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Sample records for rodent experiment pare

  1. Defectos de la pared abdominal

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    Adis L. Peña Cedeño

    2004-03-01

    Full Text Available Se realizó un estudio de los fetos con malformaciones congénitas, dadas por defecto de la pared abdominal (DPA, nacidos en el Hospital Universitario Ginecoobstétrico de Guanabacoa durante los años 1984 al 2000, para determinar la frecuencia de los distintos tipos de defectos de la pared abdominal y las malformaciones asociadas a éstas. Se revisaron los protocolos de necropsias e historias clínicas en este período y se obtuvieron 25 casos con DPA. La malformación más frecuente fue el onfalocele con 14 casos, seguido de la gastrosquisis con 6 casos. Se hallaron malformaciones asociadas en el 68 % de los casos, y se comprobó la efectividad del Programa Nacional de Malformaciones Congénitas, pues en el 80 % de las pacientes se interrumpió precozmente el embarazo.A study of the fetuses with congenital malformations due to defect of the abdominal wall (AWD that were born at the Gynecoobstetric Teaching Hospital of Guanabacoa from 1984 to 2000 was conducted aimed at determining the frequency of the different types of defects of the abdominal wall and the malformations associated with them. The protocosl of necropsies and medical histories corresponding to this period were reviewed and 25 cases with AWD were detected. The most common malformation was omphalocele with 14 cases, followed by gastrosquisis with 6 cases. Associated malformations were found in 68 % of the cases and it was proved the effectiveness of the National Program of Congenital Malformations, since pregnancy was interrupted early in 80 % of the patients.

  2. Sexual Experience in Female Rodents: Cellular Mechanisms and Functional Consequences

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    Meisel, Robert L.; Mullins, Amanda J.

    2007-01-01

    The neurobiology of female sexual behavior has largely focused on mechanisms of hormone action on nerve cells and how these effects translate into the display of copulatory motor patterns. Of equal importance, though less studied, are some of the consequences of engaging in sexual behavior, including the rewarding properties of sexual interactions and how sexual experience alters copulatory efficiency. This review summarizes the effects of sexual experience on reward processes and copulation in female Syrian hamsters. Neural correlates of these sexual interactions include long-term cellular changes in dopamine transmission and postsynaptic signaling pathways related to neuronal plasticity (e.g., dendritic spine formation). Taken together, these studies suggest that sexual experience enhances the reinforcing properties of sexual behavior, which has the coincident outcome of increasing copulatory efficiency in a way that can increase reproductive success. PMID:16978593

  3. SEKOLAH TINGGI ASTRONOMI DI KOTA PARE-PARE TEMA ARSITEKTUR METAFORA

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    Shahibuddin Juddah

    2015-06-01

    Full Text Available Abstrak— Kota Pare-Pare sebagai kota yang layak memiliki suatu fasilitas ilmu pengetahuan dan teknologi yang diperuntukkan bagi generasi-generasi muda penerus bangsa di kota Pare-Pare dalam hal ini fasilitas ilmu pengetahuan dan teknologi yang berkaitan dengan astronomi yakni Sekolah Tinggi Astronomi (Ilmu Perbintangan di Kota Pare-pare dengan tema Arsitektur Metafora. Pada bidang astronomi terdapat berbagai macam bentuk-bentuk fantastis yang dapat dijadikan lambang bentuk dalam arsitektur seperti bentuk rasi bintang, bentuk lintasan orbit planet dan bentuk-bentuk benda langit lainnya, begitu juga dengan bentuk-bentuk fenomena yang dihasilkannya. Dengan perwujudan bentuk-bentuk ini sebagai simbol pada gaya bangunan, baik bentuk bangunan, fungsi maupun penataan ruang di dalamnya, diharapkan pelaku kegiatan dalam bangunan merasakan maksud dan ekspresi dari bangunan. Kata Kunci : Sekolah Tinggi, Astronomi, Arsitektur Metafora Abstract—Pare- Pare as a city that deserves to have a facility of science and technology that is intended for younger generations in Pare - Pare in this case the facilities of science and technology relates to astronomy namely the College of Astronomy (Science Astrology in Pare- pare the theme of Architecture Metaphor. In the field of astronomy there are various kinds of fantastic shapes that can be used as the epitome of form in architecture such as the shape of constellations, planets orbit trajectory shapes and forms of other celestial bodies, as well as the forms of the phenomenon produces. The realization of these forms as a symbol on the style of the building, both buildings form, function and arrangement of space in it, it is hoped the perpetrators of activity in the building feel the intention and expression of the building Key word : High School, Astronomy, Metaphor Architecture

  4. Environmental degradation and intra-household welfare: the case of the Tanzanian rural South Pare Highlands

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    Dimoso, R.L.

    2009-01-01

    Key words: Environmental degradation, intrahousehold labour allocation, intrahousehold welfare.
    Rural south Pare highlands in Tanzania experience a deteriorating environmental situation. Of particular importance is the disappearance of forests and woodlands. The consequence are declining

  5. Importance of rodents for hydrology: lessons learnt from various field experiments

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    van Schaik, Loes; Zangerlé, Anne; Schneider, Anne-Kathrin; Schröder, Boris; Eccard, Jana

    2017-04-01

    organisms are known to create soil macropores of different sizes and with varying extent and orientation: most commonly earthworms, rodents, moles and roots. Preferential flow through macropore networks is dynamic and typically occurs when short individual macropores become connected at the hillslope scale as the nodes between the macropores become wet. Large lateral macropores may contribute to rapid subsurface stormflow of water and solutes at hillslope scale and supply a significant part of the catchment scale discharge during high intensity rainfall events even under relatively dry catchment state. Outflow from soil pipes, especially in the valley bottom or along the banking near to streams, is frequently observed, however, it remains a challenge to measure the spatial distribution, extent and connectivity of macropores at hill slope scales. We hypothesize that local information on organism abundances may be used as an indicator for spatial variability in infiltration, water storage and fluxes at the small scale and that knowledge on the landscape scale spatial distribution of organisms can provide information on connectivity of macropores at hillslope scale. Here we summarize the lessons learnt during three years of measurements aimed at determining the influence of rodent burrows on soil hydrology in a meso-scale catchment. Within the Attert Catchment (297 km2) in Luxembourg we performed sprinkling experiments with a brilliant blue tracer on twelve plots, of which six directly above rodent burrow openings and six on a surface without a rodent burrow opening, in order to examine the influence of the burrow openings on the infiltration pattern. Then we tested the extent of flow through mice burrows in different forest types, with varying geology and slope, by supplying 5 Liters of water with brilliant blue tracer directly to 24 burrow openings at soil surface. We excavated the burrows to measure how far the water was transported laterally in the burrow. Though

  6. Effects of early life adverse experiences on brain activity: Implications from maternal separation models in rodents

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    Mayumi eNishi

    2014-06-01

    Full Text Available During postnatal development, adverse early life experiences can affect the formation of neuronal circuits and exert long-lasting influences on neural function. Many studies have shown that daily repeated MS, an animal model of early life stress, can modulate the hypothalamic-pituitary-adrenal axis (HPA axis and can affect subsequent brain function and emotional behavior during adulthood. However, the molecular basis of the long-lasting effects of early life stress on brain function has not been completely elucidated. In this review, we introduce various cases of MS in rodents and illustrate the alterations in HPA axis activity by focusing on corticosterone (CORT, an end product of the HPA axis in rodents. We then present a characterization of the brain regions affected by various patterns of MS, including repeated MS and single time MS at various stages before weaning, by investigating c-Fos expression, a biological marker of neuronal activity. These CORT and c-Fos studies suggest that repeated early life stress may affect neuronal function in region- and temporal-specific manners, indicating a critical period for habituation to early life stress. Next, we discuss how early life stress can impact behavior, namely by inducing depression, anxiety or eating disorders. Furthermore, alterations in gene expression in adult mice exposed to MS, especially epigenetic changes of DNA methylation, are discussed.

  7. Maximizing Science Return from Future Rodent Experiments on the International Space Station (ISS): Tissue Preservation

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    Choi, S. Y.; Lai, S.; Klotz, R.; Popova, Y.; Chakravarty, K.; Beegle, J. E.; Wigley, C. L.; Globus, R. K.

    2014-01-01

    To better understand how mammals adapt to long duration habitation in space, a system for performing rodent experiments on the ISS is under development; Rodent Research-1 is the first flight and will include validation of both on-orbit animal support and tissue preservation. To evaluate plans for on-orbit sample dissection and preservation, we simulated conditions for euthanasia, tissue dissection, and prolonged sample storage on the ISS, and we also developed methods for post-flight dissection and recovery of high quality RNA from multiple tissues following prolonged storage in situ for future science. Mouse livers and spleens were harvested under conditions that simulated nominal, on-orbit euthanasia and dissection operations including storage at -80 C for 4 months. The RNA recovered was of high quality (RNA Integrity Number, RIN(is) greater than 8) and quantity, and the liver enzyme contents and activities (catalase, glutathione reductase, GAPDH) were similar to positive controls, which were collected under standard laboratory conditions. We also assessed the impact of possible delayed on-orbit dissection scenarios (off-nominal) by dissecting and preserving the spleen (RNAlater) and liver (fast-freezing) at various time points post-euthanasia (from 5 min up to 105 min). The RNA recovered was of high quality (spleen, RIN (is) greater than 8; liver, RIN (is) greater than 6) and liver enzyme activities were similar to positive controls at all time points, although an apparent decline in select enzyme activities was evident at the latest time (105 min). Additionally, various tissues were harvested from either intact or partially dissected, frozen carcasses after storage for approximately 2 months; most of the tissues (brain, heart, kidney, eye, adrenal glands and muscle) were of acceptable RNA quality for science return, whereas some tissues (small intestine, bone marrow and bones) were not. These data demonstrate: 1) The protocols developed for future flight

  8. Strategic Style in Pared-Down Poker

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    Burns, Kevin

    This chapter deals with the manner of making diagnoses and decisions, called strategic style, in a gambling game called Pared-down Poker. The approach treats style as a mental mode in which choices are constrained by expected utilities. The focus is on two classes of utility, i.e., money and effort, and how cognitive styles compare to normative strategies in optimizing these utilities. The insights are applied to real-world concerns like managing the war against terror networks and assessing the risks of system failures. After "Introducing the Interactions" involved in playing poker, the contents are arranged in four sections, as follows. "Underpinnings of Utility" outlines four classes of utility and highlights the differences between them: economic utility (money), ergonomic utility (effort), informatic utility (knowledge), and aesthetic utility (pleasure). "Inference and Investment" dissects the cognitive challenges of playing poker and relates them to real-world situations of business and war, where the key tasks are inference (of cards in poker, or strength in war) and investment (of chips in poker, or force in war) to maximize expected utility. "Strategies and Styles" presents normative (optimal) approaches to inference and investment, and compares them to cognitive heuristics by which people play poker--focusing on Bayesian methods and how they differ from human styles. The normative strategy is then pitted against cognitive styles in head-to-head tournaments, and tournaments are also held between different styles. The results show that style is ergonomically efficient and economically effective, i.e., style is smart. "Applying the Analysis" explores how style spaces, of the sort used to model individual behavior in Pared-down Poker, might also be applied to real-world problems where organizations evolve in terror networks and accidents arise from system failures.

  9. Laser welding of vas deferens in rodents: initial experience with fluid solders.

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    Trickett, R I; Wang, D; Maitz, P; Lanzetta, M; Owen, E R

    1998-01-01

    This study evaluates the use of sutureless laser welding for vasovasostomy. In 14 rodents, the left vas deferens underwent vasovasostomy using an albumin-based solder applied to the adventitia of the vas deferens. The solder contained the dye, indocyanine green, to allow selective absorption and denaturation by a fiber-coupled 800-nm diode laser. The right vas deferens served as a control, receiving conventional layered microsurgical repair. We used a removable 4/0 nylon stent and microclamps to appose the vas deferens during repair, with no need for stay sutures. The mean time to perform laser solder repair (23.5 min) and conventional repair (23.3 min) were not significantly different (P=0.91). However, examination after 8 weeks showed that granuloma formation (G) and patency (P) rates for the conventional suture technique (G, 14%; P, 93%) were significantly better than observed for the laser solder technique (G, 57%; P, 50%).

  10. Experiment K-7-29: Connective Tissue Studies. Part 3; Rodent Tissue Repair: Skeletal Muscle

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    Stauber, W.; Fritz, V. K.; Burkovskaya, T. E.; Ilyina-Kakueva, E. I.

    1994-01-01

    Myofiber injury-repair was studied in the rat gastrocnemius following a crush injury to the lower leg prior to flight in order to understand if the regenerative responses of muscles are altered by the lack of gravitational forces during Cosmos 2044 flight. After 14 days of flight, the gastrocnemius muscle was removed from the 5 injured flight rodents and various Earth-based treatment groups for comparison. The Earth-based animals consisted of three groups of five rats with injured muscles from a simulated, tail-suspended, and vivarium as well as an uninjured basal group. The gastrocnemius muscle from each was evaluated by histochemical and immunohistochemical techniques to document myofiber, vascular, and connective tissue alterations following injury. In general the repair process was somewhat similar in all injured muscle samples with regard to extracellular matrix organization and myofiber regeneration. Small and large myofibers were present with a newly organized extracellular matrix indicative of myogenesis and muscle regeneration. In the tail-suspended animals, a more complete repair was observed with no enlarged area of non-muscle cells or matrix material visible. In contrast, the muscle samples from the flight animals were less well differentiated with more macrophages and blood vessels in the repair region but small myofibers and proteoglycans, nevertheless, were in their usual configuration. Thus, myofiber repair did vary in muscles from the different groups, but for the most part, resulted in functional muscle tissue.

  11. Experiential Learning in Rodents: Past Experience Enables Rapid Learning and Localized Encoding in Hippocampus

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    Cox, Conor D.; Palmer, Linda C.; Pham, Danielle T.; Trieu, Brian H.; Gall, Christine M.; Lynch, Gary

    2017-01-01

    Humans routinely use past experience with complexity to deal with novel, challenging circumstances. This fundamental aspect of real-world behavior has received surprisingly little attention in animal studies, and the underlying brain mechanisms are unknown. The present experiments tested for transfer from past experience in rats and then used…

  12. A protein domain interaction interface database: InterPare

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    Lee Jungsul

    2005-08-01

    Full Text Available Abstract Background Most proteins function by interacting with other molecules. Their interaction interfaces are highly conserved throughout evolution to avoid undesirable interactions that lead to fatal disorders in cells. Rational drug discovery includes computational methods to identify the interaction sites of lead compounds to the target molecules. Identifying and classifying protein interaction interfaces on a large scale can help researchers discover drug targets more efficiently. Description We introduce a large-scale protein domain interaction interface database called InterPare http://interpare.net. It contains both inter-chain (between chains interfaces and intra-chain (within chain interfaces. InterPare uses three methods to detect interfaces: 1 the geometric distance method for checking the distance between atoms that belong to different domains, 2 Accessible Surface Area (ASA, a method for detecting the buried region of a protein that is detached from a solvent when forming multimers or complexes, and 3 the Voronoi diagram, a computational geometry method that uses a mathematical definition of interface regions. InterPare includes visualization tools to display protein interior, surface, and interaction interfaces. It also provides statistics such as the amino acid propensities of queried protein according to its interior, surface, and interface region. The atom coordinates that belong to interface, surface, and interior regions can be downloaded from the website. Conclusion InterPare is an open and public database server for protein interaction interface information. It contains the large-scale interface data for proteins whose 3D-structures are known. As of November 2004, there were 10,583 (Geometric distance, 10,431 (ASA, and 11,010 (Voronoi diagram entries in the Protein Data Bank (PDB containing interfaces, according to the above three methods. In the case of the geometric distance method, there are 31,620 inter-chain domain

  13. Identification of Conflicting Questions in the PARES System

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    Avgoustos Tsinakos

    2012-06-01

    Full Text Available Student testing and knowledge assessment is a significant aspect of the learning process. In a number of cases, it is expedient not to present the exact same test to all learners all the time (Pritchett, 1999. This may be desired so that cheating in the exam is made harder to carry out or so that the learners can take several practice tests on the same subject as part of the course.This study presents an e-testing platform, namely PARES, which aims to provide assessment services to academic staff by facilitating the creation and management of question banks and powering the delivery of nondeterministically generated test suites. PARES uses a conflict detection algorithm based on the vector space model to compute the similarity between questions and exclude questions which are deemed to have an unacceptably large similarity from appearing in the same test suite. The conflict detection algorithm and a statistical evaluation of its accuracy are presented. Evaluation results show that PARES succeeds in detecting question types at about 90% and its efficiency can be further increased through continuing education and enrichment of the system’s correlation vocabulary.

  14. Costs of coexistence along a gradient of competitor densities: an experiment with arvicoline rodents.

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    Eccard, Jana A; Ylönen, Hannu

    2007-01-01

    1. Costs of coexistence for species with indirect resource competition usually increase monotonically with competitor numbers. Very little is known though about the shape of the cost function for species with direct interference competition. 2. Here we report the results of an experiment with two vole species in artificial coexistence in large enclosures, where density of the dominant competitor species (Microtus agrestis) was manipulated. Experimental populations of the subordinate vole species (Clethrionomys glareolus) were composed of same aged individuals to study distribution of costs of coexistence with a dominant species within an age-cohort. 3. Survival and space use decreased gradually with increasing field vole numbers. Thus, responses to interference competition in our system appeared to be similar as expected from resource competition. The total number of breeders was stable. Reproductive characteristics such as the timing of breeding, and the litter size were not affected. In the single species enclosures a proportion of surviving individuals were not able to establish a breeding territory against stronger conspecifics. Under competition with heterospecifics such nonbreeders suffered high mortality, whereas the breeders survived. 4. Combined interference of dominant conspecifics and heterospecifics probably increased the frequency of aggressive interactions, social stress and mortality for the weaker individuals within a homogeneous age cohort of the subordinate competitor population. 5. Our results suggest, that in open systems where bank voles are outcompeted over the breeding season by faster reproducing field voles, animals able to establish a territory may be able to withstand competitor pressure, while nonbreeding bank vole individuals are forced to emigrate to suboptimal forest habitats.

  15. Evaluación externa: características y vivencias del equipo de pares

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    Quesada Pacheco, Allen

    2006-08-01

    Full Text Available Resumen: La Evaluación Externa es la fase que sigue a la Autoevaluación de programas académicos a nivel superior. Este proceso consiste en constatar y validar, desde la perspectiva externa, cómo se sitúa el programa evaluado respecto al modelo de evaluación, tanto a través de un análisis documental, como a través de una visita. Este artículo se centra particularmente en la validación externa de programas académicos de acuerdo a los lineamientos del Sistema Centroamericano de Evaluación y Acreditación de la Educación Superior (SICEVAES.Analiza el papel de los pares externos, sus compromisos y responsabilidades. Se describen las etapas del desarrollo de la vista por el equipo de pares y comparte aportaciones significativas del equipo de pares durante la realización de la visita como insumo enriquecedor al proceso de evaluación externa.Abstract:The External Evaluation is the phase that follows the self-evaluation of programs or institutions at the university level. This process verifies and validates, from an external perspective, the real scenario of the study program or faculty unit that has undergone a self-evaluation process regarding the evaluation model utilized, through an analysis of documents and through an on-site visit. The main concern of this article is on the external evaluation of study programs based on the regulations of the Central American System for Evaluation and Accreditation of Higher Education. This paper analyzes the role, obligations and responsibilities of members of the evaluation group. It describes the stages for the development of the visit and shares significant on-site experiences that can enrich the external evaluation process.

  16. Grupos áulicos: aprendendo com os pares

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    Nair Cristina da Silva Tuboiti

    Full Text Available Resumo:Este estudo visa evidenciar as contribuições dos grupos áulicos no processo de aprendizagem entre pares. Pressupõe-se que grupos áulicos garantem o espaço relacional na perspectiva multidirecional. A coleta de dados foi realizada em uma turma de 1º ano do Ensino Fundamental de uma escola pública de Samambaia, Distrito Federal, por meio de observação participante, entrevista não estruturada e análise documental. Os dados foram analisados na perspectiva sociocultural em diálogo com a teoria interpretativa de Geertz. Os resultados indicam que os grupos áulicos permitem reorganizar o pensamento fazendo diferença no campo do ensino e aprendizagem, na perspectiva de um espaço que possibilite a diversidade de relações, rompendo com as profecias de fracasso e instaurando um lugar real do aluno nessa relação de construção de conhecimentos. A interlocução entre os pares ocorre no grupo heterogêneo que possibilita que se aprendam conceitos com os diferentes saberes, afinal aprende-se em meio à diversidade.

  17. UJI POTENSI ANTIPLASMODIUM EKSTRAK BUAH PARE (Momordica charantia L. TERHADAP Plasmodium falcifarum

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    Susilawati

    2014-05-01

    Full Text Available Malaria masih menjadi salah satu penyakit endemis dan masalah kesehatan utama di Indonesia. Buah pare (Momordica charantia L. secara tradisional sering digunakan sebagai obat. Tujuan dari penelitian ini adalah untuk menguji potensi antiplasmodium in vitro ekstrak buah pare terhadap Palsmodium falciparum sehingga dapat digunakan sebagai obat anti malaria. Buah pare diekstrak dengan metode maserasi menggunakan pelarut metanol. Uji aktivitas antiplasmodium dilakukan secara pengamatan mikroskopik pada kultur strain P. falcifarum 3D7. Berdasarkan hasil pengujian, sampel ekstrak metanol buah pare memiliki aktivitas penghambatan terhadap pertumbuhan parasit P. falciparum 3D7. Kekuatan aktivitas antimalaria dengan nilai IC50 = 0,39 µg/mL.

  18. Tannin concentration enhances seed caching by scatter-hoarding rodents: An experiment using artificial ‘seeds’

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    Wang, Bo; Chen, Jin

    2008-11-01

    Tannins are very common among plant seeds but their effects on the fate of seeds, for example, via mediation of the feeding preferences of scatter-hoarding rodents, are poorly understood. In this study, we created a series of artificial 'seeds' that only differed in tannin concentration and the type of tannin, and placed them in a pine forest in the Shangri-La Alpine Botanical Garden, Yunnan Province of China. Two rodent species ( Apodemus latronum and A. chevrieri) showed significant preferences for 'seeds' with different tannin concentrations. A significantly higher proportion of seeds with low tannin concentration were consumed in situ compared with seeds with a higher tannin concentration. Meanwhile, the tannin concentration was significantly positively correlated with the proportion of seeds cached. The different types of tannin (hydrolysable tannin vs condensed tannin) did not differ significantly in their effect on the proportion of seeds eaten in situ vs seeds cached. Tannin concentrations had no significant effect on the distance that cached seeds were carried, which suggests that rodents may respond to different seed traits in deciding whether or not to cache seeds and how far they will transport seeds.

  19. PENGARUH INFUS BUAH PARE (Momordica charantia L TERHADAP KELENJAR PROSTAT TIKUS PUTIH

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    M. Wien Winarno

    2012-10-01

    Full Text Available Buah pare (Momordica charantia L.. selain dikenal sebagai sayuran juga digunakan sebagai obat tradisional. Beberapa hasil penelitian menyimpulkan bahwa perasan buah pare dapat menurunkan kadar glukosa darah. Sebagai kontrasepsi pria, buah pare terbukti menyebabkan abnormalitas struktur morfologi sperma dan menurunkan kadar testosteron darah. Ekstrak buah pare secara invitro menghambat pertumbuhan sel-sel kanker prostat. Buah pare mengandung momordisin, momordin, asam resinal dan sterol. Berdasarkan efeknya yaitu dapat menurunkan hormon testosteron, dan secara invitro menghambat sel-sel kanker prostat dan adanya kandungan sterol, maka dilakukan penelitian Pengaruh infus buah pare (M. charantia L. terhadap kelenjar prostat tikus putih. Penelitian menggunakan hewan coba tikus putih, galur Wistar dengan bobot badan 180-200 gram. Rancangan penelitian yang digunakan "Rancangan Acak Lengkap". Bahan yang diteliti berupa infus buah pare dengan dosis pemberian 625 mg, 1250 mg, 2500 mg dan 5000 mg/kg bb. Sebagai pembanding digunakan akuades. Bahan diberikan secara oral, satu kali sehari selama 30 hari. Hari ke-31 hewan dibunuh, diambil kelenjar prostatnya untuk dibuat preparat histopatologi. Pengamatan meliputi berat dan ketebalan sel epitel kelenjar prostat. Hasilnya, pemberian infus buah pare pada semua dasis dibandingkan dengan akuades (kontrol berpengaruh sangat nyata (P<0,01 terhadap berat kelenjar prostat. Sementara infus buah pare dosis 2500 mg/kg bb. berpengaruh sangat nyata (P<0,01 terhadap tebal set epitel kelenjar prostat. Dengan demikian dapat disimpulkan bahwa infus buah pare dapat menurunkan berat kelenjar prostat normal dan menipiskan sel epitel dari kelenjar prostat.   Kata kunci : pare, Momordica charantia L., kelenjar prostat

  20. Learning Outcomes and School Cost-Effectiveness in Mexico: The PARE Program. Policy Research Working Papers.

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    Acevedo, Gladys Lopez

    This paper examines the impact on student learning of the Programa para Abatir el Rezago Educativo (PARE), which aimed to improve the quality and efficiency of primary education in four Mexican states by increasing school resources. PARE was implemented in the states of Oaxaca, Guerrero, Chiapas, and Hidalgo, which have the highest incidence of…

  1. NASA's Rodent Research Project: Validation of Flight Hardware, Operations and Science Capabilities for Conducting Long Duration Experiments in Space

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    Choi, S. Y.; Beegle, J. E.; Wigley, C. L.; Pletcher, D.; Globus, R. K.

    2015-01-01

    Research using rodents is an essential tool for advancing biomedical research on Earth and in space. Rodent Research (RR)-1 was conducted to validate flight hardware, operations, and science capabilities that were developed at the NASA Ames Research Center. Twenty C57BL/6J adult female mice were launched on Sept 21, 2014 in a Dragon Capsule (SpaceX-4), then transferred to the ISS for a total time of 21-22 days (10 commercial mice) or 37 (10 validation mice). Tissues collected on-orbit were either rapidly frozen or preserved in RNA later at less than or equal to -80 C (n=2/group) until their return to Earth. Remaining carcasses were rapidly frozen for dissection post-flight. The three controls groups at Kennedy Space Center consisted of: Basal mice euthanized at the time of launch, Vivarium controls, housed in standard cages, and Ground Controls (GC), housed in flight hardware within an environmental chamber. FLT mice appeared more physically active on-orbit than GC, and behavior analysis are in progress. Upon return to Earth, there were no differences in body weights between FLT and GC at the end of the 37 days in space. RNA was of high quality (RIN greater than 8.5). Liver enzyme activity levels of FLT mice and all control mice were similar in magnitude to those of the samples that were optimally processed in the laboratory. Liver samples collected from the intact frozen FLT carcasses had RNA RIN of 7.27 +/- 0.52, which was lower than that of the samples processed on-orbit, but similar to those obtained from the control group intact carcasses. Nonetheless, the RNA samples from the intact carcasses were acceptable for the most demanding transcriptomic analyses. Adrenal glands, thymus and spleen (organs associated with stress response) showed no significant difference in weights between FLT and GC. Enzymatic activity was also not significantly different. Over 3,000 tissues collected from the four groups of mice have become available for the Biospecimen Sharing

  2. Pola Komunikasi Antara Pedagang dan Pembeli di Desa Pare, Kampung Inggris Kediri

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    Suzy Azeharie

    2015-12-01

    Full Text Available This study will examine the patterns of communication used between merchants with shoppers, teachers and students, as well as in rural communities or village English Pare Kediri regency in East Java. Methodology used is a qualitative methodology with data collection through interviews, direct observation Pare village, and through the study of literature. The theories used are the theory of verbal and nonverbal communication, interpersonal communication, the theory of acculturation and assimilation of culture. The conclusion from this study is the communication patterns merchants with shoppers, teachers and students, as well as in rural communities Pare take place in the primary, which means face to face and in English. Basic English Course in operation since 1976 turned out to be a big impact in the lives of people in the village, such changes include the shift of the livelihoods of residents who are traditionally farmers have become the owner of an English language course, rent boarding houses, kiosks drinks and food, open rental bike, copy, etc. Penelitian ini akan mengupas mengenai pola komunikasi yang digunakan antara pedagang dengan pembeli, guru dengan siswa, serta komunitas masyarakat di desa Pare atau kampung Inggris Kabupaten Kediri Jawa Timur. Metodelogi yang digunakan adalah metodologi kualitatif dengan teknik pengumpulan data melalui wawancara, observasi langsung ke desa Pare, dan melalui studi literatur. Teori-teori yang digunakan adalah teori komunikasi verbal dan non verbal, komunikasi interpersonal, teori akulturasi dan asimilasi budaya. Kesimpulan dari penelitian ini adalah pola komunikasi pedagang dengan pembeli, guru dengan siswa, serta komunitas masyarakat di desa Pare berlangsung secara primer, artinya bertatap muka dan menggunakan bahasa Inggris. Basic English Course yang beroperasi sejak tahun 1976 ternyata membawa pengaruh besar dalam kehidupan masyarakat di desa tersebut, perubahan tersebut antara lain beralihnya mata

  3. Padres, profesores y pares: contribuciones para la autoestima y coping en los adolescentes

    Directory of Open Access Journals (Sweden)

    Catarina Pinheiro Mota

    2014-05-01

    Full Text Available En consonancia con la teoría del apego, la calidad de la relación con figuras significativas juegan un papel clave en el desarrollo psicosocial, contribuyendo, entre otras cosas, para el desarrollo de la autoestima y estrategias de coping. El objetivo de este estudio es determinar la contribución diferencial de variables relacionales (incluidas las relaciones con los padres, pares y profesores en la predicción de la autoestima y coping en una muestra de 216 adolescentes, entre 14 y 16 años y de ambos sexos. El apego a los padres, las relaciones con los pares y con profesores revelaron diferentes configuraciones de las variables en la explicación de la autoestima y coping. La autoestima es positivamente predicha por la calidad de lazo emocional y negativamente por la inhibición de la exploración y la individualidad en la vinculación a los padres. El coping activo es positivamente predicho por la autoestima y la relación a los pares. Se observó un efecto positivo e indirecto de la calidad del lazo emocional en el coping activo a través de la autoestima y la relación a los pares. La relación con los pares parece ser mejorada por la calidad de la relación con los profesores. Los resultados serán discutidos en función de la teoría del apego y de acuerdo con una perspectiva ecológica del desarrollo.

  4. Constraints to peer scaffolding Limitações na colaboração entre pares

    Directory of Open Access Journals (Sweden)

    Marília Mendes Ferreira

    2008-06-01

    Full Text Available Several studies, usually carried out in settings that are conducive to interaction, demonstrate peers can provide mutual scaffolding effectively. In contrast, this article focuses on constraints to peer scaffolding which, possibly, happened because of participants' demotivating learning environment. Analysis is based on the video and audio recordings of the performance of two beginning Brazilian students carrying out two oral tasks in an EFL class. Task one consists of an information gap and task two, of a communicative drill. The following constraints were identified: 1 the less capable peer's object-regulation, 2 the more capable peer's hindrance to scaffolding, 3 the more capable peer's lack of L2 knowledge. These hindrances can be explained by the students' pervasive and frustrating foreign language learning experience in the Brazilian public school and by the lack of socialization into scaffolding.Vários estudos, geralmente conduzidos em ambientes que favorecem a interação, mostram que colegas podem colaborar mutuamente e de modo eficaz. Entretanto, este trabalho aborda obstáculos à criação desse tipo de andaime que podem ter ocorrido devido ao ambiente desmotivador dos alunos utilizados na pesquisa. A análise é baseada em gravações de áudio e vídeo do desempenho dos alunos em duas atividades orais em uma aula de inglês como língua estrangeira. A atividade um consistiu em uma lacuna de informação e a dois, em um drill comunicativo. Os seguintes obstáculos foram encontrados: 1 a regulação pelo objeto do aluno menos capaz, 2 dificuldades do aluno mais capaz em promover andaimes, 3 falta de conhecimento de inglês do aluno mais capaz. Esses empecilhos podem ser explicados pela experiência onipresente e frustrante desses alunos em aprender inglês na escola pública brasileira e pela sua falta de socialização na colaboração entre pares.

  5. Language Learning Styles Used By Students Of Basic English Course (Bec) Pare

    OpenAIRE

    HIDAYAH, ULFA NURUL

    2013-01-01

    Learning styles are the important factors to help students to learn a second or foreign language. A learning habit of every individual is needed to support the student's learning to be more effective, for example by taking an English course. Learning styles can be classified into: visual, auditory, kinesthetic, tactile, group, and individual. This study is conducted to examine the language learning styles applied by the students of Basic English Course (BEC) in Pare, Kediri. This study applie...

  6. How many food additives are rodent carcinogens?

    Science.gov (United States)

    Johnson, F M

    2002-01-01

    . Human experience with known carcinogens such as tobacco, asbestos, and benzidine convinces us that environmental carcinogens constitute a real threat to human health, although predicting human carcinogens from rodent tests involves a number of uncertainties. These uncertainties do not mean that we should simply ignore the presence of carcinogens. Rather, in the interests of public safety, a serious effort should be made to resolve the questions surrounding the presence of chemicals identified as rodent carcinogens in our food. Environ. Mol. Mutagen. 39:69-80, 2002 Published 2002 Wiley-Liss, Inc.

  7. Tutoría entre pares como una estrategia pedagógica universitaria Tutoria entre pares como estrategia pedagógica universitária Peer tutoring as an educational strategy in college

    Directory of Open Access Journals (Sweden)

    Claudia Esperanza Cardozo-Ortiz

    2011-08-01

    Full Text Available Se presenta la experiencia de "tutoría entre pares", desarrollada en una universidad de Bucaramanga, Colombia, con el propósito de crear condiciones y escenarios deformación universitaria que permitan autorregular los aprendizajes e incorporar nuevas estrategias en la relación pedagógica estudiante-profesor. El proceso metodológico etnográfico permitió leer e interpretar la realidad desde las categorías y subcategorías que emergieron en el análisis. Los resultados se organizaron en cuatro ejes, así: fusión de valores y academia, donde se comparte, se construye y se crean vínculos integradores; tutores que ejercen de aprendices y mediadores; actores educativos facilitadores de la labor tutorial, y necesidad de mayor compromiso de la comunidad universitaria.O artigo apresenta a experiência de "tutoria entre pares", desenvolvida em uma universidade de Bucaramanga (Colômbia a fim de criar condições e sitios de treinamento que permitem auto-regular as aprendizagens e incorporar novas estrategias de ensino na relação professor-aluno. A abordagem metodológica etnográfica permitiu ler e interpretar a realidade a partir das categorias e subcategorias que surgiram na análise. Os resultados foram agrupados em quatro áreas: fusão de valores e academia, onde são partilhados, construídos e criados vínculos integradores; tutores que são também aprendizes e mediadores; atores educativos facilitadores do trabalho de tutoria; e necessidade de obter maior empenho da comunidade universitária.This article describes a peer tutoring experience developed at a university in Bucaramanga, Colombia to create the conditions and scenarios required in higher education to self-regulate academic learning and incorporate new strategies into the student-teacher relationship. The ethnographic methodological process made it possible to understand and interpret existing circumstances based on the categories and sub-categories that emerged from the

  8. Uus Multiphonic Rodent

    Index Scriptorium Estoniae

    2009-01-01

    Tartus tegutsenud eksperimentaal-rock-duo Opium Flirt Eestisse jäänud liige Erki Hõbe (paarimees Ervin Trofimov tegutseb Ungaris) annab välja oma teise sooloalbumi nime all Multiphonic Rodent, heliplaadi "Astral Dance" esitluskontsert toimub 5. veebruaril Tallinnas baaris Juuksur

  9. Kadar Lipid Darah Mencit Betina Middle-Aged Galur Swiss Webster setelah Pemberian Jus Buah Pare (Momordica charantia L.

    Directory of Open Access Journals (Sweden)

    Rita Shintawati

    2011-06-01

    Full Text Available Ovarian aging has been noted in some vertebrate animals and human being, indicated by low estrogen level. This is related to enhancement of lipid (obesity and some metabolic diseases such as hyperlipidemia, cardiovascular disease, etc. Pare juice (Momordica charantia L., contains of abundant advantageous bioactivities, such as hypoglycemic effect, antioxidant, hypocholesterolemic, and hypotrigliseridemic. This research purposed was to determine blood lipid levels of mice at the age of middle-aged after being given pare juice. The experimental animal used 25 females mice of 10 months old (middle-aged on March–April 2010 at Physiology Laboratory Universitas Pendidikan Indonesia and Veteriner Medicine IPB, divided into five different treatment groups (controle positive, controle negative, 0.5 mL/40 g bw, 1.0 mL/40 g bw, and 1.5 mL/40 g bw which were fed with pare juice for 10 days. Completely randomized design was used in this research. Results showed that pare juice reduced lower body weight of mice (p<0.05 at all doses. Pare juice did not reduce total cholesterol levels, but increased HDL (p<0.05 at all doses. Other parameters to pare juice reduced triglyceride levels at doses of 1.5 mL/40 g BW (p<0.05 and LDL levels at dose 0.5 mL/40 g BW (136.49 mg/dL. In conclusions, pare juice can stabilize triglyseride and LDL cholesterol level at dose 0.5 mL/40 g BW and increases HDL cholesterol, but has no influence to total cholesterol.

  10. Maltrato entre pares o "bullying": Una visión actual

    OpenAIRE

    TRAUTMANN M, ALBERTO

    2008-01-01

    Se presenta una actualización sobre el acoso o maltrato escolar entre pares o "bullying". Se explica su significado, el rol y características de sus actores y sus consecuencias. Se menciona su epidemiología y los factores condicionantes que influyen en su presencia. Se revisan las intervenciones realizadas en los colegios y sus resultados, y se analiza el rol de los prestadores de salud. Se proponen indicaciones de consejería a la familia, con algunos datos útiles para usarlos en la consulta ...

  11. Harvesting behaviour of three central European rodents: Identifying the rodent pest in cereals

    Czech Academy of Sciences Publication Activity Database

    Heroldová, Marta; Tkadlec, Emil

    2011-01-01

    Roč. 30, č. 1 (2011), s. 82-84 ISSN 0261-2194 R&D Projects: GA MZe QH72075 Institutional research plan: CEZ:AV0Z60930519 Keywords : Apodemus sylvaticus * Apodemus uralensis * feeding behaviour * lab experiments * Microtus arvalis * rodent pest control Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 1.402, year: 2011

  12. Entretenimiento, espiritualidad, familia y la influencia de pares universitarios en el consumo de drogas

    Directory of Open Access Journals (Sweden)

    Aydee Rivera de Parada

    2015-01-01

    Full Text Available El objetivo del estudio fue examinar la relación de los factores socio-culturales de familia, entretenimiento y espiritualidad y la influencia de pares y el consumo de drogas entre los estudiantes universitarios. Estudio es multicéntrico, con un diseño transversal, participaron 250 estudiantes de una universidad en San Salvador, El Salvador. Se realizaron análisis porcentuales, pruebas de asociación y correlación. Se encontró que los factores socioculturales de familia y espiritualidad podrían estar protegiendo ya que la mayoría 80% valoran positivamente estos dos valores. La mayoría de estudiantes consumen muy poco drogas ilícitas, marihuana 2%, cocaína 1% y anfetaminas 1.2%; pero consume más las drogas lícitas alcohol 42%, tabaco 21%.

  13. Pressão social do grupo de pares na iniciação sexual de adolescentes Presión social del grupo de pares en la iniciación sexual de adolescentes Peer social pressure on the sexual debut of adolescents

    Directory of Open Access Journals (Sweden)

    Ana Luiza Vilela Borges

    2007-12-01

    Full Text Available Dado que a literatura enfatiza a estreita relação entre o início da vida sexual e a pressão exercida pelos pares, o objetivo deste trabalho foi identificar a presença da pressão social na iniciação sexual de adolescentes, com base nos relacionamentos com o grupo de iguais. Participaram 363 pessoas, com idade entre 15 e 19 anos, compreendendo uma amostra representativa dos adolescentes cadastrados em uma unidade do Programa de Saúde da Família da cidade de São Paulo. Foi utilizado um questionário estruturado e auto-aplicado. Os resultados mostraram associação entre a iniciação sexual e idade, já ter ficado com alguém sem vontade, ter a maior parte dos amigos com experiência sexual e estar namorando, o que revelou indícios de que os pares parecem exercer certa influência na opção pela iniciação sexual.Considerando que la literatura enfatiza la estrecha relación entre el inicio de la vida sexual y la presión ejercida por los pares, fue realizada una investigación para identificar la presencia de la presión social para la iniciación sexual de adolescentes, a partir de relacionamientos con su grupo de pares. Participaran 363 individuos, con edad entre 15 y 19 años, una muestra fue representativa de los adolescentes registrados en una unidad del Programa de Salud de la Familia de la ciudad de São Paulo. Fue utilizado cuestionario estructurado y auto-aplicado. Los resultados mostraron asociación entre la iniciación sexual y la edad, ya haber estado con alguien sin voluntad, tener amigos, en su mayoría con experiencia sexual y estar enamorando, lo que revela indicios de que los pares parecen ejercer cierta influencia para optar por la iniciación sexual.Considering that scientific articles have emphasized the link between the onset of sexual life and peer pressure, the aim of this study was to identify peer pressure in the adolescents' sexual initiation from the point of view of their relationship with the group of

  14. Configuração familiar, género e coping em adolescentes: papel dos pares

    Directory of Open Access Journals (Sweden)

    Mónica Costa

    2012-12-01

    Full Text Available Relações interpessoais estabelecidas no contexto de institucionalização, nomeadamente com os pares, são fontes relevantes de suporte emocional e facilitador do processo adaptativo na fase de transição para a adultícia. O objectivo do presente estudo prende-se com a análise da qualidade da ligação de adolescentes aos pares e do seu efeito preditor nas estratégias de coping dos jovens. Pretende-se ainda testar o papel moderador da configuração familiar e do género na associação entre a ligação aos pares e as estratégias de coping. A amostra é composta por 311 adolescentes, 145 institucionalizados e 166 de famílias tradicionais, entre os 14 e os 18 anos, de ambos os géneros. A recolha de dados foi realizada através da Rosenberg Self-esteem Scale (Rosenberg, 1965, Inventory of Peer and Parental Attachment (Armsden & Greenberg, 1987 e o COPE Inventory (Carver, Weintraub & Scheider, 1989. Os resultados sugerem que a qualidade da ligação aos pares se mostra relevante na predição das estratégias de coping adaptativas (coping activo e uso de suporte social emocional.

  15. EXTRACCIÓN Y CUANTIFICACIÓN DE LOS POLÍSACARIDOS DE LA PARED CELULAR DE LAS LEVADURAS

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    Elba M. Alcázar V

    2016-01-01

    Full Text Available Los polisacáridos de la pared celular de las levaduras, se dividen en: 1,3 B - gluc anos, 1,6 B - glucanos, manoproteínas y quitina. Estos componentes representan una fuente potencial de aplicaciones en la industria alimentaria y farmacéutica. Por lo tanto, p ara su extracción existen d iferentes protocolos, en donde para lograr la separación de los componentes de la pared se basan en su solubilidad en soluciones alcalinas y/o e n ácidos inorgánicos, que posteriormente son hidrolizados y usualmente cuantificado por técnicas espectrofotométricas con reactivos de fenol - ácido sulfúrico y/o con el reactivo de antrona . Algunas metodologías sólo extraen los componentes celulares en una fracción total, limitando su cuantificación y análisis para el desarrollo de nuevas aplicaciones en las industrias alimentaría y farmacéutica, mientras que otros método s dividen a la pared celular en sus tres componentes. No obstante, para su cuantificación y análisis utilizan metodologías extensas y complicadas . El objetivo del presente traba jo fue proponer un a metodología de extracción de la pared celular de dos cepas de levadura ( Saccharomyces cerevisiae y Kluyveromyces marxianus a través de una extracción alcalina , dividiendo en tres fracciones los componentes de la pared celular para su posterior cuantifica ción a partir de cromatografía de líquidos. Se encontró que las cepas de levadura empleadas presentan diferencias estadísticas significativas en la concentración de 1,3 B - glucanos, y que los rendimientos obtenidos en la extracción de la pared celular de am bas cepas de levadura son similares a los reportados en estudios previos. Por lo tanto, podemos concluir que la extracción de la pared celular empleando esta metodología es confiable.

  16. ANALISIS JULAT PASANG SURUT (TIDAL RANGE DAN PENGARUHNYA TERHADAP SEBARAN TOTAL SEDIMEN TERSUSPENSI (TSS DI PERAIRAN TELUK PARE

    Directory of Open Access Journals (Sweden)

    Ulung Jantama Wisha

    2016-03-01

    Full Text Available ANALYSIS OF TIDAL RANGE AND ITS EFFECT ON DISTRIBUTION OF TOTAL SUSPENDED SOLID (TSS IN THE PARE BAY WATERSPare Bay conditions is closely related to the mechanism of circulation in Makasar Strait. One of the problems that occur in Pare Bay waters is increased turbidity and low dynamics of transport inside the bay, which caused silting in some parts of the bay. The aim of this study was to determine tidal range characteristics and the influence of suspended sediment distribution as analysis of the sedimentation process and siltation at Pare bay. Descriptive quantitative method was used and the survey location was based on purposive sampling method. Tidal type in Pare Bay water was mix mainly semidiurnal tides with Formzahl Value was 0.895. The value of the water level below the lowest tide (Z0 was 1036.44 cm. Mean sea level (MSL value was 1107.97 cm. The vertical datum of MHHWS and MLLWS were 1143.47 cm and 1072.47 cm. Tidal range cycle in spring condition was 102-129,56 cm bigger than cycle in neap condition ranged from 55.53-82.47 cm. TSS concentrations ranged from 0-7.0 mg/L in the surface and ranged from 0- 10.0 mg/L in 5 meters depth. At high tide down, sediment was settling and at the time of high tide, sediment mixed back.Keywords: Pare Bay, suspended solid, tidal range, tide.ABSTRAKKondisi perairan di Teluk Pare sangat berkaitan dengan mekanisme sirkulasi di Selat Makasar, Permasalahan yang terjadi di Teluk Pare salah satunya adalah tingginya tingkat kekeruhan dan rendahnya dinamika transport didalam teluk yang menyebabkan pendangkalan di beberapa bagian teluk. Tujuan dari penelitian ini adalah mengetahui karakteristik julat pasang surut dan pengaruhnya terhadap sebaran sedimen tersuspensi sebagai analisis proses sedimentasi dan pendangkalan di perairan Teluk Pare. Metode penelitian yang digunakan adalah deskriptif kuantitatif, metode penentuan lokasi titik pengambilan sampel air yaitu metode purposive sampling. Tipe pasang surut Teluk

  17. Nuestra conducta en la asociación de hernia de pared y abdominoplastia estética

    Directory of Open Access Journals (Sweden)

    José H. Soria

    Full Text Available Antecedentes y Objetivos. La liposucción es una técnica frecuente en el contexto de una abdominoplastia estética, pero puede ser causa de una seria complicación como es la perforación de una víscera intrabdominal, cuando la presencia de una hernia de pared no ha sido diagnosticada oportunamente. La ecografía es la primera opción como estudio preoperatorio y la tomografía axial computerizada (TAC es secundaria en pacientes obesos. Describimos la hernioplastia sin uso de material aloplástico y la reconstrucción del ombligo cuando se debe eliminar la cicatriz umbilical, todo ello dentro del marco de una abdominoplastia estética. Pacientes y Método. Revisamos entre enero de 2005 y diciembre de 2012, 104 pacientes sometidas a abdominoplastia estética en las que se solicitó en el preoperatorio ecografía y/o TAC de pared abdominal. Resultados. El 30% de las pacientes pertenecían al Tipo III y el 70% al Tipo IV según clasificación de Matarasso. El 27% presentaban hernia de pared abdominal: hernia umbilical directa 26%; hernia umbilical indirecta 33%; hernia epigástrica 37% y hernia infraumbilical 4%. De las ecografías solicitadas obtuvimos 25% diagnósticos positivos; 3% falsos negativos y 72% verdaderos negativos. De las TAC obtuvimos 25% positivos y 75% negativos. Conclusiones. La ecografía de la pared abdominal es útil pero insuficiente para el diagnóstico preoperatorio de hernia de pared abdominal cuando se va a realizar una abdominoplastia estética, debido a la ocurrencia de falsos negativos. La TAC es el complemento adecuado para los casos de difícil diagnóstico.

  18. The rodent ultrasound production mechanism.

    Science.gov (United States)

    Roberts, L H

    1975-03-01

    Rodents produce two types of sounds, audible and ultrasonic, that differ markedly in physical structure. Studies of sound production in light gases show that whereas the audible cries appear to be produced, as in the case of most other mammals, by vibrating structures in the larynx, the ultrasonic cries are produced by a different mechanism, probably a whistle. 'Bird-call' whistles are shown to have all the properties of rodent ultrasonic cries and to mimic them in almost every detail. Thus it is concluded that rodents have two distinct sound production mechanisms, one for audible cries and one for ultrasonic cries.

  19. Virtual reality systems for rodents.

    Science.gov (United States)

    Thurley, Kay; Ayaz, Aslı

    2017-02-01

    Over the last decade virtual reality (VR) setups for rodents have been developed and utilized to investigate the neural foundations of behavior. Such VR systems became very popular since they allow the use of state-of-the-art techniques to measure neural activity in behaving rodents that cannot be easily used with classical behavior setups. Here, we provide an overview of rodent VR technologies and review recent results from related research. We discuss commonalities and differences as well as merits and issues of different approaches. A special focus is given to experimental (behavioral) paradigms in use. Finally we comment on possible use cases that may further exploit the potential of VR in rodent research and hence inspire future studies.

  20. A linguagem idiomática organizada em pares dicotômicos

    Directory of Open Access Journals (Sweden)

    Huélinton Cassiano Riva

    2005-07-01

    Full Text Available

    Neste trabalho são apresentadas as particularidades concernentes a uma proposta de dicionário de expressões idiomáticas do português do Brasil em uma perspectiva onomasiológica. Trata-se da organização dos idiomatismos em dez pares de conceitos dicotômicos, analisados como os mais produtivos do português, do ponto de vista fraseológico: 1. amor/ódio; 2. beleza/feiúra; 3. confiança/traição; 4. conhecimento/ignorância; 5. coragem/medo; 6. felicidade/infortúnio; 7. rapidez/lentidão; 8. riqueza/pobreza; 9. serenidade/agressividade; 10. sucesso/fracasso. Também é evidenciada a importância da utilização de corpora eletrônicos para a demonstração do idiomatismo em um contexto real e considerada a multifuncionalidade do percurso onomasiológico, que revela informações tanto sobre a organização social e histórica ou sobre a cultura de um povo, como sobre a natureza psicológica das escolhas dos falantes.

  1. Cuerpos textiles retenidos en la pared torácica. Una situación infrecuente

    Directory of Open Access Journals (Sweden)

    Carlos M. Abril

    2017-11-01

    Full Text Available Resumen: Los cuerpos extraños retenidos después de intervenciones quirúrgicas son una complicación potencialmente grave. Se presenta el caso de una paciente de 63 años con imagen de densidad aumentada en radiología simple de tórax tras una intervención en región axilar derecha 3 años antes. En la reintervención se extrajo una masa fibrótica que resultó ser una compresa quirúrgica con material radioopaco. Se discuten los problemas relacionados con cuerpos retenidos. Abstract: Retained foreign bodies after surgery are a potentially serious complication. The case is presented of a 63year-old female with an image with increased density in the plain chest X-ray after a previous operation in the right axillary region three years earlier. On re-operation a fibrotic mass was removed. This was a surgical sponge with a radio-opaque marker. Problems related to retained foreign bodies are discussed. Palabras clave: Cuerpo extraño, Textil, Pared torácica, Keywords: Foreign body, Textile, Chest wall

  2. Sintomatología en adolescentes victimizados sexualmente: El rol del apoyo de la familia y del grupo de pares

    Directory of Open Access Journals (Sweden)

    Cristobal Guerra

    2016-11-01

    Full Text Available Existe suficiente evidencia de que el apoyo que entrega la familia, especialmente los padres, previene la aparición de sintomatología en adolescentes que han sufrido abuso sexual. No obstante, el estudio del rol que juega el apoyo entregado por el grupo de pares no ha sido suficientemente investigado y las pocas investigaciones en la materia han entregado resultados contradictorios. De este modo, el objetivo del presente estudio es evaluar la relación tanto del apoyo de la familia, como del de los pares con la sintomatología depresiva, ansiosa y de estrés postraumático en víctimas de abuso sexual. Participaron 93 adolescentes de género femenino (edades entre 12 y 17 años. Las participantes respondieron escalas para evaluar la sintomatología y para evaluar su percepción del apoyo social recibido. Los resultados de un análisis de regresión múltiple muestran que la percepción de apoyo por parte de la familia se asocia inversamente a los tres tipos de síntomas. En cambio, la percepción de apoyo de los pares únicamente se asocia inversamente a la sintomatología depresiva. Estos resultados dan cuenta de que la familia sigue siendo el principal agente protector, aún en la etapa de la adolescencia. Los pares, en cambio, poseerían menos recursos de protección y su rol estaría más centrado en la distracción.

  3. Entre el perdón y el paredón: Preguntas y dilemas de la justicia ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    In this way, Entre el perdón y el paredón helps not only to identify the challenges that Colombian society will have to face to overcome its current armed conflict, but also ... Angelika Rettberg, PhD, is a professor in the Department of Political Science in the Faculty of Social Sciences at the Universidad de los Andes, and is the ...

  4. Normas percebidas por estudantes universitários sobre o uso de álcool pelos pares Normas percibidas por los estudiantes universitarios sobre el uso de alcohol entre sus pares Perceived norms of peer alcohol use among university students

    Directory of Open Access Journals (Sweden)

    Elias Barbosa de Oliveira

    2009-01-01

    Full Text Available O álcool é a droga lícita de maior prevalência entre estudantes universitários e consumida de forma recreacional. Os objetivos deste estudo foram identificar as normas percebidas sobre o uso de álcool entre estudantes universitários, contrastar a percepção dos estudantes em relação ao uso de álcool por seus pares com a atual prevalência do uso de álcool e comparar o próprio uso de álcool com a percepção do uso de álcool pelos pares. Utilizou-se a técnica (survey com 275 estudantes de uma universidade pública do Rio de Janeiro (Brasil, em 2008. A percepção dos estudantes sobre o uso de álcool pelos pares uma vez na vida e nos últimos doze meses foi acurada, porém, em relação aos últimos trinta dias houve percepção errônea (hiperestimativa. Os estudantes consomem bebidas alcoólicas de forma recreacional, principalmente em festas e bares, em companhia de amigos e pares. O consumo se mostra acima dos padrões estabelecidos.El alcohol es la droga lícita de mayor consumo entre estudiantes universitarios, siendo su consumo considerado como de diversión. Los objetivos de este estudio fueron identificar las normas percibidas sobre el uso del alcohol entre estudiantes universitarios. Se deseaba comparar la percepción que los estudiantes tenían en relación al uso de alcohol entre sus pares con el uso real que los propios estudiantes hacían del alcohol. Se utilizó la técnica de la encuesta en 275 estudiantes, en una universidad pública de Río de Janeiro, en Brasil, en 2008. Se encontró que la percepción de los estudiantes sobre el uso del alcohol entre sus pares, en alguna vez en la vida y en los últimos doce meses, fue exacta, pero en relación a los últimos treinta días tuvieron una percepción errónea, esta fue sobreestimada. También, los estudiantes consumen bebidas alcohólicas para divertirse, principalmente en fiestas y bares en compañía de amigos y pares. Finalmente se encontró que el consumo es

  5. Tumores primarios de la pared torácica Primary tumors of the thorax wall

    Directory of Open Access Journals (Sweden)

    Bárbaro Agustín Armas Pérez

    2011-09-01

    Full Text Available Introducción: se revisan aspectos teóricos en los tumores primarios de la pared torácica, sobre todo en la clasificación y en aspectos clínicos, diagnósticos y terapéuticos, con el propósito de conocer los resultados del tratamiento en el centro. Métodos: se realizó un estudio retrospectivo descriptivo para analizar los resultados del tratamiento quirúrgico en 22 pacientes (muestra con tumores primarios de la pared torácica, en un período de 15 años (enero de 1993 a diciembre de 2008, en los servicios de cirugía general y ortopedia del Hospital "Amalia Simoni" de Camagüey. Resultados: hubo ligero predominio del sexo femenino y del grupo de edad entre 17 a 44 años (media 39,4, la comorbilidad que predominó fue la hipertensión arterial, el hemitórax derecho fue el más afectado, y las costillas de la 1 a la 4 las más lesionadas, y predominaron las afecciones benignas, entre ellas, el osteocondroma. El tratamiento más utilizado fue la resección quirúrgica, y la complicación posoperatoria que predominó fue la bronconeumonía. El índice de recidiva tumoral fue alto, no siempre por cáncer. Hubo 4 fallecidos por enfermedad maligna avanzada, y no se presentaron muertes perioperatorias. Conclusiones: fueron comparados los resultados con los de otros reportes y se hallaron puntos de coincidencia en diversos aspectos, pero también discrepantes, se trata de unificar criterios para mejorar el diagnóstico y los resultados del tratamiento en estos enfermos. La mayoría de los pacientes no presentaron complicaciones, y la recidiva tumoral estuvo por encima de lo esperado. La resección tumoral siempre debe ser amplia. El resultado global fue satisfactorio.Introduction: the theoretical features in the primary tumors of the thorax wall, especially in the classification and clinical, diagnostic y therapeutical features were reviewed to know the results of treatment in our institution. Methods: a descriptive and retrospective study was

  6. Forecasting rodent outbreaks in Africa

    DEFF Research Database (Denmark)

    Leirs, Herwig; Verhagen, Ron; Verheyen, Walter

    1996-01-01

    1. Rainfall data were collated for years preceding historical outbreaks of Mastomys rats in East Africa in order to test the hypothesis that such outbreaks occur after long dry periods. 2. Rodent outbreaks were generally not preceded by long dry periods. 3. Population dynamics of Mastomys...... natalensis rats in Tanzania are significantly affected by the distribution of rainfall during the rainy season. 4. All previous rodent outbreaks in Tanzania were preceded by abundant rainfall early in the rainy season, i.e, towards the end of the year. 5. A flow chart is constructed to assess the likelihood...

  7. Identifikasi Golongan Senyawa Kimia Estrak Etanol Buah Pare (Momordica charantia dan Pengaruhnya Terhadap Penurunan Kadar Glukosa Darah Tikus Putih Jantan (Rattus novergicus yang Diinduksi Aloksan

    Directory of Open Access Journals (Sweden)

    I Ketut Angga Yuda

    2013-08-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui golongan senyawa kimia ekstrak etanol buah pare (M. charantia sebagai penurun kadar glukosa darah tikus putih jantan (R. novergicus yang diinduksi aloksan. Sampel penelitian ini adalah 25 ekor tikus putih jantan (R. novergicus berumur 3 bulan dengan berat rata-rata 150-300 g. Rancangan yang digunakan berupa Rancangan Acak Lengkap (RAL dengan lima perlakuan sebagai berikut, perlakuan I sebagai kontrol yaitu tikus normal tanpa perlakuan, Perlakuan II kontrol diabetes, perlakuan III tikus diabetes dan ekstrak buah pare 100 mg/kg bb, perlakuan IV tikus diabetes dan ekstrak buah pare 50 mg/kg bb, dan perlakuan V tikus diabetes dan glibenklamid 1 mg/kg bb. Hasil penelitan menunjukan buah pare mengandung zat flavonoid, polifenol, dan saponin. Pemberian ekstrak etanol buah pare (M. charantia dapat menurunkan kadar glukosa darah tikus putih (R. novergicus penderita diabetes dengan diinduksi aloksan secara signifikan P<0,05 yang sebanding dengan pemberian glibenklamid. Dengan demikian, ekstrak etanol buah pare dapat digunakan sebagai penurun kadar glukosa darah.

  8. Convergent and Divergent Adaptations of Subterranean Rodents

    DEFF Research Database (Denmark)

    Fang, Xiaodong

    Subterranean rodents comprise approximately 250 species that spend their entire lives in underground, unventilated tunnels, distributed along all continents except Australia and Antarctica. Subterranean rodents escape from predators and extreme climatic fluctuations in their underground habitats,...

  9. Guide to Commensal Rodent Control

    Science.gov (United States)

    1991-12-01

    in many detergents also fluoresce. For positive identification, place the suspect material on Urease Siom lhymol Blue test paper, moisten with water...are applied in a thin layer in protected rat and mouse r’unways, baitboxes, or tubes along walls. The powder is picked up by the rodents on their feet

  10. The Ethics of Rodent Control

    NARCIS (Netherlands)

    Meerburg, B.G.; Brom, F.W.A.; Kijlstra, A.

    2008-01-01

    Because western societies generally see animals as objects of moral concern, demands have been made on the way they are treated, e.g. during animal experimentation. In the case of rodent pests, however, inhumane control methods are often applied. This inconsistency in the human-animal relationship

  11. A biometric approach to laboratory rodent identification.

    Science.gov (United States)

    Cameron, Jens; Jacobson, Christina; Nilsson, Kenneth; Rögnvaldsson, Thorsteinn

    2007-03-01

    Individual identification of laboratory rodents typically involves invasive methods, such as tattoos, ear clips, and implanted transponders. Beyond the ethical dilemmas they may present, these methods may cause pain or distress that confounds research results. The authors describe a prototype device for biometric identification of laboratory rodents that would allow researchers to identify rodents without the complications of other methods. The device, which uses the rodent's ear blood vessel pattern as the identifier, is fast, automatic, noninvasive, and painless.

  12. 21 CFR 1250.96 - Rodent control.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rodent control. 1250.96 Section 1250.96 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.96 Rodent control. Vessels shall be... of rodent control. ...

  13. The water economy of South American desert rodents: from integrative to molecular physiological ecology.

    Science.gov (United States)

    Bozinovic, Francisco; Gallardo, Pedro

    2006-01-01

    Rodents from arid and semi-arid habitats live under conditions where the spatial and temporal availability of free water is limited, or scarce, thus forcing these rodents to deal with the problem of water conservation. The response of rodents to unproductive desert environments and water deficits has been intensively investigated in many deserts of the world. However, current understanding of the cellular, systemic and organismal physiology of water economy relies heavily on short-term, laboratory-oriented experiments, which usually focus on responses at isolated levels of biological organization. In addition, studies in small South American mammals are scarce. Indeed xeric habitats have existed in South America for a long time and it is intriguing why present day South American desert rodents do not show the wide array of adaptive traits to desert life observed for rodents on other continents. Several authors have pointed out that South American desert rodents lack physiological and energetic specialization for energy and water conservation, hypothesizing that their success is based more on behavioral and ecological strategies. We review phenotypic flexibility and physiological diversity in water flux rate, urine osmolality, and expression of water channels in South American desert-dwelling rodents. As far as we know, this is the first review of integrative studies at cellular, systemic and organismal levels. Our main conclusion is that South American desert rodents possess structural as well as physiological systems for water conservation, which are as remarkable as those found in "classical" rodents inhabiting other desert areas of the world.

  14. Stress, social behavior, and resilience: Insights from rodents

    Science.gov (United States)

    Beery, Annaliese K.; Kaufer, Daniela

    2014-01-01

    The neurobiology of stress and the neurobiology of social behavior are deeply intertwined. The social environment interacts with stress on almost every front: social interactions can be potent stressors; they can buffer the response to an external stressor; and social behavior often changes in response to stressful life experience. This review explores mechanistic and behavioral links between stress, anxiety, resilience, and social behavior in rodents, with particular attention to different social contexts. We consider variation between several different rodent species and make connections to research on humans and non-human primates. PMID:25562050

  15. Prenatal stressors in rodents: Effects on behavior

    Directory of Open Access Journals (Sweden)

    Marta Weinstock

    2017-02-01

    Full Text Available The current review focuses on studies in rodents published since 2008 and explores possible reasons for any differences they report in the effects of gestational stress on various types of behavior in the offspring. An abundance of experimental data shows that different maternal stressors in rodents can replicate some of the abnormalities in offspring behavior observed in humans. These include, anxiety, in juvenile and adult rats and mice, assessed in the elevated plus maze and open field tests and depression, detected in the forced swim and sucrose-preference tests. Deficits were reported in social interaction that is suggestive of pathology associated with schizophrenia, and in spatial learning and memory in adult rats in the Morris water maze test, but in most studies only males were tested. There were too few studies on the novel object recognition test at different inter-trial intervals to enable a conclusion about the effect of prenatal stress and whether any deficits are more prevalent in males. Among hippocampal glutamate receptors, NR2B was the only subtype consistently reduced in association with learning deficits. However, like in humans with schizophrenia and depression, prenatal stress lowered hippocampal levels of BDNF, which were closely correlated with decreases in hippocampal long-term potentiation. In mice, down-regulation of BDNF appeared to occur through the action of gene-methylating enzymes that are already increased above controls in prenatally-stressed neonates. In conclusion, the data obtained so far from experiments in rodents lend support to a physiological basis for the neurodevelopmental hypothesis of schizophrenia and depression.

  16. Radionuclides in rodents

    International Nuclear Information System (INIS)

    Taylor, G.N.

    1985-01-01

    Studies are being conducted in mice comparing the toxicity of radium-226, plutonium-239, americium-241, californium-249 and californium-252 in C57B1/Do (albino) mice and the toxicity of americium-241, plutonium-239 and radium-226 in deer mice (Peromyscus maniculatus) and grasshopper mice (Onychomys leucogaster). These experiments will ultimately enable comparison of the toxicity of the above actinide toxicity in man to be made using radium toxicity as the baseline

  17. Allometric disparity in rodent evolution

    OpenAIRE

    Wilson LAB

    2013-01-01

    In this study, allometric trajectories for 51 rodent species, comprising equal representatives from each of the major clades (Ctenohystrica, Muroidea, Sciuridae), are compared in a multivariate morphospace (=allometric space) to quantify magnitudes of disparity in cranial growth. Variability in allometric trajectory patterns was compared to measures of adult disparity in each clade, and dietary habit among the examined species, which together encapsulated an ecomorphological breadth. Results ...

  18. Violência entre pares: um estudo de caso numa escola pública de Esteio/RS

    Directory of Open Access Journals (Sweden)

    Carla Elizabeth da Silva

    Full Text Available Este estudo investiga a "violência entre pares" numa escola de Esteio/RS. Participaram 161 alunos, sendo 102 da sétima e 59 da oitava série, 67 meninas e 94 meninos, com idades entre 12 e 20 anos (M ± DP = 14,09 ± 1,19. Foi utilizado o questionário "Violência entre Pares". Os resultados mostram que 56,9% dos alunos foram vítimas, 82,0%, observadores e 38,5%, agressores. Apenas 8,7% foram agredidos mais de três vezes. A agressão mais frequente foi a verbal (47,2%, seguida da física (21,1% e de outras formas de agressão (13,7%. Discute-se o perfil dos agressores, que são predominantemente também vítimas, e 70,3% destas têm irmãos mais velhos. Há queda dos índices de vitimização nos meninos conforme aumenta a idade. A maioria dos alunos avaliou o ambiente escolar e a relação com os colegas como positiva, sem associação entre vitimização e piora dessas avaliações. A presença do bullying não foi significativa.

  19. Flexibilidad Cognitiva para Resolver Problemas entre Pares ¿Difiere esta Capacidad en Escolares de Contextos Urbanos y Urbanomarginales?

    Directory of Open Access Journals (Sweden)

    Silvina Laura Maddio

    2010-01-01

    Full Text Available La flexibilidad cognitiva para solucionar problemas interpersonales implica: generar respuestas con control inhibitorio funcional y considerar las consecuencias positivas en todas las personas. Se aplicó este concepto a los problemas entre pares, éstos conllevan emociones negativas, agresiones y rechazo (Bukowski, Hoza, & Boiven, 1993; Feldman, Rubenstein, & Rubin, 1988; Moreno, 2007. Objetivos: definir y comparar la flexibilidad cognitiva para solucionar problemas entre pares en niños de escuelas urbanas y urbanomarginales y describir sus características socioculturales. Estudio: empírico, transversal- descriptivo. Muestra: 120 escolares de 8 años de escuelas estatales de Argentina, n=60 (urbana y n=60 (urbanomarginal. Análisis de datos: Prueba t de diferencia entre medias (muestras independientes. Los resultados mostraron diferencias significativas en respuestas de flexibilidad cognitiva media e irrelevantes. Se aporta al diseño de programas para promover comportamientos socialmente competentes, bienestar y paz en niños/as.

  20. Semi-Autonomous Rodent Habitat for Deep Space Exploration

    Science.gov (United States)

    Alwood, J. S.; Shirazi-Fard, Y.; Pletcher, D.; Globus, R.

    2018-01-01

    NASA has flown animals to space as part of trailblazing missions and to understand the biological responses to spaceflight. Mice traveled in the Lunar Module with the Apollo 17 astronauts and now mice are frequent research subjects in LEO on the ISS. The ISS rodent missions have focused on unravelling biological mechanisms, better understanding risks to astronaut health, and testing candidate countermeasures. A critical barrier for longer-duration animal missions is the need for humans-in-the-loop to perform animal husbandry and perform routine tasks during a mission. Using autonomous or telerobotic systems to alleviate some of these tasks would enable longer-duration missions to be performed at the Deep Space Gateway. Rodent missions performed using the Gateway as a platform could address a number of critical risks identified by the Human Research Program (HRP), as well as Space Biology Program questions identified by NRC Decadal Survey on Biological and Physical Sciences in Space, (2011). HRP risk areas of potentially greatest relevance that the Gateway rodent missions can address include those related to visual impairment (VIIP) and radiation risks to central nervous system, cardiovascular disease, as well as countermeasure testing. Space Biology focus areas addressed by the Gateway rodent missions include mechanisms and combinatorial effects of microgravity and radiation. The objectives of the work proposed here are to 1) develop capability for semi-autonomous rodent research in cis-lunar orbit, 2) conduct key experiments for testing countermeasures against low gravity and space radiation. The hardware and operations system developed will enable experiments at least one month in duration, which potentially could be extended to one year in duration. To gain novel insights into the health risks to crew of deep space travel (i.e., exposure to space radiation), results obtained from Gateway flight rodents can be compared to ground control groups and separate groups

  1. Genesis and evolution of the sonnet (chahar-pare composing in Iran

    Directory of Open Access Journals (Sweden)

    Bbagher Sadrinia

    2015-04-01

    Full Text Available Abstract Persian "Sonnets" (chahar-pare or "continuous quatrains" are already mentioned briefly here and there but the emergence, evolution and the influence of the modern ottoman poetry on the inclination of Persian poets to this new poetic form have not been thoroughly discussed yet. The author of this paper, while studying the origin of this form of poetry by referring to its currency in French literature, seeks to answer the following questions: 1 – Did the Iranian poets compose sonnets under the influence of European and especially French literature? 2 – How much did the ottoman modern poetry influence the inclination of Iranian poets to this form? 3 –When did sonnet composing begin exactly and who first composed his poem in this form?    It seems that there is no doubt about the idea that this form of sonnets or continuous quatrains as a new form in Persian poetic was borrowed from the European and especially French literature, but it is disputable whether the Iranians received this form and its special rhyme scheme directly from Europeans or they got accustomed with it through an intermediary language?    From the viewpoint of the author these continuous quatrains were first considered by modern Turkish poets of Tanzimat and constitutional Revolution period such as Akif Paşa (1316 AH, and later Ibrahim Şinasi (d. 1871 CE, Ziya Paşaa (d. 1881 CE, Namik Kemal (d. 1888 CE and the poets of the next generation such as Recaizade Ekrem Beik (d. 1914 CE and Abdülhak Hamit Tarhan (d. 1937 CE Tevfik Fikret (d. 1915 CE who were familiar with french poetry and literature (Habib, 1340: 95 then this form entered Iranian literature via Turkish language and literature. On the one hand the distant priority of the Turkish modernist poets in using this form and on the other hand the familiarity of the first Iranian sonnet-composer poets such as Ja’far Xamene’i, Lahuti and Taqi Raf’at with the modern ottoman poetry and literature confirms

  2. Genesis and evolution of the sonnet (chahar-pare composing in Iran

    Directory of Open Access Journals (Sweden)

    Bbagher Sadrinia

    2015-03-01

    Full Text Available Abstract Persian "Sonnets" (chahar-pare or "continuous quatrains" are already mentioned briefly here and there but the emergence, evolution and the influence of the modern ottoman poetry on the inclination of Persian poets to this new poetic form have not been thoroughly discussed yet. The author of this paper, while studying the origin of this form of poetry by referring to its currency in French literature, seeks to answer the following questions: 1 – Did the Iranian poets compose sonnets under the influence of European and especially French literature? 2 – How much did the ottoman modern poetry influence the inclination of Iranian poets to this form? 3 –When did sonnet composing begin exactly and who first composed his poem in this form?    It seems that there is no doubt about the idea that this form of sonnets or continuous quatrains as a new form in Persian poetic was borrowed from the European and especially French literature, but it is disputable whether the Iranians received this form and its special rhyme scheme directly from Europeans or they got accustomed with it through an intermediary language?    From the viewpoint of the author these continuous quatrains were first considered by modern Turkish poets of Tanzimat and constitutional Revolution period such as Akif Paşa (1316 AH, and later Ibrahim Şinasi (d. 1871 CE, Ziya Paşaa (d. 1881 CE, Namik Kemal (d. 1888 CE and the poets of the next generation such as Recaizade Ekrem Beik (d. 1914 CE and Abdülhak Hamit Tarhan (d. 1937 CE Tevfik Fikret (d. 1915 CE who were familiar with french poetry and literature (Habib, 1340: 95 then this form entered Iranian literature via Turkish language and literature. On the one hand the distant priority of the Turkish modernist poets in using this form and on the other hand the familiarity of the first Iranian sonnet-composer poets such as Ja’far Xamene’i, Lahuti and Taqi Raf’at with the modern

  3. Normas percibidas por estudiantes peruanos acerca de sus pares y el uso de drogas Normas percebidas por estudantes peruanos sobre uso de drogas entre seus pares Perceived norms among peruvian students for drug use among peers

    Directory of Open Access Journals (Sweden)

    Inés V. Bustamante

    2009-01-01

    Full Text Available El objetivo de este estudio fue estimar la diferencia entre las normas percibidas sobre el uso de drogas por sus pares y el uso real de drogas entre universitarios, entre 18 y 24 años, de las áreas de salud. Se trata de un estudio transversal, basado en un censo y en un cuestionario anónimo y autoaplicado. Participaron 306 estudiantes (82%. La proporción del consumo, en el último año, fue de 51,3% para el tabaco, 90,8% para el alcohol, 5,9% para la marihuana y 0,7% para la cocaína. Se observó una diferencia entre la norma percibida de consumo y la proporción de uso real informado para el tabaco (70% vs. 51.3%, marihuana (10% vs. 5.9% y cocaína (8.3% vs. 0.7%. Se concluye que los universitarios sobrestiman el consumo de tabaco, marihuana y cocaína de sus pares.O objetivo deste estudo foi avaliar a diferença entre as normas percebidas pelos estudantes universitários, com idade entre 18 e 24 anos, sobre o uso de drogas pelos seus pares e o uso de drogas relatado pelos próprios estudantes em cursos da área da saúde. Foi usado o método transversal, baseado em censo realizado através de questionário, preenchido pelos próprios estudantes, sem identificação. O número de participantes foi de 306 (82%. Como resultados obteve-se: a proporção de estudantes que utilizou drogas no último ano foi de 51,3% para o tabaco, 90,8% para o álcool, 5,9% para a maconha e 0,7% para a cocaína. Diferença entre as normas percebidas e o uso de drogas foi observada para o tabaco (70% vs 51,3%, maconha (10% vs 5.9% e cocaína (8,3% vs 0,7%. Conclui-se que os estudantes universitários apresentaram estimativa aumentada sobre o consumo de tabaco, maconha e cocaína entre seus pares.Objective: to evaluate the difference between perceived norms about drug use among peer and actual drug use as reported by the same university students. The students were between 18 and 24 years old and attended health courses. Method: cross-sectional study based on a

  4. Urban resident attitudes toward rodents, rodent control products, and environmental effects

    Science.gov (United States)

    Rodent control in urban areas can result in the inadvertent mortality of non-target species (e.g., bobcats). However, there is little detailed information about rodent control practices of urban residents. Our objective was to evaluate urban rodent control behaviors in two area...

  5. Dois pares de irmãos com artrite idiopática juvenil (AIJ: relato de casos

    Directory of Open Access Journals (Sweden)

    Teresa Cristina M.V. Robazzi

    2015-02-01

    Full Text Available Relato de casos de ocorrência de Artrite Idiopática Juvenil (AIJ em dois pares de irmãos acompanhados no serviço de reumatologia pediátrica da Universidade Federal da Bahia. O envolvimento genético na patogênese da AIJ está claro e o risco de recorrência entre irmãos corrobora esta contribuição. Um importante marco dessa descoberta envolve a confirmação da contribuição dos polimorfismos do complexo principal de histocompatibilidade (MHC na susceptibilidade ao desenvolvimento da AIJ. Apesar de muitos progressos, os inúmeros estudos existentes ainda não são capazes de explicar diversos mecanismos implícitos na patogênese da AIJ.

