than INDELs. Therefore, all designed algorithms for sequence alignment fit the vast majority of the genomic sequence without considering microsatellite regions, as unique sequences that require special consideration. The old algorithm is limited in its application because there are many overlaps between different repeat units which result in false evolutionary relationships. Findings To overcome the limitation of the aligning algorithm when dealing with SSR loci, a new algorithm was developed using PERL script with a Tk graphical interface. This program is based on aligning sequences after determining the repeated units first, and the last SSR nucleotides positions. This results in a shifting process according to the inserted repeated unit type. When studying the phylogenic relations before and after applying the new algorithm, many differences in the trees were obtained by increasing the SSR length and complexity. However, less distance between different linage had been observed after applying the new algorithm. Conclusions The new algorithm produces better estimates for aligning SSR loci because it reflects more reliable evolutionary relations between different linages. It reduces overlapping during SSR alignment, which results in a more realistic

  2. Results of repeated transsphenoidal surgery in Cushing's disease. Long-term follow-up.

    Science.gov (United States)

    Valderrábano, Pablo; Aller, Javier; García-Valdecasas, Leopoldo; García-Uría, José; Martín, Laura; Palacios, Nuria; Estrada, Javier

    2014-04-01

    Transsphenoidal surgery (TSS) is the treatment of choice for Cushing's disease (CD). However, the best treatment option when hypercortisolism persists or recurs remains unknown. The aim of this study was to analyze the short and long-term outcome of repeat TSS in this situation and to search for response predictors. Data from 26 patients with persistent (n=11) or recurrent (n=15) hypercortisolism who underwent repeat surgery by a single neurosurgeon between 1982 and 2009 were retrospectively analyzed. Remission was defined as normalization of urinary free cortisol (UFC) levels, and recurrence as presence of elevated UFC levels after having achieved remission. The following potential outcome predictors were analyzed: adrenal status (persistence or recurrence) after initial TSS, tumor identification in imaging tests, degree of hypercortisolism before repeat TSS, same/different surgeon in both TSS, and time to repeat surgery. Immediate postoperative remission was achieved in 12 patients (46.2%). Five of the 10 patients with available follow-up data relapsed after surgery (median time to recurrence, 13 months). New hormone deficiencies were seen in seven patients (37%), and two patients had cerebrospinal fluid leakage. No other major complications occurred. None of the preoperative factors analyzed was predictive of surgical outcome. When compared to initial surgery, repeat TSS for CD is associated to a lower remission rate and a higher risk of recurrence and complications. Further studies are needed to define outcome predictors. Copyright © 2013 SEEN. Published by Elsevier Espana. All rights reserved.

  3. DNA fingerprinting of Mycobacterium leprae strains using variable number tandem repeat (VNTR) - fragment length analysis (FLA).

    Science.gov (United States)

    Jensen, Ronald W; Rivest, Jason; Li, Wei; Vissa, Varalakshmi

    2011-07-15

    The study of the transmission of leprosy is particularly difficult since the causative agent, Mycobacterium leprae, cannot be cultured in the laboratory. The only sources of the bacteria are leprosy patients, and experimentally infected armadillos and nude mice. Thus, many of the methods used in modern epidemiology are not available for the study of leprosy. Despite an extensive global drug treatment program for leprosy implemented by the WHO, leprosy remains endemic in many countries with approximately 250,000 new cases each year. The entire M. leprae genome has been mapped and many loci have been identified that have repeated segments of 2 or more base pairs (called micro- and minisatellites). Clinical strains of M. leprae may vary in the number of tandem repeated segments (short tandem repeats, STR) at many of these loci. Variable number tandem repeat (VNTR) analysis has been used to distinguish different strains of the leprosy bacilli. Some of the loci appear to be more stable than others, showing less variation in repeat numbers, while others seem to change more rapidly, sometimes in the same patient. While the variability of certain VNTRs has brought up questions regarding their suitability for strain typing, the emerging data suggest that analyzing multiple loci, which are diverse in their stability, can be used as a valuable epidemiological tool. Multiple locus VNTR analysis (MLVA) has been used to study leprosy evolution and transmission in several countries including China, Malawi, the Philippines, and Brazil. MLVA involves multiple steps. First, bacterial DNA is extracted along with host tissue DNA from clinical biopsies or slit skin smears (SSS). The desired loci are then amplified from the extracted DNA via polymerase chain reaction (PCR). Fluorescently-labeled primers for 4-5 different loci are used per reaction, with 18 loci being amplified in a total of four reactions. The PCR products may be subjected to agarose gel electrophoresis to verify the

  4. The effect of repeated stress on KCC2 and NKCC1 immunoreactivity in the hippocampus of female mice

    Directory of Open Access Journals (Sweden)

    Takao Tsukahara

    2016-03-01

    Full Text Available K+–Cl− co-transporter (KCC2 and Na+–K+–2Cl− co-transporter (NKCC1 are the main regulators of neuronal intracellular chloride concentration; altered expression patterns of KCC2 and NKCC1 have been reported in several neurodegenerative diseases. In this paper, we show the effect of repeated stress on KCC2, NKCC1, and serine 940 phosphorylated KCC2 (pKCC2ser940 immunoreactivity.The data were obtained from the hippocampus of female mice using single-plane confocal microscopy images. The mean fluorescence intensity of the perisomatic area of neurons, defined as raw fluorescence intensity (RFI was calculated. Repeated stress (RS resulted in a decrease in perisomatic area of immunoreactive (IR-KCC2 and an increase of the IR-NKCC1. In addition, RS decreased perisomatic IR-pKCC2ser940, corresponding to that of KCC2. The data in this article support the results of a previous study [1] and provide the details of immunohistological methods. Interpretation of the data in this article can be found in “Repeated stress-induced expression pattern alterations of the hippocampal chloride transporters KCC2 and NKCC1 associated with behavioral abnormalities in female mice” by Tsukahara et al. [1]. Keywords: KCC2, NKCC1, repeated stress, IHC

  5. Gun Shows and Gun Violence: Fatally Flawed Study Yields Misleading Results

    Science.gov (United States)

    Hemenway, David; Webster, Daniel; Pierce, Glenn; Braga, Anthony A.

    2010-01-01

    A widely publicized but unpublished study of the relationship between gun shows and gun violence is being cited in debates about the regulation of gun shows and gun commerce. We believe the study is fatally flawed. A working paper entitled “The Effect of Gun Shows on Gun-Related Deaths: Evidence from California and Texas” outlined this study, which found no association between gun shows and gun-related deaths. We believe the study reflects a limited understanding of gun shows and gun markets and is not statistically powered to detect even an implausibly large effect of gun shows on gun violence. In addition, the research contains serious ascertainment and classification errors, produces results that are sensitive to minor specification changes in key variables and in some cases have no face validity, and is contradicted by 1 of its own authors’ prior research. The study should not be used as evidence in formulating gun policy. PMID:20724672

  6. Genotoxic and carcinogenic risks associated with the dietary consumption of repeatedly heated coconut oil.

    Science.gov (United States)

    Srivastava, Smita; Singh, Madhulika; George, Jasmine; Bhui, Kulpreet; Murari Saxena, Anand; Shukla, Yogeshwer

    2010-11-01

    Repeated heating of vegetable oils at high temperatures during cooking is a very common cooking practice. Repeated heating of edible oils can generate a number of compounds, including polycyclic aromatic hydrocarbons (PAH), some of which have been reported to have carcinogenic potential. Consumption of these repeatedly heated oils can pose a serious health hazard. The objectives of the present study were to evaluate the genotoxic and carcinogenic risks associated with the consumption of repeatedly heated coconut oil (RCO), which is one of the commonly consumed cooking and frying medium. The PAH were analysed using HPLC in fresh CO, single-heated CO (SCO) and RCO. Results revealed the presence of certain PAH, known to possess carcinogenic potential, in RCO when compared with SCO. Oral intake of RCO in Wistar rats resulted in a significant induction of aberrant cells (P<0·05) and micronuclei (P<0·05) in a dose-dependent manner. Oxidative stress analysis showed a significant (P<0·05) decrease in the levels of antioxidant enzymes such as superoxide dismutase and catalase with a concurrent increase in reactive oxygen species and lipid peroxidation in the liver. In addition, RCO given alone and along with diethylnitrosamine for 12 weeks induced altered hepatic foci as noticed by alteration in positive (γ-glutamyl transpeptidase and glutathione-S-transferase) and negative (adenosine triphosphatase, alkaline phosphatase and glucose-6-phosphatase) hepatospecific biomarkers. A significant decrease in the relative and absolute hepatic weight of RCO-supplemented rats was recorded (P<0·05). In conclusion, dietary consumption of RCO can cause a genotoxic and preneoplastic change in the liver.

  7. Gender, obesity and repeated elevation of C-reactive protein: data from the CARDIA cohort.

    Directory of Open Access Journals (Sweden)

    Shinya Ishii

    Full Text Available C-reactive Protein (CRP measurements above 10 mg/L have been conventionally treated as acute inflammation and excluded from epidemiologic studies of chronic inflammation. However, recent evidence suggest that such CRP elevations can be seen even with chronic inflammation. The authors assessed 3,300 participants in The Coronary Artery Risk Development in Young Adults study, who had two or more CRP measurements between 1992/3 and 2005/6 to a investigate characteristics associated with repeated CRP elevation above 10 mg/L; b identify subgroups at high risk of repeated elevation; and c investigate the effect of different CRP thresholds on the probability of an elevation being one-time rather than repeated. 225 participants (6.8% had one-time and 103 (3.1% had repeated CRP elevation above 10 mg/L. Repeated elevation was associated with obesity, female gender, low income, and sex hormone use. The probability of an elevation above 10 mg/L being one-time rather than repeated was lowest (51% in women with body mass index above 31 kg/m(2, compared to 82% in others. These findings suggest that CRP elevations above 10 mg/L in obese women are likely to be from chronic rather than acute inflammation, and that CRP thresholds above 10 mg/L may be warranted to distinguish acute from chronic inflammation in obese women.

