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Sample records for background translocation frequencies

  1. Measurement of background translocation frequencies in individuals with clones

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    Wade, M.J.

    1996-08-01

    In the leukemia case the unseparated B and T lymphocytes had a high translocation frequency even after 0.0014, respectively. After purging all clones from the data, the translocation frequencies for Bio 8 and Bio 23 were 0.00750.0014 and 0.0073 metaphases were scored for chromosomal aberrations,, specifically reciprocal translocations, using fluorescence in situ hybridization (FISH). Metaphase spreads were used from two healthy, unexposed individuals (not exposed to radiation, chemotherapy or radiotherapy) and one early B- precursor acute lymphocytic leukemia (ALL) patient (metaphase spreads from both separated T lymphocytes and unseparated B and T lymphocytes were scored). All three individuals had an abnormally high translocation frequency. The high translocation frequencies resulted from clonal expansion of specific translocated chromosomes. I show in this thesis that by purging (discounting or removing) clones from the data of unexposed individuals, one can obtain true background translocation frequencies. In two cases, Bio 8 and Bio 23, the measured translocation frequency for chromosomes 1, 2 and 4 was 0.0124 purging all of the clones from the data. This high translocation frequency may be due to a low frequency of some clones and may not be recognized. The separated T lymphocytes had a higher translocation frequency than expected.

  2. The effects of translocations on recombination frequency in Caenorhabditis elegans.

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    McKim, K S; Howell, A M; Rose, A M

    1988-12-01

    In the nematode Caenorhabditis elegans, recombination suppression in translocation heterozygotes is severe and extensive. We have examined the meiotic properties of two translocations involving chromosome I, szT1(I;X) and hT1(I;V). No recombination was observed in either of these translocation heterozygotes along the left (let-362-unc-13) 17 map units of chromosome I. Using half-translocations as free duplications, we mapped the breakpoints of szT1 and hT1. The boundaries of crossover suppression coincided with the physical breakpoints. We propose that DNA sequences at the right end of chromosome I facilitate pairing and recombination. We use the data from translocations of other chromosomes to map the location of pairing sites on four other chromosomes. hT1 and szT1 differed markedly in their effect on recombination adjacent to the crossover suppressed region. hT1 had no effect on recombination in the adjacent interval. In contrast, the 0.8 map unit interval immediately adjacent to the szT1(I;X) breakpoint on chromosome I increased to 2.5 map units in translocation heterozygotes. This increase occurs in a chromosomal interval which can be expanded by treatment with radiation. These results are consistent with the suggestion that the szT1(I) breakpoint is in a region of DNA in which meiotic recombination is suppressed relative to the genomic average. We propose that DNA sequences disrupted by the szT1 translocation are responsible for determining the frequency of meiotic recombination in the vicinity of the breakpoint.

  3. Translocation frequency of double-stranded DNA through a solid-state nanopore

    CERN Document Server

    Bell, Nicholas A W; Keyser, Ulrich F

    2015-01-01

    Solid-state nanopores are single molecule sensors that measure changes in ionic current as charged polymers such as DNA pass through. Here, we present comprehensive experiments on the length, voltage and salt dependence of the frequency of double-stranded DNA translocations through conical quartz nanopores with mean opening diameter 15 nm. We observe an entropic barrier limited, length dependent translocation frequency at 4M LiCl salt concentration and a drift-dominated, length independent translocation frequency at 1M KCl salt concentration. These observations are described by a unifying convection-diffusion equation which includes the contribution of an entropic barrier for polymer entry.

  4. Stability of the translocation frequency following whole-body irradiation measured in rhesus monkeys

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    Lucas, J. N.; Hill, F. S.; Burk, C. E.; Cox, A. B.; Straume, T.

    1996-01-01

    Chromosome translocations are persistent indicators of prior exposure to ionizing radiation and the development of 'chromosome painting' to efficiently detect translocations has resulted in a powerful biological dosimetry tool for radiation dose reconstruction. However, the actual stability of the translocation frequency with time after exposure must be measured before it can be used reliably to obtain doses for individuals exposed years or decades previously. Human chromosome painting probes were used here to measure reciprocal translocation frequencies in cells from two tissues of 8 rhesus monkeys (Macaca mulatta) irradiated almost three decades previously. Six of the monkeys were exposed in 1965 to whole-body (fully penetrating) radiation and two were unexposed controls. The primates were irradiated as juveniles to single doses of 0.56, 1.13, 2.00, or 2.25 Gy. Blood lymphocytes (and skin fibroblasts from one individual) were obtained for cytogenetic analysis in 1993, near the end of the animals' lifespans. Results show identical dose-response relationships 28 y after exposure in vivo and immediately after exposure in vitro. Because chromosome aberrations are induced with identical frequencies in vivo and in vitro, these results demonstrate that the translocation frequencies induced in 1965 have not changed significantly during the almost three decades since exposure. Finally, our emerging biodosimetry data for individual radiation workers are now confirming the utility of reciprocal translocations measured by FISH in radiation dose reconstruction.

  5. Analysis of chromosome translocation frequency after a single CT scan in adults.

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    Abe, Yu; Miura, Tomisato; Yoshida, Mitsuaki A; Ujiie, Risa; Kurosu, Yumiko; Kato, Nagisa; Katafuchi, Atsushi; Tsuyama, Naohiro; Kawamura, Fumihiko; Ohba, Takashi; Inamasu, Tomoko; Shishido, Fumio; Noji, Hideyoshi; Ogawa, Kazuei; Yokouchi, Hiroshi; Kanazawa, Kenya; Ishida, Takashi; Muto, Satoshi; Ohsugi, Jun; Suzuki, Hiroyuki; Ishikawa, Tetsuo; Kamiya, Kenji; Sakai, Akira

    2016-06-01

    We recently reported an increase in dicentric chromosome (DIC) formation after a single computed tomography (CT) scan (5.78-60.27 mSv: mean 24.24 mSv) and we recommended analysis of 2000 metaphase cells stained with Giemsa and centromere-FISH for dicentric chromosome assay (DCA) in cases of low-dose radiation exposure. In the present study, we analyzed the frequency of chromosome translocations using stored Carnoy's-fixed lymphocyte specimens from the previous study; these specimens were from 12 patients who were subject to chromosome painting of Chromosomes 1, 2 and 4. Chromosomes 1, 2 and 4 were analyzed in ∼5000 cells, which is equivalent to the whole-genome analysis of almost 2000 cells. The frequency of chromosome translocation was higher than the number of DICs formed, both before and after CT scanning. The frequency of chromosome translocations tended to be higher, but not significantly higher, in patients with a treatment history compared with patients without such a history. However, in contrast to the results for DIC formation, the frequency of translocations detected before and after the CT scan did not differ significantly. Therefore, analysis of chromosome translocation may not be a suitable assay for detecting chromosome aberrations in cases of low-dose radiation exposure from a CT scan. A significant increase in the frequency of chromosome translocations was not likely to be detected due to the high baseline before the CT scan; the high and variable frequency of translocations was probably due to multiple confounding factors in adults.

  6. Modulation of the Object/Background Interaction by Spatial Frequency

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    Yanju Ren

    2011-05-01

    Full Text Available With regard to the relationship between object and background perception in the natural scene images, functional isolation hypothesis and interactive hypothesis were proposed. Based on previous studies, the present study investigated the role of spatial frequency in the relationship between object and background perception in the natural scene images. In three experiments, participants reported the object, background, or both after seeing each picture for 500 ms followed by a mask. The authors found that (a backgrounds were identified more accurately when they contained a consistent rather than an inconsistent object, independently of spatial frequency; (b objects were identified more accurately in a consistent than an inconsistent background under the condition of low spatial frequencies but not high spatial frequencies; (c spatial frequency modulation remained when both objects and backgrounds were reported simultaneously. The authors conclude that object/background interaction is partially dependent on spatial frequency.

  7. Characterization of Common Chromosomal Translocations and Their Frequencies in Acute Myeloid Leukemia Patients of Northwest Iran

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    Elnaz Amanollahi Kamaneh

    2016-04-01

    Full Text Available Objective: Detection of chromosomal translocations has an important role in diagnosis and treatment of hematological disorders. We aimed to evaluate the 46 new cases of de novo acute myeloid leukemia (AML patients for common translocations and to assess the effect of geographic and ethnic differences on their frequencies. Materials and Methods: In this descriptive study, reverse transcriptase-polymerase chain reaction (RT-PCR was used on 46 fresh bone marrow or peripheral blood samples to detect translocations t (8; 21, t (15; 17, t (9; 11 and inv (16. Patients were classified using the French-American-British (FAB criteria in to eight sub-groups (M0-M7. Immunophenotyping and biochemical test results of patients were compared with RT-PCR results. Results: Our patients were relatively young with a mean age of 44 years. AML was relatively predominant in female patients (54.3% and most of patients belonged to AML-M2. Translocation t (8; 21 had the highest frequency (13% and t (15; 17 with 2.7% incidence was the second most frequent. CD19 as an immunophenotypic marker was at a relatively high frequency (50% in cases with t (8; 21, and patients with this translocation had a specific immunophenotypic pattern of complete expression of CD45, CD38, CD34, CD33 and HLA-DR. Conclusion: Similarities and differences of results in Iran with different parts of the world can be explained with ethnic and geographic factors in characterizations of AML. Recognition of these factors especially in other comprehensive studies may aid better diagnosis and management of this disease.

  8. The effect of wheat-rye translocation 1BL.1RS in a different quality genetic background on biological traits in wheat

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    Dimitrijević Miodrag

    2008-01-01

    Full Text Available A sample of 139 varieties of common wheat (Triticum aestivum L., predominantly Serbian winter wheat varieties originated in the Institute of Field and Vegetable Crops in Novi Sad, has been examined for presence of 1BL/1RS wheat-rye translocation. Two genotype groups consisted of varieties possessing and lacking the translocation have been compared. Stem rust, leaf rust, powdery mildew as well as, winter hardiness were studied. The influence of 1BL/1RS translocation was also studied in a light of wheat seed storage protein (glutenin and gliadin genetic background composition. Genotypes having the translocation appeared to be more tolerant to stem rust, and leaf rust, but more susceptible to powdery mildew. These effects were slightly modified depending on the examined genetic background, but the effect of the rye 1RS translocated chromosome arm was the main cause for the observed differences.

  9. Background frequencies for residue variability estimates: BLOSUM revisited

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    Reš I

    2007-12-01

    Full Text Available Abstract Background Shannon entropy applied to columns of multiple sequence alignments as a score of residue conservation has proven one of the most fruitful ideas in bioinformatics. This straightforward and intuitively appealing measure clearly shows the regions of a protein under increased evolutionary pressure, highlighting their functional importance. The inability of the column entropy to differentiate between residue types, however, limits its resolution power. Results In this work we suggest generalizing Shannon's expression to a function with similar mathematical properties, that, at the same time, includes observed propensities of residue types to mutate to each other. To do that, we revisit the original construction of BLOSUM matrices, and re-interpret them as mutation probability matrices. These probabilities are then used as background frequencies in the revised residue conservation measure. Conclusion We show that joint entropy with BLOSUM-proportional probabilities as a reference distribution enables detection of protein functional sites comparable in quality to a time-costly maximum-likelihood evolution simulation method (rate4site, and offers greater resolution than the Shannon entropy alone, in particular in the cases when the available sequences are of narrow evolutionary scope.

  10. C-MYC and BCL2 translocation frequency in diffuse large B-cell lymphomas: A study of 97 patients

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    Bahar Akkaya

    2016-01-01

    Full Text Available Purpose: Diffuse large B-cell lymphoma (DLBCL is an aggressive non-Hodgkin lymphoma with marked biologic heterogeneity. MYC and BCL2 rearrangements have been reported in a proportion of DLBCLs, where they may be associated with an adverse clinical outcome. The aim of this study was to determine the frequency of MYC and BCL2 translocations in DLBCL and assess the prognostic impact in DLBCL patients. Materials and Methods:   In the present study, we evaluated the expression patterns of CD 10, BCL6, and MUM 1 by immunohistochemistry in 121 cases with DLBCL in tissue microarray (TMA: 62 cases in germinal center B-cells (GCBs; and 59 cases in activated B-cells (ABCs of which 60 were females and 61 were males. MYC and BCL2 rearrangements were investigated by interphase fluorescence in situ hybridization on TMAs in 97 DLBCLs. Result: MYC rearrangements were observed in 11 of 97 cases. There was no association with other clinical features, including age, sex, and nodal/extranodal disease. MYC rearrangement was associated with significantly worse overall survival (P < 0.01. BCL2 rearrangements were observed in 14 of 97 cases. There was no association with other clinical features including age and sex. BCL2 rearrangement had a worse outcome (P < 0.01. MYC and BCL2 rearrangements were observed in 3 of 97 cases with the age of  53 (female, 53, 63 years old, respectively, died in 24, 18, and 35 months after the diagnosis. Two cases had primary nodal and one case primary extranodal presentations. All these patients had stage IV disease. Conclusion: We concluded that C-MYC and BCL2 may contribute to aggressive transformation, and more mechanism-based therapy should be explored. Targeted therapies involving these rearrangements and its associated pathways may change the fate of DLBCLs. Analysis of MYC gene rearrangement along with BCL2 is critical in the identification of high-risk patients with poor prognosis.

  11. Sensitivity to a Frequency-Dependent Circular Polarization in an Isotropic Stochastic Gravitational Wave Background

    CERN Document Server

    Smith, Tristan L

    2016-01-01

    We calculate the sensitivity to a circular polarization of an isotropic stochastic gravitational wave background (ISGWB) as a function of frequency for ground- and space-based interferometers and observations of the cosmic microwave background. The origin of a circularly polarized ISGWB may be due to exotic primordial physics (i.e., parity violation in the early universe) and may be strongly frequency dependent. We present calculations within a coherent framework which clarifies the basic requirements for sensitivity to circular polarization, in distinction from previous work which focused on each of these techniques separately. We find that the addition of an interferometer with the sensitivity of the Einstein Telescope in the southern hemisphere improves the sensitivity of the ground-based network to circular polarization by about a factor of two. The sensitivity curves presented in this paper make clear that the wide range in frequencies of current and planned observations ($10^{-18}\\ {\\rm Hz} \\lesssim f \\...

  12. Theta frequency background tunes transmission but not summation of spiking responses.

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    Dhanya Parameshwaran

    Full Text Available Hippocampal neurons are known to fire as a function of frequency and phase of spontaneous network rhythms, associated with the animal's behaviour. This dependence is believed to give rise to precise rate and temporal codes. However, it is not well understood how these periodic membrane potential fluctuations affect the integration of synaptic inputs. Here we used sinusoidal current injection to the soma of CA1 pyramidal neurons in the rat brain slice to simulate background oscillations in the physiologically relevant theta and gamma frequency range. We used a detailed compartmental model to show that somatic current injection gave comparable results to more physiological synaptically driven theta rhythms incorporating excitatory input in the dendrites, and inhibitory input near the soma. We systematically varied the phase of synaptic inputs with respect to this background, and recorded changes in response and summation properties of CA1 neurons using whole-cell patch recordings. The response of the cell was dependent on both the phase of synaptic inputs and frequency of the background input. The probability of the cell spiking for a given synaptic input was up to 40% greater during the depolarized phases between 30-135 degrees of theta frequency current injection. Summation gain on the other hand, was not affected either by the background frequency or the phasic afferent inputs. This flat summation gain, coupled with the enhanced spiking probability during depolarized phases of the theta cycle, resulted in enhanced transmission of summed inputs during the same phase window of 30-135 degrees. Overall, our study suggests that although oscillations provide windows of opportunity to selectively boost transmission and EPSP size, summation of synaptic inputs remains unaffected during membrane oscillations.

  13. Low-frequency measurements of the CMB (cosmic microwave background) spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Kogut, A.; Bensadoun, M.; De Amici, G.; Levin, S.; Limon, M.; Smoot, G. (Lawrence Berkeley Lab., CA (USA)); Sironi, G. (Milan Univ. (Italy). Dipt. di Fisica); Bersanelli, M.; Bonelli, G. (Consiglio Nazionale delle Ricerche, Milan (Italy))

    1989-10-01

    As part of an extended program to characterize the spectrum of the cosmic microwave background (CMB) at low frequencies, we have performed multiple measurements from a high-altitude site in California. On average, these measurements suggest a CMB temperature slightly lower than measurements at higher frequencies. Atmospheric conditions and the encroachment of civilization are now significant limitations from our present observing site. In November 1989, we will make new measurements from the South Pole Amnudsen-Scott Station at frequencies 0.82 1.5, 2.5, 3.8, 7.5, and 90 GHz. We discuss recent measurements and indicate improvements from a polar observing site. 11 refs., 2 figs.

  14. Dolphins adjust species-specific frequency parameters to compensate for increasing background noise.

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    Papale, Elena; Gamba, Marco; Perez-Gil, Monica; Martin, Vidal Martel; Giacoma, Cristina

    2015-01-01

    An increase in ocean noise levels could interfere with acoustic communication of marine mammals. In this study we explored the effects of anthropogenic and natural noise on the acoustic properties of a dolphin communication signal, the whistle. A towed array with four elements was used to record environmental background noise and whistles of short-beaked common-, Atlantic spotted- and striped-dolphins in the Canaries archipelago. Four frequency parameters were measured from each whistle, while Sound Pressure Levels (SPL) of the background noise were measured at the central frequencies of seven one-third octave bands, from 5 to 20 kHz. Results show that dolphins increase the whistles' frequency parameters with lower variability in the presence of anthropogenic noise, and increase the end frequency of their whistles when confronted with increasing natural noise. This study provides the first evidence that the synergy among SPLs has a role in shaping the whistles' structure of these three species, with respect to both natural and anthropogenic noise.

  15. Study of electromagnetic backgrounds in the 25-300 MHz frequency band at the South Pole

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    Auffenberg, Jan; Gaisser, Tom; Helbing, Klaus; Karg, Timo; Karle, Albrecht; Kravchenko, Ilya

    2010-01-01

    Extensive air showers are detectable by radio signals with a radio surface detector. A promising theory of the dominant emission process is the coherent synchrotron radiation emitted by e+ e- shower particles in the Earth's magnetic field (geosynchrotron effect). A radio air shower detector can extend IceTop, the air shower detector on top of IceCube. This could increase the sensitivity of IceTop to higher shower energies and for inclined showers significantly. Muons from air showers are a major part of the background of the neutrino telescope IceCube. Thus a surface radio air shower detector could act as a veto detector for this muonic background. Initial radio background measurements with a single antenna in 2007 revealed a continuous electromagnetic background promising a low energy threshold of radio air shower detection. However, short pulsed radio interferences can mimic real signals and have to be identified in the frequency range of interest. These properties of the electromagnetic background was bein...

  16. Multi-frequency survey of background radiations of the Universe. The "Cosmological Gene" project. First results

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    Parijskij, Yu. N.; Mingaliev, M. G.; Nizhel'Skii, N. A.; Bursov, N. N.; Berlin, A. B.; Grechkin, A. A.; Zharov, V. I.; Zhekanis, G. V.; Majorova, E. K.; Semenova, T. A.; Stolyarov, V. A.; Tsybulev, P. G.; Kratov, D. V.; Udovitskii, R. Yu.; Khaikin, V. B.

    2011-10-01

    The results of the first stage of the "Cosmological Gene" project of the Russian Academy of Sciences are reported. These results consist in the accumulation of multi-frequency data in 31 frequency channels in the wavelength interval 1-55 cm with maximum achievable statistical sensitivity limited by the noise of background radio sources at all wavelengths exceeding 1.38 cm. The survey region is determined by constraints 00 h microwave background are reported as well as the contribution of these noise components in millimeter-wave experiments to be performed in the nearest years. The role of dipole radio emission of fullerene-type dust nanostructures is shown to be small. The most precise estimates of the role of background radio sources with inverted spectra are given and these sources are shown to create no serious interference in experiments. The average spectral indices of the weakest sources of the NVSS and FIRST catalogs are estimated. The "saturation" data for all wavelengths allowed a constraint to be imposed on the Sunyaev-Zeldovich noise (the SZ noise) at all wavelengths, and made it possible to obtain independent estimates of the average sky temperature from sources, substantially weaker than those listed in the NVSS catalog. These estimates are inconsistent with the existence of powerful extragalactic synchrotron background associated with radio sources. Appreciable "quadrupole" anisotropy in is detected in the distribution of the spectral index of the synchrotron radiation of the Galaxy, and this anisotropy should be taken into account when estimating the polarization of the cosmic microwave background on small l. All the results are compared to the results obtained by foreign researchers in recent years.

  17. Background frequency of Bacillus species at the Canberra Airport: A 12 month study.

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    Gahan, Michelle E; Thomas, Rory; Rossi, Rebecca; Nelson, Michelle; Roffey, Paul; Richardson, Michelle M; McNevin, Dennis

    2015-12-01

    Anthrax, caused by Bacillus anthracis, is a naturally occurring disease in Australia. Whilst mainly limited to livestock in grazing regions of Victoria and New South Wales, movement of people, stock and vehicles means B. anthracis could be present outside this region. Of particular interest is the "background" prevalence of B. anthracis at transport hubs including airports. The aim of this study was to determine the background frequency of B. anthracis and the commonly used hoax agent Bacillus thuringiensis at the Canberra Airport over a 12 month period. Samples were collected daily for seven days each month from August 2011-July 2012 and analyzed using species specific real-time polymerase chain reaction. Fourteen samples (of a total of 575) were positive for the B. anthracis PL3 genomic marker, 24 for the cya (pXO1) plasmid marker and five for the capB (pXO2) plasmid marker. Whilst five samples were positive for both PL3 and cya, no samples were positive for all three markers hence there is no evidence to suggest the presence of pathogenic B. anthracis strains. B. anthracis targets were detected primarily in February 2012 and B. thuringiensis peaked in October and November 2011 and again in April and May 2012. This study provides a rapid method to screen for, and differentiate, Bacillus species. Armed with this information investigators will be able to discriminate a "threat" from "background" frequencies should the need arise.

  18. TALEN-Induced Translocations in Human Cells.

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    Piganeau, Marion; Renouf, Benjamin; Ghezraoui, Hind; Brunet, Erika

    2016-01-01

    Induction of chromosomal translocations in human cells is of a great interest to study tumorigenesis and genome instability. Here, we explain in detail a method to induce translocations using the transcription activator-like effector nucleases (TALENs). We describe how to detect translocation formation by PCR, calculate translocation frequency by 96-well PCR screen, and analyze breakpoint junctions. When inducing cancer translocations, it is also possible to detect the fusion gene by FISH analysis or western blot.

  19. Efficient induction of Wheat-agropyron cristatum 6P translocation lines and GISH detection.

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    Liqiang Song

    Full Text Available The narrow genetic background restricts wheat yield and quality improvement. The wild relatives of wheat are the huge gene pools for wheat improvement and can broaden its genetic basis. Production of wheat-alien translocation lines can transfer alien genes to wheat. So it is important to develop an efficient method to induce wheat-alien chromosome translocation. Agropyroncristatum (P genome carries many potential genes beneficial to disease resistance, stress tolerance and high yield. Chromosome 6P possesses the desirable genes exhibiting good agronomic traits, such as high grain number per spike, powdery mildew resistance and stress tolerance. In this study, the wheat-A. cristatum disomic addition was used as bridge material to produce wheat-A. cristatum translocation lines induced by (60Co-γirradiation. The results of genomic in situ hybridization showed that 216 plants contained alien chromosome translocation among 571 self-pollinated progenies. The frequency of translocation was 37.83%, much higher than previous reports. Moreover, various alien translocation types were identified. The analysis of M2 showed that 62.5% of intergeneric translocation lines grew normally without losing the translocated chromosomes. The paper reported a high efficient technical method for inducing alien translocation between wheat and Agropyroncristatum. Additionally, these translocation lines will be valuable for not only basic research on genetic balance, interaction and expression of different chromosome segments of wheat and alien species, but also wheat breeding programs to utilize superior agronomic traits and good compensation effect from alien chromosomes.

  20. Calibration of low-frequency radio telescopes using the galactic background radiation

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    Dulk, G. A.; Erickson, W. C.; Manning, R.; Bougeret, J.-L.

    2001-01-01

    We consider the calibration of flux densities of radio bursts from decametric to kilometric wavelengths using ground-based and space-based data. The method we derive is applicable to low-frequency radio telescopes where galactic background radiation is the principal contribution to system temperature. It can be particularly useful for telescopes of low angular resolution observing spectra of radio bursts from the Sun and the planets because absolute calibration of these telescopes is very difficult with conventional techniques. Here we apply the method to observations from about 7 to 47 MHz that were made on the ground with the Bruny Island Radio Spectrometer located in Tasmania, Australia, and those from about 20 kHz to 13.8 MHz were made with the radio experiment WAVES on the WIND spacecraft. The spectrum of the galactic background radiation from 30 MHz has been carefully measured with low-resolution telescopes, starting more than a decade ago. We use this known spectrum to calibrate both BIRS and WAVES on an absolute scale. The accuracy we achieve is about a factor of two, whereas the flux densities of solar and planetary radio sources vary by many orders of magnitude. Our method permits inter-calibration of ground-based and space-based observations, and allows corrections to be made for instrumental uncertainties on both radio experiments. In addition, on the ground, it allows the spectra to be corrected for ionospheric absorption and partial ground reflections. As an application we show the spectrum of a solar type III burst observed from 47 MHz to 20 kHz. Its flux density was largest, S~ 10-17 W m-2 Hz-1, at about 3 MHz, while at 60 kHz and at 47 MHz it was lower by a factor of about 300.

  1. Parkinson bradykinesia correlates with EEG background frequency and perceptual forward projection

    NARCIS (Netherlands)

    Beudel, Martijn; Roosma, E.; Manzanera, O. E. Martinez; van Laar, T.; Maurits, N. M.; de Jong, B. M.

    2015-01-01

    Background: To deal with processing-time in the nervous system, visuomotor control requires anticipation. An index for such anticipation is provided by the 'flash-lag illusion' in which moving objects are perceived ahead of static objects while actually being in the same place. We investigated the n

  2. Spatial frequency characteristics at image decision-point locations for observers with different radiological backgrounds in lung nodule detection

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    Pietrzyk, Mariusz W.; Manning, David J.; Dix, Alan; Donovan, Tim

    2009-02-01

    Aim: The goal of the study is to determine the spatial frequency characteristics at locations in the image of overt and covert observers' decisions and find out if there are any similarities in different observers' groups: the same radiological experience group or the same accuracy scored level. Background: The radiological task is described as a visual searching decision making procedure involving visual perception and cognitive processing. Humans perceive the world through a number of spatial frequency channels, each sensitive to visual information carried by different spatial frequency ranges and orientations. Recent studies have shown that particular physical properties of local and global image-based elements are correlated with the performance and the level of experience of human observers in breast cancer and lung nodule detections. Neurological findings in visual perception were an inspiration for wavelet applications in vision research because the methodology tries to mimic the brain processing algorithms. Methods: The wavelet approach to the set of postero-anterior chest radiographs analysis has been used to characterize perceptual preferences observers with different levels of experience in the radiological task. Psychophysical methodology has been applied to track eye movements over the image, where particular ROIs related to the observers' fixation clusters has been analysed in the spaces frame by Daubechies functions. Results: Significance differences have been found between the spatial frequency characteristics at the location of different decisions.

  3. IL-21 and probiotic therapy improve Th17 frequencies, microbial translocation, and microbiome in ARV-treated, SIV-infected macaques.

    Science.gov (United States)

    Ortiz, A M; Klase, Z A; DiNapoli, S R; Vujkovic-Cvijin, I; Carmack, K; Perkins, M R; Calantone, N; Vinton, C L; Riddick, N E; Gallagher, J; Klatt, N R; McCune, J M; Estes, J D; Paiardini, M; Brenchley, J M

    2016-03-01

    Increased mortality in antiretroviral (ARV)-treated, HIV-infected individuals has been attributed to persistent immune dysfunction, in part due to abnormalities at the gastrointestinal barrier. In particular, the poor reconstitution of gastrointestinal Th17 cells correlates with residual translocation of dysbiotic, immunostimulatory microflora across a compromised intestinal epithelial barrier. We have previously demonstrated that oral probiotics promote increased intestinal CD4(+) T-cell reconstitution during ARV treatment in a non-human primate model of HIV infection; however, essential mucosal T-cell subsets, such as Th17 cells, had limited recovery. Here, we sought to promote Th17 cell recovery by administering interleukin (IL)-21 to a limited number of ARV-treated, probiotic-supplemented, Simian Immunodeficiency Virus (SIV)-infected pigtailed macaques. We demonstrate that probiotic and IL-21 supplementation of ARVs are associated with enhanced polyfunctional Th17 expansion and reduced markers of microbial translocation and dysbiosis as compared with infected controls receiving ARVs alone. Importantly, treatment resulted in fewer morbidities compared with controls, and was independent of increased immune activation or loss of viral suppression. We propose that combining ARVs with therapeutics aimed at restoring intestinal stasis may significantly improve disease prognosis of ARV-treated, HIV-infected individuals.

  4. Long-distance translocations to create a second millerbird population and reduce extinction risk

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    Holly Freifeld,; Sheldon Plentovich,; Chris Farmer,; Charles Kohley,; Peter Luscomb,; Work, Thierry M.; Daniel Tsukayama,; George Wallace,; Mark MacDonald,; Sheila Conant,

    2016-01-01

    Translocation is a conservation tool used with increasing frequency to create additional populations of threatened species. In addition to following established general guidelines for translocations, detailed planning to account for unique circumstances and intensive post-release monitoring to document outcomes and guide management are essential components of these projects. Recent translocation of the critically endangered Nihoa millerbird (Acrocephalus familiaris kingi) provides an example of this planning and monitoring. The Nihoa millerbird is a passerine bird endemic to Nihoa Island in the remote Northwestern Hawaiian Islands. The closely related, ecologically similar Laysan millerbird (Acrocephalus familiaris familiaris) went extinct on Laysan Island in the early 20th century when the island was denuded by introduced rabbits. To reduce extinction risk, we translocated 50 adult Nihoa millerbirds more than 1000 km by sea to Laysan, which has recovered substantially in the past century and has ample habitat and a rich prey-base for millerbirds. Following five years of intensive background research and planning, including development of husbandry techniques, fundraising, and regulatory compliance, translocations occurred in 2011 and 2012. Of 11 females in each cohort, 8 (2011 cohort) and 11 (2012 cohort) produced at least one brood of fledglings during their first year on Laysan. At the conclusion of monitoring in September 2014, 37 of the translocated birds were known to survive, and the population was estimated at 164 birds. The reintroduction of millerbirds to Laysan represents a milestone in the island's ongoing restoration.

  5. Mode of ATM-dependent suppression of chromosome translocation

    Energy Technology Data Exchange (ETDEWEB)

    Yamauchi, Motohiro, E-mail: motoyama@nagasaki-u.ac.jp [Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Suzuki, Keiji; Oka, Yasuyoshi; Suzuki, Masatoshi; Kondo, Hisayoshi; Yamashita, Shunichi [Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan)

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer We addressed how ATM suppresses frequency of chromosome translocation. Black-Right-Pointing-Pointer We found ATM/p53-dependent G1 checkpoint suppresses translocation frequency. Black-Right-Pointing-Pointer We found ATM and DNA-PKcs function in a common pathway to suppress translocation. -- Abstract: It is well documented that deficiency in ataxia telangiectasia mutated (ATM) protein leads to elevated frequency of chromosome translocation, however, it remains poorly understood how ATM suppresses translocation frequency. In the present study, we addressed the mechanism of ATM-dependent suppression of translocation frequency. To know frequency of translocation events in a whole genome at once, we performed centromere/telomere FISH and scored dicentric chromosomes, because dicentric and translocation occur with equal frequency and by identical mechanism. By centromere/telomere FISH analysis, we confirmed that chemical inhibition or RNAi-mediated knockdown of ATM causes 2 to 2.5-fold increase in dicentric frequency at first mitosis after 2 Gy of gamma-irradiation in G0/G1. The FISH analysis revealed that ATM/p53-dependent G1 checkpoint suppresses dicentric frequency, since RNAi-mediated knockdown of p53 elevated dicentric frequency by 1.5-fold. We found ATM also suppresses dicentric occurrence independently of its checkpoint role, as ATM inhibitor showed additional effect on dicentric frequency in the context of p53 depletion and Chk1/2 inactivation. Epistasis analysis using chemical inhibitors revealed that ATM kinase functions in the same pathway that requires kinase activity of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to suppress dicentric frequency. From the results in the present study, we conclude that ATM minimizes translocation frequency through its commitment to G1 checkpoint and DNA double-strand break repair pathway that requires kinase activity of DNA-PKcs.

  6. 携带抗白粉病基因Pm21的小麦-簇毛麦小片段易位染色体在不同小麦背景中的传递率及遗传稳定性%Transmission and Genetic Stability of No-homoeologous Small Fragment Wheat-Haynaldia villosa Translocation Chromosomes with Pm21 in Various Cultivar Backgrounds of Common Wheat

    Institute of Scientific and Technical Information of China (English)

    王海燕; 肖进; 袁春霞; 徐涛; 于春艳; 孙昊杰; 陈佩度; 王秀娥

    2016-01-01

    the obtained F1s were analyzed by fluorescence in situ hybridization (FISH) of the PMC at MI. It was found that the translocation chromosomes formed rod bivalents with their corresponding wheat chromosomes. Test crosses showed that the translocation chromosomes T1AS×1AL-6VS and T4BS×4BL-6VS-4BL could be transmitted to their offspring. The transmission frequency of T1AS×1AL-6VS was higher through female gametes an average of 33.20%, ranging from 0.08% to 50.98%than through male gametes an average of 23.75%, ranging from 0.14%to 45.07%. Similarly, the transmission frequency of T4BS×4BL-6VS-4BL was higher through female gametes an average of 42.90%, ranging from 29.17%to 52.38%than through male gametes an average of 21.45%, ranging from 7.69%to 47.06%. These results show that the translocated chromosomes could be transmitted through male and female gametes, while genetic background has influences on the transmission rate, especially through male gametes.

  7. Increase in frequencies of circulating Th-17 cells correlates with microbial translocation, immune activation and exhaustion in HIV-1 infected patients with poor CD4 T-cell reconstitution.

    Science.gov (United States)

    Valiathan, Ranjini; Asthana, Deshratn

    2016-05-01

    We analyzed the association of circulating Th-17 cells (cTh-17) with immune activation (IA), immune exhaustion (IE) and regulatory T-cells (T-regs) in 20 human immunodeficiency virus-1 (HIV-1) infected patients with impaired restoration of CD4 T-cell counts despite prolonged suppression of plasma viremia (discordant) and compared it with 20 HIV-1 infected patients showing good immunologic and virologic responses (concordant) following highly active antiretroviral therapy (HAART). Discordant HIV-1 infected patients showed significantly higher frequencies of cTh-17 cells compared to concordant patients and healthy controls after PMA+Ionomicin stimulation. Discordant patients also showed higher CD4 T-cell immune activation (HLA-DR+CD38+) than concordant patients which directly correlated with microbial translocation. Additionally, CD4 T-cells of discordant patients showed higher frequencies of CD4 T-cells expressing multiple immune exhaustion markers (Tim3+PD-1+) which correlated with immune activation indicating that combined analysis of inhibitory molecules along with PD-1 might be a better predictor for immune exhaustion of CD4 T-cells. Increased cTh-17 cell frequency correlated inversely with CD4 T-cell percentages and absolute counts and directly with CD4 T-cell immune activation and T-reg frequencies. Persistent CD4 T-cell immune activation might favor differentiation of activated CD4 T-cells toward cTh-17 phenotype in discordant patients. Discordant patients had significantly lower baseline CD4 T-cell counts and higher viral load at the initiation of HAART and higher immune activation and immune exhaustion after being on HAART for long time indicating that these factors might be associated with an increase in cTh-17 cell frequency, thus, increasing the risk of disease progression despite virologic control.

  8. Effect of the genetic background on recombination frequency in the cn-vg region of the second chromosome of natural populations of Drosophila melanogaster.

    Science.gov (United States)

    Hofmanová, J

    1975-01-01

    Newly established test stocks made it possible to follow the effect of three different defined genetic backgrounds (first and third chromosomes) on recombination frequency in the cn-vg region of the second chromosomes isolated from four natural populations of Drosophila melanogaster. One background was composed of the chromosomes with inversions obtained from the stock (see article) and another two backgrounds were of the standard type consisting one-half of the original chromosomes from the natural population and one-half of the chromosomes of the stocks Oregon R or Samarkand. Using the analysis of variance significant differences in RF values were found between and within populations and especially between the different backgrounds. Some simple and double interactions between the above factors played a role. The highest RF values were obtained on the background [corrected] with inversions. The effect of the different genetic backgrounds [corrected] by the action of the genetic modifiers of RF. The different genetic backgrounds affected the variations in RF values in individual populations and the different populations reacted differentially to the changed genetic background. The design of the experiment permitted an estimation of the causal compoenents of variance and heritability of RF from the sib analysis. The additive component of variance was present in only two of the populations under test; the respective estimates of heritability were very low.

  9. Dynamics of forced biopolymer translocation

    CERN Document Server

    Lehtola, V V; Kaski, K; 10.1209/0295-5075/85/58006

    2009-01-01

    We present results from our simulations of biopolymer translocation in a solvent which explain the main experimental findings. The forced translocation can be described by simple force balance arguments for the relevant range of pore potentials in experiments and biological systems. Scaling of translocation time with polymer length varies with pore force and friction. Hydrodynamics affects this scaling and significantly reduces translocation times.

  10. The cytokinesis-blocked micronucleus assay: dose-response calibration curve, background frequency in the population and dose estimation.

    Science.gov (United States)

    Rastkhah, E; Zakeri, F; Ghoranneviss, M; Rajabpour, M R; Farshidpour, M R; Mianji, F; Bayat, M

    2016-03-01

    An in vitro study of the dose responses of human peripheral blood lymphocytes was conducted with the aim of creating calibrated dose-response curves for biodosimetry measuring up to 4 Gy (0.25-4 Gy) of gamma radiation. The cytokinesis-blocked micronucleus (CBMN) assay was employed to obtain the frequencies of micronuclei (MN) per binucleated cell in blood samples from 16 healthy donors (eight males and eight females) in two age ranges of 20-34 and 35-50 years. The data were used to construct the calibration curves for men and women in two age groups, separately. An increase in micronuclei yield with the dose in a linear-quadratic way was observed in all groups. To verify the applicability of the constructed calibration curve, MN yields were measured in peripheral blood lymphocytes of two real overexposed subjects and three irradiated samples with unknown dose, and the results were compared with dose values obtained from measuring dicentric chromosomes. The comparison of the results obtained by the two techniques indicated a good agreement between dose estimates. The average baseline frequency of MN for the 130 healthy non-exposed donors (77 men and 55 women, 20-60 years old divided into four age groups) ranged from 6 to 21 micronuclei per 1000 binucleated cells. Baseline MN frequencies were higher for women and for the older age group. The results presented in this study point out that the CBMN assay is a reliable, easier and valuable alternative method for biological dosimetry.

  11. Stochastic resonance during a polymer translocation process.

    Science.gov (United States)

    Mondal, Debasish; Muthukumar, M

    2016-04-14

    We have studied the occurrence of stochastic resonance when a flexible polymer chain undergoes a single-file translocation through a nano-pore separating two spherical cavities, under a time-periodic external driving force. The translocation of the chain is controlled by a free energy barrier determined by chain length, pore length, pore-polymer interaction, and confinement inside the donor and receiver cavities. The external driving force is characterized by a frequency and amplitude. By combining the Fokker-Planck formalism for polymer translocation and a two-state model for stochastic resonance, we have derived analytical formulas for criteria for emergence of stochastic resonance during polymer translocation. We show that no stochastic resonance is possible if the free energy barrier for polymer translocation is purely entropic in nature. The polymer chain exhibits stochastic resonance only in the presence of an energy threshold in terms of polymer-pore interactions. Once stochastic resonance is feasible, the chain entropy controls the optimal synchronization conditions significantly.

  12. Problem-elephant translocation: translocating the problem and the elephant?

    Directory of Open Access Journals (Sweden)

    Prithiviraj Fernando

    Full Text Available Human-elephant conflict (HEC threatens the survival of endangered Asian elephants (Elephas maximus. Translocating "problem-elephants" is an important HEC mitigation and elephant conservation strategy across elephant range, with hundreds translocated annually. In the first comprehensive assessment of elephant translocation, we monitored 16 translocations in Sri Lanka with GPS collars. All translocated elephants were released into national parks. Two were killed within the parks where they were released, while all the others left those parks. Translocated elephants showed variable responses: "homers" returned to the capture site, "wanderers" ranged widely, and "settlers" established home ranges in new areas soon after release. Translocation caused wider propagation and intensification of HEC, and increased elephant mortality. We conclude that translocation defeats both HEC mitigation and elephant conservation goals.

  13. Problem-elephant translocation: translocating the problem and the elephant?

    Science.gov (United States)

    Fernando, Prithiviraj; Leimgruber, Peter; Prasad, Tharaka; Pastorini, Jennifer

    2012-01-01

    Human-elephant conflict (HEC) threatens the survival of endangered Asian elephants (Elephas maximus). Translocating "problem-elephants" is an important HEC mitigation and elephant conservation strategy across elephant range, with hundreds translocated annually. In the first comprehensive assessment of elephant translocation, we monitored 16 translocations in Sri Lanka with GPS collars. All translocated elephants were released into national parks. Two were killed within the parks where they were released, while all the others left those parks. Translocated elephants showed variable responses: "homers" returned to the capture site, "wanderers" ranged widely, and "settlers" established home ranges in new areas soon after release. Translocation caused wider propagation and intensification of HEC, and increased elephant mortality. We conclude that translocation defeats both HEC mitigation and elephant conservation goals.

  14. Study of a dual frequency capacitively coupled rf discharge in the background of multi-component plasma and its validation by a simple analytical sheath model

    Science.gov (United States)

    Bhuyan, Heman; Saikia, Partha; Favre, Mario; Wyndham, Edmundo; Veloso, Felipe

    2016-10-01

    The behavior of a phase-locked dual frequency capacitively coupled rf discharges (2f-CCRF) in the background of multi-component plasma is experimentally studied by rf current-voltage measurements and optical emission spectroscopy (OES). The multi-component plasma is produced by adding hydrogen to the argon CCRF discharge. Variation of experimental parameters, like working pressure, low frequency (LF) and high frequency (HF) rf power indicate significant changes in the electron density and temperature as well as the DC self-bias developed on the power electrode. It is observed that the electron density decreases as the percentage of hydrogen increases in the argon plasma while the electron temperature follows opposite trend. An analytical sheath model for the 2f-CCRF discharge in the background of multi-component plasma is developed and its prediction on the observed variation of DC self-bias is well agreed with the experimental observations. Authors acknowledge Proyecto Puente No P1611 and FONDECYT 3160179.

  15. Mode of ATM-dependent suppression of chromosome translocation.

    Science.gov (United States)

    Yamauchi, Motohiro; Suzuki, Keiji; Oka, Yasuyoshi; Suzuki, Masatoshi; Kondo, Hisayoshi; Yamashita, Shunichi

    2011-12-09

    It is well documented that deficiency in ataxia telangiectasia mutated (ATM) protein leads to elevated frequency of chromosome translocation, however, it remains poorly understood how ATM suppresses translocation frequency. In the present study, we addressed the mechanism of ATM-dependent suppression of translocation frequency. To know frequency of translocation events in a whole genome at once, we performed centromere/telomere FISH and scored dicentric chromosomes, because dicentric and translocation occur with equal frequency and by identical mechanism. By centromere/telomere FISH analysis, we confirmed that chemical inhibition or RNAi-mediated knockdown of ATM causes 2 to 2.5-fold increase in dicentric frequency at first mitosis after 2 Gy of gamma-irradiation in G0/G1. The FISH analysis revealed that ATM/p53-dependent G1 checkpoint suppresses dicentric frequency, since RNAi-mediated knockdown of p53 elevated dicentric frequency by 1.5-fold. We found ATM also suppresses dicentric occurrence independently of its checkpoint role, as ATM inhibitor showed additional effect on dicentric frequency in the context of p53 depletion and Chk1/2 inactivation. Epistasis analysis using chemical inhibitors revealed that ATM kinase functions in the same pathway that requires kinase activity of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to suppress dicentric frequency. From the results in the present study, we conclude that ATM minimizes translocation frequency through its commitment to G1 checkpoint and DNA double-strand break repair pathway that requires kinase activity of DNA-PKcs.

  16. Inducement of chromosome translocation with small alien segments by irradiating mature female gametes of the whole arm translocation line

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Haynaldia villosa Schur. (syn. Dasypyrum villosum Candargy, 2n=14, VV) has been proved to be an important genetic resource for wheat improvement. The development of translocation with small alien chromosome segments, especially interstitial translocation, will be helpful for better utilization of its useful genes. Up to now, most of the reported Triticum aestivum – H. villosa translocation lines are involved in a whole arm or large alien fragments. In this paper, we report a highly efficient approach for the creation of small chromosome segment translocation lines. Before flowering, the female gametes of wheat-H. villosa 6VS/6AL translocation line were irradiated by 60CO-γ ray at 160 Rad/M dosage rate and three dosages (1600, 1920, 2240 Rad). Anthers were removed from the irradiated florets on the same day and the florets were pollinated with normal fresh pollens of T. aestivum cv. Chinese Spring after 2-3 days. Genomic in situ hybridization (GISH) at mitosis metaphase of root-tip cell of M1 plants was used to detect the chromosome structural changes involving 6VS of H. villosa. Among the 534 M1 plants screened, 97 plants contained small segment chromosome structural changes of 6VS, including 80 interstitial translocation chromosomes, 57 terminal translocation chromosomes and 55 deletion chromosomes. For the 2240 Rad dosage treatment, the inducement frequencies of interstitial translo-cation, terminal translocation and deletion were 21.02%, 14.01%, and 14.65%, respectively, which were much higher than those previously reported. The M2 seeds were obtained by backcrossing of 74 M1 plants involving 146 chromosomes structural changes of 6VS, and it was found that the structural aberrations in the M1 plants could be transmitted to their progenies. Irradiating mature female gametes of whole arm translocation is a new and highly efficient approach for creation of small segment chromosome struc-tural changes, especially for interstitial translocations.

  17. [Changes in the chromatin structure of lymphoid cells under the influence of low-intensity extremely high-frequency electromagnetic radiation against the background of inflammatory process].

    Science.gov (United States)

    Gapeev, A B; Romanova, N A; Chemeris, N K

    2011-01-01

    Using the alkaline single cell gel electrophoresis technique (comet assay), changes in chromatin structure of peripheral blood leukocytes and peritoneal neutrophils have been studied in mice exposed to low-intensity extremely high-frequency electromagnetic radiation (42.2 GHz, 0.1 mW/cm2, 20 min at 1 h after induction of inflammation) against the background of the systemic inflammatory process. It was revealed that the exposure of mice with the developing inflammation leads to a pronounced decrease in the level of DNA damage to peripheral blood leukocytes and peritoneal neutrophils. It is supposed that the changes in the chromatin structure of lymphoid cells have a genoprotective character in the inflammatory process and can underlie the mechanisms of realization of antiinflammatory effects of the electromagnetic radiation.

  18. Mechanisms underlying stage-1 TRPL channel translocation in Drosophila photoreceptors.

    Directory of Open Access Journals (Sweden)

    Minh-Ha Lieu

    Full Text Available BACKGROUND: TRP channels function as key mediators of sensory transduction and other cellular signaling pathways. In Drosophila, TRP and TRPL are the light-activated channels in photoreceptors. While TRP is statically localized in the signaling compartment of the cell (the rhabdomere, TRPL localization is regulated by light. TRPL channels translocate out of the rhabdomere in two distinct stages, returning to the rhabdomere with dark-incubation. Translocation of TRPL channels regulates their availability, and thereby the gain of the signal. Little, however, is known about the mechanisms underlying this trafficking of TRPL channels. METHODOLOGY/PRINCIPAL FINDINGS: We first examine the involvement of de novo protein synthesis in TRPL translocation. We feed flies cycloheximide, verify inhibition of protein synthesis, and test for TRPL translocation in photoreceptors. We find that protein synthesis is not involved in either stage of TRPL translocation out of the rhabdomere, but that re-localization to the rhabdomere from stage-1, but not stage-2, depends on protein synthesis. We also characterize an ex vivo eye preparation that is amenable to biochemical and genetic manipulation. We use this preparation to examine mechanisms of stage-1 TRPL translocation. We find that stage-1 translocation is: induced with ATP depletion, unaltered with perturbation of the actin cytoskeleton or inhibition of endocytosis, and slowed with increased membrane sterol content. CONCLUSIONS/SIGNIFICANCE: Our results indicate that translocation of TRPL out of the rhabdomere is likely due to protein transport, and not degradation/re-synthesis. Re-localization from each stage to the rhabdomere likely involves different strategies. Since TRPL channels can translocate to stage-1 in the absence of ATP, with no major requirement of the cytoskeleton, we suggest that stage-1 translocation involves simple diffusion through the apical membrane, which may be regulated by release of a

  19. Inducement of chromosome translocation with small alien segments by irradiating mature female gametes of the whole arm translocation line

    Institute of Scientific and Technical Information of China (English)

    CHEN ShengWei; CHEN PeiDu; WANG XiuE

    2008-01-01

    Haynaldia villosa Schur. (syn. Dasypyrum villosum Candargy, 2n=14, VV) has been proved to be an Important genetic resource for wheat improvement. The development of translocation with small alien chromosome segments, especially interstitial translocation, will be helpful for better utilization of its useful genes. Up to now, most of the reported Triticum aestivum - H. villosa translocation lines are involved in a whole arm or large alien fragments. In this paper, we report a highly efficient approach for the creation of small chromosome segment translocation lines. Before flowering, the female gametes of wheat-H, villosa 6VS/6AL trsnslocation line were irradiated by 60Co-γ ray at 160 Rad/M dosage rate and three dosages (1600, 1920, 2240 Rad). Anthers were removed from the irradiated florets on the same day and the florets were pollinated with normal fresh pollens of T. aestivum cv. Chinese Spring after 2-3 days. Genomic in situ hybridization (GISH) at mitosis metaphase of root-tip cell of M1 plants was used to detect the chromosome structural changes involving 6VS of H. villosa. Among the 534 M1 plants screened, 97 plants contained small segment chromosome structural changes of 6VS, including 80 interstitial translocation chromosomes, 57 terminal translocation chromosomes and 55 deletion chromosomes. For the 2240 Rad dosage treatment, the inducement frequencies of interstitial translocation, terminal translocation and deletion were 21.02%, 14.01%, and 14.65%, respectively, which were much higher than those previously reported. The M2 seeds were obtained by bsckcrossing of 74 M1 plants involving 146 chromosomes structural changes of 6VS, and it was found that the structural aberrations in the M1 plants could be transmitted to their progenies. Irradiating mature female gametes of whole arm translocation is a new and highly efficient approach for creation of small segment chromosome structural changes, especially for interstitial translocations.

  20. Twin-Arginine Protein Translocation

    NARCIS (Netherlands)

    Goosens, Vivianne J; van Dijl, Jan Maarten

    2016-01-01

    Twin-arginine protein translocation systems (Tat) translocate fully folded and co-factor-containing proteins across biological membranes. In this review, we focus on the Tat pathway of Gram-positive bacteria. The minimal Tat pathway is composed of two components, namely a TatA and TatC pair, which a

  1. Multiscale control of summertime persistent heavy precipitation events over South China in association with synoptic, intraseasonal, and low-frequency background

    Science.gov (United States)

    Li, Richard C. Y.; Zhou, Wen

    2015-08-01

    This study examines persistent and short-lived heavy precipitation events (PHPEs and SHPEs, respectively) in South China during summer (July-September) 1975-2009 in association with large-scale circulation and moisture processes at different timescales. Compared to SHPEs, PHPEs are characterized by long-lasting enhanced convection and cyclonic moisture circulation as well as strengthened moisture convergence over South China. Examination of environmental variables at different timescales suggests that intraseasonal and synoptic components play a deterministic role in regulating the overall changes in convection and moisture convergence, while the low-frequency background state plays only a marginal role. Further analysis of the moisture divergence terms also reveals that the overall changes in moisture divergence during PHPEs and SHPEs stem primarily from variations in the intraseasonal and synoptic wind fields rather than in the humidity fields. Overall, it is found that the location and strength of the intraseasonal oscillation (ISO) and the synoptic disturbances play a decisive role in controlling the severity and duration of rainfall events over South China. The synchronization and persistence of the enhanced convection and moisture circulation of the ISO and synoptic disturbances jointly contribute to prolonged heavy precipitation over South China, while the weakening and asynchrony of the associated convection and moisture circulation at different timescales result in rainfall events of weaker intensity and shorter duration.

  2. Genomic Comparison of Translocating and Non-Translocating Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Nathan L Bachmann

    Full Text Available Translocation of E. coli across the gut epithelium can result in fatal sepsis in post-surgical patients. In vitro and in vivo experiments have identified the existence of a novel pathotype of translocating E. coli (TEC that employs an unknown mechanism for translocating across epithelial cells to the mesenteric lymph nodes and the blood stream in both humans and animal models. In this study the genomes of four TEC strains isolated from the mesenteric lymph nodes of a fatal case of hospitalised patient (HMLN-1, blood of pigs after experimental shock (PC-1 and after non-lethal haemorrhage in rats (KIC-1 and KIC-2 were sequenced in order to identify the genes associated with their adhesion and/or translocation. To facilitate the comparison, the genomes of a non-adhering, non-translocating E. coli (46-4 and adhering but non-translocating E. coli (73-89 were also sequenced and compared. Whole genome comparison revealed that three (HMLN-1, PC-1 and KIC-2 of the four TEC strains carried a genomic island that encodes a Type 6 Secretion System that may contribute to adhesion of the bacteria to gut epithelial cells. The human TEC strain HMLN-1 also carried the invasion ibeA gene, which was absent in the animal TEC strains and is likely to be associated with host-specific translocation. Phylogenetic analysis revealed that the four TEC strains were distributed amongst three distinct E. coli phylogroups, which was supported by the presence of phylogroup specific fimbriae gene clusters. The genomic comparison has identified potential genes that can be targeted with knock-out experiments to further characterise the mechanisms of E. coli translocation.

  3. Electochemical detection of chromosome translocation

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Dimaki, Maria; Silahtaroglu, Asli;

    2014-01-01

    Cytogenetics is a study of the cell structure with a main focus on chromosomes content and their structure. Chromosome abnormalities, such as translocations may cause various genetic disorders and heametological malignancies. Chromosome translocations are structural rearrangements of two...... chromosomes that results in formation of derivative chromosomes with a mixed DNA sequence. The method currently used for their detection is Fluorescent In Situ Hybridization, which requires a use of expensive, fluorescently labeled probes that target the derivative chromosomes. We present here a double...... hybridization approach developed for label-free detection of the chromosome translocations. For specific translocation detection it is necessary to determine that the two DNA sequences forming a derivative chromosome are connected, which is achieved by two subsequent hybridization steps. The electrochemical...

  4. Macular pigment and fixation after macular translocation surgery

    NARCIS (Netherlands)

    Reinhard, Jens; Kanis, Martijn J.; Berendschot, Tos T. J. M.; Schoen, Christiane; Gelisken, Faik; Trauzettel-Klosinski, Susanne; Bartz-Schmidt, Karl U.; Zrenner, Eberhart

    2010-01-01

    Background After full macular translocation (MT) surgery with 3608 retinotomy, the fovea is rarely identifiable. Our aim was to verify the position of the fovea, to determine how patients fixate after MT and to examine distribution and optical density of macular pigment ( MP). Methods 9 patients aft

  5. Bear River Migratory Bird Refuge trumperter swan translocation project : Issues/action items

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Background information and current issues regarding the trumpeter swan translocation project at Bear River Migratory Bird Refuge. Major issues include harvesting of...

  6. Chromosome 14 translocations in non-Burkitt lymphomas

    Energy Technology Data Exchange (ETDEWEB)

    Fukuhara, S.; Rowley, J.D.

    1978-01-01

    Chromosome studies were performed on malignant cells obtained from 27 patients with non-Burkitt lymphomas. A marker chromosome affecting the long arm of No. 14 (14q+) was the single most frequent abnormality and was noted in 17 of these patients. The frequency of the 14q+ marker varied with the type of lymphoma. For patients with malignant lymphoma, histiocytic, the frequency was 5 or 8; for mixed-cell type, 1 of 3; for poorly differentiated lymphocytic, 8 of 8; for well-differentiated lymphocytic, 0.3; for lymphoblastic, 0 of 1; for Hodgkin's disease, 2 of 3; and for mycosis fungoides, 1 of 1. The donor chromosome involved in the 14q translocation was identified in 12 cases; certain chromosomes appeared to be affected more frequently than others. Although the break point was band 14q32 in most cases, the exact location of the receptor site on 14q was not always consistent. The distal part of 14q24 was also involved as a receptor site in at least one translocation. These findings suggest that, in some types of lymphoid malignancy, cells with a 14q translocation have a proliferative advantage over cells with other chromosome rearrangements. The presence of the 14q translocation may be important in the future for the distinction among morphologically different, but functionally comparable, subgroups of lymphoid malignancies.

  7. Three-dimensional genome architecture influences partner selection for chromosomal translocations in human disease.

    Directory of Open Access Journals (Sweden)

    Jesse M Engreitz

    Full Text Available Chromosomal translocations are frequent features of cancer genomes that contribute to disease progression. These rearrangements result from formation and illegitimate repair of DNA double-strand breaks (DSBs, a process that requires spatial colocalization of chromosomal breakpoints. The "contact first" hypothesis suggests that translocation partners colocalize in the nuclei of normal cells, prior to rearrangement. It is unclear, however, the extent to which spatial interactions based on three-dimensional genome architecture contribute to chromosomal rearrangements in human disease. Here we intersect Hi-C maps of three-dimensional chromosome conformation with collections of 1,533 chromosomal translocations from cancer and germline genomes. We show that many translocation-prone pairs of regions genome-wide, including the cancer translocation partners BCR-ABL and MYC-IGH, display elevated Hi-C contact frequencies in normal human cells. Considering tissue specificity, we find that translocation breakpoints reported in human hematologic malignancies have higher Hi-C contact frequencies in lymphoid cells than those reported in sarcomas and epithelial tumors. However, translocations from multiple tissue types show significant correlation with Hi-C contact frequencies, suggesting that both tissue-specific and universal features of chromatin structure contribute to chromosomal alterations. Our results demonstrate that three-dimensional genome architecture shapes the landscape of rearrangements directly observed in human disease and establish Hi-C as a key method for dissecting these effects.

  8. Association of markers of bacterial translocation with immune activation in decompensated cirrhosis

    DEFF Research Database (Denmark)

    Mortensen, Christian; Jensen, Jørgen Skov; Hobolth, Lise;

    2014-01-01

    BACKGROUND: Bacterial translocation (BT) may cause infections, in particular, spontaneous bacterial peritonitis (SBP). In the absence of overt infection, BT may further stimulate the immune system and contribute to haemodynamic alterations and complications. Bacterial DNA (bDNA) is claimed...... or positive cultures, we found a high frequency of bDNA but low concordance of bDNA between blood and ascites. Markers of inflammation were not significantly different between blood bDNA-positive (22%), ascites bDNA-positive (52%), and bDNA-negative patients. The 16S rDNA PCR failed to show bDNA in two out...... of six samples with SBP. Sequencing of positive samples did not determine the source of bDNA. CONCLUSION: bDNA as assessed by this PCR method was largely unrelated to markers of inflammation and does not seem to be of clinical value in the diagnosis of SBP. According to our results, b...

  9. DNA Translocation through Graphene Nanopores

    CERN Document Server

    Schneider, Grégory F; Calado, Victor E; Pandraud, Grégory; Zandbergen, Henny W; Vandersypen, Lieven M K; Dekker, Cees

    2010-01-01

    Nanopores -- nanosized holes that can transport ions and molecules -- are very promising devices for genomic screening, in particular DNA sequencing. Both solid-state and biological pores suffer from the drawback, however, that the channel constituting the pore is long, viz. 10-100 times the distance between two bases in a DNA molecule (0.5 nm for single-stranded DNA). Here, we demonstrate that it is possible to realize and use ultrathin nanopores fabricated in graphene monolayers for single-molecule DNA translocation. The pores are obtained by placing a graphene flake over a microsize hole in a silicon nitride membrane and drilling a nanosize hole in the graphene using an electron beam. As individual DNA molecules translocate through the pore, characteristic temporary conductance changes are observed in the ionic current through the nanopore, setting the stage for future genomic screening.

  10. Chromosome 4q;10q translocations; Comparison with different ethnic populations and FSHD patients

    Directory of Open Access Journals (Sweden)

    Zhang Cheng

    2002-08-01

    Full Text Available Abstract Background Facioscapulohumeral muscular dystrophy (FSHD is an autosomal dominant disorder characterized by the weakness of facial, shoulder-girdle and upper arm muscles. Most patients with FSHD have fewer numbers of tandem repeated 3.3-kb KpnI units on chromosome 4q35. Chromosome 10q26 contains highly homologous KpnI repeats, and inter-chromosomal translocation has been reported. Methods To clarify the influence on the deletion of the repeats, we surveyed three different ethnic populations and FSHD patients using the BglII/BlnI dosage test. Results The frequency of translocation in 153 Japanese, 124 Korean, 114 Chinese healthy individuals and 56 Japanese 4q35-FSHD patients were 27.5%, 29.8%, 19.3%, and 32.1%, respectively. The ratio of '4 on 10' (trisomy and quatrosomy of chromosome 4 was higher than that of '10 on 4' (nullsomy and monosomy of chromosome 4 in all populations. Conclusions The inter-chromosomal exchange was frequently observed in all four populations we examined, and no significant difference was observed between healthy and diseased groups.

  11. Meiotic segregation and interchromosomal effect in the sperm of a double translocation carrier: a case report

    Directory of Open Access Journals (Sweden)

    Laureano Lucimar AF

    2009-12-01

    Full Text Available Abstract Background Infertility is a natural mechanism of selection intended to prevent the delivery of a child with malformations or mental retardation. Male infertility is closely related to chromosomal abnormalities. This study was focused on the analysis of meiotic segregation involving a Robertsonian translocation, 45,XY,der(13;13 [56]/45,XY,der(13;14 [44] and the evaluation of possible interchromosomal effects. Results Hybridisation with LSI 13q14 and subtelomere 14q probes and WCP13 SpectrumGreen and WCP14 SpectrumOrange probes showed a high proportion of unbalanced gametes, corresponding to 71.2% of the spermatozoa. The disomic frequencies of the sexual chromosomes and chromosome 18 of the patient were higher (5.28% and 2.55%, respectively than those of the control (0.6% and 0.59%, respectively. Conclusion Meiotic segregation studies in sperm are an important tool for genetic counselling of chromosomal aberrations, allowing for a prediction of the risks and consequent implications for the reproductive life. The patient with this rare translocation exhibited meiotic segregation fidelity, and a high rate of unbalanced gametes with disomic spermatozoa.

  12. Variations in voice level and fundamental frequency with changing background noise level and talker-to-listener distance while wearing hearing protectors: A pilot study

    DEFF Research Database (Denmark)

    Bouserhal, Rachel E.; MacDonald, Ewen; Falk, Tiago H.;

    2016-01-01

    concern for people wearing hearing protection devices (HPD). Although practical, radio communication is cumbersome, as it does not distinguish designated receivers. A smarter radio communication protocol must be developed to alleviate this problem. Thus, it is necessary to model speech production in noise...... while wearing HPDs. Such a model opens the door to radio communication systems that distinguish receivers and offer more efficient communication between persons wearing HPDs. Design: This paper presents the results of a pilot study aimed to investigate the effects of occluding the ear on changes...... in voice level and fundamental frequency in noise and with varying talker-to-listener distance. Study sample: Twelve participants with a mean age of 28 participated in this study. Results: Compared to existing data, results show a trend similar to the open ear condition with the exception of the occluded...

  13. Observations of 1ES 1101-232 with H.E.S.S. and at lower frequencies: A hard spectrum blazar and constraints on the extragalactic background light

    Science.gov (United States)

    Pühlhofer, Gerd; Benbow, Wystan; Costamante, Luigi; Sol, Helene; Boisson, Catherine; Emmanoulopoulos, Dimitrios; Wagner, Stefan; Horns, Dieter; Giebels, Berrie

    VHE observations of the distant (z=0.186) blazar 1ES 1101-232 with H.E.S.S. are used to constrain the extragalactic background light (EBL) in the optical to near infrared band. As the EBL traces the galaxy formation history of the universe, galaxy evolution models can therefore be tested with the data. In order to measure the EBL absorption effect on a blazar spectrum, we assume that usual constraints on the hardness of the intrinsic blazar spectrum are not violated. We present an update of the VHE spectrum obtained with H.E.S.S. and the multifrequency data that were taken simultaneously with the H.E.S.S. measurements. The data verify that the broadband characteristics of 1ES 1101-232 are similar to those of other, more nearby blazars, and strengthen the assumptions that were used to derive the EBL upper limit.

  14. Model Evaluation and Projection on the Linkage between Hadley Circulation and Atmospheric Background Related to the Tropical Cyclone Frequency over the Western North Pacific

    Institute of Scientific and Technical Information of China (English)

    ZHOU Bo-Tao

    2012-01-01

    The performance of climate models in simulating the linkage of the spring Hadley circulation (HC) to the vertical zonal wind shear and atmospheric divergence in the lower and upper troposphere, which are related to the tropical cyclone frequency over the western North Pacific (WNPTCF) during June–September (JJAS), is evaluated on the basis of the 20th century climate simulations (20C3M). It is found that four models can simulta-neously reproduce the pattern revealed in the observation, with the spring HC in the Northern Hemisphere being positively correlated to the vertical zonal wind shear in the major tropical cyclone (TC) genesis region and negatively (positively) correlated to the atmospheric diver- gence in the upper (lower) troposphere over the western North Pacific (WNP) in the following JJAS. These four models are further used to project their relationship in the late 21st century under the A1B scenario. The results show that the association of spring HC with the vertical zonal wind shear and the upper-and lower-tropospheric divergence over the WNP will weaken in the late 21st century, thereby resulting in a weak relationship between the spring HC and the JJAS WNPTCF.

  15. X-ray-induced translocations in marmoset (Callithrix jacchus) stem-cell spermatogonia

    Energy Technology Data Exchange (ETDEWEB)

    Buul, P.P.W. van (Rijksuniversiteit Leiden (Netherlands). Lab. voor Stralengenetica en Chemische Mutagenese)

    1984-11-01

    The induction of reciprocal translocations in spermatogonial stem cells of marmosets (Callithrix jacchus) was studied after irradiation with different doses of X-rays (50, 100 and 200 rad) via spermatocyte analysis many cell generations later. The obtained results show a dose-effect relationship with clear saturation effects at 200 rad. The recorded frequencies of translocations were much lower than those reported for closely related marmosets (Saguinus fuscicollis and Saguinus oedipus). Possible reasons for this difference are discussed.

  16. Creating cancer translocations in human cells using Cas9 DSBs and nCas9 paired nicks.

    Science.gov (United States)

    Renouf, Benjamin; Piganeau, Marion; Ghezraoui, Hind; Jasin, Maria; Brunet, Erika

    2014-01-01

    Recurrent chromosomal translocations are found in numerous tumor types, often leading to the formation and expression of fusion genes with oncogenic potential. Creating chromosomal translocations at the relevant endogenous loci, rather than ectopically expressing the fusion genes, opens new possibilities for better characterizing molecular mechanisms driving tumor formation. In this chapter, we describe methods to create cancer translocations in human cells. DSBs or paired nicks generated by either wild-type Cas9 or the Cas9 nickase, respectively, are used to induce translocations at the relevant loci. Using different PCR-based methods, we also explain how to quantify translocation frequency and to analyze breakpoint junctions in the cells of interest. In addition, PCR detection of translocations is used as a very sensitive method to detect off-target effects, which has general utility.

  17. Background Material

    DEFF Research Database (Denmark)

    Zandersen, Marianne; Hyytiäinen, Kari; Saraiva, Sofia;

    2016-01-01

    This document serves as a background material to the BONUS Pilot Scenario Workshop, which aims to develop harmonised regional storylines of socio-ecological futures in the Baltic Sea region in a collaborative effort together with other BONUS projects and stakeholders....

  18. DNA ligase III promotes alternative nonhomologous end-joining during chromosomal translocation formation.

    Science.gov (United States)

    Simsek, Deniz; Brunet, Erika; Wong, Sunnie Yan-Wai; Katyal, Sachin; Gao, Yankun; McKinnon, Peter J; Lou, Jacqueline; Zhang, Lei; Li, James; Rebar, Edward J; Gregory, Philip D; Holmes, Michael C; Jasin, Maria

    2011-06-01

    Nonhomologous end-joining (NHEJ) is the primary DNA repair pathway thought to underlie chromosomal translocations and other genomic rearrangements in somatic cells. The canonical NHEJ pathway, including DNA ligase IV (Lig4), suppresses genomic instability and chromosomal translocations, leading to the notion that a poorly defined, alternative NHEJ (alt-NHEJ) pathway generates these rearrangements. Here, we investigate the DNA ligase requirement of chromosomal translocation formation in mouse cells. Mammals have two other DNA ligases, Lig1 and Lig3, in addition to Lig4. As deletion of Lig3 results in cellular lethality due to its requirement in mitochondria, we used recently developed cell lines deficient in nuclear Lig3 but rescued for mitochondrial DNA ligase activity. Further, zinc finger endonucleases were used to generate DNA breaks at endogenous loci to induce translocations. Unlike with Lig4 deficiency, which causes an increase in translocation frequency, translocations are reduced in frequency in the absence of Lig3. Residual translocations in Lig3-deficient cells do not show a bias toward use of pre-existing microhomology at the breakpoint junctions, unlike either wild-type or Lig4-deficient cells, consistent with the notion that alt-NHEJ is impaired with Lig3 loss. By contrast, Lig1 depletion in otherwise wild-type cells does not reduce translocations or affect microhomology use. However, translocations are further reduced in Lig3-deficient cells upon Lig1 knockdown, suggesting the existence of two alt-NHEJ pathways, one that is biased toward microhomology use and requires Lig3 and a back-up pathway which does not depend on microhomology and utilizes Lig1.

  19. DNA ligase III promotes alternative nonhomologous end-joining during chromosomal translocation formation.

    Directory of Open Access Journals (Sweden)

    Deniz Simsek

    2011-06-01

    Full Text Available Nonhomologous end-joining (NHEJ is the primary DNA repair pathway thought to underlie chromosomal translocations and other genomic rearrangements in somatic cells. The canonical NHEJ pathway, including DNA ligase IV (Lig4, suppresses genomic instability and chromosomal translocations, leading to the notion that a poorly defined, alternative NHEJ (alt-NHEJ pathway generates these rearrangements. Here, we investigate the DNA ligase requirement of chromosomal translocation formation in mouse cells. Mammals have two other DNA ligases, Lig1 and Lig3, in addition to Lig4. As deletion of Lig3 results in cellular lethality due to its requirement in mitochondria, we used recently developed cell lines deficient in nuclear Lig3 but rescued for mitochondrial DNA ligase activity. Further, zinc finger endonucleases were used to generate DNA breaks at endogenous loci to induce translocations. Unlike with Lig4 deficiency, which causes an increase in translocation frequency, translocations are reduced in frequency in the absence of Lig3. Residual translocations in Lig3-deficient cells do not show a bias toward use of pre-existing microhomology at the breakpoint junctions, unlike either wild-type or Lig4-deficient cells, consistent with the notion that alt-NHEJ is impaired with Lig3 loss. By contrast, Lig1 depletion in otherwise wild-type cells does not reduce translocations or affect microhomology use. However, translocations are further reduced in Lig3-deficient cells upon Lig1 knockdown, suggesting the existence of two alt-NHEJ pathways, one that is biased toward microhomology use and requires Lig3 and a back-up pathway which does not depend on microhomology and utilizes Lig1.

