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Sample records for em hamsters mesocricetus

  1. Cutaneous myxosarcoma in a Syrian hamster (Mesocricetus auratusMixossarcoma cutâneo em um Hamster Sírio

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    Renée Laufer Amorim

    2011-08-01

    Full Text Available The pathological findings in a 2-years-old Syrian hamster (Mesocricetus auratus with a cutaneous myxosarcoma are described. Grossly, there was a large cutaneous mass in the right cervical region. Microscopical evaluation revealed a myxosarcoma characterized by pleomorphic, fusiform cells loosely arranged, randomly distributed, and presenting a moderate amount of basophilic amorphous stroma. There were hemorrhagic areas within the tumor. The basophilic amorphous stroma was positive to Alcian blue confirming the presence of a mucopolysaccharide matrix. Immunohistochemically, the neoplastic cells expressed vimentin, and were negative for cytokeratin or glial fibrillary acidic protein (GFAP.São descritos os achados anatomopatológicos de um caso de mixossarcoma cutâneo em um Hamster Sírio de 2 anos de idade. Macroscopicamente, foi evidenciada um grande massa cutânea na região cervical lateral direita. A microscopia revelou a presença de um caso de mixossarcoma caracterizado por células fusiformes pleomórficas, frouxamente arranjadas, distribuídas aleatoriamente e, apresentando quantidade moderada de substância basofílica amorfa no estroma e áreas hemorrágicas. O estroma basofílico amorfo foi positivo na coloração Alcian blue, confirmando a presença de matriz mucopolissacarídea. Na imunoistoquímica, as células neoplásicas expressaram vimentina e foram negativas para a marcação de citoqueratina e proteína ácida fibrilar (GFAP.

  2. Morbidity due to Schistosoma mansoni - Entamoeba histolytica coinfection in hamsters (Mesocricetus auratus Morbidade em hamsters (Mesocricetus auratus devido à co-infecção Schistosoma mansoni - Entamoeba histolytica

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    Silvio Santana Dolabella

    2007-04-01

    Full Text Available Data on Schistosoma mansoni-Entamoeba histolytica coinfection are scarce in the literature. In the present study, hamsters that had been infected for 70 days with Schistosoma mansoni (LE strain were inoculated via the portal vein with two strains of trophozoites of Entamoeba histolytica: ICB-EGG (highly virulent and ICB-RPS (non-virulent. The most evident result of coinfection was increased morbidity and mortality, in comparison with either of the infections alone. Histologically, there were no evident signs of interaction between these two infections. The morphological findings of schistosomal granuloma and amoebic abscesses in the liver were similar to those seen in the respective single-infection controls. However, there was severe wasting of the animals with both infections and greater numbers of amoebic lesions in their livers. The results obtained indicated that schistosomiasis aggravates the course of amoebiasis in hamsters.Dados sobre a co-infecção Schistosoma mansoni-Entamoeba histolytica são escassos na literatura. No presente estudo, hamsters com 70 dias de infecção por Schistosoma mansoni (cepa LE foram inoculados com trofozoítos de Entamoeba histolytica, cepa ICB-EGG (virulenta e cepa ICB-RPS (não virulenta, via veia porta. O mais evidente resultado da co-infecção foi o aumento da morbidade e mortalidade, quando comparado com os animais com somente uma das infecções. Histologicamente, não houve sinais evidentes da interação entre as duas infecções. O aspecto morfológico do granuloma esquistossomótico e do abcesso hepático amebiano são similares aos observados nos controles, com somente uma infecção. Entretanto, foi observado que os animais co-infectados apresentavam-se mais debilitados e com maior número de lesões amebianas no fígado. Os resultados obtidos indicam que a esquistossomose agrava o curso da infecção amebiana em hamsters.

  3. Development of Taenia pisiformis in golden hamster (Mesocricetus auratus

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    Maravilla Pablo

    2011-07-01

    Full Text Available Abstract The life cycle of Taenia pisiformis includes canines as definitive hosts and rabbits as intermediate hosts. Golden hamster (Mesocricetus auratus is a rodent that has been successfully used as experimental model of Taenia solium taeniosis. In the present study we describe the course of T. pisiformis infection in experimentally infected golden hamsters. Ten females, treated with methyl-prednisolone acetate were infected with three T. pisiformis cysticerci each one excised from one rabbit. Proglottids released in faeces and adults recovered during necropsy showed that all animals were infected. Eggs obtained from the hamsters' tapeworms, were assessed for viability using trypan blue or propidium iodide stains. Afterwards, some rabbits were inoculated with eggs, necropsy was performed after seven weeks and viable cysticerci were obtained. Our results demonstrate that the experimental model of adult Taenia pisiformis in golden hamster can replace the use of canines in order to study this parasite and to provide eggs and adult tapeworms to be used in different types of experiments.

  4. Thyroid function and cold acclimation in the hamster, Mesocricetus auratus

    International Nuclear Information System (INIS)

    Tomasi, T.E.; Horwitz, B.A.

    1987-01-01

    Basal metabolic rate (BMR), thyroxine utilization rate (T 4 U), and triiodothyronine utilization rate (T 3 U) were measured in cold-acclimated (CA) and room temperature-acclimated (RA) male golden hamsters, Mesocricetus auratus. Hormone utilization rates were calculated via the plasma disappearance technique using 125 I-labeled hormones and measuring serum hormone levels via radioimmunoassay. BMR showed a significant 28% increase with cold acclimation. The same cold exposure also produced a 32% increase in T 4 U, and a 204% increase in T 3 U. The much greater increase in T 3 U implies that previous assessments of the relationship between cold acclimation and thyroid function may have been underestimated and that cold exposure induces both quantitative and qualitative changes in thyroid function. It is concluded that in the cold-acclimated state, T 3 U more accurately reflects thyroid function than does T 4 U. A mechanism for the cold-induced change in BMR is proposed

  5. Hamsters' (Mesocricetus auratus) memory in a radial maze analog: the role of spatial versus olfactory cues.

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    Tonneau, François; Cabrera, Felipe; Corujo, Alejandro

    2012-02-01

    The golden hamster's (Mesocricetus auratus) performance on radial maze tasks has not been studied a lot. Here we report the results of a spatial memory task that involved eight food stations equidistant from the center of a circular platform. Each of six male hamsters depleted the food stations along successive choices. After each choice and a 5-s retention delay, the hamster was brought back to the center of the platform for the next choice opportunity. When only one baited station was left, the platform was rotated to evaluate whether olfactory traces guided hamsters' choices. Results showed that despite the retention delay hamsters performed above chance in searching for food. The choice distributions observed during the rotation probes were consistent with spatial memory and could be explained without assuming guidance by olfactory cues. The radial maze analog we devised could be useful in furthering the study of spatial memory in hamsters.

  6. Estudio ultraestructural en testículo de hamster vasectomizado (Mesocricetus auratus)

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    Ureña, Francisco; Malavasi, Jollyana

    2016-01-01

    The ultrastructure of adult hamster (Mesocricetus auratus) testis was studied by means of light and electron microscopes during fourteen months after bilateral vasectomy. In all the vasectomized animals there was marked degeneration of the seminiferous tubules as well as reduction of spermatogenesis. The thickening of the basal membrane was quite evident and showed extensive infolding. In the Sertoli cells, the presence of spherical or oval membrane-bound granules, vacuoles and degenerating c...

  7. Topical treatment of experimental cutaneous leishmaniasis in golden hamster (Mesocricetus auratus) with formulations containing pentamidine

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    COMANDOLLI-WYREPKOWSKI, Claudia Dantas; GRAFOVA, Iryna; NAIFF, Maricleide de Farias; AVELLA, Maurizio; GENTILE, Gennaro; GRAFOV, Andriy; FRANCO, Antonia Maria Ramos

    2017-01-01

    ABSTRACT Current treatment of cutaneous leishmaniasis (CL) relies mainly on pentavalent antimonials salts and second-line drugs include pentamidine and amphotericin B, but these therapies have side effects and require parenteral administration. The aim of this work was to evaluate the topical formulations containing pentamidine isethionate (PI) in the experimental treatment of cutaneous leishmaniasis (CL). Golden hamsters (Mesocricetus auratus) were infected in the nose with Leishmania (Leish...

  8. Memory for individual scent in hamsters (Mesocricetus auratus) as assessed by habituation methods.

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    Johnston, R E

    1993-06-01

    The memory of hamsters (Mesocricetus auratus) for the flank scent of other male hamsters was investigated in a series of habituation experiments. In 2 types of habituation tasks (Experiments 1 and 2), male hamsters habituated to the flank scent of 1 male and then increased their level of investigation to that of a novel male; similar results were obtained when the intervals between trials ranged from 1 s to 2 days. When the test trial was 10 or 21 days after habituation (Experiment 3), males discriminated between familiar and novel flank scents at 10 days but not at 21 days. The results demonstrate recognition of familiar and unfamiliar individual odors and excellent memory for these differences. Habituation techniques yield extremely robust results and may be useful for investigations of other aspects of individual signatures.

  9. Enhanced longevity in tau mutant Syrian hamsters, Mesocricetus auratus

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    Oklejewicz, Malgorzata; Daan, Serge

    The single-gene mutation tau in the Syrian hamster shortens the circadian period by about 20% in the homozygous mutant and simultaneously increases the mass-specific metabolic rate by about 20%. Both effects might be expected to lead to a change in longevity. To test such expectations, the life span

  10. Persistence of experimental Rocio virus infection in the golden hamster (Mesocricetus auratus

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    Daniele Freitas Henriques

    2012-08-01

    Full Text Available Rocio virus (ROCV is an encephalitic flavivirus endemic to Brazil. Experimental flavivirus infections have previously demonstrated a persistent infection and, in this study, we investigated the persistence of ROCV infection in golden hamsters (Mesocricetus auratus. The hamsters were infected intraperitoneally with 9.8 LD50/0.02 mL of ROCV and later anaesthetised and sacrificed at various time points over a 120-day period to collect of blood, urine and organ samples. The viral titres were quantified by real-time-polymerase chain reaction (qRT-PCR. The specimens were used to infect Vero cells and ROCV antigens in the cells were detected by immunefluorescence assay. The levels of antibodies were determined by the haemagglutination inhibition technique. A histopathological examination was performed on the tissues by staining with haematoxylin-eosin and detecting viral antigens by immunohistochemistry (IHC. ROCV induced a strong immune response and was pathogenic in hamsters through neuroinvasion. ROCV was recovered from Vero cells exposed to samples from the viscera, brain, blood, serum and urine and was detected by qRT-PCR in the brain, liver and blood for three months after infection. ROCV induced histopathological changes and the expression of viral antigens, which were detected by IHC in the liver, kidney, lung and brain up to four months after infection. These findings show that ROCV is pathogenic to golden hamsters and has the capacity to cause persistent infection in animals after intraperitoneal infection.

  11. BODY WEIGHT AS A DETERMINANT OF CLINICAL EVOLUTION IN HAMSTERS (Mesocricetus auratus INFECTED WITH Leishmania (Viannia panamensis

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    Angela Maria Gomez-Galindo

    2013-09-01

    Full Text Available SUMMARY The clinical outcome of infection with Leishmania species of the subgenus Viannia in hamster model (Mesocricetus auratus has shown to be different depending on experimental protocol. Body weight has been a relevant determinant of the clinical outcome of the infection in hamsters with visceral leishmaniasis but its importance as a clinical parameter in hamsters with cutaneous leishmaniasis is not known. In this study, the clinical evolution of infection with L. (V panamensis was evaluated in juvenile and adult male hamsters during 11 weeks by comparing clinical parameters such as attitude, temperature, respiratory rate, appearance of the stool, and body weight between infected and non-infected groups. Results showed that body weight decreased in adult hamsters after infection by L. (V panamensis; this observation supports the use of body weight as an additional parameter to define the management or treatment of cutaneous leishmaniasis in infected adult hamsters used as an animal experimental model for leishmaniasis.

  12. Adolescent Anabolic/Androgenic Steroids: Aggression and Anxiety During Exposure Predict Behavioral Responding During Withdrawal in Syrian Hamsters (Mesocricetus auratus)

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    Ricci, Lesley A.; Morrison, Thomas R.; Melloni, Richard H.

    2013-01-01

    In the U.S. and worldwide anabolic/androgenic steroid use remains high in the adolescent population. This is concerning given that anabolic/androgenic steroid use is associated with a higher incidence of aggressive behavior during exposure and anxiety during withdrawal. This study uses pubertal Syrian hamsters (Mesocricetus auratus) to investigate the hypothesis that an inverse behavioral relationship exists between anabolic/androgenic steroid-induced aggression and anxiety across adolescent ...

  13. Validação de um radioimunoensaio para a quantificação de metabólitos fecais de testosterona em hamster Sírio (Mesocricetus auratus

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    Marie-Odile M Chelini

    2011-05-01

    Full Text Available Modelo para o estudo de diversas doenças humanas, o hamster tem sido objeto de numerosos estudos comportamentais e envolvendo estresse e/ou comportamento agonístico que supõem, muitas vezes, o monitoramento das flutuações hormonais nos indivíduos envolvidos. O objetivo do presente trabalho foi confirmar a adequação de um conjunto comercial para dosagem de testosterona em sangue humano para a quantificação de metabólitos fecais de testosterona (MFT em hamsters Sírios machos e fêmeas. Dez machos foram submetidos a um desafio com um agonista de GnRH para estimular a atividade testicular, elevando os níveis circulantes de testosterona. Cinco fêmeas receberam uma injeção de testosterona enquanto cinco outras receberam uma injeção de solução salina. Amostras de fezes coletadas antes e depois dos procedimentos, assim como amostras fecais de 20 fêmeas gestantes coletadas ao longo da gestação foram analisadas com um conjunto comercial para radioimunoensaio. Um pico de MFT 12h após a injeção seguido de uma queda abaixo do nível basal comprovou que, nos machos, as alterações nos níveis de MFT refletem as alterações da concentração de testosterona no sangue. Nestes observou-se um ciclo circadiano das concentrações de MFT com acrofase no início do período claro correspondendo ao ciclo descrito para as concentrações sanguíneas na literatura. Nas fêmeas a administração de testosterona exógena provocou uma elevação importante dos níveis de MFT, mas as concentrações medidas ao longo da gestação não refletiram o padrão dos níveis sanguíneos do hormônio endógeno. O conjunto para radioimunoensaio para testosterona em sangue humano mostrou-se adequado para o monitoramento da função testicular no hamster macho, mas um ensaio mais específico seria necessário para as fêmeas.

  14. Técnica para obtenção do aparelho geniturinário e dosagem do PSA (Prostate Specific Antigen no hamster sírio, Mesocricetus auratus Technique for collecting blood for PSA (Prostate Specific Antigen dosing and genitourinary system obtaining in syrian hamster, Mesocricetus auratus

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    Dimas José Araújo Vidigal

    2004-12-01

    Full Text Available Objetivo: Expor a técnica utilizada na colheita de sangue para dosagem do PSA ( Prostate Specific Antigen e retirada do aparelho geniturinário no hamster sírio, Mesocricetus auratus, e correlacionar os achados do PSA com as alterações histológicas dos anexos sexuais desse roedor. Métodos: Foram usados no experimento trinta (n= 30 Hamsters: dez (n=10 animais considerados jovens com idade média no momento da morte de 47,5 dias e vinte (n=20 animais considerados adultos com idade superior à um ano. Após serem anestesiados com cloridrato de quetamina e diazepam, foi colhido diretamente da veia cava, em nível de abdome superior, cerca de 1,5mL a 2,0mL de sangue para dosagem do PSA totalpelo método ELISA, com antígeno humano. Morriam após colheita do sangue. Constatado a morte do animal, fazia-se a laparotomia retirando-se em monobloco todo aparelho geniturinário para estudo histológico dos anexos sexuais. Correlacionou-se o PSA com as alterações histológicas encontradas. Resultados: Os animais após serem anestesiados com cloridrato de quetamina e diazepam intraperitonealmente, obteve-se um excelente plano anestésico, que possibilitou colher via trans-dérmica da veia cava inferior em abdome superior sangue para dosagem do PSA. O animal morria após colheita do sangue. Fazia-se a laparotomia, com retirada em monobloco do aparelho geniturinário para estudo histológico e comparação das alterações encontradas nos anexos sexuais com o PSA dosado. Entre os Hamsters Jovens a média do PSA encontrado foi de 0,252ng/mL. Desvio Padrão (DP = 0,36. Entre os Hamsters adultos esta média foi de 0,325 ng/mL, DP= 0,12 . Quando comparou-se as médias do PSA entre os dois grupos de jovens e adultos obteve-se p= 0,0427. Dentre os Hamsters jovens, três apresentaram PSA não detectado. A análise histológica mostrou que, entre os animais jovens, não foi identificada qualquer alteração das estruturas microscópicas da próstata, ves

  15. Hamster (Mesocricetus auratus cheek pouch as an experimental model to investigate human skin and keloid heterologous graft Bolsa jugal no hamster (Mesocricetus auratus como modelo experimental de investigação de enxertos heterólogos de pele humana e quelóide

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    Bernardo Hochman

    2004-12-01

    Full Text Available To describe the integration process of grafts of total human skin and keloid in hamster (Mesocricetus auratus cheek pouch, whose sub-epithelium is naturally an "Immunologically Privileged Site". Fragments of human normal skin and keloid from the breast region of mulatto female patients were transplanted into the cheek pouch subepithelium in situ. Surgical procedure and grafted pouches for microscopic exam at several time points of the transplantation were standardized. The integration of grafted fragments of human skin and keloid was seen in late periods (84 days since the microscopic assessment showed the presence of blood vases within the conjunctive tissue of grafted fragments. It was also possible to see among the grafted fragments the epithelium, the appearing of early cellular infiltrated, epithelial secretion of keratin, the presence of melanocytes, and delayed changes on the aspect of collagen fibers of conjunctive tissue. Pooled results allow to define hamster cheek pouch sub-epithelium as an experimental model to investigating heterologous graft physiology of human total skin and keloid with epithelium.Descrever a integração dos enxertos de pele total humana e quelóide na bolsa jugal do hamster (Mesocricetus auratus, cujo subepitélio é, naturalmente, um "Local de Privilégio Imunológico". Foram transplantados fragmentos, de pele humana normal e de quelóide, obtidos da região mamária de pacientes pardas, no subepitélio da bolsa jugal in situ. O procedimento operatório, e de preparo das bolsas enxertadas para exame microscópico em vários períodos de transplante, foi padronizado. Verificou-se a integração dos fragmentos enxertados de pele humana e de quelóide em períodos tardios (84 dias, uma vez que a avaliação microscópica revelou a presença de vasos sangüíneos no tecido conjuntivo dos fragmentos enxertados. Foi também possível observar, nos fragmentos enxertados, o epitélio, o aparecimento de infiltrado

  16. Seco-limonoid derived from Raputia heptaphylla promotes the control of cutaneous leishmaniasis in hamsters (Mesocricetus auratus).

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    Granados-Falla, Diana; Gomez-Galindo, Angela; Daza, Alejandro; Robledo, Sara; Coy-Barrera, Carlos; Cuca, Luis; Delgado, Gabriela

    2016-03-01

    The rational search of novel bioactive molecules against pathogens with immunomodulatory activity is presently one of the most significant approaches to discover and design new therapeutic agents for effective control of infectious diseases, such as the infection caused by Leishmania parasites. In the present study, we evaluated the therapeutic efficacy of the recently characterized immunomodulatory compound 11α,19β-dihydroxy-7-acetoxy-7-deoxoichangin, a seco-limonoid derived from the bark of Raputia heptaphylla (Pittier) using: (1) peritoneal macrophages and (2) Mesocricetus auratus hamsters infected with Leishmania (V.) panamensis and Leishmania (L.) amazonensis. We observed the ability of this seco-limonoid to induce the effective control of the parasite either in vitro [determining an effective concentration 50 (EC50) of 59 µ m at the infection model] and in vivo (inducing clinical improvement or even cure in infected animals treated compared with the groups of animals treated with vehicle solution or meglumine antimoniate).

  17. Membrane phospholipid fatty acid composition regulates cardiac SERCA activity in a hibernator, the Syrian hamster (Mesocricetus auratus.

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    Sylvain Giroud

    Full Text Available Polyunsaturated fatty acids (PUFA have strong effects on hibernation and daily torpor. Increased dietary uptake of PUFA of the n-6 class, particularly of Linoleic acid (LA, C18:2 n-6 lengthens torpor bout duration and enables animals to reach lower body temperatures (T(b and metabolic rates. As previously hypothesized, this well-known influence of PUFA may be mediated via effects of the membrane fatty acid composition on sarcoplasmic reticulum (SR Ca(2+-ATPase 2a (SERCA in the heart of hibernators. We tested the hypotheses that high proportions of n-6 PUFA in general, or specifically high proportions of LA (C18:2 n-6 in SR phospholipids (PL should be associated with increased cardiac SERCA activity, and should allow animals to reach lower minimum T(b in torpor. We measured activity of SERCA from hearts of hibernating and non-hibernating Syrian hamsters (Mesocricetus auratus in vitro at 35 °C. Further, we determined the PL fatty acid composition of the SR membrane of these hearts. We found that SERCA activity strongly increased as the proportion of LA in SR PL increased but was negatively affected by the content of Docosahexaenoic acid (DHA; C22:6 n-3. SR PL from hibernating hamsters were characterized by high proportions of LA and low proportions of DHA. As a result, SERCA activity was significantly higher during entrance into torpor and in torpor compared to inter-bout arousal. Also, animals with increased SERCA activity reached lower T(b during torpor. Interestingly, a subgroup of hamsters which never entered torpor but remained euthermic throughout winter displayed a phenotype similar to animals in summer. This was characterized by lower proportions of LA and increased proportions of DHA in SR membranes, which is apparently incompatible with torpor. We conclude that the PUFA composition of SR membranes affects cardiac function via modulating SERCA activity, and hence determines the minimum T(b tolerated by hibernators.

  18. Evaluation of the Leishmanicidal Activity of Rutaceae and Lauraceae Ethanol Extracts on Golden Syrian Hamster (Mesocricetus auratus) Peritoneal Macrophages.

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    Chávez Enciso, N A; Coy-Barrera, E D; Patiño, O J; Cuca, L E; Delgado, Gabriela

    2014-05-01

    Traditional medicine has provided a number of therapeutic solutions for the control of infectious agents, cancers, and other diseases. After screening a wide variety of Colombian plant extracts, we have identified promising antileishmanial activity in ethanol extracts from Ocotea macrophylla (Lauraceae) and Zanthoxyllum monophyllum (Rutaceae). In this study, we evaluated the in vitro activity of two ethanol extracts, one from Ocotea macrophylla and the other from Zanthoxyllum monophyllum and one alkaloid fraction of ethanol extract of Zanthoxyllum monophyllum, on peritoneal macrophages isolated from golden Syrian hamsters (Mesocricetus auratus) infected with Leishmania panamensis and Leishmania major promastigotes. All of the extracts studied displayed promising (≥2) selectivity indices (S/I), the most significant of which were for ethanol extract of Zanthoxyllum monophyllum against Leishmania panamensis (S/I=12) and alkaloid fraction of ethanol extract of Zanthoxyllum monophyllum against Leishmania major (S/I=11). These results support the use of ethanol extracts and alkaloid fractions isolated from Ocotea macrophylla and Zanthoxyllum monophyllum, respectively; as therapeutic options for cutaneous leishmaniasis.

  19. Perception of scent over-marks by golden hamsters (Mesocricetus auratus): novel mechanisms for determining which individual's mark is on top.

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    Johnston, R E; Bhorade, A

    1998-09-01

    Hamsters preferentially remember or value the top scent of a scent over-mark. What cues do they use to do this? Using habituation-discrimination techniques, we exposed male golden hamsters (Mesocricetus auratus) on 3 to 4 trials to genital over-marks from 2 females and then tested subjects for their familiarity with these 2 scents compared with that of a novel female's secretion. Preferential memory for 1 of the 2 individuals' scents did not occur if the 2 marks did not overlap or did not overlap but differed in age, but it did occur if a region of overlap existed or 1 mark apparently occluded another (but did not overlap it). Thus, hamsters use regions of overlap and the spatial configuration of scents to evaluate over-marks. These phenomena constitute evidence for previously unsuspected perceptual abilities, including olfactory scene analysis, which is analogous to visual and auditory scene analysis.

  20. Adolescent anabolic/androgenic steroids: Aggression and anxiety during exposure predict behavioral responding during withdrawal in Syrian hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Ricci, Lesley A; Morrison, Thomas R; Melloni, Richard H

    2013-11-01

    In the U.S. and worldwide anabolic/androgenic steroid use remains high in the adolescent population. This is concerning given that anabolic/androgenic steroid use is associated with a higher incidence of aggressive behavior during exposure and anxiety during withdrawal. This study uses pubertal Syrian hamsters (Mesocricetus auratus) to investigate the hypothesis that an inverse behavioral relationship exists between anabolic/androgenic steroid-induced aggression and anxiety across adolescent exposure and withdrawal. In the first experiment, we examined aggression and anxiety during adolescent anabolic/androgenic steroid exposure and withdrawal. Adolescent anabolic/androgenic steroid administration produced significant increases in aggression and decreases in anxiety during the exposure period followed by significant decreases in aggression and increases in anxiety during anabolic/androgenic steroid withdrawal. In a second experiment, anabolic/androgenic steroid exposed animals were separated into groups based on their aggressive response during the exposure period and then tested for anxiety during exposure and then for both aggression and anxiety during withdrawal. Data were analyzed using a within-subjects repeated measures predictive analysis. Linear regression analysis revealed that the difference in aggressive responding between the anabolic/androgenic steroid exposure and withdrawal periods was a significant predictor of differences in anxiety for both days of testing. Moreover, the combined data suggest that the decrease in aggressive behavior from exposure to withdrawal predicts an increase in anxiety-like responding within these same animals during this time span. Together these findings indicate that early anabolic/androgenic steroid exposure has potent aggression- and anxiety-eliciting effects and that these behavioral changes occur alongside a predictive relationship that exists between these two behaviors over time. © 2013.

  1. Adolescent Anabolic/Androgenic Steroids: Aggression and Anxiety During Exposure Predict Behavioral Responding During Withdrawal in Syrian Hamsters (Mesocricetus auratus)

    Science.gov (United States)

    Ricci, Lesley A.; Morrison, Thomas R.; Melloni, Richard H.

    2014-01-01

    In the U.S. and worldwide anabolic/androgenic steroid use remains high in the adolescent population. This is concerning given that anabolic/androgenic steroid use is associated with a higher incidence of aggressive behavior during exposure and anxiety during withdrawal. This study uses pubertal Syrian hamsters (Mesocricetus auratus) to investigate the hypothesis that an inverse behavioral relationship exists between anabolic/androgenic steroid-induced aggression and anxiety across adolescent exposure and withdrawal. In the first experiment, we examined aggression and anxiety during adolescent anabolic/androgenic steroid exposure and withdrawal. Adolescent anabolic/androgenic steroid administration produced significant increases in aggression and decreases in anxiety during the exposure period followed by significant decreases in aggression and increases in anxiety during anabolic/androgenic steroid withdrawal. In a second experiment, anabolic/androgenic steroid exposed animals were separated into groups based on their aggressive response during the exposure period and then tested for anxiety during exposure and then for both aggression and anxiety during withdrawal. Data were analyzed using a within subjects repeated measures predictive analysis. Linear regression analysis revealed that the difference in aggressive responding between the anabolic/androgenic steroid exposure and withdrawal periods was a significant predictor of differences in anxiety for both days of testing. Moreover, the combined data suggest that the decrease in aggressive behavior from exposure to withdrawal predicts an increase in anxiety-like responding within these same animals during this time span. Together these findings indicate that early anabolic/androgenic steroid exposure has potent aggression- and anxiety- eliciting effects and that these behavioral changes occur alongside a predictive relationship that exists between these two behaviors over time. PMID:24126136

  2. Quantification of fecal estradiol and progesterone metabolites in Syrian hamsters (Mesocricetus auratus

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    Chelini M.O.M.

    2005-01-01

    Full Text Available Alternative methods to the utilization of laboratory animal blood and its by-products are particularly attractive, especially regarding hamsters due to their small size and difficulties in obtaining serial blood samples. Steroid hormone metabolite quantification in feces, widely used in studies of free-ranging or intractable animals, is a non-invasive, non-stressor, economical, and animal saving technique which allows longitudinal studies by permitting frequent sampling of the same individual. The present study was undertaken to determine the suitability of this method for laboratory animals. Estradiol and progesterone metabolites were quantified by radioimmunoassay in feces of intact, sexually mature female Syrian hamsters during the estrous cycle (control and in feces of superovulated females. Metabolites were extracted by fecal dilution in ethanol and quantified by solid phase radioimmunoassay. Median estrogen and progesterone concentrations were 9.703 and 180.74 ng/g feces in the control group, respectively. Peaks of estrogen (22.44 ± 4.54 ng/g feces and progesterone (655.95 ± 129.93 ng/g feces mean fecal concentrations respectively occurred 12 h before and immediately after ovulation, which is easily detected in this species by observation of a characteristic vaginal postovulatory discharge. Median estrogen and progesterone concentrations (28.159 and 586.57 ng/g feces, respectively were significantly higher in superovulated animal feces (P < 0.0001. The present study demonstrated that it is possible to monitor ovarian activity in Syrian hamsters non-invasively by measuring fecal estradiol and progesterone metabolites. This technique appears to be a quite encouraging method for the development of new endocrinologic studies on laboratory animals.

  3. Neural mechanisms of individual and sexual recognition in Syrian hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Petrulis, Aras

    2009-06-25

    Recognizing the individual and sexual identities of conspecifics is critical for adaptive social behavior and, in most mammals this information is communicated primarily by chemosensory cues. Due to its heavy reliance on odor cues, we have used the Syrian hamster as our model species for investigating the neural regulation of social recognition. Using lesion, electrophysiological and immunocytochemical techniques, separate neural pathways underlying recognition of individual odors and guidance of sex-typical responses to opposite-sex odors have been identified in both male and female hamsters. Specifically, we have found that recognition of individual odor identity requires olfactory bulb connections to entorhinal cortex (ENT) rather than other chemoreceptive brain regions. This kind of social memory does not appear to require the hippocampus and may, instead, depend on ENT connections with piriform cortex. In contrast, sexual recognition, through either differential investigation or scent marking toward opposite-sex odors, depends on both olfactory and vomeronasal system input to the corticomedial amygdala. Preference for investigating opposite-sex odors requires primarily olfactory input to the medial amygdala (ME) whereas appropriately targeted scent marking responses require vomeronasal input to ME as well as to other structures. Within the ME, the anterior section (MEa) appears important for evaluating or classifying social odors whereas the posterodorsal region (MEpd) may be more involved in generating approach to social odors. Evidence is presented that analysis of social odors may initially be done in MEa and then communicated to MEpd, perhaps through micro-circuits that separately process male and female odors.

  4. Foraging Behavior in Golden Hamsters (Mesocricetus Auratus: Effect of the Distance among Multiple Patches

    Directory of Open Access Journals (Sweden)

    Felipe Cabrera

    2008-05-01

    Full Text Available The pattern of travel and the efficiency in foraging behavior was evaluated in four hamsters searching for food within an enclosure with multiple patches. Two different distances among patches were randomly arranged: Near-Patches (10 cm separation and Distant-Patches (21.5 cm separation. Subjects obtained the food by mounting over the cylinders (stations placed in the enclosure of 110 cm2. Results showed that in both, Near and Distant conditions, the distance between responses was longer in late stages of the trials then in early stages. Nonetheless, the most choices to adjacent stations were in Distant-Patches condition, while skips and diagonal-station choices were more frequently showed in the Near-Patches condition.

  5. Integração do enxerto heterólogo de pele humana no subepitélio da bolsa jugal do hamster (Mesocricetus auratus Integration of human skin heterologous graft into hamster (Mesocricetus auratus cheek pouch sub-epithelium

    Directory of Open Access Journals (Sweden)

    Bernardo Hochman

    2003-10-01

    Full Text Available OBJETIVO: Descrever a integração de enxertos de pele total humana no subepitélio da bolsa jugal do hamster (Mesocricetus auratus. MÉTODOS: A amostragem consistiu de 18 hamsters machos, exogâmicos, com 10 a 14 semanas de idade. Fragmentos de pele humana normal foram obtidos de pele excedente de mastoplastia redutora de paciente parda. Cada hamster foi enxertado em ambas as bolsas com fragmentos de pele, perfazendo um total de 36 fragmentos enxertados. Os animais foram distribuídos, em 6 grupos, para exame dos fragmentos enxertados com 5, 12, 21, 42, 84 e 168 dias. Uma avaliação macroscópica foi realizada comparando a bolsa contendo o fragmento enxertado em cada período com a mesma bolsa no pós-operatório imediato, mediante fotografias padronizadas. Na avaliação microscópica foi adotado como critério de integração a presença de vasos sangüíneos na derme dos enxertos. Observou-se também a presença de queratina, melanócitos, infiltrado celular e aspecto do tecido conjuntivo. RESULTADOS: Na avaliação macroscópica foi observada uma reação vascular em torno dos fragmentos até 12 dias do implante, e a presença de pigmentação castanho-escura a partir de 42 dias. À microscopia, integraram-se 80,64% dos fragmentos enxertados, inclusive no grupo de 168 dias. Observou-se infiltrado celular inflamatório até 12 dias, a presença de melanócitos a partir de 42 dias e uma hialinização do tecido conjuntivo após 84 dias. CONCLUSÕES: Fragmentos de pele humana integram-se no tecido celular subcutâneo da bolsa jugal do hamster, mantêm-se vascularizados por 168 dias, e conservam o epitélio íntegro até 21 dias. O subepitélio da bolsa representa modelo experimental de investigação da fisiologia de pele humana ex vivo.PURPOSE: To describe the integration of total human skin into hamster (Mesocricetus auratus cheek pouch. METHODS: The sample was formed by 18 male hamsters, outbred, aging between 10 and 14 weeks. Fragments of

  6. Syrian hamsters (Mesocricetus auratus) with simultaneous intestinal Giardia sp., Spironucleus sp., and trichomonad infections.

    Science.gov (United States)

    Sheppard, Barbara J; Stockdale Walden, Heather D; Kondo, Hirotaka

    2013-11-01

    A commercial facility producing hamsters with a history of infection by dwarf tapeworm (Hymenolepis nana) submitted 15 animals for necropsy and postmortem parasitological and microscopic examination. No tapeworms were detected grossly or microscopically. Fecal examination including gastrointestinal mucosal smears demonstrated mixed intestinal bacteria and low numbers of Giardia sp. Histologic examination of small intestine demonstrated filling of the small intestinal crypts by large numbers of 7-9 µm × 3 µm, rod to crescent or teardrop-shaped flagellates consistent with Spironucleus sp. These organisms had two 1-µm, basophilic, oval nuclei and multiple superficial flagella-like structures. Much larger 10-15 µm × 8-10 µm, oval to pear-shaped organisms were also present in lower numbers and usually located with the crypts. These larger flagellates had multiple flagella and a basophilic rod-shaped nucleus. The larger flagellates included Giardia sp., which had an intimate interface with the surface of the mucosal epithelium, bilaterally symmetry, and binucleation. Lower numbers of trichomonads were also present and were distinguished by an undulating surface membrane and a single nucleus. The mucosa was hyperplastic and moderately inflamed. Although the tapeworm infection was resolved, diagnosis of multiple intestinal flagellates by fecal examination is complicated by the varying sensitivity and diagnostic accuracy of different types of fecal analysis for different flagellate types. Key differences in the morphology and location of the different types of flagellates as observed by histology of intestinal tissues provide important additional diagnostic information to distinguish trichomonads, Spironucleus sp., and Giardia sp.

  7. Histochemical study of brown-fat cells in the golden hamster (Mesocricetus auratus) in cultures

    International Nuclear Information System (INIS)

    Sokolov, V.E.; Boyadzhieva-Mikhailova, A.; Koncheva, L.; Angelova, P.; Evgen'eva, T.P.

    1985-01-01

    The authors undertake the task of studying the synthesis of certain hormones by brown-fat cells. The authors used brown-fat cells from the golden hamster. The metabolism of brown-fat cells was studied on precultured cells, which made it possible to detect the synthesis of the studied substances rather than their accumulation in the organ. The authors conducted three experiments. First, fragments of brown fat were cultivated in diffusion chambers in vivo. Pieces of brown fat were cultivated in parallel in vitro on agar (organotypic cultures) and on plasma (histotypic cultures). During cultivation in diffusion chambers, the chambers were implanted in the abdominal cavity of young white rats. For in vitro cultivation, TCM 199 plus 15-20% calf serum was used. A total of 36 cultures with 12 cultures in each series of experiments were performed. The auto-radiographic studies of brown-fat cells were conducted on 24-hour cultures and on brown-fat fragments taken from the intact animal. The cultures were incubated with isotopes for 1 h. Either [ 3 H]lysine (87.3 Ci/mM specific activity), [ 3 H]arginine (16.7 Ci/mM), [ 3 H]glycerol (43 Ci/mM), or [ 3 H]cholesterol (43 Ci/mM) were added to the medium. After incubation, the cultures were washed three times in pure medium, fixed in Sierra fluid, and embedded in paraffin. The paraffin sections were covered with Ilford K 2 emulsion, and the preparations were exposed for 20 days at 4 0 C temperature. Radio-immunological methods were used to study the accumulation of estradiol-17-beta in the culture medium by the Dobson method and that of testerone. The culture medium was taken on cultivation days 2,4,6,8, and 10. The medium was changed during cultivation every third day, which made it possible to judge the rates of accumulation of material with increase in the cultivation times

  8. Development of the leptospirosis by experimental infection in hamsters (Mesocricetus auratus with Leptospira interrogans serovar Canicola, strain LO4, by intact and scratched skin exposures

    Directory of Open Access Journals (Sweden)

    Carolina de Sousa Américo Batista

    2010-10-01

    Full Text Available The establishment and evolution of leptospirosis in hamster (Mesocricetus auratus by experimental infection with Leptospira interrogans serovar Canicola, LO4 strain, by intact and scratched skin exposures, having as control the intraperitoneal route, were evaluated. Hundred-twenty female hamsters distributed in two groups according to inoculation route (intact and scratched skin were used. Infectious inoculum was constituted by a pure culture of L. interrogans serovar Canicola (strain LO4, isolated from liver from a slaughtered swine in Londrina, Paraná state and typified by agglutinins adsortion technique with monoclonal antibody kit at the Royal Tropical Institute, Amsterdam, the Netherlands. The animals were observed twice a day during 21 days. Animals that died were necropsied and kidneys, liver, genital tract (uterus and ovaries and brain were aseptically collected. On the 21st post-inoculation day, surviving animals were euthanized. In these animals, serum samples were also collected by cardiac puncture to antileptospires agglutinins research using microscopic agglutination test (MAT. Fresh direct microscopy and microbiological culture were used for the detection of leptospires. Scratched skin route induced larger lethality when compared to intact skin route, with establishment and evolution of leptospirosis. On the other hand, intact skin route induced renal and/or genital carrier state more frequently. LO4 strain presented low immunogenic power, characterized by soroconversion at the MAT in only one inoculated animal.

  9. Social housing and social isolation: Impact on stress indices and energy balance in male and female Syrian hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Ross, Amy P; Norvelle, Alisa; Choi, Dennis C; Walton, James C; Albers, H Elliott; Huhman, Kim L

    2017-08-01

    Although Syrian hamsters are thought to be naturally solitary, recent evidence from our laboratory demonstrates that hamsters may actually prefer social contact. Hamsters increase their preference for a location associated with an agonistic encounter regardless of whether they have "won" or "lost". It has also been reported that social housing as well as exposure to intermittent social defeat or to a brief footshock stressor increase food intake and body mass in hamsters. By contrast, it has also been suggested that housing hamsters in social isolation causes anxiety-induced anorexia and reductions in body mass selectively in females. The purpose of this study was to determine the physiological consequences of housing hamsters in social isolation versus in social groups. Male and female hamsters were housed singly or in stable groups of 5 for 4weeks after which they were weighed and trunk blood was collected. In addition, fat pads and thymus and adrenal glands were extracted and weighed. Serum and fecal cortisol were measured using an enzyme-linked immunoassay. Housing condition had no effect on serum or fecal cortisol, but socially housed hamsters displayed modest thymus gland involution. Socially housed females weighed more than did any other group, and socially housed females and males had more fat than did socially isolated hamsters. No wounding or tissue damage occurred in grouped hamsters. Overall, these data suggest that Syrian hamsters tolerate both stable social housing and social isolation in the laboratory although social housing is associated with some alteration in stress-related and bioenergetic measures. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. After infection with Leishmania infantum, Golden Hamsters (Mesocricetus auratus) become more attractive to female sand flies (Lutzomyia longipalpis).

    Science.gov (United States)

    Nevatte, T M; Ward, R D; Sedda, L; Hamilton, J G C

    2017-07-21

    In Brazil, human and canine visceral leishmaniasis is caused by infection with Leishmania infantum, a Protist parasite transmitted by blood-feeding female Lutzomyia longipalpis sand flies. The objective of this study was to determine if the odour of hamsters, infected with Le. infantum, was more attractive than the odour of the same hamsters, before they were infected. The attractiveness of odour collected from individual hamsters (n = 13), before they were infected, was compared in a longitudinal study, with the attractiveness of the odour of the same hamster in a Y-tube olfactometer bioassay, at a late stage of infection. The odour of six of the golden hamsters was significantly more attractive to 50% of the female sand flies at the end of infection compared to before infection and the odour of four of the golden hamsters was significantly more attractive to 75% of the female sand flies at the end of infection. These results strongly indicate that hamsters infected with Le. infantum become significantly more attractive to a greater proportion of female sand flies as the infection progresses.

  11. Yellow fever virus isolated from a fatal post vaccination event: an experimental comparative study with the 17DD vaccine strain in the Syrian hamster (Mesocricetus auratus

    Directory of Open Access Journals (Sweden)

    Sueli Guerreiro Rodrigues

    2004-01-01

    Full Text Available In order to investigate the pathogenicity of the virus strain GOI 4191 that was isolated from a fatal adverse event after yellow fever virus (YFV vaccination, an experimental assay using hamsters (Mesocricetus auratus as animal model and YFV 17DD vaccine strain as virus reference was accomplished. The two virus strains were inoculated by intracerebral, intrahepatic and subcutaneous routes. The levels of viremia, antibody response, and aminotransferases were determined in sera; while virus, antigen and histopathological changes were determined in the viscera. No viremia was detected for either strain following infection; the immune response was demonstrated to be more effective to strain GOI 4191; and no significant aminotransferase levels alterations were detected. Strain GOI 4191 was recovered only from the brain of animals inoculated by the IC route. Viral antigens were detected in liver and brain by immunohistochemical assay. Histothological changes in the viscera were characterized by inflammatory infiltrate, hepatocellular necrosis, and viral encephalitis. Histological alterations and detection of viral antigen were observed in the liver of animals inoculated by the intrahepatic route. These findings were similar for both strains used in the experiment; however, significant differences were observed from those results previously reported for wild type YFV strains.

  12. Gonadotropin-inhibitory hormone reduces sexual motivation but not lordosis behavior in female Syrian hamsters (Mesocricetus auratus)

    DEFF Research Database (Denmark)

    Piekarski, David J; Zhao, Sheng; Jennings, Kimberly J

    2013-01-01

    these neuropeptides serve as neuromodulators to coordinate female sexual behavior with the limited window of fertility has not been thoroughly explored. In the present study, either intact or ovariectomized, hormone-treated female hamsters were implanted for fifteen days with chronic release osmotic pumps filled...

  13. The effects of day length, hibernation, and ambient temperature on incisor dentin in the Turkish hamster (Mesocricetus brandti).

    Science.gov (United States)

    Batavia, Mariska; Nguyen, George; Zucker, Irving

    2013-05-01

    Dentin is deposited on a circadian basis, and daily layers manifest as bands on the medial surfaces of rodent incisors. Hibernation alters dentin deposition, and a distinct hibernation mark has been described on incisor surfaces of several rodent species; the factors that influence the morphology of this mark are poorly understood. We tested the effects of day length, torpor expression, and ambient temperature on incisor surface morphology in Turkish hamsters housed in one of four conditions: long days (LDs) at 22 °C, short days (SDs) at 22 °C, SDs at 5 °C, and SDs at 13 °C. Body temperature was monitored continuously with implanted radio transmitters, and teeth examined postmortem. Teeth of SD hamsters had narrower, less distinct circadian increments than those of LD hamsters, but the width of ultradian increments was similar in both photoperiods. Hibernation at both 5 and 13 °C was associated in most specimens with very narrow, sharply defined dentin increments and increased tooth heterogeneity. Hamsters in SDs at 5 °C that did not hibernate lacked characteristic hibernation increments. At 5 °C, but not 13 °C, the number and cumulative width of hibernation increments were related to number and cumulative duration of periodic arousals. Our results suggest that incremental deposition of dentin in rodent incisors may be a useful trait for characterizing hibernation behavior in both evolutionary and historical contexts.

  14. Photoperiodic modulation of thyroid hormone receptor (TR-α), deiodinase-2 (Dio-2) and glucose transporters (GLUT 1 and GLUT 4) expression in testis of adult golden hamster, Mesocricetus auratus.

    Science.gov (United States)

    Verma, Rakesh; Haldar, Chandana

    2016-12-01

    Phenomenon of seasonal reproduction is being regulated by changes in day length or photoperiod. The molecular mechanism underlying the event of photoperiodic regulation of testis and thyroid functions along with glucose uptake transporters has never been reported for golden hamster, M. auratus. The present study was performed to investigate the effect of photoperiod on the expression of key thyroid hormone receptor (TR-α), deiodinase-2 (Dio-2) and glucose uptake transporters (GLUT-1 & GLUT-4) in testicular germ cell and Leydig cells, and its correlation with the testicular androgen receptor (AR), germ cell proliferation factor (PCNA) and cell survival factor (Bcl-2) in testis of adult golden hamster, Mesocricetus auratus. Hamsters were exposed to different photoperiodic regimes i.e. critical photoperiod (CP), short day (SD) and long day (LD) for 10weeks. LD induces upregulation of thyroidal and gonadal activity as evident by active thyroid gland and testicular histoarchitecture, peripheral total thyroid (tT3, tT4) and testosterone hormone profiles when compared with SD exposed hamsters. Further, LD increased the expression of testicular TR-α, Dio-2, GLUT-1, GLUT-4 along with testicular AR and glucose content thereby enhancing germ cell proliferation and survival as reflected by increased PCNA and Bcl-2 expression when compared to SD exposed hamsters. Thus, it can be suggested that testicular thyroid hormone status is being regulated by photoperiod and is possibly involved in seasonal adaptation to reproductive phenomenon of golden hamster. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Altered microRNA expression patterns during the initiation and promotion stages of neonatal diethylstilbestrol-induced dysplasia/neoplasia in the hamster (Mesocricetus auratus) uterus.

    Science.gov (United States)

    Padmanabhan, Ramesh; Hendry, Isabel R; Knapp, Jennifer R; Shuai, Bin; Hendry, William J

    2017-10-01

    Treatment of Syrian hamsters on the day of birth with the prototypical endocrine disruptor and synthetic estrogen, diethylstilbestrol (DES), leads to 100% occurrence of uterine hyperplasia/dysplasia in adulthood, a large proportion of which progress to neoplasia (endometrial adenocarcinoma). Consistent with our prior gene expression analyses at the mRNA and protein levels, we now report (based on microarray, real-time polymerase chain reaction, and in situ hybridization analyses) that progression of the neonatal DES-induced dysplasia/neoplasia phenomenon in the hamster uterus also includes a spectrum of microRNA expression alterations (at both the whole-organ and cell-specific level) that differ during the initiation (upregulated miR-21, 200a, 200b, 200c, 29a, 29b, 429, 141; downregulated miR-181a) and promotion (downregulated miR-133a) stages of the phenomenon. The biological processes targeted by those differentially expressed miRNAs include pathways in cancer and adherens junction, plus regulation of the cell cycle, apoptosis, and miRNA functions, all of which are consistent with our model system phenotype. These findings underscore the need for continued efforts to identify and assess both the classical genetic and the more recently recognized epigenetic mechanisms that truly drive this and other endocrine disruption phenomena.

  16. The autoradiographic pattern of DNA synthesis in Papova virus- and N-methyl-N-nitroso urea induced skin tumors of the Syrian hamster (Mesocricetus auratus)

    International Nuclear Information System (INIS)

    Amlacher, E.; Bierwolf, D.

    1977-01-01

    In skin tumors induced in Syrian hamsters by Papova viruses or produced chemically by dripping of methylnitroso urea (MNU) the pattern of DNA synthesis was studied in vitro and in vivo by autoradiography. The greater part of DNA synthesis in the Papova tumor of the hamster is of cellular origin. Only the cells localized adjacent to keratinizing regions of the tumors may be considered as virus-infected with progressive multiplication of viruses. This also applies to all nuclei with cellular DNA synthesis only in the marginal chromatin. Moreover viral DNA synthesis is supposed in the cytoplasm, too. In methylnitroso urea-induced squamous cell carcinoma labelled cells were likewise found adjacent to keratinizing tumor regions and the pattern of DNA synthesis is generally not limited to the ''stratum basale''. With increasing malignancy the pattern of DNA synthesis is changing also in chemically induced tumors and is no longer limited to the stratum basale where it still can be demonstrated in the papilloma. (author)

  17. Presence of amastigotes in the central nervous system of hamsters infected with Leishmania sp. Presença de amastigotas em sistema nervoso central de hamster infectado com Leishmania sp.

    Directory of Open Access Journals (Sweden)

    Elisangela de Oliveira

    2011-06-01

    Full Text Available Visceral leishmaniasis (VL is a severe chronic disease caused by Leishmania (Leishmania infantum chagasi. Better knowledge on the effects caused by this disease can help develop adequate clinical management and treatment. Parasitological and immunohistochemical studies were performed golden hamsters Mesocricetus auratus infected with bone marrow from individuals with VL in the State of Mato Grosso do Sul, central-west Brazil. The effects of parasitism in the spleen, liver, kidneys, lungs, heart and brain of the animals were examined. Eighteen hamsters were inoculated intraperitoneally, and six healthy animals were used as negative controls. The animals were kept in the animal house and checked for clinical signs. Specimens of each organ were examined for the presence of amastigotes. Immunohistochemical technique was performed in all brain specimens and organs negative on the direct examination of parasites. Direct examination of amastigotes was positive in the spleen and liver of all infected animals; 33.3% showed the parasite in the kidneys and lungs, and 16.7% in the heart. Parasitic forms were seen in 83.3% (15/18 of the brain examined. Immunohistochemistry confirmed the results of the direct examination, except in two specimens of lung tissue and in the brain specimens. Other studies are needed to further clarify the effect of the parasite in the central nervous system.A leishmaniose visceral (LV é uma doença crônica grave, causada pelo parasito Leishmania (Leishmania infantum chagasi. Esclarecer as alterações provocadas pela doença é fundamental para que se adotem condutas clínicas e de tratamento adequadas. Com o objetivo de analisar a infecção experimental em hamsters da linhagem golden, Mesocricetus auratus, infectados com tecido de medula óssea de pacientes com LV no Estado de Mato Grosso do Sul, foram realizados estudos parasitológicos e de imunomarcação. Foi verificada a distribuição do parasitismo no baço, f

  18. Oxytocin (OT) and arginine-vasopressin (AVP) act on OT receptors and not AVP V1a receptors to enhance social recognition in adult Syrian hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Song, Zhimin; Larkin, Tony E; Malley, Maureen O'; Albers, H Elliott

    2016-05-01

    Social recognition is a fundamental requirement for all forms of social relationships. A majority of studies investigating the neural mechanisms underlying social recognition in rodents have investigated relatively neutral social stimuli such as juveniles or ovariectomized females over short time intervals (e.g., 2h). The present study developed a new testing model to study social recognition among adult males using a potent social stimulus. Flank gland odors are used extensively in social communication in Syrian hamsters and convey important information such as dominance status. We found that the recognition of flank gland odors after a 3min exposure lasted for at least 24h, substantially longer than the recognition of other social cues in rats and mice. Intracerebroventricular injections of OT and AVP prolonged the recognition of flank gland odor for up to 48h. Selective OTR but not V1aR agonists, mimicked these enhancing effects of OT and AVP. Similarly, selective OTR but not V1aR antagonists blocked recognition of the odors after 20min. In contrast, the recognition of non-social stimuli was not blocked by either the OTR or the V1aR antagonists. Our findings suggest both OT and AVP enhance social recognition via acting on OTRs and not V1aRs and that the recognition enhancing effects of OT and AVP are limited to social stimuli. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Vasopressin immunoreactivity and release in the suprachiasmatic nucleus of wild-type and tau mutant Syrian hamsters

    NARCIS (Netherlands)

    Van der Zee, EA; Oklejewicz, M; Jansen, K; Daan, S; Gerkema, MP

    2002-01-01

    Despite the prominent role of the Syrian hamster (Mesocricetus auratus) in studies of circadian rhythms, there are no data available on the temporal dynamics of the neuropeptide vasopressin (AVP), a major output system of the suprachiasmatic nucleus (SCN). We studied the hamster SCN-AVP system in

  20. Determination of elements in blood of golden hamster by NAA; Determinacao de elementos em sangue de hamster dourado usando AAN

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Rodrigo Oliveira de

    2009-07-01

    In the present study Neutron Activation Analysis technique has been used to determine, simultaneously, some element concentrations of clinical relevance in whole blood samples of golden hamster. The normal range for Br, Ca, Cl K, Mg, Na and S considering 2 {sigma} (Two Standard deviations) was 0.011 0.047 gL{sup -1} (Br); 0.11 0.35 gL{sup -1} (Ca); 2.11 3.75 gL{sup -1} (Cl); 1.35 2.79 gL{sup -1} (K), 0.026 0.090 gL{sup -1} (Mg), 1.03 2.51 gL{sup -1} (Na) e 0.97 2.01 gL{sup -1} (S). The knowledge of these limits became possible to perform clinical investigation in this animal model using whole blood. The comparison with the results from human being whole blood estimation (Hamster and human) became possible to check the similarities or physiologic differences, an important data for animal experimentation. (author)

  1. Metabolic rate changes proportionally to circadian frequency in tau mutant Syrian hamsters

    NARCIS (Netherlands)

    Oklejewicz, M; Hut, RA; Daan, S; Loudon, ASI; Stirland, AJ; Loudon, Andrew S.I.; Stirland, Anne J.

    1997-01-01

    The tau mutation in Syrian hamsters (Mesocricetus auratus) is phenotypically expressed in a period of the circadian rhythm of about 20 h in homozygotes (SS) and about 22 h in heterozygotes (S+). The authors investigate whether this well-defined model for variation in circadian period exhibits

  2. Development of Chronic and Acute Golden Syrian Hamster Infection Models with Leptospira borgpetersenii serovar Hardjo

    Science.gov (United States)

    The golden Syrian hamster (Mesocricetus auratus) is frequently used as a model to study virulence for several species of Leptospira. Onset of an acute, lethal infection following infection with several pathogenic Leptospira species has been widely adopted for vaccine testing. An important exceptio...

  3. Efeitos do reiki na evolução do granuloma induzido através da inoculação do BCG em hamsters e do tumor ascítico de Ehrlich induzido em camundongos

    OpenAIRE

    Ricardo Rodrigues Garé

    2008-01-01

    Estudaram-se os efeitos da influência do Reiki na evolução do granuloma induzido experimentalmente pela inoculação do BCG no coxim plantar de hamsters, assim como os efeitos da mesma terapia em camundongos portadores do tumor ascítico de Ehrlich in vivo e in vitro. No modelo de inflamação granulomatosa crônica, utilizou-se 40 hamsters machos, os quais após serem inoculados com BCG no dia 0 no coxim da pata posterior direita, foram separados em dois grupos contendo 20 animais em cada. Um grupo...

  4. Antileishmanial activity of licochalcone A in mice infected with <em>Leishmania majorem> and in hamsters infected with <em>Leishmania donovaniem>

    DEFF Research Database (Denmark)

    Chen, M; Christensen, S B; Theander, T G

    1994-01-01

    This study was designed to examine the antileishmanial activity of the oxygenated chalcone licochalcone A in mice and hamsters infected with Leishmania parasites. Intraperitoneal administration of licochalcone A at doses of 2.5 and 5 mg/kg of body weight per day completely prevented lesion develo...

  5. Perfil lipídico, defesas antioxidantes e marcadores de função hepática e renal em hamsteres tratados com extratos de sementes de urucum

    OpenAIRE

    Rossoni Júnior, Joamyr Victor

    2008-01-01

    O urucum (Bixa orellana L.) tem sido descrito pela comunidade científica por seu efeito hipocolesterolemiante. Dessa forma o objetivo desse trabalho foi avaliar o efeito da infusão aquosa do urucum (Bixa orellana L) e da torta de bixina sobre o perfil lipídico, defesas antioxidantes e marcadores de função hepática e renal em hamsteres. Foram utilizados 64 hamsteres machos Golden Syrian que foram distribuídos em oito grupos: controle (C) recebeu dieta padrão (AIN-93 M), H recebeu dieta hiperco...

  6. [Investigation on the prevalence of gastrointestinal parasites in pet hamsters].

    Science.gov (United States)

    Lv, Chao-Chao; Feng, Chao; Qi, Meng; Yang, Hong-Yu; Jian, Fu-Chun; Ning, Chang-Shen; Zhang, Long-Xian

    2009-06-01

    One hundred and fifty-three fecal samples of pet hamsters (Mesocricetus auratus, Phodopus sungorus, P. campbelli and P. roborovskii) were collected from a pet-market in Zhengzhou, and examined by Sheather's sugar flotation, modified acid-fast staining and Lugol's iodine-solution staining. The prevalence of parasites was 70.7% (41/58), 96.7% (59/61), 83.9% (26/31), and 100% (3/3) respectively, with an overall prevalence of 84.3%. Eggs, cysts or oocysts of Cryptosporidium sp. (15.0%), Giardia sp. (22.2%), coccidian (2.0%), Hymenolepis nana (31.4%), Hymenolepis diminuta (25.5%), Syphacia spp. (41.8%), Aspiculuris tetraptera (7.2%) and undetermined Trichurata nematode (18.3%) were found from the samples. The results suggest that pet hamsters may be infected and transmit several zoonotic parasites.

  7. Social context modulates food hoarding in Syrian hamsters

    Directory of Open Access Journals (Sweden)

    Bibiana Montoya

    2016-09-01

    Full Text Available The effect of the presence of a con-specific in the temporal organization of food hoarding was studied in two varieties of Syrian hamster (Mesocricetus auratus: golden and long-haired. Four male hamsters of each variety were used. Their foraging behavior was observed during four individual and four shared trials in which animals were not competing for the same food source or territory. During individual trials, long-haired hamsters consumed food items directly from the food source, transporting and hoarding only remaining pieces. During shared trials, the long-haired variety hoarded food items before consumption, and increased the duration of hoarding trips, food handling in the storage, and cache size. Golden hamsters maintained the same temporal organization of hoarding behavior (i.e., hoarding food items before consumption throughout both individual and shared trials. However, the golden variety increased handling time at the food source and decreased the duration of hoarding trips, the latency of hoarding and storing size throughout the shared trials. In Syrian hamsters, the presence of a con-specific may signal high probability of food source depletion suggesting that social pressures over food availability might facilitate hoarding behavior. Further studies are required to evaluate cost-benefit balance of food hoarding and the role of cache pilferage in this species.

  8. Equine herpesvirus type 1 induces both neurological and respiratory disease in Syrian hamsters.

    Science.gov (United States)

    Mesquita, Leonardo Pereira; Arévalo, Andressa Ferrari; Zanatto, Dennis A; Miyashiro, Samantha Ive; Cunha, Elenice Maria Sequetin; de Souza, Maria do Carmo Custódio; Villalobos, Eliana Monteforte Cassaro; Mori, Cláudia Madalena Cabrera; Maiorka, Paulo César; Mori, Enio

    2017-05-01

    The equine herpesvirus type 1 (EHV-1) is an important cause of myeloencephalopathy and respiratory disease in horses. Animal models for EHV-1 infection have been specially developed using mice and Syrian hamsters (Mesocricetus auratus). However, few studies have attempted to evaluate the pathogenesis of EHV-1 infection in the central nervous system (CNS) and respiratory system of hamsters. Therefore, the aim of this study was to evaluate the pathogenesis of four Brazilian EHV-1 strains within the CNS and lungs of Syrian hamsters. Hamsters intranasally infected with A4/72, A9/92, A3/97, and Iso/72 EHV-1 strains developed severe neurological and respiratory signs and died during acute EHV-1 infection within 3 to 5days post-inoculation. However, neurological signs were more severe in A4/72 and A9/92-infected hamsters, whereas respiratory signs were more prominent in A3/97 and Iso/72-infected hamsters. In the latter, lesions in the CNS were predominantly inflammatory, whereas in A4/72 and A9/92-infected hamsters, neuronal and liquefactive necrosis were the predominant lesions. EHV-1 infected hamsters also developed an interstitial pneumonia with infiltration of alveolar septa by macrophages, neutrophils, and lymphocytes, with the exception of A9/92-infected hamsters, which developed severe hemorrhages within the airways. EHV-1 antigens were detected along with CNS and pulmonary lesions. EHV-1 was also recovered from CNS of all infected hamsters, whereas the virus was recovered from the lungs of A4/72, A9/92, and Iso/72-infected hamsters. Brazilian EHV-1 strains caused both severe CNS and respiratory disease in hamsters, thus making this species an interesting model for EHV-1 infection in the CNS and respiratory system. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Androgenic Regulation of Male Sexual Behavior and Physiology in the Syrian Hamster (Mesocricetus Auratus)

    OpenAIRE

    Piekarski, David John

    2012-01-01

    The androgen testosterone (T) and its metabolite, dihydrotestosterone (DHT), are released from the gonads and act in the brain and periphery to control many male-typical traits, including male sexual behavior (MSB). The classical model of androgenic action asserts that T, or DHT binds to a single species of intracellular androgen receptor (AR), that acts as a transcription factor to induce transactivation of androgen-regulated genes. Accordingly, androgens may take hours or days to assert t...

  10. Morphogenesis of palatal ridges in the golden hamster (Mesocricetus auratus, Rodentia)

    Czech Academy of Sciences Publication Activity Database

    Buchtová, M.; Matulová, Petra; Witter, K.; Tichý, F.

    2005-01-01

    Roč. 74, č. 3 (2005), s. 319-327 ISSN 0001-7213 R&D Projects: GA MŠk OC B23.001 Institutional research plan: CEZ:AV0Z50450515 Keywords : oral cavity Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.353, year: 2005

  11. Detecção de lesões neoplásicas induzidas em mucosa oral de hamster utilizando espectroscopia de fluorescência Detection of induced neoplastic lesions in the oral mucosa of hamsters using fluorescence spectroscopy

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    Landulfo Silveira Junior

    2004-09-01

    Full Text Available OBJETIVO: Este trabalho teve por objetivo a utilização da técnica de espectroscopia de fluorescência induzida por laser para a caracterização de tecido normal e neoplásico em mucosa jugal de hamster, visando diagnosticar tecidos neoplásicos in vivo. MÉTODOS: O carcinógeno DMBA foi aplicado na bochecha direita de 31 hamsters com 150 ± 10g, três vezes por semana durante 12 semanas. Um animal foi mantido como controle (sem aplicação da droga. Após este período, os animais foram submetidos à espectroscopia de fluorescência induzida por laser de argônio (488nm, acoplado a um cabo de fibras ópticas. A autofluorescência do tecido foi guiada pelo cabo de fibras e analisada por um espectrógrafo e uma câmera CCD 1024X256 pixels, cobrindo a faixa espectral de 550nm a 700nm. Os espectros foram coletados na área da lesão induzida e na bochecha contralateral (normal de todos os animais, além do animal de controle. Subseqüente à espectroscopia, foi realizada a biópsia da lesão para a análise histopatológica. Dois algoritmos de diagnóstico dos espectros de tecido neoplásico, baseados na razão entre regiões espectrais e na técnica de análise das componentes principais (PCA foram implementados. RESULTADOS: Foi demonstrada a existência de um pico intenso na região de 630nm nos tecidos neoplásicos (atribuído à protoporfirina IX, quando comparados com o tecido normal. O algoritmo baseado na razão entre regiões espectrais obteve 100% de sensibilidade e especificidade. O algoritmo baseado na PCA obteve 94% e 100% de sensibilidade e especificidade, respectivamente. CONCLUSÕES: Este trabalho indica que a autofluorescência de tecidos da mucosa oral poderá ser utilizada como uma técnica não-invasiva de diagnóstico, com alta sensibilidade e especificidade.OBJECTIVE: This work analyzes use of the Laser Induced Fluorescence Spectroscopy technique for characterization of normal and neoplastic tissue in the oral mucosa of

  12. Prevention of Clostridium difficile infection in hamsters using a non-toxigenic strain

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    Carlos Augusto de Oliveira Júnior

    2016-05-01

    Full Text Available ABSTRACT: The present study aimed to evaluate five non-toxigenic strains of Clostridium difficile (NTCD in vitro and to select one strain to prevent C. difficile (CDI infection in hamsters ( Mesocricetus auratus . The NTCD strains were evaluated for spore production in vitro, antimicrobial susceptibility and presence of antimicrobial resistance genes. Approximately 107 spores of the selected strain (Z31 were administered by esophageal gavage in hamsters pretreated with 30mg kg-1 of clindamycin. The challenge with a toxigenic strain of C. difficile was conducted at 36 and 72h, and the animals were observed for 28 days. The NTCD strain of C. difficile (Z31 was able to prevent CDI in all animals that received it.

  13. Effect of dietary fatty acids on metabolic rate and nonshivering thermogenesis in golden hamsters.

    Science.gov (United States)

    Jefimow, Małgorzata; Wojciechowski, Michał S

    2014-02-01

    Hibernating rodents prior to winter tend to select food rich in polyunsaturated fatty acids (PUFA). Several studies found that such diet may positively affect their winter energy budget by enhancing torpor episodes. However, the effect of composition of dietary fatty acids (FA) on metabolism of normothermic heterotherms is poorly understood. Thus we tested whether diets different in FA composition affect metabolic rate (MR) and the capacity for nonshivering thermogenesis (NST) in normothermic golden hamsters (Mesocricetus auratus). Animals were housed in outdoor enclosures from May 2010 to April 2011 and fed a diet enriched with PUFA (i.e., standard food supplemented weekly with sunflower and flax seeds) or with saturated and monounsaturated fatty acids (SFA/MUFA, standard food supplemented with mealworms). Since diet rich in PUFA results in lower MR in hibernating animals, we predicted that PUFA-rich diet would have similar effect on MR of normothermic hamsters, that is, normothermic hamsters on the PUFA diet would have lower metabolic rate in cold and higher NST capacity than hamsters supplemented with SFA/MUFA. Indeed, in winter resting metabolic rate (RMR) below the lower critical temperature was higher and NST capacity was lower in SFA/MUFA-supplemented animals than in PUFA-supplemented ones. These results suggest that the increased capacity for NST in PUFA-supplemented hamsters enables them lower RMR below the lower critical temperature of the thermoneural zone. © 2013 Wiley Periodicals, Inc.

  14. Vasopressin differentially modulates aggression and anxiety in adolescent hamsters administered anabolic steroids.

    Science.gov (United States)

    Morrison, Thomas R; Ricci, Lesley A; Melloni, Richard H

    2016-11-01

    Adolescent Syrian hamsters (Mesocricetus auratus) treated with anabolic/androgenic steroids display increased offensive aggression and decreased anxiety correlated with an increase in vasopressin afferent development, synthesis, and neural signaling within the anterior hypothalamus. Upon withdrawal from anabolic/androgenic steroids, this neurobehavioral relationship shifts as hamsters display decreased offensive aggression and increased anxiety correlated with a decrease in anterior hypothalamic vasopressin. This study investigated the hypothesis that alterations in anterior hypothalamic vasopressin neural signaling modulate behavioral shifting between adolescent anabolic/androgenic steroid-induced offensive aggression and anxiety. To test this, adolescent male hamsters were administered anabolic/androgenic steroids and tested for offensive aggression or anxiety following direct pharmacological manipulation of vasopressin V1A receptor signaling within the anterior hypothalamus. Blockade of anterior hypothalamic vasopressin V1A receptor signaling suppressed offensive aggression and enhanced general and social anxiety in hamsters administered anabolic/androgenic steroids during adolescence, effectively reversing the pattern of behavioral response pattern normally observed during the adolescent exposure period. Conversely, activation of anterior hypothalamic vasopressin V1A receptor signaling enhanced offensive aggression in hamsters exposed to anabolic/androgenic steroids during adolescence. Together, these findings suggest that the state of vasopressin neural development and signaling in the anterior hypothalamus plays an important role in behavioral shifting between aggression and anxiety following adolescent exposure to anabolic/androgenic steroids. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Central amygdalar nucleus treated with orexin neuropeptides evoke differing feeding and grooming responses in the hamster.

    Science.gov (United States)

    Alò, Raffaella; Avolio, Ennio; Mele, Maria; Di Vito, Anna; Canonaco, Marcello

    2015-04-15

    Interaction of the orexinergic (ORXergic) neuronal system with the excitatory (glutamate, l-Glu) or the inhibitory (GABA) neurosignaling complexes evokes major homeostatic physiological events. In this study, effects of the two ORXergic neuropeptides (ORX-A/B) on their receptor (ORX-2R) expression changes were correlated to feeding and grooming actions of the hibernating hamster (Mesocricetus auratus). Infusion of the central amygdala nucleus (CeA) with ORX-A caused hamsters to consume notable quantities of food, while ORX-B accounted for a moderate increase. Interestingly the latter neuropeptide was responsible for greater frequencies of grooming with respect to both controls and the hamsters treated with ORX-A. These distinct behavioral changes turned out to be even greater in the presence of l-Glu agonist (NMDA) while the α1 GABAA receptor agonist (zolpidem, Zol) greatly reduced ORX-A-dependent feeding bouts. Moreover, ORX-A+NMDA mainly promoted greater ORX-2R expression levels with respect to ORX-A-treated hamsters while ORX-B+Zol was instead largely responsible for a down-regulatory trend. Overall, these features point to CeA ORX-2R sites as key sensory limbic elements capable of regulating eating and grooming responses, which may provide useful insights regarding the type of molecular mechanism(s) operating during feeding bouts. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. The influence of sex and diet on the characteristics of hibernation in Syrian hamsters.

    Science.gov (United States)

    Trefna, Marie; Goris, Maaike; Thissen, Cynthia M C; Reitsema, Vera A; Bruintjes, Jojanneke J; de Vrij, Edwin L; Bouma, Hjalmar R; Boerema, Ate S; Henning, Robert H

    2017-07-01

    Research on deep hibernators almost exclusively uses species captured from the wild or from local breeding. An exception is Syrian hamster (Mesocricetus auratus), the only standard laboratory animal showing deep hibernation. In deep hibernators, several factors influence hibernation quality, including body mass, sex and diet. We examined hibernation quality in commercially obtained Syrian hamsters in relation to body mass, sex and a diet enriched in polyunsaturated fatty acids. Animals (M/F:30/30, 12 weeks of age) were obtained from Harlan (IN, USA) and individually housed at 21 °C and L:D 14:10 until 20 weeks of age, followed by L:D 8:16 until 27 weeks. Then conditions were changed to 5 °C and L:D 0:24 for 9 weeks to induce hibernation. Movement was continuously monitored with passive infrared detectors. Hamsters were randomized to control diet or a diet 3× enriched in linoleic acid from 16 weeks of age. Hamsters showed a high rate of premature death (n = 24, 40%), both in animals that did and did not initiate torpor, which was unrelated to body weight, sex and diet. Time to death (31.7 ± 3.1 days, n = 12) or time to first torpor bout (36.6 ± 1.6 days, n = 12) was similar in prematurely deceased hamsters. Timing of induction of hibernation and duration of torpor and arousal was unaffected by body weight, sex or diet. Thus, commercially obtained Syrian hamsters subjected to winter conditions showed poor survival, irrespective of body weight, sex and diet. These factors also did not affect hibernation parameters. Possibly, long-term commercial breeding from a confined genetic background has selected against the hibernation trait.

  17. Carcinoma de células escamosas em epitélio nasal de um hamster chinês: relato de caso

    OpenAIRE

    Rosolem, Mayara Caroline [UNESP; Romero, Débora Cristina; Rozza, Daniela Bernadete [UNESP; Souza, Natalia Cristina de [UNESP; Simões, Daniel Castendo

    2012-01-01

    The squamous cell carcinoma (SCC) is a neoplasm that affect pets, production animals and exotic animals, and it’s very common in tropical countries like Brazil, once it develops a sparsely pigmented, stratified squamous epithelium and on surfaces mucosa exposed to ultraviolet action. The SCC is quite infiltrative but rarely causes metastases. Its occurrence in the nasal epithelium is widely reported in cats. This case is a chinese hamster (Cricetulus griséus), female, young, who developed a n...

  18. Different palm oil preparations reduce plasma cholesterol concentrations and aortic cholesterol accumulation compared to coconut oil in hypercholesterolemic hamsters.