  8. Distribution and Evolution of Yersinia Leucine-Rich Repeat Proteins

    Science.gov (United States)

    Hu, Yueming; Huang, He; Hui, Xinjie; Cheng, Xi; White, Aaron P.

    2016-01-01

    Leucine-rich repeat (LRR) proteins are widely distributed in bacteria, playing important roles in various protein-protein interaction processes. In Yersinia, the well-characterized type III secreted effector YopM also belongs to the LRR protein family and is encoded by virulence plasmids. However, little has been known about other LRR members encoded by Yersinia genomes or their evolution. In this study, the Yersinia LRR proteins were comprehensively screened, categorized, and compared. The LRR proteins encoded by chromosomes (LRR1 proteins) appeared to be more similar to each other and different from those encoded by plasmids (LRR2 proteins) with regard to repeat-unit length, amino acid composition profile, and gene expression regulation circuits. LRR1 proteins were also different from LRR2 proteins in that the LRR1 proteins contained an E3 ligase domain (NEL domain) in the C-terminal region or an NEL domain-encoding nucleotide relic in flanking genomic sequences. The LRR1 protein-encoding genes (LRR1 genes) varied dramatically and were categorized into 4 subgroups (a to d), with the LRR1a to -c genes evolving from the same ancestor and LRR1d genes evolving from another ancestor. The consensus and ancestor repeat-unit sequences were inferred for different LRR1 protein subgroups by use of a maximum parsimony modeling strategy. Structural modeling disclosed very similar repeat-unit structures between LRR1 and LRR2 proteins despite the different unit lengths and amino acid compositions. Structural constraints may serve as the driving force to explain the observed mutations in the LRR regions. This study suggests that there may be functional variation and lays the foundation for future experiments investigating the functions of the chromosomally encoded LRR proteins of Yersinia. PMID:27217422

  9. Comparative effectiveness of inter-simple sequence repeat and ...

    African Journals Online (AJOL)

    A study to compare the effectiveness of inter-simple sequence repeats (ISSR) and randomly amplified polymorphic DNA (RAPD) profiling was carried out with a total of 65 DNA samples using 12 species of Indian Garcinia. ISSR and RAPD profiling were performed with 19 and 12 primers, respectively. ISSR markers ...

  10. Repeat workers' compensation claims: risk factors, costs and work disability

    Science.gov (United States)

    2011-01-01

    Background The objective of our study was to describe factors associated with repeat workers' compensation claims and to compare the work disability arising in workers with single and multiple compensation claims. Methods All initial injury claims lodged by persons of working age during a five year period (1996 to 2000) and any repeat claims were extracted from workers' compensation administrative data in the state of Victoria, Australia. Groups of workers with single and multiple claims were identified. Descriptive analysis of claims by affliction, bodily location, industry segment, occupation, employer and workplace was undertaken. Survival analysis determined the impact of these variables on the time between the claims. The economic impact and duration of work incapacity associated with initial and repeat claims was compared between groups. Results 37% of persons with an initial claim lodged a second claim. This group contained a significantly greater proportion of males, were younger and more likely to be employed in manual occupations and high-risk industries than those with single claims. 78% of repeat claims were for a second injury. Duration between the claims was shortest when the working conditions had not changed. The initial claims of repeat claimants resulted in significantly (p claims. Conclusions A substantial proportion of injured workers experience a second occupational injury or disease. These workers pose a greater economic burden than those with single claims, and also experience a substantially greater cumulative period of work disability. There is potential to reduce the social, health and economic burden of workplace injury by enacting prevention programs targeted at these workers. PMID:21696637

  11. Isolation and characterization of repeat elements of the oak genome and their application in population analysis

    International Nuclear Information System (INIS)

    Fluch, S.; Burg, K.

    1998-01-01

    Four minisatellite sequence elements have been identified and isolated from the genome of the oak species Quercus petraea and Quercus robur. Minisatellites 1 and 2 are putative members of repeat families, while minisatellites 3 and 4 show repeat length variation among individuals of test populations. A 590 base pair (bp) long element has also been identified which reveals individual-specific autoradiographic patterns when used as probe in Southern hybridisations of genomic oak DNA. (author)

  12. Variable flip angle 3D ultrashort echo time (UTE) T1 mapping of mouse lung: A repeatability assessment.

    Science.gov (United States)

    Alamidi, Daniel F; Smailagic, Amir; Bidar, Abdel W; Parker, Nicole S; Olsson, Marita; Hockings, Paul D; Lagerstrand, Kerstin M; Olsson, Lars E

    2018-03-08

    Lung T 1 is a potential translational biomarker of lung disease. The precision and repeatability of variable flip angle (VFA) T 1 mapping using modern 3D ultrashort echo time (UTE) imaging of the whole lung needs to be established before it can be used to assess response to disease and therapy. To evaluate the feasibility of regional lung T 1 quantification with VFA 3D-UTE and to investigate long- and short-term T 1 repeatability in the lungs of naive mice. Prospective preclinical animal study. Eight naive mice and phantoms. 3D free-breathing radial UTE (8 μs) at 4.7T. VFA 3D-UTE T 1 calculations were validated against T 1 values measured with inversion recovery (IR) in phantoms. Lung T 1 and proton density (S 0 ) measurements of whole lung and muscle were repeated five times over 1 month in free-breathing naive mice. Two consecutive T 1 measurements were performed during one of the imaging sessions. Agreement in T 1 between VFA 3D-UTE and IR in phantoms was assessed using Bland-Altman and Pearson 's correlation analysis. The T 1 repeatability in mice was evaluated using coefficient of variation (CV), repeated-measures analysis of variance (ANOVA), and paired t-test. Good T 1 agreement between the VFA 3D-UTE and IR methods was found in phantoms. T 1 in lung and muscle showed a 5% and 3% CV (1255 ± 63 msec and 1432 ± 42 msec, respectively, mean ± SD) with no changes in T 1 or S 0 over a month. Consecutive measurements resulted in an increase of 2% in both lung T 1 and S 0 . VFA 3D-UTE shows promise as a reliable T 1 mapping method that enables full lung coverage, high signal-to-noise ratio (∼25), and spatial resolution (300 μm) in freely breathing animals. The precision of the VFA 3D-UTE method will enable better design and powering of studies. 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018. © 2018 International Society for Magnetic Resonance in Medicine.

  13. Repeatability of apparent diffusion coefficient and intravoxel incoherent motion parameters at 3.0 Tesla in orbital lesions

    Energy Technology Data Exchange (ETDEWEB)

    Lecler, Augustin [Fondation Ophtalmologique Adolphe de Rothschild, Department of Radiology, Paris (France); Cardiovascular Research Centre - PARCC, Universite Paris Descartes Sorbonne Paris Cite, INSERM UMR-S970, Paris (France); Savatovsky, Julien; Sadik, Jean-Claude; Charbonneau, Frederique; Berges, Olivier [Fondation Ophtalmologique Adolphe de Rothschild, Department of Radiology, Paris (France); Balvay, Daniel [Cardiovascular Research Centre - PARCC, Universite Paris Descartes Sorbonne Paris Cite, INSERM UMR-S970, Paris (France); Zmuda, Mathieu; Galatoire, Olivier [Fondation Ophtalmologique Adolphe de Rothschild, Department of Orbitopalpebral Surgery, Paris (France); Picard, Herve [Fondation Ophtalmologique Adolphe de Rothschild, Clinical Research Unit, Paris (France); Fournier, Laure [Cardiovascular Research Centre - PARCC, Universite Paris Descartes Sorbonne Paris Cite, INSERM UMR-S970, Paris (France); Universite Paris Descartes Sorbonne Paris Cite, Assistance Publique-Hopitaux de Paris, Hopital Europeen Georges Pompidou, Radiology Department, Paris (France)

    2017-12-15

    To evaluate repeatability of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) parameters in the orbit. From December 2015 to March 2016, 22 patients were scanned twice using an IVIM sequence with 15b values (0-2,000 s/mm{sup 2}) at 3.0T. Two readers independently delineated regions of interest in an orbital mass and in different intra-orbital and extra-orbital structures. Short-term test-retest repeatability and inter-observer agreement were assessed using the intra-class correlation coefficient (ICC), the coefficient of variation (CV) and Bland-Altman limits of agreements (BA-LA). Test-retest repeatability of IVIM parameters in the orbital mass was satisfactory for ADC and D (mean CV 12% and 14%, ICC 95% and 93%), poor for f and D*(means CV 43% and 110%, ICC 90% and 65%). Inter-observer repeatability agreement was almost perfect in the orbital mass for all the IVIM parameters (ICC = 95%, 93%, 94% and 90% for ADC, D, f and D*, respectively). IVIM appeared to be a robust tool to measure D in orbital lesions with good repeatability, but this approach showed a poor repeatability of f and D*. (orig.)

  14. Repeatability of apparent diffusion coefficient and intravoxel incoherent motion parameters at 3.0 Tesla in orbital lesions

    International Nuclear Information System (INIS)

    Lecler, Augustin; Savatovsky, Julien; Sadik, Jean-Claude; Charbonneau, Frederique; Berges, Olivier; Balvay, Daniel; Zmuda, Mathieu; Galatoire, Olivier; Picard, Herve; Fournier, Laure

    2017-01-01

    To evaluate repeatability of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) parameters in the orbit. From December 2015 to March 2016, 22 patients were scanned twice using an IVIM sequence with 15b values (0-2,000 s/mm 2 ) at 3.0T. Two readers independently delineated regions of interest in an orbital mass and in different intra-orbital and extra-orbital structures. Short-term test-retest repeatability and inter-observer agreement were assessed using the intra-class correlation coefficient (ICC), the coefficient of variation (CV) and Bland-Altman limits of agreements (BA-LA). Test-retest repeatability of IVIM parameters in the orbital mass was satisfactory for ADC and D (mean CV 12% and 14%, ICC 95% and 93%), poor for f and D*(means CV 43% and 110%, ICC 90% and 65%). Inter-observer repeatability agreement was almost perfect in the orbital mass for all the IVIM parameters (ICC = 95%, 93%, 94% and 90% for ADC, D, f and D*, respectively). IVIM appeared to be a robust tool to measure D in orbital lesions with good repeatability, but this approach showed a poor repeatability of f and D*. (orig.)