  20. Campylobacter jejuni induces transcellular translocation of commensal bacteria via lipid rafts

    Directory of Open Access Journals (Sweden)

    Kalischuk Lisa D

    2009-02-01

    Full Text Available Abstract Background Campylobacter enteritis represents a risk factor for the development of inflammatory bowel disease (IBD via unknown mechanisms. As IBD patients exhibit inflammatory responses to their commensal intestinal microflora, factors that induce translocation of commensal bacteria across the intestinal epithelium may contribute to IBD pathogenesis. This study sought to determine whether Campylobacter induces translocation of non-invasive intestinal bacteria, and characterize underlying mechanisms. Methods Mice were infected with C. jejuni and translocation of intestinal bacteria was assessed by quantitative bacterial culture of mesenteric lymph nodes (MLNs, liver, and spleen. To examine mechanisms of Campylobacter-induced bacterial translocation, transwell-grown T84 monolayers were inoculated with non-invasive Escherichia coli HB101 ± wild-type Campylobacter or invasion-defective mutants, and bacterial internalization and translocation were measured. Epithelial permeability was assessed by measuring flux of a 3 kDa dextran probe. The role of lipid rafts was assessed by cholesterol depletion and caveolin co-localization. Results C. jejuni 81–176 induced translocation of commensal intestinal bacteria to the MLNs, liver, and spleen of infected mice. In T84 monolayers, Campylobacter-induced internalization and translocation of E. coli occurred via a transcellular pathway, without increasing epithelial permeability, and was blocked by depletion of epithelial plasma membrane cholesterol. Invasion-defective mutants and Campylobacter-conditioned cell culture medium also induced E. coli translocation, indicating that C. jejuni does not directly 'shuttle' bacteria into enterocytes. In C. jejuni-treated monolayers, translocating E. coli associated with lipid rafts, and this phenomenon was blocked by cholesterol depletion. Conclusion Campylobacter, regardless of its own invasiveness, promotes the translocation of non-invasive bacteria across

  1. Translocations affecting human immunoglobulin heavy chain locus

    Directory of Open Access Journals (Sweden)

    Sklyar I. V.

    2014-03-01

    Full Text Available Translocations involving human immunoglobulin heavy chain (IGH locus are implicated in different leukaemias and lymphomas, including multiple myeloma, mantle cell lymphoma, Burkitt’s lymphoma and diffuse large B cell lymphoma. We have analysed published data and identified eleven breakpoint cluster regions (bcr related to these cancers within the IgH locus. These ~1 kbp bcrs are specific for one or several types of blood cancer. Our findings could help devise PCR-based assays to detect cancer-related translocations, to identify the mechanisms of translocations and to help in the research of potential translocation partners of the immunoglobulin locus at different stages of B-cell differentiation.

  2. Haloarchaeal Protein Translocation via the Twin Arginine Translocation Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Pohlschroder Mechthild

    2009-02-03

    Protein transport across hydrophobic membranes that partition cellular compartments is essential in all cells. The twin arginine translocation (Tat) pathway transports proteins across the prokaryotic cytoplasmic membranes. Distinct from the universally conserved Sec pathway, which secretes unfolded proteins, the Tat machinery is unique in that it secretes proteins in a folded conformation, making it an attractive pathway for the transport and secretion of heterologously expressed proteins that are Sec-incompatible. During the past 7 years, the DOE-supported project has focused on the characterization of the diversity of bacterial and archaeal Tat substrates as well as on the characterization of the Tat pathway of a model archaeon, Haloferax volcanii, a member of the haloarchaea. We have demonstrated that H. volcanii uses this pathway to transport most of its secretome.

  3. Gold nanoparticle translocation dynamics and electrical detection of single particle diffusion using solid-state nanopores.

    Science.gov (United States)

    Goyal, Gaurav; Freedman, Kevin J; Kim, Min Jun

    2013-09-01

    This paper describes the use of gold nanoparticles to study particle translocation dynamics through silicon nitride solid-state nanopores. Gold nanoparticles were dispersed in 20 mM KCl solution containing nonionic surfactant Triton X-100 and their translocation was studied at different applied voltages. The use of low electrolyte concentration resulted in current enhancement upon particle translocation. The counterion cloud around the nanoparticles is proposed to be the reason for current enhancement phenomena because associated counterion cloud is believed to increase the ion density inside the pore during particle translocation. Further, single particle diffusion events were also recorded at 0 mV voltage bias and 0 pA background ionic current with high signal-to-noise ratio as the particles moved down their concentration gradient. The ability of nanopore sensors to detect single particle diffusion can be extended to field-free analysis of biomolecules in their native state and at or near physiological salt concentrations.

  4. Habitat drives dispersal and survival of translocated juvenile desert tortoises

    Science.gov (United States)

    Nafus, Melia G.; Esque, Todd; Averill-Murray, Roy C.; Nussear, Kenneth E.; Swaisgood, Ronald R.

    2017-01-01

    1.In spite of growing reliance on translocations in wildlife conservation, translocation efficacy remains inconsistent. One factor that can contribute to failed translocations is releasing animals into poor quality or otherwise inadequate habitat.

  5. Cosmic Tachyon Background Radiation

    CERN Document Server

    Tomaschitz, R

    1999-01-01

    The equilibrium statistical mechanics of a background radiation of superluminal particles is investigated, based on a vectorial wave equation for tachyons of the Proca type. The partition function, the spectral energy density, and the various thermodynamic variables of an ideal Bose gas of tachyons in an open Robertson-Walker cosmology are derived. The negative mass square in the wave equation changes the frequency scaling in the Rayleigh-Jeans law, and there are also significant changes in the low temperature regime as compared to the microwave background, in particular in the caloric and thermal equations of state.

  6. Wildlife translocation: the conservation implications of pathogen exposure and genetic heterozygosity

    Directory of Open Access Journals (Sweden)

    Penedo M Cecilia T

    2011-02-01

    Full Text Available Abstract Background A key challenge for conservation biologists is to determine the most appropriate demographic and genetic management strategies for wildlife populations threatened by disease. We explored this topic by examining whether genetic background and previous pathogen exposure influenced survival of translocated animals when captive-bred and free-ranging bighorn sheep (Ovis canadensis were used to re-establish a population that had been extirpated in the San Andres Mountains in New Mexico, USA. Results Although the free-ranging source population had significantly higher multi-locus heterozygosity at 30 microsatellite loci than the captive bred animals, neither source population nor genetic background significantly influenced survival or cause of death. The presence of antibodies to a respiratory virus known to cause pneumonia was associated with increased survival, but there was no correlation between genetic heterozygosity and the presence of antibodies to this virus. Conclusions Although genetic theory predicts otherwise, increased heterozygosity was not associated with increased fitness (survival among translocated animals. While heterosis or genetic rescue effects may occur in F1 and later generations as the two source populations interbreed, we conclude that previous pathogen exposure was a more important marker than genetic heterozygosity for predicting survival of translocated animals. Every wildlife translocation is an experiment, and whenever possible, translocations should be designed and evaluated to test hypotheses that will further improve our understanding of how pathogen exposure and genetic variability influence fitness.

  7. Chromosomal Translocations in the Parasite Leishmania by a MRE11/RAD50-Independent Microhomology-Mediated End Joining Mechanism.

    Science.gov (United States)

    Laffitte, Marie-Claude N; Leprohon, Philippe; Hainse, Maripier; Légaré, Danielle; Masson, Jean-Yves; Ouellette, Marc

    2016-06-01

    The parasite Leishmania often relies on gene rearrangements to survive stressful environments. However, safeguarding a minimum level of genome integrity is important for cell survival. We hypothesized that maintenance of genomic integrity in Leishmania would imply a leading role of the MRE11 and RAD50 proteins considering their role in DNA repair, chromosomal organization and protection of chromosomes ends in other organisms. Attempts to generate RAD50 null mutants in a wild-type background failed and we provide evidence that this gene is essential. Remarkably, inactivation of RAD50 was possible in a MRE11 null mutant that we had previously generated, providing good evidence that RAD50 may be dispensable in the absence of MRE11. Inactivation of the MRE11 and RAD50 genes led to a decreased frequency of homologous recombination and analysis of the null mutants by whole genome sequencing revealed several chromosomal translocations. Sequencing of the junction between translocated chromosomes highlighted microhomology sequences at the level of breakpoint regions. Sequencing data also showed a decreased coverage at subtelomeric locations in many chromosomes in the MRE11-/-RAD50-/- parasites. This study demonstrates an MRE11-independent microhomology-mediated end-joining mechanism and a prominent role for MRE11 and RAD50 in the maintenance of genomic integrity. Moreover, we suggest the possible involvement of RAD50 in subtelomeric regions stability.

  8. Chromosomal Translocations in the Parasite Leishmania by a MRE11/RAD50-Independent Microhomology-Mediated End Joining Mechanism.

    Directory of Open Access Journals (Sweden)

    Marie-Claude N Laffitte

    2016-06-01

    Full Text Available The parasite Leishmania often relies on gene rearrangements to survive stressful environments. However, safeguarding a minimum level of genome integrity is important for cell survival. We hypothesized that maintenance of genomic integrity in Leishmania would imply a leading role of the MRE11 and RAD50 proteins considering their role in DNA repair, chromosomal organization and protection of chromosomes ends in other organisms. Attempts to generate RAD50 null mutants in a wild-type background failed and we provide evidence that this gene is essential. Remarkably, inactivation of RAD50 was possible in a MRE11 null mutant that we had previously generated, providing good evidence that RAD50 may be dispensable in the absence of MRE11. Inactivation of the MRE11 and RAD50 genes led to a decreased frequency of homologous recombination and analysis of the null mutants by whole genome sequencing revealed several chromosomal translocations. Sequencing of the junction between translocated chromosomes highlighted microhomology sequences at the level of breakpoint regions. Sequencing data also showed a decreased coverage at subtelomeric locations in many chromosomes in the MRE11-/-RAD50-/- parasites. This study demonstrates an MRE11-independent microhomology-mediated end-joining mechanism and a prominent role for MRE11 and RAD50 in the maintenance of genomic integrity. Moreover, we suggest the possible involvement of RAD50 in subtelomeric regions stability.

  9. DNA nanopore translocation in glutamate solutions

    NARCIS (Netherlands)

    Plesa, C.; Van Loo, N.; Dekker, C.

    2015-01-01

    Nanopore experiments have traditionally been carried out with chloride-based solutions. Here we introduce silver/silver-glutamate-based electrochemistry as an alternative, and study the viscosity, conductivity, and nanopore translocation characteristics of potassium-, sodium-, and lithium-glutamate

  10. Dudleya Variegata Translocation - San Diego [ds654

    Data.gov (United States)

    California Department of Resources — At Mission Trails Regional Park, a translocation project of Dudleya variegata was conducted in efforts to save the population from a private property undergoing...

  11. Translocation dynamics of a short polymer driven by an oscillating force.

    Science.gov (United States)

    Pizzolato, Nicola; Fiasconaro, Alessandro; Adorno, Dominique Persano; Spagnolo, Bernardo

    2013-02-07

    We study the translocation dynamics of a short polymer moving in a noisy environment and driven by an oscillating force. The dynamics is numerically investigated by solving a Langevin equation in a two-dimensional domain. We consider a phenomenological cubic potential with a metastable state to model the polymer-pore interaction and the entropic free energy barrier characterizing the translocation process. The mean first translocation time of the center of inertia of polymers shows a nonmonotonic behavior, with a minimum, as a function of the number of the monomers. The dependence of the mean translocation time on the polymer chain length shows a monotonically increasing behavior for high values of the number of monomers. Moreover, the translocation time shows a minimum as a function of the frequency of the oscillating forcing field for all the polymer lengths investigated. This finding represents the evidence of the resonant activation phenomenon in the dynamics of polymer translocation, whose occurrence is maintained for different values of the noise intensity.

  12. Monocyte activation, but not microbial translocation, is independently associated with markers of endovascular dysfunction in HIV-infected patients receiving cART

    DEFF Research Database (Denmark)

    Pedersen, Karin K; Manner, Ingjerd W; Seljeflot, Ingebjørg;

    2014-01-01

    BACKGROUND: Microbial translocation has been suggested as a driver of cardiovascular disease in HIV infection. We hypothesized that microbial translocation and the resulting monocyte activation would be associated with markers of endovascular dysfunction. METHODS: In 60 HIV-infected patients on c...

  13. Translocation pathways for inhaled asbestos fibers

    Directory of Open Access Journals (Sweden)

    Mantegazza F

    2008-01-01

    Full Text Available Abstract We discuss the translocation of inhaled asbestos fibers based on pulmonary and pleuro-pulmonary interstitial fluid dynamics. Fibers can pass the alveolar barrier and reach the lung interstitium via the paracellular route down a mass water flow due to combined osmotic (active Na+ absorption and hydraulic (interstitial pressure is subatmospheric pressure gradient. Fibers can be dragged from the lung interstitium by pulmonary lymph flow (primary translocation wherefrom they can reach the blood stream and subsequently distribute to the whole body (secondary translocation. Primary translocation across the visceral pleura and towards pulmonary capillaries may also occur if the asbestos-induced lung inflammation increases pulmonary interstitial pressure so as to reverse the trans-mesothelial and trans-endothelial pressure gradients. Secondary translocation to the pleural space may occur via the physiological route of pleural fluid formation across the parietal pleura; fibers accumulation in parietal pleura stomata (black spots reflects the role of parietal lymphatics in draining pleural fluid. Asbestos fibers are found in all organs of subjects either occupationally exposed or not exposed to asbestos. Fibers concentration correlates with specific conditions of interstitial fluid dynamics, in line with the notion that in all organs microvascular filtration occurs from capillaries to the extravascular spaces. Concentration is high in the kidney (reflecting high perfusion pressure and flow and in the liver (reflecting high microvascular permeability while it is relatively low in the brain (due to low permeability of blood-brain barrier. Ultrafine fibers (length

  14. Wildlife translocation: the conservation implications of pathogen exposure and genetic heterozygosity

    OpenAIRE

    Penedo M Cecilia T; Weisenberger Mara E; Boyce Walter M; Johnson Christine K

    2011-01-01

    Abstract Background A key challenge for conservation biologists is to determine the most appropriate demographic and genetic management strategies for wildlife populations threatened by disease. We explored this topic by examining whether genetic background and previous pathogen exposure influenced survival of translocated animals when captive-bred and free-ranging bighorn sheep (Ovis canadensis) were used to re-establish a population that had been extirpated in the San Andres Mountains in Ne...

  15. Liver Cirrhosis and Intestinal Bacterial Translocation

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    Intestinal barrier dysfunction, facilitating translocation of bacteria and bacterial products, plays an important role in the pathophysiology of liver cirrhosis and its complications. Intestinal defense system including microbial barrier, immunologic barrier, mechanical barrier, chemical barrier, plays an important role in the maintenance of intestinal function. Under normal circumstances, the intestinal barrier can prevent intestinal bacteria through the intestinal wall from spreading to the body. Severe infection, trauma, shock, cirrhosis, malnutrition, immune suppression conditions, intestinal bacteria and endotoxin translocation, can lead to multiple organ dysfunction. The intestinal microlfora is not only involved in the digestion of nutrients, but also in local immunity, forming a barrier against pathogenic microorganisms. The derangement of the gut microlfora may lead to microbial translocation, deifned as the passage of viable microorganisms or bacterial products from the intestinal lumen to the mesenteric lymph nodes and other extraintestinal sites. In patients with cirrhosis, primary and intestinal lfora imbalance, intestinal bacterial overgrowth, intestinal mucosal barrier dysfunction, endotoxemia is associated with weakened immunity.

  16. Nuclear translocation and retention of growth hormone

    DEFF Research Database (Denmark)

    Mertani, Hichem C; Raccurt, Mireille; Abbate, Aude

    2003-01-01

    We have previously demonstrated that GH is subject to rapid receptor-dependent nuclear translocation. Here, we examine the importance of ligand activation of the GH-receptor (GHR)-associated Janus kinase (JAK) 2 and receptor dimerization for hormone internalization and nuclear translocation by use...... of cells stably transfected with cDNA for the GHR. Staurosporine and herbimycin A treatment of cells did not affect the ability of GH to internalize but resulted in increased nuclear accumulation of hormone. Similarly, receptor mutations, which prevent the association and activation of JAK2, did not affect...... the ability of the hormone to internalize or translocate to the nucleus but resulted in increased nuclear accumulation of GH. These results were observed both by nuclear isolation and confocal laser scanning microscopy. Staurosporine treatment of cells in which human GH (hGH) was targeted to the cytoplasm...

  17. Rank Modulation for Translocation Error Correction

    CERN Document Server

    Farnoud, Farzad; Milenkovic, Olgica

    2012-01-01

    We consider rank modulation codes for flash memories that allow for handling arbitrary charge drop errors. Unlike classical rank modulation codes used for correcting errors that manifest themselves as swaps of two adjacently ranked elements, the proposed \\emph{translocation rank codes} account for more general forms of errors that arise in storage systems. Translocations represent a natural extension of the notion of adjacent transpositions and as such may be analyzed using related concepts in combinatorics and rank modulation coding. Our results include tight bounds on the capacity of translocation rank codes, construction techniques for asymptotically good codes, as well as simple decoding methods for one class of structured codes. As part of our exposition, we also highlight the close connections between the new code family and permutations with short common subsequences, deletion and insertion error-correcting codes for permutations and permutation arrays.

  18. DNA nanopore translocation in glutamate solutions

    Science.gov (United States)

    Plesa, C.; van Loo, N.; Dekker, C.

    2015-08-01

    Nanopore experiments have traditionally been carried out with chloride-based solutions. Here we introduce silver/silver-glutamate-based electrochemistry as an alternative, and study the viscosity, conductivity, and nanopore translocation characteristics of potassium-, sodium-, and lithium-glutamate solutions. We show that it has a linear response at typical voltages and can be used to detect DNA translocations through a nanopore. The glutamate anion also acts as a redox-capable thickening agent, with high-viscosity solutions capable of slowing down the DNA translocation process by up to 11 times, with a corresponding 7 time reduction in signal. These results demonstrate that glutamate can replace chloride as the primary anion in nanopore resistive pulse sensing.

  19. Polymer translocation through a nanopore: DPD study.

    Science.gov (United States)

    Yang, Kan; Vishnyakov, Aleksey; Neimark, Alexander V

    2013-04-04

    Translocation of a polymer chain through a narrow pore is explored using 3D explicit solvent dissipative particle dynamics simulation. We study the dependence of the translocation dynamics and translocation time τ on the chain length N, driving force magnitude E, and solvent quality. Two types of driving forces are considered: uniform hydrostatic force, which is applied equally to the chain and solvent particles, and uniform electrostatic force, which is applied selectively to the charged particles in the chain and oppositely charged counterions in the solvent. We concluded that the scaling correlations τ ~ E(-ξ) and τ ~ N(β) are valid only for coil-like chains. For globular chains, the exponents ξ and β could not be identified with a reasonable accuracy. While the found value of ξ agrees with published experimental results and does not depend on the driving force type, the exponent β depends on the driving force and solvent quality. This is explained by nonequilibrium effects, as in the systems considered, the time of translocation is comparable with the time of chain relaxation. These effects, manifested in the changes of chain conformation in the process of translocation, were analyzed on the basis of the variation of the gyration radii of cis and trans segments of the chain in normal and lateral directions. A prominent chain expansion was observed for coils and was insignificant for globules. This work demonstrates the feasibility of the 3D dissipative particle dynamics modeling of translocation phenomena and accounting for the electrostatic interactions with explicit counterions, as well as for the solvent quality, in a computationally efficient manner.

  20. Hyaluronan synthase mediates dye translocation across liposomal membranes

    Directory of Open Access Journals (Sweden)

    Medina Andria P

    2012-01-01

    Full Text Available Abstract Background Hyaluronan (HA is made at the plasma membrane and secreted into the extracellular medium or matrix by phospolipid-dependent hyaluronan synthase (HAS, which is active as a monomer. Since the mechanism by which HA is translocated across membranes is still unresolved, we assessed the presence of an intraprotein pore within HAS by adding purified Streptococcus equisimilis HAS (SeHAS to liposomes preloaded with the fluorophore Cascade Blue (CB. Results CB translocation (efflux was not observed with mock-purified material from empty vector control E. coli membranes, but was induced by SeHAS, purified from membranes, in a time- and dose-dependent manner. CB efflux was eliminated or greatly reduced when purified SeHAS was first treated under conditions that inhibit enzyme activity: heating, oxidization or cysteine modification with N-ethylmaleimide. Reduced CB efflux also occurred with SeHAS K48E or K48F mutants, in which alteration of K48 within membrane domain 2 causes decreased activity and HA product size. The above results used liposomes containing bovine cardiolipin (BCL. An earlier study testing many synthetic lipids found that the best activating lipid for SeHAS is tetraoleoyl cardiolipin (TO-CL and that, in contrast, tetramyristoyl cardiolipin (TM-CL is an inactivating lipid (Weigel et al, J. Biol. Chem. 281, 36542, 2006. Consistent with the effects of these CL species on SeHAS activity, CB efflux was more than 2-fold greater in liposomes made with TO-CL compared to TM-CL. Conclusions The results indicate the presence of an intraprotein pore in HAS and support a model in which HA is translocated to the exterior by HAS itself.

  1. A recurrent translocation is mediated by homologous recombination between HERV-H elements

    Directory of Open Access Journals (Sweden)

    Hermetz Karen E

    2012-01-01

    Full Text Available Abstract Background Chromosome rearrangements are caused by many mutational mechanisms; of these, recurrent rearrangements can be particularly informative for teasing apart DNA sequence-specific factors. Some recurrent translocations are mediated by homologous recombination between large blocks of segmental duplications on different chromosomes. Here we describe a recurrent unbalanced translocation casued by recombination between shorter homologous regions on chromosomes 4 and 18 in two unrelated children with intellectual disability. Results Array CGH resolved the breakpoints of the 6.97-Megabase (Mb loss of 18q and the 7.30-Mb gain of 4q. Sequencing across the translocation breakpoints revealed that both translocations occurred between 92%-identical human endogenous retrovirus (HERV elements in the same orientation on chromosomes 4 and 18. In addition, we find sequence variation in the chromosome 4 HERV that makes one allele more like the chromosome 18 HERV. Conclusions Homologous recombination between HERVs on the same chromosome is known to cause chromosome deletions, but this is the first report of interchromosomal HERV-HERV recombination leading to a translocation. It is possible that normal sequence variation in substrates of non-allelic homologous recombination (NAHR affects the alignment of recombining segments and influences the propensity to chromosome rearrangement.

  2. Tissue Nitrogen and Fructan Translocation in Bread Wheat

    Institute of Scientific and Technical Information of China (English)

    HOU You-liang; L.O'Brien; ZHONG Gai-rong

    2002-01-01

    Translocation of previously accumulated nitrogen and carbohydrates from vegetative tissue of the wheat plant is a major assimilate source for grain filling. This study was conducted to examine genotype differences in nitrogen and fructan translocation and their relationships to grain yield and protein content. Effects indicated that significant genotype differences existed for nitrogen accumulation at anthesis and fructan at milk stage and their translocation. Two high protein genotypes, Cunningham and PST90-19, accumulated more nitrogen before anthesis and had greater nitrogen translocation, but lower post-anthesis nitrogen uptake,than two low protein genotypes, SUN109A and TM56. Among plant parts, leaves were the major storage for tissue nitrogen and provided the overwhelming proportion of the total nitrogen translocation, whereas for fructan accumulation and translocation it was the stems. The two high protein genotypes had a higher percentage of their grain nitrogen derived from nitrogen translocation, while for the two low protein ones, it was from postanthesis nitrogen uptake and assimilation. Increasing nitrogen application increased nitrogen accumulation and translocation, but decreased fructan accumulation and translocation. High grain protein content was associated with high nitrogen translocation from leaves, stems and the total plant, while high grain yield was related to high fructan translocation from stems and the total plant. Fructan translocation was negatively correlated to grain protein content. Nitrogen and fructan translocation were not correlated with each other.

  3. Simultaneous localization of MLL, AF4 and ENL genes in interphase nuclei by 3D-FISH: MLL translocation revisited

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    Sun Jian-Sheng

    2006-01-01

    Full Text Available Abstract Background Haematological cancer is characterised by chromosomal translocation (e.g. MLL translocation in acute leukaemia and two models have been proposed to explain the origins of recurrent reciprocal translocation. The first, established from pairs of translocated genes (such as BCR and ABL, considers the spatial proximity of loci in interphase nuclei (static "contact first" model. The second model is based on the dynamics of double strand break ends during repair processes (dynamic "breakage first" model. Since the MLL gene involved in 11q23 translocation has more than 40 partners, the study of the relative positions of the MLL gene with both the most frequent partner gene (AF4 and a less frequent partner gene (ENL, should elucidate the MLL translocation mechanism. Methods Using triple labeling 3D FISH experiments, we have determined the relative positions of MLL, AF4 and ENL genes, in two lymphoblastic and two myeloid human cell lines. Results In all cell lines, the ENL gene is significantly closer to the MLL gene than the AF4 gene (with P value loci would indicate a greater probability of the occurrence of t(11;19(q23;p13.3 compared to t(4;11(q21;q23. However this is in contradiction to the epidemiology of 11q23 translocation. Conclusion The simultaneous multi-probe hybridization in 3D-FISH is a new approach in addressing the correlation between spatial proximity and occurrence of translocation. Our observations are not consistent with the static "contact first" model of translocation. The recently proposed dynamic "breakage first" model offers an attractive alternative explanation.

  4. Post-release dispersal in animal translocations: social attraction and the "vacuum effect".

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    Jean-Baptiste Mihoub

    Full Text Available Animal translocations are human-induced colonizations that can represent opportunities to contribute to the knowledge on the behavioral and demographic processes involved in the establishment of animal populations. Habitat selection behaviors, such as social cueing, have strong implications on dispersal and affect the establishment success of translocations. Using modeling simulations with a two-population network model (a translocated population and a remnant population, we investigated the consequences of four habitat selection strategies on post-translocation establishment probabilities in short- and long-lived species. Two dispersal strategies using social cues (conspecific attraction and habitat copying were compared to random and quality-based strategies. We measured the sensitivity of local extinctions to dispersal strategies, life cycles, release frequencies, remnant population and release group sizes, the proportion of breeders and the connectivity between populations. Our results indicate that social behaviors can compromise establishment as a result of post-release dispersal, particularly in long-lived species. This behavioral mechanism, the "vacuum effect", arises from increased emigration in populations that are small relative to neighboring populations, reducing their rate of population growth. The vacuum effect can drive small remnant populations to extinction when a translocated group is large. In addition, the magnitude of the vacuum effect varies non-linearly with connectivity. The vacuum effect represents a novel form of the behaviorally mediated Allee effect that can cause unexpected establishment failures or population extinctions in response to social cueing. Accounting for establishment probabilities as a conditional step to the persistence of populations would improve the accuracy of predicting the fates of translocated or natural (metapopulations.

  5. Post-release dispersal in animal translocations: social attraction and the "vacuum effect".

    Science.gov (United States)

    Mihoub, Jean-Baptiste; Robert, Alexandre; Le Gouar, Pascaline; Sarrazin, François

    2011-01-01

    Animal translocations are human-induced colonizations that can represent opportunities to contribute to the knowledge on the behavioral and demographic processes involved in the establishment of animal populations. Habitat selection behaviors, such as social cueing, have strong implications on dispersal and affect the establishment success of translocations. Using modeling simulations with a two-population network model (a translocated population and a remnant population), we investigated the consequences of four habitat selection strategies on post-translocation establishment probabilities in short- and long-lived species. Two dispersal strategies using social cues (conspecific attraction and habitat copying) were compared to random and quality-based strategies. We measured the sensitivity of local extinctions to dispersal strategies, life cycles, release frequencies, remnant population and release group sizes, the proportion of breeders and the connectivity between populations. Our results indicate that social behaviors can compromise establishment as a result of post-release dispersal, particularly in long-lived species. This behavioral mechanism, the "vacuum effect", arises from increased emigration in populations that are small relative to neighboring populations, reducing their rate of population growth. The vacuum effect can drive small remnant populations to extinction when a translocated group is large. In addition, the magnitude of the vacuum effect varies non-linearly with connectivity. The vacuum effect represents a novel form of the behaviorally mediated Allee effect that can cause unexpected establishment failures or population extinctions in response to social cueing. Accounting for establishment probabilities as a conditional step to the persistence of populations would improve the accuracy of predicting the fates of translocated or natural (meta)populations.

  6. Quantized biopolymer translocation through nanopores: departure from simple scaling

    CERN Document Server

    Melchionna, Simone; Fyta, Maria; Kaxiras, Efthimios; Succi, Sauro

    2009-01-01

    We discuss multiscale simulations of long biopolymer translocation through wide nanopores that can accommodate multiple polymer strands. The simulations provide clear evidence of folding quantization, namely, the translocation proceeds through multi-folded configurations characterized by a well-defined integer number of folds. As a consequence, the translocation time acquires a dependence on the average folding number, which results in a deviation from the single-exponent power-law characterizing single-file translocation through narrow pores. The mechanism of folding quantization allows polymers above a threshold length (approximately $1,000$ persistence lengths for double-stranded DNA) to exhibit cooperative behavior and as a result to translocate noticeably faster.

  7. Genes and translocations involved in POF.

    Science.gov (United States)

    Schlessinger, David; Herrera, Luisa; Crisponi, Laura; Mumm, Steven; Percesepe, Antonio; Pellegrini, Massimo; Pilia, Giuseppe; Forabosco, Antonino

    2002-08-15

    Changes at a single autosomal locus and many X-linked loci have been implicated in women with gonadal dysgenesis [premature ovarian failure (POF) with deficits in ovarian follicles]. For the chromosome 3 locus, a forkhead transcription factor gene (FOXL2) has been identified, in which lesions result in decreased follicles by haploinsufficiency. In contrast, sporadic X; autosomal translocations are distributed at many points on the X, but concentrate in a critical region on Xq. The association of the breakpoints with genes involved in ovarian function is thus far weak (in four analyzed cases) and has not been related to pathology in other POF patients. While many more translocations can be analyzed in detail as the human genome sequence is refined, it remains possible that translocations like X monosomy (Turner syndrome) lead to POF not by interrupting specific genes important in ovarian development, but by causing aberrations in pairing or X-inactivation during folliculogenesis. It is noted that the critical region has unusual features, neighboring the X-inactivation center and including an 18 Mb region of very low recombination. These suggest that chromosome dynamics in the region may be sensitive to structural changes, and when modified by translocations might provoke apoptosis at meiotic checkpoints. Choices among models for the etiology of POF should be feasible based on studies of ovarian follicle development and attrition in mouse models. Studies would prominently include gene expression profiling of developmental-specific pathways in nascent ovaries with controlled levels of Foxl2 and interacting proteins, or with defined changes in the X chromosome.

  8. Stepwise nucleosome translocation by RSC remodeling complexes.

    Science.gov (United States)

    Harada, Bryan T; Hwang, William L; Deindl, Sebastian; Chatterjee, Nilanjana; Bartholomew, Blaine; Zhuang, Xiaowei

    2016-02-19

    The SWI/SNF-family remodelers regulate chromatin structure by coupling the free energy from ATP hydrolysis to the repositioning and restructuring of nucleosomes, but how the ATPase activity of these enzymes drives the motion of DNA across the nucleosome remains unclear. Here, we used single-molecule FRET to monitor the remodeling of mononucleosomes by the yeast SWI/SNF remodeler, RSC. We observed that RSC primarily translocates DNA around the nucleosome without substantial displacement of the H2A-H2B dimer. At the sites where DNA enters and exits the nucleosome, the DNA moves largely along or near its canonical wrapping path. The translocation of DNA occurs in a stepwise manner, and at both sites where DNA enters and exits the nucleosome, the step size distributions exhibit a peak at approximately 1-2 bp. These results suggest that the movement of DNA across the nucleosome is likely coupled directly to DNA translocation by the ATPase at its binding site inside the nucleosome.

  9. Unforced polymer translocation compared to the forced case.

    Science.gov (United States)

    Lehtola, V V; Linna, R P; Kaski, K

    2010-03-01

    We present results for unforced polymer translocation from simulations using Langevin dynamics in two dimensions (2D) to four dimensions and stochastic rotation dynamics supporting hydrodynamic modes in three dimensions (3D). We compare our results to forced translocation and a simplified model where the polymer escapes from an infinite pore. The simple model shows that the scaling behavior of unforced translocation is independent of the dimension of the side to which the polymer is translocating. We find that, unlike its forced counterpart, unforced translocation dynamics is insensitive to pore design. Hydrodynamics is seen to markedly speed up the unforced translocation process but not to affect the scaling relations. Average mean-squared displacement shows scaling with average transition time in unforced but not in forced translocation. The waiting-time distribution in unforced translocation follows closely Poissonian distribution. Our measured transfer probabilities align well with those obtained from an equilibrium theory in 3D, but somewhat worse in 2D, where a polymer's relaxation toward equilibrium with respect to its translocation time is slower. Consequently, in stark contrast to forced translocation, unforced translocation is seen to remain close to equilibrium and shows clear universality.

  10. Financial costs of large carnivore translocations--accounting for conservation.

    Science.gov (United States)

    Weise, Florian J; Stratford, Ken J; van Vuuren, Rudolf J

    2014-01-01

    Human-carnivore conflict continues to present a major conservation challenge around the world. Translocation of large carnivores is widely implemented but remains strongly debated, in part because of a lack of cost transparency. We report detailed translocation costs for three large carnivore species in Namibia and across different translocation scenarios. We consider the effect of various parameters and factors on costs and translocation success. Total translocation cost for 30 individuals in 22 events was $80,681 (US Dollars). Median translocation cost per individual was $2,393, and $2,669 per event. Median cost per cheetah was $2,760 (n = 23), and $2,108 per leopard (n = 6). One hyaena was translocated at a cost of $1,672. Tracking technology was the single biggest cost element (56%), followed by captive holding and feeding. Soft releases, prolonged captivity and orphaned individuals also increased case-specific costs. A substantial proportion (65.4%) of the total translocation cost was successfully recovered from public interest groups. Less than half the translocations were confirmed successes (44.4%, 3 unknown) with a strong species bias. Four leopards (66.7%) were successfully translocated but only eight of the 20 cheetahs (40.0%) with known outcome met these strict criteria. None of the five habituated cheetahs was translocated successfully, nor was the hyaena. We introduce the concept of Individual Conservation Cost (ICC) and define it as the cost of one successfully translocated individual adjusted by costs of unsuccessful events of the same species. The median ICC for cheetah was $6,898 and $3,140 for leopard. Translocations are costly, but we demonstrate that they are not inherently more expensive than other strategies currently employed in non-lethal carnivore conflict management. We conclude that translocation should be one available option for conserving large carnivores, but needs to be critically evaluated on a case-by-case basis.

  11. Financial costs of large carnivore translocations--accounting for conservation.

    Directory of Open Access Journals (Sweden)

    Florian J Weise

    Full Text Available Human-carnivore conflict continues to present a major conservation challenge around the world. Translocation of large carnivores is widely implemented but remains strongly debated, in part because of a lack of cost transparency. We report detailed translocation costs for three large carnivore species in Namibia and across different translocation scenarios. We consider the effect of various parameters and factors on costs and translocation success. Total translocation cost for 30 individuals in 22 events was $80,681 (US Dollars. Median translocation cost per individual was $2,393, and $2,669 per event. Median cost per cheetah was $2,760 (n = 23, and $2,108 per leopard (n = 6. One hyaena was translocated at a cost of $1,672. Tracking technology was the single biggest cost element (56%, followed by captive holding and feeding. Soft releases, prolonged captivity and orphaned individuals also increased case-specific costs. A substantial proportion (65.4% of the total translocation cost was successfully recovered from public interest groups. Less than half the translocations were confirmed successes (44.4%, 3 unknown with a strong species bias. Four leopards (66.7% were successfully translocated but only eight of the 20 cheetahs (40.0% with known outcome met these strict criteria. None of the five habituated cheetahs was translocated successfully, nor was the hyaena. We introduce the concept of Individual Conservation Cost (ICC and define it as the cost of one successfully translocated individual adjusted by costs of unsuccessful events of the same species. The median ICC for cheetah was $6,898 and $3,140 for leopard. Translocations are costly, but we demonstrate that they are not inherently more expensive than other strategies currently employed in non-lethal carnivore conflict management. We conclude that translocation should be one available option for conserving large carnivores, but needs to be critically evaluated on a case-by-case basis.

  12. Guanine-nucleotide exchange on ribosome-bound elongation factor G initiates the translocation of tRNAs

    Directory of Open Access Journals (Sweden)

    Ehrenberg Måns

    2005-06-01

    Full Text Available Abstract Background During the translation of mRNA into polypeptide, elongation factor G (EF-G catalyzes the translocation of peptidyl-tRNA from the A site to the P site of the ribosome. According to the 'classical' model, EF-G in the GTP-bound form promotes translocation, while hydrolysis of the bound GTP promotes dissociation of the factor from the post-translocation ribosome. According to a more recent model, EF-G operates like a 'motor protein' and drives translocation of the peptidyl-tRNA after GTP hydrolysis. In both the classical and motor protein models, GDP-to-GTP exchange is assumed to occur spontaneously on 'free' EF-G even in the absence of a guanine-nucleotide exchange factor (GEF. Results We have made a number of findings that challenge both models. First, free EF-G in the cell is likely to be in the GDP-bound form. Second, the ribosome acts as the GEF for EF-G. Third, after guanine-nucleotide exchange, EF-G in the GTP-bound form moves the tRNA2-mRNA complex to an intermediate translocation state in which the mRNA is partially translocated. Fourth, subsequent accommodation of the tRNA2-mRNA complex in the post-translocation state requires GTP hydrolysis. Conclusion These results, in conjunction with previously published cryo-electron microscopy reconstructions of the ribosome in various functional states, suggest a novel mechanism for translocation of tRNAs on the ribosome by EF-G. Our observations suggest that the ribosome is a universal guanosine-nucleotide exchange factor for EF-G as previously shown for the class-II peptide-release factor 3.

  13. Guanine-nucleotide exchange on ribosome-bound elongation factor G initiates the translocation of tRNAs

    Science.gov (United States)

    Zavialov, Andrey V; Hauryliuk, Vasili V; Ehrenberg, Måns

    2005-01-01

    Background During the translation of mRNA into polypeptide, elongation factor G (EF-G) catalyzes the translocation of peptidyl-tRNA from the A site to the P site of the ribosome. According to the 'classical' model, EF-G in the GTP-bound form promotes translocation, while hydrolysis of the bound GTP promotes dissociation of the factor from the post-translocation ribosome. According to a more recent model, EF-G operates like a 'motor protein' and drives translocation of the peptidyl-tRNA after GTP hydrolysis. In both the classical and motor protein models, GDP-to-GTP exchange is assumed to occur spontaneously on 'free' EF-G even in the absence of a guanine-nucleotide exchange factor (GEF). Results We have made a number of findings that challenge both models. First, free EF-G in the cell is likely to be in the GDP-bound form. Second, the ribosome acts as the GEF for EF-G. Third, after guanine-nucleotide exchange, EF-G in the GTP-bound form moves the tRNA2-mRNA complex to an intermediate translocation state in which the mRNA is partially translocated. Fourth, subsequent accommodation of the tRNA2-mRNA complex in the post-translocation state requires GTP hydrolysis. Conclusion These results, in conjunction with previously published cryo-electron microscopy reconstructions of the ribosome in various functional states, suggest a novel mechanism for translocation of tRNAs on the ribosome by EF-G. Our observations suggest that the ribosome is a universal guanosine-nucleotide exchange factor for EF-G as previously shown for the class-II peptide-release factor 3. PMID:15985150

  14. Molecular dynamics and mutational analysis of the catalytic and translocation cycle of RNA polymerase

    Directory of Open Access Journals (Sweden)

    Kireeva Maria L

    2012-06-01

    Full Text Available Abstract Background During elongation, multi-subunit RNA polymerases (RNAPs cycle between phosphodiester bond formation and nucleic acid translocation. In the conformation associated with catalysis, the mobile “trigger loop” of the catalytic subunit closes on the nucleoside triphosphate (NTP substrate. Closing of the trigger loop is expected to exclude water from the active site, and dehydration may contribute to catalysis and fidelity. In the absence of a NTP substrate in the active site, the trigger loop opens, which may enable translocation. Another notable structural element of the RNAP catalytic center is the “bridge helix” that separates the active site from downstream DNA. The bridge helix may participate in translocation by bending against the RNA/DNA hybrid to induce RNAP forward movement and to vacate the active site for the next NTP loading. The transition between catalytic and translocation conformations of RNAP is not evident from static crystallographic snapshots in which macromolecular motions may be restrained by crystal packing. Results All atom molecular dynamics simulations of Thermus thermophilus (Tt RNAP reveal flexible hinges, located within the two helices at the base of the trigger loop, and two glycine hinges clustered near the N-terminal end of the bridge helix. As simulation progresses, these hinges adopt distinct conformations in the closed and open trigger loop structures. A number of residues (described as “switch” residues trade atomic contacts (ion pairs or hydrogen bonds in response to changes in hinge orientation. In vivo phenotypes and in vitro activities rendered by mutations in the hinge and switch residues in Saccharomyces cerevisiae (Sc RNAP II support the importance of conformational changes predicted from simulations in catalysis and translocation. During simulation, the elongation complex with an open trigger loop spontaneously translocates forward relative to the elongation complex with a

  15. Fibroblast growth factor receptor 2 translocations in intrahepatic cholangiocarcinoma.

    Science.gov (United States)

    Graham, Rondell P; Barr Fritcher, Emily G; Pestova, Ekaterina; Schulz, John; Sitailo, Leonid A; Vasmatzis, George; Murphy, Stephen J; McWilliams, Robert R; Hart, Steven N; Halling, Kevin C; Roberts, Lewis R; Gores, Gregory J; Couch, Fergus J; Zhang, Lizhi; Borad, Mitesh J; Kipp, Benjamin R

    2014-08-01

    Patients with cholangiocarcinoma often present with locally advanced or metastatic disease. There is a need for effective therapeutic strategies for advanced stage cholangiocarcinoma. Recently, FGFR2 translocations have been identified as a potential target for tyrosine kinase inhibitor therapies. This study evaluated 152 cholangiocarcinomas and 4 intraductal papillary biliary neoplasms of the bile duct for presence of FGFR2 translocations by fluorescence in situ hybridization and characterized the clinicopathologic features of cases with FGFR2 translocations. Thirteen (10 women, 3 men; 8%) of 156 biliary tumors harbored FGFR2 translocations, including 12 intrahepatic cholangiocarcinomas (12/96; 13%) and 1 intraductal papillary neoplasm of the bile duct. Histologically, cholangiocarcinomas with FGFR2 translocations displayed prominent intraductal growth (62%) or anastomosing tubular glands with desmoplasia (38%). Immunohistochemically, the tumors with FGFR2 translocations frequently showed weak and patchy expression of CK19 (77%). Markers of the stem cell phenotype in cholangiocarcinoma, HepPar1 and CK20, were negative in all cases. The median cancer-specific survival for patients whose tumors harbored FGFR2 translocations was 123 months compared to 37 months for cases without FGFR2 translocations (P = .039). This study also assessed 100 cholangiocarcinomas for ERBB2 amplification and ROS1 translocations. Of the cases tested, 3% and 1% were positive for ERBB2 amplification and ROS1 translocation, respectively. These results confirm that FGFR2, ERRB2, and ROS1 alterations are potential therapeutic targets for intrahepatic cholangiocarcinoma.

  16. Development of Triticum aestivum-Leymus racemosus translocation lines using gametocidal chromosomes

    Institute of Scientific and Technical Information of China (English)

    袁建华; 陈佩度; 刘大钧

    2003-01-01

    Specific chromosomes of certain Aegilops species introduced into wheat genome background may often facilitate chromosome breakage and refusion, and finally result in a variety of chromosome restructuring. Such a phenomenon is commonly called gametocidal effect of the chromosomes. The chromosome 2C of Ae. cylindrica is one of such chromosomes. In the present study, scab resistant wheat-L. racemosus addition lines involving chromosomes Lr.2 and Lr.7 were crossed to wheat-Ae. cylindrica disomic addition line Add2C. Then F1 hybrids were subsequently backcrossed with wheat cv "Chinese Spring". BC1 plants with chromosome structural aberration were identified by C-banding. In the self-pollinated progenies of these plants, three translocation lines were developed and characterized by mitotic and meiotic analysis combined with C-banding and fluorescent in situ hybridization (FISH) using biotin-labeled genomic DNA of L. racemosus as probe. Some other putative translocation lines to be further characterized were also found. The practicability and efficiency of the translocation between wheat and alien chromosomes induced by gametocidal chromosomes, as well as the potential use of the developed alien translocation lines were also discussed.

  17. DNA damage-induced translocation of S100A11 into the nucleus regulates cell proliferation

    Directory of Open Access Journals (Sweden)

    Ulbricht Tobias

    2010-12-01

    Full Text Available Abstract Background Proteins are able to react in response to distinct stress stimuli by alteration of their subcellular distribution. The stress-responsive protein S100A11 belongs to the family of multifunctional S100 proteins which have been implicated in several key biological processes. Previously, we have shown that S100A11 is directly involved in DNA repair processes at damaged chromatin in the nucleus. To gain further insight into the underlying mechanism subcellular trafficking of S100A11 in response to DNA damage was analyzed. Results We show that DNA damage induces a nucleolin-mediated translocation of S100A11 from the cytoplasm into the nucleus. This translocation is impeded by inhibition of the phosphorylation activity of PKCα. Translocation of S100A11 into the nucleus correlates with an increased cellular p21 protein level. Depletion of nucleolin by siRNA severely impairs translocation of S100A11 into the nucleus resulting in a decreased p21 protein level. Additionally, cells lacking nucleolin showed a reduced colony forming capacity. Conclusions These observations suggest that regulation of the subcellular distribution of S100A11 plays an important role in the DNA damage response and p21-mediated cell cycle control.

  18. Cosmic microwave background theory.

    Science.gov (United States)

    Bond, J R

    1998-01-01

    A long-standing goal of theorists has been to constrain cosmological parameters that define the structure formation theory from cosmic microwave background (CMB) anisotropy experiments and large-scale structure (LSS) observations. The status and future promise of this enterprise is described. Current band-powers in -space are consistent with a DeltaT flat in frequency and broadly follow inflation-based expectations. That the levels are approximately (10(-5))2 provides strong support for the gravitational instability theory, while the Far Infrared Absolute Spectrophotometer (FIRAS) constraints on energy injection rule out cosmic explosions as a dominant source of LSS. Band-powers at 100 suggest that the universe could not have re-ionized too early. To get the LSS of Cosmic Background Explorer (COBE)-normalized fluctuations right provides encouraging support that the initial fluctuation spectrum was not far off the scale invariant form that inflation models prefer: e.g., for tilted Lambda cold dark matter sequences of fixed 13-Gyr age (with the Hubble constant H0 marginalized), ns = 1.17 +/- 0.3 for Differential Microwave Radiometer (DMR) only; 1.15 +/- 0.08 for DMR plus the SK95 experiment; 1.00 +/- 0.04 for DMR plus all smaller angle experiments; 1.00 +/- 0.05 when LSS constraints are included as well. The CMB alone currently gives weak constraints on Lambda and moderate constraints on Omegatot, but theoretical forecasts of future long duration balloon and satellite experiments are shown which predict percent-level accuracy among a large fraction of the 10+ parameters characterizing the cosmic structure formation theory, at least if it is an inflation variant.

  19. Formation of complex and unstable chromosomal translocations in yeast.

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    Kristina H Schmidt

    Full Text Available Genome instability, associated with chromosome breakage syndromes and most human cancers, is still poorly understood. In the yeast Saccharomyces cerevisiae, numerous genes with roles in the preservation of genome integrity have been identified. DNA-damage-checkpoint-deficient yeast cells that lack Sgs1, a RecQ-like DNA helicase related to the human Bloom's-syndrome-associated helicase BLM, show an increased rate of genome instability, and we have previously shown that they accumulate recurring chromosomal translocations between three similar genes, CAN1, LYP1 and ALP1. Here, the chromosomal location, copy number and sequence similarity of the translocation targets ALP1 and LYP1 were altered to gain insight into the formation of complex translocations. Among 844 clones with chromosomal rearrangements, 93 with various types of simple and complex translocations involving CAN1, LYP1 and ALP1 were identified. Breakpoint sequencing and mapping showed that the formation of complex translocation types is strictly dependent on the location of the initiating DNA break and revealed that complex translocations arise via a combination of interchromosomal translocation and template-switching, as well as from unstable dicentric intermediates. Template-switching occurred between sequences on the same chromosome, but was inhibited if the genes were transferred to different chromosomes. Unstable dicentric translocations continuously gave rise to clones with multiple translocations in various combinations, reminiscent of intratumor heterogeneity in human cancers. Base substitutions and evidence of DNA slippage near rearrangement breakpoints revealed that translocation formation can be accompanied by point mutations, and their presence in different translocation types within the same clone provides evidence that some of the different translocation types are derived from each other rather than being formed de novo. These findings provide insight into eukaryotic

  20. Another reptile translocation to a national park

    Directory of Open Access Journals (Sweden)

    W.R. Branch

    1990-10-01

    Full Text Available On 4 May 1988 a sub-adult (50 mm snout-vent length, 42 mm tail Jones' girdled lizard Cordylus tropidosternum jonesi was collected in a pile of wood being off-loaded at the new restcamp in the Karoo National Park, Beaufort West. The wood had been transported by lorry from the Kruger National Park. The specimen is deposited in the herpetological collection of the Port Elizabeth Museum (PEM R 4584. Jones' girdled lizard is a small, arboreal cordylid that shelters under tree bark and in hollow logs. It is common and widely-distributed in the Kruger National Park (Pienaar, Haacke & Jacobsen 1983, The Reptiles of the Kruger National Park, 3rd edition. Pretoria: National Parks Board and adjacent lowveld, being replaced in northern Zimbabwe and East Africa by the nominate race. Hewitt & Power (1913, Transactions of the Royal Society of South Africa 3: 147-176, 1913 reported a similar translocation of the species to Kimberley in association with timber brought to the diamond mining camps. One of us noted recently the ease and danger of the unwitting spread of commensal reptile species into conservation areas (Branch 1978, Koedoe 30: 165, and this is confirmed by this additional example. We recommend that should similar shipments of wood be considered essential, then they be fumigated to prevent the translocation of other alien organisms that may potentially have more dangerous consequences.

  1. Genomic hallmarks of genes involved in chromosomal translocations in hematological cancer.

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    Mikhail Shugay

    Full Text Available Reciprocal chromosomal translocations (RCTs leading to the formation of fusion genes are important drivers of hematological cancers. Although the general requirements for breakage and fusion are fairly well understood, quantitative support for a general mechanism of RCT formation is still lacking. The aim of this paper is to analyze available high-throughput datasets with computational and robust statistical methods, in order to identify genomic hallmarks of translocation partner genes (TPGs. Our results show that fusion genes are generally overexpressed due to increased promoter activity of 5' TPGs and to more stable 3'-UTR regions of 3' TPGs. Furthermore, expression profiling of 5' TPGs and of interaction partners of 3' TPGs indicates that these features can help to explain tissue specificity of hematological translocations. Analysis of protein domains retained in fusion proteins shows that the co-occurrence of specific domain combinations is non-random and that distinct functional classes of fusion proteins tend to be associated with different components of the gene fusion network. This indicates that the configuration of fusion proteins plays an important role in determining which 5' and 3' TPGs will combine in specific fusion genes. It is generally accepted that chromosomal proximity in the nucleus can explain the specific pairing of 5' and 3' TPGS and the recurrence of hematological translocations. Using recently available data for chromosomal contact probabilities (Hi-C we show that TPGs are preferentially located in early replicated regions and occupy distinct clusters in the nucleus. However, our data suggest that, in general, nuclear position of TPGs in hematological cancers explains neither TPG pairing nor clinical frequency. Taken together, our results support a model in which genomic features related to regulation of expression and replication timing determine the set of candidate genes more likely to be translocated in

  2. Translocation as a species conservation tool: Status and strategy

    Science.gov (United States)

    Griffith, B.; Scott, J.M.; Carpenter, J.W.; Reed, C.

    1989-01-01

    Surveys of recent (1973 to 1986) intentional releases of native birds and mammals to the wild in Australia, Canada, Hawaii, New Zealand, and the United States, were conducted to document current activities, identify factors associated with success, and suggest guidelines for enhancing future work. Nearly 700 translocations were conducted each year. Native game species constituted percent of translocations and were more successful (86 percent) than were translocations of threatened, endangered, or sensitive species (46 percent). Knowledge of habitat quality, location of release area within the species range, number of animals released, program length, and reproductive traits, allowed currect classification of 81 percent of observed translocations as successful or not.

  3. Obstacle Effects on One-Dimensional Translocation of ATPase

    Institute of Scientific and Technical Information of China (English)

    WANG Xian-Ju; AI Bao-Quan; LIU Liang-Gang

    2002-01-01

    We apply a general random walk model to the study of the ATPase's one-dimensional translocation along obstacle biological environment, and show the effects of random obstacles on the ATPase translocation along single stranded DNA. We find that the obstacle environment can reduce the lifetime of ATPase lattice-bound state which results in the inhibition of ATPase activity. We also carry out the ranges of rate constant of ATPase unidirectonal translocation and bidirectional translocation. Our results are consistent with the experiments and relevant theoretical consideration, and can be used to explain some physiological phenomena.

  4. Calreticulin Translocation Aggravates Endoplasmic Reticulum Stress-associated Apoptosis during Cardiomyocyte Hypoxia/Reoxygenation

    Institute of Scientific and Technical Information of China (English)

    Fei-Fei Xu; Xiu-Hua Liu

    2015-01-01

    Background:Calreticulin (CRT) is major Ca2+-binding chaperone mainly resident in the endoplasmic reticulum (ER) lumen.Recently,it has been shown that non-ER CRT regulates a wide array of cellular responses.We previously found that CRT was up-regulated during hypoxia/reoxygenation (H/R) and this study was aimed to investigate whether CRT nuclear translocation aggravates ER stress (ERS)-associated apoptosis during H/R injury in neonatal rat cardiomyocytes.Methods:Apoptosis rate and lactate dehydrogenase (LDH) leakage in culture medium were measured as indices of cell injury.Immunofluorescence staining showed the morphological changes of ER and intracellular translocation of CRT.Western blotting or reverse transcription polymerase chain reaction was used to detect the expression of target molecules.Results:Compared with control,H/R increased apoptosis rate and LDH activity.The ER became condensed and bubbled,and CRT translocated to the nucleus.Western blotting showed up-regulation of CRT,Nrf2,activating transcription factor 4 (ATF4),CHOP and caspase-12 expression after H/R.Exogenous CRT overexpression induced by plasmid transfection before H/R increased cell apoptosis,LDH leakage,ER disorder,CRT nuclear translocation and the expression of ERS-associated molecules.However,administration of the ERS inhibitor,taurine,or CRT siRNA alleviated cell injury,ER disorder,and inhibited ERS-associated apoptosis.Conclusions:Our results indicated that during H/R stress,CRT translocation increases cell apoptosis and LDH leakage,aggravates ER disorder,up-regulates expression of nuclear transcription factors,Nrf2 and ATF4,and activates ERS-associated apoptosis.

  5. Chromosome translocations measured by fluorescence in-situ hybridization: A promising biomarker

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, J.N.; Straume, T.

    1995-10-01

    A biomarker for exposure and risk assessment would be most useful if it employs an endpoint that is highly quantitative, is stable with time, and is relevant to human risk. Recent advances in chromosome staining using fluorescence in situ hybridization (FISH) facilitate fast and reliable measurement of reciprocal translocations, a kind of DNA damage linked to both prior exposure and risk. In contrast to other biomarkers available, the frequency of reciprocal translocations in individuals exposed to whole-body radiation is stable with time post exposure, has a rather small inter-individual variability, and can be measured accurately at the low levels. Here, the authors discuss results from their studies demonstrating that chromosome painting can be used to reconstruct radiation dose for workers exposed within the dose limits, for individuals exposed a long time ago, and even for those who have been diagnosed with leukemia but not yet undergone therapy.

  6. Ratchet rectification effect on the translocation of a flexible polyelectrolyte chain.

    Science.gov (United States)

    Mondal, Debasish; Muthukumar, M

    2016-08-28

    We report a three dimensional Langevin dynamics simulation of a uniformly charged flexible polyelectrolyte chain, translocating through an asymmetric narrow channel with periodically varying cross sections under the influence of a periodic external electric field. When reflection symmetry of the channel is broken, a rectification effect is observed with a favored direction for the chain translocation. For a given volume of the channel unit and polymer length, the rectification occurs below a threshold frequency of the external periodic driving force. We have also observed that the extent of the rectification varies non-monotonically with increasing molecular weight and the strength of geometric asymmetry of the channel. Observed non-monotonicity of the rectification performance has been interpreted in terms of a competition between two effects arising from the channel asymmetry and change in conformational entropy. An analytical model is presented with predictions consistent with the simulation results.

  7. Background sources at PEP

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, H.; Schwitters, R.F.; Toner, W.T.

    1988-01-01

    Important sources of background for PEP experiments are studied. Background particles originate from high-energy electrons and positrons which have been lost from stable orbits, ..gamma..-rays emitted by the primary beams through bremsstrahlung in the residual gas, and synchrotron radiation x-rays. The effect of these processes on the beam lifetime are calculated and estimates of background rates at the interaction region are given. Recommendations for the PEP design, aimed at minimizing background are presented. 7 figs., 4 tabs.

  8. Over half of breakpoints in gene pairs involved in cancer-specific recurrent translocations are mapped to human chromosomal fragile sites

    Directory of Open Access Journals (Sweden)

    Pierce Levi CT

    2009-01-01

    Full Text Available Abstract Background Gene rearrangements such as chromosomal translocations have been shown to contribute to cancer development. Human chromosomal fragile sites are regions of the genome especially prone to breakage, and have been implicated in various chromosome abnormalities found in cancer. However, there has been no comprehensive and quantitative examination of the location of fragile sites in relation to all chromosomal aberrations. Results Using up-to-date databases containing all cancer-specific recurrent translocations, we have examined 444 unique pairs of genes involved in these translocations to determine the correlation of translocation breakpoints and fragile sites in the gene pairs. We found that over half (52% of translocation breakpoints in at least one gene of these gene pairs are mapped to fragile sites. Among these, we examined the DNA sequences within and flanking three randomly selected pairs of translocation-prone genes, and found that they exhibit characteristic features of fragile DNA, with frequent AT-rich flexibility islands and the potential of forming highly stable secondary structures. Conclusion Our study is the first to examine gene pairs involved in all recurrent chromosomal translocations observed in tumor cells, and to correlate the location of more than half of breakpoints to positions of known fragile sites. These results provide strong evidence to support a causative role for fragile sites in the generation of cancer-specific chromosomal rearrangements.

  9. Building Background Knowledge

    Science.gov (United States)

    Neuman, Susan B.; Kaefer, Tanya; Pinkham, Ashley

    2014-01-01

    This article make a case for the importance of background knowledge in children's comprehension. It suggests that differences in background knowledge may account for differences in understanding text for low- and middle-income children. It then describes strategies for building background knowledge in the age of common core standards.

  10. Pb distribution and translocation in Jiaozhou Bay

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The trends of distribution, translocation and seasonal change of heavy metal Pb were studied based on the surface and bottom water sampling in Jiaozhou Bay in 1979, and compared with those in 1990's. The results showed that the source of Pb in the bay was from wastewater and sewage in the east of Jiaozhou Bay from ocean vessels. Pb concentration was higher in spring and lower in summer and autumn, and remained stable through sedimentation in the bottom layer. The overall water quality was good in 1970's. Compared with the environmental monitoring data of 1995-1999, Pb pollution had become serious. Therefore, more efforts should be made to protect the bay from Pb pollution.

  11. Cadmium uptake and translocation in seedlings of near isogenic lines of durum wheat that differ in grain cadmium accumulation

    Directory of Open Access Journals (Sweden)

    Taylor Gregory J

    2004-04-01

    Full Text Available Abstract Background Cadmium (Cd concentrations in durum wheat (Triticum turgidum L. var durum grain grown in North American prairie soils often exceed proposed international trade standards. To understand the physiological processes responsible for elevated Cd accumulation in shoots and grain, Cd uptake and translocation were studied in seedlings of a pair of near-isogenic durum wheat lines, high and low for Cd accumulation in grain. Results In short-term studies (109Cd-labelled nutrient solutions, there were no differences between lines in time- or concentration-dependent 109Cd accumulation by roots. In contrast, rates of 109Cd translocation from roots to shoots following longer exposure (48–60 h were 1.8-fold higher in the high Cd-accumulating line, despite equal whole-plant 109Cd accumulation in the lines. Over the same period, the 109Cd concentration in root-pressure xylem exudates was 1.7 to 1.9-fold higher in the high Cd-accumulating line. There were no differences between the lines in 65Zn accumulation or partitioning that could account for the difference between lines in 109Cd translocation. Conclusion These results suggest that restricted root-to-shoot Cd translocation may limit Cd accumulation in durum wheat grain by directly controlling Cd translocation from roots during grain filling, or by controlling the size of shoot Cd pools that can be remobilised to the grain.

  12. Intestinal translocation of Streptococcus suis type 2 EF+ in pigs

    NARCIS (Netherlands)

    Swildens, B.; Stockhofe-Zurwieden, N.; Meulen, van der J.; Wisselink, H.J.; Nielen, M.; Niewold, T.A.

    2004-01-01

    Sepsis with subsequent multisystem organ failure after translocation of bacteria from the gut is a serious risk associated with stress situations. We showed that intestinal bacterial translocation could be one of the pathways for pathogenic Streptococcus suis infections in the pig. In 24 piglets wei

  13. Label Free Chromosome Translocation Detection with Silicon nanowires

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Andersen, Karsten Brandt; Frøhling, Kasper Bayer;

    is a Fluorescent In Situ Hybridization, which is laborious and involves use of expensive reagents [1]. Here we present a label free technique for detection of chromosome translocations. As a proof of concept detection of chromosome translocation between chromosome 3 (Chr3) and chromosome 9 (Chr9) was chosen....

  14. Strandwise translocation of a DNA glycosylase on undamaged DNA

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Yan; Nam, Kwangho; Spong, Marie C.; Banerjee, Anirban; Sung, Rou-Jia; Zhang, Michael; Karplus, Martin; Verdine, Gregory L. (Harvard)

    2012-05-14

    Base excision repair of genotoxic nucleobase lesions in the genome is critically dependent upon the ability of DNA glycosylases to locate rare sites of damage embedded in a vast excess of undamaged DNA, using only thermal energy to fuel the search process. Considerable interest surrounds the question of how DNA glycosylases translocate efficiently along DNA while maintaining their vigilance for target damaged sites. Here, we report the observation of strandwise translocation of 8-oxoguanine DNA glycosylase, MutM, along undamaged DNA. In these complexes, the protein is observed to translocate by one nucleotide on one strand while remaining untranslocated on the complementary strand. We further report that alterations of single base-pairs or a single amino acid substitution (R112A) can induce strandwise translocation. Molecular dynamics simulations confirm that MutM can translocate along DNA in a strandwise fashion. These observations reveal a previously unobserved mode of movement for a DNA-binding protein along the surface of DNA.

  15. Multistep Current Signal in Protein Translocation through Graphene Nanopores

    KAUST Repository

    Bonome, Emma Letizia

    2015-05-07

    © 2015 American Chemical Society. In nanopore sensing experiments, the properties of molecules are probed by the variation of ionic currents flowing through the nanopore. In this context, the electronic properties and the single-layer thickness of graphene constitute a major advantage for molecule characterization. Here we analyze the translocation pathway of the thioredoxin protein across a graphene nanopore, and the related ionic currents, by integrating two nonequilibrium molecular dynamics methods with a bioinformatic structural analysis. To obtain a qualitative picture of the translocation process and to identify salient features we performed unsupervised structural clustering on translocation conformations. This allowed us to identify some specific and robust translocation intermediates, characterized by significantly different ionic current flows. We found that the ion current strictly anticorrelates with the amount of pore occupancy by thioredoxin residues, providing a putative explanation of the multilevel current scenario observed in recently published translocation experiments.

  16. Chaperone-assisted translocation of flexible polymers in three dimensions

    CERN Document Server

    Suhonen, P M

    2016-01-01

    Polymer translocation through a nanometer-scale pore assisted by chaperones binding to the polymer is a process encountered in vivo for proteins. Studying the relevant models by computer simulations is computationally demanding. Accordingly, previous studies are either for stiff polymers in three dimensions or flexible polymers in two dimensions. Here, we study chaperone-assisted translocation of flexible polymers in three dimensions using Langevin dynamics. We show that differences in binding mechanisms, more specifically, whether a chaperone can bind to a single or multiple sites on the polymer, lead to substantial differences in translocation dynamics in three dimensions. We show that the single-binding mode leads to dynamics that is very much like that in the constant-force driven translocation and accordingly mainly determined by tension propagation on the cis side. We obtain $\\beta \\approx 1.26$ for the exponent for the scaling of the translocation time with polymer length. This fairly low value can be ...

  17. Translocations of amphibians: Proven management method or experimental technique

    Science.gov (United States)

    Seigel, Richard A.; Dodd, C. Kenneth

    2002-01-01

    In an otherwise excellent review of metapopulation dynamics in amphibians, Marsh and Trenham (2001) make the following provocative statements (emphasis added): If isolation effects occur primarily in highly disturbed habitats, species translocations may be necessary to promote local and regional population persistence. Because most amphibians lack parental care, they areprime candidates for egg and larval translocations. Indeed, translocations have already proven successful for several species of amphibians. Where populations are severely isolated, translocations into extinct subpopulations may be the best strategy to promote regional population persistence. We take issue with these statements for a number of reasons. First, the authors fail to cite much of the relevant literature on species translocations in general and for amphibians in particular. Second, to those unfamiliar with current research in amphibian conservation biology, these comments might suggest that translocations are a proven management method. This is not the case, at least in most instances where translocations have been evaluated for an appropriate period of time. Finally, the authors fail to point out some of the negative aspects of species translocation as a management method. We realize that Marsh and Trenham's paper was not concerned primarily with translocations. However, because Marsh and Trenham (2001) made specific recommendations for conservation planners and managers (many of whom are not herpetologists or may not be familiar with the pertinent literature on amphibians), we believe that it is essential to point out that not all amphibian biologists are as comfortable with translocations as these authors appear to be. We especially urge caution about advocating potentially unproven techniques without a thorough review of available options.

  18. 40 CFR 798.5955 - Heritable translocation test in drosophila melanogaster.

    Science.gov (United States)

    2010-07-01

    ... drosophila melanogaster. 798.5955 Section 798.5955 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY....5955 Heritable translocation test in drosophila melanogaster. (a) Purpose. The heritable translocation test in Drosophila measures the induction of chromosomal translocations in germ cells of...

  19. Bacterial Translocation and Change in Intestinal Permeability in Patients after Abdominal Surgery

    Institute of Scientific and Technical Information of China (English)

    Zhi QIAO; Zhanliang LI; Jiye LI; Lianrong LU; Yi LV; Junyou LI

    2009-01-01

    sely related with bacterial translocation. Intestinal bacterial translocation (most commonly E. coli) might occur at early stage (2 h) after ab-dominal surgery. Postoperative SIRS and infection might bear a close relationship with bacterial translocation.

  20. MODY-like diabetes associated with an apparently balanced translocation: possible involvement of MPP7 gene and cell polarity in the pathogenesis of diabetes

    Directory of Open Access Journals (Sweden)

    Bartov Guy

    2009-02-01

    Full Text Available Abstract Background Characterization of disease-associated balanced translocations has led to the discovery of genes responsible for many disorders, including syndromes that include various forms of diabetes mellitus. We studied a man with unexplained maturity onset diabetes of the young (MODY-like diabetes and an apparently balanced translocation [46,XY,t(7;10(q22;p12] and sought to identify a novel diabetes locus by characterizing the translocation breakpoints. Results Mutations in coding exons and splice sites of known MODY genes were first ruled out by PCR amplification and DNA sequencing. Fluorescent in situ hybridization (FISH studies demonstrated that the translocation did not disrupt two known diabetes-related genes on 10p12. The translocation breakpoints were further mapped to high resolution using FISH and somatic cell hybrids and the junctions PCR-amplified and sequenced. The translocation did not disrupt any annotated transcription unit. However, the chromosome 10 breakpoint was 220 kilobases 5' to the Membrane Protein, Palmitoylated 7 (MPP7 gene, which encodes a protein required for proper cell polarity. This biological function is shared by HNF4A, a known MODY gene. Databases show MPP7 is highly expressed in mouse pancreas and is expressed in human islets. The translocation did not appear to alter lymphoblastoid expression of MPP7 or other genes near the breakpoints. Conclusion The balanced translocation and MODY-like diabetes in the proband could be coincidental. Alternatively, the translocation may cause islet cell dysfunction by altering MPP7 expression in a subtle or tissue-specific fashion. The potential roles of MPP7 mutations in diabetes and perturbed islet cell polarity in insulin secretion warrant further study.

  1. Translocations used to generate chromosome segment duplications in Neurospora can disrupt genes and create novel open reading frames

    Indian Academy of Sciences (India)

    Parmit K Singh; Srividhya V Iyer; T Naga Sowjanya; B Kranthi Raj; Durgadas P Kasbekar

    2010-12-01

    In Neurospora crassa, crosses between normal sequence strains and strains bearing some translocations can yield progeny bearing a duplication (Dp) of the translocated chromosome segment. Here, 30 breakpoint junction sequences of 12 Dp-generating translocations were determined. The breakpoints disrupted 13 genes (including predicted genes), and created 10 novel open reading frames. Insertion of sequences from LG III into LG I as translocation T(UK818) disrupts the eat-3 gene, which is the ortholog of the Podospora anserine gene ami1. Since ami1-homozygous Podospora crosses were reported to increase the frequency of repeat-induced point mutation (RIP), we performed crosses homozygous for a deficiency in eat-3 to test for a corresponding increase in RIP frequency. However, our results suggested that, unlike in Podospora, the eat-3 gene might be essential for ascus development in Neurospora. Duplication–heterozygous crosses are generally barren in Neurospora; however, by using molecular probes developed in this study, we could identify Dp segregants from two different translocation–heterozygous crosses, and using these we found that the barren phenotype of at least some duplication–heterozygous crosses was incompletely penetrant.

  2. Translocation as a tool for mitigating conflict with leopards in human-dominated landscapes of India.

    Science.gov (United States)

    Athreya, Vidya; Odden, Morten; Linnell, John D C; Karanth, K Ullas

    2011-02-01

    We examined the efficacy of a translocation program in which large numbers of leopards (Panthera pardus fusca) were trapped in human-dominated landscapes where livestock attacks were common and human attacks rare and released into adjoining forested areas in an attempt to reduce leopard presence and mitigate conflicts at the capture site. In the year starting in February of 2001, 29 leopards were captured in the human-dominated rural landscape of the Junnar region (4275 km(2) , 185 people/km(2) ), Maharashtra, India, and released an average of 39.5 km away in adjoining forests. Eleven leopards were also relocated to the same forests from other districts. Prior to the large-scale translocation program, an average of four leopard attacks on humans occurred each year between 1993 and 2001. After the translocation program was initiated, the average increased substantially to 17 attacks. Linear and logistic models showed that attack frequency increased in Junnar following nearby releases of leopards and decreased when leopards were removed for releases far away; that attacks became more lethal when the number of leopards introduced from other districts increased; and that attacks were most likely to occur in the regions where the largest number of leopards had been introduced from other areas. These results suggest that leopards did not stay at the release sites and that translocation induced attacks on people. Potential explanations for these results include increased aggression induced by stress of the translocation process, movement through unfamiliar human-dominated landscapes following release, and loss of fear of humans due to familiarity with humans acquired during captivity. Our results show that reactive solutions to attacks on humans by leopards, such as translocation, could in fact increase human-leopard conflict. Measures to reduce human-carnivore conflicts may include more effective compensation procedures to pay livestock owners for the loss of animals to

  3. The Persistence of FISH Translocations for Retrospective Biological Dosimetry after Simulated Whole or Partial Body Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero-Carbajal, Y.C.; Moquet, J.E.; Edwards, A.A.; Lloyd, D.C

    1998-07-01

    High acute whole and partial body accidental irradiations were simulated by in vitro irradiation of blood. Lymphocyte culture times were extended from 48 h to 72 h and 96 h to simulate the elimination of chromosomal damage that occurs over time in vivo following successive cell divisions. The yields of stable translocations involving chromosomes 2, 3 and 5 were scored by the FISH method together with full genome dicentrics. With simulated whole body irradiation the yieldsof dicentrics fell sharply with successive cell divisions whilst translocation frequencies remained constant. With partial irradiation both dicentric and translocation yields reduced. This may be explained by the hypothesis that with homogeneous irradiation at high doses the distributions of stable and unstable aberrations are Poisson and independent whilst with partial exposure their distributions are linked because both types are confined to the irradiated fraction of cells. This has highlighted a possible limitation in the use of FISH for retrospective dosimetry and may explain instances where the method has been reported to underestimate dose when compared with contemporary dosimetry. (author)

  4. Palindrome-mediated Translocations in Humans: A New Mechanistic Model for Gross Chromosomal Rearrangements

    Directory of Open Access Journals (Sweden)

    Hidehito Inagaki

    2016-07-01

    Full Text Available Palindromic DNA sequences, which can form secondary structures, are widely distributed in the human genome. Although the nature of the secondary structure—single-stranded hairpin or double-stranded cruciform—has been extensively investigated in vitro, the existence of such unusual non-B DNA in vivo remains controversial. Here, we review palindrome-mediated gross chromosomal rearrangements possibly induced by non-B DNA in humans. Recent advances in next-generation sequencing have not yet overcome the difficulty of palindromic sequence analysis. However, a dozen palindromic AT-rich repeat (PATRR sequences have been identified at the breakpoints of recurrent or non-recurrent chromosomal translocations in humans. The breakages always occur at the center of the palindrome. Analyses of polymorphisms within the palindromes indicate that the symmetry and length of the palindrome affect the frequency of the de novo occurrence of these palindrome-mediated translocations, suggesting the involvement of non-B DNA. Indeed, experiments using a plasmid-based model system showed that the formation of non-B DNA is likely the key to palindrome-mediated genomic rearrangements. Some evidence implies a new mechanism that cruciform DNAs may come close together first in nucleus and illegitimately joined. Analysis of PATRR-mediated translocations in humans will provide further understanding of gross chromosomal rearrangements in many organisms.