    Science.gov (United States)

    Wilson, Thomas A; Nicolosi, Robert J; Kotyla, Timothy; Sundram, Kalyana; Kritchevsky, David

    2005-10-01

    Several studies have reported on the effect of refined, bleached and deodorized palm oil (RBD-PO) incorporation into the diet on blood cholesterol concentrations and on the development of atherosclerosis. However, very little work has been reported on the influence of red palm oil (RPO), which is higher in carotenoid and tocopherol content than RBD-PO. Thus, we studied the influence of RPO, RBD-PO and a RBD-PO plus red palm oil extract (reconstituted RBD-PO) on plasma cholesterol concentrations and aortic accumulation vs. hamsters fed coconut oil. Forty-eight F1B Golden Syrian hamsters (Mesocricetus auratus) (BioBreeders, Watertown, MA) were group housed (three/cage) in hanging polystyrene cages with bedding in an air-conditioned facility maintained on a 12-h light/dark cycle. The hamsters were fed a chow-based hypercholesterolemic diet (HCD) containing 10% coconut oil and 0.1% cholesterol for 2 weeks at which time they were bled after an overnight fast and segregated into four groups of 12 with similar plasma cholesterol concentrations. Group 1 continued on the HCD, Group 2 was fed the HCD containing 10% RPO in place of coconut oil, Group 3 was fed the HCD containing 10% RBD-PO in place of coconut oil and Group 4 was fed the HCD with 10% reconstituted RBD-PO for an additional 10 weeks. Plasma total cholesterol (TC) and non-high-density lipoprotein-cholesterol (HDL-C) (very low- and low-density lipoprotein) concentrations were significantly lower in the hamsters fed the RPO (-42% and -48%), RBD-PO (-32% and -36%) and the reconstituted RBD-PO (-37% and -41%) compared to the coconut oil-fed hamsters. Plasma HDL-C concentrations were significantly higher by 14% and 31% in hamsters fed the RBD-PO and RPO compared to the coconut oil-fed hamsters. Plasma triglyceride (TG) concentrations were significantly lower in hamsters fed RBD-PO (-32%) and the reconstituted RBD-PO (-31%) compared to the coconut oil-fed hamsters. The plasma gamma-tocopherol concentrations were higher

  19. Avaliação quantitativa da evolução da tuberculose em hamsters tratados 8 semanas consecutivas com Triclorfon e infectados com Mycobacterium bovis, cepa AN5

    OpenAIRE

    José Soares Ferreira Neto; Sonia Regina Pinheiro; Zenaide Maria Moraes; Luiz Carlos Sá Rocha; Idércio Luiz Sinhorini; Fumio Homma Ito; Silvio Arruda Vasconcellos

    1996-01-01

    A evolução da doença causada pela inoculação intraperitoneal de Mycobacterium bovis (cepa AN5) foi avaliada em hamsters (Mesocrícetus auratus) tratados de segundas a sextas-feiras, com doses subcutâneas de 30 mg/kg de Triclorfon, por um período de 8 semanas consecutivas. Os critérios adotados para essa avaliação foram o tempo de sobrevivência após a inoculação e a quantificação do agente no baço, fígado, rim e pulmão colhidos aos 1, 15, 29 e 45 dias após a inoculação. Nessas oportunidades ...

  20. Experimental paracoccidioidomycosis in hamster: transmission electron microscopy of inoculation site lesion Paracoccidioidomicose experimental em hamster: microscopía eletrônica de transmissão da lesão do local de inoculação

    Directory of Open Access Journals (Sweden)

    K. I. R. Coelho

    1994-06-01

    Full Text Available Interaction between Paracoccidioides brasiliensis (Pb and inflammatory cells in hamster testis was studied sequentially by transmission electron microscopy. In early lesions (six hours after inoculation, polymorphonuclear neutrophils (PMNs were the major and mononuclear cells and eosinophils were the minor constituents of the inflammatory cells. PMNs were later replaced by mononuclear cells. Viable Pb cells were phagocytosed or surrounded by inflammatory cells. Preserved Pb cells usually had broad host-parasite interphases, whereas dying ones had narrow interphases. The outer layer of the fungus wall was sometimes broken by PMN in some focal points, broken pieces being peeled off and phagocytosed. Small Pb cells were uninuclear, and were often related to broad interphase. Large Pb cells were multinucleated with irregularly shaped wall, and sometimes had lomasome and/or myelin like structures. Different interaction patterns of Pb with inflammatory cells may be due to functionally different host cell flow to the inoculation site or due to the age of Pb cells or both.Estudou-se sequencialmente, à microscopia eletrônica de transmissão, a interação entre Paracoccidioides brasiliensis (Pb e células inflamatórias em hamsters inoculados por via intratesticular. Seis horas após inoculações havia predominância de neutrófilos, estando presentes algumas células mononucleares e eosinófilos. Os neutrófilos foram progressivamente substituídos por células mononucleares. Fungos viáveis apresentavam-se fagocitados ou circunscritos por células inflamatórias, geralmente com ampla interface hospedeiro-parasita. Fungos mortos ou degenerados eram acompanhados de interfase estreita. A camada externa da parede do Pb era às vezes quebrada quando em contacto com neutrófilos, em vários pontos, sendo os fragmentos dessa parede descamados e fagocitados. Células fúngicas pequenas com um único núcleo se relacionavam com ampla interfase enquanto as c

  1. Involvement of Pro-Inflammatory Macrophages in Liver Pathology of Pirital Virus-Infected Syrian Hamsters

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    Corey L. Campbell

    2018-05-01

    Full Text Available New World arenaviruses cause fatal hemorrhagic disease in South America. Pirital virus (PIRV, a mammarenavirus hosted by Alston’s cotton rat (Sigmodon alstoni, causes a disease in Syrian golden hamsters (Mesocricetus auratus (biosafety level-3, BSL-3 that has many pathologic similarities to the South American hemorrhagic fevers (BSL-4 and, thus, is considered among the best small-animal models for human arenavirus disease. Here, we extend in greater detail previously described clinical and pathological findings in Syrian hamsters and provide evidence for a pro-inflammatory macrophage response during PIRV infection. The liver was the principal target organ of the disease, and signs of Kupffer cell involvement were identified in mortally infected hamster histopathology data. Differential expression analysis of liver mRNA revealed signatures of the pro-inflammatory response, hematologic dysregulation, interferon pathway and other host response pathways, including 17 key transcripts that were also reported in two non-human primate (NHP arenavirus liver-infection models, representing both Old and New World mammarenavirus infections. Although antigen presentation may differ among rodent and NHP species, key hemostatic and innate immune-response components showed expression parallels. Signatures of pro-inflammatory macrophage involvement in PIRV-infected livers included enrichment of Ifng, Nfkb2, Stat1, Irf1, Klf6, Il1b, Cxcl10, and Cxcl11 transcripts. Together, these data indicate that pro-inflammatory macrophage M1 responses likely contribute to the pathogenesis of acute PIRV infection.

  2. Age-associated metabolic and morphologic changes in mitochondria of individual mouse and hamster oocytes.

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    Fatma Simsek-Duran

    Full Text Available BACKGROUND: In human oocytes, as in other mammalian ova, there is a significant variation in the pregnancy potential, with approximately 20% of oocyte-sperm meetings resulting in pregnancies. This frequency of successful fertilization decreases as the oocytes age. This low proportion of fruitful couplings appears to be influenced by changes in mitochondrial structure and function. In this study, we have examined mitochondrial biogenesis in both hamster (Mesocricetus auratus and mouse (Mus musculus ova as models for understanding the effects of aging on mitochondrial structure and energy production within the mammalian oocyte. METHODOLOGY/PRINCIPAL FINDINGS: Individual metaphase II oocytes from a total of 25 young and old mice and hamsters were collected from ovarian follicles after hormone stimulation and prepared for biochemical or structural analysis. Adenosine triphosphate levels and mitochondrial DNA number were determined within individual oocytes from young and old animals. In aged hamsters, oocyte adenosine triphosphate levels and mitochondrial DNA molecules were reduced 35.4% and 51.8%, respectively. Reductions of 38.4% and 44% in adenosine triphosphate and mitochondrial genomes, respectively, were also seen in aged mouse oocytes. Transmission electron microscopic (TEM analysis showed that aged rodent oocytes had significant alterations in mitochondrial and cytoplasmic lamellae structure. CONCLUSIONS/SIGNIFICANCE: In both mice and hamsters, decreased adenosine triphosphate in aged oocytes is correlated with a similar decrease in mtDNA molecules and number of mitochondria. Mitochondria in mice and hamsters undergo significant morphological change with aging including mitochondrial vacuolization, cristae alterations, and changes in cytoplasmic lamellae.

  3. Sand fly captures with Disney traps in area of occurrence of Leishmania (Leishmania amazonensis in the state of Mato Grosso do Sul, mid-western Brazil Capturas de flebotomíneos com armadilhas de Disney em área de ocorrência de Leishmania (Leishmania amazonensis no estado de Mato Grosso do Sul, região Centro-Oeste do Brasil

    Directory of Open Access Journals (Sweden)

    Maria Elizabeth Cavalheiros Dorval

    2010-10-01

    Full Text Available INTRODUCTION: The work was conducted to study phlebotomine fauna (Diptera: Psychodidae and aspects of American cutaneous leishmaniasis transmission in a forested area where Leishmania (Leishmania amazonensis occurs, situated in the municipality of Bela Vista, State of Mato Grosso do Sul, Brazil. METHODS: The captures were conducted with modified Disney traps, using hamster (Mesocricetus auratus as bait, from May 2004 to January 2006. RESULTS: Ten species of phlebotomine sandflies were captured: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni and Sciopemyia sordellii. The two predominant species were Ev bourrouli (57.3% and Bi flaviscutellata (41.4%, present at all sampling sites. Two of the 36 hamsters used as bait presented natural infection with Leishmania. The parasite was identified as Leishmania (Leishmania amazonensis. CONCLUSIONS: Analysis of the results revealed the efficiency of Disney traps for capturing Bichromomyia flaviscutellata and the simultaneous presence of both vector and the Leishmania species transmitted by the same can be considered a predictive factor of the occurrence of leishmaniasis outbreaks for the human population that occupies the location.INTRODUÇÃO: O estudo foi realizado com o objetivo de estudar a fauna de flebotomíneos (Diptera: Psychodidae e aspectos ligados à transmissão da leishmaniose tegumentar americana em uma área florestal com ocorrência de Leishmania (Leishmania amazonensis, situada no município de Bela Vista, Estado do Mato Grosso do Sul, Brasil. MÉTODOS: As capturas de flebotomíneos foram realizadas utilizando-se armadilhas tipo Disney modificadas, com isca roedor, Mesocricetus auratus, no período de maio de 2004 a janeiro de 2006. RESULTADOS: As coletas resultaram na identificação de 10 espécies de Phlebotominae

  4. Análise motivacional, causal e funcional da brincadeira em duas espécies de roedores Motivational, causal and functional analysis of play behavior in two rodent species

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    Mauro Luís Vieira

    2002-01-01

    Full Text Available A brincadeira é um fenômeno bastante comum em indivíduos jovens de diferentes espécies, principalmente mamíferos. O objetivo do presente artigo foi fazer uma revisão sobre pesquisas realizadas com roedores, mais especificamente hamsters dourados (Mesocricetus auratus e ratos albinos (Rattus norvegicus. Esses animais apresentam os mais altos índices de complexidade de brincadeira e são os mais estudados em laboratório nessa área, entre os roedores. Com base nos artigos da literatura pesquisada, conclui-se que a brincadeira: a é um sistema motivacional próprio que apresenta características que o diferencia de outros sistemas motivacionais; b é modulada pelo sexo e idade do indivíduo e dos parceiros envolvidos na interação social; e c o significado funcional pode estar relacionado com a preparação do indivíduo para viver em ambientes sociais e treinamento físico. Nesse sentido, a brincadeira pode ser relevante para se compreender aspectos do desenvolvimento comportamental e social.Play behavior is a very frequent phenomenon in juvenile individuals of various species, mainly mammals. The purpose of the present article is to review the studies in rodents, more specifically in golden hamsters (Mesocricetus auratus and albino rats (Rattus norvegicus. These animals show the highest indices of play complexity and are, among rodents, the animals most studied in the laboratory in this field of research. Through this review of the literature we conclude that play behavior: a is a motivational system in its own right and possesses characteristics that differentiate it from other motivational systems; b is modulated by the sex and age of individuals and of the partners involved in the social interaction; and c has a functional significance that may be related to physical training and the preparation of the individuals for life in a social environment. In this way, play behavior can be relevant to the understanding of aspects of behavioral

  5. Reduced aflatoxicosis in livers of hamsters fed a manganese sulfate supplement.

    Science.gov (United States)

    Hastings, C E; Llewellyn, G C

    1987-01-01

    Male, weanling Syrian hamsters (Mesocricetus auratus) were given (for 10 weeks) diets supplemented with manganese sulfate, aflatoxin, or a combination of both. All animals were killed and a histopathologic evaluation was performed on each liver to assess the influence of a manganese-supplemented diet on aflatoxicosis. Serum cholesterol and liver glycogen levels were also analyzed to further study the interaction of manganese and aflatoxin. Characteristic aflatoxin-induced precancerous histopathologic changes were observed in animals receiving the toxin. These changes included bile duct cell hyperplasia, enlarged nuclei, nuclear inclusions, and megala-hepatocytes. The dietary manganese addition to aflatoxin animals caused a slight reduction in the bile duct cell hyperplasia and significantly reduced the enlarged nuclei and nuclear inclusions. The latter indicates that the manganese may be influencing membrane chemistry. Animals receiving aflatoxin alone showed significantly increased serum cholesterol and liver glycogen. The cholesterol levels were significantly increased over the aflatoxin-induced levels when manganese was given in combination with the aflatoxin. The manganese lowered the increased liver glycogen levels caused by the aflatoxin. Dietary manganese shows some potential in suppressing several, but not all, of the aspects of developing aflatoxicosis in the hamster. The specific mode and site of action of manganese requires additional study.

  6. Blocking oxytocin receptors inhibits vaginal marking to male odors in female Syrian hamsters.

    Science.gov (United States)

    Martinez, Luis A; Albers, H Elliott; Petrulis, Aras

    2010-12-02

    In Syrian hamsters (Mesocricetus auratus), precopulatory behaviors such as vaginal scent marking are essential for attracting a suitable mate. Vaginal marking is dependent on forebrain areas implicated in the neural regulation of reproductive behaviors in rodents, including the medial preoptic/anterior hypothalamus (MPOA-AH). Within MPOA-AH, the neuropeptide oxytocin (OT) acts to facilitate copulation (lordosis), as well as ultrasonic vocalizations towards males. It is not known, however, if OT in this area also facilitates vaginal marking. In the present study, a specific oxytocin receptor antagonist (OTA) was injected into MPOA-AH of intact female Syrian hamsters to determine if oxytocin receptor-dependent signaling is critical for the normal expression of vaginal marking elicited by male, female, and clean odors. OTA injections significantly inhibited vaginal marking in response to male odors compared with vehicle injections. There was no effect of OTA on marking in response to either female or clean odors. When injected into the bed nucleus of the stria terminalis (BNST), a nearby region to MPOA-AH, OTA was equally effective in decreasing marking. Finally, the effects of OTA appear to be specific to vaginal marking, as OTA injections in MPOA-AH or BNST did not alter general locomotor activity, flank marking, or social odor investigation. Considered together, these results suggest that OT in MPOA-AH and/or BNST normally facilitates male odor-induced vaginal marking, providing further evidence that OT generally supports prosocial interactions among conspecifics. Copyright © 2010 Elsevier Inc. All rights reserved.

  7. Expression of ER-α and ER-β during peri-implantation period in uterus is essential for implantation and decidualization in golden hamster.

    Science.gov (United States)

    Kumar, Randhir; Yadav, Akhilesh; Pakrasi, P L

    2017-02-01

    The role of estrogen in embryo implantation in golden hamster (Mesocricetus auratus) is still ambiguous. In order to clarify it, we investigated the spatial distribution and expression of estrogen receptors, ER-α and ER-β in the uterus of pregnant hamster during peri-implantation period and identified the effect of estrogen receptor antagonist ICI-182,780 on the embryo implantation. We performed in vivo experiments on early pregnant hamsters involving treatment with ICI-182,780, an estrogen receptor antagonist. Immunohistochemistry, western blot analysis and quantitative PCR were employed to evaluate the spatio-temporal distribution and expression of ER-α and ER-β in the uterus of normal early pregnant and treated hamsters. Results showed that embryo implantation was completely absent in ICI-182,780 treated uterine horn while, normal implantation occurred in control and vehicle treated horns. Both the receptors were differentially expressed in the uterus of hamster from day 1 (D1) to day7 (D7). In contrast, treated horns without any implantation site showed no trace of any receptors. Protein and mRNA expression of both the receptors were high around the day of implantation while, ER-β expression was up-regulated on D7 of embryo implantation. P value˂0.05 is considered significant. Spatio-temporal expression of ERs in the uterus during peri-implantation period have crucial role for endometrium receptivity and implantation in hamster. Recurrent implantation failure is the devastating problem among the desirable couple and is mainly due to defect in endometrium receptivity. This study may provide a new insight to manage the problem of idiopathic infertility. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Inorganic elements determination in human and animal whole blood samples by X-ray fluorescence technique (EDXRF); Determinacao de elementos quimicos inorganicos em amostras de sangue total humano e de animais de experimentacao (hamster dourado e cavalo da raca crioula) pela tecnica de fluorescencia de raios X (EDXRF)

    Energy Technology Data Exchange (ETDEWEB)

    Redigolo, Marcelo Miyada

    2011-07-01

    Blood is a suspension of cells contained in a complex liquid called plasma. The term 'whole blood' refers to samples with both solid and liquid parts. Inorganic elements are responsible for essential functions, such as osmotic regulation, cardiac frequency and contractibility, blood clotting and neuromuscular excitability. The determination of inorganic elements in corporeal fluids such as blood, serum, plasma, tissue and urine is used as a monitor for a part or the whole organism. In this work, the X-Ray fluorescence technique (EDXRF) was used for the determination of inorganic elements in whole blood samples from humans and animals (golden hamsters, Mesocricetus auratus and crioula breed horses, Equus caballus). The reference intervals of Na (1788 - 1826 {mu}g g'-{sup 1}), Mg (63 - 75 {mu}g g{sup -1}), P (602 - 676 {mu}g g{sup -1}), S (1519 - 1718 {mu}g g{sup -1}), Cl (2743 - 2867 {mu}g g{sup -1}), K (1508 - 1630 {mu}g g{sup -1}), Ca (214 - 228 {mu}g g'-{sup 1}), Cu (4 -6 {mu}g g{sup -1}) e Zn (1 - 3 {mu}g g'-{sup 1}) were determined for human blood. The reference intervals, for golden hamster blood were found to be: Na (1714 - 1819 {mu}g g{sup -1}), Mg (51 - 79 {mu}g g{sup -1}), P (970 - 1080 {mu}g g{sup -1}), S (1231 - 1739 {mu}g g{sup -1}), Cl (2775 - 2865 {mu}g g{sup -1}), K (1968 - 2248 {mu}g g{sup -1}), Ca (209 - 257 {mu}g g-1), Cu (4 - 6 {mu}g g{sup -1}) e Zn (3 - 5 {mu}g g{sup -1}). The reference intervals, for crioula breed horse blood, showed to be: Na (1955 - 2013 {mu}g g{sup -1}), Mg (51 - 75 {mu}g g{sup -1}), P (443 - 476 {mu}g g{sup -1}), S (1038 - 1140 {mu}g g{sup -}'1), Cl (2388 - 2574 {mu}g g{sup -1}), K (1678 - 1753 {mu}g g{sup -1}), Ca (202 - 213 {mu}g g{sup -1}), Cu (4,1 - 4,5 {mu}g g{sup -1}) e Zn (2,0 - 2,2 {mu}g g{sup -1}). Comparative study between NAA and EDXRF, both techniques showed the same performance for the analyses of biological matrices. The results contribute for the establishment of reference

  9. Controle da eficácia de bacterinas antileptospirose: relação entre os resultados dos testes de inibição de crescimento de leptospiras in vitro com os do desafio in vivo em hamsters

    Directory of Open Access Journals (Sweden)

    Amane Paldês Gonçalves

    2013-10-01

    Full Text Available Foi efetuada a comparação em hamsters da proteção conferida e dos níveis de anticorpos induzidos por duas bacterinas comerciais antileptospirose. Os ensaios empregados foram o teste oficial de potência com desafio (TP, o ensaio proposto, teste de inibição de crescimento de leptospiras in vitro (ICLIV e a soroaglutinação microscópica (SAM. O protocolo de imunização foi representado por duas aplicações individuais de 0,25 mL das bacterinas, puras ou de suas diluições geométricas de razão dois variando de 200 a 51.200 para a bacterina A e de 200 a 3.200 para a bacterina B, por via subcutânea com o intervalo de 15 dias. Decorridos 15 dias da segunda aplicação de vacina, um grupo de animais foi desafiado com 0,2 mL de cultivos de leptospiras, por indivíduo, respectivamente dos sorovares Canicola (bacterinas A e B ou Kennewicki (bacterina A. Os números de doses infectantes empregados nos desafios foram de 100 e 631 respectivamente, para os sorovares Canicola e Kennewicki. Decorridos 21 dias do desafio, os grupos de animais utilizados nos testes de ICLIV e SAM foram sangrados e os seus soros foram reunidos em pools (n = 5. No TP, adotando-se os critérios internacionais, as bacterinas foram aprovadas. A comparação do desempenho das bacterinas para os sorovares adotados, segundo sua concentração, por meio das proporções de animais sobreviventes ao TP e a média dos títulos de anticorpos identificados no teste de ICLIV, indicou que um título igual ou superior a 0,77 log corresponde ao nível de aprovação da bacterina no TP.

  10. Reduced learning and memory performances in high-fat treated hamsters related to brain neurotensin receptor1 expression variations.

    Science.gov (United States)

    Fazzari, Gilda; Zizza, Merylin; Di Vito, Anna; Alò, Raffaella; Mele, Maria; Bruno, Rosalinda; Barni, Tullio; Facciolo, Rosa Maria; Canonaco, Marcello

    2018-03-13

    Recent indications are suggesting that high fat and sugar-enriched foods do not only evoke harmful physiological conditions, but they also endure evident structural alterations in cerebral regions controlling cognitive and feeding behaviors. Food consumption plus neuronal energy regulatory mechanisms seem to constitute a complex system assuring that food calories do not exceed body requirements. At the same time obesogenic-related properties of limbic feeding stations like the hypothalamus (HTH), hippocampus (HIP) and amygdala (AMY) tend to control eating habits through the interaction of distinct neuropeptides. For this purpose, it was our intention to correlate expression differences of a key anti-obesogenic neuropeptide receptor i.e. neurotensin1 (NTR1) on mnemonic performances in the hibernating hamster (Mesocricetus auratus) exposed to a high fat diet (HFD). Interestingly, these hamsters exhibited a notable enhanced (p < 0.01) body weight from the fifth on to the twelfth week of treatment, which was accompanied by elevated blood lipid cholesterolo and triglycerides and glucose levels. At the same time these hamsters provided diminished locomotor activities such as exploratory bouts, rearing and grooming behaviors. Of greater relevance was their very extreme (p < 0.001) inability of identifying new objects during novel object recognition (NOR) tests along with not having correctly chosen the chamber of the conditioned place preference (CPP) apparatus, which contained the gratifying reward. Surprisingly the altered behavioral plus mnemonic tasks of HFD hamsters were tightly related to elevated NTR1 expression changes in the above limbic sites thus proposing this neuronal system as a highly probable alternative for treating obesity-dependent mnemonic dysfunctions. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. [Influence of intake of vegetable oils on the in vitro intestinal absorption of glucose in golden hamsters].

    Science.gov (United States)

    González Barra, I; Escobar, M; Villarroel Guerra, M

    1995-12-01

    Male Hamsters (Mesocricetus aureatus) were fed standardized diets with 15% Rose hip, Sunflower, Olive or Coconut oil for four weeks, in order to determine the influence of vegetable oils with different degree of unsaturation over the intestinal absorption of glucose. The concentration of glucose in the serosal solution at 20, 40 and 60 minutes, was quantified in pieces of everted intestine of each animal, after the feeding period was over. A lower concentration of glucose was observed in the Olive group, although it was statistically significant only when compared to the Rose hip and Coconut oil group (P Rose hip and Coconut showed a similar pattern, even though they are oils with extreme and opposing degree of unsaturation. We explain this by the triggering of homeostatic mechanisms in the cellular membranes of the enterocytes when faced to a nutritional stress caused by the saturated and unsaturated fatty acids of those oils. We can conclude that the in vitro intestinal absorption of glucose in golden hamster is modified by dietary lipids. The lower absorption of glucose seen in the Olive group could be caused a specific action of a fatty acid or of its degree of unsaturation.

  12. Effect of Hibiscus sabdariffa extract on high fat diet-induced obesity and liver damage in hamsters.

    Science.gov (United States)

    Huang, To-Wei; Chang, Chia-Ling; Kao, Erl-Shyh; Lin, Jenq-Horng

    2015-01-01

    Obesity is a chronic metabolic disorder associated with an increase in adipogenesis and often accompanied with fatty liver disease. In this study, we investigated the anti-obesity effects of Hibiscus sabdariffa water extract (HSE) in vivo. Eight-weeks-old male mice were divided into six groups (n=8 per group) and were fed either normal feed, a high fat diet (HFD), HFD supplemented with different concentrations of HSE, or HFD supplemented with anthocyanin. After 10 weeks of feeding, all the blood and livers were collected for further analysis. Mesocricetus auratus hamster fed with a high-fat diet developed symptoms of obesity, as determined from their body weight change and from their plasma lipid levels. Meanwhile, HSE treatment reduced fat accumulation in the livers of hamsters fed with HFD in a concentration-dependent manner. Administration of HSE reduced the levels of liver cholesterol and triglycerides, which were elevated by HFD. Analysis of the effect of HSE on paraoxonase 1, an antioxidant liver enzyme, revealed that HSE potentially regulates lipid peroxides and protects organs from oxidation-associated damage. The markers of liver damage such as serum alanine aminotransferase and aspartate aminotransferase levels that were elevated by HFD were also reduced on HSE treatment. The effects of HSE were as effective as treatment with anthocyanin; therefore the anthocyanins present in the HSE may play a crucial role in the protection established against HFD-induced obesity. In conclusion HSE administration constitutes an effective and viable treatment strategy against the development and consequences of obesity.

  13. [Biliary calculi in the golden hamster. XXXVII. The prophylactic action of the creosote bush (Larrea tridentata) in pigmented cholelithiasis produced by vitamin A].

    Science.gov (United States)

    Granados, H; Cárdenas, R

    1994-01-01

    In the present work the results of an experiment performed in the golden hamster (Mesocricetus auratus), strain ChCM, are presented, in which the possible preventive action of pigment cholelithiasis by a powdered, desiccated, hydroalcoholic extract of leaves of "gobernadora" (Larrea tridentata) was studied. The extract was added to the lithogenic diet (basic diet + 25,000 I.U. of Vitamin A) at the 4% level; the hamsters were fed with the experimental diets during 70 days. The results showed that the group which received the diet with "gobernadora" did not develop pigment cholelithiasis, whereas the group that received the lithogenic diet alone developed cholelithiasis in 63% of cases. It is suggested that the active principle present in the leaves of "gobernadora", responsible for the prevention of the cholelithiasis is nordihydroguiaretic acid (NDGA), a potent antioxidant. On the other hand, the hamsters that received the diet containing "gobernadora" showed serious signs of toxicity and pathological changes, such as a marked reduction of growth, pronounced irritability and aggressiveness, and a marked hypoplasia both testicular and of the accessory sex glands.

  14. Parasite Burden in Hamsters Infected with Two Different Strains of Leishmania (Leishmania) infantum: “Leishman Donovan Units” versus Real-Time PCR

    Science.gov (United States)

    Moreira, Nádia das Dores; Vitoriano-Souza, Juliana; Roatt, Bruno Mendes; Vieira, Paula Melo de Abreu; Ker, Henrique Gama; de Oliveira Cardoso, Jamille Mirelle; Giunchetti, Rodolfo Cordeiro; Carneiro, Cláudia Martins; de Lana, Marta; Reis, Alexandre Barbosa

    2012-01-01

    To develop and test new therapeutics and immune prophylaxis strategies for visceral leishmaniasis (VL), understanding tissue parasitism evolution after experimental infection with Leishmania infantum is important. Experimental infection in a hamster model (Mesocricetus auratus) reproduces several typical aspects of canine and human VL that are closely related to the inoculum’s route. We quantified the parasitism in the liver and spleen of hamsters experimentally infected by various routes (intradermal, intraperitoneal, and intracardiac [IC]) and different strains of L. infantum (MHOM/BR/74/PP75 and Wild) and compared two different methodologies to evaluate tissue parasitism (Leishman Donovan units [LDU] and real-time qPCR). In addition, the quantification of specific total-IgG in the serum of uninfected and infected hamsters was determined by ELISA. The animals were followed for 1, 3, 6 and 9 months post-infection for survival analysis. We found that infection with the Wild strain by the IC route resulted in higher mortality. Positive antibody (IgG) responses were detected with higher peaks at 6 and 9 months in the IC group inoculated with PP75 strain. However, in animals infected with the Wild strain the IgG levels were elevated in all infected groups during all the time evaluated. We also observed by LDU analysis that the IC route lead to higher parasitism in the liver and spleen with both strains. Furthermore, qPCR showed higher sensitivity for identifying animals with low parasitic burden. In conclusion, qPCR can be useful for assessing parasitism in the spleen and liver of a hamster model infected with L. infantum independent of the route of infection, and this technique may become an essential tool for assessing parasite density in the hamster model after experimental treatment or immunization with potential vaccine candidates. PMID:23112869

  15. Evaluation of the radio modifier effect of propolis on chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with 60-CO; Avaliacao do efeito radiomodificador da propolis em celulas de ovario de hamster chines (CHO-K1) e em celulas tumorais de prostata (PC3), irradiadas com CO-60

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Geyza Spigoti

    2011-07-01

    In the last decades, it has been given a great interest to investigations concerning natural, effective, nontoxic compounds with radioprotective potential together with the increasing utilization of different types of ionizing radiation for various applications. Among them propolis, a resinous compound produced by honeybees (Apis mellifera), has been considered quite promising, since it presents several advantageous biological characteristics, i. e., anti-inflammatory, antimicrobial, anticarcinogenic, antioxidant and also free radical scavenging action. The purpose of the present study was to evaluate the effect of Brazilian propolis, collected in the State of Rio Grande do Sul, on Chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with {sup 60}Co {gamma} radiation. For this purpose, three interlinked parameters were analyzed: micronucleus induction, cell viability and clonogenic death. The choice of these parameters was justified by their biological significance, in addition to the fact that they are readily observable and measurable in irradiated cells. The cytogenetic data obtained showed a radioprotective effect of propolis (5-100 {mu}g/ml) in the induction of DNA damage for both cell lines, irradiated with doses of 1 - 4 Gy. The cytotoxicity assay, however, showed a prominent antiproliferative effect of propolis (50 - 400{mu}/ml) in PC3 cells irradiated with 5 G{gamma}. The survival curves obtained were adequately fitted by a linear-quadratic model, where the {alpha} coefficient was higher in CHO-K1 cells. Concerning the clonogenic capacity, PC3 cells were more radiosensitive than CHO-K1 cells at the higher doses of the survival curve. Propolis at the concentrations of 30 - 100 {mu}g/ml, did not influence the clonogenic potential of PC3 cells, since the survival curves, associated or not with propolis, were found similar, although the combined treatment in CHO-K1 cells exhibited a stimulating proliferative effect. The data

  16. Urethane influence in the urine formation in swiss rats and syrian hamster

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Marina F.; Silva, Natanael G.; Mesquita, Carlos Henrique de, E-mail: mflima@ipen.br, E-mail: ngsilva@ipen.br, E-mail: chmesqui@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Urethane is an anaesthetic agent with minimal cardiovascular and respiratory system depression with long-lasting (6-10h) effects. Its carcinogenic potential avoids it from veterinary use. Either, the knowledge of its effects over the circulating catecholamines (cortisone and corticosterone), with reflects in the muscles physiology, it is widely used in pharmacological studies in laboratory species. At the first minutes, Urethane induces a hyperglycaemia condition due the insulin concentration decrease, later than, the insulin concentration and the condition becomes in hypoglycaemia, but the Urethane interfering in the urine production mechanisms has not been described. It is accepted that the glycolic level would not interferes in the kidney function, except in chronic states, notably associated with insulin related diseases. The relative high biological half-life of {sup 177}Lu-Dotatate allows its use in biodistribution studies among small animals whose metabolic rates are so fast that would be impossible observe them with the most part of the labeled molecules. During the performance of a cross-species extrapolation study using Urethane as anaesthesia and {sup 177}Lu-Dotatate as metabolic tracer, was observed the Urethane influence over urine formation in Swiss rats and Syrian hamster (Mesocricetus auratus). The objective of this work is only describes the Urethane action over the urine production. Firstly, four male inbread Wistar Swiss rats ({+-}250 g), are anesthetized, with around 1200 mg/kg, i.p., in groups of two. One rat from each group get ahead to the injection of {sup 177}Lu-Dotatate and Gamma camera in vivo study, the second ones, anesthetized, waited under warming lights until more than one hour to initiate the biodistribution study. The scintillographical images shown the radiopeptide stopped at the kidneys and the urinary empty in the animals who attempt more than one hour before enter to radiopharmaceutical injection and Gamma camera imaging

  17. Urethane influence in the urine formation in swiss rats and syrian hamster

    International Nuclear Information System (INIS)

    Lima, Marina F.; Silva, Natanael G.; Mesquita, Carlos Henrique de

    2011-01-01

    Urethane is an anaesthetic agent with minimal cardiovascular and respiratory system depression with long-lasting (6-10h) effects. Its carcinogenic potential avoids it from veterinary use. Either, the knowledge of its effects over the circulating catecholamines (cortisone and corticosterone), with reflects in the muscles physiology, it is widely used in pharmacological studies in laboratory species. At the first minutes, Urethane induces a hyperglycaemia condition due the insulin concentration decrease, later than, the insulin concentration and the condition becomes in hypoglycaemia, but the Urethane interfering in the urine production mechanisms has not been described. It is accepted that the glycolic level would not interferes in the kidney function, except in chronic states, notably associated with insulin related diseases. The relative high biological half-life of 177 Lu-Dotatate allows its use in biodistribution studies among small animals whose metabolic rates are so fast that would be impossible observe them with the most part of the labeled molecules. During the performance of a cross-species extrapolation study using Urethane as anaesthesia and 177 Lu-Dotatate as metabolic tracer, was observed the Urethane influence over urine formation in Swiss rats and Syrian hamster (Mesocricetus auratus). The objective of this work is only describes the Urethane action over the urine production. Firstly, four male inbread Wistar Swiss rats (±250 g), are anesthetized, with around 1200 mg/kg, i.p., in groups of two. One rat from each group get ahead to the injection of 177 Lu-Dotatate and Gamma camera in vivo study, the second ones, anesthetized, waited under warming lights until more than one hour to initiate the biodistribution study. The scintillographical images shown the radiopeptide stopped at the kidneys and the urinary empty in the animals who attempt more than one hour before enter to radiopharmaceutical injection and Gamma camera imaging procedures. The rates

  18. Cross neutralizing antibodies in hamsters vaccinated with leptospiral bacterins produced with three serovars of serogroup Sejroe

    Directory of Open Access Journals (Sweden)

    Rosana Tabata

    2002-09-01

    Full Text Available Three leptospiral bacterins, produced with different serovars of Serogroup Sejroe, namely the hardjo (bacterin A, wolffi (bacterin B and guaricura (bacterin C, were evaluated in male hamsters (Mesocricetus auratus by comparing the agglutinating and neutralizing antibodies titers using microscopic agglutination (MAT and in vitro growth inhibition (GIT tests. The immunization schedule was based on two 1.0 mL doses of non-diluted formalininactivated whole culture bacterin given through subcutaneous route with 10-day interval. The challenge was performed ten days after the second vaccine dose, when the animals were inoculated with 0.2 mL of non-inactivated cultures of each serovar through intraperitoneal route. On the 21st post-challenge day (PCD, all animals were bled and their sera were joined in pools (n=8 and tested by MAT and GIT. All vaccinated and control animals presented no clinical signs of leptospirosis after the challenge, but the serovar guaricura was isolated from the kidneys of control animals on the 21st PCD. The MAT results showed cross agglutinins between serovars hardjo and wolffi, and between wolffi and guaricura. The GIT results revealed the presence of cross neutralizing antibodies between serovars wolffi or guaricura against hardjo, wolffi and guaricura. It was found that the tested strain of serovar hardjo did not produce detectable levels of neutralizing antibodies, indicating its poor immunogenicity.

  19. Effect of probiotic-fermented, genetically modified soy milk on hypercholesterolemia in hamsters.

    Science.gov (United States)

    Tsai, Tsung-Yu; Chen, Li-Ying; Pan, Tzu-Ming

    2014-02-01

    The rapid progress of biotechnology and molecular biology has led to genetically modified (GM) crops becoming a part of agricultural production. There are concerns that the issues of the functional ingredients in GM products have not been addressed, such as the bioactivities of soy proteins and isoflavones. This study aimed to investigate the effects of probiotic-fermented GM soy milk on hypercholesterolemia, and atherosclerotic risks in hamsters. One hundred and twelve male Golden Syrian hamsters (Mesocricetus auratus) were randomly assigned into 14 groups of 8 animals each. Normal- and high-cholesterol experimental diets were supplemented with GM or non-GM soy milk with or without probiotic-fermentation for 8 weeks. Serum and fecal lipid levels were measured. Moreover, aortic plaque in artery were stained, and thiobarbituric acid reactive substance content, super oxide dismutase activity and caralase activity were determined. GM or non-GM soy milk with or without probiotic-fermentation significantly decreased (p milk were not significantly different from TC levels in the non-GM soy milk group (p > 0.05). GM soy milk groups can reduce risk of developing atherosclerosis through lowered oxidative stress and reduced atherosclerotic plaque formation in the aorta, and are thus at least equivalent to non-GM soy milk. GM soy milk with or without probiotic-fermentation can improve hypercholesterolemia and reduce the risk of atherosclerosis, and is considered substantially equivalent to non-GM soy milk in terms of these bioactive functions. Copyright © 2012. Published by Elsevier B.V.

  20. Experimental chronic entrapment of the sciatic nerve in adult hamsters: an ultrastructural and morphometric study

    Directory of Open Access Journals (Sweden)

    Prinz R.A.D.

    2003-01-01

    Full Text Available Entrapment neuropathy is a group of clinical disorders involving compression of a peripheral nerve and interference with nerve function mostly through traction injury. We have investigated the chronic compression of peripheral nerves as an experimental procedure for detecting changes in ultrastructural nerve morphology. Adult hamsters (Mesocricetus auratus, N = 30 were anesthetized with a 25% pentobarbital solution and received a cuff around the right sciatic nerve. Left sciatic nerves were not operated (control group. Animals survived for varying times (up to 15 weeks, after which they were sacrificed and both sciatic nerves were immediately fixed with a paraformaldehyde solution. Experimental nerves were divided into segments based upon their distance from the site of compression (proximal, entrapment and distal. Semithin and ultrathin sections were obtained and examined by light and electron microscopy. Ultrastructural changes were qualitatively described and data from semithin sections were morphometrically analyzed both in control and in compressed nerves. We observed endoneurial edema along with both perineurial and endoneurial thickening and also the existence of whorled cell-sparse structures (Renaut bodies in the subperineurial space of compressed sciatic nerves. Morphometric analyses of myelinated axons at the compression sites displayed a remarkable increase in the number of small axons (up to 60% in comparison with the control axonal number. The distal segment of compressed nerves presented a distinct decrease in axon number (up to 40% comparatively to the control group. The present experimental model of nerve entrapment in adult hamsters was shown to promote consistent histopathologic alterations analogous to those found in chronic compressive neuropathies.

  1. Modulation of the regression of atherosclerosis in the hamster by dietary lipids: comparison of coconut oil and olive oil.

    Science.gov (United States)

    Mangiapane, E H; McAteer, M A; Benson, G M; White, D A; Salter, A M

    1999-11-01

    The Golden Syrian hamster (Mesocricetus auratus) has been shown to be a useful model of both human lipoprotein metabolism and the development of atherosclerosis. We report the effects of dietary lipids on the progression and regression of atherosclerosis in this model. In the first study, hamsters fed on coconut oil (150 g/kg diet) and cholesterol (30 g/kg diet) developed lipid-rich lesions in the ascending aorta (0.28 (SD 0.14) mm2) and aortic arch (0.01 (SD 0.01) mm2) after 4 weeks that continued to progress over the next 8 weeks (0.75 (SD 0.41) mm2 and 0.12 (SD 0.11) mm2 for the ascending aorta and aortic arch respectively). Removal of cholesterol from the diet halted this progression. Furthermore, in animals fed on olive oil in the absence of added cholesterol, plasma LDL-cholesterol concentrations were lower (P coconut oil (with no added cholesterol). In a second study, animals were fed on the atherogenic diet for 10 weeks, transferred to diets containing either coconut oil (150 g/kg diet) or olive oil (150 g/kg diet) without added cholesterol and monitored for up to 16 weeks. In the ascending aorta, lesion size doubled in animals fed on coconut oil but stabilized in those fed on olive oil. In the aortic arch, lesion size decreased linearly (P coconut oil and olive oil respectively) with the greatest reduction being seen in the olive-oil-fed animals (P cholesterol and HDL-cholesterol in the plasma. We conclude that the male Golden Syrian hamster represents a useful model of dietary induced regression as well as progression of atherosclerosis.

  2. Investigation on the presence of leptospires in ovaries of hamsters experimentally infected whith Leptospiras interrogans serovar pomona

    Directory of Open Access Journals (Sweden)

    Claudio Roberto de Almeida Camargo

    1993-12-01

    Full Text Available After inoculating L. interrogans serovar pomona in 75 primiparous hamsters (Mesocricetus auratus, the invasiveness of leptospires into lhe ovaries and lhe ability in causing ovary morphologic alterations were investigated by means of microscopic examination and bacterial isolation. For this purpose, 75 hamsters were inoculated with 0.5 ml of virulent strain containing 30-40 leptospires by the microscopic field and the other 15 hamsters were held as the uninfected controls. Signs and symptoms (prostration, tachypnea, rufled hair, jaundice, and nasal, bucal and perineal hemorrage were detected in all inoculated animals. The animals were killed in the agonic state of the illness, which were done through 4th and 7th day post inoculation. The ovaries were taken asseptically during the necropsies, thoroughly washed using the sterile phosphate buffered saline, in order to eliminate the possible external contamination. The fresh ovary samples were submitted to the dark field direct microscopic examination. After the formalin fixation, the specimens were stained by means of histopathologic techniques using the Levaditi and Hematoxylin Eosin stains. The ovary smears were also examined by the direct fluorescent antibody technique andlhe bacterial isolation was carried out in the Fletcher’s medium. The dark field direct microscopic examination was found tobe less sensitive in demonstrating the presence of leptospiresin the ovaries. In those specimens stained by the Lcvadititechnique, leptospires were visualized in different ovaryinternal structures, involving the interspace, pellucid zone andin the inner ovules. Through the histopathologic examination,typical morphologic alterations resembling acute infiamatoryprocess were found in 57% of ovaries examined.

  3. Peroral Echinococcus multilocularis egg inoculation in Myodes glareolus, Mesocricetus auratus and Mus musculus (CD-1 IGS and C57BL/6j)

    DEFF Research Database (Denmark)

    Woolsey, Ian David; Jensen, Per Moestrup; Deplazes, Peter

    2016-01-01

    Echinococcus multilocularis transmission predominantly occurs in Europe between the red fox (Vulpes vulpes) and various species of rodent intermediate hosts. We infected 3 species of rodent, Myodes glareolus (n = 47), Mesocricetus auratus (n = 11) and outbred Mus musculus (CD-1 IGS) (n = 9...

  4. Capacitação espermática de sêmem congelado de onça pintada (Panthera onca e ensaio de penetração em oócitos de hamster livres de zona pelúcida

    Directory of Open Access Journals (Sweden)

    Regina Celia Rodrigues da Paz

    2007-10-01

    Full Text Available Biotecnologias reprodutivas aplicadas a espécies selvagens, como inseminação artificial, fertilização in vitro e transferência de embriões, são vistas como um potencial caminho para proteção das espécies ameaçadas de extinção. Devido a isso, o objetivo deste estudo foi avaliar a fertilidade do sêmen congelado de onças pintadas (Panthera onca e o meio de capacitação espermática usando o ensaio de penetração em oócitos de hamster livres de zona pelúcida. Ejaculados de nove animais foram coletados por eletroejaculação e criopreservados. Para determinar a capacitação espermática foi utilizada a técnica swin-up com meio Tyrods Talp PVA a temperatura ambiente. No ensaio de penetração em oócitos de hamster livres de zona pelúcida foram considerados como oócitos penetrados aqueles que apresentaram em seu interior a cabeça do espermatozóide descondensada. O ensaio foi realizado em um total de 2275 oócitos, dos quais 350 apresentaram em seu interior a cabeça do espermatozóide descondensada, perfazendo um total de 15.4% de penetração. Os resultados deste estudo demonstraram alto índice de anormalidades espermáticas, baixa qualidade do sêmen e baixa porcentagem de penetrações. Entretanto, os resultados de penetração espermática demonstraram que sêmen congelado de onça pintada poderá ser utilizado para inseminação artificial, fertilização in vitro e injeção intracitoplasmática dando suporte para a criação de um banco de sêmen para esta espécie.

  5. Sensibility of the hamster (Cricetus auratus to the Treponema pertenue

    Directory of Open Access Journals (Sweden)

    F. Nery-Guimarães

    1955-05-01

    Full Text Available In two experiments, 8 Hamsters inoculated with material from yaws lesions (Treponema pertenue, developed skin lesions considered specific by their clinical and histopathological aspects and by the presence of treponemae. These lesions appeared on the scrotumm, testicle, prepuce, anus, tail, muzzle, back and hinders paws (palm surface. In the internal organs no treponemae were found in direct examinations and inoculation of brain, spleen and lymph node. The incubation period was of 35 days for the testicle, 55 days for the scrotum and 107 days for peritoneal cavity inoculation. Positive sub-inoculations were obtained. The serum reactions (Qasserman's and Kahn's were negative in all 5 tested Hamsters. Out of 4 normal females matched to infected males two developed nasal lesions resulting from direct contact. Apparently the genital lesions hindered copulation. Hamsters are very well suited for an experimental study of yaws.Em 2 experiências, 8 Hamsters inoculados com material direto de lesões boubáticas (Treponema pertenue, desenvolveram lesões cutâneas consideradas específicas, pelo aspecto clínico e histopatológico e pela presentça de treponemas. Essas lesões se manifestaram no escrôto, testículo, prepúcio, anus, cauda, focinho, dorso e patas posteriores (face palmar. Nos órgãos internos não foram vistos treponemas ao exame direto e, uma vez, por inoculação de cérebro, baço e gânglio linfático. O período incubativo foi de 35 dias pela via testicular, 55 dias pela via escrotal e 107 dias pela via peritonial. Foram obtidas sub-inoculações positivas para Hamsters normais. As experiências continuam. De 4 fêmeas normais, acasaladas com 4 hamsters infectados apenas 2 mostraram lesões positivas resultantes de contágio direto. Aparentemente, não houve copulação e, se esta ocorreu, não determinou fecundação.

  6. GABA Neural Signaling in the Latero-Anterior Hypothalamus Modulates Aggressive Behavior in Adolescent Anabolic/Androgenic Steroid-Treated Hamsters

    Science.gov (United States)

    Morrison, Thomas R.; Ricci, Lesley A.; Melloni, Richard H.

    2014-01-01

    Male Syrian hamsters (Mesocricetus auratus) treated with anabolic/androgenic steroids (AAS) during adolescence (P27–P56) display highly escalated and mature forms of offensive aggression correlated with increased γ-aminobutyric acid (GABA) afferent development as well as decreased GABAA receptors in the latero-anterior hypothalamus (LAH) – an area of convergence for developmental and neuroplastic changes that underlie offensive aggressive behaviors in hamsters. This study investigated whether microinfusion of a GABAA receptor agonist (muscimol; 0.01 – 1.0 pM) or antagonist (bicuculline; 0.04 – 4.0 pM) directly into the LAH modulate adolescent AAS-induced offensive aggression. Activation of LAH GABAA receptors enhanced adolescent AAS-induced offensive aggression, beginning at the 0.1pM dose, when compared with AAS-treated animals injected with saline into the LAH. Importantly, GABAA receptor agonism within the LAH significantly increased the frequency of belly/rear attacks, while simultaneously decreasing the frequency of frontal attacks. These data identify a neuroanatomical locus where GABAA receptor activation functions to enhance aggression in adolescent AAS-treated animals, while also promoting the display of mature forms of aggression and suppressing juvenile play behaviors. PMID:25171080

  7. Decreases in body temperature and body mass constitute pre-hibernation remodelling in the Syrian golden hamster, a facultative mammalian hibernator

    Science.gov (United States)

    Chayama, Yuichi; Ando, Lisa; Tamura, Yutaka; Miura, Masayuki

    2016-01-01

    Hibernation is an adaptive strategy for surviving during periods with little or no food availability, by profoundly reducing the metabolic rate and the core body temperature (Tb). Obligate hibernators (e.g. bears, ground squirrels, etc.) hibernate every winter under the strict regulation of endogenous circannual rhythms, and they are assumed to undergo adaptive remodelling in autumn, the pre-hibernation period, prior to hibernation. However, little is known about the nature of pre-hibernation remodelling. Syrian hamsters (Mesocricetus auratus) are facultative hibernators that can hibernate irrespective of seasons when exposed to prolonged short photoperiod and cold ambient temperature (SD-Cold) conditions. Their Tb set point reduced by the first deep torpor (DT) and then increased gradually after repeated cycles of DT and periodic arousal (PA), and finally recovered to the level observed before the prolonged SD-Cold in the post-hibernation period. We also found that, before the initiation of hibernation, the body mass of animals decreased below a threshold, indicating that hibernation in this species depends on body condition. These observations suggest that Syrian hamsters undergo pre-hibernation remodelling and that Tb and body mass can be useful physiological markers to monitor the remodelling process during the pre-hibernation period. PMID:27152216

  8. Effect of Hibiscus sabdariffa extract on high fat diet–induced obesity and liver damage in hamsters

    Directory of Open Access Journals (Sweden)

    To-Wei Huang

    2015-10-01

    Full Text Available Background: Obesity is a chronic metabolic disorder associated with an increase in adipogenesis and often accompanied with fatty liver disease. Objective: In this study, we investigated the anti-obesity effects of Hibiscus sabdariffa water extract (HSE in vivo. Method: Eight-weeks-old male mice were divided into six groups (n=8 per group and were fed either normal feed, a high fat diet (HFD, HFD supplemented with different concentrations of HSE, or HFD supplemented with anthocyanin. After 10 weeks of feeding, all the blood and livers were collected for further analysis. Results: Mesocricetus auratus hamster fed with a high-fat diet developed symptoms of obesity, as determined from their body weight change and from their plasma lipid levels. Meanwhile, HSE treatment reduced fat accumulation in the livers of hamsters fed with HFD in a concentration-dependent manner. Administration of HSE reduced the levels of liver cholesterol and triglycerides, which were elevated by HFD. Analysis of the effect of HSE on paraoxonase 1, an antioxidant liver enzyme, revealed that HSE potentially regulates lipid peroxides and protects organs from oxidation-associated damage. The markers of liver damage such as serum alanine aminotransferase and aspartate aminotransferase levels that were elevated by HFD were also reduced on HSE treatment. The effects of HSE were as effective as treatment with anthocyanin; therefore the anthocyanins present in the HSE may play a crucial role in the protection established against HFD-induced obesity. Conclusions: In conclusion HSE administration constitutes an effective and viable treatment strategy against the development and consequences of obesity.

  9. Effect of Hibiscus sabdariffa extract on high fat diet–induced obesity and liver damage in hamsters

    Science.gov (United States)

    Huang, To-Wei; Chang, Chia-Ling; Kao, Erl-Shyh; Lin, Jenq-Horng

    2015-01-01

    Background Obesity is a chronic metabolic disorder associated with an increase in adipogenesis and often accompanied with fatty liver disease. Objective In this study, we investigated the anti-obesity effects of Hibiscus sabdariffa water extract (HSE) in vivo. Method Eight-weeks-old male mice were divided into six groups (n=8 per group) and were fed either normal feed, a high fat diet (HFD), HFD supplemented with different concentrations of HSE, or HFD supplemented with anthocyanin. After 10 weeks of feeding, all the blood and livers were collected for further analysis. Results Mesocricetus auratus hamster fed with a high-fat diet developed symptoms of obesity, as determined from their body weight change and from their plasma lipid levels. Meanwhile, HSE treatment reduced fat accumulation in the livers of hamsters fed with HFD in a concentration-dependent manner. Administration of HSE reduced the levels of liver cholesterol and triglycerides, which were elevated by HFD. Analysis of the effect of HSE on paraoxonase 1, an antioxidant liver enzyme, revealed that HSE potentially regulates lipid peroxides and protects organs from oxidation-associated damage. The markers of liver damage such as serum alanine aminotransferase and aspartate aminotransferase levels that were elevated by HFD were also reduced on HSE treatment. The effects of HSE were as effective as treatment with anthocyanin; therefore the anthocyanins present in the HSE may play a crucial role in the protection established against HFD-induced obesity. Conclusions In conclusion HSE administration constitutes an effective and viable treatment strategy against the development and consequences of obesity. PMID:26475512

  10. Polymyopathy in a Syrian golden hamster

    NARCIS (Netherlands)

    Wijnands, M.V.W.; Woutersen, R.A.

    1996-01-01

    A Syrian golden hamster suffered from general swelling of skeletal muscles. At microscopical observation the muscle tissue exhibited degeneration and necrosis, as well as regenerative features. The inflammatory response was very slight. The histopathological lesions were diagnosed as polymyopathy.

  11. Induction of lyme arthritis in LSH hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, J.L.; Schell, R.F.; Hejka, A.; England, D.M.; Konick, L.

    1988-09-01

    In studies of experimental Lyme disease, a major obstacle has been the unavailability of a suitable animal model. We found that irradiated LSH/Ss Lak hamsters developed arthritis after injection of Borrelia burgdorferi in the hind paws. When nonirradiated hamsters were injected in the hind paws with B. burgdorferi, acute transient synovitis was present. A diffuse neutrophilic infiltrate involved the synovia and periarticular structures. The inflammation was associated with edema, hyperemia, and granulation tissue. Numerous spirochetes were seen in the synovial and subsynovial tissues. The histopathologic changes were enhanced in irradiated hamsters. The onset and duration of the induced swelling were dependent on the dose of radiation and the inoculum of spirochetes. Inoculation of irradiated hamsters with Formalin-killed spirochetes or medium in which B. burgdorferi had grown for 7 days failed to induce swelling. This animal model should prove useful for studies of the immune response to B. burgdorferi and the pathogenesis of Lyme arthritis.

  12. Track segment studies with Chinese hamster cells

    International Nuclear Information System (INIS)

    Bird, R.P.

    1984-01-01

    Survival curves of near-diploid and near-tetraploid Chinese hamster cell cultures following irradiation by an 241 Am α source indicate different growth rates for the two clones. Possible reasons for the difference are discussed

  13. Proteomic Analysis of Chinese Hamster Ovary Cells

    DEFF Research Database (Denmark)

    Baycin-Hizal, Deniz; Tabb, David L.; Chaerkady, Raghothama

    2012-01-01

    To complement the recent genomic sequencing of Chinese hamster ovary (CHO) cells, proteomic analysis was performed on CHO cells including the cellular proteome, secretome, and glycoproteome using tandem mass spectrometry (MS/MS) of multiple fractions obtained from gel electrophoresis, multidimens......To complement the recent genomic sequencing of Chinese hamster ovary (CHO) cells, proteomic analysis was performed on CHO cells including the cellular proteome, secretome, and glycoproteome using tandem mass spectrometry (MS/MS) of multiple fractions obtained from gel electrophoresis...

  14. Obesity without overeating in golden hamsters.

    Science.gov (United States)

    Wade, G N

    1982-10-01

    When male golden hamsters were switched from a diet of Purina rodent chow to a calorically-dense high-fat diet or were given ad lib access to a 32% sucrose solution in addition to chow, they adjusted their food intakes rapidly (within 24 hr) and did not overeat. Nevertheless, the fat-fed hamsters tripled their rate of weight gain and nearly doubled their carcass fat content after one month on the diet. Resting oxygen consumption (animals awake but quite) was significantly lower in fat-fed animals than in chow-fed controls. Sucrose feeding had no effect on food intake, body weight gain, carcass composition or oxygen consumption. Thus, whereas rats exhibit dietary obesity in spite of increases in energy expenditure (diet-induced thermogenesis), fat-fed hamsters seem to become obese because of decreases in energy expenditure. However, although actual energy expenditure is reduced, fat-fed hamsters exhibit an enhanced thermogenic capacity. Interscapular brown adipose tissue mass, protein content, and DNA content as well as norepinephrine-stimulated oxygen consumption were all significantly elevated in fat-fed hamsters. The significance of these concurrent diet-induced decreases in energy expenditure and increases in thermogenic capacity is not clear, but they could be of some value in preparing the hamster for winter.

  15. Cystolithiasis in a Syrian hamster: a different outcome | Petrini ...

    African Journals Online (AJOL)

    Considering the positive outcome and the beneficial properties of palmitoylethanolamide, glucosamine, and hesperidin, these nutritional elements in Syrian hamsters, are recommended to reduce recurrence after surgical treatment of urolithiasis. Keywords: Glucosamine, Hamster, Hesperidin, PEA, Urolithiasis ...

  16. Methods for modeling chinese hamster ovary (cho) cell metabolism

    DEFF Research Database (Denmark)

    2015-01-01

    Embodiments of the present invention generally relate to the computational analysis and characterization biological networks at the cellular level in Chinese Hamster Ovary (CHO) cells. Based on computational methods utilizing a hamster reference genome, the invention provides methods...

  17. Production and purification of polyclonal anti-hamster ...

    African Journals Online (AJOL)

    . ... IgG showed high titer and high specificity in the designed ELISA. Purified antibody and its conjugation with HRP are used in research and diagnosis of hamster disease. Key words: Production, purification, hamster immunoglobulins.

  18. Histopathology of Lyme arthritis in LSH hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Hejka, A.; Schmitz, J.L.; England, D.M.; Callister, S.M.; Schell, R.F.

    1989-05-01

    The authors studied the histopathologic evolution of arthritis in nonirradiated and irradiated hamsters infected with Borrelia burgdorferi. Nonirradiated hamsters injected in the hind paws with B. burgdorferi developed an acute inflammatory reaction involving the synovium, periarticular soft tissues, and dermis. This acute inflammatory reaction was short-lived and was replaced by a mild chronic synovitis as the number of detectable spirochetes in the synovium, periarticular soft tissues, and perineurovascular areas diminished. Exposing hamsters to radiation before inoculation with B. burgdorferi exacerbated and prolonged the acute inflammatory phase. Spirochetes also persisted longer in the periarticular soft tissues. A major histopathologic finding was destructive and erosive bone changes of the hind paws, which resulted in deformation of the joints. These studies should be helpful in defining the immune mechanism participating in the onset, progression, and resolution of Lyme arthritis.

  19. Safety and efficacy analysis of liposomal insulin-like growth factor-1 in a fluid gel formulation for hair-loss treatment in a hamster model.

    Science.gov (United States)

    Castro, R F; Azzalis, L A; Feder, D; Perazzo, F F; Pereira, E C; Junqueira, V B C; Rocha, K C; Machado, C D'A; Paschoal, F C; Gnann, L A; Fonseca, F L A

    2012-12-01

    Insulin-like growth factor (IGF)-1 has shown some interesting results in studies examining its use as a hair-loss treatment. IGF-1 works by regulating cellular proliferation and migration during the development of hair follicles. Hepatotoxicity and myelotoxicity were evaluated in hamsters (Mesocricetus auratus) after topical application of the liquid gel vehicle (placebo), 1% IGF-1 or 3% IGF-1. No significant difference in the levels of aspartate aminotransferase or alanine aminotransferase was found between the control and treated groups. ELISA did not shown any increase in the plasma level of IGF-1. A haematopoietic niche was found, but it was not associated with myelotoxicity. Efficacy was determined by dermatoscopy analysis of hair density and microscopy analysis of hair diameter, with hair found to be thicker and with more rapid growth in the 3% group than in either the 1% group or the control group. These results strongly suggest that liposomal IGF-1 in a liquid gel formulation is a safe and efficient treatment for hair loss. © The Author(s). CED © 2012 British Association of Dermatologists.

  20. Nipah virus transmission in a hamster model.

    Directory of Open Access Journals (Sweden)

    Emmie de Wit

    2011-12-01

    Full Text Available Based on epidemiological data, it is believed that human-to-human transmission plays an important role in Nipah virus outbreaks. No experimental data are currently available on the potential routes of human-to-human transmission of Nipah virus. In a first dose-finding experiment in Syrian hamsters, it was shown that Nipah virus was predominantly shed via the respiratory tract within nasal and oropharyngeal secretions. Although Nipah viral RNA was detected in urogenital and rectal swabs, no infectious virus was recovered from these samples, suggesting no viable virus was shed via these routes. In addition, hamsters inoculated with high doses shed significantly higher amounts of viable Nipah virus particles in comparison with hamsters infected with lower inoculum doses. Using the highest inoculum dose, three potential routes of Nipah virus transmission were investigated in the hamster model: transmission via fomites, transmission via direct contact and transmission via aerosols. It was demonstrated that Nipah virus is transmitted efficiently via direct contact and inefficiently via fomites, but not via aerosols. These findings are in line with epidemiological data which suggest that direct contact with nasal and oropharyngeal secretions of Nipah virus infected individuals resulted in greater risk of Nipah virus infection. The data provide new and much-needed insights into the modes and efficiency of Nipah virus transmission and have important public health implications with regards to the risk assessment and management of future Nipah virus outbreaks.

  1. Nipah Virus Transmission in a Hamster Model

    Science.gov (United States)

    de Wit, Emmie; Bushmaker, Trenton; Scott, Dana; Feldmann, Heinz; Munster, Vincent J.

    2011-01-01

    Based on epidemiological data, it is believed that human-to-human transmission plays an important role in Nipah virus outbreaks. No experimental data are currently available on the potential routes of human-to-human transmission of Nipah virus. In a first dose-finding experiment in Syrian hamsters, it was shown that Nipah virus was predominantly shed via the respiratory tract within nasal and oropharyngeal secretions. Although Nipah viral RNA was detected in urogenital and rectal swabs, no infectious virus was recovered from these samples, suggesting no viable virus was shed via these routes. In addition, hamsters inoculated with high doses shed significantly higher amounts of viable Nipah virus particles in comparison with hamsters infected with lower inoculum doses. Using the highest inoculum dose, three potential routes of Nipah virus transmission were investigated in the hamster model: transmission via fomites, transmission via direct contact and transmission via aerosols. It was demonstrated that Nipah virus is transmitted efficiently via direct contact and inefficiently via fomites, but not via aerosols. These findings are in line with epidemiological data which suggest that direct contact with nasal and oropharyngeal secretions of Nipah virus infected individuals resulted in greater risk of Nipah virus infection. The data provide new and much-needed insights into the modes and efficiency of Nipah virus transmission and have important public health implications with regards to the risk assessment and management of future Nipah virus outbreaks. PMID:22180802

  2. Effect of mebendazole on fibrosarcoma in hamsters

    African Journals Online (AJOL)

    1Department of Histology and Embryology, 2Department of Pharmacy, 3Department of Pharmacology, Toxicology and Clinical. Pharmacology ... Purpose: To investigate the effect of mebendazole on an in vivo solid tumor model of fibrosarcoma in hamsters. ..... cancer [16] and one case report of colon cancer. [14] can be ...

  3. Comparative mutagenicity of alkylsulfate and alkanesulfonate derivatives in Chinese hamster ovary cells.

    Science.gov (United States)

    Couch, D B; Forbes, N L; Hsie, A W

    1978-05-01

    Mutation induction and cell killing produced by selected alkylsulfates and alkanesulfonates have been quantitated using the Chinese hamster ovary/hypoxanthine--guanine phosphoribosyl transferase (CHO/HGPRT) system. Dose--response relationships of cytotoxicity and mutagenicity are presented for two alkylsulfates [dimethylsulfate (DMS), diethylsulfate (DES)] and three alkyl alkanesulfonates [methyl methanesulfonate (MMS), ethyl methanesulfonate (EMS), and isopropyl methanesulfonate (iPMS)]. Under the experimental conditions employed, cytotoxicity decreased with the size of the alkyl group. DMS was more toxic than DES, and MMS was more toxic than EMS and iPMS. All agents produced linear dose--response of mutation induction: DMS was more mutagenic than DES, and MMS was more mutagenic than EMS and iPMS based on mutants induced per unit mutagen concentration. However, the following relative mutagenic potency was observed when comparisons were made at 10% survival: DES greater than DMS; EMS greater than MMS greater than iPMS.

  4. Dominant white spotting in the Chinese hamster.

    Science.gov (United States)

    Henwood, C; Henwood, J; Robinson, R

    1987-01-01

    An autosomal dominant white spotting mutant is described for the Chinese hamster. The mutant gene is designated as dominant spot (symbol Ds). The homozygote DsDs is a prenatal lethal while the heterozygote Ds + displays white spotting. The expression of white is variable, ranging from a white forehead spot to extensive white on the body. The venter is invariably white. Growth appears to be normal and the fertility of both sizes shows no impairment.

  5. Oxytocin inhibits aggression in female Syrian hamsters.

    Science.gov (United States)

    Harmon, A C; Huhman, K L; Moore, T O; Albers, H E

    2002-12-01

    Dominant subordinate relationships are formed as the result of social conflict and are maintained at least in part by communication. At this time, little is known about the neural mechanisms that are responsible for coordinating the social behaviours (e.g. aggression) that occur in association with the formation and maintenance of these relationships. The purpose of the present study was to investigate the role of oxytocin (OXT) within the medial preoptic anterior hypothalamic continuum (MPOA-AH) in the control of aggression in female hamsters. OXT injected into the MPOA-AH immediately before testing significantly reduced the duration of aggression in a dose-dependent manner. Injection of an OXT antagonist 30 min before testing significantly increased the duration of aggression. In contrast, the duration of aggression was not altered when hamsters were tested either 30 min after injection of OXT or immediately following injection of an OXT-antagonist. These data support the hypothesis that OXT release within the MPOA-AH regulates social behaviours important in the formation and maintenance of dominant subordinate relationships in female hamsters.

  6. Recent progress with the DNA repair mutants of Chinese hamster ovary cells

    Energy Technology Data Exchange (ETDEWEB)

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

    1986-04-02

    Repair deficient mutants of Chinese hamster ovary (CHO) cells are being used to identify human genes that correct the repair defects and to study mechanisms of DNA repair and mutagenesis. Five independent tertiary DNA transformants were obtained from the EM9 mutant. In these clones a human DNA sequence was identified that correlated with the resistance of the cells to CldUrd. After Eco RI digestion, Southern transfer, and hybridization of transformant DNAs with the BLUR-8 Alu family sequence, a common fragment of 25 to 30 kb was present. 37 refs., 4 figs., 3 tabs.

  7. Recent progress with the DNA repair mutants of Chinese hamster ovary cells

    International Nuclear Information System (INIS)

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

    1986-01-01

    Repair deficient mutants of Chinese hamster ovary (CHO) cells are being used to identify human genes that correct the repair defects and to study mechanisms of DNA repair and mutagenesis. Five independent tertiary DNA transformants were obtained from the EM9 mutant. In these clones a human DNA sequence was identified that correlated with the resistance of the cells to CldUrd. After Eco RI digestion, Southern transfer, and hybridization of transformant DNAs with the BLUR-8 Alu family sequence, a common fragment of 25 to 30 kb was present. 37 refs., 4 figs., 3 tabs

  8. Production and purification of polyclonal anti-hamster ...

    African Journals Online (AJOL)

    user

    2011-01-17

    Jan 17, 2011 ... Purified antibody and its conjugation with HRP are used in research and diagnosis of hamster disease. Key words: Production, purification, hamster immunoglobulins. INTRODUCTION. Polyclonal antibodies represent a group or mixture of antibodies produced by different B-lymphocytes in res- ponse to the ...

  9. Radiation-induced anorexia in Syrian hamsters

    International Nuclear Information System (INIS)

    Kindt, A.; Sattler, E.L.; Schraub, A.

    1980-01-01

    The recovery of Syrian hamsters after split dose application (interval 11 days) was studied on the basis of the weight response and of food uptake. Two periods of weight loss and anorexia can be distinguished, an early one immediately after irradiation and a secondary one 6-10 days later. The secondary response is a function of the radiation dose and allows to distinguish survivors from non-survivors, since it is much more pronounced and longerlasting in the latter than in the former. The first response appears not to be influenced by a previous conditioning irradiation. (orig.) [de

  10. Efeito hipolipemiante e antioxidante de subprodutos da uva em hamsters

    OpenAIRE

    Emilia Yasuko Ishimoto

    2008-01-01

    Introdução: Recentes pesquisas têm indicado o enorme potencial de certas substâncias alimentares, como polifenóis antioxidantes e fibras na redução de riscos de doenças crônicas. O bagaço de uva, subproduto do processamento de vinhos e sucos, representa uma ótima fonte de fibras e antioxidantes naturais de baixo custo. Objetivo: Avaliar o potencial hipolipemiante, antioxidante e sensorial de subprodutos do processamento do vinho e do suco. Métodos: Para avaliar a capacidade antioxidante in vi...

  11. A modified anxious behavior test for hamsters.

    Science.gov (United States)

    Shannonhouse, John L; York, Daniel C; Morgan, Caurnel

    2014-01-15

    Latency to feed in a novel environment assesses anxious behavior in rodents, but it is unclear whether it distinguishes anxiety from consumption or appetite. The anxiety-related feeding/exploration conflict (AFEC) test was used here to assess anxious behavior in Syrian hamsters for which increased cheek-pouching of food, but not overconsumption of it, reflects appetitive drive, and orexigenic stimuli do not increase consumption. The setup of the test prevented cheek-pouching. Latency to approach test food provided an additional control for non-emotional effects of treatments. Feed and approach latencies in the test cage were normalized to those in the home cage to factor out non-emotional effects. Feed latency and the feed latency ratio (test cage/home cage) were reduced by acute treatment with benzodiazepine, diazepam, or beta-adrenergic receptor antagonist, propranolol, or chronic treatment with norepinephrine reuptake inhibitor, desipramine. Reductions of feed latency and the feed latency ratio were not associated with hyperphagia, and these behaviors were unaltered by acute treatment with opioid receptor antagonist, naltrexone. Latency to approach food in the test cage, with and without normalization, was unaltered by these treatments. Finally, overnight fasting elevated feed latency without hyperphagia, and this effect was attenuated by chronic desipramine treatment. These results suggest that the AFEC test assesses anxious, but not appetitive or consummatory, behavior, and that its sensitivity increases with food deprivation of hamsters. Copyright © 2013. Published by Elsevier B.V.

  12. Activation of 5-HT2a receptors in the basolateral amygdala promotes defeat-induced anxiety and the acquisition of conditioned defeat in Syrian hamsters.

    Science.gov (United States)

    Clinard, Catherine T; Bader, Lauren R; Sullivan, Molly A; Cooper, Matthew A

    2015-03-01

    Conditioned defeat is a model in Syrian hamsters (Mesocricetus auratus) in which normal territorial aggression is replaced by increased submissive and defensive behavior following acute social defeat. The conditioned defeat response involves both a fear-related memory for a specific opponent as well as anxiety-like behavior indicated by avoidance of novel conspecifics. We have previously shown that systemic injection of a 5-HT2a receptor antagonist reduces the acquisition of conditioned defeat. Because neural activity in the basolateral amygdala (BLA) is critical for the acquisition of conditioned defeat and BLA 5-HT2a receptors can modulate anxiety but have a limited effect on emotional memories, we investigated whether 5-HT2a receptor modulation alters defeat-induced anxiety but not defeat-related memories. We injected the 5-HT2a receptor antagonist MDL 11,939 (0 mM, 1.7 mM or 17 mM) or the 5-HT2a receptor agonist TCB-2 (0 mM, 8 mM or 80 mM) into the BLA prior to social defeat. We found that injection of MDL 11,939 into the BLA impaired acquisition of the conditioned defeat response and blocked defeat-induced anxiety in the open field, but did not significantly impair avoidance of former opponents in the Y-maze. Furthermore, we found that injection of TCB-2 into the BLA increased the acquisition of conditioned defeat and increased anxiety-like behavior in the open field, but did not alter avoidance of former opponents. Our data suggest that 5-HT2a receptor signaling in the BLA is both necessary and sufficient for the development of conditioned defeat, likely via modulation of defeat-induced anxiety. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Kisspeptin and the seasonal control of reproduction in hamsters

    DEFF Research Database (Denmark)

    Simonneaux, Valérie; Ansel, Laura; Revel, Florent G

    2008-01-01

    -expressing neurons, which were recently shown to be implicated in the regulation of GnRH release. Hamsters are seasonal rodents which are sexually active in long photoperiod and quiescent in short photoperiod. The photoperiodic information is transmitted to the reproductive system by melatonin, a pineal...... in the arcuate nucleus of the Syrian hamster is lower in short photoperiod, when animals are sexually quiescent. Notably, intracerebroventricular infusion of Kiss1 gene product, kisspeptin, in hamsters kept in short photoperiod is able to override the inhibitory photoperiod and to reactivate sexual activity...

  14. Isolation and cross-sensitivity of X-ray-sensitive mutants of V79-4 hamster cells

    International Nuclear Information System (INIS)

    Jones, N.J.; Cox, R.; Thacker, J.

    1987-01-01

    The V79-4 Chinese hamster line was mutagenized and surviving clones screened for X-ray sensitivity using a replica microwell technique. One slightly sensitive clone and 3 clearly sensitive clones were isolated from approximately 5000 screened, and designated irs 1 to irs 4. The 3 more sensitive clones showed different responses to the genotoxic agents mitomycin C (MMC), ethyl methanesulphonate (EMS) and ultraviolet light (UV). irs 1 showed considerable sensitivity to all the agents tested, in the order MMC >> EMS > UV. irs 2 and irs 3 had similar sensitivities to EMS and to UV (EMS > UV) but irs 3 was more sensitive than irs 2 to MMC. None of these mutants is identical in phenotype to previously published mutants. (Auth.)