  15. An infinitely expandable cloning strategy plus repeat-proof PCR for working with multiple shRNA.

    Directory of Open Access Journals (Sweden)

    Glen John McIntyre

    Full Text Available Vector construction with restriction enzymes (REs typically involves the ligation of a digested donor fragment (insert to a reciprocally digested recipient fragment (vector backbone. Creating a suitable cloning plan becomes increasingly difficult for complex strategies requiring repeated insertions such as constructing multiple short hairpin RNA (shRNA expression vectors for RNA interference (RNAi studies. The problem lies in the reduced availability of suitable RE recognition sites with an increasing number of cloning events and or vector size. This report details a technically simple, directional cloning solution using REs with compatible cohesive ends that are repeatedly destroyed and simultaneously re-introduced with each round of cloning. Donor fragments can be made by PCR or sub-cloned from pre-existing vectors and inserted ad infinitum in any combination. The design incorporates several cloning cores in order to be compatible with as many donor sequences as possible. We show that joining sub-combinations made in parallel is more time-efficient than sequential construction (of one cassette at a time for any combination of 4 or more insertions. Screening for the successful construction of combinations using Taq polymerase based PCR became increasingly difficult with increasing number of repeated sequence elements. A Pfu polymerase based PCR was developed and successfully used to amplify combinations of up to eleven consecutive hairpin expression cassettes. The identified PCR conditions can be beneficial to others working with multiple shRNA or other repeated sequences, and the infinitely expandable cloning strategy serves as a general solution applicable to many cloning scenarios.

  16. Maternal overreactive sympathetic nervous system responses to repeated infant crying predicts risk for impulsive harsh discipline of infants.

    Science.gov (United States)

    Joosen, Katharina J; Mesman, Judi; Bakermans-Kranenburg, Marian J; van Ijzendoorn, Marinus H

    2013-11-01

    Physiological reactivity to repeated infant crying was examined as a predictor of risk for harsh discipline use with 12-month-olds in a longitudinal study with 48 low-income mother-infant dyads. Physiological reactivity was measured while mothers listened to three blocks of infant cry sounds in a standard cry paradigm when their infants were 3 months old. Signs of harsh discipline use were observed during two tasks during a home visit when the infants were 12 months old. Mothers showing signs of harsh discipline (n = 10) with their 12-month-olds were compared to mothers who did not (n = 38) on their sympathetic (skin conductance levels [SCL]) and parasympathetic (respiratory sinus arrhythmia) reactivity to the cry sounds. Results showed a significant interaction effect for sympathetic reactivity only. Mean SCL of harsh-risk mothers showed a significant different response pattern from baseline to crying and onward into the recovery, suggesting that mean SCL of mothers who showed signs of harsh discipline continued to rise across the repeated bouts of cry sounds while, after an initial increase, mean SCL level of the other mothers showed a steady decline. We suggest that harsh parenting is reflected in physiological overreactivity to negative infant signals and discuss our findings from a polyvagal perspective.

  17. Repeatability of Bolus Kinetics Ultrasound Perfusion Imaging for the Quantification of Cerebral Blood Flow

    NARCIS (Netherlands)

    Vinke, Elisabeth J.; Eyding, Jens; de Korte, Chris L.; Slump, Cornelis H.; van der Hoeven, Johannes G.; Hoedemaekers, Cornelia W.E.

    2017-01-01

    Ultrasound perfusion imaging (UPI) can be used for the quantification of cerebral perfusion. In a neuro-intensive care setting, repeated measurements are required to evaluate changes in cerebral perfusion and monitor therapy. The aim of this study was to determine the repeatability of UPI in

  18. Immediate-early gene response to repeated immobilization: Fos protein and arc mRNA levels appear to be less sensitive than c-fos mRNA to adaptation.

    Science.gov (United States)

    Ons, Sheila; Rotllant, David; Marín-Blasco, Ignacio J; Armario, Antonio

    2010-06-01

    Stress exposure resulted in brain induction of immediate-early genes (IEGs), considered as markers of neuronal activation. Upon repeated exposure to the same stressor, reduction of IEG response (adaptation) has been often observed, but there are important discrepancies in literature that may be in part related to the particular IEG and methodology used. We studied the differential pattern of adaptation of the IEGs c-fos and arc (activity-regulated cytoskeleton-associated protein) after repeated exposure to a severe stressor: immobilization on wooden boards (IMO). Rats repeatedly exposed to IMO showed reduced c-fos mRNA levels in response to acute IMO in most brain areas studied: the medial prefrontal cortex (mPFC), lateral septum (LS), medial amygdala (MeA), paraventricular nucleus of the hypothalamus (PVN) and locus coeruleus. In contrast, the number of neurons showing Fos-like immunoreactivity was only reduced in the MeA and the various subregions of the PVN. IMO-induced increases in arc gene expression were restricted to telencephalic regions and reduced by repeated IMO only in the mPFC. Double-labelling in the LS of IMO-exposed rats revealed that arc was expressed in only one-third of Fos+ neurons, suggesting two populations of Fos+ neurons. These data suggest that c-fos mRNA levels are more affected by repeated IMO than corresponding protein, and that arc gene expression does not reflect adaptation in most brain regions, which may be related to its constitutive expression. Therefore, the choice of a particular IEG and the method of measurement are important for proper interpretation of the impact of chronic repeated stress on brain activation.

  19. Analysis of the AHR gene proximal promoter GGGGC-repeat polymorphism in lung, breast, and colon cancer

    International Nuclear Information System (INIS)

    Spink, Barbara C.; Bloom, Michael S.; Wu, Susan; Sell, Stewart; Schneider, Erasmus; Ding, Xinxin; Spink, David C.

    2015-01-01

    The aryl hydrocarbon receptor (AhR) regulates expression of numerous genes, including those of the CYP1 gene family. With the goal of determining factors that control AHR gene expression, our studies are focused on the role of the short tandem repeat polymorphism, (GGGGC) n , located in the proximal promoter of the human AHR gene. When luciferase constructs containing varying GGGGC repeats were transfected into cancer cell lines derived from the lung, colon, and breast, the number of GGGGC repeats affected AHR promoter activity. The number of GGGGC repeats was determined in DNA from 327 humans and from 38 samples representing 5 species of non-human primates. In chimpanzees and 3 species of macaques, only (GGGGC) 2 alleles were observed; however, in western gorilla, (GGGGC) n alleles with n = 2, 4, 5, 6, 7, and 8 were identified. In all human populations examined, the frequency of (GGGGC) n was n = 4 > 5 ≫ 2, 6. When frequencies of the (GGGGC) n alleles in DNA from patients with lung, colon, or breast cancer were evaluated, the occurrence of (GGGGC) 2 was found to be 8-fold more frequent among lung cancer patients in comparison with its incidence in the general population, as represented by New York State neonates. Analysis of matched tumor and non-tumor DNA samples from the same individuals provided no evidence of microsatellite instability. These studies indicate that the (GGGGC) n short tandem repeats are inherited, and that the (GGGGC) 2 allele in the AHR proximal promoter region should be further investigated with regard to its potential association with lung cancer susceptibility. - Highlights: • The AHR proximal promoter contains a polymorphism, (GGGGC) n , where n = 4 > 5 ≫ 2, 6 • Matched tumor and non-tumor DNA did not show (GGGGC) n microsatellite instability • AHR promoter activity of a construct with (GGGGC) 2 was lower than that of (GGGGC) 4 • The frequency of (GGGGC) 2 in lung cancer patients was 8-fold higher than in neonates • The

  20. DNA Replication Dynamics of the GGGGCC Repeat of the C9orf72 Gene.

    Science.gov (United States)

    Thys, Ryan Griffin; Wang, Yuh-Hwa

    2015-11-27

    DNA has the ability to form a variety of secondary structures in addition to the normal B-form DNA, including hairpins and quadruplexes. These structures are implicated in a number of neurological diseases and cancer. Expansion of a GGGGCC repeat located at C9orf72 is associated with familial amyotrophic lateral sclerosis and frontotemporal dementia. This repeat expands from two to 24 copies in normal individuals to several hundreds or thousands of repeats in individuals with the disease. Biochemical studies have demonstrated that as little as four repeats have the ability to form a stable DNA secondary structure known as a G-quadruplex. Quadruplex structures have the ability to disrupt normal DNA processes such as DNA replication and transcription. Here we examine the role of GGGGCC repeat length and orientation on DNA replication using an SV40 replication system in human cells. Replication through GGGGCC repeats leads to a decrease in overall replication efficiency and an increase in instability in a length-dependent manner. Both repeat expansions and contractions are observed, and replication orientation is found to influence the propensity for expansions or contractions. The presence of replication stress, such as low-dose aphidicolin, diminishes replication efficiency but has no effect on instability. Two-dimensional gel electrophoresis analysis demonstrates a replication stall with as few as 20 GGGGCC repeats. These results suggest that replication of the GGGGCC repeat at C9orf72 is perturbed by the presence of expanded repeats, which has the potential to result in further expansion, leading to disease. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Characterisation of the Repeat Breeding Syndrome in Swedish Dairy Cattle

    Directory of Open Access Journals (Sweden)

    Emanuelson U

    2002-06-01

    Full Text Available Repeat breeding (RB, defined as cows failure to conceive from 3 or more regularly spaced services in the absence of detectable abnormalities, is a costly problem for the dairy producer. To elucidate the occurrence of RB in Swedish dairy herds and to identify risk factors of the syndrome totally 57,616 dairy cows in 1,541 herds were investigated based on data from the official Swedish production-, AI- and disease- recording schemes. The characteristics of the RB syndrome were studied on both herd and individual cow level. The effects of risk factors on the herd frequency of RB were studied by logistic regression. A generalised linear mixed model with logit link, and accounting for herd-level variation by including a random effect of herd, was used to study the individual animal risk for RB. The total percentage of RB animals was 10.1% and the median proportion of RB animals in the herds studied was 7.5%. The proportion of RB cows in herds increased with decreased herd sizes with decreased average days from calving to first AI, with increased herd incidence of clinical mastitis, with decreased reproductive disorders, and increased other diseases treated by a veterinarian. On animal level, the risk factors were milk yield, lactation number, difficult calving or dystocia, season at first service, days in milk at first service and veterinary treatment for reproductive disorders before the first service. Cows being an RB animal in the previous lactation had a higher risk of becoming an RB animal also in the present lactation. In conclusion our results show that the repeat breeding syndrome is a multifactorial problem involving a number of extrinsic factors as well as intrinsic factors coupled to the individual animal.