  5. Translocation of gut flora and its role in sepsis

    Directory of Open Access Journals (Sweden)

    C Vaishnavi

    2013-01-01

    Full Text Available Bacterial translocation is the invasion of indigenous intestinal bacteria through the gut mucosa to normally sterile tissues and the internal organs. Sometimes instead of bacteria, inflammatory compounds are responsible for clinical symptoms as in systemic inflammatory response syndrome (SIRS. The difference between sepsis and SIRS is that pathogenic bacteria are isolated from patients with sepsis but not with those of SIRS. Bacterial translocation occurs more frequently in patients with intestinal obstruction and in immunocompromised patients and is the cause of subsequent sepsis. Factors that can trigger bacterial translocation from the gut are host immune deficiencies and immunosuppression, disturbances in normal ecological balance of gut, mucosal barrier permeability, obstructive jaundice, stress, etc. Bacterial translocation occurs through the transcellular and the paracellular pathways and can be measured both directly by culture of mesenteric lymph nodes and indirectly by using labeled bacteria, peripheral blood culture, detection of microbial DNA or endotoxin and urinary excretion of non-metabolisable sugars. Bacterial translocation may be a normal phenomenon occurring on frequent basis in healthy individuals without any deleterious consequences. But when the immune system is challenged extensively, it breaks down and results in septic complications at different sites away from the main focus. The factors released from the gut and carried in the mesenteric lymphatics but not in the portal blood are enough to cause multi-organ failure. Thus, bacterial translocation may be a promoter of sepsis but not the initiator. This paper reviews literature on the translocation of gut flora and its role in causing sepsis.

  6. Does translocation influence physiological stress in the desert tortoise?

    Science.gov (United States)

    Drake, K.K.; Nussear, K.E.; Esque, T.C.; Barber, A.M.; Vittum, K.M.; Medica, P.A.; Tracy, C.R.; Hunter, K.W.

    2012-01-01

    Wildlife translocation is increasingly used to mitigate disturbances to animals or habitat due to human activities, yet little is known about the extent to which translocating animals causes stress. To understand the relationship between physiological stress and translocation, we conducted a multiyear study (2007–2009) using a population of desert tortoises (Gopherus agassizii) near Fort Irwin, California. Blood samples were collected from adult tortoises in three treatment groups (resident, translocated and control) for 1 year prior to and 2 years after translocation. Samples were analyzed by radioimmunoassay for plasma total corticosterone (CORT), a glucocorticoid hormone commonly associated with stress responses in reptiles. CORT values were analyzed in relation to potential covariates (animal sex, date, behavior, treatment, handling time, air temperature, home-range size, precipitation and annual plant production) among seasons and years. CORT values in males were higher than in females, and values for both varied monthly throughout the activity season and among years. Year and sex were strong predictors of CORT, and translocation explained little in terms of CORT. Based on these results, we conclude that translocation does not elicit a physiological stress response in desert tortoises.

  7. Kinetic mechanism of DNA translocation by the RSC molecular motor.

    Science.gov (United States)

    Eastlund, Allen; Malik, Shuja Shafi; Fischer, Christopher J

    2013-04-15

    ATP-dependent nucleosome repositioning by chromatin remodeling enzymes requires the translocation of these enzymes along the nucleosomal DNA. Using a fluorescence stopped-flow assay we monitored DNA translocation by a minimal RSC motor and through global analysis of these time courses we have determined that this motor has a macroscopic translocation rate of 2.9 bp/s with a step size of 1.24 bp. From the complementary quantitative analysis of the associated time courses of ATP consumption during DNA translocation we have determined that this motor has an efficiency of 3.0 ATP/bp, which is slightly less that the efficiency observed for several genetically related DNA helicases and which likely results from random pausing by the motor during translocation. Nevertheless, this motor is able to exert enough force during translocation to displace streptavidin from biotinylated DNA. Taken together these results are the necessary first step for quantifying both the role of DNA translocation in nucleosome repositioning by RSC and the efficiency at which RSC couples ATP binding and hydrolysis to nucleosome repositioning.

  8. Genetic outcomes from the translocations of the critically endangered woylie

    Institute of Scientific and Technical Information of China (English)

    Carlo PACIONI; Adrian F.WAYNE; Peter B.S.SPENCER

    2013-01-01

    Translocations are an important conservation strategy for many species.However simply observing demographic growth of a translocated population is not sufficient to infer species recovery.Adequate genetic representation of the source population(s) and their long-term viability should also be considered.The woylie Bettongiapenicillata ogilbyi has been subject to more formal translocations for conservation than any other marsupial that,up until recently,has resulted in one of the most successful species recoveries in Australia.We used mitochondrial and nuclear DNA markers to assess the genetic outcomes of translocated woylie populations.These populations have lost genetic variability,differentiated from their source population and the supplementation program on two island populations appears to have failed.We discuss the conservation implications that our results have for managing threatened species,outline some general recommendations for the management of present and future translocations and discuss the appropriate sampling design for the establishment of new populations or captive breeding programs that may mitigate the genetic ‘erosion' seen in our study species.This research provides some practical outcomes and a pmgrnatic understanding of translocation biology.The findings are directly applicable to other translocation programs.

  9. 不同变化环境背景下非平稳性洪水频率对比研究%Comparative study on non-stationary flood frequency analysis in different backgrounds of changing environment

    Institute of Scientific and Technical Information of China (English)

    叶长青; 陈晓宏; 张家鸣; 张丽娟; 朱爱萍

    2014-01-01

    世界上众多江河洪水序列形成的环境背景“一致性”已不复存在,传统极值流量分析的“极值理论”须要修正以适应这些现象.采用时间变化矩模型对武江坪石站和东江龙川站年最大日流量序列进行非平稳性处理,选择5种分布线型、8种趋势模型共40种模型进行比较.结果表明,坪石站对数正态分布(LN2)搭配均值和标准差相关且具有线性趋势模型(CL)拟合最好;龙川站LN2分布搭配均值和标准差相关且具有抛物线趋势模型(CP)拟合效果最优.对同一设计标准P,洪水设计值均随时间存在显著变化关系.坪石站在气候与植被下降后非平稳性洪水设计值随时间由小增大;而龙川站受气候与人类活动影响特别是水库调蓄后洪水设计值随时间由大变小.非平稳性背景下,传统洪水重现期概念应该被修正.%No "stationarity" exists any longer in environmental backgrounds for the formation of flood series of various rivers in the world,and traditional extreme value flow analysis,i.e.extreme value theory must be amended to adapt to these phenomena.This study adopted a non-stationary processing method of time-varying moments to analyze and calculate the annual maximum daily flow series at the Pingshi station of Wujiang River and the Longchuan stations of East River,using five types of distribution curves and eight kinds of trend models,i.e.totally 40 models for comparison.The results show that best fitting occurs in two combinations:two-parameter lognormal (LN2) distribution with a CL model at Pingshi (mean and standard deviation have linear trends and are related by a constant),and LN2 distribution with a CP model at Longchuan (mean and standard deviation have parabolic trends and are related by a constant).At the same flood design standard P,the design value alters over time significantly.At Pingshi the design value of non-stationary flood series changes from low to high over time in the

  10. The 2NS Translocation from Aegilops ventricosa Confers Resistance to the Triticum Pathotype of Magnaporthe oryzae

    Science.gov (United States)

    Cruz, C.D.; Peterson, G.L.; Bockus, W.W.; Kankanala, P.; Dubcovsky, J.; Jordan, K.W.; Akhunov, E.; Chumley, F.; Baldelomar, F.D.; Valent, B.

    2016-01-01

    Wheat blast is a serious disease caused by the fungus Magnaporthe oryzae (Triticum pathotype) (MoT). The objective of this study was to determine the effect of the 2NS translocation from Aegilops ventricosa (Zhuk.) Chennav on wheat head and leaf blast resistance. Disease phenotyping experiments were conducted in growth chamber, greenhouse, and field environments. Among 418 cultivars of wheat (Triticum aestivum L.), those with 2NS had 50.4 to 72.3% less head blast than those without 2NS when inoculated with an older MoT isolate under growth chamber conditions. When inoculated with recently collected isolates, cultivars with 2NS had 64.0 to 80.5% less head blast. Under greenhouse conditions when lines were inoculated with an older MoT isolate, those with 2NS had a significant head blast reduction. With newer isolates, not all lines with 2NS showed a significant reduction in head blast, suggesting that the genetic background and/or environment may influence the expression of any resistance conferred by 2NS. However, when near-isogenic lines (NILs) with and without 2NS were planted in the field, there was strong evidence that 2NS conferred resistance to head blast. Results from foliar inoculations suggest that the resistance to head infection that is imparted by the 2NS translocation does not confer resistance to foliar disease. In conclusion, the 2NS translocation was associated with significant reductions in head blast in both spring and winter wheat.

  11. Observing GLUT4 Translocation in Live L6 Cells Using Quantum Dots

    Directory of Open Access Journals (Sweden)

    Feng Qu

    2011-02-01

    Full Text Available The glucose transporter 4 (GLUT4 plays a key role in maintaining whole body glucose homeostasis. Tracking GLUT4 in space and time can provide new insights for understanding the mechanisms of insulin-regulated GLUT4 translocation. Organic dyes and fluorescent proteins were used in previous studies for investigating the traffic of GLUT4 in skeletal muscle cells and adipocytes. Because of their relative weak fluorescent signal against strong cellular autofluorescence background and their fast photobleaching rate, most studies only focused on particular segments of GLUT4 traffic. In this study, we have developed a new method for observing the translocation of GLUT4 targeted with photostable and bright quantum dots (QDs in live L6 cells. QDs were targeted to GLUT4myc specifically and internalized with GLUT4myc through receptor-mediated endocytosis. Compared with traditional fluorescence dyes and fluorescent proteins, QDs with high brightness and extremely photostability are suitable for long-term single particle tracking, so individual GLUT4-QD complex can be easily detected and tracked for long periods of time. This newly described method will be a powerful tool for observing the translocation of GLUT4 in live L6 cells.

  12. Translocation of threatened plants as a conservation measure in China.

    Science.gov (United States)

    Liu, Hong; Ren, Hai; Liu, Qiang; Wen, XiangYing; Maunder, Michael; Gao, JiangYun

    2015-12-01

    We assessed the current status of plant conservation translocation efforts in China, a topic poorly reported in recent scientific literature. We identified 222 conservation translocation cases involving 154 species, of these 87 were Chinese endemic species and 101 (78%) were listed as threatened on the Chinese Species Red List. We categorized the life form of each species and, when possible, determined for each case the translocation type, propagule source, propagule type, and survival and reproductive parameters. A surprisingly large proportion (26%) of the conservation translocations in China were conservation introductions, largely implemented in response to large-scale habitat destruction caused by the Three-Gorge Dam and another hydropower project. Documentation and management of the translocations varied greatly. Less than half the cases had plant survival records. Statistical analyses showed that survival percentages were significantly correlated with plant life form and the type of planting materials. Thirty percent of the cases had records on whether or not individuals flowered or fruited. Results of information theoretic model selection indicated that plant life form, translocation type, propagule type, propagule source, and time since planting significantly influenced the likelihood of flowering and fruiting on the project level. We suggest that the scientific-based application of species conservation translocations should be promoted as part of a commitment to species recovery management. In addition, we recommend that the common practice of within and out of range introductions in nature reserves to be regulated more carefully due to its potential ecological risks. We recommend the establishment of a national office and database to coordinate conservation translocations in China. Our review effort is timely considering the need for a comprehensive national guideline for the newly announced nation-wide conservation program on species with extremely

  13. Supersymmetric heterotic string backgrounds

    NARCIS (Netherlands)

    Gran, U.; Papadopoulos, G.; Roest, D.; Cvetič, M.

    2007-01-01

    We present the main features of the solution of the gravitino and dilatino Killing spinor equations derived in hep-th/0510176 and hep-th/0703143 which have led to the classification of geometric types of all type I backgrounds. We then apply these results to the supersymmetric backgrounds of the het

  14. The Cosmic Microwave Background

    OpenAIRE

    Silk, Joseph

    2002-01-01

    This set of lectures provides an overview of the basic theory and phenomenology of the cosmic microwave background. Topics include a brief historical review; the physics of temperature and polarization fluctuations; acoustic oscillations of the primordial plasma; the space of inflationary cosmological models; current and potential constraints on these models from the microwave background; and constraints on inflation.

  15. [Mechanisms of bacteria translocation in generalized chronic parodontitis].

    Science.gov (United States)

    Bukharin, O V; Usviatsov, B Ia; Doroshina, N B; Kushkinbaeva, D R; Khlopko, Iu A

    2011-01-01

    Peculiarities of behavior reactions of bacteria-symbionts created conditions for the selection of translocators-strains. In microsymbiocenosis of parodontal pockets, from which translocation of bacteria into the blood was observed, the number of signals from intermicrobial communication, inhibiting the expression of the factors of colonization, virulence and persistence, was decreasing. Meanwhile, the number of signals on the increase of the expression of the factors given was increased. In 75% of cases strains-translocators were leaders; they gave more often signals on the inhibition of the growth of other strains-symbionts.

  16. The Athena Background

    Science.gov (United States)

    Piro, Luigi; Lotti, Simone; Macculi, Claudio; Molendi, Silvano; Eraerds, Tanja; Laurent, Philippe

    2015-09-01

    Estimating, reducing and controlling the residual particle background is fundamental for achieving the objectives of several science topics of Athena, in particular those connected with background dominated observations of faint and/or diffuse sources. This requires assessing the particle environment in L2, propagating the various particle components throughout the mirror, spacecraft, and instruments via proper modelling and simulations of various physical processes, implementing design and h/w measures at instrument and mission level to reduce the un-rejected background and identifying proper calibration methods to control the background variations. Likewise, an adequate knowledge of the XRB, made of components that may vary spatially or temporally, is required as well. Here we will review the present status of the background knowledge, and summarize the activities on-going within Athena at various levels.

  17. Bacterial translocation - impact on the adipocyte compartment.

    Science.gov (United States)

    Kruis, Tassilo; Batra, Arvind; Siegmund, Britta

    2014-01-01

    Over the last decade it became broadly recognized that adipokines and thus the fat tissue compartment exert a regulatory function on the immune system. Our own group described the pro-inflammatory function of the adipokine leptin within intestinal inflammation in a variety of animal models. Following-up on this initial work, the aim was to reveal stimuli and mechanisms involved in the activation of the fat tissue compartment and the subsequent release of adipokines and other mediators paralleled by the infiltration of immune cells. This review will summarize the current literature on the possible role of the mesenteric fat tissue in intestinal inflammation with a focus on Crohn's disease (CD). CD is of particular interest in this context since the transmural intestinal inflammation has been associated with a characteristic hypertrophy of the mesenteric fat, a phenomenon called "creeping fat." The review will address three consecutive questions: (i) What is inducing adipocyte activation, (ii) which factors are released after activation and what are the consequences for the local fat tissue compartment and infiltrating cells; (iii) do the answers generated before allow for an explanation of the role of the mesenteric fat tissue within intestinal inflammation? With this review we will provide a working model indicating a close interaction in between bacterial translocation, activation of the adipocytes, and subsequent direction of the infiltrating immune cells. In summary, the models system mesenteric fat indicates a unique way how adipocytes can directly interact with the immune system.

  18. Energy-dependent intracellular translocation of proparathormone.

    Science.gov (United States)

    Chu, L L; MacGregor, R R; Cohn, D V

    1977-01-01

    We previously suggested that after synthesis, proparathormone is transferred from rough endoplasmic reticulum to the Golgi region where its conversion to parathormone occurs. We have attempted to define more closely this transfer process. In the first type of study, bovine parathyroid slices were incubated with [3H]leucine for 10 min and then radioisotope labeling was restricted by addition of a large excess of nonradioactive leucine. Under these conditions, more than 90% of the initially labeled proparathormone was converted to parathormone in 40 min. Lowered temperature in the chase period markedly inhibited the conversion. Several chemical agents were employed individually in the chase period to examine their effect on the conversion process. Antimycin A, dinitrophenol, oligomycin, and anaerobiosis (N2) inhibited the conversion, whereas sodium flouride and cycloheximide had no effect. In the second type of study, parathyroid slices were incubated with [3H]leucine for the entire incubation period. Lowered temperature and inhibitors of energy metabolism and microtubular function all lengthened the interval (lag) between the initial synthesis of [3H]parathormone. Cycloheximide, Tris, and chloroquine decreased the rates of protein synthesis and conversion, respectively, but none had any effect on the lag. We interpret the lag to represent the time of transit for proparathormone from rough endoplasmic reticulum to the Golgi region. We conclude that this transfer process is independent of the synthesis of the prohormone and its conversion to the hormone. Moreover, this translocation requires metabolic energy and appears to be mediated by microtubules.

  19. Chromosome segregation analysis in human embryos obtained from couples involving male carriers of reciprocal or Robertsonian translocation.

    Directory of Open Access Journals (Sweden)

    Ahmet Yilmaz

    Full Text Available The objective of this study was to investigate the frequency and type of chromosome segregation patterns in cleavage stage embryos obtained from male carriers of Robertsonian (ROB and reciprocal (REC translocations undergoing preimplantation genetic diagnosis (PGD at our reproductive center. We used FISH to analyze chromosome segregation in 308 day 3 cleavage stage embryos obtained from 26 patients. The percentage of embryos consistent with normal or balanced segregation (55.1% vs. 27.1% and clinical pregnancy (62.5% vs. 19.2% rates were higher in ROB than the REC translocation carriers. Involvement of non-acrocentric chromosome(s or terminal breakpoint(s in reciprocal translocations was associated with an increase in the percent of embryos consistent with adjacent 1 but with a decrease in 3∶1 segregation. Similar results were obtained in the analysis of nontransferred embryos donated for research. 3∶1 segregation was the most frequent segregation type in both day 3 (31% and spare (35% embryos obtained from carriers of t(11;22(q23;q11, the only non-random REC with the same breakpoint reported in a large number of unrelated families mainly identified by the birth of a child with derivative chromosome 22. These results suggest that chromosome segregation patterns in day 3 and nontransferred embryos obtained from male translocation carriers vary with the type of translocation and involvement of acrocentric chromosome(s or terminal breakpoint(s. These results should be helpful in estimating reproductive success in translocation carriers undergoing PGD.

  20. De Novo microdeletion on an inherited Robertsonian translocation chromosome: A cause for dysmorphism in the apparently balanced translocation carrier

    Energy Technology Data Exchange (ETDEWEB)

    Bonthron, D.T.; Smith, S.J.L.; Fantes, J.; Gosden, C.M.

    1993-09-01

    Robertsonian translocations are usually ascertained through abnormal children, making proposed phenotypic effects of apparently balanced translocations difficult to study in an unbiased way. From molecular genetic studies, though, some apparently balanced rearrangments are now known to be associated with phenotypic abnormalities resulting from uniparental disomy. Molecular explanations for other cases in which abnormality is seen in a balanced translocation carrier are being sought. In the present paper, an infant is described who has retarded growth, developmental delay, gross muscular hypotonia, slender habitus, frontal bossing, micrognathia, hooked nose, abundant wispy hair, and blue sclerae. Cytogenetically, she appeared to be a carrier of a balanced, paternally derived 14;21 Robertsonian translocation. Analysis of DNA polymorphisms showed that she had no paternal allele at the D14S13 locus (14q32). Study of additional DNA markers within 14q32 revealed that her previously undescribed phenotype results from an interstitial microdeletion within 14q32. Fluorescent in situ hybridization was used to show that this microdeletion had occurred de novo on the Robertsonian translocation chromosome. These observations may reactivate old suspicions of a causal association between Robertsonian translocations and de novo rearrangements in offspring; a systematic search for similar subcytogentic rearrangements in other families, in which there are phenotypically abnormal children with apparently balanced translocations, may be fruitful. The clinical and molecular genetic data presented also define a new contiguous gene syndrome due to interstitial 14q32 deletion. 42 refs., 4 figs., 1 tab.

  1. Gut microbiota dysbiosis is associated with inflammation and bacterial translocation in mice with CCl4-induced fibrosis.

    Directory of Open Access Journals (Sweden)

    Isabel Gómez-Hurtado

    Full Text Available BACKGROUND: Gut is the major source of endogenous bacteria causing infections in advanced cirrhosis. Intestinal barrier dysfunction has been described in cirrhosis and account for an increased bacterial translocation rate. HYPOTHESIS AND AIMS: We hypothesize that microbiota composition may be affected and change along with the induction of experimental cirrhosis, affecting the inflammatory response. ANIMALS AND METHODS: Progressive liver damage was induced in Balb/c mice by weight-controlled oral administration of carbon tetrachloride. Laparotomies were performed at weeks 6, 10, 13 and 16 in a subgroup of treated mice (n = 6/week and control animals (n = 4/week. Liver tissue specimens, mesenteric lymph nodes, intestinal content and blood were collected at laparotomies. Fibrosis grade, pro-fibrogenic genes expression, gut bacterial composition, bacterial translocation, host's specific butyrate-receptor GPR-43 and serum cytokine levels were measured. RESULTS: Expression of pro-fibrogenic markers was significantly increased compared with control animals and correlated with the accumulated dose of carbon tetrachloride. Bacterial translocation episodes were less frequent in control mice than in treated animals. Gram-positive anaerobic Clostridia spp count was decreased in treated mice compared with control animals and with other gut common bacterial species, altering the aerobic/anaerobic ratio. This fact was associated with a decreased gene expression of GPR43 in neutrophils of treated mice and inversely correlated with TNF-alpha and IL-6 up-regulation in serum of treated mice along the study protocol. This pro-inflammatory scenario favoured blood bacterial translocation in treated animals, showing the highest bacterial translocation rate and aerobic/anaerobic ratio at the same weeks. CONCLUSIONS: Gut microbiota alterations are associated with the development of an inflammatory environment, fibrosis progression and bacterial translocation in

  2. A novel missense adenine nucleotide translocator-1 gene mutation in a Greek adPEO family.

    Science.gov (United States)

    Napoli, L; Bordoni, A; Zeviani, M; Hadjigeorgiou, G M; Sciacco, M; Tiranti, V; Terentiou, A; Moggio, M; Papadimitriou, A; Scarlato, G; Comi, G P

    2001-12-26

    Autosomal dominant progressive external ophthalmoplegia (adPEO) is caused by mutations in at least three different genes: ANT1 (chromosome 4q34-35), TWINKLE, and POLG. The ANT1 gene encodes the adenine nucleotide translocator-1 (ANT1). We identified a heterozygous T293C mutation of the ANT1 gene in a Greek family with adPEO. The resulting leucine to proline substitution likely modifies the secondary structure of the ANT1 protein. ANT1 gene mutations may account for adPEO in families with different ethnic backgrounds.

  3. DNA-graphene interactions during translocation through nanogaps

    Science.gov (United States)

    Patel, Hiral N.; Carroll, Ian; Lopez, Rodolfo; Sankararaman, Sandeep; Etienne, Charles; Kodigala, Subba Ramaiah; Paul, Mark R.

    2017-01-01

    We study how double-stranded DNA translocates through graphene nanogaps. Nanogaps are fabricated with a novel capillary-force induced graphene nanogap formation technique. DNA translocation signatures for nanogaps are qualitatively different from those obtained with circular nanopores, owing to the distinct shape of the gaps discussed here. Translocation time and conductance values vary by ∼ 100%, which we suggest are caused by local gap width variations. We also observe exponentially relaxing current traces. We suggest that slow relaxation of the graphene membrane following DNA translocation may be responsible. We conclude that DNA-graphene interactions are important, and need to be considered for graphene-nanogap based devices. This work further opens up new avenues for direct read of single molecule activitities, and possibly sequencing. PMID:28158244

  4. Fragility in the 14q21q translocation region

    Directory of Open Access Journals (Sweden)

    Stacy R. Denison

    2002-01-01

    Full Text Available Aphidicolin (APC-induced chromosomal breakage was analyzed for women representing three generations of a single family and carrying a Robertsonian translocation rob(14q21q. Fluorescence in situ hybridization (FISH analysis confirmed the dicentric constitution of the derived chromosome and indicated the absence of beta-satellite signal at the translocation region. Per-individual analysis of metaphases from APC-treated peripheral blood lymphocyte cultures identified significantly nonrandom chromosomal breakage at the translocation region in all three individuals examined. The APC-inducible fragility at the 14q21q translocation region suggests that this rearrangement was the result of chromosomal mutation at fragile site(s in the progenitor chromosomes, or that this fragility was the result of the fusion of nonfragile progenitor chromosomes.

  5. DNA translocations through solid-state plasmonic nanopores.

    Science.gov (United States)

    Nicoli, Francesca; Verschueren, Daniel; Klein, Misha; Dekker, Cees; Jonsson, Magnus P

    2014-12-10

    Nanopores enable label-free detection and analysis of single biomolecules. Here, we investigate DNA translocations through a novel type of plasmonic nanopore based on a gold bowtie nanoantenna with a solid-state nanopore at the plasmonic hot spot. Plasmonic excitation of the nanopore is found to influence both the sensor signal (nanopore ionic conductance blockade during DNA translocation) and the process that captures DNA into the nanopore, without affecting the duration time of the translocations. Most striking is a strong plasmon-induced enhancement of the rate of DNA translocation events in lithium chloride (LiCl, already 10-fold enhancement at a few mW of laser power). This provides a means to utilize the excellent spatiotemporal resolution of DNA interrogations with nanopores in LiCl buffers, which is known to suffer from low event rates. We propose a mechanism based on plasmon-induced local heating and thermophoresis as explanation of our observations.

  6. TRANSLOCATION OF BACTERIA AND ENDOTOXIN IN ORGAN DONORS

    NARCIS (Netherlands)

    van Goor, Harry; Rosman, C; Kooi, K; Wubbels, GH; Bleichrodt, RP

    1994-01-01

    Objective: To determine if bacterial translocation and endotoxin absorption occur in organ donors with an anatomically intact gastrointestinal tract. Design: Case series. Setting: Intensive care units in general and university hospitals. Patients: Twenty-one (multiple) organ donors. Intervention: No

  7. Influence of Methylobacterium on iron translocation in plants.

    Science.gov (United States)

    Bishop, Yvonne M; Barton, Larry L; Johnson, Gordon V

    2011-06-01

    Iron metabolism in plants is essential to maintain optimal growth and iron nutrition is dependent on uptake of iron from the environment and movement of iron in the plant tissues. We have examined the translocation of iron in plant leaves following foliar application of FeEDTA to Vicia faba and Zea mays. Using radiolabeled iron, we observed that iron translocation is stimulated by products of Methylobacterium mesophylicum and by the cytokinin, kinetin. When cytokinins were applied to leaves along with (55)FeEDTA, the rate of iron translocation was greater than in controls without cytokinin addition. Since recent studies indicate that M. mesophylicum is widely distributed in the environment as a pyllospheric bacterium, this organism may have an important role in enhancing translocation of nutrients in plant leaves.

  8. Effects of granulocyte-colony stimulating factor on peritoneal defense mechanisms and bacterial translocation after administration of systemic chemotherapy in rats

    Institute of Scientific and Technical Information of China (English)

    Celal Cerci; Cagri Ergin; Erol Eroglu; Canan Agalar; Fatih Agalar; Sureyya Cerci; Mahmut Bulbul

    2007-01-01

    AIM: To investigate the effects of granulocyte-colony stimulating factor (G-CSF) on peritoneal defense mechanisms and bacterial translocation after systemic 5-Fluorouracil (5-FU) administration.METHODS: Thirty Wistar albino rats were divided into three groups; the control, 5-FU and 5-FU + G-CSF groups. We measured bactericidal activity of the peritoneal fluid, phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid, total peritoneal cell counts and cell types of peritoneal washing fluid.Bacterial translocation was quantified by mesenteric lymph node, liver and spleen tissue cultures.RESULTS: Systemic 5-FU reduced total peritoneal cell counts, neutrophils and macrophage numbers. It also altered bactericidal activity of the peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid. 5-FU also caused significant increase in frequencies of bacterial translocation at the liver and mesenteric lymph nodes. G-CSF decreased bacterial translocation, it significantly enhanced bactericidal activity of the peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid. It also increased total peritoneal cell counts, neutrophils and macrophage numbers.CONCLUSION: Systemic 5-FU administration caused bacterial translocation, decreased the bactericidal activity of peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid. G-CSF increased both bactericidal activity of the peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid, and prevented the bacterial translocation. We conclude that intraperitoneal GCSF administration protects the effects of systemic 5-FU on peritoneal defense mechanisms.

  9. Cosmogenic Backgrounds to 0{\

    CERN Document Server

    :,; Auty, D J; Barbeau, P S; Beck, D; Belov, V; Breidenbach, M; Brunner, T; Burenkov, A; Cao, G F; Chambers, C; Cleveland, B; Coon, M; Craycraft, A; Daniels, T; Danilov, M; Daugherty, S J; Davis, J; Delaquis, S; Der Mesrobian-Kabakian, A; DeVoe, R; Didberidze, T; Dilling, J; Dolgolenko, A; Dolinski, M J; Dunford, M; Fairbank, W; Farine, J; Feldmeier, W; Feyzbakhsh, S; Fierlinger, P; Fudenberg, D; Gornea, R; Graham, K; Gratta, G; Hall, C; Herrin, S; Hughes, M; Jewell, M J; Johnson, A; Johnson, T N; Johnston, S; Karelin, A; Kaufman, L J; Killick, R; Koffas, T; Kravitz, S; Krücken, R; Kuchenkov, A; Kumar, K S; Leonard, D S; Licciardi, C; Lin, Y H; Ling, J; MacLellan, R; Marino, M G; Mong, B; Moore, D; Njoya, O; Nelson, R; Odian, A; Ostrovskiy, I; Piepke, A; Pocar, A; Prescott, C Y; Retière, F; Rowson, P C; Russell, J J; Schubert, A; Sinclair, D; Smith, E; Stekhanov, V; Tarka, M; Tolba, T; Tsang, R; Twelker, K; Vuilleumier, J -L; Waite, A; Walton, J; Walton, T; Weber, M; Wen, L J; Wichoski, U; Wood, J; Yang, L; Yen, Y -R; Zeldovich, O Ya

    2015-01-01

    As neutrinoless double-beta decay experiments become more sensitive and intrinsic radioactivity in detector materials is reduced, previously minor contributions to the background must be understood and eliminated. With this in mind, cosmogenic backgrounds have been studied with the EXO-200 experiment. Using the EXO-200 TPC, the muon flux (through a flat horizontal surface) underground at the Waste Isolation Pilot Plant (WIPP) has been measured to be {\\Phi} = 4.07 $\\pm$ 0.14 (sys) $\\pm$ 0.03 (stat) $\\times$ $10^{-7}$cm$^{-2}$ s$^{-1}$, with a vertical intensity of $I_{v}$ = 2.97$^{+0.14}_{-0.13}$ (sys) $\\pm$ 0.02 (stat) $\\times$ $10^{-7}$cm$^{-2}$ s$^{-1}$ sr$^{-1}$. Simulations of muon-induced backgrounds identified several potential cosmogenic radionuclides, though only 137Xe is a significant background for the 136Xe 0{\

  10. Zambia Country Background Report

    DEFF Research Database (Denmark)

    Hampwaye, Godfrey; Jeppesen, Søren; Kragelund, Peter

    This paper provides background data and general information for the Zambia studies focusing on local food processing sub­‐sector; and the local suppliers to the mines as part of the SAFIC project (Successful African Firms and Institutional Change).......This paper provides background data and general information for the Zambia studies focusing on local food processing sub­‐sector; and the local suppliers to the mines as part of the SAFIC project (Successful African Firms and Institutional Change)....

  11. Slowing DNA Translocation in a Nanofluidic Field-Effect Transistor.

    Science.gov (United States)

    Liu, Yifan; Yobas, Levent

    2016-04-26

    Here, we present an experimental demonstration of slowing DNA translocation across a nanochannel by modulating the channel surface charge through an externally applied gate bias. The experiments were performed on a nanofluidic field-effect transistor, which is a monolithic integrated platform featuring a 50 nm-diameter in-plane alumina nanocapillary whose entire length is surrounded by a gate electrode. The field-effect transistor behavior was validated on the gating of ionic conductance and protein transport. The gating of DNA translocation was subsequently studied by measuring discrete current dips associated with single λ-DNA translocation events under a source-to-drain bias of 1 V. The translocation speeds under various gate bias conditions were extracted by fitting event histograms of the measured translocation time to the first passage time distributions obtained from a simple 1D biased diffusion model. A positive gate bias was observed to slow the translocation of single λ-DNA chains markedly; the translocation speed was reduced by an order of magnitude from 18.4 mm/s obtained under a floating gate down to 1.33 mm/s under a positive gate bias of 9 V. Therefore, a dynamic and flexible regulation of the DNA translocation speed, which is vital for single-molecule sequencing, can be achieved on this device by simply tuning the gate bias. The device is realized in a conventional semiconductor microfabrication process without the requirement of advanced lithography, and can be potentially further developed into a compact electronic single-molecule sequencer.

  12. Survival of mountain quail translocated from two distinct source populations

    Science.gov (United States)

    Troy, Ronald J.; Coates, Peter S.; Connelly, John W.; Gillette, Gifford; Delehanty, David J.

    2013-01-01

    Translocation of mountain quail (Oreortyx pictus) to restore viable populations to their former range has become a common practice. Because differences in post-release vital rates between animals from multiple source populations has not been well studied, wildlife and land managers may arbitrarily choose the source population or base the source population on immediate availability when planning translocation projects. Similarly, an understanding of the optimal proportion of individuals from different age and sex classes for translocation would benefit translocation planning. During 2006 and 2007, we captured and translocated 125 mountain quail from 2 ecologically distinct areas: 38 from southern California and 87 from southwestern Oregon. We released mountain quail in the Bennett Hills of south-central Idaho. We radio-marked and monitored a subsample of 58 quail and used them for a 2-part survival analysis. Cumulative survival probability was 0.23 ± 0.05 (SE) at 150 days post-release. We first examined an a priori hypothesis (model) that survival varied between the 2 distinct source populations. We found that source population did not explain variation in survival. This result suggests that wildlife managers have flexibility in selecting source populations for mountain quail translocation efforts. In a post hoc examination, we pooled the quail across source populations and evaluated differences in survival probabilities between sex and age classes. The most parsimonious model indicated that adult male survival was substantially less than survival rates of other mountain quail age and sex classes (i.e., interaction between sex and age). This result suggests that translocation success could benefit by translocating yearling males rather than adult males, perhaps because adult male breeding behavior results in vulnerability to predators

  13. Atomic structure of anthrax protective antigen pore elucidates toxin translocation.

    Science.gov (United States)

    Jiang, Jiansen; Pentelute, Bradley L; Collier, R John; Zhou, Z Hong

    2015-05-28

    Anthrax toxin, comprising protective antigen, lethal factor, and oedema factor, is the major virulence factor of Bacillus anthracis, an agent that causes high mortality in humans and animals. Protective antigen forms oligomeric prepores that undergo conversion to membrane-spanning pores by endosomal acidification, and these pores translocate the enzymes lethal factor and oedema factor into the cytosol of target cells. Protective antigen is not only a vaccine component and therapeutic target for anthrax infections but also an excellent model system for understanding the mechanism of protein translocation. On the basis of biochemical and electrophysiological results, researchers have proposed that a phi (Φ)-clamp composed of phenylalanine (Phe)427 residues of protective antigen catalyses protein translocation via a charge-state-dependent Brownian ratchet. Although atomic structures of protective antigen prepores are available, how protective antigen senses low pH, converts to active pore, and translocates lethal factor and oedema factor are not well defined without an atomic model of its pore. Here, by cryo-electron microscopy with direct electron counting, we determine the protective antigen pore structure at 2.9-Å resolution. The structure reveals the long-sought-after catalytic Φ-clamp and the membrane-spanning translocation channel, and supports the Brownian ratchet model for protein translocation. Comparisons of four structures reveal conformational changes in prepore to pore conversion that support a multi-step mechanism by which low pH is sensed and the membrane-spanning channel is formed.

  14. Surface modification of graphene nanopores for protein translocation

    Science.gov (United States)

    Shan, Y. P.; Tiwari, P. B.; Krishnakumar, P.; Vlassiouk, I.; Li, W.Z.; Wang, X.W.; Darici, Y.; Lindsay, S.M.; Wang, H. D.; Smirnov, S.; He, J.

    2014-01-01

    Studies of DNA translocation through graphene nanopores have revealed their potential for DNA sequencing. Here we report a study of protein translocation through chemically modified graphene nanopores. A transmission electron microscope (TEM) was used to cut nanopores with diameters between 5-20 nm in multilayer graphene prepared by chemical vapor deposition (CVD). After oxygen plasma treatment, the dependence of the measured ionic current on salt concentration and pH was consistent with a small surface charge induced by the formation of carboxyl groups. While translocation of gold nanoparticles (10 nm) was readily detected through such treated pores of a larger diameter, translocation of protein ferritin was not observed either for oxygen plasma treated pores, or for pores modified with mercaptohexadecanoic acid. Ferritin translocation events were reliably observed after the pores were modified with the phospholipid-PEG (DPPE-PEG750) amphiphile. The ion current signature of translocation events was complex, suggesting that a series of interactions between the protein and pore occur during the process. PMID:24231385

  15. Uptake, translocation, and debromination of polybrominated diphenyl ethers in maize

    Institute of Scientific and Technical Information of China (English)

    Moming Zhao; Shuzhen Zhang; Sen Wang; Honglin Huang

    2012-01-01

    Uptake,translocation and debromination of three polybrominated diphenyl ethers(PBDEs),BDE-28,-47 and-99,in maize were studied in a hydroponic experiment.Roots took up most of the PBDEs in the culture solutions and more highly brominated PBDEs had a stronger uptake capability.PBDEs were detected in the stems and leaves of maize after exposure but rarely detected in the blank control plants.Furthermore,PBDE concentrations decreased from roots to stems and then to leaves,and a very clear decreasing gradient was found in segments upwards along the stem.These altogether provide substantiating evidence for the acropetal translocation of PBDEs in maize.More highly brominated PBDEs were translocated with more difficulty.Radial translocation of PBDEs from nodes to sheath inside maize was also observed.Both acropetal and radial translocations were enhanced at higher transpiration rates,suggesting that PBDE transport was probably driven by the transpiration stream.Debromination of PBDEs occurred in all parts of the maize,and debromination patterns of different parent PBDEs and in different parts of a plant were similar but with some differences.This study for the first time provides direct evidence for the acropetal translocation of PBDEs within plants,elucidates the process of PBDE transport and clarifies the debromination products of PBDEs in maize.

  16. A rare Robertsonian translocation rob(14;22) carrier with azoospermia, meiotic defects, and testicular sperm aneuploidy.

    Science.gov (United States)

    Sobotka, Vladimir; Vozdova, Miluse; Heracek, Jiri; Rubes, Jiri

    2015-01-01

    Male infertility is a serious problem in an increasing number of couples. We report an infertile man with non-obstructive azoospermia and karyotype 45,XY,rob(14;22). The immunofluorescence analysis of his testicular tissue using antibodies to SYCP1, SYCP3, HORMAD2, MLH1, and centromeres showed delayed synapsis of the chromosomes involved in the translocation, a varying extent of trivalent asynapsis and its association with sex chromosomes. The mean frequency of meiotic recombination per cell was within the range of normal values. Fluorescence in situ hybridization (FISH) with probes for chromosomes 14 and 22 revealed 5.83% of chromosomally abnormal testicular spermatozoa. FISH with probes for chromosomes X, Y, and 21 showed frequencies of disomic and diploid testicular spermatozoa increased when compared to ejaculated sperm of healthy donors, but comparable with published results for azoospermic patients. PGD by FISH for the translocation and aneuploidy of chromosomes X, Y, 13, 18, and 21 showed a normal chromosomal complement in one out of three analyzed embryos. A healthy carrier girl was born after the embryo transfer. This study shows the benefits of preimplantation genetic diagnosis in a case of a rare Robertsonian translocation carrier with azoospermia and a relatively low frequency of chromosomally unbalanced testicular spermatozoa.

  17. Conflict bear translocation: investigating population genetics and fate of bear translocation in Dachigam National Park, Jammu and Kashmir, India.

    Science.gov (United States)

    Mukesh; Sharma, Lalit Kumar; Charoo, Samina Amin; Sathyakumar, Sambandam

    2015-01-01

    The Asiatic black bear population in Dachigam landscape, Jammu and Kashmir is well recognized as one of the highest density bear populations in India. Increasing incidences of bear-human interactions and the resultant retaliatory killings by locals have become a serious threat to the survivorship of black bears in the Dachigam landscape. The Department of Wildlife Protection in Jammu and Kashmir has been translocating bears involved in conflicts, henceforth 'conflict bears' from different sites in Dachigam landscape to Dachigam National Park as a flagship activity to mitigate conflicts. We undertook this study to investigate the population genetics and the fate of bear translocation in Dachigam National Park. We identified 109 unique genotypes in an area of ca. 650 km2 and observed bear population under panmixia that showed sound genetic variability. Molecular tracking of translocated bears revealed that mostly bears (7 out of 11 bears) returned to their capture sites, possibly due to homing instincts or habituation to the high quality food available in agricultural croplands and orchards, while only four bears remained in Dachigam National Park after translocation. Results indicated that translocation success was most likely to be season dependent as bears translocated during spring and late autumn returned to their capture sites, perhaps due to the scarcity of food inside Dachigam National Park while bears translocated in summer remained in Dachigam National Park due to availability of surplus food resources. Thus, the current management practices of translocating conflict bears, without taking into account spatio-temporal variability of food resources in Dachigam landscape seemed to be ineffective in mitigating conflicts on a long-term basis. However, the study highlighted the importance of molecular tracking of bears to understand their movement patterns and socio-biology in tough terrains like Dachigam landscape.

  18. Resonant activation in polymer translocation: new insights into the escape dynamics of molecules driven by an oscillating field.

    Science.gov (United States)

    Pizzolato, N; Fiasconaro, A; Adorno, D Persano; Spagnolo, B

    2010-08-04

    The translocation of molecules across cellular membranes or through synthetic nanopores is strongly affected by thermal fluctuations. In this work we study how the dynamics of a polymer in a noisy environment changes when the translocation process is driven by an oscillating electric field. An improved version of the Rouse model for a flexible polymer has been adopted to mimic the molecular dynamics, by taking into account the harmonic interactions between adjacent monomers and the excluded-volume effect by introducing a Lennard-Jones potential between all beads. A bending recoil torque has also been included in our model. The polymer dynamics is simulated in a two-dimensional domain by numerically solving the Langevin equations of motion. Thermal fluctuations are taken into account by introducing a Gaussian uncorrelated noise. The mean first translocation time of the polymer centre of inertia shows a minimum as a function of the frequency of the oscillating forcing field. This finding represents the first evidence of the resonant activation behaviour in the dynamics of polymer translocation.

  19. Haploinsufficiency of activation-induced deaminase for antibody diversification and chromosome translocations both in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Isora V Sernández

    Full Text Available The humoral immune response critically relies on the secondary diversification of antibodies. This diversification takes places through somatic remodelling of the antibody genes by two molecular mechanisms, Class Switch Recombination (CSR and Somatic Hypermutation (SHM. The enzyme Activation Induced Cytidine Deaminase (AID initiates both SHM and CSR by deaminating cytosine residues on the DNA of immunoglobulin genes. While crucial for immunity, AID-catalysed deamination is also the triggering event for the generation of lymphomagenic chromosome translocations. To address whether restricting the levels of AID expression in vivo contributes to the regulation of its function, we analysed mice harbouring a single copy of the AID gene (AID(+/-. AID(+/- mice express roughly 50% of normal AID levels, and display a mild hyperplasia, reminiscent of AID deficient mice and humans. Moreover, we found that AID(+/- cells have an impaired competence for CSR and SHM, which indicates that AID gene dose is limiting for its physiologic function. We next evaluated the impact of AID reduction in AID(+/- mice on the generation of chromosome translocations. Our results show that the frequency of AID-promoted c-myc/IgH translocations is reduced in AID(+/- mice, both in vivo and in vitro. Therefore, AID is haploinsufficient for antibody diversification and chromosome translocations. These findings suggest that limiting the physiologic levels of AID expression can be a regulatory mechanism that ensures an optimal balance between immune proficiency and genome integrity.

  20. Exploring String Theory Backgrounds

    CERN Document Server

    Williams, B P

    2004-01-01

    This thesis examines phenomenological and theoretical questions by exploring string theoretic backgrounds. Part I focuses on cosmology. First we propose that the induced metric along a brane moving through a curved bulk may be interpreted as the cosmology of the brane universe, providing a resolution to the apparent cosmological singularity on the brane. We then look at various decay channels of the certain meta-stable de Sitter vacua and show that there exist NS5-brane meditated decays which are much faster than decays to decompactification. Part II discusses a new class of nongeometric vacua in string theory. These backgrounds may be described locally as T2 fibrations. By enlarging the monodromy group of the fiber to include perturbative stringy duality symmetries we are able to explicitly construct nongeometric backgrounds.

  1. Intermingling of chromosome territories in interphase suggests role in translocations and transcription-dependent associations.

    Directory of Open Access Journals (Sweden)

    Miguel R Branco

    2006-05-01

    Full Text Available After mitosis, mammalian chromosomes partially decondense to occupy distinct territories in the cell nucleus. Current models propose that territories are separated by an interchromatin domain, rich in soluble nuclear machinery, where only rare interchromosomal interactions can occur via extended chromatin loops. In contrast, recent evidence for chromatin mobility and high frequency of chromosome translocations are consistent with significant levels of chromosome intermingling, with important consequences for genome function and stability. Here we use a novel high-resolution in situ hybridization procedure that preserves chromatin nanostructure to show that chromosome territories intermingle significantly in the nucleus of human cells. The degree of intermingling between specific chromosome pairs in human lymphocytes correlates with the frequency of chromosome translocations in the same cell type, implying that double-strand breaks formed within areas of intermingling are more likely to participate in interchromosomal rearrangements. The presence of transcription factories in regions of intermingling and the effect of transcription impairment on the interactions between chromosomes shows that transcription-dependent interchromosomal associations shape chromosome organization in mammalian cells. These findings suggest that local chromatin conformation and gene transcription influence the extent with which chromosomes interact and affect their overall properties, with direct consequences for cell-type specific genome stability.

  2. Identification of chromosomal translocation hotspots via scan statistics

    Science.gov (United States)

    Silva, Israel T.; Rosales, Rafael A.; Holanda, Adriano J.; Nussenzweig, Michel C.; Jankovic, Mila

    2014-01-01

    Motivation: The detection of genomic regions unusually rich in a given pattern is an important undertaking in the analysis of next-generation sequencing data. Recent studies of chromosomal translocations in activated B lymphocytes have identified regions that are frequently translocated to c-myc oncogene. A quantitative method for the identification of translocation hotspots was crucial to this study. Here we improve this analysis by using a simple probabilistic model and the framework provided by scan statistics to define the number and location of translocation breakpoint hotspots. A key feature of our method is that it provides a global chromosome-wide nominal control level to clustering, as opposed to previous methods based on local criteria. While being motivated by a specific application, the detection of unusual clusters is a widespread problem in bioinformatics. We expect our method to be useful in the analysis of data from other experimental approaches such as of ChIP-seq and 4C-seq. Results: The analysis of translocations from B lymphocytes with the method described here reveals the presence of longer hotspots when compared with those defined previously. Further, we show that the hotspot size changes substantially in the absence of DNA repair protein 53BP1. When 53BP1 deficiency is combined with overexpression of activation-induced cytidine deaminase, the hotspot length increases even further. These changes are not detected by previous methods that use local significance criteria for clustering. Our method is also able to identify several exclusive translocation hotspots located in genes of known tumor supressors. Availability and implementation: The detection of translocation hotspots is done with hot_scan, a program implemented in R and Perl. Source code and documentation are freely available for download at https://github.com/itojal/hot_scan. Contact: isilva@rockefeller.edu Supplementary information: Supplementary data are available at Bioinformatics

  3. Backgrounded but not peripheral

    DEFF Research Database (Denmark)

    Hovmark, Henrik

    2013-01-01

    -cultural construction of identity, and, as a matter of fact, that their role might be quite important. I argue that the DDAs are backgrounded but not peripheral, i.e. marginal or insignificant. And I introduce the notion of “contextualization cue” in this argument (Levinson, 2003a, Gumperz, 1992)....

  4. China: Background Notes Series.

    Science.gov (United States)

    Reams, Joanne Reppert

    Concise background information on the People's Republic of China is provided. The publication begins with a profile of the country, outlining the people, geography, economy, and membership in international organizations. The bulk of the document then discusses in more detail China's people, geography, history, government, education, economy, and…

  5. Nondriven Polymer Translocation Through a Nanopore:Scaling for Translocation Time with Chain Length

    Institute of Scientific and Technical Information of China (English)

    LI Hui; ZHANG Jing; LIU Hong; SUN Chia-chung

    2011-01-01

    We investigated the dynamics of the passage for a polymer chain through a nanopore in the absence of any external driving force with Weeks-Chandler-Andersen potential in two-dimensional simulations,in particular,focused our attention on the scaling law of the mean translocation time.We found that the effect of hydrodynamic interactions is the major factor in determining the scaling exponents with increasing pore size.The scaling close to N1+2v was observed when the hydrodynamic interactions were screened in the cases of small pore sizes,while the scaling close to N3v was obtained when the hydrodynamic interactions were present in the cases of large pore sizes.

  6. Role of intestinal bacterial overgrowth and intestinal motility in bacterial translocation in experimental cirrhosis Papel del sobrecrecimiento bacteriano intestinal y de la motilidad intestinal en la traslocación bacteriana en un modelo experimental de cirrosis

    OpenAIRE

    Sánchez, E.; Casafont, F; Guerra, A; Benito, I.; Pons-Romero, F

    2005-01-01

    Background: intestinal bacterial overgrowth (IBO) is related to small bowel motility and has been involved in the pathogenesis of bacterial translocation (BT) in experimental models, and both overgrowing gut flora and translocating bacteria to mesenteric lymph nodes are common features in cirrhosis. Objectives: the aims of this study were to analyze cecal aerobic bacteria and intestinal transit in cirrhotic rats, and their relationship with BT, evaluating the role of intestinal bacterial over...

  7. Effects of rifaximin on bacterial translocation in thioacetamide-induced liver injury in rats.

    Science.gov (United States)

    Harputluoglu, Murat M M; Demirel, Ulvi; Gul, Mehmet; Temel, Ismail; Gursoy, Sule; Selcuk, Engin Burak; Aladag, Murat; Bilgic, Yilmaz; Gunduz, Ercan; Seckin, Yuksel

    2012-08-01

    Intestinal bacterial overgrowth (IBO) and increased mucosal permeability are suggested to increase bacterial translocation (BT) in liver injury. Rifaximin (RIF) is a minimally absorbed oral antimicrobial agent that restores gut microflora imbalance. The aim of the present study was to investigate the effects of RIF on BT frequency in thioacetamide (TAA)-induced liver injury. Group 1 was the control. In group 2 (TAA), rats received TAA daily for 3 days. In group 3 (TAA + RIF), RIF was commenced on the same day as the first dose of TAA. In group 4 (RIF), rats received only RIF. Ileal aspirate Escherichia coli counts were significantly lower in the TAA + RIF group than in TAA group. There was no difference in BT frequency between the TAA and TAA + RIF groups. Our results suggest that factors such as intestinal barrier dysfunction and impaired host immune shield, apart from IBO, play an important role in BT in this model.

  8. MYC translocation partner gene determines survival of patients with large B-cell lymphoma with MYC- or double-hit MYC/BCL2 translocations

    DEFF Research Database (Denmark)

    Pedersen, Mette Ø; Gang, Anne O; Poulsen, Tim S;

    2014-01-01

    In large B-cell lymphoma (LBCL) MYC- and MYC/BCL2 double-hit (DH) translocations have been associated with inferior survival. We hypothesised that the negative prognostic impact of MYC translocation was determined by an immunoglobulin MYC translocation partner gene (IG-MYC), as opposed to a non-i...

  9. Factors Affecting Polymer Translocation Through a Nanopore in a Membrane

    Institute of Scientific and Technical Information of China (English)

    Tao Chen; Teng Lu; Hao-jun Liang

    2008-01-01

    Monte Carlo simulations were used to study the translocation of a flexible polymer through a pore in a membrane, assuming an attractive interaction between the monomers and the membrane on the trans side of the membrane and no interaction on the cis side. For the case T<Tc (the temperature corresponding to the minimum in the translocation time τ), the value of τ decreases with increasing temperature, whereas for T>Tc, τ increases with increasing temperature. The translocation time depends on the absorbed energy uo in a nontrivial way. The value of τ increases initially upon increasing uo before it begins to decrease. The variation of the translocation time with respect to the solvent quality was also studied. It showed that there is a transition, as the solvent quality improves from "poor" to "good": when εAB<εc (the interaction energy corresponding to the minimum in τ), τ decreases with increasing the value of εAB; when εAB>εc, τ increases with increasing εAB. When the chain length was changed, it was found that when the absorbed energy uo was greater than uc, τ was proportional to N1.602; for uo<uc, τ∝N2.248. As the solvent quality improved from "poor" to "good," the translocation probability increased initially before becoming stable.

  10. Obstructed Bile Duct as a Trigger for Microbe's Translocation?

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    To assess the potential mechanisms of bacterial translocation in a murine model of obstructive jaundice. Methods: Adult rats were randomized to be operated on for ligation or sham-ligation of the common bile duct. Bacterial translocation to the mesenteric lymph nodes (MLNs), liver, spleen, portal blood and systemic circulation and bacterial population levels in the ceca were quantitated after 7 and 14 days. The terminal ilea were histologically examined by light and transmission electron microscopy. Results: Bacterial translocation to the MNLs was seen in both 7 (10/17) and 14 (11/18) day ligated animals, but not found in their corresponding controls (both 0/8). No significant difference in the cecal bacterial population levels was found between the ligated groups and their corresponding control groups, also between the two subgroups that were set up within each ligated group according to the presence or absence of bacteria in the MLNs. In the ligated rats, light microscopy demonstrated subepithelial edema in association with infiltration of flammatory cells and, transmission electron microscopy showed that the enterocytes were injured with abnormal microvilli, swollen mitochondria, unclear endoplasmic reticulum and cytoplasm with bubble degeneration. However, the ilea from the controls appeared normal. Conclusions: Obstructive jaundice promotes bacterial translocation in rats. The gut mucosal damage rather than the intestinal bacterial overgrowth may play a crucial role in bacterial translocation.

  11. Nonabsorbable Antibiotics Reduce Bacterial and Endotoxin Translocation in Hepatectomised Rats

    Directory of Open Access Journals (Sweden)

    S. K. Kakkos

    1997-01-01

    Full Text Available There is increasing evidence that septic complications, occurring after major hepatectomies, may be caused by gram negative bacteria, translocating from the gut. We investigated in rats, the effect of extended hepatectomy on the structure and morphology of the intestinal mucosa as well as on the translocation of intestinal bacteria and endotoxins. We also examined the effect of nonabsorbable antibiotics on reducing the intestinal flora and consequently the phenomenon of translocation by administering neomycin sulphate and cefazoline. Hepatectomy was found to increase translocation, while administration of nonabsorbable antibiotics decreased it significantly. In addition, hepatectomy increased the aerobic cecal bacterial population, which normalised in the group receiving antibiotics. Among the histological parameters evaluated, villus height demonstrated a significant reduction after hepatectomy, while the number of villi per cm and the number of mitoses per crypt, remained unchanged. Our results indicate that administration of nonabsorbable antibiotics presents a positive effect on bacterial and endotoxin translocation after extended hepatectomy, and this may be related to reduction of colonic bacterial load as an intraluminal effect of antibiotics.

  12. A somatic origin of homologous Robertsonian translocations and isochromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, W.P.; Bernasconi, F.; Schinzel, A.A. (Univ. of Zurich (Switzerland)); Basaran, S.; Yueksel-Apak, M. (Univ. of Istanbul (Turkey)); Neri, G. (Universita Cattolica, Rome (Italy)); Serville, F. (Hopital d' Enfants Pellegrin, Bordeaux (France)); Balicek, P.; Haluza, R. (Univ. Hospital of Hradeck Kralove, Hradec Kralove (Czech Republic)); Farah, L.M.S. (Escuola Paulista de Medicina, Sao Paulo (Brazil)) (and others)

    1994-02-01

    One t(14q 14q), three t(15q 15q), two t(21q21q), and two t(22q22q) nonmosaic, apparently balanced, de novo Robertsonian translocation cases were investigated with polymorphic markers to establish the origin of the translocated chromosomes. Four cases had results indicative of an isochromosome: one t(14q14q) case with mild mental retardation and maternal uniparental disomy (UPD) for chromosome 14, one t(15q15q) case with the Prader-Willi syndrome and UPD(15), a phenotypically normal carrier of t(22q22q) with maternal UPD(22), and a phenotypically normal t(21q21q) case of paternal UPD(21). All UPD cases showed complete homozygosity throughout the involved chromosome, which is supportive of a postmeiotic origin. In the remaining four cases, maternal and paternal inheritance of the involved chromosome was found, which unambiguously implies a somatic origin. One t(15q15q) female had a child with a ring chromosome 15, which was also of probable postmeiotic origin as recombination between grandparental haplotypes had occurred prior to ring formation. UPD might be expected to result from de novo Robertsonian translocations of meiotic origin; however, all de novo homologous translocation cases, so far reported, with UPD of chromosomes 14, 15, 21, or 22 have been isochromosomes. These data provide the first direct evidence that nonmosaic Robertsonian translocations, as well as isochromosomes, are commonly the result of a mitotic exchange. 75 refs., 1 fig., 4 tabs.

  13. Electrostatics of polymer translocation events in electrolyte solutions.

    Science.gov (United States)

    Buyukdagli, Sahin; Ala-Nissila, T

    2016-07-07

    We develop an analytical theory that accounts for the image and surface charge interactions between a charged dielectric membrane and a DNA molecule translocating through the membrane. Translocation events through neutral carbon-based membranes are driven by a competition between the repulsive DNA-image-charge interactions and the attractive coupling between the DNA segments on the trans and the cis sides of the membrane. The latter effect is induced by the reduction of the coupling by the dielectric membrane. In strong salt solutions where the repulsive image-charge effects dominate the attractive trans-cis coupling, the DNA molecule encounters a translocation barrier of ≈10 kBT. In dilute electrolytes, the trans-cis coupling takes over image-charge forces and the membrane becomes a metastable attraction point that can trap translocating polymers over long time intervals. This mechanism can be used in translocation experiments in order to control DNA motion by tuning the salt concentration of the solution.

  14. Meiotic behaviour of evolutionary sex-autosome translocations in Bovidae.

    Science.gov (United States)

    Vozdova, Miluse; Ruiz-Herrera, Aurora; Fernandez, Jonathan; Cernohorska, Halina; Frohlich, Jan; Sebestova, Hana; Kubickova, Svatava; Rubes, Jiri

    2016-09-01

    The recurrent occurrence of sex-autosome translocations during mammalian evolution suggests common mechanisms enabling a precise control of meiotic synapsis, recombination and inactivation of sex chromosomes. We used immunofluorescence and FISH to study the meiotic behaviour of sex chromosomes in six species of Bovidae with evolutionary sex-autosome translocations (Tragelaphus strepsiceros, Taurotragus oryx, Tragelaphus imberbis, Tragelaphus spekii, Gazella leptoceros and Nanger dama ruficollis). The autosomal regions of fused sex chromosomes showed normal synapsis with their homologous counterparts. Synapsis in the pseudoautosomal region (PAR) leads to the formation of characteristic bivalent (in T. imberbis and T. spekii with X;BTA13/Y;BTA13), trivalent (in T. strepsiceros and T. oryx with X/Y;BTA13 and G. leptoceros with X;BTA5/Y) and quadrivalent (in N. dama ruficollis with X;BTA5/Y;BTA16) structures at pachynema. However, when compared with other mammals, the number of pachynema lacking MLH1 foci in the PAR was relatively high, especially in T. imberbis and T. spekii, species with both sex chromosomes involved in sex autosome translocations. Meiotic transcriptional inactivation of the sex-autosome translocations assessed by γH2AX staining was restricted to their gonosomal regions. Despite intraspecies differences, the evolutionary fixation of sex-autosome translocations among bovids appears to involve general mechanisms ensuring sex chromosome pairing, synapsis, recombination and inactivation.

  15. The Cosmic Microwave Background

    Directory of Open Access Journals (Sweden)

    Jones Aled

    1998-01-01

    Full Text Available We present a brief review of current theory and observations of the cosmic microwave background (CMB. New predictions for cosmological defect theories and an overview of the inflationary theory are discussed. Recent results from various observations of the anisotropies of the microwave background are described and a summary of the proposed experiments is presented. A new analysis technique based on Bayesian statistics that can be used to reconstruct the underlying sky fluctuations is summarised. Current CMB data is used to set some preliminary constraints on the values of fundamental cosmological parameters $Omega$ and $H_circ$ using the maximum likelihood technique. In addition, secondary anisotropies due to the Sunyaev-Zel'dovich effect are described.

  16. The extragalactic IR background

    CERN Document Server

    De Zotti, G; Mazzei, P; Toffolatti, L; Danese, L; De Zotti, G; Franceschini, A; Mazzei, P; Toffolatti, L; Danese, L

    1994-01-01

    Current limits on the intensity of the extragalactic infrared background are consistent with the expected contribution from evolving galaxies. Depending on the behaviour of the star formation rate and of the initial mass function, we can expect that dust extinction during early evolutionary phases ranges from moderate to strong. An example of the latter case may be the ultraluminous galaxy IRAS F10214 + 4724. The remarkable lack of high redshift galaxies in faint optically selected samples may be indirect evidence that strong extinction is common during early phases. Testable implications of different scenarios are discussed; ISO can play a key role in this context. Estimates of possible contributions of galaxies to the background under different assumptions are presented. The COBE/FIRAS limits on deviations from a blackbody spectrum at sub-mm wavelengths already set important constraints on the evolution of the far-IR emission of galaxies and on the density of obscured (``Type 2'') AGNs. A major progress in ...

  17. Characterization of wheat - Psathyrostachys huashanica small segment translocation line with enhanced kernels per spike and stripe rust resistance.

    Science.gov (United States)

    Kang, Hou-Yang; Zhang, Zhi-Juan; Xu, Li-Li; Qi, Wei-Liang; Tang, Yao; Wang, Hao; Zhu, Wei; Li, Dai-Yan; Zeng, Jian; Wang, Yi; Fan, Xing; Sha, Li-Na; Zhang, Hai-Qin; Zhou, Yong-Hong

    2016-04-01

    Psathyrostachys huashanica Keng (2n = 2x = 14, NsNs), a distant wild relative of common wheat, possesses rich potentially valuable traits, such as disease resistance and more spikelets and kernels per spike, that could be useful for wheat genetic improvement. Development of wheat - P. huashanica translocation lines will facilitate its practical utilization in wheat breeding. In the present study, a wheat - P. huashanica small segmental translocation line, K-13-835-3, was isolated and characterized from the BC1F5 population of a cross between wheat - P. huashanica amphiploid PHW-SA and wheat cultivar CN16. Cytological studies showed that the mean chromosome configuration of K-13-835-3 at meiosis was 2n = 42 = 0.10 I + 19.43 II (ring) + 1.52 II (rod). GISH analyses indicated that chromosome composition of K-13-835-3 included 40 wheat chromosomes and a pair of wheat - P. huashanica translocation chromosomes. FISH results demonstrated that the small segment from an unidentified P. huashanica chromosome was translocated into wheat chromosome arm 5DS, proximal to the centromere region of 5DS. Compared with the cultivar wheat parent CN16, K-13-835-3 was highly resistant to stripe rust pathogens prevalent in China. Furthermore, spikelets and kernels per spike in K-13-835-3 were significantly higher than those of CN16 in two growing seasons. These results suggest that the desirable genes from P. huashanica were successfully transferred into CN16 background. This translocation line could be used as novel germplasm for high-yield and, eventually, resistant cultivar breeding.

  18. Multiscale modeling of biopolymer translocation through a nanopore

    CERN Document Server

    Fyta, M G; Kaxiras, E; Succi, S; Fyta, Maria; Melchionna, Simone; Kaxiras, Efthimios; Succi, Sauro

    2007-01-01

    We employ a multiscale approach to model the translocation of biopolymers through nanometer size pores. Our computational scheme combines microscopic Langevin molecular dynamics (MD) with a mesoscopic lattice Boltzmann (LB) method for the solvent dynamics, explicitly taking into account the interactions of the molecule with the surrounding fluid. Both dynamical and statistical aspects of the translocation process were investigated, by simulating polymers of various initial configurations and lengths. For a representative molecule size, we explore the effects of important parameters that enter in the simulation, paying particular attention to the strength of the molecule-solvent coupling and of the external electric field which drives the translocation process. Finally, we explore the connection between the generic polymers modeled in the simulation and DNA, for which interesting recent experimental results are available.

  19. Prenatal diagnosis of an autosomal translocation with regular trisomy 21.

    Science.gov (United States)

    Tunca, Yusuf; Deveci, M Salih; Koc, Altug; Kaya, Halide; Alanbay, Ibrahim; Coksuer, Hakan; Dede, Murat

    2013-06-01

    The coincidence of trisomy 21 and a structural rearrangement is very rare, and even it has not been reported as a prenatal diagnosis yet. In this article, we present an autosomal translocation carrier fetus with trisomy 21: 47,XX,+21, t(3;8)(p21;q24). Although the coincidence of reciprocal translocation and trisomy may be seen in reciprocal translocation carrier families, de novo cases are extremely rare. The presented case is diagnosed by amniocentesis, which was performed because of abnormal fetal ultrasonographic findings and increased trisomy 21 risk at maternal serum screening test. The postmortem pathologic examination of the fetus revealed that the findings of hypertelorism and right lung with two lobes are interesting novel findings of our cases associated with the breakpoints 3p21 and 8q24.

  20. Enhancing nuclear translocation: perspectives in inhaled corticosteroid therapy.

    Science.gov (United States)

    Hakim, Amir; Usmani, Omar S

    2015-01-01

    Corticosteroids are widely used in the treatment of asthma and chronic obstructive pulmonary disease (COPD). In contrast to their use in mild-to-moderate asthma, they are less efficacious in improving lung function and controlling the underlying inflammation in COPD. In most clinical trials, corticosteroids have shown little benefit in COPD, but have shown a greater clinical effect in combination with long-acting bronchodilators. Impaired corticosteroid activation of the glucocorticoid receptor (GR) has been reported in corticosteroid-insensitive individuals. Reversal of corticosteroid-insensitivity by enhancing GR nuclear translocation is a potential therapeutic target. Preclinical studies suggest members of the nuclear receptor superfamily may facilitate glucocorticoid receptor nuclear translocation. Unravelling the mechanisms that govern GR nuclear translocation may identify novel therapeutic targets for reversing corticosteroid-insensitivity.

  1. High-speed detection of DNA translocation in nanopipettes.

    Science.gov (United States)

    Fraccari, Raquel L; Ciccarella, Pietro; Bahrami, Azadeh; Carminati, Marco; Ferrari, Giorgio; Albrecht, Tim

    2016-04-14

    We present a high-speed electrical detection scheme based on a custom-designed CMOS amplifier which allows the analysis of DNA translocation in glass nanopipettes on a microsecond timescale. Translocation of different DNA lengths in KCl electrolyte provides a scaling factor of the DNA translocation time equal to p = 1.22, which is different from values observed previously with nanopipettes in LiCl electrolyte or with nanopores. Based on a theoretical model involving electrophoresis, hydrodynamics and surface friction, we show that the experimentally observed range of p-values may be the result of, or at least be affected by DNA adsorption and friction between the DNA and the substrate surface.

  2. Mechanism for translocation of fluoroquinolones across lipid membranes

    DEFF Research Database (Denmark)

    Cramariuc, O.; Rog, T.; Javanainen, M.

    2012-01-01

    Classical atom-scale molecular dynamics simulations, constrained free energy calculations, and quantum mechanical (QM) calculations are employed to study the diffusive translocation of ciprofloxacin (CPFX) across lipid membranes. CPFX is considered here as a representative of the fluoroquinolone...... antibiotics class. Neutral and zwitterionic CPFX coexist at physiological pH, with the latter being predominant. Simulations reveal that only the neutral form permeates the bilayer, and it does so through a novel mechanism that involves dissolution of concerted stacks of zwitterionic ciprofloxacins....... Subsequent QM analysis of the observed molecular stacking shows the important role of partial charge neutralization in the stacks, highlighting how the zwitterionic form of the drug is neutralized for translocation. The findings propose a translocation mechanism in which zwitterionic CPFX molecules approach...

  3. Multiple aspects of ATP-dependent nucleosome translocation by RSC and Mi-2 are directed by the underlying DNA sequence.