  15. Histaminergic regulation of seasonal metabolic rhythms in Siberian hamsters.

    Science.gov (United States)

    I'anson, Helen; Jethwa, Preeti H; Warner, Amy; Ebling, Francis J P

    2011-06-01

    We investigated whether histaminergic tone contributes to the seasonal catabolic state in Siberian hamsters by determining the effect of ablation of histaminergic neurons on food intake, metabolic rate and body weight. A ribosomal toxin (saporin) conjugated to orexin-B was infused into the ventral tuberomammillary region of the hypothalamus, since most histaminergic neurons express orexin receptors. This caused not only 75-80% loss of histaminergic neurons in the posterior hypothalamus, but also some loss of other orexin-receptor expressing cells e.g. MCH neurons. In the long-day anabolic state, lesions produced a transient post-surgical decrease in body weight, but the hamsters recovered and maintained constant body weight, whereas weight gradually increased in sham-lesioned hamsters. VO(2) in the dark phase was significantly higher in the lesioned hamsters compared to shams, and locomotor activity also tended to be higher. In a second study in short days, sham-treated hamsters showed the expected seasonal decrease in body weight, but weight remained constant in the lesioned hamsters, as in the long-day study. Lesioned hamsters consumed more during the early dark phase and less during the light phase due to an increase in the frequency of meals during the dark and decreased meal size during the light, and their cumulative food intake in their home cages was greater than in the control hamsters. In summary, ablation of orexin-responsive cells in the posterior hypothalamus blocks the short-day induced decline in body weight by preventing seasonal hypophagia, evidence consistent with the hypothesis that central histaminergic mechanisms contribute to long-term regulation of body weight. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Site of resistance to Necator americanus in hamsters.

    Science.gov (United States)

    Rajasekariah, G R; Deb, B N; Dhage, K R; Bose, S

    1985-12-01

    Resistance to the development of human hookworm, Necator americanus was examined in 3- to 6-week-old young adult hamsters. Only 3% of N. americanus infective third stage larvae (NaL3) reached maturity in the intestines of young adults as opposed to as many as 60% in 2-day-old baby hamsters. This seemingly effective resistance prevailing in young adults was investigated in some detail. The skin, the first site of contact for the invading NaL3, was bypassed during the infection process. Completely in vitro exsheathed NaL3 (ExNaL3) were used, and young adult hamsters were infected parenterally, by-passing the skin. Even after exsheathing the larvae artificially before infection and by-passing the skin, no improvement was seen in the development of N. americanus in the intestines of young adults. Higher infection doses also did not increase the worm burden. Some of the factors limiting the development of parasites in young adults were examined. N. americanus were monitored in lungs and intestines during various intervals after infection. Similar parasite burdens were apparent in lungs of baby as well as young adult hamsters. In the intestines, a significantly lower burden of N. americanus was seen during various intervals in young adults compared to the baby hamsters. Moreover, N. americanus were expelled soon after reaching the intestine. This comparative monitoring revealed the intestine as the seat of resistance against the establishment of N. americanus in young adult hamsters.

  17. Rice bran oil and oryzanol reduce plasma lipid and lipoprotein cholesterol concentrations and aortic cholesterol ester accumulation to a greater extent than ferulic acid in hypercholesterolemic hamsters.

    Science.gov (United States)

    Wilson, Thomas A; Nicolosi, Robert J; Woolfrey, Benjamin; Kritchevsky, David

    2007-02-01

    Our laboratory has reported that the hypolipidemic effect of rice bran oil (RBO) is not entirely explained by its fatty acid composition. Because RBO has a greater content of the unsaponifiables, which also lower cholesterol compared to most vegetable oils, we wanted to know whether oryzanol or ferulic acid, two major unsaponifiables in RBO, has a greater cholesterol-lowering activity. Forty-eight F(1)B Golden Syrian hamsters (Mesocricetus auratus) (BioBreeders, Watertown, MA) were group housed (three per cage) in cages with bedding in an air-conditioned facility maintained on a 12-h light/dark cycle. The hamsters were fed a chow-based hypercholesterolemic diet (HCD) containing 10% coconut oil and 0.1% cholesterol for 2 weeks, at which time they were bled after an overnight fast (16 h) and segregated into 4 groups of 12 with similar plasma cholesterol concentrations. Group 1 (control) continued on the HCD, group 2 was fed the HCD containing 10% RBO in place of coconut oil, group 3 was fed the HCD plus 0.5% ferulic acid and group 4 was fed the HCD plus 0.5% oryzanol for an additional 10 weeks. After 10 weeks on the diets, plasma total cholesterol (TC) and non-high-density lipoprotein cholesterol (HDL-C) (very low- and low-density lipoprotein) concentrations were significantly lower in the RBO (-64% and -70%, respectively), the ferulic acid (-22% and -24%, respectively) and the oryzanol (-70% and -77%, respectively) diets compared to control. Plasma TC and non-HDL-C concentrations were also significantly lower in the RBO (-53% and -61%, respectively) and oryzanol (-61% and -70%, respectively) diets compared to the ferulic acid. Compared to control and ferulic acid, plasma HDL-C concentrations were significantly higher in the RBO (10% and 20%, respectively) and oryzanol (13% and 24%, respectively) diets. The ferulic acid diet had significantly lower plasma HDL-C concentrations compared to the control (-9%). The RBO and oryzanol diets were significantly lower for

  18. Food restriction-induced changes in motivation differ with stages of the estrous cycle and are closely linked to RFamide-related peptide-3 but not kisspeptin in Syrian hamsters.

    Science.gov (United States)

    Benton, Noah A; Russo, Kim A; Brozek, Jeremy M; Andrews, Ryan J; Kim, Veronica J; Kriegsfeld, Lance J; Schneider, Jill E

    2017-06-15

    We tested the hypothesis that the effects of food restriction on behavioral motivation are mediated by one or both of the RFamide peptides, RFamide-related peptide-3 (RFRP-3) and kisspeptin (Kp) in female Syrian hamsters (Mesocricetus auratus). Female hamsters fed ad libitum and given a choice between food and adult male hamsters are highly motivated to visit males instead of food on all four days of the estrous cycle, but after 8days of mild food restriction (75% of ad libitum intake) they shift their preference toward food every day of the estrous cycle until the day of estrus, when they shift their preference back toward the males. In support of a role for RFRP-3 in these behavioral changes, the preference for food and the activation of RFRP-3-immunoreactive (Ir) cells in the dorsomedial hypothalamus (DMH) showed the same estrous cycle pattern in food-restricted females, but no association was observed between behavior and the activation of Kp cells in the hypothalamic arcuate nucleus or preoptic area. Next, we tested the hypothesis that food-restriction-induced activation of RFRP-3-Ir cells is modulated by high levels of ovarian steroids at the time of estrus. In support of this idea, on nonestrous days, mild food restriction increased activation of RFRP-3-Ir cells, but failed to do so on the day of estrus even though this level of food restriction did not significantly decrease circulating concentrations of estradiol or progesterone. Furthermore, in ovariectomized females, food-restriction-induced increases in activation of RFRP-3-Ir cells were blocked by systemic treatment with progesterone alone, estradiol plus progesterone, but not estradiol alone. Central infusion with RFRP-3 in ad libitum-fed females significantly decreased sexual motivation and produced significant increases in 90-minute food hoarding, in support of the hypothesis that elevated central levels of RFRP-3 are sufficient to create the shift in behavioral motivation in females fed ad libitum

  19. Hamster and Murine Models of Severe Destructive Lyme Arthritis

    Directory of Open Access Journals (Sweden)

    Erik Munson

    2012-01-01

    Full Text Available Arthritis is a frequent complication of infection in humans with Borrelia burgdorferi. Weeks to months following the onset of Lyme borreliosis, a histopathological reaction characteristic of synovitis including bone, joint, muscle, or tendon pain may occur. A subpopulation of patients may progress to a chronic, debilitating arthritis months to years after infection which has been classified as severe destructive Lyme arthritis. This arthritis involves focal bone erosion and destruction of articular cartilage. Hamsters and mice are animal models that have been utilized to study articular manifestations of Lyme borreliosis. Infection of immunocompetent LSH hamsters or C3H mice results in a transient synovitis. However, severe destructive Lyme arthritis can be induced by infecting irradiated hamsters or mice and immunocompetent Borrelia-vaccinated hamsters, mice, and interferon-gamma- (IFN-γ- deficient mice with viable B. burgdorferi. The hamster model of severe destructive Lyme arthritis facilitates easy assessment of Lyme borreliosis vaccine preparations for deleterious effects while murine models of severe destructive Lyme arthritis allow for investigation of mechanisms of immunopathology.

  20. Hamster and Murine Models of Severe Destructive Lyme Arthritis

    Science.gov (United States)

    Munson, Erik; Nardelli, Dean T.; Du Chateau, Brian K.; Callister, Steven M.; Schell, Ronald F.

    2012-01-01

    Arthritis is a frequent complication of infection in humans with Borrelia burgdorferi. Weeks to months following the onset of Lyme borreliosis, a histopathological reaction characteristic of synovitis including bone, joint, muscle, or tendon pain may occur. A subpopulation of patients may progress to a chronic, debilitating arthritis months to years after infection which has been classified as severe destructive Lyme arthritis. This arthritis involves focal bone erosion and destruction of articular cartilage. Hamsters and mice are animal models that have been utilized to study articular manifestations of Lyme borreliosis. Infection of immunocompetent LSH hamsters or C3H mice results in a transient synovitis. However, severe destructive Lyme arthritis can be induced by infecting irradiated hamsters or mice and immunocompetent Borrelia-vaccinated hamsters, mice, and interferon-gamma- (IFN-γ-) deficient mice with viable B. burgdorferi. The hamster model of severe destructive Lyme arthritis facilitates easy assessment of Lyme borreliosis vaccine preparations for deleterious effects while murine models of severe destructive Lyme arthritis allow for investigation of mechanisms of immunopathology. PMID:22461836

  1. Genitourinary changes in hamsters infected and reinfected with Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Cabrine-Santos Marlene

    2003-01-01

    Full Text Available Authors describe genitourinary changes in male hamsters infected and reinfected with Trypanosoma cruzi. Changes in genital organs have been described in human and in experimental chagasic infection. Genital dysfunctions in chronic chagasic patients affect ejaculation, libido and sexual potency, and testis biopsies may show arrested maturation of germ cells, oligozoospermia and azoospermia. Sixty-five male hamsters were inoculated and reinoculated with 2x10³ trypomastigotes of T. cruzi VIC strain, and 22 non-infected animals constituted the control group. Animals were necropsied and fragments from testis, epididymis, seminal vesicle and bladder were collected and stained with hematoxylin-eosin. Peroxidase anti-peroxidase procedure was utilized to detect tissue parasitism. T. cruzi nests were found in testis, epididymis and seminal vesicle of these hamsters. Such parasitism plays a role in the origin of genital lesions observed in humans and laboratory animals during chronic chagasic infection.

  2. Arnica Tincture Cures Cutaneous Leishmaniasis in Golden Hamsters

    Directory of Open Access Journals (Sweden)

    Sara M. Robledo

    2018-01-01

    Full Text Available In search for potential therapeutic alternatives to existing treatments for cutaneous Leishmaniasis, we have investigated the effect of Arnica tincture Ph. Eur. (a 70% hydroethanolic tincture prepared from flowerheads of Arnica montana L. on the lesions caused by infection with Leishmania braziliensis in a model with golden hamsters. The animals were treated topically with a daily single dose of the preparation for 28 days. Subsequently, the healing process was monitored by recording the lesion size in intervals of 15 days up to day 90. As a result, Arnica tincture fully cured three out of five hamsters while one animal showed an improvement and another one suffered from a relapse. This result was slightly better than that obtained with the positive control, meglumine antimonate, which cured two of five hamsters while the other three showed a relapse after 90 days. This result encourages us to further investigate the potential of Arnica tincture in the treatment of cutaneous Leishmaniasis.

  3. Hamster thecal cells express muscle characteristics

    International Nuclear Information System (INIS)

    Self, D.A.; Schroeder, P.C.; Gown, A.M.

    1988-01-01

    Contraction of the follicular wall about the time of ovulation appears to be a coordinated event; however, the cells that mediate it remain poorly studied. We examined the theca externa cells in the wall of hamster follicles for the presence of a functional actomyosin system, both in developing follicles and in culture. We used a monoclonal antibody (HHF35) that recognizes the alpha and gamma isoelectric variants of actin normally found in muscle, but not the beta variant associated with non-muscle sources, to evaluate large preovulatory follicles for actin content and composition. Antibody staining of sectioned ovaries showed intense circumferential reactivity in the outermost wall of developing follicles. Immunoblots from two-dimensional gels of theca externa lysates demonstrated the presence of the two muscle-specific isozymes of actin. Immunofluorescence of cultured follicular cells pulse-labeled with [3H] thymidine (for autoradiographic detection of DNA replication) revealed the presence, in many dividing cells, of actin filaments aligned primarily along the longitudinal axis of the cells. In cultures exposed to the calcium ionophore A23187 (10(-4) M) for varying periods (5 min to 1 h), contraction of many individual muscle-actin-positive cells was observed. Immunofluorescence of these cells, fixed immediately after ionophore-induced contraction, revealed compaction of the actin filaments. Our findings demonstrate that the cells of the theca externa contain muscle actins from an early stage and that these cells are capable of contraction even while proliferating in subconfluent cultures. They suggest that follicular growth may include a naturally occurring developmental sequence in which a contractile cell type proliferates in the differentiated state

  4. Secondhand smoke induces hepatic apoptosis and fibrosis in hamster fetus.

    Science.gov (United States)

    Huang, Chien-Wei; Horng, Chi-Ting; Huang, Chih-Yang; Cho, Ta-Hsiung; Tsai, Yi-Chang; Chen, Li-Jeng; Hsu, Tsai-Ching; Tzang, Bor-Show

    2016-09-01

    Secondhand smoke (SHS) is an important health issue worldwide. Inhaling SHS during pregnancy could cause abnormalities in the internal tissues of newborns, which may then impair fetal development and even cause severe intrauterine damage and perinatal death. However, the understanding of cytopathic mechanisms of SHS by maternal passive smoking on fetus liver during pregnancy is still limited. This study analyzed the effects of high-dose SHS (SHSH) on fetus liver using a maternal passive smoking animal model. Experiments showed that hepatic matrix metalloproteinase-9 activity and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling-positive cells were significantly increased in livers from fetuses of hamsters treated with SHSH. Similarly, expressions of both extrinsic and intrinsic apoptotic molecules were significantly higher in livers from fetuses of hamsters exposed to SHSH. Additionally, significantly increased inflammatory proteins, including transforming growth factor β, inducible nitric oxide synthase, and interleukin 1β, and fibrotic signaling molecules, including phosphorylated Smad2/3, SP1, and α-smooth muscle actin, were observed in the fetus livers from hamsters treated with SHSH. This study revealed that SHSH not only increased apoptosis through intrinsic and extrinsic pathways in the livers of fetuses from hamsters exposed to SHSH but also augmented hepatic fibrosis via Smad2/3 signaling. © The Author(s) 2015.

  5. Proliferation of epithelial cell forming hamster palate during prenatal period

    Czech Academy of Sciences Publication Activity Database

    Buchtová, M.; Tichý, F.; Matulová, Petra; Míšek, Ivan

    2003-01-01

    Roč. 76, č. 4 (2003), s. 254-255 [Moravský morfologický den/4./. 11.06.2003, Brno] R&D Projects: GA ČR GA304/02/0448; GA ČR GP304/01/P021 Institutional research plan: CEZ:AV0Z5045916 Keywords : hamster Subject RIV: ED - Physiology

  6. Het effect van hamsterbeheer op de overwintering bij hamsters

    NARCIS (Netherlands)

    Beek, van der M.; Ligtenberg, H.; Haye, la M.J.J.

    2006-01-01

    De afgelopen decennia is het aantal hamsters (Cricetus cricetus) in Nederland sterk afgenomen. Door onderzoek te verrichten naar de levenscyclus en naar de effecten van agrarisch beheer is getracht de afname te verklaren en oplossingen aan te dragen. In voorjaar 2006 is een verkennend onderzoek

  7. Humanizing recombinant glycoproteins from Chinese hamster ovary cells

    DEFF Research Database (Denmark)

    Hansen, Anders Holmgaard; Amann, Thomas; Kol, Stefan

    hamster ovary (CHO) cells are making a very heterogeneous mixture of NGlycans. We speculate that the CHO pattern of N-Glycans would affect half-life and/or efficacy of the glycoprotein in the bloodstream making it unsuitable for human intravenous use, whereas our humanized version would be identical...

  8. Bioavailability and disposition of solanine in rats and hamsters

    NARCIS (Netherlands)

    Groen K; Pereboom-de Fauw DPKH; Besamusca P; Beekhof PK; Speijers GJA; Derks HJGM

    1992-01-01

    The toxicokinetics of [3H]-alpha-solanine after oral (po) and intravenous (iv) administration in rats and hamsters were studied, in order to decide which is the most appropriate model in risk assessment studies. The iv dose was 54 mug/kg; the oral dose was 170 mug/kg. After iv administration, the

  9. Early postnatal development of the South African hamster ...

    African Journals Online (AJOL)

    The South African Hamster Mystromys albicaudatus has been bred in the laboratory of the. Medical Ecology Centre since 1941. It is of interest taxonomically in that it is the sole repre- sentative left in Africa of the subfamily Cricetinae (Davis 1962). It has been used in Medical. Research on poliomyelitis, benign ...

  10. Comparative susceptibility of vero and baby hamster kidney cell ...

    African Journals Online (AJOL)

    Comparative susceptibility of vero and baby hamster kidney cell lines to PPR virus. ... Bulletin of Animal Health and Production in Africa ... The inoculated BHK and Vero cells supported the growth of the virus with syncytia formation more commonly observed in the BHK cells while vacuolation and cell disintegration were ...

  11. Early Postnatal Development of the South African Hamster ...

    African Journals Online (AJOL)

    The South African Hamster Mystromys albicaudatus has been bred in the laboratory of the Medical Ecology Centre since 1941. It is of interest taxonomically in that it is the sole representative left in Africa of the subfamily Cricetinae (Davis 1962). It has been used in Medical Research on poliomyelitis, benign histoplasmosis, ...

  12. Seasonal aspects of sleep in the Djungarian hamster

    Directory of Open Access Journals (Sweden)

    Deboer Tom

    2003-05-01

    Full Text Available Abstract Background Changes in photoperiod and ambient temperature trigger seasonal adaptations in the physiology and behaviour of many species, including the Djungarian hamster. Exposure of the hamsters to a short photoperiod and low ambient temperature leads to a reduction of the polyphasic distribution of sleep and waking over the light and dark period. In contrast, a long photoperiod enhances the daily sleep-wake amplitude leading to a decline of slow-wave activity in NREM sleep within the light period. It is unknown whether these changes can be attributed specifically to photoperiod and/or ambient temperature, or whether endogenous components are contributing factors. The influence of endogenous factors was investigated by recording sleep in Djungarian hamsters invariably maintained at a low ambient temperature and fully adapted to a short photoperiod. The second recording was performed when they had returned to summer physiology, despite the maintenance of the 'winter' conditions. Results Clear winter-summer differences were seen in sleep distribution, while total sleep time was unchanged. A significantly higher light-dark cycle modulation in NREM sleep, REM sleep and waking was observed in hamsters in the summer physiological state compared to those in the winter state. Moreover, only in summer, REM sleep episodes were longer and waking bouts were shorter during the light period compared to the dark period. EEG power in the slow-wave range (0.75–4.0 Hz in both NREM sleep and REM sleep was higher in animals in the summer physiological state than in those in the 'winter' state. In winter SWA in NREM sleep was evenly distributed over the 24 h, while in summer it decreased during the light period and increased during the dark period. Conclusion Endogenous changes in the organism underlie the differences in sleep-wake redistribution we have observed previously in hamsters recorded in a short and long photoperiod.

  13. Modeling the dual pacemaker system of the tau mutant hamster.

    Science.gov (United States)

    Oda, G A; Menaker, M; Friesen, W O

    2000-06-01

    Circadian pacemakers in many animals are compound. In rodents, a two-oscillator model of the pacemaker composed of an evening (E) and a morning (M) oscillator has been proposed based on the phenomenon of "splitting" and bimodal activity peaks. The authors describe computer simulations of the pacemaker in tau mutant hamsters viewed as a system of mutually coupled E and M oscillators. These mutant animals exhibit normal type 1 PRCs when released into DD but make a transition to a type 0 PRC when held for many weeks in DD. The two-oscillator model describes particularly well some recent behavioral experiments on these hamsters. The authors sought to determine the relationships between oscillator amplitude, period, PRC, and activity duration through computer simulations. Two complementary approaches proved useful for analyzing weakly coupled oscillator systems. The authors adopted a "distinct oscillators" view when considering the component E and M oscillators and a "system" view when considering the system as a whole. For strongly coupled systems, only the system view is appropriate. The simulations lead the authors to two primary conjectures: (1) the total amplitude of the pacemaker system in tau mutant hamsters is less than in the wild-type animals, and (2) the coupling between the unit E and M oscillators is weakened during continuous exposure of hamsters to DD. As coupling strength decreases, activity duration (alpha) increases due to a greater phase difference between E and M. At the same time, the total amplitude of the system decreases, causing an increase in observable PRC amplitudes. Reduced coupling also increases the relative autonomy of the unit oscillators. The relatively autonomous phase shifts of E and M oscillators can account for both immediate compression and expansion of activity bands in tau mutant and wild-type hamsters subjected to light pulses.

  14. Rapid induction of glomerular lipidosis in APA hamsters by streptozotocin.

    Science.gov (United States)

    Han, J. S.; Sugawara, Y.; Doi, K.

    1992-01-01

    The pathology of male Syrian hamsters of APA strain which were injected intraperitoneally with 40 mg/kg body weight of streptozotocin (SZ) at 2 months of age was examined. It showed long-lasting prominent hyperglycaemia and hyperlipidaemia with glucosuria and the development of glomerular lipidosis from 1 month after SZ-injection (1 MAI). Glomerular lesions were restricted to the juxtamedullary cortex at 1 MAI and then extended to the subcapsular cortex. At 3 MAI, glomerular lesions were characterized by focal segmental glomerulosclerosis showing segmental expansion of the mesangial area due to an increase of basement membrane-like material and mesangial cells with lipid droplets and foam cells. SZ-induced diabetic APA hamsters will be a useful model for the investigation of glomerular lipidosis and focal segmental glomerulosclerosis. Images Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:1533531

  15. Cystolithiasis in a Syrian hamster: a different outcome

    Directory of Open Access Journals (Sweden)

    D. Petrini

    2016-08-01

    Full Text Available A 14-month-old intact male Syrian hamster was admitted for lethargy and hematuria. A total body radiographic image and abdominal ultrasonography showed the presence of a vesical calculus. During cystotomy, a sterile urine sample was obtained and sent to the diagnostic laboratory along with the urolith for analysis. Urine culture was found negative for bacterial growth, and the urolith was identified as a calcium-oxalate stone. Diet supplementation with palmitoylethanolamide, glucosamine and hesperidin was adopted the day after discharge. One year follow up revealed no presence of vesical calculi. Although this is the report of a single clinical case, this outcome differs from the results reported in the literature characterized by recurrences after few months. Considering the positive outcome and the beneficial properties of palmitoylethanolamide, glucosamine, and hesperidin, these nutritional elements in Syrian hamsters, are recommended to reduce recurrence after surgical treatment of urolithiasis.

  16. Radioprotective effect of catecholamines on the cultured Chinese hamster fibroblasts

    International Nuclear Information System (INIS)

    Chirkov, Yu.Yu.; Malatsidze, M.A.; Sobolev, A.S.

    1985-01-01

    On cultivated in vitro Chinese hamster fibroblasts radioprotective properties of adrenaline, noradrenaline and isoproterenol in different concentrations are studied. Isoproterenol radiopreventive effect is clearly manifested with its concentration being 1x10 -8 M; adrenaline and noradrenaline are efficient in higher concentrations. Propranolol, blocking β-adrenergic receptors, completely presents radioprotective effect of catecholamines on the cells. β-adrenergic mechanism of catecholamine radioprotective effect on Mammalia cells is discussed

  17. Autoradiographic images in the hamster cheek pouch oral cancer model

    International Nuclear Information System (INIS)

    Portu, A.; Molinari, A.J.; Schwint, A.; Saint Martin, G.; Thorp, S.; Pozzi, E.C.C.; Curotto, P.

    2013-01-01

    The aim of this work is to summarize the autoradiographic study performed to samples from different protocols of the hamster cheek pouch oral cancer model. The qualitative analysis of histological and autoradiographic images, together with the determination of the boron concentration in the different structures of tumor, premalignant tissue and normal tissue contributed to the knowledge of the microdistribution of boron compounds. Besides, the study led to the optimization of the autoradiography technique applied to BNCT (Boron Neutron Capture Therapy). (author)

  18. Hibernation, stress, intestinal functions, and catecholoamine turnover rate in hamsters and gerbils

    Science.gov (United States)

    Musacchia, X. J.

    1973-01-01

    Bioenergetic studies on hamsters during depressed metabolic states are reported. External support of blood glucose extended the survival times of hibernating animals. Radioresistance increased in hibernating as well as in hypothermic hamsters. Marked changes in hamster catecholamine turnover rates were observed during acclimatization to high temperature stress. High radioresistance levels of the gerbil gastrointestinal system were attributed in part to the ability of the gut to maintain functional integrity.

  19. Isolation of two chloroethylnitrosourea-sensitive Chinese hamster cell lines

    International Nuclear Information System (INIS)

    Hata, H.; Numata, M.; Tohda, H.; Yasui, A.; Oikawa, A.

    1991-01-01

    1-[(4-Amino-2-methylpyrimidin-5-yl)methyl]-3-(2-chloroethyl)-3- nitrosourea hydrochloride (ACNU), a cancer chemotherapeutic bifunctional alkylating agent, causes chloroethylation of DNA and subsequent DNA strand cross-linking through an ethylene bridge. We isolated and characterized two ACNU-sensitive mutants from mutagenized Chinese hamster ovary cells and found them to be new drug-sensitive recessive Chinese hamster mutants. Both mutants were sensitive to various monofunctional alkylating agents in a way similar to that of the parental cell lines CHO9. One mutant (UVS1) was cross-sensitive to UV and complemented the UV sensitivity of all Chinese hamster cell lines of 7 established complementation groups. Since UV-induced unscheduled DNA synthesis was very low, a new locus related to excision repair is thought to be defective in this cell line. Another ACNU-sensitive mutant, CNU1, was slightly more sensitive to UV than the parent cell line. CNU1 was cross-sensitive to 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea and slightly more sensitive to mitomycin C. No increased accumulation of ACNU and a low level of UV-induced unscheduled DNA synthesis in this cell as compared with the parental cell line suggest that there is abnormality in a repair response of this mutant cell to some types of DNA cross-links

  20. Female-biased anorexia and anxiety in the Syrian hamster.

    Science.gov (United States)

    Shannonhouse, John L; Fong, Li An; Clossen, Bryan L; Hairgrove, Ross E; York, Daniel C; Walker, Benjamin B; Hercules, Gregory W; Mertesdorf, Lauren M; Patel, Margi; Morgan, Caurnel

    2014-06-22

    Anorexia and anxiety cause significant mortality and disability with female biases and frequent comorbidity after puberty, but the scarcity of suitable animal models impedes understanding of their biological underpinnings. It is reported here that in adult or weanling Syrian hamsters, relative to social housing (SH), social separation (SS) induced anorexia characterized as hypophagia, weight loss, reduced adiposity, and hypermetabolism. Following anorexia, SS increased reluctance to feed, and thigmotaxis, in anxiogenic environments. Importantly, anorexia and anxiety were induced post-puberty with female biases. SS also reduced hypothalamic corticotrophin-releasing factor mRNA and serum corticosteroid levels assessed by RT-PCR and RIA, respectively. Consistent with the view that sex differences in adrenal suppression contributed to female biases in anorexia and anxiety by disinhibiting neuroimmune activity, SS elevated hypothalamic interleukin-6 and toll-like receptor 4 mRNA levels. Although corticosteroids were highest during SH, they were within the physiological range and associated with juvenile-like growth of white adipose, bone, and skeletal muscle. These results suggest that hamsters exhibit plasticity in bioenergetic and emotional phenotypes across puberty without an increase in stress responsiveness. Thus, social separation of hamsters provides a model of sex differences in anorexia and anxiety during adulthood and their pathogeneses during adolescence. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Melanin content of hamster tissues, human tissues, and various melanomas

    Energy Technology Data Exchange (ETDEWEB)

    Watts, K.P.; Fairchild, R.G.; Slatkin, D.N.; Greenberg, D.; Packer, S.; Atkins, H.L.; Hannon, S.J.

    1981-02-01

    Melanin content (percentage by weight) was determined in both pigmented and nonpigmented tissues of Syrian golden hamsters bearing Greene melanoma. Melanin content was also measured in various other melanoma models (B-16 in C57 mice, Harding-Passey in BALB/c mice, and KHDD in C3H mice) and in nine human melanomas, as well as in selected normal tissues. The purpose was to evaluate the possible efficacy of chlorpromazine, which is known to bind to melanin, as a vehicle for boron transport in neutron capture therapy. Successful therapy would depend upon selective uptake and absolute concentration of borated compounds in tumors; these parameters will in turn depend upon melanin concentration in melanomas and nonpigmented ''background'' tissues. Hamster whole eyes, hamster melanomas, and other well-pigmented animal melanomas were found to contain 0.3 to 0.8% melanin by weight, whereas human melanomas varied from 0.1 to 0.9% (average, 0.35%). Other tissues, with the exception of skin, were lower in content by a factor of greater than or equal to30. Melanin pigment was extracted from tissues, and the melanin content was determined spectrophotometrically. Measurements were found to be sensitive to the presence of other proteins. Previous procedures for isolating and quantifying melanin often neglected the importance of removing proteins and other interfering nonmelanic substances.

  2. Effects of hyperthermia on the hamster immune system

    International Nuclear Information System (INIS)

    Gangavalli, R.; Cain, C.A.; Tompkins, W.A.F.

    1984-01-01

    In previous studies, the authors have shown that hyperthermia can enhance antibody-complement chytotoxicity of hamster and human tumor cells. Moreover, whole body microwave exposure of hamsters resulted in activation of peritoneal macrophages to a viricidal state and transient suppression of natural killer (NK) cell activity. In this study, the authors compare the effects of whole body heating by microwaves or by an environmental chamber (hot air) on the hamster immune system. Microwave exposure (25mW/cm/sup 2/; 1 hr) caused viricidal activation of peritoneal macrophages which resulted in restriction of vaccinia and vesicular stomatitis virs (VSV) growth. However, heating in an environmental chamber (41 0 C; 1 hr) did not activate macrophages to a viricidal state. Both microwave and hot air hyperthermia caused significant augmentation of antibody producing spleen cell response to sheep red blood cells (SRBC), using the Jerne hymolytic plaque assay, four days post exposure and immunization with SRBC. Natural killer spleen cell cytotoxicity was suppressed by microwave and hot air hyperthermia showing that NK lymphocytes are extremely sensitive to changes in temperature. These alterations in cellular immune response due to hyperthermia could be of significance in treatment of tumors and viral infections

  3. Prevalence of intestinal parasites in hamsters and rabbits in some pet shops of Turkey.

    Science.gov (United States)

    Sürsal, Neslihan; Gökpinar, Sami; Yildiz, Kader

    2014-06-01

    In this study, we aimed to determine the parasite species carried by hamsters and rabbits purchased from some commercial pet shops in Turkey. For this purpose, the fecal samples of clinically healthy Syrian hamsters, dwarf hamsters, and crossbred rabbits were collected from 22 pet shops randomly selected in Ankara and Kirikkale provinces, located in Central Anatolia Region of Turkey. The fecal samples were examined with centrifuge flotation technique using saturated salt solution. Parasitic infection rate was 57.5% in dwarf hamsters, 54.9% in Syrian hamsters, and 56.3% in crossbreed rabbits. Trichurid eggs were the most prevalent parasite in the feces of Syrians hamsters (28.1%). The other parasites of Syrian hamsters were as follows: Eimeria spp. oocysts (15.4%) and the eggs of H. nana (11.2%), Syphacia spp. (11%). and Aspiculuris spp. (5.6 %). Only trichurid eggs were observed in the fecal samples of dwarf hamsters (51.5%). Oocysts of Eimeria spp. (52.7%) and the eggs of P. ambiguus (3.6%) were detected in the feces of rabbits. Within the scope of this study, the detection of H. nana eggs, a zoonotic parasite, in the feces of Syrian hamster was quite remarkable for public health.

  4. The presence of opioidergic pinealocytes in the pineal gland of the European hamster (Cricetus cricetus): an immunocytochemical study

    DEFF Research Database (Denmark)

    Coto-Montes, A.; Masson-Pévet, M.; Pévet, P.

    1994-01-01

    Neurobiologi, pineal gland, leu-enkephalin, Met-enkephalin, synaptic contacts, paracrine regulation, European hamster, cricetus cricetus (rodents)......Neurobiologi, pineal gland, leu-enkephalin, Met-enkephalin, synaptic contacts, paracrine regulation, European hamster, cricetus cricetus (rodents)...

  5. Andes Virus M Genome Segment is Not Sufficient to Confer the Virulence Associated With Andres Virus in Syrian Hamsters

    National Research Council Canada - National Science Library

    McElroy, A

    2004-01-01

    ...) in North and South America, respectively. Although ANDV causes a lethal HPS-like disease in hamsters, SNV, and all other HPS-associated hantaviruses that have been tested, cause asymptomatic infections of laboratory animals, including hamsters...

  6. Transplantation of hamster lung lesions induced by 239PuO2 or benz(a)pyrene

    International Nuclear Information System (INIS)

    McDonald, K.E.; Sanders, C.L.

    1980-01-01

    None(0%) of 1000 recipients of lung lesions for 239 PuO 2 -exposed hamsters that were transplanted into other hamsters' cheek pouches, developed tumors, whereas 90% of transplants from benz(a)pyrene-induced lung lesions were malignant

  7. Effect of prenatal and postnatal photoperiod on spermatogenic development in the Djungarian hamster (Phodopus sungorus sungorus)

    NARCIS (Netherlands)

    van Haaster, L. H.; van Eerdenburg, F. J.; de rooij, D. G.

    1993-01-01

    The effect of the pre- and postnatal daylength on the start of spermatogenesis and further testicular development from day 4 up to day 127 was investigated in Djungarian hamsters. Hamsters were either gestated under long (16 h light:8 h dark) photoperiod and reared under long or short (4 h light:20

  8. Spermatogenesis is accelerated in the immature Djungarian and Chinese hamster and rat

    NARCIS (Netherlands)

    van Haaster, L. H.; de rooij, D. G.

    1993-01-01

    The rate of progression of spermatogenesis was studied in immature Djungarian and Chinese hamsters and Wistar rats by scoring the most advanced cell types present at various ages after birth. From 15 days of age onward, the most advanced cell types in the Djungarian hamsters were formed at a rate

  9. The hamster cheek pouch: an immunologically privileged site suitable to the study of granulomatous infections A bolsa jugal do hamster: um local imunologicamente privilegiado, apropriado para o estudo das ¡nfecções granulomatosas

    Directory of Open Access Journals (Sweden)

    M. S. P. de Arruda

    1995-08-01

    Full Text Available The hamster check pouch is an invagination of oral mucosa, characterized histologically as skin-like. In this paper we describe anatomical, histological and embriological features of the pouch and coment on the pouch as an immunologically privileged site since it lacks lymphatic drainage and has few Langerhans cells. We present the review from literature and our observations after inoculation in the pouch of mycobacteriae (BCG, Mycobacterium tuberculosis and Mycobacterium leprae and a fungus (Paracoccidioides brasiliensis. Lesions in the pouch were granulomatous but smaller and long lasting; even granulomatous, the reaction was inefficient to control the proliferation of agents compared with inoculation in other sites, except for BCG. Appearance of immunity was also delayed or absent and, when it was detected, a sharp decrease in number of agents in pouch lesions was observed. These observations make the pouch an interesting site for the study of the role of immune system in infeccious diseases and in granuloma formation.A bolsa jugal do hamster (BJH é uma invaginação da mucosa oral, caracterizada histologicamente como semelhante a pele. Nesse estudo nós descrevemos algumas de suas características anatômicas, histológicas e embriológicas e comentamos sobre sua propriedade como local imunologicamente privilegiado, considerando a ausência de drenagem linfática e o reduzido número de células de Langerhans. Apresentamos também os resultados obtidos quando da inoculação de micobacterias (BCG, Mycobacterium tuberculosis e Mycobacterium leprae e do fungo Paracoccidioides brasiliensis na bolsa jugal. Comparada com as lesões provocadas em outras localizações e, à exceção do BCG, as lesões induzidas na bolsa são menores e de maior duração e, mesmo quando granulomatosas, incapazes de controlar a multiplicação do agente; nos casos em que houve o desenvolvimento da resposta imune, ele se fez tardiamente e foi acompanhado pela redu

  10. [The annual cycle in the Djungarian Hamster Phodopus sungorus Pallas].

    Science.gov (United States)

    Figala, J; Hoffmann, K; Goldau, G

    1973-06-01

    Seasonal variations in several functions were observed in a strain of Phodopus s. sungorus bred and kept in the laboratory at Erling-Andechs (47° 58'N, 11° 11'E) under natural illumination: 1. During their first winter most hamsters changed into a whitish winter coat (Figs. 2, 5, and 14). The change in fur coloration is described (Fig. 1). In most animals molt into the winter coat started in October or November, and was completed in December. Molt into the summer coat started in January or February, and was completed in March or early April. Hamsters kept at outdoor temperatures started molt into winter pelt earlier, and finished molt into summer pelt later, than animals kept indoors (Figs. 3 and 4). Winter coloration was more extreme in animals kept at outdoor temperatures. 2. Molt into the winter coat was induced in summer by exposing hamsters to short photoperiods (Fig. 6). However, these animals spontaneously changed back into summer fur while remaining under short-day conditions. 3. The animals had a marked annual cycle in body weight with maximum weight in July and August, and minimum weight in December and January, while they were in winter pelage (Figs. 7 and 8). 4. Reproduction was observed only between February and November (Fig. 9). Young were born within 18 days (2 cases) or 19 days (27 cases) after the breeding pairs were established. Mean litter size was 5 (range 1-9) (Fig. 10). Average litter size was smaller in the first litter of a ♀ than in the second, but was smaller again in subsequent litters (Fig. 11). 5. Growth curves of young hamsters were compared with data from the literature (Fig. 12). In the mean ♂ ♂ were heavier than ♀ ♀ (Table 1). 6. The majority of ♂ ♂ showed testis involution during the first winter. The weight of winter testes was about 1/9th that of summer testes (Fig. 13). The cauda epididymidis contained no spermatozoa in winter animals, and many in summer animals. 7. Daily torpor was observed in many animals, but

  11. Effect of deuterium on the circadian period and metabolism in wild-type and tau mutant Syrian hamsters

    NARCIS (Netherlands)

    Oklejewicz, M; Hut, RA; Daan, S

    2000-01-01

    Homozygous tau mutant Syrian hamsters (tau-/-) have a free-running circadian period (tau) around 20 h and a proportionally higher metabolic rate compared with wild-type hamsters (tau+/+) with a period of circa 24 h. In this study, we applied deuterium oxide (D2O) to hamsters to test whether

  12. Enhancement of postreplication repair in Chinese hamster cells

    International Nuclear Information System (INIS)

    D'Ambrosio, S.M.; Setlow, R.B.

    1976-01-01

    Alkaline sedimentation profiles of pulse-labeled DNA from Chinese hamster cells showed that DNA from cells treated with N-acetoxy-acetylaminofluorene or ultraviolet radiation was made in segments smaller than those from untreated cells. Cells treated with a small dose (2.5 μM) of N-acetoxy-acetylaminofluorene or(2.5 J . m -2 ) 254-nm radiation, several hours before a larger dose (7 to 10 μM) of N-acetoxy-acetylaminofluorene or 5.0 J . m -2 of 254-nm radiation, also synthesized small DNA after the second dose. However, the rate at which this small DNA was joined together into parental size was appreciably greater than in absence of the small dose. This enhancement of postreplication repair (as a result of the initial small dose) was not observed when cells were incubated with cycloheximide between the two treatments. The results suggest that N-acetoxy-acetylaminofluorene and ultraviolet-damaged DNA from Chinese hamster cells are repaired by similar postreplicative mechanisms that require de novo protein synthesis for enhancement

  13. Differentiation of hamster liver oval cell following Clonorchis sinensis infection.

    Science.gov (United States)

    Yoon, B I; Jung, S Y; Hur, K; Lee, J H; Joo, K H; Lee, Y S; Kim, D Y

    2000-12-01

    Oval cells which appear in the liver after hepatic injuries are suspected to be progenitor cells for both hepatocytes and bile duct cells. Oval cell isolated from the livers of the hamsters treated with diethylnitrosamine and 2-acetylaminofluorene and infected with Clonorchis sinensis (CS). cultured for 2 weeks and evaluated for differentiation and plasticity by electron microscopy and immunohistochemistry. In the CS-uninfected group, glycogen granules and peroxisomes were noted in the cells that were cultured for 2 weeks. Starting at 1 week postculture, immunoreactivity of the cells to cytokeratin 19 markedly decreased but that to albumin and alpha-fetoprotein gradually increased. This means that oval cells isolated from hamsters that were not infected with CS differentiated toward hepatocyte lineage. However, in the CS-infected group, cultured cells contained numerous rough endoplasmic reticulum and showed immunoreactivity that was generally in reverse to that of CS-uninfected group, meaning that cells isolated following CS infection were primed by CS and differentiated toward bile duct cell lineage. The results of this study suggested that oval cells are indeed bipolar progenitor cells for hepatocytes and bile duct cells and can differentiate toward either lineage depending upon the priming factor.

  14. Expression of thioredoxin during progression of hamster and human cholangiocarcinoma.

    Science.gov (United States)

    Yoon, Byung-Il; Kim, Yeong-Hun; Yi, Jung-Yeon; Kang, Min-Soo; Jang, Ja-June; Joo, Kyoung-Hwan; Kim, Yongbaek; McHugh Law, J; Kim, Dae-Yong

    2010-01-01

    Thioredoxin (Trx) is a multifunctional redox protein that has growth-promoting and anti-apoptotic effects on cells and protects cells from endogenous and exogenous free radicals. Recently, altered expression of Trx has been reported in various cancers. In the present study, we investigated altered expression of Trx at the precancerous and carcinogenic phases during cholangiocarcinogenesis in a hamster cholangiocarcinoma (ChC) model, using semiquantitative immunohistochemical and Western blot analyses. Moreover, to determine if the results correlated well with those in human ChCs, we carried out a comparative immunohistochemical study for Trx in tissue-arrayed human ChCs with different grades of tumor cell differentiation. Trx was found highly expressed in the cytoplasm of dysplastic bile ducts with highly abnormal growth patterns and ChCs irrespective of tumor type or tumor cell differentiation. Overexpression of Trx at the precancerous and carcinogenic phases was further supported by significant elevation of Trx protein in Western blotting. The results from the hamster ChCs were in good agreement with those from human ChCs. Our results strongly suggested that the redox regulatory function of Trx plays an important role in bile duct cell transformation and tumor progression during cholangiocarcinogenesis.

  15. Role of luteinizing hormone in luteotropic complex of pregnant hamster

    International Nuclear Information System (INIS)

    Tamura, H.; Greenwald, G.S.

    1987-01-01

    Hamsters were hypophysectomized on day 4 of pregnancy and injected subcutaneously on days 4-7 with various combinations of 200 μg prolactin (Prl), 10 μg follicle-stimulating hormone (FSH), and 20 μg luteinizing hormone (LH) in polyvinylpyrrolidone (PVP) to decrease its rate of absorption or in saline. End points for luteal function on day 8 were maintenance of pregnancy, serum progesterone (P 4 ), luteal weight, and luteal binding for human chorionic gonadotropin, FSH, and Prl. After hypophysectomy, a drastic decline occurred in all parameters including an 89% decrease in luteal weight. Injection of Prl did not maintain pregnancy nor serum P 4 but partially maintained luteal weight and human chorionic gonadotropin binding sites per corpus luteum. The minimal luteotropic complex of Prl and FSH was effective in maintaining pregnancy and significantly increased serum P 4 and Prl and FSH receptors but not to control levels. Thus, the luteotropic activity of LH was only demonstrable when it was injected in a long-acting form; when delivered as a bolus, LH (saline) was luteolytic. P 4 and estradiol were measured by radioimmunoassay. Radioiodinated gonadotropins were prepared. The percentage of tracer reacting with an excess of receptor were 51% of 125 I-FSH and 45.9% of 125 I-hCG using whole homogenates of hamster ovaries

  16. Determination of elements in blood of golden hamster by NAA

    International Nuclear Information System (INIS)

    Aguiar, Rodrigo Oliveira de

    2009-01-01

    In the present study Neutron Activation Analysis technique has been used to determine, simultaneously, some element concentrations of clinical relevance in whole blood samples of golden hamster. The normal range for Br, Ca, Cl K, Mg, Na and S considering 2 σ (Two Standard deviations) was 0.011 0.047 gL -1 (Br); 0.11 0.35 gL -1 (Ca); 2.11 3.75 gL -1 (Cl); 1.35 2.79 gL -1 (K), 0.026 0.090 gL -1 (Mg), 1.03 2.51 gL -1 (Na) e 0.97 2.01 gL -1 (S). The knowledge of these limits became possible to perform clinical investigation in this animal model using whole blood. The comparison with the results from human being whole blood estimation (Hamster and human) became possible to check the similarities or physiologic differences, an important data for animal experimentation. (author)

  17. Changes of spontaneous parthenogenetic activation and development potential of golden hamster oocytes during the aging process.

    Science.gov (United States)

    Jiang, Han; Wang, Ce; Guan, Jiyu; Wang, Lingyan; Li, Ziyi

    2015-01-01

    The golden hamster is an excellent animal experimental model for oocyte research. The hamster oocytes are very useful in clinical examination of human spermatozoan activity. Non-fertile oocytes can lead to time-dependent processes of aging, which will affect the results of human spermatozoa examination. As a consequence there is a need to investigate the aging and anti-aging processes of golden hamster oocytes. In order to study the aging processes and parthenogenetic activation of golden hamster oocytes, in vivo oocytes, oocytes cultured with or without cumulus cells, and oocytes treated with Trichostatin A (TSA) or caffeine were collected and investigated. We found that: (1) spontaneous parthenogenetic activation, developmental potential (cleavage rate), and zona pellucida (ZP) hardening undergo age-dependent changes in in vivo, in vitro, and after TSA or caffeine treatment; (2) in vivo, oocytes became spontaneously parthenogenetic 25 h post-hCG treatment; (3) in vitro, cumulus cells did not significantly increase the parthenogenetic activation rate of cultured hamster oocytes; and (4) TSA or caffeine could delay spontaneous oocyte parthenogenetic activation and the aging processes by at least 5h, but also accelerated the hardening of the ZP. These results define the conditions for the aging and anti-aging processes in golden hamster oocytes. TSA and caffeine play roles in controlling spontaneous activation, which could facilitate the storage and use of golden hamster oocytes for studying processes relevant to human reproduction. Copyright © 2014 Elsevier GmbH. All rights reserved.

  18. Postimplantation Whole Embryo Culture Assay for Hamsters: An Alternative to Rat and Mouse

    Directory of Open Access Journals (Sweden)

    Bogdan Wlodarczyk

    2001-01-01

    Full Text Available Postimplantation whole embryo culture (WEC assay for rats and mice has been well established and introduced to many laboratories. Recently WEC technique for rabbits has been developed; however, information on culture of other species is very limited. Knowing the usefulness of hamsters in classical embryotoxicology, we reasoned that hamster WEC could be an alternative model for the most frequently used rat and mouse WEC. Previously we have optimized culture conditions for postimplantation hamster embryos. The aim of this study was to test the susceptibility of hamster embryos cultured in vitro to embryotoxic compounds and to compare our results with those reported by others on rat or mouse embryo culture. For that purpose we choose three known embryotoxic compounds�valproic acid, cadmium chloride, and diethylstilbestrol�and tested them using a postimplantation hamster whole embryo culture assay. Hamster embryos were cultured from 7.5 days gestation for 24 h in a medium consisting of 35% hamster serum and 65% synthetic culture medium (Iscove�s or McCoy 5A. At the end of the culture period, the embryos were examined morphologically, measured with the aid of a computer image analysis system, and total protein content was assessed. All three compounds exhibited dose-related embryotoxic and teratogenic effects in hamster embryos. The malformations observed were similar to those reported on rat and mouse embryos. Comparison of the results with data reported by other authors indicates that hamster embryos cultured in vitromight be more susceptible to embryotoxic stimuli than rat and mouse embryos.

  19. Chinese hamster genome database: an online resource for the CHO community at www.CHOgenome.org.

    Science.gov (United States)

    Hammond, Stephanie; Kaplarevic, Mihailo; Borth, Nicole; Betenbaugh, Michael J; Lee, Kelvin H

    2012-06-01

    The Chinese hamster genome database (http://www.chogenome.org/) is an online resource for the Chinese hamster (Cricetulus griseus) and Chinese hamster ovary (CHO) cell communities. CHO cells are important for biomedical research and are widely used in industry for the production of biopharmaceuticals. The genome of the CHO-K1 cell line was recently sequenced and the CHO community has developed an online resource to facilitate accessibility of the genomic data and the development of genomic tools. Copyright © 2011 Wiley Periodicals, Inc.

  20. Mitotic spindle proteomics in Chinese hamster ovary cells.

    Directory of Open Access Journals (Sweden)

    Mary Kate Bonner

    Full Text Available Mitosis is a fundamental process in the development of all organisms. The mitotic spindle guides the cell through mitosis as it mediates the segregation of chromosomes, the orientation of the cleavage furrow, and the progression of cell division. Birth defects and tissue-specific cancers often result from abnormalities in mitotic events. Here, we report a proteomic study of the mitotic spindle from Chinese Hamster Ovary (CHO cells. Four different isolations of metaphase spindles were subjected to Multi-dimensional Protein Identification Technology (MudPIT analysis and tandem mass spectrometry. We identified 1155 proteins and used Gene Ontology (GO analysis to categorize proteins into cellular component groups. We then compared our data to the previously published CHO midbody proteome and identified proteins that are unique to the CHO spindle. Our data represent the first mitotic spindle proteome in CHO cells, which augments the list of mitotic spindle components from mammalian cells.

  1. Estudios inmunologicos en hamsters (Cricetus auratus infectados con Schistosoma mansoni

    Directory of Open Access Journals (Sweden)

    Eduardo Monge

    1986-08-01

    Full Text Available Los resultados de este trabajo muestran que el hamster (Cricetus auratus puede ser utilizado como un modelo experimental para estudios inmunológicos en la infección por Schistosoma mansoni. Los datos obtenidos, relativos a inmunidad concomitante, producción de anticuerpo letal e inmunosupresión se asemejan a los conseguidos en otros modelos experimentales ya establecidos. Estas observaciones indican que el hámster, además de ser un hospedero satisfactorio para el mantenimiento del parásito en el laboratorio, puede ser considerado como un modelo experimental alterno cuyo crecimiento y mantenimiento son relativamente simples y además es un animal de fácil manejo.

  2. Chinese hamster pleiotropic multidrug-resistant cells are not radioresistant

    International Nuclear Information System (INIS)

    Mitchell, J.B.; Gamson, J.; Russo, A.; Friedman, N.; DeGraff, W.; Carmichael, J.; Glatstein, E.

    1988-01-01

    The inherent cellular radiosensitivity of a Chinese hamster ovary pleiotropic cell line that is multidrug resistant (CHRC5) was compared to that of its parental cell line (AuxB1). Radiation survival curve parameters n and D0 were 4.5 and 1.1 Gy, respectively, for the CHRC5 line and 5.0 and 1.2 Gy, respectively, for the parental line. Thus, the inherent radiosensitivity of the two lines was similar even though key intracellular free radical scavenging and detoxifying systems employing glutathione, glutathione transferase, and catalase produced enzyme levels that were 2.0-, 1.9-, and 1.9-fold higher, respectively, in the drug-resistant cell line. Glutathione depletion by buthionine sulfoximine resulted in the same extent of aerobic radiosensitization in both lines (approximately 10%). Incorporation of iododeoxyuridine into cellular DNA sensitized both cell lines to radiation. These studies indicate that pleiotropic drug resistance does not necessarily confer radiation resistance

  3. Photoperiod Regulates vgf-Derived Peptide Processing in Siberian Hamsters.

    Directory of Open Access Journals (Sweden)

    Barbara Noli

    Full Text Available VGF mRNA is induced in specific hypothalamic areas of the Siberian hamster upon exposure to short photoperiods, which is associated with a seasonal decrease in appetite and weight loss. Processing of VGF generates multiple bioactive peptides, so the objective of this study was to determine the profile of the VGF-derived peptides in the brain, pituitary and plasma from Siberian hamsters, and to establish whether differential processing might occur in the short day lean state versus long day fat. Antisera against short sequences at the C- or N- termini of proVGF, as well as against NERP-1, TPGH and TLQP peptides, were used for analyses of tissues, and both immunohistochemistry and enzyme linked immunosorbent assay (ELISA coupled with high-performance liquid (HPLC or gel chromatography were carried out. VGF peptide immunoreactivity was found within cortex cholinergic perikarya, in multiple hypothalamic nuclei, including those containing vasopressin, and in pituitary gonadotrophs. ELISA revealed that exposure to short day photoperiod led to a down-regulation of VGF immunoreactivity in the cortex, and a less pronounced decrease in the hypothalamus and pituitary, while the plasma VGF levels were not affected by the photoperiod. HPLC and gel chromatography both confirmed the presence of multiple VGF-derived peptides in these tissues, while gel chromatography showed the presence of the VGF precursor in all tissues tested except for the cortex. These observations are consistent with the view that VGF-derived peptides have pleiotropic actions related to changing photoperiod, possibly by regulating cholinergic systems in the cortex, vasopressin hypothalamic pathways, and the reproductive axis.

  4. Transmission of methicillin-resistant Staphylococcus aureus between human and hamster.

    Science.gov (United States)

    Ferreira, Jorge Pinto; Fowler, Vance G; Correa, Maria T; Lyman, Roberta; Ruffin, Felicia; Anderson, Kevin L

    2011-04-01

    Transmission of methicillin-resistant Staphylococcus aureus (MRSA) between humans and animals is increasingly recognized. We newly document that the transmission of MRSA between human and hamster is possible.

  5. Non-parametric photic entrainment of Djungarian hamsters with different rhythmic phenotypes

    Czech Academy of Sciences Publication Activity Database

    Schöttner, Konrad; Hauer, J.; Weinert, D.

    2016-01-01

    Roč. 33, č. 5 (2016), s. 506-519 ISSN 0742-0528 Institutional support: RVO:60077344 Keywords : delayed activity onset * Djungarian hamster * free-running period Subject RIV: ED - Physiology Impact factor: 2.562, year: 2016

  6. Familial incidence of mammary gland tumours in the Djungarian hamster (Phodopus sungaros): a case report

    Czech Academy of Sciences Publication Activity Database

    Jelínek, F.; Felsberg, Jürgen; Měšťan, M.

    2013-01-01

    Roč. 58, č. 8 (2013), s. 442-448 ISSN 0375-8427 Institutional support: RVO:61388971 Keywords : hamsters * neoplasias * atypical fibrosarcoma Subject RIV: EE - Microbiology, Virology Impact factor: 0.756, year: 2013

  7. A Consensus Genome-scale Reconstruction of Chinese Hamster Ovary Cell Metabolism

    DEFF Research Database (Denmark)

    Hefzi, Hooman; Ang, Kok Siong; Hanscho, Michael

    2016-01-01

    Chinese hamster ovary (CHO) cells dominate biotherapeutic protein production and are widely used in mammalian cell line engineering research. To elucidate metabolic bottlenecks in protein production and to guide cell engineering and bioprocess optimization, we reconstructed the metabolic pathways...

  8. Necator americanus and Ancylostoma ceylanicum: development of protocols for dual infection in hamsters.

    Science.gov (United States)

    Rajasekariah, G R; Dhage, K R; Deb, B N; Bose, S

    1985-03-01

    Two-day-old baby hamsters were infected initially with the infective larvae of hamster-adapted human hookworm, Necator americanus (NaL3). After a specified period they were again infected orally with infective larvae of Ancylostoma ceylanicum (AcL3). Three weeks after the second infection they were killed and the establishment of N. americanus and A. ceylanicum was assessed. The effect of different infection levels and exposure period of N. americanus on the concurrent establishment of A. ceylanicum was also examined. An infection with 50 NaL3 percutaneously, and 3 weeks later, a second infection with 50 AcL3 orally has produced reasonably equal number of hookworms (no statistical difference in the burden of N. americanus and A. ceylanicum) in the intestine of hamsters. Thus this protocol of dual infection was found suitable to develop two species of hookworms in hamsters for anthelmintic screening.

  9. Allometric and radioautographic study on developing parotid gland of the golden hamster at early postnatat period

    International Nuclear Information System (INIS)

    Luca, I.M.S. de

    1989-01-01

    The post-natal development of golden hamster parotid gland and the rate of proliferation of the cells are studied in the first month of the life. A comparative evaluation with other rodents is presented. (M.A.C.) [pt

  10. Seasonal adaptation of dwarf hamsters (Genus Phodopus): differences between species and their geographic origin.

    Science.gov (United States)

    Müller, D; Hauer, J; Schöttner, K; Fritzsche, P; Weinert, D

    2015-12-01

    The genus Phodopus consists of three species--P. campbelli (Pc), P. sungorus (Ps), and P. roborovskii (Pr). They inhabit steppes, semi-deserts, and deserts in continental Asia with a climate changing from a moderate to a hard Continental one with extreme daily and seasonal variations. These different environmental challenges are likely to have consequences for hamsters' morphology, physiology, and behavior. Hamsters of all three species were investigated during the course of the year in the laboratory though using natural lighting and temperature conditions. Motor activity and body temperature were measured continuously, and body mass, testes size, and fur coloration every 1-2 weeks. With regard to the pattern of activity, nearly twice as many Pc as Ps hamsters (25 vs. 14%) failed to respond to changes of photoperiod, whereas all Pr hamsters did. Body mass and testes size were high in summer and low in winter, with the biggest relative change in Ps and the lowest in Pr hamsters. Changes of fur coloration were found in Ps hamsters only. All responding animals (that is excluding Pr), exhibited regular torpor bouts during the short winter days. In autumn, seasonal changes started considerably earlier in Ps hamsters. To investigate the putative causes of these different time courses, a further experiment was performed, to identify the critical photoperiod. Hamsters were kept for 10 weeks under different photoperiods, changing from 16 to 8 h light per day. Motor activity was recorded continuously, to identify responding and non-responding animals. Body mass was measured at the beginning and the end of the experiment, testes mass only at the end. The critical photoperiod was found to be similar in all three species. Though in a further experiment, Pc and Pr hamsters showed a delayed response, whereas the changes in Ps hamsters started immediately following transfer to short-day conditions. The results show that interspecific differences in seasonal adaptation exist, even

  11. Experimental infection of hamsters with avian paramyxovirus serotypes 1 to 9

    Directory of Open Access Journals (Sweden)

    Samuel Arthur S

    2011-02-01

    Full Text Available Abstract Avian paramyxoviruses (APMVs are frequently isolated from domestic and wild birds throughout the world and are separated into nine serotypes (APMV-1 to -9. Only in the case of APMV-1, the infection of non-avian species has been investigated. The APMVs presently are being considered as human vaccine vectors. In this study, we evaluated the replication and pathogenicity of all nine APMV serotypes in hamsters. The hamsters were inoculated intranasally with each virus and monitored for clinical disease, pathology, histopathology, virus replication, and seroconversion. On the basis of one or more of these criteria, each of the APMV serotypes was found to replicate in hamsters. The APMVs produced mild or inapparent clinical signs in hamsters except for APMV-9, which produced moderate disease. Gross lesions were observed over the pulmonary surface of hamsters infected with APMV-2 & -3, which showed petechial and ecchymotic hemorrhages, respectively. Replication of all of the APMVs except APMV-5 was confirmed in the nasal turbinates and lungs, indicating a tropism for the respiratory tract. Histologically, the infection resulted in lung lesions consistent with bronchointerstitial pneumonia of varying severity and nasal turbinates with blunting or loss of cilia of the epithelium lining the nasal septa. The majority of APMV-infected hamsters exhibited transient histological lesions that self resolved by 14 days post infection (dpi. All of the hamsters infected with the APMVs produced serotype-specific HI or neutralizing antibodies, confirming virus replication. Taken together, these results demonstrate that all nine known APMV serotypes are capable of replicating in hamsters with minimal disease and pathology.

  12. The Chemistry of Cold: Mechanisms of Torpor Regulation in the Siberian Hamster.

    Science.gov (United States)

    Cubuk, Ceyda; Bank, Jonathan H H; Herwig, Annika

    2016-01-01

    Siberian hamsters use spontaneous daily torpor, a state of hypometabolism and hypothermia, to save energy during winter. Multiple neuroendocrine signals set the scene for spontaneous torpor to occur, and several brain areas have been identified as potential sites for torpor regulation. Here, we summarize the known mechanisms of a fascinating physiological state in the Siberian hamster. ©2016 Int. Union Physiol. Sci./Am. Physiol. Soc.

  13. Evaluation of the efficacy of a recombinant subunit West Nile vaccine in Syrian golden hamsters.

    Science.gov (United States)

    Siirin, Marina T; Travassos da Rosa, Amelia P A; Newman, Patrick; Weeks-Levy, Carolyn; Coller, Beth-Ann; Xiao, Shu-Yuan; Lieberman, Michael M; Watts, Douglas M

    2008-12-01

    The efficacy of a recombinant subunit West Nile (WN) vaccine candidate was determined in a hamster model of encephalitis. Animals included young, aged, and immunocompromised animals in an effort to simulate key groups at risk of WN virus-induced disease. Groups of aged (12 month old), weanling, and adult hamsters rendered leukopenic after immunization were immunized subcutaneously with a WN virus recombinant envelope protein (WN-80E) with or without WN virus non-structural protein 1 (NS1) mixed with adjuvant or adjuvant alone. A challenge dose of wild-type WN virus was administered to produce 40-100% mortality in the control hamsters. The recombinant antigen preparations containing WN-80E with or without WN NS1 gave similar results. Hamsters in both groups had a strong antibody response after immunization, and none of the aged or weanling animals became ill or developed detectable viremia after challenge with WN virus at 2 weeks after booster vaccination. However, mortality among the control animals (administered adjuvant without antigen) at 2 weeks after booster challenge was 40-60%. In hamsters rendered leukopenic after immunization, survival rates up to 80% were observed, and a low-level viremia was detected in the vaccinated and challenged hamsters. The survival rate was significantly (Psurvival after challenge. In contrast, all of the control animals that received adjuvant only developed a very high level of viremia, and the mortality rate was 100%. These findings indicate that the recombinant WN vaccines induced antibody in and afforded protection to young and aged hamsters and immunosuppressed hamsters.

  14. MS-8209, a new amphotericin B derivative, provides enhanced efficacy in delaying hamster scrapie.

    OpenAIRE

    Adjou, K T; Demaimay, R; Lasmezas, C; Deslys, J P; Seman, M; Dormont, D

    1995-01-01

    To test the efficacy of a new amphotericin B derivative, MS-8209, in delaying scrapie, hamsters were infected intracerebrally with the 263K scrapie agent and treated with MS-8209 either early in the course of the disease or continuously. The results show that (i) all treatments lengthened the incubation period of hamster scrapie, (ii) continuous treatment with MS-8209 doubled the length of the incubation period compared with that observed in infected, untreated animals, and (iii) all treatmen...

  15. Effects of tumor-promoting phorbol diesters on neoplastic progression of Syrian hamster embryo cells.

    Science.gov (United States)

    O'Brien, T G; Saladik, D; Diamond, L

    1982-04-01

    The progression of normal Syrian hamster embryo cells to a neoplastic phenotype after treatment with a chemical carcinogen and continuous exposure to phorbol ester tumor promoters was studied in cell culture. Tumor promoters were able to rescue cell lines derived from individual carcinogen-treated colonies from a program of cellular senescence. In general, these cell lines did not grow in soft-agar medium or produce tumors in newborn hamsters at early passages but acquired these properties at later passages. These cell lines were used to study the temporal acquisition of a phenotypic characteristic of neoplastic rather than normal hamster embryo cells: the synergistic induction of the enzyme ornithine decarboxylase (ODC) by tumor promoter and serum growth factors (O'Brien, T. G., Saladik, D., and Diamond, L. Regulation of polyamine biosynthesis in normal and transformed hamster cells in culture. Biochim. Biophys. Acta, 632: 270, 1980). All cell lines that acquired neoplastic status with passage in culture exhibited the synergistic induction of ODC prior to their acquisition of the ability to either grow in soft-agar medium or produce tumors in newborn hamsters. Cell lines that responded to promoters with the synergistic induction of ODC accumulated greater levels of polyamines, especially putrescine, after promoter treatment than did normal cells. Tumor promoters did not affect the percentage of cells labeled with [3H]thymidine in preneoplastic cell lines, a finding similar to previous results in normal and neoplastic hamster cells. These studies demonstrate that tumor promoters can affect the early stages of neoplastic progression in carcinogen-treated Syrian hamster embryo cells and that a particular phenotypic property found in neoplastic hamster cells, the synergistic induction of ODC by tumor promoters and serum growth factors, is acquired by cell lines before they acquire neoplastic potential.

  16. Genomic organization and expression of immunoglobulin genes in the Chinese hamster (Cricetulus griseus).

    Science.gov (United States)

    Qin, T; Zhu, H; Wang, D; Hao, H; Du, W

    2015-01-01

    In science, the hamsters are widely used as a model for studying the human diseases because they display many features like humans. The utility of the Chinese hamster as a biology model can be further enhanced by further characterization of the genes encoding components of the immune system. Here, we report the genomic organization and expression of the Chinese hamster immunoglobulin heavy and light chain genes. The Chinese hamster IgH locus contains 268 VH segments (132 potentially functional genes, 12 ORFs and 124 pseudogenes), 4 DH segments, 6 JH segments, four constant region genes (μ, γ, ε and α) and one reverse δ remnant fragment. The Igκ locus contains only a single Cκ gene, 4 Jκ segments and 48 Vκ segments (15 potentially functional genes and 33 pseudogenes), whereas the Igλ locus contains 4 Cλ genes, but only Cλ 3 and Cλ 4 each preceded by a Jλ gene segment. A total of 49 Vλ segments (39 potentially functional genes, 3 ORFs and 7 pseudogenes) were identified. Analysis of junctions of the recombined V(D)J transcripts reveals complex diversity in both expressed H and κ sequences, but the microhomology-directed VJ recombination obviously results in very limited diversity in the Chinese hamster λ gene despite more potential germline-encoded combinatorial diversity. This is the first study to make a comprehensive analysis of the Ig genes in the Chinese hamster, which provides insights into the Ig genes in placental mammals. © 2014 John Wiley & Sons Ltd.

  17. Autoradiographic localization of tritiated dihydrotestosterone in the flank organ of the albino hamster

    International Nuclear Information System (INIS)

    Lucky, A.W.; Eisenfeld, A.J.; Visintin, I.

    1985-01-01

    In the hamster flank organ, the growth of hair and growth of sebaceous glands are androgen-dependent functions. Although dihydrotestosterone (DHT) is known to be a potent stimulator of flank organ growth, there is no information about localization of DHT receptor sites in this organ. The purpose of this study was to use steroid autoradiography to localize DHT receptors in the hamster flank organ. Because steroid hormones are functional when translocated to nuclear receptors, nuclear localization by autoradiography defines receptor sites. In order to be able to visualize autoradiographic grains from radiolabeled androgens around hair follicles, albino hamsters were studied to avoid confusion between the grains and pigment granules which are abundant in the more common Golden Syrian hamster. Mature male hamsters castrated 24 hours earlier were given tritium-labeled dihydrotestosterone ( [ 3 H]DHT). Using the technique of thaw-mount steroid autoradiography, 4-micron unfixed frozen sections were mounted in the dark onto emulsion-coated glass slides and allowed to develop for 4-6 months. [ 3 H]DHT was found to be concentrated over sebocyte nuclei. The label was present peripherally as well as in differentiating sebocytes. There was no nuclear localization of [ 3 H]DHT in animals pretreated with excessive quantities of unlabeled DHT. Steroid metabolites of [ 3 H] DHT were assessed by thin-layer chromatography in paired tissue samples. Most of the label remained with DHT. Uptake was inhibited in the flank organ of hamsters pretreated with unlabeled DHT

  18. Circadian body temperature variability is an indicator of poor prognosis in cardiomyopathic hamsters.

    Science.gov (United States)

    Ahmed, Amany; Gondi, Sreedevi; Cox, Casey; Wang, Suwei; Stupin, Igor V; Shankar, K J; Munir, Shahzeb M; Sobash, Ed; Brewer, Alan; Ferguson, James J; Elayda, Macarthur A; Casscells, S Ward; Wilson, James M

    2010-03-01

    Low body temperature is an independent predictor of poor prognosis in patients with congestive heart failure. The cardiomyopathic hamster develops progressive biventricular dysfunction, resulting in heart failure death at 9 months to 1 year of life. Our goal was to use cardiomyopathic hamsters to examine the relationship between body temperature and heart failure decompensation and death. To this end, we implanted temperature and activity transducers with telemetry into the peritoneal space of 46 male Bio-TO-2 Syrian cardiomyopathic hamsters. Multiple techniques, including computing mean temperature, frequency domain analysis, and nonlinear analysis, were used to determine the most useful method for predicting poor prognosis. Data from 44 hamsters were included in our final analysis. We detected a decline in core body temperature in 98% of the hamsters 8+/-4 days before death (P temperature variation (ie, the circadian rhythm) by using cosinor analysis, which revealed a significant decrease in the amplitude of the body temperature circadian rhythm 8 weeks before death (0.28 degrees C; 95% CI, 0.26-0.31) compared to baseline (0.36 degrees C; 95% CI, 0.34-0.39; P=.005). The decline in the circadian temperature variation preceded all other evidence of decompensation. We conclude that a decrease in the amplitude of the body temperature circadian rhythm precedes fatal decompensation in cardiomyopathic hamsters. Continuous temperature monitoring may be useful in predicting preclinical decompensation in patients with heart failure and in identifying opportunities for therapeutic intervention. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  19. Características epidemiológicas da leishmaniose tegumentar americana em uma região endêmica do Estado da Bahia: II leishmaniose canina

    OpenAIRE

    Air C. Barretto; Cesar Cuba Cuba; Júlio A. Vexenat; Ana C. Rosa; Philip D. Marsden; Albino V. Magalhães

    1984-01-01

    Um inquérito em cães realizado na região de Três Braços, Bahia, mostrou que 3,0% de 98 animais tinham amastigotas em lesões de pele. Parasitos não foram encontrados em pele normal da orelha. De uma amostra selecionada de 13 cães, portadores de lesão cutânea ativa, nove (69,2%) deles estavam comprovadamente infectados. Sete amostras de lesão produziram infecção em hamsters. O estudo biológico (crescimento em meio de cultura, evolução da lesão em hamster e desenvolvimento no tubo digestivo de L...

  20. Syrian Hamster as an Animal Model for the Study of Human Influenza Virus Infection.

    Science.gov (United States)

    Iwatsuki-Horimoto, Kiyoko; Nakajima, Noriko; Ichiko, Yurie; Sakai-Tagawa, Yuko; Noda, Takeshi; Hasegawa, Hideki; Kawaoka, Yoshihiro

    2018-02-15

    Ferrets and mice are frequently used as animal models for influenza research. However, ferrets are demanding in terms of housing space and handling, whereas mice are not naturally susceptible to infection with human influenza A or B viruses. Therefore, prior adaptation of human viruses is required for their use in mice. In addition, there are no mouse-adapted variants of the recent H3N2 viruses, because these viruses do not replicate well in mice. In this study, we investigated the susceptibility of Syrian hamsters to influenza viruses with a view to using the hamster model as an alternative to the mouse model. We found that hamsters are sensitive to influenza viruses, including the recent H3N2 viruses, without adaptation. Although the hamsters did not show weight loss or clinical signs of H3N2 virus infection, we observed pathogenic effects in the respiratory tracts of the infected animals. All of the H3N2 viruses tested replicated in the respiratory organs of the hamsters, and some of them were detected in the nasal washes of infected animals. Moreover, a 2009 pandemic (pdm09) virus and a seasonal H1N1 virus, as well as one of the two H3N2 viruses, but not a type B virus, were transmissible by the airborne route in these hamsters. Hamsters thus have the potential to be a small-animal model for the study of influenza virus infection, including studies of the pathogenicity of H3N2 viruses and other strains, as well as for use in H1N1 virus transmission studies. IMPORTANCE We found that Syrian hamsters are susceptible to human influenza viruses, including the recent H3N2 viruses, without adaptation. We also found that a pdm09 virus and a seasonal H1N1 virus, as well as one of the H3N2 viruses, but not a type B virus tested, are transmitted by the airborne route in these hamsters. Syrian hamsters thus have the potential to be used as a small-animal model for the study of human influenza viruses. Copyright © 2018 American Society for Microbiology.

  1. A lethal disease model for hantavirus pulmonary syndrome in immunosuppressed Syrian hamsters infected with Sin Nombre virus.

    Science.gov (United States)

    Brocato, Rebecca L; Hammerbeck, Christopher D; Bell, Todd M; Wells, Jay B; Queen, Laurie A; Hooper, Jay W

    2014-01-01

    Sin Nombre virus (SNV) is a rodent-borne hantavirus that causes hantavirus pulmonary syndrome (HPS) predominantly in North America. SNV infection of immunocompetent hamsters results in an asymptomatic infection; the only lethal disease model for a pathogenic hantavirus is Andes virus (ANDV) infection of Syrian hamsters. Efforts to create a lethal SNV disease model in hamsters by repeatedly passaging virus through the hamster have demonstrated increased dissemination of the virus but no signs of disease. In this study, we demonstrate that immunosuppression of hamsters through the administration of a combination of dexamethasone and cyclophosphamide, followed by infection with SNV, results in a vascular leak syndrome that accurately mimics both HPS disease in humans and ANDV infection of hamsters. Immunosuppressed hamsters infected with SNV have a mean number of days to death of 13 and display clinical signs associated with HPS, including pulmonary edema. Viral antigen was widely detectable throughout the pulmonary endothelium. Histologic analysis of lung sections showed marked inflammation and edema within the alveolar septa of SNV-infected hamsters, results which are similar to what is exhibited by hamsters infected with ANDV. Importantly, SNV-specific neutralizing polyclonal antibody administered 5 days after SNV infection conferred significant protection against disease. This experiment not only demonstrated that the disease was caused by SNV, it also demonstrated the utility of this animal model for testing candidate medical countermeasures. This is the first report of lethal disease caused by SNV in an adult small-animal model.