  2. Simple sequence repeat marker development and genetic mapping ...

    Indian Academy of Sciences (India)

    polymorphic SSR (simple sequence repeats) markers from libraries enriched for GA, CAA and AAT repeats, as well as 6 ... ers for quinoa was the development of a genetic linkage map ...... Weber J. L. 1990 Informativeness of human (dC-dA)n.

  3. Making assessments while taking repeated risks: a pattern of multiple response pathways.

    Science.gov (United States)

    Pleskac, Timothy J; Wershbale, Avishai

    2014-02-01

    Beyond simply a decision process, repeated risky decisions also require a number of cognitive processes including learning, search and exploration, and attention. In this article, we examine how multiple response pathways develop over repeated risky decisions. Using the Balloon Analogue Risk Task (BART) as a case study, we show that 2 different response pathways emerge over the course of the task. The assessment pathway is a slower, more controlled pathway where participants deliberate over taking a risk. The 2nd pathway is a faster, more automatic process where no deliberation occurs. Results imply the slower assessment pathway is taken as choice conflict increases and that the faster automatic response is a learned response. Based on these results, we modify an existing formal cognitive model of decision making during the BART to account for these dual response pathways. The slower more deliberative response process is modeled with a sequential sampling process where evidence is accumulated to a threshold, while the other response is given automatically. We show that adolescents with conduct disorder and substance use disorder symptoms not only evaluate risks differently during the BART but also differ in the rate at which they develop the more automatic response. More broadly, our results suggest cognitive models of judgment decision making need to transition from treating observed decisions as the result of a single response pathway to the result of multiple response pathways that change and develop over time.

  4. Muscle damage and repeated bout effect induced by enhanced eccentric squats.

    Science.gov (United States)

    Coratella, Giuseppe; Chemello, Alessandro; Schena, Federico

    2016-12-01

    Muscle damage and repeated bout effect have been studied after pure eccentric-only exercise. The aim of this study was to evaluate muscle damage and repeated bout effect induced by enhanced eccentric squat exercise using flywheel device. Thirteen healthy males volunteered for this study. Creatine kinase blood activity (CK), quadriceps isometric peak torque and muscle soreness were used as markers of muscle damage. The dependent parameters were measured at baseline, immediately after and each day up to 96 hours after the exercise session. The intervention consisted of 100 repetitions of enhanced eccentric squat exercise using flywheel device. The same protocol was repeated after 4 weeks. After the first bout, CK and muscle soreness were significantly greater (P0.05), while isometric peak torque and muscle soreness returned to values similar to baseline after respectively 48 and 72 hours. All muscle damage markers were significantly lower after second compared to first bout. The enhanced eccentric exercise induced symptoms of muscle damage up to 96 hours. However, it provided muscle protection after the second bout, performed four weeks later. Although it was not eccentric-only exercise, the enhancement of eccentric phase provided muscle protection.

  5. Repeating pneumatic pellet injector in JAERI

    Energy Technology Data Exchange (ETDEWEB)

    Kasai, Satoshi; Hasegawa, Kouichi; Suzuki, Sadaaki; Miura, Yukitoshi (Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment); Oda, Yasushi; Onozuka, Masanori; Tsujimura, Seiichi.

    1992-09-01

    A repeating pneumatic pellet injector has been developed and constructed at Japan Atomic Energy Research Institute. This injector can provide repetitive pellet injection to fuel tokamak plasmas for an extended period of time, aiming at the improvement of plasma performance. The pellets with nearly identical speed and mass can be repeatedly injected with a repetition rate of 2-3.3 Hz and a speed of up to 1.7 km/s by controlling the temperature of the cryogenic system, the piston speed and the pressure of the propellant gas. (author).

  6. Repeating pneumatic pellet injector in JAERI

    International Nuclear Information System (INIS)

    Kasai, Satoshi; Hasegawa, Kouichi; Suzuki, Sadaaki; Miura, Yukitoshi; Oda, Yasushi; Onozuka, Masanori; Tsujimura, Seiichi.

    1992-09-01

    A repeating pneumatic pellet injector has been developed and constructed at Japan Atomic Energy Research Institute. This injector can provide repetitive pellet injection to fuel tokamak plasmas for an extended period of time, aiming at the improvement of plasma performance. The pellets with nearly identical speed and mass can be repeatedly injected with a repetition rate of 2-3.3 Hz and a speed of up to 1.7 km/s by controlling the temperature of the cryogenic system, the piston speed and the pressure of the propellant gas. (author)

  7. Ultrastructure of canine meninges after repeated epidural injection of S(+)-ketamine.

    Science.gov (United States)

    Acosta, Alinne; Gomar, Carmen; Bombí, Josep A; Graça, Dominguita L; Garrido, Marta; Krauspenhar, Cristina

    2006-01-01

    The safety of ketamine when administered by the spinal route must be confirmed in various animal species before it is approved for use in humans. This study evaluates the ultrastructure of canine meninges after repeated doses of epidural S(+)-ketamine. Five dogs received S(+)-ketamine 5%, 1 mg/kg, twice a day for 10 days through an epidural catheter with its tip located at the L5 level. One dog received the same volume of normal saline at the same times. The spinal cord and meninges were processed for histopathological and ultrastructural studies. Clinical effects were assessed after each injection. Motor and sensory block appeared after each injection of S(+)-ketamine, but not in the dog receiving saline. No signs of clinical or neurologic alterations were observed. Using light microscopy, no meningeal layer showed alterations except focal infiltration at the catheter tip level by macrophages, lymphocytes, and a few mast cells. The cells of different layers were studied by electron microscopy and interpreted according to data from human and other animal species because no ultrastructural description of the canine meninges is currently available. There were no cellular signs of inflammation, phagocytosis, or degeneration in meningeal layers and no signs of atrophy, compression, or demyelinization in the areas of dorsal root ganglia and spinal cord around the arachnoid. These findings were common for dogs receiving S(+)-ketamine and the dog receiving saline. Repeated doses of epidural S(+)-ketamine 5%, 1 mg/kg, twice a day for 10 days was not associated to cellular alterations in canine meninges.

  8. Evaluation of repeated dose micronucleus assays of the liver using N-nitrosopyrrolidine: a report of the collaborative study by CSGMT/JEMS.MMS.

    Science.gov (United States)

    Ogawa, Izumi; Hagioa, Soichiro; Furukawa, Satoshi; Abe, Masayoshi; Kuroda, Yusuke; Hayashi, Seigo; Wako, Yumi; Kawasako, Kazufumi

    2015-03-01

    The repeated dose liver micronucleus (RDLMN) assay has the potential to detect liver carcinogens, and can be integrated into a general toxicological study. To assess the performance of the assay, N-nitrosopyrrolidine (NPYR), a genotoxic hepatocarcinogen, was tested in 14- or 28-day RDLMN assays. NPYR was orally administered to rats at a daily dose of 25, 50 or 100 mg/kg. One day after the last administration, a portion of the liver was removed and hepatocyte micronucleus (MN) specimens were prepared by the new method recently established by Narumi et al. In addition, a bone marrow MN assay and a histopathological examination of the liver were conducted. The detection of Phospho-Histone H3 was performed by immunohistochemistry to evaluate the proliferation rate of hepatocytes. The results showed significant increase in the number of micronucleated hepatocytes and Phospho-Histone H3-positive cells from the lowest dose in both 14- and 28-day RDLMN assays. On the other hand, the bone marrow MN assay yielded a negative result, which was in accordance with the existing report of the bone marrow MN assay using mice. Upon histopathological examination, inflammatory lesions and hypertrophy were noted, which may explain the increase in the hepatocyte proliferation and the enhancement of MN induction by NPYR. Our findings indicate that the RDLMN assay could be a useful tool for comprehensive risk assessment of carcinogenicity by providing information on both genotoxicity and histopathology when integrated into a general repeat dosing toxicity assay.

  9. Repeated oral administration of capsaicin increases anxiety-like ...

    Indian Academy of Sciences (India)

    This study was conducted to examine the psycho-emotional effects of repeated oral exposure to capsaicin, the principal active component of chili peppers. Each rat received 1 mL of 0.02% capsaicin into its oral cavity daily, and was subjected to behavioural tests following 10 daily administrations of capsaicin. Stereotypy ...

  10. Simple sequence repeat (SSR)-based genetic variability among ...

    African Journals Online (AJOL)

    The objective of this study was to compare if simple sequence repeat (SSR) markers could correctly identify peanut genotypes with difference in specific leaf weight (SLW) and relative water content (RWC). Four peanut genotypes and two water regimes (FC and 1/3 available water; 1/3 AW) were arranged in factorial ...