    Directory of Open Access Journals (Sweden)

    Joke J F A van Vugt

    Full Text Available BACKGROUND: Chromosome structure, DNA metabolic processes and cell type identity can all be affected by changing the positions of nucleosomes along chromosomal DNA, a reaction that is catalysed by SNF2-type ATP-driven chromatin remodelers. Recently it was suggested that in vivo, more than 50% of the nucleosome positions can be predicted simply by DNA sequence, especially within promoter regions. This seemingly contrasts with remodeler induced nucleosome mobility. The ability of remodeling enzymes to mobilise nucleosomes over short DNA distances is well documented. However, the nucleosome translocation processivity along DNA remains elusive. Furthermore, it is unknown what determines the initial direction of movement and how new nucleosome positions are adopted. METHODOLOGY/PRINCIPAL FINDINGS: We have used AFM imaging and high resolution PAGE of mononucleosomes on 600 and 2500 bp DNA molecules to analyze ATP-dependent nucleosome repositioning by native and recombinant SNF2-type enzymes. We report that the underlying DNA sequence can control the initial direction of translocation, translocation distance, as well as the new positions adopted by nucleosomes upon enzymatic mobilization. Within a strong nucleosomal positioning sequence both recombinant Drosophila Mi-2 (CHD-type and native RSC from yeast (SWI/SNF-type repositioned the nucleosome at 10 bp intervals, which are intrinsic to the positioning sequence. Furthermore, RSC-catalyzed nucleosome translocation was noticeably more efficient when beyond the influence of this sequence. Interestingly, under limiting ATP conditions RSC preferred to position the nucleosome with 20 bp intervals within the positioning sequence, suggesting that native RSC preferentially translocates nucleosomes with 15 to 25 bp DNA steps. CONCLUSIONS/SIGNIFICANCE: Nucleosome repositioning thus appears to be influenced by both remodeler intrinsic and DNA sequence specific properties that interplay to define ATPase

  4. Scintigraphic visualization of bacterial translocation in experimental strangulated intestinal obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Galeev, Yu.M.; Popov, M.V.; Salato, O.V. [Siberian Branch of Russian Academy of Medical Science, Research Centre of Reparative and Restorative Surgery, East Siberian Research Centre, 100 Yubileyniy, P.O. Box 23, Irkutsk (Russian Federation); Lishmanov, Yu.B. [Siberian Branch of Russian Academy of Medical Science, Research and Development Institute of Cardiology, Tomsk Research Centre, Tomsk (Russian Federation); Grigorev, E.G.; Aparcin, K.A. [Siberian Branch of Russian Academy of Medical Science, Research Centre of Reparative and Restorative Surgery, East Siberian Research Centre, 100 Yubileyniy, P.O. Box 23, Irkutsk (Russian Federation); Irkutsk State Medical University, Department of Hospital Surgery, Irkutsk (Russian Federation)

    2009-11-15

    The purpose of this study was to obtain scintigraphic images depicting translocation of {sup 99m}Tc-labelled Escherichia coli bacteria through the intestinal barrier and to quantify this process using methods of nuclear medicine. Thirty male Wistar rats (including 20 rats with modelled strangulated intestinal obstruction and 10 healthy rats) were used for bacterial scintigraphy. {sup 99m}Tc-labelled E. coli bacteria ({sup 99m}Ts-E. coli) with an activity of 7.4-11.1 MBq were administered into a section of the small intestine. Scintigraphic visualization of bacterial translocation into organs and tissues of laboratory animals was recorded in dynamic (240 min) and static (15 min) modes. The number of labelled bacteria, which migrated through the intestinal barrier, was quantified by calculating the translocation index (TI). Control indicated no translocation of {sup 99m}Ts-E. coli administered into the intestine through the parietes of the small intestine's distal part in healthy animals. Animals with strangulated obstruction demonstrated different migration strength and routes of labelled bacteria from strangulated and superior to strangulation sections of the small intestine. {sup 99m}Ts-E. coli migrated from the strangulated loop into the peritoneal cavity later causing systemic bacteraemia through peritoneal resorption. The section of the small intestine, which was superior to the strangulation, demonstrated migration of labelled bacteria first into the portal and then into the systemic circulation. The strangulated section of the small intestine was the main source of bacteria dissemination since the number of labelled bacteria, which migrated from this section significantly, exceeded that of the area superior to the strangulation section of the small intestine (p = 0.0003). Bacterial scintigraphy demonstrated the possibility of visualizing migration routes of labelled bacteria and quantifying their translocation through the intestinal barrier. This

  5. Spontaneous modification of the oxoglutarate translocator in vivo.

    Science.gov (United States)

    Duyckaerts, C; Sluse-Goffart, C M; Sluse, F E; Gosselin-Rey, C; Liébecq, C

    1984-07-16

    In studying the oxoglutarate translocator of rat-heart mitochondria over many years, we have observed an unexpected decrease in its efficiency. It has been divided by 2.48 +/- 0.07, (S.E.M.) for the exchange of external oxoglutarate for internal malate at 2 degrees C when the internal-malate concentration is 4 mM and is accompanied by an increase in its concentration (multiplied by 1.61 +/- 0.02, S.E.M.). The affinity of the external sites of the translocator for the external oxoglutarate is unchanged as well as the binding and kinetic cooperativities of the external oxoglutarate. This shows that the external side of the translocator has not been modified and suggests that its central part has not been modified either. The apparent Michaelis constant of the internal malate is increased (multiplied by 1.74 +/- 0.23, S.E.M.) suggesting that the translocator has been modified on its matricial side. Some control experiments show that a change in the diet of the rats, despite its effect on the fatty-acid content of the mitoplasts, is probably not responsible for the observed modification. As it is nevertheless very likely that changes of the oxoglutarate translocator have occurred in vivo, it is proposed that the observed modification has a genetic origin. The existence of two antagonist changes which are not directly related suggests that one of them is a response of the organism against the other; thus the oxoglutarate translocator may play a regulatory rôle in certain physiological conditions.

  6. Exercise-induced translocation of protein kinase C and production of diacylglycerol and phosphatidic acid in rat skeletal muscle in vivo. Relationship to changes in glucose transport.

    Science.gov (United States)

    Cleland, P J; Appleby, G J; Rattigan, S; Clark, M G

    1989-10-25

    Contraction-induced translocation of protein kinase C (Richter E.A., Cleland, P.J.F., Rattigan, S., and Clark, M.G. (1987) FEBS Lett. 217, 232-236) implies a role for this enzyme in muscle contraction or the associated metabolic adjustments. In the present study, this role is further examined particularly in relation to changes in glucose transport. Electrical stimulation of the sciatic nerve of the anesthetized rat in vivo led to a time-dependent translocation of protein kinase C and a 2-fold increase in the concentrations of both diacylglycerol and phosphatidic acid. Maximum values for the latter were reached at 2 min and preceded the maximum translocation of protein kinase C (10 min). Stimulation of muscles in vitro increased the rate of glucose transport, but this required 20 min to reach maximum. There was no reversal of translocation or decrease in the concentrations of diacylglycerol and phosphatidic acid even after 30 min of rest following a 5-min period of stimulation in vivo. Translocation was not influenced by variations in applied load at maximal fiber recruitment but was dependent on the frequency of nontetanic stimuli, reaching a maximum at 4 Hz. The relationship between protein kinase C and glucose transport was also explored by varying the number of tetanic stimuli. Whereas only one train of stimuli (200 ms, 100 Hz) was required for maximal effects on protein kinase C, diacylglycerol, and phosphatidic acid, more than 35 trains of stimuli were required to activate glucose transport. It is concluded that the production of diacylglycerol and the translocation of protein kinase C may be causally related. However, if the translocated protein kinase C is involved in the activation of glucose transport during muscle contractions, an accumulated exposure to Ca2+, resulting from multiple contractions, would appear to be necessary.

  7. Hard Sphere Diffusion Behaviour of Polymer Translocating through Interacting Pores

    Institute of Scientific and Technical Information of China (English)

    SUN Li-Zhen; LUO Meng-Bo

    2008-01-01

    The translocation of polymer chain through a small pore from a high concentration side (cis side) to a low concentration side (trans side) is simulated by using Monte Carlo technique. The effect of the polymer-pore interaction on the translocation is studied. We find a special interaction at which the decay of the number of polymer chain, N, at the cis side obeys Fick's law, i.e. N decreases exponentially with time. The behaviour is analogous to the diffusion of hard sphere.

  8. Enhanced stimulation of chromosomal translocations and sister chromatid exchanges by either HO-induced double-strand breaks or ionizing radiation in Saccharomyces cerevisiae yku70 mutants

    Energy Technology Data Exchange (ETDEWEB)

    Fasullo, Michael [Ordway Research Institute, 150 New Scotland Avenue, Albany, NY 12209 (United States)]. E-mail: mfasullo@ordwayresearch.org; St Amour, Courtney [Ordway Research Institute, 150 New Scotland Avenue, Albany, NY 12209 (United States); Zeng Li [Ordway Research Institute, 150 New Scotland Avenue, Albany, NY 12209 (United States)

    2005-10-15

    DNA double-strand break (DSB) repair occurs by homologous recombination (HR) or non-homologous endjoining (NHEJ). In Saccharomyces cerevisiae, expression of both MAT a and MAT{alpha} inhibits NHEJ and facilitates DSB-initiated HR. We previously observed that DSB-initiated recombination between two his3 fragments, his3-{delta}5' and his3-{delta}3'::HOcs is enhanced in haploids and diploids expressing both MAT a and MAT{alpha} genes, regardless of the position or orientation of the his3 fragments. Herein, we measured frequencies of DNA damage-associated translocations and sister chromatid exchanges (SCEs) in yku70 haploid mutants, defective in NHEJ. Translocation and SCE frequencies were measured in strains containing the same his3 fragments after DSBs were made directly at trp1::his3-{delta}3'::HOcs. Wild type and yku70 cells were also exposed to ionizing radiation and radiomimetic agents methyl methanesulfonate (MMS), phleomycin, and 4-nitroquinolone-1-oxide (4-NQO). Frequencies of X-ray-associated and DSB-initiated translocations were five-fold higher in yku70 mutants compared to wild type; however, frequencies of phleomycin-associated translocations were lower in the yku70 haploid mutant. Frequencies of DSB-initiated SCEs were 1.8-fold higher in the yku70 mutant, compared to wild type. Thus, DSB-initiated HR between repeated sequences on non-homologous chromosomes and sister chromatids occurs at higher frequencies in yku70 haploid mutants; however, higher frequencies of DNA damage-associated HR in yku70 mutants depend on the DNA damaging agent.

  9. Electro-acupuncture for STAT3 expression and nuclear translocation in hippocampal tissues of rats following cerebral ischemia/reperfusion

    Institute of Scientific and Technical Information of China (English)

    Lihong Kong; Xiaoling Zeng; Guojie Sun; Shenghong Liu

    2006-01-01

    BACKGROUND: It has been found in recent years that STATS widely distributes in nervous system, including hippocampal CA1-3 region, dentate gyrus and cerebral neocortex, etc. Ischemic brain injury can cause the release of some cytokines and growth factors, while electro-acupuncture may have multi-level, multi-channel and multi-target protective and interventional effects on ischemic brain injury.OBJ ECTIVE: To observe the effects of electro-acupuncture on STAT3 expression and nuclear translocation in hippocampal CA1 region of rat models of brain ischemia/reperfusion.DESIGN: Randomized and controlled observation.SETTING: Staff Room of Acupuncture and Moxibustion, Department of Acupuncture and Bone Injury,Hubei College of Traditional Chinese Medicine; Tongji Medical College, Huazhong University of Science and Technology.MATERTALS: Seventy-two healthy SD rats, of clean degree and either gender, weighing (200±20) g, were provided by the Experimental Animal Center of Hubei College of Traditional Chinese Medicine. STAT3monoclonal antibody was purchased from Santa Cruz Company, USA, and G-6805 electro-acupuncture instrument was purchased from Shanghai Medical Electronic Instruments Factory.METHODS: This experiment was carried out in the comprehensive laboratory of Department of Acupuncture and Bone Injury, Hubei College of Traditional Chinese Medicine between September 2005 and February 2006.Seventy-two rats were randomly divided into 4 groups: ① control group(n =6): Untouched. ② Sham-operation group (n =18): Artery was isolated, but without inserting thread bolt.③ Model group (n =24): Rat models of local brain ischemia/reperfusion were established with modified suture occlusion. ④Electro-acupuncture group (n =24): Dazhui and bilateral Neiguan points were selected for electro-acupuncture treatment. No. 28acupuncture needle of 3.33 cm was used in the treatment A G-6085 electro-acupuncture instrument with continuous wave, frequency of 120 times/min, intensity of 1 m

  10. Family Background and Entrepreneurship

    DEFF Research Database (Denmark)

    Lindquist, Matthew J.; Sol, Joeri; Van Praag, Mirjam

    Vast amounts of money are currently being spent on policies aimed at promoting entrepreneurship. The success of such policies, however, rests in part on the assumption that individuals are not ‘born entrepreneurs’. In this paper, we assess the importance of family background and neighborhood...... treatment within families by gender and birth order does little to further increase our estimates of the importance of family-wide factors. We then go on to show that neighborhood effects, sibling peer effects, and parental income and education explain very little of these correlations. Parental...

  11. Ultraviolet Background Radiation (Preprint)

    Science.gov (United States)

    1991-03-01

    importance is that the sky may be truly outstandingly black in the far ultraviolet, offering a "dark site " that is unprecedented in astronomy...Estimated spectral energy distribution of the night-sky background near the zenith at an excellent ground-based site on a moonless night and in a...1977. Ap. J. Suppl. 33:451 31. Henry, R. C. 1981. Ap. J. Lett. 244: L69 32. Henry, R. C. 1981. 16th Rencontre de Moriond, ed. J. Tran Thanh Van, p

  12. Malaysia; Background Paper

    OpenAIRE

    International Monetary Fund

    1996-01-01

    This Background Paper on Malaysia examines developments and trends in the labor market since the mid-1980s. The paper describes the changes in the employment structure and the labor force. It reviews wages and productivity trends and their effects on unit labor cost. The paper highlights that Malaysia’s rapid growth, sustained since 1987, has had a major impact on the labor market. The paper outlines the major policy measures to address the labor constraints. It also analyzes Malaysia’s r...

  13. Comprehensive postmortem analyses of intestinal microbiota changes and bacterial translocation in human flora associated mice.

    Directory of Open Access Journals (Sweden)

    Markus M Heimesaat

    Full Text Available BACKGROUND: Postmortem microbiological examinations are performed in forensic and medical pathology for defining uncertain causes of deaths and for screening of deceased tissue donors. Interpretation of bacteriological data, however, is hampered by false-positive results due to agonal spread of microorganisms, postmortem bacterial translocation, and environmental contamination. METHODOLOGY/PRINCIPAL FINDINGS: We performed a kinetic survey of naturally occurring postmortem gut flora changes in the small and large intestines of conventional and gnotobiotic mice associated with a human microbiota (hfa applying cultural and molecular methods. Sacrificed mice were kept under ambient conditions for up to 72 hours postmortem. Intestinal microbiota changes were most pronounced in the ileal lumen where enterobacteria and enterococci increased by 3-5 orders of magnitude in conventional and hfa mice. Interestingly, comparable intestinal overgrowth was shown in acute and chronic intestinal inflammation in mice and men. In hfa mice, ileal overgrowth with enterococci and enterobacteria started 3 and 24 hours postmortem, respectively. Strikingly, intestinal bacteria translocated to extra-intestinal compartments such as mesenteric lymphnodes, spleen, liver, kidney, and cardiac blood as early as 5 min after death. Furthermore, intestinal tissue destruction was characterized by increased numbers of apoptotic cells and neutrophils within 3 hours postmortem, whereas counts of proliferative cells as well as T- and B-lymphocytes and regulatory T-cells decreased between 3 and 12 hours postmortem. CONCLUSIONS/SIGNIFICANCE: We conclude that kinetics of ileal overgrowth with enterobacteria and enterococci in hfa mice can be used as an indicator for compromized intestinal functionality and for more precisely defining the time point of death under defined ambient conditions. The rapid translocation of intestinal bacteria starting within a few minutes after death will help

  14. Serological markers for inflammatory bowel disease in AIDS patients with evidence of microbial translocation.

    Directory of Open Access Journals (Sweden)

    Anupa Kamat

    Full Text Available BACKGROUND: Breakdown of the gut mucosal barrier during chronic HIV infection allows translocation of bacterial products such as lipopolysaccharides (LPS from the gut into the circulation. Microbial translocation also occurs in inflammatory bowel disease (IBD. IBD serological markers are useful in the diagnosis of IBD and to differentiate between Crohn's disease (CD and ulcerative colitis (UC. Here, we evaluate detection of IBD serological markers in HIV-infected patients with advanced disease and their relationship to HIV disease markers. METHODS: IBD serological markers (ASCA, pANCA, anti-OmpC, and anti-CBir1 were measured by ELISA in plasma from AIDS patients (n = 26 with low CD4 counts (<300 cells/µl and high plasma LPS levels, and results correlated with clinical data. For meta-analysis, relevant data were abstracted from 20 articles. RESULTS: IBD serological markers were detected in approximately 65% of AIDS patients with evidence of microbial translocation. An antibody pattern consistent with IBD was detected in 46%; of these, 75% had a CD-like pattern. Meta-analysis of data from 20 published studies on IBD serological markers in CD, UC, and non-IBD control subjects indicated that IBD serological markers are detected more frequently in AIDS patients than in non-IBD disease controls and healthy controls, but less frequently than in CD patients. There was no association between IBD serological markers and HIV disease markers (plasma viral load and CD4 counts in the study cohort. CONCLUSIONS: IBD serological markers may provide a non-invasive approach to monitor HIV-related inflammatory gut disease. Further studies to investigate their clinical significance in HIV-infected individuals are warranted.

  15. The SWI/SNF protein ATRX co-regulates pseudoautosomal genes that have translocated to autosomes in the mouse genome

    Directory of Open Access Journals (Sweden)

    Fernandes Andrew D

    2008-10-01

    Full Text Available Abstract Background Pseudoautosomal regions (PAR1 and PAR2 in eutherians retain homologous regions between the X and Y chromosomes that play a critical role in the obligatory X-Y crossover during male meiosis. Genes that reside in the PAR1 are exceptional in that they are rich in repetitive sequences and undergo a very high rate of recombination. Remarkably, murine PAR1 homologs have translocated to various autosomes, reflecting the complex recombination history during the evolution of the mammalian X chromosome. Results We now report that the SNF2-type chromatin remodeling protein ATRX controls the expression of eutherian ancestral PAR1 genes that have translocated to autosomes in the mouse. In addition, we have identified two potentially novel mouse PAR1 orthologs. Conclusion We propose that the ancestral PAR1 genes share a common epigenetic environment that allows ATRX to control their expression.

  16. Induction of small-segment-translocation between wheat and rye chromosomes

    Institute of Scientific and Technical Information of China (English)

    任正隆; 张怀琼

    1997-01-01

    A new approach to produce wheat-rye translocation, based on the genetic instability caused by monosomic addition of rye chromosome in wheat, is described. 1 283 plants from the selfed progenies of monosomic addition lines with single chromosome of inbred rye line R12 and complete chromosome complement of wheat cultivar Mianyang 11 were cytologically analyzed on a plant-by-plant basis by the improved C-banding technique. 63 of the plants, with 2n = 42, were found containing wheat-rye translocation or substitution, with a frequency of 4. 91% . Compared with the wheat parent, other 32 plants with 2n = 42 exhibited obvious phenotypic variation, but their com-ponent of rye chromosome could not be detected using the C-banding technique. In situ hybridization with a biotin-la-beled DNA probe was used to detect rye chromatin and to determine the insertion sites of rye segments in the wheat chromosomes. In 20 out of the 32 variant wheat plants, small segments of rye chromosomes were found being inserted into dif

  17. Ultraviolet Background Radiation

    Science.gov (United States)

    Henry, R. C.; Murthy, J.

    1993-12-01

    The UVX experiment was carried on the Space Shuttle Columbia between 1986 January 12 and 19 (STS-61C). Several ultraviolet spectrometers were used to obtain measurements of the diffuse ultraviolet background at 8 locations in the sky. We have reanalysed the UVX measurements of the surface brightness of the diffuse ultraviolet background above b = 40 using the dust-scattering model of Onaka & Kodaira (1991), which explicitly takes into account the variation of the source function with galactic longitude. The range of allowed values of interstellar grain albedoJa, and scattering asymmetry parameter g, is considerably expanded over those of a previous analysis. The new chi square probability contours come close to, but do not include, the values of a and g found for the interstellar grains by Witt et al. (1992) using the Ultraviolet Imaging Telescope (UIT) on the Astro mission. If we hypothesize in additon to the dust-scattered light an extragalactic component, of 300 1 100 photons cm-2 s-1 sr-1 A-1, attenuated by a cosecant b law, the new reduction of the UVX data gives complete consistency with the Witt et al. determination of the optical parameters of the grains in the ultraviolet. This work was supported by United States Air Force Contract F19628-93-K-0004, and by National Aeronautics and Space Administration grant NASA NAG5-619. We are grateful for the encouragement of Dr. Stephan Price, and we thank Dr. L. Danly for information. Onaka, T., & Kodaira, K. 1991, ApJ, 379, 532 Witt, A. N., Petersohn, J. K., Bohlin, R. C., O'Connell, R. W., Roberts, M. S., Smith, A. M., & Stecher, T. P. 1992, ApJ, 395, L5

  18. Unassisted translocation of large polypeptide domains across phospholipid bilayers.

    Science.gov (United States)

    Brambillasca, Silvia; Yabal, Monica; Makarow, Marja; Borgese, Nica

    2006-12-01

    Although transmembrane proteins generally require membrane-embedded machinery for integration, a few can insert spontaneously into liposomes. Previously, we established that the tail-anchored (TA) protein cytochrome b(5) (b5) can posttranslationally translocate 28 residues downstream to its transmembrane domain (TMD) across protein-free bilayers (Brambillasca, S., M. Yabal, P. Soffientini, S. Stefanovic, M. Makarow, R.S. Hegde, and N. Borgese. 2005. EMBO J. 24:2533-2542). In the present study, we investigated the limits of this unassisted translocation and report that surprisingly long (85 residues) domains of different sequence and charge placed downstream of b5's TMD can posttranslationally translocate into mammalian microsomes and liposomes at nanomolar nucleotide concentrations. Furthermore, integration of these constructs occurred in vivo in translocon-defective yeast strains. Unassisted translocation was not unique to b5 but was also observed for another TA protein (protein tyrosine phosphatase 1B) whose TMD, like the one of b5, is only moderately hydrophobic. In contrast, more hydrophobic TMDs, like synaptobrevin's, were incapable of supporting unassisted integration, possibly because of their tendency to aggregate in aqueous solution. Our data resolve long-standing discrepancies on TA protein insertion and are relevant to membrane evolution, biogenesis, and physiology.

  19. Concentration Polarization in Translocation of DNA through Nanopores and Nanochannels

    NARCIS (Netherlands)

    Das, Siddhartha; Dubsky, Pavel; Berg, van den Albert; Eijkel, J.C.T.

    2012-01-01

    In this Letter we provide a theory to show that high-field electrokinetic translocation of DNA through nanopores or nanochannels causes large transient variations of the ionic concentrations in front and at the back of the DNA due to concentration polarization (CP). The CP causes strong local conduc

  20. Three cases of mosaicism for balanced reciprocal translocations

    NARCIS (Netherlands)

    Leegte, B; Sikkema-Raddatz, B; Hordijk, R; Bouman, K; van Essen, T; Castedo, S; de Jong, B

    1998-01-01

    Mosaicism for a balanced reciprocal translocation (BRTM) is rare. As far as we know only 26 cases of BRTM, demonstrated in lymphocyte cultures, have been described, five of which had an abnormal phenotype. Prenatally three confirmed cases with a normal phenotypic outcome have been described. Here we

  1. Bioenergetic aspects of the translocation of macromolecules across bacterial membranes

    NARCIS (Netherlands)

    Palmen, Ronald; Driessen, Arnold J.M.; Hellingwerf, K

    1994-01-01

    Bacteria are extremely versatile in the sense that they have gained the ability to transport all three major classes of biopolymers through their cell envelope: proteins, nucleic acids, and polysaccharides. These macromolecules are translocated across membranes in a large number of cellular processe

  2. Driven translocation of a polymer: Fluctuations at work

    NARCIS (Netherlands)

    Dubbeldam, J.L.A.; Rostiashvii, V.G.; Milchev, A.; Vilgis, T.A.

    2013-01-01

    The impact of thermal fluctuations on the translocation dynamics of a polymer chain driven through a narrow pore has been investigated theoretically and by means of extensive molecular dynamics (MD) simulation. The theoretical consideration is based on the so-called velocity Langevin (V-Langevin) eq

  3. SecA supports a constant rate of preprotein translocation

    NARCIS (Netherlands)

    Tomkiewicz, D; Nouwen, N; van Leeuwen, R; Tans, S; Driessen, AJM

    2006-01-01

    In Escherichia coli, secretory proteins (preproteins) are translocated across the cytoplasmic membrane by the Sec system composed of a protein-conducting channel, SecYEG, and an ATP-dependent motor protein, SecA. After binding of the preprotein to SecYEG-bound SecA, cycles of ATP binding and hydroly

  4. Translocation of Polymer Chains Through a Channel with Complex Geometries

    Institute of Scientific and Technical Information of China (English)

    Zhi-yong Yang; Lin-xi Zhang; Jun Cheng

    2008-01-01

    The elastic behavior of a single chain transporting through complex channel which can be seen as the combination of three different channels (left channel, middle channel, and right channel, respectively) is investigated using the new pruned-enriched Rosenbluth method with importance sampling. The elastic force during the translocation process is calculated. At the entrance into the middle channel, there is the first plateau in the curve of the elastic force f (f0) versus x, here x represents the position of the first monomer along the x-axis direction. When the first monomer moves to a certain position, a second plateau is observed with the elastic force f<0, which represents spontaneous translocation. The free energy difference between the subchain in the right channel and the subchain in the left channel may drive the trauslocation. The influence of chain length and width of the left and right channels on the translocation process are also investigated. From the simulation results, more detailed explanations for the reason why the component translocation time is not the same for different channels can be presented.

  5. Ionizing Radiation Induces HMGB1 Cytoplasmic Translocation and Extracellular Release

    Institute of Scientific and Technical Information of China (English)

    Lili Wang; Li He; Guoqiang Bao; Xin He; Saijun Fan; Haichao Wang

    2016-01-01

    Objective A nucleosomal protein,HMGBI,can be secreted by activated immune cells or passively released by dying cells,thereby amplifying rigorous inflammatory responses.In this study we aimed to test the possibility that radiation similarly induces cytoplasmic HMGB1 translocation and release.Methods Human skin fibroblast (GM0639) and bronchial epithelial (16HBE) cells and rats were exposed to X-ray radiation,and HMGB1 translocation and release were then assessed by immunocytochemistry and immunoassay,respectively.Results At a wide dose range(4.0-12.0 Gy),X-ray radiation induced a dramatic cytoplasmic HMGB1 translocation,and triggered a time-and dose-dependent HMGB1 release both in vitro and in vivo.The radiation-mediated HMGB1 release was also associated with noticeable chromosomal DNA damage and loss of cell viability.Conclusions Radiation induces HMGB1 cytoplasmic translocation and extracellular release through active secretion and passive leakage processes.

  6. Genetic counseling in carriers of reciprocal translocations involving two autosomes

    Directory of Open Access Journals (Sweden)

    Bahareh Pourjafari

    2012-01-01

    Couples in which one partner is the carrier of such balanced translocation have increased risks of infertility, recurrent abortion, and delivery of chromosomally abnormal offspring. Genetic counseling of such couples, therefore, presents a unique challenge and should be considered in dealing with such families.

  7. Markers of immunity and bacterial translocation in cirrhosis

    DEFF Research Database (Denmark)

    Mortensen, Christian

    2015-01-01

    , in 38 patients with ascites, we found no association between bDNA and immunity, in contrast to some previous findings. In the final paper, exploring one possible translocation route, we hypothesized a difference in bDNA levels between the blood from the veins draining the gut on one hand and the liver...

  8. Centrifugally driven microfluidic disc for detection of chromosomal translocations

    DEFF Research Database (Denmark)

    Brøgger, Anna Line; Kwasny, Dorota; Bosco, Filippo G.

    2012-01-01

    and prognosis of patients. In this work we demonstrate a novel, centrifugally-driven microfluidic system for controlled manipulation of oligonucleotides and subsequent detection of chromosomal translocations. The device is fabricated in the form of a disc with capillary burst microvalves employed to control...

  9. 40 CFR 798.5460 - Rodent heritable translocation assays.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Rodent heritable translocation assays. 798.5460 Section 798.5460 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...) Species. The mouse is the species generally used, and is recommended. (ii) Age. Healthy sexually...

  10. Chromosome territories, X;Y translocation and Premature Ovarian Failure: is there a relationship?

    Directory of Open Access Journals (Sweden)

    Betri Enrico

    2009-09-01

    Full Text Available Abstract Background Premature ovarian failure (POF is a secondary hypergonadotrophic amenorrhea occurring before the age of 40 and affecting 1-3% of females. Chromosome anomalies account for 6-8% of POF cases, but only few cases are associated with translocations involving X and Y chromosomes. This study shows the cytogenetic and molecular analysis of a POF patient came to our attention as she developed a left ovary choriocarcinoma at the age of 10 and at 14 years of age she presented secondary amenorrhea with elevated levels of gonadotropins. Results Breakpoint position on X and Y chromosomes was investigated using Fluorescent In Situ Hybridisation (FISH with a panel of specific BAC probes, microsatellite analysis and evaluation of copy number changes and loss of heterozigosity by Affymetrix® GeneChip platform (Santa Clara, CA, USA. Patient's karyotype resulted 46, X, der(Yt(X;Y(q13.1;q11.223. X inactivation study was assessed by RBA banding and showed preferential inactivation of derivative chromosome. The reciprocal spatial disposition of sexual chromosome territories was investigated using whole chromosome painting and centromeres probes: patient's results didn't show a significant difference in comparison to normal controls. Conclusion The peculiar clinical case come to our attention highlighted the complexity of POF aetiology and of the translocation event, even if our results seem to exclude any effect on nuclear organisation. POF phenotype could be partially explained by skewed X chromosome inactivation that influences gene expression.

  11. Using multiplexed regulation of luciferase activity and GFP translocation to screen for FOXO modulators

    Directory of Open Access Journals (Sweden)

    Carnero Amancio

    2009-02-01

    Full Text Available Abstract Background Independent luciferase reporter assays and fluorescent translocation assays have been successfully used in drug discovery for several molecular targets. We developed U2transLUC, an assay system in which luciferase and fluorescent read-outs can be multiplexed to provide a powerful cell-based high content screening method. Results The U2transLUC system is based on a stable cell line expressing a GFP-tagged FOXO transcription factor and a luciferase reporter gene under the control of human FOXO-responsive enhancers. The U2transLUC assay measures nuclear-cytoplasmic FOXO shuttling and FOXO-driven transcription, providing a means to analyze these two key features of FOXO regulation in the same experiment. We challenged the U2transLUC system with chemical probes with known biological activities and we were able to identify compounds with translocation and/or transactivation capacity. Conclusion Combining different biological read-outs in a single cell line offers significant advantages over conventional cell-based assays. The U2transLUC assay facilitates the maintenance and monitoring of homogeneous FOXO transcription factor expression and allows the reporter gene activity measured to be normalized with respect to cell viability. U2transLUC is suitable for high throughput screening and can identify small molecules that interfere with FOXO signaling at different levels.

  12. Dietary nitrite improves insulin signaling through GLUT4 translocation.

    Science.gov (United States)

    Jiang, Hong; Torregrossa, Ashley C; Potts, Amy; Pierini, Dan; Aranke, Mayank; Garg, Harsha K; Bryan, Nathan S

    2014-02-01

    Diabetes mellitus type 2 is a syndrome of disordered metabolism with inappropriate hyperglycemia owing to a reduction in the biological effectiveness of insulin. Type 2 diabetes is associated with an impaired nitric oxide (NO) pathway that probably serves as the key link between metabolic disorders and cardiovascular disease. Insulin-mediated translocation of GLUT4 involves the PI3K/Akt kinase signal cascade that results in activation of endothelial NO synthase (eNOS). eNOS is dysfunctional during diabetes. We hypothesize that loss of eNOS-derived NO terminates the signaling cascade and therefore cannot activate GLUT4 translocation and that dietary nitrite may repair this pathway. In this study, we administered 50mg/L sodium nitrite to db/db diabetic mice for 4 weeks. After 4 weeks treatment, the db/db mice experienced less weight gain, improved fasting glucose levels, and reduced insulin levels. Cell culture experiments using CHO-HIRc-myc-GLUT4eGFP cell lines stably expressing insulin receptor and myc-GLUT4eGFP protein, as well as L6 skeletal muscle cells stably expressing rat GLUT4 with a Myc epitope (L6-GLUT4myc), showed that NO, nitrite, and GSNO stimulate GLUT4 translocation independent of insulin, which is inhibited by NEM. Collectively our data suggest that nitrite improves insulin signaling through restoration of NO-dependent nitrosation of GLUT4 signaling translocation. These data suggest that NO-mediated nitrosation of GLUT4 by nitrite or other nitrosating agents is necessary and sufficient for GLUT4 translocation in target tissue. Description of this pathway may justify a high-nitrate/nitrite diet along with the glycemic index to provide a safe and nutritional regimen for the management and treatment of diabetes.

  13. Low background infrared (LBIR) facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Low background infrared (LBIR) facility was originally designed to calibrate user supplied blackbody sources and to characterize low-background IR detectors and...

  14. Biosecurity for Translocations: Cirl Bunting (Emberiza cirlus), Fisher's Estuarine Moth (Gortyna borelii lunata), Short-Haired Bumblebee (Bombus subterraneus) and Pool Frog (Pelophylax lessonae) Translocations as Case Studies.

    Science.gov (United States)

    Vaughan-Higgins, R J; Masters, N; Sainsbury, A W

    2016-08-04

    Exposure to parasites in conservation translocations increases the risks to recipient and translocated populations from disease, and therefore there has been interest in implementing biosecurity methods. Using four case examples we described how biosecurity was applied in practical translocation scenarios prior to and during a translocation and also post-release. We implemented biosecurity, including quarantine barriers, at specific points in the translocation pathway where hazards, identified by the disease risk analysis, had the potential to induce disease. Evidence that biosecurity protected translocated and recipient populations, included an absence of mortality associated with high-risk non-native parasites, a reduction in mortality associated with endemic parasites, the absence of high-risk pathogenic parasites, or associated diseases, at the destination; and the apparent absence of diseases in closely related species at the destination site. The biosecurity protocols did not alter the level or duration of translocated species confinement and therefore probably did not act as a stressor. There is a monetary cost involved in biosecurity but the epidemiological evidence suggests that conservation translocation managers should carefully consider its use. Breakdowns in quarantine have occurred in human hospitals despite considerable investment and training for health professionals, and we therefore judge that there is a need for training in the objectives and maintenance of quarantine barriers in conservation translocations. Biosecurity protocols for conservation translocations should be continually updated in response to findings from disease risk analysis and post-release disease surveillance and we recommend further studies to evaluate their effectiveness.

  15. Cosmic Microwave Background Mapping

    Science.gov (United States)

    Verkhodanov, O. V.; Doroshkevich, A. G.

    2012-03-01

    The last decade of research in cosmology was connected with the ambitious experiments including space and ground base observations. Among the most impressive results of these investigations are the measurements of the cosmic microwave background (CMB) radiation like WMAP* and Planck. Exactly from the CMB studies, we have started the epoch of the precision cosmology when generally the values of cosmological parameters have been known and present research is devoted to improvement of the precision. These achievements are connected with both the creation of the new facilities in millimeter and submillimeter astronomy (e.g., satellites, receivers, antennas, computers) and development of the methods for the CMB data analysis. Actually, the process of data analysis contains several technical stages including 1. Registration of time-ordered data (TOD) 2. Pixelization of the CMB data - map preparation 3. Component separation 4. Map statistics analysis 5. Map - spherical harmonics transformation 6. C(l)-spectrum calculation and spectrum statistics analysis 7. Cosmological parameters estimation Starting from the cosmic background explorer (COBE) experiment using the so-called Quadrilateralized Sky Cube Projection (see [1-3]), the problem of the whole sky CMB pixelization has attracted great interest and many such schemes were developed. Let us note however that accurate pixelization of the CMB data on the sphere is very important but not the final step of analysis. Usually, the next step implies the determination of the coefficients of the spherical harmonic decomposition of the CMB signal for both anisotropy and polarization. This means that some of the pixelization schemes provide a very accurate map but are inconvenient for further decomposition. This also means that the choice of suitable pixelization schemes depends upon the general goals of the investigation. In this review, we consider several of the most popular sky map pixelization schemes and link them with the

  16. Microbial Translocation in HIV Infection is Associated with Dyslipidemia, Insulin Resistance, and Risk of Myocardial Infarction

    DEFF Research Database (Denmark)

    Pedersen, Karin Kaereby; Pedersen, Maria; Trøseid, Marius;

    2013-01-01

    Microbial translocation has been suggested to be a driver of immune activation and inflammation. We hypothesized that microbial translocation may be related to dyslipidemia, insulin resistance, and the risk of coronary heart disease in HIV-infected individuals....

  17. Background and introduction

    DEFF Research Database (Denmark)

    2012-01-01

    Purpose: To explain the purpose and background of this book and introduce the three basic perspectives behind the research presented as well as the structure and editing process of the book. Methodology: The editors shared and discussed individual contributions to this chapter, based on their own...... behind the scenes of the making of this book and connects contributions from three different fields - FM, CREM, and B2B marketing - to shed more light on the concept of added value of FM. It serves as an introduction to the research presented in the other chapters in this book....... expertise, the involvement in the process leading to this the book including a number of workshops, and a literature review of the development of their disciplinary fields: Facilities Management (FM), Corporate Real Estate Management (CREM) and Business to Business (B2B) Marketing. Findings: The difference...... in scope between FM and CREM is that CREM has its focus on real estate as physical and economical assets utilized by an organisation, while FM has a wider service focus. The difference in scope between FM and CREM on one side and B2B marketing on the other is that FM and CREM are related to organisations...

  18. DCCD inhibits protein translocation into plasma membrane vesicles from Escherichia coli at two different steps.

    OpenAIRE

    1987-01-01

    In vitro translocation of periplasmic and outer membrane proteins into inverted plasma membrane vesicles from Escherichia coli was completely prevented by the H+-ATPase inhibitor N,N'-dicyclohexylcarbodiimide (DCCD). DCCD was inhibitory to both co- and post-translational translocations, suggesting an involvement of the H+-translocating F1F0-ATPase in either mode of transport. This was verified by (i) the dependence of efficient co-translational translocation upon a low salt, i.e. F1-containin...

  19. Meiotic behaviour and spermatogenesis in male mice heterozygous for translocation types also occurring in man

    NARCIS (Netherlands)

    Nijhoff, J.H.

    1981-01-01

    In this thesis a start was made with meiotic observations of mouse translocation types - a Robertsonian translocation and a translocation between a metacentric and an acrocentric chromosome - which also occur in man. It is generally accepted that, when no chromosomal rearrangements are involved, man

  20. Frequency standards

    CERN Document Server

    Riehle, Fritz

    2006-01-01

    Of all measurement units, frequency is the one that may be determined with the highest degree of accuracy. It equally allows precise measurements of other physical and technical quantities, whenever they can be measured in terms of frequency.This volume covers the central methods and techniques relevant for frequency standards developed in physics, electronics, quantum electronics, and statistics. After a review of the basic principles, the book looks at the realisation of commonly used components. It then continues with the description and characterisation of important frequency standards

  1. Role of granulocyte colony-stimulating factor in paclitaxel-induced intestinal barrier breakdown and bacterial translocation in rats

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chi; XU Yang-guang; DUAN Xue-ning; LIU Yin-hua; ZHAO Jian-xin; XU Ling; YE Jing-ming

    2011-01-01

    Background Chemotherapy causes breakdown of the intestinal barrier, which may lead to bacterial translocation. Paclitaxel, an anti-tubulin agent, has many side effects; however, its effect on the intestinal barrier is unknown. Previous studies show that granulocyte colony-stimulating factor (G-CSF) plays an important role in modulating intestinal barrier function, but these studies are not conclusive. Here, we investigated the effects of paclitaxel on the intestinal barrier, and whether G-CSF could prevent paclitaxel-induced bacterial translocation.Methods Twenty-four male Sprague-Dawley rats were divided into three groups: control group, paclitaxel group and paclitaxel + G-CSF group. Intestinal permeability was measured by the urinary excretion rates of lactulose and mannitol administered by gavage. The mesenteric lymph nodes, spleen and liver were aseptically harvested for bacterial culture. Endotoxin levels and white blood cell (WBC) counts were measured and bacterial quantification performed using relative real-time PCR. Jejunum samples were also obtained for histological observation. Intestinal apoptosis was evaluated using a fragmented DNA assay and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP)-biotin nick end-labeling staining. One-way analysis of variance and Fisher's exact test were used to compare differences between groups.Results Paclitaxel induced apoptosis in 12.5% of jejunum villus cells, which was reduced to 3.8% by G-CSF treatment. Apoptosis in the control group was 0.6%. Paclitaxel treatment also resulted in villus atrophy, increased intestinal permeability and a reduction in the WBC count. G-CSF treatment resulted in increased villus height and returned WBC counts to normal levels. No bacterial translocation was detected in the control group, whereas 6/8,8/8, and 8/8 rats in the paclitaxel group were culture-positive in the liver, spleen and mesenteric lymph nodes, respectively. Bacterial translocation was

  2. Silibinin induces apoptosis via calpain-dependent AIF nuclear translocation in U87MG human glioma cell death

    Directory of Open Access Journals (Sweden)

    Kim Yong K

    2011-04-01

    Full Text Available Abstract Background Silibinin, a natural polyphenolic flavonoid, has been reported to induce cell death in various cancer cell types. However, the molecular mechanism is not clearly defined. Our previous study showed that silibinin induces glioma cell death and its effect was effectively prevented by calpain inhibitor. The present study was therefore undertaken to examine the role of calpain in the silibinin-induced glioma cell death. Methods U87MG cells were grown on well tissue culture plates and cell viability was measured by MTT assay. ROS generation and △ψm were estimated using the fluorescence dyes. PKC activation and Bax expression were measured by Western blot analysis. AIF nuclear translocation was determined by Western blot and immunocytochemistry. Results Silibinin induced activation of calpain, which was blocked by EGTA and the calpain inhibitor Z-Leu-Leu-CHO. Silibinin caused ROS generation and its effect was inhibited by calpain inhibitor, the general PKC inhibitor GF 109203X, the specific PKCδ inhibitor rottlerin, and catalase. Silibinin-induce cell death was blocked by calpain inhibitor and PKC inhibitors. Silibinin-induced PKCδ activation and disruption of △ψm were prevented by the calpain inhibitor. Silibinin induced AIF nuclear translocation and its effect was prevented by calpain inhibitor. Transfection of vector expressing microRNA of AIF prevented the silibinin-induced cell death. Conclusions Silibinin induces apoptotic cell death through a calpain-dependent mechanism involving PKC, ROS, and AIF nuclear translocation in U87MG human glioma cells.

  3. Frequency synthesiser

    NARCIS (Netherlands)

    Drago, Salvatore; Sebastiano, Fabio; Leenaerts, Dominicus Martinus Wilhelmus; Breems, Lucien Johannes; Nauta, Bram

    2016-01-01

    A low power frequency synthesiser circuit (30) for a radio transceiver, the synthesiser circuit comprising: a digital controlled oscillator configured to generate an output signal having a frequency controlled by an input digital control word (DCW); a feedback loop connected between an output and an

  4. Cosmic Microwave Background Data Analysis

    Science.gov (United States)

    Paykari, Paniez; Starck, Jean-Luc Starck

    2012-03-01

    About 400,000 years after the Big Bang the temperature of the Universe fell to about a few thousand degrees. As a result, the previously free electrons and protons combined and the Universe became neutral. This released a radiation which we now observe as the cosmic microwave background (CMB). The tiny fluctuations* in the temperature and polarization of the CMB carry a wealth of cosmological information. These so-called temperature anisotropies were predicted as the imprints of the initial density perturbations which gave rise to the present large-scale structures such as galaxies and clusters of galaxies. This relation between the present-day Universe and its initial conditions has made the CMB radiation one of the most preferred tools to understand the history of the Universe. The CMB radiation was discovered by radio astronomers Arno Penzias and Robert Wilson in 1965 [72] and earned them the 1978 Nobel Prize. This discovery was in support of the Big Bang theory and ruled out the only other available theory at that time - the steady-state theory. The crucial observations of the CMB radiation were made by the Far-Infrared Absolute Spectrophotometer (FIRAS) instrument on the Cosmic Background Explorer (COBE) satellite [86]- orbited in 1989-1996. COBE made the most accurate measurements of the CMB frequency spectrum and confirmed it as being a black-body to within experimental limits. This made the CMB spectrum the most precisely measured black-body spectrum in nature. The CMB has a thermal black-body spectrum at a temperature of 2.725 K: the spectrum peaks in the microwave range frequency of 160.2 GHz, corresponding to a 1.9mmwavelength. The results of COBE inspired a series of ground- and balloon-based experiments, which measured CMB anisotropies on smaller scales over the next decade. During the 1990s, the first acoustic peak of the CMB power spectrum (see Figure 5.1) was measured with increasing sensitivity and by 2000 the BOOMERanG experiment [26] reported

  5. Optimised spectral merge of the background model in seismic inversion

    Science.gov (United States)

    White, Roy; Zabihi Naeini, Ehsan

    2017-01-01

    The inversion of seismic reflection data to absolute impedance generates low-frequency deviations around the true impedance if the frequency content of the background impedance model does not merge seamlessly into the spectrum of the inverted seismic data. We present a systematic method of selecting a background model that minimises the mismatch between the background model and the relative impedance obtained by inverting the seismic data at wells. At each well a set of well-log relative impedances is formed by passing the impedance log through a set of zero-phase high-pass filters. The corresponding background models are constructed by passing the impedance log through the complementary zero-phase low-pass filters and a set of seismic relative impedances is computed by inverting the seismic data using these background models. If the inverted seismic data is to merge perfectly with the background model, it should correspond at the well to the well-log relative impedance. This correspondence is the basis of a procedure for finding the optimum combination of background model and inverted seismic data. It is difficult to predict the low-frequency content of inverted seismic data. These low frequencies are affected by the uncertainties in (1) measuring the low-frequency response of the seismic wavelet and (2) knowing how inversion protects the signal-to-noise ratio at low frequencies. Uncertainty (1) becomes acute for broadband seismic data; the low-frequency phase is especially difficult to estimate. Moreover we show that a mismatch of low-frequency phase is a serious source of inversion artefacts. We also show that relative impedance can estimate the low-frequency phase where a well tie cannot. Consequently we include a low-frequency phase shift, applied to the seismic relative impedances, in the search for the best spectral merge. The background models are specified by a low-cut corner frequency and the phase shifts by a phase intercept at zero frequency. A scan of

  6. Cross correlations of the cosmic infrared background

    CERN Document Server

    Zhang, P

    2003-01-01

    Cosmic infrared background (CIB) is a sensitive measure of the structure formation of the universe, especially the star formation history. But this background is overwhelmed by foregrounds. The cross correlation of CIB with galaxies is able to eliminate such foregrounds, minimize and localize several backgrounds which could bias the study of the star formation history. The cross correlation study of CIB has three advantages. (1) Combining the galaxy photometric redshift information, it directly measures the structure formation history. (2) The sky area used for CIB analysis is no long limited to the relatively clean sky. The utilization of CIB full sky data minimizes the sample variance. (3) The CIB measurement is no longer limited to several narrow frequency windows. This allows the measurement of CIB based on integrated intensity, whose theoretical prediction is based on energy conservation, thus is fairly model independent and robust. The cross correlation can be measured with 10% accuracy (statistical and...

  7. Gut flora and bacterial translocation in chronic liver disease

    Institute of Scientific and Technical Information of China (English)

    John Almeida; Sumedha Galhenage; Jennifer Yu; Jelica Kurtovic; Stephen M Riordan

    2006-01-01

    Increasing evidence suggests that derangement of gut flora is of substantial clinical relevance to patients with cirrhosis. Intestinal bacterial overgrowth and increased bacterial translocation of gut flora from the intestinal lumen, in particular, predispose to an increased potential for bacterial infection in this group. Recent studies suggest that, in addition to their role in the pathogenesis of overt infective episodes and the clinical consequences of sepsis, gut flora contributes to the pro-inflammatory state of cirrhosis even in the absence of overt infection.Furthermore, manipulation of gut flora to augment the intestinal content of lactic acid-type bacteria at the expense of other gut flora species with more pathogenic potential may favourably influence liver function in cirrhotic patients. Here we review current concepts of the various inter-relationships between gut flora, bacterial translocation, bacterial infection, pro-inflammatory cytokine production and liver function in this group.

  8. Studying DNA translocation in nanocapillaries using single molecule fluorescence

    CERN Document Server

    Thacker, Vivek V; Hernández-Ainsa, Silvia; Bell, Nicholas A W; Keyser, Ulrich F; 10.1063/1.4768929

    2013-01-01

    We demonstrate simultaneous measurements of DNA translocation into glass nanopores using ionic current detection and fluorescent imaging. We verify the correspondence between the passage of a single DNA molecule through the nanopore and the accompanying characteristic ionic current blockage. By tracking the motion of individual DNA molecules in the nanocapillary perpendicular to the optical axis and using a model, we can extract an effective mobility constant for DNA in our geometry under high electric fields.

  9. The pathological effect of bacterial translocation to the Henssge Nomogram

    OpenAIRE

    Ivanka, Ján

    2012-01-01

    This article presents the results of measurements of the influence of pathological bacterial translocation on the intestinal wall of the area, measured per recta, and its influence on the course of a Henssge Nomogram. The gram-positive /negative bacteria which influence temperature measurements and the subsequent regressive non-stationary temperature data of biological objects when establishing the moment of death are described in a lucid, synoptic form. Based upon forensic praxis, profession...

  10. Particles translocate from the vagina to the oviducts and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Wehner, A.P.; Hall, A.S.; Weller, R.E.; Lepel, E.A.; Schirmer, R.E.

    1985-03-01

    To investigate whether particles deposited in the vagina translocate to the oviducts, 0.3 ml of a 4% bone black suspension was deposited in the posterior vaginal fornix of each of five cynomolgus monkeys (Macaca fascicularis) during their mid-menstrual cycle. Simultaneously, each animal received 10 units of oxytocin by intramuscular injection. The oviducts of three animals were removed 1 hr after administration of the bone black, while those of the remaining two animals were removed 72 hr after dosing. The removed oviducts were flushed with Hank's solution and then with collagenase solution. The solutions were collected in clean vials and filtered. The filters were examined for bone black particles by light microscopy, as were filters through which solution blanks (negative controls) had been passed. Particles resembling bone black were found on all filters. There were no appreciable differences in the number or shape of these particles between the solution-blank filters and the oviduct-flush filters. The particles on both the solution-blank filters and on the oviduct-flush filters probably originated from environmental contamination by ubiquitous carbon particles. While these results suggested that no translocation took place, translocation could not be ruled out with certainty in the absence of quantitative analyses. A more definitive pilot study was then conducted with two dosed monkeys and one control, using talc labelled by neutron activation to circumvent the problem of environmental contamination. Gamma-Ray analysis of tissue and peritoneal lavage samples for the radionuclides /sup 46/Sc, /sup 59/Fe and /sup 60/Co indicated that no measurable quantities (i.e. greater than 0.5 micrograms) of talc translocated from the deposition site in the vagina to the uterine cavity and beyond.

  11. Subcellular distribution and translocation of radionuclides in plants

    Energy Technology Data Exchange (ETDEWEB)

    Gouthu, S.; Weginwar, R.; Arie, Tsutomu; Ambe, Shizuko; Ozaki, Takuo; Enomoto, Shuichi; Ambe, Fumitoshi; Yamaguchi, Isamu

    1999-09-01

    The subcellular distribution of radionuclides in Glycine max Merr. (soybean) and Cucumis sativus L. (cucumber) and translocation of plant absorbed radionuclides with growth in soybean were studied. More than 60% of cellular incorporated Rb{sup {minus}83}, Sr{sup {minus}85}, Mn{sup {minus}54}, Nb{sup {minus}95}, and Se{sup {minus}75} remained in the supernatant fraction; 55% and 20% of Cr{sup {minus}51} was bound to soybean and cucumber cell wall fractions, respectively; 70% or more of Be{sup {minus}7}, Y{sup {minus}88}, and Fe{sup {minus}59} was fixed in the chloroplast fraction; and approx. 10% of Sc{sup {minus}46}, Fe{sup {minus}59}, V{sup {minus}48}, and As were fixed in the mitochondrial fraction. Translocation of nuclides within the soybean plant at different stages of growth has been determined. Vanadium, Y{sup {minus}88}, Be{sup {minus}7}, Se{sup {minus}75}, Nb{sup {minus}95}, Sc{sup {minus}46}, Cr{sup {minus}51}, and Zr{sup {minus}88} were predominantly accumulated in the root. Although the total percentage of plant uptake of Sc{sup {minus}46}, Zr{sup {minus}88}, Nb{sup {minus}95}, Sc{sup {minus}46}, and Cr{sup {minus}51} was high, because of low mobility and translocation to shoot, their accumulation in the fruit fraction was negligible. The translocation of mobile nuclides in plants was demonstrated clearly by Rb{sup {minus}83}, Zn{sup {minus}65}, and Fe{sup {minus}59}. Data on the nuclide fraction mobilized from vegetative parts into edible parts was used to assess the percentage of accumulated radionuclides in plants that may reach humans through beans.

  12. "Translocal Express" juba täna! / Rael Artel

    Index Scriptorium Estoniae

    Artel, Rael, 1980-

    2009-01-01

    27. märtsil algab Kumu Kunstimuuseumis "Public Preparation'i" ("Avalik ettevalmistus") sarja rahvusvaheline seminar "Translocal Express. Golden Age" ("Translokaalne ekspress. Kuldaeg"), kus on kõne all ajalookirjutamise ja kollektiivse mälu roll praegu domineerivas natsionalistlikus diskursuses ja selle käsitlemine kaasaegses kunstis. Seminaril on lähtutud eelkõige kunstnike Martin Krenni (Viin) ja Kristina Normani teoste tutvustamisest

  13. Biomarkers of inflammation, coagulation and microbial translocation in HIV/HCV co-infected patients in the SMART study

    DEFF Research Database (Denmark)

    Peters, Lars; Neuhaus, Jacqueline; Duprez, Daniel;

    2014-01-01

    BACKGROUND: Previous results from the SMART study showed that HIV/viral hepatitis co-infected persons with impaired liver function are at increased risk of death following interruption of antiretroviral therapy (ART). OBJECTIVES: To investigate the influence of fibrosis and ART interruption...... on levels of biomarkers of inflammation, coagulation and microbial translocation in HIV/HCV co-infected persons in the SMART study. STUDY DESIGN: All HIV/HCV co-infected persons with stored plasma at study entry and at six months of follow-up were included (N=362). D-dimer, IL-6, sCD14 and hepatic...

  14. Low translocation of Bacillus thuringiensis israelensis to inner organs in mice after pulmonary exposure to commercial biopesticide

    DEFF Research Database (Denmark)

    Barfod, Kenneth Klingenberg; Ørum-Smidt, Lasse; Krogfelt, Karen A.;

    2010-01-01

    Translocation of viable cells from a Bacillus thuringiensis israelensis-based biopesticide to inner organs in a mouse model was studied. Mice were exposed to the originally formulated product through the lungs and gastrointestinal tract by intratracheal instillation. Colony forming units (CFU) were...... grown from lungs, caecum, spleen and liver on Bacillus cereus-specific agar (BCSA) after 24 h and finally determined to be biopesticide strain B. t. israelensis by large plasmid profile. No CFU were found in spleen or liver of the control mice or in any aerosol background or material. We have shown...

  15. Black bears in Arkansas: Characteristics of a successful translocation

    Science.gov (United States)

    Smith, Kimberly G.; Clark, Joseph D.

    1994-01-01

    In 1958, the Arkansas Game and Fish Commission began translocating black bears (Ursus americanus) from Minnesota to the Interior Highlands (Ozark and Ouachita mountains) of Arkansas where bears had been extirpated early in this century. This project continued for 11 years with little public imput, during which time an estimated 254 bears were released. We estimate there are now >2,500 bears in the Interior Highlands of Arkansas, Missouri, and Oklahoma, making it one of the most successful translocations of a Carnivora. Factors that contributed to the success include use of wild-captured animals, elimination of major factors associated with extirpation, release into prime habitats within the former range, multiple release sites, release of 20–40 animals/year for eight years, and release of mostly males prior to release of mostly females. Studies on two allopatric populations demonstrate that they are now diverging in some demographic characteristics, including litter size, cub survivorship, and adult sex-ratio. Translocation of black bears to the Interior Highlands is successful in terms of numbers of animals, but it will not be truly successful until people accept black bears as part of the regional fauna. To that end, those associated with management and research of bears in Arkansas are now focussing on public education and control of nuisance bears.

  16. Dominant-lethal mutations and heritable translocations in mice

    Energy Technology Data Exchange (ETDEWEB)

    Generoso, W.M.

    1983-01-01

    Chromosome aberrations are a major component of radiation or chemically induced genetic damage in mammalian germ cells. The types of aberration produced are dependent upon the mutagen used and the germ-cell stage treated. For example, in male meiotic and postmeiotic germ cells certain alkylating chemicals induce both dominant-lethal mutations and heritable translocations while others induce primarily dominant-lethal mutations. Production of these two endpoints appears to be determined by the stability of alkylation products with the chromosomes. If the reaction products are intact in the male chromosomes at the time of sperm entry, they may be repaired in fertilized eggs. If repair is not effected and the alkylation products persist to the time of pronuclear chromosome replication, they lead to chromatid-type aberrations and eventually to dominant-lethality. The production of heritable translocations, on the other hand, requires a transformation of unstable alkylation products into suitable intermediate lesions. The process by which these lesions are converted into chromosome exchange within the male genome takes place after sperm enters the egg but prior to the time of pronuclear chromosome replication (i.e., chromosome-type). Thus, dominant-lethal mutations result from both chromatid- and chromosome-type aberrations while heritable translocations result primarily from the latter type. DNA target sites associated with the production of these two endpoints are discussed.

  17. Detection of Kinase Translocation Using Microfluidic Electroporative Flow Cytometry

    Science.gov (United States)

    Lu, Chang; Wang, Jun; Bao, Ning; Paris, Leela; Wang, Hsiang-Yu; Geahlen, Robert

    2008-03-01

    Translocation of a protein between different subcellular compartments is a common event during signal transduction in living cells. Detection of these events has been largely carried out based on imaging of a low number of cells and subcellular fractionation/Western blotting. These conventional techniques either lack the high throughput desired for probing an entire cell population or provide only the average behaviors of cell populations without information from single cells. Here we demonstrate a new tool, referred to as microfluidic electroporative flow cytometry, to detect the translocation of an EGFP-tagged tyrosine kinase, Syk, to the plasma membrane in B cells at the level of the cell population. We combine electroporation with flow cytometry and observe the release of intracellular kinase out of the cells during electroporation. We found that the release of the kinase was strongly influenced by its subcellular localization. Cells stimulated through the antigen receptor have a fraction of the kinase at the plasma membrane and retain more kinase after electroporation than do cells without stimulation and translocation. This tool will have utility for kinase-related drug discovery and tumor diagnosis and staging.

  18. DegP Chaperone Suppresses Toxic Inner Membrane Translocation Intermediates

    Science.gov (United States)

    Braselmann, Esther; Chaney, Julie L.; Champion, Matthew M.

    2016-01-01

    The periplasm of Gram-negative bacteria includes a variety of molecular chaperones that shepherd the folding and targeting of secreted proteins. A central player of this quality control network is DegP, a protease also suggested to have a chaperone function. We serendipitously discovered that production of the Bordetella pertussis autotransporter virulence protein pertactin is lethal in Escherichia coli ΔdegP strains. We investigated specific contributions of DegP to secretion of pertactin as a model system to test the functions of DegP in vivo. The DegP chaperone activity was sufficient to restore growth during pertactin production. This chaperone dependency could be relieved by changing the pertactin signal sequence: an E. coli signal sequence leading to co-translational inner membrane (IM) translocation was sufficient to suppress lethality in the absence of DegP, whereas an E. coli post-translational signal sequence was sufficient to recapitulate the lethal phenotype. These results identify a novel connection between the DegP chaperone and the mechanism used to translocate a protein across the IM. Lethality coincided with loss of periplasmic proteins, soluble σE, and proteins regulated by this essential stress response. These results suggest post-translational IM translocation can lead to the formation of toxic periplasmic folding intermediates, which DegP can suppress. PMID:27626276

  19. DegP Chaperone Suppresses Toxic Inner Membrane Translocation Intermediates.

    Science.gov (United States)

    Braselmann, Esther; Chaney, Julie L; Champion, Matthew M; Clark, Patricia L

    2016-01-01

    The periplasm of Gram-negative bacteria includes a variety of molecular chaperones that shepherd the folding and targeting of secreted proteins. A central player of this quality control network is DegP, a protease also suggested to have a chaperone function. We serendipitously discovered that production of the Bordetella pertussis autotransporter virulence protein pertactin is lethal in Escherichia coli ΔdegP strains. We investigated specific contributions of DegP to secretion of pertactin as a model system to test the functions of DegP in vivo. The DegP chaperone activity was sufficient to restore growth during pertactin production. This chaperone dependency could be relieved by changing the pertactin signal sequence: an E. coli signal sequence leading to co-translational inner membrane (IM) translocation was sufficient to suppress lethality in the absence of DegP, whereas an E. coli post-translational signal sequence was sufficient to recapitulate the lethal phenotype. These results identify a novel connection between the DegP chaperone and the mechanism used to translocate a protein across the IM. Lethality coincided with loss of periplasmic proteins, soluble σE, and proteins regulated by this essential stress response. These results suggest post-translational IM translocation can lead to the formation of toxic periplasmic folding intermediates, which DegP can suppress.

  20. Patch-clamp detection of macromolecular translocation along nuclear pores

    Directory of Open Access Journals (Sweden)

    Bustamante J.O.

    1998-01-01

    Full Text Available The present paper reviews the application of patch-clamp principles to the detection and measurement of macromolecular translocation along the nuclear pores. We demonstrate that the tight-seal 'gigaseal' between the pipette tip and the nuclear membrane is possible in the presence of fully operational nuclear pores. We show that the ability to form a gigaseal in nucleus-attached configurations does not mean that only the activity of channels from the outer membrane of the nuclear envelope can be detected. Instead, we show that, in the presence of fully operational nuclear pores, it is likely that the large-conductance ion channel activity recorded derives from the nuclear pores. We conclude the technical section with the suggestion that the best way to demonstrate that the nuclear pores are responsible for ion channel activity is by showing with fluorescence microscopy the nuclear translocation of ions and small molecules and the exclusion of the same from the cisterna enclosed by the two membranes of the envelope. Since transcription factors and mRNAs, two major groups of nuclear macromolecules, use nuclear pores to enter and exit the nucleus and play essential roles in the control of gene activity and expression, this review should be useful to cell and molecular biologists interested in understanding how patch-clamp can be used to quantitate the translocation of such macromolecules into and out of the nucleus

  1. Growth factor deprivation induces cytosolic translocation of SIRT1

    Science.gov (United States)

    Meng, Chengbo; Xing, Da; Wu, Shengnan; Huang, Lei

    2010-02-01

    Sirtuin type 1 (SIRT1), a NAD+-dependent histone deacetylases, plays a critical role in cellular senescence, aging and longevity. In general, SIRT1 is localized in nucleus and is believed as a nuclear protein. Though overexpression of SIRT1 delays senescence, SIRT1-protein levels decline naturally in thymus and heart during aging. In the present studies, we investigated the subcellular localization of SIRT1 in response to growth factor deprivation in African green monkey SV40-transformed kidney fibroblast cells (COS-7). Using SIRT1-EGFP fluorescence reporter, we found that SIRT1 localized to nucleus in physiological conditions. We devised a model enabling cell senescence via growth factor deprivation, and we found that SIRT1 partially translocated to cytosol under the treatment, suggesting a reduced level of SIRT1's activity. We found PI3K/Akt pathway was involved in the inhibition of SIRT1's cytosolic translocation, because inhibition of these kinases significantly decreased the amount of SIRT1 maintained in nucleus. Taken together, we demonstrated that growth factor deprivation induces cytosolic translocation of SIRT1, which suggesting a possible connection between cytoplasm-localized SIRT1 and the aging process.

  2. Single Nanoparticle Translocation Through Chemically Modified Solid Nanopore

    Science.gov (United States)

    Tan, Shengwei; Wang, Lei; Liu, Hang; Wu, Hongwen; Liu, Quanjun

    2016-02-01

    The nanopore sensor as a high-throughput and low-cost technology can detect single nanoparticle in solution. In the present study, the silicon nitride nanopores were fabricated by focused Ga ion beam (FIB), and the surface was functionalized with 3-aminopropyltriethoxysilane to change its surface charge density. The positively charged nanopore surface attracted negatively charged nanoparticles when they were in the vicinity of the nanopore. And, nanoparticle translocation speed was slowed down to obtain a clear and deterministic signal. Compared with previous studied small nanoparticles, the electrophoretic translocation of negatively charged polystyrene (PS) nanoparticles (diameter ~100 nm) was investigated in solution using the Coulter counter principle in which the time-dependent nanopore current was recorded as the nanoparticles were driven across the nanopore. A linear dependence was found between current drop and biased voltage. An exponentially decaying function ( t d ~ e -v/v0 ) was found between the duration time and biased voltage. The interaction between the amine-functionalized nanopore wall and PS microspheres was discussed while translating PS microspheres. We explored also translocations of PS microspheres through amine-functionalized solid-state nanopores by varying the solution pH (5.4, 7.0, and 10.0) with 0.02 M potassium chloride (KCl). Surface functionalization showed to provide a useful step to fine-tune the surface property, which can selectively transport molecules or particles. This approach is likely to be applied to gene sequencing.

  3. Spatial behaviour and survival of translocated wild brown hares

    Directory of Open Access Journals (Sweden)

    Fischer, C.

    2012-01-01

    Full Text Available The fragility of many populations of brown hares in Western Europe is a concern for managers, hunters and naturalists. We took advantage of a locally high density population to use wild individuals to restock areas where the species had disappeared or was close to disappearing. The aim of the project was to assess the evolution of the spatial behaviour after release using radio–tracking. Over 150 wild brown hares were translocated, one third of which were fitted with radio collars. In addition, fifteen individuals were radio–tagged and released back into the source population as a control. Most individuals settled in less than two months and their seasonal home range, once settled, was similar to that observed in the source population. Mean duration of tracking was not significantly different between the two groups. Moreover, two years after the last translocation, tagged individuals can still be observed, but most hares present are not tagged, which indicates natural reproduction of the released individuals. The translocation of wild individuals thus appears to give encouraging results.

  4. Growth hormone reduces mortality and bacterial translocation in irradiated rats

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-de-Segura, I.A.; Miguel, E. de [`La Paz` Hospital, Madrid (Spain). Dept. of Experimental Surgery; Prieto, I. [`La Paz` Hospital, Madrid (Spain). Dept. of General and Digestive Surgery; Grande, A.G. [`La Paz` Hospital, Madrid (Spain). Dept. of Oncology Radiotherapy; Garcia, P.; Mendez, J. [`La Paz` Hospital, Madrid (Spain). Dept. of Clinical Biochemistry; Guerra, A. [`La Paz` Hospital, Madrid (Spain). Dept. of Microbiology

    1998-09-01

    Growth hormone stimulates the growth of intestinal mucosa and may reduce the severity of injury caused by radiation. Male Wistar rats underwent abdominal irradiation (12 Gy) and were treated with either human growth hormone (hGH) or saline, and sacrificed at day 4 or 7 post-irradiation. Bacterial translocation, and the ileal mucosal thickness, proliferation, and disaccharidase activity were assessed. Mortality was 65% in irradiated animals, whereas hGH caused a decrement (29%, p<0.05). Bacterial translocation was also reduced by hGH (p<0.05). Treating irradiated rats with hGH prevented body weight loss (p<0.05). Mucosal thickness increased faster in irradiated hGH-treated animals. The proliferative index showed an increment in hGH-treated animals (p<0.05). Giving hGH to irradiated rats prevented decrease in sucrose activity, and increment in lactase activity. In conclusion, giving hGH to irradiated rats promotes the adaptative process of the intestine and acute radiation-related negative effects, including mortality, bacterial translocation, and weight loss. (orig.)

  5. Dieldrin uptake and translocation in plants growing in hydroponic medium.

    Science.gov (United States)

    Murano, Hirotatsu; Otani, Takashi; Seike, Nobuyasu; Sakai, Mizuki

    2010-01-01

    It has been known that the Cucurbitaceae family takes up a large amount of persistent organic pollutants from soils and that the translocation of those compounds in cucurbits is higher than those in non-cucurbits. To understand the persistent organic pollutant uptake mechanisms of plant species, we compared the dieldrin absorption and transportation potentials of several plants in hydroponic medium. Sorghum (Sorghum vulgare Moench), sunflower (Helianthus annuus L.), soybean (Glycine max), komatsuna (Brassica rapa var. peruviridis), white-flowered gourd (Lagenaria siceraria var. hispida), cucumber (Cucumis sativus L.), and zucchini (Cucurbita pepo L.) were grown in a dieldrin-added hydroponic medium for 10 d, and then the amount of dieldrin in their shoots and roots was measured. All of the roots contained dieldrin, whereas only the cucurbits (white-flowered gourd, cucumber, and zucchini) contained considerable amounts of dieldrin in their shoots. The dieldrin uptake to the roots depended on the concentration of the n-hexane soluble components in the roots, regardless of whether the dieldrin in the roots was translocated to shoots or not. The dieldrin uptake from the solution to the roots was thought to be due to a passive response, such as adsorption on the roots. The translocation of dieldrin from the roots to the shoots was probably through the xylems. The amounts of dieldrin in the shoots per transpiration rates were higher for cucurbits than for non-cucurbits. It seems likely that cucurbits have uptake mechanisms for hydrophobic organic chemicals.

  6. Gq-mediated Akt translocation to the membrane: a novel PIP3-independent mechanism in platelets.

    Science.gov (United States)

    Badolia, Rachit; Manne, Bhanu Kanth; Dangelmaier, Carol; Chernoff, Jonathan; Kunapuli, Satya P

    2015-01-01

    Akt is an important signaling molecule regulating platelet aggregation. Akt is phosphorylated after translocation to the membrane through Gi signaling pathways by a phosphatidylinositol-3,4,5-trisphosphate (PIP3)-dependent mechanism. However, Akt is more robustly phosphorylated by thrombin compared with adenosine 5'-diphosphate in platelets. This study investigated the mechanisms of Akt translocation as a possible explanation for this difference. Stimulation of washed human platelets with protease-activated receptor agonists caused translocation of Akt to the membrane rapidly, whereas phosphorylation occurred later. The translocation of Akt was abolished in the presence of a Gq-selective inhibitor or in Gq-deficient murine platelets, indicating that Akt translocation is regulated downstream of Gq pathways. Interestingly, phosphatidylinositol 3-kinase (PI3K) inhibitors or P2Y12 antagonist abolished Akt phosphorylation without affecting Akt translocation to the membrane, suggesting that Akt translocation occurs through a PI3K/PIP3/Gi-independent mechanism. An Akt scaffolding protein, p21-activated kinase (PAK), translocates to the membrane after stimulation with protease-activated receptor agonists in a Gq-dependent manner, with the kinetics of translocation similar to that of Akt. Coimmunoprecipitation studies showed constitutive association of PAK and Akt, suggesting a possible role of PAK in Akt translocation. These results show, for the first time, an important role of the Gq pathway in mediating Akt translocation to the membrane in a novel Gi/PI3K/PIP3-independent mechanism.

  7. Chromosomal translocations in human cells are generated by canonical nonhomologous end-joining.

    Science.gov (United States)

    Ghezraoui, Hind; Piganeau, Marion; Renouf, Benjamin; Renaud, Jean-Baptiste; Sallmyr, Annahita; Ruis, Brian; Oh, Sehyun; Tomkinson, Alan E; Hendrickson, Eric A; Giovannangeli, Carine; Jasin, Maria; Brunet, Erika

    2014-09-18

    Breakpoint junctions of the chromosomal translocations that occur in human cancers display hallmarks of nonhomologous end-joining (NHEJ). In mouse cells, translocations are suppressed by canonical NHEJ (c-NHEJ) components, which include DNA ligase IV (LIG4), and instead arise from alternative NHEJ (alt-NHEJ). Here we used designer nucleases (ZFNs, TALENs, and CRISPR/Cas9) to introduce DSBs on two chromosomes to study translocation joining mechanisms in human cells. Remarkably, translocations were altered in cells deficient for LIG4 or its interacting protein XRCC4. Translocation junctions had significantly longer deletions and more microhomology, indicative of alt-NHEJ. Thus, unlike mouse cells, translocations in human cells are generated by c-NHEJ. Human cancer translocations induced by paired Cas9 nicks also showed a dependence on c-NHEJ, despite having distinct joining characteristics. These results demonstrate an unexpected and striking species-specific difference for common genomic rearrangements associated with tumorigenesis.

  8. Fingerprints of Galactic Loop I on the Cosmic Microwave Background

    DEFF Research Database (Denmark)

    Liu, Hao; Mertsch, Philipp; Sarkar, Subir

    2014-01-01

    We investigate possible imprints of galactic foreground structures such as the "radio loops" in the derived maps of the cosmic microwave background. Surprisingly, there is evidence for these not only at radio frequencies through their synchrotron radiation, but also at microwave frequencies where...

  9. Fingerprints of Galactic Loop I on the Cosmic Microwave Background

    DEFF Research Database (Denmark)

    Liu, Hao; Mertsch, Philipp; Sarkar, Subir

    2014-01-01

    We investigate possible imprints of galactic foreground structures such as the "radio loops" in the derived maps of the cosmic microwave background. Surprisingly, there is evidence for these not only at radio frequencies through their synchrotron radiation, but also at microwave frequencies where...... due to primordial gravitational waves from inflation....

  10. Z > 6 Galaxy Signatures in the Infrared Background and the 21-cm background

    Science.gov (United States)

    Cooray, A.

    2006-08-01

    We will discuss the signatures of the high-redshift galaxy formation in the near-infrared background. Ionizing sources at high redshift generically imprint a distinctive Lyman-cutoff feature and a unique spatial anisotropy signature to the IRB, both of which may be detectable in a short rocket flight. We will discuss the Cosmic Infrared Background ExpeRiment (CIBER), a rocket-borne instrument to probe the absolute spectrum and spatial anisotropy of the extragalactic InfraRed Background (IRB) optimized for detection of the integrated spatial anisotropies in the IR background from high-redshift galaxies. We will also discuss the signatures of first galaxies in the low radio frequency 21-cm background from the neutral Hydrogen distribution at z > 6; When combined with arcminute-scale temperature anisotropy and the polarization of the cosmic microwave background, the 21-cm background will allow a determination of inhomogeneous distribution of Lyman-alpha photons from first galaxies. We will discuss these and other possibilities to understand the first galaxy population with IR, 21-cm, and CMB backgrounds.