  2. Effect of a soybean and rice beverage on the lipid and glycemic metabolisms in hamsters Efeito da bebida de soja e arroz no metabolismo lipídico e glicêmico de hamsters

    Directory of Open Access Journals (Sweden)

    Leandra Zafalon Jaekel

    2011-12-01

    Full Text Available There is a growing interest in functional foods that, apart from their nutritional function, bring health benefits, contributing to wellbeing and/or reducing the risk of certain diseases. The objective of this study was to evaluate the functional effect of a soybean and rice beverage on the ponderal and nutritional parameters and on the lipid and glycemic metabolisms of male hamsters. Four groups of 8 animals were used: Control (commercial feed, C (commercial feed with added cholesterol, B (commercial feed plus beverage and CB (commercial feed plus cholesterol and beverage. The food efficiency coefficient was equivalent for all the groups. The weight of the liver was on average 28% heavier in groups C and CB than in the other groups, indicating cholesterol deposition in this organ. Although there was no significant difference, the concentrations of total cholesterol and of its fractions (LDL and HDL and of the triglycerides, were lower in group CB than in group C, showing a possible benefic effect of the beverage. The blood glucose concentration did not differ significantly (pÉ crescente o interesse por alimentos que, além da função de nutrir, trazem benefícios à saúde, contribuindo para o bem-estar e/ou reduzindo o risco de algumas doenças. Objetivou-se, neste estudo, avaliar o efeito funcional de bebida de soja e arroz nos parâmetros ponderais e nutricionais e no metabolismo lipídico e glicêmico de hamsters machos. Foram utilizados 4 grupos de 8 animais: Controle (ração comercial, C (ração comercial acrescida de colesterol, B (ração comercial e bebida e CB (ração comercial acrescida de colesterol e bebida. O coeficiente de eficiência alimentar foi equivalente em todos os grupos. O peso do fígado dos grupos C e CB apresentou-se em média 28% maior que os demais, indicando deposição de colesterol nesse órgão. Embora não havendo diferença significativa, as concentrações de colesterol total e suas frações (LDL e HDL

  3. Transmission of chronic wasting disease identifies a prion strain causing cachexia and heart infection in hamsters.

    Directory of Open Access Journals (Sweden)

    Richard A Bessen

    Full Text Available Chronic wasting disease (CWD is an emerging prion disease of free-ranging and captive cervids in North America. In this study we established a rodent model for CWD in Syrian golden hamsters that resemble key features of the disease in cervids including cachexia and infection of cardiac muscle. Following one to three serial passages of CWD from white-tailed deer into transgenic mice expressing the hamster prion protein gene, CWD was subsequently passaged into Syrian golden hamsters. In one passage line there were preclinical changes in locomotor activity and a loss of body mass prior to onset of subtle neurological symptoms around 340 days. The clinical symptoms included a prominent wasting disease, similar to cachexia, with a prolonged duration. Other features of CWD in hamsters that were similar to cervid CWD included the brain distribution of the disease-specific isoform of the prion protein, PrP(Sc, prion infection of the central and peripheral neuroendocrine system, and PrP(Sc deposition in cardiac muscle. There was also prominent PrP(Sc deposition in the nasal mucosa on the edge of the olfactory sensory epithelium with the lumen of the nasal airway that could have implications for CWD shedding into nasal secretions and disease transmission. Since the mechanism of wasting disease in prion diseases is unknown this hamster CWD model could provide a means to investigate the physiological basis of cachexia, which we propose is due to a prion-induced endocrinopathy. This prion disease phenotype has not been described in hamsters and we designate it as the 'wasting' or WST strain of hamster CWD.

  4. DEVELOPMENT OF MICE AND HAMSTER EMBRYOS IN KSOMAA AND HECM-6 MEDIUM

    Directory of Open Access Journals (Sweden)

    Bayu Rosadi

    2008-12-01

    Full Text Available The purpose of the present study was to investigate the viability of mice and hamster embryos developed in Kalium Simplex Optimized Medium amino acid (KSOMaa and Hamster Embryo Culture Medium-6 (HECM-6 medium. Female DDY mice were superovulated by injection i.p. of 5 IU Pregnant Mare Serum Gonadotropine (PMSG and 5 IU Human Chorionic Gonadotropine (hCG in 48 h interval, hamster (Phodopus campbelli injected by 2.5 IU PMSG and 2.5 IU hCG 48 h later. Then females were mated with fertile males. Eight-cell embryos were recovered at day 3 after natural mating. The mice embryos were cultured in KSOMaa+5% NBCS (New Born Calf Serum (T1 and HECM-6+5% NBCS (T2, the hamster embryos were cultured in KSOMaa+5% NBCS (T3 and HECM-6 + 5% NBCS (T4 for further development at 37oC in a humidified atmosphere of 5% CO2 in air for 48 h. The examinations were replicated five times. The T1 embryos developed to compact morulla and early blastocyst 100% (140/140, 92.1% (129/140 to blastocyst and expanded blastocyst, and 22.9% (32/140 became hatching/hatched. The T3 reached 100% (60/60 to compact morulla and early blastocyst, 85.0% (51/60 blastocyst, and 48.3% (29/60 expanded blastocyst, no embryo observed hatching/hatced. The T2 embryos had more expanded blastocyst than T3 (P<0.05, hatching/hatched rate higher than T1 and T3 but lower than T4 (P<0.05. Shortly, KSOMaa enable to support 8-cell stage mice and hamster embryo, but the hamster embryo developed lower at expanded blastocyst stage. HECM-6 is more appropriate than KSOMaa to support 8-cell mice embryos development and suitable to develop 8-cell stage hamster embryos.

  5. Search for rhythmicity during hibernation in the European hamster.

    Science.gov (United States)

    Canguilhem, B; Malan, A; Masson-Pévet, M; Nobelis, P; Kirsch, R; Pévet, P; Le Minor, J

    1994-01-01

    Temporal patterns of hibernation were studied by continuous monitoring of body temperature by radiotelemetry over 6 months in European hamsters, Cricetus cricetus, at constant temperature and photoperiod. Entrances into hibernation occurred mostly at the end of the night (0000-0800 hours), while arousals were randomly distributed between day and night. This is at variance with a control of bout duration by a clock with a period of 24 h. Consequently, the timing of entrances implies a phase-resetting of the circadian clock on each arousal. Persistence of circadian rhythmicity with a period different from 24 h during deep hibernation was investigated examining whether the durations of torpor bouts were integer multiples of a constant period. A non-parametric version of the classical contingency test of periodicity was developed for this purpose. Periods ranging from 21 to 29 h were tested. Nine animals out of ten showed at least one significant period in this range (P < 0.01), either below 24 h (21.8 +/- 0.5 h, n = 4) or above (27.3 +/- 0.5 h, n = 7). However, we have found a theoretical model of bout durations for which the contingency test of periodicity sometimes gives false significant results. This indicates that the power of the test is weak. With this reservation our results suggest that a circadian oscillator controls the duration of a bout of hibernation, which would occur after an integer, but variable and possibly temperature-dependent number of cycles.

  6. Obesity induction in hamster that mimics the human clinical condition.

    Science.gov (United States)

    Jordania da Silva, Vivian; Dias, Sílvia Regina Costa; Maioli, Tatiani Uceli; Serafim, Luciana Ribeiro; Furtado, Luis Fernando Viana; Quintão Silva, Maria da Gloria; Faria, Ana Maria Caetano de; Rabelo, Élida Mara Leite

    2017-08-05

    Although obesity is well established in hamsters, studies using diets with high levels of simple carbohydrate associated with lipids are necessary to assess the impact of this type of food in the body. In this study a high sugar and butter diet (HSB) and high temperature were employed towards this end. Obesity was successfully induced at a temperature of 30.3°C to 30.9°C after 38 days feeding the animals an HSB diet. It was shown that although diet is important for the induction of obesity, temperature is also essential because at a temperature slightly below the one required, obesity was not induced, even when the animals were fed for a longer period (150 days).The obese clinical condition was accompanied by biochemical and hematological changes, as increased cholesterol and triglyceride levels and increased leukocyte numbers, similar to alterations observed in obese humans. Furthermore, it was demonstrated that increasing the intake of simple carbohydrates associated with lipids provided evidence of inflammation in obese animals.

  7. Systemic immune response to Acanthamoeba keratitis in the Chinese hamster.

    Science.gov (United States)

    Van Klink, F; Leher, H; Jager, M J; Alizadeh, H; Taylor, W; Niederkorn, J Y

    1997-12-01

    Recrudescence is a common and troubling feature of Acanthamoeba keratitis and suggests that corneal infection with this organism fails to stimulate the systemic immune apparatus. The present study examined the cell-mediated and humoral immune responses to Acanthamoeba keratitis in the Chinese hamster. Corneal infection with A. castellanii failed to induce either delayed-type hypersensitivity (DTH) or serum IgG antibody against parasite antigens. The failure to induce cell-mediated and humoral immunity did not result in anergy or tolerance since subsequent intramuscular (i.m.) immunization with parasite antigens elicited robust DTH and IgG antibody responses. The inability of corneal infections to induce primary cell-mediated immune responses was due to the absence of resident antigen-presenting cells in the central cornea because induction of Langerhans cell (LC) migration into the central cornea prior to infection with Acanthamoeba promoted the development of parasite-specific DTH. Although the presence of resident LC did not promote the development of a primary humoral immune response, subsequent i.m. immunization elicited heightened parasite-specific IgG antibody production which was indicative of an anamnestic response. Collectively, the results indicate that in the absence of resident antigen-presenting cells, corneal infection with Acanthamoeba fails to stimulate primary cell-mediated or humoral immunity. Induction of peripheral LC into the central corneal epithelium promotes the development of parasite-specific DTH, but does not exacerbate corneal disease.

  8. Vitamin K metabolism in Chinese Hamster Ovary cells

    International Nuclear Information System (INIS)

    Hoffman, H.S.

    1986-01-01

    Recent investigations suggest that vitamin K may have functions other than in blood coagulation and calcification. The present study was undertaken to investigate this hypothesis using cells in culture. Chinese Hamster Ovary (CHO) cells were chosen due to their active metabolism and growth and lack of similarity to liver and bone cells, in which vitamin K metabolism is well known. Cells were adapted to serum-free media, incubated in media containing the appropriate concentrations of vitamin K for specified times, scraped from plates, pelleted, extensively washed to remove adhering vitamin K, extracted with chloroform:methanol (2:1, v/v) and analyzed on C18 HPLC columns. Uptake of vitamin K by CHO cells follows saturation kinetics at vitamin K concentrations up to 25 μ M and is transported into cells at the rate of 10 pmol/min. 10 6 cells. After 24 hours, 3 H vitamin K is metabolized by CHO cells to several compounds, the major of which was isolated and identified as vitamin K epoxide. In 3 experiments, after 24 hours, the average cellular uptake of vitamin K was 8% with approximately half being metabolized to vitamin K epoxide. These results demonstrate that vitamin K is metabolized in cells with widely different functions and suggest a generalized function for vitamin K which has yet to be elucidated

  9. Investigation of estrogen receptor functionality in hamster melanoma

    International Nuclear Information System (INIS)

    Hitselberger, M.H.

    1987-01-01

    The biology of hamster melanoma, HM1, was assessed congenitally athymic mice after administration of estradiol. Chronic treatment with this steroid hormone delayed tumor appearance in females, inhibited tumor growth in both sexes and reduced the number of lung metastatic lesions in males. Cytosol and nuclear estrogen receptors were characterized in HM1 cells. Specific binding in both fractions was saturable and indicative of high affinity sites with a mean Kd of 0.22 nM in the cytosol and 1.5 nM in the nucleus. Sucrose density-gradient centrifugation of 3 H-estradiol-labelled cytosol demonstrated a peak in the 8S-9S region, which was completely suppressible by excess diethylstilbesterol. To determine whether the estrogen receptor in HM1 cells was functional, athymic mice received 2.5 μg estradiol or vehicle s.c. and were necroscopied 1, 2, 6 and 24 hr later. Nuclear estrogen receptor content was maximal one hr after injection of estradiol and declined to control levels by 24 hr. This effect was accompanied by a rapid reduction in cytosol estrogen receptor content which returned to control levels by 24 hr. A physiologic dose of estradiol, 0.1 μg, injected one hr prior to necroscopy, produced maximal changes in cytosol and nuclear estrogen receptor content

  10. Neocarzinostatin-mediated DNA damage and repair in wild-type and repair-deficient Chinese hamster ovary cells

    International Nuclear Information System (INIS)

    Kuo, W.L.; Meyn, R.E.; Haidle, C.W.

    1984-01-01

    The formation and repair of neocarzinostatin (NCS)-mediated DNA damage were examined in two strains of Chinese hamster ovary cells. The response in strain EM9, a mutant line selected for its sensitivity to ethyl methanesulfonate and shown to have a defect in the repair of X-ray-induced DNA breaks, was compared with that observed in the parental strain (AA8). The DNA strand breaks and their subsequent rejoining were measured using the method of elution of DNA from filters under either alkaline (for single-strand breaks), or nondenaturing conditions (for double-strand breaks). Colony survival assays showed that the mutant was more sensitive to the action of NCS than was the parental strain by a factor of approximately 1.5. Elution analyses showed that the DNA from both strains was damaged by NCS; the mutant displayed more damage than the parent under the same treatment conditions. Single-strand breaks were produced with a frequency of about 10 to 15 times the frequency of double-strand breaks. Both strains were able to rejoin both single-strand breaks and double-strand breaks induced by NCS treatment. The strand break data suggest that the difference in NCS-mediated cytotoxicity between EM9 and AA8 cells may be directly related to the enhanced production of DNA strand breaks in EM9. However, the fact that much higher doses of NCS were required in the DNA studies compared to the colony survival assays implies that either a small number of DNA breaks occur in a critical region of the genome, or that lesions other than DNA strand breaks are partly responsible for the observed cytotoxicity

  11. Detection of Leptospira spp. in the semen and urine of bulls serologically reactive to Leptospira interrogans serovar hardjo Detecção de Leptospira spp. em sêmen e urina de touros sorologicamente reagentes a Leptospira interrogans sorovar hardjo

    Directory of Open Access Journals (Sweden)

    Fernanda Senter Magajevski

    2005-03-01

    Full Text Available This study evaluated PCR for the detection of leptospires in semen and urine of ten serologically reactive bulls, comparing these results with those obtained with other diagnosis techniques. Two collections of materials were done in alternate days. Semen and urine samples were separated in aliquots for: direct visualization in dark field microscopy; inoculation in hamsters (for semen only; isolation in culture media; and PCR. No hamster was positive by the microscopic agglutination test (MAT; kidney and liver fragments from the hamsters were used in an isolation attempt in culture media, with one positive isolation from the kidney of a hamster inoculated with semen of one bull, and from liver of hamsters inoculated with semen of three bulls. Isolation in culture was negative for all semen samples, but positive for five urine samples by direct inoculation. In PCR there was no positive result for semen samples, and only one urine sample was positive, which was coincident with one of the positive cultures. It was not possible to visualize leptospires in any of the samples by dark field microscopy.O presente trabalho avaliou a PCR na detecção de leptospiras em sêmen e urina de dez touros sorologicamente reagentes, comparando seus resultados com aqueles obtidos por outras técnicas de diagnóstico. Foram realizadas duas colheitas de materiais em dias alternados. As amostras de sêmen e de urina foram separadas em alíquotas para visualização direta em microscopia de campo escuro, inoculação em hamsters (apenas para o sêmen, isolamento em meio de cultura e PCR. Nenhum hamster apresentou positividade na prova de soroaglutinação microscópica (SAM; fragmentos de rins e fígado desses animais foram utilizados para a tentativa de isolamento em meio de cultura, sendo positivo o cultivo a partir do rim de hamster inoculado com semen de um touro, e do fígado de hamsters inoculados com o semen de três touros. O isolamento em meio de cultura foi

  12. The effect of dietary vitamin A on NO2 exposure on the hamster lung

    International Nuclear Information System (INIS)

    Kim, J.C.

    1978-01-01

    The effect of dietary vitamin A and NO2 exposure on the hamster lung was evaluated by histopathology, electron microscopy, and thymidine uptake studies. Hamsters were maintained on deficient (0 micrograms), adequate (100 micrograms), and high (200 micrograms) dose levels of vitamin A while being exposed repeatedly to 10 ppm of NO2 for 5 hours once a week over an 8-week period. Hamsters of the deficient group exhibited clinical and morphologic changes characteristic of vitamin A deficiency. Animals maintained on adequate and high dose levels of vitamin A were not affected by vitamin A deficiency. Hypertrophy and hyperplasia of the epithelial cells of the terminal bronchiolar alveolar region of lungs of adequately and highly dosed animals were greater than those observed in the deficient animals, when NO2 exposure was given. However, the extent of the lesions observed in all three groups was less than that seen in normal hamsters given a single, 5-hour NO2 exposure. Ultrastructural changes observed in vitamin A-deficient hamsters exposed to NO2 were hypertrophy and hyperplasia of bronchiolar epithelial cells, diffuse loss of cilia, membrane damage, and mitochondrial damage manifested by calcium deposition. Tritiated thymidine uptake studies of lungs of animals exposed repeatedly revealed a rather erratic cell renewal pattern following NO2 exposure in comparison to the group of animals exposed singly

  13. Central vasopressin infusion prevents hibernation in the European hamster (Cricetus cricetus).

    Science.gov (United States)

    Hermes, M L; Buijs, R M; Masson-Pévet, M; van der Woude, T P; Pévet, P; Brenklé, R; Kirsch, R

    1989-01-01

    The amount of immunocytochemically detectable vasopressin in the brain of the European hamster (Cricetus cricetus) shows a seasonal variation; i.e., dense vasopressin immunoreactivity is present in the lateral septum during summer but is absent in autumn and winter [Buijs, R. M., Pévet, P., Masson-Pévet, M., Pool, C. W., De Vries, G. J., Canguilhem, B. & Vivien-Roels, B. (1986) Brain Res. 371, 193-196]. In the winter period the European hamster hibernates. Since vasopressin in the lateral septum is known to be involved in the control of body temperature, we investigated whether infusion of vasopressin in the lateral septum during autumn-winter could influence hypothermic patterns normally seen in hibernating animals. Hamsters whose lateral septum was infused with vasopressin showed almost no periods of hypothermia, whereas hamsters treated with control infusions displayed a normal hibernation pattern. The results indicate that persistence of vasopressin release in the lateral septum of the European hamster during winter can prevent hibernation. Images PMID:2762331

  14. Effects of light deprivation on prolactin regulation in the Golden Syrian hamster

    International Nuclear Information System (INIS)

    Massa, J.S.

    1986-01-01

    Pineal-mediated depressions in prolactin cell activity after light deprivation were studied in the male and female Golden Syrian hamster. Prolactin cell activity was determined by measuring radioimmunoassayable prolactin, newly synthesized prolactin, newly synthesized prolactin and prolactin mRNA levels in the pituitary. Serum prolactin was also measured by radioimmunoassay. Use of the recombinant DNA plasmid, pPRL-1, which contains the rat prolactin complimentary DNA sequence, was validated in this dissertation for measuring prolactin mRNA in the hamster. Male Hamsters blinded for 11, 21, or 42 days showed significant and progressively greater declines in prolactin mRNA levels which were completely prevented by pinealectomy. Female hamsters blinded for 28 days, however, showed no such decreases in prolactin cell activity if they continued to display estrous cyclicity. After 12 weeks of blinding, females were acyclic and had dramatically depressed levels of prolactin cell activity. However, pinealectomy did not completely prevent this decline due to blinding unless the females continue to display estrous cyclicity. In ovariectomized females, blinding caused a decline in prolactin cell activity. In a separate study, significant changes in prolactin cell activity during the estrous cycle were seen in untreated normally cycling female hamsters. These changes in prolactin mRNA, prolactin synthesis, and radioimmunoassayable prolactin in the pituitary were measured in the morning, when, consistent with other reports, no differences in serum prolactin were observed

  15. Stimulatory effect of RFRP-3 on the gonadotrophic axis in the male Syrian hamster

    DEFF Research Database (Denmark)

    Ancel, Caroline; Bentsen, Agnete H; Sébert, Marie-Emilie

    2012-01-01

    In seasonal mammals, a distinct photoneuroendocrine circuit that involves the pineal hormone melatonin tightly synchronizes reproduction with seasons. In the Syrian hamster, a seasonal model in which sexual activity is inhibited by short days, we have previously shown that the potent GnRH stimula......In seasonal mammals, a distinct photoneuroendocrine circuit that involves the pineal hormone melatonin tightly synchronizes reproduction with seasons. In the Syrian hamster, a seasonal model in which sexual activity is inhibited by short days, we have previously shown that the potent Gn...... in the Syrian hamster, is strongly down-regulated by melatonin in short days. Because a large body of evidence now indicates that RFamide-related peptide (RFRP)-3, the product of the rfrp gene, is an inhibitor of gonadotropin secretion in various mammalian species, we sought to investigate its effect...... on the gonadotrophic axis in the Syrian hamster. We show that acute central injection of RFRP-3 induces c-Fos expression in GnRH neurons and increases LH, FSH, and testosterone secretion. Moreover, chronic central administration of RFRP-3 restores testicular activity and Kiss1 levels in the arcuate nucleus of hamsters...

  16. Propagation of Asian isolates of canine distemper virus (CDV in hamster cell lines

    Directory of Open Access Journals (Sweden)

    Yamaguchi Ryoji

    2009-10-01

    Full Text Available Abstract Backgrounds The aim of this study was to confirm the propagation of various canine distemper viruses (CDV in hamster cell lines of HmLu and BHK, since only a little is known about the possibility of propagation of CDV in rodent cells irrespective of their epidemiological importance. Methods The growth of CDV in hamster cell lines was monitored by titration using Vero.dogSLAMtag (Vero-DST cells that had been proven to be susceptible to almost all field isolates of CDV, with the preparations of cell-free and cell-associated virus from the cultures infected with recent Asian isolates of CDV (13 strains and by observing the development of cytopathic effect (CPE in infected cultures of hamster cell lines. Results Eleven of 13 strains grew in HmLu cells, and 12 of 13 strains grew in BHK cells with apparent CPE of cell fusion in the late stage of infection. Two strains and a strain of Asia 1 group could not grow in HmLu cells and BHK cells, respectively. Conclusion The present study demonstrates at the first time that hamster cell lines can propagate the majority of Asian field isolates of CDV. The usage of two hamster cell lines suggested to be useful to characterize the field isolates biologically.

  17. Response of adult Necator americanus to some known anthelminthics in hamsters.

    Science.gov (United States)

    Rajasekariah, G R; Deb, B N; Dhage, K R; Bose, S

    1989-06-01

    Adult Necator americanus infection in laboratory hamsters (the hamster-hookworm model) was examined as an anthelminthic screening system. Three reference anthelminthics--pyrantel (PYTL), mebendazole (MBZ) and ivermectin (IVRN)--were used to assess the sensitivity of adult N. americanus and also to investigate the value of the hamster-hookworm model for predicting clinical results. Serial drug dosages were used, and the ED50 was determined from the resulting cure rates. In addition, percentage worm reductions were calculated by reference to the worm burdens in control groups. The results showed that the hamster-hookworm model was able to differentiate anthelminthics on their efficacy. Absolute activity (100% worm reduction) followed treatment with 8 mg kg-1 MBZ, 38-40 mg kg-1 PYTL and 18 mg kg-1 IVRN. Based on ED50 data of PYTL and MBZ, adult N. americanus appeared to be two to five times more sensitive than pre-adult stages. However, with IVRN the reverse appeared true. MBZ appeared to be most active and PYTL least active in terms of curing infected animals, but there were no obvious differences between the rates of worm reductions following single or multiple doses of anthelminthics. It is considered that the hamster-hookworm model will prove of value in identifying and characterizing possible new anthelminthics.

  18. Expression patterns of Doppel gene in golden hamster: quantification using real-time RT-PCR.

    Science.gov (United States)

    Li, Y R; Li, Q; Yang, J M; Zhou, X M; Yin, X M; Zhao, D M

    2008-08-01

    Doppel (prion-like protein, Dpl) may act as a useful molecular marker in tumor diagnosis and in tumor grade definition, as over-expression of Dpl protein has been found in tumors with different histologic origin. Accordingly, the quantitative analysis of the expression of Dpl in different tissues is essential for understanding its role in tumor progression and cancer diagnostic. Herein we report Dpl mRNA quantification in golden hamster by calibrated highly sensitive externally standardized real-time RT-PCR with LightCycler instrument. Total RNA was isolated from nine different organs of golden hamster in different stages of development: from neonatal to adult golden hamster. Highest level of Dpl mRNA was detected in the testis, and lower levels of Dpl mRNA were detected in the following tissues: spleen, heart, bone marrow, skeletal muscles and neocortex (only in neonatal hamster). The expression of Dpl was not detected in kidney, liver and lung. This is the first study to report the expression of Dpl in bone marrow of murine and the difference of expression levels of Dpl in testis between adult and neonatal hamsters.

  19. Temperature regulation in the mouse and hamster exposed to microwaves in hot environments

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, C.J.; Long, M.D.; Fehlner, K.S.; Stead, A.G.

    1986-01-01

    Colonic temperature was measured in naive BALB/c mice and golden hamsters immediately following 90-min exposures to 2450-MHz radiofrequency (RF) radiation at an ambient temperature (Ta) of 32.2 or 35 C (dry air). Exposures were performed in a temperature-controlled waveguide that permitted continuous monitoring of the specific absorption rate (SAR) of RF energy. At a Ta of 32.2 C, the threshold SAR for elevating colonic temperature and the SAR resulting in a 1.0 C elevation in colonic temperature were, respectively, 4.3 and 10.0 W/kg for the mouse and 0.69 and 1.9 W/kg for the hamster. At a Ta of 35 C, these values were 0.12 and 5.3 W/kg for the mouse and 0.46 and 1.4 W/kg for the hamster. The SARs required to induce hyperthermia in the mouse and hamster at these relatively warm Ta's are considerably lower than those required at cooler Ta's of 20 to 3 C. Overall, the hamster became hyperthermic at lower SARs than in the mouse. Ta's of 35 C and greater are frequently encountered during heat waves in the summer months.

  20. Thermogenin amount and activity in hamster brown fat mitochondria: effect of cold acclimation

    International Nuclear Information System (INIS)

    Sundin, U.; Moore, G.; Nedergaard, J.; Cannon, B.

    1987-01-01

    To investigate the acclimation process in a hibernator, four different parameters of thermogenin amount and activity were investigated in brown adipose tissue mitochondria from cold-exposed and cold-acclimated Syrian hamsters. Hamsters, which are hibernators, have been considered to be primed for thermogenesis and thus not to show cold-acclimation effects, but here a significant increase in [ 3 H]GDP-binding capacity was observed, and this increase was paralleled by an increase in thermogenin antigen amount, as measured in an enzyme-linked immunosorbent assay. The transient nature of the effect of cold exposure on [ 3 H]GDP binding, characteristically observed with rat mitochondria, was not observed with hamster mitochondria, and the increase in [ 3 H]GDP binding occurred without a change in the dissociation constant. The increase in thermogenin amount was paralleled by an increase both in GDP-sensitive Cl - permeability of the mitochondria and in GDP-sensitive respiration. It was established that it is the maximal activity of thermogenin that is rate limiting for thermogenesis in isolated mitochondria, provided that an optimal substrate is used (such as palmitoyl carnitine). Cold acclimation also increased the total amount of mitochondria in the tissue, leading totally to a sixfold increase in thermogenin content of the hamster. It is concluded that hamsters show the expected physiological, pharmacological, and biochemical signs of cold acclimation

  1. Body temperature circadian rhythm variability corresponds to left ventricular systolic dysfunction in decompensated cardiomyopathic hamsters.

    Science.gov (United States)

    Ahmed, Amany; Gondi, Sreedevi; Cox, Casey; Zheng, Minjuan; Mohammed, Anwarullah; Stupin, Igor V; Wang, Suwei; Vela, Deborah; Brewer, Alan; Elayda, Macarthur A; Buja, L Maximilian; Ward Casscells, S; Wilson, James M

    2011-11-01

    A declining amplitude of body temperature circadian rhythm (BTCR) predicts decompensation or death in cardiomyopathic hamsters. We tested the hypothesis that changes in BTCR amplitude accompany significant changes in left ventricular (LV) size and function. Using intraperitoneal transmitters, we continuously monitored the temperature of 30 male BIO TO-2 Syrian dilated cardiomyopathic hamsters. Cosinor analysis was used to detect significant changes--defined as changes >1 standard deviation from the baseline amplitude for 3 consecutive days--in BTCR amplitude over each hamster's lifespan. The Student t-test was used to compare BTCR variability and LV size and function (as assessed by 2D echocardiography) between baseline and the time that BTCR amplitude declined. All hamsters received 10 mg/kg furosemide daily. At the time of BTCR amplitude decline, functional parameters had changed significantly (P < .0001) from baseline: ejection fraction (0.31 ± 0.09% vs. 0.52 ± 0.08%), LV end-systolic volume (0.11 ± 0.03 vs. 0.05 ± 0.02 cm(3)), and LV end-diastolic volume (0.16 ± 0.04 vs. 0.10 ± 0.03 cm(3)). In decompensated cardiomyopathic hamsters, a decline in BTCR amplitude was associated with progression of heart failure and cardiac decompensation. Variation in BTCR warrants further investigation because of its potential implications for the diagnosis and treatment of cardiovascular disorders. Published by Elsevier Inc.

  2. Effects of aqueous cinnamon extract on chemically-induced carcinoma of hamster cheek pouch mucosa

    Directory of Open Access Journals (Sweden)

    Samah K. Ezzat

    2017-12-01

    Full Text Available This study aimed to investigate the effects of aqueous cinnamon extract (ACE on 7, 12-Dimethylbenz[a]anthracene (DMBA-induced oral carcinogenesis in hamster cheek pouch (HCP mucosa. Sixty male Syrian hamsters were randomly divided into six equal groups. The hamsters of groups I, II and III received no treatment, DMBA and ACE respectively, for 16 weeks. Groups IV and V were handled as group II and concomitantly treated with ACE for the same period and additionally group V received ACE for other 16 weeks after the stoppage of DMBA application. Group VI hamsters were handled as group III and additionally received DMBA for other 16 weeks after the stoppage of ACE supplementation. Hamsters of each group were euthanized according to the experimental schedule. The buccal pouches were and prepared for H&E stain, PAS reagent, CD3 and PDGF immunohistochemical reactivity. All groups showed dysplastic changes with varying degrees except groups I and III. Deep invasive carcinomas were recorded in 90% of the samples of group II, 60% of group IV, 50% of group V and 40% of group VI. From the previous results, it can be concluded that ACE has the potentiality preventing oral cancer initiation better than inhibiting oral cancer progression.

  3. Butter blend containing fish oil improves the level of n-3 fatty acids in biological tissues of hamster

    DEFF Research Database (Denmark)

    Porsgaard, Trine; Overgaard, Jesper; Krogh, Anne Louise

    2007-01-01

    Syrian hamsters received hamster feed blended with one of the three butter products. After 6 weeks of feeding, the fatty acid compositions of plasma, erythrocytes, liver, brain, and visceral fat were determined. The intake of butter product with fish oil resulted in a higher level of n-3 PUFA in plasma...

  4. Genomic landscapes of Chinese hamster ovary cell lines as revealed by the Cricetulus griseus draft genome

    DEFF Research Database (Denmark)

    Lewis, Nathan E; Liu, Xin; Li, Yuxiang

    2013-01-01

    Chinese hamster ovary (CHO) cells, first isolated in 1957, are the preferred production host for many therapeutic proteins. Although genetic heterogeneity among CHO cell lines has been well documented, a systematic, nucleotide-resolution characterization of their genotypic differences has been...... stymied by the lack of a unifying genomic resource for CHO cells. Here we report a 2.4-Gb draft genome sequence of a female Chinese hamster, Cricetulus griseus, harboring 24,044 genes. We also resequenced and analyzed the genomes of six CHO cell lines from the CHO-K1, DG44 and CHO-S lineages....... This analysis identified hamster genes missing in different CHO cell lines, and detected >3.7 million single-nucleotide polymorphisms (SNPs), 551,240 indels and 7,063 copy number variations. Many mutations are located in genes with functions relevant to bioprocessing, such as apoptosis. The details...

  5. Peripheral kisspeptin reverses short photoperiod-induced gonadal regression in Syrian hamsters by promoting GNRH release

    DEFF Research Database (Denmark)

    Ansel, L; Bentsen, A H; Ancel, C

    2011-01-01

    In seasonal breeders, reproduction is synchronised by day length via the pineal hormone melatonin. In short winter days (short day, SD), the Syrian hamster displays a complete gonadal atrophy together with a marked reduction in expression of kisspeptins (Kp), a family of potent hypothalamic...... stimulators of GNRH neurons. Both central and peripheral acute injections of Kp have been reported to activate the gonadotropic axis in mammals. The aim of this study was to determine if and how peripheral administration of Kp54 could restore gonadal function in photo-inhibited hamsters. Testicular activity...... of hamsters kept in SD was reactivated by two daily i.p. injections of Kp54 but not by chronic subcutaneous delivery of the same peptide via mini-pumps. Acute i.p. injection of Kp54-induced FOS (c-Fos) expression in a large number of GNRH neurons and pituitary gonadotrophs together with a strong increase...

  6. Blood Vessel Normalization in the Hamster Oral Cancer Model for Experimental Cancer Therapy Studies

    Energy Technology Data Exchange (ETDEWEB)

    Ana J. Molinari; Romina F. Aromando; Maria E. Itoiz; Marcela A. Garabalino; Andrea Monti Hughes; Elisa M. Heber; Emiliano C. C. Pozzi; David W. Nigg; Veronica A. Trivillin; Amanda E. Schwint

    2012-07-01

    Normalization of tumor blood vessels improves drug and oxygen delivery to cancer cells. The aim of this study was to develop a technique to normalize blood vessels in the hamster cheek pouch model of oral cancer. Materials and Methods: Tumor-bearing hamsters were treated with thalidomide and were compared with controls. Results: Twenty eight hours after treatment with thalidomide, the blood vessels of premalignant tissue observable in vivo became narrower and less tortuous than those of controls; Evans Blue Dye extravasation in tumor was significantly reduced (indicating a reduction in aberrant tumor vascular hyperpermeability that compromises blood flow), and tumor blood vessel morphology in histological sections, labeled for Factor VIII, revealed a significant reduction in compressive forces. These findings indicated blood vessel normalization with a window of 48 h. Conclusion: The technique developed herein has rendered the hamster oral cancer model amenable to research, with the potential benefit of vascular normalization in head and neck cancer therapy.

  7. Healing acceleration in hamsters of oral mucositis induced by 5-fluorouracil with topical Calendula officinalis.

    Science.gov (United States)

    Tanideh, Nader; Tavakoli, Parisa; Saghiri, Mohammad Ali; Garcia-Godoy, Franklin; Amanat, Dariush; Tadbir, Azadeh Andisheh; Samani, Soleiman Mohammadi; Tamadon, Amin

    2013-03-01

    This study assessed the potential of topical Calendula officinalis extract on the healing of oral mucositis induced by 5-fluorouracil (5-FU) in hamsters. Oral mucositis was induced in 60 male hamsters by 5-FU (60 mg/kg) on days 0, 5, and 10 of the study. The cheek pouch was scratched with a sterile needle on days 1 and 2. On days 12-17, 5% and 10% C. officinalis gel and gel base groups were treated and then compared with a control group. Macroscopic and microscopic scores and weights were evaluated. Microscopic and macroscopic scores of mucositis were lower in the 5% and 10% C. officinalis gel groups than in the gel base and control groups (P Calendula officinalis extract accelerated the healing of oral mucositis in hamsters. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Efficacy of minocycline and tigecycline in a hamster model of leptospirosis.

    Science.gov (United States)

    Tully, Charla C; Hinkle, Mary K; McCall, Suzanne; Griffith, Matthew E; Murray, Clinton K; Hospenthal, Duane R

    2011-12-01

    Leptospirosis is a widespread zoonotic infection characterized by acute febrile illness. Severely ill patients may require empiric treatment with broad-spectrum antibiotics prior to definitive diagnosis. We evaluated the efficacy of minocycline and tigecycline against leptospirosis in a hamster model. Hamsters were treated with either minocycline (5, 10, or 25 mg/kg per day) or tigecycline (5, 10, or 25 mg/kg per day) for 5 days. Controls included untreated animals and doxycycline-treated animals (5 mg/kg per day). Nine days after infection, all untreated animals were dead. All treated hamsters survived to the end of study (day 21). Study groups showed significantly improved survival compared to the untreated group (P < .01). Minocycline and tigecycline showed survival benefit comparable to the standard treatment, doxycycline. In the absence of doxycycline, minocycline may be considered as an alternative, while tigecycline may be useful in the management of severely ill patients prior to a definitive diagnosis. Published by Elsevier Inc.

  9. Blood leukocyte and spleen lymphocyte immune response of spleen lymphocytes and whole blood leukocytes of hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Peters, B.A.; Sothmann, M.; Wehrenberg, W.B. (Univ. of Wisconsin, Milwaukee (USA))

    1989-01-01

    This study was designed to evaluate the effects of chronic physical activity on the immune response of spleen lymphocytes and whole blood leukocytes of hamsters. Animals were kept sedentary or allowed to exercise spontaneously on running wheels for eight weeks. Physically active animals averaged 12 kilometers per day. The immune response of spleen lymphocytes whole blood leukocytes was evaluated by {sup 3}H-thymidine incorporation in response to Concanavalin A or lipopolysaccharide. There was no treatment effect between physically active and sedentary hamster in response of spleen lymphocytes. The immune response of whole blood leukocytes to these mitogens was significantly greater in physically active vs. sedentary hamsters. These results demonstrate that chronic physical activity has the capacity to modulate immunoresponses.

  10. Zika virus infection of adult and fetal STAT2 knock-out hamsters.

    Science.gov (United States)

    Siddharthan, Venkatraman; Van Wettere, Arnaud J; Li, Rong; Miao, Jinxin; Wang, Zhongde; Morrey, John D; Julander, Justin G

    2017-07-01

    Zika virus (ZIKV) infection was investigated in adult and fetal STAT2 knock-out (KO) hamsters. Subcutaneous injection of ZIKV of adults resulted in morbidity, mortality, and infection of the uterus, placenta, brain, spinal cord, and testicles, thus providing an opportunity to evaluate congenital ZIKV infection in a second rodent species besides mice. ZIKV-infected cells with morphologies of Sertoli cells and spermatogonia were observed in the testes, which may have implications for sexual transmission and male sterility. Neonates exposed as fetuses to ZIKV at 8 days post-coitus were not smaller than controls. Nevertheless, infectious virus and ZIKV RNA was detected in some, but not all, placentas and fetal brains of KO hamsters. STAT2 KO hamsters may be useful for addressing sexual transmission, pathogenesis, routes of fetal infection, and neurological disease outcomes, and may also be used in antiviral or vaccine studies to identify intervention strategies. Copyright © 2017. Published by Elsevier Inc.

  11. DIP and DIP + 2 as glutathione oxidants and radiation sensitizers in cultured Chinese hamster cells

    International Nuclear Information System (INIS)

    Harris, J.W.; Power, J.A.; Kosower, N.S.; Kosower, E.M.

    1975-01-01

    Two diamide analogues, diazene dicarboxylic acid bis (N'-methyl-piperazide) or DIP, and its bis-N'-methyl iodide salt, or DIP + 2, were tested for their ability to penetrate cultured Chinese hamster cells and oxidize intracellular glutathione. DIP penetrated the cells at a reasonable rate at 18 0 C, 160 nmoles being required to oxidize the endogenous glutathione of 2 x 10 6 cells, but it penetrated very slowly at 0 0 C. DIP + 2 did not effectively oxidize glutathione in Chinese hamster cells, possibly because it did not enter the cels. DIP became toxic after about 10 min of exposure, but its toxicity could be moderated by using anoxic conditions. DIP, but not DIP + 2, sensitized anoxic Chinese hamster cells to X-radiation by a factor of 1.5, an effect that was due entirely to removal of the shoulder from the survival curve. (author)

  12. Multistep change in epidermal growth factor receptors during spontaneous neoplastic progression in Chinese hamster embryo fibroblasts

    International Nuclear Information System (INIS)

    Wakshull, E.; Kraemer, P.M.; Wharton, W.

    1985-01-01

    Whole Chinese hamster embryo lineages have been shown to undergo multistep spontaneous neoplastic progression during serial passage in culture. The authors have studied the binding, internalization, and degradation of 125 I-labeled epidermal growth factor at four different stages of transformation. The whole Chinese hamster embryo cells lost cell surface epidermal growth factor receptors gradually during the course of neoplastic progression until only 10% of the receptor number present in the early-passage cells (precrisis) were retained in the late-passage cells (tumorigenic). No differences in internalization rates, chloroquine sensitivity, or ability to degrade hormone between the various passage levels were seen. No evidence for the presence in conditioned medium of transforming growth factors which might mask or down-regulate epidermal growth factor receptor was obtained. These results suggest that a reduction in cell surface epidermal growth factor receptor might be an early event during spontaneous transformation in whole Chinese hamster embryo cells

  13. Alterations of male sexual behavior by learned aversions to hamster vaginal secretion.

    Science.gov (United States)

    Johnston, R E; Zahorik, D M; Immler, K; Zakon, H

    1978-02-01

    Male hamsters poisoned after their first adult exposure to the vaginal secretion of female hamsters became hesitant to approach and ingest the secretion. The same aversion-training procedure also altered the responses of males to estrous females, changing the latency, frequency, and duration of a variety of behaviors that are commonly taken as indexes of sexual attraction or arousal and of copulatory performance. The effects suggest that the aversions to vaginal secretion alter the perceived meaning of the secretion for male hamsters, and analysis of the correlations between various measures of sexual arousal and performance support the hypothesis that separate mechanisms underlie the effects of the secretion on appetitive and consummatory sexual behavior.

  14. Stressors, including social conflict, decrease plasma prolactin in male golden hamsters.

    Science.gov (United States)

    Huhman, K L; Mougey, E H; Moore, T O; Meyerhoff, J L

    1995-12-01

    Following exposure to a stressor, plasma prolactin (PRL) rises in most species. The purpose of the present study was to examine the effect of social conflict or of footshock stress on PRL responsiveness in male Syrian hamsters. Contrary to expectations, PRL was significantly lower in subordinate hamsters than in their dominant opponents or in controls following one, five, or nine exposures to social conflict. Similarly, PRL was reduced in hamsters subjected to a mild footshock stressor. By contrast, adrenocorticotropin, another stress-responsive hormone, was elevated following exposure to each of these stressors. We also demonstrate that PRL release is inhibited by dopamine as it is in other species by showing that there is a dose-dependent increase in PRL release following treatment with the dopamine receptor blocker, domperidone.

  15. Adapting to alcohol: Dwarf hamster (Phodopus campbelli) ethanol consumption, sensitivity, and hoard fermentation.

    Science.gov (United States)

    Lupfer, Gwen; Murphy, Eric S; Merculieff, Zoe; Radcliffe, Kori; Duddleston, Khrystyne N

    2015-06-01

    Ethanol consumption and sensitivity in many species are influenced by the frequency with which ethanol is encountered in their niches. In Experiment 1, dwarf hamsters (Phodopus campbelli) with ad libitum access to food and water consumed high amounts of unsweetened alcohol solutions. Their consumption of 15%, but not 30%, ethanol was reduced when they were fed a high-fat diet; a high carbohydrate diet did not affect ethanol consumption. In Experiment 2, intraperitoneal injections of ethanol caused significant dose-related motor impairment. Much larger doses administered orally, however, had no effect. In Experiment 3, ryegrass seeds, a common food source for wild dwarf hamsters, supported ethanol fermentation. Results of these experiments suggest that dwarf hamsters may have adapted to consume foods in which ethanol production naturally occurs. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Selective inhibition of CYP27A1 and of chenodeoxycholic acid synthesis in cholestatic hamster liver.

    Science.gov (United States)

    Matsuzaki, Yasushi; Bouscarel, Bernard; Ikegami, Tadashi; Honda, Akira; Doy, Mikio; Ceryak, Susan; Fukushima, Sugano; Yoshida, Shigemasa; Shoda, Junichi; Tanaka, Naomi

    2002-11-20

    The aim of this study was to explore the regulation of serum cholic acid (CA)/chenodeoxycholic acid (CDCA) ratio in cholestatic hamster induced by ligation of the common bile duct for 48 h. The serum concentration of total bile acids and CA/CDCA ratio were significantly elevated, and the serum proportion of unconjugated bile acids to total bile acids was reduced in the cholestatic hamster similar to that in patients with obstructive jaundice. The hepatic CA/CDCA ratio increased from 3.6 to 11.0 (PCYP27A1 is, at least in part, responsible for the relative decreased production of CDCA and increased CA/CDCA ratio in the liver, bile and serum of cholestatic hamsters.

  17. Differential regulation of kiss1 expression by melatonin and gonadal hormones in male and female Syrian hamsters

    DEFF Research Database (Denmark)

    Ansel, L; Bolborea, M; Bentsen, A H

    2010-01-01

    In seasonal breeders, reproduction is synchronized to seasons by day length via the pineal hormone melatonin. Recently, we have demonstrated that Kiss1, a key activator of the reproductive function, is down-regulated in sexually inactive hamsters maintained in inhibitory short days (SDs...... differentially regulate Kiss1 expression in the ARC and the AVPV. Kiss1 expression was examined by in situ hybridization in both male and female hamsters kept in various experimental conditions, and we observed that 1) SD exposure markedly reduced Kiss1 expression in the ARC and AVPV of male and female hamsters...... as compared to LD animals, 2) sex steroid treatment in SD-adapted male and female hamsters increased the number of Kiss1 neurons in the AVPV but decreased it in the ARC, 3) melatonin administration to LD-adapted hamsters decreased Kiss1 mRNA level in both the AVPV and the ARC in intact animals, whereas...

  18. Andrographolide Ameliorates Beta-Naphthoflavone-Induced CYP1A Enzyme Activity and Lipid Peroxidation in Hamsters with Acute Opisthorchiasis.

    Science.gov (United States)

    Udomsuk, Latiporn; Chatuphonprasert, Waranya; Jarukamjorn, Kanokwan; Sithithaworn, Paiboon

    2016-01-01

    Opisthorchis viverrini (OV) infection generates oxidative stress/free radicals and is considered as a primary cause ofcholangiocarcinoma since it primarily triggers sclerosing cholangitis. In this study, the impacts of andrographolide on acute opisthorchaisis in β-naphthoflavone (BNF)-exposed hamsters were investigated. Ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-demethylase (MROD) activities and Thiobarbituric acid reaction substances (TBARS) assay of andrographolide in acute opisthorchiasis in the BNF-exposed hamsters were assessed. The results showed that andrographolide ameliorated the hepatic CYP1A1 and CYP1A2 activities by decreases of the specific enzymatic reactions of EROD and MROD, respectively, in the BNF-exposed hamsters. Moreover, andrographolide lowered the formation of malondialdehyde in the livers and brains of the hamsters. These observations revealed the promising chemo-protective and antioxidant activities of andrographolide via suppression of the specific EROD and MROD reactions and lipid peroxidation against acute opisthorchiasis in the BNF-exposed hamsters.

  19. A longitudinal study on BIO14.6 hamsters with dilated cardiomyopathy: micro-echocardiographic evaluation

    Directory of Open Access Journals (Sweden)

    Belfiore Maria

    2011-12-01

    Full Text Available Abstract Background In recent years, several new technologies for small-animal imaging have been developed. In particular, the use of ultrasound in animal imaging has focused on the investigation of accessible biological structures such as the heart, of which it provides a morphological and functional assessment. The purpose of this study was to investigate the role of micro-ultrasonography (μ-US in a longitudinal study on BIO14.6 cardiomyopathic hamsters treated with gene therapy. Methods Thirty hamsters were divided into three groups (n = 10: Group I, untreated BIO 14.6 hamsters; Group II, BIO 14.6 hamsters treated with gene therapy; Group III, untreated wild type (WT hamsters. All hamsters underwent serial μ-US sessions and were sacrificed at predetermined time points. Results μ-US revealed: in Group I, progressive dilation of the left ventricle with a change in heart morphology from an elliptical to a more spherical shape, altered configuration of the mitral valve and subvalvular apparatus, and severe reduction in ejection fraction; in Group II, mild decrease in contractile function and ejection fraction; in Group III, normal cardiac chamber morphology and function. There was a negative correlation between the percentage of fibrosis observed at histology and the ejection fraction obtained on μ-echocardiography (Spearman r: -0.839; p Conclusions Although histological examination remains indispensable for a conclusive diagnosis, high-frequency μ-echocardiography, thanks to the high spatial and contrast resolution, can be considered sufficient for monitoring therapeutic efficacy and/or the progression of dilated cardiomyopathy, providing an alternative tool for repeatable and noninvasive evaluation.

  20. Species difference between rat and hamster in tissue accumulation of mercury after administration of methylmercury

    International Nuclear Information System (INIS)

    Omata, Saburo; Kasama, Hidetaka; Hasegawa, Hiroshi; Hasegawa, Kazuhiro; Sugano, Hiroshi; Ozaki, Kunio

    1986-01-01

    The accumulation of mercury in tissues of the rat and hamster was determined after the administration of a single dose of 203 Hg-methylmercury chloride (10 mg/kg body weight). (1) On day 2, the mercury contents of hamster tissues were higher than those of rat tissues, except for red blood cells, in which the mercury content was about 6-fold higher in the rat than in the hamster. (2) After that time, the mercury content of hamster tissues decreased rather steeply and on day 16 it had reached 14-25% in nervous tissues and 7-15% in other tissues, of the levels on day 2. (3) In the rat, on the other hand, the mercury content of nervous tissues on day 16 was higher than that on day 2 (106-220%), except for dorsal roots and dorsal root ganglia, which showed slight decreases (75-94% of the levels on day 2). In non-neural tissues, the decreases up to day 16 were also small (71-92% of the levels on day 2). (4) Thus, both the uptake and elimination of mercury seem to be more rapid in the tissues of hamster compared with those of the rat. Similar trends of mercury accumulation and elimination were observed when animals received multiple injections of methylmercury that induced acute methylmercury intoxication. (5) Significant biotransmormation of the injected methylmercury to inorganic mercury was detected in the liver, kidney and spleen of both animal species. Although the percentages of inorganic mercury in these tissues wer not so different between the two species on day 2, they became exceedingly high in the tissues of hamster at the later stage, except in the kidney cytosol, in which the values were close in both animal species between day 2 and day 16. (orig.)

  1. Elk3 from hamster-a ternary complex factor with strong transcriptional repressor activity

    DEFF Research Database (Denmark)

    Hjortoe, G.M.; Weilguny, D.; Willumsen, Berthe Marie

    2005-01-01

    the transcription of genes that are activated during entry into G1. We have isolated the Cricetulus griseus Elk3 gene from the Chinese hamster ovary (CHO) cell line and investigated the transcriptional potential of this factor. Transient transfections revealed that, in addition to its regulation of the c......-fos promoter, Elk3 from CHO cells seems to inhibit other promoters controlling expression of proteins involved in G1/S phase progression; Cyclin D1 and DHFR. As has been described for the Elk3 homologs Net (Mouse) and Sap-2 (Human), the results of the present study further indicate that hamster Elk3...

  2. Characterization of Chinese Hamster Ovary Cells Producing Coagulation Factor VIII Using Multi-omics Tools

    DEFF Research Database (Denmark)

    Kaas, Christian Schrøder

    The first public draft of a genome from Chinese hamster ovary (CHO) cells was published in 2011, an entire decade after the first draft of the human genome. This publication of a relevant CHO reference genome, in combination with the fact that the cost for DNA sequencing has dropped more than 10...... hamster origin. The transcriptome of 14 clones producing a dynamic range of FVIII was analyzed using RNA sequencing revealing an unexpected degree of 5’ truncations of the transgene in 11 of the 14 clones. These truncations were validated using targeted genome sequencing, which also mapped the transgene...

  3. Model-based analysis of N-glycosylation in Chinese hamster ovary cells

    DEFF Research Database (Denmark)

    Krambeck, Frederick J.; Bennun, Sandra V; Andersen, Mikael Rørdam

    2017-01-01

    in glycan structure. In this study we utilize an updated version of this model to provide a comprehensive analysis of N-glycosylation in ten Chinese hamster ovary (CHO) cell lines that include a wild type parent and nine mutants of CHO, through interpretation of previously published mass spectrometry data......The Chinese hamster ovary (CHO) cell is the gold standard for manufacturing of glycosylated recombinant proteins for production of biotherapeutics. The similarity of its glycosylation patterns to the human versions enable the products of this cell line favorable pharmacokinetic properties and lower...

  4. Boron neutron capture therapy for the treatment of oral cancer in the hamster cheek pouch model

    International Nuclear Information System (INIS)

    Kreimann, Erica L.; Itoiz, Maria E.; Schwint, Amanda E.; Longhino, Juan; Blaumann, Herman; Calzetta, Osvaldo

    2003-01-01

    We have proposed and validated the hamster cheek pouch model of oral cancer for BNCT studies separately. We herein report the first evidence of the usefulness of BNCT for the treatment of oral cancer in an experimental model. We assessed the response of hamster cheek pouch tumors, precancerous tissue and normal oral tissue to BPA-mediated BNCT employing the thermalized epithermal beam of the RA-6 Reactor at the Bariloche Atomic Center. BNCT leads to complete remission by 15 days post-treatment in 78% of tumors and partial remission in a further 13% of tumors with virtually no damage to normal tissue. (author)

  5. Functional cooperation of xenoproteins after hamster-to-rat liver transplantation: With particular reference to hamster C3 and secretory component for rat IgA

    OpenAIRE

    Celli, S.; Valdivia, L.A.; Kelly, R.H.; Demetris, A.J.; Fung, J.J.; Rao, A.S.; Pan, F.; Tsugita, M.; Starzl, T.E.

    1995-01-01

    Long-term survival after hamster-to-rat liver xenotransplantation has provided the opportunity to study the posttransplantation source of major serum proteins and the functional consequences of several different receptor-ligand interactions, where one or the other is a xenogeneic protein. We report here that serum albumin, α-1-antitrypsin, complement component 3, and other acute phase reactants switch from recipient to donor origin during the first week after transplantation while serum immun...

  6. Maternal Programming of Body Weight in Syrian Hamsters.

    Science.gov (United States)

    Brozek, Jeremy M; Schneider, Jill E; Rhinehart, Erin

    2017-12-01

    Maternal programming of offspring energy balance has been viewed as an adaptation in which the gestational environment prepares the offspring to thrive and reproduce in that same postnatal environment. Programming might have the opposite effect, however, when gestational and postnatal environments are mismatched. Gestational programming would represent a trade-off if the mother can maximize fitness in one possible energetic future but cannot maximize fitness in another. The vast majority of research concerns rats, mice, or sheep, and dams are typically food restricted by 30-70% of ad libitum intake resulting in low birth weight and adult obesity in offspring. Few previous studies have used a lower level of food restriction, and no experiments, to the best of our knowledge, were designed to determine whether the effects of gestational restriction have postgestational effects independent of the effects that occurred during gestation. In the present experiment, Syrian hamsters were either restricted to 90% of their ad libitum food intake or fed ad libitum during pregnancy. All litters were cross-fostered at birth and all were fed ad libitum during lactation. Half of the litters from ad libitum-fed pregnant dams were fostered to dams that had been food restricted during pregnancy and half of the litters from food-restricted pregnant dams were fostered to ad libitum-fed dams. The latter group allowed us to test the hypothesis that the effects of having a gestationally food-restricted mother affects offspring characteristics independent of the prenatal programming. First, we found significant increases in the postnatal body weight of the offspring of ad libitum-fed mothers fostered to food-restricted dams, supporting the hypothesis that the effects of gestational restriction carry over to postnatal maternal ability (e.g., milk yield, milk content, or parental behavior). Second, the carry-over effects of gestational food restriction on offspring postnatal body weight were

  7. Sleep deprivation and daily torpor impair object recognition in Djungarian hamsters

    NARCIS (Netherlands)

    Palchykova, S; Crestani, F; Meerlo, P; Tobler, Irene

    2006-01-01

    Sleep has been shown to play a facilitating role in memory consolidation, whereas sleep deprivation leads to performance impairment both in humans and rodents. The effects of 4-h sleep deprivation on recognition memory were investigated in the Djungarian hamster (Phodopus sungorus). Because sleep

  8. Trends and approaches in N-Glycosylation engineering in Chinese hamster ovary cell culture

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    Chinese hamster ovary (CHO) cells have become the preferred expression system for the production of complex recombinantglycoproteins. It has been historically successful in industrial scale-up application and in generating human-like protein glycosylation.N-glycosylation of recombinant proteins...

  9. Induction of Atherosclerosis in Mice and Hamsters Without Germline Genetic Engineering

    DEFF Research Database (Denmark)

    Bjørklund, Martin Mæng; Hollensen, Anne K; Hagensen, Mette K

    2014-01-01

    of this approach for creating atherosclerosis models also in nonmurine species was demonstrated by inducing hypercholesterolemia and early atherosclerosis in Golden Syrian hamsters. CONCLUSIONS: Single injections of proprotein convertase subtilisin/kexin type 9-encoding recombinant adeno-associated viral vectors...

  10. Temporal organization of feeding in Syrian hamsters with a genetically altered circadian period

    NARCIS (Netherlands)

    Oklejewicz, M; Overkamp, GJF; Stirland, JA; Daan, S

    2001-01-01

    The variation in spontaneous meal patterning was studied in three genotypes (tau +/+, tau +/- and tau -/-) of the Syrian hamster with an altered circadian period. Feeding activity was monitored continuously in 13 individuals from each genotype in constant dim light conditions. All three genotypes

  11. The genomic sequence of the Chinese hamster ovary (CHO)-K1 cell line

    DEFF Research Database (Denmark)

    Xu, Xun; Pan, Shengkai; Liu, Xin

    2011-01-01

    Chinese hamster ovary (CHO)-derived cell lines are the preferred host cells for the production of therapeutic proteins. Here we present a draft genomic sequence of the CHO-K1 ancestral cell line. The assembly comprises 2.45 Gb of genomic sequence, with 24,383 predicted genes. We associate most...

  12. Differential cytokine gene expression according to outcome in a hamster model of leptospirosis.

    Directory of Open Access Journals (Sweden)

    Frédérique Vernel-Pauillac

    Full Text Available BACKGROUND: Parameters predicting the evolution of leptospirosis would be useful for clinicians, as well as to better understand severe leptospirosis, but are scarce and rarely validated. Because severe leptospirosis includes septic shock, similarities with predictors evidenced for sepsis and septic shock were studied in a hamster model. METHODOLOGY/PRINCIPAL FINDINGS: Using an LD50 model of leptospirosis in hamsters, we first determined that 3 days post-infection was a time-point that allowed studying the regulation of immune gene expression and represented the onset of the clinical signs of the disease. In the absence of tools to assess serum concentrations of immune effectors in hamsters, we determined mRNA levels of various immune genes, especially cytokines, together with leptospiraemia at this particular time-point. We found differential expression of both pro- and anti-inflammatory mediators, with significantly higher expression levels of tumor necrosis factor alpha, interleukin 1alpha, cyclo-oxygenase 2 and interleukin 10 genes in nonsurvivors compared to survivors. Higher leptospiraemia was also observed in nonsurvivors. Lastly, we demonstrated the relevance of these results by comparing their respective expression levels using a LD100 model or an isogenic high-passage nonvirulent variant. CONCLUSIONS/SIGNIFICANCE: Up-regulated gene expression of both pro- and anti-inflammatory immune effectors in hamsters with fatal outcome in an LD50 model of leptospirosis, together with a higher Leptospira burden, suggest that these gene expression levels could be predictors of adverse outcome in leptospirosis.

  13. Toward genome-scale models of the Chinese hamster ovary cells: incentives, status and perspectives

    DEFF Research Database (Denmark)

    Kaas, Christian Schrøder; Fan, Yuzhou; Weilguny, Dietmar

    2014-01-01

    Bioprocessing of the important Chinese hamster ovary (CHO) cell lines used for the production of biopharmaceuticals stands at the brink of several redefining events. In 2011, the field entered the genomics era, which has accelerated omics-based phenotyping of the cell lines. In this review we...

  14. Seasonal adaption of dwarf hamsters (Genus Phodopus): differences between species and their geographic origin

    Czech Academy of Sciences Publication Activity Database

    Müller, D.; Hauer, J.; Schöttner, Konrad; Fritzsche, P.; Weinert, D.

    2015-01-01

    Roč. 185, č. 8 (2015), s. 917-930 ISSN 0174-1578 Institutional support: RVO:60077344 Keywords : dwart hamsters * photoperiodism * critical photoperiod Subject RIV: ED - Physiology Impact factor: 1.884, year: 2015 http://link.springer.com/article/10.1007%2Fs00360-015-0926-4

  15. Maternal and pup genotype contribution to growth in wild-type and tau mutant Syrian hamsters

    NARCIS (Netherlands)

    Oklejewicz, Malgorzata; Pen, Ido; Durieux, Geesje C.R.; Daan, Serge

    The single gene mutation tau in the Syrian hamster-apart from its effect on the circadian organization of locomotor activity-has a pronounced influence on body weight. In this study we investigate the impact of maternal and pup genotypes at the tau-locus on the growth rate of pups. Homozygous tau

  16. Analysis of Ca and Mg in blood of golden hamster using NAA technique

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Rodrigo O.; Zamboni, Cibele B.; Medeiros, Jose A.G. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil)], e-mail: rodrigoaguiar@usp.br, e-mail: czamboni@ipen.br, e-mail: jageiros@yahoo.com.br

    2009-07-01

    Neutron activation analysis (NAA) technique has been used to determine simultaneously Ca and Mg concentrations in whole blood of Golden Hamster. The reference values for Ca (0.17 - 0.29 gL{sup -1} ) and Mg (0.042 - 0.074 gL{sup -1} ) can be used to performed biochemistry investigation using whole blood. (author)

  17. Versatile microscale screening platform for improving recombinant protein productivity in Chinese hamster ovary cells

    DEFF Research Database (Denmark)

    Hansen, Henning Gram; Nilsson, Claes Nymand; Lund, Anne Mathilde

    2015-01-01

    Chinese hamster ovary (CHO) cells are widely used as cell factories for the production of biopharmaceuticals. In contrast to the highly optimized production processes for monoclonal antibody (mAb)-based biopharmaceuticals, improving productivity of non-mAb therapeutic glycoproteins is more likely...

  18. Partial synchronization of spermatogenesis in the immature Djungarian hamster, but not in the immature Wistar rat

    NARCIS (Netherlands)

    van Haaster, L. H.; de rooij, D. G.

    1994-01-01

    The frequencies of the cellular associations of the seminiferous epithelium were determined at various ages after birth in immature Djungarian hamsters and Wistar rats. The frequencies of the cellular associations present in immature animals were then compared with the frequencies of the

  19. The genomic sequence of the Chinese hamster ovary (CHO)-K1 cell line

    DEFF Research Database (Denmark)

    Xu, Xun; Pan, Shengkai; Liu, Xin

    2011-01-01

    Chinese hamster ovary (CHO)-derived cell lines are the preferred host cells for the production of therapeutic proteins. Here we present a draft genomic sequence of the CHO-K1 ancestral cell line. The assembly comprises 2.45 Gb of genomic sequence, with 24,383 predicted genes. We associate most of...

  20. In vitro and in vivo studies evaluating antisemen antibodies as a potential spermicidal agent in hamsters.

    Science.gov (United States)

    Chen, De-Yu; Liu, Li-Min; Xie, Qing-Dong; Xu, Lan; Huang, Tian-Hua

    2009-09-01

    To determine the spermicidal activity of antisemen antibodies in the hamster model. Prospective, controlled study. Advanced preclinical sciences center. Subgroups of 10 and 14 golden hamsters. Ex vitro and in vivo treatment of sperm with antisemen antibodies or normal rabbit serum. The EC(50) value of antisemen antibodies, the time required for 50% motility loss of progressively motile spermatozoa exposed to antisemen antibodies, the average sperm mitochondrion fluorescence intensity, the rate of fertilization, and the scoring of histologic changes in the hamster vaginal tissue. The EC(50) value of antisemen antibodies was found 70 microg/mL, and the time required for 50% motility loss of progressively motile spermatozoa exposed to antisemen antibodies (at 70 microg/mL) was 5 minutes; for the experimental and control groups, the average fluorescence intensities of sperm mitochondria were respectively 180.28 +/- 82.24 and 309.74 +/- 148.37, the fertilization rates in vitro were 0.09% and 45%, the rates of fertilization with intrauterine sperm injection were 0 and 15.0%. There was a significant difference between two groups. None of the four hamsters that received antisemen antibodies in gel-polyoxyl-40-stearate had epithelial disruption characteristic of inflammation. Antisemen antibodies possess appreciable spermicidal potential, which may be explored as an effective constituent of spermicide.

  1. Differential effect of lithium on the circadian oscillator in young and old hamsters

    International Nuclear Information System (INIS)

    Iwahana, Eiko; Hamada, Toshiyuki; Uchida, Ayumi; Shibata, Shigenobu

    2007-01-01

    Lithium is one of the most commonly used drugs in the prophylaxis and treatment of bipolar disorder. It is also known to lengthen circadian period in several organisms. Previously, we reported that there was the association between lengthening circadian period by lithium and GSK-3 protein and its enzyme activity in the mouse suprachiasmatic nucleus (SCN). In this study, we show that lithium affects the circadian oscillator in young and old hamster SCN, in an age-dependent manner. We found that basal levels of phosphorylated GSK-3 (pGSK-3) protein expression in old hamsters are much lower than that in young hamsters. Furthermore, in the old hamsters, lithium did not affect the period of the locomotor activity rhythm or pGSK-3 expression, while changing period and pGSK-3 in the younger animals. These results indicate that the content of pGSK-3 in the SCN has an important role in age-dependent effects of lithium on the circadian oscillator

  2. 9 CFR 3.36 - Primary enclosures used to transport live guinea pigs and hamsters.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Primary enclosures used to transport live guinea pigs and hamsters. 3.36 Section 3.36 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE STANDARDS Specifications for the Humane Handling, Care, Treatment, and Transportation of...

  3. Development of Hamster Models for Acute and Chronic Infections with Leptospira borgpetersenii serovar Hardjo

    Science.gov (United States)

    The Golden Syrian hamster is frequently used as a small animal model to study acute leptospirosis. However, use of this small animal model to study Leptospira borgpetersenii serovar Hardjo infections has not been well documented. Cattle are the normal maintenance hosts of L. borgpetersenii serovar...

  4. Estrogen accelerates gonadal recrudescence in photo-regressed male siberian hamsters.

    Science.gov (United States)

    Pak, Toni R; Lynch, G Robert; Tsai, Pei-San

    2002-10-01

    Seasonal gonadal recrudescence in the male Siberian hamster is accompanied by the initiation of spermatogenesis, weight gain, and darkening of coat color. The downstream endocrine regulators responsible for these changes have been definitively identified. We have previously shown that the administration of exogenous 17beta-estradiol (E(2)) to adult male Siberian hamsters kept under long-day photoperiod increased testicular mass without altering spermatogenesis. In this study, we examine if E(2) can initiate testicular growth in photo-regressed adult Siberian hamsters and if this testicular growth is accompanied by weight gain and pelage color change. Photo-regressed adult male Siberian hamsters were subcutaneously implanted with a 1 mm silastic capsule containing E(2) or cholesterol control. After 15 days, robust initiation of spermatogenesis was observed in E(2)-implanted animals in the absence of body weight and pelage color change. While circulating follicle-stimulating hormone (FSH) remained undetected in both control and E(2)-treated animals, E(2) significantly reduced pituitary gonadotropin stores. Overall, we showed E(2) stimulated gonadal recrudescence via a pathway that has diverged from body weight and pelage color change. Further, we demonstrated a novel role of E(2) in the initiation of spermatogenesis, possibly via a mechanism independent of FSH.

  5. Inhibition of DMBA carcinogenesis of hamster buccal pouch by phenanthrene and dimethylnaphthalene.

    Science.gov (United States)

    Malament, D S; Shklar, G

    1981-01-01

    Phenanthrene (Phe) and to a lesser degree 1,4-dimethylnaphthalene (DMeN) were each found to retard the development of epidermoid carcinomas in hamster buccal pouch induced by the thrice weekly application of a 0.5 per cent solution of 7,12-dimethylbenz[a]anthracene (DMBA) in heavy mineral oil.

  6. The precision of circadian clocks : Assessment and analysis in Syrian hamsters

    NARCIS (Netherlands)

    Daan, S; Oklejewicz, M

    2003-01-01

    Locomotor activity recordings of Syrian hamsters were systematically analyzed to estimate the precision of the overt circadian activity rhythm in constant darkness. Phase variation, i.e., the standard deviation of phase markers around the regression line, varied with the definition of phase.

  7. Vascular Anatomy of the Hamster Retractor Muscle with Regard to Its Microvascular Transfer.

    NARCIS (Netherlands)

    de With, M.C.J.; Vries, A.M.; Kroese, A.B.A.|info:eu-repo/dai/nl/068352247; van der Heijden, E.P.A.; Bleys, R.L.A.W.; Segal, S.S.; Kon, M.

    2009-01-01

    BACKGROUND: The hamster retractor muscle (RET) is used as an in vivo model in studies of skeletal muscle ischemia-reperfusion injury. The RET is unique in that the muscle can be isolated while preserving the primary vascular supply so that its contractile function can be measured simultaneously with

  8. Trends and approaches in N-Glycosylation engineering in Chinese hamster ovary cell culture

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    Chinese hamster ovary (CHO) cells have become the preferred expression system for the production of complex recombinantglycoproteins. It has been historically successful in industrial scale-up application and in generating human-like protein glycosylation.N-glycosylation of recombinant proteins......) omics-based characterization, 6) mathematical modelling....

  9. The adaptive immune response does not influence hantavirus disease or persistence in the Syrian hamster

    Science.gov (United States)

    Prescott, Joseph; Safronetz, David; Haddock, Elaine; Robertson, Shelly; Scott, Dana; Feldmann, Heinz

    2013-01-01

    Pathogenic New World hantaviruses cause severe disease in humans characterized by a vascular leak syndrome, leading to pulmonary oedema and respiratory distress with case fatality rates approaching 40%. Hantaviruses infect microvascular endothelial cells without conspicuous cytopathic effects, indicating that destruction of the endothelium is not a mechanism of disease. In humans, high levels of inflammatory cytokines are present in the lungs of patients that succumb to infection. This, along with other observations, suggests that disease has an immunopathogenic component. Currently the only animal model available to study hantavirus disease is the Syrian hamster, where infection with Andes virus (ANDV), the primary agent of disease in South America, results in disease that closely mimics that seen in humans. Conversely, inoculation of hamsters with a passaged Sin Nombre virus (SNV), the virus responsible for most cases of disease in North America, results in persistent infection with high levels of viral replication. We found that ANDV elicited a stronger innate immune response, whereas SNV elicited a more robust adaptive response in the lung. Additionally, ANDV infection resulted in significant changes in the blood lymphocyte populations. To determine whether the adaptive immune response influences infection outcome, we depleted hamsters of CD4+ and CD8+ T cells before infection with hantaviruses. Depletion resulted in inhibition of virus-specific antibody responses, although the pathogenesis and replication of these viruses were unaltered. These data show that neither hantavirus replication, nor pathogenesis caused by these viruses, is influenced by the adaptive immune response in the Syrian hamster. PMID:23600567

  10. Characterization of diethylnitrosamine-induced liver carcinogenesis in Syrian golden hamsters

    Science.gov (United States)

    CHEN, GUO; DAI, ZHI-KAI; LIANG, RONG-GAN; XIAO, SHENG-JUN; HE, SONG-QING; ZHAO, HAI-LU; XU, QING

    2012-01-01

    The aim of this study was to characterize hepatocarcinogenesis in diethylnitrosamine (DEN)-treated hamsters. Syrian golden hamsters (n=36) were administered DEN by hypodermic injection and addition to drinking water. Morphological analyses, including light microscopy and immunohistochemistry of α-fetal protein (AFP), were performed on liver and lung tissues. Primary cell culture and tumor transplantation were carried out to evaluate the potential application in hepatocellular carcinoma (HCC) research. From 25 to 50 weeks of treatment, liver tumors, including macronodular HCC and ascites, were found in one-third (4/12) of the animals treated with DEN. HCC was characterized by poor differentiation, frequent mitosis, AFP reaction, vessel invasion and potential application in primary cell culture and xenotransplantation. Pre-neoplastic lesions were hyperplastic nodules comprised of clear cells, bile duct proliferation, fatty metamorphosis and multilocular cysts. The DEN-treated hamsters also showed lung tumors consisting of AFP-negative, well-differentiated neoplastic cells. Characterization of DEN-induced HCC in hamsters provides insights into human hepatocarcinogenesis. This animal model has potential applications in HCC research. PMID:22969883

  11. Pineal melatonin is a circadian time-giver for leptin rhythm in Syrian hamsters

    Directory of Open Access Journals (Sweden)

    Ibtissam eChakir

    2015-05-01

    Full Text Available Nocturnal secretion of melatonin from the pineal gland may affect central and peripheral timing, in addition to its well-known involvement in the control of seasonal physiology. The Syrian hamster is a photoperiodic species, which displays gonadal atrophy and increased adiposity when adapted to short (winter-like photoperiods. Here we investigated whether pineal melatonin secreted at night can impact daily rhythmicity of metabolic hormones and glucose in that seasonal species. For that purpose, daily variations of plasma leptin, cortisol, insulin and glucose were analyzed in pinealectomized hamsters, as compared to sham-operated controls kept under very long (16h light/08h dark or short photoperiods (08h light/16h dark. Daily rhythms of leptin under both long and short photoperiods were blunted by pinealectomy. Furthermore, the phase of cortisol rhythm under a short photoperiod was advanced by 5.6 h after pinealectomy. Neither plasma insulin, nor blood glucose displays robust daily rhythmicity, even in sham-operated hamsters. Pinealectomy, however, totally reversed the decreased levels of insulin under short days and the photoperiodic variations in mean levels of blood glucose (i.e., reduction and increase in long and short days, respectively. Together, these findings in Syrian hamsters show that circulating melatonin at night drives the daily rhythmicity of plasma leptin, participates in the phase control of cortisol rhythm and modulates glucose homeostasis according to photoperiod-dependent metabolic state.