  6. Thermoregulation of the subterranean rodent genus Bathyergus ...

    African Journals Online (AJOL)

    The thermoregulation of the largest subterranean rodent, genus Bathyergus, comprising two species, B. suillus and B. janetta,occurring in mesic and semiarid habitats respectively, was investigated and compared with that of other subterranean rodents. Both species display low resting metabolic rates and low body ...

  7. Rodent Research on the International Space Station - A Look Forward

    Science.gov (United States)

    Kapusta, A. B.; Smithwick, M.; Wigley, C. L.

    2014-01-01

    Rodent Research on the International Space Station (ISS) is one of the highest priority science activities being supported by NASA and is planned for up to two flights per year. The first Rodent Research flight, Rodent Research-1 (RR-1) validates the hardware and basic science operations (dissections and tissue preservation). Subsequent flights will add new capabilities to support rodent research on the ISS. RR-1 will validate the following capabilities: animal husbandry for up to 30 days, video downlink to support animal health checks and scientific analysis, on-orbit dissections, sample preservation in RNA. Later and formalin, sample transfer from formalin to ethanol (hindlimbs), rapid cool-down and subsequent freezing at -80 of tissues and carcasses, sample return and recovery. RR-2, scheduled for SpX-6 (Winter 20142015) will add the following capabilities: animal husbandry for up to 60 days, RFID chip reader for individual animal identification, water refill and food replenishment, anesthesia and recovery, bone densitometry, blood collection (via cardiac puncture), blood separation via centrifugation, soft tissue fixation in formalin with transfer to ethanol, and delivery of injectable drugs that require frozen storage prior to use. Additional capabilities are also planned for future flights and these include but are not limited to male mice, live animal return, and the development of experiment unique equipment to support science requirements for principal investigators that are selected for flight. In addition to the hardware capabilities to support rodent research the Crew Office has implemented a training program in generic rodent skills for all USOS crew members during their pre-assignment training rotation. This class includes training in general animal handling, euthanasia, injections, and dissections. The dissection portion of this training focuses on the dissection of the spleen, liver, kidney with adrenals, brain, eyes, and hindlimbs. By achieving and

  8. Rodent Models for Metabolic Syndrome Research

    Directory of Open Access Journals (Sweden)

    Sunil K. Panchal

    2011-01-01

    Full Text Available Rodents are widely used to mimic human diseases to improve understanding of the causes and progression of disease symptoms and to test potential therapeutic interventions. Chronic diseases such as obesity, diabetes and hypertension, together known as the metabolic syndrome, are causing increasing morbidity and mortality. To control these diseases, research in rodent models that closely mimic the changes in humans is essential. This review will examine the adequacy of the many rodent models of metabolic syndrome to mimic the causes and progression of the disease in humans. The primary criterion will be whether a rodent model initiates all of the signs, especially obesity, diabetes, hypertension and dysfunction of the heart, blood vessels, liver and kidney, primarily by diet since these are the diet-induced signs in humans with metabolic syndrome. We conclude that the model that comes closest to fulfilling this criterion is the high carbohydrate, high fat-fed male rodent.

  9. Inbred or Outbred? Genetic Diversity in Laboratory Rodent Colonies

    Science.gov (United States)

    Brekke, Thomas D.; Steele, Katherine A.; Mulley, John F.

    2017-01-01

    Nonmodel rodents are widely used as subjects for both basic and applied biological research, but the genetic diversity of the study individuals is rarely quantified. University-housed colonies tend to be small and subject to founder effects and genetic drift; so they may be highly inbred or show substantial genetic divergence from other colonies, even those derived from the same source. Disregard for the levels of genetic diversity in an animal colony may result in a failure to replicate results if a different colony is used to repeat an experiment, as different colonies may have fixed alternative variants. Here we use high throughput sequencing to demonstrate genetic divergence in three isolated colonies of Mongolian gerbil (Meriones unguiculatus) even though they were all established recently from the same source. We also show that genetic diversity in allegedly “outbred” colonies of nonmodel rodents (gerbils, hamsters, house mice, deer mice, and rats) varies considerably from nearly no segregating diversity to very high levels of polymorphism. We conclude that genetic divergence in isolated colonies may play an important role in the “replication crisis.” In a more positive light, divergent rodent colonies represent an opportunity to leverage genetically distinct individuals in genetic crossing experiments. In sum, awareness of the genetic diversity of an animal colony is paramount as it allows researchers to properly replicate experiments and also to capitalize on other genetically distinct individuals to explore the genetic basis of a trait. PMID:29242387

  10. Adaptation for rodent pollination in Leucospermum arenarium (Proteaceae) despite rapid pollen loss during grooming.

    Science.gov (United States)

    Johnson, Christopher Michael; Pauw, Anton

    2014-05-01

    Plants are adapted for rodent pollination in diverse and intricate ways. This study explores an extraordinary example of these adaptations in the pincushion Leucospermum arenarium (Proteaceae) from South Africa. Live trapping and differential exclusion experiments were used to test the role of rodents versus birds and insects as pollinators. To explore the adaptive significance of geoflory, inflorescences were raised above ground level and seed production was compared. Captive rodents and flowers with artificial stigmas were used to test the effect of grooming on the rate of pollen loss. Microscopy, nectar composition analysis and manipulative experiments were used to investigate the bizarre nectar production and transport system. Differential exclusion of rodents, birds and insects demonstrated the importance of rodents in promoting seed production. Live trapping revealed that hairy-footed gerbils, Gerbillurus paeba, and striped field mice, Rhabdomys pumilio, both carried L. arenarium pollen on their forehead and rostrum, but much larger quantities ended up in faeces as a result of grooming. Terrarium experiments showed that grooming exponentially diminished the pollen loads that they carried. The nectar of L. arenarium was found to be unusually viscous and to be presented in a novel location on the petal tips, where rodents could access it without destroying the flowers. Nectar was produced inside the perianth, but was translocated to the petal tips via capillary ducts. In common with many other rodent-pollinated plants, the flowers are presented at ground level, but when raised to higher positions seed production was not reduced, indicating that selection through female function does not drive the evolution of geoflory. Despite the apparent cost of pollen lost to grooming, L. arenarium has evolved remarkable adaptations for rodent pollination and provides the first case of this pollination system in the genus.

  11. Wild Rodent Ectoparasites Collected from Northwestern Iran

    Directory of Open Access Journals (Sweden)

    Zabihollah Zarei

    2017-04-01

    Full Text Available Background: Rodents play an important role as reservoir of some pathogens, and the host of some ectoparasites as well. These ectoparasites can transmit rodents’ pathogens to human or animals. The aim of this study was to assess the distribution and infestation load of ectoparasites on rodents in Meshkin-Shahr District, northwestern Iran.Method: Rodents were captured using baited live traps in spring 2014 from Meshkin-Shahr District and were trans­ferred to the laboratory for identification to the species level. Their ectoparasites were collected, mounted and identi­fied.Results: Three rodent species including Meriones persicus (74%, Mus musculus (16.9% and Cricetulus migrato­rius (9% were identified. Among all rodents, 185 specimens (90.69% were infested with a total of 521 ectopara­sites. Overall, 10 arthropods species were collected, including fleas (97.6%, one mite (1.6% and one louse species (0.6% as follows: Xenopsylla nubica, X. astia, X. buxtoni, X. cheopis, Nosopsyllus fasciatus, N. iranus, Cten­ocephalides felis, Ctenophthalmus rettigismiti, Ornithonyssus sp and one species of genus Polyplax. The most prev­alent ectoparasites species was X. nubica (89%.Conclusion: Nearly all rodent species were infested with Xenopsylla species. Monitoring of ectoparasites on infested rodents is very important for awareness and early warning towards control of arthropod-borne diseases.

  12. Hantavirus Immunology of Rodent Reservoirs: Current Status and Future Directions

    Directory of Open Access Journals (Sweden)

    Tony Schountz

    2014-03-01

    Full Text Available Hantaviruses are hosted by rodents, insectivores and bats. Several rodent-borne hantaviruses cause two diseases that share many features in humans, hemorrhagic fever with renal syndrome in Eurasia or hantavirus cardiopulmonary syndrome in the Americas. It is thought that the immune response plays a significant contributory role in these diseases. However, in reservoir hosts that have been closely examined, little or no pathology occurs and infection is persistent despite evidence of adaptive immune responses. Because most hantavirus reservoirs are not model organisms, it is difficult to conduct meaningful experiments that might shed light on how the viruses evade sterilizing immune responses and why immunopathology does not occur. Despite these limitations, recent advances in instrumentation and bioinformatics will have a dramatic impact on understanding reservoir host responses to hantaviruses by employing a systems biology approach to identify important pathways that mediate virus/reservoir relationships.

  13. Influencia de los pares en la manifestación del bullying en estudiantes de secundaria en Arequipa Metropolitana

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    Filiberto Bellido

    2016-06-01

    Full Text Available RESUMEN: El objetivo del presente estudio fue determinar el grado de influencia que ejerce la cercanía de los alumnos de secundaria con pares que transgreden normas, sobre el rol que asumen estos alumnos dentro del bullying (agresor, víctima o espectador en el área metropolitana de la ciudad de Arequipa, teniendo en cuenta sexo y grado de instrucción. Se evaluó a 3979 estudiantes de educación secundaria de colegios estatales, privados y paraestatales de 19 distritos de la provincia de Arequipa, con edades comprendidas entre 11 y 19 años. Se realizó un análisis descriptivo y de regresión lineal múltiple y logística binaria para modelar la asociación entre variables. Los resultados muestran una mayor tendencia de los varones hacia las conductas agresivas y a asumir roles de “bully”. La influencia de pares transgresores de normas favorece en mayor grado la práctica de roles de agresor o víctima. En cuanto a la frecuencia de bullying, existe una alta prevalencia de agresores y víctimas entre los encuestados, cercana a la mitad de la muestra, mientras que la otra parte corresponde a los espectadores ya sean estos reforzadores del bullying o prosociales. ABSTRACT: The aim of this study was to determine the degree of influence of the proximity of high school students with peers who break rules on the role assumed these students within the bullying (bully, victim or viewer in the metropolitan area of ​​the city Arequipa, considering sex and level of education. We evaluated 3979 high school students from state, private and parastatal schools in 19 districts in the province of Arequipa, aged between 11 and 19 years. A descriptive and binary logistic regression and multiple linear analysis was performed to model the association between variables. The results show a greater tendency of men to aggressive behavior and assume roles of "bully". The influence of offenders pairs of rules favors greater practical role of aggressor or victim

  14. Norma percibida de consumo de marihuana en los pares de estudiantes universitarios Norma percebida de consumo de maconha sobre os pares de estudantes universitários Perceived norm for marijuana use among university student peers

    Directory of Open Access Journals (Sweden)

    Angélica Cazenave

    2009-01-01

    Full Text Available En este estudio se describe la relación entre la norma percibida del consumo de marihuana en los pares y el consumo real informado por alumnos de una universidad chilena. Se trata de un estudio cuantitativo, multicéntrico y transversal. Participaron 449 estudiantes previa firma del consentimiento informado. La información se recolectó con un cuestionario autoaplicado y se analizó con el programa SPSS 15.0. Fue encontrado que la mayoría son mujeres solteras, entre 20 y 21 años de edad, estudiantes de enfermería y educación. La norma percibida fue mayor que la de estudios nacionales (32,1% versus 21%; también el consumo autoinformado fue mayor que el nacional (32,1% versus 5,6%. Se observa un mayor consumo entre las mujeres, en educación y enfermería. Se confirma la feminización del consumo; el inicio del consumo en la universidad, el uso recreativo y la mayor tolerancia al consumo en los pares. Existe una sobreestimación del consumo de marihuana, lo que de acuerdo a la Teoría de las Normas Sociales y de Normalización influye en el aumento del consumo. Esta investigación constituye un aporte a las políticas de la salud del país y de la universidad.Descreve-se, aqui, a relação entre norma percebida de consumo de maconha entre os pares e consumo reportado em alunos de uma universidade chilena. Este é um estudo quantitativo, multicêntrico, transversal. Participaram 449 estudantes, com livre consentimento. As informações foram coletadas mediante questionário autoaplicado e analisadas através do programa SPSS 15.0. RESULTADOS: a maioria são mulheres, solteiras, entre 20 e 21 anos, estudantes de enfermagem e educação. A norma percebida é maior do que nos estudos nacionais (32,1% vs 21% e maior do que o consumo autorreportado (32,1% vs 5,6%. Observa-se maior consumo nas mulheres, e dos cursos de educação e de enfermagem. Confirma-se a feminização do consumo, o qual se inicia na universidade, por uso recreativo, e haver

  15. Tactile learning in rodents: Neurobiology and neuropharmacology.

    Science.gov (United States)

    Roohbakhsh, Ali; Shamsizadeh, Ali; Arababadi, Mohammad Kazemi; Ayoobi, Fateme; Fatemi, Iman; Allahtavakoli, Mohammad; Mohammad-Zadeh, Mohammad

    2016-02-15

    Animal models of learning and memory have been the subject of considerable research. Rodents such as mice and rats are nocturnal animals with poor vision, and their survival depends on their sense of touch. Recent reports have shown that whisker somatosensation is the main channel through which rodents collect and process environmental information. This review describes tactile learning in rodents from a neurobiological and neuropharmacological perspective, and how this is involved in memory-related processes. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Population response of rodents to control with rodenticides

    Directory of Open Access Journals (Sweden)

    A.V. TCHABOVSKY

    2009-04-01

    Full Text Available We summarize theoretical approaches and practice of rodent pest control in Russia and former USSR during last 50 years. We review literature as well as original data to understand mechanisms of rodent populations recovery after chemical control campaigns in urban areas, agricultural lands and natural foci of plague. Laboratory and field experiments indicate that inherent individual variation in behavioural, physiological and life-history traits provides survival of heterogeneous mix of individuals in residual population with increased resistance to poisonous baits and high reproductive potential that leads to fast recovery of a population. In a series of field experiments with various rodent and lagomorph species (Mus musculus, Rattus norvegicus, Meriones unguiculatus, M.meridianus, M.tamariscinus, Ochotona pallasii we have shown that patterns of recolonization of depopulated area and mechanisms of population recovery vary among species and depend on species-specific social organization. After control territorial and group-living species demonstrated an increase in mobility and affiliative and marking behaviour and a decrease in intraspecific aggression. The rate of recolonization of treated areas was high due to redistribution of survived individuals and immigration by neighbors. Population recovered to original level due to increased breeding performance and fecundity of both survived residents and immigrants. In contrast, socially-independent species exhibited minor changes in behaviour. Recolonization was mainly due to better survival and recruitment of youngs, so the rate of recolonization was low. Species-specificity of behavioural compensation mechanisms to control should be considered when developing ecologically based rodent management strategies.

  17. Miniature wireless recording and stimulation system for rodent behavioural testing

    Science.gov (United States)

    Pinnell, R. C.; Dempster, J.; Pratt, J.

    2015-12-01

    Objective. Elucidation of neural activity underpinning rodent behaviour has traditionally been hampered by the use of tethered systems and human involvement. Furthermore the combination of deep-brain stimulation (DBS) and various neural recording modalities can lead to complex and time-consuming laboratory setups. For studies of this type, novel tools are required to drive forward this research. Approach. A miniature wireless system weighing 8.5 g (including battery) was developed for rodent use that combined multichannel DBS and local-field potential (LFP) recordings. Its performance was verified in a working memory task that involved 4-channel fronto-hippocampal LFP recording and bilateral constant-current fimbria-fornix DBS. The system was synchronised with video-tracking for extraction of LFP at discrete task phases, and DBS was activated intermittently at discrete phases of the task. Main results. In addition to having a fast set-up time, the system could reliably transmit continuous LFP at over 8 hours across 3-5 m distances. During the working memory task, LFP pertaining to discrete task phases was extracted and compared with well-known neural correlates of active exploratory behaviour in rodents. DBS could be wirelessly activated/deactivated at any part of the experiment during EEG recording and transmission, allowing for a seamless integration of this modality. Significance. The wireless system combines a small size with a level of robustness and versatility that can greatly simplify rodent behavioural experiments involving EEG recording and DBS. Designed for versatility and simplicity, the small size and low-cost of the system and its receiver allow for enhanced portability, fast experimental setup times, and pave the way for integration with more complex behaviour.

  18. Comparison of measurement methods with a mixed effects procedure accounting for replicated evaluations (COM3PARE): method comparison algorithm implementation for head and neck IGRT positional verification.

    Science.gov (United States)

    Roy, Anuradha; Fuller, Clifton D; Rosenthal, David I; Thomas, Charles R

    2015-08-28

    Comparison of imaging measurement devices in the absence of a gold-standard comparator remains a vexing problem; especially in scenarios where multiple, non-paired, replicated measurements occur, as in image-guided radiotherapy (IGRT). As the number of commercially available IGRT presents a challenge to determine whether different IGRT methods may be used interchangeably, an unmet need conceptually parsimonious and statistically robust method to evaluate the agreement between two methods with replicated observations. Consequently, we sought to determine, using an previously reported head and neck positional verification dataset, the feasibility and utility of a Comparison of Measurement Methods with the Mixed Effects Procedure Accounting for Replicated Evaluations (COM3PARE), a unified conceptual schema and analytic algorithm based upon Roy's linear mixed effects (LME) model with Kronecker product covariance structure in a doubly multivariate set-up, for IGRT method comparison. An anonymized dataset consisting of 100 paired coordinate (X/ measurements from a sequential series of head and neck cancer patients imaged near-simultaneously with cone beam CT (CBCT) and kilovoltage X-ray (KVX) imaging was used for model implementation. Software-suggested CBCT and KVX shifts for the lateral (X), vertical (Y) and longitudinal (Z) dimensions were evaluated for bias, inter-method (between-subject variation), intra-method (within-subject variation), and overall agreement using with a script implementing COM3PARE with the MIXED procedure of the statistical software package SAS (SAS Institute, Cary, NC, USA). COM3PARE showed statistically significant bias agreement and difference in inter-method between CBCT and KVX was observed in the Z-axis (both p - value<0.01). Intra-method and overall agreement differences were noted as statistically significant for both the X- and Z-axes (all p - value<0.01). Using pre-specified criteria, based on intra-method agreement, CBCT was deemed

  19. Test of Fruit Extract Pare (Momordica charantia L.) to Quality of Ejaculated Spermatozoa Mice (Mus musculus L.)

    Science.gov (United States)

    Fifendy, M.; Indriati, G.

    2018-04-01

    Pare (Momordica charantia L.) can be used in the treatment of various diseases, such as influenza, cancer, anti-inflammatory, anti-HIV, antimitotic and antifertilitas. This study aimed to determine the effect of the herbal bitter (Momordica charantia L.) to ejaculated sperm quality mice (Mus musculus L.). This research was conducted using Completely Randomized Design (CRD) with 4 treatments and 6 replications, water and fed adlibitum. First treatment is given solvent extract. Second treatments extract were given 0.2 gram, third treatment were given 0.4 gram of extracts and fourth treatment were treated exstrac 0.6 gram were orally for 30 days. After the mice decapitated, dissected and take sperm from vas deferens. Then, the sperm preparation determined using the improved Neubauer. Data were analyzed by ANOVA (Analysis of Varians). The results shoured at doses of 0,2 gram, the average sperm count was 19.89. decrease significant when compared with the control in which the average number of sperm 29.13. So with this research the effective doses to decrease sperm count and can be used as a contraception medication dosage was 0,2 gram. It can be conclude that the extract of bitter (Momordica charantia L.) can decrease the quality of the ejaculated sperm of mice (Mus musculus L.)

  20. Rotura de la pared libre del ventrículo izquierdo secundaria a infarto agudo de miocardio

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    Claudio Solís

    2009-01-01

    Full Text Available RESUMENAunque la terapia trombolítica y la angioplastia primaria han cambiado radicalmente elmanejo, la evolución y el pronóstico del infarto agudo de miocardio, la rotura de la paredlibre del ventrículo izquierdo todavía implica una tasa elevada de mortalidad.Si bien la mayoría de los pacientes con esta complicación presentan un cuadro agudo ycatastrófico, que se caracteriza por taponamiento cardíaco, disociación electromecánica ymuerte en pocos minutos, aproximadamente un tercio de ellos tienen una evolución subagudacon hipotensión sostenida y diversos grados de derrame pericárdico, lo que posibilita laimplementación de medidas terapéuticas necesarias como puente al tratamiento quirúrgicoresolutivo.En este trabajo se presenta una revisión actualizada de las características clínicas yecocardiográficas de los pacientes con rotura de la pared libre del ventrículo izquierdo asociadacon infarto agudo de miocardio, con el objetivo de destacar los puntos clave del diagnóstico e incrementar la sospecha clínica de una entidad grave, no siempre fatal.REV ARGENT CARDIOL 2009;77:395-404.

  1. The parent-adolescent relationship education (PARE) program: a curriculum for prevention of STDs and pregnancy in middle school youth.

    Science.gov (United States)

    Lederman, Regina P; Mian, Tahir S

    2003-01-01

    The Parent-Adolescent Relationship Education (PARE) Program, designed for parents and middle school students, focuses on strengthening family communication about sexual issues and behaviors to help prevent teen pregnancy, human immunodeficiency virus (HIV), and other sexually transmitted diseases (STDs). The program includes content about reproduction, STDs and Acquired Immune Deficiency Syndrome (AIDS), contraception, sex risks, and safe-sex behaviors. The course uses social learning and cognitive behavioral concepts to enhance decision-making, refusal, and resistance skills. A randomized treatment or control group design is used to assign parent-child dyads to an experimental education group (social learning) or an attention-control group (traditional didactic teaching). Three post-program maintenance or booster sessions are held at 6-month intervals and at times prior to peak teen conception periods to reinforce the knowledge and skills learned. Pre- and posttests for parents and students assess group differences in parental involvement and communication, contraception, sex attitudes and intentions, sex behaviors (initiation of sexual intercourse, frequency, number of partners, contraceptive practices, refusal skills), and the incidence of pregnancy.

  2. Network Analysis of Rodent Transcriptomes in Spaceflight

    Science.gov (United States)

    Ramachandran, Maya; Fogle, Homer; Costes, Sylvain

    2017-01-01

    Network analysis methods leverage prior knowledge of cellular systems and the statistical and conceptual relationships between analyte measurements to determine gene connectivity. Correlation and conditional metrics are used to infer a network topology and provide a systems-level context for cellular responses. Integration across multiple experimental conditions and omics domains can reveal the regulatory mechanisms that underlie gene expression. GeneLab has assembled rich multi-omic (transcriptomics, proteomics, epigenomics, and epitranscriptomics) datasets for multiple murine tissues from the Rodent Research 1 (RR-1) experiment. RR-1 assesses the impact of 37 days of spaceflight on gene expression across a variety of tissue types, such as adrenal glands, quadriceps, gastrocnemius, tibalius anterior, extensor digitorum longus, soleus, eye, and kidney. Network analysis is particularly useful for RR-1 -omics datasets because it reinforces subtle relationships that may be overlooked in isolated analyses and subdues confounding factors. Our objective is to use network analysis to determine potential target nodes for therapeutic intervention and identify similarities with existing disease models. Multiple network algorithms are used for a higher confidence consensus.

  3. Rodent management: the man/environment interface

    International Nuclear Information System (INIS)

    Jackson, W.B.

    1978-01-01

    Rodents which interact with man generally are regarded as undesirable. Attempts at eliminating such rodents by increasing predation (including traps, microbiological agents, toxicants) have been relatively unsuccessful. Management by environmental manipulation must be basic. This then can be supplemented with predation at critical points where public health, use practices, or imperfections in the system demand. Society mores, practices, and economic considerations also have significant impact on the management system

  4. Caracterización de las ?-1,3-glucanosil-transferasas de la familia GH72 implicadas en la remodelación de la pared celular de Schizosaccharomyces pombe

    OpenAIRE

    Medina Redondo, María de

    2008-01-01

    La formación de la pared celular de Schizosaccharomyces pombe requiere la actividad coordinada de enzimas involucradas en la biosíntesis y modificación de sus componentes, entre los que destacan por su abundancia los glucanos. El complejo enzimático ?-glucán-sintasa sintetiza ?-1,3-glucanos lineales, que permanecen desorganizados y solubles en álcali hasta que se establecen enlaces covalentes entre los ?-1,3-glucanos y otros componentes de la pared celular. Las transferasas de la pared celula...

  5. Sexual selection halts the relaxation of protamine 2 among rodents.

    Directory of Open Access Journals (Sweden)

    Lena Lüke

    Full Text Available Sexual selection has been proposed as the driving force promoting the rapid evolutionary changes observed in some reproductive genes including protamines. We test this hypothesis in a group of rodents which show marked differences in the intensity of sexual selection. Levels of sperm competition were not associated with the evolutionary rates of protamine 1 but, contrary to expectations, were negatively related to the evolutionary rate of cleaved- and mature-protamine 2. Since both domains were found to be under relaxation, our findings reveal an unforeseen role of sexual selection: to halt the degree of degeneration that proteins within families may experience due to functional redundancy. The degree of relaxation of protamine 2 in this group of rodents is such that in some species it has become dysfunctional and it is not expressed in mature spermatozoa. In contrast, protamine 1 is functionally conserved but shows directed positive selection on specific sites which are functionally relevant such as DNA-anchoring domains and phosphorylation sites. We conclude that in rodents protamine 2 is under relaxation and that sexual selection removes deleterious mutations among species with high levels of sperm competition to maintain the protein functional and the spermatozoa competitive.

  6. Aspectos do pensamento estético de Bakhtin e seus pares = Aspects of the esthetic thought of Bakhtin and his peers

    Directory of Open Access Journals (Sweden)

    Faraco, Carlos Alberto

    2011-01-01

    Full Text Available Neste texto, há uma discussão dos fundamentos da filosofia estética de Mikhail Bakhtin e de seu pares do chamado Círculo de Bakhtin. Argumenta-se que o conceito de “excedente de visão” é o elo que une as ideias estéticas e éticas de Bakhtin

  7. Rejeição e vitimização por pares em crianças com deficiência intelectual e transtorno do espectro autista

    Directory of Open Access Journals (Sweden)

    Deisy Ribas Emerich

    2017-08-01

    Full Text Available Crianças com necessidades educacionais especiais, como Deficiência Intelectual (DI e Transtornos do Espectro Autista (TEA, participam cada vez mais de classes regulares. Apesar da relevância desta inclusão, tais crianças podem enfrentar dificuldades como rejeição e vitimização pelos pares. Por meio de uma revisão da literatura, o presente trabalho teve como objetivo identificar a prevalência, o impacto e os fatores associados à rejeição e vitimização em crianças com DI e TEA. A busca foi realizada nas bases de dados Web of Science, Pubmed, Medline, Lilacs e Scielo, com os descritores: rejeição por pares, vitimização por pares, deficiência intelectual, criança com deficiência e necessidades especiais, Transtorno do Espectro do Autismo e seus correlatos em inglês nas bases internacionais. Foram identificados 196 artigos, dos quais 32 preencheram os critérios de inclusão. Verificou-se elevada prevalência de vitimização e alta taxa de rejeição em relação a crianças com necessidades educacionais especiais, independentemente da idade. Déficits nas habilidades sociais e nas funções executivas, comportamento desatento e hiperativo e queixas internalizantes mostraram-se associados às dificuldades no relacionamento com os pares nessa população. Estes indicadores devem ser incluídos em programas de prevenção e/ou tratamento para viabilizar a adequada inclusão de crianças com necessidades educacionais especiais em salas de aula regulares.

  8. Efecto comparativo del tetróxido de osmio y del tetróxido de rutenio como fijadores sobre la ultraestructura de la pared celular de hongos

    Directory of Open Access Journals (Sweden)

    Orlando Torres-Fernández

    2003-06-01

    Full Text Available Al microscopio electrónico, la pared celular de los hongos es de apariencia translúcida en especímenes procesados mediante la posfijación convencional con tetróxido de osmio. La posfijación con tetróxido de rutenio reveló nuevos detalles ultraestructurales en hifas de Penicillium sp. y en levaduras de Saccharomyces cerevisiae. El aspecto más destacado fue la modificación en la transparencia de la pared celular, característica de la fijación con tetróxido de osmio. El tetróxido de rutenio permite verla como una estructura compuesta por dos o tres capas oscuras de diferente tonalidad. Se observaron también otros dos rasgos importantes: los septos en las hifas de Penicillium sp. presentaban una apariencia trilaminar y en la pared celular de las levaduras de S. cerevisiae, en etapa de gemación, se destacaban unas prolongaciones filiformes que emergían desde la capa interna y se proyectaban hacia el citoplasma. Se recomienda el uso combinado de los dos fijadores en estudios ultraestructurales de los hongos.

  9. Rodent Habitat On ISS: Spaceflight Effects On Mouse Behavior

    Science.gov (United States)

    Ronca, A. E.; Moyer, E. L.; Talyansky, Y.; Padmanabhan, S.; Choi, S.; Gong, C.; Globus, R. K.

    2016-01-01

    The NASA Decadal Survey (2011), Recapturing a Future for Space Exploration: Life and Physical Sciences Research for a New Era, emphasized the importance of expanding NASA life sciences research to long duration, rodent experiments on the International Space Station (ISS). To accomplish this objective, flight hardware, operations, and science capabilities supporting mouse studies in space were developed at NASA Ames Research Center. The first flight experiment carrying mice, Rodent Research Hardware and Operations Validation (Rodent Research-1), was launched on Sept 21, 2014 in an unmanned Dragon Capsule, SpaceX4, exposing the mice to a total of 37 days in space. Ground control groups were maintained in environmental chambers at Kennedy Space Center. Mouse health and behavior were monitored for the duration of the experiment via video streaming. Here we present behavioral analysis of two groups of five C57BL/6 female adult mice viewed via fixed camera views compared with identically housed Ground Controls. Flight (Flt) and Ground Control (GC) mice exhibited the same range of behaviors, including eating, drinking, exploratory behavior, self- and allo-grooming, and social interactions at similar or greater levels of occurrence. Mice propelled themselves freely and actively throughout the Habitat using their forelimbs to push off or by floating from one cage area to another, and they quickly learned to anchor themselves using tails and/or paws. Overall activity was greater in Flt as compared to GC mice, with spontaneous ambulatory behavior including the development of organized ‘circling’ or ‘race-tracking’ behavior that emerged within the first few days of flight and encompassed the primary dark cycle activity for the remainder of the experiment. We quantified the bout frequency, duration and rate of circling with respect to characteristic behaviors observed in the varying stages of the progressive development of circling: flipping utilizing two sides of the

  10. Models and detection of spontaneous recurrent seizures in laboratory rodents

    Directory of Open Access Journals (Sweden)

    Bin Gu

    2017-07-01

    Full Text Available Epilepsy, characterized by spontaneous recurrent seizures (SRS, is a serious and common neurological disorder afflicting an estimated 1% of the population worldwide. Animal experiments, especially those utilizing small laboratory rodents, remain essential to understanding the fundamental mechanisms underlying epilepsy and to prevent, diagnose, and treat this disease. While much attention has been focused on epileptogenesis in animal models of epilepsy, there is little discussion on SRS, the hallmark of epilepsy. This is in part due to the technical difficulties of rigorous SRS detection. In this review, we comprehensively summarize both genetic and acquired models of SRS and discuss the methodology used to monitor and detect SRS in mice and rats.

  11. Translational Rodent Models for Research on Parasitic Protozoa-A Review of Confounders and Possibilities.

    Science.gov (United States)

    Ehret, Totta; Torelli, Francesca; Klotz, Christian; Pedersen, Amy B; Seeber, Frank

    2017-01-01

    Rodents, in particular Mus musculus , have a long and invaluable history as models for human diseases in biomedical research, although their translational value has been challenged in a number of cases. We provide some examples in which rodents have been suboptimal as models for human biology and discuss confounders which influence experiments and may explain some of the misleading results. Infections of rodents with protozoan parasites are no exception in requiring close consideration upon model choice. We focus on the significant differences between inbred, outbred and wild animals, and the importance of factors such as microbiota, which are gaining attention as crucial variables in infection experiments. Frequently, mouse or rat models are chosen for convenience, e.g., availability in the institution rather than on an unbiased evaluation of whether they provide the answer to a given question. Apart from a general discussion on translational success or failure, we provide examples where infections with single-celled parasites in a chosen lab rodent gave contradictory or misleading results, and when possible discuss the reason for this. We present emerging alternatives to traditional rodent models, such as humanized mice and organoid primary cell cultures. So-called recombinant inbred strains such as the Collaborative Cross collection are also a potential solution for certain challenges. In addition, we emphasize the advantages of using wild rodents for certain immunological, ecological, and/or behavioral questions. The experimental challenges (e.g., availability of species-specific reagents) that come with the use of such non-model systems are also discussed. Our intention is to foster critical judgment of both traditional and newly available translational rodent models for research on parasitic protozoa that can complement the existing mouse and rat models.

  12. Translational Rodent Models for Research on Parasitic Protozoa—A Review of Confounders and Possibilities

    Directory of Open Access Journals (Sweden)

    Totta Ehret

    2017-06-01

    Full Text Available Rodents, in particular Mus musculus, have a long and invaluable history as models for human diseases in biomedical research, although their translational value has been challenged in a number of cases. We provide some examples in which rodents have been suboptimal as models for human biology and discuss confounders which influence experiments and may explain some of the misleading results. Infections of rodents with protozoan parasites are no exception in requiring close consideration upon model choice. We focus on the significant differences between inbred, outbred and wild animals, and the importance of factors such as microbiota, which are gaining attention as crucial variables in infection experiments. Frequently, mouse or rat models are chosen for convenience, e.g., availability in the institution rather than on an unbiased evaluation of whether they provide the answer to a given question. Apart from a general discussion on translational success or failure, we provide examples where infections with single-celled parasites in a chosen lab rodent gave contradictory or misleading results, and when possible discuss the reason for this. We present emerging alternatives to traditional rodent models, such as humanized mice and organoid primary cell cultures. So-called recombinant inbred strains such as the Collaborative Cross collection are also a potential solution for certain challenges. In addition, we emphasize the advantages of using wild rodents for certain immunological, ecological, and/or behavioral questions. The experimental challenges (e.g., availability of species-specific reagents that come with the use of such non-model systems are also discussed. Our intention is to foster critical judgment of both traditional and newly available translational rodent models for research on parasitic protozoa that can complement the existing mouse and rat models.

  13. Neurogenic inflammation in human and rodent skin

    DEFF Research Database (Denmark)

    Schmelz, M; Petersen, Lars Jelstrup

    2001-01-01

    The combination of vasodilation and protein extravasation following activation of nociceptors has been termed "neurogenic inflammation." In contrast to rodents, no neurogenic protein extravasation can be elicited in healthy human skin. Dermal microdialysis has considerably increased our knowledge...... about neurogenic inflammation in human skin, including the involvement of mast cells.......The combination of vasodilation and protein extravasation following activation of nociceptors has been termed "neurogenic inflammation." In contrast to rodents, no neurogenic protein extravasation can be elicited in healthy human skin. Dermal microdialysis has considerably increased our knowledge...

  14. Responses of nocturnal rodents to shrub encroachment in Banni grasslands, Gujarat, India

    Science.gov (United States)

    Jayadevan, A.

    2016-12-01

    Shrub encroachment is one of the greatest threats to grasslands globally. These woodlands can strongly influence the behaviour of small mammals adapted to more open habitats, which rely on high visibility for early detection of predators. In semi-arid grasslands, rodents are considered keystone species. Although shrub encroachment is known to negatively affect rodent assemblages, its impact on the foraging behaviour of rodents, which is known to vary in response to risky situations, is unknown. Understanding whether shrub encroachment alters such antipredator behaviour is important as antipredator behaviour can alter the distribution, abundance and ultimately, survival of prey species. In this study, I explored the effects of shrub encroachment on the foraging behaviour of nocturnal rodent communities in the Banni grasslands, India. I examined foraging behaviour, quantified using the giving-up density (GUD) framework and the number of rodent crossings around food patches, in two habitats that differed in the extent of shrub encroachment. Under the GUD framework, the amount of food left behind by a forager in a food patch reflects the costs of feeding at the patch. Higher GUDs imply higher foraging costs. I also investigated how removal of an invasive woody plant, Prosopis juliflora would affect foraging behaviour of nocturnal rodents. High shrub encroachment was associated with higher foraging costs (higher GUDs) and lower activity than the sparsely wooded habitat, likely due to low visibility in the densely wooded habitat. The dense habitat also supported a higher richness and relative abundance of generalist rodents than the sparse habitat, likely due to the increased heterogeneity of the habitat. The tree removal experiment revealed that rodents had lower GUDs (i.e., low foraging costs) after the event of tree cutting. This may be due to the reduction of cover in the habitat, leading to higher visibility and lower predation risk. My results suggest that shrub

  15. Análisis experimental de coeficientes de descarga en vertederos trapezoidales de pared delgada – Parte I

    Directory of Open Access Journals (Sweden)

    Josué Rodríguez Santos

    2015-12-01

    Full Text Available El propósito de esta investigación en modelos físicos reducidos para vertederos trapezoidales de pared delgada, y el análisis de aproximadamente 8000 datos de laboratorio, es generar una curva o ábaco con coeficientes de descarga en función de la relación H/B (carga de agua sobre la cresta vertedero para ancho de cresta del vertedero, coeficientes de descarga que nos permitirán estimar caudales reales que se descarga sobre estas estructuras. La presente investigación considera vertederos trapezoidales, con taludes que oscilan entre 45º y 90ºrespecto al eje horizontal, manteniendo la longitud de cresta constante en todos los vertederos. Estructuras hidrotécnicas que se emplean en la derivación y medición de caudales, control de niveles en embalses, canales, estanques, elevación del nivel de agua, evacuación de avenidas, control de caudales de infiltración en represas, etc. La ciencia de la Hidráulica a través de la experimentación en laboratorios de investigación, formula leyes fundamentales del movimiento de la misma, para la solución de problemas que se presentan en las diferentes estructuras hidrotécnicas, o a su vez la experimentación confirma aquellas leyes de origen teórico. Cabe señalar que la presente investigación considera vertederos con una sola longitud de cresta, de al menos cinco longitudes de cresta, vertederos en proceso de investigación actual. En el ábaco adjunto se presenta las curvas de los coeficientes de descarga para los vertederos trapezoidales, modelados según la geometría antes descrita, coeficientes que están en función de la relación H/B (carga de agua sobre el ancho de cresta, ábaco que será ratificado o modificado conforme avance la presente investigación.

  16. Acercando los archivos a los ciudadanos. Una experiencia desde el Portal de Archivos Españoles (PARES del Ministerio de Educación, Cultura y Deporte

    Directory of Open Access Journals (Sweden)

    Sánchez Mairena, Alfonso

    2014-02-01

    Full Text Available The Spanish Archives Portal is the third generation in the computerization of the State Archives. It is intended to provide citizens and researchers with integrated on-line access to the archival databases of the eight state general archives distributed across Spain, while facsimiles or digital versions of the documents are added to the archival description catalogue. At the same time, PARES is producing a line of tools for electronic management of the public services offered in the network of the State Archives to researchers and members of the public visiting the archive in person. And thirdly, PARES is an archival platform intended to promote the whole range of possible dissemination strategies. The platform today is fundamentally a repository for the creation, management and dissemination of historical records. However, also it is involved in a process of transformation to accommodate the concepts of “open files” and web 2.0 principles. To do this, different courses of action are being pursued such as converting PARES into an OAI-PMH repository, which allows interoperability with other archival information systems, both Spanish and international, and the development of new tools and standards for the incorporating multilingual access Points.El Portal de Archivos Españoles supone la tercera generación en la informatización de los Archivos Estatales. Está destinado a facilitar a los investigadores y a los ciudadanos el acceso integrado en red a las bases de datos archivísticas de los ocho grandes archivos de titularidad estatal distribuidos por la geografía española, al mismo tiempo que se van incorporando los facsímiles u objetos digitales de los documentos. Al mismo tiempo, PARES elabora una línea de herramientas para la gestión electrónica de los servicios públicos ofrecidos en la red de centros a los investigadores y ciudadanos que acceden presencialmente. Y en tercer lugar, PARES es una plataforma destinada a favorecer

  17. Object Recognition Memory and the Rodent Hippocampus

    Science.gov (United States)

    Broadbent, Nicola J.; Gaskin, Stephane; Squire, Larry R.; Clark, Robert E.

    2010-01-01

    In rodents, the novel object recognition task (NOR) has become a benchmark task for assessing recognition memory. Yet, despite its widespread use, a consensus has not developed about which brain structures are important for task performance. We assessed both the anterograde and retrograde effects of hippocampal lesions on performance in the NOR…

  18. BEHAVIOURAL STUDIES ON SOME RHODESIAN RODENTS

    African Journals Online (AJOL)

    behaviour, . courtship, parental and juvenile behaviour and activity patterns. ... behavioural observations were facilitated by the development of a glass-fronted ~'double-storey" cage which ..... Adolescent siblings in both single sex and mixed groups ..... Wild rodents as Laboratory Animals and their contribution to medical.

  19. Rodent malaria parasites : genome organization & comparative genomics

    NARCIS (Netherlands)

    Kooij, Taco W.A.

    2006-01-01

    The aim of the studies described in this thesis was to investigate the genome organization of rodent malaria parasites (RMPs) and compare the organization and gene content of the genomes of RMPs and the human malaria parasite P. falciparum. The release of the complete genome sequence of P.

  20. Estrategias de "Evaluación por pares" para valorar competencias transversales en estudiantes universitarios a través de Moodle

    OpenAIRE

    Morán Astorga, María Consuelo; Urchaga Litago, J. David; Rodríguez Escanciano, Susana; Fínez Silva, María José; López Moya, Manuel; Martínez Barroso, María Reyes; López Diez, Carlos

    2015-01-01

    Uno de los retos que se presentan en la educación universitaria es el diseño de estrategias de evaluación acordes a las demandas planteadas en el Espacio Europeo de Educación Superior (EEES). Este EEES establece que el alumno sea agente activo, también en el proceso de evaluación y que tenga una mayor capacidad de asumir responsabilidades en el mismo. Existen diferentes modalidades de participación del alumnado universitario en la evaluación, siendo la evaluación por pares u...

  1. Ingeniería de tejidos y cirugía de la pared abdominal: prototipo de bioprótesis

    OpenAIRE

    Brandi, Claudio; Ambrosis, Mariana; Barraud, Carlos; Argibay, Pablo

    2013-01-01

    Antecedentes: La tendencia actual es reparar los defectos de la pared abdominal con mallas de polipropileno (PP) Este polímero tiene buena resistencia a las presiones intraabdominales, sin embargo puede presentar adherencias intestinales e infección. Con la idea de evitar estas complicaciones surge el desarrollo de mallas biológicas. Éstas están compuestas de colágeno descelularizado obtenido de tejido conectivo porcino, bovino o humano. Una posibilidad actual es cultivar células madres mesen...

  2. Fatores da família e da escola sobre o desenvolvimento de habilidades sociais e comportamentos agressivos entre pares na infância

    OpenAIRE

    Giovanna Wanderley Petrucci Toscano

    2014-01-01

    O objetivo geral desta dissertação foi investigar o efeito de fatores da família e da escola sobre as habilidades sociais e os comportamentos agressivos entre pares na infância. Foram realizados um estudo teórico e três estudos empíricos. O estudo teórico consistiu numa revisão não sistemática da literatura que demonstrou o papel da qualidade dos relacionamentos pais-criança e professor-aluno e do clima escolar sobre o desenvolvimento socioemocional na infância. O segundo estudo apresentou os...

  3. Termodinámica de Sistemas Metálicos (II. Extensión y Refinamiento de Los Modelos Energéticos de Pares

    Directory of Open Access Journals (Sweden)

    J. Valderrama N.

    2009-07-01

    Full Text Available Se analizan k>s posibles refinamientos de los modelos de pares aplicados a soluciones metálicas liquidas. Como una extensión de los mismos se discute el tratamiento estadístico de Takeuchi y se presenta su aplicación a los sistemas Ag-Ge, Ag-Sn, Cu-ln y Cd-Cu. Cd-Sb, St>- Zn, El comportamiento de mini- estructuras en estos sistemas es también bien presentado y discutido.

  4. Percepción de la creatividad en niños, padres y pares: efectos en la producción creativa

    Directory of Open Access Journals (Sweden)

    Gabriela Krumm

    2015-01-01

    Full Text Available Objetivo . El presente estudio tuvo como objetivo evaluar la percepción de la creatividad en niños, padres y pares, y el efecto de estas percepciones sobre la producción creativa de los niños en actividades de papel y lápiz. Método. Participaron 359 alumnos de 9 a 13 años de diferentes escuelas y colegios de la provincia de Entre Ríos de la República Argentina. Para conocer la producción creativa, los niños completaron la prueba de figuras del Test de Pensamiento Creativo de Torrance Forma B. Para estudiar la valoración de los pares, padres y niños sobre la creatividad se aplicó el Sociograma “Compañero creativo”, la Escala de Personalidad Creadora (versión heteroevaluación a los padres o tutores y la versión autoevaluación a los niños de 11 a 13 años. Resultados. Los resultados mostraron que tanto la percepción parental ( F (2, 356 = 6.55, p = 0.002, así como la evaluación que realizan los pares ( F (2, 356 = 4.90, p = 0.008 sobre la creatividad mejoran la producción creativa del niño en las tareas de papel y lápiz. No se encontraron diferencias significativas en la producción creativa según la evaluación del niño sobre su propia creatividad. Conclusión. Los datos muestran la importancia cardinal de los factores contextuales, particularmente, la percepción de los padres y de los pares en los procesos de formación del yo en cuanto a las competencias y habilidades que son necesarias para realizar una actividad creadora.

  5. Dietary patterns of two herbivorous rodents: and Parotomys brantsii ...

    African Journals Online (AJOL)

    Frequency of occurrence of plant species in the diets were compared with availability of the plants in the rodents' habitats. Both rodents are generalist herbivores, eating plants species in proportion to the availability in their habitats. Dietary patterns, diversity of diet and degree of overlap between rodent's diets are a function ...

  6. Advances in Rodent Research Missions on the International Space Station

    Science.gov (United States)

    Choi, S. Y.; Ronca, A.; Leveson-Gower, D.; Gong, C.; Stube, K.; Pletcher, D.; Wigley, C.; Beegle, J.; Globus, R. K.

    2016-01-01

    A research platform for rodent experiment on the ISS is a valuable tool for advancing biomedical research in space. Capabilities offered by the Rodent Research project developed at NASA Ames Research Center can support experiments of much longer duration on the ISS than previous experiments performed on the Space Shuttle. NASAs Rodent Research (RR)-1 mission was completed successfully and achieved a number of objectives, including validation of flight hardware, on-orbit operations, and science capabilities as well as support of a CASIS-sponsored experiment (Novartis) on muscle atrophy. Twenty C57BL6J adult female mice were launched on the Space-X (SpX) 4 Dragon vehicle, and thrived for up to 37 days in microgravity. Daily health checks of the mice were performed during the mission via downlinked video; all flight animals were healthy and displayed normal behavior, and higher levels of physical activity compared to ground controls. Behavioral analysis demonstrated that Flight and Ground Control mice exhibited the same range of behaviors, including eating, drinking, exploratory behavior, self- and allo-grooming, and social interactions indicative of healthy animals. The animals were euthanized on-orbit and select tissues were collected from some of the mice on orbit to assess the long-term sample storage capabilities of the ISS. In general, the data obtained from the flight mice were comparable to those from the three groups of control mice (baseline, vivarium and ground controls, which were housed in flight hardware), showing that the ISS has adequate capability to support long-duration rodent experiments. The team recovered 35 tissues from 40 RR-1 frozen carcasses, yielding 3300 aliquots of tissues to distribute to the scientific community in the U.S., including NASAs GeneLab project and scientists via Space Biology's Biospecimen Sharing Program Ames Life Science Data Archive. Tissues also were distributed to Russian research colleagues at the Institute for

  7. Configuração familiar, género e coping em adolescentes: papel dos pares Configuración familiar, género y el coping en adolescentes: el rol de los pares Family configuration, gender and coping in adolescents: the role of peers

    Directory of Open Access Journals (Sweden)

    Mónica Costa

    2012-12-01

    Full Text Available Relações interpessoais estabelecidas no contexto de institucionalização, nomeadamente com os pares, são fontes relevantes de suporte emocional e facilitador do processo adaptativo na fase de transição para a adultícia. O objectivo do presente estudo prende-se com a análise da qualidade da ligação de adolescentes aos pares e do seu efeito preditor nas estratégias de coping dos jovens. Pretende-se ainda testar o papel moderador da configuração familiar e do género na associação entre a ligação aos pares e as estratégias de coping. A amostra é composta por 311 adolescentes, 145 institucionalizados e 166 de famílias tradicionais, entre os 14 e os 18 anos, de ambos os géneros. A recolha de dados foi realizada através da Rosenberg Self-esteem Scale (Rosenberg, 1965, Inventory of Peer and Parental Attachment (Armsden & Greenberg, 1987 e o COPE Inventory (Carver, Weintraub & Scheider, 1989. Os resultados sugerem que a qualidade da ligação aos pares se mostra relevante na predição das estratégias de coping adaptativas (coping activo e uso de suporte social emocional.El establecimiento de las relaciones interpersonales en el contexto de la institucionalización, en particular con los pares es un importante fuente de apoyo emocional y facilitador del proceso de adaptación en la transición hacia la edad adulta. El objetivo de este estudio es el análisis de la calidad de la relación con los pares y su efecto predictivo en las estrategias de coping de los jóvenes. Otro objetivo es poner a prueba el papel moderador de la configuración familiar y el género en la asociación entre la relación con los pares y estrategias de coping. La muestra está compuesta por 311 adolescentes, 145 y 166 familias tradicionales institucionalizadas, entre 14 y 18 años, de ambos sexos. Los datos han sido recogidos con recurso al Rosenberg Self-esteem Scale (Rosenberg, 1965, Inventory of Peer and Parental Attachment (Armsden & Greenberg, 1987 y

  8. Functional organization of V2a-related locomotor circuits in the rodent spinal cord

    DEFF Research Database (Denmark)

    Dougherty, Kimberly J.; Kiehn, Ole

    2010-01-01

    Studies of mammalian locomotion have been greatly facilitated by the use of the isolated rodent spinal cord preparation that retains the locomotor circuits needed to execute the movement. Physiological and molecular genetic experiments in this preparation have started to unravel the basic circuit...

  9. Consumo de drogas entre estudantes universitários: família, espiritualidade e entretenimento moderando a influência dos pares

    Directory of Open Access Journals (Sweden)

    Maria Terezinha Zeferino

    2015-01-01

    Full Text Available Investigación cuantitativa de tipo descriptiva-exploratoria, con diseño transversal que investigado el papel de la familia, la espiritualidad y entretenimiento en la moderá a la relación entre influencia de la pares y el consumo de drogas entre estudiantes universitarios. La muestra fue conformada por 250 estudiantes de una universidad pública brasileira de forma no probabilística. Fue elaborado un cuestionario con 5 escalas ya validadas, que interrogaba sobre la influencia del grupo de pares, las relaciones familiares, el entretenimiento, la espiritualidad y el consumo de drogas. Se utilizó el programa SPSS versión 18 para el análisis estadística. Los datos indicaran que el 90,8% de los estudiantes de la muestran reportaron tener por lo menos un amigo que consumía drogas, las drogas mas consumidas fueron alcohol, tabaco y marihuana. Se estableció asociación significativa entre algunos factores académicos y culturales con el consumo de drogas legales e ilegales Se recomienda que deben ser elaboradas estrategias preventivas considerando la influencia de los factores culturales sobre el consumo de drogas entre los estudiantes universitarios.

  10. Rehabilitative Soft Exoskeleton for Rodents.

    Science.gov (United States)

    Florez, Juan Manuel; Shah, Manan; Moraud, Eduardo Martin; Wurth, Sophie; Baud, Laetitia; Von Zitzewitz, Joachim; van den Brand, Rubia; Micera, Silvestro; Courtine, Gregoire; Paik, Jamie

    2017-02-01

    Robotic exoskeletons provide programmable, consistent and controllable active therapeutic assistance to patients with neurological disorders. Here we introduce a prototype and preliminary experimental evaluation of a rehabilitative gait exoskeleton that enables compliant yet effective manipulation of the fragile limbs of rats. To assist the displacements of the lower limbs without impeding natural gait movements, we designed and fabricated soft pneumatic actuators (SPAs). The exoskeleton integrates two customizable SPAs that are attached to a limb. This configuration enables a 1 N force load, a range of motion exceeding 80 mm in the major axis, and speed of actuation reaching two gait cycles/s. Preliminary experiments in rats with spinal cord injury validated the basic features of the exoskeleton. We propose strategies to improve the performance of the robot and discuss the potential of SPAs for the design of other wearable interfaces.

  11. Leptospira interrogans in Rodents from Cape Verde.

    Science.gov (United States)

    Plata-Luis, Josué; Foronda, Pilar; Martín-Alonso, Aaron; Feliu, Carlos; Alves, Joana; Gil, Horacio; Valladares, Basilio

    2016-11-01

    Leptospirosis is an important worldwide zoonotic disease that can infect both animals and humans. In most cases, leptospirosis is a nonspecific self-limiting illness, but some patients can develop a severe form with a high mortality. This study was carried out in Santiago Island, Cape Verde, in 2012-2013. A total of 62 wild rodents (Rattus rattus and Mus domesticus) were analyzed. The lipL32 gene, present only in pathogenic Leptospira spp., was amplified by PCR, and 16 samples were positive (25.8%). In both rodent species, Leptospira interrogans was identified. The results show the presence of pathogenic Leptospira in the three localities analyzed in Santiago. The presence of L. interrogans demonstrates a serious health risk for the population, since this species has been associated with the most severe form of leptospirosis, the Weil's disease in humans, a severe infection with jaundice, renal failure, and hemorrhage.

  12. Homeobox Genes in the Rodent Pineal Gland

    DEFF Research Database (Denmark)

    Rath, Martin Fredensborg; Rohde, Kristian; Klein, David C

    2013-01-01

    The pineal gland is a neuroendocrine gland responsible for nocturnal synthesis of melatonin. During early development of the rodent pineal gland from the roof of the diencephalon, homeobox genes of the orthodenticle homeobox (Otx)- and paired box (Pax)-families are expressed and are essential...... for normal pineal development consistent with the well-established role that homeobox genes play in developmental processes. However, the pineal gland appears to be unusual because strong homeobox gene expression persists in the pineal gland of the adult brain. Accordingly, in addition to developmental...... functions, homeobox genes appear to be key regulators in postnatal phenotype maintenance in this tissue. In this paper, we review ontogenetic and phylogenetic aspects of pineal development and recent progress in understanding the involvement of homebox genes in rodent pineal development and adult function...

  13. Neurogenetics of aggressive behavior: studies in rodents.

    Science.gov (United States)

    Takahashi, Aki; Miczek, Klaus A

    2014-01-01

    Aggressive behavior is observed in many animal species, such as insects, fish, lizards, frogs, and most mammals including humans. This wide range of conservation underscores the importance of aggressive behavior in the animals' survival and fitness, and the likely heritability of this behavior. Although typical patterns of aggressive behavior differ between species, there are several concordances in the neurobiology of aggression among rodents, primates, and humans. Studies with rodent models may eventually help us to understand the neurogenetic architecture of aggression in humans. However, it is important to recognize the difference between the ecological and ethological significance of aggressive behavior (species-typical aggression) and maladaptive violence (escalated aggression) when applying the findings of aggression research using animal models to human or veterinary medicine. Well-studied rodent models for aggressive behavior in the laboratory setting include the mouse (Mus musculus), rat (Rattus norvegicus), hamster (Mesocricetus auratus), and prairie vole (Microtus ochrogaster). The neural circuits of rodent aggression have been gradually elucidated by several techniques, e.g., immunohistochemistry of immediate-early gene (c-Fos) expression, intracranial drug microinjection, in vivo microdialysis, and optogenetics techniques. Also, evidence accumulated from the analysis of gene-knockout mice shows the involvement of several genes in aggression. Here, we review the brain circuits that have been implicated in aggression, such as the hypothalamus, prefrontal cortex (PFC), dorsal raphe nucleus (DRN), nucleus accumbens (NAc), and olfactory system. We then discuss the roles of glutamate and γ-aminobutyric acid (GABA), excitatory and inhibitory amino acids in the brain, as well as their receptors, in controlling aggressive behavior, focusing mainly on recent findings. At the end of this chapter, we discuss how genes can be identified that underlie individual

  14. Estudio de la variación de la composición de los polisacáridos contenidos en la pared celular de la levadura Saccharomyces Cerevisiae

    OpenAIRE

    B. Aguilar Uscanga; J. Solis Pacheco; J. François

    2005-01-01

    La pared celular de levaduras representa entre 20 a 30 % de la célula en peso seco. Está compuesta de polisacáridos complejos de β-glucanos, manoproteínas y quitina. Se estudió la composición de los polisacáridos contenidos en la pared celular de la Saccharomyces cerevisiae CEN.PK 113 y se observó el efecto de la variación de la fuente carbono (glucosa, sacarosa, galactosa, maltosa, manosa, etanol) y pH (3, 4, 5, 6) en un medio mineral cell factory. Las células fueron recolectad...

  15. COMPORTAMIENTO ANTIARRÍTMICO DE LA HIPOXIA EN SIMULACIONES DE PARED TRANSMURAL CARDÍACA EN PRESENCIA DE ISQUEMIA SUB-EPICÁRDICA

    Directory of Open Access Journals (Sweden)

    Oscar Henao Gallo

    2011-01-01

    Full Text Available

    RESUMEN 

    El papel preponderante de la corriente de potasio sensitiva a Adenosin Trifosfato y su contribución a cambios electrofi siológicos que ocurren durante heterogeneidades y alteraciones fisicoquímicas debido a isquemia en la pared transmural cardíaca son aún debatidos. El objetivo de este trabajo fue estudiar la infl uencia de la activación de la hipoxia en la desestabilización del frente de onda eléctrico en pared transmural heterogénea en presencia de isquemia subepicárdica en un modelo computacional de tejido virtual. La taquicardia polimórfi ca obtenida de las simulaciones muestra que la activación de la hipoxia presenta un comportamiento antiarrítmico. La hiperkalemia es el principal agente capaz de generar bloqueo de conducción y alteraciones del segmento TQ y el segmento ST en los electrogramas obtenidos.

     

    Palabras clave: Electrogramas, hipoxia, isquemia, modelo Luo-Rudy, pared transmural heterogénea, reentrada espiral, taquicardia ventricular polimórfica.

     

    ABSTRACT

     

    ANTIARRHYTHMIC BEHAVIOR OF HYPOXIA IN CARDIAC TRANSMURAL WALL SIMULATIONS IN PRESENCE OF SUB-EPICARDIC ISCHEMIA

    The role of potassium adenosine triphosphate sensitive fl ow and its contributions to electrophysiological changes that occur during chemical-physical alterations and heterogeneities due to ischemia in cardiac transmural wall is still debated.

     

    The aim of this work was to study hypoxia activation influence in wavefront electric disturbance in heterogeneous transmural wall subjected to sub-epicardial ischemia, using a virtual tissue computational model. Polymorphic tachycardia obtained

  16. Reconstrucción de las secuelas de la pared abdominal en pacientes con extrofia de cloaca Reconstruction of abdominal wall sequelae in patients with cloacal extrophy

    Directory of Open Access Journals (Sweden)

    P. Iwanyk

    2009-06-01

    Full Text Available Los defectos abdominales congénitos de la línea media inferior, como la extrofia cloacal, se producen por fallos en el mesodermo entre la región umbilical y la membrana cloacal provocando severos defectos viscerales, musculares y óseos. Los reiterados intentos para la reconstrucción de los tractos intestinal y génitourinario en este tipo de malformaciones, pueden ocasionar secuelas graves en la pared malformada. La complejidad de esta malformación y los numerosos procedimientos a los que deben ser sometidos estos pacientes, requieren de un abordaje interdisciplinario desde el inicio del tratamiento y en cada una de las etapas reconstructivas a fin de evitar, al máximo, las lesiones de los tejidos abdominales para lograr, al final, una pared adecuada. Presentamos 2 casos de reconstrucción de la pared abdominal en sendos pacientes de sexo femenino con secuelas importantes de extrofia cloacal, utilizando tejidos expandidos, colgajos musculares y complementando el tratamiento en una de las pacientes con una malla protésica. En ambos casos, y a pesar de la falta de tejido provocada por la malformación y las secuelas de múltiples cirugías, obtuvimos un buen resultado funcional y estético.Abdominal congenital defects of the middle line have their origin in developmental faults of mesoderm between the umbilical region and the cloacal membrane, originating visceral, muscular and osseous defects in the abdominal wall. Repeated attempts to reconstruct the intestinal and genitourinary tract here and in other malformations, can cause serious sequeals in the previously deformed abdominal wall. We present 2 cases of abdominal wall reconstruction in patients with serious sequelae of cloacal extrophy. Complexity of this malformation calls for an interdisciplinary treatment to avoid the severe damage that may be caused during reconstructive attempts. In spite of lack of tissue because of the malformation and the sequelae of multiple surgeries we

  17. Odor supported place cell model and goal navigation in rodents

    DEFF Research Database (Denmark)

    Kulvicius, Tomas; Tamosiunaite, Minija; Ainge, James

    2008-01-01

    Experiments with rodents demonstrate that visual cues play an important role in the control of hippocampal place cells and spatial navigation. Nevertheless, rats may also rely on auditory, olfactory and somatosensory stimuli for orientation. It is also known that rats can track odors or self......-generated scent marks to find a food source. Here we model odor supported place cells by using a simple feed-forward network and analyze the impact of olfactory cues on place cell formation and spatial navigation. The obtained place cells are used to solve a goal navigation task by a novel mechanism based on self......-marking by odor patches combined with a Q-learning algorithm. We also analyze the impact of place cell remapping on goal directed behavior when switching between two environments. We emphasize the importance of olfactory cues in place cell formation and show that the utility of environmental and self...

  18. Influência do grupo de pares e uso de drogas ilícitas entre adolescentes brasileiros: um estudo transversal

    OpenAIRE

    Kelly Oliva Jorge; Raquel Conceição Ferreira; Efigênia Ferreira e Ferreira; Ichiro Kawachi; Patrícia Maria Zarzar; Isabela Almeida Pordeus

    2018-01-01

    O estudo teve como objetivo examinar o uso de drogas ilícitas e as associações com fatores socioeconômicos e influência do grupo de pares entre adolescentes brasileiros de 15 a 19 anos de idade. Foi adotada uma amostra de clusters em dois estágios, com a seleção aleatória de escolas públicas e privadas entre os nove distritos administrativos de uma capital de estado, e a seleção aleatória de turmas em cada escola. A variável de desfecho foi o uso de drogas ilícitas, medido pela seguinte pergu...

  19. La Revisión por Pares y la Selección de Artículos para Publicación

    Directory of Open Access Journals (Sweden)

    Gladys S. Martínez

    2012-01-01

    Full Text Available La revisión de manuscritos científicos por pares evaluadores pretende evaluar la originalidad, calidad y pertinencia de datos asociados a una investigación. Con algunas variaciones, este sistema se ha institucionalizado, ha sido parte central en la validación de publicaciones científicas y es aceptado por la mayoría de científicos como la mejor opción de evaluación entre las disponibles. En este artículo se describen brevemente las fortalezas y debilidades de este sistema de evaluación y se reflexiona sobre algunas alternativas para su mejoramiento, lo cual es valioso para revistas de habla española.

  20. Socialização/interação entre pares de alunos com a Síndrome de Asperger, em contexto escolar

    OpenAIRE

    Simas, Filomena Maria Ávila e Cardoso dos Santos

    2012-01-01

    Dissertação apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências da Educação: Educação Especial, especialização em Domínio Emocional e da Personalidade A presente investigação versa a problemática de crianças referenciadas/diagnosticadas com a Síndrome de Asperger (SA), que apresentam grandes dificuldades de socialização/interação com os seus pares, ao iniciarem a escolaridade obrigatória. Perante esta problemática, os objetivo...

    1. Euthanasia using gaseous agents in laboratory rodents.

      Science.gov (United States)

      Valentim, A M; Guedes, S R; Pereira, A M; Antunes, L M

      2016-08-01

      Several questions have been raised in recent years about the euthanasia of laboratory rodents. Euthanasia using inhaled agents is considered to be a suitable aesthetic method for use with a large number of animals simultaneously. Nevertheless, its aversive potential has been criticized in terms of animal welfare. The data available regarding the use of carbon dioxide (CO2), inhaled anaesthetics (such as isoflurane, sevoflurane, halothane and enflurane), as well as carbon monoxide and inert gases are discussed throughout this review. Euthanasia of fetuses and neonates is also addressed. A table listing currently available information to ease access to data regarding euthanasia techniques using gaseous agents in laboratory rodents was compiled. Regarding better animal welfare, there is currently insufficient evidence to advocate banning or replacing CO2 in the euthanasia of rodents; however, there are hints that alternative gases are more humane. The exposure to a volatile anaesthetic gas before loss of consciousness has been proposed by some scientific studies to minimize distress; however, the impact of such a measure is not clear. Areas of inconsistency within the euthanasia literature have been highlighted recently and stem from insufficient knowledge, especially regarding the advantages of the administration of isoflurane or sevoflurane over CO2, or other methods, before loss of consciousness. Alternative methods to minimize distress may include the development of techniques aimed at inducing death in the home cage of animals. Scientific outcomes have to be considered before choosing the most suitable euthanasia method to obtain the best results and accomplish the 3Rs (replacement, reduction and refinement). © The Author(s) 2015.

    2. Competência social e autismo: o papel do contexto da brincadeira com pares Social competence and autism: the role of the context of play with peers

      Directory of Open Access Journals (Sweden)

      Cláudia Sanini

      2013-03-01

      Full Text Available Observa-se o esforço dos pesquisadores em delinear e avaliar intervenções para facilitar o desenvolvimento da interação social em crianças com autismo e seus pares, em situações de inclusão escolar. Entre os resultados controversos dos estudos estão os que se referem ao papel do contexto das brincadeiras, isto é, se livre ou dirigida, na promoção da competência social dessas crianças. O objetivo deste estudo foi revisar criticamente a literatura sobre o tema, buscando-se evidências sobre que tipo de contexto de brincadeira tende a promover as interações entre pares, examinando-se as questões metodológicas que cercam esse debate. A conclusão foi de que ambos os contextos promovem o desenvolvimento da competência social, mas o livre tende a ser mais duradouro e espontâneo.There is a substantial effort of researchers in designing and assessing interventions aiming to promote the social interaction between children with autism and their peers, in the context of inclusion. Among the results that are controversial are the issues related to the role of the play context (free or directed in the promotion of children's social competence. The aim of this study was to critically review the literature about this topic by searching evidences about what sort of play context tend to promote peer interaction and by examining the methodological issues that surround this debate. The conclusion is that both contexts promote the development of social competence, but the free one tends to be more permanent and spontaneous.

    3. A colaboração entre pares em uma turma de adolescentes aprendendo inglês na escola pública

      Directory of Open Access Journals (Sweden)

      Edcléia Aparecida BASSO

      2011-07-01

      Full Text Available Neste artigo apresentamos alguns resultados alcançados por meio de uma pesquisa-ação realizada com alunos-adolescentes de escola pública. A análise dos dados foi norteada pela teoria sociocultural, quando, então, objetivamos entender o desenvolvimento daqueles alunos pela linguagem, focalizando as interações estabelecidas entre colegas e entre professor e alunos-adolescentes. Discutimos, especificamente, o construto teórico scaffolding, no viés da colaboração entre pares em atividades orais trabalhadas em sala de aula. Escolhemos como fonte primária para o presente estudo dados coletados por meio de gravações/filmagens de aulas, selecionando e transcrevendo alguns excertos para ilustrar a análise feita. Utilizamos também o diário de campo do aluno-professor-pesquisador. Esses dados revelaram características peculiares e coerentes com a adolescência, fase pela qual os alunos passavam, tais como o desinteresse e apatia nas aulas, e apontaram também ocorrências de situações propícias à colaboração efetiva entre pares (colegas, que poderiam ter propiciado o desenvolvimento de ambos, mas que resultaram, na maioria delas, em aparente fracasso. Entretanto, ficou também evidenciado que, quando a atividade desperta a curiosidade, a motivação do aluno-adolescente, ele se sente recrutado a participar da tarefa. Encerramos o estudo, certos da necessidade de mais pesquisas e estudos na área da Línguística Aplicada que focalizem o aluno-adolescente e seu desenvolvimento pela aprendizagem de uma nova língua no contexto público.

    4. Simple, inexpensive computerized rodent activity meters.

      Science.gov (United States)

      Horton, R M; Karachunski, P I; Kellermann, S A; Conti-Fine, B M

      1995-10-01

      We describe two approaches for using obsolescent computers, either an IBM PC XT or an Apple Macintosh Plus, to accurately quantify spontaneous rodent activity, as revealed by continuous monitoring of the spontaneous usage of running activity wheels. Because such computers can commonly be obtained at little or no expense, and other commonly available materials and inexpensive parts can be used, these meters can be built quite economically. Construction of these meters requires no specialized electronics expertise, and their software requirements are simple. The computer interfaces are potentially of general interest, as they could also be used for monitoring a variety of events in a research setting.

    5. Calorie restriction in rodents: Caveats to consider.

      Science.gov (United States)

      Ingram, Donald K; de Cabo, Rafael

      2017-10-01

      The calorie restriction paradigm has provided one of the most widely used and most useful tools for investigating mechanisms of aging and longevity. By far, rodent models have been employed most often in these endeavors. Over decades of investigation, claims have been made that the paradigm produces the most robust demonstration that aging is malleable. In the current review of the rodent literature, we present arguments that question the robustness of the paradigm to increase lifespan and healthspan. Specifically, there are several questions to consider as follows: (1) At what age does CR no longer produce benefits? (2) Does CR attenuate cognitive decline? (3) Are there negative effects of CR, including effects on bone health, wound healing, and response to infection? (4) How important is schedule of feeding? (5) How long does CR need to be imposed to be effective? (6) How do genotype and gender influence CR? (7) What role does dietary composition play? Consideration of these questions produce many caveats that should guide future investigations to move the field forward. Published by Elsevier B.V.

    6. Hunting, Food Preparation, and Consumption of Rodents in Lao PDR.

      Directory of Open Access Journals (Sweden)

      Kanokwan Suwannarong

      Full Text Available A cross-sectional study was conducted in 29 villages of Khamkeuth District in Bolikhamxay Province in the Lao PDR during March to May 2013. The study aimed to determine the characteristics associated with rodent consumption and related behaviors among different ethnic groups, ages, and genders. Five-hundred-eighty-four (584 males and females from 18-50 years of age participated in this study. Half of them were Hmong (292, 50% while 152 respondents were Lao-Tai (26% or other ethnic groups (140, 24%. Most of the respondents (79.5% had farming as their main occupation. Prevalences of the studied outcomes were high: 39.9 for hunting or capturing rodents in the previous year, 77.7% for preparing rodents as food, and 86.3% for rodent consumption. Multivariable logistic regression analysis showed that likelihood of these types of rodent contact was more consistently associated with behavioral factors (gathering things from the forest and elsewhere, cultivation-related activities, and taking measures to prevent rodent-borne disease than with socio-demographic, environmental, or cultural factors. The strongest associations were observed for gathering things; these associations were consistently positive and statistically significant. Although this study did not directly assess rodent-borne zoonosis risk, we believe that study findings raise concern that such risk may be substantial in the study area and other similar areas. Further epidemiological studies on the association between rodent-borne disease infection and rodent hunting, preparation for food, and consumption are recommended. Moreover, further studies are needed on the association between these potential exposure factors (i.e., rodent hunting, preparation for food, and consumption and rodent-borne infections, especially among ethnic groups like the Hmong in Lao PDR and those in neighboring countries with similar socio-demographic, environmental, behavioral and cultural contexts.

    7. Visual Landmarks Facilitate Rodent Spatial Navigation in Virtual Reality Environments

      Science.gov (United States)

      Youngstrom, Isaac A.; Strowbridge, Ben W.

      2012-01-01

      Because many different sensory modalities contribute to spatial learning in rodents, it has been difficult to determine whether spatial navigation can be guided solely by visual cues. Rodents moving within physical environments with visual cues engage a variety of nonvisual sensory systems that cannot be easily inhibited without lesioning brain…

    8. Population dynamics of Rodents and Insectivores in lowland tropical ...

      African Journals Online (AJOL)

      The community structure of rodents and insectivores in the lowland tropical rainforest of Okomu National Park, Edo State, Nigeria was assessed using a combination of live-trapping and sighting techniques during the dry and wet seasons. Seventeen species (14 species of rodent, 3 species of insectivores) were captured, ...

    9. Early Eocene rodents (Mammalia) from the Subathu Formation of ...

      Indian Academy of Sciences (India)

      1997a, b). Most of the rodents from this stratigraphic level have been referred to a rather diverse family Cha- pattimyidae ... Herein we describe a new early Eocene rodent assemblage .... thick zone of brownish red shales that occur as a ..... 1997b;. Plate 3, figure 31). ...... northwestern Pakistan and remarks on the collision.

    10. Ecology of rodents at an old quarry in Zambia

      African Journals Online (AJOL)

      Ecology of rodents at an old quarry in Zambia. E.N. Chidumayo. Livingstone Museum, Zambia. An old quarry, 2,5 hain size near Livingstone in southern. Zambia was kill- and live-trapped between September 1974 and December 1976 to determine ecological relations among. rodent species inhabiting it. Seven species ...

    11. Public Health and Rodents: A Game of Cat and Mouse

      NARCIS (Netherlands)

      Meerburg, B.G.

      2015-01-01

      Rodents are the most abundant order of living mammals, distributed on every continent except Antarctic and represent 43 % of all mammalian species. Beside causing food losses and infrastructural damage, rodents can harbour pathogens that may cause serious problems to human and animal health.

    12. Towards sustainable management of rodents in organic animal husbandry

      NARCIS (Netherlands)

      Meerburg, B.G.; Bonde, M.; Brom, F.W.A.; Endepols, S.; Jensen, A.N.; Leirs, H.; Lodal, J.; Singleton, G.R.; Pelz, H.J.; Rodenburg, T.B.; Kijlstra, A.

      2004-01-01

      From 26 to 28 May 2004 an international seminar was held in Wageningen, the Netherlands, about current knowledge and advice on rodent management on organic pig and poultry farms in Western Europe. This paper summarizes the discussions. Rodent management is necessary to protect the food production

    13. Medial prefrontal cortex role in recognition memory in rodents.

      Science.gov (United States)

      Morici, Juan Facundo; Bekinschtein, Pedro; Weisstaub, Noelia V

      2015-10-01

      The study of the neurobiology of recognition memory, defined by the integration of the different components of experiences that support recollection of past experiences have been a challenge for memory researches for many years. In the last twenty years, with the development of the spontaneous novel object recognition task and all its variants this has started to change. The features of recognition memory include a particular object or person ("what"), the context in which the experience took place, which can be the arena itself or the location within a particular arena ("where") and the particular time at which the event occurred ("when"). This definition instead of the historical anthropocentric one allows the study of this type of episodic memory in animal models. Some forms of recognition memory that require integration of different features recruit the medial prefrontal cortex. Focusing on findings from spontaneous recognition memory tasks performed by rodents, this review concentrates on the description of previous works that have examined the role that the medial prefrontal cortex has on the different steps of recognition memory. We conclude that this structure, independently of the task used, is required at different memory stages when the task cannot be solved by a single item strategy. Copyright © 2015 Elsevier B.V. All rights reserved.