  11. JEM-X background models

    DEFF Research Database (Denmark)

    Huovelin, J.; Maisala, S.; Schultz, J.

    2003-01-01

    Background and determination of its components for the JEM-X X-ray telescope on INTEGRAL are discussed. A part of the first background observations by JEM-X are analysed and results are compared to predictions. The observations are based on extensive imaging of background near the Crab Nebula...

  12. The influence of hydrogen peroxide and histamine on lung permeability and translocation of iridium nanoparticles in the isolated perfused rat lung

    Directory of Open Access Journals (Sweden)

    Takenaka Shinji

    2005-06-01

    Full Text Available Abstract Background Translocation of ultrafine particles (UFP into the blood that returns from the lungs to the heart has been forwarded as a mechanism for particle-induced cardiovascular effects. The objective of this study was to evaluate the role of the endothelial barrier in the translocation of inhaled UFP from the lung into circulation. Methods The isolated perfused rat lung (IPRL was used under negative pressure ventilation, and radioactive iridium particles (18 nm, CMD, 192Ir-UFP were inhaled during 60 minutes to achieve a lung burden of 100 – 200 μg. Particle inhalation was done under following treatments: i control perfusion, ii histamine (1 μM in perfusate, iii luminal histamine instillation (1 mM, and iv luminal instillation of H2O2. Particle translocation to the perfusate was assessed by the radioactivity of 192Ir isotope. Lung permeability by the use of Tc99m-labeled diethylene triamine pentaacetic acid (DTPA. In addition to light microscopic morphological evaluation of fixed lungs, alkaline phosphatase (AKP and angiotensin converting enzyme (ACE in perfusate were measured to assess epithelial and endothelial integrity. Results Particle distribution in the lung was homogenous and similar to in vivo conditions. No translocation of Ir particles at negative pressure inhalation was detected in control IPL, but lungs pretreated with histamine (1 μM in the perfusate or with luminal H2O2 (0.5 mM showed small amounts of radioactivity (2–3 % dose in the single pass perfusate starting at 60 min of perfusion. Although the kinetics of particle translocation were different from permeability for 99mTc-DTPA, the pretreatments (H2O2, vascular histamine caused similar changes in the translocation of particles and soluble mediator. Increased translocation through epithelium and endothelium with a lag time of one hour occurred in the absence of epithelial and endothelial damage. Conclusion Permeability of the lung barrier to UFP or

  13. Incipient Genome Differentiation in Gossypium. III. Comparison of Chromosomes of G. HIRSUTUM and Asiatic Diploids Using Heterozygous Translocations.

    Science.gov (United States)

    Menzel, M Y; Hasenkampf, C A; Stewart, J M

    1982-01-01

    Hybrids between upland cotton (G. hirsutum, genome constitution 2A(h)D(h)) and either A-genome or D-genome diploid species exhibit 26 paired and 13 unpaired chromosomes at metaphase I. The A(h) and D(h) genomes are therefore considered homoeologous with those of the respective diploids. Previous studies, nevertheless, revealed a low level of ("incipient") differentiation between D(h) and various diploid D genomes. The diploid A genomes have been regarded as more closely homologous to A(h) on the basis of low preferential pairing and autotetraploid segregation ratios in allohexaploids.-The present study addressed the following questions: Are the diploid A genomes differentiated from A(h) in meiotic homology? If so, is the differentiation manifested equally by all 13 chromosomes or is it localized in certain chromosomes?-Three diploid A-genome lines representing G. herbaceum and G. arboreum were hybridized by in ovulo culture of embryos (1) with a standard line of G. hirsutum, which differs from G. herbaceum by two and from G. arboreum by three naturally occurring reciprocal translocations involving chromosomes 1-5, and (2) with six lines homozygous for experimental translocations involving chromosomes 6, 7, 10, 11, 12 and 13. Chiasma frequencies in hybrids were compared with those in appropriate G. hirsutum controls. In every comparison overall chiasma frequencies were slightly lower in the hybrids. Therefore A(h) appears to be differentiated from the diploid A genomes. No localized differentiation was detected in chromosomes marked by experimental translocations. The differentiation may be localized mainly in chromosomes 4 and 5.

  14. Supergravity backgrounds and symmetry superalgebras

    CERN Document Server

    Ertem, Ümit

    2016-01-01

    We consider the bosonic sectors of supergravity theories in ten and eleven dimensions which correspond to the low energy limits of string theories and M-theory. The solutions of supergravity field equations are known as supergravity backgrounds and the number of preserved supersymmetries in those backgrounds are determined by Killing spinors. We provide some examples of supergravity backgrounds which preserve different fractions of supersymmetry. An important invariant for the characterization of supergravity backgrounds is their Killing superalgebras which are constructed out of Killing vectors and Killing spinors of the background. After constructing Killing superalgebras of some special supergravity backgrounds, we discuss about the possibilities of the extensions of these superalgebras to include the higher degree hidden symmetries of the background.

  15. Translocation of positively and negatively charged polystyrene nanoparticles in an in vitro placental model.

    Science.gov (United States)

    Kloet, Samantha K; Walczak, Agata P; Louisse, Jochem; van den Berg, Hans H J; Bouwmeester, Hans; Tromp, Peter; Fokkink, Remco G; Rietjens, Ivonne M C M

    2015-10-01

    To obtain insight in translocation of nanoparticles across the placental barrier, translocation was studied for one positively and two negatively charged polystyrene nanoparticles (PS-NPs) of similar size in an in vitro model. The model consisted of BeWo b30 cells, derived from a human choriocarcinoma grown on a transwell insert forming a cell layer that separates an apical from a basolateral compartment. PS-NPs were characterized with respect to size, surface charge, morphology and protein corona. Translocation of PS-NPs was not related to PS-NP charge. Two PS-NPs were translocated across the BeWo transwell model to a lower extent than amoxicillin, a model compound known to be translocated over the placental barrier to only a limited extent, whereas one PS-NP showed a slightly higher translocation. Studies on the effect of transporter inhibitors on the translocation of the PS-NPs indicated that their translocation was not mediated by known transporters and mainly dependent on passive diffusion. It is concluded that the BeWo b30 model can be used as an efficient method to get an initial qualitative impression about the capacity of NPs to translocate across the placental barrier and set priorities in further in vivo studies on translocation of NPs to the fetus.

  16. Sec61β, a subunit of the Sec61 protein translocation channel at the Endoplasmic Reticulum, is involved in the transport of Gurken to the plasma membrane.

    Directory of Open Access Journals (Sweden)

    Kelkar Anshuman

    2009-02-01

    Full Text Available Abstract Background Protein translocation across the membrane of the Endoplasmic Reticulum (ER is the first step in the biogenesis of secretory and membrane proteins. Proteins enter the ER by the Sec61 translocon, a proteinaceous channel composed of three subunits, α, β and γ. While it is known that Sec61α forms the actual channel, the function of the other two subunits remains to be characterized. Results In the present study we have investigated the function of Sec61β in Drosophila melanogaster. We describe its role in the plasma membrane traffic of Gurken, the ligand for the Epidermal Growth Factor (EGF receptor in the oocyte. Germline clones of the mutant allele of Sec61β show normal translocation of Gurken into the ER and transport to the Golgi complex, but further traffic to the plasma membrane is impeded. The defect in plasma membrane traffic due to absence of Sec61β is specific for Gurken and is not due to a general trafficking defect. Conclusion Based on our study we conclude that Sec61β, which is part of the ER protein translocation channel affects a post-ER step during Gurken trafficking to the plasma membrane. We propose an additional role of Sec61β beyond protein translocation into the ER.

  17. Renal Cell Carcinoma Associated with Xp11.2 Translocation/TFE3 Gene Fusion: A Rare Case Report with Review of the Literature

    Directory of Open Access Journals (Sweden)

    Puneet Ahluwalia

    2013-01-01

    Full Text Available Introduction. The recently recognized renal cell carcinomas associated with Xp11.2 translocations are rare tumors predominantly reported in children. Chromosome Xp11.2 translocation results in gene fusion related to transcription factor E3 (TFE3 that plays an important role in proliferation and survival. Case Report. Herein, we present two cases of a TFE3 translocation-associated RCC in young female adults, one detected incidentally and the other one presenting with gross hematuria. Tumor is characterized by immunohistochemistry and a literature review with optimal treatment regimen is presented. Discussion. Xp11.2 translocation RCCs in adult patients are associated with advanced stages, large tumors, and extracapsular disease and usually have an aggressive clinical course. Conclusion. In TFE3 RCC, the genetic background may not only contribute to tumorigenesis, but also determine the response to chemotherapy and targeted therapy. Therefore it is necessary to diagnose this tumor entity accurately. Because of the small number of TFE3 gene fusion-related renal tumors described in the literature, the exact biologic behavior and impact of current treatment modalities remain to be uncertain.

  18. Acute Ethanol Intake Induces NAD(P)H Oxidase Activation and Rhoa Translocation in Resistance Arteries

    Science.gov (United States)

    Simplicio, Janaina A.; Hipólito, Ulisses Vilela; do Vale, Gabriel Tavares; Callera, Glaucia Elena; Pereira, Camila André; Touyz, Rhian M; Tostes, Rita de Cássia; Tirapelli, Carlos R.

    2016-01-01

    Background The mechanism underlying the vascular dysfunction induced by ethanol is not totally understood. Identification of biochemical/molecular mechanisms that could explain such effects is warranted. Objective To investigate whether acute ethanol intake activates the vascular RhoA/Rho kinase pathway in resistance arteries and the role of NAD(P)H oxidase-derived reactive oxygen species (ROS) on such response. We also evaluated the requirement of p47phox translocation for ethanol-induced NAD(P)H oxidase activation. Methods Male Wistar rats were orally treated with ethanol (1g/kg, p.o. gavage) or water (control). Some rats were treated with vitamin C (250 mg/kg, p.o. gavage, 5 days) before administration of water or ethanol. The mesenteric arterial bed (MAB) was collected 30 min after ethanol administration. Results Vitamin C prevented ethanol-induced increase in superoxide anion (O2-) generation and lipoperoxidation in the MAB. Catalase and superoxide dismutase activities and the reduced glutathione, nitrate and hydrogen peroxide (H2O2) levels were not affected by ethanol. Vitamin C and 4-methylpyrazole prevented the increase on O2- generation induced by ethanol in cultured MAB vascular smooth muscle cells. Ethanol had no effect on phosphorylation levels of protein kinase B (Akt) and eNOS (Ser1177 or Thr495 residues) or MAB vascular reactivity. Vitamin C prevented ethanol-induced increase in the membrane: cytosol fraction ratio of p47phox and RhoA expression in the rat MAB. Conclusion Acute ethanol intake induces activation of the RhoA/Rho kinase pathway by a mechanism that involves ROS generation. In resistance arteries, ethanol activates NAD(P)H oxidase by inducing p47phox translocation by a redox-sensitive mechanism. PMID:27812679

  19. Stabilization of dicentric translocations through secondary rearrangements mediated by multiple mechanisms in S. cerevisiae.

    Directory of Open Access Journals (Sweden)

    Vincent Pennaneach

    Full Text Available BACKGROUND: The gross chromosomal rearrangements (GCRs observed in S. cerevisiae mutants with increased rates of accumulating GCRs include predicted dicentric GCRs such as translocations, chromosome fusions and isoduplications. These GCRs resemble the genome rearrangements found as mutations underlying inherited diseases as well as in the karyotypes of many cancers exhibiting ongoing genome instability METHODOLOGY/PRINCIPAL FINDINGS: The structures of predicted dicentric GCRs were analyzed using multiple strategies including array-comparative genomic hybridization, pulse field gel electrophoresis, PCR amplification of predicted breakpoints and sequencing. The dicentric GCRs were found to be unstable and to have undergone secondary rearrangements to produce stable monocentric GCRs. The types of secondary rearrangements observed included: non-homologous end joining (NHEJ-dependent intramolecular deletion of centromeres; chromosome breakage followed by NHEJ-mediated circularization or broken-end fusion to another chromosome telomere; and homologous recombination (HR-dependent non-reciprocal translocations apparently mediated by break-induced replication. A number of these GCRs appeared to have undergone multiple bridge-fusion-breakage cycles. We also observed examples of chromosomes with extensive ongoing end decay in mec1 tlc1 mutants, suggesting that Mec1 protects chromosome ends from degradation and contributes to telomere maintenance by HR. CONCLUSIONS/SIGNIFICANCE: HR between repeated sequences resulting in secondary rearrangements was the most prevalent pathway for resolution of dicentric GCRs regardless of the structure of the initial dicentric GCR, although at least three other resolution mechanisms were observed. The resolution of dicentric GCRs to stable rearranged chromosomes could in part account for the complex karyotypes seen in some cancers.

  20. Mitochondrial function in Antarctic nototheniids with ND6 translocation.

    Directory of Open Access Journals (Sweden)

    Felix C Mark

    Full Text Available Fish of the suborder Notothenioidei have successfully radiated into the Southern Ocean and today comprise the dominant fish sub-order in Antarctic waters in terms of biomass and species abundance. During evolution in the cold and stable Antarctic climate, the Antarctic lineage of notothenioids developed several unique physiological adaptations, which make them extremely vulnerable to the rapid warming of Antarctic waters currently observed. Only recently, a further phenomenon exclusive to notothenioid fish was reported: the translocation of the mitochondrial gene encoding the NADH Dehydrogenase subunit 6 (ND6, an indispensable part of complex I in the mitochondrial electron transport system.This study investigated the potential physiological consequences of ND6 translocation for the function and thermal sensitivity of the electron transport system in isolated liver mitochondria of the two nototheniid species Notothenia coriiceps and Notothenia rossii, with special attention to the contributions of complex I (NADH DH and complex II (Succinate DH to oxidative phosphorylation. Furthermore, enzymatic activities of NADH:Cytochrome c Oxidoreductase and Cytochrome C Oxidase were measured in membrane-enriched tissue extracts.During acute thermal challenge (0-15°C, capacities of mitochondrial respiration and enzymatic function in the liver could only be increased until 9°C. Mitochondrial complex I (NADH Dehydrogenase was fully functional but displayed a higher thermal sensitivity than the other complexes of the electron transport system, which may specifically result from its unique amino acid composition, revealing a lower degree of stability in notothenioids in general. We interpret the translocation of ND6 as functionally neutral but the change in amino acid sequence as adaptive and supportive of cold stenothermy in Antarctic nototheniids. From these findings, an enhanced sensitivity to ocean warming can be deduced for Antarctic notothenioid fish.

  1. Mitochondrial function in Antarctic nototheniids with ND6 translocation.

    Science.gov (United States)

    Mark, Felix C; Lucassen, Magnus; Strobel, Anneli; Barrera-Oro, Esteban; Koschnick, Nils; Zane, Lorenzo; Patarnello, Tomaso; Pörtner, Hans O; Papetti, Chiara

    2012-01-01

    Fish of the suborder Notothenioidei have successfully radiated into the Southern Ocean and today comprise the dominant fish sub-order in Antarctic waters in terms of biomass and species abundance. During evolution in the cold and stable Antarctic climate, the Antarctic lineage of notothenioids developed several unique physiological adaptations, which make them extremely vulnerable to the rapid warming of Antarctic waters currently observed. Only recently, a further phenomenon exclusive to notothenioid fish was reported: the translocation of the mitochondrial gene encoding the NADH Dehydrogenase subunit 6 (ND6), an indispensable part of complex I in the mitochondrial electron transport system.This study investigated the potential physiological consequences of ND6 translocation for the function and thermal sensitivity of the electron transport system in isolated liver mitochondria of the two nototheniid species Notothenia coriiceps and Notothenia rossii, with special attention to the contributions of complex I (NADH DH) and complex II (Succinate DH) to oxidative phosphorylation. Furthermore, enzymatic activities of NADH:Cytochrome c Oxidoreductase and Cytochrome C Oxidase were measured in membrane-enriched tissue extracts.During acute thermal challenge (0-15°C), capacities of mitochondrial respiration and enzymatic function in the liver could only be increased until 9°C. Mitochondrial complex I (NADH Dehydrogenase) was fully functional but displayed a higher thermal sensitivity than the other complexes of the electron transport system, which may specifically result from its unique amino acid composition, revealing a lower degree of stability in notothenioids in general. We interpret the translocation of ND6 as functionally neutral but the change in amino acid sequence as adaptive and supportive of cold stenothermy in Antarctic nototheniids. From these findings, an enhanced sensitivity to ocean warming can be deduced for Antarctic notothenioid fish.

  2. Effect of probiotics on enterocyte bacterial translocation in vitro.

    Science.gov (United States)

    Mattar, A F; Drongowski, R A; Coran, A G; Harmon, C M

    2001-05-01

    Enteral probiotics such as Lactobacillus casei GG (LGG) have been used in the treatment of a variety of intestinal disorders in infants and children, including diarrhea, malabsorption, and Clostridium difficile colitis. We have previously demonstrated that the probiotic bacterium LGG has an inhibitory effect on bacterial translocation (BT) in a neonatal rabbit model. However, this in-vivo model is limited for investigating the cellular and molecular mechanisms responsible for probiotic inhibition of BT. The purpose of this study was to determine the efficacy of LGG in reducing the rate of Escherichia coli C25 (E. coli C25) translocation using an in-vitro enterocyte cell-culture model. Human colonic carcinoma (Caco-2) enterocytes were seeded in porous filters in the apical chamber of a two-chamber cell-culture system and grown for 14 days to confluence. The monolayers were incubated at 37 degrees C with LGG for 180 min. Non-adherent LGG was washed away prior to a 120-min incubation period with 10(5) CFU E. coli C25. E. coli that had translocated across the enterocyte monolayer were quantified by growing basal-chamber media samples on gram-negative bacteria-specific MacConkey's agar. In order to determine monolayer integrity, transepithelial electrical resistance (TEER) was measured across Caco-2 cells treated with LGG and E. coli. Statistical analysis was by ANOVA with P probiotic bacterium LGG inhibits BT of E. coli C25 in a dose-dependent manner in an in-vitro cell-culture model. This model should be valuable in investigating the cellular and molecular mechanisms involved in the inhibition of pathological enteral bacteria by probiotic agents.

  3. Cytogenetic and molecular characteristics of 25 Chilean patients with a variant Ph translocation.

    Science.gov (United States)

    Legues, Maria E; Encina, Andrea; Valenzuela, Mercedes; Palma, Tamara; Undurraga, Maria S

    2011-07-01

    Chronic myeloid leukemia (CML) is characterized by the presence of the Philadelphia chromosome (Ph), which results from a balanced translocation between chromosomes 9 and 22, the t(9;22)(q34;q11.2). In 5-10% of the cases, variants of the Ph (vPh) are detected, involving various breakpoints in addition to 9q34 and 22q11.2. Deletions on the der(9) and der(22) can be detected in approximately 10-15% of CML patients. The frequency of a deletion of the der(9) in vPh CML is variable. Most studies have shown high frequencies (30-45%) in this subgroup. We report the cytogenetic evaluation of 25 vPh cases, which represents 6.8% of the CML cases diagnosed at one institution in 20 years. The breakpoints of the partners of the vPh in our patients agree with those reported previously, except for a novel 18q23. We found a low incidence of deletions of the der(9) (10%) and der(22) (5%) in these patients, contrasting with several reports in the literature. This finding may reflect the extensive spectrum of aberrations in vPh, and the possibility that a considerable group of these aberrations may not affect the genetic stability of 5'ABL1 and 3'BCR. Epidemiologic differences may also exist and could explain our results. These differences would require further investigation.

  4. Wilsonian flows and background fields

    CERN Document Server

    Litim, Daniel F; Litim, Daniel F.; Pawlowski, Jan M.

    2002-01-01

    We study exact renormalisation group flows for background field dependent regularisations. It is shown that proper-time flows are approximations to exact background field flows for a specific class of regulators. We clarify the role of the implicit scale dependence introduced by the background field. Its impact on the flow is evaluated numerically for scalar theories at criticality for different approximations and regularisations. Implications for gauge theories are discussed.

  5. Background subtraction theory and practice

    CERN Document Server

    Elgammal, Ahmed

    2014-01-01

    Background subtraction is a widely used concept for detection of moving objects in videos. In the last two decades there has been a lot of development in designing algorithms for background subtraction, as well as wide use of these algorithms in various important applications, such as visual surveillance, sports video analysis, motion capture, etc. Various statistical approaches have been proposed to model scene backgrounds. The concept of background subtraction also has been extended to detect objects from videos captured from moving cameras. This book reviews the concept and practice of back

  6. Genetic background of Fuchs' heterochromic cyclitis.

    Science.gov (United States)

    Saari, M; Vuorre, I; Tiilikainen, A; Algvere, P

    1978-10-01

    We studied the genetic background of 24 patients with Fuchs' heterochromic cyclitis (FHC). Each was given a careful eye examination which included family history and serological determination of HLA antigens. Two families each had 2 cases of FHC in the same family; in addition an ancestor in the second family possibly had FHC; in both families one healthy member had simple heterochromia. One patient with FHC had congenital uveal coloboma, one pigmentary retinal dystrophy, and four had cysts of the ciliary body. The frequencies of all HLA antigens in patients with FHC compared well with the frequencies in the controls. In a family in which HLA haplotypes could be derived, the patients with FHC showed different HLA haplotypes. We conclude that FHC has a hereditary basis but its immunological component is not genetically associated with the HLA system.

  7. Nonparametric Inference for the Cosmic Microwave Background

    CERN Document Server

    Genovese, C R; Nichol, R C; Arjunwadkar, M; Wasserman, L; Genovese, Christopher R.; Miller, Christopher J.; Nichol, Robert C.; Arjunwadkar, Mihir; Wasserman, Larry

    2004-01-01

    The Cosmic Microwave Background (CMB), which permeates the entire Universe, is the radiation left over from just 380,000 years after the Big Bang. On very large scales, the CMB radiation field is smooth and isotropic, but the existence of structure in the Universe - stars, galaxies, clusters of galaxies - suggests that the field should fluctuate on smaller scales. Recent observations, from the Cosmic Microwave Background Explorer to the Wilkinson Microwave Anisotropy Project, have strikingly confirmed this prediction. CMB fluctuations provide clues to the Universe's structure and composition shortly after the Big Bang that are critical for testing cosmological models. For example, CMB data can be used to determine what portion of the Universe is composed of ordinary matter versus the mysterious dark matter and dark energy. To this end, cosmologists usually summarize the fluctuations by the power spectrum, which gives the variance as a function of angular frequency. The spectrum's shape, and in particular the ...

  8. Driven polymer translocation in good and bad solvent: effects of hydrodynamics and tension propagation

    CERN Document Server

    Moisio, Jaakko E; Linna, Riku P

    2016-01-01

    We investigate the driven polymer translocation through a nanometer-scale pore in the presence and absence of hydrodynamics both in good and bad solvent. We measure tension of the polymer segment on the {\\it cis} side of the pore in the course of translocations simulated using stochastic rotation dynamics, also called multi-particle collision dynamics. We find that in the good solvent the tension propagates similarly whether hydrodynamics is included or not. Only the tensed segment is by a constant factor shorter in the presence of hydrodynamics. The shorter tensed segment and the hydrodynamic interactions contribute to a smaller friction for the translocating polymer when hydrodynamics is included, which shows as smaller waiting times and a smaller exponent in the scaling of the translocation time with the polymer length. Hydrodynamics speeds up translocation in the good solvent, whereas it has a minimal effect on polymer translocation in the bad solvent. Under bad-solvent conditions tension does not spread ...

  9. Use of chromosome translocations for measuring prior environment exposures in humans

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, J. D.

    1997-05-01

    Recent advances in cytogenetic methodology are beginning to have a major impact upon our ability to provide assessments of environmental exposure in humans. The advent of fluorescent-based techniques for `painting` whole chromosomes has made the analysis of chromosome translocations rapid, specific, sensitive and routine. Chromosome painting has been used to address a wide variety of scientific questions, resulting in an increased understanding of the biological consequences of adverse environmental exposure. This paper describes the use of chromosome translocations as a biological marker of exposure and effect in humans. The relevance of translocations is discussed, as are the advantages and disadvantages of painting compared to classical cytogenetic methods for translocation evaluation. The factors to consider in the use of translocations as a retrospective indicator of exposure are then described. Several theoretical parameters that are important to the use of translocations are provided, and the paper concludes with a vision for the future of cytogenetic methodology.

  10. Backgrounds and characteristics of arsonists

    NARCIS (Netherlands)

    Labree, W.; Nijman, H.L.I.; Marle, H.J.C. van; Rassin, E.

    2010-01-01

    The aim of this study was to gain more insight in the backgrounds and characteristics of arsonists. For this, the psychiatric, psychological, personal, and criminal backgrounds of all arsonists (n = 25), sentenced to forced treatment in the maximum security forensic hospital “De Kijvelanden”, were c

  11. Measurement of natural background neutron

    CERN Document Server

    Li Jain, Ping; Tang Jin Hua; Tang, E S; Xie Yan Fong

    1982-01-01

    A high sensitive neutron monitor is described. It has an approximate counting rate of 20 cpm for natural background neutrons. The pulse amplitude resolution, sensitivity and direction dependence of the monitor were determined. This monitor has been used for natural background measurement in Beijing area. The yearly average dose is given and compared with the results of KEK and CERN.

  12. Novel Bread Wheat Lines Enriched in Carotenoids Carrying Hordeum chilense Chromosome Arms in the ph1b Background

    Science.gov (United States)

    Rey, María-Dolores; Calderón, María-Carmen; Rodrigo, María Jesús; Zacarías, Lorenzo; Alós, Enriqueta; Prieto, Pilar

    2015-01-01

    The use of crop wild relative species to improve major crops performance is well established. Hordeum chilense has a high potential as a genetic donor to increase the carotenoid content of wheat. Crosses between the 7Hch H. chilense substitution lines in wheat and the wheat pairing homoeologous1b (ph1b) mutant allowed the development of wheat-H. chilense translocation lines for both 7Hchα and 7Hchβ chromosome arms in the wheat background. These translocation lines were characterized by in situ hybridization and using molecular markers. In addition, reverse phase chromatography (HPLC) analysis was carried out to evaluate the carotenoid content and both 7Hchα∙7AL and 7AS∙7Hchβ disomic translocation lines. The carotenoid content in 7Hchα∙7AL and 7AS∙7Hchβ disomic translocation lines was higher than the wheat-7Hch addition line and double amount of carotenoids than the wheat itself. A proteomic analysis confirmed that the presence of chromosome 7Hch introgressions in wheat scarcely altered the proteomic profile of the wheat flour. The Psy1 (Phytoene Synthase1) gene, which is the first committed step in the carotenoid biosynthetic pathway, was also cytogenetically mapped on the 7Hchα chromosome arm. These new wheat-H. chilense translocation lines can be used as a powerful tool in wheat breeding programs to enrich the diet in bioactive compounds. PMID:26241856

  13. Novel Bread Wheat Lines Enriched in Carotenoids Carrying Hordeum chilense Chromosome Arms in the ph1b Background.

    Directory of Open Access Journals (Sweden)

    María-Dolores Rey

    Full Text Available The use of crop wild relative species to improve major crops performance is well established. Hordeum chilense has a high potential as a genetic donor to increase the carotenoid content of wheat. Crosses between the 7Hch H. chilense substitution lines in wheat and the wheat pairing homoeologous1b (ph1b mutant allowed the development of wheat-H. chilense translocation lines for both 7Hchα and 7Hchβ chromosome arms in the wheat background. These translocation lines were characterized by in situ hybridization and using molecular markers. In addition, reverse phase chromatography (HPLC analysis was carried out to evaluate the carotenoid content and both 7Hchα∙7AL and 7AS∙7Hchβ disomic translocation lines. The carotenoid content in 7Hchα∙7AL and 7AS∙7Hchβ disomic translocation lines was higher than the wheat-7Hch addition line and double amount of carotenoids than the wheat itself. A proteomic analysis confirmed that the presence of chromosome 7Hch introgressions in wheat scarcely altered the proteomic profile of the wheat flour. The Psy1 (Phytoene Synthase1 gene, which is the first committed step in the carotenoid biosynthetic pathway, was also cytogenetically mapped on the 7Hchα chromosome arm. These new wheat-H. chilense translocation lines can be used as a powerful tool in wheat breeding programs to enrich the diet in bioactive compounds.

  14. Translocation of the neonicotinoid seed treatment clothianidin in maize

    Science.gov (United States)

    Krupke, Christian H.

    2017-01-01

    Neonicotinoid seed treatments, typically clothianidin or thiamethoxam, are routinely applied to >80% of maize (corn) seed grown in North America where they are marketed as a targeted pesticide delivery system. Despite this widespread use, the amount of compound translocated into plant tissue from the initial seed treatment to provide protection has not been reported. Our two year field study compared concentrations of clothianidin seed treatments in maize to that of maize without neonicotinoid seed treatments and found neonicotinoids present in root tissues up to 34 days post planting. Plant-bound clothianidin concentrations followed an exponential decay pattern with initially high values followed by a rapid decrease within the first ~20 days post planting. A maximum of 1.34% of the initial seed treatment was successfully recovered from plant tissues in both study years and a maximum of 0.26% was recovered from root tissue. Our findings show neonicotinoid seed treatments may provide protection from some early season secondary maize pests. However, the proportion of the neonicotinoid seed treatment clothianidin translocated into plant tissues throughout the growing season is low overall and this observation may provide a mechanism to explain reports of inconsistent efficacy of this pest management approach and increasing detections of environmental neonicotinoids. PMID:28282441

  15. Aspartic acid substitutions affect proton translocation by bacteriorhodopsin.

    Science.gov (United States)

    Mogi, T; Stern, L J; Marti, T; Chao, B H; Khorana, H G

    1988-01-01

    We have substituted each of the aspartic acid residues in bacteriorhodopsin to determine their possible role in proton translocation by this protein. The aspartic acid residues were replaced by asparagines; in addition, Asp-85, -96, -115, and -112 were changed to glutamic acid and Asp-212 was also replaced by alanine. The mutant bacteriorhodopsin genes were expressed in Escherichia coli and the proteins were purified. The mutant proteins all regenerated bacteriorhodopsin-like chromophores when treated with a detergent-phospholipid mixture and retinal. However, the rates of regeneration of the chromophores and their lambda max varied widely. No support was obtained for the external point charge model for the opsin shift. The Asp-85----Asn mutant showed not detectable proton pumping, the Asp-96----Asn and Asp-212----Glu mutants showed less than 10% and the Asp-115----Glu mutant showed approximately equal to 30% of the normal proton pumping. The implications of these findings for possible mechanisms of proton translocation by bacteriorhodopsin are discussed. PMID:3288985

  16. Clomazone dissipation, adsorption and translocation in four paddy topsoils.

    Science.gov (United States)

    Li, Lian-fang; Li, Guo-xue; Yang, Ren-bin; Guo, Zheng-yuan; Liao, Xiao-yong

    2004-01-01

    Laboratory experiments about the dissipation, adsorption and translocation in four paddy topsoils were conducted in this paper. From the results it can be concluded as follows: the dissipation rate of clomazone differed greatly in different paddy soil derived from different parent materials. The half-lives for clomazone degradation in paddy soils ranged from 5.7 to 22.0 d. The order of clomazone dissipation rate was reddish yellow paddy soil > alluvial sandy paddy soil > yellow clayey paddy soil > purple sandy paddy soil. Clomazone sorption quantity was significantly correlated with organic carbon (R2 = 0.62) and clay content(R2 = 0.67) in the tested paddy soils. Positive correlation was found between apparent Kd value and cation exchange content(CEC). The consequences for the adsorption of different soils were purple sandy paddy soil > yellow clayey paddy soil > reddish yellow paddy soil > alluvial sandy paddy soil. Under the simulated rainfall of 200 mm through four different unsaturated soil lysimeters over 24 h, clomazone was readily to be leached into lower surface soil and there was about 2.6%--4.2% of applied clomazone leached out of 20 cm cultivated soil layer. Translocation experiments showed that the order of clomazone leaching ability was: alluvial sandy paddy soil > reddish yellow paddy soil > yellow clayey paddy soil > purple sandy paddy soil. Simple regression results manifested that factors like CEC, organic carbon, clay, and adsorption rate constant had been negatively correlated with the percentage of clomazone loss from soil lysimeters.

  17. Reverse translocation of tRNA in the ribosome.

    Science.gov (United States)

    Shoji, Shinichiro; Walker, Sarah E; Fredrick, Kurt

    2006-12-28

    A widely held view is that directional movement of tRNA in the ribosome is determined by an intrinsic mechanism and driven thermodynamically by transpeptidation. Here, we show that, in certain ribosomal complexes, the pretranslocation (PRE) state is thermodynamically favored over the posttranslocation (POST) state. Spontaneous and efficient conversion from the POST to PRE state is observed when EF-G is depleted from ribosomes in the POST state or when tRNA is added to the E site of ribosomes containing P-site tRNA. In the latter assay, the rate of tRNA movement is increased by streptomycin and neomycin, decreased by tetracycline, and not affected by the acylation state of the tRNA. In one case, we provide evidence that complex conversion occurs by reverse translocation (i.e., direct movement of the tRNAs from the E and P sites to the P and A sites, respectively). These findings have important implications for the energetics of translocation.

  18. Muscle contraction increases carnitine uptake via translocation of OCTN2.

    Science.gov (United States)

    Furuichi, Yasuro; Sugiura, Tomoko; Kato, Yukio; Takakura, Hisashi; Hanai, Yoshiteru; Hashimoto, Takeshi; Masuda, Kazumi

    2012-02-24

    Since carnitine plays an important role in fat oxidation, influx of carnitine could be crucial for muscle metabolism. OCTN2 (SLC22A5), a sodium-dependent solute carrier, is assumed to transport carnitine into skeletal muscle cells. Acute regulation of OCTN2 activity in rat hindlimb muscles was investigated in response to electrically induced contractile activity. The tissue uptake clearance (CL(uptake)) of l-[(3)H]carnitine during muscle contraction was examined in vivo using integration plot analysis. The CL(uptake) of [(14)C]iodoantipyrine (IAP) was also determined as an index of tissue blood flow. To test the hypothesis that increased carnitine uptake involves the translocation of OCTN2, contraction-induced alteration in the subcellular localization of OCTN2 was examined. The CL(uptake) of l-[(3)H]carnitine in the contracting muscles increased 1.4-1.7-fold as compared to that in the contralateral resting muscles (pmuscle plasma membrane marker) showed an increase in OCTN2 signal in the plasma membrane after muscle contraction. Western blotting showed that the level of sarcolemmal OCTN2 was greater in contracting muscles than in resting muscles (pmuscle contraction facilitated carnitine uptake in skeletal muscles, possibly via the contraction-induced translocation of its specific transporter OCTN2 to the plasma membrane.

  19. Clinical Expression of an Inherited Unbalanced Translocation in Chromosome 6

    Directory of Open Access Journals (Sweden)

    Bani Bandana Ganguly

    2011-01-01

    Full Text Available Unbalanced chromosomal rearrangements are not common; however, they have a significant clinical expression. The parental balanced translocation produces unbalanced chromosome, which is transmitted to next generation through fertilization of gametes carrying the derivative chromosome. The carriers of balanced rearrangements mostly do not have recognizable phenotypic expression. We report a family comprising of healthy and non-consanguineous young parents and their preemie newborn severely affected with congenital anomalies and systemic disorders. Conventional Gbanding analysis of somatic chromosomes identified a balanced translocation, t(6;10(p23;q24, in mother and an unbalanced rearrangement, der(6t(6:10(p23;q24mat, in the child. The child has inherited a derivative chromosome 6 with partial deletion of 6(p23-pter and partial trisomy 10(q24-qter, which has resulted in fusion of genes of two different chromosomes. The prominent phenotypic features of del(6p, including high forehead, flat nasal bridge, agenesis of left ear, atrial septal defect (ASD, craniosynostosis, and growth retardation, are overlapping with specific Axenfeld-Reiger-, Larsen-, and Ritscher-Sinzel/3-C syndromes, however, lacking in ocular anomalies, skeletal laxity, or cerebellar malformation. Therefore, this paper rules out the isolated effect of del(6p23 or trisomy 10(q24 on distinct previously reported syndromes and proposes the combined effect of unbalanced chromosomal alteration.

  20. Insertional translocations: report of two new families and review of the literature.

    Science.gov (United States)

    Abuelo, D N; Barsel-Bowers, G; Richardson, A

    1988-10-01

    We describe two families with insertional translocations. In the first, a large family ascertained because of repeated pregnancy loss, the insertional translocation, ins(1;3)(q32;p13pter), was found to be segregating through three generations. In the second family, ascertained through a proposita with congenital malformations, multiple spontaneous abortions also occurred. The father had an insertional translocation, inv 4(p14,q21.1)ins(7,4)(q32;q21.1 q23). These cases illustrate that recurrent fetal wastage may be caused by insertional translocations and in fact may be the only clinical manifestation of this unusual type of chromosome rearrangement.

  1. Pore-polymer interaction reveals non-universality in forced polymer translocation

    CERN Document Server

    Lehtola, V V; Linna, R P

    2010-01-01

    We present a numerical study of forced polymer translocation by using two separate pore models. Both of them have been extensively used in previous forced translocation studies. We show that variations in the pore model affect the forced translocation characteristics significantly in the biologically relevant pore force, i.e. driving force, range. Details of the model are shown to change even the obtained scaling relations, which is a strong indication of strongly out-of-equilibrium dynamics in the computational studies which have not yet succeeded in addressing the characteristics of the forced translocation for biopolymers at realistic length scale.

  2. Can Characteristics of Reciprocal Translocations Predict the Chance of Transferable Embryos in PGD Cycles?

    Directory of Open Access Journals (Sweden)

    Elsbeth Dul

    2014-04-01

    Full Text Available Translocation carriers have an increased risk of miscarriage or the birth of a child with congenital anomalies. Preimplantation genetic diagnosis (PGD is performed in translocation carriers to select for balanced embryos and, thus, increase the chance of an ongoing pregnancy. However, a common experience is that reciprocal translocation carriers produce a high percentage of unbalanced embryos, which cannot be transferred. Therefore, the pregnancy rates in PGD in this patient group are low. In a cohort of 85 reciprocal translocation carriers undergoing PGD we have searched for cytogenetic characteristics of the translocations that can predict the percentage of balanced embryos. Using shape algorithms, the most likely segregation mode per translocation was determined. Shape algorithm, breakpoint location, and relative chromosome segment sizes proved not to be independent predictors of the percentage of balanced embryos. The ratio of the relative sizes of the translocated segments of both translocation chromosomes can give some insight into the chance of transferable embryos: Very asymmetrical translocations have a higher risk of unbalanced products (p = 0.048. Counseling of the couples on the pros and cons of all their reproductive options remains very important.

  3. Translocation of reindeer from South Georgia to the Falkland Islands

    Directory of Open Access Journals (Sweden)

    Cameron M. Bell

    2010-03-01

    Full Text Available This report describes the first translocation of reindeer Rangifer tarandus from South Georgia to the Falkland Islands, in the South Atlantic Ocean. Reindeer were introduced from Norway to the subantarctic island of South Georgia on three occasions in the early 1900s by Norwegian whalers, and today they exist as two discrete herds, numbering approximately 2600 individuals in total. Because of concerns over the impact on native vegetation, the long-term eradication of reindeer from South Georgia has recently been proposed. A translocation of reindeer to the Falkland Islands was undertaken in 2001 by the Falkland Island Government with two objectives: (1 to preserve the genetic resources of at least one of the South Georgia herds; and (2 to facilitate the diversification of the agricultural sector of the Falkland Islands by establishing a commercial reindeer herd. Techniques developed and used in North America for the successful relocation of large numbers of calves were adopted for the translocation. A total of 59 calves (26 females and 33 males were successfully translocated from South Georgia to the Falklands Islands in 2001, and subsequently produced their first offspring in 2003. Good husbandry practices and an understanding of biology and behaviour are essential for the successful translocation of reindeer.Flytting av rein fra Sør-Georgia til FalklandsøyeneAbstract in Norwegian / Sammendrag: Artikkelen beskriver den første overføring av rein Rangifer tarandus fra Sør-Georgia til Falklandsøyene i søratlanteren. Tamrein fra Norge ble flyttet til den subarktiske øya Sør-Georgia ved tre anledninger i perioden 1911 til 1925 i forbindelse med den norske hvalfangsten der. I dag består bestanden av rundt regnet 2600 dyr fordelt på to geografisk atskilte flokker. Av hensyn til den naturlige vegetasjonen på øya er det forslag om å på sikt utrydde reinbestanden på øya. Regjeringen på Falklandsøyene foretok en første overføring av

  4. Protein kinase A antagonist inhibits β-catenin nuclear translocation, c-Myc and COX-2 expression and tumor promotion in ApcMin/+ mice

    Directory of Open Access Journals (Sweden)

    Brudvik Kristoffer W

    2011-12-01

    Full Text Available Abstract Background The adenomatous polyposis coli (APC protein is part of the destruction complex controlling proteosomal degradation of β-catenin and limiting its nuclear translocation, which is thought to play a gate-keeping role in colorectal cancer. The destruction complex is inhibited by Wnt-Frz and prostaglandin E2 (PGE2 - PI-3 kinase pathways. Recent reports show that PGE2-induced phosphorylation of β-catenin by protein kinase A (PKA increases nuclear translocation indicating two mechanisms of action of PGE2 on β-catenin homeostasis. Findings Treatment of ApcMin/+ mice that spontaneously develop intestinal adenomas with a PKA antagonist (Rp-8-Br-cAMPS selectively targeting only the latter pathway reduced tumor load, but not the number of adenomas. Immunohistochemical characterization of intestines from treated and control animals revealed that expression of β-catenin, β-catenin nuclear translocation and expression of the β-catenin target genes c-Myc and COX-2 were significantly down-regulated upon Rp-8-Br-cAMPS treatment. Parallel experiments in a human colon cancer cell line (HCT116 revealed that Rp-8-Br-cAMPS blocked PGE2-induced β-catenin phosphorylation and c-Myc upregulation. Conclusion Based on our findings we suggest that PGE2 act through PKA to promote β-catenin nuclear translocation and tumor development in ApcMin/+ mice in vivo, indicating that the direct regulatory effect of PKA on β-catenin nuclear translocation is operative in intestinal cancer.

  5. Cosmic backgrounds of relic gravitons and their absolute normalization

    CERN Document Server

    Giovannini, Massimo

    2014-01-01

    Provided the consistency relations are not violated, the recent Bicep2 observations pin down the absolute normalization, the spectral slope and the maximal frequency of the cosmic graviton background produced during inflation. The properly normalized spectra are hereby computed from the lowest frequencies (of the order of the present Hubble rate) up to the highest frequency range in the GHz region. Deviations from the conventional paradigm cannot be excluded and are examined by allowing for different physical possibilities including, in particular, a running of the tensor spectral index, an explicit breaking of the consistency relations and a spike in the high-frequency tail of the spectrum coming either from a post-inflationary phase dominated by a stiff fluid of from the contribution of waterfall fields in a hybrid inflationary context. The direct determinations of the tensor to scalar ratio at low frequencies, if confirmed by the forthcoming observations, will also affect and constrain the high-frequencies...

  6. Berkeley Low Background Counting Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Sensitive low background assay detectors and sample analysis are available for non-destructive direct gamma-ray assay of samples. Neutron activation analysis is also...

  7. Backgrounds in AFP Detector Estimation

    CERN Document Server

    Huang, Yicong

    2016-01-01

    The ATLAS Forward Proton (AFP) detectors aim to measure protons that are scattered in the ATLAS interaction point under very small angles ($90-160 \\mu rad$). The diffractive protons detected by the AFP may be accompanied by beam halo. This report presents an estimation of the beam halo backgrounds in the AFP using low pile-up data, and position distributions of the backgrounds in the AFP.

  8. The molecular structure of the Na(+)-translocating F1F0-ATPase of Acetobacterium woodii, as revealed by electron microscopy, resembles that of H(+)-translocating ATPases.

    Science.gov (United States)

    Reidlinger, J; Mayer, F; Müller, V

    1994-12-12

    The Na(+)-translocating F1F0-ATPase of Acetobacterium woodii was examined by electron microscopy. After reconstitution into proteoliposomes, knobs typical for the F1 domain were visible on the outside of the membrane. The F1-part of the isolated enzyme showed a hexagonal symmetry suggesting an alpha 3 beta 3 structure, and the F1F0 complex had molecular dimensions very similar to those of H(+)-translocating ATPases of E. coli, chloroplasts, and mitochondria.

  9. Microwave Frequency Polarizers

    Science.gov (United States)

    Ha, Vien The; Mirel, Paul; Kogut, Alan J.

    2013-01-01

    This article describes the fabrication and analysis of microwave frequency polarizing grids. The grids are designed to measure polarization from the cosmic microwave background. It is effective in the range of 500 to 1500 micron wavelength. It is cryogenic compatible and highly robust to high load impacts. Each grid is fabricated using an array of different assembly processes which vary in the types of tension mechanisms to the shape and size of the grids. We provide a comprehensive study on the analysis of the grids' wire heights, diameters, and spacing.

  10. Translocator protein-mediated pharmacology of cholesterol transport and steroidogenesis.

    Science.gov (United States)

    Papadopoulos, Vassilios; Aghazadeh, Yasaman; Fan, Jinjiang; Campioli, Enrico; Zirkin, Barry; Midzak, Andrew

    2015-06-15

    Steroidogenesis begins with cholesterol transfer into mitochondria through the transduceosome, a complex composed of cytosolic proteins that include steroidogenesis acute regulatory protein (STAR), 14-3-3 adaptor proteins, and the outer mitochondrial membrane proteins Translocator Protein (TSPO) and Voltage-Dependent Anion Channel (VDAC). TSPO is a drug- and cholesterol-binding protein found at particularly high levels in steroid synthesizing cells. Its aberrant expression has been linked to cancer, neurodegeneration, neuropsychiatric disorders and primary hypogonadism. Brain steroids serve as local regulators of neural development and excitability. Reduced levels of these steroids have been linked to depression, anxiety and neurodegeneration. Reduced serum testosterone is common among subfertile young men and aging men, and is associated with depression, metabolic syndrome and reduced sexual function. Although testosterone-replacement therapy is available, there are undesired side-effects. TSPO drug ligands have been proposed as therapeutic agents to regulate steroid levels in the brain and testis.

  11. Markers of immunity and bacterial translocation in cirrhosis

    DEFF Research Database (Denmark)

    Mortensen, Christian

    2015-01-01

    complications. The optimal surrogate marker of BT in patients with cirrhosis, however, is a matter of controversy. In the first study, we investigated the relationship between markers of inflammation, haemodynamics and prognosis in 45 patients and 12 controls. We found high-sensitive C-reactive protein......, in 38 patients with ascites, we found no association between bDNA and immunity, in contrast to some previous findings. In the final paper, exploring one possible translocation route, we hypothesized a difference in bDNA levels between the blood from the veins draining the gut on one hand and the liver...... on the other. Collecting samples during the insertion of a shunt between the two vessels in 28 patients, our finding did not suggest marked differences in bDNA, but conversely to expectations, suggested marked hepatic production of two markers of inflammation. The main results of the present thesis support...

  12. Microhomology directs diverse DNA break repair pathways and chromosomal translocations.

    Directory of Open Access Journals (Sweden)

    Diana D Villarreal

    Full Text Available Chromosomal structural change triggers carcinogenesis and the formation of other genetic diseases. The breakpoint junctions of these rearrangements often contain small overlapping sequences called "microhomology," yet the genetic pathway(s responsible have yet to be defined. We report a simple genetic system to detect microhomology-mediated repair (MHMR events after a DNA double-strand break (DSB in budding yeast cells. MHMR using >15 bp operates as a single-strand annealing variant, requiring the non-essential DNA polymerase subunit Pol32. MHMR is inhibited by sequence mismatches, but independent of extensive DNA synthesis like break-induced replication. However, MHMR using less than 14 bp is genetically distinct from that using longer microhomology and far less efficient for the repair of distant DSBs. MHMR catalyzes chromosomal translocation almost as efficiently as intra-chromosomal repair. The results suggest that the intrinsic annealing propensity between microhomology sequences efficiently leads to chromosomal rearrangements.

  13. Retro-translocation of mitochondrial intermembrane space proteins

    Science.gov (United States)

    Bragoszewski, Piotr; Wasilewski, Michal; Sakowska, Paulina; Gornicka, Agnieszka; Böttinger, Lena; Qiu, Jian; Wiedemann, Nils; Chacinska, Agnieszka

    2015-01-01

    The content of mitochondrial proteome is maintained through two highly dynamic processes, the influx of newly synthesized proteins from the cytosol and the protein degradation. Mitochondrial proteins are targeted to the intermembrane space by the mitochondrial intermembrane space assembly pathway that couples their import and oxidative folding. The folding trap was proposed to be a driving mechanism for the mitochondrial accumulation of these proteins. Whether the reverse movement of unfolded proteins to the cytosol occurs across the intact outer membrane is unknown. We found that reduced, conformationally destabilized proteins are released from mitochondria in a size-limited manner. We identified the general import pore protein Tom40 as an escape gate. We propose that the mitochondrial proteome is not only regulated by the import and degradation of proteins but also by their retro-translocation to the external cytosolic location. Thus, protein release is a mechanism that contributes to the mitochondrial proteome surveillance. PMID:26056291

  14. Uniparental disomy in Robertsonian translocations: strategies for uniparental disomy testing.

    Science.gov (United States)

    Yip, Moh-Ying

    2014-04-01

    Robertsonian translocations (ROBs) are whole arm rearrangements involving the acrocentric chromosomes 13-15 and 21-22 and carriers are at increased risk for aneuploidy and thus uniparental disomy (UPD). Chromosomes 14 and 15 are imprinted with expression of genes dependent on the parental origin of the chromosome. Correction of a trisomic or monosomic conceptus for chromosomes 14 or 15 would lead to one of the established UPD 14mat/pat or UPD 15 (Prader-Willi/Angelman) syndromes (PWS/AS). In view of this, prenatal UPD testing should be considered for balanced carriers of a ROB, fetuses with a familial or de novo balanced ROB that contains chromosome 14 or 15 or with a normal karyotype when a parent is a carrier of a balanced ROB with a 14 or 15. Individuals with congenital anomalies and an abnormal phenotype and carry a ROB involving the two imprinted chromosomes should also be UPD tested.

  15. Mechanism of long-range proton translocation along biological membranes.

    Science.gov (United States)

    Medvedev, Emile S; Stuchebrukhov, Alexei A

    2013-02-14

    Recent experiments suggest that protons can travel along biological membranes up to tens of micrometers, but the mechanism of transport is unknown. To explain such a long-range proton translocation we describe a model that takes into account the coupled bulk diffusion that accompanies the migration of protons on the surface. We show that protons diffusing at or near the surface before equilibrating with the bulk desorb and re-adsorb at the surface thousands of times, giving rise to a power-law desorption kinetics. As a result, the decay of the surface protons occurs very slowly, allowing for establishing local gradient and local exchange, as was envisioned in the early local models of biological energy transduction.

  16. Dermatoifbrosarcoma protuberans:from translocation to targeted therapy

    Institute of Scientific and Technical Information of China (English)

    Jonathan Noujaim; Khin Thway; Cyril Fisher; Robin L. Jones

    2015-01-01

    Dermatoifbrosarcoma protuberans (DFSP), the most common dermal sarcoma, is a low-grade, slow growing ifbroblastic malignant neoplasm that most frequently affects middle aged adults and is characterized by a high local recurrence rate and a low propensity for metastasis. Wide surgical resection or Mohs micrographic surgery (MMS) are the preferred approaches for localized disease, while radiation therapy is warranted for inoperable disease or for cases with positive margins where re-excision is not possible. DFSP is generally regarded as refractory to conventional chemotherapy. Treatment options for systemic disease were limited until the discovery of a unique translocation, t(17;22)(q22;q13) (COL1A1;PDGFB) found in a majority of cases. In recent years, imatinib, a PDGFβR, ABL and KIT inhibitor, has revolutionized systemic therapy in DFSP. In this review, we summarize the epidemiological, clinical, histological and genetic characteristics of DFSP and update the readers on its current management.

  17. Clomazone dissipation,adsorption and translocation in four paddy topsoils

    Institute of Scientific and Technical Information of China (English)

    LI Lian-fang; LI Guo-xue; YANG Ren-bin; GUO Zheng-yuan; LIAO Xiao-yong

    2004-01-01

    Laboratory experiments about the dissipation, adsorption and translocation in four paddy topsoils were conducted in this paper. From the results it can be concluded as follows: the dissipation rate of clomazone differed greatly in different paddy soil derived from different parent materials. The half-lives for clomazone degradation in paddy soils ranged from 5.7 to 22.0 d. The order of clomazone dissipation rate was reddish yellow paddy soil >alluvial sandy paddy soil > yellow clayey paddy soil > purple sandy paddy soil. Clomazone sorption quantity was significantly correlated with organic carbon ( R2 = 0.62) and clay content ( R2 = 0.67) in the tested paddy soils.Positive correlation was found between apparent Kd value and cation exchange content(CEC). The consequences for the adsorption of different soils were purple sandy paddy soil > yellow clayey paddy soil > reddish yellow paddy soil > alluvial sandy paddy soil. Under the simulated rainfall of 200 mm through four different unsaturated soil lysimeters over 24 h, clomazone was readily to be leached into lower surface soil and there was about 2.6%-4.2%of applied clomazone leached out of 20 cm cultivated soil layer. Translocation experiments showed that the order of clomazone leaching ability was: alluvial sandy paddy soil > reddish yellow paddy soil > yellow clayey paddy soil >purple sandy paddy soil. Simple regression results manifested that factors like CEC, organic carbon, clay, and adsorption rate constant had been negatively correlated with the percentage of clomazone loss from soil lysimeters.

  18. Biosynthesis and translocation of unsulfated acyltrehaloses in Mycobacterium tuberculosis.

    Science.gov (United States)

    Belardinelli, Juan Manuel; Larrouy-Maumus, Gérald; Jones, Victoria; Sorio de Carvalho, Luiz Pedro; McNeil, Michael R; Jackson, Mary

    2014-10-03

    A number of species-specific polymethyl-branched fatty acid-containing trehalose esters populate the outer membrane of Mycobacterium tuberculosis. Among them, 2,3-diacyltrehaloses (DAT) and penta-acyltrehaloses (PAT) not only play a structural role in the cell envelope but also contribute to the ability of M. tuberculosis to multiply and persist in the infected host, promoting the intracellular survival of the bacterium and modulating host immune responses. The nature of the machinery, topology, and sequential order of the reactions leading to the biosynthesis, assembly, and export of these complex glycolipids to the cell surface are the object of the present study. Our genetic and biochemical evidence corroborates a model wherein the biosynthesis and translocation of DAT and PAT to the periplasmic space are coupled and topologically split across the plasma membrane. The formation of DAT occurs on the cytosolic face of the plasma membrane through the action of PapA3, FadD21, and Pks3/4; that of PAT occurs on the periplasmic face via transesterification reactions between DAT substrates catalyzed by the acyltransferase Chp2 (Rv1184c). The integral membrane transporter MmpL10 is essential for DAT to reach the cell surface, and its presence in the membrane is required for Chp2 to be active. Disruption of mmpL10 or chp2 leads to an important build-up of DAT inside the cells and to the formation of a novel form of unsulfated acyltrehalose esterified with polymethyl-branched fatty acids normally found in sulfolipids that is translocated to the cell surface.

  19. Competition between Sec- and TAT-dependent protein translocation in Escherichia coli

    DEFF Research Database (Denmark)

    Cristóbal, S.; de Gier, J.-W.; Nielsen, Henrik

    1999-01-01

    Recently, a new protein translocation pathway, the twin-arginine translocation (TAT) pathway, has been identified in both bacteria and chloroplasts. To study the possible competition between the TAT- and the well-characterized Sec translocon-dependent pathways in Escherichia coli, we have fused...

  20. Translocation of positively and negatively charged polystyrene nanoparticles in an in vitro placental model

    NARCIS (Netherlands)

    Kloet, S.K.; Walczak, A.P.; Louisse, J.; Berg, H.H.J. van den; Bouwmeester, H.; Tromp, P.; Fokkink, R.G.; Rietjens, I.M.C.M.

    2015-01-01

    To obtain insight in translocation of nanoparticles across the placental barrier, translocation was studied for one positively and two negatively charged polystyrene nanoparticles (PS-NPs) of similar size in an in vitro model. The model consisted of BeWo b30 cells, derived from a human choriocarcino

  1. ESX-1-mediated translocation to the cytosol controls virulence of mycobacteria

    KAUST Repository

    Houben, Diane

    2012-05-08

    Mycobacterium species, including Mycobacterium tuberculosis and Mycobacterium leprae, are among the most potent human bacterial pathogens. The discovery of cytosolic mycobacteria challenged the paradigm that these pathogens exclusively localize within the phagosome of host cells. As yet the biological relevance of mycobacterial translocation to the cytosol remained unclear. In this current study we used electron microscopy techniques to establish a clear link between translocation and mycobacterial virulence. Pathogenic, patient-derived mycobacteria species were found to translocate to the cytosol, while non-pathogenic species did not. We were further able to link cytosolic translocation with pathogenicity by introducing the ESX-1 (type VII) secretion system into the non-virulent, exclusively phagolysosomal Mycobacterium bovis BCG. Furthermore, we show that translocation is dependent on the C-terminus of the early-secreted antigen ESAT-6. The C-terminal truncation of ESAT-6 was shown to result in attenuation in mice, again linking translocation to virulence. Together, these data demonstrate the molecular mechanism facilitating translocation of mycobacteria. The ability to translocate from the phagolysosome to the cytosol is with this study proven to be biologically significant as it determines mycobacterial virulence. © 2012 Blackwell Publishing Ltd.

  2. Development and Identification of Triticum aestivum L.-Thinopyrum bessarabicum L(o)ve Chromosome Translocations

    Institute of Scientific and Technical Information of China (English)

    ZHUANG Li-fang; QI Zeng-jun; CHEN Pei-du; FENG Yi-gao; LIU Da-jun

    2004-01-01

    With ass7istance of chromosome C-banding and genomic in situ hybridization(GISH)combined with meiotic analysis,five germplasms with homozygous wheat-Th. Bessarabicum chromosome translocations were developed and identified among BC1F5 progenies of the cross between T. Aestivum cv. Chinese Spring and Chinese Spring-Th. Bessarabicum amphiploid. These lines included Tj01 and Tj02(2n=44)containing a pair of wheat-Th. Bessarabicum translocation chromosomes besides a pair of added Th. Bessarabicum chromosomes,Tj03(2n=44)with a pair of added interspecific translocation chromosomes,Tj04(2n=44)containing a pair of interspecific translocation chromosomes besides an added pair of Th. Bessarabicum chromosome arms and Tj05(2n=46)containing a pair of interspecific translocation chromosomes besides two pairs of added intact alien chromosomes. The breakpoints of all the translocations were found to be not around centromere. Meanwhile,all the lines showed normal plant growth,development and fertility,while the translocation chromosomes transmitted regularly. The obtained translocations might be of use for transferring elite genes from Th. Bessarabicum into wheat.

  3. Molecular and classical cytogenetic analyses demonstrate an apomorphic reciprocal chromosomal translocation in Gorilla gorilla

    OpenAIRE

    Stanyon, Roscoe; Wienberg, Johannes; Romagno, D.; Bigoni, F.; Jauch, Anna; Cremer, Thomas

    1992-01-01

    The existence of an apomorphic reciprocal chromosomal translocation in the gorilla lineage has been asserted or denied by various cytogeneticists. We employed a new molecular cytogenetic strategy (chromosomal in situ suppression hybridization) combined with high-resolution banding, replication sequence analysis, and fluorochrome staining to demonstrate that a reciprocal translocation between ancestral chromosomes homologous to human chromosome 5 and 17 has indeed occurred.

  4. Proton transfer is rate-limiting for translocation of precursor proteins by the Escherichia coli translocase

    NARCIS (Netherlands)

    Driessen, Arnold J.M.; Wickner, William

    1991-01-01

    The protonmotive force stimulates translocation in vivo, in crude in vitro reactions, and in a purified, reconstituted reaction. Translocation activity is a function of the pH at the inner face of the membrane. Both the transmembrane pH gradient and the transmembrane electrical potential stimulate t

  5. X monosomy and balanced Robertsonian translocation in a girl with Turner Syndrome

    Directory of Open Access Journals (Sweden)

    Aline Lourenço da Silva

    2006-01-01

    Full Text Available We describe a case of X monosomy associated with a maternally inherited t(13;14 Robertsonian translocation in a girl with Turner syndrome. The girl's X chromosome was demonstrated to be maternally inherited, ruling out the hypothesis that the translocation exerted an interchromosomal effect on the origin of the monosomy. Chromosomes 13 and 14 showed biparental inheritance.

  6. Genome-wide translocation sequencing reveals mechanisms of chromosome breaks and rearrangements in B cells.

    Science.gov (United States)

    Chiarle, Roberto; Zhang, Yu; Frock, Richard L; Lewis, Susanna M; Molinie, Benoit; Ho, Yu-Jui; Myers, Darienne R; Choi, Vivian W; Compagno, Mara; Malkin, Daniel J; Neuberg, Donna; Monti, Stefano; Giallourakis, Cosmas C; Gostissa, Monica; Alt, Frederick W

    2011-09-30

    Whereas chromosomal translocations are common pathogenetic events in cancer, mechanisms that promote them are poorly understood. To elucidate translocation mechanisms in mammalian cells, we developed high-throughput, genome-wide translocation sequencing (HTGTS). We employed HTGTS to identify tens of thousands of independent translocation junctions involving fixed I-SceI meganuclease-generated DNA double-strand breaks (DSBs) within the c-myc oncogene or IgH locus of B lymphocytes induced for activation-induced cytidine deaminase (AID)-dependent IgH class switching. DSBs translocated widely across the genome but were preferentially targeted to transcribed chromosomal regions. Additionally, numerous AID-dependent and AID-independent hot spots were targeted, with the latter comprising mainly cryptic I-SceI targets. Comparison of translocation junctions with genome-wide nuclear run-ons revealed a marked association between transcription start sites and translocation targeting. The majority of translocation junctions were formed via end-joining with short microhomologies. Our findings have implications for diverse fields, including gene therapy and cancer genomics.

  7. Electron microscopic visualization of asymmetric precursor translocation intermediates:SecA functions as a dimer

    Institute of Scientific and Technical Information of China (English)

    TAI; Phang; C

    2010-01-01

    SecA,the ATPase of Sec translocase,mediates the post-translational translocation of preprotein through the protein-conduct-ing channel SecYEG in the bacterial inner membrane.Here we report the structures of Escherichia coli Sec intermediates during preprotein translocation as visualized by electron microscopy to probe the oligomeric states of SecA during this process.We found that the translocase holoenzyme is symmetrically assembled by SecA and SecYEG on proteoliposomes,whereas the translocation intermediate 31 (I31) becomes asymmetric because of the presence of preprotein.Moreover,SecA is a dimer in these two translocation complexes.This work also shows surface topological changes in the components of translocation intermediates by immunogold labeling.The channel entry for preprotein translocation was found at the center of the I31 structures.Our results indicate that the presence of preprotein introduces asymmetry into translocation intermediates,while SecA remains dimeric during the translocation process.

  8. Balanced reciprocal translocation at amniocentesis: cytogenetic detection and implications for genetic counseling.

    Science.gov (United States)

    Zhang, H G; Zhang, X Y; Zhang, H Y; Tian, T; Xu, S B; Liu, R Z

    2016-08-19

    Balanced translocation is a common structural chromosomal rearrangement in humans. Carriers can be phenotypically normal but have an increased risk of pregnancy loss, fetal death, and the transmission of chromosomal abnormalities to their offspring. Existing prenatal screening technologies and diagnostic procedures fail to detect balanced translocation, so genetic counseling for carriers remains a challenge. Here, we report the characteristics of chromosomal reciprocal translocation in 3807 amniocentesis cases. Of the 16 detected cases of fetal reciprocal translocation, 8 cases (50%) showed positive biochemical marker screening; 3 cases (18.75%) were the parental carriers of a chromosomal abnormality; 2 (12.5%) were of advanced maternal age, 2 (12.5%) had a previous history of children with genetic disorders, and 1 case (6.25%) was associated with positive soft markers in obstetric ultrasound. Chromosomes 5 and 19 were the most commonly involved chromosomes in balanced translocations. Of the 13 cases with fetal balanced translocations, 8 (61.5%) were inherited from a paternal chromosome, 3 (23.1%) from a maternal chromosome, and 2 (15.4%) cases were de novo. The incidence of balanced translocation at amniocentesis was 0.42%. Male carriers of reciprocal chromosome translocation appear to have a higher chance of becoming a parent of a child born by normal childbirth than female carriers.

  9. Translocation of closed polymers through a nanopore under an applied external field

    Science.gov (United States)

    Jiang, Shao-Chuan; Zhang, Lin-Xi; Xia, A.-Gen; Chen, Hong-Ping; Cheng, Jun

    2010-01-01

    The dynamic behaviours of the translocations of closed circular polymers and closed knotted polymers through a nanopore, under the driving of an applied field, are studied by three-dimensional Langevin dynamics simulations. The power-law scaling of the translocation time τ with the chain length N and the distribution of translocation time are investigated separately. For closed circular polymers, a crossover scaling of translocation time with chain length is found to be τ simeq Nα, with the exponent α varying from α = 0.71 for relatively short chains to α = 1.29 for longer chains under driving force F = 5. The scaling behaviour for longer chains is in good agreement with experimental results, in which the exponent α = 1.27 for the translocation of double-strand DNA. The distribution of translocation time D(τ) is close to a Gaussian function for duration time τ τp. For closed knotted polymers, the scaling exponent α is 1.27 for small field force (F = 5) and 1.38 for large field force (F = 10). The distribution of translocation time D(τ) remarkably features two peaks appearing in the case of large driving force. The interesting result of multiple peaks can conduce to the understanding of the influence of the number of strands of polymers in the pore at the same time on translocation dynamic process and scaling property.

  10. Stochastic Background Search Correlating ALLEGRO with LIGO Engineering Data

    CERN Document Server

    Whelan, J T; Heng, I S; McHugh, M P; Lazzarini, A; Whelan, John T; Daw, Edward; Heng, Ik Siong; Hugh, Martin P Mc; Lazzarini, Albert

    2003-01-01

    We describe the role of correlation measurements between the LIGO interferometer in Livingston, LA, and the ALLEGRO resonant bar detector in Baton Rouge, LA, in searches for a stochastic background of gravitational waves. Such measurements provide a valuable complement to correlations between interferometers at the two LIGO sites, since they are sensitive in a different, higher, frequency band. Additionally, the variable orientation of the ALLEGRO detector provides a means to distinguish gravitational wave correlations from correlated environmental noise. We describe the analysis underway to set a limit on the strength of a stochastic background at frequencies near 900 Hz using ALLEGRO data and data from LIGO's E7 Engineering Run.

  11. Hydrodynamic correlations in the translocation of biopolymer through a nanopore: theory and multiscale simulations

    CERN Document Server

    Fyta, Maria; Succi, Sauro; Kaxiras, Efthimios

    2008-01-01

    We investigate the process of biopolymer translocation through a narrow pore using a multiscale approach which explicitly accounts for the hydrodynamic interactions of the molecule with the surrounding solvent. The simulations confirm that the coupling of the correlated molecular motion to hydrodynamics results in significant acceleration of the translocation process. Based on these results, we construct a phenomenological model which incorporates the statistical and dynamical features of the translocation process and predicts a power law dependence of the translocation time on the polymer length with an exponent $\\alpha$ $\\approx 1.2$. The actual value of the exponent from the simulations is $\\alpha = 1.28 \\pm 0.01$, which is in excellent agreement with experimental measurements of DNA translocation through a nanopore, and is not sensitive to the choice of parameters in the simulation. The mechanism behind the emergence of such a robust exponent is related to the interplay between the longitudinal and transv...

  12. Numerical simulation of conformational variability in biopolymer translocation through wide nanopores

    CERN Document Server

    Fyta, Maria; Bernaschi, Massimo; Kaxiras, Efthimios; Succi, Sauro

    2009-01-01

    Numerical results on the translocation of long biopolymers through mid-sized and wide pores are presented. The simulations are based on a novel methodology which couples molecular motion to a mesoscopic fluid solvent. Thousands of events of long polymers (up to 8000 monomers) are monitored as they pass through nanopores. Comparison between the different pore sizes shows that wide pores can host a larger number of multiple biopolymer segments, as compared to smaller pores. The simulations provide clear evidence of folding quantization in the translocation process as the biopolymers undertake multi-folded configurations, characterized by a well-defined integer number of folds. Accordingly, the translocation time is no longer represented by a single-exponent power law dependence on the length, as it is the case for single-file translocation through narrow pores. The folding quantization increases with the biopolymer length, while the rate of translocated beads at each time step is linearly correlated to the numb...

  13. Background Independent String Field Theory

    CERN Document Server

    Bars, Itzhak

    2014-01-01

    We develop a new background independent Moyal star formalism in bosonic open string field theory. The new star product is formulated in a half-phase-space, and because phase space is independent of any background fields, the interactions are background independent. In this basis there is a large amount of symmetry, including a supersymmetry OSp(d|2) that acts on matter and ghost degrees of freedom, and simplifies computations. The BRST operator that defines the quadratic kinetic term of string field theory may be regarded as the solution of the equation of motion A*A=0 of a purely cubic background independent string field theory. We find an infinite number of non-perturbative solutions to this equation, and are able to associate them to the BRST operator of conformal field theories on the worldsheet. Thus, the background emerges from a spontaneous-type breaking of a purely cubic highly symmetric theory. The form of the BRST field breaks the symmetry in a tractable way such that the symmetry continues to be us...

  14. The Cosmic Infrared Background Experiment

    CERN Document Server

    Bock, J; Cooray, A R; Kawada, M; Keating, B; Lange, A; Lee, D H; Matsumoto, T; Matsuura, S; Pak, S; Renbarger, T; Sullivan, I; Tsumura, K; Wada, T; Watabe, T; Bock, James; Battle, John; Cooray, Asantha; Kawada, Mitsunobu; Keating, Brian; Lange, Andrew; Lee, Dae-Hea; Matsumoto, Toshio; Matsuura, Shuji; Pak, Soojong; Renbarger, Tom; Sullivan, Ian; Tsumura, Kohji; Wada, Takehiko; Watabe, Toyoki

    2006-01-01

    We are developing a rocket-borne instrument (the Cosmic Infrared Background ExpeRiment, or CIBER) to search for signatures of primordial galaxy formation in the cosmic near-infrared extra-galactic background. CIBER consists of a wide-field two-color camera, a low-resolution absolute spectrometer, and a high-resolution narrow-band imaging spectrometer. The cameras will search for spatial fluctuations in the background on angular scales from 7 arcseconds to 2 degrees over a range of angular scales poorly covered by previous experiments. CIBER will determine if the fluctuations reported by the IRTS arise from first-light galaxies or have a local origin. In a short rocket flight CIBER has sensitivity to probe fluctuations 100 times fainter than IRTS/DIRBE. By jointly observing regions of the sky studied by Spitzer and ASTRO-F, CIBER will build a multi-color view of the near-infrared background, accurately assessing the contribution of local (z = 1-3) galaxies to the observed background fluctuations, allowing a de...

  15. Cellular distribution of alkaloids and their translocation via phloem and xylem: the importance of compartment pH.

    Science.gov (United States)

    Nowak, M; Selmar, D

    2016-11-01

    The physico-chemical background of alkaloid allocation within plants is outlined and discussed exemplarily for pyrrolizidine alkaloids (PAs) and nicotine. The trigger for this discourse is the finding that, for example, PAs, which are taken up from the soil, are translocated in the xylem, whereas - when genuinely present in plants - they are allocated as N-oxides via phloem. Special emphasis is put on the impact of different pH values in certain compartments, as this entails significant changes in the relative lipophilic character of alkaloids: tertiary alkaloids diffuse readily through biomembranes, while the corresponding protonated alkaloids are retained in acidic compartments, i.e. vacuoles or xylem. Therefore, this phenomenon, well known as the 'ion trap mechanism', is also relevant for long-distance transport of alkaloids. Any efficient allocation of typical tertiary alkaloids within the phloem can thus be excluded. In contrast, due to their strongly increased hydrophilic properties, alkaloid-N-oxides or quarternary alkaloids cannot diffuse through biomembranes and, consequently, would be retained in the acidic xylem during translocation. The major aim of this paper is to sharpen the mind for the chemical peculiarities of alkaloids and to consider them adequately in forthcoming investigations on allocation of alkaloids.