  12. Thermotelemetric study on the hibernation of a common hamster, Cricetus cricetus (Linnaeus, 1758), under natural circumstances

    NARCIS (Netherlands)

    Gubbels, R.E.M.B.; Gelder, van J.J.; Lenders, A.

    1989-01-01

    By means of radio-thermotelemetry a study was made of the thermoregulatory patterns during hibernation of a common hamster, Cricetus cricetus (L., 1758) under natural conditions. In the euthermic state, body temperature (Tb) fluctuated between 36.4 and 38.6°C with Tb higher than 37.0°C probably

  13. Temporal organisation of hibernation in wild-type and tau mutant Syrian hamsters

    NARCIS (Netherlands)

    Oklejewicz, M; Daan, S; Strijkstra, AM; Heldmaier, G.

    The temporal pattern of hibernation was studied in three genotypes of Syrian hamsters with different circadian periodicity to assess a potential circadian control of alternating torpor and euthermy. We recorded the pattern of hibernation by measuring activity in continuous dim light and constant

  14. Basking hamsters reduce resting metabolism, body temperature and energy costs during rewarming from torpor.

    Science.gov (United States)

    Geiser, Fritz; Gasch, Kristina; Bieber, Claudia; Stalder, Gabrielle L; Gerritsmann, Hanno; Ruf, Thomas

    2016-07-15

    Basking can substantially reduce thermoregulatory energy expenditure of mammals. We tested the hypothesis that the largely white winter fur of hamsters (Phodopus sungorus), originating from Asian steppes, may be related to camouflage to permit sun basking on or near snow. Winter-acclimated hamsters in our study were largely white and had a high proclivity to bask when resting and torpid. Resting hamsters reduced metabolic rate (MR) significantly (>30%) when basking at ambient temperatures (Ta) of ∼15 and 0°C. Interestingly, body temperature (Tb) also was significantly reduced from 34.7±0.6°C (Ta 15°C, not basking) to 30.4±2.0°C (Ta 0°C, basking), which resulted in an extremely low (thermal conductance. Induced torpor (food withheld) during respirometry at Ta 15°C occurred on 83.3±36.0% of days and the minimum torpor MR was 36% of basal MR at an average Tb of 22.0±2.6°C; movement to the basking lamp occurred at Tb50%) during radiant heat-assisted rewarming; however, radiant heat per se without an endogenous contribution by animals did not strongly affect metabolism and Tb during torpor. Our data show that basking substantially modifies thermal energetics in hamsters, with a drop of resting Tb and MR not previously observed and a reduction of rewarming costs. The energy savings afforded by basking in hamsters suggest that this behaviour is of energetic significance not only for mammals living in deserts, where basking is common, but also for P. sungorus and probably other cold-climate mammals. © 2016. Published by The Company of Biologists Ltd.

  15. Effects of unsaturated fatty acids on torpor frequency and diet selection in Djungarian hamsters (Phodopus sungorus).

    Science.gov (United States)

    Diedrich, Victoria; Steinlechner, Stephan; Scherbarth, Frank

    2014-12-15

    Essential polyunsaturated fatty acids (PUFA) have been shown to play a beneficial role in hibernating mammals. High amounts of dietary PUFA led to an earlier hibernation onset, deeper and longer hibernation bouts and a higher proportion of hibernating animals in several species. In contrast, the relevance of dietary PUFA for daily heterotherms exhibiting only brief and shallow torpor bouts is less well studied. Therefore, diets differing in PUFA composition were used to examine the effects on the frequency of spontaneous daily torpor in Djungarian hamsters (Phodopus sungorus). In contrast to earlier studies, we were interested in whether the ratio of n-6 to n-3 PUFA affects torpor expression, and in comparison with a diet rich in monounsaturated fatty acids (MUFA). Although we found a positive effect on torpor frequency in hamsters fed a diet rich in n-6 PUFA compared with the groups fed diets either rich in n-3 PUFA or MUFA, the latter two groups did not show unusually low torpor frequencies. The results of the additional diet choice experiment indicated that hamsters in short photoperiod select food with only a slight excess of n-6 PUFA compared with n-3 PUFA (ratio of 1 to 1.5). However, there was no significant difference in torpor frequency between the diet choice group and hamsters fed on standard chow with a sevenfold excess of n-6 PUFA. In summary, the present data strongly indicate that the dietary composition of unsaturated fatty acids plays a minor role in the occurrence of spontaneous daily torpor in Djungarian hamsters. © 2014. Published by The Company of Biologists Ltd.

  16. Mitochondrial Respiration Is Impaired during Late-Stage Hamster Prion Infection.

    Science.gov (United States)

    Faris, Robert; Moore, Roger A; Ward, Anne; Sturdevant, Dan E; Priola, Suzette A

    2017-09-15

    Mitochondria are crucial to proper neuronal function and overall brain health. Mitochondrial dysfunction within the brain has been observed in many neurodegenerative diseases, including prion disease. Several markers of decreased mitochondrial activity during prion infection have been reported, yet the bioenergetic respiratory status of mitochondria from prion-infected animals is unknown. Here we show that clinically ill transgenic mice overexpressing hamster prion protein (Tg7) infected with the hamster prion strain 263K suffer from a severe deficit in mitochondrial oxygen consumption in response to the respiratory complex II substrate succinate. Characterization of the mitochondrial proteome of purified brain mitochondria from infected and uninfected Tg7 mice showed significant differences in the relative abundance of key mitochondrial electron transport proteins in 263K-infected animals relative to that in controls. Our results suggest that at clinical stages of prion infection, dysregulation of respiratory chain proteins may lead to impairment of mitochondrial respiration in the brain. IMPORTANCE Mitochondrial dysfunction is present in most major neurodegenerative diseases, and some studies have suggested that mitochondrial processes may be altered during prion disease. Here we show that hamster prion-infected transgenic mice overexpressing the hamster prion protein (Tg7 mice) suffer from mitochondrial respiratory deficits. Tg7 mice infected with the 263K hamster prion strain have little or no signs of mitochondrial dysfunction at the disease midpoint but suffer from a severe deficit in mitochondrial respiration at the clinical phase of disease. A proteomic analysis of the isolated brain mitochondria from clinically affected animals showed that several proteins involved in electron transport, mitochondrial dynamics, and mitochondrial protein synthesis were dysregulated. These results suggest that mitochondrial dysfunction, possibly exacerbated by prion protein

  17. VGF-derived peptide, TLQP-21, regulates food intake and body weight in Siberian hamsters.

    Science.gov (United States)

    Jethwa, Preeti H; Warner, Amy; Nilaweera, Kanishka N; Brameld, John M; Keyte, John W; Carter, Wayne G; Bolton, Neil; Bruggraber, Michael; Morgan, Peter J; Barrett, Perry; Ebling, Francis J P

    2007-08-01

    The Siberian hamster survives winter by decreasing food intake and catabolizing abdominal fat reserves, resulting in a sustained, profound loss of body weight. VGF gene expression is photoperiodically regulated in the hypothalamus with significantly higher expression in lean Siberian hamsters. The aim of this study was to investigate the role of VGF in regulating these seasonal cycles by determining the effects of a VGF-derived peptide (TLQP-21) on food intake and body weight. Acute intracerebroventricular administration of TLQP-21 decreased food intake, and chronic treatment caused a sustained reduction in food intake and body weight and decreased abdominal fat depots. Behavioral analysis revealed that TLQP-21 reduced meal size but not the frequency of feeding bouts, suggesting a primary action on satiety. Hamsters treated with TLQP-21 lost a similar amount of weight as a pair-fed group in which food intake was matched to that of the TLQP-21-treated group. Central or peripheral treatment with TLQP-21 did not produce a significant effect on resting metabolic rate. We conclude that the primary action of TLQP-21 is to decrease food intake rather than increase energy expenditure. TLQP-21 treatment caused a decrease in UCP-1 mRNA in brown adipose tissue, but hypothalamic expression of orexigenic and anorexigenic neuropeptide genes remained unchanged after TLQP-21 treatment, although compensatory increases in NPY and AgRP mRNA were observed in the pair-fed hamsters. The effects of TLQP-21 administration are similar to those in hamsters in short days, suggesting that increased VGF activity may contribute to the hypophagia that underlies the seasonal catabolic state.

  18. Roles of RFRP-3 in the daily and seasonal regulation of reproductive activity in female Syrian hamsters

    DEFF Research Database (Denmark)

    Henningsen, Jo B.; Ancel, Caroline; Mikkelsen, Jens D.

    2017-01-01

    in female Syrian hamsters by analyzing the RFRP system and investigating the effects of central administration of RFRP-3 at different reproductive stages. In long day-adapted sexually active female hamsters, the number of c-Fos-activated RFRP immunoreactive neurons was reduced in the afternoon of diestrus...... that RFRP-3 exerts a tonic inhibition on LH secretion, which is lifted at the time of the preovulatory surge on the afternoon of proestrus. In short day-adapted sexually inactive female hamsters, Rfrp expression is strongly inhibited in a sex steroid-independent manner, and prolonged central infusion...

  19. Synthesis of human prolactin in Chinese hamster ovary (CHO) cells; Sintese de prolactina humana em celulas de ovario de hamster chines (CHO)

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Carlos Roberto Jorge

    2000-07-01

    Three different eukaryotic expression vectors, based on the same selectable gene marker (dhfr), have been used for dhf- CHO cells transfection to rapidly isolate stable cell lines capable of secreting high levels of recombinant human prolactin (rec-hPRL). Two vectors, one codifying a human prolactin (p658-hPRL) and the other a tag-prolactin (p658-tagPRL), contain the complete hepatitis B virus-X (HBV-X) gene coding for a viral transactivator and a sequence derived from the granulocyte-macrophage colony-stimulating factor (GM-CSF) that mediates selective dhfr mRNA degradation. These vectors have the advantage of rapidly obtaining stable cell lines without methotrexate amplification. The highest secretion obtained by these vectors was of approximately 10 {mu}g hPRU10{sup 6} cells/day. The other vector (pEDdc-hPRL) is based on a dicistronic expression system, containing an internal ribosome entry site isolated from the encephalomyocarditis (EMC) virus. This vector before amplification provided secretion levels at least 10 fold lower than that obtained with the other two vectors. However, after three steps of methotrexate amplification, it provided some clones able to secrete up to 30 {mu}g hPRU10{sup 6} cells/day. This is the first report describing the production and purification of rec-hPRL from CHO cells, obtaining secretion levels with both vectors higher than those reported so far for this hormone in other eukaryotic systems. CHO-derived rec-hPRL contained approximately 10 % of the glycosylated form, a value that is consistent with results reported for hPRL purified from the pituitary or from transformed murine C-127 cells. CHO-derived rec-hPRL was purified with good yield, obtaining also a good resolution between non-glycosylated and glycosylated prolactin. The latter, when its potency was determined via an in vitro bioassay, presented a 47 % lower bioactivity. A qualitative and quantitative analysis of these forms was also possible thanks to the setting up of a reversed-phase HPLC technique, for the first time applied to this hormone. A pilot production in a hollow fiber bioreactor provided a highly concentrated medium, though with the presence of considerable amounts of hPRL{sub 11-199} fragments, apparently the result of a proteolytic process. (author)

  20. Intensive voluntary wheel running may restore circadian activity rhythms and improves the impaired cognitive performance of arrhythmic Djungarian hamsters

    Czech Academy of Sciences Publication Activity Database

    Weinert, D.; Schöttner, Konrad; Müller, L.; Wienke, A.

    2016-01-01

    Roč. 33, č. 9 (2016), s. 1161-1170 ISSN 0742-0528 Institutional support: RVO:60077344 Keywords : Djungarian hamster * circadian rhythm * arrhythmic activity pattern Subject RIV: ED - Physiology Impact factor: 2.562, year: 2016

  1. Mixing of M Segment DNA Vaccines to Hantaan Virus and Puumala Virus Reduces Their Immunogenicity in Hamsters

    National Research Council Canada - National Science Library

    Spik, Kristin W; Badger, Catherine; Mathiessen, Iacob; Tjelle, Torunn; Hooper, Jay W; Schmaljohn, Connie

    2008-01-01

    ... them to hamsters separately or as mixtures by gene gun or by electroporation. Both vaccines elicited neutralizing antibodies when given alone but when they were delivered as a mixture, antibodies to only one of the two hantaviruses could be detected...

  2. Daily timed melatonin feedings mimic effects of short days on testis regression and cortisol in circulation in Siberian hamsters.

    Science.gov (United States)

    Hiebert, Sara M; Green, Stephen A; Yellon, Steven M

    2006-05-01

    This study tested the efficacy of timed oral administration of melatonin as an alternative both to invasive methods (daily injections, timed infusions) and to untimed oral administration in Siberian hamsters (Phodopus sungorus), an important model for the study of photoperiodism. Hamsters readily consumed a small piece of melatonin-treated apple immediately when presented and circulating melatonin was rapidly elevated with a half-life of approximately 3.5 h. Melatonin-treated apple was fed to hamsters for 3 weeks at 2 h before lights off to extend the duration of the nighttime rise in endogenous melatonin. Melatonin treatment induced testicular regression and elevated serum cortisol, effects comparable to those in hamsters exposed to short days. These findings support the hypothesis that timed oral administration of melatonin can mimic the effects of short days and provide a method by which melatonin can be delivered without the potentially confounding effects of handling and injection stress.

  3. Differential regulation of kiss1 expression by melatonin and gonadal hormones in male and female Syrian hamsters

    DEFF Research Database (Denmark)

    Ansel, L; Bolborea, M; Bentsen, A H

    2010-01-01

    ). In rodents, Kiss1 is expressed in the anteroventral periventricular nucleus (AVPV) and in the arcuate nucleus (ARC). Because both the duration of the nocturnal peak of melatonin and circulating sex steroid levels vary with photoperiod, the aim of this study was to determine whether melatonin and sex steroids...... differentially regulate Kiss1 expression in the ARC and the AVPV. Kiss1 expression was examined by in situ hybridization in both male and female hamsters kept in various experimental conditions, and we observed that 1) SD exposure markedly reduced Kiss1 expression in the ARC and AVPV of male and female hamsters...... as compared to LD animals, 2) sex steroid treatment in SD-adapted male and female hamsters increased the number of Kiss1 neurons in the AVPV but decreased it in the ARC, 3) melatonin administration to LD-adapted hamsters decreased Kiss1 mRNA level in both the AVPV and the ARC in intact animals, whereas...

  4. Effects of diazepam on Mycobacterium bovis-induced infection in hamsters

    Directory of Open Access Journals (Sweden)

    Righi D.A.

    1999-01-01

    Full Text Available The in utero exposure of hamsters to low doses of diazepam results in impaired host defense against Mycobacterium bovis during adulthood. Delayed developmental immunotoxicity, however, represents a specific situation that might not be general. The present experiment was undertaken to investigate the effects of diazepam on hamster resistance to M. bovis using adult animals. The effects of diazepam treatment on serum cortisol levels were also studied. Adult hamsters (N = 10 for each group were treated with diazepam (E1 = 1.0, E2 = 2.0 or E3 = 3.0 mg kg-1 day-1 subcutaneously or with control solution (C for 30 days. Seven days after the beginning of the treatment, the animals received identical inoculum concentrations of M. bovis. Hamsters treated with the higher (2.0 and 3.0 mg kg-1 day-1 doses of diazepam exhibited: 1 increased granuloma areas in the liver (C = 1.81 ± 1.39, E2 = 10.29 ± 4.64 and E3 = 15.80 ± 4.82 and lung (C = 0.54 ± 0.55, E2 = 6.28 ± 3.85 and E3 = 6.31 ± 3.56 and 2 increased scores of M. bovis colony-forming units isolated from liver (C = 2.0, E2 = 3.0 and E3 = 3.5, lung (C = 1.0, E2 = 3.0 and E3 = 3.5 and spleen (C = 1.0, E2 = 2.5 and E3 = 4.0. These effects were dose dependent, and were not detected or were less severe in animals treated with the lowest (1.0 mg/kg dose of diazepam as well as in those of the control group. Furthermore, diazepam treatment (3.0 mg kg-1 day-1 for 30 days increased (E3 = 71.32 ± 2.99; N = 10 the serum levels of cortisol compared to control hamsters (C = 22.61 ± 2.75; N = 10. The present data, that demonstrate an impaired defense against M. bovis in adult hamsters treated with diazepam, were tentatively explained on the basis of a direct and/or indirect action of diazepam on the cytokine network. The effects may be related to stimulation of peripheral benzodiazepine receptor binding sites (PBR by macrophages and/or lymphocytes, or they may be mediated by PBR stimulation of the adrenals.

  5. Hypothalamic ventricular ependymal thyroid hormone deiodinases are an important element of circannual timing in the Siberian hamster (Phodopus sungorus.

    Directory of Open Access Journals (Sweden)

    Annika Herwig

    Full Text Available Exposure to short days (SD induces profound changes in the physiology and behaviour of Siberian hamsters, including gonadal regression and up to 30% loss in body weight. In a continuous SD environment after approximately 20 weeks, Siberian hamsters spontaneously revert to a long day (LD phenotype, a phenomenon referred to as the photorefractory response. Previously we have identified a number of genes that are regulated by short photoperiod in the neuropil and ventricular ependymal (VE cells of the hypothalamus, although their importance and contribution to photoperiod induced physiology is unclear. In this refractory model we hypothesised that the return to LD physiology involves reversal of SD expression levels of key hypothalamic genes to their LD values and thereby implicate genes required for LD physiology. Male Siberian hamsters were kept in either LD or SD for up to 39 weeks during which time SD hamster body weight decreased before increasing, after more than 20 weeks, back to LD values. Brain tissue was collected between 14 and 39 weeks for in situ hybridization to determine hypothalamic gene expression. In VE cells lining the third ventricle, expression of nestin, vimentin, Crbp1 and Gpr50 were down-regulated at 18 weeks in SD photoperiod, but expression was not restored to the LD level in photorefractory hamsters. Dio2, Mct8 and Tsh-r expression were altered by SD photoperiod and were fully restored, or even exceeded values found in LD hamsters in the refractory state. In hypothalamic nuclei, expression of Srif and Mc3r mRNAs was altered at 18 weeks in SD, but were similar to LD expression values in photorefractory hamsters. We conclude that in refractory hamsters not all VE cell functions are required to establish LD physiology. However, thyroid hormone signalling from ependymal cells and reversal of neuronal gene expression appear to be essential for the SD refractory response.

  6. Improving the secretory capacity of Chinese hamster ovary cells by ectopic expression of effector genes: Lessons learned and future directions

    DEFF Research Database (Denmark)

    Hansen, Henning Gram; Pristovsek, Nusa; Kildegaard, Helene Faustrup

    2017-01-01

    Chinese hamster ovary (CHO) cells are the preferred cell factory for the production of therapeutic glycoproteins. Although efforts primarily within bioprocess optimization have led to increased product titers of recombinant proteins (r-proteins) expressed in CHO cells, post-transcriptional bottle......Chinese hamster ovary (CHO) cells are the preferred cell factory for the production of therapeutic glycoproteins. Although efforts primarily within bioprocess optimization have led to increased product titers of recombinant proteins (r-proteins) expressed in CHO cells, post...

  7. Identification of a single chromosome in the normal human genome essential for suppression of hamster cell transformation.

    OpenAIRE

    Stoler, A; Bouck, N

    1985-01-01

    Normal human fibroblasts were fused to carcinogen-transformed baby hamster kidney (BHK) cells and found to be able to suppress the anchorage-independent transformed phenotype of the hamster cells. This suppression was not due to interspecies incompatibility, for transformation could be effectively expressed in hybrids if either the human or the BHK parent had initially been transformed by a dominantly acting viral genome. Upon growth of suppressed hybrids, loss of human chromosomes was accomp...

  8. Differential regulation of kiss1 expression by melatonin and gonadal hormones in male and female Syrian hamsters

    DEFF Research Database (Denmark)

    Ansel, L; Bolborea, M; Bentsen, A H

    2010-01-01

    In seasonal breeders, reproduction is synchronized to seasons by day length via the pineal hormone melatonin. Recently, we have demonstrated that Kiss1, a key activator of the reproductive function, is down-regulated in sexually inactive hamsters maintained in inhibitory short days (SDs). In rode......In seasonal breeders, reproduction is synchronized to seasons by day length via the pineal hormone melatonin. Recently, we have demonstrated that Kiss1, a key activator of the reproductive function, is down-regulated in sexually inactive hamsters maintained in inhibitory short days (SDs...... differentially regulate Kiss1 expression in the ARC and the AVPV. Kiss1 expression was examined by in situ hybridization in both male and female hamsters kept in various experimental conditions, and we observed that 1) SD exposure markedly reduced Kiss1 expression in the ARC and AVPV of male and female hamsters...... as compared to LD animals, 2) sex steroid treatment in SD-adapted male and female hamsters increased the number of Kiss1 neurons in the AVPV but decreased it in the ARC, 3) melatonin administration to LD-adapted hamsters decreased Kiss1 mRNA level in both the AVPV and the ARC in intact animals, whereas...

  9. Effect of Gonadectomy on the Androgen-Dependent Behavior of Ganglion Cell-Like Cells in Djungarian Hamsters (Phodopus sungorus).

    Science.gov (United States)

    Nakahira, Rei; Yoshida, Rumika; Michishita, Masaki; Ohkusu-Tsukada, Kozo; Takahashi, Kimimasa

    2016-02-01

    Ganglion cell-like (GL) cells reside in the dermis of the ventral skin of mature male Djungarian hamsters (Phodopus sugorus) and express androgen receptor (AR). To assess whether GL cells have androgen-dependent behavior, we evaluated the histologic changes of GL cells after gonadectomy. Five male and 5 female hamsters were gonadectomized at the age of 4 wk and necropsied 14 wk later. The number, distribution, and proliferative activity of GL cells in the thoracoabdominal and dorsal skins were evaluated histologically and compared with those of corresponding intact animals. GL cells were more numerous, were distributed throughout the skin more widely, and had higher proliferative activity in the intact male hamsters than in their gonadectomized counterparts. Similar trends regarding these 3 parameters were seen in ovariectomized compared with intact female hamsters and between intact male and intact female hamsters. These results suggest that the GL cells of Djungarian hamsters demonstrate sex-associated differences in their distribution and proliferative activity and that androgen may be involved in the development of these cells.

  10. The Middle East respiratory syndrome coronavirus (MERS-CoV does not replicate in Syrian hamsters.

    Directory of Open Access Journals (Sweden)

    Emmie de Wit

    Full Text Available In 2012 a novel coronavirus, MERS-CoV, associated with severe respiratory disease emerged in the Arabian Peninsula. To date, 55 human cases have been reported, including 31 fatal cases. Several of the cases were likely a result of human-to-human transmission. The emergence of this novel coronavirus prompts the need for a small animal model to study the pathogenesis of this virus and to test the efficacy of potential intervention strategies. In this study we explored the use of Syrian hamsters as a small animal disease model, using intratracheal inoculation and inoculation via aerosol. Clinical signs of disease, virus replication, histological lesions, cytokine upregulation nor seroconversion were observed in any of the inoculated animals, indicating that MERS-CoV does not replicate in Syrian hamsters.

  11. Chinese hamster ovary mutant UV-1 is hypomutable and defective in a postreplication recovery process

    International Nuclear Information System (INIS)

    Stamato, T.D.; Hinkle, L.; Collins, A.R.; Waldren, C.A.

    1981-01-01

    CHO-UV-1 is a mutant of the Chinese hamster cell CHO-K1 hypersensitive to killing by ultraviolet light but with normal resistance to X-ray. It is also hypersensitive to killing by ethyl methane sulfonate. Hybrid clones formed bu fusing UV-1 and Chinese hamster lung cells display the normal ultraviolet resistance of the latter. The sensitive phenotype behaves, therefore, in a genetically recessive manner. Ultraviolet sensitivity of UV-1 is not associated with a deficiency in excision repair. Alkaline sucrose gradient sedimentation analysis of nascent DNA from ultraviolet-irradiated cells reveals that UV-1 is, however, markedly deficient in postreplication recovery. Furthermore, UV-1 has a lower rate of induced mutation to 6-thioguanine resistance than does the parental cell when treated with ultraviolet light or ethyl methane sulfonate. These results suggest that the phenotype of UV-1 is due to a mutation in a form of postreplication recovery which in normal cells is error prone

  12. Blood epididymal barrier to [3H]-inulin in intact and vasectomized hamsters

    International Nuclear Information System (INIS)

    Turner, T.T.; D'Addario, D.A.; Howards, S.S.

    1981-01-01

    The net transport of [ 3 H]-inulin into the fluids of the hamster seminiferous and caput, corpus, and cauda epididymal tubules was examined in both intact animals and those vasectomized 10 months previously. Mean isotope concentrations in reproductive tract tubule fluids did not exceeded 10 per cent of blood plasma isotope concentrations during the experiment. There were no significant differences in net transport of [ 3 H]-inulin into any of the tubule fluids sampled. Ten months after vasectomy, the seminiferous tubule, and all regions of the epididymal tubule retain the capacity to exclude [ 3 H]-insulin. Thus in the hamster 10 months after vasectomy, the blood testis and blood epididymal barriers to inulin are intact

  13. Spontaneous mutation rate in Chinese hamster cell clones differing in UV-sensitivity

    International Nuclear Information System (INIS)

    Manuilova, E.S.; Bagrova, A.M.; Moskovskij Gosudarstvennyj Univ.

    1983-01-01

    The spontaneous rate of appearance of mutations to 6-mercaptopurine (6 MP) resistence in the cells of CHR2 and CHs2 clones dofferent in sensitivity to lethal and matagenous effect of UV-rays, is investigated. Increased UV-sensitivity of CHs2 clone is caused by the violation of postreplicative DNA reparation. It is established that the purity of spontaneously occuring mutations in both clones turns out to be similar, i.e. (1.5-1.8)x10 -5 for the cell pergeneration. It is shown that the effect of postreplicative DNA reparation in the cells of chinese hamster is not connected with the increase of spontaneous mutation ability. The problem on the possible role of reparation in the mechanism of appearance of spontaneous and induced mutations in the cells of Chinese hamster with increased UV-sensitivity is discussed

  14. Investigation of Blue Bedding in Cages Housing Treatment-Naïve Hamsters

    Science.gov (United States)

    Shah, Vishal D; Walton, Betsy J; Culp, Amanda G; Castellino, Stephen

    2015-01-01

    During the acclimation phase of a preclinical safety study involving Syrian golden hamsters, some of the cages of treatment-naïve animals were noted to contain blue-tinged bedding; the urine of these hamsters was not discolored. We sought to understand the underlying cause of this unusual finding to ensure that the study animals were healthy and free from factors that might confound the interpretation of the study. Analysis of extracts from the blue bedding by using HPLC with inline UV detection and high-resolution mass spectrometry indicated that the color was due to the presence of indigo blue. Furthermore, the indigo blue likely was formed through a series of biochemical events initiated by the intestinal metabolism of tryptophan to an indoxyl metabolite. We offer 2 hypotheses regarding the fate of the indoxyl metabolite: indigo blue formation through oxidative coupling in the liver or through urinary bacterial metabolism. PMID:26632791

  15. The effect of cigarette smoke on the metabolism of arachidonic acid in isolated hamster lungs

    International Nuclear Information System (INIS)

    Maennistoe, J.; Toivonen, H.; Hartiala, J.; Bakhle, Y.S.; Uotila, P.

    1981-01-01

    The effects of cigarette smoke on the metabolism of exogenous arachidonic acid (AA) were investigated in isolated hamster lungs. Arachidonate was injected into the pulmonary circulation and the metabolites were analysed from the nonrecirculating perfusion effluent by thin layer chromatography. After the pulmonary injection of 66 nmol of 14C-AA about 20% of the injected radioactivity appeared in the perfusion effluent mostly as metabolites in six minutes. When isolated lungs were ventilated with cigarette smoke during the perfusion, the amounts of PGF2 alpha, PGE2 and two unidentified metabolite groups increased in the lung effluent. In two other experimental series hamsters were exposed to cigarette smoke before the lung perfusion either once for 30 min or during one hour daily for ten consecutive days. Neither pre-exposures caused any changes in the amounts of arachidonate metabolites in the lung effluent

  16. MS-8209, a new amphotericin B derivative, provides enhanced efficacy in delaying hamster scrapie.

    Science.gov (United States)

    Adjou, K T; Demaimay, R; Lasmezas, C; Deslys, J P; Seman, M; Dormont, D

    1995-12-01

    To test the efficacy of a new amphotericin B derivative, MS-8209, in delaying scrapie, hamsters were infected intracerebrally with the 263K scrapie agent and treated with MS-8209 either early in the course of the disease or continuously. The results show that (i) all treatments lengthened the incubation period of hamster scrapie, (ii) continuous treatment with MS-8209 doubled the length of the incubation period compared with that observed in infected, untreated animals, and (iii) all treatments delayed the accumulation of a proteinase-resistant prion protein and glial fibrillary acidic protein in the brain. These findings suggest that MS-8209 is a powerful tool for investigating the pathogenesis of transmissible subacute spongiform encephalopathies.

  17. Plasma lipids of golden Syrian hamsters fed dietary rose hip, sunflower, olive and coconut oils.

    Science.gov (United States)

    González, I; Escobar, M; Olivera, P

    1997-06-01

    Plasma lipids of male golden Syrian hamsters fed diets supplemented with 15% (w/w) rose hip, sunflower, olive, or coconut oils during four weeks were assessed. The results confirm the saturated fat hyperlipidemic effect on golden Syrian hamsters fed with the olive oil and coconut oil, reaching the highest triglyceride levels. The monounsaturated (olive oil) or polyunsaturated (rose hip and sunflower oils) fatty acid-rich-vegetable oils have a similar action on the HDL-cholesterol. No statistically significant difference was observed for total cholesterol, HDL-cholesterol and triglyceride plasma levels in the rose hip and sunflower groups, showing that the polyunsaturation degree of both oils does not affect those results. Compared with the plasma levels obtained in the olive and coconut oil groups, rose hip and sunflower oils present a marked hypolipidemic effect, which could be due to specific action of the series n-6 linoleic acid.

  18. Comparison of myocardial thallium and β-methyl iodophenyl pentadecanoic acid (BMIPP) distribution in cardiomyopathy hamster

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Sago, Masayoshi

    1989-01-01

    The usefulness of fatty acid imaging in the detection of cardiomyopathy was evaluated by comparing thallium and BMIPP myocardial distribution in Bio 14.6 Syrian Hamster (25 week ages). Autoradiography was performed in 3 using 3.7 MBq (100 μCi) of 125 I-BMIPP and 37 MBq (1 mCi) of 201 TlCl. In vivo pin-hole imaging was performed in 3 using 37 MBq (1 mCi) of 123 I-BMIPP and 37 MBq (1 mCi) of 201 TlCl. In all cardiomyopathy hamsters, decreased uptake of BMIPP compared to that of thallium was demonstrated. These findings suggest dilated cardiomyopathy is associated with severe focal alternation in the substrate used for the performance of myocardial work. In conclusion, myocardial imaging using BMIPP may be useful for early detection of myocardial degeneration compared to thallium in patients with dilated cardiomyopathy. (author)

  19. A review of respiratory system anatomy, physiology, and disease in the mouse, rat, hamster, and gerbil.

    Science.gov (United States)

    Kling, Melissa A

    2011-05-01

    The purpose of this article is to provide for practitioners a comprehensive overview of respiratory diseases, both infectious and noninfectious, in the mouse, rat, hamster, and gerbil. The information presented will also be useful for veterinarians pursuing board certification. Anatomy and physiology are briefly addressed, as those two facets alone could encompass an entire article for these species. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. In vivo genetic toxicity studies in Chinese hamsters fed irradiated or unirradiated foodstuffs

    International Nuclear Information System (INIS)

    Altmann, H.

    1982-01-01

    Two in vivo genetic toxicity studies were performed in Chinese hamsters fed irradiated or unirradiated diets of chicken, fish or dates in order to detect possible mutagenic effects caused by irradiating these foodstuffs. The tests selected for study were: 1. Chromosomal analysis of bone narrow cells and 2. DNA metabolism in spleen cells. Chicken, fish and dates were irradiated with doses of 7, 2.5 and 1 kGy respectively. These investigations were subsequently extended to include the effects of irradiated dried onions, pulses and cocoa beans on DNA metabolism in Chinese hamster spleen cells only. Dried onions were irradiated with doses of 0.15, 9 and 15 kGy, pulses with 10 kGy and cocoa beans with 3.2 to 5 kGy. In addition, a fumigated cocoa bean group was included. No significant differences in chromosomal aberration rate were detected between groups fed irradiated or unirradiated diets. Dried dates, whether irradiated or not, showed some evidence of genetic toxicity in their effect on DNA metabolism in the spleen cells of Chinese hamsters. Both date diets caused more strand breaks DNA than are usual for Chinese hamster spleen cells, but DNA repair was not adversely affected. Chicken, both irradiated and unirradiated, was found to enhance replicative DNA synthesis but had no effect on the DNA repair process. Irradiated fish, however, caused enhanced DNA synthesis compared to unirradiated fish, but also had no adverse effect on DNA repair. Irradiated white beans also enhanced DNA synthesis compared to controls whereas unirradiated samples inhibited synthesis. (orig./MG)

  1. Comparison of the pathogenicity of Nipah virus isolates from Bangladesh and Malaysia in the Syrian hamster.

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    Blair L DeBuysscher

    Full Text Available Nipah virus is a zoonotic pathogen that causes severe disease in humans. The mechanisms of pathogenesis are not well described. The first Nipah virus outbreak occurred in Malaysia, where human disease had a strong neurological component. Subsequent outbreaks have occurred in Bangladesh and India and transmission and disease processes in these outbreaks appear to be different from those of the Malaysian outbreak. Until this point, virtually all Nipah virus studies in vitro and in vivo, including vaccine and pathogenesis studies, have utilized a virus isolate from the original Malaysian outbreak (NiV-M. To investigate potential differences between NiV-M and a Nipah virus isolate from Bangladesh (NiV-B, we compared NiV-M and NiV-B infection in vitro and in vivo. In hamster kidney cells, NiV-M-infection resulted in extensive syncytia formation and cytopathic effects, whereas NiV-B-infection resulted in little to no morphological changes. In vivo, NiV-M-infected Syrian hamsters had accelerated virus replication, pathology and death when compared to NiV-B-infected animals. NiV-M infection also resulted in the activation of host immune response genes at an earlier time point. Pathogenicity was not only a result of direct effects of virus replication, but likely also had an immunopathogenic component. The differences observed between NiV-M and NiV-B pathogeneis in hamsters may relate to differences observed in human cases. Characterization of the hamster model for NiV-B infection allows for further research of the strain of Nipah virus responsible for the more recent outbreaks in humans. This model can be used to study NiV-B pathogenesis, transmission, and countermeasures that could be used to control outbreaks.

  2. Induction of polyspermy in sea urchin eggs by antibodies raised against a hamster sperm protein.

    Science.gov (United States)

    Sullivan, R; Coutu, L; Dubé, F

    1994-07-15

    Polyclonal antibodies raised against a hamster sperm protein (P26h) induce polyspermic fertilizations in the green sea urchin without affecting the fertilizing ability of the spermatozoa nor the elevation of the fertilization membrane. While the adsorption of the antibodies on sperm decreased the polyspermic effect, preincubation of unfertilized eggs with the anti-P26h did not cause polyspermy. These results suggest that common epitopes are involved in fertilization processes in phylogenetically distant species.

  3. In vivo metabolic activity of hamster suprachiasmatic nuclei: use of anesthesia

    International Nuclear Information System (INIS)

    Schwartz, W.J.

    1987-01-01

    In vivo glucose utilization was measured in the suprachiasmatic nuclei (SCN) of Golden hamsters using the 14 C-labeled deoxyglucose technique. A circadian rhythm of SCN metabolic activity could be measured in this species, but only during pentobarbital sodium anesthesia when the surrounding background activity of adjacent hypothalamus was suppressed. Both the SCN's metabolic oscillation and its time-keeping ability are resistant to general anesthesia

  4. Protective effect of dexamethasone on 5-FU-induced oral mucositis in hamsters.

    Science.gov (United States)

    Ribeiro, Susana Barbosa; de Araújo, Aurigena Antunes; Araújo Júnior, Raimundo Fernandes de; Brito, Gerly Anne de Castro; Leitão, Renata Carvalho; Barbosa, Maisie Mitchele; Garcia, Vinicius Barreto; Medeiros, Aldo Cunha; Medeiros, Caroline Addison Carvalho Xavier de

    2017-01-01

    Oral mucositis (OM) is an important side effect of cancer treatment, characterized by ulcerative lesions in the mucosa of patients undergoing radiotherapy or chemotherapy, which has marked effects on patient quality of life and cancer therapy continuity. Considering that few protocols have demonstrated efficacy in preventing this side effect, the aim of this study was to examine the effect of dexamethasone (DEX) on OM induced by 5-fluorouracil (5-FU) in hamsters by studying signaling pathways. OM was induced in hamsters by 5-FU followed by mechanical trauma (MT) on day 4. On day 10, the animals were euthanized. The experimental groups included saline, MT, 5-FU, and DEX (0.25, 0.5, or 1 mg/kg). Macroscopic, histopathological, and immunohistochemical analyses as well as immunofluorescence experiments were performed on the oral mucosa of the animals. The oral mucosal samples were analyzed by enzyme-linked immunosorbent assays, and quantitative real-time polymerase chain reaction (qPCR). DEX (0.5 or 1 mg/kg) reduced inflammation and ulceration of the oral mucosa of hamsters. In addition, DEX (1 mg/kg) reduced the cytokine levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and macrophage migration inhibitory factor (MIF). DEX (1 mg/kg) also reduced the immunoexpression of cyclooxygenase (COX)-2, matrix metalloproteinase (MMP)-2, transforming growth factor (TGF)-β, MIF, Smad 2/3, Smad 2/3 phosphorylated and NFκB p65 in the jugal mucosa. Finally, DEX (1 mg/kg) increased interleukin-1 receptor-associated kinase 3 (IRAK-M), glucocorticoid-induced leucine zipper (GILZ), and mitogen-activated protein kinase (MKP1) gene expression and reduced NFκB p65 and serine threonine kinase (AKt) gene expression, relative to the 5-FU group. Thus, DEX improved OM induced by 5-FU in hamsters.

  5. Protective effect of dexamethasone on 5-FU-induced oral mucositis in hamsters.

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    Susana Barbosa Ribeiro

    Full Text Available Oral mucositis (OM is an important side effect of cancer treatment, characterized by ulcerative lesions in the mucosa of patients undergoing radiotherapy or chemotherapy, which has marked effects on patient quality of life and cancer therapy continuity. Considering that few protocols have demonstrated efficacy in preventing this side effect, the aim of this study was to examine the effect of dexamethasone (DEX on OM induced by 5-fluorouracil (5-FU in hamsters by studying signaling pathways. OM was induced in hamsters by 5-FU followed by mechanical trauma (MT on day 4. On day 10, the animals were euthanized. The experimental groups included saline, MT, 5-FU, and DEX (0.25, 0.5, or 1 mg/kg. Macroscopic, histopathological, and immunohistochemical analyses as well as immunofluorescence experiments were performed on the oral mucosa of the animals. The oral mucosal samples were analyzed by enzyme-linked immunosorbent assays, and quantitative real-time polymerase chain reaction (qPCR. DEX (0.5 or 1 mg/kg reduced inflammation and ulceration of the oral mucosa of hamsters. In addition, DEX (1 mg/kg reduced the cytokine levels of tumor necrosis factor (TNF-α, interleukin (IL-1β, and macrophage migration inhibitory factor (MIF. DEX (1 mg/kg also reduced the immunoexpression of cyclooxygenase (COX-2, matrix metalloproteinase (MMP-2, transforming growth factor (TGF-β, MIF, Smad 2/3, Smad 2/3 phosphorylated and NFκB p65 in the jugal mucosa. Finally, DEX (1 mg/kg increased interleukin-1 receptor-associated kinase 3 (IRAK-M, glucocorticoid-induced leucine zipper (GILZ, and mitogen-activated protein kinase (MKP1 gene expression and reduced NFκB p65 and serine threonine kinase (AKt gene expression, relative to the 5-FU group. Thus, DEX improved OM induced by 5-FU in hamsters.

  6. Chemical constituents from Solidago canadensis with hypolipidemic effects in HFD-fed hamsters.

    Science.gov (United States)

    Huang, Ying; Hao, Yan-Li; Mai, Xiao-Yan

    2013-01-01

    Two new compounds, 8-dehydroxymethylvisanol (1) and 9-O-[3-O-acetyl-β-d-glucopyranosyl]-4-hydroxy-cinnamic acid (4), together with two known lignans, visanol (2) and 9-aldehydevibsanol (3), were isolated from the 80% EtOH extract of Solidago canadensis. The structures of the two new compounds were elucidated on the basis of 1D, 2D NMR, and mass spectral analysis. All the lignans exhibited moderate hypolipidemic activity in high-fat diet-fed hamsters.

  7. Somatic mutations in stilbene estrogen-induced Syrian hamster kidney tumors identified by DNA fingerprinting

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    Roy Deodutta

    2004-01-01

    Full Text Available Abstract Kidney tumors from stilbene estrogen (diethylstilbestrol-treated Syrian hamsters were screened for somatic genetic alterations by Random Amplified Polymorphic DNA-polymerase chain-reaction (RAPD-PCR fingerprinting. Fingerprints from tumor tissue were generated by single arbitrary primers and compared with fingerprints for normal tissue from the same animal, as well as normal and tumor tissues from different animals. Sixty one of the arbitrary primers amplified 365 loci that contain approximately 476 kbp of the hamster genome. Among these amplified DNA fragments, 44 loci exhibited either qualitative or quantitative differences between the tumor tissues and normal kidney tissues. RAPD-PCR loci showing decreased and increased intensities in tumor tissue DNA relative to control DNA indicate that loci have undergone allelic losses and gains, respectively, in the stilbene estrogen-induced tumor cell genome. The presence or absence of the amplified DNA fragments indicate homozygous insertions or deletions in the kidney tumor DNA compared to the age-matched normal kidney tissue DNA. Seven of 44 mutated loci also were present in the kidney tissues adjacent to tumors (free of macroscopic tumors. The presence of mutated loci in uninvolved (non-tumor surrounding tissue adjacent to tumors from stilbene estrogen-treated hamsters suggests that these mutations occurred in the early stages of carcinogenesis. The cloning and sequencing of RAPD amplified loci revealed that one mutated locus had significant sequence similarity with the hamster Cyp1A1 gene. The results show the ability of RAPD-PCR to detect and isolate, in a single step, DNA sequences representing genetic alterations in stilbene estrogen-induced cancer cells, including losses of heterozygosity, and homozygous deletion and insertion mutations. RAPD-PCR provides an alternative molecular approach for studying cancer cytogenetics in stilbene estrogen-induced tumors in humans and experimental

  8. Response of preadult Necator americanus to some known anthelmintics in hamsters.

    Science.gov (United States)

    Rajasekariah, G R; Deb, B N; Dhage, K R; Bose, S

    1986-01-01

    Hamsters infected with laboratory-adapted preadult Necator americanus were dosed with 6 reference anthelmintics. Their efficacy was measured in terms of percentage cure of infected animals as well as percentage worm reduction following treatment. Mebendazole and pyrantel were equally effective in this system. Other anthelmintics, including anti-hookworm compound, bephenium hydroxynaphthoate, were less effective. The comparative results revealed that the N. americanus model is sensitive and reliable for identifying and characterizing new anti-parasite preparations.

  9. The effect of hydroxyurea on synchronized Chinese hamster ovary cells irradiated by ultraviolet light

    International Nuclear Information System (INIS)

    Burg, K.; Collins, A.R.S.; Johnson, R.T.

    1979-01-01

    The effect of hydroxyurea (HU) on cell survival was investigated in Chinese hamster ovary cells after different radiation doses of UV light (254 nm) during the individual phases of the cell cycle. HU inhibits the repair DNA replication by mediation through the DNA precursor pool. These results are supported by the absence of the effect of HU both in the G2 phase possessing high levels of precursors and in supplying the 4 deoxyribonucleosides together with HU after irradiation

  10. Pharmacological studies of a new derivative of amphotericin B, MS-8209, in mouse and hamster scrapie.

    Science.gov (United States)

    Demaimay, R; Adjou, K; Lasmézas, C; Lazarini, F; Cherifi, K; Seman, M; Deslys, J P; Dormont, D

    1994-09-01

    Transmissible subacute spongiform encephalopathies (TSSE) are neurodegenerative diseases characterized by the presence of a modified, partially proteinase-resistant host protein, PrPSc, which accumulates in the brains of infected individuals. Recently it has been reported that amphotericin B (AmB) treatment of hamsters infected with scrapie strain 263K prolongs the incubation period of the disease, and dissociates in vivo replication of the scrapie agent from PrPSc accumulation. We report here on data obtained after treatment with AmB and one of its derivatives, MS-8209, in experimental scrapie of mouse and hamster. Treatment was carried out by the intraperitoneal route 6 days per week, at three different dosages initiated at the time of infection. Two regimens were used: during the early time of infection or throughout the experimental infection. Results indicate that MS-8209 was as efficient as AmB in prolonging the incubation time and decreasing PrPSc accumulation in the hamster scrapie model. A dose-dependent response was observed in mice treated early after experimental infection. At a dose of 2.5 mg/kg, MS-8209 significantly prolonged the incubation period (by 11.9%). In long-term treatment of mice, MS-8209 and AmB markedly reduced PrPSc levels in the preclinical stage of the disease. These data demonstrate that the effect of AmB is not restricted to one model (hamster-263K). This regimen leads to an inversion of the PrPSc to proteinase-sensitive protein (PrPSens) ratio, suggesting PrPSens (presumably cellular PrPC) accumulation occurs before its conversion into PrPSc. As it has been shown that AmB does not modify the infectivity titre, we conclude that the drugs could act by inhibiting either the interaction of the scrapie agent with PrPSens during the early times of infection or the conversion of PrPSens into PrPSc.

  11. Role of chymase in cigarette smoke-induced pulmonary artery remodeling and pulmonary hypertension in hamsters

    OpenAIRE

    Yang Ting; Xu Dan; An Jin; He Guang-Ming; Chen Ya-Juan; Chen Lei; Ning Yun-Ye; Zhang Shang-Fu; Han Su-Xia; Wang Tao; Zhang Xiao-Hong; Wen Fu-Qiang

    2010-01-01

    Abstract Background Cigarette smoking is an important risk factor for pulmonary arterial hypertension (PAH) in chronic obstructive pulmonary disease (COPD). Chymase has been shown to function in the enzymatic production of angiotensin II (AngII) and the activation of transforming growth factor (TGF)-β1 in the cardiovascular system. The aim of this study was to determine the potential role of chymase in cigarette smoke-induced pulmonary artery remodeling and PAH. Methods Hamsters were exposed ...

  12. Role of chymase in cigarette smoke-induced pulmonary artery remodeling and pulmonary hypertension in hamsters

    Directory of Open Access Journals (Sweden)

    Yang Ting

    2010-03-01

    Full Text Available Abstract Background Cigarette smoking is an important risk factor for pulmonary arterial hypertension (PAH in chronic obstructive pulmonary disease (COPD. Chymase has been shown to function in the enzymatic production of angiotensin II (AngII and the activation of transforming growth factor (TGF-β1 in the cardiovascular system. The aim of this study was to determine the potential role of chymase in cigarette smoke-induced pulmonary artery remodeling and PAH. Methods Hamsters were exposed to cigarette smoke; after 4 months, lung morphology and tissue biochemical changes were examined using immunohistochemistry, Western blotting, radioimmunoassay and reverse-transcription polymerase chain reaction. Results Our results show that chronic cigarette smoke exposure significantly induced elevation of right ventricular systolic pressures (RVSP and medial hypertrophy of pulmonary arterioles in hamsters, concurrent with an increase of chymase activity and synthesis in the lung. Elevated Ang II levels and enhanced TGF-β1/Smad signaling activation were also observed in smoke-exposed lungs. Chymase inhibition with chymostatin reduced the cigarette smoke-induced increase in chymase activity and Ang II concentration in the lung, and attenuated the RVSP elevation and the remodeling of pulmonary arterioles. Chymostatin did not affect angiotensin converting enzyme (ACE activity in hamster lungs. Conclusions These results suggest that chronic cigarette smoke exposure can increase chymase activity and expression in hamster lungs. The capability of activated chymase to induce Ang II formation and TGF-β1 signaling may be part of the mechanism for smoking-induced pulmonary vascular remodeling. Thus, our study implies that blockade of chymase might provide benefits to PAH smokers.

  13. Omega 3 fatty acids promote macrophage reverse cholesterol transport in hamster fed high fat diet.

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    Fatima Kasbi Chadli

    Full Text Available The aim of this study was to investigate macrophage reverse cholesterol transport (RCT in hamster, a CETP-expressing species, fed omega 3 fatty acids (ω3PUFA supplemented high fat diet (HFD. Three groups of hamsters (n = 6/group were studied for 20 weeks: 1 control diet: Control, 2 HFD group: HF and 3 HFD group supplemented with ω3PUFA (EPA and DHA: HFω3. In vivo macrophage-to-feces RCT was assessed after an intraperitoneal injection of (3H-cholesterol-labelled hamster primary macrophages. Compared to Control, HF presented significant (p<0.05 increase in body weight, plasma TG (p<0.01 and cholesterol (p<0.001 with an increase in VLDL TG and in VLDL and LDL cholesterol (p<0.001. Compared to HF, HFω3 presented significant decrease in body weight. HFω3 showed less plasma TG (p<0.001 and cholesterol (p<0.001 related to a decrease in VLDL TG and HDL cholesterol respectively and higher LCAT activity (p<0.05 compared to HF. HFω3 showed a higher fecal bile acid excretion (p<0.05 compared to Control and HF groups and higher fecal cholesterol excretion (p<0.05 compared to HF. This increase was related to higher gene expression of ABCG5, ABCA1 and SR-B1 in HFω3 compared to Control and HF groups (<0.05 and in ABCG1 and CYP7A1 compared to HF group (p<0.05. A higher plasma efflux capacity was also measured in HFω3 using (3H- cholesterol labeled Fu5AH cells. In conclusion, EPA and DHA supplementation improved macrophage to feces reverse cholesterol transport in hamster fed HFD. This change was related to the higher cholesterol and fecal bile acids excretion and to the activation of major genes involved in RCT.

  14. Autoradiographic studies of the kidneys of hamsters bearing longterm oestrogen implants

    International Nuclear Information System (INIS)

    Pantic, V.; Li, J.; Villee, C.

    1974-01-01

    The ability of kidney cells to incorporate tritiated oestradiol, thymidine or uridine was investigated in hamsters with oestrogen implants for more than six months and in corresponding control hamsters without implants. Using autoradiography the following results were obtained: The cells of some proportion of the proximal convoluted tubules showed an increased ability to incorporate tritiated oestradiol, thymidine and uridine. Many of these cells were able to transport the labeled oestrogen-receptor complex into the nuclei within 45 minutes after the administration of labeled oestradiol. The cells of the distal convoluted tubules were labeled but generally to a much smaller extent. Only some individual cells showed a tendency for an increased accumulation of oestradiol. The cytoplasm of cells in the loop of Henle seems to be covered uniformly with silver grains in both control and oestrogen treated hamsters. The cells of collecting and papillary duct tubules located in the medullary rays do not show any tendency for an increased uptake of labeled oestradiol. (orig.) [de

  15. Comparison of hesperetin and its metabolites for cholesterol-lowering and antioxidative efficacy in hypercholesterolemic hamsters.

    Science.gov (United States)

    Kim, Hye-Jin; Jeon, Seon-Min; Lee, Mi-Kyung; Cho, Yun-Young; Kwon, Eun-Young; Lee, Jin Hee; Choi, Myung-Sook

    2010-08-01

    This study was performed to compare the hypolipidemic and antioxidant efficacy of hesperetin and its metabolites in hypercholesterolemic hamsters. The hamsters were fed a high-fat (10% coconut oil and 0.2% cholesterol, wt/wt) diet or a high-fat diet supplemented with hesperetin (0.02%) or hesperetin metabolites, 3,4-dihydroxyphenylpropionic acid (DHPP) (0.012%) and 3-methoxy-4-hydroxycinnamic acid (ferulic acid) (0.013%), for 12 weeks. Dietary DHPP and ferulic acid were found to have significantly decreased the levels of the plasma total cholesterol, non-high-density lipoprotein-cholesterol (HDL-C), apolipoprotein B, hepatic lipids, and cholesterol-regulating enzymes compared to the control group. In particular, ferulic acid was more potent with respect to raising HDL-C/total cholesterol ratio and paraoxonase levels while decreasing atherogenic index values. Hesperetin and its metabolites seemed to enhance antioxidant capacity by lowering the hydrogen peroxide and lipid peroxide (thiobarbituric acid-reactive substrates) levels. Among the hesperetin metabolites tested, the relative potency of ferulic acid for reducing the risks of atherosclerosis in hamsters was found to be greater.

  16. Photodynamic vaccination of hamsters with inducible suicidal mutants of Leishmania amazonensis elicits immunity against visceral leishmaniasis

    Science.gov (United States)

    Kumari, Shraddha; Samant, Mukesh; Khare, Prashant; Misra, Pragya; Dutta, Sujoy; Kolli, Bala Krishna; Sharma, Sharad; Chang, Kwang Poo; Dube, Anuradha

    2016-01-01

    Leishmania, naturally residing in the phagolysosomes of macrophages, is a suitable carrier for vaccine delivery. Genetic complementation of these trypanosomatid protozoa to partially rectify their defective heme-biosynthesis renders them inducible with δ-aminolevulinate to develop porphyria for selective photolysis, leaving infected host-cells unscathed. Delivery of released “vaccines” to antigen-presenting cells is thus expected to enhance immune response, while their self-destruction presents added advantages of safety. Such suicidal-L. amazonensis was found to confer immunoprophylaxis and immunotherapy on hamsters against L. donovani. Neither heat-killed nor live parasites without suicidal induction were effective. Photodynamic vaccination of hamsters with the suicidal-mutants reduced the parasite loads by 99% and suppressed the development of disease. These suppressions were accompanied by an increase in Leishmania-specific delayed-type hypersensitivity and lymphoproliferation as well as in the levels of splenic iNOS, IFN-γ and IL-12 expressions and of Leishmania-specific IgG2 in the serum. Moreover, a single intravenous administration of T-cells from vaccinated hamsters was shown to confer on naïve animals an effective cellular immunity against L. donovani challenges. The absence of lesion development at vaccination sites and parasites in the draining lymphnodes, spleen and liver further indicates that the suicidal mutants provide a safe platform for vaccine delivery against experimental visceral leishmaniasis. PMID:19053149

  17. Energy budget, behavior and leptin in striped hamsters subjected to food restriction and refeeding.

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    Zhi-Jun Zhao

    Full Text Available Food restriction induces a loss of body mass that is often followed by rapid regaining of the lost weight when the restriction ends, consequently increasing a risk of development of obesity. To determine the physiological and behavioral mechanisms underlining the regaining, striped hamsters were restricted to 85% of initial food intake for 4 weeks and refed ad libitum for another 4 weeks. Changes in body mass, energy budget, activity, body composition and serum leptin level were measured. Body mass, body fat mass and serum leptin level significantly decreased in food-restricted hamsters, and increased when the restriction ended, showing a short "compensatory growth" rather than over-weight or obesity compared with ad libitum controls. During restriction, the time spent on activity increased significantly, which was opposite to the changes in serum leptin level. Food intake increased shortly during refeeding, which perhaps contributed to the rapid regaining of body mass. No correlation was observed between serum leptin and energy intake, while negative correlations were found in hamsters that were refed for 7 and 28 days. Exogenous leptin significantly decreased the time spent on activity during food restriction and attenuated the increase in food intake during refeeding. This suggests that low leptin in restricted animals may function as a starvation signal to induce an increase in activity behavior, and high leptin likely serves as a satiety signal to prevent activity during refeeding. Leptin may play a crucial role in controlling food intake when the restriction ends, and consequently preventing overweight.

  18. Intranasal immunization with LACK-DNA promotes protective immunity in hamsters challenged with Leishmania chagasi.

    Science.gov (United States)

    DE Oliveira Gomes, Daniel Claudio; DA Silva Costa Souza, Beatriz Lilian; DE Matos Guedes, Herbert Leonel; Lopes, Ulisses Gazos; Rossi-Bergmann, Bartira

    2011-12-01

    LACK (Leishmania analogue of the receptor kinase C) is a conserved protein in protozoans of the genus Leishmania which is associated with the immunopathogenesis and susceptibility of BALB/c mice to L. major infection. Previously, we demonstrated that intranasal immunization with a plasmid carrying the LACK gene of Leishmania infantum (LACK-DNA) promotes protective immunity in BALB/c mice against Leishmania amazonensis and Leishmania chagasi. In the present study, we investigated the protective immunity achieved in hamsters intranasally vaccinated with 2 doses of LACK-DNA (30 μg). Compared with controls (PBS and pCI-neo plasmid), animals vaccinated with LACK-DNA showed significant reduction in parasite loads in the spleen and liver, increased lymphoproliferative response and increased nitric oxide (NO) production by parasite antigen-stimulated splenocytes. Furthermore, hamsters vaccinated with LACK-DNA presented high IgG and IgG2a serum levels when compared to control animals. Our results showed that intranasal vaccination with LACK-DNA promotes protective immune responses in hamsters and demonstrated the broad spectrum of intranasal LACK-DNA efficacy in different host species, confirming previous results in murine cutaneous and visceral leishmaniasis.

  19. Body temperature in the mouse, hamster, and rat exposed to radiofrequency radiation: an interspecies comparison

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, C.J.; Long, M.D.; Fehlner, K.S.; Stead, A.G.

    1986-01-01

    Colonic temperatures of BALB/c and CBA/J mice, golden hamsters, and Sprague-Dawley rats were taken immediately after exposure for 90 min to radiofrequency (RF) radiation. Exposures were made in 2450 MHz (mouse and hamster) or 600-MHz (rat) waveguide exposure systems while the dose rate, to specific adsorption rate (SAR), was continuously recorded. Experiments were performed on naive, unrestrained animals at ambient temperatures (Ta) of 20 and 30 C. Body mass and Ta were found to be significant factors in influencing the threshold SAR for the elevation of colonic temperature. The threshold SARs at Ta's of 20 and 30 C were, respectively: 27.5 and 12.1 W/kg for the BALB/c mouse; 40.7 and 8.5 W/kg for the CBA/J mouse; 8.7 and 0.61 W/kg for the golden hamster; and 1.58 and 0.4 W/kg for the Sprague-Dawley rat.

  20. Effects of exogenous leptin on seasonal reproductive responses to interacting environmental cues in female Siberian hamsters.

    Science.gov (United States)

    Bailey, Allison M; Legan, Sandra J; Meretsky, Vicky J; Demas, Gregory E

    2017-09-01

    Animals living in temperate climates respond to environmental cues that signal current and future resource availability to ensure that energy resources are available to support reproduction. Siberian hamsters (Phodopus sungorus) undergo robust gonadal regression in short, winter-like photoperiods as well as in response to mild food restriction in intermediate photoperiods. The goal of the present study was to investigate whether leptin is a relevant metabolic signal in regulating gonadal regression in response to diminishing food availability. Adult female hamsters housed in short-day (winter-like) or intermediate (fall-like) photoperiods received either ad libitum access to food or mild food restriction (90% of ad libitum intake) and were treated with either leptin or a vehicle for five weeks in order to determine the ability of leptin to inhibit gonadal regression. At the end of five weeks, vehicle-treated hamsters showed physiological signs associated with ongoing gonadal regression, such as decreases in body mass and food intake, cessation of estrous cycling, and small decreases in reproductive tissue mass. Leptin did not modify changes in body mass, food intake, hormone concentration, or tissue mass, but showed a tendency to support estrous cycling, particularly in response to food restriction in the intermediate photoperiod treatment. Overall, leptin appears to play a minor role in coordinating reproductive responses to multiple environmental cues, at least in the early stages of gonadal regression. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. The gastrointestinal absorption of organically bound forms of plutonium in fed and fasted hamsters

    International Nuclear Information System (INIS)

    Harrison, J.D.; Cooper, J.R.; Bomford, J.A.; David, A.J.

    1986-01-01

    Values of about 0.005-0.01% were obtained for the absorption in fed hamsters of plutonium ingested as Pu 4+ citrate, isocitrate, phytate and malate complexes and Pu 3+ ascorbate compared with about 0.003-0.004% for Pu 4+ nitrate. Replacing drinking water with tea did not affect the result for Pu 4+ nitrate. Fasting hamsters for 8 h before the administration of plutonium citrate increased absorption to 0.1-0.2%. An extra period of fasting for 4 h after administration did not lead to a further increase in absorption. Similar values were also obtained when plutonium citrate was administered after a 24 h fast, followed either by immediate access to food or a further 4 h fast. In hamsters fasted for 24 h before administration of either Pu 3+ ascorbate or Pu 4+ nitrate, about 6-7 per cent of the ingested plutonium was retained in the gastrointestinal tract after one week. At three weeks after ingestion of Pu 3+ ascorbate, gastrointestinal retention had fallen 100-fold without an increase in absorption. (author)

  2. Immunization with recombinant enterovirus 71 viral capsid protein 1 fragment stimulated antibody responses in hamsters

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    Ch’ng Wei-Choong

    2012-08-01

    Full Text Available Abstract Enterovirus 71 (EV71 causes severe neurological diseases resulting in high mortality in young children worldwide. Development of an effective vaccine against EV71 infection is hampered by the lack of appropriate animal models for efficacy testing of candidate vaccines. Previously, we have successfully tested the immunogenicity and protectiveness of a candidate EV71 vaccine, containing recombinant Newcastle disease virus capsids that display an EV71 VP1 fragment (NPt-VP11-100 protein, in a mouse model of EV71 infection. A drawback of this system is its limited window of EV71 susceptibility period, 2 weeks after birth, leading to restricted options in the evaluation of optimal dosing regimens. To address this issue, we have assessed the NPt-VP11-100 candidate vaccine in a hamster system, which offers a 4-week susceptibility period to EV71 infection. Results obtained showed that the NPt-VP11-100 candidate vaccine stimulated excellent humoral immune response in the hamsters. Despite the high level of antibody production, they failed to neutralize EV71 viruses or protect vaccinated hamsters in viral challenge studies. Nevertheless, these findings have contributed towards a better understanding of the NPt-VP11-100 recombinant protein as a candidate vaccine in an alternative animal model system.

  3. Development of novel DNA markers for genetic analysis of grey hamsters by cross-species amplification of microsatellites.

    Science.gov (United States)

    Wang, C; Zhang, S J; Du, X Y; Xu, Y M; Huo, X Y; Liao, L F; Chen, Z W

    2015-11-13

    The grey hamster has been used in biomedical research for decades. However, effective molecular methods for evaluating the genetic structure of this species are lacking, which hinders its wider usage. In this study, we employed cross-amplification of microsatellite loci of species within the same genus by polymerase chain reaction. Loci screened included 107 from the Mongolian gerbil (MG) and 60 from the Chinese hamster (CH); of these, 15 polymorphic loci were identified for the grey hamster. Of the 167 loci screened, 95 (56.9%) with clear bands on agarose gel were initially identified. After sequencing, 74 (77.9%) of these matched the criteria for microsatellite characteristics, including 41 from MG and 33 from CH. Lastly, 15 (20.3%) loci with more than two alleles for each locus were identified through capillary electrophoresis scanning. To justify the applicability of the 15 grey hamster loci, genetic indexes of grey hamsters were evaluated using 46 generations of outbred stock, established 20 years ago, from Xinjiang, China. Mean effective allele numbers and expected heterozygosity of stock were as low as, respectively, 1.2 and 0.14; these were 2.8 and 4.0 times inferior, respectively, to wild grey hamsters. This finding suggests that the genetic structure of the stock-bred population is too weak to resist artificial and natural selection, mutation and genetic drifting. In conclusion, we have developed de novo microsatellite markers for genetic analysis of the grey hamster, providing data and methodology for the enrichment of a genetic library for this species.

  4. Acute toxicity of high doses of the glycoalkaloids, alpha-solanine and alpha-chaconine, in the Syrian Golden hamster

    DEFF Research Database (Denmark)

    Langkilde, Søren; Schrøder, Malene; Stewart, Derek

    2008-01-01

    Golden hamsters. Daily doses of 100 mg of alpha-solanine [kg body weight (BW)](-1) induced death in two of four hamsters within 4 days, when administered by gavage to female Syrian hamsters. Doses of 100 mg of alpha-chaconine alone or alpha-solanine and alpha-chaconine combined in a ratio of 1......:2.5, in doses of 75 or 100 mg (kg BW)(-1), induced death in one of four hamsters within the same period. Animals dosed with alpha-solanine alone or in combination with alpha-chaconine suffered from fluid-filled and dilated small intestines. The GA administration had no effect on acetyl cholinesterase (ACh......), beta(2), and gamma-GAs detected in the urine and, to a lesser extent, the feces. Doses from 75 mg (kg BW)(-1) of alpha-chaconine, alpha-solanine, or the two compounds combined were potentially lethal within 4-5 days in the Syrian Golden hamster. However, the cause of death in these studies could...

  5. Red algae (Gelidium amansii) hot-water extract ameliorates lipid metabolism in hamsters fed a high-fat diet.

    Science.gov (United States)

    Yang, Tsung-Han; Yao, Hsien-Tsung; Chiang, Meng-Tsan

    2017-10-01

    The purpose of this study was to investigate the effects of Gelidium amansii (GA) hot-water extracts (GHE) on lipid metabolism in hamsters. Six-week-old male Syrian hamsters were used as the experimental animals. Hamsters were divided into four groups: (1) control diet group (CON); (2) high-fat diet group (HF); (3) HF with GHE diet group (HF + GHE); (4) HF with probucol diet group (HF + PO). All groups were fed the experimental diets and drinking water ad libitum for 6 weeks. The results showed that GHE significantly decreased body weight, liver weight, and adipose tissue (perirenal and paraepididymal) weight. The HF diet induced an increase in plasma triacylglycerol (TG), total cholesterol (TC), low-density lipoprotein cholesterol and very-low-density lipoprotein cholesterol levels. However, GHE supplementation reversed the increase of plasma lipids caused by the HF diet. In addition, GHE increased fecal cholesterol, TG and bile acid excretion. Lower hepatic TC and TG levels were found with GHE treatment. GHE reduced hepatic sterol regulatory element-binding proteins (SREBP) including SREBP 1 and SREBP 2 protein expressions. The phosphorylation of adenosine monophosphate (AMP)-activated protein kinase (AMPK) protein expression in hamsters was decreased by the HF diet; however, GHE supplementation increased the phosphorylation of AMPK protein expression. Our results suggest that GHE may ameliorate lipid metabolism in hamsters fed a HF diet. Copyright © 2017. Published by Elsevier B.V.

  6. neu mutation in schwannomas induced transplacentally in Syrian golden hamsters by N-nitrosoethylurea: high incidence but low allelic representation.

    Science.gov (United States)

    Buzard, G S; Enomoto, T; Hongyo, T; Perantoni, A O; Diwan, B A; Devor, D E; Reed, C D; Dove, L F; Rice, J M

    1999-10-01

    Peripheral nerve tumors (PNT) and melanomas induced transplacentally on day 14 of gestation in Syrian golden hamsters by N-nitrosoethylurea were analyzed for activated oncogenes by the NIH 3T3 transfection assay, and for mutations in the neu oncogene by direct sequencing, allele-specific oligonucleotide hybridization, MnlI restriction-fragment-length polymorphism, single-strand conformation polymorphism, and mismatch amplification mutation assays. All (67/67) of the PNT, but none of the melanomas, contained a somatic missense T --> A transversion within the neu oncogene transmembrane domain at a site corresponding to that which also occurs in rat schwannomas transplacentally induced by N-nitrosoethylurea. In only 2 of the 67 individual hamster PNT did the majority of tumor cells appear to carry the mutant neu allele, in contrast to comparable rat schwannomas in which it overwhelmingly predominates. The low fraction of hamster tumor cells carrying the mutation was stable through multiple transplantation passages. In the hamster, as in the rat, specific point-mutational activation of the neu oncogene thus constitutes the major pathway for induction of PNT by transplacental exposure to an alkylating agent, but the low allelic representation of mutant neu in hamster PNT suggests a significant difference in mechanism by which the mutant oncogene acts in this species.

  7. Red algae (Gelidium amansii hot-water extract ameliorates lipid metabolism in hamsters fed a high-fat diet

    Directory of Open Access Journals (Sweden)

    Tsung-Han Yang

    2017-10-01

    Full Text Available The purpose of this study was to investigate the effects of Gelidium amansii (GA hot-water extracts (GHE on lipid metabolism in hamsters. Six-week-old male Syrian hamsters were used as the experimental animals. Hamsters were divided into four groups: (1 control diet group (CON; (2 high-fat diet group (HF; (3 HF with GHE diet group (HF + GHE; (4 HF with probucol diet group (HF + PO. All groups were fed the experimental diets and drinking water ad libitum for 6 weeks. The results showed that GHE significantly decreased body weight, liver weight, and adipose tissue (perirenal and paraepididymal weight. The HF diet induced an increase in plasma triacylglycerol (TG, total cholesterol (TC, low-density lipoprotein cholesterol and very-low-density lipoprotein cholesterol levels. However, GHE supplementation reversed the increase of plasma lipids caused by the HF diet. In addition, GHE increased fecal cholesterol, TG and bile acid excretion. Lower hepatic TC and TG levels were found with GHE treatment. GHE reduced hepatic sterol regulatory element-binding proteins (SREBP including SREBP 1 and SREBP 2 protein expressions. The phosphorylation of adenosine monophosphate (AMP-activated protein kinase (AMPK protein expression in hamsters was decreased by the HF diet; however, GHE supplementation increased the phosphorylation of AMPK protein expression. Our results suggest that GHE may ameliorate lipid metabolism in hamsters fed a HF diet.

  8. Obeticholic acid raises LDL-cholesterol and reduces HDL-cholesterol in the Diet-Induced NASH (DIN) hamster model.

    Science.gov (United States)

    Briand, François; Brousseau, Emmanuel; Quinsat, Marjolaine; Burcelin, Rémy; Sulpice, Thierry

    2018-01-05

    The use of rat and mouse models limits the translation to humans for developing novel drugs targeting nonalcoholic steatohepatitis (NASH). Obeticholic acid (OCA) illustrates this limitation since its dyslipidemic effect in humans cannot be observed in these rodents. Conversely, Golden Syrian hamsters have a lipoprotein metabolism mimicking human dyslipidemia since it does express the cholesteryl ester transfer protein (CETP). We therefore developed a Diet-Induced NASH (DIN) hamster model and evaluated the impact of OCA. Compared with chow fed controls, hamsters fed for 20 weeks with a free-choice (FC) diet, developed obesity, insulin resistance, dyslipidemia and NASH (microvesicular steatosis, inflammation, hepatocyte ballooning and perisinusoidal to bridging fibrosis). After 20 weeks of diet, FC fed hamsters were treated without or with obeticholic acid (15mg/kg/day) for 5 weeks. Although a non-significant trend towards higher dietary caloric intake was observed, OCA significantly lowered body weight after 5 weeks of treatment. OCA significantly increased CETP activity and LDL-C levels by 20% and 27%, and reduced HDL-C levels by 20%. OCA blunted hepatic gene expression of Cyp7a1 and Cyp8b1 and reduced fecal bile acids mass excretion by 64% (P DIN hamster replicates benefits and side effects of OCA as observed in humans, and should be useful for evaluating novel drugs targeting NASH. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Coptisine attenuates obesity-related inflammation through LPS/TLR-4-mediated signaling pathway in Syrian golden hamsters.

    Science.gov (United States)

    Zou, Zong-Yao; Hu, Yin-Ran; Ma, Hang; Wang, Yan-Zhi; He, Kai; Xia, Shuang; Wu, Hao; Xue, Dong-Fang; Li, Xue-Gang; Ye, Xiao-Li

    2015-09-01

    It is known that obesity resulted from consumption of diets high in fat and calories and associated with a chronic low-grade inflammation. Because the fat, sterol and bile acid metabolism of male Syrian golden hamster are more similar to that of human, in the present study, high fat and high cholesterol (HFHC) induced obese hamsters were used to evaluate the anti-inflammation and hypolipidemic role of coptisine. The results showed that body weight, plasma lipid levels of total cholesterol (TC), triglyceride (TG), low density lipoprotein-cholesterol (LDL-c), very low density lipoprotein-cholesterol (VLDL-c), ApoB and pro-inflammatory cytokines including TNF-α, IL-6 and lipopolysaccharide (LPS) were significantly altered in hamsters fed with HFHC diet. A strong correlation was observed between the LPS level in serum and the level of LBP and pro-inflammatory cytokines. Coptisine from the concentrations of 60 to 700 mg/L dose-dependently inhibited Enterobacter cloacae growth, which can easily induce obesity and insulin resistance. The results of endotoxin neutralization assay suggest that coptisine is capable of reducing the LPS content under inflammation status. Real time RT-PCR analyses revealed that coptisine suppressed TLR-4 in visceral fat of hamsters and decreased CD14 expression in livers of hamsters. These encouraging findings make the development of coptisine a good candidate for preventing obesity-related diseases through the LPS/TLR-4-mediated signaling pathway. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. First genotoxicity study of Paraná river water from Argentina using cells from the clam Corbicula fluminea (Veneroida Corbiculidae and Chinese hamster (Cricetulus griseus Rodentia, Cricetidae K1 cells in the comet assay

    Directory of Open Access Journals (Sweden)

    Jacqueline D. Caffetti

    2008-01-01

    Full Text Available High concentrations of xenobiotics from urban and industrial wastes have contributed to the contamination of many aquatic environments. We used the comet assay to evaluate the genotoxic potential of water collected from the River Paraná, which receives a great deal of waste, at three points (Puerto Piray, Eldorado and Montecarlo in the Misiones Province of Argentina. The in vivo comet assay used 40 freshwater clams (Corbicula fluminea while the in vitro comet assay used Chinese hamster (Cricetulus griseus K1 cell (CHO-K1 cultures with the mutagen ethyl methanesulfonate (EMS as the positive control and phosphate buffered saline (PBS as the negative control. Both assays showed statistically significant differences between the three sampling sites in relation to the negative control, the results of this preliminary study indicating that at these three sites water from the Paraná River presents genotoxic potential.