    14. Epidemiology of Leptospira Transmitted by Rodents in Southeast Asia

      Science.gov (United States)

      Mielcarek, Mathilde; Tatard, Caroline; Chaval, Yannick; Suputtamongkol, Yupin; Buchy, Philippe; Jittapalapong, Sathaporn; Herbreteau, Vincent; Morand, Serge

      2014-01-01

      Background Leptospirosis is the most common bacterial zoonoses and has been identified as an important emerging global public health problem in Southeast Asia. Rodents are important reservoirs for human leptospirosis, but epidemiological data is lacking. Methodology/Principal Findings We sampled rodents living in different habitats from seven localities distributed across Southeast Asia (Thailand, Lao PDR and Cambodia), between 2009 to 2010. Human isolates were also obtained from localities close to where rodents were sampled. The prevalence of Leptospira infection was assessed by real-time PCR using DNA extracted from rodent kidneys, targeting the lipL32 gene. Sequencing rrs and secY genes, and Multi Locus Variable-number Tandem Repeat (VNTR) analyses were performed on DNA extracted from rat kidneys for Leptospira isolates molecular typing. Four species were detected in rodents, L. borgpetersenii (56% of positive samples), L. interrogans (36%), L. kirschneri (3%) and L. weilli (2%), which were identical to human isolates. Mean prevalence in rodents was approximately 7%, and largely varied across localities and habitats, but not between rodent species. The two most abundant Leptospira species displayed different habitat requirements: L. interrogans was linked to humid habitats (rice fields and forests) while L. borgpetersenii was abundant in both humid and dry habitats (non-floodable lands). Conclusion/Significance L. interrogans and L. borgpetersenii species are widely distributed amongst rodent populations, and strain typing confirmed rodents as reservoirs for human leptospirosis. Differences in habitat requirements for L. interrogans and L. borgpetersenii supported differential transmission modes. In Southeast Asia, human infection risk is not only restricted to activities taking place in wetlands and rice fields as is commonly accepted, but should also include tasks such as forestry work, as well as the hunting and preparation of rodents for consumption, which

    15. Testing the limits of Rodent Sperm Analysis: azoospermia in an otherwise healthy wild rodent population.

      Science.gov (United States)

      Tannenbaum, Lawrence V; Thran, Brandolyn H; Willams, Keith J

      2009-01-01

      By comparing the sperm parameters of small rodents trapped at contaminated terrestrial sites and nearby habitat-matched noncontaminated locations, the patent-pending Rodent Sperm Analysis (RSA) method provides a direct health status appraisal for the maximally chemical-exposed mammalian ecological receptor in the wild. RSA outcomes have consistently allowed for as definitive determinations of receptor health as are possible at the present time, thereby streamlining the ecological risk assessment (ERA) process. Here, we describe the unanticipated discovery, at a contaminated US EPA Superfund National Priorities List site, of a population of Hispid cotton rats (Sigmodon hispidus), with a high percentage of adult males lacking sperm entirely (azoospermia). In light of the RSA method's role in streamlining ERAs and in bringing contaminated Superfund-type site investigations to closure, we consider the consequences of the discovery. The two matters specifically discussed are (1) the computation of a population's average sperm count where azoospermia is present and (2) the merits of the RSA method and its sperm parameter thresholds-for-effect when azoospermia is masked in an otherwise apparently healthy rodent population.

    16. Influência do grupo de pares e uso de drogas ilícitas entre adolescentes brasileiros: um estudo transversal

      Directory of Open Access Journals (Sweden)

      Kelly Oliva Jorge

      2018-03-01

      Full Text Available O estudo teve como objetivo examinar o uso de drogas ilícitas e as associações com fatores socioeconômicos e influência do grupo de pares entre adolescentes brasileiros de 15 a 19 anos de idade. Foi adotada uma amostra de clusters em dois estágios, com a seleção aleatória de escolas públicas e privadas entre os nove distritos administrativos de uma capital de estado, e a seleção aleatória de turmas em cada escola. A variável de desfecho foi o uso de drogas ilícitas, medido pela seguinte pergunta: “Você já usou drogas ilícitas (maconha, inalantes, hipnóticos, cocaína/crack, alucinógenos, anfetaminas e/ou opióides alguma vez na vida?”. Os grupos de pares foram classificados como: escola, família, atividades religiosas e esportes/cultura. O nível socioeconômico foi avaliado com o Índice de Vulnerabilidade em Saúde (IVS baseado em área. Foram analisados os dados de 91 adolescentes com o teste do qui-quadrado e regressão logística. A proporção global de uso de drogas ilícitas foi 15,2%. A heterogeneidade por gênero dentro de grupos (OR = 3,14; IC95%: 1,63-6,06, amizades baseadas em religião (OR = 0,36; IC95%: 0,17-0,75 e amizades baseadas em esportes/cultura (OR = 0,44; IC95%: 0,22-0,87 permaneceram associadas significativamente com o uso de drogas ilícitas. Os adolescentes que residiam em áreas menos vulneráveis mostraram maior probabilidade de uso de drogas ilícitas, quando comparados aos jovens em áreas mais vulneráveis. As amizades baseadas em religião e esportes/cultura parecem ter um efeito protetor contra o uso de drogas ilícitas. A heterogeneidade de gênero dentro de grupos e a residência em áreas menos vulneráveis aumentaram as chances de uso de drogas ilícitas por adolescentes.

    17. RODENT AND HUMAN NEUROPROGENITOR CELLS FOR HIGH-CONTENT SCREENS OF CHEMICAL EFFECTS ON PROLIFERATION AND APOPTOSIS

      Science.gov (United States)

      The objective of these experiments is to develop high-throughput screens for proliferation and apoptosis in order to compare rodent and human neuroprogenitor cell responses to potential developmental neurotoxicants. Effects of 4 chemicals on proliferation and apoptosis in mouse c...

    18. Rodent Habitat on ISS: Advances in Capability for Determining Spaceflight Effects on Mammalian Physiology

      Science.gov (United States)

      Globus, R. K.; Choi, S.; Gong, C.; Leveson-Gower, D.; Ronca, A.; Taylor, E.; Beegle, J.

      2016-01-01

      Rodent research is a valuable essential tool for advancing biomedical discoveries in life sciences on Earth and in space. The National Research Counsel's Decadal survey (1) emphasized the importance of expanding NASAs life sciences research to perform long duration, rodent experiments on the International Space Station (ISS). To accomplish this objective, new flight hardware, operations, and science capabilities were developed at NASA ARC to support commercial and government-sponsored research. The flight phases of two separate spaceflight missions (Rodent Research-1 and Rodent Research-2) have been completed and new capabilities are in development. The first flight experiments carrying 20 mice were launched on Sept 21, 2014 in an unmanned Dragon Capsule, SpaceX4; Rodent Research-1 was dedicated to achieving both NASA validation and CASIS science objectives, while Rodent Reesearch-2 extended the period on orbit to 60 days. Groundbased control groups (housed in flight hardware or standard cages) were maintained in environmental chambers at Kennedy Space Center. Crewmembers previously trained in animal handling transferred mice from the Transporter into Habitats under simultaneous veterinary supervision by video streaming and were deemed healthy. Health and behavior of all mice on the ISS was monitored by video feed on a daily basis, and post-flight quantitative analyses of behavior were performed. The 10 mice from RR-1 Validation (16wk old, female C57Bl6/J) ambulated freely and actively throughout the Habitat, relying heavily on their forelimbs for locomotion. The first on-orbit dissections of mice were performed successfully, and high quality RNA (RIN values>9) and liver enzyme activities were obtained, validating the quality of sample recovery. Post-flight sample analysis revealed that body weights of FLT animals did not differ from ground controls (GC) housed in the same hardware, or vivarium controls (VIV) housed in standard cages. Organ weights analyzed post

    19. Fruit Size Determines the Role of Three Scatter-Hoarding Rodents as Dispersers or Seed Predators of a Fleshy-Fruited Atacama Desert Shrub

      Science.gov (United States)

      Loayza, Andrea P.; Squeo, Francisco A.

      2016-01-01

      Scatter-hoarding rodents can act as both predators and dispersers for many large-seeded plants because they cache seeds for future use, but occasionally forget them in sites with high survival and establishment probabilities. The most important fruit or seed trait influencing rodent foraging behavior is seed size; rodents prefer large seeds because they have higher nutritional content, but this preference can be counterbalanced by the higher costs of handling larger seeds. We designed a cafeteria experiment to assess whether fruit and seed size of Myrcianthes coquimbensis, an endangered desert shrub, influence the decision-making process during foraging by three species of scatter-hoarding rodents differing in body size: Abrothrix olivaceus, Phyllotis darwini and Octodon degus. We found that the size of fruits and seeds influenced foraging behavior in the three rodent species; the probability of a fruit being harvested and hoarded was higher for larger fruits than for smaller ones. Patterns of fruit size preference were not affected by rodent size; all species were able to hoard fruits within the entire range of sizes offered. Finally, fruit and seed size had no effect on the probability of seed predation, rodents typically ate only the fleshy pulp of the fruits offered and discarded whole, intact seeds. In conclusion, our results reveal that larger M. coquimbensis fruits have higher probabilities of being harvested, and ultimately of its seeds being hoarded and dispersed by scatter-hoarding rodents. As this plant has no other dispersers, rodents play an important role in its recruitment dynamics. PMID:27861550

    20. A Community-Based Surveillance on Determinants of Rodent Infestation

      Directory of Open Access Journals (Sweden)

      Hsiu-Hua Pai

      2003-01-01

      Full Text Available Rodent infestation is an important factor in the transmission of infectious diseases of public health importance. From October to November 1998, surveillance stations were established in 110 boroughs of Kaohsiung City in southern Taiwan. Boroughs were chosen by random sampling 10 boroughs from each of 11 districts (464 boroughs in the city. The extent of rodent infestation was determined by cage trapping. The possibility of applying a community-based control program was evaluated by investigating associated demographic and environmental factors as well as related knowledge, attitudes, and behaviors. A total of 90 rodents were trapped in 41% of the 110 boroughs. Using univariate analyses, 17 factors were significantly associated with rodent infestation. A lack of knowledge that rodent control relies on community cooperation was the most important factor among the seven variables associated with the extent of rodent infestation (OR 3.1 by logistic multiple regression. This revealed the importance of community cooperation in controlling rodent infestation. Moreover, improvement of environmental hygiene associated with garbage problems, such as cleanliness of storage rooms and closets, and the hygiene of empty space and resource recycling stations should not be ignored.

    1. Adolescência e aids: avaliação de uma experiência de educação preventiva entre pares

      Directory of Open Access Journals (Sweden)

      José Ricardo de Carvalho Mesquita Ayres

      2003-02-01

      Full Text Available Ações preventivas de HIV/AIDS, orientadas à superação dos limites das intervenções de corte comportamentalista, incorporando preocupações com os determinantes sócio-culturais desses comportamentos, constituem hoje uma necessidade e, ao mesmo tempo, uma lacuna. O presente artigo trata de estudo de prevenção no ambiente escolar baseado em estratégia de redução de vulnerabilidade. Constitui um estudo de caso, de corte quanti-quali, que, no contexto desta estratégia, avalia o trabalho de prevenção de aids desenvolvido por alunos multiplicadores em uma escola estadual de ensino médio na periferia da cidade de São Paulo. Entre os resultados, destacam-se: a efetividade da proposta, com ampla aceitação e favorável aproveitamento pelos alunos da escola; o perfil diversificado do aluno multiplicador voluntário; e a tensão entre modelos cognitivo-comportamentalistas e social-construtivistas nos processos educativos concretamente operados pelos multiplicadores. Conclui-se pela possibilidade e interesse da ação de alunos multiplicadores na perspectiva das estratégias de redução de vulnerabilidade, apontando-se a necessidade de desenvolver mecanismos de captação e capacitação capazes de problematizar e superar a tensão apontada.

    2. Caffeine enhancement of x-ray killing in cultured human and rodent cells

      International Nuclear Information System (INIS)

      Waldren, C.A.; Rasko, I.

      1978-01-01

      A 16 to 20 hr postirradiation incubation with caffeine enhances x-ray killing of rodent and human cells. Cells tested were Chinese hamster ovary (CHO-K1), lung (CHL), V79, mouse L, HeLa S3, human fibroblasts (AF288, TC171, FS9, CRL1166), and a human-hamster hybrid. The effect of caffeine on the x-ray survival curve of these cells was to remove the initial shoulder without significantly altering the mean lethal dose (D 0 ). This action can be achieved at caffeine concentrations which of themselves cause less than 15% killing. In randomly growing CHO-K1 cells the caffeine-sensitive process occurs with a half-time of 2 to 5 hr after irradiation. These experiments indicate the existence in human and rodent cells of caffeine-inhibited genome repair for x-ray damage

    3. Estallido traumático de prótesis mamaria con migración masiva de silicona a pared abdominal

      Directory of Open Access Journals (Sweden)

      E. Guisantes

      Full Text Available Presentamos el caso de una mujer de 39 años portadora de implantes mamarios de gel cohesivo de silicona, en plano subglandular, vía submamaria, por mamoplastia de aumento estético practicada 13 años antes. Acude a la consulta tras haber sufrido un traumatismo costal por precipitación accidental desde un puente de 3 metros de altura, presentando dolor, distorsión en la forma de la mama izquierda y endurecimiento con tumefacción de hemipared abdominal izquierda. La exploración radiológica mostró estallido extracapsular de la prótesis mamaria izquierda con migración de la silicona hacia el espacio subcutáneo abdominal, llegando a cresta ilíaca. Retiramos ambas prótesis con sus cápsulas y extirpamos toda la silicona migrada junto con la neocápsula fibrosa formada alrededor de la silicona en la pared abdominal, mediante una cuidadosa disección desde las incisiones submamarias previas.

    4. Tutorías académicas: desafíos de un programa piloto entre pares en una universidad no selectiva

      Directory of Open Access Journals (Sweden)

      Paola Andreucci-Annunziata

      2017-01-01

      Full Text Available Se presentan los desafíos y las posibilidades de un programa piloto de tutorías entre pares en el contexto de una institución universitaria de acceso abierto y de carácter no selectivo. Se plantean los fundamentos del programa, las fases de reclutamiento y selección de tutores, el proceso de formación de los tutores, el programa de tutorías diferenciado por comunidades de apoyo ‒lectoescritura, razonamiento lógico y matemática‒, su implementación y los resultados de efectividad obtenidos en los tutorados. Para ello, se consideran las demandas de apoyo académico de los estudiantes y los porcentajes de aprobación luego de implementado el programa en las actividades curriculares del semestre lectivo cursado. Se discuten los resultados del plan piloto y se plantean ciertos desafíos referentes a la cobertura del programa, las estrategias utilizadas para la captación de la motivación y la persistencia del estudiante en la instancia de acompañamiento y la focalización en las «inter‒comunidades» como cristalización paradigmática de la perspectiva transversal, competencial, incremental y dialógica de la propuesta presentada.

    5. Leptospira and rodents in Cambodia : environmental determinants of infection

      OpenAIRE

      Ivanova, S.; Herbreteau, Vincent; Blasdell, K.; Chaval, Y.; Buchy, P.; Guillard, B.; Morand, S.

      2012-01-01

      We investigated infection of rodents and shrews by Leptospira spp. in two localities of Cambodia (Veal Renh, Kaev Seima) and in four types of habitat (forests, non-flooded lands, lowland rain-fed paddy fields, houses) during the wet and the dry seasons. Habitat preference was common, and rodent and shrew species were found only in houses or in rain-fed paddy fields or in forests. Among 649 small mammals trapped belonging to 12 rodent species and 1 shrew species, 71 of 642 animals tested were ...

    6. The bioeconomics of controlling an African rodent pest species

      DEFF Research Database (Denmark)

      Skonhoft, Anders; Leirs, Herwig; Andreassen, Harry P

      2006-01-01

      The paper treats the economy of controlling an African pest rodent, the multimammate rat, causing major damage in maize production. An ecological population model is presented and used as a basis for the economic analyses carried out at the village level using data from Tanzania. This model...... incorporates both density-dependent and density-independent (stochastic) factors. Rodents are controlled by applying poison, and the costs are made up of the cost of poison plus the damage to maize production. We analyse how the present-value costs of maize production are affected by various rodent control...

    7. Normas percibidas por los estudiantes universitarios acerca de sus pares y uso de drogas en una universidad en Chile Normas percebidas pelos estudantes universitários sobre seus pares e uso de drogas de uma universidade Chilena Perceived norms among university students about their peers and drug use at a Chilean university

      Directory of Open Access Journals (Sweden)

      Julia Ramirez Castillo

      2009-01-01

      Full Text Available En este estudio se analiza la relación entre las normas percibidas del consumo de drogas en los pares y el uso actual de la misma, en estudiantes universitarios. Se trata de un estudio cuantitativo, multicéntrico aplicado a la población del 2 y 3 año de carreras de salud de una universidad chilena, la muestra fue constituida por 286(75,2% estudiantes de un total de 380. Se observó que más del 50%, perciben que sus pares consumen tabaco diariamente, alcohol tres veces a la semana, marihuana una vez a la semana, y cocaína al menos una vez al año. El campus es el lugar donde más se consume; sin embargo la cocaína se consume más en casa de amigos. Entre los estudiantes, el 68% fumó alguna una vez en la vida y el 57% todos los días; el 88% bebió alguna una vez en la vida; el 26% consumió marihuana alguna una vez en la vida y el 16% en los últimos 12 meses. Los estudiantes desconocen la existencia de políticas universitarias relacionadas con el consumo de drogas. Algunos resultados confirman la sobrestimación del consumo de drogas.Analisa-se a relação entre normas percebidas do consumo de drogas pelos pares e o uso da mesma entre estudantes universitários. Este é um estudo quantitativo, multicêntrico, aplicado aos alunos do 2 e 3 ano dos cursos da área da saúde de uma universidade chilena, constituída por 286 (75,2% de 380 estudantes. RESULTADOS: mais de 50%, percebem que seus pares consomem cigarro diariamente, álcool três vezes por semana, maconha uma vez por semana; cocaína ao menos uma vez no ano. O campus é o local onde mais se consome; o consumo de cocaína se dá na casa de amigos. Entre os estudantes, 68% já fumou uma vez em sua vida, 57% todos os dias; 88% já bebeu uma vez em sua vida; 26% consumiu maconha uma vez na vida, 16% nos últimos 12 meses. Estudantes desconhecem a existência de políticas universitárias relacionadas ao consumo de drogas. Alguns resultados confirmam a subestimação do consumo de

    8. Rodent models of adaptive decision making.

      Science.gov (United States)

      Izquierdo, Alicia; Belcher, Annabelle M

      2012-01-01

      Adaptive decision making affords the animal the ability to respond quickly to changes in a dynamic environment: one in which attentional demands, cost or effort to procure the reward, and reward contingencies change frequently. The more flexible the organism is in adapting choice behavior, the more command and success the organism has in navigating its environment. Maladaptive decision making is at the heart of much neuropsychiatric disease, including addiction. Thus, a better understanding of the mechanisms that underlie normal, adaptive decision making helps achieve a better understanding of certain diseases that incorporate maladaptive decision making as a core feature. This chapter presents three general domains of methods that the experimenter can manipulate in animal decision-making tasks: attention, effort, and reward contingency. Here, we present detailed methods of rodent tasks frequently employed within these domains: the Attentional Set-Shift Task, Effortful T-maze Task, and Visual Discrimination Reversal Learning. These tasks all recruit regions within the frontal cortex and the striatum, and performance is heavily modulated by the neurotransmitter dopamine, making these assays highly valid measures in the study of psychostimulant addiction.

    9. Navigating actions through the rodent parietal cortex

      Directory of Open Access Journals (Sweden)

      Jonathan R. Whitlock

      2014-05-01

      Full Text Available The posterior parietal cortex (PPC participates in a manifold of cognitive functions, including visual attention, working memory, spatial processing and movement planning. Given the vast interconnectivity of PPC with sensory and motor areas, it is not surprising that neuronal recordings show that PPC often encodes mixtures of spatial information as well as the movements required to reach a goal. Recent work sought to discern the relative strength of spatial versus motor signaling in PPC by recording single unit activity in PPC of freely behaving rats during selective changes in either the spatial layout of the local environment or in the pattern of locomotor behaviors executed during navigational tasks. The results revealed unequivocally a predominant sensitivity of PPC neurons to locomotor action structure, with subsets of cells even encoding upcoming movements more than 1 second in advance. In light of these and other recent findings in the field, I propose that one of the key contributions of PPC to navigation is the synthesis of goal-directed behavioral sequences, and that the rodent PPC may serve as an apt system to investigate cellular mechanisms for spatial motor planning as traditionally studied in humans and monkeys.

    10. Bone morphology of the hind limbs in two caviomorph rodents.

      Science.gov (United States)

      de Araújo, F A P; Sesoko, N F; Rahal, S C; Teixeira, C R; Müller, T R; Machado, M R F

      2013-04-01

      In order to evaluate the hind limbs of caviomorph rodents a descriptive analysis of the Cuniculus paca (Linnaeus, 1766) and Hydrochoerus hydrochaeris (Linnaeus, 1766) was performed using anatomical specimens, radiography, computed tomography (CT) and full-coloured prototype models to generate bone anatomy data. The appendicular skeleton of the two largest rodents of Neotropical America was compared with the previously reported anatomical features of Rattus norvegicus (Berkenhout, 1769) and domestic Cavia porcellus (Linnaeus, 1758). The structures were analyzed macroscopically and particular findings of each species reported. Features including the presence of articular fibular projection and lunulae were observed in the stifle joint of all rodents. Imaging aided in anatomical description and, specifically in the identification of bone structures in Cuniculus paca and Hydrochoerus hydrochaeris. The imaging findings were correlated with the anatomical structures observed. The data may be used in future studies comparing these animals to other rodents and mammalian species. © 2012 Blackwell Verlag GmbH.

    11. First Isolates of Leptospira spp., from Rodents Captured in Angola

      Science.gov (United States)

      Fortes-Gabriel, Elsa; Carreira, Teresa; Vieira, Maria Luísa

      2016-01-01

      Rodents play an important role in the transmission of pathogenic Leptospira spp. However, in Angola, neither the natural reservoirs of these spirochetes nor leptospirosis diagnosis has been considered. Regarding this gap, we captured rodents in Luanda and Huambo provinces to identify circulating Leptospira spp. Rodent kidney tissue was cultured and DNA amplified and sequenced. Culture isolates were evaluated for pathogenic status and typing with rabbit antisera; polymerase chain reaction (PCR) and sequencing were also performed. A total of 37 rodents were captured: Rattus rattus (15, 40.5%), Rattus norvegicus (9, 24.3%), and Mus musculus (13, 35.2%). Leptospiral DNA was amplified in eight (21.6%) kidney samples. From the cultures, we obtained four (10.8%) Leptospira isolates belonging to the Icterohaemorrhagiae and Ballum serogroups of Leptospira interrogans and Leptospira borgpetersenii genospecies, respectively. This study provides information about circulating leptospires spread by rats and mice in Angola. PMID:26928840

    12. Prevalence of leptospirosis and toxoplasmosis: A study of rodents ...

      African Journals Online (AJOL)

      prevalence of toxoplasmosis in child-bearing women in rural Sudan is even higher ranging ... crops. Animal trapping. Live rodents and shrews were captured in cultivated ..... P., Hodný, Z. & Vondrová, M. (2011) Fatal attraction phenomenon in.

    13. First Isolates of Leptospira spp., from Rodents Captured in Angola.

      Science.gov (United States)

      Fortes-Gabriel, Elsa; Carreira, Teresa; Vieira, Maria Luísa

      2016-05-04

      Rodents play an important role in the transmission of pathogenic Leptospira spp. However, in Angola, neither the natural reservoirs of these spirochetes nor leptospirosis diagnosis has been considered. Regarding this gap, we captured rodents in Luanda and Huambo provinces to identify circulating Leptospira spp. Rodent kidney tissue was cultured and DNA amplified and sequenced. Culture isolates were evaluated for pathogenic status and typing with rabbit antisera; polymerase chain reaction (PCR) and sequencing were also performed. A total of 37 rodents were captured: Rattus rattus (15, 40.5%), Rattus norvegicus (9, 24.3%), and Mus musculus (13, 35.2%). Leptospiral DNA was amplified in eight (21.6%) kidney samples. From the cultures, we obtained four (10.8%) Leptospira isolates belonging to the Icterohaemorrhagiae and Ballum serogroups of Leptospira interrogans and Leptospira borgpetersenii genospecies, respectively. This study provides information about circulating leptospires spread by rats and mice in Angola. © The American Society of Tropical Medicine and Hygiene.

    14. New Development in NASA's Rodent Research Hardware for Conducting Long Duration Biomedical and Basic Research in Space

      Science.gov (United States)

      Shirazi-Fard, Y.; Choi, S.; Harris, C.; Gong, C.; Beegle, J. E.; Stube, K. C.; Martin, K. J.; Nevitt, R. G.; Globus, R. G.

      2017-01-01

      Animal models, particularly rodents, are the foundation of pre-clinical research to understand human diseases and evaluate new therapeutics, and play a key role in advancing biomedical discoveries both on Earth and in space. The National Research Councils Decadal survey emphasized the importance of expanding NASAs life sciences research to perform long duration, rodent experiments on the International Space Station (ISS). To accomplish this objective, flight hardware, operations, and science capabilities were developed at NASA Ames Research Center (ARC) to enhance science return for both commercial (CASIS) and government-sponsored rodent research. The Rodent Research program at NASA ARC has pioneered a new research capability on the International Space Station and has progressed toward translating research to the ISS utilizing commercial rockets, collaborating with academia and science industry, while training crewmembers to assist in performing research on orbit. Throughout phases of these missions, our practices, hardware and operations have evolved from tested to developed standards, and we are able to modify and customize our procedure and operations for mission specific requirements. The Rodent Research Habitat is capable of providing a living environment for animals on ISS according to standard animal welfare requirements. Using the cameras in the Habitat, the Rodent Research team has the ability to perform daily health checks on animals, and further analyze the collected videos for behavioral studies. A recent development of the Rodent Research hardware is inclusion of enrichment, to provide the animals the ability to rest and huddle. The Enrichment Hut is designed carefully for adult mice (up to 35 week old) within animal welfare, engineering, and operations constraints. The Hut is made out of the same stainless steel mesh as the cage interior, it has an ingress and an egress to allow animals move freely, and a hinge door to allow crewmembers remove the

    15. Parasitocenoses in productional rodent breeds in Czech Republic

      Directory of Open Access Journals (Sweden)

      Marie Borkovcová

      2009-01-01

      Full Text Available Aim of this work was to monitor the occurrence of most common parasites of rodents in 13 commercial and hobby breeds. Most often detected protozoans belonged to genera Giardia, Eimeria and Cryptosporidium, tapeworms Hymenolepis nana and H. diminuta, nematods Syphacia obvelata and Aspiculuris tetraptera and mites Ornithonyssus bacoti, Laelaps hilaris and Notoedres muris. Diseases broke out mainly during summer months. In animals with clinical signs of illnesses there was an expectation of pa­ra­si­te presence, and most of them were nematods – 80%, tapeworms – 45.2%, protozoans – 41.1% and ectoparasites – 22%. Samples of animals without clinical signs of illnesses contained nematods – 16%, tapeworms – 11%, coccidians – 6% and ectoparasites – 0%. Besides evaluation of all samples, breeding conditions were evaluated as well. Consequently plan was made to remove the causes of parasitoses for each monitored breed. Most dangerous parasites were coccidians of the genus Cryp­tos­po­ri­dium, which caused high mortality of the young animals. In Czech Republic high percent of breeds are contaminated with parasites, however, there is little experience in how to deal with these illnesses. Results are weak and low-quality breeds, especially of mice and common rats. Important protection is buying animals from well-known and verified breed with no signs of illness and also regular control of excrement samples.

    16. Nicotine Vapor Method to Induce Nicotine Dependence in Rodents.

      Science.gov (United States)

      Kallupi, Marsida; George, Olivier

      2017-07-05

      Nicotine, the main addictive component of tobacco, induces potentiation of brain stimulation reward, increases locomotor activity, and induces conditioned place preference. Nicotine cessation produces a withdrawal syndrome that can be relieved by nicotine replacement therapy. In the last decade, the market for electronic cigarettes has flourished, especially among adolescents. The nicotine vaporizer or electronic nicotine delivery system is a battery-operated device that allows the user to simulate the experience of tobacco smoking without inhaling smoke. The device is designed to be an alternative to conventional cigarettes that emits vaporized nicotine inhaled by the user. This report describes a procedure to vaporize nicotine in the air to produce blood nicotine levels in rodents that are clinically relevant to those that are observed in humans and produce dependence. We also describe how to construct the apparatus to deliver nicotine vapor in a stable, reliable, and consistent manner, as well as how to analyze air for nicotine content. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

    17. Validating excised rodent lungs for functional hyperpolarized xenon-129 MRI.

      Directory of Open Access Journals (Sweden)

      David M L Lilburn

      Full Text Available Ex vivo rodent lung models are explored for physiological measurements of respiratory function with hyperpolarized (hp (129Xe MRI. It is shown that excised lung models allow for simplification of the technical challenges involved and provide valuable physiological insights that are not feasible using in vivo MRI protocols. A custom designed breathing apparatus enables MR images of gas distribution on increasing ventilation volumes of actively inhaled hp (129Xe. Straightforward hp (129Xe MRI protocols provide residual lung volume (RV data and permit for spatially resolved tracking of small hp (129Xe probe volumes during the inhalation cycle. Hp (129Xe MRI of lung function in the excised organ demonstrates the persistence of post mortem airway responsiveness to intravenous methacholine challenges. The presented methodology enables physiology of lung function in health and disease without additional regulatory approval requirements and reduces the technical and logistical challenges with hp gas MRI experiments. The post mortem lung functional data can augment histological measurements and should be of interest for drug development studies.

    18. Traumatic brain injury–Modeling neuropsychiatric symptoms in rodents

      Directory of Open Access Journals (Sweden)

      Oz eMalkesman

      2013-10-01

      Full Text Available Each year in the United States, approximately 1.5 million people sustain a traumatic brain injury (TBI. Victims of TBI can suffer from chronic post-TBI symptoms, such as sensory and motor deficits, cognitive impairments including problems with memory, learning, and attention, and neuropsychiatric symptoms such as depression, anxiety, irritability, aggression, and suicidal rumination. Although partially associated with the site and severity of injury, the biological mechanisms associated with many of these symptoms—and why some patients experience differing assortments of persistent maladies—are largely unknown. The use of animal models is a promising strategy for elucidation of the mechanisms of impairment and treatment, and learning, memory, sensory and motor tests have widespread utility in rodent models of TBI and psychopharmacology. Comparatively, behavioral tests for the evaluation of neuropsychiatric symptomatology are rarely employed in animal models of TBI and, as determined in this review, the results have been inconsistent. Animal behavioral studies contribute to the understanding of the biological mechanisms by which TBI is associated with neurobehavioral symptoms and offer a powerful means for pre-clinical treatment validation. Therefore, further exploration of the utility of animal behavioral tests for the study of injury mechanisms and therapeutic strategies for the alleviation of emotional symptoms are relevant and essential.

    19. The bioeconomics of controlling an African rodent pest species

      OpenAIRE

      Skonhoft, Anders; Herwig, Leirs; Andreassen, Harry Peter; Mulungu, Loth S. A.; Stenseth, Nils Christian

      2006-01-01

      The paper treats the economy of controlling an African pest rodent, the multimammate rat, causing major damage in maize production. An ecological population model is presented and used as a basis for the economic analyses carried out at the village level using data from Tanzania. This model incorporates both density-dependent and density-independent (stochastic) factors. Rodents are controlled by applying poison, and the economic benefits depend on the income from maize production minus the c...

    20. Ectoparasites of Rodents Captured in Hamedan, Western Iran

      Directory of Open Access Journals (Sweden)

      Hamid Zendehfili

      2015-10-01

      Full Text Available Background: Rodents with a population greater than the entire population of other mammals on earth are the source of economic losses and health conflicts. One of the major health problems with the rodents is their role as reservoir hosts of zoonotic diseases. The aim of this study was to assess the infestation of commensal rodents with ectoparasites in Hamedan City, Western Iran.Methods: The samples were collected by live traps during years 2012–2013. After transferring the samples to the Entomological Laboratory of Hamedan University of Medical Sciences, their ectoparasites were collected andidentified.Results: A total of 171 slides were prepared from 105 captured commensal rodents: Mus musculus, Rattus rattus and R. norvegicus comprising three orders namely Mesostigmata: Hypoaspis (Laelaspis astronomica, Dermanyssius sp, Pachylaelapidae (male. Metastigmata: Rhipicephalus sp and Anoplura: Polyplax spinulosa were recovered in Hamedan City. Seventy (66.6% rodents were found infested with at least one species of ectoparasites.Conclusion: The results of our study indicate that ectoparasites infestation in commensal rodents of Hamedan city is high and more attention by local health authorities is needed to prevent zoonotic diseases.

    1. Template based rodent brain extraction and atlas mapping.

      Science.gov (United States)

      Weimin Huang; Jiaqi Zhang; Zhiping Lin; Su Huang; Yuping Duan; Zhongkang Lu

      2016-08-01

      Accurate rodent brain extraction is the basic step for many translational studies using MR imaging. This paper presents a template based approach with multi-expert refinement to automatic rodent brain extraction. We first build the brain appearance model based on the learning exemplars. Together with the template matching, we encode the rodent brain position into the search space to reliably locate the rodent brain and estimate the rough segmentation. With the initial mask, a level-set segmentation and a mask-based template learning are implemented further to the brain region. The multi-expert fusion is used to generate a new mask. We finally combine the region growing based on the histogram distribution learning to delineate the final brain mask. A high-resolution rodent atlas is used to illustrate that the segmented low resolution anatomic image can be well mapped to the atlas. Tested on a public data set, all brains are located reliably and we achieve the mean Jaccard similarity score at 94.99% for brain segmentation, which is a statistically significant improvement compared to two other rodent brain extraction methods.

    2. Endocarp thickness affects seed removal speed by small rodents in a warm-temperate broad-leafed deciduous forest, China

      Science.gov (United States)

      Zhang, Hongmao; Zhang, Zhibin

      2008-11-01

      Seed traits are important factors affecting seed predation by rodents and thereby the success of recruitment. Seeds of many tree species have hard hulls. These are thought to confer mechanical protection, but the effect of endocarp thickness on seed predation by rodents has not been well investigated. Wild apricot ( Prunus armeniaca), wild peach ( Amygdalus davidiana), cultivated walnut ( Juglans regia), wild walnut ( Juglans mandshurica Maxim) and Liaodong oak ( Quercus liaotungensis) are very common tree species in northwestern Beijing city, China. Their seeds vary greatly in size, endocarp thickness, caloric value and tannin content. This paper aims to study the effects of seed traits on seed removal speed of these five tree species by small rodents in a temperate deciduous forest, with emphasis on the effect of endocarp thickness. The results indicated that speed of removal of seeds released at stations in the field decreased significantly with increasing endocarp thickness. We found no significant correlations between seed removal speed and other seed traits such as seed size, caloric value and tannin content. In seed selection experiments in small cages, Père David's rock squirrel ( Sciurotamias davidianus), a large-bodied, strong-jawed rodent, selected all of the five seed species, and the selection order among the five seed species was determined by endocarp thickness and the ratio of endocarp mass/seed mass. In contrast, the Korean field mouse ( Apodemus peninsulae) and Chinese white-bellied rat ( Niviventer confucianus), with relatively small bodies and weak jaws, preferred to select small seeds like acorns of Q. liaotungensis and seeds of P. armeniaca, indicating that rodent body size is also an important factor affecting food selection based on seed size. These results suggest endocarp thickness significantly reduces seed removal speed by rodents and then negatively affects dispersal fitness of seeds before seed removal of tree species in the study

    3. Post-dispersal seed removal by ground-feeding rodents in tropical peatlands, Central Kalimantan, Indonesia

      Science.gov (United States)

      Blackham, Grace V.; Corlett, Richard T.

      2015-01-01

      Forested tropical peatlands in Southeast Asia are being rapidly converted to agriculture or degraded into non-forest vegetation. Although large areas have been abandoned, there is little evidence for subsequent forest recovery. As part of a study of forest degradation and recovery, we used seed removal experiments and rodent surveys to investigate the potential role of post-dispersal seed predation in limiting the regeneration of woody plants. Two 14-day seed removal trials were done in deforested and forested peatland habitat in Central Kalimantan, Indonesia. Seeds of Nephelium lappaceum, Syzygium muelleri, Artocarpus heterophyllus (all animal-dispersed) and Combretocarpus rotundatus (wind-dispersed) were tested. Significantly more seeds (82.8%) were removed in forest than non-forest (38.1%) and Combretocarpus had the lowest removal in both habitats. Most handled seeds were eaten in situ and little caching was observed. Six species of rodents were captured in forest and five in non-forest. The most trapped taxa were three Maxomys spp. in forest (85.5% of individuals) and Rattus tiomanicus in non-forest (74.8%). Camera traps confirmed that rodents were responsible for seed removal. Seed predation in deforested areas, which have a much lower seed rain than forest, may contribute to the low density and diversity of regenerating forest. PMID:26369444

    4. Hematological profile as a crude oil exposure-related marker in wild rodents

      Directory of Open Access Journals (Sweden)

      Ana L. Muccillo-Baisch

      2013-01-01

      Full Text Available The toxicity of petroleum components is well described in the literature, especially with regard to mutagenic and carcinogenic effects. In some groups of animals, such as birds, oil exposure seems to alter blood parameters, while this relationship is poorly understood in rodents. The study aimed to investigate alterations in hematological profile in the wild rodent Calomys laucha exposed to crude oil contaminated soils. In this study, males specimens of Calomys laucha were exposed for 14 days to two soils contaminated by petroleum: (I landfarming soil, coming from a bioremediation area of contaminated soil from a Petrochemical Complex through landfarming technique and (II soil of a simulated oil spill in laboratory conditions. The animals were exposed individually in cages containing 1 kg soil with free access to food and water. Control animals were exposed to an artificial uncontaminated soil. At the end of the experiment, animals were anesthetized and blood was collected for hematological profile. The animals exposed to soil landfarming had significant reduction in the number of bands, segmented, eosinophils, monocytes, lymphocytes and increased red cell distribution width (RDW, while animals exposed to simulated soil spillage in laboratory had decreased number of bands, but an increase in the number of lymphocytes and platelets. These changes in hemostasis may indicate an early stage of the development of associated pathologies, while the hematological profile can be used as a crude oil exposure-related marker in wild rodents.

    5. Tratamiento de los defectos congénitos de la pared abdominal (gastrosquisis y onfalocele en el Hospital Universitario San Vicente de Paúl, 1998-2006

      Directory of Open Access Journals (Sweden)

      Paula Jaramillo Gómez

      2008-11-01

      Full Text Available INTRODUCCIÓN: la gastrosquisis y el onfalocele son malformaciones neonatales de la pared abdominal que, a pesar de sus grandes diferencias, comparten el manifestarse por herniación de las vísceras intraabdominales a través de un defecto de la pared abdominal. Los niños con estas enfermedades se presentan como emergencias quirúrgicas que plantean un reto al cirujano tratante. Tienen una tasa de mortalidad que oscila entre 40 y 60% aun con el tratamiento apropiado y se asocian a un amplio rango de malformaciones, principalmente en los que tienen diagnóstico de onfalocele. El objetivo de la presente revisión retrospectiva fue describir el tratamiento y los resultados obtenidos en estos pacientes, entre 1998 y 2006, en el Servicio de Cirugía infantil del Hospital Universitario San Vicente de Paúl, de Medellín, Colombia. PACIENTES Y MÉTODOS: se evaluaron todos los pacientes que ingresaron al Servicio de Cirugía infantil del HUSVP con diagnóstico de gastrosquisis u onfalocele, entre el 1 de enero de 1998 y el 31 de diciembre de 2006. Se definió el tipo de tratamiento que se les realizó y, de acuerdo con este, se revisaron los resultados; las complicaciones posquirúrgicas, tales como la infección del sitio operatorio, evisceración, sepsis, íleus e hipertensión intraabdominal; el tiempo de inicio de la vía oral y de la nutrición parenteral total (NPT; la duración de la estancia en la unidad de cuidados intensivos y en el hospital. RESULTADOS: se identificaron 55 pacientes, 32 con gastrosquisis y 23 con onfalocele, todos ellos tratados quirúrgicamente. El tipo más frecuente de cirugía fue el cierre primario (56,4%; en cuanto al cierre por etapas, el procedimiento más utilizado fue el silo en 21,8% de los niños. En el 75,9% de los pacientes se presentó alguna complicación, más frecuentemente la sepsis, y cuando se evaluaron las complicaciones asociadas al procedimiento quirúrgico, el porcentaje fue similar para el cierre

    6. Development of novel tasks for studying view-invariant object recognition in rodents: Sensitivity to scopolamine.

      Science.gov (United States)

      Mitchnick, Krista A; Wideman, Cassidy E; Huff, Andrew E; Palmer, Daniel; McNaughton, Bruce L; Winters, Boyer D

      2018-05-15

      The capacity to recognize objects from different view-points or angles, referred to as view-invariance, is an essential process that humans engage in daily. Currently, the ability to investigate the neurobiological underpinnings of this phenomenon is limited, as few ethologically valid view-invariant object recognition tasks exist for rodents. Here, we report two complementary, novel view-invariant object recognition tasks in which rodents physically interact with three-dimensional objects. Prior to experimentation, rats and mice were given extensive experience with a set of 'pre-exposure' objects. In a variant of the spontaneous object recognition task, novelty preference for pre-exposed or new objects was assessed at various angles of rotation (45°, 90° or 180°); unlike control rodents, for whom the objects were novel, rats and mice tested with pre-exposed objects did not discriminate between rotated and un-rotated objects in the choice phase, indicating substantial view-invariant object recognition. Secondly, using automated operant touchscreen chambers, rats were tested on pre-exposed or novel objects in a pairwise discrimination task, where the rewarded stimulus (S+) was rotated (180°) once rats had reached acquisition criterion; rats tested with pre-exposed objects re-acquired the pairwise discrimination following S+ rotation more effectively than those tested with new objects. Systemic scopolamine impaired performance on both tasks, suggesting involvement of acetylcholine at muscarinic receptors in view-invariant object processing. These tasks present novel means of studying the behavioral and neural bases of view-invariant object recognition in rodents. Copyright © 2018 Elsevier B.V. All rights reserved.

    7. Use of the Aromascan(TM) Instrument for Nonsubjective Evaluation of Rodent Spaceflight Hardware

      Science.gov (United States)

      Scribner, K. A.; Steele, M. K.; Hinds, W. E.; Dalton, Bonnie P. (Technical Monitor)

      1997-01-01

      This report describes the verification and utilization of the AromaScan(TM) (Hollis, NH) instrument for the ground-based evaluation of odor containment by various spaceflight habitats developed at NASA's Ames Research Center (ARC). The AromaScan(TM) instrument is an electronic odor detection system consisting of 32 polymer sensors that respond differentially to 10 different chemical groups present in an air sample. The AromaScan(TM) system also includes neural network software for constructing a database of known odors, against which an unknown odor can be compared. At present, the standard method for characterizing rodent odor containment during the development and testing of spaceflight hardware is the use of a human odor assessment panel. However, this can be a very time consuming and costly process, and the results are inherently subjective. The AromaScan(TM) system should produce more consistent and objective results, as well as a cost savings in the long term. To test and verify the AromaScan(TM) instrument, daily air samples will be collected from the exhaust port of rodent habitats, during experiment development tests, then injected into the instrument and used to create a database of recognizable odors. Human sniff tests will be performed in conjunction with the AromaScan(TM) analysis, and the results will be correlated. We will then teach the neural network to differentiate between an acceptable and an unacceptable odor profile, as defined by the human sniff test, and to be able to accurately identify an odor that would not pass a sniff panel. The results of our efforts will be to verify that the AromaScan(TM) system is a valuable alternative to human sniff panel assessments for the early iterative process of designing and testing rodent waste filters for spaceflight. Acceptance by a human panel will remain one of the final criteria for successful rodent habitat development.

    8. Novel Treatment Approach for Deep Palmoplantar Warts Using Long-Pulsed 1064-nm Nd:YAG Laser and a Moisturizing Cream Without Prior Paring of the Wart Surface.

      Science.gov (United States)

      Alshami, Mohammad Ali; Mohana, Mona Jameel

      2016-10-01

      The present study aimed to assess the safety and efficacy of palmoplantar wart removal using long-pulsed 1064-nm Nd:YAG laser after application of a moisturizing cream. Previously described laser treatments for wart removal are associated with negative side effects and need to pare the warts before laser treatment. Two hundred forty patients (142 males, 98 females) were treated for 1-40 palmoplantar warts by long-pulsed 1064-nm Nd:YAG laser (spot size 4-6 mm, pulse duration 20 msec, fluence 200 J/cm 2 ) after covering the wart surface with a thin film of a moisturizing cream. The endpoint was lesion graying or whitening with or without development of a hemorrhagic bulla beneath the treated wart. Color photographs were taken before and immediately after each laser session and at 1, 4, and 16 weeks after the last session. The overall clearance rate was 97%, with 90% of treated patients cured after one session, 4% after two, and 3% after three. Clearance rate after three laser sessions decreased linearly with the number of warts from 100% to 95%. Less accessible wart location in interdigital spaces also decreased the cure rate after three sessions from 100% to 95%. Additionally, warts became more difficult to eradicate as they aged. Remission lasted up to 6 years, and complications were mild and infrequent (17.5%). This novel method is effective in removing palmoplantar warts. It is easier, time-saving, and safer than other methods described in previous studies conducted with ablative or nonablative lasers.

    9. Pesquería y biología de Rhinobatos percellens (Rajiformes: Rhinobatidae capturados por la pesquería artesanal de playa La Pared, Venezuela

      Directory of Open Access Journals (Sweden)

      Alejandro Tagliafico

      2013-03-01

      Full Text Available Rhinobatos percellens es capturada en Venezuela por la flota artesanal que opera con redes de fondo. Está clasificada por la IUCN como casi amenazada, y no existen estudios sobre su biología o pesquería en el país. Por ello, se analizaron desembarques de la pesca artesanal de playa la Pared (isla de Margarita durante enero-diciembre 2007. A cada ejemplar capturado se le determinó la longitud total, sexo y madurez. Fueron analizados 210 ejemplares, 159 hembras y 51 machos. El 81% de los ejemplares se encontraban maduros y un 27% de este grupo correspondió a hembras grávidas. La talla media de madurez sexual quedó ubicada en 51 y 52cm para hembras y machos, respectivamente. Se detectaron hembras maduras todo el año, y hembras grávidas en siete meses. Fueron analizados 96 embriones con tallas entre 2-19cm, siendo la fecundidad máxima cuatro embriones. La variación de las longitudes de los embriones entre los meses del año indican dos picos máximos de alumbramiento al año pero no existe una sincronía en la cópula ya que la especie se reproduce prácticamente todo el año. Se recomienda elaborar regulaciones pesqueras que incluyan una talla mínima de captura en función de la talla de madurez señalada y liberar las hembras grávidas al agua.

    10. Developmental toxicity of engineered nanomaterials in rodents

      Energy Technology Data Exchange (ETDEWEB)

      Ema, Makoto, E-mail: ema-makoto@aist.go.jp; Gamo, Masashi; Honda, Kazumasa

      2016-05-15

      We summarized significant effects reported in the literature on the developmental toxicity of engineered nanomaterials (ENMs) in rodents. The developmental toxicity of ENMs included not only structural abnormalities, but also death, growth retardation, and behavioral and functional abnormalities. Most studies were performed on mice using an injection route of exposure. Teratogenic effects were indicated when multi-walled carbon nanotubes (MWCNTs), single-walled carbon nanotubes (SWCNTs), and TiO{sub 2}-nanoparticles were administered to mice during early gestation. Reactive oxygen species levels were increased in placentas and malformed fetuses and their placentas after prenatal exposure to MWCNTs and SWCNTs, respectively. The pre- and postnatal mortalities and growth retardation in offspring increased after prenatal exposure to ENMs. Histopathological and functional abnormalities were also induced in placentas after prenatal exposure to ENMs. Maternal exposure to ENMs induced behavioral alterations, histopathological and biochemical changes in the central nervous system, increased susceptibility to allergy, transplacental genotoxicity, and vascular, immunological, and reproductive effects in offspring. The size- and developmental stage-dependent placental transfer of ENMs was noted after maternal exposure. Silver accumulated in the visceral yolk sac after being injected with Ag-NPs during early gestation. Although currently available data has provided initial information on the potential developmental toxicity of ENMs, that on the developmental toxicity of ENMs is still very limited. Further studies using well-characterized ENMs, state-of the-art study protocols, and appropriate routes of exposure are required in order to clarify these developmental effects and provide information suitable for risk assessments of ENMs. - Highlights: • We review the developmental toxicity studies of engineered nanomaterials (ENMs). • Various developmental endpoints have been

    11. Comparación de la educación por pares y por profesionales de la salud para mejorar el conocimiento, percepción y la conducta sexual de riesgo en adolescentes

      Directory of Open Access Journals (Sweden)

      Sixto Sánchez C

      2003-10-01

      Full Text Available Objetivo: Comparar la educación por pares frente a la educación por profesionales de a consultorios de planificación familiar de dos hospitales de Lima, Perú. Material y Métodos: Estudio experimental simple ciego realizado en 1998 en los consultorios de planificación familiar del Hospital Dos de Mayo y el Instituto Materno Perinatal de Lima, Perú. Después del consentimiento, se asignó aleatoriamente a 206 adolescentes consideradas de riesgo a una de las dos intervenciones educativas y luego fueron invitadas a regresar al final del tercer mes para reevaluar sus conocimientos, actitudes y conducta sexual de riesgo. Se usó la prueba de los signos, Mann Whitney y análisis de Covarianza para comparar los puntajes de los cuestionarios de conocimiento, percepción de riesgo y conducta sexual de riesgo después de la intervención educativa. Resultados: 89 (84% de 106 adolescentes asignadas al grupo de educación por pares y 70 (70% de las 100 asignadas al grupo de educación por profesionales de la salud (p=0,02 regresaron a la evaluación postintervención. El mejoramiento del nivel de conocimiento fue significativamente mayor (p=0,047 en el grupo de educación por pares que en el grupo capacitado por profesionales de la salud; sin embargo, esta significancia disminuyó (p=0,07 cuando se usó análisis de covarianza para controlar el puntaje obtenido antes de la intervención. El mejoramiento de la percepción y conductas de riesgo fue mayor en el grupo de pares pero esta diferencia no fue significativa. Conclusiones: La educación por pares demostró ser más efectiva en mejorar los conocimientos en las adolescentes y el seguimiento fue mejor en este grupo por lo que debe ser promovida como una estrategia para disminuir la prevalencia de infecciones de transmisión sexual en esta población.

    12. (-)-α-Bisabolol reduces orofacial nociceptive behavior in rodents.

      Science.gov (United States)

      Melo, Luana Torres; Duailibe, Mariana Araújo Braz; Pessoa, Luciana Moura; da Costa, Flávio Nogueira; Vieira-Neto, Antonio Eufrásio; de Vasconcellos Abdon, Ana Paula; Campos, Adriana Rolim

      2017-02-01

      The purposes of this study were to evaluate the anti-nociceptive effect of oral and topical administration of (-)-α-bisabolol (BISA) in rodent models of formalin- or cinnamaldehyde-induced orofacial pain and to explore the inhibitory mechanisms involved. Orofacial pain was induced by injecting 1.5% formalin into the upper lip of mice (20 μL) or into the temporomandibular joint (TMJ) of rats (50 μL). In another experiment, orofacial pain was induced with cinnamaldehyde (13.2 μg/lip). Nociceptive behavior was proxied by time (s) spent rubbing the injected area and by the incidence of head flinching. BISA (100, 200, or 400 mg/kg p.o. or 50, 100, or 200 mg/mL topical) or vehicle was administered 60 min before pain induction. The two formulations (lotion and syrup) were compared with regard to efficacy. The effect of BISA remained after incorporation into the formulations, and nociceptive behavior decreased significantly in all tests. The high binding affinity observed for BISA and TRPA1 in the molecular docking study was supported by in vivo experiments in which HC-030031 (a TRPA1 receptor antagonist) attenuated pain in a manner qualitatively and quantitatively similar to that of BISA. Blockers of opioid receptors, NO synthesis, and K + ATP channels did not affect orofacial pain, nor inhibit the effect of BISA. In conclusion, BISA had a significant anti-nociceptive effect on orofacial pain. The effect may in part be due to TRPA1 antagonism. The fact that the effect of BISA remained after incorporation into oral and topical formulations suggests that the compound may be a useful adjuvant in the treatment of orofacial pain.

    13. Lassa fever or lassa hemorrhagic fever risk to humans from rodent-borne zoonoses.

      Science.gov (United States)

      El-Bahnasawy, Mamdouh M; Megahed, Laila Abdel-Mawla; Abdalla Saleh, Hala Ahmed; Morsy, Tosson A

      2015-04-01

      Viral hemorrhagic fevers (VHFs) typically manifest as rapidly progressing acute febrile syndromes with profound hemorrhagic manifestations and very high fatality rates. Lassa fever, an acute hemorrhagic fever characterized by fever, muscle aches, sore throat, nausea, vomiting, diarrhea and chest and abdominal pain. Rodents are important reservoirs of rodent-borne zoonosis worldwide. Transmission rodents to humans occur by aerosol spread, either from the genus Mastomys rodents' excreta (multimammate rat) or through the close contact with infected patients (nosocomial infection). Other rodents of the genera Rattus, Mus, Lemniscomys, and Praomys are incriminated rodents hosts. Now one may ask do the rodents' ectoparasites play a role in Lassa virus zoonotic transmission. This paper summarized the update knowledge on LHV; hopping it might be useful to the clinicians, nursing staff, laboratories' personals as well as those concerned zoonoses from rodents and rodent control.

    14. Old World hantaviruses in rodents in New Orleans, Louisiana.

      Science.gov (United States)

      Cross, Robert W; Waffa, Bradley; Freeman, Ashley; Riegel, Claudia; Moses, Lina M; Bennett, Andrew; Safronetz, David; Fischer, Elizabeth R; Feldmann, Heinz; Voss, Thomas G; Bausch, Daniel G

      2014-05-01

      Seoul virus, an Old World hantavirus, is maintained in brown rats and causes a mild form of hemorrhagic fever with renal syndrome (HFRS) in humans. We captured rodents in New Orleans, Louisiana and tested them for the presence of Old World hantaviruses by reverse transcription polymerase chain reaction (RT-PCR) with sequencing, cell culture, and electron microscopy; 6 (3.4%) of 178 rodents captured--all brown rats--were positive for a Seoul virus variant previously coined Tchoupitoulas virus, which was noted in rodents in New Orleans in the 1980s. The finding of Tchoupitoulas virus in New Orleans over 25 years since its first discovery suggests stable endemicity in the city. Although the degree to which this virus causes human infection and disease remains unknown, repeated demonstration of Seoul virus in rodent populations, recent cases of laboratory-confirmed HFRS in some US cities, and a possible link with hypertensive renal disease warrant additional investigation in both rodents and humans.

    15. Thieving rodents as substitute dispersers of megafaunal seeds

      Science.gov (United States)

      Jansen, Patrick A.; Hirsch, Ben T.; Emsens, Willem-Jan; Zamora-Gutierrez, Veronica; Wikelski, Martin; Kays, Roland

      2012-01-01

      The Neotropics have many plant species that seem to be adapted for seed dispersal by megafauna that went extinct in the late Pleistocene. Given the crucial importance of seed dispersal for plant persistence, it remains a mystery how these plants have survived more than 10,000 y without their mutualist dispersers. Here we present support for the hypothesis that secondary seed dispersal by scatter-hoarding rodents has facilitated the persistence of these large-seeded species. We used miniature radio transmitters to track the dispersal of reputedly megafaunal seeds by Central American agoutis, which scatter-hoard seeds in shallow caches in the soil throughout the forest. We found that seeds were initially cached at mostly short distances and then quickly dug up again. However, rather than eating the recovered seeds, agoutis continued to move and recache the seeds, up to 36 times. Agoutis dispersed an estimated 35% of seeds for >100 m. An estimated 14% of the cached seeds survived to the next year, when a new fruit crop became available to the rodents. Serial video-monitoring of cached seeds revealed that the stepwise dispersal was caused by agoutis repeatedly stealing and recaching each other’s buried seeds. Although previous studies suggest that rodents are poor dispersers, we demonstrate that communities of rodents can in fact provide highly effective long-distance seed dispersal. Our findings suggest that thieving scatter-hoarding rodents could substitute for extinct megafaunal seed dispersers of tropical large-seeded trees. PMID:22802644

    16. Ames Life Science Data Archive: Translational Rodent Research at Ames

      Science.gov (United States)

      Wood, Alan E.; French, Alison J.; Ngaotheppitak, Ratana; Leung, Dorothy M.; Vargas, Roxana S.; Maese, Chris; Stewart, Helen

      2014-01-01

      The Life Science Data Archive (LSDA) office at Ames is responsible for collecting, curating, distributing and maintaining information pertaining to animal and plant experiments conducted in low earth orbit aboard various space vehicles from 1965 to present. The LSDA will soon be archiving data and tissues samples collected on the next generation of commercial vehicles; e.g., SpaceX & Cygnus Commercial Cargo Craft. To date over 375 rodent flight experiments with translational application have been archived by the Ames LSDA office. This knowledge base of fundamental research can be used to understand mechanisms that affect higher organisms in microgravity and help define additional research whose results could lead the way to closing gaps identified by the Human Research Program (HRP). This poster will highlight Ames contribution to the existing knowledge base and how the LSDA can be a resource to help answer the questions surrounding human health in long duration space exploration. In addition, it will illustrate how this body of knowledge was utilized to further our understanding of how space flight affects the human system and the ability to develop countermeasures that negate the deleterious effects of space flight. The Ames Life Sciences Data Archive (ALSDA) includes current descriptions of over 700 experiments conducted aboard the Shuttle, International Space Station (ISS), NASA/MIR, Bion/Cosmos, Gemini, Biosatellites, Apollo, Skylab, Russian Foton, and ground bed rest studies. Research areas cover Behavior and Performance, Bone and Calcium Physiology, Cardiovascular Physiology, Cell and Molecular Biology, Chronobiology, Developmental Biology, Endocrinology, Environmental Monitoring, Gastrointestinal Physiology, Hematology, Immunology, Life Support System, Metabolism and Nutrition, Microbiology, Muscle Physiology, Neurophysiology, Pharmacology, Plant Biology, Pulmonary Physiology, Radiation Biology, Renal, Fluid and Electrolyte Physiology, and Toxicology. These

    17. Functionally-ecological role of biodiversity of small rodents population to ionizing radiation response

      International Nuclear Information System (INIS)

      Grigorkina, E.B.; Olenev, G.V.; Tarasov, O.V.

      2014-01-01

      Full text : In the present work it is aimed to show the results of investigations of radioresistance and biological effects of acute irradiation in laboratory experiment and the specific rate of 90Sr accumulation in the bone tissue of rodents of alternative types of ontogeny development. It is used the functional ontogeny approach, which supposes to divide natural population of mice and voles into groups of individuals with the same functional status and with the uniform patterns of growth or maturation rate as well as whether they participate in reproduction

    18. La percepción de la violencia entre pares en contextos escolares: un estudio cualitativo Violence Among Peers' Perception In Educative Contexts: A Qualitative Study

      Directory of Open Access Journals (Sweden)

      Teresa Ana Veccia

      2008-12-01

      Full Text Available La violencia ha ido incrementándose en los últimos tiempos en distintos niveles y países. La misma es multideterminada por factores históricos, comunitarios, institucionales, familiares e individuales. Dentro de este amplio contexto recortamos el problema de la violencia en las escuelas, y más específicamente del maltrato sostenido entre los niños. Este tipo de maltrato constituye una perturbación en las relaciones entre los miembros de un grupo y es expresión de la violencia interpersonal. Cuando estas relaciones agresivas se transforman en una rígida configuración dominante-dominado que se perpetúa en el tiempo se denomina "bullying" y trae serias consecuencias psicológicas y sociales para sus implicados. En el presente artículo se exponen los resultados de la primera fase cualitativa de una investigación sobre el maltrato entre pares en el ámbito escolar. Se busca comprender e interpretar este fenómeno tal como la perciben los docentes, directivos y personal auxiliar de una escuela de la CABA.The violence has increased in different levels and countries during the last years. This problem is caused by historic, institutional, family and personal components. In this article we focused on the violence in schools and more specific the violence among children. This kind of maltreatment is a perturbation of the relationship among the members of a group, and is an expression of the interpersonal violence. When these aggressiveness relationships become in a rigid configuration dominate-dominated and persist in time, these are known as bullying. These type of behaviors bring serious psychological and social consequences. This article has used a qualitative methodology and has the aim of understanding and interpreting the reality of bullying from the perception of the adults who belong to one of the schools where the research has taken place.

    19. Estudio de corrosión galvánica en pares latón/acero inoxidable y latón/fundición de hierro

      Directory of Open Access Journals (Sweden)

      Ohanian, M.

      2011-08-01

      Full Text Available Corrosion attack in heat exchanger systems is a topic of main interest for the maintenance in each industrial plant. These are multigalvanic systems with particular geometric and fluidodynamic complexity. Corrosive damages include zinc selective dealeation in copper alloys. In order to explain zinc dealeation attack, this paper deals with laboratory scale testing, characterization and interactions between two copper and zinc alloys (Yellow brass –UNS C268– and Admiralty brass –UNS C443– compared to AISI 316 stainless steel and cast iron. The tests were performed at 20 °C in 1.5 % NaCl and 1.5 % Na2SO4 solutions, pH 8 and each material was characterized by potentiodynamic sweeps. The couples are analyzed by studying transient galvanic currents. We conclude about the cause of the analyzed pathology, brass protection potential ranges and its coupling compatibility with other metals.

      El ataque por corrosión en los sistemas intercambiadores de calor constituye un problema para el mantenimiento de cualquier planta industrial. Se trata de sistemas multigalvánicos con particular complejidad geométrica y fluidodinámica. Las patologías corrosivas incluyen el fenómeno de dealeación selectiva de cinc en las aleaciones de cobre. A fin de explicar un caso particular de ataque por decinficación (deterioro en placa de intercambiador de calor de tubos de inoxidable, el presente trabajo aborda en ensayos a escala de laboratorio, la caracterización e interacciones entre dos aleaciones de cobre y cinc, (Yellow brass –UNS C268– y Admiralty brass –UNS C443–, respecto a acero inoxidable AISI 316 y fundición gris de hierro. Los ensayos se realizan a 20 °C en disoluciones de NaCl 1,5 % y Na2SO4 1,5 % y pH 8. Se caracterizan electroquímicamente las aleaciones y materiales involucrados mediante barridos potenciodinámicos. Los pares galvánicos formados se analizan mediante el

    20. Associação da atividade física de adolescentes, familiares e pares: uma revisão sistemática

      Directory of Open Access Journals (Sweden)

      Thiago Silva Piola

      2015-06-01

      Full Text Available Objetivo: Analisar a associação entre a atividade física (AF de pais, irmãos e pares à AF de adolescentes brasileiros por meio de uma revisão sistemática da literatura. Métodos: Realizou-se revisão sistemática em duas etapas, em junho de 2013 e fevereiro de 2014, nas bases de dados PubMed/MEDLINE, Web of Science, EBSCO e LILACS, utilizando-se quatro grupos de descritores, sendo estes “influência de pais e irmãos”, “atividade física”, “tipo de amostra” e “nacionalidade”, nos idiomas inglês e português, que atendesse aos seguintes critérios: (i indivíduos saudáveis; (ii adolescentes brasileiros; (iii estudos abordando a AF; e (iv estudos publicados entre janeiro de 2008 e fevereiro de 2014. Resultados: A busca nas bases de dados resultou em 2.094 títulos de artigos potencialmente relevantes, mas apenas 7 atenderam a todos os critérios de inclusão. Há uma associação positiva entre a AF de pais e filhos, porém, ao estratificar por sexo, esta é encontrada apenas no feminino, tanto para a inatividade quanto para estar fisicamente ativo. O apoio social possui grande influência na AF de crianças e adolescentes, no entanto, tal associação não foi encontrada em estudos longitudinais. Conclusão: Existe uma associação positiva entre a atividade física do pai e da mãe com suas filhas, tanto para a inatividade quanto para serem ativos, mas não foram encontradas associações entre os pais e os filhos, fato também observado para com irmãos inativos. O apoio social mostrou-se eficaz para aumentar o nível de atividade física de adolescentes.

    1. Síntesis de un compuesto de polimetacrilato de metilo con nanotubos de carbono de pared múltiple a escala de laboratorio

      Directory of Open Access Journals (Sweden)

      Yuly Méndez

      2009-05-01

      Full Text Available El objetivo del presente trabajo es la síntesis y caracterización térmica de un compuesto de polimetacrilato de metilo (PMMA con nanotubos de carbono de pared múltiple (MWNTs a escala de laboratorio. El compuesto de PMMA con MWNTs fue producido por polimerización in-situ en masa, usando como iniciador Peróxido de Benzoilo (BPO. Previamente a la polimerización, se realizó una reacción entre los MWNT y el BPO para propiciar la formación de radicales libres en la superficie de los MWNT. La concentración de MWNTs fue variada para producir muestras con 0%, 0,1% y 0,5% en peso de MWNT. El compuesto obtenido presenta una adecuada dispersión en la matríz polimérica y propiedades térmicas diferentes a la del PMMA blanco, lo que evidencia la transferencia de propiedades por parte de los MWNTs. El método propuesto es sencillo y de bajo costo, y puede ser usado en una gran variedad de aplicaciones industriales./The purpose of the current work was the lab-scale synthesis and thermal characterization of a Poly(methyl methacrylate-Multi-walled Carbon Nanotube (PMMA-MWNTs composite. The PMMA-MWNTs composite was produced by mass in-situ polymerization, using Benzoyl Peroxide (BPO as initiator. As a previous step to the polymerization, a BPO-MWNTs reaction was performed to trigger the formation of free radicals in the surface of the MWNTs. The MWNT concentration in the composite was varied to produce samples of 0%, 0.1% and 0.5% w/w of MWNTs in PMMA. The produced composites show an adequate dispersion and different thermal properties than the PMMA blank, suggesting a property transfer from the nanoparticles. The proposed production method is simple, of relatively low cost and easily applicable in a variety of industrial applications.

    2. Anatomy and Histology of Rodent and Human Major Salivary Glands

      Science.gov (United States)

      Amano, Osamu; Mizobe, Kenichi; Bando, Yasuhiko; Sakiyama, Koji

      2012-01-01

      Major salivary glands of both humans and rodents consist of three pairs of macroscopic glands: parotid, submandibular, and sublingual. These glands secrete serous, mucous or mixed saliva via the proper main excretory ducts connecting the glandular bodies with the oral cavity. A series of discoveries about the salivary ducts in the 17th century by Niels Stensen (1638–1686), Thomas Wharton (1614–1673), and Caspar Bartholin (1655–1738) established the concept of exocrine secretion as well as salivary glands. Recent investigations have revealed the endocrine functions of parotin and a variety of cell growth factors produced by salivary glands. The present review aims to describe macroscopic findings on the major salivary glands of rodents and the microscopic differences between those of humans and rodents, which review should be of interest to those researchers studying salivary glands. PMID:23209333

    3. MR microscopy of the lung in small rodents

      International Nuclear Information System (INIS)

      Takahashi, Masaya; Kubo, Shigeto; Kiryu, Shigeru; Gee, James; Hatabu, Hiroto

      2007-01-01

      Understanding how the mammalian respiratory system works and how it changes in disease states and under the influence of drugs is frequently pursued in model systems such as small rodents. These have many advantages, including being easily obtained in large numbers as purebred strains. Studies in small rodents are valuable for proof of concept studies and for increasing our knowledge about disease mechanisms. Since the recent developments in the generation of genetically designed animal models of disease, one needs the ability to assess morphology and function in in vivo systems. In this article, we first review previous reports regarding thoracic imaging. We then discuss approaches to take in making use of small rodents to increase MR microscopic sensitivity for these studies and to establish MR methods for clinically relevant lung imaging

    4. Can a native rodent species limit the invasive potential of a non-native rodent species in tropical agroforest habitats?

      Science.gov (United States)

      Stuart, Alexander M; Prescott, Colin V; Singleton, Grant R

      2016-06-01

      Little is known about native and non-native rodent species interactions in complex tropical agroecosystems. We hypothesised that the native non-pest rodent Rattus everetti may be competitively dominant over the invasive pest rodent Rattus tanezumi within agroforests. We tested this experimentally by using pulse removal for three consecutive months to reduce populations of R. everetti in agroforest habitat, and assessed over 6 months the response of R. tanezumi and other rodent species. Following removal, R. everetti individuals rapidly immigrated into removal sites. At the end of the study period, R. tanezumi were larger and there was a significant shift in their microhabitat use with respect to the use of ground vegetation cover following the perturbation of R. everetti. Irrespective of treatment, R. tanezumi selected microhabitat with less tree canopy cover, indicative of severely disturbed habitat, whereas R. everetti selected microhabitat with a dense canopy. Our results suggest that sustained habitat disturbance in agroforests favours R. tanezumi, while the regeneration of agroforests towards a more natural state would favour native species and may reduce pest pressure in adjacent crops. In addition, the rapid recolonisation of R. everetti suggests this species would be able to recover from non-target impacts of short-term rodent pest control. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

    5. Synanthropic rodents as possible reservoirs of shigatoxigenic Escherichia coli strains

      Directory of Open Access Journals (Sweden)

      Ximena eBlanco Crivelli

      2012-11-01

      Full Text Available Shigatoxigenic Escherichia coli (STEC strains are worldwide zoonotic pathogen responsible for different cases of human disease including hemolytic uremic syndrome (HUS. Transmission of STEC to humans occurs through the consumption of food and water contaminated by faeces of carriers and by person-to-person contact.The objective of this study was twofold: (a to investigate whether synanthropic rodents are possible reservoirs of STEC in the urban area and (b whether a particular genus out of synanthropic rodent is the principal carrier of STEC.One hundred forty-five rodents were captured in Buenos Aires City. Screening for stx1/stx2 and rfbO157 was done by PCR from the confluence zone. STEC isolates were further characterized with biochemical tests by standard methods. Additional virulence factors (eae, ehxA and saa were also determined by PCR. Forty-one of the rodents were necropsied and sample of kidney and small and large intestine were taken for histopathological diagnosis. The samples sections were stained with hematoxylin-eosin, and observed by light microscopy to evaluate the systemic involvement of these species in natural infections. STEC was isolated from seven out of twenty seven suspect animals at screening. The following genotypes were found in the STEC strains: stx1/stx2/ehxA (1, stx2 (4, stx2/ehxA (1, stx2/ehxA/eae (1. Neither gross nor microscopic lesions compatible with those produced by Shiga toxin were observed in the studied organs of necropsied rodents.The bivariate analysis including the hundred forty-five rodents data showed that the isolation of STEC is associated positively to Rattus genus. This synanthropic species may play a role in the transmissibility of the agent thus being a risk to the susceptible population. Their control should be included specifically in actions to dismiss the contamination of food and water by STEC in the urban area, as additional strategies for epidemiological control.

    6. Multiple infections of rodents with zoonotic pathogens in Austria.

      Science.gov (United States)

      Schmidt, Sabrina; Essbauer, Sandra S; Mayer-Scholl, Anne; Poppert, Sven; Schmidt-Chanasit, Jonas; Klempa, Boris; Henning, Klaus; Schares, Gereon; Groschup, Martin H; Spitzenberger, Friederike; Richter, Dania; Heckel, Gerald; Ulrich, Rainer G

      2014-07-01

      Rodents are important reservoirs for a large number of zoonotic pathogens. We examined the occurrence of 11 viral, bacterial, and parasitic agents in rodent populations in Austria, including three different hantaviruses, lymphocytic choriomeningitis virus, orthopox virus, Leptospira spp., Borrelia spp., Rickettsia spp., Bartonella spp., Coxiella burnetii, and Toxoplasma gondii. In 2008, 110 rodents of four species (40 Clethrionomys glareolus, 29 Apodemus flavicollis, 26 Apodemus sylvaticus, and 15 Microtus arvalis) were trapped at two rural sites in Lower Austria. Chest cavity fluid and samples of lung, spleen, kidney, liver, brain, and ear pinna skin were collected. We screened selected tissue samples for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, Leptospira, Borrelia, Rickettsia, Bartonella spp., C. burnetii, and T. gondii by RT-PCR/PCR and detected nucleic acids of Tula hantavirus, Leptospira spp., Borrelia afzelii, Rickettsia spp., and different Bartonella species. Serological investigations were performed for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, and Rickettsia spp. Here, Dobrava-Belgrade hantavirus-, Tula hantavirus-, lymphocytic choriomeningitis virus-, orthopox virus-, and rickettsia-specific antibodies were demonstrated. Puumala hantavirus, C. burnetii, and T. gondii were neither detected by RT-PCR/PCR nor by serological methods. In addition, multiple infections with up to three pathogens were shown in nine animals of three rodent species from different trapping sites. In conclusion, these results show that rodents in Austria may host multiple zoonotic pathogens. Our observation raises important questions regarding the interactions of different pathogens in the host, the countermeasures of the host's immune system, the impact of the host-pathogen interaction on the fitness of the host, and the spread of infectious agents among wild rodents and from those to other animals or humans.

    7. Normas percibidas por los estudiantes universitarios acerca de sus pares y el uso de drogas en Bogotá, Colombia Normas percebidas pelos estudantes universitários acerca dos seus pares e o uso de drogas em Bogotá, Colômbia Perceived norms among university students about their peers and drug use in Bogota, Colombia

      Directory of Open Access Journals (Sweden)

      Luz Stella Medina Matallana

      2009-01-01

      Full Text Available Este estudio tuvo como objetivo estimar la diferencia entre las normas percibidas sobre uso de drogas en universitarios y sus pares, entre 18 a 24 años, de las áreas de salud y educación. Se trata de un estudio transversal, por encuesta y cuestionario autoaplicado anónimo. Participaron 365 estudiantes. En el último año, la proporción de consumo real de tabaco fue 43,6%, de alcohol 96,2%, de marihuana 8,2%; y 2,2%, de cocaína. La norma percibida de la proporción de consumo de tabaco el último año fue 78,9%, alcohol 88,3%, marihuana 35,4% y 20,9% cocaína. La proporción de consumo real de alcohol entre los estudiantes y la norma percibida por ellos estuvieron muy próximas; para el tabaco, marihuana y cocaína la percepción estuvo sobreestimada. De las drogas de acceso fácil o muy fácil en el campus, se encontró una subestimación para cigarrillo y cocaína, y sobreestimación para marihuana. Se concluye que los universitarios sobrestiman el consumo de tabaco, marihuana y cocaína, parte de sus pares, y tienen una percepción exacta del consumo de alcohol. La sustancia de consumo más sobreestimada de los últimos doce meses fue el tabaco.Com este trabalho objetivou-se estimar a diferença entre as normas percebidas sobre o uso de drogas pelos estudantes universitários e os seus pares, com idades entre 18 e 24 anos, das faculdades de educação e saúde. É um estudo transversal, baseado em censo e questionário autoadministrado, sem identificação do respondente. Participaram 365 estudantes. Quanto aos resultados, vê-se que a proporção do consumo de tabaco no último ano foi 43,6%; álcool 96,2%, maconha 8,2% e 2,2% cocaína. A norma percebida para a proporção do consumo de tabaco no último ano foi de 78,9%, álcool 88,3%, maconha 35,4% e 20,9% para a cocaína. A proporção do consumo de bebidas alcoólicas e a norma percebida estiveram muito próximas, para o consumo de tabaco esteve sobreestimada. Para o acesso f

    8. Discovery of Novel Alphacoronaviruses in European Rodents and Shrews

      Directory of Open Access Journals (Sweden)

      Theocharis Tsoleridis

      2016-03-01

      Full Text Available Eight hundred and thirteen European rodents and shrews encompassing seven different species were screened for alphacoronaviruses using PCR detection. Novel alphacoronaviruses were detected in the species Rattus norvegicus, Microtus agrestis, Sorex araneus and Myodes glareolus. These, together with the recently described Lucheng virus found in China, form a distinct rodent/shrew-specific clade within the coronavirus phylogeny. Across a highly conserved region of the viral polymerase gene, the new members of this clade were up to 22% dissimilar at the nucleotide level to the previously described Lucheng virus. As such they might represent distinct species of alphacoronaviruses. These data greatly extend our knowledge of wildlife reservoirs of alphacoronaviruses.

    9. Modelación del contacto entre dos pares de dientes en las coronas de molinos de caña//Modeling of contact between two pairs of teeth in the sugar cane mills gears

      Directory of Open Access Journals (Sweden)

      Abdel Mendoza‐Fernández

      2013-09-01

      Full Text Available En el trabajo se propone un mecanismo equivalente para la modelación del funcionamiento de las coronas de molino de caña de azúcar cuando teóricamente hay dos pares de dientes en contacto. A través del análisis de movilidad del mecanismo se demuestra que no es posible el contacto simultaneo entre dos pares de dientes y que el coeficiente de recubrimiento en estos engranes es igual o menor que la unidad. A partir de los resultados del análisis cinemático del contacto entre un par de dientes, y combinándolo con la modelación del contacto entre dos pares de dientes se demuestra que el coeficiente de recubrimiento real en estos engranajes es menor que la unidad y se producen impactos entre los dientes al inicio del contacto.Palabras claves: molinos de caña, coronas de molinos, coeficiente de recubrimiento, engranajes._________________________________________________________________________________AbstractThe paper proposes an equivalent mechanism for modeling the functioning of the crowns of sugar cane mill when theoretically there are two pairs of teeth in contact. Through mobility analysis of the mechanism is demonstrated that is not possible the simultaneous contact between two pairs of teeth and that the coating coefficient of these gears is equal or less than unity. Combining kinematic analysis results for the contact between a pair of teeth with the modeling the contact between two pairs of teeth, it is demonstrated that gear ratio of these gears is less than unity and impacts occur between the teeth at the start of contact.Key words: sugar cane mills, sugar cane mills gears, contact ratio, gears.