  16. KDM6B Elicits Cell Apoptosis by Promoting Nuclear Translocation of FOXO1 in Non-Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Jun Ma

    2015-08-01

    Full Text Available Background/Aims: Non-small cell lung carcinoma (NSCLC is the most common type of lung cancer and the cause of most cancer-related deaths. The molecular mechanisms that are involved in NSCLC development are currently not well understood. Accumulating evidence shows that histone demethylases play important roles in the regulation of pathological developmental processes in many diseases, including various types of cancers. Methods: Mitochondrial membrane potential assays, migration and invasion assays, caspase-3 and caspase-9 activity assays and western blot analysis were used in this research. Results: We found that overexpression of KDM6B, a demethylase that acts on histone H3 at lysine 27 (H3K27, inhibited cell growth by initiating mitochondria-dependent apoptosis and by attenuating the invasion-metastasis cascade in NSCLC cells. Moreover, our results showed that KDM6B directly interacted with FOXO1 and that overexpression of KDM6B promoted nuclear accumulation of FOXO1. The effects of KDM6B on cell apoptosis and metastasis were weakened by knockdown of FOXO1 expression. On the contrary, knocking down expression of KDM6B inhibited cell apoptosis and promoted cell growth by mitigating the nuclear translocation of FOXO1 in NSCLC cells. Conclusions: These findings suggest that KDM6B may act in a pro-apoptotic role in NSCLC by causing the nuclear translocation of FOXO1.

  17. Neutron background estimates in GESA

    Directory of Open Access Journals (Sweden)

    Fernandes A.C.

    2014-01-01

    Full Text Available The SIMPLE project looks for nuclear recoil events generated by rare dark matter scattering interactions. Nuclear recoils are also produced by more prevalent cosmogenic neutron interactions. While the rock overburden shields against (μ,n neutrons to below 10−8 cm−2 s−1, it itself contributes via radio-impurities. Additional shielding of these is similar, both suppressing and contributing neutrons. We report on the Monte Carlo (MCNP estimation of the on-detector neutron backgrounds for the SIMPLE experiment located in the GESA facility of the Laboratoire Souterrain à Bas Bruit, and its use in defining additional shielding for measurements which have led to a reduction in the extrinsic neutron background to ∼ 5 × 10−3 evts/kgd. The calculated event rate induced by the neutron background is ∼ 0,3 evts/kgd, with a dominant contribution from the detector container.

  18. Background simulations and shielding calculations

    Science.gov (United States)

    Kudryavtsev, Vitaly A.

    2011-04-01

    Key improvements in the sensitivity of the underground particle astrophysics experiments can only be achieved if the radiation causing background events in detectors is well understood and proper measures are taken to suppress it. The background radiation arising from radioactivity and cosmic-ray muons is discussed here together with the methods of its suppression. Different shielding designs are considered to attenuate gamma-rays and neutrons coming from radioactivity in rock and lab walls. Purity of materials used in detector construction is analysed and the background event rates due to the presence of radioactive isotopes in detector components are discussed. Event rates in detectors caused by muon-induced neutrons with and without active veto systems are presented leading to the requirements for the depth of an underground laboratory and the efficiency of the veto system.

  19. Prophylactic treatment with growth hormone improves intestinal barrier function and alleviates bacterial translocation in stressed rats

    Institute of Scientific and Technical Information of China (English)

    丁连安; 黎介寿; 李幼生; 刘放南; 谭力

    2004-01-01

    Background Damage to the gut barrier often occurs during critical illnesses. In such cases, it is very important to alleviate impairment of the intestinal barrier and protect intestinal barrier function. This study investigated the protective effect of growth hormone on intestinal barrier function in rats under stress.Methods This study consisted of prospective, randomized, and controlled animal experiments. Twenty-five Sprague-Dawley rats served as total parenteral nutrition (TPN) models and were divided into three groups: TPN group, sepsis (Sep) group, and growth hormone (GH) group. Another 8 rats served as normal controls. Each group received different stress stimuli. Rats were fed for 7 days, and samples were taken for examination 24 hours after garaging with dual saccharides. Results The architecture of the small intestinal mucosa in the Sep group showed the most severe damage among all groups. Nitric oxide levels in blood plasma and immunoglobulin A levels in the intestinal mucosa of the GH group were significantly lower than in the Sep group (P<0.02). There were no significant changes in CD3 counts and in the CD4/CD8 ratio between the four groups. Dual sugar tests and bacteriological examinations revealed that intestinal permeability and rate of bacterial translocation in the GH group were lower than in the Sep group (P<0.01, respectively).Conclusion Prophylactic treatment with growth hormone can alleviate damage to intestinal barrier function caused by trauma and endotoxemia in rats under stress.

  20. Children of ethnic minority backgrounds

    DEFF Research Database (Denmark)

    Johansen, Stine Liv

    2010-01-01

    media products and toys just as they will have knowledge of different media texts, play genres, rhymes etc. This has consequences for their ability to access social settings, for instance in play. New research in this field will focus on how children themselves make sense of this balancing of cultures......Children of ethnic minority background balance their everyday life between a cultural background rooted in their ethnic origin and a daily life in day care, schools and with peers that is founded in a majority culture. This means, among other things, that they often will have access to different...

  1. Generative electronic background music system

    Energy Technology Data Exchange (ETDEWEB)

    Mazurowski, Lukasz [Faculty of Computer Science, West Pomeranian University of Technology in Szczecin, Zolnierska Street 49, Szczecin, PL (Poland)

    2015-03-10

    In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions.

  2. Exotic branes and nongeometric backgrounds.

    Science.gov (United States)

    de Boer, Jan; Shigemori, Masaki

    2010-06-25

    When string or M theory is compactified to lower dimensions, the U-duality symmetry predicts so-called exotic branes whose higher-dimensional origin cannot be explained by the standard string or M-theory branes. We argue that exotic branes can be understood in higher dimensions as nongeometric backgrounds or U folds, and that they are important for the physics of systems which originally contain no exotic charges, since the supertube effect generically produces such exotic charges. We discuss the implications of exotic backgrounds for black hole microstate (non-)geometries.

  3. Teaching about Natural Background Radiation

    Science.gov (United States)

    Al-Azmi, Darwish; Karunakara, N.; Mustapha, Amidu O.

    2013-01-01

    Ambient gamma dose rates in air were measured at different locations (indoors and outdoors) to demonstrate the ubiquitous nature of natural background radiation in the environment and to show that levels vary from one location to another, depending on the underlying geology. The effect of a lead shield on a gamma radiation field was also…

  4. Low Background Micromegas in CAST

    CERN Document Server

    Garza, J G; Aznar, F.; Calvet, D.; Castel, J.F.; Christensen, F.E.; Dafni, T.; Davenport, M.; Decker, T.; Ferrer-Ribas, E.; Galán, J.; García, J.A.; Giomataris, I.; Hill, R.M.; Iguaz, F.J.; Irastorza, I.G.; Jakobsen, A.C.; Jourde, D.; Mirallas, H.; Ortega, I.; Papaevangelou, T.; Pivovaroff, M.J.; Ruz, J.; Tomás, A.; Vafeiadis, T.; Vogel, J.K.

    2015-01-01

    Solar axions could be converted into x-rays inside the strong magnetic field of an axion helioscope, triggering the detection of this elusive particle. Low background x-ray detectors are an essential component for the sensitivity of these searches. We report on the latest developments of the Micromegas detectors for the CERN Axion Solar Telescope (CAST), including technological pathfinder activities for the future International Axion Observatory (IAXO). The use of low background techniques and the application of discrimination algorithms based on the high granularity of the readout have led to background levels below 10$^{-6}$ counts/keV/cm$^2$/s, more than a factor 100 lower than the first generation of Micromegas detectors. The best levels achieved at the Canfranc Underground Laboratory (LSC) are as low as 10$^{-7}$ counts/keV/cm$^2$/s, showing good prospects for the application of this technology in IAXO. The current background model, based on underground and surface measurements, is presented, as well as ...

  5. Low Background Micromegas in CAST

    DEFF Research Database (Denmark)

    Garza, J G; Aune, S.; Aznar, F.

    2014-01-01

    Solar axions could be converted into x-rays inside the strong magnetic field of an axion helioscope, triggering the detection of this elusive particle. Low background x-ray detectors are an essential component for the sensitivity of these searches. We report on the latest developments of the Micr...

  6. Educational Choice. A Background Paper.

    Science.gov (United States)

    Quality Education for Minorities Network, Washington, DC.

    This paper addresses school choice, one proposal to address parental involvement concerns, focusing on historical background, definitions, rationale for advocating choice, implementation strategies, and implications for minorities and low-income families. In the past, transfer payment programs such as tuition tax credits and vouchers were…

  7. Cosmic backgrounds of relic gravitons and their absolute normalization

    Science.gov (United States)

    Giovannini, Massimo

    2014-11-01

    Provided the consistency relations are not violated, the recent BICEP2 observations pin down the absolute normalization, the spectral slope and the maximal frequency of the cosmic graviton background produced during inflation. The properly normalized spectra are hereby computed from the lowest frequencies (of the order of the present Hubble rate) up to the highest frequency range in the GHz region. Deviations from the conventional paradigm cannot be excluded and are examined by allowing for different physical possibilities including, in particular, a running of the tensor spectral index, an explicit breaking of the consistency relations and a spike in the high-frequency tail of the spectrum coming either from a post-inflationary phase dominated by a stiff fluid or from the contribution of waterfall fields in a hybrid inflationary context. The direct determinations of the tensor to scalar ratio at low frequencies, if confirmed by the forthcoming observations, will also affect and constrain the high-frequency uncertainties. The limits on the cosmic graviton backgrounds coming from wide-band interferometers (such as LIGO/Virgo, LISA and BBO/DECIGO) together with a more accurate scrutiny of the tensor B-mode polarization at low frequencies will set direct bounds on the post-inflationary evolution and on other unconventional completions of the standard lore.

  8. The Cosmic Infrared Background Experiment

    Science.gov (United States)

    Bock, James; Battle, J.; Cooray, A.; Hristov, V.; Kawada, M.; Keating, B.; Lee, D.; Matsumoto, T.; Matsuura, S.; Nam, U.; Renbarger, T.; Sullivan, I.; Tsumura, K.; Wada, T.; Zemcov, M.

    2009-01-01

    We are developing the Cosmic Infrared Background ExpeRiment (CIBER) to search for signatures of first-light galaxy emission in the extragalactic background. The first generation of stars produce characteristic signatures in the near-infrared extragalactic background, including a redshifted Ly-cutoff feature and a characteristic fluctuation power spectrum, that may be detectable with a specialized instrument. CIBER consists of two wide-field cameras to measure the fluctuation power spectrum, and a low-resolution and a narrow-band spectrometer to measure the absolute background. The cameras will search for fluctuations on angular scales from 7 arcseconds to 2 degrees, where the first-light galaxy spatial power spectrum peaks. The cameras have the necessary combination of sensitivity, wide field of view, spatial resolution, and multiple bands to make a definitive measurement. CIBER will determine if the fluctuations reported by Spitzer arise from first-light galaxies. The cameras observe in a single wide field of view, eliminating systematic errors associated with mosaicing. Two bands are chosen to maximize the first-light signal contrast, at 1.6 um near the expected spectral maximum, and at 1.0 um; the combination is a powerful discriminant against fluctuations arising from local sources. We will observe regions of the sky surveyed by Spitzer and Akari. The low-resolution spectrometer will search for the redshifted Lyman cutoff feature in the 0.7 - 1.8 um spectral region. The narrow-band spectrometer will measure the absolute Zodiacal brightness using the scattered 854.2 nm Ca II Fraunhofer line. The spectrometers will test if reports of a diffuse extragalactic background in the 1 - 2 um band continues into the optical, or is caused by an under estimation of the Zodiacal foreground. We report performance of the assembled and tested instrument as we prepare for a first sounding rocket flight in early 2009. CIBER is funded by the NASA/APRA sub-orbital program.

  9. Physics of the cosmic microwave background anisotropy

    CERN Document Server

    Bucher, Martin

    2015-01-01

    Observations of the cosmic microwave background (CMB), especially of its frequency spectrum and its anisotropies, both in temperature and in polarization, have played a key role in the development of modern cosmology and our understanding of the very early universe. We review the underlying physics of the CMB and how the primordial temperature and polarization anisotropies were imprinted. Possibilities for distinguishing competing cosmological models are emphasized. The current status of CMB experiments and experimental techniques with an emphasis toward future observations, particularly in polarization, is reviewed. The physics of foreground emissions, especially of polarized dust, is discussed in detail, since this area is likely to become crucial for measurements of the B modes of the CMB polarization at ever greater sensitivity.

  10. Muscle contraction increases carnitine uptake via translocation of OCTN2

    Energy Technology Data Exchange (ETDEWEB)

    Furuichi, Yasuro [Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa (Japan); Sugiura, Tomoko; Kato, Yukio [Faculty of Pharmacy, Kanazawa University, Kanazawa (Japan); Takakura, Hisashi [Faculty of Human Sciences, Kanazawa University, Kanazawa (Japan); Hanai, Yoshiteru [Nagoya Institute of Technology, Nagoya (Japan); Hashimoto, Takeshi [Ritsumeikan University, Kusatsu (Japan); Masuda, Kazumi, E-mail: masuda@ed.kanazawa-u.ac.jp [Faculty of Human Sciences, Kanazawa University, Kanazawa (Japan)

    2012-02-24

    Highlights: Black-Right-Pointing-Pointer Muscle contraction augmented carnitine uptake into rat hindlimb muscles. Black-Right-Pointing-Pointer An increase in carnitine uptake was due to an intrinsic clearance, not blood flow. Black-Right-Pointing-Pointer Histochemical analysis showed sarcolemmal OCTN2 was emphasized after contraction. Black-Right-Pointing-Pointer OCTN2 protein in sarcolemmal fraction was increased in contracting muscles. -- Abstract: Since carnitine plays an important role in fat oxidation, influx of carnitine could be crucial for muscle metabolism. OCTN2 (SLC22A5), a sodium-dependent solute carrier, is assumed to transport carnitine into skeletal muscle cells. Acute regulation of OCTN2 activity in rat hindlimb muscles was investigated in response to electrically induced contractile activity. The tissue uptake clearance (CL{sub uptake}) of L-[{sup 3}H]carnitine during muscle contraction was examined in vivo using integration plot analysis. The CL{sub uptake} of [{sup 14}C]iodoantipyrine (IAP) was also determined as an index of tissue blood flow. To test the hypothesis that increased carnitine uptake involves the translocation of OCTN2, contraction-induced alteration in the subcellular localization of OCTN2 was examined. The CL{sub uptake} of L-[{sup 3}H]carnitine in the contracting muscles increased 1.4-1.7-fold as compared to that in the contralateral resting muscles (p < 0.05). The CL{sub uptake} of [{sup 14}C]IAP was much higher than that of L-[{sup 3}H]carnitine, but no association between the increase in carnitine uptake and blood flow was obtained. Co-immunostaining of OCTN2 and dystrophin (a muscle plasma membrane marker) showed an increase in OCTN2 signal in the plasma membrane after muscle contraction. Western blotting showed that the level of sarcolemmal OCTN2 was greater in contracting muscles than in resting muscles (p < 0.05). The present study showed that muscle contraction facilitated carnitine uptake in skeletal muscles, possibly

  11. Uptake, translocation, and toxicity of gold nanorods in maize

    Science.gov (United States)

    Moradi Shahmansouri, Nastaran

    Nanomaterials are widely used in many different products, such as electronics, cosmetics, industrial goods, biomedical uses, and other material applications. The heavy emission of nanomaterials into the environment has motived increasing concern regarding the effects on ecosystems, food chains, and, human health. Plants can tolerate a certain amount of natural nanomaterials, but large amounts of ENMs released from a variety of industries could be toxic to plants and possibly threaten the ecosystem. Employing phytoremediation as a contamination treatment method may show promise. However a pre-requisite to successful treatment is a better understanding of the behavior and effects of nanomaterials within plant systems. This study is designed to investigate the uptake, translocation, bioavailability, and toxicity of gold nanorods in maize plants. Maize is an important food and feed crop that can be used to understand the potential hazardous effects of nanoparticle uptake and distribution in the food chain. The findings could be an important contribution to the fields of phytoremediation, agri-nanotechnology, and nanoparticle toxicity on plants. In the first experiment, hydroponically grown maize seedlings were exposed to similar doses of commercial non-coated gold nanorods in three sizes, 10x34 nm, 20x75 nm, and 40x96 nm. The three nanorod species were suspended in solutions at concentrations of 350 mg/l, 5.8 mg/l, and 14 mg/l, respectively. Maize plants were exposed to all three solutions resulting in considerably lower transpiration and wet biomass than control plants. Likewise, dry biomass was reduced, but the effect is less pronounced than that of transpiration and wet biomass. The reduced transpiration and water content, which eventually proved fatal to exposed plants, were most likely a result of toxic effect of gold nanorod, which appeared to physically hinder the root system. TEM images proved that maize plants can uptake gold particles and accumulate them in

  12. Meiotic pairing and gene expression disturbance in germ cells from an infertile boar with a balanced reciprocal autosome-autosome translocation.

    Science.gov (United States)

    Barasc, Harmonie; Congras, Annabelle; Mary, Nicolas; Trouilh, Lidwine; Marquet, Valentine; Ferchaud, Stéphane; Raymond-Letron, Isabelle; Calgaro, Anne; Loustau-Dudez, Anne-Marie; Mouney-Bonnet, Nathalie; Acloque, Hervé; Ducos, Alain; Pinton, Alain

    2016-12-01

    Individuals carrying balanced constitutional reciprocal translocations generally have a normal phenotype, but often present reproductive disorders. The aim of our research was to analyze the meiotic process in an oligoasthenoteratospermic boar carrying an asymmetric reciprocal translocation involving chromosomes 1 and 14. Different multivalent structures (quadrivalent and trivalent plus univalent) were identified during chromosome pairing analysis. Some of these multivalents were characterized by the presence of unpaired autosomal segments with histone γH2AX accumulation sometimes associated with the XY body. Gene expression in spermatocytes was studied by RNA-DNA-FISH and microarray-based testis transcriptome analysis. Our results revealed a decrease in gene expression for chromosomes 1 and 14 and an up-regulated expression of X-chromosome genes for the translocated boar compared with normal individuals. We hypothesized that the observed meiotic arrest and reproductive failure in this boar might be due to silencing of crucial autosomal genes (MSUC) and disturbance of meiotic sex chromosome inactivation (MSCI). Further analysis revealed abnormal meiotic recombination (frequency and distribution) and the production of a high rate of unbalanced spermatozoa.

  13. Extensive nonhomologous meiotic synapsis between normal chromosome axes of an rcp(3;6)(p14;q21) translocation in a hairless Mexican boar.

    Science.gov (United States)

    Villagómez, D A F; Ayala-Valdovinos, M A; Galindo-García, J; Sánchez-Chipres, D R; Mora-Galindo, J; Taylor-Preciado, J J

    2008-01-01

    Due to its low fertility, expressed as small litter size, a Mexican hairless boar was subjected to cytogenetic investigation. Analysis of G-banded mitotic chromosomes revealed a reciprocal chromosome translocation, rcp(3;6) (p14;q21). Synaptonemal complex analysis showed a regular pairing behavior of the translocation chromosome axes, always resulting in a quadrivalent configuration. However, due to extensive nonhomologous pairing between the axes of nonderivative chromosomes 3 and 6, the quadrivalent mostly had an asymmetrical cross-shaped morphology. The nonhomologous pairing occurred not only at mid and late pachytene, but also at the earliest stage of pachytene. It seems that early pachytene heterosynapsis is a common phenomenon in the pairing behavior of pig reciprocal translocations. Therefore, heterosynapsis may reduce apoptosis of germ cells due to partial absence of homologous synapsis during the pairing phase of meiosis. The frequency of spermatocytes showing quadrivalent configurations with unpaired axial segments apparently did not affect germ cell progression in the boar, since fairly normal testicular histology was noticed.

  14. Quantitative Analysis of the Nanopore Translocation Dynamics of Simple Structured Polynucleotides

    Science.gov (United States)

    Schink, Severin; Renner, Stephan; Alim, Karen; Arnaut, Vera; Simmel, Friedrich C.; Gerland, Ulrich

    2012-01-01

    Nanopore translocation experiments are increasingly applied to probe the secondary structures of RNA and DNA molecules. Here, we report two vital steps toward establishing nanopore translocation as a tool for the systematic and quantitative analysis of polynucleotide folding: 1), Using α-hemolysin pores and a diverse set of different DNA hairpins, we demonstrate that backward nanopore force spectroscopy is particularly well suited for quantitative analysis. In contrast to forward translocation from the vestibule side of the pore, backward translocation times do not appear to be significantly affected by pore-DNA interactions. 2), We develop and verify experimentally a versatile mesoscopic theoretical framework for the quantitative analysis of translocation experiments with structured polynucleotides. The underlying model is based on sequence-dependent free energy landscapes constructed using the known thermodynamic parameters for polynucleotide basepairing. This approach limits the adjustable parameters to a small set of sequence-independent parameters. After parameter calibration, the theoretical model predicts the translocation dynamics of new sequences. These predictions can be leveraged to generate a baseline expectation even for more complicated structures where the assumptions underlying the one-dimensional free energy landscape may no longer be satisfied. Taken together, backward translocation through α-hemolysin pores combined with mesoscopic theoretical modeling is a promising approach for label-free single-molecule analysis of DNA and RNA folding. PMID:22225801

  15. TLR4 facilitates translocation of bacteria across renal collecting duct cells.

    Science.gov (United States)

    Chassin, Cécilia; Vimont, Sophie; Cluzeaud, Françoise; Bens, Marcelle; Goujon, Jean-Michel; Fernandez, Béatrice; Hertig, Alexandre; Rondeau, Eric; Arlet, Guillaume; Hornef, Mathias W; Vandewalle, Alain

    2008-12-01

    Uropathogenic Escherichia coli (UPEC) are the most frequent causes of urinary tract infections and pyelonephritis. Renal medullary collecting duct (MCD) cells are the intrarenal site to which UPEC strains prefer to adhere and initiate an inflammatory response, but the ability of UPEC strains to translocate across impermeant MCD cells has not been demonstrated definitively. Here, several UPEC strains adhered to the apical surface and translocated across confluent murine inner MCD cells grown on filters. UPEC strains expressing cytolytic and vacuolating cytotoxins disrupted the integrity of cell layers, whereas noncytolytic UPEC strains passed through the cell layers without altering tight junctions. Apical-to-basal transcellular translocation was dramatically reduced after extinction of Toll-like receptor 4 (TLR4) and the lipid raft marker caveolin-1 by small interfering RNA. Furthermore, disruption of lipid raft integrity by filipin III and methyl-beta-cyclodextrin significantly reduced both the transcellular translocation of UPEC across murine inner MCD cell layers and the stimulation of proinflammatory mediators. Bacterial translocation was also significantly reduced in primary cultures of TLR4-deficient mouse MCD cells compared with MCD cells from wild-type mice. Benzyl alcohol, an anesthetic that enhances membrane fluidity, favored the recruitment of caveolin-1 in lipid rafts and increased the translocation of UPEC across cultured TLR4-deficient MCD cells. These findings demonstrate that the transcellular translocation of UPEC strains across impermeant layers of MCD cells may occur through lipid rafts via a TLR4-facilitated process.

  16. Domain Organization in Clostridium botulinum Neurotoxin Type E is Unique: Its Implication in Faster Translocation

    Energy Technology Data Exchange (ETDEWEB)

    Kumaran, D.; Eswaramoorthy, S; Furey, W; Navaza, J; Sax, M; Swaminathan, S

    2009-01-01

    Clostridium botulinum produces seven antigenically distinct neurotoxins [C. botulinum neurotoxins (BoNTs) A-G] sharing a significant sequence homology. Based on sequence and functional similarity, it was believed that their three-dimensional structures will also be similar. Indeed, the crystal structures of BoNTs A and B exhibit similar fold and domain association where the translocation domain is flanked on either side by binding and catalytic domains. Here, we report the crystal structure of BoNT E holotoxin and show that the domain association is different and unique, although the individual domains are similar to those of BoNTs A and B. In BoNT E, both the binding domain and the catalytic domain are on the same side of the translocation domain, and all three have mutual interfaces. This unique association may have an effect on the rate of translocation, with the molecule strategically positioned in the vesicle for quick entry into cytosol. Botulism, the disease caused by BoNT E, sets in faster than any other serotype because of its speedy internalization and translocation, and the present structure offers a credible explanation. We propose that the translocation domain in other BoNTs follows a two-step process to attain translocation-competent conformation as in BoNT E. We also suggest that this translocation-competent conformation in BoNT E is a probable reason for its faster toxic rate compared to BoNT A. However, this needs further experimental elucidation.

  17. Background Subtraction Based on Three-Dimensional Discrete Wavelet Transform.

    Science.gov (United States)

    Han, Guang; Wang, Jinkuan; Cai, Xi

    2016-03-30

    Background subtraction without a separate training phase has become a critical task, because a sufficiently long and clean training sequence is usually unavailable, and people generally thirst for immediate detection results from the first frame of a video. Without a training phase, we propose a background subtraction method based on three-dimensional (3D) discrete wavelet transform (DWT). Static backgrounds with few variations along the time axis are characterized by intensity temporal consistency in the 3D space-time domain and, hence, correspond to low-frequency components in the 3D frequency domain. Enlightened by this, we eliminate low-frequency components that correspond to static backgrounds using the 3D DWT in order to extract moving objects. Owing to the multiscale analysis property of the 3D DWT, the elimination of low-frequency components in sub-bands of the 3D DWT is equivalent to performing a pyramidal 3D filter. This 3D filter brings advantages to our method in reserving the inner parts of detected objects and reducing the ringing around object boundaries. Moreover, we make use of wavelet shrinkage to remove disturbance of intensity temporal consistency and introduce an adaptive threshold based on the entropy of the histogram to obtain optimal detection results. Experimental results show that our method works effectively in situations lacking training opportunities and outperforms several popular techniques.

  18. EGFR and EGFRvIII undergo stress- and EGFR kinase inhibitor-induced mitochondrial translocalization: A potential mechanism of EGFR-driven antagonism of apoptosis

    Directory of Open Access Journals (Sweden)

    Ali-Osman Francis

    2011-03-01

    Full Text Available Abstract Background Epidermal growth factor receptor (EGFR plays an essential role in normal development, tumorigenesis and malignant biology of human cancers, and is known to undergo intracellular trafficking to subcellular organelles. Although several studies have shown that EGFR translocates into the mitochondria in cancer cells, it remains unclear whether mitochondrially localized EGFR has an impact on the cells and whether EGFRvIII, a constitutively activated variant of EGFR, undergoes mitochondrial transport similar to EGFR. Results We report that both receptors translocate into the mitochondria of human glioblastoma and breast cancer cells, following treatments with the apoptosis inducers, staurosporine and anisomycin, and with an EGFR kinase inhibitor. Using mutant EGFR/EGFRvIII receptors engineered to undergo enriched intracellular trafficking into the mitochondria, we showed that glioblastoma cells expressing the mitochondrially enriched EGFRvIII were more resistant to staurosporine- and anisomycin-induced growth suppression and apoptosis and were highly resistant to EGFR kinase inhibitor-mediated growth inhibition. Conclusions These findings indicate that apoptosis inducers and EGFR-targeted inhibitors enhance mitochondrial translocalization of both EGFR and EGFRvIII and that mitochondrial accumulation of these receptors contributes to tumor drug resistance. The findings also provide evidence for a potential link between the mitochondrial EGFR pathway and apoptosis.

  19. Lapatinib, a dual EGFR and HER2 tyrosine kinase inhibitor, downregulates thymidylate synthase by inhibiting the nuclear translocation of EGFR and HER2.

    Directory of Open Access Journals (Sweden)

    Hwang-Phill Kim

    Full Text Available BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI has been shown to exert a synergistic antitumor effect when combined with fluoropyrimidine. This synergy may be attributable to the downregulation of thymidylate synthase (TS, which is frequently overexpressed in fluoropyrimidine-resistant cancer cells. However, the molecular mechanism underlying the downregulation of TS has yet to be clearly elucidated. METHODOLOGY AND PRINCIPAL FINDINGS: In this study, we demonstrate that lapatinib, a dual TKI of EGFR and HER2 downregulates TS via inhibition of the nuclear translocation of EGFR and HER2. From our cDNA microarray experiments, we determined that a variety of nucleotide synthesis-related genes, including TS, were downregulated with lapatinib, and this was apparent in HER2-amplified cells. Targeted and pharmacologic inhibition assays confirmed that the dual inhibition of EGFR and HER2 is required for the more effective reduction of TS as compared to what was observed with gefitinib or trasutuzumab alone. Additionally, we determined that co-transfected EGFR and HER2 activate the TS gene promoter more profoundly than do either EGFR or HER2 alone. The translocation of EGFR and HER2 into the nucleus and the subsequent activation of the TS promoter were inhibited by lapatinib. CONCLUSIONS AND SIGNIFICANCE: These results demonstrate that lapatinib inhibits the nuclear translocation of EGFR and HER2 and downregulates TS, thus sensitizing cancer cells to fluoropyrimidine.

  20. A voltage-gated pore for translocation of tRNA

    Energy Technology Data Exchange (ETDEWEB)

    Koley, Sandip; Adhya, Samit, E-mail: nilugrandson@gmail.com

    2013-09-13

    Highlights: •A tRNA translocating complex was assembled from purified proteins. •The complex translocates tRNA at a membrane potential of ∼60 mV. •Translocation requires Cys and His residues in the Fe–S center of RIC6 subunit. -- Abstract: Very little is known about how nucleic acids are translocated across membranes. The multi-subunit RNA Import Complex (RIC) from mitochondria of the kinetoplastid protozoon Leishmania tropica induces translocation of tRNAs across artificial or natural membranes, but the nature of the translocation pore remains unknown. We show that subunits RIC6 and RIC9 assemble on the membrane in presence of subunit RIC4A to form complex R3. Atomic Force Microscopy of R3 revealed particles with an asymmetric surface groove of ∼20 nm rim diameter and ∼1 nm depth. R3 induced translocation of tRNA into liposomes when the pH of the medium was lowered to ∼6 in the absence of ATP. R3-mediated tRNA translocation could also be induced at neutral pH by a K{sup +} diffusion potential with an optimum of 60–70 mV. Point mutations in the Cys{sub 2}–His{sub 2} Fe-binding motif of RIC6, which is homologous to the respiratory Complex III Fe–S protein, abrogated import induced by low pH but not by K{sup +} diffusion potential. These results indicate that the R3 complex forms a pore that is gated by a proton-generated membrane potential and that the Fe–S binding region of RIC6 has a role in proton translocation. The tRNA import complex of L. tropica thus contains a novel macromolecular channel distinct from the mitochondrial protein import pore that is apparently involved in tRNA import in some species.

  1. Timing of translocation influences birth rate and population dynamics in a forest carnivore

    Science.gov (United States)

    Facka, Aaron N; Lewis, Jeffrey C.; Happe, Patricia; Jenkins, Kurt J.; Callas, Richard; Powell, Roger A.

    2016-01-01

    Timing can be critical for many life history events of organisms. Consequently, the timing of management activities may affect individuals and populations in numerous and unforeseen ways. Translocations of organisms are used to restore or expand populations but the timing of translocations is largely unexplored as a factor influencing population success. We hypothesized that the process of translocation negatively influences reproductive rates of individuals that are moved just before their birthing season and, therefore, the timing of releases could influence translocation success. Prior to reintroducing fishers (Pekania pennanti) into northern California and onto the Olympic Peninsula of Washington, we predicted that female fishers released in November and December (early) would have a higher probability of giving birth to kits the following March or April than females released in January, February, and March (late), just prior to or during the period of blastocyst implantation and gestation. Over four winters (2008–2011), we translocated 56 adult female fishers that could have given birth in the spring immediately after release. Denning rates, an index of birth rate, for females released early were 92% in California and 38% in Washington. In contrast, denning rates for females released late were 40% and 11%, in California and Washington, a net reduction in denning rate of 66% across both sites. To understand how releasing females nearer to parturition could influence population establishment and persistence, we used stochastic population simulations using three-stage Lefkovitch matrices. These simulations showed that translocating female fishers early had long-term positive influences on the mean population size and on quasi-extinction thresholds compared to populations where females were released late. The results from both empirical data and simulations show that the timing of translocation, with respect to life history events, should be considered during

  2. The Diffuse Supernova Neutrino Background

    CERN Document Server

    Beacom, John F

    2010-01-01

    The Diffuse Supernova Neutrino Background (DSNB) is the weak glow of MeV neutrinos and antineutrinos from distant core-collapse supernovae. The DSNB has not been detected yet, but the Super-Kamiokande (SK) 2003 upper limit on the electron antineutrino flux is close to predictions, now quite precise, based on astrophysical data. If SK is modified with dissolved gadolinium to reduce detector backgrounds and increase the energy range for analysis, then it should detect the DSNB at a rate of a few events per year, providing a new probe of supernova neutrino emission and the cosmic core-collapse rate. If the DSNB is not detected, then new physics will be required. Neutrino astronomy, while uniquely powerful, has proven extremely difficult -- only the Sun and the nearby Supernova 1987A have been detected to date -- so the promise of detecting new sources soon is exciting indeed.

  3. Bayesian Analysis of the Cosmic Microwave Background

    Science.gov (United States)

    Jewell, Jeffrey

    2007-01-01

    There is a wealth of cosmological information encoded in the spatial power spectrum of temperature anisotropies of the cosmic microwave background! Experiments designed to map the microwave sky are returning a flood of data (time streams of instrument response as a beam is swept over the sky) at several different frequencies (from 30 to 900 GHz), all with different resolutions and noise properties. The resulting analysis challenge is to estimate, and quantify our uncertainty in, the spatial power spectrum of the cosmic microwave background given the complexities of "missing data", foreground emission, and complicated instrumental noise. Bayesian formulation of this problem allows consistent treatment of many complexities including complicated instrumental noise and foregrounds, and can be numerically implemented with Gibbs sampling. Gibbs sampling has now been validated as an efficient, statistically exact, and practically useful method for low-resolution (as demonstrated on WMAP 1 and 3 year temperature and polarization data). Continuing development for Planck - the goal is to exploit the unique capabilities of Gibbs sampling to directly propagate uncertainties in both foreground and instrument models to total uncertainty in cosmological parameters.

  4. Background independence in a background dependent renormalization group

    CERN Document Server

    Labus, Peter; Slade, Zoë H

    2016-01-01

    Within the derivative expansion of conformally reduced gravity, the modified split Ward identities are shown to be compatible with the flow equations if and only if either the anomalous dimension vanishes or the cutoff profile is chosen to be power law. No solutions exist if the Ward identities are incompatible. In the compatible case, a clear reason is found for why Ward identities can still forbid the existence of fixed points; however, for any cutoff profile, a background independent (and parametrisation independent) flow equation is uncovered. Finally, expanding in vertices, the combined equations are shown generically to become either over-constrained or highly redundant beyond the six-point level.

  5. Nonequilibrium dynamics of an exactly solvable Ising-like model and protein translocation

    CERN Document Server

    Pelizzola, A

    2013-01-01

    Using an Ising-like model of protein mechanical unfolding, we introduce a diffusive dynamics on its exactly known free energy profile, reducing the nonequilibrium dynamics of the model to a biased random walk. As an illustration, the model is then applied to the protein translocation phenomenon, taking inspiration from a recent experiment on the green fluorescent protein pulled by a molecular motor. The average translocation time is evaluated exactly, and the analysis of single trajectories shows that translocation proceeds through an intermediate state, similar to that observed in the experiment.

  6. Variant Philadelphia translocations with different breakpoints in six chronic myeloid leukemia patients

    Directory of Open Access Journals (Sweden)

    Dilhan Kuru

    2011-09-01

    Full Text Available Objective: The Philadelphia (Ph chromosome, consisting of the t(9;22(q34;q11 translocation, is observed in ~90% of patients with chronic myeloid leukemia (CML. Variant Ph translocations are observed in 5%-10% of CML patients. In variant translocations 3 and possibly more chromosomes are involved. Herein we report 6 CML patients with variant Ph translocations.Materials and Methods: Bone marrow samples were examined using conventional cytogenetic meth ods. Fluorescence in situ hybridization (FISH with whole-chromosome paints and BCR-ABL 1D probes were used to confirm and/or complement the findings, and identify rearrangements beyond the resolution of conventional cytogenetic methods. Results: Variant Ph translocations in the 6 patients were as follows: t(7;22(p22;q11, t(9;22;15(q34;q11;q22, t(15;22(p11;q11, t(1;9;22;3(q24;q34;q11;q21, t(12;22(p13;q11, and t(4;8;9;22(q11;q13;q34;q11.Conclusion: Among the patients, 3 had simple and 3 had complex variant Ph translocations. Two of the presented cases had variant Ph chromosomes not previously described, 1 of which had a new complex Ph translocation involving chromosomes 1, 3, 9, 22, and t(1;9;22;3(q24;q34;q11;q21 apart from a clone with a classical Ph, and the other case had variant Ph translocation with chromosomes 4, 8, 9, and 22, and t(4;8;9;22(q11;q13;q34;q11 full complex translocation. Number of studies reported that some patients with variant Ph translocation were poor responders to imatinib. All of our patients with variant Ph translocations had suboptimal responses to imatinib, denoting a poor prognosis also. Variant Ph translocations may be important as they are associated with prognosis and therapy for CML patients.

  7. Quantifying the role of chaperones in protein translocation by computational modelling

    Directory of Open Access Journals (Sweden)

    Salvatore eAssenza

    2015-03-01

    Full Text Available The molecular chaperone Hsp70 plays a central role in the import of cytoplasmic proteins into organelles,driving their translocation by binding them from the organellar interior. Starting from the experimentally-determined structure of the E. coli Hsp70, we computed, by means of molecular simulations,the effective free-energy profile for substrate translocation uponchaperone binding. We then used the resulting free energy to quantitatively characterize the kinetics of the import process, whose comparison with unassisted translocation highlights the essential role played by Hsp70 in importing cytoplasmic proteins.

  8. Mechanisms of metalloregulation of an anion-translocating ATPase.

    Science.gov (United States)

    Rosen, B P; Bhattacharjee, H; Shi, W

    1995-02-01

    The ars (arsenical resistance) operon cloned from R-factor R773 has five genes that encode two repressor proteins, ArsR and ArsD, and three structural proteins, ArsA, ArsB, and ArsC. The ArsA and ArsB proteins form a membrane-bound pump that functions as an oxyanion-translocating ATPase. The substrates of the pump are the oxyanions arsenite or antimonite. The ArsC protein is an arsenate reductase that reduces arsenate to arsenite, which is subsequently pumped out of the cell. This review deals with the mechanism of transcriptional regulation by the ArsR repressor and allosteric regulation of the ArsA protein, the catalytic subunit of the pump. The chemical nature of the inducer plays an important role in regulation. In solution arsenite or antimonite exist as oxyanions and reacts with the cysteines in proteins. In both transcriptional regulation by the ArsR repressor and allosteric regulation of the ArsA ATPase, the ability of As(III) and Sb(III) to interact with the cysteines of the proteins, involves their action as effector.

  9. Influence of concentration polarization on DNA translocation through a nanopore

    Science.gov (United States)

    Zhai, Shengjie; Zhao, Hui

    2016-05-01

    Concentration polarization can be induced by the unique ion-perm selectivity of small nanopores, leading to a salt concentration gradient across nanopores. This concentration gradient can create diffusio-osmosis and induce an electric field, affecting ionic currents on DNA that translocates through a nanopore. Here this influence is theoretically investigated by solving the continuum Poisson-Nernst-Planck model for different salt concentrations, DNA surface charge densities, and pore properties. By implementing the perturbation method, we can explicitly compute the contribution of concentration polarization to the ionic current. The induced electric field by concentration polarization is opposite to the imposed electric field and decreases the migration current, and the induced diffusio-osmosis can decrease the convection current as well. Our studies suggest that the importance of the concentration polarization can be determined by the parameter λ /G where λ is the double-layer thickness and G is the gap size. When λ /G is larger than a critical value, the influence of concentration polarization becomes more prominent. This conclusion is supported by the studies on the dependence of the ionic current on salt concentration and pore properties, showing that the difference between two models with and without accounting for concentration polarization is larger for low salts and small pores, which correspond to larger λ /G .

  10. Increased RhoA translocation in aorta of diabetic rats

    Institute of Scientific and Technical Information of China (English)

    Jiping TANG; Ikuyo KUSAKA; Amber R MASSEY; Shadon ROLLINS; John H ZHANG

    2006-01-01

    Aim: To analyze RhoA expression and activation in the aorta of diabetic rats. Methods: Male SD rats (n=70) were divided into 2 groups: the diabetic group and the control group. Diabetes was induced by intravenous injection of streptozotocin (55 mg/kg). The Rats were studied 3 weeks after the induction of diabetes. Western blotting was used to measure the expression and activation of Rho. Results: Heart rate was measured 24 h/d; it decreased by 58±13 beats/min in the diabetic rats. Isometric tension showed that the contraction of diabetic aorta was significantly reduced compared with that of control aorta when stimulated by KCl and serotonin. The relaxation of the diabetic aorta was reduced when stimulated by acetylcholine. An enhanced RhoA translocation in the aortic tissues of diabetic rats was determined by a 90% increase in membrane-bound RhoA, indicating that the activation of RhoA is markedly increased in the diabetic aorta. Conclusion: Our data suggest that upregulated RhoA could be involved in the vascular dysfunction of diabetic rats.

  11. PARK7 protein translocating into spermatozoa mitochondria in Chinese asthenozoospermia.

    Science.gov (United States)

    Sun, Yi; Zhang, Wen-Jia; Zhao, Xin; Yuan, Ren-Pei; Jiang, Hui; Pu, Xiao-Ping

    2014-09-01

    PARK7 (DJ1) is a multifunctional oxidative stress response protein that protects cells against reactive oxygen species (ROS) and mitochondrial damage. PARK7 defects are known to cause various physiological dysfunctions, including infertility. Asthenozoospermia (AS), i.e. low-motile spermatozoa in the ejaculate, is a common cause of human male infertility. In this study, we found that downregulation of PARK7 resulted in increased levels of lipid peroxide and ROS, decreased mitochondrial membrane potential, and reduced mitochondrial complex I enzyme activity in the spermatozoa from AS patients. Furthermore, it was observed that PARK7 was translocated into the mitochondria of damaged spermatozoa in AS. Finally, we examined the oxidative state of PARK7 and the results demonstrated the enhancement of oxidation, expressed by increased sulfonic acid residues, the highest form of oxidation, as the sperm motility decreased. Taken together, these results revealed that PARK7 deficiency may increase the oxidative stress damage to spermatozoa. Our present findings open new avenues of therapeutic intervention targeting PARK7 for the treatment of AS.

  12. Bacterial Translocation – Impact on the Adipocyte Compartment

    Science.gov (United States)

    Kruis, Tassilo; Batra, Arvind; Siegmund, Britta

    2013-01-01

    Over the last decade it became broadly recognized that adipokines and thus the fat tissue compartment exert a regulatory function on the immune system. Our own group described the pro-inflammatory function of the adipokine leptin within intestinal inflammation in a variety of animal models. Following-up on this initial work, the aim was to reveal stimuli and mechanisms involved in the activation of the fat tissue compartment and the subsequent release of adipokines and other mediators paralleled by the infiltration of immune cells. This review will summarize the current literature on the possible role of the mesenteric fat tissue in intestinal inflammation with a focus on Crohn’s disease (CD). CD is of particular interest in this context since the transmural intestinal inflammation has been associated with a characteristic hypertrophy of the mesenteric fat, a phenomenon called “creeping fat.” The review will address three consecutive questions: (i) What is inducing adipocyte activation, (ii) which factors are released after activation and what are the consequences for the local fat tissue compartment and infiltrating cells; (iii) do the answers generated before allow for an explanation of the role of the mesenteric fat tissue within intestinal inflammation? With this review we will provide a working model indicating a close interaction in between bacterial translocation, activation of the adipocytes, and subsequent direction of the infiltrating immune cells. In summary, the models system mesenteric fat indicates a unique way how adipocytes can directly interact with the immune system. PMID:24432024

  13. Movilidad y desarrollo translocal en la Nicaragua (semi-rural

    Directory of Open Access Journals (Sweden)

    Griet Steel

    2012-08-01

    Full Text Available Este artículo pretende contribuir al debate sobre los vínculos entre la movilidad y el desarrollo, explorando el concepto de desarrollo translocal. Basado en trabajo de campo en los municipios de Matiguás y Muy Muy, éste analiza cómo la movilidad da forma a las estrategias de vida de los hogares (semi-rurales en Nicaragua, y explora cómo los diferentes miembros de un hogar utilizan la movilidad física como una estrategia de vida. Argumenta que los habitantes de áreas (semi-rurales consideran distintos tipos de movimientos como estrategias importantes para establecer enlaces entre personas y lugares, y para alcanzar un mejor bienestar en su comunidad natal. Al mismo tiempo muestra cómo la movilidad se forma en una arena de poder, lo que afecta su potencial. De esta manera, este artículo contribuye a un entendimiento dinámico y multidimensional de cómo los procesos de desarrollo dan forma a – y son formados por – la movilidad y la interconectividad.

  14. Markers of bacterial translocation in end-stage liver disease

    Institute of Scientific and Technical Information of China (English)

    Ioannis; Koutsounas; Garyfallia; Kaltsa; Spyros; I; Siakavellas; Giorgos; Bamias

    2015-01-01

    Bacterial translocation(BT) refers to the passage of viable bacteria or bacterial products from the intestinal lumen, through the intestinal epithelium, into the systemic circulation and extraintestinal locations. The three principal mechanisms that are thought to be involved in BT include bacterial overgrowth, disruption of the gut mucosal barrier and an impaired host defence.BT is commonly observed in liver cirrhosis and has been shown to play an important role in the pathogenesis of the complications of end stage liver disease, including infections as well as hepatic encephalopathy and hepatorenal syndrome. Due to the importance of BT in the natural history of cirrhosis, there is intense interest for the discovery of biomarkers of BT. To date, several such candidates have been proposed, which include bacterial DNA, soluble CD14, lipopolysaccharides endotoxin, lipopolysaccharide-binding protein, calprotectin and procalcitonin. Studies on the association of these markers with BT have demonstrated not only promising data but, oftentimes, contradictory results. As a consequence, currently, there is no optimal marker that may be used in clinical practice as a surrogate for the presence of BT.

  15. Absorption and translocation of nitrogen in rhizomes of Leymus chinensis.

    Science.gov (United States)

    Liu, Hongsheng; Liu, Huajie; Song, Youhong

    2011-03-15

    Leymus chinensis is a dominant species in the Inner Mongolia steppe, northern China. Plant growth in northern China grassland is often limited by low soil nitrogen availability. The objective of this study is to investigate whether rhizomes of Leymus chinensis are involved in the contribution of N uptake. The N concentration, (15)N concentration and (15)N proportion in roots, rhizomes and shoots after 48 h exposure of roots (L(root)) and rhizomes (L(rhizo)) separately and roots and rhizomes together (L(r+r)) to 0.1 mM (15)NH (4)(15)NO(3) solution were measured using root-splitting equipment and stable isotope ((15)N) techniques, respectively. The N content and dry mass were not affected by the labeling treatment. In contrast, the (15)N concentration in shoots, rhizomes and roots was significantly increased by the labeling in rhizomes, indicating that the inorganic nitrogen was absorbed via rhizomes from the solution and can be transported to other tissues, with preference to shoots rather than roots. Meanwhile, the absolute N absorption and translocation among compartments were also calculated. The N absorption via rhizomes was much smaller than via roots; however, the uptake efficiency per surface unit via rhizomes was greater than via roots. The capacity and high efficiency to absorb N nutrient via rhizomes enable plants to use transient nutrient supplies in the top soil surface.

  16. Silicon Nanopore Devices for DNA Translocation and Sequencing Studies

    Science.gov (United States)

    Ling, Sean

    2005-03-01

    In this talk, I will discuss the recent progress [1-3] in developing solid-state nanopore devices using silicon technology. We have demonstrated a novel technique for shaping nanopores in the range of 1-10 nm, using surface-tension-driven mass flow with single nanometer precision. This technique overcomes a major technical challenge in silicon technology. I will also discuss the current effort [3] in developing integrated nanopore silicon chips with electrically addressable nanopores. These devices are used for DNA translocation and sequencing studies. This work was done in collaboration with the group of Cees Dekker at TU-Delft with partial support from FOM and Guggenheim Foundation. The work at Brown was supported by NSF-NER and NSF-NIRT. [1] A.J. Storm, J.H. Chen, X.S. Ling, H. Zandbergen, and C. Dekker, ``Fabrication of Solid-State Nanopores with Single Nanometer Precision'', Nature Materials, 2, 537 (2003). [2] A.J. Storm, J.H. Chen, X.S. Ling, H. Zandbergen, and C. Dekker, ``Electron-Beam-Induced Deformations of SiO2 Nanostructures'', Journal of Applied Physics (submitted, 2004). [3] X.S. Ling, "Addressable nanopores and micropores" (patent pending).

  17. Successive site translocating inoculation potentiates DNA/recombinant vaccinia vaccination.

    Science.gov (United States)

    Ren, Yanqin; Wang, Na; Hu, Weiguo; Zhang, Xiaoyan; Xu, Jianqing; Wan, Yanmin

    2015-12-15

    DNA vaccines have advantages over traditional vaccine modalities; however the relatively low immunogenicity restrains its translation into clinical use. Further optimizations are needed to get the immunogenicity of DNA vaccine closer to the level required for human use. Here we show that intramuscularly inoculating into a different limb each time significantly improves the immunogenicities of both DNA and recombinant vaccinia vaccines during multiple vaccinations, compared to repeated vaccination on the same limb. We term this strategy successive site translocating inoculation (SSTI). SSTI could work in synergy with genetic adjuvant and DNA prime-recombinant vaccinia boost regimen. By comparing in vivo antigen expression, we found that SSTI avoided the specific inhibition of in vivo antigen expression, which was observed in the limbs being repeatedly inoculated. Employing in vivo T cell depletion and passive IgG transfer, we delineated that the inhibition was not mediated by CD8(+) T cells but by specific antibodies. Finally, by using C3(-/-) mouse model and in vivo NK cells depletion, we identified that specific antibodies negatively regulated the in vivo antigen expression primarily in a complement depended way.

  18. Stochastic backgrounds of relic gravitons: a theoretical appraisal

    CERN Document Server

    Giovannini, Massimo

    2010-01-01

    Stochastic backgrounds or relic gravitons, if ever detected, will constitute a prima facie evidence of physical processes taking place during the earliest stages of the evolution of the plasma. The essentials of the stochastic backgrounds of relic gravitons are hereby introduced and reviewed. The pivotal observables customarily employed to infer the properties of the relic gravitons are discussed both in the framework of the $\\Lambda$CDM paradigm as well as in neighboring contexts. The complementarity between experiments measuring the polarization of the Cosmic Microwave Background (such as, for instance, WMAP, Capmap, Quad, Cbi, just to mention a few) and wide band interferometers (e.g. Virgo, Ligo, Geo, Tama) is emphasized. While the analysis of the microwave sky strongly constrains the low-frequency tail of the relic graviton spectrum, wide-band detectors are sensitive to much higher frequencies where the spectral energy density depends chiefly upon the (poorly known) rate of post-inflationary expansion.

  19. Searching for a Stochastic Background of Gravitational Waves with LIGO

    CERN Document Server

    Abbott, R; Agresti, J; Ajith, P; Allen, B; Amin, R; Anderson, S B; Anderson, W G; Araya, M; Armandula, H; Ashley, M; Aston, S; Aulbert, C; Babak, S; Ballmer, S; Barish, B C; Barker, C; Barker, D; Barr, B; Barriga, P; Barton, M A; Bayer, K; Belczynski, K; Betzwieser, J; Beyersdorf, P; Bhawal, B; Bilenko, I A; Billingsley, G; Black, E; Blackburn, K; Blackburn, L; Blair, D; Bland, B; Bogue, L; Bork, R; Bose, S; Brady, P R; Braginsky, V B; Brau, J E; Brooks, A; Brown, D A; Bullington, A; Bunkowski, A; Buonanno, A; Burman, R; Busby, D; Byer, R L; Cadonati, L; Cagnoli, G; Camp, J B; Cannizzo, J; Cannon, K; Cantley, C A; Cao, J; Cardenas, L; Casey, M M; Cepeda, C; Charlton, P; Chatterji, S; Chelkowski, S; Chen, Y; Chin, D; Chin, E; Chow, J; Christensen, N; Cokelaer, T; Colacino, C N; Coldwell, R; Cook, D; Corbitt, T; Coward, D; Coyne, D; Creighton, J D E; Creighton, T D; Crooks, D R M; Cruise, A M; Cumming, A; Cutler, C; Dalrymple, J; D'Ambrosio, E; Danzmann, K; Davies, G; De Vine, G; De Bra, D; Degallaix, J; Dergachev, V; Desai, S; DeSalvo, R; Dhurandhar, S V; Di Credico, A; Dickson, J; Diederichs, G; Dietz, A; Doomes, E E; Drever, R W P; Dumas, J C; Dupuis, R J; Ehrens, P; Elliffe, E; Etzel, T; Evans, M; Evans, T; Fairhurst, S; Fan, Y; Fejer, M M; Finn, L S; Fotopoulos, N; Franzen, A; Franzen, K Y; Frey, R E; Fricke, T; Fritschel, P; Frolov, V V; Fyffe, M; Garofoli, J; Gholami, I; Giaime, J A; Giampanis, S; Goda, K; Goetz, E; Goggin, L; González, G; Gossler, S; Grant, A; Gras, S; Gray, C; Gray, M; Greenhalgh, J; Gretarsson, A M; Grimmett, D; Grosso, R; Grote, H; Grünewald, S; Günther, M; Gustafson, R; Hage, B; Hanna, C; Hanson, J; Hardham, C; Harms, J; Harry, G; Harstad, E; Hayler, T; Heefner, J; Heng, I S; Heptonstall, A; Heurs, M; Hewitson, M; Hild, S; Hindman, N; Hirose, E; Hoak, D; Hoang, P; Hosken, D; Hough, J; Howell, E; Hoyland, D; Hua, W; Huttner, S; Ingram, D; Ito, M; Itoh, Y; Ivanov, A; Jackrel, D; Johnson, B; Johnson, W W; Jones, D I; Jones, G; Jones, R; Ju, L; Kalmus, Peter Ignaz Paul; Kalogera, V; Kasprzyk, D; Katsavounidis, E; Kawabe, K; Kawamura, S; Kawazoe, F; Kells, W; Khalili, F Ya; Khan, A; Kim, C; King, P; Klimenko, S; Kokeyama, K; Kondrashov, V; Koranda, S; Kozak, D; Krishnan, B; Kwee, P; Lam, P K; Landry, M; Lantz, B; Lazzarini, A; Lee, B; Lei, M; Leonhardt, V; Leonor, I; Libbrecht, K; Lindquist, P; Lockerbie, N A; Lormand, M; Lubinski, M; Luck, H; Machenschalk, B; MacInnis, M; Mageswaran, M; Mailand, K; Malec, M; Mandic, V; Marka, S; Markowitz, J; Maros, E; Martin, I; Marx, J N; Mason, K; Matone, L; Mavalvala, N; McCarthy, R; McClelland, D E; McGuire, S C; McHugh, M; McKenzie, K; McNabb, J W C; Meier, T; Melissinos, A C; Mendell, G; Mercer, R A; Meshkov, S; Messaritaki, E; Messenger, C J; Meyers, D; Mikhailov, E; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Miyakawa, O; Mohanty, S; Moreno, G; Mossavi, K; Mow Lowry, C; Moylan, A; Mudge, D; Müller, G; Müller-Ebhardt, H; Mukherjee, S; Munch, J; Murray, P; Myers, E; Myers, J; Newton, G; Numata, K; O'Reilly, B; O'Shaughnessy, R; Ottaway, D J; Overmier, H; Owen, B J; Pan, Y; Papa, M A; Parameshwaraiah, V; Pedraza, M; Penn, S; Pitkin, M; Plissi, M V; Prix, R; Quetschke, V; Raab, F; Rabeling, D; Radkins, H; Rahkola, R; Rakhmanov, M; Rawlins, K; Ray-Majumder, S; Re, V; Rehbein, H; Reid, S; Reitze, D H; Ribichini, L; Riesen, R; Riles, K; Rivera, B; Robertson, D I; Robertson, N A; Robinson, C; Roddy, S; Rodríguez, A; Rogan, A M; Rollins, J; Romano, J D; Romie, J; Route, R; Rowan, S; Rüdiger, A; Ruet, L; Russell, P; Ryan, K; Sakata, S; Samidi, M; Sanchodela-Jordana, L; Sandberg, V; Sannibale, V; Saraf, S; Sarin, P; Sathyaprakash, B S; Sato, S; Saulson, P R; Savage, R; Schediwy, S; Schilling, R; Schnabel, R; Schofield, R; Schutz, B F; Schwinberg, P; Scott, S M; Seader, S E; Searle, A C; Sears, B; Seifert, F; Sellers, D; Sengupta, A S; Shawhan, P; Sheard, B; Shoemaker, D H; Sibley, A; Siemens, X; Sigg, D; Sintes, A M; Slagmolen, B; Slutsky, J; Smith, J; Smith, M R; Sneddon, P; Somiya, K; Speake, C; Spjeld, O; Strain, K A; Strom, D M; Stuver, A; Summerscales, T; Sun, K; Sung, M; Sutton, P J; Tanner, D B; Tarallo, M; Taylor, R; Thacker, J; Thorne, K A; Thorne, K S; Thüring, A; Tokmakov, K V; Torres, C; Torrie, C; Traylor, G; Trias, M; Tyler, W; Ugolini, D W; Ungarelli, C; Vahlbruch, H; Vallisneri, M; Varvella, M; Vass, S; Vecchio, A; Veitch, J; Veitch, P; Vigeland, S; Villar, A; Vorvick, C; Vyachanin, S P; Waldman, S J; Wallace, L; Ward, H; Ward, R; Watts, K; Webber, D; Weidner, A; Weinstein, A; Weiss, R; Wen, S; Wette, K; Whelan, J T; Whitbeck, D M; Whitcomb, S E; Whiting, B F; Wilkinson, C; Willems, P A; Willke, B; Wilmut, I; Winkler, W; Wipf, C C; Wise, S; Wiseman, A G; Woan, G; Woods, D; Wooley, R; Worden, J; Wu, W; Yakushin, I; Yamamoto, H; Yan, Z; Yoshida, S; Yunes, N; Zanolin, M; Zhang, L; Zhao, C; Zotov, N P; Zucker, M; Zur Mühlen, H; Zweizig, J

    2006-01-01

    The Laser Interferometer Gravitational-wave Observatory (LIGO) has performed the fourth science run, S4, with significantly improved interferometer sensitivities with respect to previous runs. Using data acquired during this science run, we place a limit on the amplitude of a stochastic background of gravitational waves. For a frequency independent spectrum, the new limit is $\\Omega_{\\rm GW} < 6.5 \\times 10^{-5}$. This is currently the most sensitive result in the frequency range 51-150 Hz, with a factor of 13 improvement over the previous LIGO result. We discuss complementarity of the new result with other constraints on a stochastic background of gravitational waves, and we investigate implications of the new result for different models of this background.

  20. A stochastic background of gravitational waves from hybrid preheating

    CERN Document Server

    García-Bellido, J; Garcia-Bellido, Juan; Figueroa, Daniel G.

    2006-01-01

    The process of reheating the universe after hybrid inflation is extremely violent. It proceeds through the nucleation and subsequent collision of large concentrations of energy density in bubble-like structures, which generate a significant fraction of energy in the form of gravitational waves. We study the power spectrum of the stochastic background of gravitational waves produced at reheating after hybrid inflation. We find that the amplitude could be significant for high-scale models, although the typical frequencies are well beyond what could be reached by planned gravitational wave observatories like LIGO, LISA or BBO. On the other hand, low-scale models could still produce a detectable stochastic background at frequencies accesible to those detectors. The discovery of such a background would open a new window into the very early universe.

  1. Component Separation of a Isotropic Gravitational Wave Background

    CERN Document Server

    Parida, Abhishek; Jhingan, Sanjay

    2015-01-01

    A Gravitational Wave Background (GWB) is expected in the universe from the superposition of a large number of unresolved astrophysical sources and phenomena in the early universe. Each component of the background (e.g., from primordial metric perturbations, binary neutron stars, milli-second pulsars etc.) has its own spectral shape. Many ongoing experiments aim to probe GWB at a variety of frequency bands. In the last two decades, using data from ground-based laser interferometric gravitational wave (GW) observatories, upper limits on GWB were placed in the frequency range of ~50-1000 Hz, considering one spectral shape at a time. However, one strong component can significantly enhance the estimated strength of another component. Hence, estimation of the amplitudes of the components with different spectral shapes should be done jointly. Here we propose a method for "component separation" of a statistically isotropic background, that can, for the first time, jointly estimate the amplitudes of many components an...

  2. HBsAg inhibits the translocation of JTB into mitochondria in HepG2 cells and potentially plays a role in HCC progression.

    Directory of Open Access Journals (Sweden)

    Yun-Peng Liu

    Full Text Available BACKGROUND AND AIMS: The expression of the jumping translocation breakpoint (JTB gene is upregulated in malignant liver tissues; however, JTB is associated with unbalanced translocations in many other types of cancer that suppress JTB expression. No comprehensive analysis on its function in human hepatocellular carcinoma (HCC has been performed to date. We aimed to define the biological consequences for interaction between JTB and HBsAg in HCC cell lines. METHODS: We employed the stable transfection to establish small HBsAg expressing HepG2 cell line, and stably silenced the JTB expression using short hairpin RNA in HepG2 cell line. The effects of JTB and small HBsAg in vitro were determined by assessing cell apoptosis and motility. RESULTS: Silencing of JTB expression promoted cancer cell motility and reduced cell apoptosis, which was significantly enhanced by HBs expression. Expression of HBsAg inhibited the translocation of JTB to the mitochondria. Furthermore, silencing of the JTB resulted in an increase in the phosphorylation of p65 in HepG2 cells and HepG2-HBs cells, whereas HBsAg expression decreased the phosphorylation of p65. The silencing of JTB in HepG2-HBs cells conferred increased advantages in cell motility and anti-apoptosis. CONCLUSION: HBsAg inhibited the translocation of JTB to the mitochondria and decreased the phosphorylation of p65 through the interaction with JTB, After JTB knockdown, HBsAg exhibited a stronger potential to promote tumor progression. Our data suggested that JTB act as a tumor suppressor gene in regards to HBV infection and its activation might be applied as a therapeutic strategy for in control of HBV related HCC development.

  3. Tailored ß-cyclodextrin blocks the translocation pores of binary exotoxins from C. botulinum and C. perfringens and protects cells from intoxication.

    Directory of Open Access Journals (Sweden)

    Ekaterina M Nestorovich

    Full Text Available BACKGROUND: Clostridium botulinum C2 toxin and Clostridium perfringens iota toxin are binary exotoxins, which ADP-ribosylate actin in the cytosol of mammalian cells and thereby destroy the cytoskeleton. C2 and iota toxin consists of two individual proteins, an enzymatic active (A- component and a separate receptor binding and translocation (B- component. The latter forms a complex with the A-component on the surface of target cells and after receptor-mediated endocytosis, it mediates the translocation of the A-component from acidified endosomal vesicles into the cytosol. To this end, the B-components form heptameric pores in endosomal membranes, which serve as translocation channels for the A-components. METHODOLOGY/PRINCIPAL FINDINGS: Here we demonstrate that a 7-fold symmetrical positively charged ß-cyclodextrin derivative, per-6-S-(3-aminomethylbenzylthio-ß-cyclodextrin, protects cultured cells from intoxication with C2 and iota toxins in a concentration-dependent manner starting at low micromolar concentrations. We discovered that the compound inhibited the pH-dependent membrane translocation of the A-components of both toxins in intact cells. Consistently, the compound strongly blocked transmembrane channels formed by the B-components of C2 and iota toxin in planar lipid bilayers in vitro. With C2 toxin, we consecutively ruled out all other possible inhibitory mechanisms showing that the compound did not interfere with the binding of the toxin to the cells or with the enzyme activity of the A-component. CONCLUSIONS/SIGNIFICANCE: The described ß-cyclodextrin derivative was previously identified as one of the most potent inhibitors of the binary lethal toxin of Bacillus anthracis both in vitro and in vivo, implying that it might represent a broad-spectrum inhibitor of binary pore-forming exotoxins from pathogenic bacteria.

  4. ATP depletion induces translocation of STIM1 to puncta and formation of STIM1-ORAI1 clusters: translocation and re-translocation of STIM1 does not require ATP.

    Science.gov (United States)

    Chvanov, Michael; Walsh, Ciara M; Haynes, Lee P; Voronina, Svetlana G; Lur, Gyorgy; Gerasimenko, Oleg V; Barraclough, Roger; Rudland, Philip S; Petersen, Ole H; Burgoyne, Robert D; Tepikin, Alexei V

    2008-11-01

    Depletion of the endoplasmic reticulum (ER) calcium store triggers translocation of stromal interacting molecule one (STIM1) to the sub-plasmalemmal region and formation of puncta-structures in which STIM1 interacts and activates calcium channels. ATP depletion induced the formation of STIM1 puncta in PANC1, RAMA37, and HeLa cells. The sequence of events triggered by inhibition of ATP production included a rapid decline of ATP, depletion of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P(2)) and a slow calcium leak from the ER followed by formation of STIM1 puncta. STIM1 puncta induced by ATP depletion were co-localized with clusters of ORAI1 channels. STIM1-ORAI1 clusters that developed as a result of ATP depletion were very poor mediators of Ca(2+) influx. Re-translocation of STIM1 from puncta back to the ER was observed during total ATP depletion. We can therefore conclude that STIM1 translocation and re-translocation as well as formation of STIM1-ORAI1 clusters occur in an ATP-independent fashion and under conditions of PI(4,5)P(2) depletion.

  5. SIRT1 interacts with and protects glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from nuclear translocation: Implications for cell survival after irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Hyun-Yoo [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Laboratory of Biochemistry, School of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Woo, Seon Rang; Shen, Yan-Nan; Yun, Mi Yong; Shin, Hyun-Jin; Park, Eun-Ran; Kim, Su-Hyeon; Park, Jeong-Eun; Ju, Yeun-Jin; Hong, Sung Hee; Hwang, Sang-Gu [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Cho, Myung-Haing [Laboratory of Toxicology, College of Veterinary Medicine, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, Joon, E-mail: joonkim@korea.ac.kr [Laboratory of Biochemistry, School of Life Sciences and Biotechnology, Korea University, Seoul 136-713 (Korea, Republic of); Lee, Kee-Ho, E-mail: khlee@kirams.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer SIRT1 serves to retain GAPDH in the cytosol, preventing GAPDH nuclear translocation. Black-Right-Pointing-Pointer When SIRT1 is depleted, GAPDH translocation occurs even in the absence of stress. Black-Right-Pointing-Pointer Upon irradiation, SIRT1 interacts with GAPDH. Black-Right-Pointing-Pointer SIRT1 prevents irradiation-induced nuclear translocation of GAPDH. Black-Right-Pointing-Pointer SIRT1 presence rather than activity is essential for inhibiting GAPDH translocation. -- Abstract: Upon apoptotic stimulation, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a cytosolic enzyme normally active in glycolysis, translocates into the nucleus and activates an apoptotic cascade therein. In the present work, we show that SIRT1 prevents nuclear translocation of GAPDH via interaction with GAPDH. SIRT1 depletion triggered nuclear translocation of cytosolic GAPDH even in the absence of apoptotic stress. Such translocation was not, however, observed when SIRT1 enzymatic activity was inhibited, indicating that SIRT1 protein per se, rather than the deacetylase activity of the protein, is required to inhibit GAPDH translocation. Upon irradiation, SIRT1 prevented irradiation-induced nuclear translocation of GAPDH, accompanied by interaction of SIRT1 and GAPDH. Thus, SIRT1 functions to retain GAPDH in the cytosol, protecting the enzyme from nuclear translocation via interaction with these two proteins. This serves as a mechanism whereby SIRT1 regulates cell survival upon induction of apoptotic stress by means that include irradiation.

  6. Family Background and Educational Choices

    DEFF Research Database (Denmark)

    McIntosh, James; D. Munk, Martin

    We examine the participation in secondary and tertiary education of five cohorts of Danish males and females who were aged twenty starting in 1982 and ending in 2002. We find that the large expansion of secondary education in this period was characterized by a phenomenal increase in gymnasium...... enrollments, especially for females. Not only did the educational opportunities for individuals with disadvantaged backgrounds improve absolutely, but their relative position also improved. A similarly dramatic increase in attendance at university for the period 1985-2005 was found for these cohorts when...

  7. Particle propagation in cosmological backgrounds

    CERN Document Server

    Arteaga, Daniel

    2007-01-01

    We study the quantum propagation of particles in cosmological backgrounds, by considering a doublet of massive scalar fields propagating in an expanding universe, possibly filled with radiation. We focus on the dissipative effects related to the expansion rate. At first order, we recover the expected result that the decay rate is determined by the local temperature. Beyond linear order, the decay rate has an additional contribution governed by the expansion parameter. This latter contribution is present even for stable particles in the vacuum. Finally, we analyze the long time behaviour of the propagator and briefly discuss applications to the trans-Planckian question.

  8. Rigidity of the subunit interfaces of the trimeric glutamate transporter GItT during translocation

    NARCIS (Netherlands)

    Groeneveld, Maarten; Slotboom, Dirk-Jan

    2007-01-01

    Glutamate transporters are trimeric membrane proteins in which each protomer contains a separate translocation path. To determine whether structural rearrangements take place at the subunit interfaces during transport, intersubunit disulfide bridges were introduced in the bacterial transporter GltT.

  9. Translocation detection in lymphoma diagnosis by split-signal FISH: A standardised approach

    NARCIS (Netherlands)

    A. van Rijk (Anke); D. Mason (David); M. Jones (Marta); J. Cabeçadas (José); E. Crespo; J.C. Cigudosa (Juan Cruz); J.F. Garcia (Juan Fernando); L. Leoncini (Lorenzo); M. Cocco (Mario); M.-L. Hansmann (Martin-Leo); A. Mottok (Anja); C.C. Bergman (Christiane Copie); M. Baia (Maryse); D. Anagnostou (Dimitra); E. Pouliou (Evi); N. Dutoit (Nadia); M.H. Christiansen (Mette Hjøllund); T.S. Poulsen (T.); S.H. Matthiesen (Steen Hauge); J.J.M. van Dongen (Jacques); J.H.J.M. van Krieken (Han)

    2008-01-01

    textabstractLymphomas originating from the lymphatic system comprise about 30 entities classified according to the World Health Organization (WHO). The histopathological diagnosis is generally considered difficult and prone to mistakes. Since non-random chromosomal translocations are specifically in

  10. Kinesin-1 Translocation along Human Breast Cancer Cell Microtubules in Vitro

    Science.gov (United States)

    Shojania Feizabadi, Mitra; Jun, Yonggun

    2015-03-01

    A principle approach to better understand intra-cellular microtubule based transport is to study such it in vitro. Such in vitro examinations have predominantly used microtubules polymerized from bovine brain tubulin, but motor function can also in principle be affected by the specific tubulin isotypes present in different cells. The human breast cancer cells carry different beta tubulin isotype distribution. However, it is entirely unknown whether transport along the microtubules is different in these cells. In this work we have characterized, for the first time, the translocation specifications of kinesin-1 along human breast cancer cell microtubules polymerized in vitro. We found that as compared with the translocation along bovine brain microtubules, kinesin-1 shows a fifty percent shorter processive run length and slightly slower velocity under similar experimental conditions. These first time results support the regulatory role of tubulin isotypes in regards to motor protein translocations, and quantify the translocation specifications of kinesin-1 along microtubules of human breast cancer cells.

  11. Label-free discrimination of membrane-translocating peptides on porous silicon microfluidic biosensors.

    Science.gov (United States)

    Li, Zhen; Luo, Qiaohui; Wu, Jianmin

    2016-11-01

    A label-free optical sensor was constructed by integrating electrochemically etched porous silicon (pSi) and supported phospholipid bilayers in a microfluidic chip. The translocation of peptides through the phospholipid bilayers could induce a red shift in effective optical thickness of the pSi layer, which could be monitored by reflective interferometric Fourier transform spectroscopy. By measuring the kinetic data of membrane translocating on the phospholipid bilayers/pSi chip, the relationship between the behavior of membrane-translocating peptides (MTPs) and translocating mechanism was established. With these optical data, MTPs with different action modes on the cell membrane can be correctly discriminated. The bio-functionalized microfluidic sensor will provide a reliable and cost-effective platform to study the transmembrane behavior of peptides, which is of great importance in the MTP screening and peptide function study.