  11. Study on a 4-Week Recovery Test of Sweet Bee Venom after a 13-Week, Repeated, Intramuscular Dose Toxicity Test in Sprague-Dawley Rats

    Directory of Open Access Journals (Sweden)

    Chungsan Lim

    2014-06-01

    Full Text Available Objectives:This study was performed to check for reversibility in the changes induced by a 13-week, repeated, dose toxicity test of Sweet Bee Venom (SBV in Sprague-Dawley (SD rats. Methods:Fifteen male and 15 female SD rats were treated with 0.28 mg/kg of SBV (high-dosage group and the same numbers of male and female SD rats were treated with 0.2 mL/kg of normal saline (control group for 13 weeks. We selected five male and five female SD rats from the high-dosage group and the same numbers of male and female SD rats from the control group, and we observed these rats for four weeks. We conducted body-weight measurements, ophthalmic examinations, urinalyses and hematology, biochemistry, histology tests. Results:(1 Hyperemia and movement disorder were observed in the 13-week, repeated, dose toxicity test, but these symptoms were not observed during the recovery period. (2 The rats in the high-dose group showed no significant changes in weight compared to the control group. (3 No significant differences in the ophthalmic parameters, urine analyses, complete blood cell counts (CBCs, and biochemistry were observed among the recovery groups. (4 No changes in organ weights were observed during the recovery period. (5 Histological examination of the thigh muscle indicated cell infiltration, inflammation, degeneration, necrosis of muscle fiber, and fibrosis during the treatment period, but these changes were not observed during the recovery period. The fatty liver change that was observed during the toxicity test was not observed during the recovery period. No other organ abnormalities were observed. Conclusion:The changes that occurred during the 13-week, repeated, dose toxicity test are reversible, and SBV can be safely used as a treatment modality.

  12. CAG repeat length variation in the polymerase gamma (POLG) gene: effect on semen quality

    NARCIS (Netherlands)

    Westerveld, G. H.; Kaaij-Visser, L.; Tanck, M.; van der Veen, F.; Repping, S.

    2008-01-01

    Several case-control studies have investigated the effect of CAG repeat length variation in the POLG gene on male fertility and semen quality. Some described an association between the homozygous not10 CAG-repeat genotype and male subfertility and/or reduced semen quality, whereas others did not.

  13. SSRscanner: a program for reporting distribution and exact location of simple sequence repeats.

    Science.gov (United States)

    Anwar, Tamanna; Khan, Asad U

    2006-02-20

    Simple sequence repeats (SSRs) have become important molecular markers for a broad range of applications, such as genome mapping and characterization, phenotype mapping, marker assisted selection of crop plants and a range of molecular ecology and diversity studies. These repeated DNA sequences are found in both prokaryotes and eukaryotes. They are distributed almost at random throughout the genome, ranging from mononucleotide to trinucleotide repeats. They are also found at longer lengths (> 6 repeating units) of tracts. Most of the computer programs that find SSRs do not report its exact position. A computer program SSRscanner was written to find out distribution, frequency and exact location of each SSR in the genome. SSRscanner is user friendly. It can search repeats of any length and produce outputs with their exact position on chromosome and their frequency of occurrence in the sequence. This program has been written in PERL and is freely available for non-commercial users by request from the authors. Please contact the authors by E-mail: huzzi99@hotmail.com.

  14. Aging, recall and recognition: a study on the sensitivity of the University of Southern California Repeatable Episodic Memory Test (USC-REMT).

    Science.gov (United States)

    Parker, Elizabeth S; Landau, Susan M; Whipple, Stephen C; Schwartz, Barbara L

    2004-05-01

    This study examines the sensitivity of the University of Southern California Repeatable Episodic Memory Test (USC-REMT) to the effects of aging in a sample of 112 men and women from 18 to 93 years old. Two new recognition measures, yes-no and forced-choice, were developed to supplement the original USC-REMT which measured only free-recall. Free-recall, yes-no recognition and forced-choice recognition were sensitive to age effects, with free-recall being the most sensitive. The seven recall and recognition lists can be used interchangeably. The data indicate that the USC-REMT is worthy of consideration when there is a need for a brief, screening tool of various memory functions, particularly when there is interest in memory changes over time and repeated assessments.

  15. Polymorphism of CRISPR shows separated natural groupings of Shigella subtypes and evidence of horizontal transfer of CRISPR

    Science.gov (United States)

    Yang, Chaojie; Li, Peng; Su, Wenli; Li, Hao; Liu, Hongbo; Yang, Guang; Xie, Jing; Yi, Shengjie; Wang, Jian; Cui, Xianyan; Wu, Zhihao; Wang, Ligui; Hao, Rongzhang; Jia, Leili; Qiu, Shaofu; Song, Hongbin

    2015-01-01

    Clustered, regularly interspaced, short palindromic repeats (CRISPR) act as an adaptive RNA-mediated immune mechanism in bacteria. They can also be used for identification and evolutionary studies based on polymorphisms within the CRISPR locus. We amplified and analyzed 6 CRISPR loci from 237 Shigella strains belonging to the 4 species groups, as well as 13 Escherichia coli strains. The CRISPR-associated (cas) gene sequence arrays of these strains were screened and compared. The CRISPR sequences from Shigella were conserved among subtypes, suggesting that CRISPR may represent a new identification tool for the detection and discrimination of Shigella species. Secondary structure analysis showed a different stem-loop structure at the terminal repeat, suggesting a distinct recognition mechanism in the formation of crRNA. In addition, the presence of “self-target” spacers and polymorphisms within CRISPR in Shigella indicated a selective pressure for inhibition of this system, which has the potential to damage “self DNA.” Homology analysis of spacers showed that CRISPR might be involved in the regulation of virulence transmission. Phylogenetic analysis based on CRISPR sequences from Shigella and E. coli indicated that although phenotypic properties maintain convergent evolution, the 4 Shigella species do not represent natural groupings. Surprisingly, comparative analysis of Shigella repeats with other species provided new evidence for CRISPR horizontal transfer. Our results suggested that CRISPR analysis is applicable for the detection of Shigella species and for investigation of evolutionary relationships. PMID:26327282

  16. Polymorphism of CRISPR shows separated natural groupings of Shigella subtypes and evidence of horizontal transfer of CRISPR.

    Science.gov (United States)

    Yang, Chaojie; Li, Peng; Su, Wenli; Li, Hao; Liu, Hongbo; Yang, Guang; Xie, Jing; Yi, Shengjie; Wang, Jian; Cui, Xianyan; Wu, Zhihao; Wang, Ligui; Hao, Rongzhang; Jia, Leili; Qiu, Shaofu; Song, Hongbin

    2015-01-01

    Clustered, regularly interspaced, short palindromic repeats (CRISPR) act as an adaptive RNA-mediated immune mechanism in bacteria. They can also be used for identification and evolutionary studies based on polymorphisms within the CRISPR locus. We amplified and analyzed 6 CRISPR loci from 237 Shigella strains belonging to the 4 species groups, as well as 13 Escherichia coli strains. The CRISPR-associated (cas) gene sequence arrays of these strains were screened and compared. The CRISPR sequences from Shigella were conserved among subtypes, suggesting that CRISPR may represent a new identification tool for the detection and discrimination of Shigella species. Secondary structure analysis showed a different stem-loop structure at the terminal repeat, suggesting a distinct recognition mechanism in the formation of crRNA. In addition, the presence of "self-target" spacers and polymorphisms within CRISPR in Shigella indicated a selective pressure for inhibition of this system, which has the potential to damage "self DNA." Homology analysis of spacers showed that CRISPR might be involved in the regulation of virulence transmission. Phylogenetic analysis based on CRISPR sequences from Shigella and E. coli indicated that although phenotypic properties maintain convergent evolution, the 4 Shigella species do not represent natural groupings. Surprisingly, comparative analysis of Shigella repeats with other species provided new evidence for CRISPR horizontal transfer. Our results suggested that CRISPR analysis is applicable for the detection of Shigella species and for investigation of evolutionary relationships.

  17. The Study on the Ferrokinetics and Acquired Immunity in Repeated Hookworm Infections

    International Nuclear Information System (INIS)

    Lee, Mun Ho; Lee, Pyl Ung

    1967-01-01

    In order to confirm whether acquired immunity or resistance can be developed by the repeated hookworm infections, the 150 mature actively moving filariform ancylostoma duodenale larvae obtained from the severe hookworm anemia patients were orally given to 8 healthy volunteers in three divided doses, 50 in each, at 5 day interval. Also the hematological changes as well as several ferrokinetics using 59 Fe were done and were compared with 10 controls. The clinical symptoms and signs were checked every day for the first 3 weeks and then twice weekly until the end of the experiment. The appearance of the ova in the stool was examined by the formalin ether method and the ova was counted by the Stoll's method. The following laboratory tests were done:1) Red blood cell count, venous blood hematocrit (micromethod), hemoglobin count (cyanomethemoglobin method) were checked every 5 to 7 day interval. 2) Plasma iron concentration (Barkan's modified method) was determined every 2 to 3 week interval. 3) Radioisotope studies:a) Ferrokinetics: Huff et al and Bothwell's method were applied. Erythropoietic Index (% of normal)= [ S ubject's turnover/100 ml whole bloodX100 ] over [ A verage normal turnover/100 ml whole blood ] b) Quantitative measurement of the gastrointestinal absorption of iron:Radioiron ( 59 Fe) balance method was applied. c) Determination of the plasma erythropoietin activity: Fried's method was applied. Following were the results: 1) The serum iron level was lower. The red cell volume was decreased, but with relative increase of plasma volume. 2) The plasma iron disappearance time was accelerated and the plasma iron turnover rate was decreased. The red cell iron turnover rate was markedly increased, while all of the red cell iron concentration, circulating red cell iron, plasma iron pool were decreased. The daily iron pool turnover and red cell renewal rate were increased. 3) The erythropoietic index, erythropoietin activity and intestinal absorption of iron