    10. Characterization of the interaction layer in diffusion couples U-Mo-Zr/Al and U-Mo-Zr/Al-A356 at 550 C degrees; Caracterizacion de la zona de interaccion en pares de difusion a 550 grados C U-Mo-Zr/Al y U-Mo-Zr/Al-A356

      Energy Technology Data Exchange (ETDEWEB)

      Komar Varela, Carolina; Arico, Sergio; Mirandou, Marcela; Balart, Silvia; Gribaudo, Luis [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Materiales; com, carolinakomar@gmail

      2007-07-01

      Out-of-pile diffusion experiments were performed between U-7 wt.% Mo-1 wt.% Zr and Al or Al A356 (7,1 wt.% Si) at 550 C degrees. In this work morphological characterization and phase identification on both interaction layers are presented. They were carried out by the use of different techniques: optical and scanning electron microscopy, X-ray diffraction and WDS microanalysis. In the interaction layer U-7 wt.% Mo-1 wt.% Zr/Al, the phases UAl{sub 3}, UAl{sub 4}, Al{sub 20}Mo{sub 2}U and Al{sub 43}Mo{sub 4}U{sub 6} were identified. Similar results in the interaction layer of the U-7 % Mo/Al at 580 C degrees were previously obtained. In the interaction layer U-7 wt.% Mo-1 wt.% Zr/Al A356, the phases U(Al,Si){sub 3} with 25 at.% Si and Si{sub 5}U{sub 3} were identified. This last phase, with a higher Si concentration, was identified with X-ray diffraction synchrotron radiation performed at the National Synchrotron Light Laboratory, Campinas, Brazil. (author) [Spanish] Se realizaron experiencias fuera de reactor en pares de difusion quimica U-7 % Mo-1 % Zr/Al y U-7 % Mo-1 % Zr/Al A356. En este trabajo se presentan los resultados de la caracterizacion morfologica e identificacion de fases presentes en la zona de interaccion que se forma al ser sometidos a un tratamiento isotermico de 1,5 h a 550 grados C. Las tecnicas utilizadas fueron: microscopia optica y electronica de barrido, difraccion de rayos X y microanalisis cuantitativo por sonda electronica. En la zona de interaccion correspondiente al par U-7 % Mo-1 % Zr/Al se identificaron las fases UAl{sub 3}, UAl{sub 4}, Al{sub 20}Mo{sub 2}U y Al{sub 43}Mo{sub 4}U{sub 6}. Estas cuatro fases fueron identificadas en pares U-7 % Mo/Al a 580 grados C en trabajos anteriores. En la zona de interaccion correspondiente al par U-7 % Mo-1 % Zr/Al A356 se identificaron las fases U(Al,Si){sub 3} (con una concentracion de 25 %at.Si) y Si{sub 5}U{sub 3}. Este compuesto rico en Si solo pudo ser identificado mediante la utilizacion de

    11. Farmer survey in the hinterland of Kisangani (Democratic Republic of Congo) on rodent crop damage and rodent control techniques used

      DEFF Research Database (Denmark)

      Drazo, Nicaise Amundala; Kennis, Jan; Leirs, Herwig

      2008-01-01

      We conducted a survey on rodent crop damage among farmers in the hinterland of Kisangani (Democratic Republic of Congo). We studied the amount of crop damage, the rodent groups causing crop damage, the growth stages affected and the control techniques used. We conducted this survey in three...... municipalities using a standard questionnaire form translated into local languages, between November 2005 and June 2006 and during July 2007. We used the Quotas method and interviewed 70 households per municipality. Farmers indicated rodent groups implicated in crop damage on color photographs. Two types...... of survey techniques were used: individual and focus-group surveys. The sugar cane rat, Thryonomys sp. and Lemniscomys striatus caused most damage to crops, but inside granaries, Rattus rattus was the primary pest species eating stored food supplies and causing damage to stored goods. Cassava and maize were...

    12. The G protein-coupled receptor subset of the dog genome is more similar to that in humans than rodents.

      Science.gov (United States)

      Haitina, Tatjana; Fredriksson, Robert; Foord, Steven M; Schiöth, Helgi B; Gloriam, David E

      2009-01-15

      The dog is an important model organism and it is considered to be closer to humans than rodents regarding metabolism and responses to drugs. The close relationship between humans and dogs over many centuries has lead to the diversity of the canine species, important genetic discoveries and an appreciation of the effects of old age in another species. The superfamily of G protein-coupled receptors (GPCRs) is one of the largest gene families in most mammals and the most exploited in terms of drug discovery. An accurate comparison of the GPCR repertoires in dog and human is valuable for the prediction of functional similarities and differences between the species. We searched the dog genome for non-olfactory GPCRs and obtained 353 full-length GPCR gene sequences, 18 incomplete sequences and 13 pseudogenes. We established relationships between human, dog, rat and mouse GPCRs resolving orthologous pairs and species-specific duplicates. We found that 12 dog GPCR genes are missing in humans while 24 human GPCR genes are not part of the dog GPCR repertoire. There is a higher number of orthologous pairs between dog and human that are conserved as compared with either mouse or rat. In almost all cases the differences observed between the dog and human genomes coincide with other variations in the rodent species. Several GPCR gene expansions characteristic for rodents are not found in dog. The repertoire of dog non-olfactory GPCRs is more similar to the repertoire in humans as compared with the one in rodents. The comparison of the dog, human and rodent repertoires revealed several examples of species-specific gene duplications and deletions. This information is useful in the selection of model organisms for pharmacological experiments.

    13. The G protein-coupled receptor subset of the dog genome is more similar to that in humans than rodents

      Directory of Open Access Journals (Sweden)

      Schiöth Helgi B

      2009-01-01

      Full Text Available Abstract Background The dog is an important model organism and it is considered to be closer to humans than rodents regarding metabolism and responses to drugs. The close relationship between humans and dogs over many centuries has lead to the diversity of the canine species, important genetic discoveries and an appreciation of the effects of old age in another species. The superfamily of G protein-coupled receptors (GPCRs is one of the largest gene families in most mammals and the most exploited in terms of drug discovery. An accurate comparison of the GPCR repertoires in dog and human is valuable for the prediction of functional similarities and differences between the species. Results We searched the dog genome for non-olfactory GPCRs and obtained 353 full-length GPCR gene sequences, 18 incomplete sequences and 13 pseudogenes. We established relationships between human, dog, rat and mouse GPCRs resolving orthologous pairs and species-specific duplicates. We found that 12 dog GPCR genes are missing in humans while 24 human GPCR genes are not part of the dog GPCR repertoire. There is a higher number of orthologous pairs between dog and human that are conserved as compared with either mouse or rat. In almost all cases the differences observed between the dog and human genomes coincide with other variations in the rodent species. Several GPCR gene expansions characteristic for rodents are not found in dog. Conclusion The repertoire of dog non-olfactory GPCRs is more similar to the repertoire in humans as compared with the one in rodents. The comparison of the dog, human and rodent repertoires revealed several examples of species-specific gene duplications and deletions. This information is useful in the selection of model organisms for pharmacological experiments.

    14. Mixed-time parallel evolution in multiple quantum NMR experiments: sensitivity and resolution enhancement in heteronuclear NMR

      International Nuclear Information System (INIS)

      Ying Jinfa; Chill, Jordan H.; Louis, John M.; Bax, Ad

      2007-01-01

      A new strategy is demonstrated that simultaneously enhances sensitivity and resolution in three- or higher-dimensional heteronuclear multiple quantum NMR experiments. The approach, referred to as mixed-time parallel evolution (MT-PARE), utilizes evolution of chemical shifts of the spins participating in the multiple quantum coherence in parallel, thereby reducing signal losses relative to sequential evolution. The signal in a given PARE dimension, t 1 , is of a non-decaying constant-time nature for a duration that depends on the length of t 2 , and vice versa, prior to the onset of conventional exponential decay. Line shape simulations for the 1 H- 15 N PARE indicate that this strategy significantly enhances both sensitivity and resolution in the indirect 1 H dimension, and that the unusual signal decay profile results in acceptable line shapes. Incorporation of the MT-PARE approach into a 3D HMQC-NOESY experiment for measurement of H N -H N NOEs in KcsA in SDS micelles at 50 o C was found to increase the experimental sensitivity by a factor of 1.7±0.3 with a concomitant resolution increase in the indirectly detected 1 H dimension. The method is also demonstrated for a situation in which homonuclear 13 C- 13 C decoupling is required while measuring weak H3'-2'OH NOEs in an RNA oligomer

    15. A rodent malarial model of Plasmodium berghei for the development ...

      African Journals Online (AJOL)

      A rodent malarial model of Plasmodium berghei for the development of pyrimethamine and sulphadoxine-pyrimethamine resistant malaria in mice. ... course approach with 125/6.25mg/kg S/P. The stability of resistance phenotypes, parasite pathogenic disposition and host leukocyte response were also investigated.

    16. seasonal population dynamics of rodents of mount chilalo, arsi ...

      African Journals Online (AJOL)

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      ABSTRACT: A study on seasonal population dynamics of rodents was carried out on Mount. Chilalo from .... vegetation growth, availability of food and water, and ... vegetation (3,300–4,200 masl) (Alemayehu. Mengistu, 1975; APEDO and ABRDP, 2004). The mountain is one of the Afrotropical biodiversity hotspots areas.

    17. Optimizing Cardiovascular Benefits of Exercise: A Review of Rodent Models

      Science.gov (United States)

      Davis, Brittany; Moriguchi, Takeshi; Sumpio, Bauer

      2013-01-01

      Although research unanimously maintains that exercise can ward off cardiovascular disease (CVD), the optimal type, duration, intensity, and combination of forms are yet not clear. In our review of existing rodent-based studies on exercise and cardiovascular health, we attempt to find the optimal forms, intensities, and durations of exercise. Using Scopus and Medline, a literature review of English language comparative journal studies of cardiovascular benefits and exercise was performed. This review examines the existing literature on rodent models of aerobic, anaerobic, and power exercise and compares the benefits of various training forms, intensities, and durations. The rodent studies reviewed in this article correlate with reports on human subjects that suggest regular aerobic exercise can improve cardiac and vascular structure and function, as well as lipid profiles, and reduce the risk of CVD. Findings demonstrate an abundance of rodent-based aerobic studies, but a lack of anaerobic and power forms of exercise, as well as comparisons of these three components of exercise. Thus, further studies must be conducted to determine a truly optimal regimen for cardiovascular health. PMID:24436579

    18. Factors associated with flea infestation among the different rodent ...

      African Journals Online (AJOL)

      Flea infection with the bacterium, Yersinia pestis is acquired from reservoirs which include several rodents and other small mammals. In areas that are endemic of plague, reservoirs of Y. pestis and various flea vectors are responsible for perpetuating existence of the disease. The objective of this cross sectional study was to ...

    19. Energetics and water relations ofN amib desert rodents

      African Journals Online (AJOL)

      and the possible effects of advective fog on the water balance of the .... Table 2 Energy balance of Namib desert rodents in the laboratory on a diet of air-dried bird seed and with, and with, ad lib water. .... responding mercury thermometer.

    20. The Revised Neurobehavioral Severity Scale (NSS-R) for Rodents.

      Science.gov (United States)

      Yarnell, Angela M; Barry, Erin S; Mountney, Andrea; Shear, Deborah; Tortella, Frank; Grunberg, Neil E

      2016-04-08

      Motor and sensory deficits are common following traumatic brain injury (TBI). Although rodent models provide valuable insight into the biological and functional outcomes of TBI, the success of translational research is critically dependent upon proper selection of sensitive, reliable, and reproducible assessments. Published literature includes various observational scales designed to evaluate post-injury functionality; however, the heterogeneity in TBI location, severity, and symptomology can complicate behavioral assessments. The importance of choosing behavioral outcomes that can be reliably and objectively quantified in an efficient manner is becoming increasingly important. The Revised Neurobehavioral Severity Scale (NSS-R) is a continuous series of specific, sensitive, and standardized observational tests that evaluate balance, motor coordination, and sensorimotor reflexes in rodents. The tasks follow a specific order designed to minimize interference: balance, landing, tail raise, dragging, righting reflex, ear reflex, eye reflex, sound reflex, tail pinch, and hindpaw pinch. The NSS-R has proven to be a reliable method differentiating brain-injured rodents from non-brain-injured rodents across many brain injury models. Copyright © 2016 John Wiley & Sons, Inc.

    1. Reproducibility and replicability of rodent phenotyping in preclinical studies

      NARCIS (Netherlands)

      Kafkafi, Neri; Agassi, Joseph; Chesler, Elissa J.; Crabbe, John C.; Crusio, Wim E.; Eilam, David; Gerlai, Robert; Golani, Ilan; Gomez-Marin, Alex; Heller, Ruth; Iraqi, Fuad; Jaljuli, Iman; Karp, Natasha A.; Morgan, Hugh; Nicholson, George; Pfaff, Donald W.; Richter, S. Helene; Stark, Philip B.; Stiedl, Oliver; Stodden, Victoria; Tarantino, Lisa M.; Tucci, Valter; Valdar, William; Williams, Robert W.; Würbel, Hanno; Benjamini, Yoav

      The scientific community is increasingly concerned with the proportion of published “discoveries” that are not replicated in subsequent studies. The field of rodent behavioral phenotyping was one of the first to raise this concern, and to relate it to other methodological issues: the complex

    2. STATUS OF COMMENSAL RODENT -BORNE DISEASES RESEARCH IN INDONESIA

      Directory of Open Access Journals (Sweden)

      Lim Boo Liat

      2012-09-01

      Full Text Available Rodents yang terdapat di rumah-rumah maupun di lapangan mempunyai peranan penting dalam penyebaran penyakit terhadap manusia dan binatang. Dalam tulisan ini disajikan peninjauan kembali literatur tentang penyakit-penyakit yang ditularkan oleh binatang, seperti : plague, scrub and murine typhus, leptospirosis, schistosomiasis, angiostrongyliasis, yang biaya terdapat di Indonesia.

    3. Costs of rodent control in pine regeneration in California

      Science.gov (United States)

      Richard D. Cosens; David Tackle

      1950-01-01

      The control of seed-eating rodents, combined with the proper method of cutting and site preparation, appears essential to get the maximum results of natural seeding of pine. One method of control is by treating the area to be regenerated with lethal bait prior to seedfall. This note describes such a method and costs of treatment for the westside and eastside Sierran...

    4. Blood protozoan parasites of rodents in Jos, Plateau State, Nigerai ...

      African Journals Online (AJOL)

      One hundred and thirty rodents, comprising nine different species caught from seven different locations in Jos, Nigeria, were examined for blood protozoan parasites, and 82(63.08%) were positive, with Plasmodium 63(48.46%), Trypanosoma 4(3.08%), Toxoplasma 6(4.62%), Babesia 7(5.38%) and Anaplasma 2(1.54%).

    5. Andes hantavirus variant in rodents, southern Amazon Basin, Peru.

      Science.gov (United States)

      Razuri, Hugo; Tokarz, Rafal; Ghersi, Bruno M; Salmon-Mulanovich, Gabriela; Guezala, M Claudia; Albujar, Christian; Mendoza, A Patricia; Tinoco, Yeny O; Cruz, Christopher; Silva, Maria; Vasquez, Alicia; Pacheco, Víctor; Ströher, Ute; Guerrero, Lisa Wiggleton; Cannon, Deborah; Nichol, Stuart T; Hirschberg, David L; Lipkin, W Ian; Bausch, Daniel G; Montgomery, Joel M

      2014-02-01

      We investigated hantaviruses in rodents in the southern Amazon Basin of Peru and identified an Andes virus variant from Neacomys spinosus mice. This finding extends the known range of this virus in South America and the range of recognized hantaviruses in Peru. Further studies of the epizoology of hantaviruses in this region are warranted.

    6. Andes Hantavirus Variant in Rodents, Southern Amazon Basin, Peru

      OpenAIRE

      Razuri, Hugo; Tokarz, Rafal; Ghersi, Bruno M.; Salmon-Mulanovich, Gabriela; Guezala, M. Claudia; Albujar, Christian; Mendoza, A. Patricia; Tinoco, Yeny O.; Cruz, Christopher; Silva, Maria; Vasquez, Alicia; Pacheco, Víctor; Ströher, Ute; Guerrero, Lisa Wiggleton; Cannon, Deborah

      2014-01-01

      We investigated hantaviruses in rodents in the southern Amazon Basin of Peru and identified an Andes virus variant from Neacomys spinosus mice. This finding extends the known range of this virus in South America and the range of recognized hantaviruses in Peru. Further studies of the epizoology of hantaviruses in this region are warranted.

    7. Fossil Rodents from Curaçao and Bonaire

      NARCIS (Netherlands)

      Hooijer, D.A.

      1959-01-01

      The fossil remains of rodents described in the present paper are from various localities. The large extinct musk rat Megalomys occurs in reddish-brown phosphatic “oolite” fillings of irregular cavities in a marine limestone found by Mr. P. H. DE BUISONJÉ in the north-western part of the Duivelsklip,

    8. Preliminary report of shrews and rodents in and around Lake ...

      African Journals Online (AJOL)

      Surveys during October 2004 and July 2005, in and around Lake Bogoria National Reserve, Kenya, collected evidence of nine rodent species, and one species of shrew. The diversity of small mammals live-trapped within a single habitat type was low compared to similar studies in Africa. The low diversity may be due to the ...

    9. Emmonsiosis of subterranean rodents (Bathyergidae, Spalacidae) in Africa and Israel

      Czech Academy of Sciences Publication Activity Database

      Hubálek, Zdeněk; Burda, H.; Scharff, A.; Heth, G.; Nevo, E.; Šumbera, R.; Peško, Juraj; Zima, Jan

      2005-01-01

      Roč. 43, č. 8 (2005), s. 691-697 ISSN 1369-3786 Grant - others:DAAD(DE) 323-PPP-sp Institutional research plan: CEZ:AV0Z60930519 Keywords : adiasporomycosis * rodents Subject RIV: EG - Zoology Impact factor: 1.422, year: 2005

    10. The response of human and rodent cells to hyperthermia

      International Nuclear Information System (INIS)

      Roizin-Towle, L.; Pirro, J.P.

      1991-01-01

      Inherent cellular radiosensitivity in vitro has been shown to be a good predictor of human tumor response in vivo. In contrast, the importance of the intrinsic thermosensitivity of normal and neoplastic human cells as a factor in the responsiveness of human tumors to adjuvant hyperthermia has never been analyzed systematically. A comparison of thermal sensitivity and thermo-radiosensitization in four rodent and eight human-derived cell lines was made in vitro. Arrhenius plots indicated that the rodent cells were more sensitive to heat killing than the human, and the break-point was 0.5 degrees C higher for the human than rodent cells. The relationship between thermal sensitivity and the interaction of heat with X rays at low doses was documented by thermal enhancement ratios (TER's). Cells received either a 1 hr exposure to 43 degrees C or a 20 minute treatment at 45 degrees C before exposure to 300 kVp X rays. Thermal enhancement ratios ranged from 1.0 to 2.7 for human cells heated at 43 degrees C and from 2.1 to 5.3 for heat exposures at 45 degrees C. Thermal enhancement ratios for rodent cells were generally 2 to 3 times higher than for human cells, because of the fact that the greater thermosensitivity of rodent cells results in a greater enhancement of radiation damage. Intrinsic thermosensitivity of human cells has relevance to the concept of thermal dose; intrinsic thermo-radiosensitization of a range of different tumor cells is useful in documenting the interactive effects of radiation combined with heat

    11. Nutritional Evaluation of NASA's Rodent Food Bar Diet

      Science.gov (United States)

      Barrett, Joyce E.; Yu, Diane S.; Dalton, Bonnie P.

      2000-01-01

      Tests are being conducted on NASA's rodent Food Bar in preparation for long-term use as the rat and mouse diet aboard the International Space Station. Nutritional analyses are performed after the bars are manufactured and then repeated periodically to determine nutritional stability. The primary factors analyzed are protein, ash, fat, fiber, moisture, amino acids, fatty acids, and minerals. Nutrient levels are compared to values published in the National Research Council's dietary requirements for rodents, and also to those contained in several commonly used commercial rodent lab diets. The Food Bar is manufactured from a powdered diet to which moisture is added as it is processed through an extruder. The bars are dipped into potassium sorbate, vacuum-sealed, and irradiated. In order to determine nutrient changes during extrusion and irradiation, the powdered diet, the non-irradiated bars, and the irradiated bars are all analyzed. We have observed lower values for some nutrients (iodine, vitamin K, and iron) in the Food Bars compared with NRC requirements. Many nutrients in the Food Bars are contained at a higher level than levels in the NRC requirements. An additional factor we are investigating is the 26% moisture level in the Food Bars, which drops to about 15% within a week, compared to a stable 10% moisture in many standard lab chow diets. In addition to the nutritional analyses, the food bar is being fed to several strains of rats and mice, and feeding study and necropsy results are being observed (Barrett et al, unpublished data). Information from the nutritional analyses and from the rodent studies will enable us to recommend the formulation that will most adequately meet the rodent Food Bar requirements for long-term use aboard the Space Station.

    12. Respiratory insufficiency correlated strongly with mortality of rodents infected with West Nile virus.

      Directory of Open Access Journals (Sweden)

      John D Morrey

      Full Text Available West Nile virus (WNV disease can be fatal for high-risk patients. Since WNV or its antigens have been identified in multiple anatomical locations of the central nervous system of persons or rodent models, one cannot know where to investigate the actual mechanism of mortality without careful studies in animal models. In this study, depressed respiratory functions measured by plethysmography correlated strongly with mortality. This respiratory distress, as well as reduced oxygen saturation, occurred beginning as early as 4 days before mortality. Affected medullary respiratory control cells may have contributed to the animals' respiratory insufficiency, because WNV antigen staining was present in neurons located in the ventrolateral medulla. Starvation or dehydration would be irrelevant in people, but could cause death in rodents due to lethargy or loss of appetite. Animal experiments were performed to exclude this possibility. Plasma ketones were increased in moribund infected hamsters, but late-stage starvation markers were not apparent. Moreover, daily subcutaneous administration of 5% dextrose in physiological saline solution did not improve survival or other disease signs. Therefore, infected hamsters did not die from starvation or dehydration. No cerebral edema was apparent in WNV- or sham-infected hamsters as determined by comparing wet-to-total weight ratios of brains, or by evaluating blood-brain-barrier permeability using Evans blue dye penetration into brains. Limited vasculitis was present in the right atrium of the heart of infected hamsters, but abnormal electrocardiograms for several days leading up to mortality did not occur. Since respiratory insufficiency was strongly correlated with mortality more than any other pathological parameter, it is the likely cause of death in rodents. These animal data and a poor prognosis for persons with respiratory insufficiency support the hypothesis that neurological lesions affecting respiratory

    13. Assignment of adenosine deaminase complexing protein (ADCP) gene(s) to human chromosome 2 in rodent-human somatic cell hybrids.

      Science.gov (United States)

      Herbschleb-Voogt, E; Grzeschik, K H; Pearson, P L; Meera Khan, P

      1981-01-01

      The experiments reported in this paper indicate that the expression of human adenosine deaminase complexing protein (ADCP) in the human-rodent somatic cell hybrids is influenced by the state of confluency of the cells and the background rodent genome. Thus, the complement of the L-cell derived A9 or B82 mouse parent apparently prevents the expression of human ADCP in the interspecific somatic cell hybrids. In the a3, E36, or RAG hybrids the human ADCP expression was not prevented by the rodent genome and was found to be proportional to the degree of confluency of the cell in the culture as in the case of primary human fibroblasts. An analysis of human chromosomes, chromosome specific enzyme markers, and ADCP in a panel of rodent-human somatic cell hybrids optimally maintained and harvested at full confluency has shown that the expression of human ADCP in the mouse (RAG)-human as well as in the hamster (E36 or a3)-human hybrids is determined by a gene(s) in human chromosome 2 and that neither chromosome 6 nor any other of the chromosomes of man carry any gene(s) involved in the formation of human ADCP at least in the Chinese hamster-human hybrids. A series of rodent-human hybrid clones exhibiting a mitotic separation of IDH1 and MDH1 indicated that ADCP is most probably situated between corresponding loci in human chromosome 2.

    14. Effects of HZE irradiation on chemical neurotransmission in rodent hippocampus

      Science.gov (United States)

      Machida, Mayumi

      Space radiation represents a significant risk to the CNS (central nervous system) during space missions. Most harmful are the HZE (high mass, highly charged (Z), high energy) particles, e.g. 56Fe, which possess high ionizing ability, dense energy deposition pattern, and high penetrance. Accumulating evidence suggests that radiation has significant impact on cognitive functions. In ground-base experiments, HZE radiation induces pronounced deficits in hippocampus dependent learning and memory in rodents. However, the mechanisms underlying these impairments are mostly unknown. Exposure to HZE radiation elevates the level of oxidation, resulting in cell loss, tissue damage and functional deficits through direct ionization and generation of reactive oxygen species (ROS). When hippocampal slices were exposed to ROS, neuronal excitability was reduced. My preliminary results showed enhanced radio-vulnerability of the hippocampus and reduction in basal and depolarization-evoked [3H]-norepinephrine release after HZE exposure. These results raised the possibility that HZE radiation deteriorates cognitive function through radiation-induced impairments in hippocampal chemical neurotransmission, the hypothesis of this dissertation. In Aim 1 I have focused on the effects of HZE radiation on release of major neurotransmitter systems in the hippocampus. I have further extended my research on the levels of receptors of these systems in Aim 2. In Aim 3, I have studied the level of oxidation in membranes of my samples. My research reveals that HZE radiation significantly reduces hyperosmotic sucrose evoked [3H]-glutamate and [14C]-GABA release both three and six months post irradiation. The same radiation regimen also significantly enhances oxidative stress as indicated by increased levels of lipid peroxidation in the hippocampus, suggesting that increased levels of lipid peroxidation may play a role in reduction of neurotransmitter release. HZE radiation also significantly reduces

    15. A systematic review of discomfort due to toe or ear clipping in laboratory rodents

      Science.gov (United States)

      Geessink, Florentine J.; Brouwer, Michelle A. E.; Tillema, Alice; Ritskes-Hoitinga, Merel

      2017-01-01

      Toe clipping and ear clipping (also ear notching or ear punching) are frequently used methods for individual identification of laboratory rodents. These procedures potentially cause severe discomfort, which can reduce animal welfare and distort experimental results. However, no systematic summary of the evidence on this topic currently exists. We conducted a systematic review of the evidence for discomfort due to toe or ear clipping in rodents. The review methodology was pre-specified in a registered review protocol. The population, intervention, control, outcome (PICO) question was: In rodents, what is the effect of toe clipping or ear clipping, compared with no clipping or sham clipping, on welfare-related outcomes? Through a systematic search in PubMed, Embase, Web of Science and grey literature, we identified seven studies on the effect of ear clipping on animal welfare, and five such studies on toe clipping. Studies were included in the review if they contained original data from an in vivo experiment in rodents, assessing the effect of toe clipping or ear clipping on a welfare-related outcome. Case studies and studies applying unsuitable co-interventions were excluded. Study quality was appraised using an extended version of SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE)’s risk of bias tool for animal studies. Study characteristics and outcome measures were highly heterogeneous, and there was an unclear or high risk of bias in all studies. We therefore present a narrative synthesis of the evidence identified. None of the studies reported a sample size calculation. Out of over 60 different outcomes, we found evidence of discomfort due to ear clipping in the form of increased respiratory volume, vocalization and blood pressure. For toe clipping, increased vocalization and decreased motor activity in pups were found, as well as long-term effects in the form of reduced grip strength and swimming ability in adults. In conclusion, there

    16. Effect size and statistical power in the rodent fear conditioning literature - A systematic review.

      Science.gov (United States)

      Carneiro, Clarissa F D; Moulin, Thiago C; Macleod, Malcolm R; Amaral, Olavo B

      2018-01-01

      Proposals to increase research reproducibility frequently call for focusing on effect sizes instead of p values, as well as for increasing the statistical power of experiments. However, it is unclear to what extent these two concepts are indeed taken into account in basic biomedical science. To study this in a real-case scenario, we performed a systematic review of effect sizes and statistical power in studies on learning of rodent fear conditioning, a widely used behavioral task to evaluate memory. Our search criteria yielded 410 experiments comparing control and treated groups in 122 articles. Interventions had a mean effect size of 29.5%, and amnesia caused by memory-impairing interventions was nearly always partial. Mean statistical power to detect the average effect size observed in well-powered experiments with significant differences (37.2%) was 65%, and was lower among studies with non-significant results. Only one article reported a sample size calculation, and our estimated sample size to achieve 80% power considering typical effect sizes and variances (15 animals per group) was reached in only 12.2% of experiments. Actual effect sizes correlated with effect size inferences made by readers on the basis of textual descriptions of results only when findings were non-significant, and neither effect size nor power correlated with study quality indicators, number of citations or impact factor of the publishing journal. In summary, effect sizes and statistical power have a wide distribution in the rodent fear conditioning literature, but do not seem to have a large influence on how results are described or cited. Failure to take these concepts into consideration might limit attempts to improve reproducibility in this field of science.

    17. Effect size and statistical power in the rodent fear conditioning literature – A systematic review

      Science.gov (United States)

      Macleod, Malcolm R.

      2018-01-01

      Proposals to increase research reproducibility frequently call for focusing on effect sizes instead of p values, as well as for increasing the statistical power of experiments. However, it is unclear to what extent these two concepts are indeed taken into account in basic biomedical science. To study this in a real-case scenario, we performed a systematic review of effect sizes and statistical power in studies on learning of rodent fear conditioning, a widely used behavioral task to evaluate memory. Our search criteria yielded 410 experiments comparing control and treated groups in 122 articles. Interventions had a mean effect size of 29.5%, and amnesia caused by memory-impairing interventions was nearly always partial. Mean statistical power to detect the average effect size observed in well-powered experiments with significant differences (37.2%) was 65%, and was lower among studies with non-significant results. Only one article reported a sample size calculation, and our estimated sample size to achieve 80% power considering typical effect sizes and variances (15 animals per group) was reached in only 12.2% of experiments. Actual effect sizes correlated with effect size inferences made by readers on the basis of textual descriptions of results only when findings were non-significant, and neither effect size nor power correlated with study quality indicators, number of citations or impact factor of the publishing journal. In summary, effect sizes and statistical power have a wide distribution in the rodent fear conditioning literature, but do not seem to have a large influence on how results are described or cited. Failure to take these concepts into consideration might limit attempts to improve reproducibility in this field of science. PMID:29698451

    18. Of mice and women: rodent models of placental malaria

      DEFF Research Database (Denmark)

      Hviid, Lars; Marinho, Claudio R F; Staalsoe, Trine

      2010-01-01

      Pregnant women are at increased malaria risk. The infections are characterized by placental accumulation of infected erythrocytes (IEs) with adverse consequences for mother and baby. Placental IE sequestration in the intervillous space is mediated by variant surface antigens (VSAs) selectively...... expressed in placental malaria (PM) and specific for chondroitin sulfate A (CSA). In Plasmodium falciparum, these VSA(PM) appear largely synonymous with the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family variant VAR2CSA. As rodent malaria parasites do not possess PfEMP1 homologs......, the usefulness of experimental mouse PM models remains controversial. However, many features of murine and human PM are similar, including involvement of VSAs analogous to PfEMP1. It thus appears that rodent model studies can further the understanding of VSA-dependent malaria pathogenesis and immunity....

    19. Two new rodent models for actinide toxicity studies

      International Nuclear Information System (INIS)

      Taylor, G.N.; Jones, C.W.; Gardner, P.A.; Lloyd, R.D.; Mays, C.W.; Charrier, K.E.

      1981-01-01

      Two small rodent species, the grasshopper mouse (Onychomys leucogaster) and the deer mouse (Peromyscus maniculatus), have tenacious and high retention in the liver and skeleton of plutonium and americium following intraperitoneal injection of Pu and Am in citrate solution. Liver retention of Pu and Am in the grasshopper mouse is higher than liver retention in the deer mouse. Both of these rodents are relatively long-lived, breed well in captivity, and adapt suitably to laboratory conditions. It is suggested that these two species of mice, in which plutonium retention is high and prolonged in both the skeleton and liver, as it is in man, may be useful animal models for actinide toxicity studies

    20. Multiplex PCR identification of Taenia spp. in rodents and carnivores.

      Science.gov (United States)

      Al-Sabi, Mohammad N S; Kapel, Christian M O

      2011-11-01

      The genus Taenia includes several species of veterinary and public health importance, but diagnosis of the etiological agent in definitive and intermediate hosts often relies on labor intensive and few specific morphometric criteria, especially in immature worms and underdeveloped metacestodes. In the present study, a multiplex PCR, based on five primers targeting the 18S rDNA and ITS2 sequences, produced a species-specific banding patterns for a range of Taenia spp. Species typing by the multiplex PCR was compared to morphological identification and sequencing of cox1 and/or 12S rDNA genes. As compared to sequencing, the multiplex PCR identified 31 of 32 Taenia metacestodes from rodents, whereas only 14 cysts were specifically identified by morphology. Likewise, the multiplex PCR identified 108 of 130 adult worms, while only 57 were identified to species by morphology. The tested multiplex PCR system may potentially be used for studies of Taenia spp. transmitted between rodents and carnivores.

    1. A glimpse on the pattern of rodent diversification

      DEFF Research Database (Denmark)

      Fabre, Pierre-Henri Fréderic; Hautier, Lionel; Dimitrov, Dimitar Stefanov

      2012-01-01

      BACKGROUND:Development of phylogenetic methods that do not rely on fossils for the study of evolutionary processes through time have revolutionized the field of evolutionary biology and resulted in an unprecedented expansion of our knowledge about the tree of life. These methods have helped to shed...... molecular works. A relaxed molecular clock dating approach provided a time framework for speciation events. We found that the Myomorpha clade shows a greater degree of variation in diversification rates than Sciuroidea, Caviomorpha, Castorimorpha and Anomaluromorpha. We identified a number of shifts...... imbalances and the time line we discuss the potential role of different diversification factors that might have shaped the rodents radiation. CONCLUSIONS:The present glimpse on the diversification pattern of rodents can be used for further comparative meta-analyses. Muroid lineages have a greater degree...

    2. Short interspersed elements (SINEs) of the Geomyoidea superfamily rodents.

      Science.gov (United States)

      Gogolevsky, Konstantin P; Kramerov, Dmitri A

      2006-05-24

      A new short interspersed element (SINE) was isolated from the genome of desert kangaroo rat (Dipodomys deserti) using single-primer PCR. This SINE consists of two monomers: the left monomer (IDL) resembles rodent ID element and other tRNAAla(CGC)-derived SINEs, whereas the right one (Geo) shows no similarity with known SINE sequences. PCR and hybridization analyses demonstrated that IDL-Geo SINE is restricted to the rodent superfamily Geomyoidea (families Geomyidea and Heteromyidea). Isolation and analysis of IDL-Geo from California pocket mouse (Chaetodipus californicus) and Botta's pocket gopher (Thomomys bottae) revealed some species-specific features of this SINE family. The structure and evolution of known dimeric SINEs are discussed.

    3. Methods for Dissecting Motivation and Related Psychological Processes in Rodents.

      Science.gov (United States)

      Ward, Ryan D

      2016-01-01

      Motivational impairments are increasingly recognized as being critical to functional deficits and decreased quality of life in patients diagnosed with psychiatric disease. Accordingly, much preclinical research has focused on identifying psychological and neurobiological processes which underlie motivation . Inferring motivation from changes in overt behavioural responding in animal models, however, is complicated, and care must be taken to ensure that the observed change is accurately characterized as a change in motivation , and not due to some other, task-related process. This chapter discusses current methods for assessing motivation and related psychological processes in rodents. Using an example from work characterizing the motivational impairments in an animal model of the negative symptoms of schizophrenia, we highlight the importance of careful and rigorous experimental dissection of motivation and the related psychological processes when characterizing motivational deficits in rodent models . We suggest that such work is critical to the successful translation of preclinical findings to therapeutic benefits for patients.

    4. Citral reduces nociceptive and inflammatory response in rodents

      OpenAIRE

      Quintans-Júnior, Lucindo J.; Guimarães, Adriana G.; Santana, Marilia T. de; Araújo, Bruno E.S.; Moreira, Flávia V.; Bonjardim, Leonardo R.; Araújo, Adriano A. S.; Siqueira, Jullyana S.; Antoniolli, Ângelo R.; Botelho, Marco A.; Almeida, Jackson R. G. S.; Santos, Márcio R. V.

      2011-01-01

      Citral (CIT), which contains the chiral enantiomers, neral (cis) and geranial (trans), is the majority monoterpene from Lippia alba and Cymbopogon citratus. The present study aimed to evaluate CIT for antinociceptive and anti-inflammatory activities in rodents. Antinociceptive and anti-inflammatory effects were studied by measuring nociception through acetic acid and formalin tests, while inflammation was verified by inducing peritonitis and paw edema with carrageenan. All tested doses of CIT...

    5. The Need for Speed in Rodent Locomotion Analyses

      OpenAIRE

      Batka, Richard J.; Brown, Todd J.; Mcmillan, Kathryn P.; Meadows, Rena M.; Jones, Kathryn J.; Haulcomb, Melissa M.

      2014-01-01

      Locomotion analysis is now widely used across many animal species to understand the motor defects in disease, functional recovery following neural injury, and the effectiveness of various treatments. More recently, rodent locomotion analysis has become an increasingly popular method in a diverse range of research. Speed is an inseparable aspect of locomotion that is still not fully understood, and its effects are often not properly incorporated while analyzing data. In this hybrid manuscript,...

    6. Transformation of the rodent malaria parasite Plasmodium chabaudi

      OpenAIRE

      Spence, Philip J; Cunningham, Deirdre; Jarra, William; Lawton, Jennifer; Langhorne, Jean; Thompson, Joanne

      2011-01-01

      The rodent malaria parasite Plasmodium chabaudi chabaudi shares many features with human malaria species, including P. falciparum, and is the in vivo model of choice for many aspects of malaria research in the mammalian host, from sequestration of parasitized erythrocytes, to antigenic variation and host immunity and immunopathology. this protocol describes an optimized method for the transformation of mature blood-stage P.c. chabaudi and a description of a vector that targets efficient, sing...

    7. Role of rodents in transmission of Salmonella and Campylobacter

      OpenAIRE

      Meerburg, Dr BG; Kijlstra, Prof dr A

      2007-01-01

      Salmonella and Campylobacter are generally regarded as the most important food-borne pathogens in the world. Reduction or elimination of these pathogens in the first part of the food chain (on the farm) is important to prevent disease among consumers of animal products. In organic farming, elimination becomes more difficult, as food animals are allowed outdoors and have easy access to potential sources of hazardous pathogens. Whilst rodents are often associated by organic farmers with infr...

    8. Social memories in rodents: Methods, mechanisms and modulation by stress

      OpenAIRE

      van der Kooij MA; Sandi C.

      2011-01-01

      Intact social memory forms the basis of meaningful interactions between individuals. Many factors can modulate the quality of social memory, and these have been studied in detail in rodents. Social memory, however, cannot be considered a single entity. The term social memory reflects different processes, such as social recognition of a novel conspecific individual and social learning (or 'learning from others'). This review summarizes the findings obtained with behavioral paradigms that were ...

    9. Morphological evolution, ecological diversification and climate change in rodents

      OpenAIRE

      Renaud, Sabrina; Michaux, Jacques; Schmidt, Daniela N; Aguilar, Jean-Pierre; Mein, Pierre; Auffray, Jean-Christophe

      2005-01-01

      Among rodents, the lineage from Progonomys hispanicus to Stephanomys documents a case of increasing size and dental specialization during an approximately 9 Myr time-interval. On the contrary, some contemporaneous generalist lineages like Apodemus show a limited morphological evolution. Dental shape can be related to diet and can be used to assess the ecological changes along the lineages. Consequently, size and shape of the first upper molar were measured in order to quantify the patterns of...

    10. Performance Analysis of Exam Gloves Used for Aseptic Rodent Surgery

      Science.gov (United States)

      LeMoine, Dana M; Bergdall, Valerie K; Freed, Carrie

      2015-01-01

      Aseptic technique includes the use of sterile surgical gloves for survival surgeries in rodents to minimize the incidence of infections. Exam gloves are much less expensive than are surgical gloves and may represent a cost-effective, readily available option for use in rodent surgery. This study examined the effectiveness of surface disinfection of exam gloves with 70% isopropyl alcohol or a solution of hydrogen peroxide and peracetic acid (HP–PA) in reducing bacterial contamination. Performance levels for asepsis were met when gloves were negative for bacterial contamination after surface disinfection and sham ‘exertion’ activity. According to these criteria, 94% of HP–PA-disinfected gloves passed, compared with 47% of alcohol-disinfected gloves. In addition, the effect of autoclaving on the integrity of exam gloves was examined, given that autoclaving is another readily available option for aseptic preparation. Performance criteria for glove integrity after autoclaving consisted of: the ability to don the gloves followed by successful simulation of wound closure and completion of stretch tests without tearing or observable defects. Using this criteria, 98% of autoclaved nitrile exam gloves and 76% of autoclaved latex exam gloves met performance expectations compared with the performance of standard surgical gloves (88% nitrile, 100% latex). The results of this study support the use of HP–PA-disinfected latex and nitrile exam gloves or autoclaved nitrile exam gloves as viable cost-effective alternatives to sterile surgical gloves for rodent surgeries. PMID:26045458

    11. Isolating human DNA repair genes using rodent-cell mutants

      International Nuclear Information System (INIS)

      Thompson, L.H.; Weber, C.A.; Brookman, K.W.; Salazar, E.P.; Stewart, S.A.; Mitchell, D.L.

      1987-01-01

      The DNA repair systems of rodent and human cells appear to be at least as complex genetically as those in lower eukaryotes and bacteria. The use of mutant lines of rodent cells as a means of identifying human repair genes by functional complementation offers a new approach toward studying the role of repair in mutagenesis and carcinogenesis. In each of six cases examined using hybrid cells, specific human chromosomes have been identified that correct CHO cell mutations affecting repair of damage from uv or ionizing radiations. This finding suggests that both the repair genes and proteins may be virtually interchangeable between rodent and human cells. Using cosmid vectors, human repair genes that map to chromosome 19 have cloned as functional sequences: ERCC2 and XRCC1. ERCC1 was found to have homology with the yeast excision repair gene RAD10. Transformants of repair-deficient cell lines carrying the corresponding human gene show efficient correction of repair capacity by all criteria examined. 39 refs., 1 fig., 1 tab

    12. Performance analysis of exam gloves used for aseptic rodent surgery.

      Science.gov (United States)

      LeMoine, Dana M; Bergdall, Valerie K; Freed, Carrie

      2015-05-01

      Aseptic technique includes the use of sterile surgical gloves for survival surgeries in rodents to minimize the incidence of infections. Exam gloves are much less expensive than are surgical gloves and may represent a cost-effective, readily available option for use in rodent surgery. This study examined the effectiveness of surface disinfection of exam gloves with 70% isopropyl alcohol or a solution of hydrogen peroxide and peracetic acid (HP-PA) in reducing bacterial contamination. Performance levels for asepsis were met when gloves were negative for bacterial contamination after surface disinfection and sham 'exertion' activity. According to these criteria, 94% of HP-PA-disinfected gloves passed, compared with 47% of alcohol-disinfected gloves. In addition, the effect of autoclaving on the integrity of exam gloves was examined, given that autoclaving is another readily available option for aseptic preparation. Performance criteria for glove integrity after autoclaving consisted of: the ability to don the gloves followed by successful simulation of wound closure and completion of stretch tests without tearing or observable defects. Using this criteria, 98% of autoclaved nitrile exam gloves and 76% of autoclaved latex exam gloves met performance expectations compared with the performance of standard surgical gloves (88% nitrile, 100% latex). The results of this study support the use of HP-PA-disinfected latex and nitrile exam gloves or autoclaved nitrile exam gloves as viable cost-effective alternatives to sterile surgical gloves for rodent surgeries.

    13. Fire ignition during laser surgery in pet rodents

      Directory of Open Access Journals (Sweden)

      Collarile Tommaso

      2012-09-01

      Full Text Available Abstract Background Laser surgery is an attractive alternative to other means of section device in terms of tissue inflammation and interaction, which has been extensively used in human and veterinary medicine. Although accidental ignition during laser surgeries is sporadically reported in human medical literature, to the authors’ knowledge this is the first report regarding laser-dependent fire ignition during surgery in veterinary medicine. Case presentation Two rodents, a 13-month old, 27-gram, male pet mouse (Mus musculus and a 1-year old, female Russian hamster (Phodopus sungorus, underwent surgical removal of masses with diode laser. During the surgical procedures fires ignited from the face masks. The mouse presented severe burns on the head and both forelimbs, it was hospitalized and approximately 2 months after surgery burns were resolved. The hamster presented severe burns on the face and the proximal regions of the body. At 72 hours from the accident the hamster was euthanized. Conclusion The present report suggests that fire ignition is a potential life-threatening complication of laser surgery in non-intubated rodents maintained under volatile anesthesia. High oxygen concentrations, the presence of combustible, and the narrowness of the surgical field with the face mask during laser surgery on rodents are risk factors for fire ignition.

    14. Two New Mylagaulid Rodents from the Early Miocene of China.

      Directory of Open Access Journals (Sweden)

      Xiaoyu Lu

      Full Text Available Mylagaulid fossorial rodents are a common component of North American Miocene fossil faunas. However outside of North America, only three species are known from Asia. Here we report two new mylagaulids, Irtyshogaulus minor gen. et sp. nov. and Irtyshogaulus major gen. et sp. nov., recovered from early Miocene sediments in the Junggar Basin in northwestern China. The two new taxa are small-sized, high-crowned promylagauline rodents. Their lower molars possess high metastylid crests, small mesostylids, broad and posterolingually expanded labial inflections, and transversely extending metalophid IIs. The mesoconid is absent in both species. The anterior and posterior fossettids are large and equally developed. Their upper M1-2s possess a square occlusal surface with five deep fossettes. The two new taxa are distinguished from each other mainly by their size, the morphology of fossettes and fossettids, development of mesial and distal lophs, posterior reduction of M3, and the orientation of m2 hypolophid. Our phylogenetic analysis indicates that Irtyshogaulus and Lamugaulus (another early Miocene Asian mylagaulid are sister taxa. The two genera are nested among the North American promylagaulines, and share a common ancestor from North America, indicating early Miocene intercontinental dispersal within this clade of rodents.

    15. The valproic acid-induced rodent model of autism.

      Science.gov (United States)

      Nicolini, Chiara; Fahnestock, Margaret

      2018-01-01

      Autism is a lifelong neurodevelopmental disorder characterized by impairments in social communication and interaction and by repetitive patterns of behavior, interests and activities. While autism has a strong genetic component, environmental factors including toxins, pesticides, infection and drugs are known to confer autism susceptibility, likely by inducing epigenetic changes. In particular, exposure to valproic acid (VPA) during pregnancy has been demonstrated to increase the risk of autism in children. Furthermore, rodents prenatally exposed to this drug display behavioral phenotypes characteristics of the human condition. Indeed, in utero exposure of rodents to VPA represents a robust model of autism exhibiting face, construct and predictive validity. This model might better represent the many cases of idiopathic autism which are of environmental/epigenetic origins than do transgenic models carrying mutations in single autism-associated genes. The VPA model provides a valuable tool to investigate the neurobiology underlying autistic behavior and to screen for novel therapeutics. Here we review the VPA-induced rodent model of autism, highlighting its importance and reliability as an environmentally-induced animal model of autism. Copyright © 2017 Elsevier Inc. All rights reserved.

    16. Capacidad predictiva de la evaluación de los pares y focos del modelo de acreditación institucional en Chile Predictive capacity of peer evaluation and the focus of the institutional accreditation model in Chile

      Directory of Open Access Journals (Sweden)

      Emilio Rodríguez-Ponce

      2010-01-01

      Full Text Available El presente artículo presenta los resultados de un estudio sobre los procesos de acreditación institucional realizados en Chile en el periodo 2003-2006. El propósito del estudio es estimar la capacidad predictiva que la evaluación externa realizada por los comités de pares tuvo sobre los resultados finales de acreditación institucional. Para ello, se generó un modelo de regresión, donde las calificaciones de los pares evaluadores - sobre las áreas de acreditación 'Gestión Institucional'y 'Docencia de Pregrado' - se ingresaron como variable independiente y los resultados de acreditación, expresados en la decisión de acreditación y los años de vigencia, como variable dependiente. Como resultados, se comprobó que existe consistencia entre las etapas de evaluación externa y de decisión de acreditación; que las calificaciones otorgadas por los pares en el área de 'Docencia de Pregrado' tienen mayor capacidad predictiva que aquellas otorgadas en el área de 'Gestión Institucional', y, por último; que hay elementos para plantear que el foco de 'evaluación' (en comparación al foco de 'auditoria' fue predominante en el modelo de acreditación institucional chileno entre los años estudiados.This article presents the results of a study of the institutional accreditation processes that took place in Chile during the period of 2003 to 2006. The purpose of the study is to estimate the capacity of peer evaluation to predict the final results of institutional accreditation. Thus, a regression model was developed, in which the score given by the academic peers to the institutions -in the accreditation areas of 'Institutional Management' and 'Undergraduate Teaching Process' - were entered as the independent variable, and the accreditation results, expressed in the accreditation decision and the period of accreditation, were included in the model as the dependent variable. The results show that there is consistency between the peer

    17. Probabilistic Learning by Rodent Grid Cells.

      Science.gov (United States)

      Cheung, Allen

      2016-10-01

      Mounting evidence shows mammalian brains are probabilistic computers, but the specific cells involved remain elusive. Parallel research suggests that grid cells of the mammalian hippocampal formation are fundamental to spatial cognition but their diverse response properties still defy explanation. No plausible model exists which explains stable grids in darkness for twenty minutes or longer, despite being one of the first results ever published on grid cells. Similarly, no current explanation can tie together grid fragmentation and grid rescaling, which show very different forms of flexibility in grid responses when the environment is varied. Other properties such as attractor dynamics and grid anisotropy seem to be at odds with one another unless additional properties are assumed such as a varying velocity gain. Modelling efforts have largely ignored the breadth of response patterns, while also failing to account for the disastrous effects of sensory noise during spatial learning and recall, especially in darkness. Here, published electrophysiological evidence from a range of experiments are reinterpreted using a novel probabilistic learning model, which shows that grid cell responses are accurately predicted by a probabilistic learning process. Diverse response properties of probabilistic grid cells are statistically indistinguishable from rat grid cells across key manipulations. A simple coherent set of probabilistic computations explains stable grid fields in darkness, partial grid rescaling in resized arenas, low-dimensional attractor grid cell dynamics, and grid fragmentation in hairpin mazes. The same computations also reconcile oscillatory dynamics at the single cell level with attractor dynamics at the cell ensemble level. Additionally, a clear functional role for boundary cells is proposed for spatial learning. These findings provide a parsimonious and unified explanation of grid cell function, and implicate grid cells as an accessible neuronal population

    18. GeneLab: Multi-Omics Investigation of Rodent Research-1 Bio-Banked Tissues

      Science.gov (United States)

      Lai, San-Huei; Boyko, Valery; Chakravarty, Kaushik; Chen, Rick; Dueck, Sandra; Berrios, Daniel C.; Fogle, Homer; Marcu, Oana; Timucin, Linda; Reinsch, Sigrid; hide

      2016-01-01

      NASAs Rodent Research (RR) project is playing a critical role in advancing biomedical research on the physiological effects of space environments. Due to the limited resources for conducting biological experiments aboard the International Space Station (ISS), it is imperative to use crew time efficiently while maximizing high-quality science return. NASAs GeneLab project has as its primary objectives to 1) further increase the value of these experiments using a multi-omics, systems biology-based approach, and 2) disseminate these data without restrictions to the scientific community. The current investigation assessed viability of RNA, DNA, and protein extracted from archived RR-1 tissue samples for epigenomic, transcriptomic, and proteomic assays. During the first RR spaceflight experiment, a variety of tissue types were harvested from subjects, snap-frozen or RNAlater-preserved, and then stored at least a year at -80OC after return to Earth. They were then prioritized for this investigation based on likelihood of significant scientific value for spaceflight research. All tissues were made available to GeneLab through the bio-specimen sharing program managed by the Ames Life Science Data Archive and included mouse adrenal glands, quadriceps, gastrocnemius, tibialis anterior, extensor digitorum longus, soleus, eye, and kidney. We report here protocols for and results of these tissue extractions, and thus, the feasibility and value of these kinds of omics analyses. In addition to providing additional opportunities for investigation of spaceflight effects on the mouse transcriptome and proteome in new kinds of tissues, our results may also be of value to program managers for the prioritization of ISS crew time for rodent research activities. Support from the NASA Space Life and Physical Sciences Division and the International Space Station Program is gratefully acknowledged.

    19. Phobos: A novel software for recording rodents' behavior during the thigmotaxis and the elevated plus-maze test.

      Science.gov (United States)

      Telonis, Aristeidis G; Margarity, Marigoula

      2015-07-10

      Evaluation of fear and anxiety levels offers valuable insight on the impact of experimental conditions. The elevated plus-maze and the open field (thigmotactic responce) tests are two well-established behavioral procedures for the quantification of anxiety in rodents. In this study, Phobos, a novel, effective and simple application developed for recording rodents' behavior during the elevated plus-maze and the open-field test, is being presented. Phobos is able to generate all basic locomotor-related behavioral results at once, immediately after a simple manual record of the rodent's position, along with simultaneous analysis of the experiment in 5-min periods. The efficiency of Phobos is demonstrated by presenting results from the two behavioral tests showing that animal's behavior unfolds differently in each one. Phobos manages to ease the experimenter from laborious work by providing self-explanatory characteristics and a convenient way to record the behavior of the animal, while it quickly calculates all basic locomotor-related parameters, easing behavioral studies. Phobos is freely accessible at https://sourceforge.net/projects/phobosapplication/. Copyright © 2015. Published by Elsevier Ireland Ltd.

    20. Wild rodents as a model to discover genes and pathways underlying natural variation in infectious disease susceptibility.

      Science.gov (United States)

      Turner, A K; Paterson, S

      2013-11-01

      Individuals vary in their susceptibility to infectious disease, and it is now well established that host genetic factors form a major component of this variation. The discovery of genes underlying susceptibility has the potential to lead to improved disease control, through the identification and management of vulnerable individuals and the discovery of novel therapeutic targets. Laboratory rodents have proved invaluable for ascertaining the function of genes involved in immunity to infection. However, these captive animals experience conditions very different to the natural environment, lacking the genetic diversity and environmental pressures characteristic of natural populations, including those of humans. It has therefore often proved difficult to translate basic laboratory research to the real world. In order to further our understanding of the genetic basis of infectious disease resistance, and the evolutionary forces that drive variation in susceptibility, we propose that genetic research traditionally conducted on laboratory animals is expanded to the more ecologically valid arena of natural populations. In this article, we highlight the potential of using wild rodents as a new resource for biomedical research, to link the functional genetic knowledge gained from laboratory rodents with the variation in infectious disease susceptibility observed in humans and other natural populations. © 2013 John Wiley & Sons Ltd.

    1. Forest rodents provide directed dispersal of Jeffrey pine seeds

      Science.gov (United States)

      Briggs, J.S.; Wall, S.B.V.; Jenkins, S.H.

      2009-01-01

      Some species of animals provide directed dispersal of plant seeds by transporting them nonrandomly to microsites where their chances of producing healthy seedlings are enhanced. We investigated whether this mutualistic interaction occurs between granivorous rodents and Jeffrey pine (Pinus jeffreyi) in the eastern Sierra Nevada by comparing the effectiveness of random abiotic seed dispersal with the dispersal performed by four species of rodents: deer mice (Peromyscus maniculatus), yellow-pine and long-eared chipmunks (Tamias amoenus and T. quadrimaculatus), and golden-mantled ground squirrels (Spermophilus lateralis). We conducted two caching studies using radio-labeled seeds, the first with individual animals in field enclosures and the second with a community of rodents in open forest. We used artificial caches to compare the fates of seeds placed at the range of microsites and depths used by animals with the fates of seeds dispersed abiotically. Finally, we examined the distribution and survival of naturally establishing seedlings over an eight-year period.Several lines of evidence suggested that this community of rodents provided directed dispersal. Animals preferred to cache seeds in microsites that were favorable for emergence or survival of seedlings and avoided caching in microsites in which seedlings fared worst. Seeds buried at depths typical of animal caches (5–25 mm) produced at least five times more seedlings than did seeds on the forest floor. The four species of rodents differed in the quality of dispersal they provided. Small, shallow caches made by deer mice most resembled seeds dispersed by abiotic processes, whereas many of the large caches made by ground squirrels were buried too deeply for successful emergence of seedlings. Chipmunks made the greatest number of caches within the range of depths and microsites favorable for establishment of pine seedlings. Directed dispersal is an important element of the population dynamics of Jeffrey pine, a

    2. A Field Study of Plague and Tularemia in Rodents, Western Iran.

      Science.gov (United States)

      Mostafavi, Ehsan; Shahraki, Abdolrazagh Hashemi; Japoni-Nejad, Alireza; Esmaeili, Saber; Darvish, Jamshid; Sedaghat, Mohammad Mehdi; Mohammadi, Ali; Mohammadi, Zeinolabedin; Mahmoudi, Ahmad; Pourhossein, Behzad; Ghasemi, Ahmad; Gyuranecz, Miklós; Carniel, Elisabeth

      2017-04-01

      Kurdistan Province in Iran is a historical focus for plague and tularemia. This study aimed at assessing the current status of these two foci by studying their rodent reservoirs. Rodents were trapped and their ectoparasites were collected. The genus and species of both rodents and ectoparasites were determined. Serological analyses of rodent blood samples were done by enzyme-linked immunosorbent assay for plague and by standard tube agglutination assay for tularemia. Rodent spleen samples were subjected to bacterial culture, microscopic examination, and real-time PCR to search for active plague or tularemia infection. During this study, 245 rodents were trapped, of which the most abundant genera were Apodemus (40%), Mus (24.49%), and Meriones (12.65%). One hundred fifty-three fleas, 37 mites, and 54 ticks were collected on these rodents. The results of all direct and indirect tests were negative for plague. Serological tests were positive for tularemia in 4.8% of trapped rodents. This study is the first report on the presence of tularemia infection in rodents in Western Iran. Since Meriones persicus is a known reservoir for plague and tularemia, and this rodent carried plague and tularemia vectors in Marivan and Sanandaj districts, there is a real potential for the occurrence of these two diseases in this region.

    3. A pH and solvent optimized reverse-phase ion-paring-LC–MS/MS method that leverages multiple scan-types for targeted absolute quantification of intracellular metabolites

      DEFF Research Database (Denmark)

      McCloskey, Douglas; Gangoiti, Jon A.; Palsson, Bernhard O.

      2015-01-01

      Comprehensive knowledge of intracellular biochemistry is needed to accurately understand, model, and manipulate metabolism for industrial and therapeutic applications. Quantitative metabolomics has been driven by advances in analytical instrumentation and can add valuable knowledge to the underst......Comprehensive knowledge of intracellular biochemistry is needed to accurately understand, model, and manipulate metabolism for industrial and therapeutic applications. Quantitative metabolomics has been driven by advances in analytical instrumentation and can add valuable knowledge...... existing reverse phase ion-paring liquid chromatography methods for separation and detection of polar and anionic compounds that comprise key nodes of intracellular metabolism by optimizing pH and solvent composition. In addition, the presented method utilizes multiple scan types provided by hybrid...

    4. O MERCADO ACADÊMICO CONTÁBIL BRASILEIRO: UMA ANÁLISE DO CENÁRIO A PARTIR DAS PRÁTICAS DE PUBLICAÇÃO E AVALIAÇÃO POR PARES

      OpenAIRE

      Espejo, Márcia Maria Santos Bortolocci; Azavedo, Sayuri Unoki; Trombelli, Renata Oliveira; Voese, Simone Bernardes

      2013-01-01

      O estudo tem como objetivo analisar o cenário acadêmico contábil brasileiro no que se refere às práticas de publicação e avaliação por pares, refletindo especificamente sobre como os eventos podem contribuir efetivamente para a eficiência do processo de qualificação da produção científica da área de Contabilidade, por meio da elaboração de uma proposta para a comunidade acadêmica. Esta pesquisa possui abordagem quantitativa e emerge a partir de três construtos: a conversão das publicações, a ...

    5. Evaluation of STD/HIV/AIDS peer-education and danger: a local perspective Avaliação de educação das DST/HIV/aids pelos pares e perigo: suma perspectiva local

      Directory of Open Access Journals (Sweden)

      Hélène Laperrière

      2008-12-01

      Full Text Available An evaluation of peer-education projects with sex workers, men who have sex with men and marginalized adolescents, was introduced in a remote region of Brazil. The context of varied limits of predictability made it difficult to conduct inquiry. To go beyond available epidemiological surveys and questionnaires on sexual behavior, a self-evaluation aimed at increasing pragmatic knowledge about prevention in a challenging socio-political context. During five-months, a participatory-action research explored participant observation; individual and collective exchanges with users, peer-educators, coordinators, administrators, politicians and regional health professionals. Collective understanding of peer-education in prostitution zones underlines the reality of unforeseen social repercussions and confluence/divergence of multiple actors' perspectives. It identifies meaningful dimensions at a community-level, such as the collective history and dangerous working conditions. Nurses face complex struggles and negotiations over multiple actors in their practice. This study suggests that nurses have a role to play in the conceptualization of participatory evaluation. It also underlines the threats to their physical and social safety, which they might share with peer-educators.Uma avaliação dos projetos de educação por pares com trabalhadores do sexo, homens que fazem sexo com homens e adolescentes marginalizados foi implantada numa região do interior do Brasil. Os diversos limites postos à previsibilidade tornaram difícil conduzir a investigação. Indo além das pesquisas epidemiológicas e questionários evolutivos sobre os comportamentos sexuais, esta auto-avaliação enfatiza o desenvolvimento de conhecimento pragmático sobre prevenção em um contexto sociopolítico desafiante. Durante cinco meses, uma pesquisa-ação explorou observação participante, entrevistas individuais e coletivas junto com usuários, pares educadores, coordenadores

    6. OXIDACIÓN POR VÍA HÚMEDA CATALÍTICA DE EFLUENTES INDUSTRIALES EMPLEANDO UN CATALIZADOR DE Pt SOPORTADO EN NANOTUBOS DE CARBONO DE PARED MÚLTIPLE

      Directory of Open Access Journals (Sweden)

      Gabriel Ovejero

      2011-01-01

      Full Text Available En el presente trabajo se ha estudiado la efectividad de la oxidación por vía húmeda catalítica para tratar aguas residuales industriales en un reactor por lote. Para ello se han realizado ensayos con un contaminante modelo, el colorante básico Amarillo Directo 11 empleando como catalizador platino soportado en nanotubos de carbono de pared múltiple (Pt/MWNT. Así mismo se ha realizado el tratamiento de dos efluentes industriales. Los resultados muestran tanto la alta efectividad del tratamiento en presencia del catalizador, como una importante disminución del carbono orgánico total y de la toxicidad en el efluente final. Se concluye que el proceso se ha demostrado eficaz tanto para el tratamiento del colorante básico ensayado, como en los dos efluentes residuales industriales.

    7. REDES SOCIALES Y EFECTO DE LOS PARES COMO PREDICTORES DEL RENDIMIENTO ESCOLAR EN ALUMNOS DE CUARTO AÑO BÁSICO DE LA COMUNA DE CONCEPCIÓN

      Directory of Open Access Journals (Sweden)

      Valentín Vergara

      2009-01-01

      Full Text Available Esta investigación parte desde la problemática existente en investigación educacional y sus cercanías teóricas con elementos de la teoría de redes sociales. A partir de los conceptos de efecto pares y de cohesión de la red se intenta buscar un modelo que explique de manera óptima el rendimiento en alumnos de cuarto año básico en la prueba SIMCE de matemática en la comuna de Concepción. Se trabajó con una muestra no probabilística e intencionada compuesta de 435 alumnos pertenecientes a 12 cursos de siete escuelas, donde se aplicó un instrumento para medir la cohesión de las redes sociales y luego se comparó con datos obtenidos a partir de la base de datos SIMCE para el año 2006. Los resultados indican que el modelo óptimo explica un 63,04% de la variación de puntajes de la prueba de matemática. Las variables que componen este modelo son efecto fijo de la escuela; efecto pares; cohesión de la red; y educación de las madres. Como conclusión, se demuestra la consistencia de los resultados con lo que sugiere la teoría, además de dejar abiertas preguntas sobre el efecto de las escuelas que pueden ser abordadas en investigaciones futuras.

    8. Neuroanatomical Substrates of Rodent Social Behavior: The Medial Prefrontal Cortex and Its Projection Patterns

      Science.gov (United States)

      Ko, Jaewon

      2017-01-01

      Social behavior encompasses a number of distinctive and complex constructs that form the core elements of human imitative culture, mainly represented as either affiliative or antagonistic interactions with conspecifics. Traditionally considered in the realm of psychology, social behavior research has benefited from recent advancements in neuroscience that have accelerated identification of the neural systems, circuits, causative genes and molecular mechanisms that underlie distinct social cognitive traits. In this review article, I summarize recent findings regarding the neuroanatomical substrates of key social behaviors, focusing on results from experiments conducted in rodent models. In particular, I will review the role of the medial prefrontal cortex (mPFC) and downstream subcortical structures in controlling social behavior, and discuss pertinent future research perspectives. PMID:28659766

    9. Intraoperative laser speckle contrast imaging improves the stability of rodent middle cerebral artery occlusion model

      Science.gov (United States)

      Yuan, Lu; Li, Yao; Li, Hangdao; Lu, Hongyang; Tong, Shanbao

      2015-09-01

      Rodent middle cerebral artery occlusion (MCAO) model is commonly used in stroke research. Creating a stable infarct volume has always been challenging for technicians due to the variances of animal anatomy and surgical operations. The depth of filament suture advancement strongly influences the infarct volume as well. We investigated the cerebral blood flow (CBF) changes in the affected cortex using laser speckle contrast imaging when advancing suture during MCAO surgery. The relative CBF drop area (CBF50, i.e., the percentage area with CBF less than 50% of the baseline) showed an increase from 20.9% to 69.1% when the insertion depth increased from 1.6 to 1.8 cm. Using the real-time CBF50 marker to guide suture insertion during the surgery, our animal experiments showed that intraoperative CBF-guided surgery could significantly improve the stability of MCAO with a more consistent infarct volume and less mortality.

    10. Percepção dos estudantes universitários sobre o consumo de drogas entre seus pares no ABC Paulista, São Paulo, Brasil Percepciones de los estudiantes universitarios sobre el consumo de drogas entre sus pares en el ABC Paulista, en Sao Paulo, Brasil University students' perception regarding drug use among peers in the ABC Region of São Paulo, Brazil

      Directory of Open Access Journals (Sweden)

      Hercilio Pereira de Oliveira Júnior

      2009-01-01

      Full Text Available O objetivo deste estudo foi analisar a relação entre o uso de drogas e as normas percebidas pelos estudantes universitários entre seus pares. Trata-se de estudo transversal, baseado em um censo. Foram avaliados todos os estudantes dos 2 e 3 anos dos cursos de medicina e enfermagem. O projeto incluiu estudantes entre 18 e 24 anos da Faculdade de Medicina do ABC, em Santo André, Brasil. Os estudantes foram convidados a, voluntariamente, responder um questionário que avalia, entre outras variáveis, consumo próprio de drogas e percepção sobre o uso dos pares. Houve participação de 274 estudantes. A fim de analizar os dados, foi utilizado o pacote SPSS e técnicas descritivas, incluindo-se frequências e médias. Houve superestimativa da percepção do consumo de drogas em relação à frequência descrita de uso próprio pelos estudantes.El objetivo de este estudio fue analizar la relación entre el uso de drogas y las normas percibidas entre estudiantes universitarios. La muestra fue de tipo transversal, basada en una encuesta. El estudio evaluó a los estudiantes universitarios de los cursos de enfermería y de medicina de la Facultad de Medicina de la zona del ABC, en Santo André, en Brasil. Los estudiantes fueron invitados a participar respondiendo a un cuestionario que permitió evaluar su propio uso de drogas y el consumo percibido de las drogas entre sus pares. Participaron 274 entrevistados, con edad entre 18 y 24 años. Para presentar los resultados se usaron procedimientos descriptivos; para analizar los datos se usó el paquete estadístico SPSS. Se encontró que los estudiantes sobrestimaron la percepción de la norma de consumo entre sus pares.This study aimed to analyze the relation between university students' perceived norms and actual drug use among their peers. This cross-sectional study was based on a survey. Evaluations involved all second- and third-year students (ages between 18 and 24 years of the nursing and

    11. Using the Activity-based Anorexia Rodent Model to Study the Neurobiological Basis of Anorexia Nervosa.

      Science.gov (United States)

      Chowdhury, Tara Gunkali; Chen, Yi-Wen; Aoki, Chiye

      2015-10-22

      Anorexia nervosa (AN) is a psychiatric illness characterized by excessively restricted caloric intake and abnormally high levels of physical activity. A challenging illness to treat, due to the lack of understanding of the underlying neurobiology, AN has the highest mortality rate among psychiatric illnesses. To address this need, neuroscientists are using an animal model to study how neural circuits may contribute toward vulnerability to AN and may be affected by AN. Activity-based anorexia (ABA) is a bio-behavioral phenomenon described in rodents that models the key symptoms of anorexia nervosa. When rodents with free access to voluntary exercise on a running wheel experience food restriction, they become hyperactive - running more than animals with free access to food. Here, we describe the procedures by which ABA is induced in adolescent female C57BL/6 mice. On postnatal day 36 (P36), the animal is housed with access to voluntary exercise on a running wheel. After 4 days of acclimation to the running wheel, on P40, all food is removed from the cage. For the next 3 days, food is returned to the cage (allowing animals free food access) for 2 hr daily. After the fourth day of food restriction, free access to food is returned and the running wheel is removed from the cage to allow the animals to recover. Continuous multi-day analysis of running wheel activity shows that mice become hyperactive within 24 hr following the onset of food restriction. The mice run even during the limited time during which they have access to food. Additionally, the circadian pattern of wheel running becomes disrupted by the experience of food restriction. We have been able to correlate neurobiological changes with various aspects of the animals' wheel running behavior to implicate particular brain regions and neurochemical changes with resilience and vulnerability to food-restriction induced hyperactivity.

    12. Effect of woodland patch size on rodent seed predation in a fragmented landscape

      Directory of Open Access Journals (Sweden)

      J. Loman

      2007-05-01

      Full Text Available Predation on large woody plant seeds; chestnuts, acorns and sloe kernels, was studied in deciduous forests of two size classes: small woodlots (<1 ha and large woods (at least 25 ha in southern Sweden. Seeds used for the study were artificially distributed on the forest ground and seed predation measured as seed removal. Predation rate was similar in both types of woods. However, rodent density was higher in small woodlots and a correction for differences in rodent density showed that predation rate per individual rodent was higher in the large woods. This suggests that the small woodlots (including the border zone and their adjacent fields have more rodent food per area unit. A small woodlot cannot be considered a representative sample of a large continuous forest, even if the habitats appear similar. There was a strong effect of rodent density on seed predation rate. This suggests that rodents are major seed predators in this habitat.

    13. Helminth Infections of Rodents and Their Zoonotic Importance in Boyer-Ahmad District, Southwestern Iran

      OpenAIRE

      RANJBAR, Mohammad Javad; SARKARI, Bahador; MOWLAVI, Gholam Reza; SEIFOLLAHI, Zeinab; MOSHFE, Abdolali; ABDOLAHI KHABISI, Samaneh; MOBEDI, Iraj

      2017-01-01

      AbstractBackground: Rodents are considered as reservoirs of various zoonotic diseases including helminthic infections. The current study aimed to evaluate the prevalence of helminth infections in rodents, in Boyer-Ahmad district, Southwestern Iran.Methods: Overall, 52 rodents were captured from various areas of the district by Sherman live traps. The animals were then euthanized and dissected. During necropsy, each organ was examined macroscopically for presence of any cyst or visible parasit...

    14. Research Note. Occurrence of gastrointestinal helminths in commensal rodents from Tabasco, Mexico

      OpenAIRE

      Cigarroa-Toledo N.; Santos-Martinez Y. De Los; Zaragoza-Vera C. V.; Garcia-Rodriguez M. M.; Baak-Baak C. M.; Machain-Williams C.; Garcia-Rejon J. E.; Panti-May J. A.; Torres-Chable O. M.

      2017-01-01

      The aim of this study was to determine the prevalence and species composition of helminths in commensal rodents captured inside private residences in the city of Villahermosa in Tabasco, Mexico. Trapping was performed at each house for three consecutive nights from October to December 2015. Fifty commensal rodents were captured: 23 Rattus norvegicus, 16 Mus musculus and 11 Rattus rattus. Rodents were transported alive to the laboratory and held in cages until they defecated. Feces were analyz...

    15. Tularemia and plague survey in rodents in an earthquake zone in southeastern Iran

      Science.gov (United States)

      Gyuranecz, Miklós

      2015-01-01

      OBJECTIVES: Earthquakes are one the most common natural disasters that lead to increased mortality and morbidity from transmissible diseases, partially because the rodents displaced by an earthquake can lead to an increased rate of disease transmission. The aim of this study was to evaluate the prevalence of plague and tularemia in rodents in the earthquake zones in southeastern Iran. METHODS: In April 2013, a research team was dispatched to explore the possible presence of diseases in rodents displaced by a recent earthquake magnitude 7.7 around the cities of Khash and Saravan in Sistan and Baluchestan Province. Rodents were trapped near and in the earthquake zone, in a location where an outbreak of tularemia was reported in 2007. Rodent serums were tested for a serological survey using an enzyme-linked immunosorbent assay. RESULTS: In the 13 areas that were studied, nine rodents were caught over a total of 200 trap-days. Forty-eight fleas and 10 ticks were obtained from the rodents. The ticks were from the Hyalomma genus and the fleas were from the Xenopsylla genus. All the trapped rodents were Tatera indica. Serological results were negative for plague, but the serum agglutination test was positive for tularemia in one of the rodents. Tatera indica has never been previously documented to be involved in the transmission of tularemia. CONCLUSIONS: No evidence of the plague cycle was found in the rodents of the area, but evidence was found of tularemia infection in rodents, as demonstrated by a positive serological test for tularemia in one rodent. PMID:26602769

    16. [11 C]Rhodamine-123: Synthesis and biodistribution in rodents

      International Nuclear Information System (INIS)

      Bao Xiaofeng; Lu Shuiyu; Liow, Jeih-San; Morse, Cheryl L.; Anderson, Kacey B.; Zoghbi, Sami S.; Innis, Robert B.; Pike, Victor W.

      2012-01-01

      Introduction: Rhodamine-123 is a known substrate for the efflux transporter, P-glycoprotein (P-gp). We wished to assess whether rhodamine-123 might serve as a useful substrate for developing probes for imaging efflux transporters in vivo with positron emission tomography (PET). For this purpose, we aimed to label rhodamine-123 with carbon-11 (t 1/2 = 20.4 min) and to study its biodistribution in rodents. Methods: [ 11 C]Rhodamine-123 was prepared by treating rhodamine-110 (desmethyl-rhodamine-123) with [ 11 C]methyl iodide. The biodistribution of this radiotracer was studied with PET in wild-type mice and rats, in efflux transporter knockout mice, in wild-type rats pretreated with DCPQ (an inhibitor of P-gp) or with cimetidine (an inhibitor of organic cation transporters; OCT), and in P-gp knockout mice pretreated with cimetidine. Unchanged radiotracer in forebrain, plasma and peripheral tissues was also measured ex vivo at 30 min after radiotracer administration to wild-type and efflux transporter knockout rodents. Results: [ 11 C]Rhodamine-123 was obtained in 4.4% decay-corrected radiochemical yield from cyclotron-produced [ 11 C]carbon dioxide. After intravenous administration of [ 11 C]rhodamine-123 to wild-type rodents, PET and ex vivo measurements showed radioactivity uptake was very low in brain, but relatively high in some other organs such as heart, and especially liver and kidney. Inhibition of P-gp increased uptake in brain, heart, kidney and liver, but only by up to twofold. Secretion of radioactivity from kidney was markedly reduced by OCT knockout or pretreatment with cimetidine. Conclusions: [ 11 C]Rhodamine-123 was unpromising as a PET probe for P-gp function and appears to be a strong substrate of OCT in kidney. Cimetidine appears effective for blocking OCT in kidney in vivo.

    17. Default-mode-like network activation in awake rodents.

      Directory of Open Access Journals (Sweden)

      Jaymin Upadhyay

      Full Text Available During wakefulness and in absence of performing tasks or sensory processing, the default-mode network (DMN, an intrinsic central nervous system (CNS network, is in an active state. Non-human primate and human CNS imaging studies have identified the DMN in these two species. Clinical imaging studies have shown that the pattern of activity within the DMN is often modulated in various disease states (e.g., Alzheimer's, schizophrenia or chronic pain. However, whether the DMN exists in awake rodents has not been characterized. The current data provides evidence that awake rodents also possess 'DMN-like' functional connectivity, but only subsequent to habituation to what is initially a novel magnetic resonance imaging (MRI environment as well as physical restraint. Specifically, the habituation process spanned across four separate scanning sessions (Day 2, 4, 6 and 8. At Day 8, significant (p<0.05 functional connectivity was observed amongst structures such as the anterior cingulate (seed region, retrosplenial, parietal, and hippocampal cortices. Prior to habituation (Day 2, functional connectivity was only detected (p<0.05 amongst CNS structures known to mediate anxiety (i.e., anterior cingulate (seed region, posterior hypothalamic area, amygdala and parabracial nucleus. In relating functional connectivity between cingulate-default-mode and cingulate-anxiety structures across Days 2-8, a significant inverse relationship (r = -0.65, p = 0.0004 was observed between these two functional interactions such that increased cingulate-DMN connectivity corresponded to decreased cingulate anxiety network connectivity. This investigation demonstrates that the cingulate is an important component of both the rodent DMN-like and anxiety networks.