  12. Na+-K+ pump location and translocation during muscle contraction  in rat skeletal muscle

    DEFF Research Database (Denmark)

    Kristensen, Michael; Rasmussen, Martin Krøyer; Juel, Carsten

    2008-01-01

    Muscle contraction may up-regulate the number of Na+-K+ pumps in the plasma membrane by translocation of subunits. Since there is still controversy about where this translocation takes place from and if it takes place at all, the present study used different techniques to characterize...... subunits were associated with Cav-3 in soleus, extensor digitorum longus, and mixed muscles, respectively. For the a2, the corresponding values were 17%, 5% and 16%. In conclusion; muscle contraction induces translocation of the a subunits, which is suggested to be caused partly by structural changes...... the translocation. Electrical stimulation and biotin labeling of rat muscle revealed a 40% and 18% increase in the amounts of the Na+-K+ pump a2 subunit and caveolin-3 (Cav-3), respectively, in the sarcolemma. Exercise induced a 36% and 19% increase in the relative amounts of the a2 subunit and Cav-3, respectively...

  13. Complex Variant t(9;22 Chromosome Translocations in Five Cases of Chronic Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Ana Valencia

    2009-01-01

    Full Text Available The Philadelphia (Ph1 chromosome arising from the reciprocal t(9;22 translocation is found in more than 90% of chronic myeloid leukemia (CML patients and results in the formation of the chimeric fusion gene BCR-ABL. However, a small proportion of patients with CML have simple or complex variants of this translocation, involving various breakpoints in addition to 9q34 and 22q11. We report five CML cases carrying variant Ph translocations involving both chromosomes 9 and 22 as well as chromosomes 3, 5, 7, 8, or 10. G-banding showed a reciprocal three-way translocation involving 3q21, 5q31, 7q32, 8q24, and 10q22 bands. BCR-ABL fusion signal on der(22 was found in all of the cases by FISH.

  14. Transport of radiocesium in mycelium and its translocation to fruitbodies of a saprophytic macromycete

    Energy Technology Data Exchange (ETDEWEB)

    Bazala, Michal A.; Golda, Katarzyna [Isotope Laboratory, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw (Poland); Bystrzejewska-Piotrowska, Grazyna [Isotope Laboratory, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw (Poland)], E-mail: byst@biol.uw.edu.pl

    2008-07-15

    We present a new protocol to study fluxes of radionuclides and other xenobiotics in saprophytic fungi. This simple method has successfully been used to evaluate transport of radiocesium in hyphae of Pleurotus eryngii and its translocation to fruitbodies.

  15. Translocation and banding of Aleutian Canada geese in the western Aleutian Islands in 1990

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In August 1990, 110 Aleutian Canada geese (Branta canadensis leucopareia) were captured and banded at Buldir Island. Twenty-five of these geese were translocated to...

  16. Crystal Structures of EF-G-Ribosome Complexes Trapped in Intermediate States of Translocation

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Jie; Lancaster, Laura; Donohue, John Paul; Noller, Harry F. [UCSC

    2013-11-12

    Translocation of messenger and transfer RNA (mRNA and tRNA) through the ribosome is a crucial step in protein synthesis, whose mechanism is not yet understood. The crystal structures of three Thermus ribosome-tRNA-mRNA–EF-G complexes trapped with β,γ-imidoguanosine 5'-triphosphate (GDPNP) or fusidic acid reveal conformational changes occurring during intermediate states of translocation, including large-scale rotation of the 30S subunit head and body. In all complexes, the tRNA acceptor ends occupy the 50S subunit E site, while their anticodon stem loops move with the head of the 30S subunit to positions between the P and E sites, forming chimeric intermediate states. Two universally conserved bases of 16S ribosomal RNA that intercalate between bases of the mRNA may act as “pawls” of a translocational ratchet. These findings provide new insights into the molecular mechanism of ribosomal translocation.

  17. RUVBL2, a novel AS160-binding protein, regulates insulin-stimulated GLUT4 translocation

    Institute of Scientific and Technical Information of China (English)

    Xiangyang Xie; Yu Chen; Peng Xue; Yong Fan; Yongqiang Deng; Gong Peng; Fuquan Yang; Tao Xu

    2009-01-01

    In fat and muscle cells, insulin-stimulated glucose uptake is mainly mediated by glucose transporter 4 (GLUT4), which translocates from intracellular compartments to the cell surface in response to insulin stimulation. AS160 is one of the substrates of Akt and plays important roles in insulin-regulated GLUT4 translocation. In this study, RuvB-like protein 2 (RUVBL2) is identified as a new AS160-binding protein using mammalian tandem affinity purification (TAP) combined with mass spectrometry. In 3T3-L1 adipocytes, RUVBL2 is highly expressed and is mainly distrib-uted in the cytosol. Depletion of RUVBL2 in adipocytes inhibits insufin-stimulated GLUT4 translocation and glucose uptake through reducing insulin-stimulated AS160 phosphorylation. However, introduction of human RUVBL2 can reverse this inhibitory effect. These data suggest that RUVBL2 plays an important role in insulin-stimulated GLUT4 translocation through its interaction with AS160.

  18. Xp11 translocation renal cell carcinoma (RCC): extended immunohistochemical profile emphasizing novel RCC markers.

    Science.gov (United States)

    Argani, Pedram; Hicks, Jessica; De Marzo, Angelo M; Albadine, Roula; Illei, Peter B; Ladanyi, Marc; Reuter, Victor E; Netto, George J

    2010-09-01

    Xp11 translocation renal cell carcinoma (RCC) harbor various TFE3 gene fusions, and are known to underexpress epithelial immunohistochemical (IHC) markers such as cytokeratin and EMA relative to usual adult type RCC; however, their profile in reference to other IHC markers that are differentially expressed in other subtypes of RCC has not been systematically assessed. Few therapeutic targets have been identified in these aggressive cancers. We created 2 tissue microarrays (TMA) containing five 1.4-mm cores from each of 21 Xp11 translocation RCC (all confirmed by TFE3 IHC, 6 further confirmed by genetics), 7 clear cell RCC (CCRCC), and 6 papillary RCC (PRCC). These TMA were labeled for a panel of IHC markers. In contrast to earlier published data, Xp11 translocation RCC frequently expressed renal transcription factors PAX8 (16/21 cases) and PAX2 (14/21 cases), whereas only 1 of 21 cases focally expressed MiTF and only 5 of 21 overexpressed p21. Although experimental data suggest otherwise, Xp11 translocation RCC did not express WT-1 (0/21 cases). Although 24% of Xp11 translocation RCC expressed HIF-1alpha (like CCRCC), unlike CCRCC CA IX expression was characteristically only focal (mean 6% cell labeling) in Xp11 translocation RCC. Other markers preferentially expressed in CCRCC or PRCC, such as HIG-2, claudin 7, and EpCAM, yielded inconsistent results in Xp11 translocation RCC. Xp11 translocation RCC infrequently expressed Ksp-cadherin (3/21 cases) and c-kit (0/21 cases), markers frequently expressed in chromophobe RCC. Using an H-score that is the product of intensity and percentage labeling, Xp11 translocation RCC expressed higher levels of phosphorylated S6, a measure of mTOR pathway activation (mean H score=88), than did CCRCC (mean H score=54) or PRCC (mean H score=44). In conclusion, in contrast to prior reports, Xp11 translocation RCC usually express PAX2 and PAX8 but do not usually express MiTF. Although they may express HIF-1alpha, they only focally

  19. Auditory intensity processing: Effect of MRI background noise.

    Science.gov (United States)

    Angenstein, Nicole; Stadler, Jörg; Brechmann, André

    2016-03-01

    Studies on active auditory intensity discrimination in humans showed equivocal results regarding the lateralization of processing. Whereas experiments with a moderate background found evidence for right lateralized processing of intensity, functional magnetic resonance imaging (fMRI) studies with background scanner noise suggest more left lateralized processing. With the present fMRI study, we compared the task dependent lateralization of intensity processing between a conventional continuous echo planar imaging (EPI) sequence with a loud background scanner noise and a fast low-angle shot (FLASH) sequence with a soft background scanner noise. To determine the lateralization of the processing, we employed the contralateral noise procedure. Linearly frequency modulated (FM) tones were presented monaurally with and without contralateral noise. During both the EPI and the FLASH measurement, the left auditory cortex was more strongly involved than the right auditory cortex while participants categorized the intensity of FM tones. This was shown by a strong effect of the additional contralateral noise on the activity in the left auditory cortex. This means a massive reduction in background scanner noise still leads to a significant left lateralized effect. This suggests that the reversed lateralization in fMRI studies with loud background noise in contrast to studies with softer background cannot be fully explained by the MRI background noise.

  20. Translocation of Single Polymer Chain from Nanopore on a Membrane: Solvent Effect

    Institute of Scientific and Technical Information of China (English)

    GU Fang; WANG Hai-Jun

    2005-01-01

    @@ We investigate the translocation of single polymer chain through a nanopore located on a membrane with different solvents in the two sides of the membrane. For the case under study, the effect of solvents on the translocation dynamics is significant, and as a result, the mean first passage time shortens remarkably compared with that calculated in the case of good solvents on both the sides of the membrane. In addition, we also discuss the condition such that the present result holds true.

  1. DNA translocation across protein channels: How does a polymer worm through a hole?

    Science.gov (United States)

    Muthukumar, M.

    2001-03-01

    Free energy barriers control the translocation of polymers through narrow channels. Based on an analogy with the classical nucleation and growth process, we have calculated the translocation time and its dependencies on the length, stiffness, and sequence of the polymer, solution conditions, and the strength of the driving electrochemical potential gradient. Our predictions will be compared with experimental results and prospects of reading polymer sequences.

  2. Effect of cisapride on intestinal bacterial and endotoxin translocation in cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Shun-Cai Zhang; Wei Wang; Wei-Ying Ren; Bo-Ming He; Kang Zhou; Wu-Nan Zhu

    2003-01-01

    AIM: To investigate the effects of cisapride on intestinal bacterial overgrowth (IBO), bacterial and endotoxin translocation, intestinal transit and permeability in cirrhotic rats.METHODS: All animals were assessed with variables including bacterial and endotoxin translocation, intestinal bacterial overgrowth, intestinal transit and permeability.Bacterial translocation (BT) was assessed by bacterial culture of MLN, liver and spleen, IBO by a jejunal bacterial count of the specific organism, intestinal permeability by determination of the 24-hour urinary 99mTc-DTPA excretion and intestinal transit by measurement of the distribution of 51Cr in the intestine.RESULTS: Bacterial translocation (BT) and IBO was found in 48 % and 80 % cirrhotic rats respectively and none in control rats. Urinary excretion of 99mTc-DTPA in cirrhotic rats with BT (22.2±7.8) was greater than these without BT (10.5±2.9). Intestinal transit (geometric center ratio) was significantly delayed in cirrhotic rats (0.31±0.06) and further more delayed in cirrhotic rats with BT (0.24±0.06) than these without BT (0.38±0.11). Cirrhotic rats with IBO had significantly higher rates of intestinal bacterial and endotoxin translocation, slower intestinal transit time and higher intestinal permeability than those without IBO. It was also found that BT was closely associated with IBO and the injury of intestinal barrier. Compared with the placebo group,cisapride-treated rats had lower rates of bacterial/endotoxin translocation and IBO, which was closely associated with increased intestinal transit and improved intestinal permeability by cisapride.CONCLUSION: These results indicate that endotoxin and bacterial translocation in cirrhotic rats may be attributed to IBO and increased intestinal permeability. Cisapride that accelerates intestinal transit and improve intestinal permeability might be helpful in preventing intestinal bacterial and endotoxin translocation.

  3. Quantized current blockade and hydrodynamic correlations in biopolymer translocation through nanopores: evidence from multiscale simulations

    CERN Document Server

    Bernaschi, Massimo; Succi, Sauro; Fyta, Maria; Kaxiras, Efthimios

    2008-01-01

    We present a detailed description of biopolymer translocation through a nanopore in the presence of a solvent, using an innovative multi-scale methodology which treats the biopolymer at the microscopic scale as combined with a self-consistent mesoscopic description for the solvent fluid dynamics. We report evidence for quantized current blockade depending on the folding configuration and offer detailed information on the role of hydrodynamic correlations in speeding-up the translocation process.

  4. Maternal transmission of translocation 2;21 associated with Down's syndrome.

    OpenAIRE

    Kotwaliwale, S V; Dicholkar, V V; Motashaw, N D

    1991-01-01

    An unusual 2;21 translocation associated with Down's syndrome is reported. The proband was a 3 year old boy, clinically diagnosed as having Down's syndrome and with a family history of Down's syndrome. Maternal age at the time of study was 28 years. Out of the four sibs with Down's syndrome three had died. Two pregnancies ended in first trimester miscarriage. The proband was found to have trisomy 21 associated with a 2;21 translocation inherited from his mother.

  5. Prenatal Diagnosis of Rare Familial Unbalanced Translocation of Chromosomes 7 and 12

    Directory of Open Access Journals (Sweden)

    Berrin Tezcan

    2015-01-01

    Full Text Available Case Details. We report rare familial unbalanced translocation of chromosomes 7 and 12, which was diagnosed prenatally at 20+3 weeks of gestation. Woman’s partner had been tested in the past and was found to be a carrier of a balanced translocation; his karyotype showed a balanced reciprocal translocation of 46, XY, t(7;12(q34;q24,32. Partner’s brother had an unbalanced form of the translocation with severe learning disability. The diagnosis of the anomaly was based on two- and three-dimensional ultrasound and microarray analysis. Ultrasonography findings included fetal microcephaly and alobar holoprosencephaly, dysmorphic face (flat occiput, absent nasal bone, microphthalmia, hypotelorism, and single nostril, and hyperechogenic bowel. Genome-wide array analysis and cytogenetic results from the amniotic fluid showed unbalanced translocation in chromosomes 7 and 12 with deletion of an approximately 16.5 Mb and a duplication of 6.1 Mb, respectively, Arr 7q34q36.3(142,668,576-159,161,648x1,12q24.32q24.33(127,708,720-133,777,560x3, karyotype (der (7 t(7;12 (q34;q24pat. This unbalanced translocation was due to the segregation of the father’s balanced translocation. In this particular case, the recurrence of an unbalanced translocation in the subsequent pregnancies is estimated to be 20%. Understanding the individuals’ phenotype in association with the gain and loss of copy number is important and can further provide us with information on that particular region of the named chromosomes.

  6. Determinants of the rate of mRNA translocation in bacterial protein synthesis.

    Science.gov (United States)

    Borg, Anneli; Ehrenberg, Måns

    2015-05-08

    Studying the kinetics of translocation of mRNA and tRNAs on the translating ribosome is technically difficult since the rate-limiting steps involve large conformational changes without covalent bond formation or disruption. Here, we have developed a unique assay system for precise estimation of the full translocation cycle time at any position in any type of open reading frame (ORF). Using a buffer system optimized for high accuracy of tRNA selection together with high concentration of elongation factor G, we obtained in vivo compatible translocation rates. We found that translocation was comparatively slow early in the ORF and faster further downstream of the initiation codon. The maximal translocation rate decreased from the in vivo compatible value of 30 s(-1) at 1 mM free Mg2+ concentration to the detrimentally low value of 1 s(-1) at 6 mM free Mg2+ concentration. Thus, high and in vivo compatible accuracy of codon translation, as well as high and in vivo compatible translocation rate, required a remarkably low Mg2+ concentration. Finally, we found that the rate of translocation deep inside an ORF was not significantly affected upon variation of the standard free energy of interaction between a 6-nt upstream Shine-Dalgarno (SD)-like sequence and the anti-SD sequence of 16S rRNA in a range of 0-6 kcal/mol. Based on these experiments, we discuss the optimal choice of Mg2+ concentration for maximal fitness of the living cell by taking its effects on the accuracy of translation, the peptide bond formation rate and the translocation rate into account.

  7. Translocator protein mediates the anxiolytic and antidepressant effects of midazolam.

    Science.gov (United States)

    Qiu, Zhi-Kun; Li, Ming-Sheng; He, Jia-Li; Liu, Xu; Zhang, Guan-Hua; Lai, Sha; Ma, Jian-Chun; Zeng, Jia; Li, Yan; Wu, Hong-Wei; Chen, Yong; Shen, Yong-Gang; Chen, Ji-Sheng

    2015-12-01

    The translocator protein (18 kDa) (TSPO) plays an important role in stress-related disorders, such as anxiety, depression and post-traumatic stress disorder (PTSD), caused by neurosteroids (e.g. allopregnanolone). The present study sought to evaluate the significance of TSPO in anxiolytic and antidepressant effects induced by midazolam. The animals were administrated midazolam (0.25, 0.5 and 1 mg/kg, i.p.) and subjected to behavioral tests, including Vogel-type conflict test, elevated plus-maze test, forced swimming test. Midazolam produced anxiolytic- and antidepressant-like effects Vogel-type conflict test (1 mg/kg, i.p.), elevated plus-maze test (0.5 and 1 mg/kg, i.p.), and forced swimming test (0.5 and 1 mg/kg, i.p.). These effects of Midazolam were totally blocked by the TSPO antagonist PK11195 (3 mg/kg, i.p.). To evaluate the role of allopregnanolone in the anxiolytic- and antidepressant-like effects of midazolam, the animals were decapitated at the end of the behavioral tests. The allopregnanolone levels of the prefrontal cortex and hippocampus were measured by enzyme-linked immunosorbent assay (ELISA). The allopregnanolone level of the prefrontal cortex and hippocampus was increased by midazolam (0.5, 1 mg/kg, i.p.) and the increase was reversed by PK11195 (3 mg/kg, i.p.). Overall, the results indicated that the anxiolytic- and antidepressant-like effects of midazolam were mediated by TSPO, via stimulation of allopregnanolone biosynthesis.

  8. The Semiflexible Polymer Translocation into Laterally Unbounded Region between Two Parallel Flat Membranes

    Directory of Open Access Journals (Sweden)

    Zhi-Yong Yang

    2016-09-01

    Full Text Available Using the dynamic Monte Carlo method, we investigate dynamics of semiflexible polymer translocation through a nanopore into laterally unbounded region between two parallel flat membranes with separation R in presence of an electric field inside the pore. The average translocation time τ initially decreases rapidly with increase of R in the range of R < 10 and then almost keeps constant for R ≥ 10, and the decline range increases with increase of dimensionless bending stiffness κ. We mainly study the effect of chain length N, κ and electric field strength E on the translocation process for R = 5. The translocation dynamics is significantly altered in comparison to an unconfined environment. We find τ ~ Nα, where the exponent α increases with increase of E for small κ. α initially increases slowly with increase of E and then keeps constant for moderate κ. α decreases with increase of E for large κ. However, α decreases with increase of κ under various E. In addition, we find τ ~ κβ. β decreases with increase of N under various E. These behaviors are interpreted in terms of the probability distribution of translocation time and the waiting time of an individual monomer segment passing through the pore during translocation.

  9. Gut Microbial Translocation in Critically Ill Children and Effects of Supplementation with Pre- and Pro Biotics

    Directory of Open Access Journals (Sweden)

    Paola Papoff

    2012-01-01

    Full Text Available Bacterial translocation as a direct cause of sepsis is an attractive hypothesis that presupposes that in specific situations bacteria cross the intestinal barrier, enter the systemic circulation, and cause a systemic inflammatory response syndrome. Critically ill children are at increased risk for bacterial translocation, particularly in the early postnatal age. Predisposing factors include intestinal obstruction, obstructive jaundice, intra-abdominal hypertension, intestinal ischemia/reperfusion injury and secondary ileus, and immaturity of the intestinal barrier per se. Despite good evidence from experimental studies to support the theory of bacterial translocation as a cause of sepsis, there is little evidence in human studies to confirm that translocation is directly correlated to bloodstream infections in critically ill children. This paper provides an overview of the gut microflora and its significance, a focus on the mechanisms employed by bacteria to gain access to the systemic circulation, and how critical illness creates a hostile environment in the gut and alters the microflora favoring the growth of pathogens that promote bacterial translocation. It also covers treatment with pre- and pro biotics during critical illness to restore the balance of microbial communities in a beneficial way with positive effects on intestinal permeability and bacterial translocation.

  10. Translocation of mercury and cadmium into the fruiting bodies of six higher fungi

    Energy Technology Data Exchange (ETDEWEB)

    Brunnert, H.; Zadrazil, F.

    1983-01-01

    The species- and metal-specific translocation of cadmium and mercury from the substrate to the fruiting bodies of 6 higher fungi has been investigated. The 6 species differed greatly in their ability to translocate cadmium and mercury. The highest translocation rates displayed Pleurotus flabellatus: 75.0% of the applied cadmium and 38.5% of the mercury could be recovered from the fruiting bodies. High translocation rates also found with Pleurotus ostreatus (19.3 and 38.5% for cadmium and mercury, respectively). This compares with only 1.27% of cadmium and 8.42% of mercury in Agaricus bisporus or 3.71% of cadmium and 3.63% of mercury in Pleurotus sajor caju. For Agaricus bisporus it was shown that there was proportionality of translocation over a 1:10 concentration range. In 4 out of 6 species there was a tendency towards higher heavy metal contents in later crops, when calculated on the basis of ..mu..g/g of dry fruiting body. In 4 out of 6 more mercury than cadmium was translocated into the fruiting bodies, the Cd/Hg ratios being 6.6, 2.0, 5.6, and 3.2, respectively. In Pleurotus sajor caju the ratio was about 1. Only in Pleurotus flabellatus more cadmium than mercury was found in the fruiting bodies (Cd/Hg ratio 0.65).

  11. The Impact of Variant Philadelphia Chromosome Translocations on the Clinical Course of Chronic Myeloid Leukemia.

    Science.gov (United States)

    Eyüpoğlu, Damla; Bozkurt, Süreyya; Haznedaroğlu, İbrahim; Büyükaşık, Yahya; Güven, Deniz

    2016-03-05

    Chronic myeloid leukemia (CML) is genetically characterized by the presence of the reciprocal translocation t(9;22) with the formation of Philadelphia (Ph) chromosome. Sometimes, the Ph translocation is generated by variant rearrangements. The prognostic impact of the variant translocations is still controversial. Among the 180 patients with Ph-positive CML who were treated in Hacettepe University Faculty of Medicine Division of Hematology, variant translocations were detected, and retrospectively clinical and prognostic features were described. Also we performed a comprehensive literature review on the prognosis of such variant cases before and after tyrosine kinase inhibitor era. Five patients (2.7%) had variant Ph chromosomes, involved in the rearrangements were chromosomes 2 (2 cases), 11, 14 and 15. Patients were treated with imatinib or dasatinib. All patients reached a stable major molecular response suggesting a prognosis not worse than standard translocation individuals. Our present data were compatible with the data of previous studies indicating no difference in the prognosis between standard and variant translocations in tyrosine kinase inhibitors era of CML.

  12. Copper speciation and isotopic fractionation in plants: uptake and translocation mechanisms.

    Science.gov (United States)

    Ryan, Brooke M; Kirby, Jason K; Degryse, Fien; Harris, Hugh; McLaughlin, Mike J; Scheiderich, Kathleen

    2013-07-01

    The fractionation of stable copper (Cu) isotopes during uptake into plant roots and translocation to shoots can provide information on Cu acquisition mechanisms. Isotope fractionation ((65) Cu/(63) Cu) and intact tissue speciation techniques (X-ray absorption spectroscopy, XAS) were used to examine the uptake, translocation and speciation of Cu in strategy I (tomato-Solanum lycopersicum) and strategy II (oat-Avena sativa) plant species. Plants were grown in controlled solution cultures, under varied iron (Fe) conditions, to test whether the stimulation of Fe-acquiring mechanisms can affect Cu uptake in plants. Isotopically light Cu was preferentially incorporated into tomatoes (Δ(65) Cu(whole plant-solution ) = c. -1‰), whereas oats showed minimal isotopic fractionation, with no effect of Fe supply in either species. The heavier isotope was preferentially translocated to shoots in tomato, whereas oat plants showed no significant fractionation during translocation. The majority of Cu in the roots and leaves of both species existed as sulfur-coordinated Cu(I) species resembling glutathione/cysteine-rich proteins. The presence of isotopically light Cu in tomatoes is attributed to a reductive uptake mechanism, and the isotopic shifts within various tissues are attributed to redox cycling during translocation. The lack of isotopic discrimination in oat plants suggests that Cu uptake and translocation are not redox selective.

  13. Prospects of detecting gravitational background radiation by Doppler tracking interplanetary spacecraft

    Energy Technology Data Exchange (ETDEWEB)

    Bertotti, B.; Carr, B.J.

    1980-03-15

    We examine the theoretical and experimental prospects of detecting a low-frequency, continuous, stochastic background of gravitational waves by Doppler tracking interplanetary spacecraft. From a theoretical standpoint, such a background may have been generated by various postgalactic processes or by pregalactic black hole formation; there could also exist a primordial background which goes back to the beginning of the universe. We review the characteristic frequency and density ranges which one might anticipate for these backgrounds. From an experimental standpoint, one's ability to detect a background is limited by the finite length of the record available and by an imperfect knowledge of the spectrum of various sources of noise. The fundamental contribution to the noise comes from the clock which regulates the frequency of the tracking waves. If one uses a hydrogen maser clock, this noise becomes progressively less important with decreasing frequency: one might hope to detect a critical density of background radiation at frequencies below 10/sup -2/ Hz and a background with 10/sup -4/ times the critical density at frequencies below 10/sup -5/ Hz. It is encouraging that some of the sorts of background which we anticipate from theoretical considerations fall within the observable regime. We discuss the extent to which other sources of noise may exceed the clock noise and the degree to which they can be eliminated.

  14. Background reionization history from omniscopes

    CERN Document Server

    Clesse, Sebastien; Ringeval, Christophe; Tashiro, Hiroyuki; Tytgat, Michel

    2012-01-01

    The measurements of the 21 cm brightness temperature fluctuations from the neutral hydrogen at the epoch of reionization (EoR) should inaugurate the next generation of cosmological observables. In this respect, many works have concentrated on the disambiguation of the cosmological signals from the dominant reionization foregrounds. However, even after perfect foregrounds removal, our ignorance on the background reionization history can significantly affect the cosmological parameter estimation. In particular, the interdependence between the hydrogen ionized fraction, the baryon density and the optical depth to the redshift of observation induce non-trivial degeneracies between the cosmological parameters that have not been considered so far. Using a simple, but consistent, reionization model, we revisit their expected constraints for a futuristic giant 21 cm omniscope by using for the first time Monte-Carlo-Markov-Chains (MCMC) methods on multi-redshift full sky simulated data. Our results agree well with the...

  15. Background illumination and automated perimetry.

    Science.gov (United States)

    Klewin, K M; Radius, R L

    1986-03-01

    Visual field function in the right and left eyes of 31 normal volunteers was evaluated with an automated projection perimeter (OCTOPUS). Serial visual field evaluations were repeated in these same eyes with neutral filters of increasing optical density. We compared the results of threshold determinations with the different neutral filters in place before the examined eye. Significant reduction in threshold sensitivity at several test spots throughout the central 30 degrees visual field was seen with neutral density filters of 0.5 log units or greater. The low level of background illumination of the OCTOPUS perimeter (4.0 apostilbs) may allow relatively minor reduction in light transmission by the ocular media to produce significant changes in the recorded level of threshold sensitivity during visual field evaluation.

  16. Polarization of Cosmic Microwave Background

    CERN Document Server

    Buzzelli, Alessandro; de Gasperis, Giancarlo; Vittorio, Nicola

    2016-01-01

    In this work we present an extension of the ROMA map-making code for data analysis of Cosmic Microwave Background polarization, with particular attention given to the inflationary polarization B-modes. The new algorithm takes into account a possible cross-correlated noise component among the different detectors of a CMB experiment. We tested the code on the observational data of the BOOMERanG (2003) experiment and we show that we are provided with a better estimate of the power spectra, in particular the error bars of the BB spectrum are smaller up to 20% for low multipoles. We point out the general validity of the new method. A possible future application is the LSPE balloon experiment, devoted to the observation of polarization at large angular scales.

  17. Bacillus cereus cytotoxins Hbl, Nhe and CytK are secreted via the Sec translocation pathway

    Directory of Open Access Journals (Sweden)

    Lindbäck Toril

    2010-11-01

    Full Text Available Abstract Background Bacillus cereus and the closely related Bacillus thuringiensis are Gram positive opportunistic pathogens that may cause food poisoning, and the three secreted pore-forming cytotoxins Hbl, Nhe and CytK have been implicated as the causative agents of diarrhoeal disease. It has been proposed that the Hbl toxin is secreted using the flagellar export apparatus (FEA despite the presence of Sec-type signal peptides. As protein secretion is of key importance in virulence of a microorganism, the mechanisms by which these toxins are secreted were further investigated. Results Sec-type signal peptides were identified in all toxin components, and secretion of Hbl component B was shown to be dependent on an intact Sec-type signal peptide sequence. Further indication that secretion of Hbl, Nhe and CytK is dependent on the Sec translocation pathway, the main pathway on which bacterial secretion relies, was suggested by the observed intracellular accumulation and reduced secretion of the toxins in cultures supplemented with the SecA inhibitor sodium azide. Although a FEA deficient strain (a flhA mutant showed reduced toxin expression and reduced cytotoxicity, it readily secreted overexpressed Hbl B, showing that the FEA is not required for Hbl secretion. Thus, the concurrent lack of flagella and reduced toxin secretion in the FEA deficient strain may point towards the presence of a regulatory link between motility and virulence genes, rather than FEA-dependent toxin secretion. Conclusions The Hbl, Nhe and CytK toxins appear to be secreted using the Sec pathway, and the reduced Hbl expression of a FEA deficient strain was shown not to be due to a secretion defect.

  18. Expression pattern of a nuclear encoded mitochondrial arginine-ornithine translocator gene from Arabidopsis

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    Schneider Anja

    2003-01-01

    Full Text Available Abstract Background Arginine and citrulline serve as nitrogen storage forms, but are also involved in biosynthetic and catabolic pathways. Metabolism of arginine, citrulline and ornithine is distributed between mitochondria and cytosol. For the shuttle of intermediates between cytosol and mitochondria transporters present on the inner mitochondrial membrane are required. Yeast contains a mitochondrial translocator for ornithine and arginine, Ort1p/Arg11p. Ort1p/Arg11p is a member of the mitochondrial carrier family (MCF essential for ornithine export from mitochondria. The yeast arg11 mutant, which is deficient in Ort1p/Arg11p grows poorly on media lacking arginine. Results High-level expression of a nuclear encoded Arabidopsis thaliana homolog (AtmBAC2 of Ort1p/Arg11p was able to suppress the growth deficiency of arg11. RT-PCR analysis demonstrated expression of AtmBAC2 in all tissues with highest levels in flowers. Promoter-GUS fusions showed preferential expression in flowers, i.e. pollen, in the vasculature of siliques and in aborted seeds. Variable expression was observed in leaf vasculature. Induction of the promoter was not observed during the first two weeks in seedlings grown on media containing NH4NO3, arginine or ornithine as sole nitrogen sources. Conclusion AtmBAC2 was isolated as a mitochondrial transporter for arginine in Arabidopsis. The absence of expression in developing seeds and in cotyledons of seedlings indicates that other transporters are responsible for storage and mobilization of arginine in seeds.

  19. Evaluation and re-evaluation of genetic radiation hazards in man. II. The arm number hypothesis and the induction of reciprocal translocations in man.

    Science.gov (United States)

    Sankaranarayanan, K

    1976-06-01

    The arm number hypothesis proposed by Brewen and collagues in 1973 has been examined in the light of information thus far available from mammalian studies. In experiments with peripheral blood lymphocytes (radiation in vitro), a linear relationship between dicentric yield and the effective chromosome arm number of the species was obtained in the mouse, Chinese hamster, goat, sheep, pig, wallaby and man. However, the data are not consistent with such a relationship in several primate species (marmoset, rhesus monkey, cynomolgus monkey, squirrel monkey and the slow loris), the cat and the dog. In the rabbit, the data are conflicting. In the mouse and Chinese hamster the frequencies of reciprocal translocations recorded in spermatocytes descended from irradiated spermatogonia are in line with the expectation based on the arm number hypothesis, whereas in the golden hamster, rabbit and the rhesus monkey they are not. In man and the marmoset, the limited data are not inconsistent with a 2-fold higher sensitivity of these species relative to the mouse although they do not rule out a difference as high as 4-fold. In the guinea-pig, the situation is unclear. New data on the transmission of reciprocal translocations in mice suggest that the frequency in the F1 progeny may be close to one-quarter of that recorded in the spermatocytes of the irradiated fathers (spermatogonial irradiation) at an exposure level of 150 R, whereas at higher exposures, the reduction factor is about one-eighth, the latter being in line with the earlier finding. All these results taken together suggest that inter-specific extrapolation from the radiosensitivity of somatic cells (to dicentric induction) to that of germ cells (to translocation induction) is fraught with uncertainity at present. Certain aspects that need to be studied in more detail in the context of induced chromosome aberrations are discussed.

  20. A translocator-specific export signal establishes the translocator-effector secretion hierarchy that is important for type III secretion system function.

    Science.gov (United States)

    Tomalka, Amanda G; Stopford, Charles M; Lee, Pei-Chung; Rietsch, Arne

    2012-12-01

    Type III secretion systems are used by many Gram-negative pathogens to directly deliver effector proteins into the cytoplasm of host cells. To accomplish this, bacteria secrete translocator proteins that form a pore in the host-cell membrane through which the effector proteins are then introduced into the host cell. Evidence from multiple systems indicates that the pore-forming translocator proteins are exported before effectors, but how this secretion hierarchy is established is unclear. Here we used the Pseudomonas aeruginosa translocator protein PopD as a model to identify its export signals. The N-terminal secretion signal and chaperone, PcrH, are required for export under all conditions. Two novel signals in PopD, one proximal to the chaperone binding site and one at the very C-terminus of the protein, are required for export of PopD before effector proteins. These novel export signals establish the translocator-effector secretion hierarchy, which in turn, is critical for the delivery of effectors into host cells.

  1. Bilateral renal agenesis/hypoplasia/dysplasia (BRAHD: postmortem analysis of 45 cases with breakpoint mapping of two de novo translocations.

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    Louise Harewood

    Full Text Available BACKGROUND: Bilateral renal agenesis/hypoplasia/dysplasia (BRAHD is a relatively common, lethal malformation in humans. Established clinical risk factors include maternal insulin dependent diabetes mellitus and male sex of the fetus. In the majority of cases, no specific etiology can be established, although teratogenic, syndromal and single gene causes can be assigned to some cases. METHODOLOGY/PRINCIPAL FINDINGS: 45 unrelated fetuses, stillbirths or infants with lethal BRAHD were ascertained through a single regional paediatric pathology service (male:female 34:11 or 3.1:1. The previously reported phenotypic overlaps with VACTERL, caudal dysgenesis, hemifacial microsomia and Müllerian defects were confirmed. A new finding is that 16/45 (35.6%; m:f 13:3 or 4.3:1 BRAHD cases had one or more extrarenal malformations indicative of a disoder of laterality determination including; incomplete lobulation of right lung (seven cases, malrotation of the gut (seven cases and persistence of the left superior vena cava (five cases. One such case with multiple laterality defects and sirelomelia was found to have a de novo apparently balanced reciprocal translocation 46,XY,t(2;6(p22.3;q12. Translocation breakpoint mapping was performed by interphase fluorescent in-situ hybridization (FISH using nuclei extracted from archival tissue sections in both this case and an isolated bilateral renal agenesis case associated with a de novo 46,XY,t(1;2(q41;p25.3. Both t(2;6 breakpoints mapped to gene-free regions with no strong evidence of cis-regulatory potential. Ten genes localized within 500 kb of the t(1;2 breakpoints. Wholemount in-situ expression analyses of the mouse orthologs of these genes in embryonic mouse kidneys showed strong expression of Esrrg, encoding a nuclear steroid hormone receptor. Immunohistochemical analysis showed that Esrrg was restricted to proximal ductal tissue within the embryonic kidney. CONCLUSIONS/SIGNIFICANCE: The previously unreported

  2. Fingerprints of Galactic Loop I on the Cosmic Microwave Background

    CERN Document Server

    Liu, Hao; Sarkar, Subir

    2014-01-01

    We investigate possible imprints of galactic foreground structures such as the `radio loops' in the derived maps of the cosmic microwave background. Surprisingly there is evidence for these not only at radio frequencies through their synchrotron radiation, but also at microwave frequencies where emission by dust dominates. This suggests the mechanism is magnetic dipole radiation from dust grains enriched by metallic iron, or ferrimagnetic molecules. This new foreground we have identified is present at high galactic latitudes, and potentially dominates over the expected B-mode polarisation signal due to primordial gravitational waves from inflation.

  3. Investigation of a background suppression transimpedance amplifier for photovoltaic detectors

    Science.gov (United States)

    Metzger, Ferdinand J., Jr.

    1992-12-01

    The current generation of transimpedance amplifier based detector systems are limited by opamp saturation when operating at a high gain or in the presence of a large background signal. To eliminate saturation, an amplifier that is frequency dependent is developed. Additionally, the noise sources in the conventional transimpedance amplifier and photovoltaic detector are quantified for comparison to any modified circuit. Initial results indicate that the frequency dependent detector system is a viable system, however, further development is required. Further research of this technology is expected to support future infrared and long range detection applications.

  4. Bim nuclear translocation and inactivation by viral interferon regulatory factor.

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    Young Bong Choi

    Full Text Available Viral replication efficiency is in large part governed by the ability of viruses to counteract pro-apoptotic signals induced by infection of the host cell. Human herpesvirus 8 (HHV-8 uses several strategies to block the host's innate antiviral defenses via interference with interferon and apoptotic signaling. Contributors include the four viral interferon regulatory factors (vIRFs 1-4, which function in dominant negative fashion to block cellular IRF activities in addition to targeting IRF signaling-induced proteins such as p53 and inhibiting other inducers of apoptosis such as TGFbeta receptor-activated Smad transcription factors. Here we identify direct targeting by vIRF-1 of BH3-only pro-apoptotic Bcl-2 family member Bim, a key negative regulator of HHV-8 replication, to effect its inactivation via nuclear translocation. vIRF-1-mediated relocalization of Bim was identified in transfected cells, by both immunofluorescence assay and western analysis of fractionated cell extracts. Also, co-localization of vIRF-1 and Bim was detected in nuclei of lytically infected endothelial cells. In vitro co-precipitation assays using purified vIRF-1 and Bim revealed direct interaction between the proteins, and Bim-binding residues of vIRF-1 were mapped by deletion and point mutagenesis. Generation and experimental utilization of Bim-refractory vIRF-1 variants revealed the importance of vIRF-1:Bim interaction, specifically, in pro-replication and anti-apoptotic activity of vIRF-1. Furthermore, blocking of the interaction with cell-permeable peptide corresponding to the Bim-binding region of vIRF-1 confirmed the relevance of vIRF-1:Bim association to vIRF-1 pro-replication activity. To our knowledge, this is the first report of an IRF protein that interacts with a Bcl-2 family member and of nuclear sequestration of Bim or any other member of the family as a means of inactivation. The data presented reveal a novel mechanism utilized by a virus to control

  5. Nodal diffuse large B-cell lymphomas in children and adolescents: immunohistochemical expression patterns and c-MYC translocation in relation to clinical outcome.

    Science.gov (United States)

    Gualco, Gabriela; Weiss, Lawrence M; Harrington, William J; Bacchi, Carlos E

    2009-12-01

    Diffuse large B-cell lymphoma (DLBCL) is a very infrequent neoplasm in the pediatric age group; therefore there are very few studies on the immunophenotype or genetics of these cases. We studied a series of 16 patients with nodal DLBCL occurring in patients between 10 and 18 years of age. The cases were classified according to the 2008 World Health Organization classification criteria, with application of immunohistochemistry for the detection of CD10, BCL-6, and MUM1 proteins to divide the lymphomas into germinal center and nongerminal center types. In addition, TCL1, BCL-2 expression, and the Ki-67 proliferation index were evaluated by immunohistochemistry, and c-MYC and BCL2 translocations were evaluated by fluorescence in situ hybridization. All these parameters were correlated with clinical features and outcome. Our study revealed that centroblastic morphology and the germinal center type of DLBCL are more prevalent in these young patients (63%), with 37% containing a c-MYC translocation. Only 1 case showed a BCL2 translocation, reflecting a double-hit case with features intermediate between DLBCL and Burkitt lymphoma. We found a higher frequency of BCL-2 expression than previously reported, with no direct influence on the outcome of the disease in univariate or multivariate analysis. The expression of TCL1 has not been specifically studied in nodal pediatric DLBCL before; we found a 31% incidence of TCL1 expression. MUM1 expression was observed in 44% of the cases and these positive cases showed a significant negative impact on clinical outcome. TCL1 is directly and significantly associated with the presence of c-MYC and a high proliferative index. The germinal center and nongerminal center subtypes showed significant differences for both overall survival and disease-free interval. c-MYC translocation was found in 37% of patients, and had a favorable impact on clinical outcome. We conclude that nodal pediatric and adolescent DLBCL are mainly of the germinal

  6. Planck 2013 results. XVIII. Gravitational lensing-infrared background correlation

    CERN Document Server

    Ade, P.A.R.; Armitage-Caplan, C.; Arnaud, M.; Ashdown, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Banday, A.J.; Barreiro, R.B.; Bartlett, J.G.; Basak, S.; Battaner, E.; Benabed, K.; Benoit, A.; Benoit-Levy, A.; Bernard, J.P.; Bersanelli, M.; Bethermin, M.; Bielewicz, P.; Bobin, J.; Bock, J.J.; Bonaldi, A.; Bond, J.R.; Borrill, J.; Bouchet, F.R.; Boulanger, F.; Bridges, M.; Bucher, M.; Burigana, C.; Butler, R.C.; Cardoso, J.F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chiang, L.Y.; Chiang, H.C.; Christensen, P.R.; Church, S.; Clements, D.L.; Colombi, S.; Colombo, L.P.L.; Couchot, F.; Coulais, A.; Crill, B.P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R.D.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Delouis, J.M.; Desert, F.X.; Diego, J.M.; Dole, H.; Donzelli, S.; Dore, O.; Douspis, M.; Dupac, X.; Efstathiou, G.; Ensslin, T.A.; Eriksen, H.K.; Finelli, F.; Forni, O.; Frailis, M.; Franceschi, E.; Galeotta, S.; Ganga, K.; Giard, M.; Giardino, G.; Giraud-Heraud, Y.; Gonzalez-Nuevo, J.; Gorski, K.M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J.E.; Hansen, F.K.; Hanson, D.; Harrison, D.; Henrot-Versille, S.; Hernandez-Monteagudo, C.; Herranz, D.; Hildebrandt, S.R.; Hivon, E.; Hobson, M.; Holmes, W.A.; Hornstrup, A.; Hovest, W.; Huffenberger, K.M.; Jaffe, T.R.; Jaffe, A.H.; Jones, W.C.; Juvela, M.; Keihanen, E.; Keskitalo, R.; Kisner, T.S.; Kneissl, R.; Knoche, J.; Knox, L.; Kunz, M.; Kurki-Suonio, H.; Lacasa, F.; Lagache, G.; Lahteenmaki, A.; Lamarre, J.M.; Lasenby, A.; Laureijs, R.J.; Lawrence, C.R.; Leonardi, R.; Leon-Tavares, J.; Lesgourgues, J.; Liguori, M.; Lilje, P.B.; Linden-Vornle, M.; Lopez-Caniego, M.; Lubin, P.M.; Macias-Perez, J.F.; Maffei, B.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D.J.; Martin, P.G.; Martinez-Gonzalez, E.; Masi, S.; Matarrese, S.; Matthai, F.; Mazzotta, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschenes, M.A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C.B.; Norgaard-Nielsen, H.U.; Noviello, F.; Novikov, D.; Novikov, I.; Osborne, S.; Oxborrow, C.A.; Paci, F.; Pagano, L.; Pajot, F.; Paoletti, D.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Poutanen, T.; Pratt, G.W.; Prezeau, G.; Prunet, S.; Puget, J.L.; Rachen, J.P.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Roudier, G.; Rowan-Robinson, M.; Rusholme, B.; Sandri, M.; Santos, D.; Savini, G.; Scott, D.; Seiffert, M.D.; Serra, P.; Shellard, E.P.S.; Spencer, L.D.; Starck, J.L.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sureau, F.; Sutton, D.; Suur-Uski, A.S.; Sygnet, J.F.; Tauber, J.A.; Tavagnacco, D.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Vittorio, N.; Wade, L.A.; Wandelt, B.D.; White, S.D.M.; Yvon, D.; Zacchei, A.; Zonca, A.

    2014-01-01

    The multi-frequency capability of the Planck satellite provides information both on the integrated history of star formation (via the cosmic infrared background, or CIB) and on the distribution of dark matter (via the lensing effect on the cosmic microwave background, or CMB). The conjunction of these two unique probes allows us to measure directly the connection between dark and luminous matter in the high redshift (1 1. We measure directly the SFR density with around 2 sigma significance for three redshift bins between z=1 and 7, thus opening a new window into the study of the formation of stars at early times.

  7. Chondromyxoid fibroma of rib with a novel chromosomal translocation: a report of four additional cases at unusual sites

    Directory of Open Access Journals (Sweden)

    Parwani Anil V

    2007-11-01

    Full Text Available Abstract Background Chondromyxoid fibromas (CMFs are rare benign chondroid/myxoid matrix-producing tumors that occur in metaphyses of long tubular bones, and very rarely in small bones of hands and feet. Flat bone involvement is even more uncommon. Prior cytogenetic analyses have identified complex abnormalities involving chromosome 6 in the majority of cases. Methods A search for CMF over an 8-year period (1999–2006 from the surgical pathology files of our institution yielded 16 cases. Four cases occurred in relatively unusual regions, three from the small bones of distal extremities and one from the rib. The rib lesion wassubmitted forroutinecytogenetic analysis. Results Radiographic studies revealed that all four lesions were well-defined expansile radiolucent lesions which expanded the bony cortices with lobulated margins, sclerotic rim, septation, and no calcification. Morphologically, all four lesions showed typical features of CMF and had low proliferative index with Ki-67. Cytogenetic analysis on the rib lesion revealed a novel chromosomal translocation, t(1;5(p13;p13. None of the four patients had a recurrence after a mean duration of follow-up of 24 months. Conclusion CMF originating in unusual locations should be distinguished from chondrosarcomas, especially on small biopsies, and should be included in the differential diagnosis. As previously noted in the literature, the cells can be positive for actin but unlike conventional chondroid neoplasms can be negative for S-100. To our knowledge, this is the first report describing a novel chromosomal translocation, t(1;5(p13;p13 in CMF.

  8. Chloroquine Increases Glucose Uptake via Enhancing GLUT4 Translocation and Fusion with the Plasma Membrane in L6 Cells

    Directory of Open Access Journals (Sweden)

    Qi Zhou

    2016-05-01

    Full Text Available Background/Aims: Chloroquine can induce an increase in the cellular uptake of glucose; however, the underlying mechanism is unclear. Methods: In this study, translocation of GLUT4 and intracellular Ca2+ changes were simultaneously observed by confocal microscope in L6 cells stably over-expressing IRAP-mOrange. The GLUT4 fusion with the plasma membrane (PM was traced using HA-GLUT4-GFP. Glucose uptake was measured using a cell-based glucose uptake assay. GLUT4 protein was detected by Western blotting and mRNA level was detected by RT-PCR. Results: We found that chloroquine induced significant increases in glucose uptake, glucose transporter GLUT4 translocation to the plasma membrane (GTPM, GLUT4 fusion with the PM, and intracellular Ca2+ in L6 muscle cells. Chloroquine-induced increases of GTPM and intracellular Ca2+ were inhibited by Gallein (Gβγ inhibitor and U73122 (PLC inhibitor. However, 2-APB (IP3R blocker only blocked the increase in intracellular Ca2+ but did not inhibit GTPM increase. These results indicate that chloroquine, via the Gβγ-PLC-IP3-IP3R pathway, induces elevation of Ca2+, and this Ca2+ increase does not play a role in chloroqui-ne-evoked GTPM increase. However, GLUT4 fusion with the PM and glucose uptake were significantly inhibited with BAPTA-AM. This suggests that Ca2+ enhances GLUT4 fusion with the PM resulting in glucose uptake increase. Conclusion: Our data indicate that chloroquine via Gβγ-PLC-IP3-IP3R induces Ca2+ elevation, which in turn promotes GLUT4 fusion with the PM. Moreover, chloroquine can enhance GLUT4 trafficking to the PM. These mechanisms eventually result in glucose uptake increase in control and insulin-resistant L6 cells. These findings suggest that chloroquine might be a potential drug for improving insulin tolerance in diabetic patients.

  9. Neurobiological background of negative symptoms.

    Science.gov (United States)

    Galderisi, Silvana; Merlotti, Eleonora; Mucci, Armida

    2015-10-01

    Studies investigating neurobiological bases of negative symptoms of schizophrenia failed to provide consistent findings, possibly due to the heterogeneity of this psychopathological construct. We tried to review the findings published to date investigating neurobiological abnormalities after reducing the heterogeneity of the negative symptoms construct. The literature in electronic databases as well as citations and major articles are reviewed with respect to the phenomenology, pathology, genetics and neurobiology of schizophrenia. We searched PubMed with the keywords "negative symptoms," "deficit schizophrenia," "persistent negative symptoms," "neurotransmissions," "neuroimaging" and "genetic." Additional articles were identified by manually checking the reference lists of the relevant publications. Publications in English were considered, and unpublished studies, conference abstracts and poster presentations were not included. Structural and functional imaging studies addressed the issue of neurobiological background of negative symptoms from several perspectives (considering them as a unitary construct, focusing on primary and/or persistent negative symptoms and, more recently, clustering them into factors), but produced discrepant findings. The examined studies provided evidence suggesting that even primary and persistent negative symptoms include different psychopathological constructs, probably reflecting the dysfunction of different neurobiological substrates. Furthermore, they suggest that complex alterations in multiple neurotransmitter systems and genetic variants might influence the expression of negative symptoms in schizophrenia. On the whole, the reviewed findings, representing the distillation of a large body of disparate data, suggest that further deconstruction of negative symptomatology into more elementary components is needed to gain insight into underlying neurobiological mechanisms.

  10. Frequency noise in frequency swept fiber laser.

    Science.gov (United States)

    Pedersen, Anders Tegtmeier; Rottwitt, Karsten

    2013-04-01

    This Letter presents a measurement of the spectral content of frequency shifted pulses generated by a lightwave synthesized frequency sweeper. We found that each pulse is shifted in frequency with very high accuracy. We also discovered that noise originating from light leaking through the acousto- optical modulators and forward propagating Brillouin scattering appear in the spectrum.

  11. Frequency noise in frequency swept fiber laser

    DEFF Research Database (Denmark)

    Pedersen, Anders Tegtmeier; Rottwitt, Karsten

    2013-01-01

    This Letter presents a measurement of the spectral content of frequency shifted pulses generated by a lightwave synthesized frequency sweeper. We found that each pulse is shifted in frequency with very high accuracy. We also discovered that noise originating from light leaking through the acousto...

  12. Frequency selectivity at very low centre frequencies

    DEFF Research Database (Denmark)

    Orellana, Carlos Andrés Jurado; Pedersen, Christian Sejer; Marquardt, Torsten

    2010-01-01

    -3638 (2007)]. Recent experiments showed that the exact frequency varies from individual to individual. Besides, the helicotrema region in the METF has been found to highly influence frequency selectivity for centre frequencies (CFs) below 80 Hz (Jurado and Moore in prep). By using individual METF...

  13. Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions.

    Science.gov (United States)

    Wolters, Manuel; Zobiak, Bernd; Nauth, Theresa; Aepfelbacher, Martin

    2015-10-13

    Many gram-negative bacteria including pathogenic Yersinia spp. employ type III secretion systems to translocate effector proteins into eukaryotic target cells. Inside the host cell the effector proteins manipulate cellular functions to the benefit of the bacteria. To better understand the control of type III secretion during host cell interaction, sensitive and accurate assays to measure translocation are required. We here describe the application of an assay based on the fusion of a Yersinia enterocolitica effector protein fragment (Yersinia outer protein; YopE) with TEM-1 beta-lactamase for quantitative analysis of translocation. The assay relies on cleavage of a cell permeant FRET dye (CCF4/AM) by translocated beta-lactamase fusion. After cleavage of the cephalosporin core of CCF4 by the beta-lactamase, FRET from coumarin to fluorescein is disrupted and excitation of the coumarin moiety leads to blue fluorescence emission. Different applications of this method have been described in the literature highlighting its versatility. The method allows for analysis of translocation in vitro and also in in vivo, e.g., in a mouse model. Detection of the fluorescence signals can be performed using plate readers, FACS analysis or fluorescence microscopy. In the setup described here, in vitro translocation of effector fusions into HeLa cells by different Yersinia mutants is monitored by laser scanning microscopy. Recording intracellular conversion of the FRET reporter by the beta-lactamase effector fusion in real-time provides robust quantitative results. We here show exemplary data, demonstrating increased translocation by a Y. enterocolitica YopE mutant compared to the wild type strain.

  14. Clonal diversification of primary BALB/c plasmacytomas harboring T(12;15) chromosomal translocations.

    Science.gov (United States)

    Kovalchuk, A L; Mushinski, E B; Janz, S

    2000-05-01

    DNA sequence analysis of PCR amplified Igh/c-myc junction fragments of T(12;15) chromosome translocations and immunohistochemical determination of immunoglobulin isotype production were employed to study the clonal diversification of neoplastic translocated plasma cells that resided in peritoneal inflammatory granulomas of BALB/c mice harboring primary plasmacytomas. The diversity of plasma cells was found to take two major forms when the fine structure of the T(12;15) translocation was used as the clonotypic marker. First, mosaics of clones containing translocations that were apparently unrelated to each other were detected in nine out of 17 (53%) mice. Second, subclones derived from common T(12;15)+ progenitors by either secondary deletions in translocation breakpoint regions or aberrant isotype switching near translocation breaksites were found in five of 17 (29.5%) mice. When Ig expression was utilized as the clonotypic marker, clonal mosaics were shown to occur in all mice. This was demonstrated by the finding that the prevalent IgA- or IgG-producing plasmacytoma clone was invariably accompanied by smaller clones of IgG- or IgA-expressing neoplastic plasma cells, respectively. These results provided new insights into the clonal diversification at the terminal stage of plasmacytomagenesis. In addition, they suggested that BALB/c plasmacytomas may be uniquely useful for studying clonal diversity during B cell oncogenesis, since clonal evolution can be evaluated in a pool of tumor and tumor precursor cells that is clearly defined by the T(12;15) chromosomal translocation and the production of monoclonal immunoglobulin.

  15. Driven polymer translocation in good and bad solvent: Effects of hydrodynamics and tension propagation.

    Science.gov (United States)

    Moisio, J E; Piili, J; Linna, R P

    2016-08-01

    We investigate the driven polymer translocation through a nanometer-scale pore in the presence and absence of hydrodynamics both in good and bad solvent. We present our results on tension propagating along the polymer segment on the cis side that is measured for the first time using our method that works also in the presence of hydrodynamics. For simulations we use stochastic rotation dynamics, also called multiparticle collision dynamics. We find that in the good solvent the tension propagates very similarly whether hydrodynamics is included or not. Only the tensed segment is by a constant factor shorter in the presence of hydrodynamics. The shorter tensed segment and the hydrodynamic interactions contribute to a smaller friction for the translocating polymer when hydrodynamics is included, which shows as smaller waiting times and a smaller exponent in the scaling of the translocation time with the polymer length. In the bad solvent hydrodynamics has a minimal effect on polymer translocation, in contrast to the good solvent, where it speeds up translocation. We find that under bad-solvent conditions tension does not spread appreciably along the polymer. Consequently, translocation time does not scale with the polymer length. By measuring the effective friction in a setup where a polymer in free solvent is pulled by a constant force at the end, we find that hydrodynamics does speed up collective polymer motion in the bad solvent even more effectively than in the good solvent. However, hydrodynamics has a negligible effect on the motion of individual monomers within the highly correlated globular conformation on the cis side and hence on the entire driven translocation under bad-solvent conditions.

  16. A comparative study on the uptake and translocation of organochlorines by Phragmites australis

    Energy Technology Data Exchange (ETDEWEB)

    San Miguel, Angélique; Ravanel, Patrick [Laboratoire d’Ecologie Alpine, UMR CNRS n°5553, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 09 (France); Raveton, Muriel, E-mail: muriel.raveton@ujf-grenoble.fr [Laboratoire d’Ecologie Alpine, UMR CNRS n°5553, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 09 (France)

    2013-01-15

    Highlights: ► This study compares uptake/translocation of organochlorine congeners in macrophytes. ► First, root OC uptake was strongly linked with the partitioning/diffusion process. ► With time exposure, bioconcentration increased with OC solubility and volatility. ► Translocation was linked to the combination of water flow and vapor flux transfers. ► The most volatile OCs might be phytovolatilized from foliar surfaces. -- Abstract: Organochlorines (OCs) are persistent chemicals found in various environmental compartments. The differences in the uptake of {sup 14}C-labeled 1,4-dichlorobenzene (DCB), 1,2,4-trichlorobenzene (TCB) and γ-hexachlorocyclohexane (γHCH) by Phragmites australis were investigated under hydroponic conditions. The first step in sorption appears to be correlated with the hydrophobic nature of the compounds, since log-linear correlations were obtained between root concentration factor and partition coefficient (LogK{sub ow}). After 7 days of exposure, plant uptake of DCB, TCB, γHCH was significant with bioconcentration factors reaching 14, 19 and 15, respectively. Afterwards, uptake and translocation were seen to be more complex, with a loss of the simple relationship between uptake and LogK{sub ow}. Linear correlations between the bioconcentration/translocation factors and the physico-chemical properties of OCs were shown, demonstrating that translocation from roots to shoots increases with solubility and volatility of the OCs. This suggests that OC-translocation inside plants might result from the combination of two processes, xylem sap flow and vapor fluxes. {sup 14}C-phytovolatilization was measured and was correlated with the volatility of the compounds; the more volatile OCs being most the likely to be phytovolatilized from foliar surfaces (p = 0.0008). Thus, OC-uptake/translocation appears to proceed at a rate that depends mostly on the OCs hydrophobicity, solubility and volatility.

  17. Cosmic Microwave Background Temperature at Galaxy Clusters

    CERN Document Server

    Battistelli, E S; Lamagna, L; Melchiorri, F; Palladino, E; Savini, G; Cooray, A R; Melchiorri, A; Rephaeli, Y; Shimon, M

    2002-01-01

    We have deduced the cosmic microwave background (CMB) temperature in the Coma cluster (Abell 1656, z=0.0231), and in Abell 2163 (z=0.203) from spectral measurements of the Sunyaev-Zel'dovich (SZ) effect over four passbands at radio and microwave frequencies. The resulting temperatures at these redshifts are T_{Coma} = 2.750^{+0.043}_{-0.032} K and T_{A2163} = 3.335^{+0.065}_{-0.066} K, respectively. These values are in good agreement with the basic relation T(z)=T_{0}(1+z), where T_{0} = (2.725 +/- 0.002) K as measured by the COBE/FIRAS experiment. Alternative scaling relations that are conjectured in non-standard cosmologies can be constrained by the data; for example, if T(z) = T_{0}(1+z)^{1-a} or T(z)=T_0[1+(1+d)z], then a=-0.07^{+0.12}_{-0.11} and d = 0.07 +/- 0.12. We briefly discuss future prospects for more precise SZ measurements of T(z) at higher redshifts.

  18. Soluble plantain fibre blocks adhesion and M-cell translocation of intestinal pathogens.

    Science.gov (United States)

    Roberts, Carol L; Keita, Asa V; Parsons, Bryony N; Prorok-Hamon, Maelle; Knight, Paul; Winstanley, Craig; O' Kennedy, Niamh; Söderholm, Johan D; Rhodes, Jonathan M; Campbell, Barry J

    2013-01-01

    Dietary fibres may have prebiotic effects mediated by promotion of beneficial bacteria. This study explores the possibility that soluble plant fibre may also improve health by inhibiting epithelial adhesion and translocation by pathogenic bacteria. We have focussed on soluble non-starch polysaccharide (NSP) from plantain bananas (Musa spp.) which previous studies showed to be particularly effective at blocking Escherichia coli epithelial adherence. In vitro and ex vivo studies assessed the ability of plantain NSP to inhibit epithelial cell adhesion and invasion of various bacterial pathogens, and to inhibit their translocation through microfold (M)-cells and human Peyer's patches mounted in Ussing chambers. Plantain NSP showed dose-related inhibition of epithelial adhesion and M-cell translocation by a range of pathogens. At 5mg/ml, a concentration readily achievable in the gut lumen, plantain NSP inhibited adhesion to Caco2 cells by Salmonella Typhimurium (85.0 ± 8.2%, PPlantain NSP also inhibited invasion of Caco2 cells by S. Typhimurium (80.2 ± 9.7%) and Sh. sonnei (46.7 ± 13.4%); PPlantain NSP, 5mg/ml, also inhibited translocation of S. Typhimurium and Sh. sonnei across M-cells by 73.3 ± 5.2% and 46.4 ± 7.7% respectively (Pplantain NSP (Pplantain fibre can block epithelial adhesion and M-cell translocation of intestinal pathogens. This represents an important novel mechanism by which soluble dietary fibres can promote intestinal health and prevent infective diarrhoea.

  19. Jumping translocation involving 11q13 in a patient with primitive neuroectodermal tumor (PNET)

    Energy Technology Data Exchange (ETDEWEB)

    Nemana, L.; Fung, I.; Sun, G. [Alfigen/The Genetics Institute, Pasadena, CA (United States)] [and others

    1994-09-01

    Multiple translocations between a donor chromosome at a common breakpoint site with different recipient chromosomes (jumping translocation) have been rarely described in the same patient with hematological malignancies. Here we present a case of a two-year-old male with therapy-related acute non-lymphocytic leukemia (t-ANLL) secondary to treatment of PNET of mandible. The initial chromosome analysis revealed clonal hyperdiploidy with a mainline of 47,XY,+11. Follow-up study revealed no hyperdiploidy, a partial deletion of 7q22 to 7q36 (in four cells), as well as a jumping translocation between 11q13 and seven different chromosomes in seven different cells. The recipient chromosomes and their breakpoints were 4q35, 5p15.3, 11q13, 13q23, 14q32, 17p13 and 20q13.3. Multiple chromosomal rearrangements are usually associated with a poor prognosis. However, the significance of different translocations involving the same donor chromosome with a constant breakpoint in this patient is not determined. It has been proposed that the sites of recurrent translocations or fragile sites may harbor or be in close proximity to proto-oncogenes. Molecular studies are required to elucidate the relationship between these breakpoints and the disease progression in our patient.

  20. Detection of a complex translocation using fluorescent in situ hybridization (FISH)

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, B.A. [Brandeis Univ., Waltham, MA (United States); Abuelo, D.N. [Rhode Island Hospital, Providence, RI (United States); Mark, H.F. [Brown Univ. School of Medicine, Providence, RI (United States)

    1994-09-01

    The use of fluorescent in situ hybridization (FISH) allowed the detection of a complex 3-way translocation in a patient with multiple congenital malformations and mental retardation. The patient was a 10-year-old girl with mental retardation, seizures, repaired cleft palate, esotropia, epicanthal folds, broad nasal bridge, upward slanting palpebral fissures, single transverse palmar crease, brachydactyly, hypoplastic nails, ectrodactyly between the third and fourth right toes, and hypoplasia of the left third toe. Chromosome analysis performed at birth was reported as normal. We performed high resolution banding analysis which revealed an apparently balanced translocation between chromosomes 2 and 9. However, because of her multiple abnormalities, further studies were ordered. Fluorescent in situ hybridization (FISH) using chromosome painting probes revealed a karyotype of 46,XX,t(2;8;9) (2pter{yields}q31::8q21.2{yields}8qter; 8pter{yields}q21.2::2q31{yields}q34::9q34{yields}qter; 9pter{yields}q34::2q34{yields}qter). The 3-way translocation appears to be de novo, as neither parent is a translocation carrier. This case illustrates the importance of using FISH to further investigate cases of apparently balanced translocations in the presence of phenotypic abnormalities and/or mental retardation.

  1. The impact of conservation-driven translocations on blood parasite prevalence in the Seychelles warbler

    Science.gov (United States)

    Fairfield, Eleanor A.; Hutchings, Kimberly; Gilroy, Danielle L.; Kingma, Sjouke A.; Burke, Terry; Komdeur, Jan; Richardson, David S.

    2016-01-01

    Introduced populations often lose the parasites they carried in their native range, but little is known about which processes may cause parasite loss during host movement. Conservation-driven translocations could provide an opportunity to identify the mechanisms involved. Using 3,888 blood samples collected over 22 years, we investigated parasite prevalence in populations of Seychelles warblers (Acrocephalus sechellensis) after individuals were translocated from Cousin Island to four new islands (Aride, Cousine, Denis and Frégate). Only a single parasite (Haemoproteus nucleocondensus) was detected on Cousin (prevalence = 52%). This parasite persisted on Cousine (prevalence = 41%), but no infection was found in individuals hatched on Aride, Denis or Frégate. It is not known whether the parasite ever arrived on Aride, but it has not been detected there despite 20 years of post-translocation sampling. We confirmed that individuals translocated to Denis and Frégate were infected, with initial prevalence similar to Cousin. Over time, prevalence decreased on Denis and Frégate until the parasite was not found on Denis two years after translocation, and was approaching zero prevalence on Frégate. The loss (Denis) or decline (Frégate) of H. nucleocondensus, despite successful establishment of infected hosts, must be due to factors affecting parasite transmission on these islands. PMID:27405249

  2. Autism Spectrum Disorder in a Girl with a De Novo X;19 Balanced Translocation

    Directory of Open Access Journals (Sweden)

    Marcelo Razera Baruffi

    2012-01-01

    Full Text Available Balanced X-autosome translocations are rare, and female carriers are a clinically heterogeneous group of patients, with phenotypically normal women, history of recurrent miscarriage, gonadal dysfunction, X-linked disorders or congenital abnormalities, and/or developmental delay. We investigated a patient with a de novo X;19 translocation. The six-year-old girl has been evaluated due to hyperactivity, social interaction impairment, stereotypic and repetitive use of language with echolalia, failure to follow parents/caretakers orders, inconsolable outbursts, and persistent preoccupation with parts of objects. The girl has normal cognitive function. Her measurements are within normal range, and no other abnormalities were found during physical, neurological, or dysmorphological examinations. Conventional cytogenetic analysis showed a de novo balanced translocation, with the karyotype 46,X,t(X;19(p21.2;q13.4. Replication banding showed a clear preference for inactivation of the normal X chromosome. The translocation was confirmed by FISH and Spectral Karyotyping (SKY. Although abnormal phenotypes associated with de novo balanced chromosomal rearrangements may be the result of disruption of a gene at one of the breakpoints, submicroscopic deletion or duplication, or a position effect, X; autosomal translocations are associated with additional unique risk factors including X-linked disorders, functional autosomal monosomy, or functional X chromosome disomy resulting from the complex X-inactivation process.

  3. Rad51 inhibits translocation formation by non-conservative homologous recombination in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Glenn M Manthey

    Full Text Available Chromosomal translocations are a primary biological response to ionizing radiation (IR exposure, and are likely to result from the inappropriate repair of the DNA double-strand breaks (DSBs that are created. An abundance of repetitive sequences in eukaryotic genomes provides ample opportunity for such breaks to be repaired by homologous recombination (HR between non-allelic repeats. Interestingly, in the budding yeast, Saccharomyces cerevisiae the central strand exchange protein, Rad51 that is required for DSB repair by gene conversion between unlinked repeats that conserves genomic structure also suppresses translocation formation by several HR mechanisms. In particular, Rad51 suppresses translocation formation by single-strand annealing (SSA, perhaps the most efficient mechanism for translocation formation by HR in both yeast and mammalian cells. Further, the enhanced translocation formation that emerges in the absence of Rad51 displays a distinct pattern of genetic control, suggesting that this occurs by a separate mechanism. Since hypomorphic mutations in RAD51 in mammalian cells also reduce DSB repair by conservative gene conversion and stimulate non-conservative repair by SSA, this mechanism may also operate in humans and, perhaps contribute to the genome instability that propels the development of cancer.

  4. Translocation domain mutations affecting cellular toxicity identify the Clostridium difficile toxin B pore.

    Science.gov (United States)

    Zhang, Zhifen; Park, Minyoung; Tam, John; Auger, Anick; Beilhartz, Greg L; Lacy, D Borden; Melnyk, Roman A

    2014-03-11

    Disease associated with Clostridium difficile infection is caused by the actions of the homologous toxins TcdA and TcdB on colonic epithelial cells. Binding to target cells triggers toxin internalization into acidified vesicles, whereupon cryptic segments from within the 1,050-aa translocation domain unfurl and insert into the bounding membrane, creating a transmembrane passageway to the cytosol. Our current understanding of the mechanisms underlying pore formation and the subsequent translocation of the upstream cytotoxic domain to the cytosol is limited by the lack of information available regarding the identity and architecture of the transmembrane pore. Here, through systematic perturbation of conserved sites within predicted membrane-insertion elements of the translocation domain, we uncovered highly sensitive residues--clustered between amino acids 1,035 and 1,107--that when individually mutated, reduced cellular toxicity by as much as >1,000-fold. We demonstrate that defective variants are defined by impaired pore formation in planar lipid bilayers and biological membranes, resulting in an inability to intoxicate cells through either apoptotic or necrotic pathways. These findings along with the unexpected similarities uncovered between the pore-forming "hotspots" of TcdB and the well-characterized α-helical diphtheria toxin translocation domain provide insights into the structure and mechanism of formation of the translocation pore for this important class of pathogenic toxins.

  5. Cardiolipin is essential for higher proton translocation activity of reconstituted Fo

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Fo membrane domain of FoF1-ATPase complex had been purifiedfrom porcine heart mitochondria. SDS-PAGE with silver staining indicated that the purity of Fo was about 85% and the sample contained no subunits of F1-ATPase. The purified Fo was reconstituted into liposomes with different phospholipid composition, and the effect of CL (cardiolipin), PA (phosphatidic acid), PI (phosphatidylinositol) and PS (phosphatidylserine) on the H+ translocation activity of Fo was investigated. The results demonstrated that CL, PA and PI could promote the proton translocation of Fo with the order of CL>PA>>PI, while PS inhibited it. Meanwhile ADM (adriamycin) severely impaired the proton translocation activity of Fo vesicles containing CL, which suggested that CL's stimulation of the activity of reconstituted Fo might correlate with its non-bilayer propensity. After Fo was incorporated into the liposomes containing PE (phosphatidylethanolamine), DOPE (dioleoylphosphatidylethanolamine) as well as DEPE (dielaidoylphosphatidylethanolamine), it was found that the proton translocation activity of Fo vesicles increased with the increasing content of PE or DOPE, which has high propensity of forming non-bilayer structure, but was independent of DEPE. The dynamic quenching of the intrinsic fluorescence of tryptophan by HB (hypocrellin B) as well as fluorescent spectrum of acrylodan labeling Fo at cysteine indicated that CL could induce Fo to a suitable conformation resulting in higher proton translocation activity.

  6. Chaperone driven polymer translocation through Nanopore: spatial distribution and binding energy

    CERN Document Server

    Abdolvahab, Rouhollah Haji

    2016-01-01

    Chaperones are binding proteins which work as a driving force to bias the biopolymer translocation by binding to it near the pore and preventing its backsliding. Chaperones may have different spatial distribution. Recently we show the importance of their spatial distribution in translocation and how it effects on sequence dependency of the translocation time. Here we focus on homopolymers and exponential distribution. As a result of the exponential distribution of chaperones, energy dependency of the translocation time will changed and one see a minimum in translocation time versus effective energy curve. The same trend can be seen in scaling exponent of time versus polymer length, $\\beta$ ($T\\sim\\beta$). Interestingly in some special cases e.g. chaperones of size $\\lambda=6$ and with exponential distribution rate of $\\alpha=5$, the minimum reaches even to amount of less than $1$ ($\\beta<1$). We explain the possibility of this rare result and base on a theoretical discussion we show that by taking into acc...