  11. High-dose stabilized chlorite matrix WF10 prolongs cardiac xenograft survival in the hamster-to-rat model without inducing ultrastructural or biochemical signs of cardiotoxicity

    DEFF Research Database (Denmark)

    Hansen, A; Kemp, K; Kemp, E

    2001-01-01

    of high dose WF10 as a single drug regimen in the hamster-to-rat xenotransplantation model and searched for possible cardiotoxic side effects. WF10 prolonged cardiac xenograft survival, but did not induce tolerence or inhibit pathological signs of acute rejection. Hamsters from the donor population...

  12. Blood culture as a parameter of treatment effectiveness in experimental histoplasmosis of the hamster Hemocultivos como parametro de la eficacia del tratamiento de la histoplasmosis experimental en hamster

    Directory of Open Access Journals (Sweden)

    J. Finquelievich

    1995-04-01

    Full Text Available The aim of this study was to determine the value of blood culture as a parameter of treatment effectiveness in experimental histoplasmosis. A total of thirty five hamsters, weighing approximately 120g, were inoculated intracardiacly with 0.1 ml of a suspension containing 4 x 10(7 cells/ml of the yeast phase of H. capsulatum. Treatments were started one week after the infection and lasted for 3 weeks. The azoles, (itraconazole, saperconazole and fluconazole were administered once a day by gavage, at a dose of 8 mg/kg; Amphotericin B was given intraperitonealy every other day at a dose of 6mg/kg. Blood samples (1 ml were obtained by heart punction from the 4th day after infection and were seeded in Sabouraud honey-agar and BHI-agar. The hamsters that survived were killed one week after treatment completion and the following criteria were considered for treatment evaluation: 1 rate of spontaneous death, at the end of the experience; 2 microscopic examination of Giemsa smears from liver and spleen and 3 determination of CFU in spleen cultures. Amphotericin B was the most effective drug, with negative blood cultures at day 20, negative spleen cultures in all cases and all the animals survived until the end of the study. Fluconazole was the less effective drug, blood cultures were positive during the whole experience, spleen cultures showed a similar average of CFU when compared with the control animals and 42.8% of these animals died. Saperconazole and itraconazole showed a similar activity, with survival of all hamsters and negative blood cultures at 23 and 26 days respectively. Blood culture seems to be valuable parameter for treatments' evaluation in experimental histoplasmosis of the hamster.El propósito de esta investigación fue determinar el valor de los hemocultivos para juzgar la eficacia de los tratamientos en la histoplasmosis experimental. Treinta y cinco hamsters fueron inoculados por via intracardíaca con 0.1 ml de una suspensión de

  13. Antileishmanial activity of licochalcone A in mice infected with Leishmania major and in hamsters infected with Leishmania donovani

    DEFF Research Database (Denmark)

    Chen, M; Christensen, S B; Theander, T G

    1994-01-01

    This study was designed to examine the antileishmanial activity of the oxygenated chalcone licochalcone A in mice and hamsters infected with Leishmania parasites. Intraperitoneal administration of licochalcone A at doses of 2.5 and 5 mg/kg of body weight per day completely prevented lesion...... development in BALB/c mice infected with Leishmania major. Treatment of hamsters infected with L. donovani with intraperitoneal administration of licochalcone A at a dose of 20 mg/kg of body weight per day for 6 consecutive days resulted in a > 96% reduction of parasite load in the liver and the spleen...... compared with values for untreated control animals. The [3H]thymidine uptake by the parasites isolated from the treated hamsters was only about 1% of that observed in parasites isolated from the controls. Oral administration of licochalcone A at concentrations of 5 to 150 mg/kg of body weight per day for 6...

  14. The effects of radiation on antitumor efficacy of an oncolytic adenovirus vector in the Syrian hamster model.

    Science.gov (United States)

    Young, B A; Spencer, J F; Ying, B; Toth, K; Wold, W S M

    2013-09-01

    We report that radiation enhances the antitumor efficacy of the oncolytic adenovirus vector VRX-007 in Syrian hamster tumors. We used tumor-specific irradiation of subcutaneous tumors and compared treatment options of radiation alone or combined with VRX-007 and cyclophosphamide (CP). Radiation therapy further augmented the VRX-007-mediated inhibition of tumor growth, in both CP-treated and non-CP-treated hamsters, even though radiation did not lead to increased viral replication in tumors when compared with those treated with VRX-007 alone. Moreover, tumor growth inhibition was similar in tumors irradiated either 1 week before or after injection with VRX-007, which suggests that radiation exerts its antitumor effect independently from vector therapy. Thus, our results demonstrate that these two therapies do not have to be provided simultaneously to enhance their combined effectiveness against subcutaneous hamster tumors.

  15. Leishmania donovani infection induces anemia in hamsters by differentially altering erythropoiesis in bone marrow and spleen.

    Directory of Open Access Journals (Sweden)

    William P Lafuse

    Full Text Available Leishmania donovani is a parasite that causes visceral leishmaniasis by infecting and replicating in macrophages of the bone marrow, spleen, and liver. Severe anemia and leucopenia is associated with the disease. Although immune defense mechanisms against the parasite have been studied, we have a limited understanding of how L. donovani alters hematopoiesis. In this study, we used Syrian golden hamsters to investigate effects of L. donovani infection on erythropoiesis. Infection resulted in severe anemia and leucopenia by 8 weeks post-infection. Anemia was associated with increased levels of serum erythropoietin, which indicates the hamsters respond to the anemia by producing erythropoietin. We found that infection also increased numbers of BFU-E and CFU-E progenitor populations in the spleen and bone marrow and differentially altered erythroid gene expression in these organs. In the bone marrow, the mRNA expression of erythroid differentiation genes (α-globin, β-globin, ALAS2 were inhibited by 50%, but mRNA levels of erythroid receptor (c-kit, EpoR and transcription factors (GATA1, GATA2, FOG1 were not affected by the infection. This suggests that infection has a negative effect on differentiation of erythroblasts. In the spleen, erythroid gene expression was enhanced by infection, indicating that the anemia activates a stress erythropoiesis response in the spleen. Analysis of cytokine mRNA levels in spleen and bone marrow found that IFN-γ mRNA is highly increased by L. donovani infection. Expression of the IFN-γ inducible cytokine, TNF-related apoptosis-inducing ligand (TRAIL, was also up-regulated. Since TRAIL induces erythroblasts apoptosis, apoptosis of bone marrow erythroblasts from infected hamsters was examined by flow cytometry. Percentage of erythroblasts that were apoptotic was significantly increased by L. donovani infection. Together, our results suggest that L. donovani infection inhibits erythropoiesis in the bone marrow by

  16. Hypolipidemic Effect of Tomato Juice in Hamsters in High Cholesterol Diet-Induced Hyperlipidemia

    Directory of Open Access Journals (Sweden)

    Li-Chen Lee

    2015-12-01

    Full Text Available Tomato is a globally famous food and contains several phytonutrients including lycopene, β-carotene, anthocyanin, and flavonoids. The increased temperature used to produce tomato juice, ketchup, tomato paste and canned tomato enhances the bioactive composition. We aimed to verify the beneficial effects of processed tomato juice from Kagome Ltd. (KOT on hypolipidemic action in hamsters with hyperlipidemia induced by a 0.2% cholesterol and 10% lard diet (i.e., high-cholesterol diet (HCD. Male Golden Syrian hamsters were randomly divided into two groups for treatment: normal (n = 8, standard diet (control; and experimental (n = 32, HCD. The 32 hamsters were further divided into four groups (n = 8 per group to receive vehicle or KOT by oral gavage at 2787, 5573, or 13,934 mg/kg/day for six weeks, designated the HCD-1X, -2X and -5X groups, respectively. The efficacy and safety of KOT supplementation was evaluated by lipid profiles of serum, liver and feces and by clinical biochemistry and histopathology. HCD significantly increased serum levels of total cholesterol (TC, triacylglycerol (TG, high-density lipoprotein cholesterol (HDL-C, and low-density lipoprotein cholesterol (LDL-C, LDL-C/HDL-C ratio, hepatic and fetal TC and TG levels, and degree of fatty liver as compared with controls. KOT supplementation dose-dependently decreased serum TC, TG, LDL-C levels, LDL-C/HDL-C ratio, hepatic TC and TG levels, and fecal TG level. Our study provides experiment-based evidence to support that KOT may be useful in treating or preventing the onset of hyperlipidemia.

  17. Hypolipidemic Effects and Safety of Lactobacillus Reuteri 263 in a Hamster Model of Hyperlipidemia

    Directory of Open Access Journals (Sweden)

    Wen-Ching Huang

    2015-05-01

    Full Text Available We aimed to verify the beneficial effects of probiotic strain Lactobacillus reuteri 263 (Lr263 on hypolipidemic action in hamsters with hyperlipidemia induced by a 0.2% cholesterol and 10% lard diet (i.e., high-cholesterol diet (HCD. Male Golden Syrian hamsters were randomly divided into two groups: normal (n = 8, standard diet (control, and experimental (n = 32, a HCD. After a two-week induction followed by a six-week supplementation with Lr263, the 32 hyperlipidemic hamsters were divided into four groups (n = 8 per group to receive vehicle or Lr263 by oral gavage at 2.1, 4.2, or 10.5 × 109 cells/kg/day for 6 weeks, designated the HCD, 1X, 2X and 5X groups, respectively. The efficacy and safety of Lr263 supplementation were evaluated by lipid profiles of serum, liver and feces and by clinical biochemistry and histopathology. HCD significantly increased serum levels of total cholesterol (TC, triacylglycerol (TG cholesterol, high-density lipoprotein cholesterol (HDL-C, and low-density lipoprotein cholesterol (LDL-C, LDL-C/HDL-C ratio, hepatic and fetal TC and TG levels, and degree of fatty liver as compared with controls. Lr263 supplementation dose dependently increased serum HDL-C level and decreased serum TC, TG, LDL-C levels, LDL-C/HDL-C ratio, hepatic TC and TG levels, and fecal TG level. In addition, Lr263 supplementation had few subchronic toxic effects. Lr263 could be a potential agent with a hypolipidemic pharmacological effect.

  18. Effects of policosanols and phytosterols on lipid levels and cholesterol biosynthesis in hamsters.

    Science.gov (United States)

    Wang, Y W; Jones, P J H; Pischel, I; Fairow, C

    2003-02-01

    The current study was carried out to examine the effects of policosanols and phytosterols, alone and in combination, on lipid profiles, cholesterol biosynthesis, and tissue histopathological changes in hamsters. Fifty male Golden Syrian hamsters, weighing 100 to 120 g, were fed a regular rodent chow for 2 wk before being randomly assigned into 5 groups of 10 animals each fed semisynthetic diets for 4 wk. Group 1 was given a control diet that contained 0.25% cholesterol and 5% fat with a PUFA to saturated FA ratio of 0.4. Groups 2 to 5 were fed the control diet and given Octa-6 [a policosanol mixture from sugar cane wax, 25 mg/kg body weight (BW)], Ricewax (a policosanol mixture from rice wax with 50% being converted to the corresponding acids, 50 mg/kg BW), phytosterols (Cholestatin; 1,000 mg/kg BW), and Ricewax (50 mg/kg BW) plus phytosterols (1,000 mg/kg BW), respectively. The results showed that there was no difference between Octa-6 and Ricewax treatments in any of the lipid parameters measured, and both had similar levels of triglyceride (TG), total cholesterol (T-C), and HDL cholesterol (HDL-C) as the control. Octa-6 but not Ricewax increased (P = 0.03) non-HDL-C as compared with the control. Phytosterols reduced T-C (P < 0.0003) and HDL-C (P < 0.004) without a significant effect on TG and non-HDL-C as compared to the control. Ricewax plus phytosterols had effects similar to those with phytosterols alone. Free cholesterol synthetic rates were not different among the treatments. Policosanols or phytosterols did not show any toxic effects in liver, heart, brain, or kidney. Results suggest that, although phytosterols reduce T-C and HDL-C levels, policosanols have no significant favorable effect in changing lipid levels in hamsters.

  19. Olfactory ensheathing cells of hamsters, rabbits, monkeys, and mice express α-smooth muscle actin.

    Science.gov (United States)

    Rawji, Khalil S; Zhang, Shannon X; Tsai, Ying-Yu; Smithson, Laura J; Kawaja, Michael D

    2013-07-12

    Olfactory ensheathing cells (OECs) are the chief glial population of the mammalian olfactory nervous system, residing in the olfactory mucosa and at the surface of the olfactory bulb. We investigated the neurochemical features of OECs in a variety of mammalian species (including adult hamsters, rabbits, monkeys, and mice, as well as fetal pigs) using three biomarkers: α-smooth muscle actin (αSMA), S100β, and glial fibrillary acidic protein (GFAP). Mucosal and bulbar OECs from all five mammalian species express S100β. Both mucosal and bulbar OECs of monkeys express αSMA, yet only bulbar OECs of hamsters and only mucosal OECs of rabbits express αSMA as well. Mucosal OECs, but not bulbar OECs, also express GFAP in hamsters and monkeys; mice, by comparison, have only a sparse population of OECs expressing GFAP. Though αSMA immunostaining is not detected in OECs of adult mice, GFAP-expressing mucosal OECs isolated from adult mice do coexpress αSMA in vitro. Moreover, mucosal OECs from adult mutant mice lacking αSMA expression display perturbed cellular morphology (i.e., fewer cytoplasmic processes extending among the hundreds of olfactory axons in the olfactory nerve fascicles and nuclei having degenerative features). In sum, these findings highlight the efficacy of αSMA and S100β as biomarkers of OECs from a variety of mammalian species. These observations provide definitive evidence that mammalian OECs express the structural protein αSMA (at various levels of detection), which appears to play a pivotal role in their ensheathment of olfactory axons. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Delta FosB overexpression in the nucleus accumbens enhances sexual reward in female Syrian hamsters.

    Science.gov (United States)

    Hedges, V L; Chakravarty, S; Nestler, E J; Meisel, R L

    2009-06-01

    Repeated activation of the mesolimbic dopamine system results in persistent behavioral alterations accompanied by a pattern of neural plasticity in the nucleus accumbens (NAc). As the accumulation of the transcription factor Delta FosB may be an important component of this plasticity, the question addressed in our research is whether Delta FosB is regulated by sexual experience in females. We have shown that female Syrian hamsters, given sexual experience, exhibit several behavioral alterations including increased sexual efficiency with naïve male hamsters, sexual reward and enhanced responsiveness to psychomotor stimulants (e.g. amphetamine). We recently demonstrated that sexual experience increased the levels of Delta FosB in the NAc of female Syrian hamsters. The focus of this study was to explore the functional consequences of this induction by determining if the constitutive overexpression of Delta FosB by adeno-associated virus (AAV) vectors in the NAc could mimic the behavioral effects of sexual experience. Animals with AAV-mediated overexpression of Delta FosB in the NAc showed evidence of sexual reward in a conditioned place preference paradigm under conditions in which control animals receiving an injection of AAV-green fluorescent protein (GFP) into the NAc did not. Sexual behavior tests further showed that males paired with the AAV-Delta FosB females had increased copulatory efficiency as measured by the proportion of mounts that included intromission compared to males mated with the AAV-GFP females. These results support a role for Delta FosB in mediating natural motivated behaviors, in this case female sexual behavior, and provide new insight into the possible endogenous actions of Delta FosB.

  1. Experimental amoebic liver abscess in hamsters caused by trophozoites of a Brazilian strain of Entamoeba dispar.

    Science.gov (United States)

    Guzmán-Silva, Maria Angélica; Santos, Helena Lúcia Carneiro; Peralta, Regina Saramago; Peralta, José Mauro; de Macedo, Heloisa Werneck

    2013-05-01

    It has been claimed that amoebic molecules such as amoebapore, galactose/N-acetyl galactosamine inhibitable lectin, and cysteine proteases are responsible for host tissue destruction and are present in both pathogenic Entamoeba histolytica and non-pathogenic Entamoeba dispar. Some reports have provided evidence that after infection with E. dispar, pathological changes may occur in some humans. The aim of this study was to evaluate E. dispar pathogenicity by comparing it to the pathogenicity of E. histolytica through liver abscesses induced in hamsters. Syrian golden hamsters were challenged by intrahepatic inoculation with the 03C E. dispar strain or with two strains of E. histolytica (HM1:IMSS and EGG) to compare their virulence grades. As control groups, we used bacterial flora and Pavlova's modified medium. Lesions were verified at 1, 3 and 6 days after inoculation. Multiplex Polymerase Chain Reaction was performed to characterize each strain using EdP1/EdP2 and EhP1/EhP2 primers. The EGG and HM1:IMSS E. histolytica strains and 03C E. dispar were able to cause liver lesions. The EGG strain caused extensive hepatic abscesses, and trophozoites were found in the lesions throughout the three periods of study. The HM1:IMSS strain caused smaller abscesses when compared to EGG lesions; however, trophozoites were observed at 1 and 3 days after inoculation. The 03C E. dispar strain caused intermediate abscesses when compared to the others; trophozoites were observed in all periods analyzed. The EGG strain caused progressive evolution of the injury, which differed from the HM1:IMSS and 03C strains. These results strongly suggest that the 03C E. dispar strain is pathogenic in the experimental hamster model. Additional studies are necessary to identify potential factors that regulate the manifestation of virulence of this strain and others. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Hormonal changes and energy substrate availability during the hibernation cycle of Syrian hamsters.

    Science.gov (United States)

    Weitten, Mathieu; Robin, Jean-Patrice; Oudart, Hugues; Pévet, Paul; Habold, Caroline

    2013-09-01

    Animals have to adapt to seasonal variations in food resources and temperature. Hibernation is one of the most efficient means used by animals to cope with harsh winter conditions, wherein survival is achieved through a significant decrease in energy expenditure. The hibernation period is constituted by a succession of torpor bouts (hypometabolism and decrease in body temperature) and periodic arousals (eumetabolism and euthermia). Some species feed during these periodic arousals, and thus show different metabolic adaptations to fat-storing species that fast throughout the hibernation period. Our study aims to define these metabolic adaptations, including hormone (insulin, glucagon, leptin, adiponectin, GLP-1, GiP) and metabolite (glucose, free fatty acids, triglycerides, urea) profiles together with body composition adjustments. Syrian hamsters were exposed to varied photoperiod and temperature conditions mimicking different phases of the hibernation cycle: a long photoperiod at 20 °C (LP20 group), a short photoperiod at 20 °C (SP20 group), and a short photoperiod at 8 °C (SP8). SP8 animals were sampled either at the beginning of a torpor bout (Torpor group) or at the beginning of a periodic arousal (Arousal group). We show that fat store mobilization in hamsters during torpor bouts is associated with decreased circulating levels of glucagon, insulin, leptin, and an increase in adiponectin. Refeeding during periodic arousals results in a decreased free fatty acid plasma concentration and an increase in glycemia and plasma incretin concentrations. Reduced incretin and increased adiponectin levels are therefore in accordance with the changes in nutrient availability and feeding behavior observed during the hibernation cycle of Syrian hamsters. © 2013.

  3. Food deprivation and leptin prioritize ingestive and sex behavior without affecting estrous cycles in Syrian hamsters.

    Science.gov (United States)

    Schneider, Jill E; Casper, Janelle F; Barisich, Amanda; Schoengold, Candace; Cherry, Sandeep; Surico, Justine; DeBarba, Ashley; Fabris, Frank; Rabold, Elizabeth

    2007-03-01

    Energy consumption is critical for the energetically expensive processes related to reproduction, and thus, mechanisms that increase ingestive behavior are directly linked to reproductive success. Similarly, the mechanisms that inhibit hunger and ingestive behavior might be most adaptive when these mechanisms cause individuals to stop foraging, hoarding and eating in order to find and court potential mates. In the laboratory, ingestive behaviors are typically studied separately from reproductive behaviors even though it is likely that these behaviors evolved under conditions in which both food and mates were available. We examined the choice between paracopulatory and ingestive behaviors in a semi-natural environment in which both food and potential mates were available. Intact female Syrian hamsters showed a high preference for males on days 3 and 4 (day 4 being the day of ovulation and estrous behavior), and a 48-h period of food deprivation significantly decreased preference for sex and increased preference for eating and food hoarding on day 3 in 89% of the hamsters, although none became anestrous. The same period of food deprivation significantly decreased the level of vaginal marking without significant effects on plasma estradiol concentrations. Next, hamsters were either food deprived (FD) or fed ad libitum, and half of each group was treated with vehicle or the adipocyte hormone leptin. The percentage of females with a low preference for sex was significantly greater in the FD compared to the ad libitum-fed groups, and leptin treatment prevented this effect. Metabolic fuels, possibly acting through leptin and other hormones, might influence sensitivity to estradiol or enhance the downstream effects of estradiol, thereby increasing motivation for sex and decreasing the relative motivation to forage, hoard and eat food.

  4. Oxidative Damage Does Not Occur in Striped Hamsters Raising Natural and Experimentally Increased Litter Size.

    Directory of Open Access Journals (Sweden)

    Xiao-Ya Zhao

    Full Text Available Life-history theory assumes that animals can balance the allocation of limited energy or resources to the competing demands of growth, reproduction and somatic maintenance, while consequently maximizing their fitness. However, somatic damage caused by oxidative stress in reproductive female animals is species-specific or is tissue dependent. In the present study, several markers of oxidative stress (hydrogen peroxide, H2O2 and malonadialdehyde, MDA and antioxidant (catalase, CAT and total antioxidant capacity, T-AOC were examined in striped hamsters during different stages of reproduction with experimentally manipulated litter size. Energy intake, resting metabolic rate (RMR, and mRNA expression of uncoupling protein 1 (UCP1 in brown adipose tissue (BAT and UCP3 in skeletal muscle were also examined. H2O2 and MDA levels did not change in BAT and liver, although they significantly decreased in skeletal muscle in the lactating hamsters compared to the non-reproductive group. However, H2O2 levels in the brain were significantly higher in lactating hamsters than non-reproductive controls. Experimentally increasing litter size did not cause oxidative stress in BAT, liver and skeletal muscle, but significantly elevated H2O2 levels in the brain. CAT activity of liver decreased, but CAT and T-AOC activity of BAT, skeletal muscle and the brain did not change in lactating hamsters compared to non-reproductive controls. Both antioxidants did not change with the experimentally increasing litter size. RMR significantly increased, but BAT UCP1 mRNA expression decreased with the experimentally increased litter size, suggesting that it was against simple positive links between metabolic rate, UCP1 expression and free radicals levels. It may suggest that the cost of reproduction has negligible effect on oxidative stress or even attenuates oxidative stress in some active tissues in an extensive range of animal species. But the increasing reproductive effort may

  5. Ionizing radiation effect of phosphorus 32 on the bone marrow of hamsters

    International Nuclear Information System (INIS)

    Leite, J.B.F.; Marziona, F.

    1980-01-01

    105 hamsters were distributed in 3 groups: Group I with 5 animals, for control observations. Group II with 80 animals, which was injected with 1 milicurie of phosphorus 32 (0,12 ml of the solution) in only one dose, subperiosteum way, in the left femur. Group III with 20 animals was injected with 0,12 ml of phosphate's solution (substance without radioactivity) in only one dose, subperiosteum way, in the left femur. The animals were evaluated by the following parameters: clinical evaluation, macroscopy, optical microscopy of the femur, eletronic microscopy of the bone marrow and scintillographic captation of the femur, obtaining clinical, anatomopathologic and microscopic disturbances. (Author) [pt

  6. Postreplication gap filling in the DNA of X-ray-damaged Chinese hamster cells

    International Nuclear Information System (INIS)

    Koerner, I.; Malz, W.

    1975-01-01

    In X-irradiated Chinese hamster cells the newly synthesized DNA has a lower molecular weight than the DNA in control cells. This reduced molecular weight has been interpreted by gap induction opposite the lesions in the parental DNA strands. Within two hours these postreplication gaps were closed. With the aid of BrdUrd-photolys-technique it could be demonstrated that the gaps were filled by de novo synthesis. But we were not able to show a participation of parental DNA in the gap-filling process

  7. Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents.

    OpenAIRE

    Kaina, B; Lohrer, H; Karin, M; Herrlich, P

    1990-01-01

    Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of re...

  8. Variations in sensitivity of synchronized Chinese hamster cells to oxic and anoxic X-ray exposures

    International Nuclear Information System (INIS)

    Siracka, E.; Littbrand, B.; Clifton, K.H.; Revesz, L.

    1975-01-01

    V-79 Chinese hamster cells in monolayer cultures on glass surfaces were synchronized by treatment with hydroxyurea and then exposed at different times to X-rays in air or in oxygen-free argon. Survival determinations indicated that the oxygen enhancement ratio (OER) as expressed by the ratio of the respective D 0 values varied over a narrow range in the different phases of the cell cycle. These changes resulted from cyclic alterations in both aerobic and anaerobic D 0 values, possibly in n values. (author)

  9. Cell killing and mutation induction on Chinese hamster cells by photoradiations

    International Nuclear Information System (INIS)

    Lam, C.K.C.

    1982-11-01

    Applying radiation directly on cells, far-uv is more effective than black light, and black light is more effective than white light in inducing proliferative death and in inducing resistance to 6-thioguanine (6-TG), ouabain and diptheria toxin (DT). Gold light has no killing and mutagenic effects on CHO (Chinese hamster ovary) cells. Use of filters showed that a small percentage of shorter wavelengths in the far-uv region is responsible for most of the killing and mutagenic effects in the unfiltered broad spectra of black and white light

  10. Recovery from DNA synthesis in V 79 chinese hamster cells irradiated with UV light

    International Nuclear Information System (INIS)

    Ventura, A.M.

    1987-01-01

    Mammalian cells recover from DNA synthesis inhibition by UV light before most of the pyrimidine dimers have been removed from the genome. Most of the rodent cells show a deficient dimer excision repair compared with normal human fibroblasts. Despite this fact they recover efficiently from DNA synthesis inhibition after UV. In Chinese hamster V 79 cells was found that this recovery takes place in the absence of a significant excision repair, and it seems to be directly coupled to a recovery in the rate of movement of the replication fork. 120 refs, 31 figs. (author)

  11. Curcuma oil ameliorates insulin resistance & associated thrombotic complications in hamster & rat.

    Science.gov (United States)

    Singh, Vishal; Jain, Manish; Misra, Ankita; Khanna, Vivek; Prakash, Prem; Malasoni, Richa; Dwivedi, Anil Kumar; Dikshit, Madhu; Barthwal, Manoj Kumar

    2015-06-01

    Curcuma oil (C. oil) isolated from turmeric (Curcuma longa L.) has been shown to have neuro-protective, anti-cancer, antioxidant and anti-hyperlipidaemic effects in experimental animal models. However, its effect in insulin resistant animals remains unclear. The present study was carried out to investigate the disease modifying potential and underlying mechanisms of the C. oil in animal models of diet induced insulin resistance and associated thrombotic complications. Male Golden Syrian hamsters on high fructose diet (HFr) for 12 wk were treated orally with vehicle, fenofibrate (30 mg/kg) or C. oil (300 mg/kg) in the last four weeks. Wistar rats fed HFr for 12 wk were treated orally with C. oil (300 mg/kg) in the last two weeks. To examine the protective effect of C. oil, blood glucose, serum insulin, platelet aggregation, thrombosis and inflammatory markers were assessed in these animals. Animals fed with HFr diet for 12 wk demonstrated hyperlipidaemia, hyperglycaemia, hyperinsulinaemia, alteration in insulin sensitivity indices, increased lipid peroxidation, inflammation, endothelial dysfunction, platelet free radical generation, tyrosine phosphorylation, aggregation, adhesion and intravascular thrombosis. Curcuma oil treatment for the last four weeks in hamsters ameliorated HFr-induced hyperlipidaemia, hyperglycaemia, insulin resistance, oxidative stress, inflammation, endothelial dysfunction, platelet activation, and thrombosis. In HFr fed hamsters, the effect of C. oil at 300 mg/kg [ ] was comparable with the standard drug fenofibrate. Curcuma oil treatment in the last two weeks in rats ameliorated HFr-induced hyperglycaemia and hyperinsulinaemia by modulating hepatic expression of sterol regulatory element binding protein 1c (SREBP-1c), peroxisome proliferator-activated receptor-gamma co-activator 1 (PGC-1)α and PGC-1β genes known to be involved in lipid and glucose metabolism. High fructose feeding to rats and hamsters led to the development of insulin

  12. Saccharin-induced sister chromatid exchanges in Chinese hamster and human cells

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, S.; Rodin, B.

    1978-05-05

    Since the induction of sister chromatid exchanges in cultured cells has been shown to be the most sensitive mammalian system to detect the effects of mutagenic carcinogens, Chinese hamster ovary cells and human lymphocytes were exposed to the sodium saccharin found to induce bladder cancer in rats. Both that saccharin and a highly purified extract of it increased the yield of sister chromatid exchanges in both types of cells. The results, which were repeatable and statistically highly significant, indicated that the weak carcinogen, saccharin, is also mutagenic in the sense that it induces cytogenetic changes.

  13. Curcuma oil ameliorates insulin resistance & associated thrombotic complications in hamster & rat

    Directory of Open Access Journals (Sweden)

    Vishal Singh

    2015-01-01

    Full Text Available Background & objectives: Curcuma oil (C. oil isolated from turmeric (Curcuma longa L. has been shown to have neuro-protective, anti-cancer, antioxidant and anti-hyperlipidaemic effects in experimental animal models. However, its effect in insulin resistant animals remains unclear. The present study was carried out to investigate the disease modifying potential and underlying mechanisms of the C. oil in animal models of diet induced insulin resistance and associated thrombotic complications. Methods: Male Golden Syrian hamsters on high fructose diet (HFr for 12 wk were treated orally with vehicle, fenofibrate (30 mg/kg or C. oil (300 mg/kg in the last four weeks. Wistar rats fed HFr for 12 wk were treated orally with C. oil (300 mg/kg in the last two weeks. To examine the protective effect of C. oil, blood glucose, serum insulin, platelet aggregation, thrombosis and inflammatory markers were assessed in these animals. Results: Animals fed with HFr diet for 12 wk demonstrated hyperlipidaemia, hyperglycaemia, hyperinsulinaemia, alteration in insulin sensitivity indices, increased lipid peroxidation, inflammation, endothelial dysfunction, platelet free radical generation, tyrosine phosphorylation, aggregation, adhesion and intravascular thrombosis. Curcuma oil treatment for the last four weeks in hamsters ameliorated HFr-induced hyperlipidaemia, hyperglycaemia, insulin resistance, oxidative stress, inflammation, endothelial dysfunction, platelet activation, and thrombosis. In HFr fed hamsters, the effect of C. oil at 300 mg/kg [ ] was comparable with the standard drug fenofibrate. Curcuma oil treatment in the last two weeks in rats ameliorated HFr-induced hyperglycaemia and hyperinsulinaemia by modulating hepatic expression of sterol regulatory element binding protein 1c (SREBP-1c, peroxisome proliferator-activated receptor-gamma co-activator 1 (PGC-1α and PGC-1β genes known to be involved in lipid and glucose metabolism. Interpretation

  14. Some aspects of chemical protection of golden hamsters against ionizing radiation

    International Nuclear Information System (INIS)

    Sajkova, V.A.; Sverdlov, A.G.

    1983-01-01

    It was shown on Golden hamsters, which are characterized by high radioresistance of the intestine, that S-2-(#betta#-aminopropylaminoethyl) thiophosphorous acid (gammaphos) exerts a protective action against both X- and neutron-radiation although in the latter case the protection is less pronounced. In conditions of hibernation, the protective effect of gammaphos against X-radiation was not statistically reliable. Hibernation during exposure and at the postirradiation period increases considerably the radioresistance of animals. The influence of hibernation depends upon its duration

  15. Delineation of molecular pathways that regulate hepatic PCSK9 and LDL receptor expression during fasting in normolipidemic hamsters

    Science.gov (United States)

    Wu, Minhao; Dong, Bin; Cao, Aiqin; Li, Hai; Liu, Jingwen

    2015-01-01

    Background PCSK9 has emerged as a key regulator of serum LDL-C metabolism by promoting the degradation of hepatic LDL receptor (LDLR). In this study, we investigated the effect of fasting on serum PCSK9, LDL-C, and hepatic LDLR expression in hamsters and further delineated the molecular pathways involved in fasting-induced repression of PCSK9 transcription. Results Fasting had insignificant effects on serum total cholesterol and HDL-C levels, but reduced LDL-C, triglyceride and insulin levels. The decrease in serum LDL-C was accompanied by marked reductions of hepatic PCSK9 mRNA and serum PCSK9 protein levels with concomitant increases of hepatic LDLR protein amounts. Fasting produced a profound impact on SREBP1 expression and its transactivating activity, while having modest effects on mRNA expressions of SREBP2 target genes in hamster liver. Although PPARα mRNA levels in hamster liver were elevated by fasting, ligand-induced activation of PPARα with WY14643 compound in hamster primary hepatocytes did not affect PCSK9 mRNA or protein expressions. Further investigation on HNF1α, a critical transactivator of PCSK9, revealed that fasting did not alter its mRNA expression, however, the protein abundance of HNF1α in nuclear extracts of hamster liver was markedly reduced by prolonged fasting. Conclusion Fasting lowered serum LDL-C in hamsters by increasing hepatic LDLR protein amounts via reductions of serum PCSK9 levels. Importantly, our results suggest that attenuation of SREBP1 transactivating activity owing to decreased insulin levels during fasting is primarily responsible for compromised PCSK9 gene transcription, which was further suppressed after prolonged fasting by a reduction of nuclear HNF1α protein abundance. PMID:22954675

  16. Chemopreventive effects of a Tamarindus indica fruit extract against colon carcinogenesis depends on the dietary cholesterol levels in hamsters.

    Science.gov (United States)

    Martinello, Flavia; Kannen, Vinicius; Franco, João José; Gasparotto, Bianca; Sakita, Juliana Yumi; Sugohara, Atushi; Garcia, Sergio Britto; Uyemura, Sergio Akira

    2017-09-01

    Tamarind has significant antioxidant potential. We showed that tamarind protects hypercholesterolemic hamsters from atherosclerosis. Hypercholesterolemia might increase the risk of colon cancer. We investigated whether tamarind extract modulates the risk of colon cancer in hypercholesterolemic hamsters. Hamsters (n = 64) were given tamarind and a hypercholesterolemic diet for 8 weeks. The groups were the control, tamarind treatment, hypercholesterolemic, and hypercholesterolemic treated with tamarind groups. Half of each group was exposed to the carcinogen dimethylhydrazine (DMH) at the 8th week. All hamsters were euthanatized at the 10th week. In carcinogen-exposed hypercholesterolemic hamsters, tamarind did not alter the cholesterol or triglyceride serum levels, but it reduced biomarkers of liver damage (alanine transaminase [ALT], and aspartate aminotransferase [AST]). Tamarind decreased DNA damage in hepatocytes, as demonstrated by analysis with an anti-γH2A.X antibody. In liver and serum samples, we found that this fruit extract reduced lipid peroxidation (thiobarbituric acid reactive substances [TBARS]) and increased endogenous antioxidant mechanisms (glutathione peroxidase [GPx] and superoxide dismutase [SOD]). However, tamarind did not alter either lipid peroxidation or antioxidant defenses in the colon, which contrasts with DMH exposure. Moreover, tamarind significantly increased the stool content of cholesterol. Although tamarind reduced the risk of colon cancer in hypercholesterolemic hamsters that were carcinogenically exposed to DMH by 63.8% (Metallothionein), it was still ∼51% higher than for animals fed a regular diet. Staining colon samples with an anti-γH2A.X antibody confirmed these findings. We suggest that tamarind has chemoprotective activity against the development of colon carcinogenesis, although a hypercholesterolemic diet might impair this protection. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Electronegative LDL is linked to high-fat, high-cholesterol diet-induced nonalcoholic steatohepatitis in hamsters.

    Science.gov (United States)

    Lai, Yu-Sheng; Yang, Tzu-Ching; Chang, Po-Yuan; Chang, Shwu-Fen; Ho, Shu-Li; Chen, Hui-Ling; Lu, Shao-Chun

    2016-04-01

    The pathogenesis of nonalcoholic steatohepatitis (NASH), like that of atherosclerosis, involves lipid accumulation, inflammation and fibrosis. Recent studies suggest that oxidized LDL (oxLDL) may be a risk factor for NASH, but oxLDL levels were not directly measured in these studies. The aim of this study was to examine whether there was an association between electronegative LDL [LDL(-)], a mildly oxLDL found in the blood, and the development of NASH using two animal models. Golden Syrian hamsters and C57BL/6 mice were fed a high-fat, high-cholesterol (HFC) diet for 6 or 12weeks, then liver lipid and histopathology, plasma lipoprotein profile and LDL(-) levels were examined. The HFC-diet-fed hamsters and mice had similar levels of hepatic lipid but different histopathological changes, with microvesicular steatosis, hepatocellular hypertrophy, inflammation and bridging fibrosis in the hamsters, but only in mild steatohepatitis with low inflammatory cell infiltration in the mice. It also resulted in a significant increase in plasma levels of LDL cholesterol and LDL(-) in hamsters, but only a slight increase in mice. Moreover, enlarged Kupffer cells, LDL(-) and accumulation of unesterified cholesterol were detected in the portal area of HFC-diet-fed hamsters, but not HFC-diet-fed mice. An in vitro study showed that LDL(-) from HFC-diet-fed hamsters induced TNF-α secretion in rat Kupffer cell through a LOX-1-dependent pathway. Our results strongly suggest that LDL(-) is one of the underlying causes of hepatic inflammation and plays a critical role in the development of NASH. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. A preliminary investigation into the extent of increased radioresistance or hyper-radiosensitivity in cells of hamster cell lines known to be deficient in DNA repair

    International Nuclear Information System (INIS)

    Skov, K.; Marples, B.; Matthews, J.B.; Zhou, H.; Joiner, M.C.

    1994-01-01

    The response to low doses of X rays was assessed in cells of three hamster cell lines which are defective in DNA repair and was compared with their parental lines. Cells of the V79-derived double-strand break repair-deficient line XR-V15B showed no radioresistance in the 0.5-Gy range compared with the V79B wild type, but instead showed an exponential response. Cells of the single-strand break repair-deficient line EM9 showed hyper-radiosensitivity and exhibited increased radioresistance. Most interestingly, cells of the UV-20 cell line appeared to respond exponentially, as a continuation of the hyper-radiosensitive portion of the curve, with no evidence of increased radioresistance. This line is defective in an incision step of excision repair and is sensitive to crosslinking agents. Further studies are warranted to address the possible role of single- and double-strand break repair and excision repair in hyper-radiosensitivity and increased radioresistance. 24 refs., 4 figs

  19. Effects of food store quality on hibernation performance in common hamsters.

    Directory of Open Access Journals (Sweden)

    Carina Siutz

    Full Text Available Hibernating animals can adjust torpor expression according to available energy reserves. Besides the quantity, the quality of energy reserves could play an important role for overwintering strategies. Common hamsters are food-storing hibernators and show high individual variation in hibernation performance, which might be related to the quality of food hoards in the hibernacula. In this study, we tested the effects of food stores high in fat content, particularly polyunsaturated fatty acids (PUFAs, on hibernation patterns under laboratory conditions. Control animals received standard rodent pellets only, while in the other group pellets were supplemented with sunflower seeds. We recorded body temperature during winter using subcutaneously implanted data loggers, documented total food consumption during winter, and analysed PUFA proportions in white adipose tissue (WAT before and after the winter period. About half of the individuals in both groups hibernated and torpor expression did not differ between these animals. Among the high-fat group, however, individuals with high sunflower seeds intake strongly reduced the time spent in deep torpor. PUFA proportions in WAT decreased during winter in both groups and this decline was positively related to the time an individual spent in deep torpor. Sunflower seeds intake dampened the PUFA decline resulting in higher PUFA levels in animals of the high-fat group after winter. In conclusion, our results showed that common hamsters adjusted torpor expression and food intake in relation to the total energy of food reserves, underlining the importance of food hoard quality on hibernation performance.

  20. Carcinogenic effects of MGP-7 and B(a)P on the Hamster Cheek Pouch

    Energy Technology Data Exchange (ETDEWEB)

    Brandon, J.L.; Conti, C.J.; Goldstein, L.S.; DiGiovanni, J.; Gimenez-Conti, I.B. [University of Texas MD Anderson Cancer Center, Smithville, TX (United States). Dept. of Carcinogenesis

    2009-10-15

    This study was performed to examine the carcinogenic effects of benzo(a)pyrene (B(a)P) and manufactured gas plant (MGP) residues on the hamster cheek pouch (HCP). Syrian hamsters were treated topically with a suspension of 2%, 10%, or 20% B(a)P or 50% or 100% MGP-7 (a mixture of residues from 7 MGP sites) in mineral oil for eight (short-term study) and sixteen, twenty, twenty-eight, and thirty-two weeks (long-term study). The short-term study showed that B(a)P induced p53 protein accumulation, indicative of genotoxic damage, as well as increased cell proliferation, hyperplasia, and inflammation, which is usually associated with promotional activity. In contrast, the MGP-7 presented only marginal p53 accumulation and induction of BrdU incorporation. In the long-term experiments, animals treated with 2% and 10% of B(a)P continued to show p53 protein accumulation as well as hyperplasia and increased cell proliferation and inflammation. By thirty weeks, all the animals treated with B(a)P had a 100% incidence of squamous cell carcinoma (SCC). Animals treated with 50% and 100% MGP-7 showed only weak hyperplasia and a low proliferation rate and accumulation of p53 protein through thirty-two weeks. Benzo(a)pyrene was highly carcinogenic when used at adequate doses. Manufactured gas plant residue, however, was not carcinogenic in this model.

  1. Nasal associated lymphoid tissue of the Syrian golden hamster expresses high levels of PrPC.

    Directory of Open Access Journals (Sweden)

    Melissa D Clouse

    Full Text Available The key event in the pathogenesis of the transmissible spongiform encephalopathies is a template-dependent misfolding event where an infectious isoform of the prion protein (PrPSc comes into contact with native prion protein (PrPC and changes its conformation to PrPSc. In many extraneurally inoculated models of prion disease this PrPC misfolding event occurs in lymphoid tissues prior to neuroinvasion. The primary objective of this study was to compare levels of total PrPC in hamster lymphoid tissues involved in the early pathogenesis of prion disease. Lymphoid tissues were collected from golden Syrian hamsters and Western blot analysis was performed to quantify PrPC levels. PrPC immunohistochemistry (IHC of paraffin embedded tissue sections was performed to identify PrPC distribution in tissues of the lymphoreticular system. Nasal associated lymphoid tissue contained the highest amount of total PrPC followed by Peyer's patches, mesenteric and submandibular lymph nodes, and spleen. The relative levels of PrPC expression in IHC processed tissue correlated strongly with the Western blot data, with high levels of PrPC corresponding with a higher percentage of PrPC positive B cell follicles. High levels of PrPC in lymphoid tissues closely associated with the nasal cavity could contribute to the relative increased efficiency of the nasal route of entry of prions, compared to other routes of infection.

  2. Small Animal Models for Human Metapneumovirus: Cotton Rat is More Permissive than Hamster and Mouse

    Science.gov (United States)

    Zhang, Yu; Niewiesk, Stefan; Li, Jianrong

    2014-01-01

    Human metapneumovirus (hMPV) is the second most prevalent causative agent of pediatric respiratory infections worldwide. Currently, there are no vaccines or antiviral drugs against this virus. One of the major hurdles in hMPV research is the difficulty to identify a robust small animal model to accurately evaluate the efficacy and safety of vaccines and therapeutics. In this study, we compared the replication and pathogenesis of hMPV in BALB/c mice, Syrian golden hamsters, and cotton rats. It was found that BALB/c mice are not permissive for hMPV infection despite the use of a high dose (6.5 log10 PFU) of virus for intranasal inoculation. In hamsters, hMPV replicated efficiently in nasal turbinates but demonstrated only limited replication in lungs. In cotton rats, hMPV replicated efficiently in both nasal turbinate and lung when intranasally administered with three different doses (4, 5, and 6 log10 PFU) of hMPV. Lungs of cotton rats infected by hMPV developed interstitial pneumonia with mononuclear cells infiltrates and increased lumen exudation. By immunohistochemistry, viral antigens were detected at the luminal surfaces of the bronchial epithelial cells in lungs. Vaccination of cotton rats with hMPV completely protected upper and lower respiratory tract from wildtype challenge. The immunization also elicited elevated serum neutralizing antibody. Collectively, these results demonstrated that cotton rat is a robust small animal model for hMPV infection. PMID:25438015

  3. Intracellular pH in increased after transformation of Chinese hamster embryo fibroblasts

    International Nuclear Information System (INIS)

    Ober, S.S.; Pardee, A.B.

    1987-01-01

    These studies reveal that a series of tumorigenic Chinese hamster embryo fibroblast (CHEF) cell lines maintain an internal pH (pH/sub i/) that is 0.12 +/- 0.04 pH unit above that of the nontumorigenic CHEF/18 parental line. pH measurements were made with [ 14 C]-benzoic acid. This increase of pH/sub i/ in the tumorigenic CHEF cells is not due to autocrine growth factor production or to the persistent activation of pathways previously shown to modulate Na + /H + -antiporter activity present in the CHEF/18 line. These findings suggest that the defect in pH/sub i/ regulation in the tumorigenic CHEF/18 derivatives lies in the Na + /H + antiporter itself. Further studies to determine the biological significance of an increased pH/sub i/ show that the external pH (pH 0 )-dependence curve for initiation of DNA synthesis in the tumorigenic CHEF lines is shifted by approximately 0.2 pH unit toward acidic values relative to that of the nontumorigenic CHEF/18 parent. These data show a critical role for pH/sub i/ in the regulation of DNA synthesis in Chinese hamster embryo fibroblasts and demonstrate that aberrations in pH/sub i/ can contribute to the acquisition of altered growth properties

  4. Further data on conflict behaviour in golden hamsters: shifting between alternative sets of directional information.

    Science.gov (United States)

    Georgakopoulos, J; Etienne, A S

    1997-10-01

    Golden hamsters were trained to collect food in two differently patterned test boxes, linked to each other and to the nest by a T-shaped tube. To choose the correct goal direction from each box entrance the subjects could use either locomotor or visual cues. In test trials the central arm of the T-tube and the nest were rotated by 180°, setting visual and locomotor information in conflict. For one group of subjects, only the boxes were illuminated, whereas for a second group a general visual background was added. Locomotor information prevailed over visual for the majority of group 1 subjects. The second group gave the same weight to locomotor and visual cues in choosing the initial direction, but again depended more on locomotor cues for their final orientation. In a complementary test using the group 1 subjects, the hamsters entered the test box directly (without passing through the T-tube) and were therefore deprived of learned locomotor cues. Most animals chose the visually correct goal, showing that they had also associated the food locations with the visual cues. The experimental set-up favoured conflict resolution by shifting between locomotor and visual cues rather than by choosing compromise directions. This suggests that both kinds of information were processed simultaneously but could be used successively throughout each hoarding excursion.

  5. Nasal associated lymphoid tissue of the Syrian golden hamster expresses high levels of PrPC.

    Science.gov (United States)

    Clouse, Melissa D; Shikiya, Ronald A; Bartz, Jason C; Kincaid, Anthony E

    2015-01-01

    The key event in the pathogenesis of the transmissible spongiform encephalopathies is a template-dependent misfolding event where an infectious isoform of the prion protein (PrPSc) comes into contact with native prion protein (PrPC) and changes its conformation to PrPSc. In many extraneurally inoculated models of prion disease this PrPC misfolding event occurs in lymphoid tissues prior to neuroinvasion. The primary objective of this study was to compare levels of total PrPC in hamster lymphoid tissues involved in the early pathogenesis of prion disease. Lymphoid tissues were collected from golden Syrian hamsters and Western blot analysis was performed to quantify PrPC levels. PrPC immunohistochemistry (IHC) of paraffin embedded tissue sections was performed to identify PrPC distribution in tissues of the lymphoreticular system. Nasal associated lymphoid tissue contained the highest amount of total PrPC followed by Peyer's patches, mesenteric and submandibular lymph nodes, and spleen. The relative levels of PrPC expression in IHC processed tissue correlated strongly with the Western blot data, with high levels of PrPC corresponding with a higher percentage of PrPC positive B cell follicles. High levels of PrPC in lymphoid tissues closely associated with the nasal cavity could contribute to the relative increased efficiency of the nasal route of entry of prions, compared to other routes of infection.

  6. Combination of Praziquantel and Aspirin Minimizes Liver Pathology of Hamster Opisthorchis viverrini Infection Associated Cholangiocarcinoma.

    Science.gov (United States)

    Sudsarn, Pakkayanee; Boonmars, Thidarut; Ruangjirachuporn, Wipaporn; Namwat, Nisana; Loilome, Watcharin; Sriraj, Pranee; Aukkanimart, Ratchadawan; Nadchanan, Wonkchalee; Jiraporn, Songsri

    2016-01-01

    Opisthorchiasis is one of the major risk factors for cholangiocarcinoma (CCA) in northeastern Thailand. An effective drug for killing this parasite is praziquantel. Recently, several reports have shown that with frequent use, praziquantel may itself be a CCA risk and can cause liver cell damage from an immunopathological response after parasite death. Aspirin has many properties including anti-inflammation and anti-cancer. Therefore, we use of aspirin (As) and praziquantel (Pz) to improve hepatobiliary system function in hamsters infected with Opisthorchis viverrini (OV) and or administered N-nitrosodimethylamine (ND). Livers of OVNDAsPz, appeared healthy macroscopically, suggesting slow progression of cholangiocarcinoma evident by extent of fibrosis and bile duct cell proliferation was less than OVND although aggregations of inflammatory cells remained. Proliferating cell nuclear antigen (PCNA), cytokeratin 19 (CK19), and cancer antigen (CA19-9) staining were strongly positive in OVND, but were only slight in OVNDAs. Moreover, OVNDAsPz, appeared a few inflammatory infiltrations, bile duct proliferation, fibrosis and CCA area than the OVNDAs group. Thirty seven point five percent of hamster in this group could not develop CCA. These findings suggest that using aspirin combination with praziquantel treatment can improve the hepatobiliary system after O. viverrini infection and reduce the risk of CCA.

  7. Expression and Distribution of Leptospiral Outer Membrane Components during Renal Infection of Hamsters

    Science.gov (United States)

    Barnett, Jeanne K.; Barnett, Dean; Bolin, Carole A.; Summers, Theresa A.; Wagar, Elizabeth A.; Cheville, Norman F.; Hartskeerl, Rudy A.; Haake, David A.

    1999-01-01

    The outer membrane of pathogenic Leptospira species grown in culture media contains lipopolysaccharide (LPS), a porin (OmpL1), and several lipoproteins, including LipL36 and LipL41. The purpose of this study was to characterize the expression and distribution of these outer membrane antigens during renal infection. Hamsters were challenged with host-derived Leptospira kirschneri to generate sera which contained antibodies to antigens expressed in vivo. Immunoblotting performed with sera from animals challenged with these host-derived organisms demonstrated reactivity with OmpL1, LipL41, and several other proteins but not with LipL36. Although LipL36 is a prominent outer membrane antigen of cultivated L. kirschneri, its expression also could not be detected in infected hamster kidney tissue by immunohistochemistry, indicating that expression of this protein is down-regulated in vivo. In contrast, LPS, OmpL1, and LipL41 were demonstrated on organisms colonizing the lumen of proximal convoluted renal tubules at both 10 and 28 days postinfection. Tubular epithelial cells around the luminal colonies had fine granular cytoplasmic LPS. When the cellular inflammatory response was present in the renal interstitium at 28 days postinfection, LPS and OmpL1 were also detectable within interstitial phagocytes. These data establish that outer membrane components expressed during infection have roles in the induction and persistence of leptospiral interstitial nephritis. PMID:9916100

  8. Senile amyloidosis and neuron binding antibody in the aging Syrian hamster

    International Nuclear Information System (INIS)

    Blumenthal, H.T.; Musacchia, X.J.

    1985-01-01

    The effects of age, sex, and irradiation on the genesis of amyloidosis, neuron-binding antibody (NBA), and the concomitant appearance of these two phenomena were studied in a colony of Syrian hamsters. In nonirradiated controls amyloidosis increased in prevalence with age after 12 months, and prevalence was higher in females than in males. Irradiation had the effect of advancing the appearance of amyloidosis to the 7-12 months group but did not intensify the amyloidotic process. IgG binding to the nucleus or cytoplasm of neurons was rare, and, despite the fact that IgM and IgA binding to these structures was present in about one-third of the animals, there was neither an aging nor an irradiation effect. The only statistically significant findings with respect to the concomitant occurrence of amyloid and NBA were negative correlations between nuclear IgM and IgA binding and amyloidosis. Of the various species thus far studied, the hamster is the first in which there has been no aging effect in respect to NBA

  9. Adult wheel access interaction with activity and boldness personality in Siberian dwarf hamsters (Phodopus sungorus).

    Science.gov (United States)

    Kanda, L Leann; Abdulhay, Amir; Erickson, Caitlin

    2017-05-01

    Individual animal personalities interact with environmental conditions to generate differences in behavior, a phenomenon of growing interest for understanding the effects of environmental enrichment on captive animals. Wheels are common environmental enrichment for laboratory rodents, but studies conflict on how this influences behavior, and interaction of wheels with individual personalities has rarely been examined. We examined whether wheel access altered personality profiles in adult Siberian dwarf hamsters. We assayed animals in a tunnel maze twice for baseline personality, then again at two and at seven weeks after the experimental group was provisioned with wheels in their home cages. Linear mixed model selection was used to assess changes in behavior over time and across environmental gradient of wheel exposure. While animals showed consistent inter-individual differences in activity, activity personality did not change upon exposure to a wheel. Boldness also varies among individuals, and there is evidence for female boldness scores converging after wheel exposure, that is, opposite shifts in behavior by high and low boldness individuals, although sample size is too small for the mixed model results to be robust. In general, Siberian dwarf hamsters appear to show low behavioral plasticity, particularly in general activity, in response to running wheels. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Testicular development in Siberian hamsters depends on frequency and pattern of melatonin signals.

    Science.gov (United States)

    Flynn, A K; Freeman, D A; Zucker, I; Prendergast, B J

    2000-10-01

    We investigated the impact of frequency and pattern of melatonin signals on reproductive development in Siberian hamsters. Juvenile males gestated in short day lengths and housed in constant illumination to suppress melatonin secretion were infused with melatonin for 5 h either once or twice per day for 20 days. Melatonin infusions at either frequency produced equivalent increases in testes and body weights that exceeded those of animals infused with saline but were indistinguishable from those of hamsters transferred to long day lengths. The reproductive system appears to be maximally stimulated by a single short melatonin signal each day. Other animals kept from birth in a short photoperiod were treated 6 h after onset of darkness with the beta-adrenergic receptor antagonist DL-propranolol to shorten melatonin secretion on the night of injection but not on subsequent nights. This permitted interpolation of short nightly melatonin signals of 4-5 h duration against a background of long melatonin signals of 10-12 h duration on other nights. Treatment regimes that maintained a 1:1 ratio of short to long melatonin signals for 8 wk stimulated reproductive development; a 1:2 signal ratio, in each of three different patterns, was uniformly ineffective. The number of successive short melatonin signals had little influence on the interval across which successive melatonin signals were summated to influence photoperiodic traits. The neuroendocrine axis appears more responsive to short melatonin signal frequency than pattern for development of the summer phenotype.

  11. Efficacy of miltefosine for topical treatment of Acanthamoeba keratitis in Syrian hamsters.

    Science.gov (United States)

    Polat, Zubeyde Akın; Obwaller, Andreas; Vural, Ayse; Walochnik, Julia

    2012-02-01

    Acanthamoeba keratitis is a painful corneal infection and difficult to treat because no sufficiently efficient drug has yet been available. The aim of the study therefore was to assess the therapeutic potential of miltefosine on Acanthamoeba keratitis-infected hamster eyes. The cornea of hamsters were infected with Acanthamoeba hatchetti, a human corneal isolate. On the fifth day, all the cornea were microscopically examined in order to determine the degree of infections (G, from 0 to 3). Four groups were then prepared: miltefosine (160 μM); 0.1% propamidine isetionate plus 0.02% polyhexnide; infected control (0.05% ethanol in PBS) and a non-infected control (0.05% ethanol in PBS) groups. The treatment was continued for 28 days. After the treatment, the cornea were excised and used for Acanthamoeba culture to investigate the presence of Acanthamoeba growth. Miltefosine treatment yielded much higher cure scores than propamidine isetionate plus polyhexanide. On the last day of treatment, 85% of the miltefosine-treated eyes were graded as G0; no changes were observed in the uninfected control group eyes; G3 eyes showed only a partial improvement. Furthermore, no Acanthamoeba cells could be recovered from the miltefosine-treated eye samples. Miltefosine appeared to hold necessary therapeutic properties for the treatment of Acanthamoeba keratitis.

  12. Flow-system analysis of exfoliated pulmonary cells: results of initial characterization studies in hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Steinkamp, J.A.; Hansen, K.M.; Wilson, J.S.; Salzman, G.C.

    1976-01-01

    This paper summarizes results of preliminary experiments to develop cytological and biochemical indicators for estimating damage to respiratory cells in test animals exposed by inhalation to toxic agents associated with nonnuclear energy production, the specific goal being the application of advanced multiparameter flow-systems technologies to the detection of early atypical cellular changes in lung epithelium. Normal Syrian hamster lung cell samples composed of histiocytes, leukocytes, macrophages, ciliated columnar cells, and epithelial cells were stained with fluorescent dyes specific for different biochemical parameters and were analyzed in liquid suspension as they flowed through a chamber intersecting a laser beam of exciting light. Multiple sensors measured the total or two-color fluorescence and light scatter on a cell-by-cell basis. Cellular parameters proportional to optical measurements (i.e., cell size, DNA content, total protein, nonspecific esterase activity, nuclear and cytoplasmic diameters) were displayed as frequency distribution histograms. Lung cell samples were also separated according to various cytological parameters and identified microscopically. The basic operating features of the methodology are discussed briefly, along with specific examples of preliminary results illustrating the initial characterization of exfoliated pulmonary cells from normal hamsters. As the flow technology is adapted further to the analysis of respiratory cells, measurements of changes in physical and biochemical properties as a function of exposure to toxic agents will be performed.

  13. Individual recognition and odor in rat-like hamsters: behavioral responses and chemical properties.

    Science.gov (United States)

    Liu, Dingzhen; Huang, Ke-Jian; Zhang, Jian-Xu

    2011-11-01

    Individual recognition has been studied across a number of taxa and modalities; however, few attempts have been made to combine chemical and biological approaches and arrive at a more complete understanding of the use of secretions as signals. We combined behavioral habituation experiments with gas chromatography-mass spectrometry of glandular secretions from the left and right flank gland and midventral gland of the rat-like hamster, Tscheskia triton. We found that females became habituated to one scent and then could discriminate individuals via another scent source from the same individual only when familiar with the scent donor. However, this prior social interaction was not required for females to discriminate different individuals in single-stimulus habituation-dishabituation tests. Chemical analyses revealed a similarity in volatile compounds between the left and right flank gland and midventral gland scents. It appears that individually distinctive cues are integratively coded by a combination of both flank gland and midventral gland secretions, instead of a single scent, albeit animals show different preferences to the novel scent. Our results suggest that odors from the flank and midventral glands may provide information related to individuality and aid individual recognition in this species and confirm that prior interaction between individuals is a prerequisite for rat-like hamsters to form multi-odor memory of a particular conspecific.

  14. Piper species protect cardiac, hepatic and renal antioxidant status of atherogenic diet fed hamsters.

    Science.gov (United States)

    Agbor, Gabriel A; Akinfiresoye, Luli; Sortino, Julianne; Johnson, Robert; Vinson, Joe A

    2012-10-01

    Pre-clinical and clinical studies points to the use of antioxidants as an effective measure to reduce the progression of oxidative stress related disorders. The present study evaluate the effect of three Piper species (Piper guineense, Piper nigrum and Piper umbellatum) for the protection of cardiac, hepatic and renal antioxidant status of atherogenic diet fed hamsters. Hamsters were classified into eight groups: a normal control, atherogenic control and six other experimental groups (fed atherogenic diet supplemented with different doses of P. nigrum, P. guineense and P. umbellatum (1 and 0.25 g/kg) for 12 weeks. At the end of the feeding period the heart, liver and kidney from each group were analyzed for lipid profile and antioxidant enzymes activities. Atherogenic diet induced a significant (PPiper species significantly inhibited the alteration effect of atherogenic diet on the lipid profile and antioxidant enzymes activities. The Piper extracts may possess an antioxidant protective role against atherogenic diet induced oxidative stress in cardiac, hepatic and renal tissues. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Isolation and characterization of variant clones of Chinese hamster cells after treatment with irradiated 5-iodouridine

    International Nuclear Information System (INIS)

    Kuroda, Y.; Yokoiyama, A.; Kada, T.

    1975-01-01

    Variant clones were isolated from cultured Chinese hamster Don cells after treatment with irradiated 5-iodouridine. The following characters of a primary variant clone, C-11 and a secondary variant clone, C-24 were compared with those of the original clone C-1: colony-forming activity, growth rate in the presence of irradiated and unirradiated 5-iodouridine, distribution of chromosome numbers and cell cohesion. The variant clones C-11 and C-24 were partially resistant to unirradiated 5-iodouridine at lower concentration and C-24 cells were slightly resistant to short-term treatment with irradiated 5-iodouridine. Unlike clones C-1 and C-11, the variant clone C-24 showed no lag phase on growth in 5-iodouridine medium. The modal numbers of the chromosomes of all three clones were 22, like that of normal Chinese hamster diploid cells. Of the three clones, the variant C-24 cells showed the least mutual cohesion and the original C-1 cells showed the most. The possibility that an alteration in cellular membrane might be related to an increase in the resistance to radiosensitizing agents was discussed

  16. Protective effects of ursodeoxycholic acid on chenodeoxycholic acid-induced liver injury in hamsters.

    Science.gov (United States)

    Iwaki, Tomomichi; Ishizaki, Kaoru; Kinoshita, Shuji; Tanaka, Hideki; Fukunari, Atsushi; Tsurufuji, Makoto; Imada, Teruaki

    2007-10-07

    To investigate the effects of ursodeoxycholic acid (UDCA) on chenodeoxycholic acid (CDCA)-induced liver injury in hamsters, and to elucidate a correlation between liver injury and bile acid profiles in the liver. Liver injury was induced in hamsters by administration of 0.5% (w/w) CDCA in their feed for 7 d. UDCA (50 mg/kg and 150 mg/kg) was administered for the last 3 d of the experiment. At the end of the experiment, serum alanine aminotransferase (ALT) increased more than 10 times and the presence of liver injury was confirmed histologically. Marked increase in bile acids was observed in the liver. The amount of total bile acids increased approximately three-fold and was accompanied by the increase in hydrophobic bile acids, CDCA and lithocholic acid (LCA). UDCA (50 mg/kg and 150 mg/kg) improved liver histology, with a significant decrease (679.3 +/- 77.5 U/L vs 333.6 +/- 50.4 U/L and 254.3 +/- 35.5 U/L, respectively, P LCA, which accumulate and show the cytotoxicity in the liver.

  17. The influence of fasting and valence on the gastrointestinal absorption of plutonium in hamsters and rabbits

    International Nuclear Information System (INIS)

    Stather, J.W.; Harrison, J.D.; Smith, H.; Rodwell, P.; David, A.J.

    1980-01-01

    Plutonium ingested in contaminated food may be complexed to biological ligands in the food materials. Also, it is known that Pu in drinking water can exist as Pu(VI). A suggestion has been made, based on the results obtained by Weeks et al (Radiation Res., Vol. 4, 339,1956) that ingestion of Pu(VI) could mean that absorption of Pu would be substantially underestimated by using the value recommended by the ICRP. To further investigate the effect on absorption of both the oxidation state of ingested Pu and the nutritional state of the animal, Pu(IV) and Pu(VI) were administered to normally fed and fasted hamsters. The absorption of Pu(IV) was also measured in rabbits. Absorption of Pu in hamsters was not enhanced by prior oxidation to Pu(VI). However, increased absorption of both Pu(IV) and Pu(VI) was obtained in fasted animals. The results do not substantiate the high value for absorption of Pu(VI) obtained by Weeks et al, and support the value of 10sup(-2%) recommended by the ICRP for soluble forms of Pu. (author)

  18. Phenolphthalein induces chromosome aberrations in human and Chinese hamster liver cells (CHEL) cultured in vitro.

    Science.gov (United States)

    Biondi, O; Andreozzi, L; Amoruso, S; Motta, S

    2000-01-01

    Phenolphthalein is a nonprescription laxative agent that has been widely used during this century. Recent studies in animal models have shown that phenolphthalein has carcinogenic activity. In order to assess cytogenetic effects on human cells in vitro, we tested phenolphthalein in a chromosome aberration assay in human embryo cells derived from amniotic fluid. Our results show that phenolphthalein induces a significant increase in the frequency of chromosome aberrations in human cells. The lowest dose level at which the clastogenic effect is evident is 23.2 microg/ml. Similar positive results were obtained in a Chinese hamster liver cell line, which is metabolically competent to activate different classes of promutagens and procarcinogens into biologically active metabolites. Instead, parallel experiments in Chinese hamster ovary cells did not show any clastogenic effect due to phenolphthalein. These latter data suggested that phenolphthalein acts as a promutagen and must be metabolically activated to exert its clastogenic effect. Teratogenesis Carcinog. Mutagen. 20:209-217, 2000. Copyright 2000 Wiley-Liss, Inc.

  19. Effects of food store quality on hibernation performance in common hamsters.

    Science.gov (United States)

    Siutz, Carina; Nemeth, Matthias; Wagner, Karl-Heinz; Quint, Ruth; Ruf, Thomas; Millesi, Eva

    2017-01-01

    Hibernating animals can adjust torpor expression according to available energy reserves. Besides the quantity, the quality of energy reserves could play an important role for overwintering strategies. Common hamsters are food-storing hibernators and show high individual variation in hibernation performance, which might be related to the quality of food hoards in the hibernacula. In this study, we tested the effects of food stores high in fat content, particularly polyunsaturated fatty acids (PUFAs), on hibernation patterns under laboratory conditions. Control animals received standard rodent pellets only, while in the other group pellets were supplemented with sunflower seeds. We recorded body temperature during winter using subcutaneously implanted data loggers, documented total food consumption during winter, and analysed PUFA proportions in white adipose tissue (WAT) before and after the winter period. About half of the individuals in both groups hibernated and torpor expression did not differ between these animals. Among the high-fat group, however, individuals with high sunflower seeds intake strongly reduced the time spent in deep torpor. PUFA proportions in WAT decreased during winter in both groups and this decline was positively related to the time an individual spent in deep torpor. Sunflower seeds intake dampened the PUFA decline resulting in higher PUFA levels in animals of the high-fat group after winter. In conclusion, our results showed that common hamsters adjusted torpor expression and food intake in relation to the total energy of food reserves, underlining the importance of food hoard quality on hibernation performance.

  20. Hamster female protein, a pentameric oligomer capable of reassociation and hybrid formation

    International Nuclear Information System (INIS)

    Coe, J.E.; Ross, M.J.

    1987-01-01

    Syrian hamster female protein (SFP), a serum oligomer composed of five identical subunits, was reassociated in vitro monomer subunits. The reconstituted pentamer was genuine by morphologic, antigenic, and structural criteria. Another female protein (FP), a homologue from Armenian hamsters (AFP), also reassociated into a pentamer after dissociation with 5 M guanidine hydrochloride. These two FP's hybridized when a mixture of them was dissociated and then reassociated. Differences between the parent FP's were used to show that the recombinant pentamer contained monomer subunits from both SFP and AFP. Reassociation of both FP's was enhanced by increasing FP concentration and also by adding Ca 2+ during reassembly. The two FP's differed in their reassociation profile in that SFP was especially efficient in reassembly, whereas AFP was more dependent upon Ca 2+ . Female protein is a homologue of C-reactive protein and amyloid P component, and all of these proteins (pentraxins) share a similar structure. The in vitro dissociation-reassociation of female protein described herein may reflect an in vivo dissociation-reassociation which is functionally important and a common metabolic feature within this family of proteins

  1. Antioxidant Supplements Improve Profiles of Hepatic Oxysterols and Plasma Lipids in Butter-fed Hamsters

    Directory of Open Access Journals (Sweden)

    Johanne Poirier

    2010-01-01

    Full Text Available Hypercholesterolemia diets are associated with oxidative stress that may contribute to hypercholesterolemia by adversely affecting enzymatically-generated oxysterols involved in cholesterol homeostasis. An experiment was conducted to examine whether the cholesterol-lowering effects of the antioxidants selenium and α-tocopherol were related to hepatic oxysterol concentrations. Four groups of male Syrian hamsters (n = 7-8 were fed high cholesterol and saturated fat (0.46% cholesterol, 14.3% fat hypercholesterolemic semi-purified diets: 1 Control; 2 Control + α-tocopherol (67 IU all-racemic-α-tocopheryl-acetate/kg diet; 3 Control + selenium (3.4 mg selenate/kg diet; and 4 Control + α-tocopherol + selenium. Antioxidant supplementation was associated with lowered plasma cholesterol concentrations, decreased tissue lipid peroxidation and higher hepatic oxysterol concentrations. A second experiment examined the effect of graded selenium doses (0.15, 0.85, 1.7 and 3.4 mg selenate/kg diet on mRNA expression of the oxysterol-generating enzyme, hepatic 27-hydroxylase (CYP27A1, EC 1.14.13.15, in hamsters (n = 8-9 fed the hypercholesterolemic diets. Supplementation of selenium at 3.4 mg selenate/kg diet was not associated with increased hepatic 27-hydroxylase mRNA. In conclusion, the cholesterol lowering effects of selenium and α-tocopherol were associated with increased hepatic enzymatically generated oxysterol concentrations, which appears to be mediated via improved antioxidant status rather than increased enzymatic production.

  2. Multilevel systems biology modeling characterized the atheroprotective efficiencies of modified dairy fats in a hamster model.

    Science.gov (United States)

    Martin, Jean-Charles; Berton, Amélie; Ginies, Christian; Bott, Romain; Scheercousse, Pierre; Saddi, Alessandra; Gripois, Daniel; Landrier, Jean-François; Dalemans, Daniel; Alessi, Marie-Christine; Delplanque, Bernadette

    2015-09-01

    We assessed the atheroprotective efficiency of modified dairy fats in hyperlipidemic hamsters. A systems biology approach was implemented to reveal and quantify the dietary fat-related components of the disease. Three modified dairy fats (40% energy) were prepared from regular butter by mixing with a plant oil mixture, by removing cholesterol alone, or by removing cholesterol in combination with reducing saturated fatty acids. A plant oil mixture and a regular butter were used as control diets. The atherosclerosis severity (aortic cholesteryl-ester level) was higher in the regular butter-fed hamsters than in the other four groups (P metabolism" appeared central to atherogenic development relative to diets. The "vitamin E metabolism" cluster was the main driver of atheroprotection with the best performing transformed dairy fat. Under conditions that promote atherosclerosis, the impact of dairy fats on atherogenesis could be greatly ameliorated by technological modifications. Our modeling approach allowed for identifying and quantifying the contribution of complex factors to atherogenic development in each dietary setup. Copyright © 2015 the American Physiological Society.

  3. Comportamiento experimental del Sporothrix schenckii y la Leishmania mexicana en el hamster Experimental behavior of Sporothrix schenckii and Leishmania mexicana in hamsters

    Directory of Open Access Journals (Sweden)

    Luz Angela González de Polanía

    1990-10-01

    Full Text Available La descripción macroscópica del proceso de patogénesis en hamsters inoculados subcutáneamente en nariz con Sporothrix schenckii ó Leishmania mexicana spp. proporcionó bases para diferenciar estos dos microorganismos en un modelo animal utilizado comunmente para estudiarlos. Observaciones secuenciales durante 150 días permitieron afirmar que en las infecciones causadas por estos patógenos se presentaron edema y eritema como signos primarios, seguidos de alopecia, necrosis y ulceración. La producción de pus fué una característica distintiva para el S. schenckii. Estos signos clínicos se observaron más temprano en la esporotricosis que en la infección por L. mexicana, mostrando diferencias estadísticas significantes en días promedio de aparición. El presente trabajo muestra que las lesiones producidas tanto por el S. schenckii como la L. mexicana en este modelo experimental comparten signos clínicos, pero el tiempo de aparición de los mismos y su frecuencia relativa permiten diferenciarlas. Las condiciones de inoculación como: cepa de los microorganismos, dosis del inóculo, sitio y vía de inoculación, deben tenerse presentes en la evaluación de su comportamiento experimental.The macroscopic description of the pathogenic process of Sporothrix schenckii and Leishmania mexicana spp in hamsters inoculated subcutaneously in the nose provided bases for the differentiation of the behavior of these two microorganisms in a model frequently utilized for their study. Sequential observations over 150 days demonstrated that infections caused by these pathogens results initially in edema and erythema followed by loss of hair, necrosis and ulceration. The pus production was a characteristic presented only by S. schenckii. These clinical signs were observed earlier in sporotrichosis than in L. mexicana infection. Differences in the mean day of appearance were statistically significant. The lesions produced by S. schenckii and L. mexicana

  4. Características epidemiológicas da leishmaniose tegumentar americana em uma região endêmica do Estado da Bahia: II leishmaniose canina

    Directory of Open Access Journals (Sweden)

    Air C. Barretto

    1984-06-01

    Full Text Available Um inquérito em cães realizado na região de Três Braços, Bahia, mostrou que 3,0% de 98 animais tinham amastigotas em lesões de pele. Parasitos não foram encontrados em pele normal da orelha. De uma amostra selecionada de 13 cães, portadores de lesão cutânea ativa, nove (69,2% deles estavam comprovadamente infectados. Sete amostras de lesão produziram infecção em hamsters. O estudo biológico (crescimento em meio de cultura, evolução da lesão em hamster e desenvolvimento no tubo digestivo de Lutzomyia longipalpis identificou o parasito como pertencente ao complexo L. braziliensis. A caracterização bioquímica (mobilidade eletroforética de enzimas em placas de acetato de celulose e o estudo imunotaxonômico (anticorpos monoclonais definiram as amostras como L. braziliensis braziliensis. O papel do cão como um possível reservatório de L. b. braziliensis na região de Três Braços é discutido.