    18. Sex differences in chronic stress effects on cognition in rodents.

      Science.gov (United States)

      Luine, Victoria; Gomez, Juan; Beck, Kevin; Bowman, Rachel

      2017-01-01

      Chronic stress causes deleterious changes in physiological function in systems ranging from neural cells in culture to laboratory rodents, sub-human primates and humans. It is notable, however, that the vast majority of research in this area has been conducted in males. In this review, we provide information about chronic stress effects on cognition in female rodents and contrast it with responses in male rodents. In general, females show cognitive resilience to chronic stressors which impair male cognitive function using spatial tasks including the radial arm maze, radial arm water maze, Morris water maze, Y-maze and object placement. Moreover, stress often enhances female performance in some of these cognitive tasks. Memory in females is not affected by stress in non-spatial memory tasks like recognition memory and temporal order recognition memory while males show impaired memory following stress. We discuss possible bases for these sex-dependent differences including the use of different strategies by the sexes to solve cognitive tasks. Whether the sex differences result from changes in non-mnemonic factors is also considered. Sex-dependent differences in alcohol and drug influences on stress responses are also described. Finally, the role of neurally derived estradiol in driving sex differences and providing resilience to stress in females is shown. The importance of determining the nature and extent of sex differences in stress responses is that such differences may provide vital information for understanding why some stress related diseases have different incidence rates between the sexes and for developing novel therapeutic treatments. Copyright © 2016 Elsevier Inc. All rights reserved.

    19. Rodent models of congenital and hereditary cataract in man.

      Science.gov (United States)

      Tripathi, B J; Tripathi, R C; Borisuth, N S; Dhaliwal, R; Dhaliwal, D

      1991-01-01

      Because the organogenesis and physiology of the lens are essentially similar in various mammals, an understanding of the etiology and pathogenesis of the formation of cataract in an animal model will enhance our knowledge of cataractogenesis in man. In this review, we summarize the background, etiology, and pathogenesis of cataracts that occur in rodents. The main advantages of using rodent mutants include the well-researched genetics of the animals and the comparative ease of breeding of large litters. Numerous rodent models of congenital and hereditary cataracts have been studied extensively. In mice, the models include the Cts strain, Fraser mouse, lens opacity gene (Lop) strain, Lop-2 and Lop-3 strains, Philly mouse, Nakano mouse, Nop strain, Deer mouse, Emory mouse, Swiss Webster strain, Balb/c-nct/nct mouse, and SAM-R/3 strain. The rat models include BUdR, ICR, Sprague-Dawley, and Wistar rats, the spontaneously hypertensive rat (SHR), the John Rapp inbred strain of Dahl salt-sensitive rat, as well as WBN/Kob, Royal College of Surgeons (RCS), and Brown-Norway rats. Other proposed models for the study of hereditary cataract include the degu and the guinea pig. Because of the ease of making clinical observations in vivo and the subsequent availability of the intact lens for laboratory analyses at different stages of cataract formation, these animals provide excellent models for clinicopathologic correlations, for monitoring of the natural history of the aging process and of metabolic defects, as well as for investigations on the effect of cataract-modulating agents and drugs, including the prospect of gene therapy.

    20. Ghrelin influences novelty seeking behavior in rodents and men.

      Science.gov (United States)

      Hansson, Caroline; Shirazi, Rozita H; Näslund, Jakob; Vogel, Heike; Neuber, Corinna; Holm, Göran; Anckarsäter, Henrik; Dickson, Suzanne L; Eriksson, Elias; Skibicka, Karolina P

      2012-01-01

      Recent discoveries indicate an important role for ghrelin in drug and alcohol reward and an ability of ghrelin to regulate mesolimbic dopamine activity. The role of dopamine in novelty seeking, and the association between this trait and drug and alcohol abuse, led us to hypothesize that ghrelin may influence novelty seeking behavior. To test this possibility we applied several complementary rodent models of novelty seeking behavior, i.e. inescapable novelty-induced locomotor activity (NILA), novelty-induced place preference and novel object exploration, in rats subjected to acute ghrelin receptor (growth hormone secretagogue receptor; GHSR) stimulation or blockade. Furthermore we assessed the possible association between polymorphisms in the genes encoding ghrelin and GHSR and novelty seeking behavior in humans. The rodent studies indicate an important role for ghrelin in a wide range of novelty seeking behaviors. Ghrelin-injected rats exhibited a higher preference for a novel environment and increased novel object exploration. Conversely, those with GHSR blockade drastically reduced their preference for a novel environment and displayed decreased NILA. Importantly, the mesolimbic ventral tegmental area selective GHSR blockade was sufficient to reduce the NILA response indicating that the mesolimbic GHSRs might play an important role in the observed novelty responses. Moreover, in untreated animals, a striking positive correlation between NILA and sucrose reward behavior was detected. Two GHSR single nucleotide polymorphisms (SNPs), rs2948694 and rs495225, were significantly associated with the personality trait novelty seeking, as assessed using the Temperament and Character Inventory (TCI), in human subjects. This study provides the first evidence for a role of ghrelin in novelty seeking behavior in animals and humans, and also points to an association between food reward and novelty seeking in rodents.

    1. Patterns of orthopox virus wild rodent hosts in South Germany.

      Science.gov (United States)

      Essbauer, Sandra; Hartnack, Sonja; Misztela, Krystian; Kiessling-Tsalos, Judith; Bäumler, Walter; Pfeffer, Martin

      2009-06-01

      Although cowpox virus (CPXV) infections in a variety of dead-end hosts have been investigated in Germany for more than 50 years, data on species and geographical distribution of CPXV in reservoir hosts are sparse. Here we present the first comprehensive study of 825 rodents that have been collected in Bavaria, Southern Germany. In summary, six different rodent species (Apodemus flavicollis, Myodes glareolus, Microtus arvalis, Apodemus sylvaticus, Microtus agrestis, and Arvicola amphibius) were trapped at three main trapping sites and investigated using a serum neutralization test (SNT). Prevalence of orthopox virus (OPV)-neutralizing antibodies was (with exception of one trapping site) highest in bank voles, ranging from 24.5% to 42.4%; often with SNT titers > or =96. Two up to 25% of yellow-necked mice were OPV sero-positive, but wood mice only at one site with 5.5%. Up to 7.7% of common voles were found to be OPV seroreactive, while M. agrestis and A. amphibius only sporadically showed seroreactivity. Further analyses of a subset of 450 bank voles and yellow-necked mice trapped at one site over a 18-month period revealed that male yellow-necked mice and female gravid yellow-necked mice had significantly more OPV-neutralizing antibodies. Mean body weight and OPV-seroreactivity were significantly negatively associated in male A. flavicollis. This was not due to shorter body length or smaller body mass index, but previously OPV-infected male A. flavicollis had dramatically reduced mean kidney weights. Seroreactivity in female bank voles was positively related to lung weights. We also found that both male yellow-necked mice and male bank voles with positive SNT titers had higher infestation rates with ectoparasites. We here show for the first time that A. flavicollis beside M. glareolus is a hypothetic host for CPXV, and that there are big geographical and spatial variations concerning the seroprevalence in rodent populations in South Germany.

    2. Polycystic echinococcosis in Colombia: the larval cestodes in infected rodents.

      Science.gov (United States)

      Morales, G A; Guzman, V H; Wells, E A; Angel, D

      1979-07-01

      Described are the characteristics of the polycystic larval cestodes found in an endemic area of echinococcosis in the Easter Plains of Colombia and the tissue reaction evoked in infected rodents. Of 848 free-ranging animals examined, polycystic hydatids were found in 44/93 Cuniculus paca and 1/369 Proechimys sp. None of 20 Dasyprocta fuliginosa examined was infected, but hunters provided a heart with hydatid cysts and information about two additional animals with infected livers. Recognition of an endemic area of polycystic echinococcosis provides a means to investigate the life cycle of the parasites and to study the histogenesis of the larval cestodes in susceptible laboratory animals.

    3. Nonhuman gamblers: lessons from rodents, primates, and robots

      Science.gov (United States)

      Paglieri, Fabio; Addessi, Elsa; De Petrillo, Francesca; Laviola, Giovanni; Mirolli, Marco; Parisi, Domenico; Petrosino, Giancarlo; Ventricelli, Marialba; Zoratto, Francesca; Adriani, Walter

      2014-01-01

      The search for neuronal and psychological underpinnings of pathological gambling in humans would benefit from investigating related phenomena also outside of our species. In this paper, we present a survey of studies in three widely different populations of agents, namely rodents, non-human primates, and robots. Each of these populations offers valuable and complementary insights on the topic, as the literature demonstrates. In addition, we highlight the deep and complex connections between relevant results across these different areas of research (i.e., cognitive and computational neuroscience, neuroethology, cognitive primatology, neuropsychiatry, evolutionary robotics), to make the case for a greater degree of methodological integration in future studies on pathological gambling. PMID:24574984

    4. Do farming practices influence population dynamics of rodents?

      DEFF Research Database (Denmark)

      Massawe, A W; Rwamugira, W; Leirs, Herwig

      2007-01-01

      A capture-mark-recapture study was conducted in crop fields in Morogoro, Tanzania, to investigate how the population dynamics of multimammate field rats, Mastomys natalensis, was influenced by the commonly practised land preparation methods and cropping systems. Two land preparation methods (trac...... practices. In maize fields in Tanzania, the crop is most susceptible to damage by M. natalensis in the first 2 weeks after planting, and therefore, lower densities of rodents will result into lower crop damage in tractor ploughed fields....

    5. Catecholamines of the body tissues and radiosensitivity of rodents

      Energy Technology Data Exchange (ETDEWEB)

      Grayevskaya, V M; Zolotariova, N N [AN SSSR, Moscow. Inst. Morfologii Zhivotnykh

      1975-01-01

      Various species of rodents are distinguished by their radiosensitivity (increasing): bank vole < Wistar rat < wild mouse < CC/sub 57/Br mouse < golden hamster < BALB mouse < guinea pig. There is a positive correlation between radiosensitivity of these species and catecholamines content in the adrenals, urea and blood; and negative correlation between radiosensitivity and adrenaline and noradrenaline concentrations in liver and spleen cells. Presumable causes of this correlation, and the possibility of application of the index under study for predicting the organism radiosensitivity and forecasting the outcome of radiation damage are discussed.

    6. Catecholamines of the body tissues and radiosensitivity of rodents

      International Nuclear Information System (INIS)

      Grayevskaya, V.M.; Zolotariova, N.N.

      1975-01-01

      Various species of rodents are distinguished by their radiosensitivity (increasing): bank vole 57 Br mouse < golden hamster < BALB mouse < guinea pig. There is a positive correlation between radiosensitivity of these species and catecholamines content in the adrenals, urea and blood; and negative correlation between radiosensitivity and adrenaline and noradrenaline concentrations in liver and spleen cells. Presumable causes of this correlation, and the possibility of application of the index under study for predicting the organism radiosensitivity and forecasting the outcome of radiation damage are discussed

    7. The role of rodents in avian influenza outbreaks in poultry farms: a review.

      Science.gov (United States)

      Velkers, Francisca C; Blokhuis, Simon J; Veldhuis Kroeze, Edwin J B; Burt, Sara A

      2017-12-01

      Wild migratory birds are associated with global avian influenza virus (AIV) spread. Although direct contact with wild birds and contaminated fomites is unlikely in modern non-free range poultry farms applying biosecurity measures, AIV outbreaks still occur. This suggests involvement of other intermediate factors for virus transmission between wild birds and poultry. This review describes current evidence of the potential role of rodents in AIV transmission from wild birds to poultry and between poultry houses. Rodents can be abundant around poultry houses, share their habitat with waterfowl and can readily enter poultry houses. Survival of AIV from waterfowl in poultry house surroundings and on the coat of rodents suggests that rodents are likely to act as mechanical vector. AIVs can replicate in rodents without adaptation, resulting in high viral titres in lungs and nasal turbinates, virus presence in nasal washes and saliva, and transmission to naïve contact animals. Therefore, active AIV shedding by infected rodents may play a role in transmission to poultry. Further field and experimental studies are needed to provide evidence for a role of rodents in AIV epidemiology. Making poultry houses rodent-proof and the immediate surroundings unattractive for rodents are recommended as preventive measures against possible AIV introduction.

    8. Multiple Co-infections of Rodents with Hantaviruses, Leptospira, and Babesia in Croatia

      Science.gov (United States)

      Turk, Nenad; Korva, Miša; Margaletić, Josip; Beck, Relja; Vucelja, Marko; Habuš, Josipa; Svoboda, Petra; Županc, Tatjana Avšič; Henttonen, Heikki; Markotić, Alemka

      2012-01-01

      Abstract Hantaviruses, Leptospira spp., and Babesia spp. are rodent-borne pathogens present worldwide. We studied multiple co-infections of small rodents in Croatia with all three pathogens. Twenty-eight Apodemus flavicollis and 16 Myodes glareolus were tested for the presence of hantavirus RNA by real-time RT-PCR, Leptospira strains by renoculture method and Babesia DNA by PCR. Anti-hantavirus antibodies and anti-Leptospira antibodies were detected by serological methods. Very high infection rates with each pathogen were found in A. flavicollis: 20 of 28 rodents (71%) were infected with Dobrava virus, 13 rodents (46%) were infected with Leptospira, and 5 rodents (18%) were infected with Babesia. Multiple co-infections with all three pathogens were found in 3 of 28 (11%) A. flavicollis animals, suggesting that the same rodent host can be infected with several pathogens at the same time. Dual infections with both hantaviruses and Leptospira were found in 7 of 44 rodents (16%), with hantaviruses and Babesia in 2 rodents (5%), and double infection with both Leptospira and Babesia were found in 1 rodent (2%). Since hantaviruses, Leptospira, and Babesia have similar geographical distributions, it is to be expected that in other parts of the world multiple co-infections, representing a serious threat to public health, can be found. PMID:22217170

    9. Specific diversity and morphological indices of muriform rodents in some areas of Semipalatinsk test range zone

      International Nuclear Information System (INIS)

      Magda, I.N.; Chernykh, A.B.; Morozov, A.E.; Bushneva, I.A.; Ponyavkina, A.G.

      2002-01-01

      There were presented the results of the preliminary estimation of comparative specific diversity and morphological indices of muriform rodents inhabiting separate areas of the Semipalatinsk test site. (author)

    10. Rodent Species Distribution and Hantavirus Seroprevalence in Residential and Forested areas of Sarawak, Malaysia.

      Science.gov (United States)

      Hamdan, Nur Elfieyra Syazana; Ng, Yee Ling; Lee, Wei Bin; Tan, Cheng Siang; Khan, Faisal Ali Anwarali; Chong, Yee Ling

      2017-01-01

      Rodents belong to the order Rodentia, which consists of three families in Borneo (i.e., Muridae, Sciuridae and Hystricidae). These include rats, mice, squirrels, and porcupines. They are widespread throughout the world and considered pests that harm humans and livestock. Some rodent species are natural reservoirs of hantaviruses (Family: Bunyaviridae) that can cause zoonotic diseases in humans. Although hantavirus seropositive human sera were reported in Peninsular Malaysia in the early 1980s, information on their infection in rodent species in Malaysia is still lacking. The rodent populations in residential and forested areas in Sarawak were sampled. A total of 108 individuals from 15 species of rodents were collected in residential ( n = 44) and forested ( n = 64) areas. The species diversity of rodents in forested areas was significantly higher (H = 2.2342) compared to rodents in residential areas (H = 0.64715) ( p Sarawak, East Malaysia. The results suggested that hantavirus was not circulating in the studied rodent populations in Sarawak, or it was otherwise at a low prevalence that is below the detection threshold. It is important to remain vigilant because of the zoonotic potential of this virus and its severe disease outcome. Further studies, such as molecular detection of viral genetic materials, are needed to fully assess the risk of hantavirus infection in rodents and humans in this region of Malaysia.

    11. Normas percibidas por los estudiantes universitarios de enfermería acerca de sus pares y el uso de drogas en Lima, Perú Normas percebidas por estudantes universitários de enfermagem sobre seus pares e o uso de drogas, em Lima, Peru Perceived norms among nursing students about their peers and drug use in Lima, Peru

      Directory of Open Access Journals (Sweden)

      Eva Chaname

      2009-01-01

      Full Text Available Con el objetivo de estimar la diferencia entre las normas percibidas sobre el uso de drogas por los pares y el uso real de drogas entre estudiantes universitarios se efectuó un estudio cuantitativo transversal, basado en una encuesta de 196 estudiantes de enfermería de Lima. Se utilizó un cuestionario que midió la percepción del uso de drogas y el propio uso. La información fue analizada con estadística descriptiva; fue considerando un valor mayor, menor o igual a 10% para establecer la diferencia. Las normas percibidas para alcohol y tabaco fueron mayores de 50%, mientras que para marihuana y cocaína fue de 6%. El 57,7% informó haber usado tabaco, 84,7% alcohol, 2,6% marihuana y 1% cocaína; se encontró que existe sobreestimación sobre el uso de marihuana y cocaína, subestimación para el alcohol, y percepción exacta para el uso de tabaco. Los resultados serán de utilidad para sensibilizar a las autoridades universitarias e para implementar políticas o programas de prevención.Com o objetivo de estimar a diferença entre as normas percebidas sobre o uso de drogas por estudantes universitários, foi realizado estudo quantitativo transversal, baseado em censo com 196 estudantes de enfermagem de Lima, Peru. Utilizou-se questionário com a finalidade de medir a percepção do uso de drogas e do próprio uso, analisando-se a informação com estatística descritiva, considerando valor maior, menor ou igual a 10 pontos para estabelecer a diferença. As normas percebidas para o álcool e tabaco foram maiores que 50%, enquanto que para maconha e cocaína foi de 6%; 57,7% referiram ter usado tabaco, 84,7% álcool, 2,6% maconha e 1% cocaína. Existe superestimação do uso de maconha e cocaína, subestimação para o uso de álcool e percepção exata para o uso de tabaco. Os resultados são úteis para sensibilizar as autoridades universitárias e implementar políticas de prevenção.This quantitative, cross-sectional study was performed

    12. Evaluation of NASA Foodbars as a Standard Diet for Use in Short-Term Rodent Space Flight Studies

      Science.gov (United States)

      Tou, Janet; Grindeland, Richard; Barrett, Joyce; Dalton, Bonnie; Mandel, Adrian; Wade, Charles

      2003-01-01

      A standard rodent diet for space flight must meet the unique conditions imposed by the space environment and must be nutritionally adequate since diet can influence the outcome of experiments. This paper evaluates the use of National Aeronautics and Space Administration (NASA) developed Foodbars as a standard space flight diet for rats. The Foodbar's semi-purified formulation permits criteria such as nutrient consistency, high nutrient bioavailability and flexibility of formulation to be met. Extrusion of the semi-purified diet produces Foodbars with the proper texture and a non-crumbing solid form for use in space. Treatment of Foodbar with 0.1% potassium sorbate prevents mold growth. Irradiation (15-25 kGy) prevents bacterial growth and in combination with sorbate-treatment provides added protection against mold for shelf-stability. However, during the development process, nutrient analyses indicated that extrusion and irradiation produced nutrient losses. Nutrients were adjusted accordingly to compensate for processing losses. Nutrient analysis of Foodbars continues to be performed routinely to monitor nutrient levels. It is important that the standard rodent diet provide nutrients that will prevent deficiency but also avoid excess that may mask physiological changes produced by space flight. All vitamins levels in the Foodbars, except for vitamin K conformed to or exceeded the current NRC (1995) recommendations. All indispensable amino acids in Foodbar conformed to or exceeded the NRC nutrient recommendation for mice growth and rat maintenance. However, some indispensable amino acids were slightly below recommendations for rat reproduction/growth. Short-term (18-20 d) animal feeding studies indicated that Foodbars were palatable, supported growth and maintained health in rats. Results indicated that NASA rodent Foodbars meet both the physical and nutritional criteria required to support rodents in the space environment and thus, may be used successfully as a

    13. Effects of Strain and Species on the Septo-Temporal Distribution of Adult Neurogenesis in Rodents

      Directory of Open Access Journals (Sweden)

      Franziska Wiget

      2017-12-01

      Full Text Available The functional septo-temporal (dorso-ventral differentiation of the hippocampus is accompanied by gradients of adult hippocampal neurogenesis (AHN in laboratory rodents. An extensive septal AHN in laboratory mice suggests an emphasis on a relation of AHN to tasks that also depend on the septal hippocampus. Domestication experiments indicate that AHN dynamics along the longitudinal axis are subject to selective pressure, questioning if the septal emphasis of AHN in laboratory mice is a rule applying to rodents in general. In this study, we used C57BL/6 and DBA2/Crl mice, wild-derived F1 house mice and wild-captured wood mice and bank voles to look for evidence of strain and species specific septo-temporal differences in AHN. We confirmed the septal > temporal gradient in C57BL/6 mice, but in the wild species, AHN was low septally and high temporally. Emphasis on the temporal hippocampus was particularly strong for doublecortin positive (DCX+ young neurons and more pronounced in bank voles than in wood mice. The temporal shift was stronger in female wood mice than in males, while we did not see sex differences in bank voles. AHN was overall low in DBA and F1 house mice, but they exhibited the same inversed gradient as wood mice and bank voles. DCX+ young neurons were usually confined to the subgranular zone and deep granule cell layer. This pattern was seen in all animals in the septal and intermediate dentate gyrus. In bank voles and wood mice however, the majority of temporal DCX+ cells were radially dispersed throughout the granule cell layer. Some but not all of the septo-temporal differences were accompanied by changes in the DCX+/Ki67+ cell ratios, suggesting that new neuron numbers can be regulated by both proliferation or the time course of maturation and survival of young neurons. Some of the septo-temporal differences we observe have also been found in laboratory rodents after the experimental manipulation of the molecular mechanisms

    14. Rodent ultrasonic vocalizations are bound to active sniffing behavior

      Directory of Open Access Journals (Sweden)

      Yevgeniy B Sirotin

      2014-11-01

      Full Text Available During rodent active behavior, multiple orofacial sensorimotor behaviors, including sniffing and whisking, display rhythmicity in the theta range (~5-10 Hz. During specific behaviors, these rhythmic patterns interlock, such that execution of individual motor programs becomes dependent on the state of the others. Here we performed simultaneous recordings of the respiratory cycle and ultrasonic vocalization emission by adult rats and mice in social settings. We used automated analysis to examine the relationship between breathing patterns and vocalization over long time periods. Rat ultrasonic vocalizations (USVs, ’50 kHz’ were emitted within stretches of active sniffing (5−10 Hz and were largely absent during periods of passive breathing (1-4 Hz. Because ultrasound was tightly linked to the exhalation phase, the sniffing cycle segmented vocal production into discrete calls and imposed its theta rhythmicity on their timing. In turn, calls briefly prolonged exhalations, causing an immediate drop in sniffing rate. Similar results were obtained in mice. Our results show that ultrasonic vocalizations are an integral part of the rhythmic orofacial behavioral ensemble. This complex behavioral program is thus involved not only in active sensing but also in the temporal structuring of social communication signals. Many other social signals of mammals, including monkey calls and human speech, show structure in the theta range. Our work points to a mechanism for such structuring in rodent ultrasonic vocalizations.

    15. Population Ecology of Hantavirus Rodent Hosts in Southern Brazil

      Science.gov (United States)

      Teixeira, Bernardo R.; Loureiro, Nathalie; Strecht, Liana; Gentile, Rosana; Oliveira, Renata C.; Guterres, Alexandro; Fernandes, Jorlan; Mattos, Luciana H. B. V.; Raboni, Sonia M.; Rubio, Giselia; Bonvicino, Cibele R.; Duarte dos Santos, Claudia N.; Lemos, Elba R. S.; D'Andrea, Paulo S.

      2014-01-01

      In this study we analyze population dynamics of hantavirus rodent hosts and prevalence of infection over a 2-year period in Southern Brazil, a region with a high incidence of hantavirus pulmonary syndrome. The 14 small mammal species captured were composed of 10 rodents and four marsupials, the six most abundant species being Akodon serrensis, Oxymycterus judex, Akodon montensis, Akodon paranaensis, Oligoryzomys nigripes, and Thaptomys nigrita. These species displayed a similar pattern with increasing population sizes in fall/winter caused by recruitment and both, increase in reproductive activity and higher hantavirus prevalence in spring/summer. Specific associations between A. montensis/Jaborá Virus (JABV) and O. nigripes/Juquitiba-like Virus (JUQV-like) and spillover infections between A. paranaensis/JABV, A. serrensis/JABV, and A. paranaensis/JUQV-like were observed. Spillover infection in secondary hosts seems to play an important role in maintaining JABV and JUQV-like in the hantavirus sylvatic cycle mainly during periods of low prevalence in primary hosts. PMID:24935954

    16. Functional evolution of the feeding system in rodents.

      Directory of Open Access Journals (Sweden)

      Philip G Cox

      Full Text Available The masticatory musculature of rodents has evolved to enable both gnawing at the incisors and chewing at the molars. In particular, the masseter muscle is highly specialised, having extended anteriorly to originate from the rostrum. All living rodents have achieved this masseteric expansion in one of three ways, known as the sciuromorph, hystricomorph and myomorph conditions. Here, we used finite element analysis (FEA to investigate the biomechanical implications of these three morphologies, in a squirrel, guinea pig and rat. In particular, we wished to determine whether each of the three morphologies is better adapted for either gnawing or chewing. Results show that squirrels are more efficient at muscle-bite force transmission during incisor gnawing than guinea pigs, and that guinea pigs are more efficient at molar chewing than squirrels. This matches the known diet of nuts and seeds that squirrels gnaw, and of grasses that guinea pigs grind down with their molars. Surprisingly, results also indicate that rats are more efficient as well as more versatile feeders than both the squirrel and guinea pig. There seems to be no compromise in biting efficiency to accommodate the wider range of foodstuffs and the more general feeding behaviour adopted by rats. Our results show that the morphology of the skull and masticatory muscles have allowed squirrels to specialise as gnawers and guinea pigs as chewers, but that rats are high-performance generalists, which helps explain their overwhelming success as a group.

    17. Studying autism in rodent models: reconciling endophenotypes with comorbidities.

      Directory of Open Access Journals (Sweden)

      Andrew eArgyropoulos

      2013-07-01

      Full Text Available Autism spectrum disorder (ASD patients commonly exhibit a variety of comorbid traits including seizures, anxiety, aggressive behavior, gastrointestinal problems, motor deficits, abnormal sensory processing and sleep disturbances for which the cause is unknown. These features impact negatively on daily life and can exaggerate the effects of the core diagnostic traits (social communication deficits and repetitive behaviors. Studying endophenotypes relevant to both core and comorbid features of ASD in rodent models can provide insight into biological mechanisms underlying these disorders. Here we review the characterization of endophenotypes in a selection of environmental, genetic and behavioural rodent models of ASD. In addition to exhibiting core ASD-like behaviours, each of these animal models display one or more endophenotypes relevant to comorbid features including altered sensory processing, seizure susceptibility, anxiety-like behaviour and disturbed motor functions, suggesting that these traits are indicators of altered biological pathways in ASD. However, the study of behaviours paralleling comorbid traits in animal models of ASD is an emerging field and further research is needed to assess altered gastrointestinal function, aggression and disorders of sleep onset across models. Future studies should include investigation of these endophenotypes in order to advance our understanding of the etiology of this complex disorder.

    18. Morphology captures diet and locomotor types in rodents.

      Science.gov (United States)

      Verde Arregoitia, Luis D; Fisher, Diana O; Schweizer, Manuel

      2017-01-01

      To understand the functional meaning of morphological features, we need to relate what we know about morphology and ecology in a meaningful, quantitative framework. Closely related species usually share more phenotypic features than distant ones, but close relatives do not necessarily have the same ecologies. Rodents are the most diverse group of living mammals, with impressive ecomorphological diversification. We used museum collections and ecological literature to gather data on morphology, diet and locomotion for 208 species of rodents from different bioregions to investigate how morphological similarity and phylogenetic relatedness are associated with ecology. After considering differences in body size and shared evolutionary history, we find that unrelated species with similar ecologies can be characterized by a well-defined suite of morphological features. Our results validate the hypothesized ecological relevance of the chosen traits. These cranial, dental and external (e.g. ears) characters predicted diet and locomotion and showed consistent differences among species with different feeding and substrate use strategies. We conclude that when ecological characters do not show strong phylogenetic patterns, we cannot simply assume that close relatives are ecologically similar. Museum specimens are valuable records of species' phenotypes and with the characters proposed here, morphology can reflect functional similarity, an important component of community ecology and macroevolution.

    19. The Need for Speed in Rodent Locomotion Analyses

      Science.gov (United States)

      Batka, Richard J.; Brown, Todd J.; Mcmillan, Kathryn P.; Meadows, Rena M.; Jones, Kathryn J.; Haulcomb, Melissa M.

      2016-01-01

      Locomotion analysis is now widely used across many animal species to understand the motor defects in disease, functional recovery following neural injury, and the effectiveness of various treatments. More recently, rodent locomotion analysis has become an increasingly popular method in a diverse range of research. Speed is an inseparable aspect of locomotion that is still not fully understood, and its effects are often not properly incorporated while analyzing data. In this hybrid manuscript, we accomplish three things: (1) review the interaction between speed and locomotion variables in rodent studies, (2) comprehensively analyze the relationship between speed and 162 locomotion variables in a group of 16 wild-type mice using the CatWalk gait analysis system, and (3) develop and test a statistical method in which locomotion variables are analyzed and reported in the context of speed. Notable results include the following: (1) over 90% of variables, reported by CatWalk, were dependent on speed with an average R2 value of 0.624, (2) most variables were related to speed in a nonlinear manner, (3) current methods of controlling for speed are insufficient, and (4) the linear mixed model is an appropriate and effective statistical method for locomotion analyses that is inclusive of speed-dependent relationships. Given the pervasive dependency of locomotion variables on speed, we maintain that valid conclusions from locomotion analyses cannot be made unless they are analyzed and reported within the context of speed. PMID:24890845

    20. Conspecific Interactions in Adult Laboratory Rodents: Friends or Foes?

      Science.gov (United States)

      Lukas, Michael; de Jong, Trynke R

      2017-01-01

      Interactions between adult conspecifics, including sexual behaviors, affiliation, and aggression are crucial for the well-being, survival, and reproduction of mammals. This holds true for any mammalian species, but certainly for humans: An inability to optimally navigate the social system can have a strong negative impact on physical and mental health. Translational rodent models have been used for decades to unravel the neural pathways and substrates involved in normal and abnormal conspecific interactions. Researchers in the field of translational social neuroscience face a double challenge: Not only do they need to pay considerable attention to the behavioral ecology of their model species or their ancestors, they also have to expect a relatively large variability in behavior and adjust their experimental design accordingly. In this chapter, we will lay out traditional and novel rodent models and paradigms to study sexual, affiliative, and aggressive interactions among adult conspecifics. We will discuss the merits and main findings and briefly consider the most promising novel directions. Finally, we review the modulatory involvement of two major players in mammal social interaction: the central oxytocin and vasopressin system.

    1. New Insights from Rodent Models of Fatty Liver Disease

      Science.gov (United States)

      2011-01-01

      Abstract Rodent models of fatty liver disease are essential research tools that provide a window into disease pathogenesis and a testing ground for prevention and treatment. Models come in many varieties involving dietary and genetic manipulations, and sometimes both. High-energy diets that induce obesity do not uniformly cause fatty liver disease; this has prompted close scrutiny of specific macronutrients and nutrient combinations to determine which have the greatest potential for hepatotoxicity. At the same time, diets that do not cause obesity or the metabolic syndrome but do cause severe steatohepatitis have been exploited to study factors important to progressive liver injury, including cell death, oxidative stress, and immune activation. Rodents with a genetic predisposition to overeating offer yet another model in which to explore the evolution of fatty liver disease. In some animals that overeat, steatohepatitis can develop even without resorting to a high-energy diet. Importantly, these models and others have been used to document that aerobic exercise can prevent or reduce fatty liver disease. This review focuses primarily on lessons learned about steatohepatitis from manipulations of diet and eating behavior. Numerous additional insights about hepatic lipid metabolism, which have been gained from genetically engineered mice, are also mentioned. Antioxid. Redox Signal. 15, 535–550. PMID:21126212

    2. Causal evidence between monsoon and evolution of rhizomyine rodents.

      Science.gov (United States)

      López-Antoñanzas, Raquel; Knoll, Fabien; Wan, Shiming; Flynn, Lawrence J

      2015-03-11

      The modern Asian monsoonal systems are currently believed to have originated around the end of the Oligocene following a crucial step of uplift of the Tibetan-Himalayan highlands. Although monsoon possibly drove the evolution of many mammal lineages during the Neogene, no evidence thereof has been provided so far. We examined the evolutionary history of a clade of rodents, the Rhizomyinae, in conjunction with our current knowledge of monsoon fluctuations over time. The macroevolutionary dynamics of rhizomyines were analyzed within a well-constrained phylogenetic framework coupled with biogeographic and evolutionary rate studies. The evolutionary novelties developed by these rodents were surveyed in parallel with the fluctuations of the Indian monsoon so as to evaluate synchroneity and postulate causal relationships. We showed the existence of three drops in biodiversity during the evolution of rhizomyines, all of which reflected elevated extinction rates. Our results demonstrated linkage of monsoon variations with the evolution and biogeography of rhizomyines. Paradoxically, the evolution of rhizomyines was accelerated during the phases of weakening of the monsoons, not of strengthening, most probably because at those intervals forest habitats declined, which triggered extinction and progressive specialization toward a burrowing existence.

    3. Holocene vegetation history from fossil rodent middens near Arequipa, Peru

      Science.gov (United States)

      Holmgren, C.A.; Betancourt, J.L.; Rylander, K.A.; Roque, J.; Tovar, O.; Zeballos, H.; Linares, E.; Quade, Jay

      2001-01-01

      Rodent (Abrocoma, Lagidium, Phyllotis) middens collected from 2350 to 2750 m elevation near Arequipa, Peru (16??S), provide an ???9600-yr vegetation history of the northern Atacama Desert, based on identification of >50 species of plant macrofossils. These midden floras show considerable stability throughout the Holocene, with slightly more mesophytic plant assemblages in the middle Holocene. Unlike the southwestern United States, rodent middens of mid-Holocene age are common. In the Arequipa area, the midden record does not reflect any effects of a mid-Holocene mega drought proposed from the extreme lowstand (100 m below modern levels, >6000 to 3500 yr B.P.) of Lake Titicaca, only 200 km east of Arequipa. This is perhaps not surprising, given other evidence for wetter summers on the Pacific slope of the Andes during the middle Holocene as well as the poor correlation of summer rainfall among modern weather stations in the central AndesAtacama Desert. The apparent difference in paleoclimatic reconstructions suggests that it is premature to relate changes observed during the Holocene to changes in El Nin??o Southern Oscillation modes. ?? 2001 University of Washington.

    4. A Practical Guide to Rodent Islet Isolation and Assessment

      Directory of Open Access Journals (Sweden)

      Carter Jeffrey D

      2009-12-01

      Full Text Available Abstract Pancreatic islets of Langerhans secrete hormones that are vital to the regulation of blood glucose and are, therefore, a key focus of diabetes research. Purifying viable and functional islets from the pancreas for study is an intricate process. This review highlights the key elements involved with mouse and rat islet isolation, including choices of collagenase, the collagenase digestion process, purification of islets using a density gradient, and islet culture conditions. In addition, this paper reviews commonly used techniques for assessing islet viability and function, including visual assessment, fluorescent markers of cell death, glucose-stimulated insulin secretion, and intracellular calcium measurements. A detailed protocol is also included that describes a common method for rodent islet isolation that our laboratory uses to obtain viable and functional mouse islets for in vitro study of islet function, beta-cell physiology, and in vivo rodent islet transplantation. The purpose of this review is to serve as a resource and foundation for successfully procuring and purifying high-quality islets for research purposes.

    5. Spatial memory tasks in rodents: what do they model?

      Science.gov (United States)

      Morellini, Fabio

      2013-10-01

      The analysis of spatial learning and memory in rodents is commonly used to investigate the mechanisms underlying certain forms of human cognition and to model their dysfunction in neuropsychiatric and neurodegenerative diseases. Proper interpretation of rodent behavior in terms of spatial memory and as a model of human cognitive functions is only possible if various navigation strategies and factors controlling the performance of the animal in a spatial task are taken into consideration. The aim of this review is to describe the experimental approaches that are being used for the study of spatial memory in rats and mice and the way that they can be interpreted in terms of general memory functions. After an introduction to the classification of memory into various categories and respective underlying neuroanatomical substrates, I explain the concept of spatial memory and its measurement in rats and mice by analysis of their navigation strategies. Subsequently, I describe the most common paradigms for spatial memory assessment with specific focus on methodological issues relevant for the correct interpretation of the results in terms of cognitive function. Finally, I present recent advances in the use of spatial memory tasks to investigate episodic-like memory in mice.

    6. Evaluating rodent motor functions: Which tests to choose?

      Science.gov (United States)

      Schönfeld, Lisa-Maria; Dooley, Dearbhaile; Jahanshahi, Ali; Temel, Yasin; Hendrix, Sven

      2017-12-01

      Damage to the motor cortex induced by stroke or traumatic brain injury (TBI) can result in chronic motor deficits. For the development and improvement of therapies, animal models which possess symptoms comparable to the clinical population are used. However, the use of experimental animals raises valid ethical and methodological concerns. To decrease discomfort by experimental procedures and to increase the quality of results, non-invasive and sensitive rodent motor tests are needed. A broad variety of rodent motor tests are available to determine deficits after stroke or TBI. The current review describes and evaluates motor tests that fall into three categories: Tests to evaluate fine motor skills and grip strength, tests for gait and inter-limb coordination and neurological deficit scores. In this review, we share our thoughts on standardized data presentation to increase data comparability between studies. We also critically evaluate current methods and provide recommendations for choosing the best behavioral test for a new research line. Copyright © 2017 Elsevier Ltd. All rights reserved.

    7. Peer and sibling substance use: predictors of substance use among adolescents in Mexico El uso de sustancias por pares y hermanos como factor pronóstico del uso de sustancias por adolescentes en México

      Directory of Open Access Journals (Sweden)

      William Latimer

      2004-04-01

      Full Text Available OBJECTIVE: To examine the extent to which peer drug use and sibling drug use predict alcohol abuse/dependence disorder status and the use of drugs other than alcohol among school-based youth in Mexico. METHODS: Data were collected on 1 203 middle and high school students in northern Mexico in May 1998. Participation was voluntary, and responses were confidential. Logistic regression analyses estimated the association that peer drug use and that sibling drug use had with alcohol abuse/dependence diagnosis and the lifetime use of drugs other than alcohol. RESULTS: Students who had siblings or peers who used alcohol and other drugs were more likely to meet the standard alcohol abuse/dependence criteria defined by the Diagnostic and Statistical Manual of Mental Disorders Fourth Edition (DSM-IV, and were more likely to have used drugs other than alcohol. Controlling for potentially important confounders, we found that adolescents with the highest level of peer substance use were eight times as likely to meet alcohol abuse/dependence criteria and four times as likely to use other drugs. Youth who had siblings who used drugs were about twice as likely to meet alcohol abuse/dependence criteria and about 2.5 times as likely to use drugs other than alcohol when compared to youth with no sibling substance use. CONCLUSIONS: Consistent with extant findings among youth in the United States of America, peer and sibling substance use are major risk factors for substance use among school-based youth in Mexico. Students in Mexico may benefit from prevention strategies found to be effective among students in the United States.OBJECTIVO: Examinar en qué medida el uso de drogas por los pares y hermanos es factor pronóstico del abuso o la dependencia del alcohol y del uso de drogas distintas del alcohol en escolares mexicanos. MÉTODOS: Se recolectaron datos acerca de 1 203 estudiantes de los últimos años de primaria y de secundaria en el norte de México en mayo

    8. Rodent-borne diseases and their public health importance in Iran.

      Directory of Open Access Journals (Sweden)

      Mohammad Hasan Rabiee

      2018-04-01

      Full Text Available Rodents are reservoirs and hosts for several zoonotic diseases such as plague, leptospirosis, and leishmaniasis. Rapid development of industry and agriculture, as well as climate change throughout the globe, has led to change or increase in occurrence of rodent-borne diseases. Considering the distribution of rodents throughout Iran, the aim of this review is to assess the risk of rodent-borne diseases in Iran.We searched Google Scholar, PubMed, Science Direct, Scientific Information Database (SID, and Magiran databases up to September 2016 to obtain articles reporting occurrence of rodent-borne diseases in Iran and extract information from them. Out of 70 known rodent-borne diseases, 34 were reported in Iran: 17 (50% parasitic diseases, 13 (38% bacterial diseases, and 4 (12% viral diseases. Twenty-one out of 34 diseases were reported from both humans and rodents. Among the diseases reported in the rodents of Iran, plague, leishmaniasis, and hymenolepiasis were the most frequent. The most infected rodents were Rattus norvegicus (16 diseases, Mus musculus (14 diseases, Rattus rattus (13 diseases, Meriones persicus (7 diseases, Apodemus spp. (5 diseases, Tatera indica (4 diseases, Meriones libycus (3 diseases, Rhombomys opimus (3 diseases, Cricetulus migratorius (3 diseases, and Nesokia indica (2 diseases.The results of this review indicate the importance of rodent-borne diseases in Iran. Considering notable diversity of rodents and their extensive distribution throughout the country, it is crucial to pay more attention to their role in spreading infectious diseases for better control of the diseases.

    9. Rodent-borne diseases and their public health importance in Iran

      Science.gov (United States)

      Mahmoudi, Ahmad; Siahsarvie, Roohollah; Kryštufek, Boris; Mostafavi, Ehsan

      2018-01-01

      Background Rodents are reservoirs and hosts for several zoonotic diseases such as plague, leptospirosis, and leishmaniasis. Rapid development of industry and agriculture, as well as climate change throughout the globe, has led to change or increase in occurrence of rodent-borne diseases. Considering the distribution of rodents throughout Iran, the aim of this review is to assess the risk of rodent-borne diseases in Iran. Methodology/Principal finding We searched Google Scholar, PubMed, Science Direct, Scientific Information Database (SID), and Magiran databases up to September 2016 to obtain articles reporting occurrence of rodent-borne diseases in Iran and extract information from them. Out of 70 known rodent-borne diseases, 34 were reported in Iran: 17 (50%) parasitic diseases, 13 (38%) bacterial diseases, and 4 (12%) viral diseases. Twenty-one out of 34 diseases were reported from both humans and rodents. Among the diseases reported in the rodents of Iran, plague, leishmaniasis, and hymenolepiasis were the most frequent. The most infected rodents were Rattus norvegicus (16 diseases), Mus musculus (14 diseases), Rattus rattus (13 diseases), Meriones persicus (7 diseases), Apodemus spp. (5 diseases), Tatera indica (4 diseases), Meriones libycus (3 diseases), Rhombomys opimus (3 diseases), Cricetulus migratorius (3 diseases), and Nesokia indica (2 diseases). Conclusions/Significance The results of this review indicate the importance of rodent-borne diseases in Iran. Considering notable diversity of rodents and their extensive distribution throughout the country, it is crucial to pay more attention to their role in spreading infectious diseases for better control of the diseases. PMID:29672510

    10. Transient receptor potential channel ankyrin-1 is not a cold sensor for autonomic thermoregulation in rodents.

      Science.gov (United States)

      de Oliveira, Cristiane; Garami, Andras; Lehto, Sonya G; Pakai, Eszter; Tekus, Valeria; Pohoczky, Krisztina; Youngblood, Beth D; Wang, Weiya; Kort, Michael E; Kym, Philip R; Pinter, Erika; Gavva, Narender R; Romanovsky, Andrej A

      2014-03-26

      The rodent transient receptor potential ankyrin-1 (TRPA1) channel has been hypothesized to serve as a temperature sensor for thermoregulation in the cold. We tested this hypothesis by using deletion of the Trpa1 gene in mice and pharmacological blockade of the TRPA1 channel in rats. In both Trpa1(-/-) and Trpa1(+/+) mice, severe cold exposure (8°C) resulted in decreases of skin and deep body temperatures to ∼8°C and 13°C, respectively, both temperatures being below the reported 17°C threshold temperature for TRPA1 activation. Under these conditions, Trpa1(-/-) mice had the same dynamics of body temperature as Trpa1(+/+) mice and showed no weakness in the tail skin vasoconstriction response or thermogenic response to cold. In rats, the effects of pharmacological blockade were studied by using two chemically unrelated TRPA1 antagonists: the highly potent and selective compound A967079, which had been characterized earlier, and the relatively new compound 43 ((4R)-1,2,3,4-tetrahydro-4-[3-(3-methoxypropoxy)phenyl]-2-thioxo-5H-indeno[1,2-d]pyrimidin-5-one), which we further characterized in the present study and found to be highly potent (IC50 against cold of ∼8 nm) and selective. Intragastric administration of either antagonist at 30 mg/kg before severe (3°C) cold exposure did not affect the thermoregulatory responses (deep body and tail skin temperatures) of rats, even though plasma concentrations of both antagonists well exceeded their IC50 value at the end of the experiment. In the same experimental setup, blocking the melastatin-8 (TRPM8) channel with AMG2850 (30 mg/kg) attenuated cold-defense mechanisms and led to hypothermia. We conclude that TRPA1 channels do not drive autonomic thermoregulatory responses to cold in rodents.

    11. Stress in adolescence and drugs of abuse in rodent models: Role of dopamine, CRF, and HPA axis

      Science.gov (United States)

      Burke, Andrew R.; Miczek, Klaus A.

      2014-01-01

      Rationale Research on adolescence and drug abuse increased substantially in the past decade. However, drug-addiction related behaviors following stressful experiences during adolescence are less studied. We focus on rodent models of adolescent stress cross-sensitization to drugs of abuse. Objectives Review the ontogeny of behavior, dopamine, corticotropin-releasing factor (CRF), and the hypothalamic pituitary adrenal (HPA) axis in adolescent rodents. We evaluate evidence that stressful experiences during adolescence engender hypersensitivity to drugs of abuse and offer potential neural mechanisms. Results and Conclusions Much evidence suggests that final maturation of behavior, dopamine systems, and HPA axis occurs during adolescence. Stress during adolescence increases amphetamine- and ethanol-stimulated locomotion, preference, and self-administration under many conditions. The influence of adolescent stress on subsequent cocaine- and nicotine-stimulated locomotion and preference is less clear. The type of adolescent stress, temporal interval between stress and testing, species, sex, and the drug tested are key methodological determinants for successful cross-sensitization procedures. The sensitization of the mesolimbic dopamine system is proposed to underlie stress cross-sensitization to drugs of abuse in both adolescents and adults through modulation by CRF. Reduced levels of mesocortical dopamine appear to be a unique consequence of social stress during adolescence. Adolescent stress may reduce the final maturation of cortical dopamine through D2 dopamine receptor regulation of dopamine synthesis or glucocorticoid-facilitated pruning of cortical dopamine fibers. Certain rodent models of adolescent adversity are useful for determining neural mechanisms underlying the cross-sensitization to drugs of abuse. PMID:24370534

    12. Molecular Survey of Zoonotic Agents in Rodents and Other Small Mammals in Croatia.

      Science.gov (United States)

      Tadin, Ante; Tokarz, Rafal; Markotić, Alemka; Margaletić, Josip; Turk, Nenad; Habuš, Josipa; Svoboda, Petra; Vucelja, Marko; Desai, Aaloki; Jain, Komal; Lipkin, W Ian

      2016-02-01

      Croatia is a focus for many rodent-borne zoonosis. Here, we report a survey of 242 rodents and small mammals, including 43 Myodes glareolus, 131 Apodemus flavicollis, 53 Apodemus agrarius, three Apodemus sylvaticus, six Sorex araneus, four Microtus arvalis, one Microtus agrestis, and one Muscardinus avellanarius, collected at eight sites in Croatia over an 8-year period. Multiplex MassTag polymerase chain reaction (PCR) was used for detection of Borrelia, Rickettsia, Bartonella, Babesia, Ehrlichia, Anaplasma, Francisella tularensis, and Coxiella burnetii. Individual PCR assays were used for detection of Leptospira, lymphocytic choriomeningitis virus, orthopoxviruses, flaviviruses, hantaviruses, and Toxoplasma gondii. Of the rodents, 52 (21.5%) were infected with Leptospira, 9 (3.7%) with Borrelia miyamotoi, 5 (2%) with Borrelia afzelii, 29 (12.0%) with Bartonella, 8 (3.3%) with Babesia microti, 2 (0.8%) with Ehrlichia, 4 (1.7%) with Anaplasma, 2 (0.8%) with F. tularensis, 43 (17.8%) with hantaviruses, and 1 (0.4%) with an orthopoxvirus. Other agents were not detected. Multiple infections were found in 32 rodents (13.2%): dual infections in 26 rodents (10.7%), triple infections in four rodents (2.9%), and quadruple infections in two rodents (0.8%). Our findings indicate that rodents in Croatia harbor a wide range of bacteria and viruses that are pathogenic to humans. © The American Society of Tropical Medicine and Hygiene.

    13. An early warning system for IPM-based rodent control in smallholder farming systems in Tanzania

      DEFF Research Database (Denmark)

      Mwanjabe, Patrick S.; Leirs, Herwig

      1997-01-01

      numbers increased faster. Where abundant short rains were a normal condition returning every year, such effect was not clear. A method to assess rodent damage to germinating seedlings was found to be robust and can be used for monitoring rodent problems. Using this assessment technique, we showed...

    14. Natural Intestinal Protozoa in Rodents (Rodentia: Gerbillinae, Murinae, Cricetinae in Northwestern Iran

      Directory of Open Access Journals (Sweden)

      Mehdi MOHEBALI

      2017-09-01

      Full Text Available Background: Majority of parasitic infections in rodents have zoonotic importance. This study aimed to determine the frequency and intensity of intestinal protozoa infections of rodents including Meriones persicus, Mus musculus and, Cricetulus migratorius.Methods: This survey was conducted in Meshkin Shahr district in northwestern Iran from Mar. to Dec. of 2014. Intestinal samples of 204 rodents including M. persicus (n=117, M. musculus (n=63 and C. migratorius (n=24 were parasitologically examined. Formalin-ether concentration method was done for all of rodents stool samples and observed with light microscope. All of suspected cases were stained with trichorome staining Method. Cultivation in dichromate potassium 2.5% was carried out for all of coccidian positive samples. Acid fast and aniline blue staining methods were used for detecting of coccidian oocysts and intestinal microsporidial spores, respectively.Results: About 121(59.3% of the caught rodents were generally infected with intestinal protozoa. Entamoeba muris 14(6.9%, Trichomonas muris 55(27.0%, Chilomastix betencourtti 17 (8.3%, Giardia muris 19(9.3%, Eimeria spp. 46(22.5%, Isospora spp. 4(2% and Cryptosporidium spp. 1(0.5% were found from the collected rodents. Microsporidian spores were identified in 63 (31% out of the 204 collected rodents using aniline blue staining method.Conclusion: Since some of the infections are zoonotic importance thus, control of rodents can be decreased new cases of the parasitic zoonoses in humans.

    15. Natural Intestinal Protozoa in Rodents (Rodentia: Gerbillinae, Murinae, Cricetinae) in Northwestern Iran

      Science.gov (United States)

      MOHEBALI, Mehdi; ZAREI, Zabiholah; Khanaliha, Khadijeh; KIA, Eshrat Beigom; MOTAVALLI-HAGHI, Afsaneh; DAVOODI, Jaber; REZAEIAN, Tahereh; TARIGHI, Fathemeh; REZAEIAN, Mostafa

      2017-01-01

      Background: Majority of parasitic infections in rodents have zoonotic importance. This study aimed to determine the frequency and intensity of intestinal protozoa infections of rodents including Meriones persicus, Mus musculus and, Cricetulus migratorius. Methods: This survey was conducted in Meshkin Shahr district in northwestern Iran from Mar. to Dec. of 2014. Intestinal samples of 204 rodents including M. persicus (n=117), M. musculus (n=63) and C. migratorius (n=24) were parasitologically examined. Formalin-ether concentration method was done for all of rodents stool samples and observed with light microscope. All of suspected cases were stained with trichorome staining Method. Cultivation in dichromate potassium 2.5% was carried out for all of coccidian positive samples. Acid fast and aniline blue staining methods were used for detecting of coccidian oocysts and intestinal microsporidial spores, respectively. Results: About 121(59.3%) of the caught rodents were generally infected with intestinal protozoa. Entamoeba muris 14(6.9%), Trichomonas muris 55(27.0%), Chilomastix betencourtti 17 (8.3%), Giardia muris 19(9.3%), Eimeria spp. 46(22.5%), Isospora spp. 4(2%) and Cryptosporidium spp. 1(0.5%) were found from the collected rodents. Microsporidian spores were identified in 63 (31%) out of the 204 collected rodents using aniline blue staining method. Conclusion: Since some of the infections are zoonotic importance thus, control of rodents can be decreased new cases of the parasitic zoonoses in humans. PMID:28979348

    16. an ecological study on rodents of natural vegetation and farm lands ...

      African Journals Online (AJOL)

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      habitat association of rodents was conducted in Siltie natural vegetation and nearby farmlands ... In each habitat type, one representative grid was selected for live trapping. In addition, rodents were also snap- trapped from these habitats. A total of 562 captures was made .... into seeds, leaves, roots, earthworms and arthro-.

    17. A test of five mechanisms of species coexistence between rodents in ...

      African Journals Online (AJOL)

      A test of five mechanisms of species coexistence between rodents in a southern African savanna. M.R. Perrin, B.P. Kotler. Abstract. The operation of five different mechanisms of species coexistence in a community of rodents was examined in a semi-arid Kalahari savanna in southern Africa. The two most common species ...

    18. Cone and seed traits of two Juniperus species influence roles of frugivores and scatter-hoarding rodents as seed dispersal agents

      Science.gov (United States)

      Dimitri, Lindsay A.; Longland, William S.; Vander Wall, Stephen B.

      2017-11-01

      Seed dispersal in Juniperus is generally attributed to frugivores that consume the berry-like female cones. Some juniper cones are fleshy and resinous such as those of western juniper (Juniperus occidentalis), while others are dry and leathery such as those of Utah juniper (J. osteosperma). Rodents have been recorded harvesting Juniperus seeds and cones but are mostly considered seed predators. Our study sought to determine if rodents play a role in dispersal of western and Utah juniper seeds. We documented rodent harvest of cones and seeds of the locally-occurring juniper species and the alternate (non-local) juniper species in removal experiments at a western juniper site in northeastern California and a Utah juniper site in western Nevada. Characteristics of western and Utah juniper cones appeared to influence removal, as cones from the local juniper species were preferred at both sites. Conversely, removal of local and non-local seeds was similar. Piñon mice (Peromyscus truei) were responsible for most removal of cones and seeds at both sites. We used radioactively labeled seeds to follow seed fate and found many of these seeds in scattered caches (western juniper: 415 seeds in 82 caches, 63.0% of seeds found; Utah juniper: 458 seeds in 127 caches, 39.5% of seeds found) most of which were attributed to piñon mice. We found little evidence of frugivores dispersing Utah juniper seeds, thus scatter-hoarding rodents appear to be the main dispersal agents. Western juniper cones were eaten by frugivores, and scatter-hoarding is a complimentary or secondary form of seed dispersal. Our results support the notion that Utah juniper has adapted to xeric environments by conserving water through the loss of fleshy fruits that attract frugivores and instead relies on scatter-hoarding rodents as effective dispersal agents.

    19. SUPLEMENTACIÓN CON PARED CELULAR Y CULTIVO DE LEVADURAS EN VACAS PRONTAS Y SU EFECTO SOBRE LA CALIDAD DEL CALOSTRO Y EL ESTADO INMUNOLÓGICO DE LAS TERNERAS

      Directory of Open Access Journals (Sweden)

      Carlos Campos-Granados

      2015-01-01

      Full Text Available El estudio fue realizado en una finca comercial ubicada en Santa Rosa de Oreamuno, Provincia de Cartago. Se utilizaron 30 vacas Jersey preparto y sus respectivas terneras, dis - tribuidas en un modelo irrestricto al azar, con 2 tratamientos de 15 repeticiones cada uno: el primero fue el control (no suplementado y el segundo se suplementó diariamente, a partir de los 21 días preparto, con 40 g de pared celular y cultivo de levaduras. Se cuantificó la concentra - ción de inmunoglobulinas totales en el calostro de las vacas en estudio, obteniéndose diferencias significativas (p0,05, obteniéndose valores promedio de 8,57±1,27 g.dl -1 y 8,24±1,26 g.dl -1 , para el grupo control y el suplementado, respectivamen - te. Se cuantificó la ganancia diaria de peso, el crecimiento semanal expresado como altura la cruz, el consumo diario de dieta sólida y la conversión alimenticia de las terneras durante las primeras 8 semanas, y no se encontraron dife - rencias significativas para ninguna de las varia - bles antes mencionadas (p>0,05, obteniéndose valores promedio de ganancia diaria de peso de 382,86±61,20 g y 410,94±51,22 g, de crecimien - to semanal de 1,45±0,33 cm y 1,70±0,31 cm, de consumo de dieta sólida de 985,17±8,51 g y 977,51±5,74 g, y de conversión alimenticia de 2,57±0,11 y 2,38±0,09, para el grupo control y el suplementado, respectivamente. Se concluye que la suplementación con pared celular y cultivo de levaduras tuvo efecto mejorador sobre la concen - tración de inmunoglobulinas totales en el calostro y un efecto mejorador en la salud de las terneras, reflejado en la menor incidencia de enfermedades respiratorias y del tracto digestivo.

    20. Caracterización mecánica y microestructural de aceros de baja activación candidatos como primera pared en los reactores de fusión por confinamiento magnético

      Directory of Open Access Journals (Sweden)

      Hernández, M. T.

      1996-04-01

      Full Text Available Currently, the design development of fusion reactors and the possible materials to use in them are being studied in parallel. One of the most critical problems in this research is the structural material selection for the first wall and blanket. The aim of the present work is to study three low activation alloys designed in Germany in which niobium has been substituted by tantalum or cerium. The mechanical results show that the alloys containing cerium are in the same order of the low activation materials known to date, but the tantalum doped alloy produces TaC3 precipitation that destabilizes the matrix and provokes large microstructural changes. This causes a decrease of the mechanical properties at about 600 °C. This fact makes this alloy unsuitable for the first wall on fusion reactors, because the working temperature is near 550 °C.

      Actualmente, se está estudiando de forma paralela al desarrollo del diseño de los reactores de fusión los posibles materiales a emplear en estos. Una de las cuestiones más críticas en esta investigación es la selección del material estructural a emplear como primera pared y envoltura. En el presente trabajo se estudian tres aleaciones de diseño alemán de baja activación, en las que se ha sustituido el niobio por tantalio o por cerio. Los resultados mecánicos muestran que las aleaciones, en las que se ha añadido cerio de forma controlada, están en la línea de las de baja activación existentes hasta ahora, pero la adición de tantalio presenta problemas al provocar una precipitación primaria y masiva de carburos TaC3 que desestabiliza la matriz y origina cambios microestructurales muy acusados. Así, ocurre un descenso en las propiedades mecánicas en torno a los 600 °C, que la incapacita para la aplicación como primera pared, ya que la temperatura de trabajo de ésta se halla en torno a los 550 °C.

    1. In vivo microCT imaging of rodent cerebral vasculature

      International Nuclear Information System (INIS)

      Seo, Youngho; Hasegawa, Bruce H; Hashimoto, Tomoki; Nuki, Yoshitsugu

      2008-01-01

      Computed tomography (CT) remains a critical diagnostic tool for evaluating patients with cerebrovascular disease, and the advent of specialized systems for imaging rodents has extended these techniques to small animal models of these diseases. We therefore have evaluated in vivo methods of imaging rat models of hemorrhagic stroke using a high resolution compact computed tomography ('microCT') system (FLEX(tm) X-O(tm), Gamma Medica-Ideas, Northridge, CA). For all in vivo studies, the head of the anesthetized rat was secured in a custom immobilization device for microCT imaging with 512 projections over 2 min at 60 kVp and 0.530 mA (I tube x t/rotation = 63.6 mAs). First, imaging without iodinated contrast was performed (a) to differentiate the effect of contrast agent in contrast-enhanced CT and (b) to examine the effectiveness of the immobilization device between two time points of CT acquisitions. Then, contrast-enhanced CT was performed with continuous administration of iopromide (300 mgI ml -1 at 1.2 ml min -1 ) to visualize aneurysms and other vascular formations in the carotid and cerebral arteries that may precede subarachnoid hemorrhage. The accuracy of registration between the noncontrast and contrast-enhanced CT images with the immobilization device was compared against the images aligned with normalized mutual information using FMRIB's linear image registration tool (FLIRT). Translations and rotations were examined between the FLIRT-aligned noncontrast CT image and the nonaligned noncontrast CT image. These two data sets demonstrated translational and rotational differences of less than 0.5 voxel (∼85 μm) and 0.5 deg., respectively. Noncontrast CT demonstrated a very small volume (0.1 ml) of femoral arterial blood introduced surgically into the rodent brain. Continuous administration of iopromide during the CT acquisition produced consistent vascular contrast in the reconstructed CT images. As a result, carotid arteries and major cerebral blood vessels

    2. In vivo microCT imaging of rodent cerebral vasculature

      Energy Technology Data Exchange (ETDEWEB)

      Seo, Youngho; Hasegawa, Bruce H [Center for Molecular and Functional Imaging, Department of Radiology, University of California, San Francisco, CA 94143 (United States); Hashimoto, Tomoki; Nuki, Yoshitsugu [Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA 94143 (United States)], E-mail: youngho.seo@radiology.ucsf.edu

      2008-04-07

      Computed tomography (CT) remains a critical diagnostic tool for evaluating patients with cerebrovascular disease, and the advent of specialized systems for imaging rodents has extended these techniques to small animal models of these diseases. We therefore have evaluated in vivo methods of imaging rat models of hemorrhagic stroke using a high resolution compact computed tomography ('microCT') system (FLEX(tm) X-O(tm), Gamma Medica-Ideas, Northridge, CA). For all in vivo studies, the head of the anesthetized rat was secured in a custom immobilization device for microCT imaging with 512 projections over 2 min at 60 kVp and 0.530 mA (I{sub tube} x t/rotation = 63.6 mAs). First, imaging without iodinated contrast was performed (a) to differentiate the effect of contrast agent in contrast-enhanced CT and (b) to examine the effectiveness of the immobilization device between two time points of CT acquisitions. Then, contrast-enhanced CT was performed with continuous administration of iopromide (300 mgI ml{sup -1} at 1.2 ml min{sup -1}) to visualize aneurysms and other vascular formations in the carotid and cerebral arteries that may precede subarachnoid hemorrhage. The accuracy of registration between the noncontrast and contrast-enhanced CT images with the immobilization device was compared against the images aligned with normalized mutual information using FMRIB's linear image registration tool (FLIRT). Translations and rotations were examined between the FLIRT-aligned noncontrast CT image and the nonaligned noncontrast CT image. These two data sets demonstrated translational and rotational differences of less than 0.5 voxel ({approx}85 {mu}m) and 0.5 deg., respectively. Noncontrast CT demonstrated a very small volume (0.1 ml) of femoral arterial blood introduced surgically into the rodent brain. Continuous administration of iopromide during the CT acquisition produced consistent vascular contrast in the reconstructed CT images. As a result, carotid

    3. Neurobiology of rodent self-grooming and its value for translational neuroscience.

      Science.gov (United States)

      Kalueff, Allan V; Stewart, Adam Michael; Song, Cai; Berridge, Kent C; Graybiel, Ann M; Fentress, John C

      2016-01-01

      Self-grooming is a complex innate behaviour with an evolutionarily conserved sequencing pattern and is one of the most frequently performed behavioural activities in rodents. In this Review, we discuss the neurobiology of rodent self-grooming, and we highlight studies of rodent models of neuropsychiatric disorders--including models of autism spectrum disorder and obsessive compulsive disorder--that have assessed self-grooming phenotypes. We suggest that rodent self-grooming may be a useful measure of repetitive behaviour in such models, and therefore of value to translational psychiatry. Assessment of rodent self-grooming may also be useful for understanding the neural circuits that are involved in complex sequential patterns of action.

    4. Normas percebidas por estudantes universitários de três carreiras, da área da saúde, sobre o uso de drogas entre seus pares Normas percibidas por estudiantes universitarios sobre el uso de drogas entre sus pares, en tres áreas académicas de la salud Perceived norms among university students of three health courses for drug use among peers

      Directory of Open Access Journals (Sweden)

      Ana Maria Pimenta Carvalho

      2009-01-01

      Full Text Available O presente estudo abordou alunos de segundo e terceiro anos de três cursos da área da saúde tendo como objetivos identificar a estimativa do uso de drogas por estudantes universitários (norma percebida, a frequência de uso na presente amostra (norma real, comparar as estimativas com a frequência e identificar condições nas quais as drogas são usadas. Os estudantes superestimaram o uso, por seus pares, de tabaco, maconha e cocaína, na vida e nos últimos 12 meses. O álcool foi exceção. A porcentagem de uso relatada pelos estudantes da amostra e a estimativa do uso por estudantes em geral foram muito próximas. As substâncias são mais consumidas em festas e na companhia de colegas da universidade. Os dados foram interpretados à luz da Teoria das Normas Sociais, da Atribuição de Causalidade e da Normalização.El presente estudio tuvo como participantes a los alumnos del segundo e tercero año de tres cursos académicos de la Salud; el objetivo fue identificar la estimativa del uso de drogas (norma percibida, la frecuencia del uso (norma real, comparar las estimativas con la frecuencia y las condiciones en las cuales se usan las drogas. Se encontró que los estudiantes sobreestimaron el uso de sus pares en lo que se refiere al uso de tabaco, marihuana y cocaína, en alguna vez en la vida y el los últimos 12 meses. El alcohol fue la excepción, ya que el porcentaje de uso y la estimativa estuvieron muy próximos. Las sustancias son consumidas con mayor frecuencia en fiestas y en compañía de sus pares universitarios. Los datos fueran interpretados según el marco la Teoría de las Normas Sociales, de la Atribución de Causalidad y de la Normalización.The present study interviewed second- and third-year students of three health courses to identify university students' estimates for drug use (perceived norm, the rate of drug use among the subjects (real norm; compare the estimates with the actual frequency; and identify in what

    5. Normas percibidas por los estudiantes universitarios hondureños acerca de sus pares y el uso de tabaco, alcohol, marihuana y cocaína Normas percebidas pelos estudantes universitários hondurenhos sobre os pares e o uso de tabaco, álcool, maconha e cocaína Perceived norms among honduran university students about peers and tobacco, alcohol, marijuana and cocaine use

      Directory of Open Access Journals (Sweden)

      Syntia Dinora Santos Figueroa

      2009-01-01

      Full Text Available El propósito del presente estudio fue estimar la diferencia entre las normas percibidas sobre el uso de drogas por los pares y el uso real informado por estudiantes universitarios, entre 18 a 24 años, del segundo y tercer año en el área de Educación. La teoría de las Normas Sociales fue usada como marco referencial. 286 estudiantes participaron en el estudio, el 67% expresó haber consumido alcohol al menos una vez en la vida y el 28% declaró consumirlo diariamente. Los estudiantes percibieron que 62% de sus compañeros consumen tabaco y el 63% alcohol. El estándar percibido de consumo de drogas fue ligeramente más alto entre las mujeres que en los hombres. Se concluye que los resultados indican una sobreestimación al compararse el estándar percibido con el consumo informado de tabaco y alcohol así como de marihuana y cocaína.O objetivo do presente estudo foi estimar a diferença entre as normas percebidas sobre o uso de drogas pelos pares e o próprio uso em estudantes universitários, entre 18 e 24 anos, do segundo e terceiro ano da área de educação. A teoria das Normas Sociais foi usada como marco referencial. Participaram do estudo 286 estudantes, sendo que 67% declararam ter consumido álcool ao menos uma vez na vida e 28%, diariamente. Os estudantes estimaram que 62% dos pares consomem tabaco e 63%, álcool. A norma percebida para o consumo de drogas foi ligeiramente mais alta em mulheres do que em homens. Como conclusão os resultados indicaram hiperestimativa ao se comparar a norma percebida com o próprio consumo, em relação ao tabaco, ao álcool, à maconha e à cocaína.The purpose of this study was to assess the difference between perceived norms and peers' drug use among sophomore and junior university students (from the field of education aged 18 to 24 years. The Social Norms Theory was used as the theoretical framework. In total, 286 students participated in the study, 67% of which reported having consumed

    6. Alternative conceptions of memory consolidation and the role of the hippocampus at the systems level in rodents.

      Science.gov (United States)

      Sutherland, R J; Lehmann, H

      2011-06-01

      We discuss very recent experiments with rodents addressing the idea that long-term memories initially depending on the hippocampus, over a prolonged period, become independent of it. No unambiguous recent evidence exists to substantiate that this occurs. Most experiments find that recent and remote memories are equally affected by hippocampus damage. Nearly all experiments that report spared remote memories suffer from two problems: retrieval could be based upon substantial regions of spared hippocampus and recent memory is tested at intervals that are of the same order of magnitude as cellular consolidation. Accordingly, we point the way beyond systems consolidation theories, both the Standard Model of Consolidation and the Multiple Trace Theory, and propose a simpler multiple storage site hypothesis. On this view, with event reiterations, different memory representations are independently established in multiple networks. Many detailed memories always depend on the hippocampus; the others may be established and maintained independently. Copyright © 2011 Elsevier Ltd. All rights reserved.

    7. Helminth Infections of Rodents and Their Zoonotic Importance in Boyer-Ahmad District, Southwestern Iran.

      Science.gov (United States)

      Ranjbar, Mohammad Javad; Sarkari, Bahador; Mowlavi, Gholam Reza; Seifollahi, Zeinab; Moshfe, Abdolali; Abdolahi Khabisi, Samaneh; Mobedi, Iraj

      2017-01-01

      Rodents are considered as reservoirs of various zoonotic diseases including helminthic infections. The current study aimed to evaluate the prevalence of helminth infections in rodents, in Boyer-Ahmad district, Southwestern Iran. Overall, 52 rodents were captured from various areas of the district by Sherman live traps. The animals were then euthanized and dissected. During necropsy, each organ was examined macroscopically for presence of any cyst or visible parasite. The gastrointestinal tract was removed and their contents were evaluated for larva or adult worms. Trichinella larvae in the rodents' muscles were investigated by both digestion and pathological methods. Twenty-eight (53.8%) of the trapped rodents were male. The rodents were including 25 (48.1%) Meriones persicus , 1(1.9%) Calomyscus bailwardi , 1 (1.9%) Arvicola terresterris , 7 (13.5%) Rattus rattus , 8 (15.4%) R. norvegicus , and 10 (19.2%) Apodemus sylvaticus . Of them, 38 (73.0%) were infected with at least one helminth. Collected rodents were infected with Hymenolepis diminuta (50%), Hymenolepis nana fraterna (28.8%), Skrjabinotaenia sp. (15.4%), Anoplocephalidae sp. (15.4%), Cysticercus fasciolaris (5.8%), Trichuris muris (36.5%), Aspiculuris tetraptera (15.4%), Syphacia sp. (5.7%), Rictularia sp. (15.4%), Trichostrongylus sp. (3.8%), and Gongylonema sp. (3.8%). M. persicus was the most (84%) infected rodent, yet the differences between rodent genus and helminth infectivity were not statistically significant ( P >0.05). The rodents in Boyer-Ahmad district are infected with different helminths infections that some of them are recognized as threat to human health.

    8. Behavioral effects of developmental methylmercury drinking water exposure in rodents.

      Science.gov (United States)

      Bisen-Hersh, Emily B; Farina, Marcelo; Barbosa, Fernando; Rocha, Joao B T; Aschner, Michael

      2014-04-01

      Early methylmercury (MeHg) exposure can have long-lasting consequences likely arising from impaired developmental processes, the outcome of which has been exposed in several longitudinal studies of affected populations. Given the large number of newborns at an increased risk of learning disabilities associated with in utero MeHg exposure, it is important to study neurobehavioral alterations using ecologically valid and physiologically relevant models. This review highlights the benefits of using the MeHg drinking water exposure paradigm and outlines behavioral outcomes arising from this procedure in rodents. Combination treatments that exacerbate or ameliorate MeHg-induced effects, and possible molecular mechanisms underlying behavioral impairment are also discussed. Copyright © 2013 Elsevier GmbH. All rights reserved.

    9. Transformation of the rodent malaria parasite Plasmodium chabaudi.

      Science.gov (United States)

      Spence, Philip J; Cunningham, Deirdre; Jarra, William; Lawton, Jennifer; Langhorne, Jean; Thompson, Joanne

      2011-04-01

      The rodent malaria parasite Plasmodium chabaudi chabaudi shares many features with human malaria species, including P. falciparum, and is the in vivo model of choice for many aspects of malaria research in the mammalian host, from sequestration of parasitized erythrocytes, to antigenic variation and host immunity and immunopathology. This protocol describes an optimized method for the transformation of mature blood-stage P.c. chabaudi and a description of a vector that targets efficient, single crossover integration into the P.c. chabaudi genome. Transformed lines are reproducibly generated and selected within 14-20 d, and show stable long-term protein expression even in the absence of drug selection. This protocol, therefore, provides the scientific community with a robust and reproducible method to generate transformed P.c. chabaudi parasites expressing fluorescent, bioluminescent and model antigens that can be used in vivo to dissect many of the fundamental principles of malaria infection.

    10. Rodent communities in the sub-polar Ural mountains

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      Berdyugin, K. I.

      2004-12-01

      Full Text Available Distribution of the rodent communities in the Sub-polar Urals is analysed. This part of the range, between 64° and 66°N, includes the highest peaks, is very scarcely settled and has been rarely studied. However, the area is interesting for biogeography, being a border zone separating European and Siberian lowland faunas. Comparison of results with those from expeditions undertaken in 1927 and in 1972, allows to evaluate changing trends in the local rodent communities, and to relate these trends to changes in the environmental conditions. The results help to emphasize the barrier role played by Sub-polar Urals for the species of rodents inhabiting both sides of the range, and also show the shifting of southern rodent forms northwards, or the moving upwards of other lowland species. This could be seen as an additional evidence of current climate warming trends.

      [fr]
      On analyse la répartition des communautés de rongeurs dans les Durais Subpolaires, une section de la chaîne comprise entre les 64° et les 66° de latitude N. Cette partie est très peu peuplée, elle possède les pics les plus hauts de la chaîne et a été rarement étudiée. Il s'agit d'une région intéressante, car c'est la frontière entre les plaines européennes et les plaines orientales de la Sibérie. En comparant les observations effectuées en 1927 et en 1972 avec celles des dernières années, on peut voir les tendances de changement des groupements de rongeurs de la région, et les interpréter en fonction des changements dans l'environnement. Les résultats permettent de mieux comprendre le rôle de barrière qui jouent les Durais Subpolaires pour les espèces de rongeurs situées d'un coté et d'autre de la chaîne. Aussi, ils permettent de verifier le déplacement vers le nord deformes méridionales et l'élévation en altitude d'autres, ce qui pourrait être vu comme une preuve additionnelle de la tendance au réchauffement global.
      [es]
      Se

    11. Transmission of Guanarito and Pirital Viruses among Wild Rodents, Venezuela

      Science.gov (United States)

      Milazzo, Mary L.; Cajimat, Maria N.B.; Duno, Gloria; Duno, Freddy; Utrera, Antonio

      2011-01-01

      Samples from rodents captured on a farm in Venezuela in February 1997 were tested for arenavirus, antibody against Guanarito virus (GTOV), and antibody against Pirital virus (PIRV). Thirty-one (48.4%) of 64 short-tailed cane mice (Zygodontomys brevicauda) were infected with GTOV, 1 Alston’s cotton rat (Sigmodon alstoni) was infected with GTOV, and 36 (64.3%) of 56 other Alston’s cotton rats were infected with PIRV. The results of analyses of field and laboratory data suggested that horizontal transmission is the dominant mode of GTOV transmission in Z. brevicauda mice and that vertical transmission is an important mode of PIRV transmission in S. alstoni rats. The results also suggested that bodily secretions and excretions from most GTOV-infected short-tailed cane mice and most PIRV-infected Alston’s cotton rats may transmit the viruses to humans. PMID:22172205

    12. Nonhuman gamblers: lessons from rodents, primates, and robots

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      Fabio ePaglieri

      2014-02-01

      Full Text Available The search for neuronal and psychological underpinnings of pathological gambling in humans would benefit from investigating related phenomena also outside of our species. In this paper, we present a survey of studies in three widely different populations of agents, namely rodents, non-human primates, and robots. Each of these populations offer valuable and complementary insights on the topic, as the literature demonstrates. In addition, we highlight the deep and complex connections between relevant results across these different areas of research (i.e., cognitive and computational neuroscience, neuroethology, cognitive primatology, neuropsychiatry, evolutionary robotics, to make the case for a greater degree of methodological integration in future studies on pathological gambling.