  18. The Study on the Ferrokinetics and Acquired Immunity in Repeated Hookworm Infections

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Mun Ho; Lee, Pyl Ung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1967-09-15

    In order to confirm whether acquired immunity or resistance can be developed by the repeated hookworm infections, the 150 mature actively moving filariform ancylostoma duodenale larvae obtained from the severe hookworm anemia patients were orally given to 8 healthy volunteers in three divided doses, 50 in each, at 5 day interval. Also the hematological changes as well as several ferrokinetics using {sup 59}Fe were done and were compared with 10 controls. The clinical symptoms and signs were checked every day for the first 3 weeks and then twice weekly until the end of the experiment. The appearance of the ova in the stool was examined by the formalin ether method and the ova was counted by the Stoll's method. The following laboratory tests were done:1) Red blood cell count, venous blood hematocrit (micromethod), hemoglobin count (cyanomethemoglobin method) were checked every 5 to 7 day interval. 2) Plasma iron concentration (Barkan's modified method) was determined every 2 to 3 week interval. 3) Radioisotope studies:a) Ferrokinetics: Huff et al and Bothwell's method were applied. Erythropoietic Index (% of normal)= ['Subject's turnover/100 ml whole bloodX100'] over ['Average normal turnover/100 ml whole blood'] b) Quantitative measurement of the gastrointestinal absorption of iron:Radioiron ({sup 59}Fe) balance method was applied. c) Determination of the plasma erythropoietin activity: Fried's method was applied. Following were the results: 1) The serum iron level was lower. The red cell volume was decreased, but with relative increase of plasma volume. 2) The plasma iron disappearance time was accelerated and the plasma iron turnover rate was decreased. The red cell iron turnover rate was markedly increased, while all of the red cell iron concentration, circulating red cell iron, plasma iron pool were decreased. The daily iron pool turnover and red cell renewal rate were increased. 3) The erythropoietic index, erythropoietin activity and intestinal absorption of

  19. Repeatability of Ophtha Top topography and comparison with IOL-Master and LenstarLS900 in cataract patients

    Directory of Open Access Journals (Sweden)

    Sha-Sha Yu

    2017-11-01

    Full Text Available AIM: To determine the repeatability of Ophtha Top topography and assess the consistency with intraocular lens (IOL-Master and LenstarLS900 (Lenstar in measuring corneal parameters among cataract patients. METHODS: Totally 125 eyes were enrolled. Corneas were successively measured with Ophtha Top, IOL-Master and Lenstar at least three times. The flattest meridian power (Kf, the steepest meridian power (Ks, mean power (Km, J0 and J45 were recorded. Intra-class correlation coefficients (ICCs, the coefficient of variance (COV, within subject standard deviation (Sw, and test-retest repeatability (2.77Sw were adopted to determine the repeatability. The 95% limit of agreement (95%LOA and Bland-Altman plots were used to assess comparability. RESULTS: Repeatability of Ophtha Top topography for measuring corneal parameters showed the ICCs were all above 0.93, 2.77Sw was lower than 0.31, and the COV of the Kf and Ks was lower than 0.25. The keratometric readings with Ophtha Top topography were flatter than with the IOL-Master and Lenstar devices, while the Pearson correlation coefficients were over 0.97. The J0 and J45 with Ophtha Top topography were smaller compared with Lenstar and IOL-Master, while was comparable between Lenstar and IOL-Master. CONCLUSION: Ophtha Top topography shows excellent repeatability for measuring corneal parameters. However, differences between the Ophtha TOP topography and Lenstar, IOL-Master both in cornea curvature and the astigmatism should be noted clinically.

  20. Intra-rater repeatability of the Oxford foot model in healthy children in different stages of the foot roll over process during gait

    DEFF Research Database (Denmark)

    Curtis, D J; Bencke, J; Stebbins, J A

    2009-01-01

    BACKGROUND: The repeatability of the Oxford foot model has been reported, but possible variations in the repeatability during the foot roll over process have not been examined. The aim of this study was to determine the relative and absolute repeatability of the model for each stage of the foot...... roll over process during gait and to compare foot kinematic data from this study with that from another centre as a preliminary examination of the model's inter-centre repeatability and validity. METHOD: Eight healthy children were tested twice at the gait laboratory. Foot kinematics from this study...... were plotted against those from an earlier repeatability study and repeatability statistics calculated for the three rockers of stance phase and swing phase. RESULTS: Foot kinematics from this study and an earlier repeatability study produced similar kinematic patterns and joint angle ranges...

  1. Exploring antecedents of consumer satisfaction and repeated search behavior on e-health information.

    Science.gov (United States)

    Lee, Yun Jung; Park, Jungkun; Widdows, Richard

    2009-03-01

    E-health information has become an important resource for people seeking health information. Even though many studies have been conducted to examine the quality of e-health information, only a few studies have explored the effects of the information seekers' motivations on the perceived quality of e-health information. There is even less information about repeated searches for e-health information after the users' initial experience of e-health information use. Using an online survey of information seekers, 252 e-health information users' responses were collected. The research examines the relationship among motivation, perceived quality, satisfaction, and intention to repeat-search e-health information. The results identify motivations to search e-health information and confirm the relationship among motivation, perceived quality dimensions, and satisfaction and intention to repeat searches for e-health information.

  2. 40 CFR 1065.305 - Verifications for accuracy, repeatability, and noise.

    Science.gov (United States)

    2010-07-01

    ..., repeatability, and noise. 1065.305 Section 1065.305 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Verifications for accuracy, repeatability, and noise. (a) This section describes how to determine the accuracy, repeatability, and noise of an instrument. Table 1 of § 1065.205 specifies recommended values for individual...

  3. Heterogeneous Diversity of Spacers within CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)

    Science.gov (United States)

    He, Jiankui; Deem, Michael W.

    2010-09-01

    Clustered regularly interspaced short palindromic repeats (CRISPR) in bacterial and archaeal DNA have recently been shown to be a new type of antiviral immune system in these organisms. We here study the diversity of spacers in CRISPR under selective pressure. We propose a population dynamics model that explains the biological observation that the leader-proximal end of CRISPR is more diversified and the leader-distal end of CRISPR is more conserved. This result is shown to be in agreement with recent experiments. Our results show that the CRISPR spacer structure is influenced by and provides a record of the viral challenges that bacteria face.

  4. Low numbers of repeat units in variable number of tandem repeats (VNTR) regions of white spot syndrome virus are correlated with disease outbreaks.

    Science.gov (United States)

    Hoa, T T T; Zwart, M P; Phuong, N T; de Jong, M C M; Vlak, J M

    2012-11-01

    White spot syndrome virus (WSSV) is the most important pathogen in shrimp farming systems worldwide including the Mekong Delta, Vietnam. The genome of WSSV is characterized by the presence of two major 'indel regions' found at ORF14/15 and ORF23/24 (WSSV-Thailand) and three regions with variable number tandem repeats (VNTR) located in ORF75, ORF94 and ORF125. In the current study, we investigated whether or not the number of repeat units in the VNTRs correlates with virus outbreak status and/or shrimp farming practice. We analysed 662 WSSV samples from individual WSSV-infected Penaeus monodon shrimp from 104 ponds collected from two important shrimp farming regions of the Mekong Delta: Ca Mau and Bac Lieu. Using this large data set and statistical analysis, we found that for ORF94 and ORF125, the mean number of repeat units (RUs) in VNTRs was significantly lower in disease outbreak ponds than in non-outbreak ponds. Although a higher mean RU number was observed in the improved-extensive system than in the rice-shrimp or semi-intensive systems, these differences were not significant. VNTR sequences are thus not only useful markers for studying WSSV genotypes and populations, but specific VNTR variants also correlate with disease outbreaks in shrimp farming systems. © 2012 Blackwell Publishing Ltd.

  5. Two tandemly repeated telomere-associated sequences in Nicotiana plumbaginifolia.

    Science.gov (United States)

    Chen, C M; Wang, C T; Wang, C J; Ho, C H; Kao, Y Y; Chen, C C

    1997-12-01

    Two tandemly repeated telomere-associated sequences, NP3R and NP4R, have been isolated from Nicotiana plumbaginifolia. The length of a repeating unit for NP3R and NP4R is 165 and 180 nucleotides respectively. The abundance of NP3R, NP4R and telomeric repeats is, respectively, 8.4 x 10(4), 6 x 10(3) and 1.5 x 10(6) copies per haploid genome of N. plumbaginifolia. Fluorescence in situ hybridization revealed that NP3R is located at the ends and/or in interstitial regions of all 10 chromosomes and NP4R on the terminal regions of three chromosomes in the haploid genome of N. plumbaginifolia. Sequence homology search revealed that not only are NP3R and NP4R homologous to HRS60 and GRS, respectively, two tandem repeats isolated from N. tabacum, but that NP3R and NP4R are also related to each other, suggesting that they originated from a common ancestral sequence. The role of these repeated sequences in chromosome healing is discussed based on the observation that two to three copies of a telomere-similar sequence were present in each repeating unit of NP3R and NP4R.

  6. First worldwide proficiency study on variable-number tandem-repeat typing of Mycobacterium tuberculosis complex strains.