  5. Efficacy of UV-irradiated larval vaccine of Ancylostoma ceylanicum (Looss, 1911) in golden hamsters (Merocricetus auratus)

    International Nuclear Information System (INIS)

    Menon, S.; Bhopale, M.K.

    1985-01-01

    A vaccination trial in golden hamsters with UV-irradiated infective larvae of Ancylostoma ceylanicum was attempted. One oral vaccination of hamsters with 100 infective larvae irradiated by means of UV-tube (390 nm) at different time intervals induced the development of resistance. As the time exposure of irradiation was increased, there was a corresponding decrease in the subsequent worm establishment. A high level of protection afforded by larvae irradiated for 15 min UV-exposure was recorded giving 99.0% and 95.0% worm reduction against the challenge doses of 100 and 1000 normal larvae respectively. There was no marked difference in worm establishment in hamsters vaccinated either orally or subcutaneously, followed by oral challenge. In the vaccinated hamsters, the manifestations of resistance at 15 min UV-exposure were shown by marked reduction in worm establishment and highly reduced epg in pellets with significantly higher blood haemoglobin levels compared with those given normal larvae as vaccine and challenge controls. (author)

  6. Quantitative feature extraction from the Chinese hamster ovary bioprocess bibliome using a novel meta-analysis workflow

    DEFF Research Database (Denmark)

    Golabgir, Aydin; Gutierrez, Jahir M.; Hefzi, Hooman

    2016-01-01

    The scientific literature concerning Chinese hamster ovary (CHO) cells grows annually due to the importance of CHO cells in industrial bioprocessing of therapeutics. In an effort to start to catalogue the breadth of CHO phenotypes, or phenome, we present the CHO bibliome. This bibliographic...

  7. Blastocysts production and collection in albino Syrian hamster using superovulation and intrauterine artificial insemination in non-breeding season

    Directory of Open Access Journals (Sweden)

    A. Amiri Divani

    2017-06-01

    Full Text Available In vivo blastocyst production and collection using superovulation and intrauterine insemination was established in albino Syrian hamsters. Twenty female albino hamsters were injected pregnant mare serum gonadotropin (PMSG, 25 IU in non-breeding season and 48 h or 56 h later, 25 IU of human chorionic gonadotropin (hCG were injected. Both groups were divided into two subgroups of natural mating and artificial insemination. The former group was mated with a fertile male (1 male for 2 fe-males after hCG injection and in the next morning, the hamsters with vaginal plug were regarded as pregnant. In the artificial insemination group, intrauterine artificial insemination of 1×108 sperms was done 12 h after hCG injection. Blastocysts were counted at 3.5 days after mating or insemination. However, 48 h and 56 h hCG and natural mating and 48 h hCG and artificial insemination were without blastocyst; however the method of 56 h hCG and artificial insemination produced of 15±5 (mean and standard deviation blastocysts in each albino hamster in the winter.

  8. Multi-omic profiling of EPO-producing Chinese hamster ovary cell panel reveals metabolic adaptation to heterologous protein production

    DEFF Research Database (Denmark)

    Ley, Daniel; Kazemi Seresht, Ali; Engmark, Mikael

    2015-01-01

    Chinese hamster ovary (CHO) cells are the preferred production host for many therapeutic proteins. The production of heterologous proteins in CHO cells imposes a burden on the host cell metabolism and impact cellular physiology on a global scale. In this work, a multi-omics approach was applied...

  9. Effect of retinol and cigarette-smoke and condensate on dye-coupled intercellular communication between hamster tracheal epithelial cells

    NARCIS (Netherlands)

    Rutten, A.A.J.J.L.; Jongen, W.M.F.; Haan, L.H.J.de; Hendriksen, E.G.J.; Koeman, J.H.

    1988-01-01

    The dye-coupled intercellular communication across gap junctions in primary hamster tracheal epithelial cells has been studied in serum-free, hormone-supplemented medium. In the absence of vitamin A, non-cytotoxic concentrations of cigarette-smoke condensate (CSC) inhibited intercellular

  10. Combination therapies in adjuvant with topical ALA-mediated photodynamic therapy for DMBA-induced hamster buccal pouch premalignant lesions

    Science.gov (United States)

    Yang, Deng-Fu; Hsu, Yih-Chih

    2012-03-01

    In Taiwan, oral cancer has becomes the fastest growth male cancer disease due to the betel nut chewing habit combing with smoking and alcohol-drinking lifestyle of people. In order to eliminate the systemic phototoxic effect of 5-aminolevulinic acid (ALA), this study was designed to use a topical ALA-mediated PDT for treatment of DMBA-induced hamster buccal pouch precancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 10 to 12 weeks. Cancerous lesions were induced and proven by histological examination. These DMBA-induced cancerous lesions were used for testing the efficacy of topical ALA-mediated PDT. Before PDT, fluorescence spectroscopy was used to determine when ALA reached its peak level in the lesional epithelial cells after topical application of ALA gel. We found that ALA reached its peak level in precancerous lesions about 2.5 hrs after topical application of ALA gel. The cancerous lesions in hamsters were then treated with topical ALA -mediated PDT with light exposure dose of 150 J/cm2 using LED 635 nm fiber-guided light device. Visual examination demonstrated that adjuvant topical ALA -mediated PDT group has shown better therapeutic results in compared to those of non-adjuvant topical ALA-mediated PDT group for DMBA-induced hamster buccal pouch precancerous lesions.

  11. Topical photosan-mediated photodynamic therapy for DMBA-induced hamster buccal pouch early cancer lesions: an in vivo study

    Science.gov (United States)

    Hsu, Yih-Chih; Chang, Walter Hong-Shong; Chang, Junn-Liang; Liu, Kuang-Ting; Chiang, Chun-Pin; Liu, Chung-Ji; Chen, Chih-Ping

    2011-03-01

    Oral cancer has becomes the most prominent cancer disease in recent years in Taiwan. The reason is the betel nut chewing habit combing with smoking and alcohol-drinking lifestyle of people results in oral cancer becomes the fastest growth incident cancer amongst other major cancer diseases. In previous studies showed that photosan, haematoporphyrin derivative (HPD), has demonstrated effective PDT results on human head and neck disease studies. To avoid the systemic phototoxic effect of photosan, this study was designed to use a topical photosan-mediated PDT for treatment of DMBA-induced hamster buccal pouch cancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 10 to 12 weeks. Cancerous lesions were induced and proven by histological examination. These DMBA-induced cancerous lesions were used for testing the efficacy of topical photosan-mediated PDT. Before PDT, fluorescence spectroscopy was used to determine when photosan reached its peak level in the lesional epithelial cells after topical application of photosan gel. We found that photosan reached its peak level in cancerous lesions about 13.5 min after topical application of photosan gel. The cancerous lesions in hamsters were then treated with topical photosan-mediated PDT (fluence rate: 600 mW/cm2; light exposure dose 200 J/cm2) using the portable Lumacare 635 nm fiber-guided light device. Visual examination demonstrated that topical photosan-mediated PDT was an applicable treatment modality for DMBA-induced hamster buccal pouch cancerous lesions.

  12. Evidence that cell surface charge reduction modifes capillary red cell velocity-flux relationships in hamster cremaster muscle

    NARCIS (Netherlands)

    Vink, H.; Wieringa, P. A.; Spaan, J. A.

    1995-01-01

    1. From capillary red cell velocity (V)-flux (F) relationships of hamster cremaster muscle a yield velocity (VF = 0) can be derived at which red cell flux is zero. Red cell velocity becomes intermittent and/or red blood cells come to a complete standstill for velocities close to this yield velocity,

  13. Interphase death of dividing cells. Kinetics of death of cultured Chinese hamster fibroblasts after irradiation with various doses

    International Nuclear Information System (INIS)

    Kublik, L.N.; Veksler, A.M.; Ehjdus, L.Kh.

    1989-01-01

    In studying the kinetics of interphase death (ID) of cultured Chinese hamster cells after irradiation with doses of 100 to 800 Gy the authors showed an increase in the ID rate with increasing radiation dose; the presence of serum in the medium both during and after irradiation prevents the cell death

  14. Modification of potentially lethal damage in irradiated Chinese hamster V79 cells after incorporation of halogenated pyrimidines

    NARCIS (Netherlands)

    Franken, N. A.; van Bree, C. V.; Kipp, J. B.; Barendsen, G. W.

    1997-01-01

    Radiosensitization of exponentially growing and plateau phase Chinese hamster V79 cells by incorporation of halogenated pyrimidines (HP) was investigated for different culture conditions that influenced repair. For this purpose cells were grown for 72 h with 0, 1, 2 and 4 microM of chloro-(CldUrd),

  15. The influence of the wavelength of ultraviolet radiation on survival, mutation induction and DNA repair in irradiated Chinese hamster cells

    NARCIS (Netherlands)

    Zelle, B.; Reynolds, R.J.; Kottenhagen, M.J.; Schuite, A.; Lohman, P.H.M.

    1980-01-01

    Chinese hamster ovary cells were used to compare the cytotoxicity and mutagenicity of far-UV radiation emitted by a low-pressure mercury, germicidal lamp (wavelength predominantly 254 nm) with that of near-UV radiation emitted by a fluorescent lamp with a continuous spectrum (Westinghouse 'Sun

  16. Misoprostol-induced radioprotection of Syrian hamster embryo cells in utero from cell death and oncogenic transformation

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.C.; LaNasa, P.; Hanson, W.R. [Loyola Univ., Maywood, IL (United States)

    1994-07-01

    Misoprostol, a PGE analog, is an effective radioprotector of murine intestine and hematopoietic and hair cell renewal systems. The radioprotective nature of misoprostol was extended to examine its ability to influence clonogenic cell survival and induction of oncogenic transformation in Syrian hamster embryo cells exposed to X rays in utero and assayed in vitro. Hamsters in their 12th day of pregnancy were injected subcutaneously with misoprostal, and 2 h later the pregnant hamsters were exposed to graded doses of X rays. Immediately after irradiation, hamsters were euthanized and embryonic tissue was explanted into culture dishes containing complete growth medium. After a 2-week incubation period, clongenic cell survival and morphologically transformed foci were determined. Survival of misoprostol-treated SHE cells was increased and yielded a dose reduction factor of 1.5 compared to SHE cells treated with X rays alone. In contrast, radiation-induced oncogenic transformation of misoprostol-treated cells was reduced by a factor of 20 compared to cells treated with X rays alone. These studies suggest that misoprostol not only protects normal tissues in vivo from acute radiation injury, but also protects cells, to a large extent, from injury leading to transforming events. 26 refs., 6 figs., 2 tabs.

  17. Misoprostol-induced radioprotection of Syrian hamster embryo cells in utero from cell death and oncogenic transformation

    International Nuclear Information System (INIS)

    Miller, R.C.; LaNasa, P.; Hanson, W.R.

    1994-01-01

    Misoprostol, a PGE analog, is an effective radioprotector of murine intestine and hematopoietic and hair cell renewal systems. The radioprotective nature of misoprostol was extended to examine its ability to influence clonogenic cell survival and induction of oncogenic transformation in Syrian hamster embryo cells exposed to X rays in utero and assayed in vitro. Hamsters in their 12th day of pregnancy were injected subcutaneously with misoprostal, and 2 h later the pregnant hamsters were exposed to graded doses of X rays. Immediately after irradiation, hamsters were euthanized and embryonic tissue was explanted into culture dishes containing complete growth medium. After a 2-week incubation period, clongenic cell survival and morphologically transformed foci were determined. Survival of misoprostol-treated SHE cells was increased and yielded a dose reduction factor of 1.5 compared to SHE cells treated with X rays alone. In contrast, radiation-induced oncogenic transformation of misoprostol-treated cells was reduced by a factor of 20 compared to cells treated with X rays alone. These studies suggest that misoprostol not only protects normal tissues in vivo from acute radiation injury, but also protects cells, to a large extent, from injury leading to transforming events. 26 refs., 6 figs., 2 tabs

  18. Photoperiod and acute energy deficits interact on components of the thyroid hormone system in hypothalamic tanycytes of the Siberian hamster

    NARCIS (Netherlands)

    Herwig, Annika; Wilson, Dana; Logie, Tracy J.; Boelen, Anita; Morgan, Peter J.; Mercer, Julian G.; Barrett, Perry

    2009-01-01

    In the Siberian hamster, seasonal weight loss occurs gradually over many weeks during autumn and winter. This is driven by a regulatory mechanism that is able to integrate duration of exposure to short days (SDs) with the size of body energy reserves. After food restriction in SDs, followed by ad

  19. The distribution of plutonium-239 and americium-241 in the Syrian hamster following its intravenous administration as citrate

    International Nuclear Information System (INIS)

    Rodwell, P.; Stather, J.W.

    1978-01-01

    Actinide distribution in various tissues and the skeleton of hamsters by liquid scintillation counting or isotope dilution. For plutonium 57% of activity was concentrated in the skeleton and more than 90% in the liver and skeleton after seven days. For americium the liver retained more than 50% of total activity and 25% was excreted in urine within seven days. (U.K.)

  20. Spumiform basement membrane aberrations in the microvasculature of the midbrain periaqueductal gray region in hamster : Rostro-caudal pathogenesis?

    NARCIS (Netherlands)

    Gerrits, P.O.; Kortekaas, R.; de Weerd, Heleen; Luiten, P.G.M.; van der Want, J.J.L.; Veening, Jan

    2013-01-01

    Spumiform basement membrane degeneration (sbmd) is a specific kind of aberration present in the capillaries of the midbrain periaqueductal gray (PAG) region of the senescent hamster. These capillaries, separated by the ependymal cell layer, are bordering the Sylvian cerebral aqueduct. The aqueduct,

  1. Spumiform basement membrane aberrations in the microvasculature of the midbrain periaqueductal gray region in hamster: rostro-caudal pathogenesis?

    NARCIS (Netherlands)

    Gerrits, P.O.; Kortekaas, R.; Weerd, H. de; Luiten, P.G.M.; Want, J.J. van der; Veening, J.G.

    2013-01-01

    Spumiform basement membrane degeneration (sbmd) is a specific kind of aberration present in the capillaries of the midbrain periaqueductal gray (PAG) region of the senescent hamster. These capillaries, separated by the ependymal cell layer, are bordering the Sylvian cerebral aqueduct. The aqueduct,

  2. Transcriptome sequencing and development of an expression microarray platform for liver infection in adenovirus type 5-infected Syrian golden hamsters.

    Science.gov (United States)

    Ying, Baoling; Toth, Karoly; Spencer, Jacqueline F; Aurora, Rajeev; Wold, William S M

    2015-11-01

    The Syrian golden hamster is an attractive animal for research on infectious diseases and other diseases. We report here the sequencing, assembly, and annotation of the Syrian hamster transcriptome. We include transcripts from ten pooled tissues from a naïve hamster and one stimulated with lipopolysaccharide. Our data set identified 42,707 non-redundant transcripts, representing 34,191 unique genes. Based on the transcriptome data, we generated a custom microarray and used this new platform to investigate the transcriptional response in the Syrian hamster liver following intravenous adenovirus type 5 (Ad5) infection. We found that Ad5 infection caused a massive change in regulation of liver transcripts, with robust up-regulation of genes involved in the antiviral response, indicating that the innate immune response functions in the host defense against Ad5 infection of the liver. The data and novel platforms developed in this study will facilitate further development of this important animal model. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. The hypocholesterolemic and antiatherogenic effects of Cholazol H, a chemically functionalized insoluble fiber with bile acid sequestrant properties in hamsters.

    Science.gov (United States)

    Wilson, T A; Romano, C; Liang, J; Nicolosi, R J

    1998-08-01

    Cholazol H (Alpha-Beta Technology, Worcester, MA), a chemically functionalized, insoluble dietary fiber with bile acid sequestrant properties, was studied in 30 male F1 B Golden Syrian hamsters for its effect on plasma lipid concentrations and early atherogenesis in experiment 1. In experiment 2, 30 male Golden Syrian hamsters were studied for the effects on plasma lipids and fecal excretion of bile acids. In experiment 1, three groups of 10 hamsters each were fed a chow-based hypercholesterolemic diet supplemented with 5% coconut oil and 0.1% cholesterol for 6 weeks. After 6 weeks, hamsters were continued on the diet with either 0% drug (hypercholesterolemic diet [HCD]), 0.5% cholestyramine (CSTY), or 0.5% Cholazol H for 8 weeks. Fasting plasma lipids were measured at weeks 6, 10, and 14, and early atherosclerosis (fatty streak formation) was measured at week 14. Relative to HCD, CSTY and Cholazol H significantly lowered plasma total cholesterol (TC) (-37%, P coconut oil and 0.05% cholesterol and either 0% drug HCD, 0.5% CSTY, or 0.5% Cholazol H for 4 weeks. Fasting plasma lipids were measured at weeks 2 and 4, and fecal bile acids were measured at week 4. Both Cholazol H and CSTY were equally effective in significantly lowering plasma TC (-16%, P < .003, and -13%, P < .01, respectively) and nonHDL-C (-22%, P < .004, and -18%, P < .02, respectively), with no significant effect on HDL-C and TG relative to HCD. Cholazol H and CSTY produced a significantly greater concentration of fecal total bile acids (39%, P < .001, and 28%, P < .002, respectively) relative to HCD. Also, there was a 48% (P < .002) and 65% (P < .001) greater fecal concentration of cholic acid (CA) for Cholazol H-treated hamsters compared with HCD- and CSTY-treated hamsters, respectively. Cholazol H also significantly increased fecal concentration of deoxycholic acid (DCA; 56%, P < .02) compared with HCD. In summary, Cholazol H is as effective as CSTY for prevention of diet

  4. Cytotoxicity and Genotoxicity of Panel of Single- and Multiwalled Carbon Nanotubes: In Vitro Effects on Normal Syrian Hamster Embryo and Immortalized V79 Hamster Lung Cells

    Directory of Open Access Journals (Sweden)

    C. Darne

    2014-01-01

    Full Text Available Carbon nanotubes (CNTs belong to a specific class of nanomaterials with unique properties. Because of their anticipated use in a wide range of industrial applications, their toxicity is of increasing concern. In order to determine whether specific physicochemical characteristics of CNTs are responsible for their toxicological effects, we investigated the cytotoxic and genotoxic effects of eight CNTs representative of each of the commonly encountered classes: single- SW-, double- DW-, and multiwalled (MW CNTs, purified and raw. In addition, because most previous studies of CNT toxicity were conducted on immortalized cell lines, we decided to compare results obtained from V79 cells, an established cell line, with results from SHE (Syrian hamster embryo cells, an easy-to-handle normal cell model. After 24 hours of treatment, MWCNTs were generally found to be more cytotoxic than SW- or DWCNTs. MWCNTs also provoked more genotoxic effects. No correlation could be found between CNT genotoxicity and metal impurities, length, surface area, or induction of cellular oxidative stress, but genotoxicity was seen to increase with CNT width. The toxicity observed for some CNTs leads us to suggest that they might also act by interfering with the cell cycle, but no significant differences were observed between normal and immortalized cells.

  5. Testosterone, androstenedione, and 5alpha-dihydrotestosterone on male sexual behavior and penile spines in the hamster.

    Science.gov (United States)

    Arteaga-Silva, M; Vigueras-Villaseñor, R M; Retana-Márquez, S; Hernández-González, M; Chihuahua-Serrano, C; Bonilla-Jaime, H; Contreras, J L; Moralí, G

    2008-06-09

    The expression of masculine sexual behavior (MSB) in male hamsters is optimally stimulated by aromatizable androgens like androstenedione (AD) and testosterone (T), while the non-aromatizable androgen, 5alpha-dihydrotestosterone (DHT), exerting potent androgenic peripheral effects, only in high doses maintains MSB after castration. No data exist on the ability of these androgens to restore long intromissions after castration. In this study, AD, T, and DHT were administered to four-week gonadectomized, sexually experienced male hamsters, for three weeks, in doses of 25 microg/day or up to 1000 microg/day to compare their potency in restoring MSB, penile size, and penile spines growth. Plasma levels of these steroids and the metabolites estrone and estradiol, were determined at the end of the treatment period. Gonadectomy completely suppressed MSB and induced a regression of penile spines. AD was more potent than T in restoring MSB, ejaculatory behavior being displayed by most castrated subjects with a lower dose of AD (50 microg/day) than of T (300 microg/day), and long intromissions being shown by all AD-treated castrated hamsters but only by 20% of T-treated ones, when doses of 1000 microg/day were given. DHT did not stimulate any copulatory response. The three androgens, even at the lowest dose, partially stimulated penis and penile epithelium growth, DHT showing the highest potency. Treatment of castrated hamsters with AD (50 microg/day), restored steroid levels to similar values as those of intact animals. These results show that AD and T restored MSB even with a partial stimulation of penile spines growth, AD being more potent than T. In contrast, DHT did not restore MSB in the hamster in spite of its peripheral androgenic potency.

  6. Evaluation of efficacy of prion reduction filters using blood from an endogenously infected 263K scrapie hamster model.

    Science.gov (United States)

    McLeod, Neil P; Nugent, Philip; Dixon, Douglas; Dennis, Mike; Cornwall, Mark; Mallinson, Gary; Watkins, Nicholas; Thomas, Stephen; Sutton, J Mark

    2015-10-01

    The P-Capt prion reduction filter (MacoPharma) removes prion infectivity in model systems. This independent evaluation assesses prion removal from endogenously infected animal blood, using CE-marked P-Capt filters, and replicates the proposed use of the filter within the UK Blood Services. Two units of blood, generated from 263K scrapie-infected hamsters, were processed using leukoreduction filters (LXT-quadruple, MacoPharma). Approximately 100 mL of the removed plasma was added back to the red blood cells (RBCs) and the blood was filtered through a P-Capt filter. Samples of unfiltered whole blood, the prion filter input (RBCs plus plasma and SAGM [RBCPS]), and prion-filtered leukoreduced blood (PFB) were injected intracranially into hamsters. Clinical symptoms were monitored for 500 ± 1 day, and brains were assessed for spongiosis and prion protein deposit. In Filtration Run 1, none of the 50 challenged animals were diagnosed with scrapie after inoculation with the RBCPS fraction, while two of 190 hamsters injected with PFB were infected. In Filtration Run 2, one of 49 animals injected with RBCPS and two of 193 hamsters injected with PFB were infected. Run 1 reduced the infectious dose (ID) by 1.467 log (>1.187 log and <0.280 log for leukoreduction and prion filtration, respectively). Run 2 reduced prion infectivity by 1.424 log (1.127 and 0.297 log, respectively). Residual infectivity was estimated at 0.212 ± 0.149 IDs/mL (Run 1) and 0.208 ± 0.147 IDs/mL (Run 2). Leukoreduction removed the majority of infectivity from 263K scrapie hamster blood. The P-Capt filter removed a proportion of the remaining infectivity, but residual infectivity was observed in two independent processes. © 2015 AABB.

  7. Sustained melatonin treatment blocks body mass, pelage, reproductive, and fever responses to short day lengths in female Siberian hamsters.

    Science.gov (United States)

    Fenn, Ashley M; Fonken, Laura K; Nelson, Randy J

    2011-09-01

    Winter imposes physiological challenges on individuals including increased thermoregulatory demands, risk of infection, and decreased food availability. To survive these challenges, animals living outside the tropics must appropriately distribute their energetic costs across the year, including reproduction and immune function. Individuals of many species use the annual cycle of changing day lengths (photoperiod), which is encoded by the nightly duration of melatonin secretion, to adjust physiology. Siberian hamsters exposed to short days (SD) (long nights/prolonged endogenous melatonin secretion) enhance some aspects of immune function, but curtail other energetically expensive immune functions including the febrile response. The purpose of this study was twofold. First, we determined whether sustained melatonin treatment would inhibit the development of the SD phenotype in female hamsters as it does in males. Second, we examined whether the SD attenuation of fever would be blocked by continuous exposure to exogenous melatonin. Hamsters were implanted with melatonin or empty capsules, housed in either long days (LD) or SD for 8-9 weeks, and then challenged with lipopolysaccharide; body temperature and locomotor activity were recorded. Unlike hamsters with empty capsules, hamsters with melatonin implants did not respond to SD and maintained a LD phenotype including summer-like spleen, uterine and body masses, and pelage characteristics. Further, sustained melatonin treatment blocked the SD attenuation of febrile responses and prolonged the behavioral components of the sickness response. These results suggest that the daily fluctuations in endogenous melatonin may be masked by continuous exposure to exogenous melatonin, thus inhibiting functional photoperiodic responses to SD. © 2011 John Wiley & Sons A/S.

  8. The gingival vein as a minimally traumatic site for multiple blood sampling in guinea pigs and hamsters.

    Science.gov (United States)

    Rodrigues, Mariana Valotta; de Castro, Simone Oliveira; de Albuquerque, Cynthia Zaccanini; Mattaraia, Vânia Gomes de Moura; Santoro, Marcelo Larami

    2017-01-01

    Laboratory animals are still necessary in scientific investigation and vaccine testing, but while novel methodological approaches are not available for their replacement, the search for new, humane, easy, and painless methods is necessary to diminish their stress and pain. When multiple blood samples are to be collected from hamsters and guinea pigs, the number of available venipuncture sites-which are greatly diminished in these species in comparison with other rodents due to the absence of a long tail-, harasses animal caregivers and researchers. Thus, this study aimed to evaluate if gingival vein puncture could be used as an additional route to obtain multiple blood samples from anesthetized hamsters and guinea pigs in such a way that animal behavior, well-being or hematological parameters would not be altered. Thus, twelve anesthetized Syrian golden hamsters and English guinea pigs were randomly allocated in two groups: a control group, whose blood samples were not collected, and an experimental group in which blood samples (200 microliters) were collected by gingival vein puncture at weekly intervals over six weeks. Clinical assessment, body weight gain and complete blood cell count were evaluated weekly, and control and experimental animals were euthanized at week seven, when the mentolabial region was processed to histological analyses. Multiple blood sampling from the gingival vein evoked no clinical manifestations or alteration in the behavioral repertoire, nor a statistically significant difference in weight gain in both species. Guinea pigs showed no alteration in red blood cell, leukocyte or platelet parameters over time. Hamsters developed a characteristic pattern of age-related physiological changes, which were considered normal. Histological analyses showed no difference in morphological structures in the interdental gingiva, confirming that multiple blood sampling is barely traumatic. Thus, these results evidence that blood collection from multiple

  9. Binding kinetics of Clostridium difficile toxins A and B to intestinal brush border membranes from infant and adult hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Rolfe, R.D. (Texas Tech Univ. Health Sciences Center, Lubbock (USA))

    1991-04-01

    This study was undertaken to determine if the relative resistance of neonates and infants to Clostridium difficile-associated intestinal disease can be related to age-dependent differences in intestinal receptors for C. difficile toxins A and B. Brush border membranes (BBMs) from the small intestines of adult and infant hamsters were examined for their ability to bind radiolabeled toxins A and B. (125I)toxin A bound to both infant and adult hamster BBMs at physiological temperature, whereas (125I)toxin B did not bind to the BBMs under any of the conditions examined. The number of (125I)toxin A molecules bound at saturation was approximately 4 x 10(10) per micrograms of membrane protein for adult BBMs and 1 x 10(11) per micrograms of membrane protein for infant BBMs. Scatchard plot analysis suggested the presence of a single class of toxin A binding sites on both infant and adult hamster BBMs. Maximal binding capacity and Kd values were 0.63 pmol/mg of protein and 66.7 nM, respectively, for the infant BBMs, and 0.24 pmol/mg of protein and 27 nM, respectively, for the adult BBMs. Sodium dodecyl sulfate-polyacrylamide gel electrophoretic analyses of extracted BBM proteins revealed differences in the proteins of infant and adult BBMs. However, there were not any detectable differences in the protein bands which bound (125I)toxin A between infant and adult hamsters. The results from these investigations indicate that differences in the binding kinetics of toxins A and/or B to infant and adult hamster BBMs do not account for the observed differences in their susceptibility to C. difficile-associated intestinal disease.

  10. New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication

    OpenAIRE

    Brown, Paul; Rau, Edward H.; Johnson, Bruce K.; Bacote, Alfred E.; Gibbs, Clarence J.; Gajdusek, D. Carleton

    2000-01-01

    One-gram samples from a pool of crude brain tissue from hamsters infected with the 263K strain of hamster-adapted scrapie agent were placed in covered quartz-glass crucibles and exposed for either 5 or 15 min to dry heat at temperatures ranging from 150°C to 1,000°C. Residual infectivity in the treated samples was assayed by the intracerebral inoculation of dilution series into healthy weanling hamsters, which were observed for 10 months; disease transmissions were ...

  11. Transmissibility of H-Type Bovine Spongiform Encephalopathy to Hamster PrP Transgenic Mice.

    Directory of Open Access Journals (Sweden)

    Hiroyuki Okada

    Full Text Available Two distinct forms of atypical bovine spongiform encephalopathies (H-BSE and L-BSE can be distinguished from classical (C- BSE found in cattle based on biochemical signatures of disease-associated prion protein (PrPSc. H-BSE is transmissible to wild-type mice-with infected mice showing a long survival period that is close to their normal lifespan-but not to hamsters. Therefore, rodent-adapted H-BSE with a short survival period would be useful for analyzing H-BSE characteristics. In this study, we investigated the transmissibility of H-BSE to hamster prion protein transgenic (TgHaNSE mice with long survival periods. Although none of the TgHaNSE mice manifested the disease during their lifespan, PrPSc accumulation was observed in some areas of the brain after the first passage. With subsequent passages, TgHaNSE mice developed the disease with a mean survival period of 220 days. The molecular characteristics of proteinase K-resistant PrPSc (PrPres in the brain were identical to those observed in first-passage mice. The distribution of immunolabeled PrPSc in the brains of TgHaNSE mice differed between those infected with H-BSE as compared to C-BSE or L-BSE, and the molecular properties of PrPres in TgHaNSE mice infected with H-BSE differed from those of the original isolate. The strain-specific electromobility, glycoform profiles, and proteolytic cleavage sites of H-BSE in TgHaNSE mice were indistinguishable from those of C-BSE, in which the diglycosylated form was predominant. These findings indicate that strain-specific pathogenic characteristics and molecular features of PrPres in the brain are altered during cross-species transmission. Typical H-BSE features were restored after back passage from TgHaNSE to bovinized transgenic mice, indicating that the H-BSE strain was propagated in TgHaNSE mice. This could result from the overexpression of the hamster prion protein.

  12. No-Disjunction and loss of anafasica Hamster-human hybrid embryos of two cells

    International Nuclear Information System (INIS)

    Ponsa, I.; Tusell, L.; Alvarez, R.; Genesca, A.; Miro, R.; Egozcue, J.

    1998-01-01

    To investigate the possible effect anafasica the ionizing radiations in masculine germinal cells a new test it has been developed combining two techniques, the fecundation interspecific gives ovocitos hamster without area pellucid with human sperms and the fluorescent in situ hybridization in cells in interface using probes gives DNA specific centrometricas. Analyzing the segregation gives the chromosomes marked in the embryos two cells, you can detect the reciprocal products easily an anomalous segregation. Give this way the recount the fluorescent signs in the nuclei siblings and in the micronucleus it provides an esteem the due aneuploidy to errors meiotic or premiotic, with this way the resulting aneuploidy the errors in the first division mitotic the embryos, as much no-disjunction as lost anafasica

  13. Effect of caffeine on the ultraviolet light induction of SV40 virus from transformed hamster cells

    International Nuclear Information System (INIS)

    Zamansky, G.B.; Kleinman, L.F.; Little, J.B.; Black, P.H.; Kaplan, J.C.

    1976-01-01

    The effect of caffeine on the uv light induction of SV40 virus from two transformed hamster cell lines heterogeneous for the induction of infectious virus was studied. The amount of virus induced was significantly increased in both cell lines when exposure to uv light was followed by treatment with caffeine. Caffeine in the absence of uv irradiation did not stimulate virus induction, nor did it stimulate SV40 replication in a lytic infection. There was an apparent difference in the concentrations of caffeine which maximally stimulated SV40 virus induction in the two cell lines. This effect could not be explained by differences in cell survival after exposure to uv light and caffeine. Since caffeine is known to cause the accumulation of gaps formed in DNA during postreplication repair of uv-irradiated rodent cells, our results support the hypothesis that the formation of gaps or breaks in DNA is an important early step in virus induction

  14. Learned Avoidance in the Male Syrian Hamster: Investigating the Outcome of a Glucocorticoid Antagonist on Reconsolidation

    Directory of Open Access Journals (Sweden)

    Erik Haugsnes

    2015-02-01

    Full Text Available In this experiment, we used our Conflict Alleyway Apparatus and a glucocorticoid antagonist, mifepristone, to investigate the role of glucocorticoids in the reconsolidation of learned avoidance in defeated male Syrian hamsters. Subjects were tested for memory deficits 48 hours and 96 hours after the drug/vehicle was administered. It were hypothesized that mifepristone administration would produce memory deficits when the defeat memory had been reactivated, and that this deficit would be present 48 hours and 96 hours after the administration. Prolonged deficits that are dependent upon memory reactivation would suggest that glucocorticoids play a role in reconsolidation of learned avoidance. Our results indicated a strong evidence for learned avoidance after defeat; however, we did not find any significant drug effect.

  15. Adriamycin resistance, heat resistance and radiation response in Chinese hamster fibroblasts

    International Nuclear Information System (INIS)

    Wallner, K.; Li, G.

    1985-01-01

    Previous investigators have demonstrated synergistic interaction between hyperthermia and radiation or Adriamycin (ADR), using cell lines that are sensitive to heat or ADR alone. The authors investigated the effect of heat, radiation or ADR on Chinese hamster fibroblasts (HA-1), their heat resistant variants and their ADR resistant variants. Heat for ADR resistance did not confer cross resistance to radiation. Cells resistant to heat did show cross resistance to ADR. While cells selected for ADR resistance were not cross resistant to heat, they did not exhibit drug potentiation by hyperthermia, characteristic of ADR sensitive cells. Cytofluorometric measurement showed decreased ADR uptake in both heat and ADR resistant cells. The possibility of cross resistance between heat and ADR should be considered when designing combined modality trials

  16. Glycoengineering of Chinese hamster ovary cells for enhanced erythropoietin N-glycan branching and sialylation

    DEFF Research Database (Denmark)

    Yin, Bojiao; Gao, Yuan; Chung, Cheng-yu

    2015-01-01

    -glycosylation of recombinant erythropoietin (rEPO), a human α2,6-sialyltransferase (ST6Gal1) was expressed in Chinese hamster ovary (CHO-K1) cells. Sialylation increased on both EPO and CHO cellular proteins as observed by SNA lectin analysis, and HPLC profiling revealed that the sialic acid content of total glycans on EPO......EPO from these engineered cells was increased ∼45% higher with tetra-sialylation accounting for ∼10% of total sugar chains compared to ∼3% for the wild-type parental CHO-K1. In this way, coordinated overexpression of these three glycosyltransferases for the first time in model CHO-K1 cell lines provides...

  17. Isolation of hypoxanthine phosphoribosyltransferase-defective mutants in Chinese hamster V79 cells by tritium suicide

    International Nuclear Information System (INIS)

    Bryant, R.E.; Schauer, I.E.; Hatcher, D.G.

    1981-01-01

    Tritium suicide was shown to be a highly efficient method for isolating mutants defective in hypoxanthine incorporation in the Chinese hamster lung of one kill cycle were used for the next kill cycle. The kill cycles involved incorporation of ( 3 H) hypoxanthine for 5 or 10 min, followed by storage of 3 H-labelled cells at -70 0 C for 4-10 days. 12 clones that survived the 3rd kill cycle were tested for incorporation of ( 3 H)hypoxanthine and all were found to be defective. At least 6 of the clones have defective hypoxanthine phosphoribosyltransferase (HPRT) activity. One mutant, H19, chosen for further characterization, had HPRT with a 13-fold elevation in apparent Ksub(m) for phosphoribosylpyrophosphate (PRPP). Thin-layer chromatography of cell extracts showed that this mutant was incapable of converting intracellular hypoxanthine to IMP or to other purine metabolites. In addition, H19 was resistant to 6-thioguanine. (orig.)

  18. Effects of x rays on DNA synthesis in synchronized Chinese hamster ovary cells

    International Nuclear Information System (INIS)

    Laughlin, T.J.; Taylor, J.H.

    1980-01-01

    Chinese hamster ovary cells were synchronized at the beginning of S phase with 5-fluorodeoxyuridine and irradiated with moderte levels ( 3 H]thymidine at various times after irradiation. The cells were lysed immediately after termination of the pulse, and the rate of DNA synthesis, size of the nascent strands, and number of active replicons were determined. The level of DNA synthesis in cells pulse-labeled immediately after x irradiation with 1000 rad was suppressed 20 to 25% but returned to control levels within 4 h after irradiation. Our data demonstrate that this x-ray-induced suppression of DNA synthesis was due entirely to a reduction in the number of active replicons, with no appreciable change in the rate of chain growth

  19. Culture conditions affecting the survival response of Chinese hamster ovary cells treated by hyperthermia

    International Nuclear Information System (INIS)

    Highfield, D.P.; Holahan, E.V.; Dewey, W.C.

    1982-01-01

    Using lethally irradiated feeder cells to control cell population densities, researchers investigated the survival of Chinese hamster ovary cells heated between 42.2 and 45.5 degrees C. Test cells were plated into T25 flasks with or without feeder cells, incubated 2 hours at 37 degrees C, and then given various heat treatments. Under all heating conditions, survival increased in those flasks containing feeder cells. Increased survival (by as much as a factor of 100 for cells heated at 42.4 degrees C for 6-10 hr) was most apparent when cells were heated to thermotolerance. By adjustment of test and feeder cell numbers, survival increased as density increased; however, maximum survival followed a transition period that occurred between the plating of 1 X 10(4) and 6 X 10(4) cells. Experimental artifacts due to improper control of cell density was demonstrated

  20. Mutation of Chinese hamster cells by near-UV activation of promutagens

    International Nuclear Information System (INIS)

    Barnhart, B.J.; Cox, S.H.

    1980-01-01

    A tissue-culture assay for mutagenesis and cytotoxicity incorporating near ultraviolet (NUV) light activation of polyaromatic hydrocarbons (PAH) has been developed. Cultures of Chinese hamster cells (line CHO) growing in suspension culture were inoculated with benzo[a]pyrene (B[a]P), 7,12-dimethylbenzanthracene (DMBA) or shale-oil retort-water and exposed to light from a high-pressure mercury lamp fitted with a Corning NUV bandpass filter. This light source both permitted activation of PAH and the shale-oil water and precluded detectable damage to DNA. Neither the PAH nor the NUV alone had any effect on cell survival or mutation frequencies but the chemicals plus NUV were extremely effective in producing mutations to 6-thioguanine resistance (hgprt gene). (orig.)

  1. Analysis of Chinese hamster ovary cell metabolism through a combined computational and experimental approach.

    Science.gov (United States)

    Chen, Ning; Bennett, Mark H; Kontoravdi, Cleo

    2014-12-01

    Optimization of cell culture processes can benefit from the systematic analysis of experimental data and their organization in mathematical models, which can be used to decipher the effect of individual process variables on multiple outputs of interest. Towards this goal, a kinetic model of cytosolic glucose metabolism coupled with a population-level model of Chinese hamster ovary cells was used to analyse metabolic behavior under batch and fed-batch cell culture conditions. The model was parameterized using experimental data for cell growth dynamics, extracellular and intracellular metabolite profiles. The results highlight significant differences between the two culture conditions in terms of metabolic efficiency and motivate the exploration of lactate as a secondary carbon source. Finally, the application of global sensitivity analysis to the model parameters highlights the need for additional experimental information on cell cycle distribution to complement metabolomic analyses with a view to parameterize kinetic models.

  2. Cloning and Expression of Luteinizing Hormone Subunits in Chinese Hamster Ovary Cell Line

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    Zeinab Soleimanifar

    2016-10-01

    Full Text Available Background: Luteinizing hormone (LH was secreted by the stimulating cells of the testes and ovaries in the anterior pituitary gland. The application of this hormone is in the treatment of men and women with infertility and amenorrhea respectively.Materials and Methods: In the present study the alpha and beta subunits of human LH gene were cloned into the pEGFP-N1 expression vector and produced the recombinant LH hormone in Chinese hamster ovary (CHO eukaryotic system.Results: Alpha and beta subunits of LH hormone were cloned between NheI and BamHI cut sites of pEGFP_N1 expression plasmid and confirmed by PCR.  Hormone expression was evaluated in CHO cell line by Western blotting using the specific antibody.Conclusion: Alpha and beta subunits of LH hormone were expressed in CHO cell line perfectly.

  3. UV-induced chromatid aberrations in two cell linear of Chinese hamster with different repair activity

    International Nuclear Information System (INIS)

    Ikushima, Takaji

    1978-01-01

    To elucidate the mechanism of chromosomal aberration formation, the yield and type of chromosomal aberrations induced by ultraviolet light (UV) irradiation were compared in cultured Chinese hamster cells with different repair activity. After irradiation of low fluences of UV, chromatid aberrations were produced more frequently in one cell line with impaired repair activity, B14FAF than the other showing normal DNA repair replication, CHO. There were no difference in the spectrum of the aberration types between the two. The results imply that impaired excision repair of UV-induced pyrimidine dimers or other photoproducts results in higher yield of chromosomal aberrations, and suggest the involvement of DNA repair processes in chromosomal aberration formation. (author)

  4. Unique biophysical studies with diatomic deuterium beams. [Survival studies with V79 Chinese hamster cells

    Energy Technology Data Exchange (ETDEWEB)

    Rohrig, N.; Bird, R.P.; Colvett, R.D.; Rossi, H.H.; Marino, S.A.

    1978-01-01

    By irradiating cells attached to thin Mylar foils with diatomic deuteron beams, the role of interaction distance in radiobiology can be investigated in a unique manner. The molecule breaks up into two separate ions which diverge from each other because of the multiple scattering process in the foil and in the cellular material. A distribution of separation distances results whose characteristic separation depends on the Mylar foil thickness. An experimental facility to use diatomic beams is described. Cell survival results for V79 Chinese hamster cells synchronized in late S phase show that damage does result from tracks separated by as much as 250 nm. However, damage also results from interaction at nanometer dimensions.

  5. Picomolar-affinity binding and inhibition of adenylate cyclase activity by melatonin in Syrian hamster hypothalamus

    International Nuclear Information System (INIS)

    Niles, L.P.; Hashemi, F.

    1990-01-01

    1. The effect of melatonin on forskolin-stimulated adenylate cyclase activity was measured in homogenates of Syrian hamster hypothalamus. In addition, the saturation binding characteristics of the melatonin receptor ligand, [ 125 I]iodomelatonin, was examined using an incubation temperature (30 degree C) similar to that used in enzyme assays. 2. At concentrations ranging from 10 pM to 1 nM, melatonin caused a significant decrease in stimulated adenylate cyclase activity with a maximum inhibition of approximately 22%. 3. Binding experiments utilizing [ 125 I]iodomelatonin in a range of approximately 5-80 pM indicated a single class of high-affinity sites: Kd = 55 +/- 9 pM, Bmax = 1.1 +/- 0.3 fmol/mg protein. 4. The ability of picomolar concentrations of melatonin to inhibit forskolin-stimulated adenylate cyclase activity suggests that this affect is mediated by picomolar-affinity receptor binding sites for this hormone in the hypothalamus

  6. Humoral response of paracoccidioidomycosis sera in hamsters with different Venezuelan isolates

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    Lilian M Spencer

    2009-09-01

    Full Text Available Humoral response of paracoccidioidomycosis sera in hamsters with different Venezuelan isolates. Paracoccidioidomycosis (PCM is a progressive systemic mycosis caused by the fungus Paraccocidioides brasiliensis (Pb, endemic to Venezuela and Latin America. In this study, eight different Venezuelan isolates obtained from patients with PCM, were inoculated intraperitoneally in Syrian hamsters (Cricetus auratus and studied by immune-serum. Each strain was collected by gently scraping the surface of the culture medium (Sabouraud Dextrose Agar and suspended in 3ml of 0.15 M phosphate-buffered saline. The antigen obtained was called Paraccocidioides brasiliensis Crude Antigen (CAP. Immunoblotting results showed that the immune-sera from hamsters recognized at least 3 bands: one over 200 kDa, and two of 80 and 15-20 kDa. This study suggests that IgG anti-CAP can reveal a significant variability in the eight Venezuelan isolates. Sera from 88 infected hamsters were evaluated by ELISA with eight different CAPs and Western blot with CAP 37383. ELISA results showed that, the antigen of the virulent isolate 37383 had the highest percentage (38% of positivity, while the non-virulent isolate 1458 had the lowest one (13.6%. Furthermore, scanning densitometry revealed that the isolate 37383 had less bands than the non-virulent isolates. These results suggest that the ELISA test with CAP 37383 can detect circulating antibodies, and that this virulent isolate may be useful for the diagnosis of PCM, and to monitor disease responses to treatments. Rev. Biol. Trop. 57 (3: 505-513. Epub 2009 September 30.La Paracoccidioidomicosis (PCM, es una micosis sistémica causada por el hongo Paraccocidioides brasiliensis (Pb, endémica en Venezuela y Latino América. En este estudio ocho diferentes aislados venezolanos, obtenidos de pacientes con PCM, fueron inoculados intraperitonealmente en hámsteres y fueron estudiados por ELISA e inmunoblotting. Los antígenos obtenidos de P

  7. Dietary Plant Sterol Esters Must Be Hydrolyzed to Reduce Intestinal Cholesterol Absorption in Hamsters.

    Science.gov (United States)

    Carden, Trevor J; Hang, Jiliang; Dussault, Patrick H; Carr, Timothy P

    2015-07-01

    Elevated concentrations of LDL cholesterol are associated with the development of atherosclerosis and therefore are considered an important target for intervention to prevent cardiovascular diseases. The inhibition of cholesterol absorption in the small intestine is an attractive approach to lowering plasma cholesterol, one that is addressed by drug therapy as well as dietary supplementation with plant sterols and plant sterol esters (PSEs). This study was conducted to test the hypothesis that the cholesterol-lowering effects of PSE require hydrolysis to free sterols (FSs). Male Syrian hamsters were fed atherogenic diets (AIN-93M purified diet containing 0.12% cholesterol and 8% coconut oil) to which one of the following was added: no PSEs or ethers (control), 5% sterol stearate esters, 5% sterol palmitate esters (PEs), 5% sterol oleate esters (OEs), 5% sterol stearate ethers (STs; to mimic nonhydrolyzable PSE), or 3% FSs plus 2% sunflower oil. The treatments effectively created a spectrum of PSE hydrolysis across which cholesterol metabolism could be compared. Metabolic measurements included cholesterol absorption, plasma and liver lipid concentration, and fecal neutral sterol and bile acid excretion. The STs and the PEs and SEs were poorly hydrolyzed (1.69-4.12%). In contrast, OEs were 88.3% hydrolyzed. The percent hydrolysis was negatively correlated with cholesterol absorption (r = -0.85; P cholesterol excretion (r = 0.92; P cholesterol-lowering properties of PSE. Our data on hamsters suggest that PSE hydrolysis and the presence of FSs is necessary to induce an optimum cholesterol-lowering effect and that poorly hydrolyzed PSEs may lower cholesterol through an alternative mechanism than that of competition with cholesterol for micelle incorporation. © 2015 American Society for Nutrition.

  8. Dietary Plant Sterol Esters Must Be Hydrolyzed to Reduce Intestinal Cholesterol Absorption in Hamsters123

    Science.gov (United States)

    Carden, Trevor J; Hang, Jiliang; Dussault, Patrick H; Carr, Timothy P

    2015-01-01

    Background: Elevated concentrations of LDL cholesterol are associated with the development of atherosclerosis and therefore are considered an important target for intervention to prevent cardiovascular diseases. The inhibition of cholesterol absorption in the small intestine is an attractive approach to lowering plasma cholesterol, one that is addressed by drug therapy as well as dietary supplementation with plant sterols and plant sterol esters (PSEs). Objective: This study was conducted to test the hypothesis that the cholesterol-lowering effects of PSE require hydrolysis to free sterols (FSs). Methods: Male Syrian hamsters were fed atherogenic diets (AIN-93M purified diet containing 0.12% cholesterol and 8% coconut oil) to which one of the following was added: no PSEs or ethers (control), 5% sterol stearate esters, 5% sterol palmitate esters (PEs), 5% sterol oleate esters (OEs), 5% sterol stearate ethers (STs; to mimic nonhydrolyzable PSE), or 3% FSs plus 2% sunflower oil. The treatments effectively created a spectrum of PSE hydrolysis across which cholesterol metabolism could be compared. Metabolic measurements included cholesterol absorption, plasma and liver lipid concentration, and fecal neutral sterol and bile acid excretion. Results: The STs and the PEs and SEs were poorly hydrolyzed (1.69–4.12%). In contrast, OEs were 88.3% hydrolyzed. The percent hydrolysis was negatively correlated with cholesterol absorption (r = −0.85; P cholesterol excretion (r = 0.92; P cholesterol-lowering properties of PSE. Conclusions: Our data on hamsters suggest that PSE hydrolysis and the presence of FSs is necessary to induce an optimum cholesterol-lowering effect and that poorly hydrolyzed PSEs may lower cholesterol through an alternative mechanism than that of competition with cholesterol for micelle incorporation. PMID:25972524

  9. Vimentin and laminin are altered on cheek pouch microvessels of streptozotocin-induced diabetic hamsters

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    Jemima Fuentes R Silva

    2011-01-01

    Full Text Available OBJECTIVE: Normal endothelial cells respond to shear stress by elongating and aligning in the direction of fluid flow. Hyperglycemia impairs this response and contributes to microvascular complications, which result in deleterious effects to the endothelium. This work aimed to evaluate cheek pouch microvessel morphological characteristics, reactivity, permeability, and expression of cytoskeleton and extracellular matrix components in hamsters after the induction of diabetes with streptozotocin. METHODS: Syrian golden hamsters (90-130 g were injected with streptozotocin (50 mg/kg, i.p. or vehicle either 6 (the diabetes mellitus 6 group or 15 (the diabetes mellitus 15 group days before the experiment. Vascular dimensions and density per area of vessels were determined by morphometric and stereological measurements. Changes in blood flow were measured in response to acetylcholine, and plasma extravasation was measured by the number of leakage sites. Actin, talin, α-smooth muscle actin, vimentin, type IV collagen, and laminin were detected by immunohistochemistry and assessed through a semiquantitative scoring system. RESULTS: There were no major alterations in the lumen, wall diameters, or densities of the examined vessels. Likewise, vascular reactivity and permeability were not altered by diabetes. The arterioles demonstrated increased immunoreactivity to vimentin and laminin in the diabetes mellitus 6 and diabetes mellitus 15 groups. DISCUSSION: Antibodies against laminin and vimentin inhibit branching morphogenesis in vitro. Therefore, laminin and vimentin participating in the structure of the focal adhesion may play a role in angiogenesis. CONCLUSIONS: Our results indicated the existence of changes related to cell-matrix interactions, which may contribute to the pathological remodeling that was already underway one week after induction of experimental diabetes.

  10. Identifying Early Target Cells of Nipah Virus Infection in Syrian Hamsters.

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    Laura Baseler

    2016-11-01

    Full Text Available Nipah virus causes respiratory and neurologic disease with case fatality rates up to 100% in individual outbreaks. End stage lesions have been described in the respiratory and nervous systems, vasculature and often lymphoid organs in fatal human cases; however, the initial target organs of Nipah virus infection have not been identified. Here, we detected the initial target tissues and cells of Nipah virus and tracked virus dissemination during the early phase of infection in Syrian hamsters inoculated with a Nipah virus isolate from Malaysia (NiV-M or Bangladesh (NiV-B.Syrian hamsters were euthanized between 4 and 48 hours post intranasal inoculation and tissues were collected and analyzed for the presence of viral RNA, viral antigen and infectious virus. Virus replication was first detected at 8 hours post inoculation (hpi. Nipah virus initially targeted type I pneumocytes, bronchiolar respiratory epithelium and alveolar macrophages in the lung and respiratory and olfactory epithelium lining the nasal turbinates. By 16 hpi, virus disseminated to epithelial cells lining the larynx and trachea. Although the pattern of viral dissemination was similar for both virus isolates, the rate of spread was slower for NiV-B. Infectious virus was not detected in the nervous system or blood and widespread vascular infection and lesions within lymphoid organs were not observed, even at 48 hpi.Nipah virus initially targets the respiratory system. Virus replication in the brain and infection of blood vessels in non-respiratory tissues does not occur during the early phase of infection. However, virus replicates early in olfactory epithelium and may serve as the first step towards nervous system dissemination, suggesting that development of vaccines that block virus dissemination or treatments that can access the brain and spinal cord and directly inhibit virus replication may be necessary for preventing central nervous system pathology.

  11. Identifying Early Target Cells of Nipah Virus Infection in Syrian Hamsters.

    Science.gov (United States)

    Baseler, Laura; Scott, Dana P; Saturday, Greg; Horne, Eva; Rosenke, Rebecca; Thomas, Tina; Meade-White, Kimberly; Haddock, Elaine; Feldmann, Heinz; de Wit, Emmie

    2016-11-01

    Nipah virus causes respiratory and neurologic disease with case fatality rates up to 100% in individual outbreaks. End stage lesions have been described in the respiratory and nervous systems, vasculature and often lymphoid organs in fatal human cases; however, the initial target organs of Nipah virus infection have not been identified. Here, we detected the initial target tissues and cells of Nipah virus and tracked virus dissemination during the early phase of infection in Syrian hamsters inoculated with a Nipah virus isolate from Malaysia (NiV-M) or Bangladesh (NiV-B). Syrian hamsters were euthanized between 4 and 48 hours post intranasal inoculation and tissues were collected and analyzed for the presence of viral RNA, viral antigen and infectious virus. Virus replication was first detected at 8 hours post inoculation (hpi). Nipah virus initially targeted type I pneumocytes, bronchiolar respiratory epithelium and alveolar macrophages in the lung and respiratory and olfactory epithelium lining the nasal turbinates. By 16 hpi, virus disseminated to epithelial cells lining the larynx and trachea. Although the pattern of viral dissemination was similar for both virus isolates, the rate of spread was slower for NiV-B. Infectious virus was not detected in the nervous system or blood and widespread vascular infection and lesions within lymphoid organs were not observed, even at 48 hpi. Nipah virus initially targets the respiratory system. Virus replication in the brain and infection of blood vessels in non-respiratory tissues does not occur during the early phase of infection. However, virus replicates early in olfactory epithelium and may serve as the first step towards nervous system dissemination, suggesting that development of vaccines that block virus dissemination or treatments that can access the brain and spinal cord and directly inhibit virus replication may be necessary for preventing central nervous system pathology.

  12. Cyclophosphamide enhances antitumor efficacy of oncolytic adenovirus expressing uracil phosphoribosyltransferase (UPRT) in immunocompetent Syrian hamsters.

    Science.gov (United States)

    Hasegawa, Naoyuki; Abei, Masato; Yokoyama, Kazunari K; Fukuda, Kuniaki; Seo, Emiko; Kawashima, Rei; Nakano, Yuri; Yamada, Takeshi; Nakade, Koji; Hamada, Hirofumi; Obata, Yuichi; Hyodo, Ichinosuke

    2013-09-15

    Oncolytic viruses (OVs) are novel cancer therapeutics with great promise, but host antiviral immunity represents the hurdle for their efficacy. Immunosuppression by cyclophosphamide (CP) has thus been shown to enhance the oncolytic efficacy of many OVs, but its effects on OVs armed with therapeutic genes remain unknown. We have previously reported on the efficacy of AxE1CAUP, an oncolytic adenovirus (OAd) expressing uracil phosphoribosyltransferase (UPRT), an enzyme that markedly enhanced the toxicity of 5-fluorouracil (5-FU), in immunodeficient, Ad-nonpermissive nude mice. Here we explored the efficacy and safety of intratumoral (i.t.) AxE1CAUP/5-FU therapy and of its combination with CP for syngenic HaP-T1 pancreatic cancers in immunocompetent, Ad-permissive Syrian hamsters. AxE1CAUP infected, replicated, expressed UPRT, and increased the sensitivity to 5-FU in HaP-T1 cells in vitro. I.t. AxE1CAUP/5-FU treatment inhibited the growth of subcutaneous HaP-T1 allografts. The combination with high-dose CP inhibited serum Ad-neutralizing antibody formation, increased intratumoral AxE1CAUP replication and UPRT expression, and resulted in further enhanced therapeutic effects with 5-FU. Neither body weight nor histology of the liver and lung changed during these treatments. A clinically-approved, intermediate-dose CP also enhanced the efficacy of i.t. AxE1CAUP/5-FU treatment in these hamsters, which was not affected by preexisting immunity to the vector. These data demonstrate the excellent antitumor efficacy and safety of an OAd armed with a suicide gene in combination with CP for treating syngenic tumors in immunocompetent, Ad-permissive animals, indicating the efficacy of CP in overcoming the hurdle of antiviral immunity for effective OV-mediated gene therapy. Copyright © 2013 UICC.

  13. Oxotremorine delays and scopolamine accelerates sexual exhaustion when applied to the preoptic area in male hamsters.

    Science.gov (United States)

    Floody, Owen R

    2013-09-01

    Acetylcholine (ACh) has not been tested for a role in the development of sexual exhaustion in males. However, male hamsters receiving infusions into the medial preoptic area (MPOA) of the muscarinic agonist oxotremorine (OXO) or antagonist scopolamine (SCO) show changes in the postejaculatory interval, one of the measures that changes most consistently as exhaustion approaches. In addition, central SCO treatments cause changes in the patterning of intromissions that resemble those signaling exhaustion. To extend these observations and more thoroughly test the dependence of sexual exhaustion on ACh, male hamsters received MPOA treatments of OXO, SCO or the combination of the two before mating to exhaustion. Relative to placebo, OXO infusions caused small but consistent increases in ejaculation frequency and long intromission latency, delaying the appearance of exhaustion. Scopolamine treatments did the reverse, dramatically accelerating the development of exhaustion. Consistent with and possibly responsible for these changes were effects on the quality of performance prior to exhaustion. These included differences in overall copulatory efficiency (e.g., ejaculations/intromission), which was increased by OXO and decreased by SCO. They also extended to several standard measures of copulatory behavior, including intromission frequency, ejaculation latency and the postejaculatory interval: Most of these were increased by SCO and decreased by OXO. Finally, whereas most or all effects of OXO were counteracted by SCO, most or all of the responses to SCO resisted change by added OXO. This asymmetry in the responses to combined treatment raises the possibility that the effects of these drugs on sexual exhaustion and other elements of male behavior are mediated by distinct muscarinic receptors. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Pathogenesis and host response in Syrian hamsters following intranasal infection with Andes virus.

    Directory of Open Access Journals (Sweden)

    David Safronetz

    2011-12-01

    Full Text Available Hantavirus pulmonary syndrome (HPS, also referred to as hantavirus cardiopulmonary syndrome (HCPS, is a rare but frequently fatal disease caused by New World hantaviruses. In humans HPS is associated with severe pulmonary edema and cardiogenic shock; however, the pathogenesis of this disease remains unclear largely due to a lack of suitable animal models for the study of disease progression. In this study we monitored clinical, virological, pathophysiological parameters and host immunological responses to decipher pathological factors and events in the lethal Syrian hamster model of HPS following intranasal inoculation of Andes virus. Transcriptional profiling of the host gene responses demonstrated a suppression of innate immune responses in most organs analyzed during the early stage of infection, except for in the lung which had low level activation of several pro-inflammatory genes. During this phase Andes virus established a systemic infection in hamsters, with viral antigen readily detectable in the endothelium of the majority of tissues analyzed by 7-8 days post-inoculation. Despite wide-spread infection, histological analysis confirmed pathological abnormalities were almost exclusively found in the lungs. Immediately preceding clinical signs of disease, intense activation of pro-inflammatory and Th1/Th2 responses were observed in the lungs as well as the heart, but not in peripheral organs, suggesting that localized immune-modulations by infection is paramount to pathogenesis. Throughout the course of infection a strong suppression of regulatory T-cell responses was noted and is hypothesized to be the basis of the aberrant immune activations. The unique and comprehensive monitoring of host immune responses to hantavirus infection increases our understanding of the immuno-pathogenesis of HPS and will facilitate the development of treatment strategies targeting deleterious host immunological responses.

  15. Amygdalar glutamatergic neuronal systems play a key role on the hibernating state of hamsters

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    Facciolo Rosa

    2011-01-01

    Full Text Available Abstract Background Excitatory transmitting mechanisms are proving to play a critical role on neuronal homeostasis conditions of facultative hibernators such as the Syrian golden hamster. Indeed works have shown that the glutamatergic system of the main olfactory brain station (amygdala is capable of controlling thermoregulatory responses, which are considered vital for the different hibernating states. In the present study the role of amygdalar glutamatergic circuits on non-hibernating (NHIB and hibernating (HIB hamsters were assessed on drinking stimuli and subsequently compared to expression variations of some glutamatergic subtype mRNA levels in limbic areas. For this study the two major glutamatergic antagonists and namely that of N-methyl-D-aspartate receptor (NMDAR, 3-(+-2-carboxypiperazin-4-yl-propyl-1-phosphonate (CPP plus that of the acid α-amine-3-hydroxy-5-metil-4-isoxazol-propionic receptor (AMPAR site, cyano-7-nitro-quinoxaline-2,3-dione (CNQX were infused into the basolateral amygdala nucleus. Attempts were made to establish the type of effects evoked by amygdalar glutamatergic cross-talking processes during drinking stimuli, a response that may corroborate their major role at least during some stages of this physiological activity in hibernators. Results From the behavioral results it appears that the two glutamatergic compounds exerted distinct effects. In the first case local infusion of basolateral complexes (BLA with NMDAR antagonist caused very great (p Conclusion We conclude that predominant drinking events evoked by glutamatergic mechanisms, in the presence of prevalently down regulated levels of NR1/2A of some telencephalic and hypothalamic areas appear to constitute an important neuronal switch at least during arousal stage of hibernation. The establishment of the type of glutamatergic subtypes that are linked to successful hibernating states, via drinking stimuli, may have useful bearings toward sleeping disorders.

  16. Increase of monoamine oxidase-B activity in the brain of scrapie-infected hamsters.

    Science.gov (United States)

    Adjou, Karim Tarik; Dilda, Pierre; Aumond, Pascal; Gueddari, Salah; Deslys, Jean-Philippe; Dormont, Dominique; Seman, Michel

    2008-06-01

    In the present study, the purpose is to determine activities of monoamine oxidases (MAO) in the brain of 263K scrapie-infected hamsters during the development of this experimental prion disease. Indeed, MAO activity modifications which have already been related in aging and neurodegenerations is suspected to be involved in the neuron loss process by elevated hydrogen peroxide formation. Monoamine oxidase type A (MAO-A) and B (MAO-B) activities were followed in the brain at different stages of the disease. MAO-A activity did not change significantly during the evolution of the disease. However, concerning the MAO-B activity, a significant increase was observed from 50 days post-infection and through the course of the disease and reached 42.9+/-5.3% at its ultimate stage. Regarding these results, MAO-B could be a potential therapeutic target then we have performed a pre-clinical treatment with irreversible (Selegiline or L-deprenyl) or and reversible (MS-9510) MAO-B inhibitors used alone or in association with an anti-scrapie drug such as MS-8209, an amphotericin B derivative. Our results show that none of the MAO-B inhibitors used was able to delay the onset of the disease. Neither these MAO-B inhibitors nor R-NMDA inhibitors (MK-801) can enhance the effects of MS-8209. The present findings clearly indicate a significant increase of cerebral MAO-B activity in scrapie-infected hamsters. Furthermore, inhibitors of MAO-B do not have any curative or palliative effect on this experimental model indicating that the raise of this activity is probably more a consequence rather than a causal event of the neurodegenerative process.

  17. Dim light at night disrupts the short-day response in Siberian hamsters.

    Science.gov (United States)

    Ikeno, Tomoko; Weil, Zachary M; Nelson, Randy J

    2014-02-01

    Photoperiodic regulation of physiology, morphology, and behavior is crucial for many animals to survive seasonally variable conditions unfavorable for reproduction and survival. The photoperiodic response in mammals is mediated by nocturnal secretion of melatonin under the control of a circadian clock. However, artificial light at night caused by recent urbanization may disrupt the circadian clock, as well as the photoperiodic response by blunting melatonin secretion. Here we examined the effect of dim light at night (dLAN) (5lux of light during the dark phase) on locomotor activity rhythms and short-day regulation of reproduction, body mass, pelage properties, and immune responses of male Siberian hamsters. Short-day animals reduced gonadal and body mass, decreased spermatid nuclei and sperm numbers, molted to a whiter pelage, and increased pelage density compared to long-day animals. However, animals that experienced short days with dLAN did not show these short-day responses. Moreover, short-day specific immune responses were altered in dLAN conditions. The nocturnal activity pattern was blunted in dLAN hamsters, consistent with the observation that dLAN changed expression of the circadian clock gene, Period1. In addition, we demonstrated that expression levels of genes implicated in the photoperiodic response, Mel-1a melatonin receptor, Eyes absent 3, thyroid stimulating hormone receptor, gonadotropin-releasing hormone, and gonadotropin-inhibitory hormone, were higher in dLAN animals than those in short-day animals. These results suggest that dLAN disturbs the circadian clock function and affects the molecular mechanisms of the photoperiodic response. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Sex differences in motivational responses to dietary fat in Syrian hamsters.

    Science.gov (United States)

    Shannonhouse, John L; Grater, Danielle M; York, Daniel; Wellman, Paul J; Morgan, Caurnel

    2015-08-01

    Women are more likely than men to exhibit motivational disorders (e.g., anhedonia and anxiety) with limited treatment options, and to overconsume high-fat "comfort foods" to improve motivational disruptions. Unfortunately, neurobiological underpinnings for sex differences in motivational disruptions and their responses to dietary fat are poorly understood. To help bridge these fundamental knowledge gaps, we assessed behavioral and neurobiological responses to dietary fat in a hamster model of female-biased motivational lability. Relative to social housing, social separation reduced hedonic drive in a new behavioral assay, the reward investigational preference (RIP) test. Fluoxetine or desipramine treatment for 21, but not 7, days improved RIP test performance. Pharmacologic specificity in this test was shown by non-responsiveness to diazepam, tracazolate, propranolol, or naltrexone. In the anxiety-related feeding/exploration conflict (AFEC) test, social separation worsened latency to eat highly palatable food under anxiogenic conditions, but not in home cages. Social separation also reduced weight gain, food intake, and adiposity while elevating energy expenditure, assessed by caloric efficiency and indirect calorimetry. Furthermore, chronic high-fat feeding improved anhedonic and anxious responses to separation, particularly in females. In the motivation-influencing nucleus accumbens, females, but not males, exhibited a separation-induced anxiety-related decrease in Creb1 mRNA levels and an anhedonia-related decrease in ΔFosb mRNA levels. Consistent with its antidepressant- and anxiolytic-like effects on behavior, high-fat feeding elevated accumbal Creb1 and ΔFosb mRNA levels in females only. Another accumbal reward marker, Tlr4 mRNA, was elevated in females by high-fat feeding. These results show that social separation of hamsters provides a novel model of sex-dependent comorbid anhedonia, anxiety, and anorexia, and implicate accumbal CREB, ΔFosB, and TLR4

  19. Effects of fish oil and spirulina on oxidative stress and inflammation in hypercholesterolemic hamsters.

    Science.gov (United States)

    Muga, Miriam Adoyo; Chao, Jane C-J

    2014-12-06

    Altered plasma lipids, oxidative stress, and inflammation have been involved in the pathogenesis of cardiovascular disease. Fish oil has shown inconclusive effects on plasma lipids and oxidative stress. Spirulina has both cholesterol lowering and antioxidant properties. However, the effect of fish oil and spirulina on hypercholesterolemia has not been studied. We investigated the effects of fish oil, spirulina, and their combination on hypercholesterolemia. The hamsters were divided into 7 groups: control, high cholesterol (HF), fish oil (post FO), spirulina (post SP), and a combination of fish oil and spirulina (post SF, pre-SF, and HF + SF) groups. The HF and HF + SF groups were given a high cholesterol diet for 8 weeks. The post FO, post SP, and post SF groups were given a high cholesterol diet for 4 weeks and then the treatment for 4 weeks. The pre-SF group was given the combined treatment for 4 weeks and then a high cholesterol diet for 4 weeks. The HF and HF + SF groups altered plasma lipids, increased oxidative stress, inhibited antioxidants, and increased inflammation. While the post FO group increased plasma lipids and was more atherogenic. The vice versa was observed in spirulina-treated group. Both the post SP and post SF groups inhibited oxidative stress and increased antioxidant status, and post FO and post SP diets regulated pro-inflammatory cytokines to near the control levels. Both single treatment of fish oil or spirulina inhibit oxidative stress and inflammation. Treatment with a combination of fish oil and spirulina (post SF) may be beneficial for diet-induced hypercholesterolemic hamsters.

  20. Ganciclovir inhibits human adenovirus replication and pathogenicity in permissive immunosuppressed Syrian hamsters.

    Science.gov (United States)

    Ying, Baoling; Tollefson, Ann E; Spencer, Jacqueline F; Balakrishnan, Lata; Dewhurst, Stephen; Capella, Cristina; Buller, R Mark L; Toth, Karoly; Wold, William S M

    2014-12-01

    Adenovirus infections of immunocompromised patients can develop into deadly multiorgan or systemic disease. The virus is especially threatening for pediatric allogeneic hematopoietic stem cell transplant recipients; according to some studies, 10% or more of these patients succumb to disease resulting from adenovirus infection. At present, there is no drug approved for the treatment or prevention of adenovirus infections. Compounds that are approved to treat other virus infections are used off-label to combat adenovirus, but only anecdotal evidence of the efficacy of these drugs exists. Ganciclovir, a drug approved for the treatment of herpesvirus infection, was previously reported to be effective against human adenoviruses in vitro. To model adenovirus infections in immunocompromised humans, we examined ganciclovir's efficacy in immunosuppressed Syrian hamsters intravenously infected with type 5 human adenovirus (Ad5). This animal model is permissive for Ad5 replication, and the animals develop symptoms similar to those seen in humans. We demonstrate that ganciclovir suppresses Ad5 replication in the liver of infected hamsters and that it mitigates the consequences of Ad5 infections in these animals when administered prophylactically or therapeutically. We show that ganciclovir inhibits Ad5 DNA synthesis and late gene expression. The mechanism of action for the drug is not clear; preliminary data suggest that it exerts its antiadenoviral effect by directly inhibiting the adenoviral DNA polymerase. While more extensive studies are required, we believe that ganciclovir is a promising drug candidate to treat adenovirus infections. Brincidofovir, a drug with proven activity against Ad5, was used as a positive control in the prophylactic experiment. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  1. Pharmacokinetics and tissue distribution of Antimony after multiple intramuscular administrations in the Hamster

    International Nuclear Information System (INIS)

    Al-Jaser, May H.; Radwan, Mahasen A.; Zaghloul, Imam Y.

    2006-01-01

    The fate of pentavalent antimony (Sb) in different tissues in the body after intramuscular administration is of great interest for the future study of Sb therapy in different sitting. Pharmacokinetics and tissue distribution of antimony (Sb) were studied in the hamster after daily dose of sodium stibogluconate equivalent to 120 mg kg of Sb, administered intramuscularly for two weeks. Liver, spleen, heart, kidney and skin tissues were isolated after blood collection at the specified time. Antimony was measured in these tissues after suitable treatment, ashing and processing, by flame less atomic absorption spectrophotometry. The concentration of Sb time profile in blood showed a linear raid decline with elimination half life (tz1/2) of 1.7h. The concentration of drug (ug/gm) declined in a biphasic manner from almost all tissues. However, the concentrations of Sb were declined in slower fashion from the hamster tissues than from the blood. The maximum concentration of Sb was determined in the kidney tissues (3416+-631ug/gm) while the lowest concentration was in the spleen (209+-187ug/gm). The maximum concentration of Sb in the kidney (ug/gm) was more than 25 fold higher than that measured from blood (ug/ml). The AUC of Sb in the studied tissues was in this rank: kidney>liver>skin>spleen>heart>blood. Surprisingly, the heart, spleen and liver showed a similar t1/2 of 5.2-6.2h while the kidney and skin had a t1/2 of about 3h. Therefore, disposition of Sb seems to kinetically follow multicompartmental compartmental model. The kidneys got the highest concentration of drug which may lead to nephrotoxicity on long term therapy. (author)

  2. Topical methotrexate pretreatment enhances the therapeutic effect of topical 5-aminolevulinic acid-mediated photodynamic therapy on hamster buccal pouch precancers

    Directory of Open Access Journals (Sweden)

    Deng-Fu Yang

    2014-09-01

    Conclusion: We conclude that topical MTX-pretreatment can increase intracellular PpIX production in hamster buccal pouch precancerous lesions and significantly improves the outcomes of the precancerous lesions treated with topical ALA-PDT.

  3. Short-term study of the uptake of PrPSc by the Peyer’s patches in hamsters after oral exposure to scrapie

    DEFF Research Database (Denmark)

    Bergström, Ann-Louise; Jensen, Tim Kåre; Heegaard, Peter M. H.

    2006-01-01

    The disease-associated prion protein (PrPSc) has been detected in the ileal Peyer's patches of lambs as early as one week after oral exposure to scrapie. In hamsters, the earliest reported time of PrPSc detection in the Peyer's patches after oral exposure to scrapie is 69 days post-infection. To ......The disease-associated prion protein (PrPSc) has been detected in the ileal Peyer's patches of lambs as early as one week after oral exposure to scrapie. In hamsters, the earliest reported time of PrPSc detection in the Peyer's patches after oral exposure to scrapie is 69 days post......-infection. To evaluate the acute uptake of inoculum and to investigate whether the Peyer's patches constitute the primary site of entry for scrapie after oral exposure, hamsters were each exposed orally to 1 ml of a 10% brain homogenate from hamsters in the terminal stage of infection with the 263 K strain...