    13. Modelling the emergence of rodent filial huddling from physiological huddling

      Science.gov (United States)

      Wilson, Stuart P.

      2017-11-01

      Huddling behaviour in neonatal rodents reduces the metabolic costs of physiological thermoregulation. However, animals continue to huddle into adulthood, at ambient temperatures where they are able to sustain a basal metabolism in isolation from the huddle. This `filial huddling' in older animals is known to be guided by olfactory rather than thermal cues. The present study aimed to test whether thermally rewarding contacts between young mice, experienced when thermogenesis in brown adipose fat tissue (BAT) is highest, could give rise to olfactory preferences that persist as filial huddling interactions in adults. To this end, a simple model was constructed to fit existing data on the development of mouse thermal physiology and behaviour. The form of the model that emerged yields a remarkable explanation for filial huddling; associative learning maintains huddling into adulthood via processes that reduce thermodynamic entropy from BAT metabolism and increase information about social ordering among littermates.

    14. Identification of rodent homologs of hepatitis C virus and pegiviruses

      DEFF Research Database (Denmark)

      Kapoor, Amit; Simmonds, Peter; Scheel, Troels K H

      2013-01-01

      UNLABELLED: Hepatitis C virus (HCV) and human pegivirus (HPgV or GB virus C) are globally distributed and infect 2 to 5% of the human population. The lack of tractable-animal models for these viruses, in particular for HCV, has hampered the study of infection, transmission, virulence, immunity...... into the origins of human infections and enhances our ability to study their pathogenesis and explore preventive and therapeutic interventions. Horses are the only reported host of nonprimate homologs of hepatitis C virus (HCV). Here, we report the discovery of HCV-like viruses in wild rodents. The majority of HCV...... of small-animal models for HCV, the most common infectious cause of liver failure and hepatocellular carcinoma after hepatitis B virus, and help to explore the health relevance of the highly prevalent human pegiviruses....

    15. Morphological evolution, ecological diversification and climate change in rodents.

      Science.gov (United States)

      Renaud, Sabrina; Michaux, Jacques; Schmidt, Daniela N; Aguilar, Jean-Pierre; Mein, Pierre; Auffray, Jean-Christophe

      2005-03-22

      Among rodents, the lineage from Progonomys hispanicus to Stephanomys documents a case of increasing size and dental specialization during an approximately 9 Myr time-interval. On the contrary, some contemporaneous generalist lineages like Apodemus show a limited morphological evolution. Dental shape can be related to diet and can be used to assess the ecological changes along the lineages. Consequently, size and shape of the first upper molar were measured in order to quantify the patterns of morphological evolution along both lineages and compare them to environmental trends. Climatic changes do not have a direct influence on evolution, but they open new ecological opportunities by changing vegetation and allow the evolution of a specialist like Stephanomys. On the other hand, environmental changes are not dramatic enough to destroy the habitat of a long-term generalist like Apodemus. Hence, our results exemplify a case of an influence of climate on the evolution of specialist species, although a generalist species may persist without change.

    16. Fellow travellers: Working memory and mental time travel in rodents.

      Science.gov (United States)

      Dere, Ekrem; Dere, Dorothea; de Souza Silva, Maria Angelica; Huston, Joseph P; Zlomuzica, Armin

      2017-03-19

      The impairment of mental time travel is a severe cognitive symptom in patients with brain lesions and a number of neuropsychiatric disorders. Whether animals are also able to mentally travel in time both forward and backward is still a matter of debate. In this regard, we have proposed a continuum of mental time travel abilities across different animal species, with humans being the species with the ability to perform most sophisticated forms of mental time travel. In this review and perspective article, we delineate a novel approach to understand the evolution, characteristics and function of human and animal mental time travel. Furthermore, we propose a novel approach to measure mental time travel in rodents in a comprehensive manner using a test battery composed of well-validated and easy applicable tests. Copyright © 2017. Published by Elsevier B.V.

    17. Central melanopsin projections in the diurnal rodent, Arvicanthis niloticus

      Directory of Open Access Journals (Sweden)

      Jennifer Lou Langel

      2015-07-01

      Full Text Available The direct effects of photic stimuli on behavior are very different in diurnal and nocturnal species, as light stimulates an increase in activity in the former and a decrease in the latter. Studies of nocturnal mice have implicated a select population of retinal ganglion cells that are intrinsically photosensitive (ipRGCs in mediation of these acute responses to light. ipRGCs are photosensitive due to the expression of the photopigment melanopsin; these cells use glutamate and pituitary adenylate cyclase-activating polypeptide (PACAP as neurotransmitters. PACAP is useful for the study of central ipRGC projections because, in the retina, it is found exclusively within melanopsin cells. Little is known about the central projections of ipRGCs in diurnal species. Here, we first characterized these cells in the retina of the diurnal Nile grass rat using immunohistochemistry (IHC. The same basic subtypes of melanopsin cells that have been described in other mammals were present, but nearly 25% of them were displaced, primarily in its superior region. PACAP was present in 87.7% of all melanopsin cells, while 97.4% of PACAP cells contained melanopsin. We then investigated central projections of ipRGCs by examining the distribution of immunoreactive PACAP fibers in intact and enucleated animals. This revealed evidence that these cells project to the suprachiasmatic nucleus, lateral geniculate nucleus (LGN, pretectum and superior colliculus. This distribution was confirmed with injections of cholera toxin subunit β coupled with Alexa Fluor 488 in one eye and Alexa Flour 594 in the other, combined with IHC staining of PACAP. These studies also revealed that the ventral and dorsal LGN and the caudal olivary pretectal nucleus receive less innervation from ipRGCs than that reported in nocturnal rodents. Overall, these data suggest that although ipRGCs and their projections are very similar in diurnal and nocturnal rodents, they may not be identical.

    18. Arctic Small Rodents Have Diverse Diets and Flexible Food Selection.

      Directory of Open Access Journals (Sweden)

      Eeva M Soininen

      Full Text Available The ecology of small rodent food selection is poorly understood, as mammalian herbivore food selection theory has mainly been developed by studying ungulates. Especially, the effect of food availability on food selection in natural habitats where a range of food items are available is unknown. We studied diets and selectivity of grey-sided voles (Myodes rufocanus and tundra voles (Microtus oeconomus, key herbivores in European tundra ecosystems, using DNA metabarcoding, a novel method enabling taxonomically detailed diet studies. In order to cover the range of food availabilities present in the wild, we employed a large-scale study design for sampling data on food availability and vole diets. Both vole species had ingested a range of plant species and selected particularly forbs and grasses. Grey-sided voles also selected ericoid shrubs and tundra voles willows. Availability of a food item rarely affected its utilization directly, although seasonal changes of diets and selection suggest that these are positively correlated with availability. Moreover, diets and selectivity were affected by availability of alternative food items. These results show that the focal sub-arctic voles have diverse diets and flexible food preferences and rarely compensate low availability of a food item with increased searching effort. Diet diversity itself is likely to be an important trait and has previously been underrated owing to methodological constraints. We suggest that the roles of alternative food item availability and search time limitations for small rodent feeding ecology should be investigated.Annotated Checklist of the Panarctic Flora (PAF, Vascular plants. Available at: http://nhm2.uio.no/paf/, accessed 15.6.2012.

    19. Osseointegration of biochemically modified implants in an osteoporosis rodent model

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      B Stadlinger

      2013-07-01

      Full Text Available The present study examined the impact of implant surface modifications on osseointegration in an osteoporotic rodent model. Sandblasted, acid-etched titanium implants were either used directly (control or were further modified by surface conditioning with NaOH or by coating with one of the following active agents: collagen/chondroitin sulphate, simvastatin, or zoledronic acid. Control and modified implants were inserted into the proximal tibia of aged ovariectomised (OVX osteoporotic rats (n = 32/group. In addition, aged oestrogen competent animals received either control or NaOH conditioned implants. Animals were sacrificed 2 and 4 weeks post-implantation. The excised tibiae were utilised for biomechanical and morphometric readouts (n = 8/group/readout. Biomechanical testing revealed at both time points dramatically reduced osseointegration in the tibia of oestrogen deprived osteoporotic animals compared to intact controls irrespective of NaOH exposure. Consistently, histomorphometric and microCT analyses demonstrated diminished bone-implant contact (BIC, peri-implant bone area (BA, bone volume/tissue volume (BV/TV and bone-mineral density (BMD in OVX animals. Surface coating with collagen/chondroitin sulphate had no detectable impact on osseointegration. Interestingly, statin coating resulted in a transient increase in BIC 2 weeks post-implantation; which, however, did not correspond to improvement of biomechanical readouts. Local exposure to zoledronic acid increased BIC, BA, BV/TV and BMD at 4 weeks. Yet this translated only into a non-significant improvement of biomechanical properties. In conclusion, this study presents a rodent model mimicking severely osteoporotic bone. Contrary to the other bioactive agents, locally released zoledronic acid had a positive impact on osseointegration albeit to a lesser extent than reported in less challenging models.

    20. Latin American Legislative Politics: A Survey of Peer-Reviewed Publications in English La política legislativa latinoamericana: un estudio de publicaciones en inglés evaluadas por pares

      Directory of Open Access Journals (Sweden)

      Eduardo Alemán

      2013-01-01

      Full Text Available This study discusses basic trends in articles on legislative politics in Latin America published in twelve journals between 2000 and 2010. It examines the distribution of the articles over time and by journal, the authors’ institutional affiliations and patterns of collaboration, the frequency with which various countries are studied, and common approaches and topics. The articles in this set are all peer-reviewed and published in English.Este estudio analiza las tendencias principales en artículos de política legislativa en América Latina publicados en doce revistas entre 2000 y 2010. Examina la distribución de los artículos a través del tiempo y de las revistas académicas, las afiliaciones institucionales de los autores y sus patrones de colaboración, la frecuencia con la cual varios países son estudiados, y los enfoques y temas tratados. Los artículos examinados han sido evaluados por pares y publicados en inglés.

    1. Reconstrucción de canto interno y pared lateral nasal con colgajo zigomático de mejilla Reconstructing soft tissue defects at the medial canthus and sidewalls of the nose with cheek zygomatic flap

      Directory of Open Access Journals (Sweden)

      J. de Abullarade

      2009-06-01

      Full Text Available En la reconstrucción del canto interno palpebral y de la pared lateral nasal es importante la continuidad del color, de la textura y del grosor del tejido que vamos a reemplazar. El colgajo zigomático de mejilla es un colgajo de patrón axial que, cuando se diseña adecuadamente, puede seguir los contornos naturales de la cara, como el pliegue nasolabial y el borde del párpado inferior, logrando un reemplazo casi exacto de la calidad de la piel existente y con una reparación realizada en un solo tiempo quirúrgico.In it's important to keep the continuity of colour, texture and thickness of the tissue in a reconstructed nose. The zigomatic cheek flap is an axial pattern flap that, when is properly designed, can follow the natural existing contour lines such as the nasolabial fold and the lower eyelid border. It gets an almost exactly replacement of matching skin quality, in one surgical stage.

    2. The Programming of the Social Brain by Stress During Childhood and Adolescence: From Rodents to Humans.

      Science.gov (United States)

      Tzanoulinou, Stamatina; Sandi, Carmen

      2017-01-01

      The quality and quantity of social experience is fundamental to an individual's health and well-being. Early life stress is known to be an important factor in the programming of the social brain that exerts detrimental effects on social behaviors. The peri-adolescent period, comprising late childhood and adolescence, represents a critical developmental window with regard to the programming effects of stress on the social brain. Here, we discuss social behavior and the physiological and neurobiological consequences of stress during peri-adolescence in the context of rodent paradigms that model human adversity, including social neglect and isolation, social abuse, and exposure to fearful experiences. Furthermore, we discuss peri-adolescent stress as a potent component that influences the social behaviors of individuals in close contact with stressed individuals and that can also influence future generations. We also discuss the temporal dynamics programmed by stress on the social brain and debate whether social behavior alterations are adaptive or maladaptive. By revising the existing literature and defining open questions, we aim to expand the framework in which interactions among peri-adolescent stress, the social brain, and behavior can be better conceptualized.

    3. Hepatozoon spp. infections in wild rodents in an area of endemic canine hepatozoonosis in southeastern Brazil.

      Science.gov (United States)

      Demoner, Larissa de Castro; Magro, Natalia Mizuhira; da Silva, Maria Regina Lucas; de Paula Antunes, João Marcelo Azevedo; Calabuig, Cecilia Irene Pérez; O'Dwyer, Lucia Helena

      2016-07-01

      Hepatozoon canis is a tick-borne parasite that occurs worldwide. In rural areas of Brazil, H. canis vectors remain unknown, which has led to speculation about alternative routes of transmission. Small rodents can play a role in the transmission (via predation) of Hepatozoon americanum, which led us to question whether predation might be an alternative mode of transmission for H. canis. Thus, this study investigated whether Hepatozoon spp. are present in wild small rodents in forest fragments that surround rural areas in Botucatu County, São Paulo, Brazil, where canine hepatozoonosis is endemic. The study included blood samples from 158 dogs, which were screened by microscopy and molecular analysis. Blood samples and tissues from 67 rodents were obtained for histopathology and molecular detection. The prevalence of H. canis was high (66.45%) in dogs from rural areas of Botucatu, São Paulo, Brazil. The molecular analysis showed that wild rodent species in Brazil were infected with Hepatozoon spp. other than H. canis. Therefore, although the hypothesis that sylvatic rodents act as reservoirs for H. canis was not supported, the presence of monozoic cysts in the rodents suggests that, in addition to intermediate hosts, wild small rodents in Brazil might act as paratenic hosts of Hepatozoon spp. because they harbor infective stages for intermediate host predators. Copyright © 2016 Elsevier GmbH. All rights reserved.

    4. Research Note. Occurrence of gastrointestinal helminths in commensal rodents from Tabasco, Mexico

      Directory of Open Access Journals (Sweden)

      Cigarroa-Toledo N.

      2017-06-01

      Full Text Available The aim of this study was to determine the prevalence and species composition of helminths in commensal rodents captured inside private residences in the city of Villahermosa in Tabasco, Mexico. Trapping was performed at each house for three consecutive nights from October to December 2015. Fifty commensal rodents were captured: 23 Rattus norvegicus, 16 Mus musculus and 11 Rattus rattus. Rodents were transported alive to the laboratory and held in cages until they defecated. Feces were analyzed for helminth eggs using the Sheather’s flotation technique. The overall prevalence of helminths in rodents was 60 %: R. norvegicus was more likely to be parasitized (87.0 % than R. rattus (63.6 % and M. musculus (18.8 %. Eggs from at least 13 species of helminths were identified: Hymenolepis diminuta, Rodentolepis nana, Moniliformis moniliformis, Heligmosomoides polygyrus, Heterakis spumosa, Mastophorus muris, Nippostrongylus brasiliensis, Strongyloides ratti, Syphacia obvelata, Syphacia muris, Toxocara sp., Trichosomoides crassicauda, and Trichuris muris. This is the first study to report the presence of H. polygyrus, S. ratti and T. crassicauda in commensal rodents in Mexico. In conclusion, our results suggest that helminths commonly infect commensal rodents in Villahermosa and therefore rodents present a health risk to inhabitants in this region.

    5. Sleep in the Cape Mole Rat: A Short-Sleeping Subterranean Rodent.

      Science.gov (United States)

      Kruger, Jean-Leigh; Gravett, Nadine; Bhagwandin, Adhil; Bennett, Nigel C; Archer, Elizabeth K; Manger, Paul R

      2016-01-01

      The Cape mole rat Georychus capensis is a solitary subterranean rodent found in the western and southern Cape of South Africa. This approximately 200-gram bathyergid rodent shows a nocturnal circadian rhythm, but sleep in this species is yet to be investigated. Using telemetric recordings of the electroencephalogram (EEG) and electromyogram (EMG) in conjunction with video recordings, we were able to show that the Cape mole rat, like all other rodents, has sleep periods composed of both rapid eye movement (REM) and slow-wave (non-REM) sleep. These mole rats spent on average 15.4 h awake, 7.1 h in non-REM sleep and 1.5 h in REM sleep each day. Cape mole rats sleep substantially less than other similarly sized terrestrial rodents but have a similar percentage of total sleep time occupied by REM sleep. In addition, the duration of both non-REM and REM sleep episodes was markedly shorter in the Cape mole rat than has been observed in terrestrial rodents. Interestingly, these features (total sleep time and episode duration) are similar to those observed in another subterranean bathyergid mole rat, i.e. Fukomys mechowii. Thus, there appears to be a bathyergid type of sleep amongst the rodents that may be related to their environment and the effect of this on their circadian rhythm. Investigating further species of bathyergid mole rats may fully define the emerging picture of sleep in these subterranean African rodents. © 2016 S. Karger AG, Basel.

    6. Domestic cats and dogs create a landscape of fear for pest rodents around rural homesteads.

      Directory of Open Access Journals (Sweden)

      Themb'alilahlwa A M Mahlaba

      Full Text Available Using domestic predators such as cats to control rodent pest problems around farms and homesteads is common across the world. However, practical scientific evidence on the impact of such biological control in agricultural settings is often lacking. We tested whether the presence of domestic cats and/or dogs in rural homesteads would affect the foraging behaviour of pest rodents. We estimated giving up densities (GUDs from established feeding patches and estimated relative rodent activity using tracking tiles at 40 homesteads across four agricultural communities. We found that the presence of cats and dogs at the same homestead significantly reduced activity and increased GUDs (i.e. increased perception of foraging cost of pest rodent species. However, if only cats or dogs alone were present at the homestead there was no observed difference in rodent foraging activity in comparison to homesteads with no cats or dogs. Our results suggest that pest rodent activity can be discouraged through the presence of domestic predators. When different types of predator are present together they likely create a heightened landscape of fear for foraging rodents.

    7. Gender differences in the induction of chromosomal aberrations and gene mutations in rodent germ cells

      International Nuclear Information System (INIS)

      Adler, Ilse-Dore; Carere, Angelo; Eichenlaub-Ritter, Ursula; Pacchierotti, Francesca

      2007-01-01

      Germ cell mutagenicity testing provides experimental data to quantify genetic risk for exposed human populations. The majority of tests are performed with exposure of males, and female data are relatively rare. The reason for this paucity lies in the differences between male and female germ cell biology. Male germ cells are produced throughout reproductive life and all developmental stages can be ascertained by appropriate breeding schemes. In contrast, the female germ cell pool is limited, meiosis begins during embryogenesis and oocytes are arrested over long periods of time until maturation processes start for small numbers of oocytes during the oestrus cycle in mature females. The literature data are reviewed to point out possible gender differences of germ cells to exogenous agents such as chemicals or ionizing radiation. From the limited information, it can be concluded that male germ cells are more sensitive than female germ cells to the induction of chromosomal aberrations and gene mutations. However, exceptions are described which shed doubt on the extrapolation of experimental data from male rodents to the genetic risk of the human population. Furthermore, the female genome may be more sensitive to mutation induction during peri-conceptional stages compared to the male genome of the zygote. With few exceptions, germ cell experiments have been carried out under high acute exposure to optimize the effects and to compensate for the limited sample size in animal experiments. Human exposure to environmental agents, on the other hand, is usually chronic and involves low doses. Under these conditions, gender differences may become apparent that have not been studied so far. Additionally, data are reviewed that suggest a false impression of safety when responses are negative under high acute exposure of male rodents while a mutational response is induced by low chronic exposure. The classical (morphological) germ cell mutation tests are not performed anymore

    8. Biospecimen Retrieval from NASA's Rodent Research-1: Maximizing Science Return from Flight Missions

      Science.gov (United States)

      Choi, Sungshin Y.; Chen, Yi-Chun; Reyes, America; Verma, Vandana; Dinh, Marie; Globus, Ruth K.

      2016-01-01

      Rodent Research (RR)-1 was conducted to validate flight hardware, operations, and science capabilities that were developed to support long duration missions on the International Space Station. After 37 days in microgravity twenty mice were euthanized and frozen on orbit. Upon return to Earth the carcasses were dissected and yielded 32 different types of tissues from each mouse and over 3200 tissue aliquots. Many tissues were distributed to the Space Life and Physical Sciences (SLPS) Biospecimen Sharing Program (BSP) Principal Investigators (PIs) through the Ames Life Science Data Archive (ALSDA). A second round of dissections was performed to collect additional tissues from the remaining carcasses thawed for a second time for additional BSP PIs. Tissues retrieved included vaginal walls, aorta, pelvis, brown adipose tissue, tail, spine and forearms. Although the analyses are still in progress, some of the PIs have reported that the quality of the tissues was acceptable for their study. In a separate experiment we tested the RNA quality of the tissues that were dissected from frozen carcasses that were subjected to euthanasia, freezing, first and second thaw dissections. Timelines simulated the on-orbit RR-1 procedures to assess the quality of the tissues retrieved from the second thaw dissections. We analyzed the RIN values of select tissues including kidney, brain, white adipose tissue (WAT) and brown adipose tissue (BAT). Overall the RIN values from the second thaw were lower compared to those from the first by about a half unit; however, the tissues yielded RNA that are acceptable quality for some quantitative gene expression assays. Interestingly, RIN values of brain tissues were 8.4+/-0.6 and 7.9+/-0.7 from first and second round dissections, respectively (n5). Kidney and WAT yielded RIN values less than 8 but they can still be used for qPCR. BAT yielded higher quality RNA (8.2+/-0.5) than WAT (5.2+/-20.9), possibly due to the high fat content. Together, these

    9. Helminth Infections of Rodents and Their Zoonotic Importance in Boyer-Ahmad District, Southwestern Iran

      Directory of Open Access Journals (Sweden)

      Mohammad Javad RANJBAR

      2017-12-01

      Full Text Available AbstractBackground: Rodents are considered as reservoirs of various zoonotic diseases including helminthic infections. The current study aimed to evaluate the prevalence of helminth infections in rodents, in Boyer-Ahmad district, Southwestern Iran.Methods: Overall, 52 rodents were captured from various areas of the district by Sherman live traps. The animals were then euthanized and dissected. During necropsy, each organ was examined macroscopically for presence of any cyst or visible parasite. The gastrointestinal tract was removed and their contents were evaluated for larva or adult worms. Trichinella larvae in the rodents’ muscles were investigated by both digestion and pathological methods.Results: Twenty-eight (53.8% of the trapped rodents were male. The rodents were including 25 (48.1% Meriones persicus, 1(1.9% Calomyscus bailwardi, 1 (1.9% Arvicola terresterris, 7 (13.5% Rattus rattus, 8 (15.4% R. norvegicus, and 10 (19.2% Apodemus sylvaticus. Of them, 38 (73.0% were infected with at least one helminth. Collected rodents were infected with Hymenolepis diminuta (50%, Hymenolepis nana fraterna (28.8%, Skrjabinotaenia sp. (15.4%, Anoplocephalidae sp. (15.4%, Cysticercus fasciolaris (5.8%, Trichuris muris (36.5%, Aspiculuris tetraptera (15.4%, Syphacia sp. (5.7%, Rictularia sp. (15.4%, Trichostrongylus sp. (3.8%, and Gongylonema sp. (3.8%. M. persicus was the most (84% infected rodent, yet the differences between rodent genus and helminth infectivity were not statistically significant (P>0.05.Conclusion: The rodents in Boyer-Ahmad district are infected with different helminths infections that some of them are recognized as threat to human health.

    10. Correlates of Recent Declines of Rodents in Northern and Southern Australia: Habitat Structure Is Critical.

      Directory of Open Access Journals (Sweden)

      Michael J Lawes

      Full Text Available Australia has experienced dramatic declines and extinctions of its native rodent species over the last 200 years, particularly in southern Australia. In the tropical savanna of northern Australia significant declines have occurred only in recent decades. The later onset of these declines suggests that the causes may differ from earlier declines in the south. We examine potential regional effects (northern versus southern Australia on biological and ecological correlates of range decline in Australian rodents. We demonstrate that rodent declines have been greater in the south than in the tropical north, are strongly influenced by phylogeny, and are consistently greater for species inhabiting relatively open or sparsely vegetated habitat. Unlike in marsupials, where some species have much larger body size than rodents, body mass was not an important predictor of decline in rodents. All Australian rodent species are within the prey-size range of cats (throughout the continent and red foxes (in the south. Contrary to the hypothesis that mammal declines are related directly to ecosystem productivity (annual rainfall, our results are consistent with the hypothesis that disturbances such as fire and grazing, which occur in non-rainforest habitats and remove cover used by rodents for shelter, nesting and foraging, increase predation risk. We agree with calls to introduce conservation management that limits the size and intensity of fires, increases fire patchiness and reduces grazing impacts at ecological scales appropriate for rodents. Controlling feral predators, even creating predator-free reserves in relatively sparsely-vegetated habitats, is urgently required to ensure the survival of rodent species, particularly in northern Australia where declines are not yet as severe as those in the south.

    11. Public health implications of changing rodent importation patterns— United States, 1999–2013

      Science.gov (United States)

      Lankau, Emily W.; Sinclair, Julie R.; Schroeder, Betsy A.; Galland, G. Gale; Marano, Nina

      2015-01-01

      Summary The United States imports a large volume of live wild and domestic animal species; these animals pose a demonstrated risk for introduction of zoonotic diseases. Rodents are imported for multiple purposes, including scientific research, zoo exhibits, and the pet trade. Current U.S. public health regulatory restrictions specific to rodent importation pertain only to those of African origin. To understand the impacts of these regulations and the potential public health risks of international rodent trade to the United States, we evaluated live rodent import records during 1999 –2013 by shipment volume and geographic origin, source (e.g., wild -caught versus captive-or commercially bred), intended purpose, and rodent taxonomy. Live rodent imports increased from 2,737 animals during 1999 to 173,761 animals during 2013. Increases in both the number and size of shipments contributed to this trend. The proportion of wild-captured imports declined from 75% during 1999 to guinea pigs, and hamsters arriving from other countries in North America were predominant taxa underlying this trend . After 2003, African-origin imports became sporadic events under the federal permit process. These patterns suggest development of large -scale captive rodent breeding markets abroad for commercial sale in the United States. While the shift from wild-captured imports alleviates many conservation concerns and risks for novel disease emergence, such consolidated sourcing might elevate exposure risks for zoonotic diseases associated with high-density rodent breeding(e.g. , lymphocytic choriomeningitis or salmonellosis). A responsive border health system must periodically re-evaluate importation regulations in conjunction with key stakeholders to ensure a balance between the economic benefits of rodent trade against the potential public health risks. PMID:26245515

    12. Public Health Implications of Changing Rodent Importation Patterns - United States, 1999-2013.

      Science.gov (United States)

      Lankau, E W; Sinclair, J R; Schroeder, B A; Galland, G G; Marano, N

      2017-04-01

      The United States imports a large volume of live wild and domestic animal species; these animals pose a demonstrated risk for introduction of zoonotic diseases. Rodents are imported for multiple purposes, including scientific research, zoo exhibits and the pet trade. Current U.S. public health regulatory restrictions specific to rodent importation pertain only to those of African origin. To understand the impacts of these regulations and the potential public health risks of international rodent trade to the United States, we evaluated live rodent import records during 1999-2013 by shipment volume and geographic origin, source (e.g. wild-caught versus captive- or commercially bred), intended purpose and rodent taxonomy. Live rodent imports increased from 2737 animals during 1999 to 173 761 animals during 2013. Increases in both the number and size of shipments contributed to this trend. The proportion of wild-captured imports declined from 75% during 1999 to guinea pigs and hamsters arriving from other countries in North America were predominant taxa underlying this trend. After 2003, African-origin imports became sporadic events under the federal permit process. These patterns suggest development of large-scale captive rodent breeding markets abroad for commercial sale in the United States. While the shift from wild-captured imports alleviates many conservation concerns and risks for novel disease emergence, such consolidated sourcing might elevate exposure risks for zoonotic diseases associated with high-density rodent breeding (e.g. lymphocytic choriomeningitis or salmonellosis). A responsive border health system must periodically re-evaluate importation regulations in conjunction with key stakeholders to ensure a balance between the economic benefits of rodent trade against the potential public health risks. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

    13. Taxonomical studies of ticks infesting wild rodents from Asir Province in Saudi Arabia.

      Science.gov (United States)

      Al-Mohammed, Hamdan I

      2008-04-01

      Ticks infesting rodents in Asir Province, which is about 3000 meter above sea level, were surveyed in Wadi Dalaghan and Wadi Bin Hachbal. They were examined from September to December 2006, where ten local life baited traps were distributed for 3 days each month. The rodents were Acomys c. dimitatus (20), Meriones rex (19) & one Gerbillus cheesmani. Fifty three nymphs were dropped off from the rodents in the laboratory 3 to 12 days post-trapping. Forty eight nymphs were reared to adults for identification and 5 ones died. The reared ticks were Rhipicephalus turanicus and R. sanguineus. The medical and veterinary importance was discussed.

    14. Segmentation of rodent whole-body dynamic PET images: an unsupervised method based on voxel dynamics

      DEFF Research Database (Denmark)

      Maroy, Renaud; Boisgard, Raphaël; Comtat, Claude

      2008-01-01

      Positron emission tomography (PET) is a useful tool for pharmacokinetics studies in rodents during the preclinical phase of drug and tracer development. However, rodent organs are small as compared to the scanner's intrinsic resolution and are affected by physiological movements. We present a new...... method for the segmentation of rodent whole-body PET images that takes these two difficulties into account by estimating the pharmacokinetics far from organ borders. The segmentation method proved efficient on whole-body numerical rat phantom simulations, including 3-14 organs, together...

    15. Prospective respiratory-gated micro-CT of free breathing rodents

      International Nuclear Information System (INIS)

      Ford, Nancy L.; Nikolov, Hristo N.; Norley, Chris J.D.; Thornton, Michael M.; Foster, Paula J.; Drangova, Maria; Holdsworth, David W.

      2005-01-01

      Microcomputed tomography (Micro-CT) has the potential to noninvasively image the structure of organs in rodent models with high spatial resolution and relatively short image acquisition times. However, motion artifacts associated with the normal respiratory motion of the animal may arise when imaging the abdomen or thorax. To reduce these artifacts and the accompanying loss of spatial resolution, we propose a prospective respiratory gating technique for use with anaesthetized, free-breathing rodents. A custom-made bed with an embedded pressure chamber was connected to a pressure transducer. Anaesthetized animals were placed in the prone position on the bed with their abdomens located over the chamber. During inspiration, the motion of the diaphragm caused an increase in the chamber pressure, which was converted into a voltage signal by the transducer. An output voltage was used to trigger image acquisition at any desired time point in the respiratory cycle. Digital radiographic images were acquired of anaesthetized, free-breathing rats with a digital radiographic system to correlate the respiratory wave form with respiration-induced organ motion. The respiratory wave form was monitored and recorded simultaneously with the x-ray radiation pulses, and an imaging window was defined, beginning at end expiration. Phantom experiments were performed to verify that the respiratory gating apparatus was triggering the micro-CT system. Attached to the distensible phantom were 100 μm diameter copper wires and the measured full width at half maximum was used to assess differences in image quality between respiratory-gated and ungated imaging protocols. This experiment allowed us to quantify the improvement in the spatial resolution, and the reduction of motion artifacts caused by moving structures, in the images resulting from respiratory-gated image acquisitions. The measured wire diameters were 0.135 mm for the stationary phantom image, 0.137 mm for the image gated at end

    16. The role of succulent halophytes in the water balance of salt marsh rodents.

      Science.gov (United States)

      Coulombe, Harry N

      1970-09-01

      The role of succulent halophytes in the water balance and ecology of salt marsh rodents is dependent upon an evaluation of the composition of the available sources and the physiological properties of their potential consumers. Studies of the osmotic properties of succulent halophytes from southern California coastal salt marshes are presented, together with experiments regarding the utilization of Common Pickleweed (Salicornia virginica L.) by indigenous populations of cricetid rodents (harvest mouse Reithrodontomys megalotis limicola Von Bloecker, and meadow-mouse Microtus californicus stephensi Von Bloecker). These data are discussed in relation to other available information concerning the ecology of coastal salt marshes, particularly in western North America.Extruded sap of Common Pickleweed was found to have a mean total osmotic pressure (TOP) of 1,450 mOsm/liter, with an average chloride ion content of 876 mEq/liter (about 70% of the TOP). A related species, Salicornia subterminale, had a slightly lower TOP (1,300 mOsm/liter), of which about 29% was accounted for by chloride ion concentration. Sea Blight (Suaeda fruticosa) was the only species in which the TOP correlated with the distance from the tide level; sap TOP increased away from the lagoon's edge. In both Sea Blight and Common Pickle weed, TOP was not directly related to chloride content, indicating the importance of other osmotically active solutes.Harvest mice were placed on three experimental regimes: 1) millet seeds only, 2) pickleweed only, and 3) pickleweed and millet seed. Meadow mice were tested on the last regime only. Harvest mice survived best on a strict millet seed diet; when Salicornia was consumed to a detectable extent, the mice did not survive. Meadow mice, however, could survive using Salicornia as a dietary source in conjunction with seeds. Kidney electrolyte concentrating abilities indicated that harvest mice should be able to utilize pickleweed; this was not confirmed in my

    17. Identification of collected ectoparasites of rodents in the west of Khuzestan Province (Ahvaz and Hovizeh, southwest of Iran

      Directory of Open Access Journals (Sweden)

      Mahmood Rahdar

      2015-08-01

      Full Text Available Objective: To determine possible parasitic arthropods fauna in certain rodent species in the west of Khuzestan Province including Ahvaz and its suburb and suburb of Hovizeh, southwest of Iran. Methods: In the current study Sherman live traps were used to catch the rodents. The rodents were identified using Iranian keys of rodents. The ectoparasites were picked up in different ways from bodies of the anesthetized rodents and stored in 70% ethanol to preserve and identified using international keys. Results: In the present study 3 species and 4 genera of ectoparasites and 4 species of rodents were identified. Conclusions: It is important to explain that the great ectoparasite biodiversity in the west of Khuzestan, with small sampling of rodents, described a high risk factor to transmit the different infectious diseases among domestic animals and humans.

    18. Effects of parasitism on host reproductive investment in a rodent-flea system: host litter size matters.

      Science.gov (United States)

      Warburton, Elizabeth M; Khokhlova, Irina S; Dlugosz, Elizabeth M; Der Mescht, Luther Van; Krasnov, Boris R

      2017-02-01

      Parents may alter offspring phenotype depending on the type of environment they encounter. Parasitism is a common stressor; therefore, maternal reproductive investment could change in response to parasitic infection. However, few experiments have investigated the relationship between parasitism and maternal investment, whereas earlier field studies provided contradictory evidence. We investigated number, sex ratio, and growth of offspring in two rodent species, solitary altricial Meriones crassus and social precocial Acomys cahirinus, exposed to parasitism by fleas Xenopsylla ramesis and Parapulex chephrenis. No effect of treatment on litter size or sex ratio of a litter was found in either rodent species. Flea parasitism was found to affect pre-weaning body mass gain in M. crassus, but not in A. cahirinus pups. Furthermore, it appeared that female M. crassus invested resources into their offspring differently in dependence of litter size. In small litters (1-3 offspring), pups from infested females gained more body mass before weaning than pups from uninfested mothers. However, this trend was reversed in females with large litters indicating that parasitized females have a finite amount of resources with which to provision their young. Thus, M. crassus mothers parasitized by fleas seemed to receive some sort of external cues (e.g., stress caused by infestation) that prompted them to alter offspring provisioning, depending on species-specific possibilities and constraints. Therefore, parasites could be a mediator of environmentally induced maternal effects and offspring provisioning may have adaptive value against parasitism.

    19. Non-invasive imaging and monitoring of rodent retina using simultaneous dual-band optical coherence tomography

      Science.gov (United States)

      Cimalla, Peter; Burkhardt, Anke; Walther, Julia; Hoefer, Aline; Wittig, Dierk; Funk, Richard; Koch, Edmund

      2011-03-01

      Spectral domain dual-band optical coherence tomography for simultaneous imaging of rodent retina in the 0.8 μm and 1.3 μm wavelength region and non-invasive monitoring of the posterior eye microstructure in the field of retinal degeneration research is demonstrated. The system is illuminated by a supercontinuum laser source and allows three-dimensional imaging with high axial resolution better than 3.8 μm and 5.3 μm in tissue at 800 nm and 1250 nm, respectively, for precise retinal thickness measurements. A fan-shaped scanning pattern with the pivot point close to the eye's pupil and a contact lens are applied to obtain optical access to the eye's fundus. First in vivo experiments in a RCS (royal college of surgeons) rat model with gene-related degeneration of the photoreceptor cells show good visibility of the retinal microstructure with sufficient contrast for thickness measurement of individual retinal layers. An enhanced penetration depth at 1250 nm is clearly identifiable revealing sub-choroidal structures that are not visible at 800 nm. Furthermore, additional simultaneous imaging at 1250 nm improves image quality by frequency compounding speckle noise reduction. These results are encouraging for time course studies of the rodent retina concerning its development related to disease progression and treatment response.

    20. Central administration of the anorexigenic peptide neuromedin U decreases alcohol intake and attenuates alcohol-induced reward in rodents.

      Science.gov (United States)

      Vallöf, Daniel; Ulenius, Lisa; Egecioglu, Emil; Engel, Jörgen A; Jerlhag, Elisabet

      2017-05-01

      By investigating the neurochemical mechanisms through which alcohol activates the brain reward systems, novel treatment strategies for alcohol use disorder (AUD), a chronic relapsing disease, can be developed. In contrast to the common view of the function of gut-brain peptides, such as neuromedin U (NMU), to regulate food intake and appetite, a novel role in reinforcement mediation has been implied. The anorexigenic effects of NMU are mediated via NMU2 receptors, preferably in the arcuate nucleus and paraventricular nucleus. The expression of NMU2 receptors is also expressed in several reward-related areas in the brain, suggesting a role in reward regulation. The present experiments were therefore set up to investigate the effect of intracerebroventricular administration of NMU on alcohol-mediated behaviors in rodents. We found that central administration of NMU attenuated alcohol-induced locomotor stimulation, accumbal dopamine release and the expression of conditioned place preference in mice. In addition, NMU dose dependently decreased alcohol intake in high, but not in low, alcohol-consuming rats. Central NMU administration did not alter the blood alcohol concentrations nor change the corticosterone levels in rodents. Given that AUD is a major health-care challenge causing an enormous cost to society and novel treatment strategies are warranted, our data suggest that NMU analogues deserve to be evaluated as novel treatment of AUD in humans. © 2016 The Authors Addiction Biology published by John Wiley & Sons Ltd.

    1. Self-willed learning: experiments in wild pedagogy

      Science.gov (United States)

      Jickling, Bob

      2015-03-01

      This paper is comprised of written text and photographs of wild experiences that relive a series of ontological experiments. The text represents reflections on these experiences. The photographs, artistic expressions of the same experiences, have been made with a homemade pinhole camera—without a lens and viewfinder—thus demanding special sensual presence during creation. The form of this experimental work is reminiscent of a lyric philosophy that seeks to engage the participant—reader of text and viewer of images—with these experiments. Component pairings are arranged for viewing with text on the left and photographs on the right. Together these parings invite participants to explore patterned resonances in the world. Implicit throughout are considerations of relationships between wildness, wild learning, and a form of wild pedagogy.

    2. Impaired fear extinction in adolescent rodents: Behavioural and neural analyses.

      Science.gov (United States)

      Baker, Kathryn D; Bisby, Madelyne A; Richardson, Rick

      2016-11-01

      Despite adolescence being a developmental window of vulnerability, up until very recently there were surprisingly few studies on fear extinction during this period. Here we summarise the recent work in this area, focusing on the unique behavioural and neural characteristics of fear extinction in adolescent rodents, and humans where relevant. A prominent hypothesis posits that anxiety disorders peak during late childhood/adolescence due to the non-linear maturation of the fear inhibition neural circuitry. We discuss evidence that impaired extinction retention in adolescence is due to subregions of the medial prefrontal cortex and amygdala mediating fear inhibition being underactive while other subregions that mediate fear expression are overactive. We also review work on various interventions and surprising circumstances which enhance fear extinction in adolescence. This latter work revealed that the neural correlates of extinction in adolescence are different to that in younger and older animals even when extinction retention is not impaired. This growing body of work highlights that adolescence is a unique period of development for fear inhibition. Copyright © 2016 Elsevier Ltd. All rights reserved.

    3. Reliable critical sized defect rodent model for cleft palate research.

      Science.gov (United States)

      Mostafa, Nesrine Z; Doschak, Michael R; Major, Paul W; Talwar, Reena

      2014-12-01

      Suitable animal models are necessary to test the efficacy of new bone grafting therapies in cleft palate surgery. Rodent models of cleft palate are available but have limitations. This study compared and modified mid-palate cleft (MPC) and alveolar cleft (AC) models to determine the most reliable and reproducible model for bone grafting studies. Published MPC model (9 × 5 × 3 mm(3)) lacked sufficient information for tested rats. Our initial studies utilizing AC model (7 × 4 × 3 mm(3)) in 8 and 16 weeks old Sprague Dawley (SD) rats revealed injury to adjacent structures. After comparing anteroposterior and transverse maxillary dimensions in 16 weeks old SD and Wistar rats, virtual planning was performed to modify MPC and AC defects dimensions, taking the adjacent structures into consideration. Modified MPC (7 × 2.5 × 1 mm(3)) and AC (5 × 2.5 × 1 mm(3)) defects were employed in 16 weeks old Wistar rats and healing was monitored by micro-computed tomography and histology. Maxillary dimensions in SD and Wistar rats were not significantly different. Preoperative virtual planning enhanced postoperative surgical outcomes. Bone healing occurred at defect margin leaving central bone void confirming the critical size nature of the modified MPC and AC defects. Presented modifications for MPC and AC models created clinically relevant and reproducible defects. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

    4. A novel approach to scavenging anesthetic gases in rodent surgery.

      Science.gov (United States)

      Nesbitt, Jeffrey C; Krageschmidt, Dale A; Blanco, Michael C

      2013-01-01

      Laboratory animal procedures using gas anesthetics may amass elevated waste gas concentrations in operating rooms if controls are not implemented for capturing and removing the vapors. Area sampling using an infrared analyzer indicated isoflurane concentrations likely to exceed occupational exposure guidelines. Our study showed environmental concentrations of oxygen as high as 40% and isoflurane concentrations >100 ppm when no controls or merely passive controls were utilized. These extraneous isoflurane emissions were determined to be originating from the pre-procedural induction process as well as the gas delivery nose cone. A novel waste gas collection cylinder was designed to enclose the gas delivery nose cone and animal head during the administration of anesthetic gases. The vented cylinder utilized a house vacuum to remove the waste anesthetic gases from the surgical field. A commercially available induction chamber designed to be actively and externally exhausted was used to lower concentrations during the induction process. With implementation of local exhaust ventilation controls, waste anesthetic gas concentrations decreased to below recommended occupational exposure levels. In vitro (sham) testing compared favorably to in vivo measurements validating the reduction capability of active ventilation during rodent anesthetic administration. In vivo isoflurane reductions for the induction chamber emissions, the operating room, and the surgeon's breathing zone were 95%, 60%, and 53%, respectively. The same measurements for an in vitro procedure were 98%, 84%, and 87%, respectively.

    5. Rodent Models of Non-classical Progesterone Action Regulating Ovulation

      Directory of Open Access Journals (Sweden)

      Melinda A. Mittelman-Smith

      2017-07-01

      Full Text Available It is becoming clear that steroid hormones act not only by binding to nuclear receptors that associate with specific response elements in the nucleus but also by binding to receptors on the cell membrane. In this newly discovered manner, steroid hormones can initiate intracellular signaling cascades which elicit rapid effects such as release of internal calcium stores and activation of kinases. We have learned much about the translocation and signaling of steroid hormone receptors from investigations into estrogen receptor α, which can be trafficked to, and signal from, the cell membrane. It is now clear that progesterone (P4 can also elicit effects that cannot be exclusively explained by transcriptional changes. Similar to E2 and its receptors, P4 can initiate signaling at the cell membrane, both through progesterone receptor and via a host of newly discovered membrane receptors (e.g., membrane progesterone receptors, progesterone receptor membrane components. This review discusses the parallels between neurotransmitter-like E2 action and the more recently investigated non-classical P4 signaling, in the context of reproductive behaviors in the rodent.

    6. Reproducibility and replicability of rodent phenotyping in preclinical studies.

      Science.gov (United States)

      Kafkafi, Neri; Agassi, Joseph; Chesler, Elissa J; Crabbe, John C; Crusio, Wim E; Eilam, David; Gerlai, Robert; Golani, Ilan; Gomez-Marin, Alex; Heller, Ruth; Iraqi, Fuad; Jaljuli, Iman; Karp, Natasha A; Morgan, Hugh; Nicholson, George; Pfaff, Donald W; Richter, S Helene; Stark, Philip B; Stiedl, Oliver; Stodden, Victoria; Tarantino, Lisa M; Tucci, Valter; Valdar, William; Williams, Robert W; Würbel, Hanno; Benjamini, Yoav

      2018-04-01

      The scientific community is increasingly concerned with the proportion of published "discoveries" that are not replicated in subsequent studies. The field of rodent behavioral phenotyping was one of the first to raise this concern, and to relate it to other methodological issues: the complex interaction between genotype and environment; the definitions of behavioral constructs; and the use of laboratory mice and rats as model species for investigating human health and disease mechanisms. In January 2015, researchers from various disciplines gathered at Tel Aviv University to discuss these issues. The general consensus was that the issue is prevalent and of concern, and should be addressed at the statistical, methodological and policy levels, but is not so severe as to call into question the validity and the usefulness of model organisms as a whole. Well-organized community efforts, coupled with improved data and metadata sharing, have a key role in identifying specific problems and promoting effective solutions. Replicability is closely related to validity, may affect generalizability and translation of findings, and has important ethical implications. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

    7. Use of rodents as models of human diseases

      Directory of Open Access Journals (Sweden)

      Thierry F Vandamme

      2014-01-01

      Full Text Available Advances in molecular biology have significantly increased the understanding of the biology of different diseases. However, these discoveries have not yet been fully translated into improved treatments for patients with diseases such as cancers. One of the factors limiting the translation of knowledge from preclinical studies to the clinic has been the limitations of in vivo diseases models. In this brief review, we will discuss the advantages and disadvantages of rodent models that have been developed to simulate human pathologies, focusing in models that employ xenografts and genetic modification. Within the framework of genetically engineered mouse (GEM models, we will review some of the current genetic strategies for modeling diseases in the mouse and the preclinical studies that have already been undertaken. We will also discuss how recent improvements in imaging technologies may increase the information derived from using these GEMs during early assessments of potential therapeutic pathways. Furthermore, it is interesting to note that one of the values of using a mouse model is the very rapid turnover rate of the animal, going through the process of birth to death in a very short timeframe relative to that of larger mammalian species.

    8. Citral reduces nociceptive and inflammatory response in rodents

      Directory of Open Access Journals (Sweden)

      Lucindo J. Quintans-Júnior

      2011-04-01

      Full Text Available Citral (CIT, which contains the chiral enantiomers, neral (cis and geranial (trans, is the majority monoterpene from Lippia alba and Cymbopogon citratus. The present study aimed to evaluate CIT for antinociceptive and anti-inflammatory activities in rodents. Antinociceptive and anti-inflammatory effects were studied by measuring nociception through acetic acid and formalin tests, while inflammation was verified by inducing peritonitis and paw edema with carrageenan. All tested doses of CIT had significant protection (p<0.001 against acetic acid (0.8% induced nociceptive behavior and the effects were also similar to morphine while formalin induced nociception was significantly protected (p<0.05 only at higher dose (200 mg/kg of CIT in the first phase of the test. CIT significantly reduce (p<0.001 nociceptive behavior emanating from inflammation in second phase at all the doses.The pretreatment with CIT (100 and 200 mg/kg significantly reduced the paw edema induced by carrageenan. Moreover, systemic treatment with CIT (100 and 200 mg/kg significantly reduced (p<0.001 the leukocyte migration in the carrageenan-induced migration to the peritoneal cavity. Our investigation shows that CIT possess significant central and peripheral antinociceptive effects. It was also verified an anti-inflammatory activity. All together these results suggest that CIT might represent important tool for treatment of painful conditions.

    9. Citral reduces nociceptive and inflammatory response in rodents

      Directory of Open Access Journals (Sweden)

      Lucindo J. Quintans-Júnior

      2011-06-01

      Full Text Available Citral (CIT, which contains the chiral enantiomers, neral (cis and geranial (trans, is the majority monoterpene from Lippia alba and Cymbopogon citratus. The present study aimed to evaluate CIT for antinociceptive and anti-inflammatory activities in rodents. Antinociceptive and anti-inflammatory effects were studied by measuring nociception through acetic acid and formalin tests, while inflammation was verified by inducing peritonitis and paw edema with carrageenan. All tested doses of CIT had significant protection (p<0.001 against acetic acid (0.8% induced nociceptive behavior and the effects were also similar to morphine while formalin induced nociception was significantly protected (p<0.05 only at higher dose (200 mg/kg of CIT in the first phase of the test. CIT significantly reduce (p<0.001 nociceptive behavior emanating from inflammation in second phase at all the doses.The pretreatment with CIT (100 and 200 mg/kg significantly reduced the paw edema induced by carrageenan. Moreover, systemic treatment with CIT (100 and 200 mg/kg significantly reduced (p<0.001 the leukocyte migration in the carrageenan-induced migration to the peritoneal cavity. Our investigation shows that CIT possess significant central and peripheral antinociceptive effects. It was also verified an anti-inflammatory activity. All together these results suggest that CIT might represent important tool for treatment of painful conditions.

    10. Uso tradicional de plantas medicinales en la vereda San Isidro, municipio de San José de Pare-Boyacá: un estudio preliminar usando técnicas cuantitativas

      Directory of Open Access Journals (Sweden)

      Jarvis Yamith Toscano González

      2006-07-01

      Full Text Available Se evaluó cuantitativamente el uso de plantas medicinales con el propósito de documentar la importancia relativa de dichas especies y estimar el estado actual del conocimiento tradicional de las comunidades campesinas de la vereda San Isidro, municipio de San José de Pare, Boyacá. Esta zona en particular, se considera un sector agrícola de alta confluencia y denota una apropiación del conocimiento de sus pobladores en el uso y manejo de las especies vegetales de la región. Se aplicaron aleatoriamente 180 encuestas a personas entre los 20 y 80 años, en donde se investigó respecto al uso y manejo de las plantas. Se aplicaron entrevistas programadas a aquellas personas que manejan en gran parte la demanda de plantas medicinales en la región. Los datos obtenidos a partir del consenso de informantes, fueron analizados mediante el índice de valor de uso (IVU y el nivel de uso significativo de TRAMIL. Se registraron 84 especies con 78 géneros, agrupadas en 42 familias botánicas entre medicinales, aromáticas y mágico-religiosas; las familias mejor representadas fueron Lamiaceae, Asteraceae, Apiaceae, Solanaceae y Rutaceae. Se reportaron 10 especies con un mayor nivel de uso significativo y 25 especies con un mayor IVU. La documentación de los usos de las plantas medicinales en el área de influencia, revela que el conocimiento tradicional continúa profundamente arraigado entre la comunidad y se mantiene el saber popular a manos de curanderos y madres cabeza de familia.

    11. Rodent Research-1 (RR1) NASA Validation Flight: Mouse liver transcriptomic proteomic and epigenomic data

      Data.gov (United States)

      National Aeronautics and Space Administration — RR-1 is a validation flight to evaluate the hardware operational and science capabilities of the Rodent Research Project on the ISS. RNA DNA and protein were...

    12. Accelerated cognitive decline in a rodent model for temporal lobe epilepsy

      NARCIS (Netherlands)

      Schipper, Sandra; Aalbers, Marlien W.; Rijkers, Kim; Lagiere, Melanie; Bogaarts, Jan G.; Blokland, Arjan; Klinkenberg, Sylvia; Hoogland, Govert; Vles, Johan S. H.

      2016-01-01

      Objective: Cognitive impairment is frequently observed in patients with temporal lobe epilepsy. It is hypothesized that cumulative seizure exposure causes accelerated cognitive decline in patients with epilepsy. We investigated the influence of seizure frequency on cognitive decline in a rodent

    13. Studies into abnormal aggression in humans and rodents: Methodological and translational aspects.

      Science.gov (United States)

      Haller, Jozsef

      2017-05-01

      Here we review the principles based on which aggression is rendered abnormal in humans and laboratory rodents, and comparatively overview the main methodological approaches based on which this behavior is studied in the two categories of subjects. It appears that the discriminating property of abnormal aggression is rule breaking, which renders aggression dysfunctional from the point of view of the perpetrator. We show that rodent models of abnormal aggression were created by the translation of human conditions into rodent equivalents, and discuss how findings obtained with such models may be "translated back" to human conditions when the mechanisms underlying aggression and its possibilities of treatment are investigated. We suggest that the complementary nature of human and rodent research approaches invite a more intense cross-talk between the two sides of aggression research than the one presently observed. Copyright © 2017 Elsevier Ltd. All rights reserved.

    14. Vagus nerve stimulation inhibits trigeminal nociception in a rodent model of episodic migraine

      Directory of Open Access Journals (Sweden)

      Jordan L. Hawkins

      2017-12-01

      Conclusion:. Our findings demonstrate that nVNS inhibits mechanical nociception and represses expression of proteins associated with peripheral and central sensitization of trigeminal neurons in a novel rodent model of episodic migraine.

    15. Rodent Research-1 (RR1) NASA Validation Flight: Mouse soleus muscle transcriptomic and epigenomic data

      Data.gov (United States)

      National Aeronautics and Space Administration — NASA s Rodent Research (RR) project is playing a critical role in advancing biomedical research on the physiological effects of space environments. Due to the...

    16. Rodent Research-1 (RR1) NASA Validation Flight: Mouse kidney transcriptomic proteomic and epigenomic data

      Data.gov (United States)

      National Aeronautics and Space Administration — NASA s Rodent Research (RR) project is playing a critical role in advancing biomedical research on the physiological effects of space environments. Due to the...

    17. Rodent Research-1 (RR1) NASA Validation Flight: Mouse quadriceps muscle transcriptomic proteomic and epigenomic data

      Data.gov (United States)

      National Aeronautics and Space Administration — NASA s Rodent Research (RR) project is playing a critical role in advancing biomedical research on the physiological effects of space environments. Due to the...

    18. Rodent Research-1 (RR1) NASA Validation Flight: Mouse gastrocnemius muscle transcriptomic proteomic and epigenomic data

      Data.gov (United States)

      National Aeronautics and Space Administration — NASA s Rodent Research (RR) project is playing a critical role in advancing biomedical research on the physiological effects of space environments. Due to the...

    19. Rodent Research-1 (RR1) NASA Validation Flight: Mouse eye transcriptomic and epigenomic data

      Data.gov (United States)

      National Aeronautics and Space Administration — NASA s Rodent Research (RR) project is playing a critical role in advancing biomedical research on the physiological effects of space environments. Due to the...

    20. Rodent Research-1 (RR1) NASA Validation Flight: Mouse adrenal gland transcriptomic proteomic and epigenomic data

      Data.gov (United States)

      National Aeronautics and Space Administration — NASA s Rodent Research (RR) project is playing a critical role in advancing biomedical research on the physiological effects of space environments. Due to the...

    1. Neurobiological basis of chemotherapy-induced cognitive impairment : A review of rodent research

      NARCIS (Netherlands)

      Seigers, Riejanne; Fardell, Joanna E.

      For some cancer survivors chemotherapy treatment is associated with lasting cognitive impairment, long after treatment cessation. Several candidate mechanisms have been suggested, yet clinical research has been unable to clearly tease apart these hypotheses. Rodent research has allowed a systematic

    2. Gut morpbology of tbe Otomyine rodents: an arid-mesic comparison

      African Journals Online (AJOL)

      1998-06-15

      Jun 15, 1998 ... Despite the broad similarity in the gross gastro-intestinal anatomy between the speCies ... Present address: Department of Physiology, University of the Western ..... on growth and renal performance of juvenile Namib rodents.

    3. Establishment of a general NAFLD scoring system for rodent models and comparison to human liver pathology

      NARCIS (Netherlands)

      Liang, W.; Menke, A.L.; Driessen, A.; Koek, G.H.; Lindeman, J.H.; Stoop, R.; Havekes, L.M.; Kleemann., R.; Hoek, A.M. van den

      2014-01-01

      Results: The criteria macrovesicular steatosis, microvesicular steatosis, hepatocellular hypertrophy, inflammation and fibrosis were generally applicable to rodent NAFLD. The inter-observer reproducibility (evaluated using the Intraclass Correlation Coefficient) between the ten observers was high

    4. Verification of natural infection of peridomestic rodents by PCV2 on commercial swine farms.

      Science.gov (United States)

      Pinheiro, Albanno Leonard Braz Campos; Bulos, Luiz Henrique Silva; Onofre, Thiago Souza; de Paula Gabardo, Michelle; de Carvalho, Otávio Valério; Fausto, Mariana Costa; Guedes, Roberto Maurício Carvalho; de Almeida, Márcia Rogéria; Silva Júnior, Abelardo

      2013-06-01

      The porcine circovirus-2 (PCV2) is the main agent responsible for porcine circovirus associated diseases (PCVAD). Few studies have been done regarding PCV2 infection in other species. The purpose of this study was to investigate the occurrence of PCV2 infection in the peridomestic rodent species Mus musculus and Rattus rattus on commercial pig farms in Brazil. Immunohistochemistry assay demonstrated PCV2 in the spleen, lung and kidney. Viral DNA was detected in tissues by nested PCR assay. Partial sequences of PCV2 genomes detected in the rodents had strong identity with gene sequences of PCV2 isolates from pigs. These results show that the studied peridomestic rodent species can be naturally infected by PCV2. However, further studies are needed to confirm PCV2 transmission from rodents to pigs. Copyright © 2012 Elsevier Ltd. All rights reserved.

    5. Opportunities for improving animal welfare in rodent models of epilepsy and seizures.

      Science.gov (United States)

      Lidster, Katie; Jefferys, John G; Blümcke, Ingmar; Crunelli, Vincenzo; Flecknell, Paul; Frenguelli, Bruno G; Gray, William P; Kaminski, Rafal; Pitkänen, Asla; Ragan, Ian; Shah, Mala; Simonato, Michele; Trevelyan, Andrew; Volk, Holger; Walker, Matthew; Yates, Neil; Prescott, Mark J

      2016-02-15

      Animal models of epilepsy and seizures, mostly involving mice and rats, are used to understand the pathophysiology of the different forms of epilepsy and their comorbidities, to identify biomarkers, and to discover new antiepileptic drugs and treatments for comorbidities. Such models represent an important area for application of the 3Rs (replacement, reduction and refinement of animal use). This report provides background information and recommendations aimed at minimising pain, suffering and distress in rodent models of epilepsy and seizures in order to improve animal welfare and optimise the quality of studies in this area. The report includes practical guidance on principles of choosing a model, induction procedures, in vivo recordings, perioperative care, welfare assessment, humane endpoints, social housing, environmental enrichment, reporting of studies and data sharing. In addition, some model-specific welfare considerations are discussed, and data gaps and areas for further research are identified. The guidance is based upon a systematic review of the scientific literature, survey of the international epilepsy research community, consultation with veterinarians and animal care and welfare officers, and the expert opinion and practical experience of the members of a Working Group convened by the United Kingdom's National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs). Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

    6. Effects of acupuncture and electroacupuncture on estradiol-induced inflammation and oxidative stress in health rodents.

      Science.gov (United States)

      Santos, Elba Lucia Wanderley; Dias, Bruno Hállan Meneses; Andrade, Ana Carolina Rodrigues de; Pascoal, Angélica Maria Holanda; Vasconcelos Filho, Francisco Eugênio de; Medeiros, Francisco das Chagas; Guimarães, Sergio Botelho

      2013-08-01

      To investigate the effects of classical acupuncture (Ac) and electroacupuncture (EAc) on estradiol-induced inflammation and oxidative stress in health rodents. Twenty-four eight-week old female rats were treated with estradiol valerate (EV) 4.0 mg i.m. single dose and randomly assigned to four groups (n=6): G1(control), G2 (Ac), G3 (EAc 2 Hz) and G4 (EAc 100 Hz). After 60 days all rats were anesthetized with chloral hydrate 10% (0.1 ml/30 g weight of the animal) and submitted to Ac/EAc for twenty minutes. The procedures were repeated on days three, five, seven and nine of the study. The equivalent of the human right ST-36 (Zusanli) and SP-6 (Sanyinjiao) acupoints were chosen for needling and electrical stimulation. On the 10th day of the experiment, all rats were anesthetized for collection of blood and tissues (ovaries) samples for biochemical analysis and histological examination. Glutathione (GSH) and malonaldehyde (MDA) concentrations increased significantly in all groups (plasma and ovary) while myeloperoxidase (MPO) activity decreased significantly in all groups compared with control group (G1). Both classical acupuncture and electroacupuncture decrease systemic and local oxidative stress and ovary inflammation in healthy rats exposed to estrogenic stimulation. EAc enhances lipid peroxidation at systemic and local levels in female rats exposed to estrogenic stimulation.

    7. ProTox: a web server for the in silico prediction of rodent oral toxicity.

      Science.gov (United States)

      Drwal, Malgorzata N; Banerjee, Priyanka; Dunkel, Mathias; Wettig, Martin R; Preissner, Robert

      2014-07-01

      Animal trials are currently the major method for determining the possible toxic effects of drug candidates and cosmetics. In silico prediction methods represent an alternative approach and aim to rationalize the preclinical drug development, thus enabling the reduction of the associated time, costs and animal experiments. Here, we present ProTox, a web server for the prediction of rodent oral toxicity. The prediction method is based on the analysis of the similarity of compounds with known median lethal doses (LD50) and incorporates the identification of toxic fragments, therefore representing a novel approach in toxicity prediction. In addition, the web server includes an indication of possible toxicity targets which is based on an in-house collection of protein-ligand-based pharmacophore models ('toxicophores') for targets associated with adverse drug reactions. The ProTox web server is open to all users and can be accessed without registration at: http://tox.charite.de/tox. The only requirement for the prediction is the two-dimensional structure of the input compounds. All ProTox methods have been evaluated based on a diverse external validation set and displayed strong performance (sensitivity, specificity and precision of 76, 95 and 75%, respectively) and superiority over other toxicity prediction tools, indicating their possible applicability for other compound classes. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

    8. Open Source Tools for Temporally Controlled Rodent Behavior Suitable for Electrophysiology and Optogenetic Manipulations

      Directory of Open Access Journals (Sweden)

      Nicola Solari

      2018-05-01

      Full Text Available Understanding how the brain controls behavior requires observing and manipulating neural activity in awake behaving animals. Neuronal firing is timed at millisecond precision. Therefore, to decipher temporal coding, it is necessary to monitor and control animal behavior at the same level of temporal accuracy. However, it is technically challenging to deliver sensory stimuli and reinforcers as well as to read the behavioral responses they elicit with millisecond precision. Presently available commercial systems often excel in specific aspects of behavior control, but they do not provide a customizable environment allowing flexible experimental design while maintaining high standards for temporal control necessary for interpreting neuronal activity. Moreover, delay measurements of stimulus and reinforcement delivery are largely unavailable. We combined microcontroller-based behavior control with a sound delivery system for playing complex acoustic stimuli, fast solenoid valves for precisely timed reinforcement delivery and a custom-built sound attenuated chamber using high-end industrial insulation materials. Together this setup provides a physical environment to train head-fixed animals, enables calibrated sound stimuli and precisely timed fluid and air puff presentation as reinforcers. We provide latency measurements for stimulus and reinforcement delivery and an algorithm to perform such measurements on other behavior control systems. Combined with electrophysiology and optogenetic manipulations, the millisecond timing accuracy will help interpret temporally precise neural signals and behavioral changes. Additionally, since software and hardware provided here can be readily customized to achieve a large variety of paradigms, these solutions enable an unusually flexible design of rodent behavioral experiments.

    9. Open Source Tools for Temporally Controlled Rodent Behavior Suitable for Electrophysiology and Optogenetic Manipulations.

      Science.gov (United States)

      Solari, Nicola; Sviatkó, Katalin; Laszlovszky, Tamás; Hegedüs, Panna; Hangya, Balázs

      2018-01-01

      Understanding how the brain controls behavior requires observing and manipulating neural activity in awake behaving animals. Neuronal firing is timed at millisecond precision. Therefore, to decipher temporal coding, it is necessary to monitor and control animal behavior at the same level of temporal accuracy. However, it is technically challenging to deliver sensory stimuli and reinforcers as well as to read the behavioral responses they elicit with millisecond precision. Presently available commercial systems often excel in specific aspects of behavior control, but they do not provide a customizable environment allowing flexible experimental design while maintaining high standards for temporal control necessary for interpreting neuronal activity. Moreover, delay measurements of stimulus and reinforcement delivery are largely unavailable. We combined microcontroller-based behavior control with a sound delivery system for playing complex acoustic stimuli, fast solenoid valves for precisely timed reinforcement delivery and a custom-built sound attenuated chamber using high-end industrial insulation materials. Together this setup provides a physical environment to train head-fixed animals, enables calibrated sound stimuli and precisely timed fluid and air puff presentation as reinforcers. We provide latency measurements for stimulus and reinforcement delivery and an algorithm to perform such measurements on other behavior control systems. Combined with electrophysiology and optogenetic manipulations, the millisecond timing accuracy will help interpret temporally precise neural signals and behavioral changes. Additionally, since software and hardware provided here can be readily customized to achieve a large variety of paradigms, these solutions enable an unusually flexible design of rodent behavioral experiments.

    10. Hippocampome.org: a knowledge base of neuron types in the rodent hippocampus.

      Science.gov (United States)

      Wheeler, Diek W; White, Charise M; Rees, Christopher L; Komendantov, Alexander O; Hamilton, David J; Ascoli, Giorgio A

      2015-09-24

      Hippocampome.org is a comprehensive knowledge base of neuron types in the rodent hippocampal formation (dentate gyrus, CA3, CA2, CA1, subiculum, and entorhinal cortex). Although the hippocampal literature is remarkably information-rich, neuron properties are often reported with incompletely defined and notoriously inconsistent terminology, creating a formidable challenge for data integration. Our extensive literature mining and data reconciliation identified 122 neuron types based on neurotransmitter, axonal and dendritic patterns, synaptic specificity, electrophysiology, and molecular biomarkers. All ∼3700 annotated properties are individually supported by specific evidence (∼14,000 pieces) in peer-reviewed publications. Systematic analysis of this unprecedented amount of machine-readable information reveals novel correlations among neuron types and properties, the potential connectivity of the full hippocampal circuitry, and outstanding knowledge gaps. User-friendly browsing and online querying of Hippocampome.org may aid design and interpretation of both experiments and simulations. This powerful, simple, and extensible neuron classification endeavor is unique in its detail, utility, and completeness.

    11. Early life stress paradigms in rodents: potential animal models of depression?

      Science.gov (United States)

      Schmidt, Mathias V; Wang, Xiao-Dong; Meijer, Onno C

      2011-03-01

      While human depressive illness is indeed uniquely human, many of its symptoms may be modeled in rodents. Based on human etiology, the assumption has been made that depression-like behavior in rats and mice can be modulated by some of the powerful early life programming effects that are known to occur after manipulations in the first weeks of life. Here we review the evidence that is available in literature for early life manipulation as risk factors for the development of depression-like symptoms such as anhedonia, passive coping strategies, and neuroendocrine changes. Early life paradigms that were evaluated include early handling, separation, and deprivation protocols, as well as enriched and impoverished environments. We have also included a small number of stress-related pharmacological models. We find that for most early life paradigms per se, the actual validity for depression is limited. A number of models have not been tested with respect to classical depression-like behaviors, while in many cases, the outcome of such experiments is variable and depends on strain and additional factors. Because programming effects confer vulnerability rather than disease, a number of paradigms hold promise for usefulness in depression research, in combination with the proper genetic background and adult life challenges.

    12. Bipolar electrocautery: A rodent model of Sunderland third-degree nerve injury.

      Science.gov (United States)

      Moradzadeh, Arash; Brenner, Michael J; Whitlock, Elizabeth L; Tong, Alice Y; Luciano, Janina P; Hunter, Daniel A; Myckatyn, Terence M; Mackinnon, Susan E

      2010-01-01

      To determine the Sunderland classification of a bipolar electrocautery injury. Twenty-two rats received crush (a reproducible Sunderland second-degree injury) or bipolar electrocautery injury and were evaluated for functional, histomorphometric, and immunohistochemical recovery at 21 or 42 days. Animal experiments were performed between July 3 and December 12, 2007. Axonal regeneration and end plate reinnervation were evaluated in double transgenic cyan fluorescent protein-conjugated Thy1 and green fluorescent protein-conjugated S100 mice. Compared with crush injury, bipolar electrocautery injury caused greater disruption of myelin and neurofilament architecture at the injury site and decreased nerve fiber counts and percentage of neural tissue distal to the injury (P =.007). Complete functional recovery was seen after crush but not bipolar electrocautery injury. Serial live imaging demonstrated axonal regeneration at week 1 after crush and at week 3 after bipolar electrocautery injury. Qualitative assessment of motor end plate reinnervation at 42 days demonstrated complete neuromuscular end plate reinnervation in the crush group and only limited reinnervation in the bipolar electrocautery group. Bipolar electrocautery injury in a rodent model resulted in a Sunderland third-degree injury, characterized by gradual, incomplete recovery without intervention.

    13. Assessment of variability in cerebral vasculature for neuro-anatomical surgery planning in rodent brain

      Science.gov (United States)

      Rangarajan, J. R.; Van Kuyck, K.; Himmelreich, U.; Nuttin, B.; Maes, F.; Suetens, P.

      2011-03-01

      Clinical and pre-clinical studies show that deep brain stimulation (DBS) of targeted brain regions by neurosurgical techniques ameliorate psychiatric disorder such as anorexia nervosa. Neurosurgical interventions in preclinical rodent brain are mostly accomplished manually with a 2D atlas. Considering both the large number of animals subjected to stereotactic surgical experiments and the associated imaging cost, feasibility of sophisticated pre-operative imaging based surgical path planning and/or robotic guidance is limited. Here, we spatially normalize vasculature information and assess the intra-strain variability in cerebral vasculature for a neurosurgery planning. By co-registering and subsequently building a probabilistic vasculature template in a standard space, we evaluate the risk of a user defined electrode trajectory damaging a blood vessel on its path. The use of such a method may not only be confined to DBS therapy in small animals, but also could be readily applicable to a wide range of stereotactic small animal surgeries like targeted injection of contrast agents and cell labeling applications.

    14. Periodontal diseases and caries experience of diabetic patients in an Arabian community

      International Nuclear Information System (INIS)

      AlKhateeb, T. L; AlAmoudi, N. H; Fatani, H. H; Mira, S. A; Ardawi, M. S

      1991-01-01

      A group of diabetic patients living in an Arabian community were matched by sex and age with a non-diabetic control group. Examination for periodontal status and dental caries was carried out on the matched pairs. Diabetics exhibited more gingival inflammation and increased probing depths when com pared with age-/sex-matched controls. The caries experience of diabetic patients was higher than that of normal groups. The findings of this study highlight the urgent need to develop a preventive dental program for diabetic patients so as to minimize their experience of dental disease. (author)

    15. The need to implement the landscape of fear within rodent pest management strategies.

      Science.gov (United States)

      Krijger, Inge M; Belmain, Steven R; Singleton, Grant R; Groot Koerkamp, Peter Wg; Meerburg, Bastiaan G

      2017-12-01

      Current reactive pest management methods have serious drawbacks such as the heavy reliance on chemicals, emerging genetic rodenticide resistance and high secondary exposure risks. Rodent control needs to be based on pest species ecology and ethology to facilitate the development of ecologically based rodent management (EBRM). An important aspect of EBRM is a strong understanding of rodent pest species ecology, behaviour and spatiotemporal factors. Gaining insight into the behaviour of pest species is a key aspect of EBRM. The landscape of fear (LOF) is a mapping of the spatial variation in the foraging cost arising from the risk of predation, and reflects the levels of fear a prey species perceives at different locations within its home range. In practice, the LOF maps habitat use as a result of perceived fear, which shows where bait or traps are most likely to be encountered and used by rodents. Several studies have linked perceived predation risk of foraging animals with quitting-harvest rates or giving-up densities (GUDs). GUDs have been used to reflect foraging behaviour strategies of predator avoidance, but to our knowledge very few papers have directly used GUDs in relation to pest management strategies. An opportunity for rodent control strategies lies in the integration of the LOF of rodents in EBRM methodologies. Rodent management could be more efficient and effective by concentrating on those areas where rodents perceive the least levels of predation risk. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

    16. Indirect effects of rodents on arthropods in a Scandinavian boreal forest

      OpenAIRE

      Malá, Barbora

      2016-01-01

      Rodents in boreal forest are an important component of food webs. Their role as drivers of the boreal forest ecosystem is debated. As herbivores they affect plant communities and alter qualities of plants. Consequently availability of food resources for other herbivorous species is altered. In my thesis I studied whether rodents indirectly influence communities of arthropods via plant resources. It is assumed that phytophagous arthropods respond to changes in plant resources by different feed...

    17. Small rodents as paratenic or intermediate hosts of carnivore parasites in Berlin, Germany.

      Directory of Open Access Journals (Sweden)

      Jürgen Krücken

      Full Text Available Rodents are important intermediate and paratenic hosts for carnivore parasites, including the important zoonotic agents Toxoplasma, Echinococcus and Toxocara. Monitoring of such parasites in rodents can be used to detect increasing risks for human and veterinary public health. Rodents were trapped at four sites in Berlin, two near the city center, two at the periphery. PCRs were conducted to detect Coccidia (target ITS-1 and specifically Toxoplasma gondii (repetitive element in brain and ascarids (ITS-2 in muscle or brain tissue. During necropsies, metacestodes were collected and identified using ITS-2 and 12S rRNA PCRs. An ELISA to detect antibodies against Toxocara canis ES antigens was performed. Within the 257 examined rodents, the most frequently observed parasite was Frenkelia glareoli predominantly found in Myodes glareolus. T. gondii was only detected in 12 rodents and Microtus spp. (although strongly underrepresented had a significantly increased chance of being positive. Neither Echinococcus nor typical Taenia parasites of dogs and cats were found but Mesocestoides litteratus and Taenia martis metacestodes were identified which can cause severe peritoneal or ocular cysticercosis in dogs, primates and humans. Using PCR, the ascarids T. canis (n = 8, Toxocara cati (4 and Parascaris sp. (1 were detected predominantly in muscles. Seroprevalence of T. canis was 14.2% and ELISA was thus more sensitive than PCR to detect infection with this parasite. Non-parametric multidimensional scaling and cluster analysis revealed that parasite communities could be grouped into an urban and a peri-urban cluster with high frequency of ascarid-positive rodents in urban and high frequency of F. glareoli in peri-urban sites. Prevalence rates of parasites in rodents with potential impact for human or veterinary public health are considerable and the monitoring of transmission cycles of carnivore parasites in intermediate rodent hosts is recommended to

    18. Small rodents as paratenic or intermediate hosts of carnivore parasites in Berlin, Germany.

      Science.gov (United States)

      Krücken, Jürgen; Blümke, Julia; Maaz, Denny; Demeler, Janina; Ramünke, Sabrina; Antolová, Daniela; Schaper, Roland; von Samson-Himmelstjerna, Georg

      2017-01-01

      Rodents are important intermediate and paratenic hosts for carnivore parasites, including the important zoonotic agents Toxoplasma, Echinococcus and Toxocara. Monitoring of such parasites in rodents can be used to detect increasing risks for human and veterinary public health. Rodents were trapped at four sites in Berlin, two near the city center, two at the periphery. PCRs were conducted to detect Coccidia (target ITS-1) and specifically Toxoplasma gondii (repetitive element) in brain and ascarids (ITS-2) in muscle or brain tissue. During necropsies, metacestodes were collected and identified using ITS-2 and 12S rRNA PCRs. An ELISA to detect antibodies against Toxocara canis ES antigens was performed. Within the 257 examined rodents, the most frequently observed parasite was Frenkelia glareoli predominantly found in Myodes glareolus. T. gondii was only detected in 12 rodents and Microtus spp. (although strongly underrepresented) had a significantly increased chance of being positive. Neither Echinococcus nor typical Taenia parasites of dogs and cats were found but Mesocestoides litteratus and Taenia martis metacestodes were identified which can cause severe peritoneal or ocular cysticercosis in dogs, primates and humans. Using PCR, the ascarids T. canis (n = 8), Toxocara cati (4) and Parascaris sp. (1) were detected predominantly in muscles. Seroprevalence of T. canis was 14.2% and ELISA was thus more sensitive than PCR to detect infection with this parasite. Non-parametric multidimensional scaling and cluster analysis revealed that parasite communities could be grouped into an urban and a peri-urban cluster with high frequency of ascarid-positive rodents in urban and high frequency of F. glareoli in peri-urban sites. Prevalence rates of parasites in rodents with potential impact for human or veterinary public health are considerable and the monitoring of transmission cycles of carnivore parasites in intermediate rodent hosts is recommended to estimate the health

    19. The Upper Miocene rodents from the Pezinok in the Danube Basin, Slovakia

      OpenAIRE

      Peter Joniak

      2016-01-01

      Rodent assemblages are described from two sampled sites at the Pezinok clay pit in the Danube Basin. Although these assemblages contain material poor in specimens, the following eleven rodent taxa are distinguished and described: Progonomys hispanicus, Kowalskia sp., Microtocricetus molassicus, Anomalomys gaillardi, Graphiurops austriacus, Paraglirulus sp., Eomyops catalaunicus, Keramidomys sp., Spermophilinus sp., Albanensia sp. and Euroxenomys minutum. The co-occurrence of very primitive Pr...