  7. Spatially explicit decision support for selecting translocation areas for Mojave desert tortoises

    Science.gov (United States)

    Heaton, Jill S.; Nussear, Kenneth E.; Esque, Todd C.; Inman, Richard D.; Davenport, Frank; Leuteritz, Thomas E.; Medica, Philip A.; Strout, Nathan W.; Burgess, Paul A.; Benvenuti, Lisa

    2008-01-01

    Spatially explicit decision support systems are assuming an increasing role in natural resource and conservation management. In order for these systems to be successful, however, they must address real-world management problems with input from both the scientific and management communities. The National Training Center at Fort Irwin, California, has expanded its training area, encroaching U.S. Fish and Wildlife Service critical habitat set aside for the Mojave desert tortoise (Gopherus agassizii), a federally threatened species. Of all the mitigation measures proposed to offset expansion, the most challenging to implement was the selection of areas most feasible for tortoise translocation. We developed an objective, open, scientifically defensible spatially explicit decision support system to evaluate translocation potential within the Western Mojave Recovery Unit for tortoise populations under imminent threat from military expansion. Using up to a total of 10 biological, anthropogenic, and/or logistical criteria, seven alternative translocation scenarios were developed. The final translocation model was a consensus model between the seven scenarios. Within the final model, six potential translocation areas were identified.

  8. DNA Translocation through Nanopores at Physiological Ionic Strengths Requires Precise Nanoscale Engineering.

    Science.gov (United States)

    Franceschini, Lorenzo; Brouns, Tine; Willems, Kherim; Carlon, Enrico; Maglia, Giovanni

    2016-09-27

    Many important processes in biology involve the translocation of a biopolymer through a nanometer-scale pore. Moreover, the electrophoretic transport of DNA across nanopores is under intense investigation for single-molecule DNA sequencing and analysis. Here, we show that the precise patterning of the ClyA biological nanopore with positive charges is crucial to observe the electrophoretic translocation of DNA at physiological ionic strength. Surprisingly, the strongly electronegative 3.3 nm internal constriction of the nanopore did not require modifications. Further, DNA translocation could only be observed from the wide entry of the nanopore. Our results suggest that the engineered positive charges are important to align the DNA in order to overcome the entropic and electrostatic barriers for DNA translocation through the narrow constriction. Finally, the dependencies of nucleic acid translocations on the Debye length of the solution are consistent with a physical model where the capture of double-stranded DNA is diffusion-limited while the capture of single-stranded DNA is reaction-limited.

  9. Virus DNA translocation: progress towards a first ascent of mount pretty difficult.

    Science.gov (United States)

    Maluf, Nasib K; Feiss, Michael

    2006-07-01

    Virion DNA molecules of large dsDNA viruses are highly condensed. To pack the DNA, an ATP hydrolysis-powered motor translocates the DNA into a preformed empty protein shell, the prohead. The icosahedral prohead has a special fivefold vertex, the portal vertex, where the translocation machinery acts. The portal vertex contains the portal protein, a gear-shaped dodecamer of radially disposed subunits with a central channel for DNA entry. The symmetry mismatch between the fivefold symmetry of the shell vertex and the 12-fold symmetry of the portal protein has prompted DNA packaging models in which ATP-driven portal protein rotation drives DNA translocation. In this issue of Molecular Microbiology, Baumann and colleagues test portal rotation models using bacteriophage T4. A fusion between the gp20 portal protein and the HOC external shell decoration protein is used to create a block to portal rotation. Finding that DNA packaging is unimpeded in proheads containing the fusion argues that portal rotation is not crucial to DNA translocation. The paper is a landmark for describing direct testing of the mechanism of DNA translocation.

  10. All-Atom Molecular Dynamics Simulation of Protein Translocation through an α-Hemolysin Nanopore

    KAUST Repository

    Di Marino, Daniele

    2015-08-06

    © 2015 American Chemical Society. Nanopore sensing is attracting the attention of a large and varied scientific community. One of the main issues in nanopore sensing is how to associate the measured current signals to specific features of the molecule under investigation. This is particularly relevant when the translocating molecule is a protein and the pore is sufficiently narrow to necessarily involve unfolding of the translocating protein. Recent experimental results characterized the cotranslocational unfolding of Thioredoxin (Trx) passing through an α-hemolisin pore, providing evidence for the existence of a multistep process. In this study we report the results of all-atom molecular dynamics simulations of the same system. Our data indicate that Trx translocation involves two main barriers. The first one is an unfolding barrier associated with a translocation intermediate where the N-terminal region of Trx is stuck at the pore entrance in a conformation that strongly resembles the native one. After the abrupt unfolding of the N-terminal region, the Trx enters the α-hemolisin vestibule. During this stage, the constriction is occupied not only by the translocating residue but also by a hairpin-like structure forming a tangle in the constriction. The second barrier is associated with the disentangling of this region.

  11. 主要农作物转基因飘流频率和距离的数据调研与分析Ⅰ.背景、调研目的及所考虑的问题%Data Survey and Analysis of the Tansgene Flow Frequencies and Distances in Major Crops Ⅰ .The Background, Aim and General Consideration

    Institute of Scientific and Technical Information of China (English)

    王志兴; 王旭静; 贾士荣

    2011-01-01

    Transgene flow's potential risk on environment and food is one of the hot spots that major public concerned.The data and information on tansgene flow in major corps published internationally until 2010 have been surveyed and analyzed.The distances of transgene flow at certain threshold level for different major crops are particularly defined.In this article, the background, aim and general consideration for this survey were discussed.On the scientific basis,the principle of classification management and threshold management are proposed to control the risk of transgene flow.%转基因飘流及其可能引起的环境和食品潜在风险是公众关注的热点之一.对2010年前主要农作物转基因飘流的数据和信息进行了调研与分析,特别是对一定允许阈值下的基因飘流距离进行了归纳.在分别报道各种作物的基因飘流数据前,对调研的背景、目的及所考虑的问题进行了讨论,基于科学分析,建议采用分类管理和阈值管理的原则来控制转基因飘流的风险.

  12. Translocation of chicken heart apocytochrome c and its mutants (C17S, H18D) across mitochondrial membrane

    Institute of Scientific and Technical Information of China (English)

    朱勇; 韩学海; 杨福愉

    1999-01-01

    Cytochrome c is a component of mitochondrial respiratory chain, located at the outer side of mitochondrial inner membrane. Its precursor, apocytochrome c, is encoded by a nuclear gene, synthesized on cytoplasmic ribosomes, and posttranslationally imported into mitochondria, but apocytochrome c is unique in the translocation compared with most mitochondrial proteins. It does not carry a cleavable amino terminal targeting sequence; no proteinous receptor on the mitochondrial outer membrane is identified for its import and its translocation does not compete with other preproteins for translocation machinery in the outer membrane. Besides, neither ATP nor membrane potential is required for its translocation across mitochonctria.

  13. Cosmic Microwave Background Science at Commercial Airline Altitudes

    CERN Document Server

    Feeney, Stephen M; Peiris, Hiranya V; Verde, Licia; Errard, Josquin

    2016-01-01

    Obtaining high-sensitivity measurements of degree-scale cosmic microwave background (CMB) polarization is the most direct path to detecting primordial gravitational waves. Robustly recovering any primordial signal from the dominant foreground emission will require high-fidelity observations at multiple frequencies, with excellent control of systematics. We explore the potential for a new platform for CMB observations, the Airlander 10 hybrid air vehicle, to perform this task. We show that the Airlander 10 platform, operating at commercial airline altitudes, is well-suited to mapping frequencies above 220 GHz, which are critical for cleaning CMB maps of dust emission. Optimizing the distribution of detectors across frequencies, we forecast the ability of Airlander 10 to clean foregrounds of varying complexity as a function of altitude, demonstrating its complementarity with both existing (Planck) and ongoing (C-BASS) foreground observations. This novel platform could play a key role in defining our ultimate vi...

  14. The Anisotropy of the Microwave Background to l = 3500 Mosaic Observations with the Cosmic Background Imager

    CERN Document Server

    Pearson, T J; Readhead, A C S; Shepherd, M C; Sievers, J L; Udomprasert, P S; Cartwright, J K; Farmer, A J; Padin, S; Myers, S T; Bond, J R; Contaldi, C R; Pen, U L; Prunet, S; Pogosyan, D; Carlstrom, J E; Kovács, J; Leitch, E M; Pryke, C L; Halverson, N W; Holzapfel, W L; Altamirano, P; Bronfman, L; Casassus, S; May, J; Joy, M

    2003-01-01

    Using the Cosmic Background Imager, a 13-element interferometer array operating in the 26-36 GHz frequency band, we have observed 40 sq deg of sky in three pairs of fields, each ~ 145 x 165 arcmin, using overlapping pointings (mosaicing). We present images and power spectra of the cosmic microwave background radiation in these mosaic fields. We remove ground radiation and other low-level contaminating signals by differencing matched observations of the fields in each pair. The primary foreground contamination is due to point sources (radio galaxies and quasars). We have subtracted the strongest sources from the data using higher-resolution measurements, and we have projected out the response to other sources of known position in the power-spectrum analysis. The images show features on scales ~ 6 - 15 arcmin, corresponding to masses ~ (5 - 80)*10^{14} Msun at the surface of last scattering, which are likely to be the seeds of clusters of galaxies. The power spectrum estimates have a resolution Delta-l = 200 an...

  15. Background and introduction: Chapter 1

    Science.gov (United States)

    Shafroth, Patrick B.

    2010-01-01

    The Salt Cedar and Russian Olive Control Demonstration Act of 2006 (Public Law 109-320; hereafter the Act) directs the Department of the Interior to submit a report to Congress1 that includes an assessment of several issues surrounding these two nonnative trees, now dominant components of the vegetation along many rivers in the Western United States. Specifically, the Act calls for “…an assessment of the extent of salt cedar and Russian olive infestation on public and private land in the western United States,” which shall“A) consider existing research on methods to control salt cedar and Russian olive trees; B) consider the feasibility of reducing water consumption by salt cedar and Russian olive trees; C) consider methods of and challenges associated with the revegetation or restoration of infested land; and D) estimate the costs of destruction of salt cedar and Russian olive trees, related biomass removal, and revegetation or restoration and maintenance of the infested land.”Finally, the Act calls for discussion of“(i) long-term management and funding strategies…that could be implemented by Federal, State, tribal, and private land managers and owners to address the infestation by salt cedar and Russian olive; (ii) any deficiencies in the assessment or areas for additional study; and (iii) any field demonstrations that would be useful in the effort to control salt cedar and Russian olive.”The primary intent of this report is to provide the science assessment called for under the Act. A secondary purpose is to provide a common background for applicants for prospective demonstration projects, should funds be appropriated for this second phase of the Act. In addition to relying on the direction provided under Section C of the Act, the authors of this report also drew upon the detailed list of considerations presented in Section E of the Act to guide development of more expansive discussions of topics relevant to saltcedar and Russian olive control

  16. The tumor suppressor gene TRC8/RNF139 is disrupted by a constitutional balanced translocation t(8;22(q24.13;q11.21 in a young girl with dysgerminoma

    Directory of Open Access Journals (Sweden)

    Fiorio Patrizia

    2009-07-01

    Full Text Available Abstract Background RNF139/TRC8 is a potential tumor suppressor gene with similarity to PTCH, a tumor suppressor implicated in basal cell carcinomas and glioblastomas. TRC8 has the potential to act in a novel regulatory relationship linking the cholesterol/lipid biosynthetic pathway with cellular growth control and has been identified in families with hereditary renal (RCC and thyroid cancers. Haploinsufficiency of TRC8 may facilitate development of clear cell-RCC in association with VHL mutations, and may increase risk for other tumor types. We report a paternally inherited balanced translocation t(8;22 in a proposita with dysgerminoma. Methods The translocation was characterized by FISH and the breakpoints cloned, sequenced, and compared. DNA isolated from normal and tumor cells was checked for abnormalities by array-CGH. Expression of genes TRC8 and TSN was tested both on dysgerminoma and in the proposita and her father. Results The breakpoints of the translocation are located within the LCR-B low copy repeat on chromosome 22q11.21, containing the palindromic AT-rich repeat (PATRR involved in recurrent and non-recurrent translocations, and in an AT-rich sequence inside intron 1 of the TRC8 tumor-suppressor gene at 8q24.13. TRC8 was strongly underexpressed in the dysgerminoma. Translin is underexpressed in the dysgerminoma compared to normal ovary. TRC8 is a target of Translin (TSN, a posttranscriptional regulator of genes transcribed by the transcription factor CREM-tau in postmeiotic male germ cells. Conclusion A role for TRC8 in dysgerminoma may relate to its interaction with Translin. We propose a model in which one copy of TRC8 is disrupted by a palindrome-mediated translocation followed by complete loss of expression through suppression, possibly mediated by miRNA.

  17. Whitening of Background Brain Activity via Parametric Modeling

    Directory of Open Access Journals (Sweden)

    Nidal Kamel

    2007-01-01

    Full Text Available Several signal subspace techniques have been recently suggested for the extraction of the visual evoked potential signals from brain background colored noise. The majority of these techniques assume the background noise as white, and for colored noise, it is suggested to be whitened, without further elaboration on how this might be done. In this paper, we investigate the whitening capabilities of two parametric techniques: a direct one based on Levinson solution of Yule-Walker equations, called AR Yule-Walker, and an indirect one based on the least-squares solution of forward-backward linear prediction (FBLP equations, called AR-FBLP. The whitening effect of the two algorithms is investigated with real background electroencephalogram (EEG colored noise and compared in time and frequency domains.

  18. Probing the Universe's Tilt with the Cosmic Infrared Background Dipole

    CERN Document Server

    Fixsen, D J

    2011-01-01

    Conventional interpretation of the observed cosmic microwave background (CMB) dipole is that all of it is produced by local peculiar motions. Alternative explanations requiring part of the dipole to be primordial have received support from measurements of large-scale bulk flows. A test of the two hypothesis is whether other cosmic dipoles produced by collapsed structures later than last scattering coincide with the CMB dipole. One background is the cosmic infrared background (CIB) whose absolute spectrum was measured to ~30% by the COBE satellite. Over the 100 to 500 um wavelength range its spectral energy distribution can provide a probe of its alignment with CMB. This is tested with the COBE FIRAS dataset which is available for such a measurement because of its low noise and frequency resolution important for Galaxy subtraction. Although the FIRAS instrument noise is in principle low enough to determine the CIB dipole, the Galactic foreground is sufficiently close spectrally to keep the CIB dipole hidden. A...

  19. RanBPM is an acetylcholinesterase-interacting protein that translocates into the nucleus during apoptosis

    Institute of Scientific and Technical Information of China (English)

    Xiaowen Gong; Weiyuan Ye; Haibo Zhou; Xiaohui Ren; Zhigang Li; Weiyin Zhou; Jun Wu; Yicheng Gong; Qi Ouyang; Xiaolin Zhao; Xuejun Zhang

    2009-01-01

    Acetylcholinesterase (ACHE) expression may be induced during apoptosis in various cell types. Here, we used the C-terminal of AChE to screen the human fetal brain library and found that it interacted with Ran-binding protein in the microtubule-organizing center (RanBPM). This interaction was further con-firmed by coimmunoprecipitation analysis. In HEK293T cells, RanBPM and AChE were hetero-geneously expressed in the cisplatin-untreated cyto-plasmic extracts and in the cisplatin-treated cytoplasmic or nuclear extracts. Our previous studies performed using morphologic methods have shown that AChE translocates from the cytoplasm to the nucleus during apoptosis. Taken together, these results suggest that RanBPM is an AChE-interacting protein that is translocated from the cytoplasm into the nucleus during apoptosis, similar to the trans-location observed in case of ACHE.

  20. A new translocation between chromosomes 6 and 9 helps to establish diagnosis of renal oncocytoma.

    Science.gov (United States)

    Hudacko, Rachel; May, Michael; Aviv, Hana

    2011-08-01

    Renal oncocytomas are benign epithelial tumors of the kidney. Histologically, they resemble certain malignant renal tumors, such as chromophobe renal cell carcinoma and the eosinophilic or granular form of clear cell renal carcinoma. It is, therefore, important to be able to differentiate among these tumors. Cytogenetic analysis is an important adjunct to the diagnosis of renal tumors, as the various subtypes have specific acquired chromosome abnormalities. Oncocytomas present either with loss of chromosome 1 and a sex chromosome, or with recurring translocations involving chromosome 11. We describe 2 patients with renal oncocytoma and a new translocation between chromosomes 6 and 9. The tumors in both patients were histologically virtually identical. The t(6;9)(p21;p23) may be a new translocation associated with renal oncocytomas.

  1. Assessment of an in vitro model of pulmonary barrier to study the translocation of nanoparticles

    Directory of Open Access Journals (Sweden)

    Samir Dekali

    2014-01-01

    The use of Calu-3 cells allowed high transepithelial electrical resistance (TEER values (>1000 Ω cm2 in co-cultures with or without macrophages. After 24 h of exposure to non-cytotoxic concentrations of non-functionalized PS nanobeads, the relative TEER values (%/t0 were significantly decreased in co-cultures. Epithelial cells and macrophages were able to internalize PS nanobeads. Regarding translocation, Transwell® membranes per se limit the passage of nanoparticles between apical and basal side. However, small non-functionalized PS nanobeads (51 nm were able to translocate as they were detected in the basal side of co-cultures. Altogether, these results show that this co-culture model present good barrier properties allowing the study of nanoparticle translocation but research effort need to be done to improve the neutrality of the porous membrane delimitating apical and basal sides of the model.

  2. Stem-spermatogonial survival and incidence of reciprocal translocations in the. gamma. -irradiated boar

    Energy Technology Data Exchange (ETDEWEB)

    Erickson, B.H.; Martin, P.G.

    1984-01-01

    To assess the effects of ..gamma..-radiation on stem-cell survival and incidence of reciprocal translocations, boar testes were irradiated with 100, 200, or 400 rad. Stem-cell survival was markedly affected by 100 rad (51% of control) and reduced to 34% of control by 400 rad. Production of differentiating spermatogonia was all but completely interrupted by 200 rad and spermatogonial renewal was incomplete at 12 weeks. From the state of the seminiferous epithelium at 12 weeks, estimates of the percentage of permanent impairment of sperm-producing capacity ranged from 20 +/- 6 (100 rad) to 67 +/- 10 (400 rad). Incidence of translocations peaked at 200 rad and the number occurring at 100 and 400 rad was similar. Kinetics of porcine spermatogonial renewal differs considerably from those of the rodent and, relative to the rodent, this may account for the boar's higher sensitivity to stem-cell killing and lower sensitivity to translocations.

  3. Contraction-associated translocation of protein kinase C in rat skeletal muscle

    DEFF Research Database (Denmark)

    Richter, Erik; Cleland, P J; Rattigan, S

    1987-01-01

    Electrical stimulation of the sciatic nerve of the anaesthetized rat in vivo led to a time-dependent translocation of protein kinase C from the muscle cytosol to the particulate fraction. Maximum activity of protein kinase C in the particulate fraction occurred after 2 min of intermittent short t...... tetanic contractions of the gastrocnemius-plantaris-soleus muscle group and coincided with the loss of activity from the cytosol. Translocation of protein kinase C may imply a role for this kinase in contraction-initiated changes in muscle metabolism.......Electrical stimulation of the sciatic nerve of the anaesthetized rat in vivo led to a time-dependent translocation of protein kinase C from the muscle cytosol to the particulate fraction. Maximum activity of protein kinase C in the particulate fraction occurred after 2 min of intermittent short...

  4. Repatriation and translocation of ungulates into South African national parks: an assessment of past attempts

    Directory of Open Access Journals (Sweden)

    P.A. Novellie

    1994-09-01

    Full Text Available The results of 36 attempts to repatriate or translocate ungulates into South African national parks are examined. Habitat suitability appeared to be an important factor influencing the success rate. Of six cases in which individuals were translocated outside the range occupied by the species in historical times, only one succeeded. Of 10 cases where the park was within the historical range of the species but the habitat was rated as unsuitable (little or none of the required habitat present in the park only one succeeded. In contrast 17 out of 20 cases in which the habitat was classified as adequate resulted in success. The repatriation and translocation attempts were poorly documented and this hampered identification of the factors associated with success.

  5. Molecular signals regulating translocation and toxicity of graphene oxide in the nematode Caenorhabditis elegans

    Science.gov (United States)

    Wu, Qiuli; Zhao, Yunli; Li, Yiping; Wang, Dayong

    2014-09-01

    Both in vitro and in vivo studies have demonstrated the toxic effects of graphene oxide (GO). However, the molecular basis for the translocation and toxicity of GO is still largely unclear. In the present study, we employed an in vivo Caenorhabditis elegans assay system to identify molecular signals involved in the control of the translocation and toxicity of GO. We identified 7 genes whose mutations altered both the translocation and toxicity of GO. Mutations of the hsp-16.48, gas-1, sod-2, sod-3, and aak-2 genes caused greater GO translocation into the body and toxic effects on both primary and secondary targeted organs compared with wild type; however, mutations of the isp-1 and clk-1 genes resulted in significantly decreased GO translocation into the body and toxicity on both primary and secondary targeted organs compared with wild-type. Moreover, mutations of the hsp-16.48, gas-1, sod-2, sod-3, and aak-2 genes caused increased intestinal permeability and prolonged mean defecation cycle length in GO-exposed nematodes, whereas mutations of the isp-1 and clk-1 genes resulted in decreased intestinal permeability in GO-exposed nematodes. Therefore, for the underlying mechanism, we hypothesize that both intestinal permeability and defecation behavior may have crucial roles in controlling the functions of the identified molecular signals. The molecular signals may further contribute to the control of transgenerational toxic effects of GO. Our results provide an important insight into understanding the molecular basis for the in vivo translocation and toxicity of GO.Both in vitro and in vivo studies have demonstrated the toxic effects of graphene oxide (GO). However, the molecular basis for the translocation and toxicity of GO is still largely unclear. In the present study, we employed an in vivo Caenorhabditis elegans assay system to identify molecular signals involved in the control of the translocation and toxicity of GO. We identified 7 genes whose mutations

  6. KIAA1524: A novel MLL translocation partner in acute myeloid leukemia.

    Science.gov (United States)

    Coenen, Eva A; Zwaan, C Michel; Meyer, Claus; Marschalek, Rolf; Pieters, Rob; van der Veken, Lars T; Beverloo, H Berna; van den Heuvel-Eibrink, Marry M

    2011-01-01

    The Mixed Lineage Leukemia gene on chromosome 11q23 is a frequent site of recurrent translocations in acute leukemias. Its promiscuous character is reflected by the more than 60 different translocation partners described in literature. Prompted by karyotype and atypical FISH results, we identified a new translocation partner in infant acute myeloid leukemia, KIAA1524 on 3q13.13, also known as 'Cancerous Inhibitor of Protein phosphatase 2A (CIP2A)'. This gene was recently identified as a proto-oncogene stabilizing MYC protein in gastric carcinoma. KIAA1524 has never been related to hematologic malignancies before, and the current AML case is the first case in which an MLL-KIAA1524 fusion was described.

  7. Fusidic acid targets elongation factor G in several stages of translocation on the bacterial ribosome.

    Science.gov (United States)

    Borg, Anneli; Holm, Mikael; Shiroyama, Ikue; Hauryliuk, Vasili; Pavlov, Michael; Sanyal, Suparna; Ehrenberg, Måns

    2015-02-06

    The antibiotic fusidic acid (FA) targets elongation factor G (EF-G) and inhibits ribosomal peptide elongation and ribosome recycling, but deeper mechanistic aspects of FA action have remained unknown. Using quench flow and stopped flow experiments in a biochemical system for protein synthesis and taking advantage of separate time scales for inhibited (10 s) and uninhibited (100 ms) elongation cycles, a detailed kinetic model of FA action was obtained. FA targets EF-G at an early stage in the translocation process (I), which proceeds unhindered by the presence of the drug to a later stage (II), where the ribosome stalls. Stalling may also occur at a third stage of translocation (III), just before release of EF-G from the post-translocation ribosome. We show that FA is a strong elongation inhibitor (K50% ≈ 1 μm), discuss the identity of the FA targeted states, and place existing cryo-EM and crystal structures in their functional context.

  8. Rab8A regulates insulin-stimulated GLUT4 translocation in C2C12 myoblasts.

    Science.gov (United States)

    Li, Hanbing; Ou, Liting; Fan, Jiannan; Xiao, Mei; Kuang, Cuifang; Liu, Xu; Sun, Yonghong; Xu, Yingke

    2017-02-01

    Rab proteins are important regulators of GLUT4 trafficking in muscle and adipose cells. It is still unclear which Rabs are involved in insulin-stimulated GLUT4 translocation in C2C12 myoblasts. In this study, we detect the colocalization of Rab8A with GLUT4 and the presence of Rab8A at vesicle exocytic sites by TIRFM imaging. Overexpression of dominant-negative Rab8A (T22N) diminishes insulin-stimulated GLUT4 translocation, while constitutively active Rab8A (Q67L) augments it. In addition, knockdown of Rab8A inhibits insulin-stimulated GLUT4 translocation, which is rescued by replenishment of RNAi-resistant Rab8A. Together, these results indicate an indispensable role for Rab8A in insulin-regulated GLUT4 trafficking in C2C12 cells.

  9. (52)Fe translocation in barley as monitored by a positron-emitting tracer imaging system (PETIS): evidence for the direct translocation of Fe from roots to young leaves via phloem.

    Science.gov (United States)

    Tsukamoto, Takashi; Nakanishi, Hiromi; Uchida, Hiroshi; Watanabe, Satoshi; Matsuhashi, Shinpei; Mori, Satoshi; Nishizawa, Naoko K

    2009-01-01

    The real-time translocation of iron (Fe) in barley (Hordeum vulgare L. cv. Ehimehadaka no. 1) was visualized using the positron-emitting tracer (52)Fe and a positron-emitting tracer imaging system (PETIS). PETIS allowed us to monitor Fe translocation in barley non-destructively under various conditions. In all cases, (52)Fe first accumulated at the basal part of the shoot, suggesting that this region may play an important role in Fe distribution in graminaceous plants. Fe-deficient barley showed greater translocation of (52)Fe from roots to shoots than did Fe-sufficient barley, demonstrating that Fe deficiency causes enhanced (52)Fe uptake and translocation to shoots. In the dark, translocation of (52)Fe to the youngest leaf was equivalent to or higher than that under the light condition, while the translocation of (52)Fe to the older leaves was decreased, in both Fe-deficient and Fe-sufficient barley. This suggests the possibility that the mechanism and/or pathway of Fe translocation to the youngest leaf may be different from that to the older leaves. When phloem transport in the leaf was blocked by steam treatment, (52)Fe translocation from the roots to older leaves was not affected, while (52)Fe translocation to the youngest leaf was reduced, indicating that Fe is translocated to the youngest leaf via phloem in addition to xylem. We propose a novel model in which root-absorbed Fe is translocated from the basal part of the shoots and/or roots to the youngest leaf via phloem in graminaceous plants.

  10. Safety evaluation of probiotic bifidobacteria by analysis of mucin degradation activity and translocation ability.

    Science.gov (United States)

    Abe, Fumiaki; Muto, Masamichi; Yaeshima, Tomoko; Iwatsuki, Keiji; Aihara, Hiroaki; Ohashi, Yuji; Fujisawa, Tomohiko

    2010-04-01

    Although probiotic-containing nutrient formulas for infants and toddlers have become very popular, some adverse effects related to translocation of probiotic strains have been reported. We assessed the safety of probiotic bifidobacteria that have been used in clinical investigations and proven to have beneficial effects, by analyzing mucin degradation activity and translocation ability. Mucin degradation activities of three probiotic bifidobacteria strains; Bifidobacterium longum BB536, Bifidobacterium breve M-16V and Bifidobacterium infantis M-63, were evaluated by three in vitro tests comprising growth in liquid medium, SDS-PAGE analysis of degraded mucin residues, and degradation assay in Petri dish. All test strains and control type strains failed to grow in the liquid medium containing mucin as the only carbon source, although good growth was obtained from fecal sample. In the SDS-PAGE analyses of mucin residues and observation of mucinolytic zone in agar plate, the three test strains also showed no mucin degradation activity as the type strains, although fecal sample yielded positive results. In another study, a high dose of B. longum BB536 was administered orally to conventional mice to examine the translocation ability. No translocation into blood, liver, spleen, kidney and mesenteric lymph nodes was observed and no disturbance of epithelial cells and mucosal layer in the ileum, cecum and colon was detected, indicating that the test strain had no translocation ability and induced no damage to intestinal surface. These results resolve the concern about bacterial translocation when using bifidobacteria strains as probiotics, which have been tested in various clinical trials, supporting the continuous use of these probiotic strains without anxiety.

  11. Rewilding the tropics, and other conservation translocations strategies in the tropical Asia-Pacific region.

    Science.gov (United States)

    Louys, Julien; Corlett, Richard T; Price, Gilbert J; Hawkins, Stuart; Piper, Philip J

    2014-11-01

    Alarm over the prospects for survival of species in a rapidly changing world has encouraged discussion of translocation conservation strategies that move beyond the focus of 'at-risk' species. These approaches consider larger spatial and temporal scales than customary, with the aim of recreating functioning ecosystems through a combination of large-scale ecological restoration and species introductions. The term 'rewilding' has come to apply to this large-scale ecosystem restoration program. While reintroductions of species within their historical ranges have become standard conservation tools, introductions within known paleontological ranges-but outside historical ranges-are more controversial, as is the use of taxon substitutions for extinct species. Here, we consider possible conservation translocations for nine large-bodied taxa in tropical Asia-Pacific. We consider the entire spectrum of conservation translocation strategies as defined by the IUCN in addition to rewilding. The taxa considered are spread across diverse taxonomic and ecological spectra and all are listed as 'endangered' or 'critically endangered' by the IUCN in our region of study. They all have a written and fossil record that is sufficient to assess past changes in range, as well as ecological and environmental preferences, and the reasons for their decline, and they have all suffered massive range restrictions since the late Pleistocene. General principles, problems, and benefits of translocation strategies are reviewed as case studies. These allowed us to develop a conservation translocation matrix, with taxa scored for risk, benefit, and feasibility. Comparisons between taxa across this matrix indicated that orangutans, tapirs, Tasmanian devils, and perhaps tortoises are the most viable taxa for translocations. However, overall the case studies revealed a need for more data and research for all taxa, and their ecological and environmental needs. Rewilding the Asian-Pacific tropics remains

  12. Induction of nuclear translocation of NF-kappaB in epithelial cells by respirable mineral fibres.

    Science.gov (United States)

    Brown, D M; Beswick, P H; Donaldson, K

    1999-10-01

    A panel of mineral fibres has been studied for their ability to cause translocation of the transcription factor NF-kappaB to the nucleus in A549 lung epithelial cells. On the basis of inhalation studies, three fibres were designated as being carcinogenic-amosite asbestos, silicon carbide and refractory ceramic fibre 1 (RCF1)-or non-carcinogenic-man-made vitreous fibre (MMVF10), Code 100/475 glass fibre, and RCF4. The experiments were carried out at equal fibre number. It was hypothesized that carcinogenic fibres have greater free radical activity than non-carcinogenic fibres and that an oxidative stress produced in the lung after inhalation of fibres could cause translocation of the transcription factor NF-kappaB to the nucleus, where transcription of pro-inflammatory genes such as cytokines could occur. It was demonstrated that a simple oxidant, hydrogen peroxide, caused translocation in a time- and dose-dependent manner. The three carcinogenic fibres produced a significant dose-dependent translocation of NF-kappaB to the nucleus, whereas the non-carcinogenic fibres did not. Silicon carbide fibres were the most potent of the pathogenic fibres. MMVF10 was the most potent of the non-pathogenic fibres, causing significant nuclear translocation of NF-kappaB at high fibre number. Using three antioxidants, curcumin, pyrrolidine dithiocarbamate, and Nacystelin, translocation caused by carcinogenic fibres could be significantly reduced. The present study shows that a short-term in vitro assay can discriminate between pathogenic and non-pathogenic fibres in terms of a key pro-inflammatory event in epithelial cells. The mechanism of the activation of NF-kappaB by pathogenic fibres and its general applicability to other fibre types remain to be determined.

  13. Dynamics of Polymer Translocation: A Short Review with an Introduction of Weakly-Driven Regime

    Directory of Open Access Journals (Sweden)

    Takahiro Sakaue

    2016-12-01

    Full Text Available As emphasized in a recent review (by V.V. Palyulin, T. Ala-Nissila, R. Metzler, theoretical understanding of the unbiased polymer translocation lags behind that of the (strongly driven translocation. Here, we suggest the introduction of a weakly-driven regime, as described by the linear response theory to the unbiased regime, which is followed by the strongly-driven regime beyond the onset of nonlinear response. This provides a concise crossover scenario, bridging the unbiased to strongly-driven regimes.

  14. Translocation of Biopolymer Chain Through a Nanopore: Coil-Helix Transition

    Institute of Scientific and Technical Information of China (English)

    GU Fang; WANG Hai-Jun; HONG Xiao-Zhong; BA Xin-Wu

    2008-01-01

    @@ The translocation dynamics of a single biopolymer chain through a nanopore in a membrane is investigated by taking the coil-helix transition into account. Based on the changing of the free energy due to the coil-helix transition, the mean first passage time τ is obtained, and then the corresponding numerical simulations are presented under different conditions. It is shown that the coil helix transition can significantly shorten the translocation time of the biopolymer chain. In addition, we also discuss the scaling behaviour for τ with the chain length N and some related problems.

  15. ARTICLES: Effect of Interaction upon Translocation of Confined Polymer Chain Through Nanopore

    Science.gov (United States)

    Wang, Yao; Xie, Yong-jun; Yang, Hai-yang; Zhang, Xing-yuan

    2010-06-01

    The effect of the interaction between nanopore and chain monomer on the translocation of a single polymer chain confined in a finite size square through an interacting nanopore to a large space has been studied by two-dimensional bond fluctuation model with Monte Carlo simulation. Results indicate that the free energy barrier before the successful translocation of the chain depends linearly on the chain length as well as the nanopore length for different pore-polymer interaction, and the attractive interaction reduces the free energy barrier, leading to the reduction of the average trapping time.

  16. The Novel Dipeptide Translocator Protein Ligand, Referred to As GD-23, Exerts Anxiolytic and Nootropic Activities

    OpenAIRE

    2015-01-01

    The translocator protein (TSPO) promotes the translocation of cholesterol to the inner mitochondrial membrane and mediates steroid formation. In this study, we first report on a biological evaluation of the dipeptide GD-23 (N-carbobenzoxy-L tryptophanyl-L isoleucine amide), a structural analogue of Alpidem, the principal TSPO ligand. We show that GD-23 in a dose range of 0.05 to 0.5 mg/kg (i.p.) exhibits anxiolytic activity in the elevated plus maze test and nootropic activity in the object r...

  17. Kinetics of contraction-induced GLUT4 translocation in skeletal muscle fibers from living mice

    DEFF Research Database (Denmark)

    Lauritzen, Hans Peter M. Mortensen; Galbo, Henrik; Toyoda, Taro

    2010-01-01

    Exercise is an important strategy for the treatment of type 2 diabetes. This is due in part to an increase in glucose transport that occurs in the working skeletal muscles. Glucose transport is regulated by GLUT4 translocation in muscle, but the molecular machinery mediating this process is poorly...... understood. The purpose of this study was to 1) use a novel imaging system to elucidate the kinetics of contraction-induced GLUT4 translocation in skeletal muscle and 2) determine the function of AMP-activated protein kinase alpha2 (AMPKalpha2) in this process....

  18. Multipurpose background for standardization in medical photography.

    Science.gov (United States)

    Hallock, G G

    1985-08-01

    A dual photography background system consisting of a quadrilled format on one side and a plain background on the other is described. It is mobile and efficient as a space- and time-saving device for medical photography.

  19. [National Elk Refuge background and operating statement

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a background on National Elk Refuge in Wyoming. Part I is solely background information concerning the physical characteristics, habitat, major...

  20. Multi-frequency excitation

    KAUST Repository

    Younis, Mohammad I.

    2016-03-10

    Embodiments of multi-frequency excitation are described. In various embodiments, a natural frequency of a device may be determined. In turn, a first voltage amplitude and first fixed frequency of a first source of excitation can be selected for the device based on the natural frequency. Additionally, a second voltage amplitude of a second source of excitation can be selected for the device, and the first and second sources of excitation can be applied to the device. After applying the first and second sources of excitation, a frequency of the second source of excitation can be swept. Using the methods of multi- frequency excitation described herein, new operating frequencies, operating frequency ranges, resonance frequencies, resonance frequency ranges, and/or resonance responses can be achieved for devices and systems.

  1. Fluid in Rectangular Tank – Frequency Analysis

    Directory of Open Access Journals (Sweden)

    Kotrasová Kamila

    2014-06-01

    Full Text Available Ground-supported tanks are used to store a variety of liquids. During earthquake activity the liquid exerts impulsive and convective pressures (sloshing on the walls and bottom of the rectangular tank. This paper provides theoretical background for analytical calculating of circular frequencies and hydrodynamic pressures developed during an earthquake in rectangular container. Analytical results of first natural frequency are compared with experiment.

  2. 16 CFR 1101.1 - General background.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false General background. 1101.1 Section 1101.1 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS INFORMATION DISCLOSURE UNDER SECTION 6(b) OF THE CONSUMER PRODUCT SAFETY ACT Background § 1101.1 General background. (a) Basic purpose. This rule sets...

  3. Backgrounds in Boundary String Field Theory

    CERN Document Server

    Baumgartl, M

    2009-01-01

    We study the role of closed string backgrounds in boundary string field theory. Background independence requires the introduction of dual boundary fields, which are reminiscent of the doubled field formalism. We find a correspondence between closed string backgrounds and collective excitations of open strings described by vertex operators involving dual fields. Renormalization group flow, solutions and stability are discussed in an example.

  4. Translocation of PEGylated quantum dots across rat alveolar epithelial cell monolayers

    Directory of Open Access Journals (Sweden)

    Fazlollahi F

    2011-11-01

    Full Text Available Farnoosh Fazlollahi1,8, Arnold Sipos1,2, Yong Ho Kim1,2, Sarah F Hamm-Alvarez6, Zea Borok1–3, Kwang-Jin Kim1,2,5–7, Edward D Crandall1,2,4,8 1Will Rogers Institute Pulmonary Research Center, 2Department of Medicine, 3Department of Biochemistry and Molecular Biology, 4Department of Pathology, 5Department of Physiology and Biophysics, 6Department of Pharmacology and Pharmaceutical Sciences, 7Department of Biomedical Engineering, 8Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA, USA Background: In this study, primary rat alveolar epithelial cell monolayers (RAECM were used to investigate transalveolar epithelial quantum dot trafficking rates and underlying transport mechanisms. Methods: Trafficking rates of quantum dots (PEGylated CdSe/ZnS, core size 5.3 nm, hydrodynamic size 25 nm in the apical-to-basolateral direction across RAECM were determined. Changes in bioelectric properties (ie, transmonolayer resistance and equivalent active ion transport rate of RAECM in the presence or absence of quantum dots were measured. Involvement of endocytic pathways in quantum dot trafficking across RAECM was assessed using specific inhibitors (eg, methyl-ß-cyclodextrin, chlorpromazine, and dynasore for caveolin-, clathrin-, and dynamin-mediated endocytosis, respectively. The effects of lowering tight junctional resistance on quantum dot trafficking were determined by depleting Ca2+ in apical and basolateral bathing fluids of RAECM using 2 mM EGTA. Effects of temperature on quantum dot trafficking were studied by lowering temperature from 37°C to 4°C. Results: Apical exposure of RAECM to quantum dots did not elicit changes in transmonolayer resistance or ion transport rate for up to 24 hours; quantum dot trafficking rates were not surface charge-dependent; methyl-ß-cyclodextrin, chlorpromazine, and dynasore did not decrease quantum dot trafficking rates; lowering of temperature

  5. Xp11.2 translocation renal cell carcinoma occurring during pregnancy with a novel translocation involving chromosome 19: a case report with review of the literature

    Directory of Open Access Journals (Sweden)

    Surti Urvashi

    2009-05-01

    Full Text Available Abstract The recently recognized renal cell carcinomas (RCCs associated with Xp11.2 translocations (TFE3 transcription factor gene fusions are rare tumors predominantly reported in children. They comprise at least one-third of pediatric RCCs and only few adult cases have been reported. Here, we present a case of Xp11.2 translocation RCC in 26-year-old pregnant female. Her routine antenatal ultrasonography accidentally found a complex cystic right renal mass. Further radiologic studies revealed unilocular cyst with multiple mural nodules at inferior pole of right kidney, which was suspicious for RCC. She underwent right radical nephrectomy at 15 weeks gestation. Macroscopically, the cystic tumor was well encapsulated with multiple friable mural nodules on its inner surface. Microscopically, the tumor consisted of clear and eosinophilic/oncocytic voluminous cells arranged in papillary, trabecular, and nested/alveolar patterns. Occasional hyaline nodules and numerous psammoma bodies were present. Immunohistochemically, the tumor showed strong nuclear positivity for TFE3. Epithelial membrane antigen, CD10, and E-cadherin were strongly positive. Cytokeratin AE1/AE3, cytokeratin CAM-5.2, calveolin, and parvalbumin were moderately positive. Cytokeratin 7, renal cell carcinoma antigen, and colloidal iron were focally weakly positive. BerEP4 and carbonic anhydrase IX were negative. Cytogenetically, the tumor harbored a novel variant translocation involving chromosomes X and 19, t(X;19(p11.2;q13.1. Interphase FISH analysis performed on cultured and uncultured tumor cells using a dual-color break-apart DNA probe within the BCL3 gene on 19q13.3 was negative for the BCL3 gene rearrangement. She received no adjuvant therapy, delivered a normal term baby five months later, and is alive without evidence of disease 27 months after diagnosis and surgery. Unlike most recently reported Xp11.2 translocation RCCs in adult patients with aggressive clinical course

  6. Construindo uma política feminista translocal da tradução Enacting a Translocal Feminist Politics of Translation

    Directory of Open Access Journals (Sweden)

    Sonia E Alvarez

    2009-12-01

    Full Text Available Nosso projeto coletivo Translocalities/Translocalidades: Feminist Politics of Translation in the Latin/a Américas (Políticas Feministas de Tradução na América Latina explora como discursos e práticas feministas viajam por uma variedade de lugares e direções e acabam se tornando paradigmas interpretativos para a leitura/escrita de questões de classe, gênero, sexualidade, migração, saúde, cidadania, política e circulação de identidades e textos. Sustentamos que a tradução é política e teoricamente indispensável para forjar epistemologias e alianças políticas feministas, antirracistas e pós-coloniais/pós-ocidentais, pois as Américas Latinas - enquanto formação cultural transfronteiriça e não territorialmente delimitada - devem ser entendidas como translocais em dois sentidos. O primeiro sentido que usamos - o de translocalidade - parte de movimentos além das concepções da "política da localização" empregadas pelo feminismo terceiro-mundista estadunidense. Mais do que "migrar" e "se assimilar", muitas pessoas nas Américas Latinas cada vez mais se movem de um lado para outro entre localidades, entre lugares historicamente situados e culturalmente específicos, ainda que porosos, atravessando múltiplas fronteiras, e não apenas entre nações (como deixa a entender o termo "migração transnacional", por exemplo. Empregamos a expressão translocal, então, em um segundo sentido, que chamamos de translocalidades, precisamente para capturar esses cruzamentos e movimentos multidirecionaisOur collective project on Translocalities/Translocalidades: Feminist Politics of Translation in the Latin/a Américas explores how feminist discourses and practices travel across a variety of sites and directionalities to become interpretive paradigms to read/write issues of class, gender, race, sexuality, migration, health, social movements, citizenship, politics, and the circulation of identities and texts. Translation is

  7. Application of Argo-derived background diapycnal mixing in HYCOM

    Science.gov (United States)

    Deng, Zengan; Yu, Ting

    2014-09-01

    Internal wave-induced background diapycnal mixing (DM) in the upper 2000 m of the global ocean, which primarily depends on the local inertial frequency, is calculated based on Argo observations using the newly published Thermodynamic Equation of Seawater-2010 (IOC, SCOR and IAPSO, 2010). This spatially dependent background DM agrees well with previous theoretical and observational mixing estimates. More importantly, the DM data are gridded, which renders the data suitable for modeling applications. The implementation of these data in the HYbrid Coordinate Ocean Model (HYCOM) demonstrates the potential for their application in numerical ocean models. Three numerical experiments that are specifically designed with different DM settings reveal that the meridional overturning circulation (MOC), temperature and salinity in the Atlantic change substantially when the constant background DM is replaced with Argo-derived mixing. Tropical and high-latitude regions that are considered important for global climate are identified as the areas that are most sensitive to the magnitude of the background DM. Compared with constant background DM, the enhanced mid-latitude DM most likely contributes substantially to the MOC transport. Thus, although room remains for improvement, the spatially varying DM derived in the present study may facilitate global circulation and climate modeling.

  8. A method of background noise cancellation for SQUID applications

    Energy Technology Data Exchange (ETDEWEB)

    He, D F [Iwate Industrial Promotion Center, Morioka 020-0045 (Japan); Yoshizawa, M [Faculty of Engineering, Iwate University, Morioka 020-8551 (Japan)

    2003-12-01

    When superconducting quantum inference devices (SQUIDs) operate in low-cost shielding or unshielded environments, the environmental background noise should be reduced to increase the signal-to-noise ratio. In this paper we present a background noise cancellation method based on a spectral subtraction algorithm. We first measure the background noise and estimate the noise spectrum using fast Fourier transform (FFT), then we subtract the spectrum of background noise from that of the observed noisy signal and the signal can be reconstructed by inverse FFT of the subtracted spectrum. With this method, the background noise, especially stationary inferences, can be suppressed well and the signal-to-noise ratio can be increased. Using high-T{sub C} radio-frequency SQUID gradiometer and magnetometer, we have measured the magnetic field produced by a watch, which was placed 35 cm under a SQUID. After noise cancellation, the signal-to-noise ratio could be greatly increased. We also used this method to eliminate the vibration noise of a cryocooler SQUID.

  9. Nonreciprocal chromosomal translocations in renal cancer involve multiple DSBs and NHEJ associated with breakpoint inversion but not necessarily with transcription.

    Science.gov (United States)

    Ali, Hanif; Daser, Angelika; Dear, Paul; Wood, Henry; Rabbitts, Pamela; Rabbitts, Terence

    2013-04-01

    Chromosomal translocations and other abnormalities are central to the initiation of cancer in all cell types. Understanding the mechanism is therefore important to evaluate the evolution of cancer from the cancer initiating events to overt disease. Recent work has concentrated on model systems to develop an understanding of the molecular mechanisms of translocations but naturally occurring events are more ideal case studies since biological selection is absent from model systems. In solid tumours, nonreciprocal translocations are most commonly found, and accordingly we have investigated the recurrent nonreciprocal t(3;5) chromosomal translocations in renal carcinoma to better understand the mechanism of these naturally occurring translocations in cancer. Unexpectedly, the junctions of these translocations can be associated with site-specific, intrachromosomal inversion involving at least two double strand breaks (DSB) in cis and rejoining by nonhomologous end joining or micro-homology end joining. However, these translocations are not necessarily associated with transcribed regions questioning accessibility per se in controlling these events. In addition, intrachromosomal deletions also occur. We conclude these naturally occurring, nonreciprocal t(3;5) chromosomal translocations occur after complex and multiple unresolved intrachromosomal DSBs leading to aberrant joining with concurrent interstitial inversion and that clonal selection of cells is the critical element in cancer development emerging from a plethora of DSBs that may not always be pathogenic.

  10. DISTINCT XP11.2 BREAKPOINTS IN 2 RENAL-CELL CARCINOMAS EXHIBITING X-AUTOSOME TRANSLOCATIONS

    NARCIS (Netherlands)

    DIJKHUIZEN, T; VANDENBERG, E; WETERMAN, M; VANKESSEL, AG; STORKEL, S; FOLKERS, RP; BRAAM, A; DEJONG, B

    1995-01-01

    Several human renal cell carcinomas with X;autosome translocations have been reported in recent years. The t(X; I)(p11.2;q21) appears to be a specific primary anomaly, suggesting that tumors with this translocation form a distinct subgroup of RCC. Here we report two new cases, one with a t(X;10)(p11

  11. OK-432 reduces mortality and bacterial translocation in irradiated and granulocyte-colony stimulating factor (G-CSF)-treated mice

    Energy Technology Data Exchange (ETDEWEB)

    Nose, Masako; Uzawa, Akiko; Ogyu, Toshiaki [National Inst. of Radiological Sciences, Chiba (Japan); Suzuki, Gen

    2001-06-01

    Acute radiation induces bacterial translocation from the gut, followed by systemic infection and sepsis. In order to reduce the mortality after acute whole body irradiation, it is essential to control bacterial translocation. In this study, we established a bacterial translocation assay as a sensitive method to detect minor mucosal injury by radiation. By utilizing this assay, we evaluated the adverse effects, if any, of hematopoietic reagents on the mucosal integrity in the respiratory and gastro-intestinal tracts. Bacterial translocation to the liver and spleen occurred after whole-body irradiation if the dose exceeded 6 Gy. The administration of G-CSF unexpectedly increased the bacterial translocation in 8 Gy-irradiated mice. The pharmaceutical preparation of low-virulent Streptococcus pyogenes, OK-432, significantly reduced the endotoxin levels in peripheral blood without any reduction of bacterial translocation. A combined treatment with G-CSF and OK-432 decreased bacterial translocation and prevented death. This result indicates that the early administration of G-CSF has an adverse effect on bacterial translocation, and that a combined treatment of G-CSF and OK-432 attenuates the adverse effect of G-CSF and improves the survival rate after acute irradiation. (author)

  12. A quantitative approach for Cd, Cu, Fe and Mn through laser ablation imaging for evaluating the translocation and accumulation of metals in sunflower seeds.

    Science.gov (United States)

    Pessôa, Gustavo de S; Lopes Júnior, Cícero A; Madrid, Katherine C; Arruda, Marco A Z

    2017-05-15

    The uptake and accumulation of Cd in sunflower seeds represents an important pathway for imputing potentially toxic metals into human and animal food. In this way, bioimaging of Cd and micronutrients (Cu, Fe and Mn) in the seeds of sunflower grown in soil contaminated with Cd are performed. For this task, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is used in quantitative approach, considering four groups: precursor, control, Cd-low (50mg) and Cd-high (700mg). For attaining our proposals, ICP-MS (nebulizer and auxiliary flow rates and radiofrequency power) and LA (laser intensity, frequency and spot size) parameters were optimized, and the analytical signal improved to 197%, 217%, 232%, and 283%, for (57)Fe, (112)Cd, (55)Mn and (63)Cu, respectively. The accuracy of proposed method using LA-ICP-MS is evaluated comparing the CRM results (Tomato leaves, NIST SRM 1573a). No difference is found at 95% confidence level. Regarding Cd accumulation in sunflower seeds, the results indicated that cadmium is translocated to seeds, and the cotyledons showed the highest concentration (Cd-high group), ranging from 10 to 20µgg(-1). Considering both total concentration and the distribution in the seeds, Cd uptake is responsible to the homeostasis misbalance of micronutrients, which play an essential role in the sunflower metabolism. Such results highlight the importance of bioimaging evaluation, in the translocation and accumulation of metals, contributing to expand the information available of this culture.

  13. The translocation t(2;11)(p21;q23) without MLL gene rearrangement--a possible marker of good prognosis in myelodysplastic syndrome patients.

    Science.gov (United States)

    Dvorak, Pavel; Lysak, Daniel; Vokurka, Samuel; Michalova, Kyra; Sarova, Iveta; Jonasova, Anna; Hruba, Martina; Rykovska, Anna; Subrt, Ivan

    2014-06-01

    The translocation t(2;11)(p21;q23) is associated with de novo myelodysplastic syndromes (MDS) and has an overall frequency of approximately 1%. The outcome of MDS patients with this translocation is not clear until now, because most of the clinical data addressing the t(2;11)(p21;q23) has been collected without investigating the status of the mixed lineage leukemia (MLL) gene. In this report, we present seven new patients with MDS diagnosis and the t(2;11)(p21;q23) in bone marrow cells; all of them without MLL gene rearrangement. They were found in two databases consisting of 1185 patients of two Czech institutions. These patients tended to be younger and showed a strong male predominance. A cytological and histological assessment of bone marrow at diagnosis revealed only mild MDS with marked dysplasia in megakaryopoiesis. Similar to other primary abnormalities in MDS (e.g. deletion of 11q), the t(2;11)(p21;q23) was frequently associated with deletion of 5q. Our results stress the common clinicopathological features of this entity and indicate that the t(2;11)(p21;q23) may be associated with a good prognosis for MDS patients (median survival 72 months).

  14. Subtelomeric rearrangements in Indian children with idiopathic intellectual disability/developmental delay: Frequency estimation & clinical correlation using fluorescence in situ hybridization (FISH

    Directory of Open Access Journals (Sweden)

    Shruthi Mohan

    2016-01-01

    Full Text Available Background & objectives: Subtelomeres are prone to deleterious rearrangements owing to their proximity to unique sequences on the one end and telomeric repetitive sequences, which increase their tendency to recombine, on the other end. These subtelomeric rearrangements resulting in segmental aneusomy are reported to contribute to the aetiology of idiopathic intellectual disability/developmental delay (ID/DD. We undertook this study to estimate the frequency of subtelomeric rearrangements in children with ID/DD. Methods: One hundred and twenty seven children with idiopathic ID/DD were tested for subtelomeric rearrangements using karyotyping and FISH. Blood samples were cultured, harvested, fixed and GTG-banded using the standard protocols. Results: Rearrangements involving the subtelomeres were observed in 7.8 per cent of the tested samples. Detection of rearrangements visible at the resolution of the karyotype constituted 2.3 per cent, while those rearrangements detected only with FISH constituted 5.5 per cent. Five deletions and five unbalanced translocations were detected. Analysis of parental samples wherever possible was informative regarding the inheritance of the rearrangement. Interpretation & conclusions: The frequency of subtelomeric rearrangements observed in this study was within the reported range of 0-35 per cent. All abnormal genotypes were clinically correlated. Further analysis with array technologies presents a future prospect. Our results suggest the need to test individuals with ID/DD for subtelomeric rearrangements using sensitive methods such as FISH.

  15. Subtelomeric rearrangements in Indian children with idiopathic intellectual disability/developmental delay: Frequency estimation & clinical correlation using fluorescence in situ hybridization (FISH)

    Science.gov (United States)

    Mohan, Shruthi; Koshy, Teena; Vekatachalam, Perumal; Nampoothiri, Sheela; Yesodharan, Dhanya; Gowrishankar, Kalpana; Kumar, Jeevan; Ravichandran, Latha; Joseph, Santhosh; Chandrasekaran, Anupama; Paul, Solomon F. D.

    2016-01-01

    Background & objectives: Subtelomeres are prone to deleterious rearrangements owing to their proximity to unique sequences on the one end and telomeric repetitive sequences, which increase their tendency to recombine, on the other end. These subtelomeric rearrangements resulting in segmental aneusomy are reported to contribute to the aetiology of idiopathic intellectual disability/developmental delay (ID/DD). We undertook this study to estimate the frequency of subtelomeric rearrangements in children with ID/DD. Methods: One hundred and twenty seven children with idiopathic ID/DD were tested for subtelomeric rearrangements using karyotyping and FISH. Blood samples were cultured, harvested, fixed and GTG-banded using the standard protocols. Results: Rearrangements involving the subtelomeres were observed in 7.8 per cent of the tested samples. Detection of rearrangements visible at the resolution of the karyotype constituted 2.3 per cent, while those rearrangements detected only with FISH constituted 5.5 per cent. Five deletions and five unbalanced translocations were detected. Analysis of parental samples wherever possible was informative regarding the inheritance of the rearrangement. Interpretation & conclusions: The frequency of subtelomeric rearrangements observed in this study was within the reported range of 0-35 per cent. All abnormal genotypes were clinically correlated. Further analysis with array technologies presents a future prospect. Our results suggest the need to test individuals with ID/DD for subtelomeric rearrangements using sensitive methods such as FISH. PMID:27934799

  16. Potassium accumulation and translocation among rice genotypes in relation to internal potassium use efficiency (IKUE)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Abiotic stresses including potassium deficiency are limiting factors for increasing rice yield. Nine rice genotypes (Oryza Sativa L., indica) differing in sensitivity to low K stress selected from 200 volume-solution screening were used in this study to examine accumulation and translocation of K.

  17. Agrobacterium infection : translocation of virulence proteins and role of VirF in host cells

    NARCIS (Netherlands)

    Jurado Jácome, Esmeralda

    2011-01-01

    The VirB/D4 Type four secretion system (T4SS) is a bacterial multiprotein complex that spans the bacterial envelope, which mediates the translocation of T-DNA and effector virulence proteins into recipient cell. My research revealed that the Agrobacterium VirE3 and VirD2 proteins are effector protei

  18. Effect of honey on bacterial translocation and intestinal morphology in obstructive jaundice

    Institute of Scientific and Technical Information of China (English)

    Cem Gencay; Sibel Serin Kilicoglu; Kemal Kismet; Bulent Kilicoglu; Serap Erel; Sabahattin Muratoglu; Asli Elif Sunay; Esra Erdemli; Mehmet Ali Akkus

    2008-01-01

    AIM:To evaluate the effects of honey on bacterial translocation and intestinal villus histopathology in experimental obstructive jaundice. METHODS:Thirty Wistar-Albino rats were randomly divided into three groups each including 10 animals:group Ⅰ, sham-operated;group Ⅱ,ligation and section of the common bile duct (BDL);group Ⅲ,bile duct ligation followed by oral supplementation of honey (BDL+honey) 10 g/kg per day.Liver, blood,spleen,mesenteric lymph nodes,and ileal samples were taken for microbiological,light and transmission electrone microscopic examination. RESULTS:Although the number of villi per centimeter and the height of the mucosa were higher in sham group,there was no statistically significant difference between sham and BDL+honey groups (P>0.05).On the other hand, there was a statistically significant difference between BDL group and other groups (P0.05).BDL group had significantly higher rates of bacterial translocation as compared with sham and honey groups. Bacterial translocation was predominantly detected in mesenteric lymph nodes. CONCLUSION: Supplementation of honey in presence of obstructive jaundice ameliorates bacterial translocation and improves ileal morphology.

  19. Infectious diseases as main causes of mortality to beavers Castor fiber after translocation to the Netherlands

    NARCIS (Netherlands)

    Nolet, B.A.; Broekhuizen, S.; Dorrestein, G.M.; Rienks, K.M.

    1997-01-01

    Between 1988 and 1994, 58 beavers were translocated from the Elbe region (Germany) to the Netherlands. In 43 animals, radio-transmitters were implanted with a pulse interval which was dependent on body temperature; subsequently, 22 of the released animals were found dead and the cause of death was i

  20. Infectious diseases as main causes of mortality to beavers Castor fiber after translocation to The Netherlands

    NARCIS (Netherlands)

    Nolet, B.A.; Broekhuizen, S.; Dorrestein, G.M.; Rienks, K.M.

    1997-01-01

    Between 1988 and 1994, 58 beavers were translocated from the Elbe region (Germany) to the Netherlands. In 43 animals, radio-transmitters were implanted with a pulse interval which was dependent on body temperature; subsequently, 22 of the released animals were found dead and the cause of death was i

  1. A balanced chromosomal translocation disrupting ARHGEF9 is associated with epilepsy, anxiety, aggression, and mental retardation

    DEFF Research Database (Denmark)

    Kalscheuer, Vera M; Musante, Luciana; Fang, Cheng

    2009-01-01

    Clustering of inhibitory gamma-aminobutyric acid(A) (GABA(A)) and glycine receptors at synapses is thought to involve key interactions between the receptors, a "scaffolding" protein known as gephyrin and the RhoGEF collybistin. We report the identification of a balanced chromosomal translocation ......(A) receptor subtypes involved in epilepsy, anxiety, aggression, insomnia, and learning and memory....

  2. Voltage dependence of Na translocation by the Na/K pump.

    Science.gov (United States)

    Nakao, M; Gadsby, D C

    During each complete reaction cycle, the Na/K pump transports three Na ions out across the cell membrane and two K ions in. The resulting net extrusion of positive charge generates outward membrane current but, until now, it was unclear how that net charge movement occurs. Reasonable possibilities included a single positive charge moving outwards during Na translocation; or a single negative charge moving inwards during K translocation; or either positive or negative charges moving during both translocation steps, but in unequal quantities. Any step that involves net charge movement through the membrane must have voltage-dependent transition rates. Here we report measurements of transient, voltage-dependent, displacement currents generated by the pump when its normal Na/K transport cycle has been interrupted by removal of external K and it is thus constrained to carry out Na/Na exchange. The quantity and voltage sensitivity of the charge moved during these transient currents suggests that Na translocation includes a voltage-dependent transition involving movement of one positive charge across the membrane. This single step can thus fully account for the electrogenic nature of Na/K exchange. The result provides important new insight into the molecular mechanism of active cation transport.

  3. Research methods in weed science: herbicide absorption and translocation in plants using radioisotopes

    Science.gov (United States)

    Herbicide absorption and translocation in plants is a key component in the study of herbicide physiology, mode of action, selectivity, resistance mechanisms, and in the registration process. Radioactive herbicides have been in use for over half-a-century in the research and study of herbicide absorp...

  4. Characterization of partial trisomy 9p due to insertional translocation by chromosomal (micro)FISH

    NARCIS (Netherlands)

    de Pater, JM; Ippel, PF; van Dam, WM; Loneus, WH; Engelen, JJM

    2002-01-01

    We describe a family with an insertion 12;9 translocation occurring in a balanced form in a mother and two sons, but in an unbalanced form in the proband, resulting in trisomy of chromosome region 9p22-->9p24. The proband manifests typical features of trisomy 9p; the clinical signs were mental and g

  5. Bacterial translocation in D-galactosamine-treated rats in a burn model

    NARCIS (Netherlands)

    Dijkstra, HM; Manson, WL; Blaauw, B; Klasen, HJ; deSmet, B

    1996-01-01

    Bacteria and endotoxins can pass through the gut barrier under certain conditions. This process of bacterial translocation (BT) may occur after thermal injury in animals and is thought to play a role in the pathogenesis of septic complications in severely burned patients. The current study was perfo

  6. Translocation of DNA molecules through nanopores with salt gradients: the role of osmotic flow

    NARCIS (Netherlands)

    Hatlo, M.M.; Panja, D.; van Roij, R.

    2011-01-01

    Recent experiments of translocation of double stranded DNA through nanopores M. Wanunu textitet al. Nature Nanotech. 5, 160 (2010) reveal that the DNA capture rate can be significantly influenced by a salt gradient across the pore. We show that osmotic flow combined with electrophoretic effects can

  7. Translocation of DNA Molecules through Nanopores with Salt Gradients: The Role of Osmotic Flow

    NARCIS (Netherlands)

    Hatlo, M. M.; Panja, D.; van Roij, R.H.H.G.

    2011-01-01

    Recent experiments of translocation of double-stranded DNA through nanopores [ M. Wanunu et al. Nature Nanotech. 5 160 (2009)] reveal that the DNA capture rate can be significantly influenced by a salt gradient across the pore. We show that osmotic flow combined with electrophoretic effects can quan

  8. Modelling uptake into roots and subsequent translocation of neutral and ionisable organic compounds

    DEFF Research Database (Denmark)

    Trapp, Stefan

    2000-01-01

    A study on uptake of neutral and dissociating organic compounds from soil solution into roots, and their subsequent translocation, was undertaken using model simulations. The model approach combines the processes of lipophilic sorption, electrochemical interactions, ion trap, advection in xylem a...

  9. Enzymatic evidence for the key role of arginine in nitrogen translocation by arbuscular mycorrhiza fungi

    DEFF Research Database (Denmark)

    Cruz, C.; Egsgaard, Helge; Trujillo, C.;

    2007-01-01

    Key enzymes of the urea cycle and N-15-labeling patterns of arginine (Arg) were measured to elucidate the involvement of Arg in nitrogen translocation by arbuscular mycorrhizal (AM) fungi. Mycorrhiza was established between transformed carrot (Daucus carota) roots and Glomus intraradices in two...

  10. Premodern Translocals: German Merchant Diaspora Between Kalmar and Northern German Towns(1250 – 1500)

    DEFF Research Database (Denmark)

    Naum, Magdalena

    2013-01-01

    of diaspora. This case study also illustrates the importance of engagement with the material world for maintaining such dual relationships and prompts general exploration of theimportance of material culture in diasporic and translocal lives. It discusses how things are used to fill the spaces of physical...

  11. The role of absorption and translocation as a mechanism of resistance to glyphosate

    Science.gov (United States)

    The continuous use of glyphosate has resulted in the selection of resistant biotypes in 13 different species. Three different mechanisms of resistance have been proposed for these biotypes: 1) Decreased translocation to meristems; 2) Mutation of target site (EPSPS) and 3) Increased expression of EP...

  12. Melatonin reduces bacterial translocation and apoptosis in trinitrobenzene sulphonic acid-induced colitis of rats

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    AIM:To investigate the effects of exogenous melatonin on bacterial translocation and apoptosis in a rat ulcerative colitis model.METHODS:Rats were randomly assigned to three groups:group Ⅰ:control,group Ⅱ: experimental colitis,group Ⅲ:colitis plus melatonin treatment.On d 11 after colitis,plasma tumor necrosis factor-α,portal blood endotoxin levels,colon tissue myeloperoxidase and caspase-3 activity were measured.Bacterial translocation was quantified by blood,lymph node,liver and spleen culture.RESULTS:We observed a significantly reduced incidence of bacterial translocation to the liver,spleen,mesenteric lymph nodes,portal and systemic blood in animals treated with melatonin.Treatment with melatonin significantly decreased the caspase-3 activity in colonic tissues compared to that in trinitrobenzene sulphonic acid-treated rats (16.11 ± 2.46 vs 32.97 ± 3.91,P < 0.01).CONCLUSION:Melatonin has a protective effect on bacterial translocation and apoptosis.

  13. Recycling of protein subunits during DNA translocation and cleavage by Type I restriction-modification enzymes.

    Science.gov (United States)

    Simons, Michelle; Szczelkun, Mark D

    2011-09-01

    The Type I restriction-modification enzymes comprise three protein subunits; HsdS and HsdM that form a methyltransferase (MTase) and HsdR that associates with the MTase and catalyses Adenosine-5'-triphosphate (ATP)-dependent DNA translocation and cleavage. Here, we examine whether the MTase and HsdR components can 'turnover' in vitro, i.e. whether they can catalyse translocation and cleavage events on one DNA molecule, dissociate and then re-bind a second DNA molecule. Translocation termination by both EcoKI and EcoR124I leads to HsdR dissociation from linear DNA but not from circular DNA. Following DNA cleavage, the HsdR subunits appear unable to dissociate even though the DNA is linear, suggesting a tight interaction with the cleaved product. The MTases of EcoKI and EcoAI can dissociate from DNA following either translocation or cleavage and can initiate reactions on new DNA molecules as long as free HsdR molecules are available. In contrast, the MTase of EcoR124I does not turnover and additional cleavage of circular DNA is not observed by inclusion of RecBCD, a helicase-nuclease that degrades the linear DNA product resulting from Type I cleavage. Roles for Type I restriction endonuclease subunit dynamics in restriction alleviation in the cell are discussed.

  14. "Reading across Communities" in Biliteracy Practices: Examining Translocal Discourses and Cultural Flows in Literature Discussions

    Science.gov (United States)

    Medina, Carmen

    2010-01-01

    The engagement of immigrant children in literature discussion groups in an elementary school classroom in the United States is studied in this article. The analysis shows how the students' responses are embedded in translocal movements across places, time, and people that can be characterized as constructing dynamic cultural flows. The findings…

  15. MOLECULAR CHARACTERIZATION OF A RECURRING COMPLEX CHROMOSOMAL TRANSLOCATION IN 2 HUMAN EXTRAGONADAL GERM-CELL TUMORS

    NARCIS (Netherlands)

    SINKE, RJ; WEGHUIS, DO; SUIJKERBUIJK, RF; TANIGAMI, A; NAKAMURA, Y; LARSSON, C; WEBER, G; DEJONG, B; OOSTERHUIS, JW; MOLENAAR, WM; VANKESSEL, AG

    1994-01-01

    The molecular characterization of a recurring complex chromosomal translocation involving 6p21, 6p22, 6p23, and 11q13 in two independent bur similar extragonadal human germ cell rumors was initiated using fluorescence in situ hybridization (FISH) and pulse field gel electrophoresis (PFGE) techniques

  16. Molecular characterization of a recurring complex chromosomal translocation in two human extragonadal germ cell tumors.

    NARCIS (Netherlands)

    Sinke, R J; Weghuis, D O; Suijkerbuijk, R F; Tanigami, A; Nakamura, Y; Larsson, C; Weber, G; Jong, B de; Oosterhuis, J W; Molenaar, W M

    1994-01-01

    The molecular characterization of a recurring complex chromosomal translocation involving 6p21, 6p22, 6q23, and 11q13 in two independent but similar extragonadal human germ cell tumors was initiated using fluorescence in situ hybridization (FISH) and pulse field gel electrophoresis (PFGE) techniques

  17. Saethre-Chotzen syndrome with familial translocation at chromosome 7p22.

    Science.gov (United States)

    Reid, C S; McMorrow, L E; McDonald-McGinn, D M; Grace, K J; Ramos, F J; Zackai, E H; Cohen, M M; Jabs, E W

    1993-10-01

    Chromosome analysis of a male infant and his mother with Saethre-Chotzen syndrome demonstrated an apparently balanced translocation, t(2;7)(p23;p22). This association lends support to localization of the gene for Saethre-Chotzen syndrome to the 7p2 region and supports further involvement of gene(s) in the 7p22 region.

  18. Sustainable Development Mechanism of Food Culture’s Translocal Production Based on Authenticity

    Directory of Open Access Journals (Sweden)

    Guojun Zeng

    2014-10-01

    Full Text Available Food culture is a kind of non-material culture with authenticity. To achieve sustainable development of translocal heritage and food culture, we must protect its authenticity. By selecting the cases of the Dongbeiren Flavor Dumpling Restaurant and the Daozanjia Northeast Dumpling Restaurant and using the in-depth interview method, this study discusses how northeastern Cuisine in Guangzhou balances the inheritance and innovation of authenticity, how producers and customers negotiate, and how to realize sustainable development. The main conclusions are: first, there are two different paths of translocal food culture production, which are “authentic food culture production” and “differentiated food culture production”. Second, what translocal enterprises produce is not objective authenticity, but constructive authenticity, or even existential authenticity. Third, compared with differentiated food culture production, authentic food culture production is helpful for the sustainable development of local food culture production. It protects the locality while transmitting and developing the local culture. Fourth, translocal food culture production is a process in which the producers and consumers continue to interact to maintain a state of equilibrium, which informs the sustainable development mechanism with a high degree of authenticity.

  19. Effects of lactulose on intestinal endotoxin and bacterial translocation in cirrhotic rats

    Institute of Scientific and Technical Information of China (English)

    张顺财; 王唯; 任卫英; 戴茜; 贺伯明; 周康

    2003-01-01

    Objective To investigate the effects of lactulose on intestinal bacterial overgrowth (IBO), bacterial translocation (BT), intestinal transit and permeability in cirrhotic rats. Methods BT in all animals was assessed by bacterial culture of mesenteric lymph node (MLN), liver and spleen, and IBO was assessed by a jejunal bacterial count of the specific organism. Intestinal permeability was determined by the 24-hour urinary 99mTc-diethylenetriaminepentaacetate (99mTc-DTPA) excretion, and intestinal transit was determined by measuring the distribution of 51 Cr in the intestine. Results BT and IBO were found in 48% and 80% of the cirrhotic rats, respectively, while not in the control rats. Cirrhotic rats with IBO had significantly higher levels of intestinal endotoxin higher rates of bacterial translocation, shorter intestinal transit time and higher intestinal permeability than those without IBO. It was also found that BT was closely associated with IBO and injury of the intestinal barrier. Compared with the placebo group, lactulose-treated rats had lower rates of BT and IBO, which was closely associated with increased intestinal transit and improved intestinal permeability by lactulose. Conclusions Our study indicate that endotoxin and bacterial translocation in cirrhotic rats may attribute to IBO and increased intestinal permeability. Lactulose that accelerates intestinal transit and improves intestinal permeability might be helpful in preventing intestinal bacterial and endotoxin translocation.

  20. NRT/PTR transporters are essential for translocation of glucosinolate defence compounds to seeds

    DEFF Research Database (Denmark)

    Nour-Eldin, Hussam Hassan; Andersen, Tonni Grube; Burow, Meike;

    2012-01-01

    In plants, transport processes are important for the reallocation of defence compounds to protect tissues of high value, as demonstrated in the plant model Arabidopsis, in which the major defence compounds, glucosinolates, are translocated to seeds on maturation. The molecular basis for long-dist...