    NARCIS (Netherlands)

    Beer, J.L. de; Kremer, K.; Kodmon, C.; Supply, P.; Soolingen, D. van

    2012-01-01

    Although variable-number tandem-repeat (VNTR) typing has gained recognition as the new standard for the DNA fingerprinting of Mycobacterium tuberculosis complex (MTBC) isolates, external quality control programs have not yet been developed. Therefore, we organized the first multicenter proficiency

  7. A simple repeat polymorphism in the MITF-M promoter is a key regulator of white spotting in dogs.

    Directory of Open Access Journals (Sweden)

    Izabella Baranowska Körberg

    Full Text Available The white spotting locus (S in dogs is colocalized with the MITF (microphtalmia-associated transcription factor gene. The phenotypic effects of the four S alleles range from solid colour (S to extreme white spotting (s(w. We have investigated four candidate mutations associated with the s(w allele, a SINE insertion, a SNP at a conserved site and a simple repeat polymorphism all associated with the MITF-M promoter as well as a 12 base pair deletion in exon 1B. The variants associated with white spotting at all four loci were also found among wolves and we conclude that none of these could be a sole causal mutation, at least not for extreme white spotting. We propose that the three canine white spotting alleles are not caused by three independent mutations but represent haplotype effects due to different combinations of causal polymorphisms. The simple repeat polymorphism showed extensive diversity both in dogs and wolves, and allele-sharing was common between wolves and white spotted dogs but was non-existent between solid and spotted dogs as well as between wolves and solid dogs. This finding was unexpected as Solid is assumed to be the wild-type allele. The data indicate that the simple repeat polymorphism has been a target for selection during dog domestication and breed formation. We also evaluated the significance of the three MITF-M associated polymorphisms with a Luciferase assay, and found conclusive evidence that the simple repeat polymorphism affects promoter activity. Three alleles associated with white spotting gave consistently lower promoter activity compared with the allele associated with solid colour. We propose that the simple repeat polymorphism affects cooperativity between transcription factors binding on either flanking sides of the repeat. Thus, both genetic and functional evidence show that the simple repeat polymorphism is a key regulator of white spotting in dogs.

  8. The effect of repeated melting of zircaloy-4 to the distribution of volatile constituents

    International Nuclear Information System (INIS)

    Johneri, E.; Wijaksana; Badruzzaman, M.

    1996-01-01

    The effect of repeated fusion on the composition and distribution of zircaloy volatile elemental constituents (especially Sn) has been investigated. The results showed that the higher the number of repeated fusion is, the more evenly distributed the constituents are, but the composition decreased until reached constant values. This phenomenon occurred due to the relatively faster diffusion movement of one element compared to the others. Further investigation needs to be done to find other proofs of the phenomenon. Moreover, continued research is in demand in order to answer technological problems regarding the zircaloy production and metal alloy production in general. (author)

  9. Minocycline Prevents Muscular Pain Hypersensitivity and Cutaneous Allodynia Produced by Repeated Intramuscular Injections of Hypertonic Saline in Healthy Human Participants.

    Science.gov (United States)

    Samour, Mohamad Samir; Nagi, Saad Saulat; Shortland, Peter John; Mahns, David Anthony

    2017-08-01

    Minocycline, a glial suppressor, prevents behavioral hypersensitivities in animal models of peripheral nerve injury. However, clinical trials of minocycline in human studies have produced mixed results. This study addressed 2 questions: can repeated injections of hypertonic saline (HS) in humans induce persistent hypersensitivity? Can pretreatment with minocycline, a tetracycline antibiotic with microglial inhibitory effects, prevent the onset of hypersensitivity? Twenty-seven healthy participants took part in this double-blind, placebo-controlled study, consisting of 6 test sessions across 2 weeks. At the beginning of every session, pressure-pain thresholds of the anterior muscle compartment of both legs were measured to determine the region distribution and intensity of muscle soreness. To measure changes in thermal sensitivity in the skin overlying the anterior muscle compartment of both legs, quantitative sensory testing was used to measure the cutaneous thermal thresholds (cold sensation, cold pain, warm sensation, and heat pain) and a mild cooling stimulus was applied to assess the presence of cold allodynia. To induce ongoing hypersensitivity, repeated injections of HS were administered into the right tibialis anterior muscle at 48-hour intervals. In the final 2 sessions (days 9 and 14), only sensory assessments were done to plot the recovery after cessation of HS administrations and drug washout. By day 9, nontreated participants experienced a significant bilateral increase in muscle soreness (P minocycline-treated participants experienced a bilateral 70% alleviation in muscle soreness (P minocycline-treated participants showed cold allodynia. This study showed that repeated injections of HS can induce a hypersensitivity that outlasts the acute response, and the development of this hypersensitivity can be reliably attenuated with minocycline pretreatment. Four repeated injections of HS at 48-hour intervals induce a state of persistent hypersensitivity in

  10. The development of the micro-solid propellant thruster array with improved repeatability

    International Nuclear Information System (INIS)

    Seo, Daeban; Kwon, Sejin; Lee, Jongkwang

    2012-01-01

    This paper presents the development of a micro-solid propellant thruster array with improved repeatability. The repeatability and low performance variation of each thruster unit with a high ignition success rate is essential in micro-solid propellant thruster array. To date, the study on the improvement of the repeatability has not yet been reported. As the first step for this study, we propose a new type of micro igniter, using a glass wafer called the heater-contact micro igniter. This igniter is also designed to improve the ignition characteristics of a glass-based micro igniter. The prototype of the igniter array is designed and fabricated to establish its fabrication process and to conduct its performance evaluation. Through the firing test, the performance of the heater-contact micro igniter is verified. The 5 × 5 sized micro-solid propellant thruster array is designed and fabricated applying the developed heater-contact igniter. The measured average thrust of each thruster unit is 2.542 N, and calculated standard deviation is 0.369 N. The calculated average total impulse and its standard deviation are 0.182 and 0.04 mNs, respectively. Based on these results, the improvement of repeatability is verified. Finally, the ignition control system of the micro-thruster array is developed. (paper)

  11. 47 CFR 80.469 - Maritime mobile repeater stations in Alaska.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Maritime mobile repeater stations in Alaska. 80... RADIO SERVICES STATIONS IN THE MARITIME SERVICES Public Coast Stations Use of Telephony § 80.469 Maritime mobile repeater stations in Alaska. (a) Maritime mobile repeater stations are authorized to extend...

  12. 5meCpG epigenetic marks neighboring a primate-conserved core promoter short tandem repeat indicate X-chromosome inactivation.

    Science.gov (United States)

    Machado, Filipe Brum; Machado, Fabricio Brum; Faria, Milena Amendro; Lovatel, Viviane Lamim; Alves da Silva, Antonio Francisco; Radic, Claudia Pamela; De Brasi, Carlos Daniel; Rios, Álvaro Fabricio Lopes; de Sousa Lopes, Susana Marina Chuva; da Silveira, Leonardo Serafim; Ruiz-Miranda, Carlos Ramon; Ramos, Ester Silveira; Medina-Acosta, Enrique

    2014-01-01

    X-chromosome inactivation (XCI) is the epigenetic transcriptional silencing of an X-chromosome during the early stages of embryonic development in female eutherian mammals. XCI assures monoallelic expression in each cell and compensation for dosage-sensitive X-linked genes between females (XX) and males (XY). DNA methylation at the carbon-5 position of the cytosine pyrimidine ring in the context of a CpG dinucleotide sequence (5meCpG) in promoter regions is a key epigenetic marker for transcriptional gene silencing. Using computational analysis, we revealed an extragenic tandem GAAA repeat 230-bp from the landmark CpG island of the human X-linked retinitis pigmentosa 2 RP2 promoter whose 5meCpG status correlates with XCI. We used this RP2 onshore tandem GAAA repeat to develop an allele-specific 5meCpG-based PCR assay that is highly concordant with the human androgen receptor (AR) exonic tandem CAG repeat-based standard HUMARA assay in discriminating active (Xa) from inactive (Xi) X-chromosomes. The RP2 onshore tandem GAAA repeat contains neutral features that are lacking in the AR disease-linked tandem CAG repeat, is highly polymorphic (heterozygosity rates approximately 0.8) and shows minimal variation in the Xa/Xi ratio. The combined informativeness of RP2/AR is approximately 0.97, and this assay excels at determining the 5meCpG status of alleles at the Xp (RP2) and Xq (AR) chromosome arms in a single reaction. These findings are relevant and directly translatable to nonhuman primate models of XCI in which the AR CAG-repeat is monomorphic. We conducted the RP2 onshore tandem GAAA repeat assay in the naturally occurring chimeric New World monkey marmoset (Callitrichidae) and found it to be informative. The RP2 onshore tandem GAAA repeat will facilitate studies on the variable phenotypic expression of dominant and recessive X-linked diseases, epigenetic changes in twins, the physiology of aging hematopoiesis, the pathogenesis of age-related hematopoietic

  13. 5meCpG epigenetic marks neighboring a primate-conserved core promoter short tandem repeat indicate X-chromosome inactivation.

    Directory of Open Access Journals (Sweden)

    Filipe Brum Machado

    Full Text Available X-chromosome inactivation (XCI is the epigenetic transcriptional silencing of an X-chromosome during the early stages of embryonic development in female eutherian mammals. XCI assures monoallelic expression in each cell and compensation for dosage-sensitive X-linked genes between females (XX and males (XY. DNA methylation at the carbon-5 position of the cytosine pyrimidine ring in the context of a CpG dinucleotide sequence (5meCpG in promoter regions is a key epigenetic marker for transcriptional gene silencing. Using computational analysis, we revealed an extragenic tandem GAAA repeat 230-bp from the landmark CpG island of the human X-linked retinitis pigmentosa 2 RP2 promoter whose 5meCpG status correlates with XCI. We used this RP2 onshore tandem GAAA repeat to develop an allele-specific 5meCpG-based PCR assay that is highly concordant with the human androgen receptor (AR exonic tandem CAG repeat-based standard HUMARA assay in discriminating active (Xa from inactive (Xi X-chromosomes. The RP2 onshore tandem GAAA repeat contains neutral features that are lacking in the AR disease-linked tandem CAG repeat, is highly polymorphic (heterozygosity rates approximately 0.8 and shows minimal variation in the Xa/Xi ratio. The combined informativeness of RP2/AR is approximately 0.97, and this assay excels at determining the 5meCpG status of alleles at the Xp (RP2 and Xq (AR chromosome arms in a single reaction. These findings are relevant and directly translatable to nonhuman primate models of XCI in which the AR CAG-repeat is monomorphic. We conducted the RP2 onshore tandem GAAA repeat assay in the naturally occurring chimeric New World monkey marmoset (Callitrichidae and found it to be informative. The RP2 onshore tandem GAAA repeat will facilitate studies on the variable phenotypic expression of dominant and recessive X-linked diseases, epigenetic changes in twins, the physiology of aging hematopoiesis, the pathogenesis of age-related hematopoietic

  14. Thrombospondin-1 type 1 repeats in a model of inflammatory bowel disease: transcript profile and therapeutic effects.