    20. Endotoxin, Coliform, and Dust Levels in Various Types of Rodent Bedding

      OpenAIRE

      Whiteside, Tanya E; Thigpen, Julius E; Kissling, Grace E; Grant, Mary G; Forsythe, Diane B

      2010-01-01

      Endotoxins in grain dust, household dust, and animal bedding may induce respiratory symptoms in rodents and humans. We assayed the endotoxin, coliform, and dust levels in 20 types of rodent bedding. Endotoxin concentrations were measured by using a commercial test kit, coliform counts were determined by using conventional microbiologic procedures, and dust content was evaluated by using a rotating–tapping shaker. Paper bedding types contained significantly less endotoxin than did other beddin...

    1. Frutalin reduces acute and neuropathic nociceptive behaviours in rodent models of orofacial pain.

      Science.gov (United States)

      Damasceno, Marina B M V; de Melo Júnior, José de Maria A; Santos, Sacha Aubrey A R; Melo, Luana T M; Leite, Laura Hévila I; Vieira-Neto, Antonio E; Moreira, Renato de A; Monteiro-Moreira, Ana Cristina de O; Campos, Adriana R

      2016-08-25

      Orofacial pain is a highly prevalent clinical condition, yet difficult to control effectively with available drugs. Much attention is currently focused on the anti-inflammatory and antinociceptive properties of lectins. The purpose of this study was to evaluate the antinociceptive effect of frutalin (FTL) using rodent models of inflammatory and neuropathic orofacial pain. Acute pain was induced by formalin, glutamate or capsaicin (orofacial model) and hypertonic saline (corneal model). In one experiment, animals were pretreated with l-NAME and naloxone to investigate the mechanism of antinociception. The involvement of the lectin domain in the antinociceptive effect of FTL was verified by allowing the lectin to bind to its specific ligand. In another experiment, animals pretreated with FTL or saline were submitted to the temporomandibular joint formalin test. In yet another, animals were submitted to infraorbital nerve transection to induce chronic pain, followed by induction of thermal hypersensitivity using acetone. Motor activity was evaluated with the rotarod test. A molecular docking was performed using the TRPV1 channel. Pretreatment with FTL significantly reduced nociceptive behaviour associated with acute and neuropathic pain, especially at 0.5 mg/kg. Antinociception was effectively inhibited by l-NAME and d-galactose. In line with in vivo experiments, docking studies indicated that FTL may interact with TRPV1. Our results confirm the potential pharmacological relevance of FTL as an inhibitor of orofacial nociception in acute and chronic pain mediated by TRPA1, TRPV1 and TRPM8 receptor. Copyright © 2016. Published by Elsevier Ireland Ltd.

    2. Hantavirus pulmonary syndrome and rodent reservoirs in the savanna-like biome of Brazil's southeastern region.

      Science.gov (United States)

      Limongi, J E; Oliveira, R C; Guterres, A; Costa Neto, S F; Fernandes, J; Vicente, L H B; Coelho, M G; Ramos, V N; Ferreira, M S; Bonvicino, C R; D'Andrea, P S; Lemos, E R S

      2016-04-01

      This paper describes the diversity of rodent fauna in an area endemic for hantavirus cardiopulmonary syndrome (HCPS) in Brazil, the population dynamics and the relationship of rodents with hantavirus in the Cerrado (savanna-like) biome. Additionally, an analysis is made of the partial S segment sequences of the hantaviruses obtained from serologically confirmed human HCPS cases and from rodent specimens. Rodents were collected during four campaigns. Human serum samples were collected from suspected cases of HCPS at hospitals in the state of Minas Gerais. The samples antibody-reactive by ELISA were processed by RT-PCR. The PCR product was amplified and sequenced. Hantavirus was detected only in Necromys lasiurus, the wild rodent species most prevalent in the Cerrado biome (min-max: 50-83·7%). All the six human serum samples were hantavirus seropositive and five showed amplified PCR products. The analysis of the nucleotide sequences showed the circulation of a single genotype, the Araraquara hantavirus. The environmental changes that have occurred in the Cerrado biome in recent decades have favoured N. lasiurus in interspecific competition of habitats, thus increasing the risk of contact between humans and rodent species infected with hantavirus. Our data corroborate the definition of N. lasiurus as the main hantavirus reservoir in the Cerrado biome.

    3. A comparison of bats and rodents as reservoirs of zoonotic viruses: are bats special?

      Science.gov (United States)

      Luis, Angela D.; Hayman, David T.S.; O'Shea, Thomas J.; Cryan, Paul M.; Gilbert, Amy T.; Pulliam, Juliet R.C.; Mills, James N.; Timonin, Mary E.; Willis, Craig K.R.; Cunningham, Andrew A.; Fooks, Anthony R.; Rupprecht, Charles E.; Wood, James L.N.; Webb, Colleen T.

      2013-01-01

      Bats are the natural reservoirs of a number of high-impact viral zoonoses. We present a quantitative analysis to address the hypothesis that bats are unique in their propensity to host zoonotic viruses based on a comparison with rodents, another important host order. We found that bats indeed host more zoonotic viruses per species than rodents, and we identified life-history and ecological factors that promote zoonotic viral richness. More zoonotic viruses are hosted by species whose distributions overlap with a greater number of other species in the same taxonomic order (sympatry). Specifically in bats, there was evidence for increased zoonotic viral richness in species with smaller litters (one young), greater longevity and more litters per year. Furthermore, our results point to a new hypothesis to explain in part why bats host more zoonotic viruses per species: the stronger effect of sympatry in bats and more viruses shared between bat species suggests that interspecific transmission is more prevalent among bats than among rodents. Although bats host more zoonotic viruses per species, the total number of zoonotic viruses identified in bats (61) was lower than in rodents (68), a result of there being approximately twice the number of rodent species as bat species. Therefore, rodents should still be a serious concern as reservoirs of emerging viruses. These findings shed light on disease emergence and perpetuation mechanisms and may help lead to a predictive framework for identifying future emerging infectious virus reservoirs.

    4. Intestinal Helminths in Different Species of Rodents in North Khorasan Province, Northeast of Iran

      Directory of Open Access Journals (Sweden)

      Kourosh ARZAMANI

      2017-06-01

      Full Text Available Background: Rodents are an important source of zoonotic diseases for human. The aim of this study was to determine the infectivity of rodents with intestinal helminths in North Khorasan Province, Iran.Methods: One hundred and thirteen rodents were collected using different collection methods such as kill and live traps, digging of their burrow, filling of their hiding places with water and hand net during 2011-2013. Their alimentary canals were removed in the laboratory and helminths were determined in the department of parasitology, Tehran University of Medical Sciences.Results: Thirteen species of helminths parasites were found in 13 species of rodents, including Aspiculuris tetraptera, Hymenolepis diminuta, Nippostrongylus brasiliensis, Protospirura Seurat, Rictolaria ratti, Skrjabinitaenia lobata, Streptopharagus kuntzi, Syphacia obvelata, Taenia taeniaeformis, Trichuris muris, Cysticercus fasciolaris, Acanthocephal. spp and Trichuris spp. Some of them were reported for the first time in new host in Iran. S. obvelata and A. tetraptera were the most frequent parasites and P. Seurat, R. ratti and C. fasciolaris were found only in one rodent.Conclusion: This is the first study to investigate the intestinal parasites in rodents in this area. Among different species identified, some of helminths were reported in new host.

    5. Hypericum perforatum as a cognitive enhancer in rodents: A meta-analysis

      Science.gov (United States)

      Ben-Eliezer, Daniel; Yechiam, Eldad

      2016-01-01

      Considered an antidepressant and anti-anxiety agent, Hypericum perforatum affects multiple neurotransmitters in a non-competitive synergistic manner, and may have nootropic potential. We quantitatively reviewed the pre-clinical literature to examine if there is a cognitive-enhancing effect of H. perforatum in healthy rodents. Additionally, within these studies, we compared the effects observed in intact rodents versus those whose performance has been impaired, mostly through stress manipulations. The meta-analysis incorporated studies that examined the effect of H. perforatum versus placebo on memory indices of task performance. All analyses were based on weighting different studies according to their inverse variance. Thirteen independent studies (published 2000–2014) involving 20 experimental comparisons met our inclusion criteria. The results showed a large positive effect of H. perforatum on cognitive performance for intact, healthy rodents (d = 1.11), though a larger effect emerged for stress-impaired rodents (d = 3.10 for restraint stress). The positive effect on intact rodents was observed in tasks assessing reference memory as well as working memory, and was not moderated by the type of memory or motivation (appetitive versus aversive). Thus, while primarily considered as a medication for depression, H. perforatum shows considerable nootropic potential in rodents. PMID:27762349

    6. Temporal and Spatial Characterization of Gait Pattern in Rodents as an Animal model of Cerebrovascular Lesion

      Directory of Open Access Journals (Sweden)

      Jaison D Cucarián

      2017-09-01

      Full Text Available Animal experimentation is crucial for the advance in the understanding of pathophysiological mechanisms and their application on both clinical diagnosis and neuro-rehabilitation. Particularly, rodent brain lesion is commonly used in the modeling of locomotor, somatosensory and cognitive symptoms. The automated rodent gait analysis has been proposed as a tool for studying locomotor and sensory abilities and its use includes the identification of functional alterations, structural adaptations as well as neuro-rehabilitation mechanisms. From that standpoint, the effectiveness of many therapeutic intervention (i.e. physical exercises has been documented in rodents and humans. The translation from experimental data to clinical conditions requires the continuous collaboration and feedback between researchers and health clinicians looking for the selection of the best rehabilitation protocols obtained from animal research. Here we will show some locomotor alterations, the traditional methods used to assess motor dysfunction and gait abnormalities in rodent models with stroke. The aim of this review is to show some motor deficiencies and some methods used to establish gait disturbances in rodents with cerebrovascular lesion. The review included the search of defined terms (MeSH in PychINFO, Medline and Web of Science, between January 2000 and January 2017. Qualitative and narrative reports, dissertations, end course works and conference resumes were discarded. The review focuses on some clinical signs, their effects on rodent locomotor activity, some methodologies used to create lesion and to study motor function, some assessment methods and some translational aspects.

    7. A higher-taxon approach to rodent conservation priorities for the 21st century

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      Amori, G.

      2003-12-01

      Full Text Available Although rodents are not considered among the most threatened mammals, there is ample historical evidence concerning the vulnerability to extinction of several rodent phylogenetic lineages. Owing to the high number of species, poor taxonomy and the lack of detailed information on population status, the assessment of threat status according to IUCN criteria has still to be considered arbitrary in some cases. Public appreciation is scarce and tends to overlook the ecological role and conservation problems of an order representing about 41 percent of mammalian species. We provide an overview of the most relevant information concerning the conservation status of rodents at the genus, subfamily, and family level. For species¿poor taxa, the importance of distinct populations is highlighted and a splitter approach in taxonomy is adopted. Considering present constraints, strategies for the conservation of rodent diversity must rely mainly on higher taxon and hot-spot approaches. A clear understanding of phyletic relationships among difficult groups -such as Rattus, for instance- is an urgent goal. Even if rodent taxonomy is still unstable, high taxon approach is amply justified from a conservation standpoint as it offers a more subtle overview of the world terrestrial biodiversity than that offered by large mammals. Of the circa 451 living rodent genera, 126 (27,9 %, representing 168 living species, deserve conservation attention according to the present study. About 76 % of genera at risk are monotypic, confirming the danger of losing a considerable amount of phylogenetic distinctiveness.

    8. Relationships between rodent white adipose fat pads and human white adipose fat depots

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      Daniella E. Chusyd

      2016-04-01

      Full Text Available The objective of this review was to compare and contrast the physiological and metabolic profiles of rodent white adipose fat pads with white adipose fat depots in humans. Human fat distribution and its metabolic consequences have received extensive attention, but much of what has been tested in translational research has relied heavily on rodents. Unfortunately, the validity of using rodent fat pads as a model of human adiposity has received less attention. There is a surprisingly lack of studies demonstrating an analogous relationship between rodent and human adiposity on obesity-related comorbidities. Therefore, we aimed to compare known similarities and disparities in terms of white adipose tissue development and distribution, sexual dimorphism, weight loss, adipokine secretion, and aging. While the literature supports the notion that many similarities exist between rodents and humans, notable differences emerge related to fat deposition and function of white adipose tissue. Thus, further research is warranted to more carefully define the strengths and limitations of rodent white adipose tissue as a model for humans, with a particular emphasis on comparable fat depots, such as mesenteric fat.

    9. Serological Survey of Zoonotic Viruses in Invasive and Native Commensal Rodents in Senegal, West Africa.

      Science.gov (United States)

      Diagne, Christophe A; Charbonnel, Nathalie; Henttonen, Heikki; Sironen, Tarja; Brouat, Carine

      2017-10-01

      Increasing studies on rodent-borne diseases still highlight the major role of rodents as reservoirs of numerous zoonoses of which the frequency is likely to increase worldwide as a result of accelerated anthropogenic changes, including biological invasions. Such a situation makes pathogen detection in rodent populations important, especially in the context of developing countries characterized by high infectious disease burden. Here, we used indirect fluorescent antibody tests to describe the circulation of potentially zoonotic viruses in both invasive (Mus musculus domesticus and Rattus rattus) and native (Mastomys erythroleucus and Mastomys natalensis) murine rodent populations in Senegal (West Africa). Of the 672 rodents tested, we reported 22 seropositive tests for Hantavirus, Orthopoxvirus, and Mammarenavirus genera, and no evidence of viral coinfection. This study is the first to report serological detection of Orthopoxvirus in rodents from Senegal, Mammarenavirus in R. rattus from Africa, and Hantavirus in M. m. domesticus and in M. erythroleucus. Further specific identification of the viral agents highlighted here is urgently needed for crucial public health concerns.

    10. A comparison of bats and rodents as reservoirs of zoonotic viruses: are bats special?

      Science.gov (United States)

      Luis, Angela D.; Hayman, David T. S.; O'Shea, Thomas J.; Cryan, Paul M.; Gilbert, Amy T.; Pulliam, Juliet R. C.; Mills, James N.; Timonin, Mary E.; Willis, Craig K. R.; Cunningham, Andrew A.; Fooks, Anthony R.; Rupprecht, Charles E.; Wood, James L. N.; Webb, Colleen T.

      2013-01-01

      Bats are the natural reservoirs of a number of high-impact viral zoonoses. We present a quantitative analysis to address the hypothesis that bats are unique in their propensity to host zoonotic viruses based on a comparison with rodents, another important host order. We found that bats indeed host more zoonotic viruses per species than rodents, and we identified life-history and ecological factors that promote zoonotic viral richness. More zoonotic viruses are hosted by species whose distributions overlap with a greater number of other species in the same taxonomic order (sympatry). Specifically in bats, there was evidence for increased zoonotic viral richness in species with smaller litters (one young), greater longevity and more litters per year. Furthermore, our results point to a new hypothesis to explain in part why bats host more zoonotic viruses per species: the stronger effect of sympatry in bats and more viruses shared between bat species suggests that interspecific transmission is more prevalent among bats than among rodents. Although bats host more zoonotic viruses per species, the total number of zoonotic viruses identified in bats (61) was lower than in rodents (68), a result of there being approximately twice the number of rodent species as bat species. Therefore, rodents should still be a serious concern as reservoirs of emerging viruses. These findings shed light on disease emergence and perpetuation mechanisms and may help lead to a predictive framework for identifying future emerging infectious virus reservoirs. PMID:23378666

    11. Wild Rodents as Experimental Intermediate Hosts of Lagochilascaris minor Leiper, 1909

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      Julieta Machado Paçô

      1999-07-01

      Full Text Available A total of 25 specimens of Cavia porcellus (guinea pig, 5 Dasyprocta agouti (agouti, and 22 Calomys callosus (vesper mice were inoculated with infective eggs of Lagochilascaris minor. The inoculum was prepared with embryonated eggs and orally administered to each individual animal through an esophagus probe. In parallel, 100 specimens of Felis catus domesticus were individually fed with 55-70 nodules containing 3rd-stage larvae encysted in tissues of infected rodents. Animals were examined and necropsied at different time intervals. The migration and encystment of L3 larva was observed in viscera, skeletal muscle, adipose and subcutaneous tissues from all rodents. Adult worms localized at abscesses in the cervical region, rhino, and oropharynx were recovered from domestic cats inoculated with infected rodent tissues. Through this study we can conclude that: (1 wild rodents act as intermediate hosts, characterizing this ascarid heteroxenic cycle; (2 in natural conditions rodents could possibly act as either intermediate hosts or paratenic hosts of Lagochilascaris minor; (3 despite the occurrence of an auto-infecting cycle, in prime-infection of felines (definite hosts the cycle is only completed when intermediate hosts are provided; and (4 in the wild, rodents could serve as a source of infection for humans as they are frequently used as food in regions with the highest incidence of human lagochilascariasis.

    12. Study of hantavirus infection in captive breed colonies of wild rodents

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      RC Oliveira

      2004-10-01

      Full Text Available Wild sigmondontine rodents are known to be the reservoir of several serotypes of New World hantaviruses. The mechanism of viral transmission is by aerosol inhalation of the excreta from infected rodents. Considering that the captive breed colonies of various wild mammals may present a potencial risk for hantaviral transmission, we examined 85 speciemens of Thrichomys spp. (Echimyidae and 17 speciemens of Nectomys squamipes (Sigmodontinae from our colony for the presence of hantavirus infections. Blood samples were assayed for the presence of antibodies to Andes nucleocapsid antigen using enzyme-linked immunosorbent assay (ELISA. Additionally, serum samples from workers previously exposed to wild rodents, in the laboratories where the study was conducted, were also tested by ELISA to investigate prevalence of anti-hantavirus IgG antibodies. All blood samples were negative for hantavirus antibodies. Although these results suggest that those rodent's colonies are hantavirus free, the work emphasizes the need for hantavirus serological monitoring in wild colonized rodents and secure handling potentially infected rodents as important biosafety measures.

    13. Intestinal Helminths in Different Species of Rodents in North Khorasan Province, Northeast of Iran.

      Science.gov (United States)

      Arzamani, Kourosh; Salehi, Mitra; Mobedi, Iraj; Adinezade, Amir; Hasanpour, Hamid; Alavinia, Mohammad; Darvish, Jamshid; Shirzadi, Mohammad Reza; Mohammadi, Zeinolabedin

      2017-01-01

      Rodents are an important source of zoonotic diseases for human. The aim of this study was to determine the infectivity of rodents with intestinal helminths in North Khorasan Province, Iran. One hundred and thirteen rodents were collected using different collection methods such as kill and live traps, digging of their burrow, filling of their hiding places with water and hand net during 2011-2013. Their alimentary canals were removed in the laboratory and helminths were determined in the department of parasitology, Tehran University of Medical Sciences. Thirteen species of helminths parasites were found in 13 species of rodents, including Aspiculuris tetraptera, Hymenolepis diminuta, Nippostrongylus brasiliensis, Protospirura Seurat, Rictolaria ratti, Skrjabinitaenia lobata, Streptopharagus kuntzi, Syphacia obvelata, Taenia taeniaeformis, Trichuris muris, Cysticercus fasciolaris, Acanthocephal. spp and Trichuris spp . Some of them were reported for the first time in new host in Iran. S. obvelata and A. tetraptera were the most frequent parasites and P. Seurat, R. ratti and C. fasciolaris were found only in one rodent. This is the first study to investigate the intestinal parasites in rodents in this area. Among different species identified, some of helminths were reported in new host.

    14. Zoonotic pathogens in Atlantic Forest wild rodents in Brazil: Bartonella and Coxiella infections.

      Science.gov (United States)

      Rozental, Tatiana; Ferreira, Michelle Santos; Guterres, Alexandro; Mares-Guia, Maria Angélica; Teixeira, Bernardo R; Gonçalves, Jonathan; Bonvicino, Cibele Rodrigues; D'Andrea, Paulo Sergio; de Lemos, Elba Regina Sampaio

      2017-04-01

      Zoonotic pathogens comprise a significant and increasing fraction of all emerging and re-emerging infectious diseases that plague humans. Identifying host species is one of the keys to controlling emerging infectious diseases. From March 2007 until April 2012, we collected a total of 131 wild rodents in eight municipalities of Rio de Janeiro, Brazil. We investigated these rodents for infection with Coxiella burnetii, Bartonella spp. and Rickettsia spp. In total, 22.1% (29/131) of the rodents were infected by at least one pathogen; co-infection was detected in 1.5% (2/131) of rodents. Coxiella burnetii was detected in 4.6% (6/131) of the wild animals, 17.6% of the rodents harbored Bartonella spp. No cases of Rickettsia were identified. Bartonella doshiae and Bartonella vinsonii were the species found on the wild mammals. This report is the first to note C. burnetii, B. doshiae and B. vinsonii natural infections in Atlantic Forest wild rodents in Brazil. Our work highlights the potential risk of transmission to humans, since most of the infected specimens belong to generalist species that live near human dwellings. Copyright © 2017 Elsevier B.V. All rights reserved.

    15. Improved protocols for the study of urinary electrolyte excretion and blood pressure in rodents: use of gel food and stepwise changes in diet composition.

      Science.gov (United States)

      Nizar, Jonathan M; Bouby, Nadine; Bankir, Lise; Bhalla, Vivek

      2018-06-01

      Many experimental protocols in rodents require the comparison of groups that are fed different diets. Changes in dietary electrolyte and/or fat content can influence food intake, which can potentially introduce bias or confound the results. Unpalatable diets slow growth or cause weight loss, which is exacerbated by housing the animals in individual metabolic cages or by surgery. For balance studies in mice, small changes in body weight and food intake and low urinary flow can amplify these challenges. Powder food can be administered as gel with the addition of a desired amount of water, electrolytes, drugs (if any), and a small amount of agar. We describe here how the use of gel food to vary water, Na, K, and fat content can reduce weight loss and improve reproducibility of intake, urinary excretion, and blood pressure in rodents. In addition, mild food restriction reduces the interindividual variability and intergroup differences in food intake and associated variables, thus improving the statistical power of an experiment. Finally, we also demonstrate the advantages of using gel food for weight-based drug dosing. These protocols can improve the accuracy and reproducibility of experimental data where dietary manipulations are needed and are especially advisable in rodent studies related to water balance, obesity, and blood pressure.

    16. The role of rodents in the ecology of Ixodes ricinus and associated pathogens in Central and Eastern Europe.

      Science.gov (United States)

      Mihalca, Andrei D; Sándor, Attila D

      2013-01-01

      Rodents comprise more species than any other mammal order. Most rodents are considered keystone species in their ecological communities, hence the survival of many other species in the ecosystem depend on them. From medical point of view, this is particularly important for rodent-dependent pathogens. In the particular case of tick-borne diseases, rodents are important as hosts for vector ticks and as reservoir hosts (Lyme borreliosis, human granulocytic anaplasmosis, Crimean-Congo hemorrhagic fever, Tick-borne relapsing fevers, tick-borne rickettsioses, babesiosis). Community and population ecology of rodents was shown to be correlated with disease ecology in the case of many tick-borne diseases. In Eastern Europe, several adult hard-tick species use rodents as their principal hosts: Ixodes apronophorus, I. crenulatus, I. laguri, I. redikorzevi, I. trianguliceps. However, the majority of ticks feeding on rodents are immature stages of ticks which as adults are parasitic on larger mammals. Larvae and nymphs of Ixodes ricinus, the most abundant and medically important tick from Europe, are commonly found on rodents. This is particularly important, as many rodents are synanthropic and, together with other micromammals and birds are often the only available natural hosts for ticks in urban environments. This work reviews the correlated ecology of rodents and I. ricinus.

    17. 1156-IJBCS-Article-Marie Pare

      African Journals Online (AJOL)

      hp

      forage plant used in liquid waste treatment in Cameroon: opportunity to link .... ruminant production, the tropical regions are ... In addition, protein content and digestibility of ..... change in feeding behavior of the animals in ..... Guinea pigs.

    18. The peculiarities of the masticator muscles in rodents

      Directory of Open Access Journals (Sweden)

      C. Spataru

      2013-06-01

      Full Text Available Comparative research concerning masticatory musculature in squirrel, muskrat and rabbit, take into account the emphasizing and morphofunctional interpretation of the osteomuscular particularities involved in the prehension and mastication processes. The development of the coronoid process on the muskrat and squirrel demonstrates the growing of the force when raising the mandible by increasing the action force attached to the temporal muscle, with insertion on the coronoid process. In comparison with that, in the case of rabbits, both the coronoid process and the temporal muscle are reduced. From a philogenetic point of view, it has been found that the species that have the articular condyle lowered at or under the level of the dental tables (carnivores present a greater pressure force between the dental tables. Analyzing this aspect of the rodents taken into discussion, we noticed the lowering of the articular condyle up to the inferior molars' plane, in the case of squirrels and muskrats, but through obliquity, namely through cranial caudal and dorsoventral movement. This peculiarity is emphasized through the analysis of the angle formed by the axis of the mandible recurved branch (passing through the mandibular condyle with the axis of the horizontal branch of the mandible, where it was noticed that along with the increase in the angle formed by the two axes, which becomes an obtuse 160 degree angle on the squirrel and 130 degrees on the muskrat, there is also a lowering of the articular condyle up to the molar level, while in the case of carnivores, the lowering of the condyle is done without the modification of the angle between the two axes, which measures approximately 90 degrees.

    19. Chronic fluoxetine treatment increases daytime melatonin synthesis in the rodent

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      Gillian W Reierson

      2009-09-01

      Full Text Available Gillian W Reierson, Claudio A Mastronardi, Julio Licinio, Ma-Li WongCenter on Pharmacogenomics, Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, USAAbstract: Circadian rhythm disturbances can occur as part of the clinical symptoms of major depressive disorder and have been found to resolve with antidepressant therapy. The pineal gland is relevant to circadian rhythms as it secretes the hormone melatonin following activation of the cyclic adenosine monophosphate (cAMP signaling cascade and of arylalkylamine N-acetyltransferase (AA-NAT, the rate-limiting enzyme for its synthesis. Cyclic AMP is synthesized by adenylate cyclases (AC and degraded by phosphodiesterases (PDEs. Little is known about the contribution of the PDE system to antidepressant-induced alterations in pineal cAMP signaling and melatonin synthesis. In the present study we used enzyme immunoassay to measure plasma melatonin levels and pineal cAMP levels and as well as quantitative real-time polymerase chain reaction to measure pineal expression of PDE, AC, and AA-NAT genes in rats chronically treated with the prototypic antidepressant fluoxetine. We found elevated melatonin synthesis with increased pineal AA-NAT gene expression and daytime plasma melatonin levels and downregulated cAMP signaling with increased PDE and unchanged AC pineal gene expression, and decreased content of pineal cAMP. We conclude that chronic fluoxetine treatment increases daytime plasma melatonin and pineal AA-NAT gene expression despite downregulated pineal cAMP signaling in the rodent.Keywords: antidepressant, melatonin, pineal, nucleotides, cyclic, phosphodiesterase, rat

    20. STRESS INDUCED OBESITY: LESSONS FROM RODENT MODELS OF STRESS

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      Zachary Robert Patterson

      2013-07-01

      Full Text Available Stress is defined as the behavioral and physiological responses generated in the face of, or in anticipation of, a perceived threat. The stress response involves activation of the sympathetic nervous system and recruitment of the hypothalamic-pituitary-adrenal (HPA axis. When an organism encounters a stressor (social, physical, etc., these endogenous stress systems are stimulated in order to generate a fight-or-flight response, and manage the stressful situation. As such, an organism is forced to liberate energy resources in attempt to meet the energetic demands posed by the stressor. A change in the energy homeostatic balance is thus required to exploit an appropriate resource and deliver useable energy to the target muscles and tissues involved in the stress response. Acutely, this change in energy homeostasis and the liberation of energy is considered advantageous, as it is required for the survival of the organism. However, when an organism is subjected to a prolonged stressor, as is the case during chronic stress, a continuous irregularity in energy homeostasis is considered detrimental and may lead to the development of metabolic disturbances such as cardiovascular disease, type II diabetes mellitus and obesity. This concept has been studied extensively using animal models, and the neurobiological underpinnings of stress induced metabolic disorders are beginning to surface. However, different animal models of stress continue to produce divergent metabolic phenotypes wherein some animals become anorexic and loose body mass while others increase food intake and body mass and become vulnerable to the development of metabolic disturbances. It remains unclear exactly what factors associated with stress models can be used to predict the metabolic outcome of the organism. This review will explore a variety of rodent stress models and discuss the elements that influence the metabolic outcome in order to further our understanding of stress

    1. Expensive Brains: “Brainy” Rodents have Higher Metabolic Rate

      Science.gov (United States)

      Sobrero, Raúl; May-Collado, Laura J.; Agnarsson, Ingi; Hernández, Cristián E.

      2011-01-01

      Brains are the centers of the nervous system of animals, controlling the organ systems of the body and coordinating responses to changes in the ecological and social environment. The evolution of traits that correlate with cognitive ability, such as relative brain size is thus of broad interest. Brain mass relative to body mass (BM) varies among mammals, and diverse factors have been proposed to explain this variation. A recent study provided evidence that energetics play an important role in brain evolution (Isler and van Schaik, 2006). Using composite phylogenies and data drawn from multiple sources, these authors showed that basal metabolic rate (BMR) correlates with brain mass across mammals. However, no such relationship was found within rodents. Here we re-examined the relationship between BMR and brain mass within Rodentia using a novel species-level phylogeny. Our results are sensitive to parameter evaluation; in particular how species mass is estimated. We detect no pattern when applying an approach used by previous studies, where each species BM is represented by two different numbers, one being the individual that happened to be used for BMR estimates of that species. However, this approach may compromise the analysis. When using a single value of BM for each species, whether representing a single individual, or available species mean, our findings provide evidence that brain mass (independent of BM) and BMR are correlated. These findings are thus consistent with the hypothesis that large brains evolve when the payoff for increased brain mass is greater than the energetic cost they incur. PMID:21811456

    2. Sperm competition, sperm numbers and sperm quality in muroid rodents.

      Science.gov (United States)

      Gómez Montoto, Laura; Magaña, Concepción; Tourmente, Maximiliano; Martín-Coello, Juan; Crespo, Cristina; Luque-Larena, Juan José; Gomendio, Montserrat; Roldan, Eduardo R S

      2011-03-25

      Sperm competition favors increases in relative testes mass and production efficiency, and changes in sperm phenotype that result in faster swimming speeds. However, little is known about its effects on traits that contribute to determine the quality of a whole ejaculate (i.e., proportion of motile, viable, morphologically normal and acrosome intact sperm) and that are key determinants of fertilization success. Two competing hypotheses lead to alternative predictions: (a) sperm quantity and quality traits co-evolve under sperm competition because they play complementary roles in determining ejaculate's competitive ability, or (b) energetic constraints force trade-offs between traits depending on their relevance in providing a competitive advantage. We examined relationships between sperm competition levels, sperm quantity, and traits that determine ejaculate quality, in a comparative study of 18 rodent species using phylogenetically controlled analyses. Total sperm numbers were positively correlated to proportions of normal sperm, acrosome integrity and motile sperm; the latter three were also significantly related among themselves, suggesting no trade-offs between traits. In addition, testes mass corrected for body mass (i.e., relative testes mass), showed a strong association with sperm numbers, and positive significant associations with all sperm traits that determine ejaculate quality with the exception of live sperm. An "overall sperm quality" parameter obtained by principal component analysis (which explained 85% of the variance) was more strongly associated with relative testes mass than any individual quality trait. Overall sperm quality was as strongly associated with relative testes mass as sperm numbers. Thus, sperm quality traits improve under sperm competition in an integrated manner suggesting that a combination of all traits is what makes ejaculates more competitive. In evolutionary terms this implies that a complex network of genetic and

    3. Tick parasites of rodents in Romania: host preferences, community structure and geographical distribution.

      Science.gov (United States)

      Mihalca, Andrei D; Dumitrache, Mirabela O; Sándor, Attila D; Magdaş, Cristian; Oltean, Miruna; Györke, Adriana; Matei, Ioana A; Ionică, Angela; D'Amico, Gianluca; Cozma, Vasile; Gherman, Călin M

      2012-11-21

      Ticks are among the most important vectors of zoonotic diseases in temperate regions of Europe, with widespread distribution and high densities, posing an important medical risk. Most ticks feed on a variety of progressively larger hosts, with a large number of small mammal species typically harbouring primarily the immature stages. However, there are certain Ixodidae that characteristically attack micromammals also during their adult stage. Rodents are widespread hosts of ticks, important vectors and competent reservoirs of tick-borne pathogens. Micromammal-tick associations have been poorly studied in Romania, and our manuscript shows the results of a large scale study on tick infestation epidemiology in rodents from Romania. Rodents were caught using snap-traps in a variety of habitats in Romania, between May 2010 and November 2011. Ticks were individually collected from these rodents and identified to species and development stage. Frequency, mean intensity, prevalence and its 95% confidence intervals were calculated using the EpiInfo 2000 software. A p value of Romania for the presence of ticks. Each collected tick was identified to species level and the following epidemiological parameters were calculated: prevalence, mean intensity and mean abundance. The total number of ticks collected from rodents was 483, with eight species identified: Ixodes ricinus, I. redikorzevi, I. apronophorus, I. trianguliceps, I. laguri, Dermacentor marginatus, Rhipicephalus sanguineus and Haemaphysalis sulcata. The overall prevalence of tick infestation was 29.55%, with a mean intensity of 3.86 and a mean abundance of 1.14. Only two polyspecific infestations were found: I. ricinus + I. redikorzevi and I. ricinus + D. marginatus. Our study showed a relatively high diversity of ticks parasitizing rodents in Romania. The most common tick in rodents was I. ricinus, followed by I. redikorzevi. Certain rodents seem to host a significantly higher number of tick species than others, the

    4. Protozoan Parasites of Rodents and Their Zoonotic Significance in Boyer-Ahmad District, Southwestern Iran

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      Zeinab Seifollahi

      2016-01-01

      Full Text Available Backgrounds. Wild rodents are reservoirs of various zoonotic diseases, such as toxoplasmosis, babesiosis, and leishmaniasis. The current study aimed to assess the protozoan infection of rodents in Boyer-Ahmad district, southwestern Iran. Materials and Methods. A total of 52 rodents were collected from different parts of Boyer-Ahmad district, in Kohgiluyeh and Boyer-Ahmad province, using Sherman live traps. Each rodent was anesthetized with ether, according to the ethics of working with animals, and was dissected. Samples were taken from various tissues and stool samples were collected from the contents of the colon and small intestines. Moreover, 2 to 5 mL of blood was taken from each of the rodents and the sera were examined for anti-Leishmania antibodies, by ELISA, or anti-T. gondii antibodies, by modified agglutination test (MAT. DNA was extracted from brain tissue samples of each rodent and PCR was used to identify the DNA of T. gondii. Results. Of the 52 stool samples of rodents studied by parasitological methods, intestinal protozoa infection was seen in 28 cases (53.8%. From 52 rodents, 19 (36.5% were infected with Trichomonas, 10 (19.2% with Giardia muris, and 11 (21.2% with Entamoeba spp. Also, 10 cases (19.2% were infected with Blastocystis, 3 (5.8% were infected with Chilomastix, 7 (13.5% were infected with Endolimax, 1 (1.9% was infected with Retortamonas, 3 (5.77% were infected with T. gondii, and 6 (11.54% were infected with Trypanosoma lewisi. Antibodies to T. gondii were detected in the sera of 5 (9.61% cases. Results of the molecular study showed T. gondii infection in 3 (5.77% of the rodents. Findings of this study showed that rodents in Kohgiluyeh and Boyer-Ahmad province, southwestern Iran, are infected with several blood and intestinal parasites; some of them might be potential risks to residents and domestic animals in the region.

    5. Fully automated rodent brain MR image processing pipeline on a Midas server: from acquired images to region-based statistics.

      Science.gov (United States)

      Budin, Francois; Hoogstoel, Marion; Reynolds, Patrick; Grauer, Michael; O'Leary-Moore, Shonagh K; Oguz, Ipek

      2013-01-01

      Magnetic resonance imaging (MRI) of rodent brains enables study of the development and the integrity of the brain under certain conditions (alcohol, drugs etc.). However, these images are difficult to analyze for biomedical researchers with limited image processing experience. In this paper we present an image processing pipeline running on a Midas server, a web-based data storage system. It is composed of the following steps: rigid registration, skull-stripping, average computation, average parcellation, parcellation propagation to individual subjects, and computation of region-based statistics on each image. The pipeline is easy to configure and requires very little image processing knowledge. We present results obtained by processing a data set using this pipeline and demonstrate how this pipeline can be used to find differences between populations.

    6. The experience on the use of morphological methods in radioecological monitoring of mouse rodents

      International Nuclear Information System (INIS)

      Materij, L.D.; Ermakova, O.V.

      1996-01-01

      Hysto-cytological and morphometrical methods are recommended for use in radio-ecological monitoring. Morphological studies were carried out on Microtus oeconomus Pull from the 30 km accident zone of the Chernobyl NPP. The micropopulation of vole was exposed to acute irradiation at the beginning of the accident at a dose of about 1 Gy. Later on the exposure transformed into low-background irradiation (external and internal). Tissue analysis for crucial systems made it possible to determine the order of radiation response development in the organism in different vole generations, as well as the formation of steady pathological changes

    7. The role of early life experience and species differences in alcohol intake in microtine rodents.

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      Allison M J Anacker

      Full Text Available Social relationships have important effects on alcohol drinking. There are conflicting reports, however, about whether early-life family structure plays an important role in moderating alcohol use in humans. We have previously modeled social facilitation of alcohol drinking in peers in socially monogamous prairie voles. We have also modeled the effects of family structure on the development of adult social and emotional behaviors. Here we assessed whether alcohol intake would differ in prairie voles reared by both parents compared to those reared by a single mother. We also assessed whether meadow voles, a closely related species that do not form lasting reproductive partnerships, would differ in alcohol drinking or in the effect of social influence on drinking. Prairie voles were reared either bi-parentally (BP or by a single mother (SM. BP- and SM-reared adult prairie voles and BP-reared adult meadow voles were given limited access to a choice between alcohol (10% and water over four days and assessed for drinking behavior in social and non-social drinking environments. While alcohol preference was not different between species, meadow voles drank significantly lower doses than prairie voles. Meadow voles also had significantly higher blood ethanol concentrations than prairie voles after receiving the same dose, suggesting differences in ethanol metabolism. Both species, regardless of rearing condition, consumed more alcohol in the social drinking condition than the non-social condition. Early life family structure did not significantly affect any measure. Greater drinking in the social condition indicates that alcohol intake is influenced similarly in both species by the presence of a peer. While the ability of prairie voles to model humans may be limited, the lack of differences in alcohol drinking in BP- and SM-reared prairie voles lends biological support to human studies demonstrating no effect of single-parenting on alcohol abuse.

    8. Rough-legged buzzards, Arctic foxes and red foxes in a tundra ecosystem without rodents.

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      Ivan Pokrovsky

      Full Text Available Small rodents with multi-annual population cycles strongly influence the dynamics of food webs, and in particular predator-prey interactions, across most of the tundra biome. Rodents are however absent from some arctic islands, and studies on performance of arctic predators under such circumstances may be very instructive since rodent cycles have been predicted to collapse in a warming Arctic. Here we document for the first time how three normally rodent-dependent predator species-rough-legged buzzard, arctic fox and red fox - perform in a low-arctic ecosystem with no rodents. During six years (in 2006-2008 and 2011-2013 we studied diet and breeding performance of these predators in the rodent-free Kolguev Island in Arctic Russia. The rough-legged buzzards, previously known to be a small rodent specialist, have only during the last two decades become established on Kolguev Island. The buzzards successfully breed on the island at stable low density, but with high productivity based on goslings and willow ptarmigan as their main prey - altogether representing a novel ecological situation for this species. Breeding density of arctic fox varied from year to year, but with stable productivity based on mainly geese as prey. The density dynamic of the arctic fox appeared to be correlated with the date of spring arrival of the geese. Red foxes breed regularly on the island but in very low numbers that appear to have been unchanged over a long period - a situation that resemble what has been recently documented from Arctic America. Our study suggests that the three predators found breeding on Kolguev Island possess capacities for shifting to changing circumstances in low-arctic ecosystem as long as other small - medium sized terrestrial herbivores are present in good numbers.

    9. Vision in laboratory rodents-Tools to measure it and implications for behavioral research.

      Science.gov (United States)

      Leinonen, Henri; Tanila, Heikki

      2017-07-29

      Mice and rats are nocturnal mammals and their vision is specialized for detection of motion and contrast in dim light conditions. These species possess a large proportion of UV-sensitive cones in their retinas and the majority of their optic nerve axons target superior colliculus rather than visual cortex. Therefore, it was a widely held belief that laboratory rodents hardly utilize vision during day-time behavior. This dogma is being questioned as accumulating evidence suggests that laboratory rodents are able to perform complex visual functions, such as perceiving subjective contours, and that declined vision may affect their performance in many behavioral tasks. For instance, genetic engineering may have unexpected consequences on vision as mouse models of Alzheimer's and Huntington's diseases have declined visual function. Rodent vision can be tested in numerous ways using operant training or reflex-based behavioral tasks, or alternatively using electrophysiological recordings. In this article, we will first provide a summary of visual system and explain its characteristics unique to rodents. Then, we present well-established techniques to test rodent vision, with an emphasis on pattern vision: visual water test, optomotor reflex test, pattern electroretinography and pattern visual evoked potentials. Finally, we highlight the importance of visual phenotyping in rodents. As the number of genetically engineered rodent models and volume of behavioral testing increase simultaneously, the possibility of visual dysfunctions needs to be addressed. Neglect in this matter potentially leads to crude biases in the field of neuroscience and beyond. Copyright © 2017 Elsevier B.V. All rights reserved.

    10. Occurrence and distribution of Giardia species in wild rodents in Germany.

      Science.gov (United States)

      Helmy, Yosra A; Spierling, Nastasja G; Schmidt, Sabrina; Rosenfeld, Ulrike M; Reil, Daniela; Imholt, Christian; Jacob, Jens; Ulrich, Rainer G; Aebischer, Toni; Klotz, Christian

      2018-03-27

      Giardiasis is an important gastrointestinal parasitic disease in humans and other mammals caused by the protozoan Giardia duodenalis. This species complex is represented by genetically distinct groups (assemblages A-H) with varying zoonotic potential and host preferences. Wild rodents can harbor potentially zoonotic assemblages A and B, and the rodent-specific assemblage G. Other Giardia spp. found in these animals are Giardia muris and Giardia microti. For the latter, only limited information on genetic typing is available. It has been speculated that wild rodents might represent an important reservoir for parasites causing human giardiasis. The aim of this study was to investigate the occurrence and distribution of Giardia spp. and assemblage types in wild rodents from different study sites in Germany. Screening of 577 wild rodents of the genera Apodemus, Microtus and Myodes, sampled at eleven study sites in Germany, revealed a high overall Giardia prevalence. Giardia species determination at the SSU rDNA gene locus revealed that Apodemus mice, depending on species, were predominantly infected with one of two distinct G. muris sequence types. Giardia microti was the predominant parasite species found in voles of the genera Microtus and Myodes. Only a few animals were positive for potentially zoonotic G. duodenalis. Subtyping at the beta-giardin (bg) and glutamine dehydrogenase (gdh) genes strongly supported the existence of different phylogenetic subgroups of G. microti that are preferentially harbored by distinct host species. The present study highlights the preference of G. muris for Apodemus, and G. microti for Microtus and Myodes hosts and argues for a very low prevalence of zoonotic G. duodenalis assemblages in wild rodents in Germany. It also provides evidence that G. muris and G. microti subdivide into several phylogenetically distinguishable subgroups, each of which appears to be preferentially harbored by species of a particular rodent host genus

    11. Occurrence of ectoparasitic arthropods associated with rodents in Hail region northern Saudi Arabia.

      Science.gov (United States)

      Asiry, Khalid A; Fetoh, Badr El-Sabah A

      2014-09-01

      Ectoparasitic arthropods are a diverse element of the Saudi fauna. Due to this, a survey of ectoparasites associated with rodents was conducted as a preliminary study in five districts of Hail region of northern Saudi Arabia for the first time. Ectoparasites extracted from 750 rodents were sampled and identified by recording their frequency of appearance. Results revealed that 1,287 ectoparasites infested 316 of the captured rodent hosts. These ectoparasites parasitized on four species of rodents including three species of rats Rattus rattus rattus, Rattus rattus frugivorus, and Rattus rattus alexandrinus and one species of mouse Acomys dimidiatus (Rodentia: Muridae). The ectoparasites belong to four different groups: ticks, fleas, lice, and mites. Ticks were the highest in the number, while fleas were the lowest among all the extracted ectoparasite groups. The collected ectoparasitic arthropods consisted of seven species. Ticks were of two species: Rhipicephalus turanicus and Rhipicephalus sanguineus (Acari: Ixodidae), fleas were of two species: Xenopsylla cheopis and Xenopsyllus conformis mycerini (Siphonaptera: Pulicidae), lice was a single species: Polyplax serrata (Anoplura: Hoplopleuridae), and mites were of two species: Laelaps nuttali and Laelaps echidninus (Mesostigmata: Laelapidae). The findings of the study showed that the intensity of infestation was varied between rodent host sexes, wherein females had the highest rate of parasitic infestation, and the parasitic index of appearance was very high for one group of parasites (i.e., ticks). The parasitic prevalence was 42.13 % on rodents, and mites were the most prevalent parasite species. Overall, this study was carried out to establish baseline data for ectoparasite-infested rodents in Hail region, Saudi Arabia, and may help for appropriate planning to control zoonotic diseases in this area.

    12. The hip adductor muscle group in caviomorph rodents: anatomy and homology.

      Science.gov (United States)

      García-Esponda, César M; Candela, Adriana M

      2015-06-01

      Anatomical comparative studies including myological data of caviomorph rodents are relatively scarce, leading to a lack of use of muscular features in cladistic and morphofunctional analyses. In rodents, the hip adductor muscles constitute an important group of the hindlimb musculature, having an important function during the beginning of the stance phase. These muscles are subdivided in several distinct ways in the different clades of rodents, making the identification of their homologies hard to establish. In this contribution we provide a detailed description of the anatomical variation of the hip adductor muscle group of different genera of caviomorph rodents and identify the homologies of these muscles in the context of Rodentia. On this basis, we identify the characteristic pattern of the hip adductor muscles in Caviomorpha. Our results indicate that caviomorphs present a singular pattern of the hip adductor musculature that distinguishes them from other groups of rodents. They are characterized by having a single m. adductor brevis that includes solely its genicular part. This muscle, together with the m. gracilis, composes a muscular sheet that is medial to all other muscles of the hip adductor group. Both muscles probably have a synergistic action during locomotion, where the m. adductor brevis reinforces the multiple functions of the m. gracilis in caviomorphs. Mapping of analyzed myological characters in the context of Rodentia indicates that several features are recovered as potential synapomorphies of caviomorphs. Thus, analysis of the myological data described here adds to the current knowledge of caviomorph rodents from anatomical and functional points of view, indicating that this group has features that clearly differentiate them from other rodents. Copyright © 2015 Elsevier GmbH. All rights reserved.

    13. Toxoplasma gondii antibodies in wild rodents and marsupials from the Atlantic Forest, state of São Paulo, Brazil

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      Solange Maria Gennari

      Full Text Available Toxoplasma gondii is a protozoan parasite that infects a large spectrum of warm-blooded animals, including humans. Small rodents and marsupials play an important role in the epidemiology of T. gondii because they are sources of infection for domestic and feral cats. Serum samples from 151 rodents and 48 marsupials, captured in the Atlantic Forest, São Paulo State, southeastern Brazil, were analyzed for the presence of T. gondii antibodies. Antibodies detected by the modified agglutination test (MAT ≥ 25 were found in 8.6% (13/151 of the rodents and 10.4% (5/48 of the marsupials, with titers ranging from 25 to 6400 and from 25 to 3200, respectively for the rodents and marsupials. Three of the eight species of rodents (Akodon spp., Oligoryzomys nigripesand Rattus norvegicus, and one from the four marsupial species (Didelphis aurita presented positive animals. T. gondii was described for the first time in the rodent Oligoryzomys nigripes.

    14. Una Aproximación Relacional a la Violencia Escolar Entre Pares en Adolescentes Chilenos: Perspectiva Adolescente de los Factores Intervinientes A Relational Approach to School Violence Among Peers in Chilean Adolescents: Adolescent Perspective About Intervening Factors

      Directory of Open Access Journals (Sweden)

      Maritgen Potocnjak

      2011-11-01

      Full Text Available El presente estudio aborda la violencia escolar desde la perspectiva de los adolescentes, identificando factores intervinientes en su emergencia. Se utilizó una metodología cualitativa exploratoria enmarcada en la grounded theory, realizando entrevistas individuales y grupales a una muestra intencionada de 28 estudiantes de 11 a 14 años de 3 colegios de la Región Metropolitana de Chile. Los resultados evidencian un distanciamiento entre las lógicas adultas y las necesidades socioafectivas de los estudiantes, lo que favorecería el involucramiento en violencia escolar. La escuela y los profesores no tendrían estrategias efectivas para hacer frente a este fenómeno. Las dinámicas de pares pueden sostener, potenciar o inhibir la violencia, al considerar elementos como el posicionamiento social y las jerarquías internas de la ecología social. El análisis relacional destaca la demanda adolescente por estructura, contención y orientación, planteando que el sistema adulto no satisface de manera adecuada estas necesidades. La violencia cumpliría la función de llamar la atención de los adultos y llenar el espacio de apego social y emocional que se constituye en una necesidad fundamental en esta etapa.The present study approaches school violence from the adolescents' perspective, identifying intervening factors in its emergence. An exploratory qualitative methodology within a grounded theory framework was used, interviewing individually and collectively 28 students of 11 to 14 years old from 3 schools in the Metropolitan Region of Chile. Results show a gap between adult perspectives and students' socioemotional needs, which would favor their involvement in school violence. Schools and teachers do not have effective strategies to face this phenomenon. Peer dynamics can sustain, reinforce, or inhibit violence, through the establishment of social hierarchies within the peer social ecology. The relational analysis highlights the adolescent

    15. Epidemiological distribution of rodents as potent reservoirs for infectious diseases in the provinces of Mazandaran, Gilan and Golestan, northern Iran

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      Behzad Esfandiari

      2017-05-01

      Full Text Available Rodents are mammals that comprise more than 2000 species and approximately 30 families. There are many morphological and ecological differences among them as variations in their shape, size, weight and habitat. In addition to significant economic losses, rodents have a major role in the dissemination of infectious diseases caused by viruses, bacteria, parasites or other micro-organisms. Rodents are important reservoirs of diseases which have been observed in many cities of Iran provinces especially along Caspian Sea border to Alborz Mountain. The aim of this study is to assess the geographical distribution of rodents in three provinces of northern part of Iran as reservoir of potential endemic infectious diseases. Rodents in 10 major parts of each of the three provinces of Mazandaran, Gilan and Golestan, northern Iran were collected and a total of 404 rodents were trapped alive. They were determined by the key characteristics such as gender, genus, species, different locations and topological situation. Statistical analysis was performed to characterize the study sample and to correlate all variables and parameters. The distribution frequencies of three, five and six genera of rodents were identified in Mazandaran, Gilan and Golestan provinces respectively. The overall distribution frequency of eight genera of rodents in the three provinces were identified as Rattus (R. norvegicus (67.3%, R. rattus (13.6%, Apodemus sylvaticus (13.9%, Arvicola (1%, Mus musculus (0.3%, Nesokia indica (2.5%, Cricetulus migrates (0.7% and Rhombomys opimus (0.7%. The results of this study determined the geographic distribution of the rodents in the three northern provinces of Iran. It is indicated the association of various distribution and diversity of rodents with provincial location. The overall distribution frequency of eight genera of rodents was recognized in the above three provinces geographical locations. This study confirms epidemiological distribution of

    16. Calodium (Capillaria hepaticum (Nematoda, Capillariidae in insular small rodent populations

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      Bugmyrin Sergey

      2014-12-01

      Full Text Available The data on the distribution of the nematode Calodium hepaticum (Bancroft 1893 Moravec 1982 (syn.: Capillaria hepatica, Hepaticola hepatica on the islands of Kizhi Archipelago are reported (N 62°00'; E 35°12'. Samples were collected on 18 islands and the mainland part of the Kizhi skerries region in the period from August 2005 till 2014. The method of partial helminthological dissection was applied to 346 specimens of rodents belonging to two species – the bank vole Myodes glareolus Schreber 1780 (301 spm. and the field vole Microtus agrestis Linnaeus 1761 (45 spm.. The prevalence and the abundance index of nematode were 16.6% and 1.1 in M. glareolus and 11.1%; 0.3 in M. agrestis, respectively. The highest prevalence and abundance of C. hepaticum were detected in mature voles. No sex-related differences were found. C. hepaticum was present in 12 of 19 sampling sites. On the islands where the sample number (host individuals was over 15, the highest prevalence and abundance values were 57% and 5.8 spm., respectively. Significant positive coefficients of correlation (Spearman’s and Pearson’s ones between nematode numbers and characteristics of the island were found in the pair «Prevalence – degree of isolation» (0.48 and 0.49. Single-factor analysis of variance showed that the size of the island had some effect on the nematode invasion prevalence and abundance. However, no significant regression relationship between the prevalence and abundance of nematodes and characteristics of an island was revealed by multivariate regression analysis (multiple regression: the coefficient of determination of the regression equation R2 < 0.3, and the regression coefficients were insignificant The reasons for high abundance of C. hepaticum in northern insular ecosystems are discussed. Possible key factors for the stable vitality of the parasite populations are: 1 favourable hydrothermal conditions of the soil in the shore (littoral zone; 2 the

    17. Survey for hantaviruses, tick-borne encephalitis virus, and Rickettsia spp. in small rodents in Croatia.

      Science.gov (United States)

      Svoboda, Petra; Dobler, Gerhard; Markotić, Alemka; Kurolt, Ivan-Christian; Speck, Stephanie; Habuš, Josipa; Vucelja, Marko; Krajinović, Lidija Cvetko; Tadin, Ante; Margaletić, Josip; Essbauer, Sandra

      2014-07-01

      In Croatia, several rodent- and vector-borne agents are endemic and of medical importance. In this study, we investigated hantaviruses and, for the first time, tick-borne encephalitis virus (TBEV) and Rickettsia spp. in small wild rodents from two different sites (mountainous and lowland region) in Croatia. In total, 194 transudate and tissue samples from 170 rodents (A. flavicollis, n=115; A. agrarius, n=2; Myodes glareolus, n=53) were tested for antibodies by indirect immunofluorescence assays (IIFT) and for nucleic acids by conventional (hantaviruses) and real-time RT-/PCRs (TBEV and Rickettsia spp.). A total of 25.5% (24/94) of the rodents from the mountainous area revealed specific antibodies against hantaviruses. In all, 21.3% (20/94) of the samples from the mountainous area and 29.0% (9/31) from the lowland area yielded positive results for either Puumala virus (PUUV) or Dobrava-Belgrade virus (DOBV) using a conventional RT-PCR. All processed samples (n=194) were negative for TBEV by IIFT or real-time RT-PCR. Serological evidence of rickettsial infection was detected in 4.3% (4/94) rodents from the mountainous region. Another 3.2% (3/94) rodents were positive for Rickettsia spp. by real-time PCR. None of the rodents (n=76) from the lowland area were positive for Rickettsia spp. by real-time PCR. Dual infection of PUUV and Rickettsia spp. was found in one M. glareolus from the mountainous area by RT-PCR and real-time PCR, respectively. To our knowledge, this is the first detection of Rickettsia spp. in small rodents from Croatia. Phylogenetic analyses of S- and M-segment sequences obtained from the two study sites revealed well-supported subgroups in Croatian PUUV and DOBV. Although somewhat limited, our data showed occurrence and prevalence of PUUV, DOBV, and rickettsiae in Croatia. Further studies are warranted to confirm these data and to determine the Rickettsia species present in rodents in these areas.

    18. LATE PLEISTOCENE RODENTS (MAMMALIA: RODENTIA FROM THE BARANICA CAVE NEAR KNJAZEVAC (EASTERN SERBIA: SYSTEMATICS AND PALAEOECOLOGY

      Directory of Open Access Journals (Sweden)

      KATARINA BOGICEVIC

      2011-07-01

      Full Text Available Baranica is a cave in the Balkan mountain range in the eastern part of Serbia. It contains four layers of sediments of Quaternary age. The Upper Pleistocene deposits (layers 2-4 have yielded a rich and diverse assemblage of vertebrate fauna, including fish, amphibians, reptiles, birds, and small and large mammals. In this work, preliminary results of a study of the rodent fauna from the Upper Pleistocene deposits of the Baranica Cave (Knjazevac, eastern Serbia are presented. The fossil material comes from the 1995 archaeological excavation. The remains of 10 rodent species are described herein: Spermophilus cf. citelloides, Castor fiber, Sicista subtilis, Cricetulus migratorius, Cricetus cricetus, Mesocricetus newtoni, Apodemus ex gr. sylvaticus-flavicollis, Spalax leucodon, Dryomys nitedula, and Muscardinus avellanarius. Along with eight vole species, this makes altogether 18 species of rodents found in this locality. Both layers 2 and 4 (layer 3 is very poor in fossils have yielded a rodent fauna typical for the cold periods of the Late Pleistocene on the Balkan Peninsula, with a prevalence of open and steppe inhabitants, but some forest dwellers were also present. The assemblages from these layers are similar, but there are some differences in the composition of the fauna, which may indicate a slight shift towards drier conditions. They have also been compared to rodent associations from some Serbian and Bulgarian localities of the same age and their similarities and differences are discussed. SHORT NOTE-NOTA BREVE

    19. Brain development in rodents and humans: Identifying benchmarks of maturation and vulnerability to injury across species

      Science.gov (United States)

      Semple, Bridgette D.; Blomgren, Klas; Gimlin, Kayleen; Ferriero, Donna M.; Noble-Haeusslein, Linda J.

      2013-01-01

      Hypoxic-ischemic and traumatic brain injuries are leading causes of long-term mortality and disability in infants and children. Although several preclinical models using rodents of different ages have been developed, species differences in the timing of key brain maturation events can render comparisons of vulnerability and regenerative capacities difficult to interpret. Traditional models of developmental brain injury have utilized rodents at postnatal day 7–10 as being roughly equivalent to a term human infant, based historically on the measurement of post-mortem brain weights during the 1970s. Here we will examine fundamental brain development processes that occur in both rodents and humans, to delineate a comparable time course of postnatal brain development across species. We consider the timing of neurogenesis, synaptogenesis, gliogenesis, oligodendrocyte maturation and age-dependent behaviors that coincide with developmentally regulated molecular and biochemical changes. In general, while the time scale is considerably different, the sequence of key events in brain maturation is largely consistent between humans and rodents. Further, there are distinct parallels in regional vulnerability as well as functional consequences in response to brain injuries. With a focus on developmental hypoxicischemic encephalopathy and traumatic brain injury, this review offers guidelines for researchers when considering the most appropriate rodent age for the developmental stage or process of interest to approximate human brain development. PMID:23583307

    20. Prevalence and genetic diversity of Bartonella strains in rodents from northwestern Mexico.

      Science.gov (United States)

      Rubio, André V; Ávila-Flores, Rafael; Osikowicz, Lynn M; Bai, Ying; Suzán, Gerardo; Kosoy, Michael Y

      2014-12-01

      Bartonella infections were investigated in wild rodents from northwestern Chihuahua, Mexico. A total of 489 rodents belonging to 14 species were surveyed in four areas. Bartonella bacteria were cultured from 50.1% of rodent samples (245/489). Infection rates ranged from 0% to 83.3% per rodent species, with no significant difference between sites except for Cynomys ludovicianus. Phylogenetic analyses of the citrate synthase gene (gltA) of the Bartonella isolates revealed 23 genetic variants (15 novel and 8 previously described), clustering into five phylogroups. Three phylogroups were associated with Bartonella vinsonii subsp. vinsonii, B. vinsonii subsp. arupensis, and B. washoensis, respectively. The other two phylogroups were not genetically related to any known Bartonella species. The genetic variants and phylogenetic groups exhibited a high degree of host specificity, mainly at the genus and family levels. This is the first study that describes the genetic diversity of Bartonella strains in wild rodents from Mexico. Considering that some variants found in this study are associated with Bartonella species that have been reported as zoonotic, more investigations are needed to further understand the ecology of Bartonella species in Mexican wildlife and their implications for human health.

    1. Genotyping and subtyping of Giardia and Cryptosporidium isolates from commensal rodents in China.

      Science.gov (United States)

      Zhao, Z; Wang, R; Zhao, W; Qi, M; Zhao, J; Zhang, L; Li, J; Liu, A

      2015-05-01

      Cryptosporidium and Giardia are two important zoonotic intestinal parasites responsible for diarrhoea in humans and other animals worldwide. Rodents, as reservoirs or carriers of Cryptosporidium and Giardia, are abundant and globally widespread. In the present study, we collected 232 fecal specimens from commensal rodents captured in animal farms and farm neighbourhoods in China. We collected 33 Asian house rats, 168 brown rats and 31 house mice. 6.0% (14/232) and 8.2% (19/232) of these rodents were microscopy-positive for Giardia cysts and Cryptosporidium oocysts, respectively. All 14 Giardia isolates were identified as Giardia duodenalis assemblage G at a minimum of one or maximum of three gene loci (tpi, gdh and bg). By small subunit rRNA (SSU rRNA) gene sequencing, Cryptosporidium parvum (n = 12) and Cryptosporidium muris (n = 7) were identified. The gp60 gene encoding the 60-kDa glycoprotein was successfully amplified and sequenced in nine C. parvum isolates, all of which belonged to the IIdA15G1 subtype. Observation of the same IIdA15G1 subtype in humans (previously) and in rodents (here) suggests that rodents infected with Cryptosporidium have the potential to transmit cryptosporidiosis to humans.

    2. Spontaneous expression of magnetic compass orientation in an epigeic rodent: the bank vole, Clethrionomys glareolus

      Science.gov (United States)

      Oliveriusová, Ludmila; Němec, Pavel; Pavelková, Zuzana; Sedláček, František

      2014-07-01

      Magnetoreception has been convincingly demonstrated in only a few mammalian species. Among rodents, magnetic compass orientation has been documented in four species of subterranean mole rats and two epigeic (i.e. active above ground) species—the Siberian hamster and the C57BL/6J mouse. The mole rats use the magnetic field azimuth to determine compass heading; their directional preference is spontaneous and unimodal, and their magnetic compass is magnetite-mediated. By contrast, the primary component of orientation response is learned in the hamster and the mouse, but both species also exhibit a weak spontaneous bimodal preference in the natural magnetic field. To determine whether the magnetic compass of wild epigeic rodents features the same functional properties as that of laboratory rodents, we investigated magnetic compass orientation in the bank vole Clethrionomys glareolus (Cricetidae, Rodentia). The voles exhibited a robust spontaneous bimodal directional preference, i.e. built nests and slept preferentially along the north-south axis, and deflected their directional preference according to a shift in the direction of magnetic north, clearly indicating that they were deriving directional information from the magnetic field. Thus, bimodal, axially symmetrical directional choice seems to be a common feature shared by epigeic rodents. However, spontaneous directional preference in the bank vole appeared to be more pronounced than that reported in the hamster and the mouse. These findings suggest that bank voles are well suited for future studies investigating the adaptive significance and mechanisms of magnetic orientation in epigeic rodents.

    3. Comparison of food hoarding of two sympatric rodent species under interspecific competition.

      Science.gov (United States)

      Zhang, Yi-Feng; Tong, Lei; Ji, Wei-Hong; Lu, Ji-Qi

      2013-01-01

      Competition can greatly affect the food hoarding strategies of rodents and the fate of seeds hoarded. In order to understand the influence of interspecific competition on food caching behavior of sympatric rodents, we investigated food hoarding patterns of two sympatric rodent species, buff-breasted rat (Rattus flavipectus) and Chinese white-bellied rat (Niviventor confucianus), and compared their responses and adjustment in hoarding behavior under interspecific competition. The results showed that: (1) the buff-breasted rat larder hoarded seeds only, while Chinese white-bellied rat hoarded seeds in both larder and scatter forms; (2) two species of rodents both larder hoarded more seeds when competitors were present; and (3) the Chinese white-bellied rats adjusted their seed hoarding from scatter to larder when competitors were introduced, which reduced the seed availability. Therefore, we concluded that rodents would adjust their food hoarding strategy when interspecific competitors were present, and this may produce a different effect on the fate of seeds and the recruitment of plants. This article is part of a Special Issue entitled: insert SI title. Copyright © 2012. Published by Elsevier B.V.

    4. Influencias del apego a la madre en el vínculo con los pares en la adolescencia: Diferencias entre una muestra femenina clínica y no clínica Influences of mother attachment into peer relationship during adolescence: Difference between a clinical and non-clinical female sample

      Directory of Open Access Journals (Sweden)

      Verónica C. Vega

      2011-12-01

      Full Text Available Este trabajo se propone indagar tipos de apego a madre y pares en 83 mujeres de 12 a 18 años (Media: 14,63 años, DS 1,20 con Trastornos de la Conducta Alimentaria (n=30 y sin ellos (n=53 y analizar si el tipo de apego a madre se repite en pares. Se utilizó durante la fase clínica de un estudio bietápico (UBACyT 2008-2010, el Inventario de Apego a Padres y Pares (IPPA, Armsden & Greenberg 1987. Resultados: Los grupos clínico y control se diferencian significativamente en el apego a la madre (p The present study examines attachment types to mother and peer in eighty-three women of 12 -18 years old (Media:14,63 years, SD 1,20 with Eating Disorders (n=30 and without them (n=53. In order to research repeated tendencies in types of attachment to mother and peer, in 2009, the Inventory of Parent and Peer Attachment (IPPA, Armsden & Greenberg 1987 was self-reported during the clinical phase of a two phases study (UBACyT 2008-2010. Results: Clinical and control groups present significantly differences in mother scale (p < .001, but marginal ones in peer scale. At the same time, inluences of mother attachment into peers´ were found. Conclusions: Results conirm the ethio-pathogenic relationship between mother-daughter in eating disorders but even there are tendencies repeated in both attachment mother-daughter, statistical indings are not enough to assure that insecure attachment with mother replicates with peer. Same study in a bigger sample should be done to conirm so.

    5. Social housing of non-rodents during cardiovascular recordings in safety pharmacology and toxicology studies.

      Science.gov (United States)

      Prior, Helen; Bottomley, Anna; Champéroux, Pascal; Cordes, Jason; Delpy, Eric; Dybdal, Noel; Edmunds, Nick; Engwall, Mike; Foley, Mike; Hoffmann, Michael; Kaiser, Robert; Meecham, Ken; Milano, Stéphane; Milne, Aileen; Nelson, Rick; Roche, Brian; Valentin, Jean-Pierre; Ward, Gemma; Chapman, Kathryn

      2016-01-01

      The Safety Pharmacology Society (SPS) and National Centre for the Replacement, Refinement & Reduction of Animals in Research (NC3Rs) conducted a survey and workshop in 2015 to define current industry practices relating to housing of non-rodents during telemetry recordings in safety pharmacology and toxicology studies. The aim was to share experiences, canvas opinion on the study procedures/designs that could be used and explore the barriers to social housing. Thirty-nine sites, either running studies (Sponsors or Contract Research Organisations, CROs) and/or outsourcing work responded to the survey (51% from Europe; 41% from USA). During safety pharmacology studies, 84, 67 and 100% of respondents socially house dogs, minipigs and non-human primates (NHPs) respectively on non-recording days. However, on recording days 20, 20 and 33% of respondents socially house the animals, respectively. The main barriers for social housing were limitations in the recording equipment used, study design and animal temperament/activity. During toxicology studies, 94, 100 and 100% of respondents socially house dogs, minipigs and NHPs respectively on non-recording days. However, on recording days 31, 25 and 50% of respondents socially house the animals, respectively. The main barriers for social housing were risk of damage to and limitations in the recording equipment used, food consumption recording and temperament/activity of the animals. Although the majority of the industry does not yet socially house animals during telemetry recordings in safety pharmacology and toxicology studies, there is support to implement this refinement. Continued discussions, sharing of best practice and data from companies already socially housing, combined with technology improvements and investments in infrastructure are required to maintain the forward momentum of this refinement across the industry. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

    6. The traveling salesrat: insights into the dynamics of efficient spatial navigation in the rodent

      Science.gov (United States)

      Watkins de Jong, Laurel; Gereke, Brian; Martin, Gerard M.; Fellous, Jean-Marc

      2011-10-01

      Rodent spatial navigation requires the dynamic evaluation of multiple sources of information, including visual cues, self-motion signals and reward signals. The nature of the evaluation, its dynamics and the relative weighting of the multiple information streams are largely unknown and have generated many hypotheses in the field of robotics. We use the framework of the traveling salesperson problem (TSP) to study how this evaluation may be achieved. The TSP is a classical artificial intelligence NP-hard problem that requires an agent to visit a fixed set of locations once, minimizing the total distance traveled. We show that after a few trials, rats converge on a short route between rewarded food cups. We propose that this route emerges from a series of local decisions that are derived from weighing information embedded in the context of the task. We study the relative weighting of spatial and reward information and establish that, in the conditions of this experiment, when the contingencies are not in conflict, rats choose the spatial or reward optimal solution. There was a trend toward a preference for space when the contingencies were in conflict. We also show that the spatial decision about which cup to go to next is biased by the orientation of the animal. Reward contingencies are also shown to significantly and dynamically modulate the decision-making process. This paradigm will allow for further neurophysiological studies aimed at understanding the synergistic role of brain areas involved in planning, reward processing and spatial navigation. These insights will in turn suggest new neural-like architectures for the control of mobile autonomous robots.

    7. A novel approach to adenine-induced chronic kidney disease associated anemia in rodents.

      Directory of Open Access Journals (Sweden)

      Asadur Rahman

      Full Text Available To date, good experimental animal models of renal anemia are not available. Therefore, the purpose of this study was to establish a novel approach to induce chronic kidney disease (CKD with severe anemia by oral administration of adenine in rodents. Adenine was administered to 6-week-old male C57BL/6 mice (25 and 50 mg/kg body weight by oral gavage daily for 28 days. Serum creatinine and BUN as well as hematocrit, hemoglobin (Hb and plasma erythropoietin (EPO levels were monitored to assess renal function and anemia, respectively. Adenine at 25 mg/kg for 28 days slightly increased plasma creatinine levels, but did not induce anemia. In contrast, 50 mg/kg of adenine daily for 28 days showed severe renal dysfunction (plasma creatinine 1.9 ± 0.10 mg/dL and anemia (hematocrit 36.5 ± 1.0% and EPO 28 ± 2.4 pg/mL as compared with vehicle-treated mice (0.4 ± 0.02 mg/dL, 49.6 ± 1.6% and 61 ± 4.0 pg/mL, respectively. At the end of experiment, level of Hb also significantly reduced in 50 mg/kg adenine administration group. Remarkable histological changes of kidney tissues characterized by interstitial fibrosis and cystic appearance in tubules were observed in 50 mg/kg of adenine treatment group. These results have demonstrated that oral dosing with adenine at 50 mg/kg for 28 days is suitable to induce a stable anemia associated with CKD in mice.

    8. Feeding a diet devoid of choline to lactating rodents restricts growth and lymphocyte development in offspring.

      Science.gov (United States)

      Lewis, E D; Goruk, S; Richard, C; Dellschaft, N S; Curtis, J M; Jacobs, R L; Field, C J

      2016-09-01

      The nutrient choline is necessary for membrane synthesis and methyl donation, with increased requirements during lactation. The majority of immune development occurs postnatally, but the importance of choline supply for immune development during this critical period is unknown. The objective of this study was to determine the importance of maternal supply of choline during suckling on immune function in their offspring among rodents. At parturition, Sprague-Dawley dams were randomised to either a choline-devoid (ChD; n 7) or choline-sufficient (ChS, 1 g/kg choline; n 10) diet with their offspring euthanised at 3 weeks of age. In a second experiment, offspring were weaned to a ChS diet until 10 weeks of age (ChD-ChS, n 5 and ChS-ChS, n 9). Splenocytes were isolated, and parameters of immune function were measured. The ChD offspring received less choline in breast milk and had lower final body and organ weight compared with ChS offspring (P<0·05), but this effect disappeared by week 10 with choline supplementation from weaning. ChD offspring had a higher proportion of T cells expressing activation markers (CD71 or CD28) and a lower proportion of total B cells (CD45RA+) and responded less to T cell stimulation (lower stimulation index and less IFN-γ production) ex vivo (P<0·05). ChD-ChS offspring had a lower proportion of total and activated CD4+ T cells, and produced less IL-6 after mitogen stimulation compared with cells from ChS-ChS (P<0·05). Our study suggests that choline is required in the suckling diet to facilitate immune development, and choline deprivation during this critical period has lasting effects on T cell function later in life.

    9. Dietary restriction of rodents decreases aging rate without affecting initial mortality rate -- a meta-analysis.

      Science.gov (United States)

      Simons, Mirre J P; Koch, Wouter; Verhulst, Simon

      2013-06-01

      Dietary restriction (DR) extends lifespan in multiple species from various taxa. This effect can arise via two distinct but not mutually exclusive ways: a change in aging rate and/or vulnerability to the aging process (i.e. initial mortality rate). When DR affects vulnerability, this lowers mortality instantly, whereas a change in aging rate will gradually lower mortality risk over time. Unraveling how DR extends lifespan is of interest because it may guide toward understanding the mechanism(s) mediating lifespan extension and also has practical implications for the application of DR. We reanalyzed published survival data from 82 pairs of survival curves from DR experiments in rats and mice by fitting Gompertz and also Gompertz-Makeham models. The addition of the Makeham parameter has been reported to improve the estimation of Gompertz parameters. Both models separate initial mortality rate (vulnerability) from an age-dependent increase in mortality (aging rate). We subjected the obtained Gompertz parameters to a meta-analysis. We find that DR reduced aging rate without affecting vulnerability. The latter contrasts with the conclusion of a recent analysis of a largely overlapping data set, and we show how the earlier finding is due to a statistical artifact. Our analysis indicates that the biology underlying the life-extending effect of DR in rodents likely involves attenuated accumulation of damage, which contrasts with the acute effect of DR on mortality reported for Drosophila. Moreover, our findings show that the often-reported correlation between aging rate and vulnerability does not constrain changing aging rate without affecting vulnerability simultaneously. © 2013 John Wiley & Sons Ltd and the Anatomical Society.

    10. A macroecological glance at the structure of late Miocene rodent assemblages from Southwest Europe

      Science.gov (United States)

      Cano, Ana Rosa Gómez; Cantalapiedra, Juan L.; Álvarez-Sierra, M. Ángeles; Fernández, Manuel Hernández

      2014-10-01

      Deep-time perspectives in macroecology are essential with regard to understanding the impact of climate forcing on faunal communities. Using late Miocene rodent faunas (12 to 5 Ma) from two different biogeographical provinces from southwestern Europe, we asked whether the waxing and waning of faunas with dissimilar ecological affinities tracked climate in different ways. The latest middle Miocene featured a fauna dominated by dormice with forest and mixed-habitat affinities. This group declined towards the Upper Miocene. Rodent taxa with the highest values of richness at the beginning of the Upper Miocene are generalists in the southern province and specialists of forested habitats in the northern province. Finally, we identified a third, increasingly significant group of rodents linked to open landscapes towards the end of the Miocene. These three broad ecological groups showed differential responses to a complex set of interconnected circumstances, including the biogeographic structure of the study area and climatic changes throughout time.

    11. Comparing strategies for controlling an African pest rodent: an empirically based theoretical study

      DEFF Research Database (Denmark)

      Stenseth, Nils Chr.; Leirs, Herwig; Mercelis, Saskia

      2001-01-01

      of rats. Control measures affecting survival as well as reproduction were considered.4. The model showed that control measures reducing survival will only have long-term effects on population size if they are also applied when rodent densities are low. Control measures applied only when rodent densities...... are high will not have persistent effects, even at high mortality rates.5. The model demonstrated that control measures reducing reproduction are likely to prevent Mastomys outbreaks, but will keep densities low over a long period only when the contraceptive effect is strong (> 75% reduction).6. Provided...... in particular cause major economic losses in Africa through damage to crops. Attempts to develop dynamic population models for this and other pest rodents are ongoing. 2. Demographic estimates from a capture-mark-recapture (CMR) study in Tanzania were used to parameterize a population model for this species...

    12. The in vivo rodent test systems for assessment of carcinogenic potential

      DEFF Research Database (Denmark)

      van der Laan, Jan-Willem; Spindler, Per

      2002-01-01

      A Drug Information Association (DIA) workshop was held in May 2001 to discuss the outcome of the International Life Sciences Institute-Health and Environmental Sciences Institute (ILSI-HESI) project on alternative models for carcinogenicity assessment such as the P53(+/-) and XPA(+/-) knockout...... mouse models, the RasH2 and Tg.AC transgenic mouse models, and the neonatal mouse model. The "ICH Guideline S1B on Testing for Carcinogenicity of Pharmaceuticals" advocates that carcinogenicity testing of pharmaceuticals, when needed, might be carried out choosing one 2-year rodent carcinogenicity study...... (rat) plus one other study that supplements the 2-year study and providing additional information that is not readily available from the 2-year study: either (1) a short- or medium-term in vivo rodent test system or (2) a 2-year carcinogenicity study in a second rodent species (mouse). Another topic...

    13. Differential responses of Miocene rodent metacommunities to global climatic changes were mediated by environmental context.

      Science.gov (United States)

      Blanco, Fernando; Gómez Cano, Ana Rosa; Cantalapiedra, Juan L; Domingo, M Soledad; Domingo, Laura; Menéndez, Iris; Flynn, Lawrence J; Hernández Fernández, Manuel

      2018-02-06

      The study of how long-term changes affect metacommunities is a relevant topic, that involves the evaluation of connections among biological assemblages across different spatio-temporal scales, in order to fully understand links between global changes and macroevolutionary patterns. We applied multivariate statistical analyses and diversity tests using a large data matrix of rodent fossil sites in order to analyse long-term faunal changes. Late Miocene rodent faunas from southwestern Europe were classified into metacommunities, presumably sharing ecological affinities, which followed temporal and environmental non-random assembly and disassembly patterns. Metacommunity dynamics of these faunas were driven by environmental changes associated with temperature variability, but there was also some influence from the aridity shifts described for this region during the late Miocene. Additionally, while variations in the structure of rodent assemblages were directly influenced by global climatic changes in the southern province, the northern sites showed a pattern of climatic influence mediated by diversity-dependent processes.

    14. Rhipicephalus sanguineus sensu lato(Ixodidae in synantropic rodents in Rio Grande do Sul, Brazil

      Directory of Open Access Journals (Sweden)

      Kathleen Tavares Winkel

      Full Text Available Rhipicephalus sanguineus, the brown dog tick, is responsible for maintaining and transmitting various pathogens, both in animals and human beings, and it is of great sanitary importance. This communication reports the first occurrence of Rhipicephalus sanguineus sensu lato parasitizing Rattus norvegicus in the state of Rio Grande do Sul, Brazil, and it is also the first record of this tick species parasitizing Rattus rattus in Brazil. The rodents were captured from the port area, located in the city of Pelotas, Rio Grande do Sul, Brazil. We collected 6 larvae of this tick species from 2 male R. rattus individuals, and 3 larvae from 2 female R. norvegicus individuals; parasitized specimens of both rodent species were captured from different sites within the experimental area. This record broadens the number of Rhipicephalus sanguineus sensu lato hosts in urban areas, indicating the need for continued monitoring on population density for both R. sanguineus and synanthropic rodents.

    15. Ecology, Genetic Diversity, and Phylogeographic Structure of Andes Virus in Humans and Rodents in Chile▿

      Science.gov (United States)

      Medina, Rafael A.; Torres-Perez, Fernando; Galeno, Hector; Navarrete, Maritza; Vial, Pablo A.; Palma, R. Eduardo; Ferres, Marcela; Cook, Joseph A.; Hjelle, Brian

      2009-01-01

      Andes virus (ANDV) is the predominant etiologic agent of hantavirus cardiopulmonary syndrome (HCPS) in southern South America. In Chile, serologically confirmed human hantavirus infections have occurred throughout a wide latitudinal distribution extending from the regions of Valparaíso (32 to 33°S) to Aysén (46°S) in southern Patagonia. In this study, we found seropositive rodents further north in the Coquimbo region (30°S) in Chile. Rodent seroprevalence was 1.4%, with Oligoryzomys longicaudatus displaying the highest seroprevalence (5.9%), followed by Abrothrix longipilis (1.9%) and other species exhibiting ≤0.6% seropositivity. We sequenced partial ANDV small (S) segment RNA from 6 HCPS patients and 32 rodents of four different species collected throughout the known range of hantavirus infection in Chile. Phylogenetic analyses showed two major ANDV South (ANDV Sout) clades, congruent with two major Chilean ecoregions, Mediterranean (Chilean matorral [shrubland]) and Valdivian temperate forest. Human and rodent samples grouped according to geographic location. Phylogenetic comparative analyses of portions of S and medium segments (encoding glycoproteins Gn and Gc) from a subset of rodent specimens exhibited similar topologies, corroborating two major ANDV Sout clades in Chile and suggesting that yet unknown factors influence viral gene flow and persistence throughout the two Chilean ecoregions. Genetic algorithms for recombination detection identified recombination events within the S segment. Molecular demographic analyses showed that the virus is undergoing purifying selection and demonstrated a recent exponential growth in the effective number of ANDV Sout infections in Chile that correlates with the increased number of human cases reported. Although we determined virus sequences from four rodent species, our results confirmed O. longicaudatus as the primary ANDV Sout reservoir in Chile. While evidence of geographic differentiation exists, a single

    16. The Prevalence of Trypanosoma cruzi, the Causal Agent of Chagas Disease, in Texas Rodent Populations.

      Science.gov (United States)

      Aleman, Adriana; Guerra, Trina; Maikis, Troy J; Milholland, Matthew T; Castro-Arellano, Ivan; Forstner, Michael R J; Hahn, Dittmar

      2017-03-01

      Rodent species were assessed as potential hosts of Trypanosoma cruzi, the etiologic agent of Chagas disease, from five sites throughout Texas in sylvan and disturbed habitats. A total of 592 rodents were captured, resulting in a wide taxonomic representation of 11 genera and 15 species. Heart samples of 543 individuals were successfully analyzed by SybrGreen-based quantitative PCR (qPCR) targeting a 166 bp fragment of satellite DNA of T. cruzi. Eight rodents representing six species from six genera and two families were infected with T. cruzi. This is the first report of T. cruzi in the pygmy mouse (Baiomys taylori) and the white-footed mouse (Peromyscus leucopus) for the USA. All infected rodents were from the southernmost site (Las Palomas Wildlife Management Area). No differences in pathogen prevalence existed between disturbed habitats (5 of 131 tested; 3.8%) and sylvan habitats (3 of 40 tested; 7.5%). Most positives (n = 6, 16% prevalence) were detected in late winter with single positives in both spring (3% prevalence) and fall (1% prevalence). Additionally, 30 Triatoma insects were collected opportunistically from sites in central Texas. Fifty percent of these insects, i.e., 13 T. gerstaeckeri (68%), and two T. lecticularia (100%) were positive for T. cruzi. Comparative sequence analyses of 18S rRNA of samples provided identical results with respect to detection of the presence or absence of T. cruzi and assigned T. cruzi from rodents collected in late winter to lineage TcI. T. cruzi from Triatoma sp. and rodents from subsequent collections in spring and fall were different, however, and could not be assigned to other lineages with certainty.

    17. Prevalence of Leishmania species in rodents: A systematic review and meta-analysis in Iran.

      Science.gov (United States)

      Foroutan, Masoud; Khademvatan, Shahram; Majidiani, Hamidreza; Khalkhali, Hamidreza; Hedayati-Rad, Faezeh; Khashaveh, Shahla; Mohammadzadeh, Habib

      2017-08-01

      Leishmaniasis are diverse group of diseases caused by numerous species of genus Leishmania. Herein we have contrived a systematic review and meta-analysis on the prevalence of Leishmania species in rodents of Iran. For this purpose, following the general methodology recommended for systematic reviews and meta-analysis, six English databases (PubMed, Science Direct, Scopus, Ovid, Web of Science and Google Scholar) and four Persian databases (Magiran, SID, Iran Doc and Iran Medex) were explored during January 1995 till June 2015. Papers were selected based on 8 pre-defined inclusion criteria. During the years, a total number of 4485 different rodents were captured; among which 1291 cases were Leishmania positive. The calculated weighted prevalence of Leishmania species in rodents was 23% (95% CI=18-28). Given geographical zones of Iran, the highest and lowest prevalence rate was belonged to North 50% (95% CI=40-61) and West 11% (95% CI=5-17), respectively. Rhombomys opimus (1766), Meriones lybicus (1258) and Tatera indica (488) were the three most abundant captured rodents, while the highest prevalence of Leishmania species was observed in Nesokia indica 48% (95% CI=42-54) and followed by R. opimus 39% (95% CI=30-47). Egger's regression test was performed to detect publication bias, which revealed it may not have a significant influence on overall weighted prevalence estimate (P=0.317). Meta-regression analysis demonstrated that there is no significant relationship between overall prevalence with sample size (P=0.1) and year of publication (P=0.7). The results showed remarkable prevalence of Leishmania species in rodent reservoirs. In future, adopting a suitable strategy for control and combat with rodents is necessary. Copyright © 2017 Elsevier B.V. All rights reserved.

    18. Lawsonia intracellularis in the feces of wild rodents and stray cats captured around equine farms.

      Science.gov (United States)

      Hwang, Jeong-Min; Seo, Myung-Ji; Yeh, Jung-Yong

      2017-08-11

      Proliferative enteropathy is a global enteric disease of particular importance in pigs. The causative bacterium, Lawsonia intracellularis, has a wide range of susceptible host species. Recently, L. intracellularis has been recognized as an etiologic agent of an emerging enteric disease in foals called equine proliferative enteropathy (EPE). The presence of L. intracellularis in nonruminant wildlife has raised questions regarding the role of these species in EPE transmission. This study investigated exposure to L. intracellularis in wild rodents and feral cats from eight farms with confirmed EPE. Serum (42) and fecal (40) samples from resident foals and fecal samples (131), intestinal mucosa tissues (14), and mesenteric lymph nodes (14) from wild and feral animals were collected for the evaluation of the farm status and the molecular detection of L. intracellularis following the diagnosis of EPE in index cases. Fresh feces from wild rodents and feral cats were collected from the ground while walking the premises or after trapping the animals using live traps. A total of 3 brown rats, 7 house mice, 1 striped field mouse, 2 grey red-backed voles, and 3 feral cats showed evidence of prior exposure to L. intracellularis. Our data add to increasing evidence demonstrating the potential for L. intracellularis transmission and infection in wild rodents and feral cats and provide possible evidence of interspecies transmission. The exposure of wild rodents and feral cats provides potential evidence for the spillover of L. intracellularis to wildlife species and raises the question of spillback to horses. Additionally, these animals may represent an indicator of environmental exposure or may be actively involved in the transmission of L. intracellularis to foals by acting as potential reservoir/amplifier hosts. This study is the first to demonstrate the magnitude of L. intracellularis shedding in the feces of wild rodents and feral cats and to indicate the significant

    19. Food habits of rodents inhabiting arid and semi-arid ecosystems of central New Mexico

      Science.gov (United States)

      Hope, Andrew G.; Parmenter, Robert R.

      2007-01-01

      In this study, we describe seasonal dietary composition for 15 species of rodents collected in all major habitats on the Sevilleta National Wildlife Refuge (Socorro County) in central New Mexico. A comprehensive literature review of food habits for these species from throughout their distribution also is provided. We collected rodents in the field during winter, spring and late summer in 1998 from six communities: riparian cottonwood forest; piñon-juniper woodland; juniper-oak savanna; mesquite savanna; short-grass steppe; and Chihuahuan Desert scrubland. Rodents included Spermophilus spilosoma (Spotted Ground Squirrel), Perognathus flavescens (Plains Pocket Mouse), Perognathus flavus (Silky Pocket Mouse), Dipodomys merriami (Merriam’s Kangaroo Rat), Dipodomys ordii (Ord’s Kangaroo Rat), Dipodomys spectabilis (Banner-tailed Kangaroo Rat), Reithrodontomys megalotis (Western Harvest Mouse), Peromyscus boylii (Brush Mouse), Peromyscus eremicus (Cactus Mouse), Peromyscus leucopus (White-footed Mouse), Peromyscus truei (Piñon Mouse), Onychomys arenicola (Mearn’s Grasshopper Mouse), Onychomys leucogaster (Northern Grasshopper Mouse), Neotoma albigula/leucodon (White-throated Woodrats), and Neotoma micropus (Southern Plains Woodrat). We collected stomach contents of all species, and cheek-pouch contents of heteromyids, and quantified them in the laboratory. We determined seasonal diets in each habitat by calculating mean percentage volumes of seeds, arthropods and green vegetation (plant leaves and stems) for each species of rodent. Seeds consumed by each rodent were identified to genus, and often species, and quantified by frequency counts. Comparisons of diets between and among species of rodents, seasons, and ecosystems were also examined. We provide an appendix of all plant taxa documented.

    20. Phylogeographic Characterization of Tick-Borne Encephalitis Virus from Patients, Rodents and Ticks in Slovenia

      Science.gov (United States)

      Fajs, Luka; Durmiši, Emina; Knap, Nataša; Strle, Franc; Avšič-Županc, Tatjana

      2012-01-01

      Tick-borne encephalitis virus (TBEV) is the most important arboviral agent causing infections of the central nervous system in central Europe. Previous studies have shown that TBEV exhibits pronounced genetic variability, which is often correlated to the geographical origin of TBEV. Genetic variability of TBEV has previously been studied predominantly in rodents and ticks, while information about the variability in patients is scarce. In order to understand the molecular relationships of TBEV between natural hosts, vectors and humans, as well as correlation between phylogenetic and geographical clustering, sequences of TBEV E and NS5 protein genes, were obtained by direct sequencing of RT-PCR products from TBE-confirmed patients as well as from rodents and ticks collected from TBE-endemic regions in Slovenia. A total of 27 partial E protein gene sequences representing 15 human, 4 rodent and 8 tick samples and 30 partial NS5 protein gene sequences representing 17 human, 5 rodent and 8 tick samples were obtained. The complete genome sequence of TBEV strain Ljubljana I was simultaneously obtained. Phylogenetic analysis of the E and NS5 protein gene sequences revealed a high degree of TBEV variability in patients, ticks and rodents. Furthermore, an evident correlation between geographical and phylogenetic clustering was shown that was independent of the TBEV host. Moreover, we show the presence of a possible recombination event in the TBEV genome obtained from a patient sample, which was supported with multiple recombination event detection methods. This is the first study that simultaneously analyzed the genetic relationships of directly sequenced TBEV samples from patients, ticks and rodents and provides the largest set of patient-derived TBEV sequences up to date. In addition, we have confirmed the geographical clustering of TBEV sequences in Slovenia and have provided evidence of a possible recombination event in the TBEV genome, obtained from a patient. PMID

    1. A model of Leptospirosis infection in an African rodent to determine risk to humans: Seasonal fluctuations and the impact of rodent control

      DEFF Research Database (Denmark)

      Holt, J; Davis, S; Leirs, Herwig

      2006-01-01

      Human leptospirosis (Leptospira spp. infection) is aworldwide public health problem that is of greatest concern for humid tropical and subtropical regions. The magnitude of the problem in these areas is larger because of the climatic and environmental conditions the bacterium face outside...... their hosts but also because of the frequency of contacts between people and sources of infection. Rodents are thought to play the most important role in the transmission of human leptospirosis. We here model the dynamics of infection in an African rodent (Mastomys natalensis) that is thought...... to be the principal source of infection in parts of Tanzania. Our model, representing the climatic conditions in central Tanzania, suggests a strong seasonality in the force of infection on humans with a peak in the abundance of infectious mice between January and April in agricultural environments. In urban areas...

    2. Pulmonary Toxicity Studies of Lunar Dust in Rodents

      Science.gov (United States)

      Lam, Chiu-Wing; James, John T.

      2012-01-01

      NASA has been contemplating returning astronauts to the moon for long-duration habitation and research and using it as a stepping-stone to Mars. Other spacefaring nations are planning to send humans to the moon for the first time. The surface of the moon is covered by a layer of fine dust. Fine terrestrial dusts, if inhaled, are known to pose a health risk to humans. Some Apollo crews briefly exposed to moon dust that adhered to spacesuits and became airborne in the Lunar Module reported eye and throat irritation. The habitable area of any lunar landing vehicle or outpost would inevitably become contaminated with lunar dust. To assess the health risks of exposure of humans to airborne lunar dust, we evaluated the toxicity of Apollo 14 moon dust in animal lungs. Studies of the pulmonary toxicity of a dust are generally first done by intratracheal instillation (ITI) of aqueous suspensions of the test dust into the lungs of rodents. If a test dust is irritating or cytotoxic to the lungs, the alveolar macrophages, after phagocytizing the dust particles, will release cellular messengers to recruit white blood cells (WBCs) and to induce dilation of blood capillary walls to make them porous, allowing the WBCs to gain access to the alveolar space. The dilation of capillary walls also allows serum proteins and water entering the lung. Besides altering capillary integrity, a toxic dust can also directly kill the cells that come into contact with it or ingest it, after which the dead cells would release their contents, including lactate dehydrogenase (a common enzyme marker of cell death or tissue damage). In the treated animals, we lavaged the lungs 1 and 4 weeks after the dust instillation and measured the concentrations of these biomarkers of toxicity in the bronchioalveolar lavage fluids to determine the toxicity of the dust. To assess whether the inflammation and cellular injury observed in the biomarker study would lead to persistent or progressive histopathological

    3. A new form of rodent placentation in the relict species, Laonastes aenigmamus (Rodentia Diatomyidae)

      DEFF Research Database (Denmark)

      Carter, Anthony Michael; Enders, A C; Jones, C J P

      2013-01-01

      INTRODUCTION: The Laotian rock rat is a relict species in a sister group relationship to hystricognath rodents (Hystricognathi). We asked whether there were similarities in placentation that might reflect this relationship or differences that might cast light on the evolution of Hystricognathi....... METHODS: We examined the reproductive tract of nonpregnant (n = 5), early (n = 3) and mid to late gestation (n = 2) females. Selected characters were mapped to a phylogenetic tree to examine their evolution in rodents. RESULTS: The chorionic placenta was discoid and labyrinthine with a spongy zone...

    4. [Identification of wild rodents as hosts of Angiostrongylus costaricencis in southern Brazil].

      Science.gov (United States)

      Graeff-Teixeira, C; de Avila-Pires, F D; Machado, R de C; Camillo-Coura, L; Lenzi, H L

      1990-01-01

      Increasing number of human cases of abdominal angiostrongyliasis has been diagnosed in the south of Brazil. The main definitive host of Angiostrongylus costaricensis in Central America is the cotton rat (Sigmodon hispidus) that does not occur in South America, except in the north of Colombia, Peru and Venezuela. Rodents were captured in the endemic area in Rio Grande do Sul (RS) and definitive hosts were identified for the first time in Brazil: Oryzomys nigripes and Oryzomys ratticeps. O. nigripes is a small wild rodent and it appears to be the main definitive host of A. costaricensis in the highlands of RS, Brazil's southernmost State.

    5. Measuring Motivation and Reward-Related Decision Making in the Rodent Operant Touchscreen System.

      Science.gov (United States)

      Heath, Christopher J; Phillips, Benjamin U; Bussey, Timothy J; Saksida, Lisa M

      2016-01-04

      This unit is designed to facilitate implementation of the fixed and progressive ratio paradigms and the effort-related choice task in the rodent touchscreen apparatus to permit direct measurement of motivation and reward-related decision making in this equipment. These protocols have been optimized for use in the mouse and reliably yield stable performance levels that can be enhanced or suppressed by systemic pharmacological manipulation. Instructions are also provided for the adjustment of task parameters to permit use in mouse models of neurodegenerative disease. These tasks expand the utility of the rodent touchscreen apparatus beyond the currently available battery of cognitive assessment paradigms. Copyright © 2016 John Wiley & Sons, Inc.

    6. Sensing through friction: the biomechanics of texture perception in rodents and primates

      Science.gov (United States)

      Debrégeas, Georges; Boubenec, Yves

      2015-10-01

      Rodents and primates possess an exquisite tactile sensitivity, which allows them to extract a wealth of information about their immediate environment. They can distinguish subtle differences in surface roughness through tactile exploration in a much more precise way than they can do visually. In both sensory systems, tactile information is contained in the sequence of deformation of the tactile organ--the facial hair for rodents (the whiskers), the digital skin for primates -- elicited by active rubbing on the probed surface (Figure 8.1). These deformations, registered by mechanosensitive neurons located in inner tissues, are processed by the central nervous system to produce a sensory representation of the surface...

    7. Monitoring rodents movements with a biomarker around introduction and feeding foci in an urban environment in Tanzania

      DEFF Research Database (Denmark)

      Mohr, Katrine; Leirs, Herwig; Katakweba, Abdul

      2007-01-01

      , Rhodamine B (RB), we investigated the distances over which rodents are active around such potential introduction sites. Animals feeding at such sites were traced up to 100 m distant within a period of 10 days.We found that RB is a practical alternative for studying rodent movements. These results may be...

    8. [Population change of farmland rodent and the influences of climate and cultivation factors in Fengxian District of Shanghai, China].

      Science.gov (United States)

      Fei, Lei; Wang, Zu-guo; Yao, Yao; Xu, Xiang-ming; Gu, Pin-qiang

      2015-02-01

      We analyzed the changes of rodent population from 1988 to 2013 in Fengxian District, Shanghai, and discussed the relevance of rodent population dynamics and climate, and ecological factors. Results showed that the average rat density was 1.3% from 1988 to 2013, and the dominant species was Apodemus agrarius. There was little change of density between years. The average composition ratio was 97.5%. The peak of rodent density appeared from February to May, highest in March. Average density and peak decreased obviously year after year. Numbers of adult rodents of 1st group were positively correlated, while that of adult rodents of 2nd group and elderly group negatively correlated with years. Rat age presented a shortened trend annually. Rodent density and temperature factors were negatively correlated except in January. Extreme warmth in February had a lagged, positive effect on the rat density. Precipitation factors had no significant correlation with the density of rodents. Relative humidity was positively correlated with the density, mostly. Planting structure adjustment and reduction of planting acreage were significantly correlated with the reduction of rodent density. Increased deratization rate was also correlated with the reduction.

    9. Occurrence of Toxoplasma gondii antibodies in wild rodents and marsupials from the Atlantic forest, State of Sao Paulo, Brazil

      Science.gov (United States)

      Toxoplasma gondii is a protozoan parasite that infects a large spectrum of warm-blooded animals, including humans. Small mammals and rodents play an important role in the epidemiology of T. gondii because they are sources of infection for domestic and feral cats. Serum samples from 151 rodents and 4...

    10. The meaning of peer culture for learning at school: the example of a student company / O significado da cultura de pares para a aprendizagem na escola: o exemplo de uma empresa júnior

      Directory of Open Access Journals (Sweden)

      Barbara Asbrand

      2011-06-01

      diferentes contextos educacionais, tais como momentos em sala de aula de diferentes disciplinas, atividades escolares extra-curriculares e trabalho juvenil não-formal fora da escola. O principal objetivo do texto é um estudo de caso de um grupo de estudantes do sexo feminino que coordenam lojas mundiais na forma de Empresa Júnior. O objetivo é descrever uma cultura de aprendizagem específica num Gymnasyum, uma escola de gramática alemã, bem como o processo de aprendizagem que ocorre dentro de um certo arranjo didático-pedagógico. Neste contexto, a empresa júnior é importante tanto como projeto extra escolar, quanto como meio de integração dos assuntos e trabalhos nas diferentes lições ou aulas das diversas disciplinas. A integração da educação global na cultua escolar resulta da presença da empresa júnior no dia a dia da escola e a combinação de processos informais de aprendizagem dentro do grupo de pares e sistemática introdução de lições escolares. A pesquisa revela o grande potencial para a desejada aquisição de competências e conhecimento. Isto por sua vez demonstra a extensão na qual o aprendizado estudantil é encorajado por uma escola e cultura de aprendizagem em particular.

    11. Determinación de compuestos hidrocarbonados en la pared celular de P. maximum y L. leucocephala en silvopastoreo Determination of hydrocarbonated compounds in the cell wall from P. maximum and L. leucocephala under silvopastoral system conditions

      Directory of Open Access Journals (Sweden)

      Tania Sánchez

      2009-09-01

      Full Text Available Con el objetivo de determinar la concentración de n-alcanos y alcoholes de cadena larga en la pared celular de Panicum maximum cv. Likoni y Leucaena leucocephala cv. Cunningham, se realizó un estudio en una asociación de gramíneas mejoradas y leucaena de 10 años de establecida, la cual ocupa un área de 1,6 ha. Se seleccionaron dichas especies por ser las más representativas en la composición florística. Las muestras se colectaron de enero a diciembre del 2005 y se secaron. La concentración de n-alcanos de cadena impar fue de 167,97 y 222,96 mg/kg de MS y 134,11 y 137,27 mg/kg de MS para guinea y leucaena, en el período poco lluvioso y en el lluvioso, respectivamente. A su vez la concentración de alcoholes de cadena par para la leucaena presentó un valor mayor(2 754,60 y 3 830,18 mg/kg de MS para el período poco lluvioso y lluvioso, respectivamente, que en la guinea (2 571,73-3 679,65 mg/kg de MS para cada período, respectivamente. Se concluye que la concentración de n-alcanos de cadena larga impar fue baja para P. maximum y L. leucocephala en ambos períodos del año; sin embargo, presentaron concentraciones elevadas de alcoholes de cadena larga par, que pudieran ser utilizados como marcadores naturales en las dos especies.With the objective of determining the concentration of n-alkanes and long-chain alcohols in the cell wall of Panicum maximum cv. Likoni and Leucaena leucocephala cv. Cunningham, a study was conducted in an association of improved grasses and leucaena ten years after being established, which occupies an area of 1,6 ha. Such species were selected for being the most representative ones in the floristic composition. The samples were collected from January to December, 2005 and were dried. The concentration of odd-chain n-alkanes was 167,97 and 222,96 mg/kg DM and 134,11 and 137,27 mg/kg DM for Guinea grass and leucaena in the dry and rainy season, respectively. In turn, the concentration of even-chain alcohols for

    12. A study of ectoparasites in wild rodents of the Jaz Murian area in the southeast of Iran

      Directory of Open Access Journals (Sweden)

      Asghar Khajeh

      2017-07-01

      Full Text Available Objective: To detect wild rodents ectoparasites in the southeast of Iran. Methods: In this survey, the wild rodents were trapped from 2014 to 2015. The captured rodents were checked for any ectoparasites. Results: In this study, 681 ectoparasites belonged to 6 species of flea, 2 species of lice, 1 species of mite and 2 species of hard tick were collected. The flea species were including, Xenopsylla gerbilli, Xenopsylla cheopis, Xenopsylla buxtoni, Xenopsylla conformis, Nosopsyllus medus and Amphipysylla spp., the lice species were including Hoplopleura spp. and Polyplax spp., the mite species was Ornithonyssus bacoti and tick species were Rhipicephalus spp. and Hyalomma spp. Conclusions: Among all ectoparasites, Hoplopleura spp. and Amphipysylla spp. had the high and low frequency infestation in rodents, respectively. Also among captured rodents, the highest ectoparasites infestation was found in Tatera indica and no ectoparasites in Apodemus witherbyi, Cricetelus migratorius, and Microtus mystacinus kermanesis.

    13. Lack of a response of the sub-tropical rodent (Saccostomus ...

      African Journals Online (AJOL)

      1998-03-09

      Mar 9, 1998 ... A potential strategy for southern African small mammals to maximise reproductive success is to cue breeding activity to rainfall and subsequent vegetative growth via a secondary plant compound such as 6-methoxyben- zoxazolinone (6MBOA). This study investigated whether the sub-tropical rodent ...

    14. an ecological study on rodents of natural vegetation and farm lands ...

      African Journals Online (AJOL)

      preferred customer

      Population density of rodents was high in the bush land and forest habitats. Plant matters were the most ... The area is characterized by a mild sub-tropical temperature range of ..... habitat in structuring small mammal commu- nities in a tropical ...

    15. A new species of the Rodent Baiomys from Aruba and Curaçao

      NARCIS (Netherlands)

      Husson, A.M.

      1960-01-01

      In his paper on the mammals of the islands of Aruba, Curaçao, and Bonaire (situated off the north coast of Venezuela), WAGENAAR HUMMELINCK (1940 a, p. 69) mentioned a juvenile specimen of a cricetine rodent which was identified by Mr. M. A. C. HINTON and Mr. R. W. HAYMAN as probably belonging to the

    16. Variation in apical hook length reflects the intensity of sperm competition in murine rodents

      Czech Academy of Sciences Publication Activity Database

      Šandera, M.; Albrecht, Tomáš; Stopka, P.

      2013-01-01

      Roč. 8, č. 7 (2013), e68427 E-ISSN 1932-6203 Institutional support: RVO:68081766 Keywords : postcopulatory sexual selection * field mice Apodemus * female promiscuity * acrosome reaction * Passerine birds * Muroid rodents * genus Apodemus * cytochrome-b * testes size * house mice Subject RIV: EG - Zoology Impact factor: 3.534, year: 2013

    17. Contribution of land use to rodent flea load distribution in the plague ...

      African Journals Online (AJOL)

      These findings suggest that land use factors have a major influence on rodent flea abundance which can be taken as a proxy for plague infection risk. The results further point to the need for a comprehensive package that includes land tillage and crop type considerations on one hand and the associated human activities on ...

    18. Unpredictability of escape trajectory explains predator evasion ability and microhabitat preference of desert rodents.

      Science.gov (United States)

      Moore, Talia Y; Cooper, Kimberly L; Biewener, Andrew A; Vasudevan, Ramanarayan

      2017-09-05

      Mechanistically linking movement behaviors and ecology is key to understanding the adaptive evolution of locomotion. Predator evasion, a behavior that enhances fitness, may depend upon short bursts or complex patterns of locomotion. However, such movements are poorly characterized by existing biomechanical metrics. We present methods based on the entropy measure of randomness from Information Theory to quantitatively characterize the unpredictability of non-steady-state locomotion. We then apply the method by examining sympatric rodent species whose escape trajectories differ in dimensionality. Unlike the speed-regulated gait use of cursorial animals to enhance locomotor economy, bipedal jerboa (family Dipodidae) gait transitions likely enhance maneuverability. In field-based observations, jerboa trajectories are significantly less predictable than those of quadrupedal rodents, likely increasing predator evasion ability. Consistent with this hypothesis, jerboas exhibit lower anxiety in open fields than quadrupedal rodents, a behavior that varies inversely with predator evasion ability. Our unpredictability metric expands the scope of quantitative biomechanical studies to include non-steady-state locomotion in a variety of evolutionary and ecologically significant contexts.Biomechanical understanding of animal gait and maneuverability has primarily been limited to species with more predictable, steady-state movement patterns. Here, the authors develop a method to quantify movement predictability, and apply the method to study escape-related movement in several species of desert rodents.

    19. The rodent research animal holding facility as a barrier to environmental contamination

      Science.gov (United States)

      Savage, P. D., Jr.; Jahns, G. C.; Dalton, B. P.; Hogan, R. P.; Wray, A. E.

      1989-01-01

      The rodent Research Animal Holding Facility (RAHF), developed by NASA Ames Research Center (ARC) to separately house rodents in a Spacelab, was verified as a barrier to environmental contaminants during a 12-day biocompatibility test. Environmental contaminants considered were solid particulates, microorganisms, ammonia, and typical animal odors. The 12-day test conducted in August 1988 was designed to verify that the rodent RAHF system would adequately support and maintain animal specimens during normal system operations. Additional objectives of this test were to demonstrate that: (1) the system would capture typical particulate debris produced by the animal; (2) microorganisms would be contained; and (3) the passage of animal odors was adequately controlled. In addition, the amount of carbon dioxide exhausted by the RAHF system was to be quantified. Of primary importance during the test was the demonstration that the RAHF would contain particles greater than 150 micrometers. This was verified after analyzing collection plates placed under exhaust air ducts and rodent cages during cage maintenance operations, e.g., waste tray and feeder changeouts. Microbiological testing identified no additional organisms in the test environment that could be traced to the RAHF. Odor containment was demonstrated to be less than barely detectable. Ammonia could not be detected in the exhaust air from the RAHF system. Carbon dioxide levels were verified to be less than 0.35 percent.

    20. Rodents are a risk factor for the spreading of pathogens on farms

      NARCIS (Netherlands)

      Meerburg, B.G.

      2010-01-01

      In a recent paper Messens et al. (2009) investigate the genetic diversity of thermotolerant Campylobacter in commercial broiler flocks and in the environment of broiler farms in Belgium. One of their conclusions is that although rodents can serve as vectors and reservoirs of Campylobacter (Meerburg

    1. Serologic evidence for Borrelia hermsii infection in rodents on federally owned recreational areas in California.

      Science.gov (United States)

      Fritz, Curtis L; Payne, Jessica R; Schwan, Tom G

      2013-06-01

      Tick-borne relapsing fever (TBRF) is endemic in mountainous regions of the western United States. In California, the principal agent is the spirochete Borrelia hermsii, which is transmitted by the argasid tick Ornithodoros hermsi. Humans are at risk of TBRF when infected ticks leave an abandoned rodent nest in quest of a blood meal. Rodents are the primary vertebrate hosts for B. hermsii. Sciurid rodents were collected from 23 sites in California between August, 2006, and September, 2008, and tested for serum antibodies to B. hermsii by immunoblot using a whole-cell sonicate and a specific antigen, glycerophosphodiester phosphodiesterase (GlpQ). Antibodies were detected in 20% of rodents; seroprevalence was highest (36%) in chipmunks (Tamias spp). Seroprevalence in chipmunks was highest in the Sierra Nevada (41%) and Mono (43%) ecoregions and between 1900 and 2300 meters elevation (43%). The serological studies described here are effective in implicating the primary vertebrate hosts involved in the maintenance of the ticks and spirochetes in regions endemic for TBRF.

    2. The need to implement the landscape of fear within rodent pest management strategies

      NARCIS (Netherlands)

      Krijger, Inge M.; Belmain, Steven R.; Singleton, Grant R.; Groot Koerkamp, Peter W.G.; Meerburg, Bastiaan G.

      2017-01-01

      Current reactive pest management methods have serious drawbacks such as the heavy reliance on chemicals, emerging genetic rodenticide resistance and high secondary exposure risks. Rodent control needs to be based on pest species ecology and ethology to facilitate the development of ecologically

    3. Rare Variant Analysis of Human and Rodent Obesity Genes in Individuals with Severe Childhood Obesity

      NARCIS (Netherlands)

      Hendricks, Audrey E.; Bochukova, Elena G.; Marenne, Gaëlle; Keogh, Julia M.; Atanassova, Neli; Bounds, Rebecca; Wheeler, Eleanor; Mistry, Vanisha; Henning, Elana; Körner, Antje; Muddyman, Dawn; McCarthy, Shane; Hinney, Anke; Hebebrand, Johannes; Scott, Robert A.; Langenberg, Claudia; Wareham, Nick J.; Surendran, Praveen; Howson, Joanna M M; Butterworth, Adam S.; Danesh, John; Nordestgaard, Børge G.; Nielsen, Sune F.; Afzal, Shoaib; Papadia, Sofia; Ashford, Sofie; Garg, Sumedha; Millhauser, Glenn L.; Palomino, Rafael I.; Kwasniewska, Alexandra; Tachmazidou, Ioanna; O'Rahilly, Stephen; Zeggini, Eleftheria; Barroso, Inês; Farooqi, I. Sadaf; Benzeval, Michaela; Burton, Jonathan; Buck, Nicholas; Jäckle, Annette; Kumari, Meena; Laurie, Heather; Lynn, Peter; Pudney, Stephen; Rabe, Birgitta; Wolke, Dieter; Overvad, Kim; Tjønneland, Anne; Clavel-Chapelon, Francoise; Kaaks, Rudolf; Boeing, Heiner; Trichopoulou, Antonia; Ferrari, Pietro; Palli, Domenico; Krogha, Vittorio; Panico, Salvatore; Tuminoa, Rosario; Matullo, Giuseppe; Boer, Jolanda Ma; Van Der Schouw, Yvonne; Weiderpass, Elisabete; Quiros, J. Ramon; Sánchez, María José; Navarro, Carmen; Moreno-Iribas, Conchi; Arriola, Larraitz; Melander, Olle; Wennberg, Patrik; Key, Timothy J.; Riboli, Elio; Al-Turki, Saeed; Anderson, Carl A; Anney, Richard; Antony, Dinu; Soler Artigas, María; Ayub, Muhammad; Bala, Senduran; Barrett, Jeffrey C; Beales, Phil; Bentham, Jamie; Bhattacharyaa, Shoumo; Birney, Ewan; Blackwooda, Douglas; Bobrow, Martin; Bolton, Patrick F.; Boustred, Chris; Breen, Gerome; Calissanoa, Mattia; Carss, Keren; Charlton, Ruth; Chatterjee, Krishna; Chen, Lu; Ciampia, Antonio; Cirak, Sebahattin; Clapham, Peter; Clement, Gail; Coates, Guy; Coccaa, Massimiliano; Collier, David A; Cosgrove, Catherine; Coxa, Tony; Craddock, Nick; Crooks, Lucy; Curran, Sarah; Curtis, David; Daly, Allan; Danecek, Petr; Day, Ian N M; Day-Williams, Aaron G; Dominiczak, Anna; Down, Thomas; Du, Yuanping; Dunham, Ian; Durbin, Richard; Edkins, Sarah; Ekong, Rosemary; Ellis, Peter; Evansa, David M.; FitzPatrick, David R.; Flicek, Paul; Floyd, James S.; Foley, A. Reghan; Franklin, Christopher S.; Futema, Marta; Gallagher, Louise; Gaunt, Tom R.; Geihs, Matthias; Geschwind, Daniel H.; Greenwood, Celia M.T.; Griffin, Heather; Grozeva, Detelina; Guo, Xiaosen; Guo, Xueqin; Gurling, Hugh; Hart, Deborah J.; Holmans, Peter A; Howie, Bryan; Huang, Jie; Huang, Liren; Hubbard, Tim; Humphries, Steve E.; Hurles, Matthew E.; Hysi, Pirro G.; Iotchkova, Valentina; Jackson, David K.; Jamshidi, Yalda; Joyce, Chris; Karczewski, Konrad J.; Kaye, Jane; Keane, Thomas; Kemp, John P.; Kennedy, Karen; Kent, Alastair; Khawaja, Farrah; Van Kogelenberg, Margriet; Kolb-Kokocinski, Anja; Lachance, Genevieve; Langford, Cordelia; Lawson, Daniel; Lee, Irene; Lek, Monkol; Li, Rui; Li, Yingrui; Liang, Jieqin; Lin, Hong; Liu, Ryan; Lönnqvist, Jouko; Lopes, Luis R.; Lopes, Margarida; MacArthur, Daniel G.; Mangino, Massimo; Marchini, Jonathan; Maslen, John; Mathieson, Iain; McGuffin, Peter; McIntosh, Andrew M.; McKechanie, Andrew G.; McQuillin, Andrew; Memari, Yasin; Metrustry, Sarah; Migone, Nicola; Min, Josine L.; Mitchison, Hannah M; Moayyeri, Alireza; Morris, Andrew D.; Morris, James; Muntoni, Francesco; Northstone, Kate; O'Donovan, Michael C.; Onoufriadis, Alexandros; Oualkacha, Karim; Owen, Michael J; Palotie, Aarno; Panoutsopoulou, Kalliope; Parker, Victoria; Parr, Jeremy R.; Paternoster, Lavinia; Paunio, Tiina; Payne, Felicity; Payne, Stewart J.; Perry, John R. B.; Pietilainen, Olli; Plagnol, Vincent; Pollitt, Rebecca C.; Porteous, David J.; Povey, Sue; Quail, Michael A.; Quaye, Lydia; Raymond, F. Lucy; Rehnström, Karola; Richards, J Brent; Ridout, Cheryl K.; Ring, Susan M.; Ritchie, Graham R.S.; Roberts, Nicola; Robinson, Rachel L.; Savage, David B.; Scambler, Peter; Schiffels, Stephan; Schmidts, Miriam; Schoenmakers, Nadia; Scott, Richard H.; Semple, Robert K.; Serra, Eva; Sharp, Sally I.; Shaw, Adam; Shihab, Hashem A.; Shin, So Youn; Skuse, David; Small, Kerrin S; Smee, Carol; Smith, Blair H.; Davey Smith, George; Soranzo, Nicole; Southam, Lorraine; Spasic-Boskovic, Olivera; Spector, Timothy D; St Clair, David; St Pourcain, Beate; Stalker, Jim; Stevens, Elizabeth; Sun, Jianping; Surdulescu, Gabriela L; Suvisaari, Jaana; Syrris, Petros; Taylor, Rohan; Tian, Jing; Timpson, Nicholas J.; Tobin, Martin D; Valdes, Ana M.; Vandersteen, Anthony M.; Vijayarangakannan, Parthiban; Visscher, Peter M.; Wain, Louise V.; Walter, Klaudia; Walters, James T.R.; Wang, Guangbiao; Wang, Jun; Wang, Nai-Yu; Ward, Kirsten; Whyte, Tamieka; Williams, Hywel J.; Williamson, Kathleen A.; Wilson, Crispian; Wilson, Scott G.; Wong, Kim; Xu, Changjiang; Yang, Jian; Zhang, Feng; Zhang, Pingbo; Zheng, Hou Feng

      2017-01-01

      Obesity is a genetically heterogeneous disorder. Using targeted and whole-exome sequencing, we studied 32 human and 87 rodent obesity genes in 2,548 severely obese children and 1,117 controls. We identified 52 variants contributing to obesity in 2% of cases including multiple novel variants in GNAS,

    4. Transcutaneous measurement of glomerular filtration rate in small rodents: through the skin for the win?

      Science.gov (United States)

      Ellery, Stacey J; Cai, Xiaochu; Walker, David D; Dickinson, Hayley; Kett, Michelle M

      2015-03-01

      Rodent models of renal physiology and pathology are crucial to our understanding of the molecular, histological and functional sequelae that contribute to kidney diseases. One of the most important measures of renal function is glomerular filtration rate (GFR). While the accurate determination of GFR is pivotal to understanding the progression of disease and/or the benefits of treatment strategies, in rodents the conventional methods for assessment of GFR are inconvenient and cumbersome, not the least because they involve stress and often anaesthesia. The legitimacy of assay-based assessment of plasma and urine markers of GFR in mice has also been heavily scrutinized for their insensitivity to minor declines in GFR and inaccurate detection of renal biomarkers. While infusion-based clearance methods of GFR assessment are thus the gold standard in terms of accuracy, they are limited by the fact that they are primarily non-recovery procedures. This presents a dilemma when trying to document the progression of renal disease, as these measures cannot be taken in the same experimental subject. Here we review a technique of transcutaneous measurement of fluorescein isothiocyanate-labelled sinistrin to calculate GFR in small rodents, using a non-invasive clearance device (NIC-Kidney Device). This is a recently validated non-invasive technique for measuring GFR in small rodents that allows for the real-time measurement of GFR in conscious animals, without the need for plasma and urine assays. © 2014 Asian Pacific Society of Nephrology.

    5. Effects of glyphosate exposure on sperm concentration in rodents: A systematic review and meta-analysis.

      Science.gov (United States)

      Cai, Wenyan; Ji, Ying; Song, Xianping; Guo, Haoran; Han, Lei; Zhang, Feng; Liu, Xin; Zhang, Hengdong; Zhu, Baoli; Xu, Ming

      2017-10-01

      Correlation between exposure to glyphosate and sperm concentrations is important in reproductive toxicity risk assessment for male reproductive functions. Many studies have focused on reproductive toxicity on glyphosate, however, results are still controversial. We conducted a systematic review of epidemiological studies on the association between glyphosate exposure and sperm concentrations of rodents. The aim of this study is to explore the potential adverse effects of glyphosate on reproductive function of male rodents. Systematic and comprehensive literature search was performed in MEDLINE, TOXLINE, Embase, WANFANG and CNKI databases with different combinations of glyphosate exposure and sperm concentration. 8 studies were eventually identified and random-effect model was conducted. Heterogeneity among study results was calculated via chi-square tests. Ten independent experimental datasets from these eight studies were acquired to synthesize the random-effect model. A decrease in sperm concentrations was found with mean difference of sperm concentrations(MDsperm)=-2.774×10 6 /sperm/g/testis(95%CI=-0.969 to -4.579) in random-effect model after glyphosate exposure. There was also a significant decrease after fitting the random-effect model: MDsperm=-1.632×10 6 /sperm/g/testis (95%CI=-0.662 to -2.601). The results of meta-analysis support the hypothesis that glyphosate exposure decreased sperm concentration in rodents. Therefore, we conclude that glyphosate is toxic to male rodent's reproductive system. Copyright © 2017. Published by Elsevier B.V.

    6. Subcellular binding of 239Pu in the liver of selected species of rodents

      International Nuclear Information System (INIS)

      Winter, R.

      1980-01-01

      The subcellular distribution of 239 Pu in the liver of selected rodent species was investigated as well as the relation between 239 Pu and the iron metabolism. The goal of the investigation was to find out why the liver discharge of 239 Pu from the liver varies so much between species. (orig.) [de

    7. Population ecology of rodents of maize fields and grassland in central Ethiopia

      DEFF Research Database (Denmark)

      Bekel'e, Afework; Leirs, Herwig

      1997-01-01

      of A.dembeensis reached high values in the grassland. Breeding was seasonal and related to rainfall periods: extended rainy seasons resulting in longer periods with breeding females and higher litter sizes and, consequently, population size increases. These observations suggest that rodent population...

    8. Effect of Room Ventilation Rates in Rodent Rooms with Direct-Exhaust IVC Systems.

      Science.gov (United States)

      Geertsema, Roger S; Lindsell, Claire E

      2015-09-01

      When IVC are directly exhausted from a rodent housing room, the air quality of the room can become independent of the intracage air quality and may reduce the need for high room ventilation rates. This study assessed the effect of decreasing the ventilation rate in rodent rooms using direct-exhaust IVC systems. The study was conducted over 16 wk and compared conditions in 8 rodent rooms that had ventilation rates of 5 to 6 air changes per hour (ACH) with those in rooms at 10 to 12 ACH. At the low ventilation rate, rooms had higher CO₂ concentrations, higher dew point temperature, and lower particulate levels and spent a greater percentage of time above the temperature set point than did rooms at the high rate. The levels of allergens and endotoxins in room air were the same regardless of the ventilation rate. Differences seen in parameters within cages at the 2 ventilation rates were operationally irrelevant. We detected no total volatile organic compounds in the room that were attributable to ammonia, regardless of the ventilation rate. Clearing the air of ethanol after a spill took longer at the low compared with high rate. However, ethanol clearance was faster at the low rate when the demand-control system was activated than at the high ventilation rate alone. Air quality in the room and in the cages were acceptable with room ventilation rates of 5 to 6 ACH in rodent rooms that use direct-exhaust IVC systems.

    9. Genetic Rodent Models of Obesity-Associated Ovarian Dysfunction and Subfertility: Insights into Polycystic Ovary Syndrome

      Science.gov (United States)

      Huang-Doran, Isabel; Franks, Stephen

      2016-01-01

      Polycystic ovary syndrome (PCOS) is the most common endocrinopathy affecting women and a leading cause of female infertility worldwide. Defined clinically by the presence of hyperandrogenemia and oligomenorrhoea, PCOS represents a state of hormonal dysregulation, disrupted ovarian follicle dynamics, and subsequent oligo- or anovulation. The syndrome’s prevalence is attributed, at least partly, to a well-established association with obesity and insulin resistance (IR). Indeed, the presence of severe PCOS in human genetic obesity and IR syndromes supports a causal role for IR in the pathogenesis of PCOS. However, the molecular mechanisms underlying this causality, as well as the important role of hyperandrogenemia, remain poorly elucidated. As such, treatment of PCOS is necessarily empirical, focusing on symptom alleviation. The generation of knockout and transgenic rodent models of obesity and IR offers a promising platform in which to address mechanistic questions about reproductive dysfunction in the context of metabolic disease. Similarly, the impact of primary perturbations in rodent gonadotrophin or androgen signaling has been interrogated. However, the insights gained from such models have been limited by the relatively poor fidelity of rodent models to human PCOS. In this mini review, we evaluate the ovarian phenotypes associated with rodent models of obesity and IR, including the extent of endocrine disturbance, ovarian dysmorphology, and subfertility. We compare them to both human PCOS and other animal models of the syndrome (genetic and hormonal), explore reasons for their discordance, and consider the new opportunities that are emerging to better understand and treat this important condition. PMID:27375552

    10. Kinship structure and mating system in a solitary subterranean rodent, the silvery mole-rat

      Czech Academy of Sciences Publication Activity Database

      Patzenhauerová, Hana; Bryja, Josef; Šumbera, R.

      2010-01-01

      Roč. 64, č. 5 (2010), s. 757-767 ISSN 0340-5443 R&D Projects: GA AV ČR IAA601410802 Institutional research plan: CEZ:AV0Z60930519 Keywords : subterranean rodent * kinship structure * mating system * dispersal Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.565, year: 2010

    11. Gastrointestinal parasites in feral cats and rodents from the Fernando de Noronha Archipelago, Brazil

      Directory of Open Access Journals (Sweden)

      Victor Fernando Santana Lima

      2017-11-01

      Full Text Available Abstract Gastrointestinal parasites are important pathogens affecting animals, some of them are of medical and veterinary concern. Although the dynamic of parasitic infections is a complex phenomenon that has been studied under experimental conditions, it shows several gaps in knowledge, especially in insular regions where a confined population of animals and parasites co-exists. In this study was assessed the parasitism by endoparasite gastrointestinal in feral cats (n = 37 and rodents (n = 30 from the Fernando de Noronha Archipelago; in addition, the risk of human infection and ecological implications of these findings were discussed. Out of all samples analysed, 100% scored positive for the presence of gastrointestinal parasites in both feral cats and rodents. A total 17 genera and/or species of endoparasite gastrointestinal were identified, Ancylostoma sp., Strongyloides sp., Trichuris campanula and Toxocara cati were the parasites more frequently in feral cats. In rodents Eimeria sp., Strongyloides sp. and Trichuris muris were parasites more frequently herein detected. Human population living in this area are at risk of parasite infections due to the population of rodents and feral cats in the archipelago.

    12. The rodent estrous cycle: Characterization of vaginal cytology and its utility in toxicological studies

      Science.gov (United States)

      An evaluation of the estrous cycle in laboratory rodents can be a useful measure of the integrity of the hypothalamic-pituitary-ovarian reproductive axis. It can also serve as a way of insuring that animals exhibiting abnormal cycling patterns are disincluded from a study prior t...

    13. RODENT LEYDIG CELL TUMORIGENESIS: A REVIEW OF THE PHYSIOLOGY, PATHOLOGY, MECHANISMS, AND RELEVANCE TO HUMANS

      Science.gov (United States)

      Leydig cells (LCs) are the cells of the testis that have as their primary function the production of testosterone. LCs are a common target of compounds tested in rodent carcinogenicity bioassays. The number of reviews on Leydig cell tumors (LCTs) has increased in recent years bec...

    14. Muleshoe Virus and Other Hantaviruses Associated with Neotomine or Sigmodontine Rodents in Texas.

      Science.gov (United States)

      Milazzo, Mary Louise; Cajimat, Maria N B; Richter, Martin H; Bradley, Robert D; Fulhorst, Charles F

      2017-10-01

      The broad objective of this study was to increase our knowledge of Muleshoe virus and other hantaviruses associated with cricetid rodents in Texas. Anti-hantavirus antibody was found in 38 (3.2%) of 1171 neotomine rodents and 6 (1.8%) of 332 sigmodontine rodents from 10 Texas counties; hantaviral RNA was detected in 23 (71.9%) of 32 antibody-positive rodents. Analyses of nucleocapsid protein gene sequences indicated Muleshoe virus infection in four hispid cotton rats (Sigmodon hispidus) from northern Texas; Bayou virus, three Texas marsh oryzomys (Oryzomys texensis) from the Gulf Coast; Limestone Canyon virus, five brush mice (Peromyscus boylii) from western Texas; and Sin Nombre virus-five Texas mice (P. attwateri), one Lacey's white-ankled deer mouse (P. laceianus), four white-footed mice (P. leucopus), and one fulvous harvest mouse (Reithrodontomys fulvescens) from northern, central, or southern Texas. The results of this study together with the results of a previous study revealed that Muleshoe virus, perhaps in association with S. hispidus, is distributed across northern Texas. Finally, the results of Bayesian analyses of glycoprotein precursor (GPC) gene sequences and pairwise comparisons of complete GPC (amino acid) sequences strengthened support for the notion that Muleshoe virus is distinct from Black Creek Canal virus, Bayou virus, and all other species included in the Bunyaviridae, genus Hantavirus.

    15. Effects of rodent community diversity and composition on prevalence of an endemic bacterial pathogen - Bartonella

      Science.gov (United States)

      Bai, Y.; Kosoy, M.Y.; Calisher, C.H.; Cully, J.F.; Collinge, S.K.

      2009-01-01

      By studying Bartonella prevalence in rodent communities from 23 geographic sites in the western United States and one site in northern Mexico, the present study focused on the effects of rodent community diversity (measured by richness and Shannon index) and composition on prevalence of Bartonella infections. The analysis showed negative correlations of Bartonella prevalence with rodent richness and Shannon index. Further, Bartonella prevalence varied among rodent genera/species. Three models were applied to explain the observations. (1) Within-species/genus transmission: Bartonella strains usually are host-specific and adding non-host species would decrease Bartonella prevalence in its principal host through reduction of host contact (encounter reduction); (2) Frequency-dependence: Adding hosts would decrease the proportion of all infected individuals in the community, resulting in a reduction in the number of contacts between susceptible and infected individuals that usually leads to transmission (transmission reduction); and (3) Dominant species effect: Dominant species, if not susceptible to Bartonellae, can constrain the abundance of susceptible hosts (susceptible host regulation). These mechanisms work in concert; and the level of Bartonella prevalence is an outcome of regulation of all of these mechanisms on the entire system.

    16. The role of granivorous rodents in beech forest regeneration in the Beskydy Mts. (Czech Republic)

      Czech Academy of Sciences Publication Activity Database

      Heroldová, Marta; Suchomel, J.; Purchart, L.; Homolka, Miloslav

      2008-01-01

      Roč. 1, č. 2 (2008), s. 131-134 ISSN 1803-2451 R&D Projects: GA MZe QH72075 Institutional research plan: CEZ:AV0Z60930519 Keywords : beech mast biomass * granivorous rodents * daily consumption rate * mountain beech forest * regeneration Subject RIV: EH - Ecology, Behaviour

    17. Wheat or barley? Feeding preferences affect distribution of three rodent species in agricultural landscape

      Czech Academy of Sciences Publication Activity Database

      Heroldová, Marta; Tkadlec, E.; Bryja, Josef; Zejda, J.

      2008-01-01

      Roč. 110, 3-4 (2008), s. 354-362 ISSN 0168-1591 R&D Projects: GA ČR GA206/04/2003 Institutional research plan: CEZ:AV0Z60930519 Keywords : agro-ecosystem * small rodent species * diet preference * habitat preference Subject RIV: EH - Ecology, Behaviour Impact factor: 1.823, year: 2008

    18. A Theoretical and Experimental Investigation of Mechanical Damage to Rodent Sperm Generated by Microscale Ice Formation.

      Science.gov (United States)

      Han, X; Critser, J K

        BACKGROUND: Rodent sperm cryopreservation is of critical importance for the maintenance of lines or strains of genetically engineered mice and rats. However, rodent sperm are extremely mechanically sensitive due to their unusual morphology, and are severely damaged using current methods of cryopreservation. Those methods result in poor post thaw motility (PTM) for mouse. To investigate the mechanism of mechanical damage introduced to rodent sperm during freezing, a micro-mechanical model was established to analyze the sperm radial and axial thermal stresses generated by microscale extracellular ice formation. PTM of mouse sperm cryopreserved in capillaries of different radii (100, 200, 344, 526, 775µm) was measured using a standard computer-assisted sperm analysis system. The model predicts that when one of the inner dimensions of the containers (the inner diameter of plastic straws or straw capillaries) is on the same order of magnitude of sperm length, axial stress is significantly increased. The experimental results showed that the value of PTM was decreased from 38 ± 8 % in the larger (775µm) capillaries to 0 ± 0 % in the smaller (100 µm) ones. Theoretical analysis based on the established model were experimentally validated and can be used to guide the design of novel devices to improve the efficiency of rodent sperm cryopreservation.

    19. Genetic identification of Iberian rodent species using both mitochondrial and nuclear loci: application to noninvasive sampling.

      Science.gov (United States)

      Barbosa, S; Pauperio, J; Searle, J B; Alves, P C

      2013-01-01

      Species identification through noninvasive sampling is increasingly used in animal conservation genetics, given that it obviates the need to handle free-living individuals. Noninvasive sampling is particularly valuable for elusive and small species such as rodents. Although rodents are not usually assumed to be the most obvious target for conservation, of the 21 species or near-species present in Iberia, three are considered endangered and declining, while several others are poorly studied. Here, we develop a genetic tool for identifying all rodent species in Iberia by noninvasive genetic sampling. To achieve this purpose, we selected one mitochondrial gene [cytochrome b (cyt-b)] and one nuclear gene [interphotoreceptor retinoid-binding protein (IRBP)], which we first sequenced using tissue samples. Both genes allow for the phylogenetic distinction of all species except the sibling species Microtus lusitanicus and Microtus duodecimcostatus. Overall, cyt-b showed higher resolution than IRBP, revealing a clear barcoding gap. To allow these markers to be applied to noninvasive samples, we selected a short highly diagnostic fragment from each gene, which we used to obtain sequences from faeces and bones from owl pellets. Amplification success for the cyt-b and IRBP fragment was 85% and 43% in faecal and 88% and 64% in owl-pellet DNA extractions, respectively. The method allows the unambiguous identification of the great majority of Iberian rodent species from noninvasive samples, with application in studies of distribution, spatial ecology and population dynamics, and for conservation. © 2012 Blackwell Publishing Ltd.

    20. Gastrointestinal parasites in feral cats and rodents from the Fernando de Noronha Archipelago, Brazil.

      Science.gov (United States)

      Lima, Victor Fernando Santana; Ramos, Rafael Antonio Nascimento; Lepold, Raphael; Borges, João Carlos Gomes; Ferreira, Carlos Diógenes; Rinaldi, Laura; Cringoli, Giuseppe; Alves, Leucio Câmara

      2017-01-01

      Gastrointestinal parasites are important pathogens affecting animals, some of them are of medical and veterinary concern. Although the dynamic of parasitic infections is a complex phenomenon that has been studied under experimental conditions, it shows several gaps in knowledge, especially in insular regions where a confined population of animals and parasites co-exists. In this study was assessed the parasitism by endoparasite gastrointestinal in feral cats (n = 37) and rodents (n = 30) from the Fernando de Noronha Archipelago; in addition, the risk of human infection and ecological implications of these findings were discussed. Out of all samples analysed, 100% scored positive for the presence of gastrointestinal parasites in both feral cats and rodents. A total 17 genera and/or species of endoparasite gastrointestinal were identified, Ancylostoma sp., Strongyloides sp., Trichuris campanula and Toxocara cati were the parasites more frequently in feral cats. In rodents Eimeria sp., Strongyloides sp. and Trichuris muris were parasites more frequently herein detected. Human population living in this area are at risk of parasite infections due to the population of rodents and feral cats in the archipelago.

    1. A systematic review of discomfort due to toe or ear clipping in laboratory rodents

      NARCIS (Netherlands)

      Wever, K.E.; Geessink, F.J.; Brouwer, M.A.E.; Tillema, A.; Ritskes-Hoitinga, M.

      2017-01-01

      Toe clipping and ear clipping (also ear notching or ear punching) are frequently used methods for individual identification of laboratory rodents. These procedures potentially cause severe discomfort, which can reduce animal welfare and distort experimental results. However, no systematic summary of

    2. Rodent Abundance and Hantavirus Infection in Protected Area, East-Central Argentina

      Science.gov (United States)

      Maroli, Malena; Vadell, María Victoria; Padula, Paula

      2018-01-01

      We captured 3 hantavirus rodent hosts in Otamendi Natural Reserve, Argentina, during 2007–2012. Hantavirus antibodies were found only in Akodon azarae grass mice, mainly in males and old animals. Higher abundance of this species was associated with warm and rainy weather and high water levels, which peaked after a strong El Niño event. PMID:29260665

    3. A Functional Analysis of Circadian Pacemakers in Nocturnal Rodents. IV. Entrainment : Pacemaker as Clock

      NARCIS (Netherlands)

      Pittendrigh, Colin S.; Daan, Serge

      1976-01-01

      1. In the first part of the paper, the model of non-parametric entrainment of circadian pacemakers is tested for the case of nocturnal rodents. The model makes use of the available data on freerunning period (τ) in constant darkness and on phase response curves (PRC) for short light pulses. It is

    4. A rationally designed monomeric peptide triagonist corrects obesity and diabetes in rodents

      DEFF Research Database (Denmark)

      Finan, Brian; Yang, Bin; Ottaway, Nickki

      2015-01-01

      -in-class monoagonists to reduce body weight, enhance glycemic control and reverse hepatic steatosis in relevant rodent models. Various loss-of-function models, including genetic knockout, pharmacological blockade and selective chemical knockout, confirmed contributions of each constituent activity in vivo. We...

    5. Detection of Orientia sp. DNA in rodents from Asia, West Africa and Europe.

      Science.gov (United States)

      Cosson, Jean François; Galan, Maxime; Bard, Emilie; Razzauti, Maria; Bernard, Maria; Morand, Serge; Brouat, Carine; Dalecky, Ambroise; Bâ, Khalilou; Charbonnel, Nathalie; Vayssier-Taussat, Muriel

      2015-03-21

      Orientia bacterium is the agent of the scrub typhus, a seriously neglected life-threatening disease in Asia. Here, we report the detection of DNA of Orientia in rodents from Europe and Africa. These findings have important implications for public health. Surveillance outside Asia, where the disease is not expected by sanitary services, needs to be improved.

    6. Long-lived cancer-resistant rodents as new model species for cancer research

      Directory of Open Access Journals (Sweden)

      Jorge eAzpurua

      2013-01-01

      Full Text Available Most rodents are small and short-lived, but several lineages have independently evolved long lifespans without a concomitant increase in body mass. Most notably, the two subterranean species naked mole rat (NMR and blind mole rat (BMR which have maximum lifespans of 32 and 21 years respectively. The longevity of these species has sparked interest in the tumor suppression strategies that may have also evolved, because for many rodent species (including mice, rats, guinea pigs, gerbils and hamsters tumors are major source of late-life mortality. Here, we review the recent literature on anticancer mechanisms in long-lived rodents. Both NMR and BMR seem to have developed tumor defenses that rely on extra-cellular signals. However, while the NMR relies on a form of contact inhibition to suppress growth, the BMR evolved a mechanism mediated by the release of interferon and rapid necrotic cell death. Although both organisms ultimately rely on canonical downstream tumor suppressors (pRB and p53 the studies reveal species can evolve different strategies to achieve tumor-resistance. Importantly, studies of these cancer-resistant rodents may benefit human health if such mechanisms can be activated in human cells.

    7. A microhistological technique for analysis of food habits of mycophagous rodents.

      Science.gov (United States)

      Patrick W. McIntire; Andrew B. Carey

      1989-01-01

      We present a technique, based on microhistological analysis of fecal pellets, for quantifying the diets of forest rodents. This technique provides for the simultaneous recording of fungal spores and vascular plant material. Fecal samples should be freeze dried, weighed, and rehydrated with distilled water. We recommend a minimum sampling intensity of 50 fields of view...

    8. Functional recovery after facial nerve cable grafting in a rodent model.

      NARCIS (Netherlands)

      Hohman, M.H.; Kleiss, I.J.; Knox, C.J.; Weinberg, J.S.; Heaton, J.T.; Hadlock, T.A.

      2014-01-01

      IMPORTANCE: Cable grafting is widely considered to be the preferred alternative to primary repair of the injured facial nerve; however, quantitative comparison of the 2 techniques has not been previously undertaken in a rodent model. OBJECTIVE: To establish functional recovery parameters after

    9. A multiplex panel of microsatellite markers for widespread subsaharan rodents of the genus Mastomys

      NARCIS (Netherlands)

      Galan, M.; Hooft, van W.F.; Legrand, D.; Berthier, K.; Loiseau, A.; Granjon, L.; Cosson, J.F.

      2004-01-01

      We isolated and characterized 12 polymorphic microsatellite loci in the sub-Saharan rodent Mastomys huberti. We tested cross-species amplification of all these loci in three closely related Mastomys species: M. coucha, M. erythroleucus and M. natalensis. Multiplex panels comprising 11 loci were

    10. Oleoresin Capsicum has Potential as a Rodent Repellent in Direct Sedding Longleaf Pine

      Science.gov (United States)

      James P. Barnett

      1998-01-01

      Direct seeding of southern pines has been a versatile and inexpensive alternative to planting on many reforestation sites across the South. Successful direct seeding has required that seeds be coated with thiram to repel birds, and with endrin to repel rodents. Endrin, which is extremely toxic, is no longer produced in the United States. Therefore, a substitute is...

    11. Rodent movements, densities and radionuclide concentrations at a liquid radioactive waste disposal area

      International Nuclear Information System (INIS)

      Halford, D.K.

      1983-01-01

      Movements and densities of rodents at a liquid radioactive waste disposal area were studied from June to September 1981 using trap line and assessment line techniques. The average distance between points of successive capture was 42 +- 25 (SD) m for deer mice (Peromyscus maniculatus) and 37 +- 21 m for kangaroo rats (Dipodomys ordii). Densities of deer mice averaged 10.2/ha with a population estimate of 57 within the area of rodent captures. The population estimate of 4 species of small mammals at the waste pond complex was 93. Radionuclide concentrations averaged 133 +- 97 pCi/g for rodents captured inside the disposal area boundary, 18 +- 22 pCi/g for those captured outside of the dispoal area fence and 0.50 +- 0.6 pCi/g for control animals. Species captured outside of the waste area boundary had significantly lower (P 137 Cs, 134 Cs, 60 Co and 65 Zn) in rodents at the liquid waste disposal area was estimated to be about 162 nCi

    12. Rare variant analysis of human and rodent obesity genes in individuals with severe childhood obesity

      DEFF Research Database (Denmark)

      Hendricks, Audrey E.; Bochukova, Elena G.; Marenne, Gaëlle

      2017-01-01

      Obesity is a genetically heterogeneous disorder. Using targeted and whole-exome sequencing, we studied 32 human and 87 rodent obesity genes in 2,548 severely obese children and 1,117 controls. We identified 52 variants contributing to obesity in 2% of cases including multiple novel variants in GN...

    13. Endotoxin, coliform, and dust levels in various types of rodent bedding.

      Science.gov (United States)

      Whiteside, Tanya E; Thigpen, Julius E; Kissling, Grace E; Grant, Mary G; Forsythe, Diane

      2010-03-01

      Endotoxins in grain dust, household dust, and animal bedding may induce respiratory symptoms in rodents and humans. We assayed the endotoxin, coliform, and dust levels in 20 types of rodent bedding. Endotoxin concentrations were measured by using a commercial test kit, coliform counts were determined by using conventional microbiologic procedures, and dust content was evaluated by using a rotating-tapping shaker. Paper bedding types contained significantly less endotoxin than did other bedding types; the highest levels of endotoxin were detected in hardwood and corncob beddings. The range of endotoxin content for each bedding type was: corncob bedding, 1913 to 4504 endotoxin units per gram (EU/g); hardwood bedding, 3121 to 5401 EU/g; corncob-paper mixed bedding, 1586 to 2416 EU/g; and paper bedding, less than 5 to 105 EU/g. Coliform counts varied from less than 10 to 7591 cfu/g in corncob beddings, 90 to 4010 cfu/g in corncob-paper mixed beddings, less than 10 to 137 cfu/g in hardwood beddings, and less than 10 cfu/g in paper beddings. Average dust content was less than 0.15% in all commercial bedding types. We conclude that paper bedding is the optimal bedding type for conducting LPS inhalation studies and that rodent bedding containing high levels of endotoxin may alter the results of respiratory and immunologic studies in rodents.

    14. distribution and abundance of rodents in farmlands: a case study in ...

      African Journals Online (AJOL)

      ADMIN

      eruption (Pech et al., 1999). Rodent damage is rarely uniform in time; it follows crop phenology. Rice field rats cause more damage during some stages of growth of paddy than during other stages (Tristiani and Murakami,. 1998). Multimammate mice dig up planted maize seeds, but are harmless during the growth of maize.

    15. Plantões jovens: acolhimento e cuidado por meio da educação entre pares para adolescentes e jovens nos Centros de Testagem e Aconselhamento - CTA Youths on duty: reception and care for adolescents and young people at testing and counselling centres

      Directory of Open Access Journals (Sweden)

      Gabriela Calazans

      2006-04-01

      Full Text Available O Brasil encontra-se com a maior população jovem de sua história. Há um fator agravante para a difícil situação que enfrentam os jovens brasileiros, pois eles vivem em regiões de maior vulnerabilidade social. Estes jovens têm necessidades específicas e devem ser desenvolvidas políticas públicas que respondam a sua especificidade, dentro de uma perspectiva que encoraje a participação. Uma estratégia inovadora na perspectiva da educação entre pares foi desenvolvida no âmbito dos Centros de Testagem e Aconselhamento (CTA vinculados à Secretaria Municipal da Saúde de São Paulo, denominada Plantão Jovem (PJ. Os PJ são formados por jovens entre 16 e 24 anos, que atuam junto a seus pares em ações de acolhimento, aconselhamento, oferta de insumos e de palestras educativas. Este artigo descreve os PJ, na perspectiva de seus jovens agentes, buscando compreender como estes compreendem o seu trabalho de educação entre pares. Foram desenvolvidos 3 grupos focais com os plantonistas de quatro CTA implantados em regiões periféricas e de alta exclusão social. Os discursos dos plantonistas valorizam a identidade com os jovens de sua comunidade no desenvolvimento de ações individuais e coletivas, a ênfase no aprendizado prático, o enfoque no encontro e no entendimento do outro. Foram identificados alguns pontos de tensão no desenvolvimento da proposta: valorização da informação técnico-científica X centralidade do encontro e do diálogo, no âmbito da prevenção de Aids; confusão entre identidade pessoal e profissional, como paradoxo da educação entre pares; confusão entre agentes e técnica operacionalizada no contexto da educação entre pares.Brazil is facing its major youth population of its history. There is an aggravation for the difficult situation met by young Brazilians nowadays, because they live in regions submitted to great social vulnerability. Young people have specific needs and public policies must be

    16. Basement membrane proteoglycans are of epithelial origin in rodent skin

      DEFF Research Database (Denmark)

      Yamane, Y; Yaoita, H; Couchman, J R

      1996-01-01

      . For in vivo experiments, pieces of newborn rat epidermis obtained by dispase treatment were grafted onto athymic nude mice. Three and six weeks after grafting, immunofluorescence analysis of the grafted skin was carried out, using monoclonal antibodies specific for rat basement membrane chondroitin sulfate...

    17. Mathematical modeling of sleep state dynamics in a rodent model of shift work

      Directory of Open Access Journals (Sweden)

      Michael J. Rempe

      2018-06-01

      Full Text Available Millions of people worldwide are required to work when their physiology is tuned for sleep. By forcing wakefulness out of the body’s normal schedule, shift workers face numerous adverse health consequences, including gastrointestinal problems, sleep problems, and higher rates of some diseases, including cancers. Recent studies have developed protocols to simulate shift work in rodents with the intention of assessing the effects of night-shift work on subsequent sleep (Grønli et al., 2017. These studies have already provided important contributions to the understanding of the metabolic consequences of shift work (Arble et al., 2015; Marti et al., 2016; Opperhuizen et al., 2015 and sleep-wake-specific impacts of night-shift work (Grønli et al., 2017. However, our understanding of the causal mechanisms underlying night-shift-related sleep disturbances is limited. In order to advance toward a mechanistic understanding of sleep disruption in shift work, we model these data with two different approaches. First we apply a simple homeostatic model to quantify differences in the rates at which sleep need, as measured by slow wave activity during slow wave sleep (SWS rises and falls. Second, we develop a simple and novel mathematical model of rodent sleep and use it to investigate the timing of sleep in a simulated shift work protocol (Grønli et al., 2017. This mathematical framework includes the circadian and homeostatic processes of the two-process model, but additionally incorporates a stochastic process to model the polyphasic nature of rodent sleep. By changing only the time at which the rodents are forced to be awake, the model reproduces some key experimental results from the previous study, including correct proportions of time spent in each stage of sleep as a function of circadian time and the differences in total wake time and SWS bout durations in the rodents representing night-shift workers and those representing day-shift workers

    18. Effects of anatomy and diet on gastrointestinal pH in rodents.

      Science.gov (United States)

      Kohl, Kevin D; Stengel, Ashley; Samuni-Blank, Michal; Dearing, M Denise

      2013-04-01

      The pH of the gastrointestinal tract can have profound influences on digestive processes. Rodents exhibit wide variation in both stomach morphology and dietary strategies, both of which may influence gut pH. Various rodent species have evolved bilocular (or semi-segmented) stomachs that may allow for more microbial growth compared to unilocular (single-chambered) stomachs. Additionally, herbivory has evolved multiple times in rodents. The high dietary fiber typical of an herbivorous diet is known to induce secretion of bicarbonate in the gut. We predicted that stomach segmentation might facilitate the separation of contents in the proximal chamber from that of the gastric stomach, facilitating a chemical environment suitable to microbial growth. To investigate the effect of stomach anatomy and diet on gut pH, several species of rodent with varying stomach morphology were fed either a high or low-fiber diet for 7 days, and pH of the proximal stomach, gastric stomach, small intestine, and cecum were measured. We discovered that rodents with bilocular stomach anatomy maintained a larger pH gradient between the proximal and gastric stomach compartments, and were able to achieve a lower absolute gastric pH compared to those with unilocular stomachs. Dietary fiber increased the pH of the small intestine, but not in any other gut regions. The stomach pH data supports the century old hypothesis that bilocular stomach anatomy creates an environment in the proximal stomach that is suitable for microbial growth. Additionally, the alkaline small intestinal pH on a high fiber diet may enhance digestion. Copyright © 2013 Wiley Periodicals, Inc.

    19. Ecology, genetic diversity, and phylogeographic structure of andes virus in humans and rodents in Chile.

      Science.gov (United States)

      Medina, Rafael A; Torres-Perez, Fernando; Galeno, Hector; Navarrete, Maritza; Vial, Pablo A; Palma, R Eduardo; Ferres, Marcela; Cook, Joseph A; Hjelle, Brian

      2009-03-01

      Andes virus (ANDV) is the predominant etiologic agent of hantavirus cardiopulmonary syndrome (HCPS) in southern South America. In Chile, serologically confirmed human hantavirus infections have occurred throughout a wide latitudinal distribution extending from the regions of Valparaíso (32 to 33 degrees S) to Aysén (46 degrees S) in southern Patagonia. In this study, we found seropositive rodents further north in the Coquimbo region (30 degrees S) in Chile. Rodent seroprevalence was 1.4%, with Oligoryzomys longicaudatus displaying the highest seroprevalence (5.9%), followed by Abrothrix longipilis (1.9%) and other species exhibiting Chile. Phylogenetic analyses showed two major ANDV South (ANDV Sout) clades, congruent with two major Chilean ecoregions, Mediterranean (Chilean matorral [shrubland]) and Valdivian temperate forest. Human and rodent samples grouped according to geographic location. Phylogenetic comparative analyses of portions of S and medium segments (encoding glycoproteins Gn and Gc) from a subset of rodent specimens exhibited similar topologies, corroborating two major ANDV Sout clades in Chile and suggesting that yet unknown factors influence viral gene flow and persistence throughout the two Chilean ecoregions. Genetic algorithms for recombination detection identified recombination events within the S segment. Molecular demographic analyses showed that the virus is undergoing purifying selection and demonstrated a recent exponential growth in the effective number of ANDV Sout infections in Chile that correlates with the increased number of human cases reported. Although we determined virus sequences from four rodent species, our results confirmed O. longicaudatus as the primary ANDV Sout reservoir in Chile. While evidence of geographic differentiation exists, a single cosmopolitan lineage of ANDV Sout remains the sole etiologic agent for HCPS in Chile.

    20. Integrative rodent models for assessing male reproductive toxicity of environmental endocrine active substances

      Directory of Open Access Journals (Sweden)

      Jacques Auger

      2014-02-01

      Full Text Available In the present review, we first summarize the main benefits, limitations and pitfalls of conventional in vivo approaches to assessing male reproductive structures and functions in rodents in cases of endocrine active substance (EAS exposure from the postulate that they may provide data that can be extrapolated to humans. Then, we briefly present some integrated approaches in rodents we have recently developed at the organism level. We particularly focus on the possible effects and modes of action (MOA of these substances at low doses and in mixtures, real-life conditions and at the organ level, deciphering the precise effects and MOA on the fetal testis. It can be considered that the in vivo experimental EAS exposure of rodents remains the first choice for studies and is a necessary tool (together with the epidemiological approach for understanding the reproductive effects and M