    Directory of Open Access Journals (Sweden)

    Zenaida P Lopez-Dee

    Full Text Available Thrombospondin-1 (TSP-1 is a matricellular protein with regulatory functions in inflammation and cancer. The type 1 repeats (TSR domains of TSP-1 have been shown to interact with a wide range of proteins that result in the anti-angiogenic and anti-tumor properties of TSP-1. To ascertain possible functions and evaluate potential therapeutic effects of TSRs in inflammatory bowel disease, we conducted clinical, histological and microarray analyses on a mouse model of induced colitis. We used dextran sulfate sodium (DSS to induce colitis in wild-type (WT mice for 7 days. Simultaneously, mice were injected with either saline or one form of TSP-1 derived recombinant proteins, containing either (1 the three type 1 repeats of the TSP-1 (3TSR, (2 the second type 1 repeat (TSR2, or (3 TSR2 with the RFK sequence (TSR2+RFK. Total RNA isolated from the mice colons were processed and hybridized to mouse arrays. Array data were validated by real-time qPCR and immunohistochemistry. Histological and disease indices reveal that the mice treated with the TSRs show different patterns of leukocytic infiltration and that 3TSR treatment was the most effective in decreasing inflammation in DSS-induced colitis. Transcriptional profiling revealed differentially expressed (DE genes, with the 3TSR-treated mice showing the least deviation from the WT-water controls. In conclusion, this study shows that 3TSR treatment is effective in attenuating the inflammatory response to DSS injury. In addition, the transcriptomics work unveils novel genetic data that suggest beneficial application of the TSR domains in inflammatory bowel disease.

  15. Differential Regulation of Strand-Specific Transcripts from Arabidopsis Centromeric Satellite Repeats.

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available Centromeres interact with the spindle apparatus to enable chromosome disjunction and typically contain thousands of tandemly arranged satellite repeats interspersed with retrotransposons. While their role has been obscure, centromeric repeats are epigenetically modified and centromere specification has a strong epigenetic component. In the yeast Schizosaccharomyces pombe, long heterochromatic repeats are transcribed and contribute to centromere function via RNA interference (RNAi. In the higher plant Arabidopsis thaliana, as in mammalian cells, centromeric satellite repeats are short (180 base pairs, are found in thousands of tandem copies, and are methylated. We have found transcripts from both strands of canonical, bulk Arabidopsis repeats. At least one subfamily of 180-base pair repeats is transcribed from only one strand and regulated by RNAi and histone modification. A second subfamily of repeats is also silenced, but silencing is lost on both strands in mutants in the CpG DNA methyltransferase MET1, the histone deacetylase HDA6/SIL1, or the chromatin remodeling ATPase DDM1. This regulation is due to transcription from Athila2 retrotransposons, which integrate in both orientations relative to the repeats, and differs between strains of Arabidopsis. Silencing lost in met1 or hda6 is reestablished in backcrosses to wild-type, but silencing lost in RNAi mutants and ddm1 is not. Twenty-four-nucleotide small interfering RNAs from centromeric repeats are retained in met1 and hda6, but not in ddm1, and may have a role in this epigenetic inheritance. Histone H3 lysine-9 dimethylation is associated with both classes of repeats. We propose roles for transcribed repeats in the epigenetic inheritance and evolution of centromeres.

  16. Variable-number-of-tandem-repeats analysis of genetic diversity in Pasteuria ramosa.

    Science.gov (United States)

    Mouton, L; Ebert, D

    2008-05-01

    Variable-number-of-tandem-repeats (VNTR) markers are increasingly being used in population genetic studies of bacteria. They were recently developed for Pasteuria ramosa, an endobacterium that infects Daphnia species. In the present study, we genotyped P. ramosa in 18 infected hosts from the United Kingdom, Belgium, and two lakes in the United States using seven VNTR markers. Two Daphnia species were collected: D. magna and D. dentifera. Six loci showed length polymorphism, with as many as five alleles identified for a single locus. Similarity coefficient calculations showed that the extent of genetic variation between pairs of isolates within populations differed according to the population, but it was always less than the genetic distances among populations. Analysis of the genetic distances performed using principal component analysis revealed strong clustering by location of origin, but not by host Daphnia species. Our study demonstrated that the VNTR markers available for P. ramosa are informative in revealing genetic differences within and among populations and may therefore become an important tool for providing detailed analysis of population genetics and epidemiology.

  17. Annually repeated influenza vaccination improves humoral responses to several influenza virus strains in healthy elderly

    NARCIS (Netherlands)

    I.A. de Bruijn (Iris); E.J. Remarque (Edmond); W.E.Ph. Beyer (Walter); S. le Cessie (Saskia); N. Masurel (Nic); G.L. Ligthart (Gerard)

    1997-01-01

    textabstractThe benefit of annually repeated influenza vaccination on antibody formation is still under debate. In this study the effect of annually repeated influenza vaccination on haemagglutination inhibiting (HI) antibody formation in the elderly is investigated. Between 1990 and 1993 healthy

  18. Local toxicity of benzalkonium chloride in ophthalmic solutions following repeated applications.

    Science.gov (United States)

    Okahara, Akihiko; Kawazu, Kouichi

    2013-01-01

    We performed repeated toxicity studies of benzalkonium chloride (BAK)-containing vehicles of ophthalmic solutions in monkeys and rabbits to assess the local toxicity of BAK after repeated applications on the ocular surface. Local toxicity of BAK was evaluated by toxicity studies in which a 0.01% BAK-containing vehicle was applied twice/day for 52 weeks, 4 times/day for 39 weeks, or 6 times/day for 13 weeks, or in which a 0.005% BAK-containing vehicle was applied 6 times/day for 52 weeks or twice/day for 4 weeks in monkeys. Local toxicity of BAK was also evaluated where a 0.01% BAK-containing vehicle was applied 6 times/day for 6 weeks, or a 0.005% BAK-containing vehicle was applied twice/day for 39 weeks or 8 times/day for 4 weeks in rabbits. These doses were chosen because BAK is generally used at concentrations up to 0.01% in ophthalmic solutions. The BAK-containing vehicle did not cause ophthalmological changes suggestive of irritation, allergy, or corneal damage. We also did not observe any histopathological changes in the eyeball, eyelid, lacrimal gland, and nasal cavity, with repeated applications of BAK for up to 52 weeks, up to 8 times/day, or at concentrations up to 0.01%, in monkeys and rabbits. Our results suggest that BAK in concentrations up to 0.01% in ophthalmic solution is non-toxic to the eyeball, its accessory organs, and the nasal cavity after long repeated applications.

  19. Liking of health-functional foods containing lupin kernel fibre following repeated consumption in a dietary intervention setting.

    Science.gov (United States)

    Hall, Ramon S; Baxter, Amynta L; Fryirs, Cathy; Johnson, Stuart K

    2010-10-01

    Liking of a particular food after repeated consumption may be reduced, limiting the effectiveness of health-functional foods requiring on-going consumption to deliver their benefits. This study examined the effect of repeated consumption of foods containing the novel ingredient, Australian sweet lupin (Lupinus angustifolius) kernel fibre (LKFibre) on sensory acceptability in the dietary intervention setting. In a single-blind randomised crossover 4-week intervention, participants consumed both control and equivalent LKFibre-containing products daily on separate interventions separated by a 4-week period on habitual diet. Seven products: muesli, bread, muffin, chocolate brownie, chocolate milk drink, pasta and instant mashed potato were assessed twice (days 4 and 18 of intervention), by 38 participants for appearance, texture, flavour and general acceptability using a structured graphic hedonic scale. Overall the results showed there was no reduction (P=0.594) in general acceptability of LKFibre foods after repeated consumption, suggesting potential for long-term consumption. The control food products were however generally preferred (P<0.001) over the LKFibre foods; the mean difference for general acceptability between being <6% (0.82cm) of the 15cm hedonic scale used, suggesting LKF addition did not severely affect product palatability.

  20. Test-retest repeatability of myocardial blood flow and infarct size using 11C-acetate micro-PET imaging in mice

    International Nuclear Information System (INIS)

    Croteau, Etienne; Renaud, Jennifer M.; McDonald, Matthew; Klein, Ran; DaSilva, Jean N.; Beanlands, Rob S.B.; DeKemp, Robert A.

    2015-01-01

    Global and regional responses of absolute myocardial blood flow index (iMBF) are used as surrogate markers to assess response to therapies in coronary artery disease. In this study, we assessed the test-retest repeatability of iMBF imaging, and the accuracy of infarct sizing in mice using 11 C-acetate PET. 11 C-Acetate cardiac PET images were acquired in healthy controls, endothelial nitric oxide synthase (eNOS) knockout transgenic mice, and mice after myocardial infarction (MI) to estimate global and regional iMBF, and myocardial infarct size compared to 18 F-FDG PET and ex-vivo histology results. Global test-retest iMBF values had good coefficients of repeatability (CR) in healthy mice, eNOS knockout mice and normally perfused regions in MI mice (CR = 1.6, 2.0 and 1.5 mL/min/g, respectively). Infarct size measured on 11 C-acetate iMBF images was also repeatable (CR = 17 %) and showed a good correlation with the infarct sizes found on 18 F-FDG PET and histopathology (r 2 > 0.77; p < 0.05). 11 C-Acetate micro-PET assessment of iMBF and infarct size is repeatable and suitable for serial investigation of coronary artery disease progression and therapy. (orig.)