  4. A study of the low level radiation effect on the mitotic index of the basal cells in the buccal pouch of hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Byung Cheol; You, Dong Soo [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    1993-08-15

    The purpose of this study was to investigate the defects of the low level irradiation on the mitotic index of the basal cells in the buccal pouch of hamsters (golden hamster: APG strain). After colchicine was administrated to the hamsters through the intraperitoneal, the low level radiation (5461 mR) was exposed in the buccal pouch of hamsters. The mitotic index of the basal cells was estimated 2 hours after irradiation. The results were as follows: 1. The mean mitotic index of the control group was 4.32. 2. The mean mitotic index of the irradiated group was 2.46. 3. T-test of data in the irradiated group showed significant difference from the mitotic endex in the control group. These results suggested the lowered mitotic index of the irradiated group resulted from the low level irradiation.

  5. Study of the combined effects of smoking and inhalation of uranium ore dust, radon daughters and diesel oil exhaust fumes in hamsters and dogs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cross, F.T.; Palmer, R.F.; Filipy, R.E.; Busch, R.H.; Stuart, B.O.

    1978-09-01

    Exposure to particulates from uranium ore dust and diesel exhaust soot provoked inflammatory and proliferative responses in lungs. Also exposure to radon and radon daughters yielded increased occurrences of bronchiolar epithelial hyperplasia and metaplastic changes of alveolar epithelium. The data suggest that this cellular change is also a precursor of premalignant change in hamsters. The authors suggest an animal model other than the hamster based on two observations: (1) the Syrian golden hamster has been shown to be highly refractory to carcinoma induction; and (2) that when exposed to realistic levels of agents in life-span exposure regimens, the hamster does not develop lesions. Dog studies with cigarette smoke exposure showed mitigating effects on radon daughter induced respiratory tract cancer. Two reasons are suggested although no empirical evidence was gathered. A strict comparison of human and animal exposures and interpolative models are not possible at this time. (PCS)

  6. Bio F1B hamster: a unique animal model with reduced lipoprotein lipase activity to investigate nutrient mediated regulation of lipoprotein metabolism

    Directory of Open Access Journals (Sweden)

    Cornish Marion L

    2007-12-01

    Full Text Available Abstract Background Bio F1B hamster is an inbred hybrid strain that is highly susceptible to diet-induced atherosclerosis. We previously reported that feeding a high fat fish oil diet to Bio F1B hamster caused severe hyperlipidaemia. In this study we compared the effects of various diets in the Bio F1B hamster and the Golden Syrian hamster, which is an outbred hamster strain to investigate whether genetic background plays an important role in dietary fat mediated regulation of lipoprotein metabolism. We further investigated the mechanisms behind diet-induced hyperlipidaemia in F1B hamster. Methods The Bio F1B and Golden Syrian hamsters, 8 weeks old, were fed high fat diets rich in either monounsaturated fatty acids, an n-6: n-3 ratio of 5 or a fish oil diet for 4 weeks. Animals were fasted overnight and blood and tissue samples were collected. Plasma was fractionated into various lipoprotein fractions and assayed for triacylglycerol and cholesterol concentrations. Plasma lipoprotein lipase activity was measured using radioisotope method. Microsomal triglyceride transfer protein activity was measured in the liver and intestine. Plasma apolipoproteinB48, -B100 and apolipoprotein E was measured using Western blots. Two-way ANOVA was used to determine the effect of diet type and animal strain. Results The fish oil fed F1B hamsters showed milky plasma after a 14-hour fast. Fish oil feeding caused accumulation of apolipoproteinB48 containing lipoprotein particles suggesting hindrance of triglyceride-rich lipoprotein clearance. There was no significant effect of diet or strain on hepatic or intestinal microsomal triglyceride transfer protein activity indicating that hyperlipidaemia is not due to an increase in the assembly or secretion of lipoprotein particles. F1B hamsters showed significantly reduced levels of lipoprotein lipase activity, which was inhibited by fish oil feeding. Conclusion Evidence is presented for the first time that alterations in

  7. Intensive voluntary wheel running may restore circadian activity rhythms and improves the impaired cognitive performance of arrhythmic Djungarian hamsters.

    Science.gov (United States)

    Weinert, Dietmar; Schöttner, Konrad; Müller, Lisa; Wienke, Andreas

    2016-01-01

    Circadian rhythms are highly important not only for the synchronization of animals and humans with their periodic environment but also for their fitness. Accordingly, the disruption of the circadian system may have adverse consequences. A certain number of animals in our breeding stock of Djungarian hamsters are episodically active throughout the day. Also body temperature and melatonin lack 24-h rhythms. Obviously in these animals, the suprachiasmatic nuclei (SCN) as the central pacemaker do not generate a circadian signal. Moreover, these so-called arrhythmic (AR) hamsters have cognitive deficits. Since motor activity is believed to stabilize circadian rhythms, we investigated the effect of voluntary wheel running. Hamsters were bred and kept under standardized housing conditions with food and water ad libitum and a 14 L/10 D lighting regimen. AR animals were selected according to their activity pattern obtained by means of passive infrared motion detectors. In a first step, the daily activity behavior was investigated for 3 weeks each without and with running wheels. To estimate putative photic masking effects, hamsters were exposed to light (LPs) and DPs and also released into constant darkness for a minimum of 3 weeks. A novel object recognition (NOR) test was performed to evaluate cognitive abilities both before and after 3 weeks of wheel availability. The activity patterns of hamsters with low wheel activity were still AR. With more intense running, daily patterns with higher values in the dark time were obtained. Obviously, this was due to masking as LPs did suppress and DPs induced motor activity. When transferred to constant darkness, in some animals the daily rhythm disappeared. In other hamsters, namely those which used the wheels most actively, the rhythm was preserved and free-ran, what can be taken as indication of a reconstitution of circadian rhythmicity. Also, animals showing a 24-h activity pattern after 3 weeks of extensive wheel running were

  8. Vaccination with Leishmania infantum acidic ribosomal P0 but not with nucleosomal histones proteins controls Leishmania infantum infection in hamsters.

    Science.gov (United States)

    Pereira, Lais; Abbehusen, Melissa; Teixeira, Clarissa; Cunha, Jurema; Nascimento, Ivan P; Fukutani, Kyioshi; dos-Santos, Washington; Barral, Aldina; de Oliveira, Camila Indiani; Barral-Netto, Manoel; Soto, Manoel; Brodskyn, Cláudia Ida

    2015-02-01

    Several intracellular Leishmania antigens have been identified in order to find a potential vaccine capable of conferring long lasting protection against Leishmania infection. Histones and Acid Ribosomal proteins are already known to induce an effective immune response and have successfully been tested in the cutaneous leishmaniasis mouse model. Here, we investigate the protective ability of L. infantum nucleosomal histones (HIS) and ribosomal acidic protein P0 (LiP0) against L. infantum infection in the hamster model of visceral leishmaniasis using two different strategies: homologous (plasmid DNA only) or heterologous immunization (plasmid DNA plus recombinant protein and adjuvant). Immunization with both antigens using the heterologous strategy presented a high antibody production level while the homologous strategy immunized group showed predominantly a cellular immune response with parasite load reduction. The pcDNA-LiP0 immunized group showed increased expression ratio of IFN-γ/IL-10 and IFN-γ/TGF-β in the lymph nodes before challenge. Two months after infection hamsters immunized with the empty plasmid presented a pro-inflammatory immune response in the early stages of infection with increased expression ratio of IFN-γ/IL-10 and IFN-γ/TGF-β, whereas hamsters immunized with pcDNA-HIS presented an increase only in the ratio IFN-γ/ TGF-β. On the other hand, hamsters immunized with LiP0 did not present any increase in the IFN-γ/TGF-β and IFN-γ/IL-10 ratio independently of the immunization strategy used. Conversely, five months after infection, hamsters immunized with HIS maintained a pro-inflammatory immune response (ratio IFN-γ/ IL-10) while pcDNA-LiP0 immunized hamsters continued showing a balanced cytokine profile of pro and anti-inflammatory cytokines. Moreover we observed a significant reduction in parasite load in the spleen, liver and lymph node in this group compared with controls. Our results suggest that vaccination with L. infantum LiP0

  9. Alternation between short- and long photoperiod reveals hypothalamic gene regulation linked to seasonal body weight changes in Djungarian hamsters (Phodopus sungorus).

    Science.gov (United States)

    Bank, J H H; Wilson, D; Rijntjes, E; Barrett, P; Herwig, A

    2017-07-01

    Djungarian hamsters are able to reduce their body weight by more than 30% in anticipation of the winter season. This particular adaptation to extreme environmental conditions is primarily driven by a natural reduction in day length and conserved under laboratory conditions. We used this animal model to investigate hypothalamic gene expression linked to body weight regulation behind this physiological phenomenon. After an initial collective short photoperiod (SP) adaptation for 14 weeks from a preceding long photoperiod (LP), hamsters were re-exposed to LP for either 6 or 14 weeks, followed by a second re-exposure to SP for 8 weeks. Our data showed that re-exposure to LP led to an increase in body weight. In the hypothalamus Dio2, Vimentin, Crbp1 and Grp50 expression increased, whereas expression of Dio3, Mct8 and Srif decreased. The changes in body weight and gene expression were reversible in most hamsters after a further re-exposure to SP following 6 or 14 weeks in LP. Interestingly, after 14 weeks in LP, body weight loss was pronounced in six hamsters re-exposed to SP, but five hamsters did not respond. In nonresponding hamsters, a different gene expression pattern was manifested, with the exception of Dio2, which was reduced not only in SP re-exposed hamsters, but also in hamsters maintained in LP. Taken together, these data suggest that body weight regulation appears to be tightly linked to a co-ordinated regulation of several genes in the hypothalamus, including those involved in thyroid hormone metabolism. © 2017 British Society for Neuroendocrinology.

  10. Comparative study of the toxic effects of gallium arsenide, indium arsenide and arsenic trioxide following intratracheal instillations to the lung of Syrian golden hamsters.

    Science.gov (United States)

    Tanaka, A; Hirata, M; Omura, M; Zhao, M; Makita, Y; Yamazaki, K; Inoue, N; Gotoh, K

    2000-01-01

    Toxic effects of gallium arsenide (GaAs), indium arsenide (InAs) and arsenic trioxide (As2O3) were studied in male Syrian golden hamsters. GaAs (7.7 mg/kg) and As2O3 (1.3 mg/kg) particles were instilled intratracheally twice a week a total of 16 times, while InAs (7.7 mg/kg) was instilled a total of 14 times. As a control, hamsters were treated with the vehicle, phosphate buffer solution. During the instillation period, the cumulative body weight gain of the InAs-, but not the GaAs- or As2O3-treated hamsters was suppressed significantly, when compared with the control group. Slight to severe inflammatory responses were observed in the lung for all treatment groups. The most severe inflammatory change, characterized by an accumulation of neutrophils and macrophages, exudation, thickness of the pleura and fibrotic proliferation was found in the InAs-treated hamsters. Extensive alveolar or bronchiolar cell hyperplasia with or without keratinizing squamous cell metaplasia was observed in almost all the InAs-treated hamsters. Furthermore, squamous cell metaplasia or squamous cell hyperplasia developed in some of the InAs-treated hamsters, but not in the GaAs- or As2O3-treated hamsters. Slight to mild lesions were found in the convoluted tubules of the kidney in both the GaAs and InAs groups. From the present study, the toxic potency of these particles was provisionally estimated to be in the following order: InAs > GaAs > As2O3, at the dosage level used in this study. Furthermore, there was evidence that InAs particles could induce pulmonary, renal or systemic toxicity, and as such, InAs particles may produce pulmonary precancerous change when instilled intratracheally into hamsters.

  11. Comparative pattern of growth and development of Echinostoma paraensei (Digenea: Echinostomatidae) in hamster and Wistar rat using light and confocal laser scanning microscopy.

    Science.gov (United States)

    Souza, Joyce G R; Garcia, Juberlan S; Gomes, Ana Paula N; Machado-Silva, José Roberto; Maldonado, Arnaldo

    2017-12-01

    Echinostoma paraensei (Digenea: Echinostomatidae) lives in the duodenum and bile duct of rodents and is reported as a useful model for studies on the biology of flatworms. Here, we compared the growth and development of pre and post ovigerous worms collected 3, 7, 14 and 21 days post infection from experimentally infected hamster (permissive host) and Wistar rat (less permissive hosts). Linear measurements and ratios were examined by light (morphology and morphometry) and confocal laser scanning microscopy. At day 3, either worm from hamsters or rats were small with poorly developed gonads. At seven day, worms increased in size and morphometric differences between hosts are statistically significant after this time. In addition, adult worms (14 and 21 days of age) harvested from hamster showed developed gonads and vitelline glands laterally distributed on the body, whereas worms from rat showed atrophied reproductive system characterized by underdeveloped vitelline glands and stunted ovary. The worm rate recovery in rat decreased from 29.3% (day 7) to 20.6% (day 14) and 8% (day 21), whilst it remained around 37% in hamster. In conclusion, this is the first appointment demonstrating that low permissiveness influences the reproductive system of echinostome since the immature stages of development. The phenotypic analysis evidenced that hamster provides a more favorable microenvironment for gonads development than rat, confirming golden hamster as a permissive host, whereas Wistar rat is less permissive host. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Flank-marking behavior and the neural distribution of vasopressin innervation in golden hamsters with suprachiasmatic lesions.

    Science.gov (United States)

    Delville, Y; De Vries, G J; Schwartz, W J; Ferris, C F

    1998-12-01

    In golden hamsters, microinjections of arginine-vasopressin (AVP) within the anterior hypothalamus trigger a stereotyped scent-marking behavior, flank marking. Our experiment was carried out to test the contribution of AVP neurons within the suprachiasmatic nucleus (SCN) in the control of this behavior. Our results suggest that the SCN does not contribute to flank-marking behavior. Whereas SCN lesions disrupted circadian rhythms of wheel running, the same lesions did not disrupt flank-marking. The results also suggest that neurons located outside the SCN contribute significantly to the vasopressinergic innervation of the brain and the expression of AVP-dependent behaviors, such as flank-marking behavior. Although AVP-immunoreactive fibers were severely (ca. 95%) depleted from several forebrain areas in SCN-lesioned hamsters, the effect of the lesions was much more limited within the forebrain areas involved in flank-marking behavior as well as within the midbrain and hindbrain.

  13. The HaP-T1 Syrian golden hamster pancreatic cancer model: cell implantation is better than tissue implantation.

    Science.gov (United States)

    Abraham, Ajit T; Shah, Sudeep R; Davidson, Brian R

    2004-11-01

    Pancreatic cancer is characterized by a poor prognosis and an unsatisfactory response to conventional therapy. Appropriate experimental animal models that mimic the disease are essential to establish new therapies. The aim of this study was to compare homologous orthotopic cell implantation (OCI) and orthotopic tissue implantation (OTI) methods in the nitrosamine-derived HaP-T1 Syrian golden hamster pancreatic cancer model. Pancreatic tumors were induced in 32 Syrian hamsters by the OCI (n = 16) and OTI (n = 16) techniques. OTI and OCI subgroups (n = 4) were killed at 1, 2, 5, and 8 weeks post-implantation. Tumor uptake and growth and the rates of local invasion and metastases were compared at autopsy. Tumor uptake was 100% by OCI and 88% by OTI. Induced pancreatic tumors were significantly larger in the OCI group (mean weight, 1.7 g vs. 0.26 g, P cancer research.

  14. Tumor production in Syrian hamsters following inhalation of PuO2--ZrO2 aerosol

    International Nuclear Information System (INIS)

    Thomas, R.G.; Smith, D.M.

    1978-01-01

    Syrian golden hamsters of both sexes were exposed to aerosols of ZrO 2 containing PuO 2 . The starting material in the aerosol generator also had a small amount of 57 Co added as a tracer. The mixture of all three constituents was nebulized and the droplets passed through a heating column at 1000 0 C. Aerosol sampling was accomplished with a cascade impactor and electrostatic precipitator. The median aerodynamic diameters in all inhalation runs were approximately 2 μm with a geometric standard deviation of 2. One exposed group of 60 hamsters had 6-day lung burdens averaging 100 nCi. This group had a lung tumor incidence of 44% with an even distribution of adenomas and carcinomas. Two other groups had average 6-day lung burdens of 80 to 90 nCi plus 55 nCi of intravenously injected spheres localized in the lung. These animals had tumor incidences of approximately 30%

  15. Effects of harman and norharman on spontaneous and ultraviolet light-induced mutagenesis in cultured Chinese hamster cells

    International Nuclear Information System (INIS)

    Chang, C.C.; Castellazzi, M.; Glover, T.W.; Trosko, J.E.

    1978-01-01

    Nontoxic concentrations of harman and norharman were tested in cultured Chinese hamster cells for their effects on DNA repair and mutagenesis. The following effects of harman were observed: (a) the survival of ultraviolet light- or x-ray-damaged cells was reduced; (b) the ultraviolet light-induced unscheduled DNA synthesis was slightly inhibited; and (c) the frequency of spontaneous or ultraviolet light-induced ouabain-resistant (ouar) or 6-thioguanine-resistant (6-TGr) mutations was reduced. Furthermore, the effect of harman on survival and mutagenesis was greater than that of norharman and was detected primarily in treatments in which cells were exposed to harman immediately following ultraviolet light irradiation. Our data clearly indicate that harman decreases the capacity to repair DNA damage and fix mutations in Chinese hamster cells, possibly because of the intercalation properties of this compound

  16. [Histologic study on impeding leukoplakia carcinogenesis of golden hamster cheek pouch about Erigeron breviscapus (Vant) Hand-Mazz].

    Science.gov (United States)

    Zhou, C T; Zhong, W J; Hua, L; Hu, H F; Jin, Z G

    2000-06-01

    To observe the effect of Erigeron breviscapus (Vant) Hand Mazz (HEr) in impeding oral leukoplakia carcinogenesis, and to seek effective Chinese herb medicine that can impede precarcinoma of oral mucosas. 132 golden hamsters were randomly divided into model group (60 animals), HEr group (60 animals), and control group 12 animals. Salley's leukoplakia carcinogenesis model of golden hamster cheek pouch was used in this study. HEr was injected into the stomach to impede evolution of carcinogenesis. Pathological specimens were observed via naked eye and light microscope between model group and HEr group. Results were compared. Observation via naked-eye showed that leukoplakia rate of HEr group (18.2%) was lower than that of model group (27.3%). Observation via light microscope showed that carcinogenesis rate descended one fold and displasia rate descended 0.4 fold in HEr group. HEr has exact effect in impeding leukoplakia carcinogenesis.

  17. Plating efficiency for primary hamster embryo cells as an index of efficacy of fetal bovne serum for cell culture.

    Science.gov (United States)

    Goodheart, C R; Castro, B C; Giviers, A; Regnier, P R

    1973-10-01

    Attachment and growth of mammalian cells plated at low cell density require optimum conditions for the cells to form colonies. Reliability, reproducibility, and validity of the plating efficiency test for evaluating cell culture sera were determined by measuring the plating efficiency of 37 lots of fetal bovine serum obtained from 8 suppliers (5 lots from each of 7, 2 lots from 1 supplier), by using hamster embryo fibroblasts plated at low cell density. The test revealed considerable variation between lots of serum and between suppliers. The five lots from some suppliers had consistently high plating efficiencies, whereas one or more lots from other suppliers had quite low efficiencies. The results were reproducible in repeated tests, and control experiments indicated that the test measured the efficiency of the test serum independently of the efficiency of the serum used for the primary outgrowth of the hamster embryo cells.

  18. Plating Efficiency for Primary Hamster Embryo Cells as an Index of Efficacy of Fetal Bovine Serum for Cell Culture

    Science.gov (United States)

    Goodheart, C. R.; Casto, B. C.; Zwiers, A.; Regnier, P. R.

    1973-01-01

    Attachment and growth of mammalian cells plated at low cell density require optimum conditions for the cells to form colonies. Reliability, reproducibility, and validity of the plating efficiency test for evaluating cell culture sera were determined by measuring the plating efficiency of 37 lots of fetal bovine serum obtained from 8 suppliers (5 lots from each of 7, 2 lots from 1 supplier), by using hamster embryo fibroblasts plated at low cell density. The test revealed considerable variation between lots of serum and between suppliers. The five lots from some suppliers had consistently high plating efficiencies, whereas one or more lots from other suppliers had quite low efficiencies. The results were reproducible in repeated tests, and control experiments indicated that the test measured the efficiency of the test serum independently of the efficiency of the serum used for the primary outgrowth of the hamster embryo cells. PMID:4584591

  19. Significant prolongation of hamster liver transplant survival in Lewis rats by total-lymphoid irradiation, cyclosporine, and splenectomy

    International Nuclear Information System (INIS)

    Yamaguchi, Y.; Halperin, E.C.; Harland, R.C.; Wyble, C.; Bollinger, R.R.

    1990-01-01

    The effects of total lymphoid irradiation, cyclosporine and splenectomy alone and in combination have been studied in liver transplants from the LVG hamster to the LEW rat. Neither CsA alone, splenectomy alone, nor TLI alone prolonged graft survival. CsA/splenectomy and TLI/CsA produced significant prolongation of graft survival. TLI/CsA/splenectomy prolonged graft survival by over sixfold compared with controls. While CsA alone was ineffective in reducing lymphocytotoxic antidonor antibody, splenectomy alone or CsA/splenectomy did significantly suppress production of antibody. Only very low levels of antibody could be detected in animals treated with TLI/CsA/splenectomy. TLI/CsA/splenectomy has an immunosuppressive effect sufficient to significantly prolong liver graft survival in the LVG hamster to LEW rat combination and may represent a promising treatment protocol in experimental cross-species transplantation

  20. Photoperiodic regulation of body mass, food intake, hibernation, and reproduction in intact and castrated male European hamsters, Cricetus cricetus.

    Science.gov (United States)

    Canguilhem, B; Vaultier, J P; Pévet, P; Coumaros, G; Masson-Pévet, M; Bentz, I

    1988-08-01

    A group of sexually active male European hamsters were raised either in short-photoperiod conditions (SP; LD 8:16) or in long-photoperiod conditions (LP; LD 16:8) from their capture at the end of the hibernation period. Another group of hamsters was castrated in April and gonadectomized animals were maintained in SP and cold (7 degrees C) or in a succession of SP and LP plus cold. Another group, castrated in May or in September and raised in LP conditions, was transferred in September to SP conditions and cold. 1. Normal hamsters raised in continuous SP or LP apparently did not show signs of rhythmic behavior, except possibly in gonadal activity. 2. Body weight increased continuously, plasma testosterone levels oscillated between 1.5 and 2.5 ng/ml, and animals raised in SP and in cold did not enter hibernation. 3. Similar results were also found in castrated animals kept in SP conditions and cold. 4. The sequence LP-SP induced a decrease in food intake and body weight and a decrease in plasma testosterone levels and triggered entry into hibernation in both intact and castrated animals. 5. After 6 months continuously in SP and with exposure to cold spontaneous recrudescence in food intake and body weight occurred and hibernation ended in both intact and castrated animals. 6. In normal animals a spontaneous increase in plasma testosterone levels was observed. 7. In both normal and gonadectomized animals the phase of refractoriness could be broken by exposure to LP conditions. 8. The critical photoperiod lies between 15 and 15.5 h. These results demonstrate that the European hamster is a photoperiodic species.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Endogenous, photoperiodic and hormonal control of the body weight rhythm in the female European hamster, Cricetus cricetus.

    Science.gov (United States)

    Canguilhem, B; Masson-Pévet, M; Pévet, P; Bentz, I

    1992-03-01

    1. Body weight and hibernation rhythms were followed on normal and castrated female European hamsters raised in different conditions of photoperiod and ambient temperature. 2. In the normal females, the photoperiod was more effective than the ambient temperature regarding the control of the body weight rhythm. 3. In the castrated females, testosterone was more effective than oestradiol in suppressing both body weight and hibernation rhythms. 4. In short photoperiod conditions, the existence of endogenous rhythmicity depends upon prior photoperiodic exposure of the animals.

  2. Observation of Chinese Hamster Ovary Cells retained inside the non-woven fiber matrix of the CellTank bioreactor.

    Science.gov (United States)

    Zhang, Ye; Chotteau, Véronique

    2015-12-01

    This data article shows how the recombinant Chinese Hamster Ovary (CHO) cells are located in the interstices of the matrix fibers of a CellTank bioreactor after completion of a perfusion culture, supporting the article entitled "Very high cell density perfusion of CHO cells anchored in a non-woven matrix-based bioreactor" by Zhang et al. [1]. It provides a visualization of the cell distribution in the non-woven fiber matrix in a deeper view.

  3. The essential structures of ISP-I that influence serine palmitoyltransferase inhibition in Chinese hamster ovary cells.

    Science.gov (United States)

    Mizukoshi, Koji; Matsumoto, Katsuo; Hirose, Ryoji; Fujita, Tetsuro

    2012-01-01

    We investigated the structure-activity relationship between various ISP-I (myriocin, thermozymocidin) analogous which has sphingosine-like structure and serine palmitoyltransferase (SPT) in Chinese hamster ovary (CHO) cells utilizing sphingolipid production as a marker. Our data suggest that the double bond and/or ketone group within the alkyl chain as well as the alkyl chain are necessary for ISP-I to inhibit SPT. In addition, a serine structure is necessary for SPT inhibitory activity, which confirms previous findings.

  4. Auto-inhibitory regulation of angiotensin II functionality in hamster aorta during the early phases of dyslipidemia.

    Science.gov (United States)

    Pereira, Priscila Cristina; Pernomian, Larissa; Côco, Hariane; Gomes, Mayara Santos; Franco, João José; Marchi, Kátia Colombo; Hipólito, Ulisses Vilela; Uyemura, Sergio Akira; Tirapelli, Carlos Renato; de Oliveira, Ana Maria

    2016-06-15

    Emerging data point the crosstalk between dyslipidemia and renin-angiotensin system (RAS). Advanced dyslipidemia is described to induce RAS activation in the vasculature. However, the interplay between early dyslipidemia and the RAS remains unexplored. Knowing that hamsters and humans have a similar lipid profile, we investigated the effects of early and advanced dyslipidemia on angiotensin II-induced contraction. Cumulative concentration-response curves for angiotensin II (1.0pmol/l to 1.0µmol/l) were obtained in the hamster thoracic aorta. We also investigated the modulatory action of NAD(P)H oxidase on angiotensin II-induced contraction using ML171 (Nox-1 inhibitor, 0.5µmol/l) and VAS2870 (Nox-4 inhibitor, 5µmol/l). Early dyslipidemia was detected in hamsters treated with a cholesterol-rich diet for 15 days. Early dyslipidemia decreased the contraction induced by angiotensin II and the concentration of Nox-4-derived hydrogen peroxide. Advanced dyslipidemia, observed in hamsters treated with cholesterol-rich diet for 30 days, restored the contractile response induced by angiotensin II by compensatory mechanism that involves Nox-4-mediated oxidative stress. The hyporresponsiveness to angiotensin II may be an auto-inhibitory regulation of the angiotensinergic function during early dyslipidemia in an attempt to reduce the effects of the upregulation of the vascular RAS during the advanced stages of atherogenesis. The recovery of vascular angiotensin II functionality during the advanced phases of dyslipidemia is the result of the upregulation of redox-pro-inflammatory pathway that might be most likely involved in atherogenesis progression rather than in the recovery of vascular function. Taken together, our findings show the early phase of dyslipidemia may be the most favorable moment for effective atheroprotective therapeutic interventions. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Treatment of nitrosamine-induced pancreatic tumors in hamsters with analogs of somatostatin and luteinizing hormone-releasing hormone

    Energy Technology Data Exchange (ETDEWEB)

    Paz-Bouza, J.I.; Redding, T.W.; Schally, A.V.

    1987-02-01

    Pancreatic ductal adenocarcinoma was induced in female Syrian golden hamsters by injecting N-nitrosobis(2-oxopropyl)amine (BOP) once a week at a dose of 10 mg per kg of body weight for 18 weeks. Hamsters were then treated with somatostatin analog (RC-160) or with (6-D-tryptophan)luteinizing hormone-releasing hormone ((D-Trp/sup 6/)LH-RH) delayed delivery systems. After 18 weeks of BOP administration, the hamsters were divided into three groups of 10-20 animals each. Group I consisted of untreated controls, group II was injected with RC-160, and group III was injected with (D-Trp/sub 2/)LH-RH. A striking decrease in tumor weight and volume was obtained in animals treated with (D-Trp/sup 6/)LH-RH or with the somatostatin analog RC-160. After 45 days of treatment with either analog, the survival rate was significantly higher in groups II and III (70%), as compared with the control group (35%). The studies, done by light microscopy, high-resolution microscopy, and electron microscopy, showed a decrease in the total number of cancer cells and changes in the epithelium, connective tissue, and cellular organelles in groups II and III treated with the hypothalamic analogs as compared to controls. These results in female hamsters with induced ductal pancreatic tumors confirm and extend the authors findings, obtained in male animals with transplanted tumors, that (D-Trp/sub 6/)LH-RH and somatostatin analogs inhibit the growth of pancreatic cancers.

  6. Cloning, reformatting, and small-scale expression of monoclonal antibody isolated from mouse, rat, or hamster hybridoma.

    Science.gov (United States)

    Loyau, Jeremy; Rousseau, François

    2014-01-01

    The hybridoma technology, first described in 1975 by Milstein and Köhler, is still to date one of the most commonly used approaches to produce monoclonal antibodies. However, despite many advantages, this approach suffers from limitations like limited antibody productivity. Here, we describe a method for efficient cloning of antibody VH and VL produced by mouse, rat, or hamster hybridoma before reformatting in full-length IgG and small-scale expression in mammalian cell line.

  7. Observation of Chinese Hamster Ovary Cells retained inside the non-woven fiber matrix of the CellTank bioreactor

    OpenAIRE

    Zhang, Ye; Chotteau, V?ronique

    2015-01-01

    This data article shows how the recombinant Chinese Hamster Ovary (CHO) cells are located in the interstices of the matrix fibers of a CellTank bioreactor after completion of a perfusion culture, supporting the article entitled “Very high cell density perfusion of CHO cells anchored in a non-woven matrix-based bioreactor” by Zhang et al. [1]. It provides a visualization of the cell distribution in the non-woven fiber matrix in a deeper view.

  8. Effect of exercise on photoperiod-regulated hypothalamic gene expression and peripheral hormones in the seasonal Dwarf Hamster Phodopus sungorus.

    Directory of Open Access Journals (Sweden)

    Ines Petri

    Full Text Available The Siberian hamster (Phodopus sungorus is a seasonal mammal responding to the annual cycle in photoperiod with anticipatory physiological adaptations. This includes a reduction in food intake and body weight during the autumn in anticipation of seasonally reduced food availability. In the laboratory, short-day induction of body weight loss can be reversed or prevented by voluntary exercise undertaken when a running wheel is introduced into the home cage. The mechanism by which exercise prevents or reverses body weight reduction is unknown, but one hypothesis is a reversal of short-day photoperiod induced gene expression changes in the hypothalamus that underpin body weight regulation. Alternatively, we postulate an exercise-related anabolic effect involving the growth hormone axis. To test these hypotheses we established photoperiod-running wheel experiments of 8 to 16 weeks duration assessing body weight, food intake, organ mass, lean and fat mass by magnetic resonance, circulating hormones FGF21 and insulin and hypothalamic gene expression. In response to running wheel activity, short-day housed hamsters increased body weight. Compared to short-day housed sedentary hamsters the body weight increase was accompanied by higher food intake, maintenance of tissue mass of key organs such as the liver, maintenance of lean and fat mass and hormonal profiles indicative of long day housed hamsters but there was no overall reversal of hypothalamic gene expression regulated by photoperiod. Therefore the mechanism by which activity induces body weight gain is likely to act largely independently of photoperiod regulated gene expression in the hypothalamus.

  9. Effects of turmeric and its active principle, curcumin, on bleomycin-induced chromosome aberrations in Chinese hamster ovary cells

    OpenAIRE

    Araújo, Maria Cristina P.; Dias, Francisca da Luz; Kronka, Sergio N. [UNESP; Takahashi, Catarina S.

    1999-01-01

    Naturally occurring antioxidants have been extensively studied for their capacity to protect organisms and cells from oxidative damage. Many plant constituents including turmeric and curcumin appear to be potent antimutagens and antioxidants. The effects of turmeric and curcumin on chromosomal aberration frequencies induced by the radiomimetic agent bleomycin (BLM) were investigated in Chinese hamster ovary (CHO) cells. Three concentrations of each drug, turmeric (100, 250 and 500 mg/ml) and ...

  10. Characterization of Disease Course after Intramuscular or Intranasal Exposure to Sin Nombre Virus in Immunosuppressed Syrian Hamsters

    Science.gov (United States)

    2017-04-03

    specific drugs or vaccines to 52 treat or prevent HPS makes medical countermeasure development imperative. Well-53 TR-17-048 DISTRIBUTION STATEMENT A...component for elucidating viral pathogenesis, testing and 190 evaluating vaccines , antivirals, and biologicals, and the potential licensing of those products...the ANDV/hamster model and 262 human HPS disease. Further refinement of this model allows the testing of vaccines and medical 263 countermeasures to

  11. Effect of Exercise on Photoperiod-Regulated Hypothalamic Gene Expression and Peripheral Hormones in the Seasonal Dwarf Hamster Phodopus sungorus

    Science.gov (United States)

    Petri, Ines; Dumbell, Rebecca; Scherbarth, Frank; Steinlechner, Stephan; Barrett, Perry

    2014-01-01

    The Siberian hamster (Phodopus sungorus) is a seasonal mammal responding to the annual cycle in photoperiod with anticipatory physiological adaptations. This includes a reduction in food intake and body weight during the autumn in anticipation of seasonally reduced food availability. In the laboratory, short-day induction of body weight loss can be reversed or prevented by voluntary exercise undertaken when a running wheel is introduced into the home cage. The mechanism by which exercise prevents or reverses body weight reduction is unknown, but one hypothesis is a reversal of short-day photoperiod induced gene expression changes in the hypothalamus that underpin body weight regulation. Alternatively, we postulate an exercise-related anabolic effect involving the growth hormone axis. To test these hypotheses we established photoperiod-running wheel experiments of 8 to 16 weeks duration assessing body weight, food intake, organ mass, lean and fat mass by magnetic resonance, circulating hormones FGF21 and insulin and hypothalamic gene expression. In response to running wheel activity, short-day housed hamsters increased body weight. Compared to short-day housed sedentary hamsters the body weight increase was accompanied by higher food intake, maintenance of tissue mass of key organs such as the liver, maintenance of lean and fat mass and hormonal profiles indicative of long day housed hamsters but there was no overall reversal of hypothalamic gene expression regulated by photoperiod. Therefore the mechanism by which activity induces body weight gain is likely to act largely independently of photoperiod regulated gene expression in the hypothalamus. PMID:24603871

  12. Hypothalamic over-expression of VGF in the Siberian hamster increases energy expenditure and reduces body weight gain.

    Science.gov (United States)

    Lewis, Jo E; Brameld, John M; Hill, Phil; Cocco, Cristina; Noli, Barbara; Ferri, Gian-Luca; Barrett, Perry; Ebling, Francis J P; Jethwa, Preeti H

    2017-01-01

    VGF (non-acronymic) was first highlighted to have a role in energy homeostasis through experiments involving dietary manipulation in mice. Fasting increased VGF mRNA in the Arc and levels were subsequently reduced upon refeeding. This anabolic role for VGF was supported by observations in a VGF null (VGF-/-) mouse and in the diet-induced and gold-thioglucose obese mice. However, this anabolic role for VGF has not been supported by a number of subsequent studies investigating the physiological effects of VGF-derived peptides. Intracerebroventricular (ICV) infusion of TLQP-21 increased resting energy expenditure and rectal temperature in mice and protected against diet-induced obesity. Similarly, ICV infusion of TLQP-21 into Siberian hamsters significantly reduced body weight, but this was due to a decrease in food intake, with no effect on energy expenditure. Subsequently NERP-2 was shown to increase food intake in rats via the orexin system, suggesting opposing roles for these VGF-derived peptides. Thus to further elucidate the role of hypothalamic VGF in the regulation of energy homeostasis we utilised a recombinant adeno-associated viral vector to over-express VGF in adult male Siberian hamsters, thus avoiding any developmental effects or associated functional compensation. Initially, hypothalamic over-expression of VGF in adult Siberian hamsters produced no effect on metabolic parameters, but by 12 weeks post-infusion hamsters had increased oxygen consumption and a tendency to increased carbon dioxide production; this attenuated body weight gain, reduced interscapular white adipose tissue and resulted in a compensatory increase in food intake. These observed changes in energy expenditure and food intake were associated with an increase in the hypothalamic contents of the VGF-derived peptides AQEE, TLQP and NERP-2. The complex phenotype of the VGF-/- mice is a likely consequence of global ablation of the gene and its derived peptides during development, as well

  13. Unrefined and refined black raspberry seed oils significantly lower triglycerides and moderately affect cholesterol metabolism in male Syrian hamsters.

    Science.gov (United States)

    Ash, Mark M; Wolford, Kate A; Carden, Trevor J; Hwang, Keum Taek; Carr, Timothy P

    2011-09-01

    Unrefined and refined black raspberry seed oils (RSOs) were examined for their lipid-modulating effects in male Syrian hamsters fed high-cholesterol (0.12% g/g), high-fat (9% g/g) diets. Hamsters fed the refined and the unrefined RSO diets had equivalently lower plasma total cholesterol and high-density lipoprotein (HDL) cholesterol in comparison with the atherogenic coconut oil diet. The unrefined RSO treatment group did not differ in liver total and esterified cholesterol from the coconut oil-fed control animals, but the refined RSO resulted in significantly elevated liver total and esterified cholesterol concentrations. The unrefined RSO diets significantly lowered plasma triglycerides (46%; P=.0126) in comparison with the coconut oil diet, whereas the refined RSO only tended to lower plasma triglyceride (29%; P=.1630). Liver triglyceride concentrations were lower in the unrefined (46%; P=.0002) and refined (36%; P=.0005) RSO-fed animals than the coconut oil group, with the unrefined RSO diet eliciting a lower concentration than the soybean oil diet. Both RSOs demonstrated a null or moderate effect on cholesterol metabolism despite enrichment in linoleic acid, significantly lowering HDL cholesterol but not non-HDL cholesterol. Dramatically, both RSOs significantly reduced hypertriglyceridemia, most likely due to enrichment in α-linolenic acid. As a terrestrial source of α-linolenic acid, black RSOs, both refined and unrefined, provide a promising alternative to fish oil supplementation in management of hypertriglyceridemia, as demonstrated in hamsters fed high levels of dietary triglyceride and cholesterol.

  14. Adaptation of intestinal enzymes to seasonal and dietary changes in a hibernator: the European hamster (Cricetus cricetus).

    Science.gov (United States)

    Galluser, M; Raul, F; Canguilhem, B

    1988-01-01

    Effects of diet, hibernation and seasonal variations on hydrolase activities were determined in mucosa and purified brush border membranes of the small intestine of European hamsters. Wild hamsters captured in April and fed for several weeks with an equilibrated laboratory chow (20% protein, 50% carbohydrates) exhibited a rise in disaccharidase activities (sucrase, isomaltase, lactase) but no changes in aminopeptidase N activity. During deep hibernation, in contrast to sucrase and isomaltase activities which showed only minor changes, lactase activity was significantly enhanced along the jejunoileum, and aminopeptidase N activity was maximum in the ileum. After a short period (48 h) of wakefulness and feeding following 10 days of starvation during the hibernation period, the activities of the disaccharidases and of aminopeptidase N returned to values measured in active animals. In contrast to the nutritional state, which has an important impact on the activities of intestinal enzymes, season has little effect on the intestine of the active animal under a controlled environment. The pattern of enzyme activities which occurs along the small intestine in the hibernating animal may be a prerequisite for optimum digestion during the short phases of waking during the hibernation period of the European hamster.

  15. Effect of Urtica Dioica Extract on Histological and Histometrical Changes of Testis of Hamster after Testosteron Administration

    Directory of Open Access Journals (Sweden)

    Hassan Morovvati

    2013-11-01

    Full Text Available Background: Hyperactivity of testosterone is one cause of infertility and its incorrect use can produces reproductive disorders. Nettle (Urtica dioica has antiandrogenic effect and may antagonized effect of testosterone. In present study structure of testes of golden hamster was evaluated after testosterone and extract. Materials and Methods: In this experimental and animal modeling study, twenty male mature hamsters were divided to 4 groups, group 1 was control, group 2 received testosterone at dose 3 mg/kg subcutaneously, group 3 received nettle extract dose 30 mg/kg orally and group 4 received testosterone and nettle for 30 days daily. The hamsters were euthanized and testes were removed and detected macroscopic parameters (weight, height, wide and volume and fixed with formalin. The samples were sectioned and colored with H & E. Results: The volume, weight, length and wide of testes was at least in testosterone group and statistically was lesser than control and testosterone -nettle group (p<0.05, but did not the height epithelium of seminifer tubules, compact of spermatogenic cells and number of serotolli cells in testosterone group was lesser than control group significantly (p<0.05.Conclusion: The nettle extract decreased histological changes of testes by testosterone and improved its structure.

  16. Ionic imbalance and lack of effect of adjuvant treatment with methylene blue in the hamster model of leptospirosis

    Directory of Open Access Journals (Sweden)

    Cleiton Silva Santos

    2013-06-01

    Full Text Available Leptospirosis in humans usually involves hypokalaemia and hypomagnesaemia and the putative mechanism underlying such ionic imbalances may be related to nitric oxide (NO production. We previously demonstrated the correlation between serum levels of NO and the severity of renal disease in patients with severe leptospirosis. Methylene blue inhibits soluble guanylyl cyclase (downstream of the action of any NO synthase isoforms and was recently reported to have beneficial effects on clinical and experimental sepsis. We investigated the occurrence of serum ionic changes in experimental leptospirosis at various time points (4, 8, 16 and 28 days in a hamster model. We also determined the effect of methylene blue treatment when administered as an adjuvant therapy, combined with late initiation of standard antibiotic (ampicillin treatment. Hypokalaemia was not reproduced in this model: all of the groups developed increased levels of serum potassium (K. Furthermore, hypermagnesaemia, rather than magnesium (Mg depletion, was observed in this hamster model of acute infection. These findings may be associated with an accelerated progression to acute renal failure. Adjuvant treatment with methylene blue had no effect on survival or serum Mg and K levels during acute-phase leptospirosis in hamsters.

  17. Destruction of the hepatocyte junction by intercellular invasion of Leptospira causes jaundice in a hamster model of Weil's disease.

    Science.gov (United States)

    Miyahara, Satoshi; Saito, Mitsumasa; Kanemaru, Takaaki; Villanueva, Sharon Y A M; Gloriani, Nina G; Yoshida, Shin-ichi

    2014-08-01

    Weil's disease, the most severe form of leptospirosis, is characterized by jaundice, haemorrhage and renal failure. The mechanisms of jaundice caused by pathogenic Leptospira remain unclear. We therefore aimed to elucidate the mechanisms by integrating histopathological changes with serum biochemical abnormalities during the development of jaundice in a hamster model of Weil's disease. In this work, we obtained three-dimensional images of infected hamster livers using scanning electron microscope together with freeze-cracking and cross-cutting methods for sample preparation. The images displayed the corkscrew-shaped bacteria, which infiltrated the Disse's space, migrated between hepatocytes, detached the intercellular junctions and disrupted the bile canaliculi. Destruction of bile canaliculi coincided with the elevation of conjugated bilirubin, aspartate transaminase and alkaline phosphatase levels in serum, whereas serum alanine transaminase and γ-glutamyl transpeptidase levels increased slightly, but not significantly. We also found in ex vivo experiments that pathogenic, but not non-pathogenic leptospires, tend to adhere to the perijunctional region of hepatocyte couplets isolated from hamsters and initiate invasion of the intercellular junction within 1 h after co-incubation. Our results suggest that pathogenic leptospires invade the intercellular junctions of host hepatocytes, and this invasion contributes in the disruption of the junction. Subsequently, bile leaks from bile canaliculi and jaundice occurs immediately. Our findings revealed not only a novel pathogenicity of leptospires, but also a novel mechanism of jaundice induced by bacterial infection. © 2014 The Authors. International Journal of Experimental Pathology © 2014 International Journal of Experimental Pathology.

  18. Sex-specific effects of glucose deprivation on cell-mediated immunity and reproduction in Siberian hamsters (Phodopus sungorus).

    Science.gov (United States)

    Martin, Lynn B; Weil, Zachary M; Bowers, Stephanie L; Nelson, Randy J

    2008-07-01

    In most species, sexes differ in levels of parasitism. These differences have traditionally been believed to be static, but a capacity for adjusting anti-parasite investments would allow sexes to allocate resources adaptively contingent on environmental conditions. During stressful periods, such as a food shortage, allocation decisions would be mandated in males and females, but the biasing of resources may differ depending on the value of various physiological alternatives to the fitness of each sex. To determine whether sexes sacrifice immune or reproductive capacity when stressed, male and female Siberian hamsters (Phodopus sungorus) were pharmacologically deprived of glucose. Glucose deprivation was expected to compromise immune activity (delayed-type hypersensitivity) more than reproductive capacity in males because male fitness is limited by reproductive opportunities. The opposite was predicted for females because of the greater value of surviving to breed in favorable conditions. Contrary to expectations, glucoprivation compromised immune activity in female, but not male, hamsters. Conversely, glucoprivation reduced male, but not female, reproductive organ masses. These results may reflect the adjustments made by wild hamsters during food shortages, or they may be influenced by the study design; neither sex was permitted to incur other behavioral and physiological costs, such as lactation and parental care. Regardless, our results indicate that sex differences in parasitism are likely to be plastic in many circumstances, but further work in free-living animals is critical to ascertain whether results of the present study are naturally representative.

  19. [Mild intermittent aspirin-induced asthma in a patient who became asymptomatic after removal of pet hamsters from home].

    Science.gov (United States)

    Kawai, K; Shirai, T; Suzuki, K; Chida, K; Nakamura, H

    2000-04-01

    A 25-year-old woman was admitted to our hospital because of wheeze, dyspnea, nasal obstruction, epiphora, and ear fullness. These symptoms occurred 30 minutes after the intake of 200 mg of ibuprofen and 100 mg of norfloxacin, which had been prescribed by a local clinic for an upper respiratory tract infection. The patient had kept 20 hamsters indoors and a dog outside for 1 year and a half. During the 9 months prior to admission, she had experienced nocturnal asthmatic symptoms, which were controlled by oral theophylline on an as-needed basis. She had seasonal rhinitis, but no sinusitis or nasal polyps. Serum total IgE was 98 U/ml, and tests for specific IgE antibodies to hamster epithelium and dog epithelium were both positive (class 2). The provocative concentration of methacholine causing a 20% fall in FEV1 was 4.7 mg/ml. After removal of the hamsters from her home, the patient became asymptomatic without further medication, and her airway hyper-responsiveness was also alleviated. Although inhalation challenge with 5% tolmetin failed to induce a positive reaction, the diagnosis of aspirin-induced asthma was confirmed by single-blind oral challenge with 100 mg of ibuprofen. The patient exhibited mild airway responsiveness as well as mild sensitivity to nonsteroidal anti-inflammatory drugs, differing from the severe and intractable clinical features of typical aspirin-induced asthma.

  20. beta. -adrenergic ((/sup 3/H) CGP-12177) receptors are elevated in slices of soleus muscle from CHF 147 dystrophic hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Watson-Wright, W.M.; Wilkinson, M.

    1987-03-23

    The authors utilized a muscle slice technique to compare the ontogeny of cell surface ..beta..-adrenergic receptor binding in soleus and extensor digitorum longus (EDL) muscles of male Golden Syrian (GS) and Canadian Hybrid Farms 147 (CHF 147) dystrophic hamsters. Binding of the ..beta..-adrenergic antagonist, (/sup 3/H) CGP-12177 (CGP), to GS muscle slices was reversible, saturable, stereospecific and of high affinity. Bmax was higher in the soleus (2.57+/-.12 fmol/mg wet wt) than in the EDL (1.61+/-.17 fmol/mg wet wt) of adult animals while affinities were similar (0.35+/-.06 and 0.24+/-.04 nM respectively). No differences in binding characteristics were seen in EDL of GS compared to CHF 147 animals. In soleus slices from GS hamsters, Bmax was highest at 16 days of age (5.72+/-0.26 fmol/mg), decreased between 16 and 29 days and remained constant until 300 days (2.51+/-0.52 fmol/mg). In dystrophic soleus slices, Bmax was also higher at 16 days than at any other age but receptor number decreased gradually, remaining higher than in GS until 90 days of age (p<0.05). The failure of ..beta..-adrenergic receptor number to decrease at a normal rate may be implicated in the pathogenesis of hamster polymyopathy. 21 references, 5 figures, 1 table.

  1. β-adrenergic ([3H] CGP-12177) receptors are elevated in slices of soleus muscle from CHF 147 dystrophic hamsters

    International Nuclear Information System (INIS)

    Watson-Wright, W.M.; Wilkinson, M.

    1987-01-01

    The authors utilized a muscle slice technique to compare the ontogeny of cell surface β-adrenergic receptor binding in soleus and extensor digitorum longus (EDL) muscles of male Golden Syrian (GS) and Canadian Hybrid Farms 147 (CHF 147) dystrophic hamsters. Binding of the β-adrenergic antagonist, [ 3 H] CGP-12177 (CGP), to GS muscle slices was reversible, saturable, stereospecific and of high affinity. Bmax was higher in the soleus (2.57+/-.12 fmol/mg wet wt) than in the EDL (1.61+/-.17 fmol/mg wet wt) of adult animals while affinities were similar (0.35+/-.06 and 0.24+/-.04 nM respectively). No differences in binding characteristics were seen in EDL of GS compared to CHF 147 animals. In soleus slices from GS hamsters, Bmax was highest at 16 days of age (5.72+/-0.26 fmol/mg), decreased between 16 and 29 days and remained constant until 300 days (2.51+/-0.52 fmol/mg). In dystrophic soleus slices, Bmax was also higher at 16 days than at any other age but receptor number decreased gradually, remaining higher than in GS until 90 days of age (p<0.05). The failure of β-adrenergic receptor number to decrease at a normal rate may be implicated in the pathogenesis of hamster polymyopathy. 21 references, 5 figures, 1 table

  2. Comparsion of light dose on topical ALA-mediated photodynamic therapy for DMBA-induced hamster buccal pouch premalignant lesions

    Science.gov (United States)

    Yang, Deng-Fu; Tseng, Meng-Ke; Liu, Chung-Ji; Hsu, Yih-Chih

    2012-03-01

    Oral cancer has becomes the most prominent male cancer disease due to the local betel nut chewing habit combing with smoking and alcohol-drinking lifestyle. In order to minimize the systemic phototoxic effect of 5-aminolevulinic acid (ALA), this study was designed to use a topical ALA-mediated PDT for treatment of DMBA-induced hamster buccal pouch cancerous lesions. DMBA was applied to one of the buccal pouches of hamsters thrice a week for 8 to 10 weeks. Precancerous lesions were induced and proven by histological examination. These DMBA-induced cancerous lesions were used for testing the efficacy of topical ALA -mediated PDT. We found that ALA reached its peak level in cancerous lesions about 2.5 hrs after topical application of ALA gel. The precancerous lesions in hamsters were then treated with topical ALA -mediated PDT with light exposure dose of 75 and 100 J/cm2 using LED 635 nm Wonderlight device. It is suggesting that optimization of the given light dose is critical to the success of PDT results.

  3. Histamine-enhanced contractile responses of gastric smooth muscle via interstitial cells of Cajal in the Syrian hamster.

    Science.gov (United States)

    Naganuma, S; Shiina, T; Yasuda, S; Suzuki, Y; Shimizu, Y

    2017-11-21

    Gastric motility is controlled by the autonomic and enteric nervous systems and by interstitial cells of Cajal (ICCs). Although histamine is known to be released from enterochromaffin-like cells in the gastric mucosa, its regulatory roles in gastric motility are still controversial. Therefore, we investigated the functional roles of histamine in gastric motility. Stomach preparations from hamsters were used because the stomach of hamsters can be easily separated into the forestomach and the glandular stomach. A whole preparation of the stomach was mounted in a Magnus tube, and mechanical responses were recorded using a force transducer. Exogenous application of histamine had little effect on contractile activity of the glandular stomach. In contrast, the monoamine evoked regular, periodic contractions in the forestomach. An H1 receptor agonist reproduced the contractile responses and an H1 receptor antagonist blocked histamine-evoked contractions. Atropine and tetrodotoxin did not affect the histamine-evoked contractions. Pretreatment with drugs that inhibit the activity of ICCs abolished the effects of histamine. The findings suggest that histamine regulates gastric motility by acting on ICCs via H1 receptors in the hamster. The remarkable ability of histamine to induce rhythmic contractions would be useful for treatment of gastric dysmotility. © 2017 John Wiley & Sons Ltd.

  4. 12-O-Tetradecanoyl-phorbol-13-acetate and its relationship to SCE induction in Syrian and Chinese hamster cells

    International Nuclear Information System (INIS)

    Popescu, N.C.; Amsbaugh, S.C.; Larramendy, M.L.; DiPaolo

    1982-01-01

    12-O-Tetradecanoyl-phorbol-13-acetate (TPA) in conditions that produce enhancement of ultraviolet light (UV) and x-irradiation Syrian hamster embryo cell (HEC) transformation did not cause further increase in the sister chromatid exchange (SCE) frequency induced by UV and x-irradiation, two physical carcinogens that differ in their mode of DNA interaction and efficiency of SCE induction. Several factors which might influence SCE induction by TPA were studied on HEC and Chinese hamster V79-4 cells. Heat-inactivated serum was used because of the possibility that a serum component may interfere with TPA ability to cause SCE. TPA effect on SCE was determined at the first and second division post treatment on cells exposed to different 5-bromodeoxyuridine (BrdUrd) concentrations. Independent of BrdUrd concentration (1-10μg/ml medium) and the number of cells divisions post treatment, TPA (0.01-2μg/ml medium) was ineffective in inducing SCE in exponentially and stationary HEC cultures cultivated in medium supplemented with heat-inactivated serum. Also, TPA did not increase the SCE frequency in V79-4 Chinese hamster cells cultured in heat-activated or noninactivated serum. Although SCE induction, a cellular response to carcinogen-induced DNA damage, may be important for the induction of transformation by environmental agents, the enhancement of transformation frequency caused by TPA occurs without further DNA alterations involved in SCE formation

  5. Long-Term Single-Dose Efficacy of a Vesicular Stomatitis Virus-Based Andes Virus Vaccine in Syrian Hamsters

    Directory of Open Access Journals (Sweden)

    Joseph Prescott

    2014-01-01

    Full Text Available Andes virus (ANDV is highly pathogenic in humans and is the primary etiologic agent of hantavirus cardiopulmonary syndrome (HCPS in South America. Case-fatality rates are as high as 50% and there are no approved vaccines or specific therapies for infection. Our laboratory has recently developed a replication-competent recombinant vesicular stomatitis virus (VSV-based vaccine that expressed the glycoproteins of Andes virus in place of the native VSV glycoprotein (G. This vaccine is highly efficacious in the Syrian hamster model of HCPS when given 28 days before challenge with ANDV, or when given around the time of challenge (peri-exposure, and even protects when administered post-exposure. Herein, we sought to test the durability of the immune response to a single dose of this vaccine in Syrian hamsters. This vaccine was efficacious in hamsters challenged intranasally with ANDV 6 months after vaccination (p = 0.025, but animals were not significantly protected following 1 year of vaccination (p = 0.090. The decrease in protection correlated with a reduction of measurable neutralizing antibody responses, and suggests that a more robust vaccination schedule might be required to provide long-term immunity.

  6. Histological study of cell migration in the dermis of hamsters after immunisation with two different vaccines against visceral leishmaniasis.

    Science.gov (United States)

    Moreira, Nádia das Dores; Giunchetti, Rodolfo Cordeiro; Carneiro, Cláudia Martins; Vitoriano-Souza, Juliana; Roatt, Bruno Mendes; Malaquias, Luiz Cosme Cotta; Corrêa-Oliveira, Rodrigo; Reis, Alexandre Barbosa

    2009-04-15

    Vaccine candidates, including live and/or killed parasites, Leishmania-purified fractions, defined recombinant antigens and antigen-encoding DNA-plasmids have been proposed to use as vaccine anti-Leishmania. More recently, the hamsters have been used to pre-selection of antigens candidate to apply in further experiments using canine model. In this report we evaluated the kinetics of cell migration in dermal inflammatory infiltrate, circulating leukocytes and the presence of nitric oxide (NO)/induced nitric oxide synthase during the early (1-24h) and late (48-168h) periods following inoculation of hamsters with antigenic components of anti-canine visceral leishmaniasis vaccines Leishmune and Leishmania braziliensis antigen (LB) with and without saponin (Sap) adjuvant. Our results show that LB caused an early reduction of lymphocytes in the dermis while Sap and LBSap triggered a late recruitment, suggesting the role of the adjuvant in the traffic of antigen-presenting cells and the induction of lymphocyte migration. In that manner our results suggest that the kinetics of cell migration on hamster model may be of value in the selection of vaccine antigens prior the tests in dogs particularly in respect of the toxicity of the preparations.

  7. Toxicology and metabolism of nickel compounds. Progress report, December 1, 1978-November 30, 1979. [Hamsters and rats

    Energy Technology Data Exchange (ETDEWEB)

    Sunderman, F.W. Jr.

    1979-08-15

    The toxicology and metabolism of nickel compounds were investigated in rats and hamsters. The new knowledge includes; demonstration that nickel carbonyl is teratogenic for hamsters; elucidation of physiological factors which influence ..cap alpha..Ni/sub 3/S/sub 2/-induced erythrocytosis in rats; development of a sensitive assay for heme oxygenase activity in renal microsomes for use in studies of renal effects of nickel compounds; demonstration that administration of Ni(CO)/sub 4/ to rats inhibits incorporation of /sup 3/H-thymidine into DNA during hepatic regeneration; demonstration that clones of Syrian hamster fetal cells which have been transformed by in vitro exposure to ..cap alpha..Ni/sub 3/S/sub 2/ consistently cause sarcomas following sc injection into nude mice; demonstration that nickel carbonyl-cyclopentadiene dimer induces rhabdomyosarcomas following im injection in rats; observation of differences in carcinogenic activities of several insoluble nickel compounds; discovery that intraocular injection of ..cap alpha..Ni/sub 3/S/sub 2/ induces amelanotic melanomas in rats; and refinement of analytical methods for nickel in biological materials.

  8. Studies on the relationship between leptin secretion and several pregnancy-related hormones during pregnancy in the golden hamster

    International Nuclear Information System (INIS)

    Wang Chen; Yang Liguo; Gen Watanabe; Kazuyoshi Taya

    2003-01-01

    Objective: To determine the relationships between leptin secretion and several pregnancy related hormones, the body weight as well as food intaken in the golden hamster during pregnancy and early lactation. Methods: 100 golden hamsters were mated and divided into 16 groups. Blood specimens were taken at 11:00 daily and were determined for plasma leptin, growth hormone (GH), follicular stimulating hormone (FSH), luteinizing hormone (LH), progesterone estradiol and inhibin with RIA. Relationships between leptin level and food intake as well as material body weight were also noted. Results: A plasma leptin peak level occurred on day 12 of the pregnancy. Leptin levels were significantly correlated with levels of gonadal hormones but not with pituitary hormones. Food intake and material total body weight (including the fetus) bore no significant correlationship with plasma leptin throughout the whole pregnancy stage. However, if the fetus weight was subtracted, the net maternal body weight would be significantly correlated with the leptin concentration. Conclusion: These results suggest that leptin-resistance may exits in the golden hamster during pregnancy. Some pregnancy-related hormones, especially gonadal hormones, have regulatory effect on the secretion of leptin. Positive correlation between leptin and net maternal body weight suggests that leptin is still a signal of the body weight to the central nerves system during pregnancy

  9. The modifying effect of ibuprofen on total body irradiation-induced elevation of oxidative reactions in male hamsters

    International Nuclear Information System (INIS)

    Dokmeci, D.; Akpolat, M.; Aydogdu, N.; Uzal, C.; Turan, N.F.

    2004-01-01

    Radiation therapy plays an important role in curative and palliative treatments of malignant diseases. Because of the lipid component in the membrane, lipid peroxidation has been reported to be particularly susceptible to radiation damage. However, lipid peroxidation is reversed by cellular defense mechanisms, and the use of various antioxidants involved in these mechanisms have recently been suggested to be beneficial. It is known that ibuprofen has antioxidative and/or free radical scavenging activities. Our purpose is to examine the antioxidant capacity of ibuprofen in hamsters undergoing total body irradiation (TBI). Ibuprofen was given by gavage at dose of 10 mg/kg for 15 consecutive days. After this period, animals were exposed to TBI 60 Co gamma irradiation with a single dose of 8 Gy. After 24 h radiation exposure, the hamsters were killed and samples were taken from blood. Plasma thiobarbituric acid reactive substances (TBARS) increased significantly after radiation exposure, and ibuprofen diminished the amounts of TBARS. Significant protection of the radiation-induced changes in the activities of superoxide dismutase (SOD) and catalase was also recorded in the blood of ibuprofen-treated and -irradiated hamsters. These results suggest that ibuprofen with its antioxidant capacity could play a modulatory role against cellular damage effected by free radicals induced by TBI. (author)

  10. Reference Gene Selection in the Desert Plant <em>Eremosparton songoricuem>m>

    Directory of Open Access Journals (Sweden)

    Dao-Yuan Zhang

    2012-06-01

    Full Text Available <em>Eremosparton songoricum em>(Litv. Vass. (<em>E. songoricumem> is a rare and extremely drought-tolerant desert plant that holds promise as a model organism for the identification of genes associated with water deficit stress. Here, we cloned and evaluated the expression of eight candidate reference genes using quantitative real-time reverse transcriptase polymerase chain reactions. The expression of these candidate reference genes was analyzed in a diverse set of 20 samples including various <em>E. songoricumem> plant tissues exposed to multiple environmental stresses. GeNorm analysis indicated that expression stability varied between the reference genes in the different experimental conditions, but the two most stable reference genes were sufficient for normalization in most conditions.<em> EsEFem> and <em>Esα-TUB> were sufficient for various stress conditions, <em>EsEF> and <em>EsACT> were suitable for samples of differing germination stages, and <em>EsGAPDH>and <em>Es>UBQ em>were most stable across multiple adult tissue samples. The <em>Es18Sem> gene was unsuitable as a reference gene in our analysis. In addition, the expression level of the drought-stress related transcription factor <em>EsDREB2em>> em>verified the utility of<em> E. songoricumem> reference genes and indicated that no single gene was adequate for normalization on its own. This is the first systematic report on the selection of reference genes in <em>E. songoricumem>, and these data will facilitate future work on gene expression in this species.

  11. In-vivo monitoring of development of cholangiocarcinoma induced with C. sinensis and N-nitrosodimethylamine in Syrian golen hamsters using ultrasonography and magnetic resonance imaging: a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Woo, Hyunsik [SMG-SNU Boramae Medical Center, Department of Radiology, Seoul (Korea, Republic of); Han, Joon Koo; Kim, Jung Hoon [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Hong, Sung-Tae [Seoul National University, Department of Parasitology, College of Medicine, Seoul (Korea, Republic of); Uddin, M.H. [Seoul National University, Adult Stem Cell Research Center, Laboratory of Stem Cell and Tumor Biology, Department of Veterinary Public Health, College of Veterinary Medicine, Seoul (Korea, Republic of); Jang, Ja-June [Seoul National University, Department of Pathology, College of Medicine, Seoul (Korea, Republic of)

    2017-04-15

    The purpose of this study is to evaluate high-resolution ultrasound and magnetic resonance imaging (MRI) in monitoring of cholangiocarcinoma in the hamsters with C. sinensis infection and N-nitrosodimethylamine (NDMA). Twenty-four male Syrian golden hamsters of were divided into four groups composed of five hamsters as control, five hamsters receiving 30 metacercariae of C. sinensis per each hamster, five hamsters receiving NDMA in drinking water, and nine hamsters receiving both metacercariae and NDMA. Ultrasound was performed every other week from baseline to the 12th week of infection. MRI and histopathologic examination was done from the 4th week to 12th week. Cholangiocarcinomas appeared as early as the 6th week of infection. There were 12 cholangiocarcinomas, nine and ten of which were demonstrated by ultrasound and MRI, respectively. Ultrasound and MRI findings of cholangiocarcinomas in the hamsters were similar to those of the mass-forming intrahepatic cholangiocarcinomas in humans. Ultrasound and MRI also showed other findings of disease progression such as periductal increased echogenicity or signal intensity, ductal dilatation, complicated cysts, and sludges in the gallbladder. High-resolution ultrasound and MRI can monitor and detect the occurrence of cholangiocarcinoma in the hamsters non-invasively. (orig.)

  12. In-vivo monitoring of development of cholangiocarcinoma induced with C. sinensis and N-nitrosodimethylamine in Syrian golen hamsters using ultrasonography and magnetic resonance imaging: a preliminary study

    International Nuclear Information System (INIS)

    Woo, Hyunsik; Han, Joon Koo; Kim, Jung Hoon; Hong, Sung-Tae; Uddin, M.H.; Jang, Ja-June

    2017-01-01

    The purpose of this study is to evaluate high-resolution ultrasound and magnetic resonance imaging (MRI) in monitoring of cholangiocarcinoma in the hamsters with C. sinensis infection and N-nitrosodimethylamine (NDMA). Twenty-four male Syrian golden hamsters of were divided into four groups composed of five hamsters as control, five hamsters receiving 30 metacercariae of C. sinensis per each hamster, five hamsters receiving NDMA in drinking water, and nine hamsters receiving both metacercariae and NDMA. Ultrasound was performed every other week from baseline to the 12th week of infection. MRI and histopathologic examination was done from the 4th week to 12th week. Cholangiocarcinomas appeared as early as the 6th week of infection. There were 12 cholangiocarcinomas, nine and ten of which were demonstrated by ultrasound and MRI, respectively. Ultrasound and MRI findings of cholangiocarcinomas in the hamsters were similar to those of the mass-forming intrahepatic cholangiocarcinomas in humans. Ultrasound and MRI also showed other findings of disease progression such as periductal increased echogenicity or signal intensity, ductal dilatation, complicated cysts, and sludges in the gallbladder. High-resolution ultrasound and MRI can monitor and detect the occurrence of cholangiocarcinoma in the hamsters non-invasively. (orig.)

  13. Características epidemiológicas da leishmaniose tegumentar americana em uma região endêmica do Estado da Bahia: II leishmaniose canina

    Directory of Open Access Journals (Sweden)

    Air C. Barretto

    1984-06-01

    Full Text Available Um inquérito em cães realizado na região de Três Braços, Bahia, mostrou que 3,0% de 98 animais tinham amastigotas em lesões de pele. Parasitos não foram encontrados em pele normal da orelha. De uma amostra selecionada de 13 cães, portadores de lesão cutânea ativa, nove (69,2% deles estavam comprovadamente infectados. Sete amostras de lesão produziram infecção em hamsters. O estudo biológico (crescimento em meio de cultura, evolução da lesão em hamster e desenvolvimento no tubo digestivo de Lutzomyia longipalpis identificou o parasito como pertencente ao complexo L. braziliensis. A caracterização bioquímica (mobilidade eletroforética de enzimas em placas de acetato de celulose e o estudo imunotaxonômico (anticorpos monoclonais definiram as amostras como L. braziliensis braziliensis. O papel do cão como um possível reservatório de L. b. braziliensis na região de Três Braços é discutido.During a survey of domestic and hunting dogs conducted in the Três Braços region, State of Bahia, 3,0% of 98 dogs had amastigotes in skin lesions. Parasites were not found in normal ear skin. In a nonrandomly selected sample of 13 dogs with active cutaneous lesions, infection was confirmed in nine (69,2%. Tissue biopsies from seven dog lesions produced infection in hamsters. The biological behaviour of the parasite (rate of growth in culture media, evolution of lesions in hamsters and development in the gut of Lutzomyia longipalpis, identified it to the Leishmania braziliensis complex. Characterization by biochemical means (eletrophoretic mobility of enzymes in cellulose acetate plates and immunotaxonomic studies (monoclonal antibodies defined the strains as L. braziliensis braziliensis. The role of dogs as a possible reservoir host of L. b. braziliensis in Três Braços region is discussed.

  14. Apoptosis patterns in experimental Taenia solium and Taenia crassiceps strobilae from golden hamsters.

    Science.gov (United States)

    Presas, Ana María Fernández; Robert, Lilia; Jiménez, José Agustín; Willms, Kaethe

    2005-04-01

    Apoptosis or programmed cell death (PCD) patterns of two taeniid species, Taenia solium and Taenia crassiceps, were explored in adult tapeworms grown in golden hamsters. Animals were fed either ten viable T. solium cysticerci from naturally infected pigs or from T. crassiceps WFU strain maintained in Balb/c mice. Adult strobilae were recovered from the intestine at different times after infection and either frozen at -70 degrees C or fixed in paraformaldehyde-glutaraldehyde. Frozen sections were processed using the DNA fragmentation fluorescent TUNEL reagents and examined in an epifluorescent microscope. Fixed tissues were processed for light and electron microscopy. Typical apoptotic cells were found in the central core of scolex and strobilar tissues, mainly in the germinal tissue and subtegumentary areas. By the TUNEL technique, cells exhibited the characteristic fluorescent images of condensed nuclear chromatin. By light microscopy of thick sections stained with toluidine blue, we found a number of small rounded cells which had lost their cytoplasmic bridges and had shrunken nuclei with aggregated chromatin, cells which were found interspersed with normal syncytial cells. Similar cell morphology was confirmed by electron microscopy. Stunted viable worms, recovered with longer mature specimens, had very short strobilae and exhibited a large number of apoptotic cells in the germinal neck tissues. The results are consistent with the syncytial nature of these parasites, and strongly suggest that cell proliferation and PCD in these adult cestodes are continuous processes of the germinal tissue and tegumentary cytons.

  15. A LigA three-domain region protects hamsters from lethal infection by Leptospira interrogans.

    Directory of Open Access Journals (Sweden)

    Mariana L Coutinho

    2011-12-01

    Full Text Available The leptospiral LigA protein consists of 13 bacterial immunoglobulin-like (Big domains and is the only purified recombinant subunit vaccine that has been demonstrated to protect against lethal challenge by a clinical isolate of Leptospira interrogans in the hamster model of leptospirosis. We determined the minimum number and location of LigA domains required for immunoprotection. Immunization with domains 11 and 12 was found to be required but insufficient for protection. Inclusion of a third domain, either 10 or 13, was required for 100% survival after intraperitoneal challenge with Leptospira interrogans serovar Copenhageni strain Fiocruz L1-130. As in previous studies, survivors had renal colonization; here, we quantitated the leptospiral burden by qPCR to be 1.2×10(3 to 8×10(5 copies of leptospiral DNA per microgram of kidney DNA. Although renal histopathology in survivors revealed tubulointerstitial changes indicating an inflammatory response to the infection, blood chemistry analysis indicated that renal function was normal. These studies define the Big domains of LigA that account for its vaccine efficacy and highlight the need for additional strategies to achieve sterilizing immunity to protect the mammalian host from leptospiral infection and its consequences.

  16. Respiratory tract tumors in Syrian hamsters following inhalation of Pu--ZrO2 particles

    International Nuclear Information System (INIS)

    Thomas, R.G.; Smith, D.M.

    1979-01-01

    Inhalation of radionuclide-bearing particles remains one of the most intensely pursued problems concerning the nuclear industry. This route of entry is generally accepted as the most probable, in case of human exposure, with ingestion being the other prominent source of concern. Many laboratory investigations, such as those reported here, continue to evaluate the possible consequences that may present health problems to the public domain. Syrian hamsters of both sexes received either inhaled (INH) PuO 2 /ZrO 2 particles, intravenous (IV) PuO 2 /ZrO 2 microspheres, a combination of INH PuO 2 /ZrO 2 particles and injected PuO 2 /ZrO 2 microspheres, or no radionuclides (controls). The INH particles and IV microspheres were tagged with γ-emitting 57 Co to facilitate whole body counting and establishment of retention curves. Total lung burdens ranged from 8 nCi to 143 nCi. Significant numbers of primary lung tumors (5 to 50% per group) were induced in those animals that received INH exposures. Additional α radiation administered via Pu-laden IV microspheres had little or no effect on tumor production or nonneoplastic, degenerative changes in the respiratory tract

  17. Arsenic in Ironite fertilizer: The absorption by hamsters and the chemical form

    Energy Technology Data Exchange (ETDEWEB)

    Aposhian, M.M.; Koch, I.; Avram, M.D.; Chowdhury, U.K.; Smith, P.G.; Reimer, K.J.; Aposhian, H.V.; (Ariz); (Royal)

    2009-09-11

    We determined the gastrointestinal absorption of the arsenic in Ironite, a readily available fertilizer, for male hamsters (Golden Syrian), considered to be an excellent model for how the human processes inorganic arsenic. Urine and feces were collected after administering an aqueous suspension of Ironite by stomach tube. In addition, we studied the forms and oxidation states of arsenic in Ironite by synchrotron spectroscopic techniques. The absorption of the arsenic in Ironite (1-0-0) was 21.2% and the absorption relative to sodium arsenite was 31.0%. Our results using XANES spectra determinations indicate that Ironite contains scorodite (AsV) as well as previously reported arsenopyrite (As(-1)). Since the 1-0-0 Ironite is readily available for purchase, its risk assessment for children by professionals is recommended. This is especially important because it is used to fertilize large areas of grass in playgrounds and parks where children play. The absorption of the arsenic in it, the hand to mouth activity of children, and the potential of ground water contamination makes the use of 1-0-0 Ironite as a fertilizer a potential environmental hazard.

  18. In vitro detection of prionemia in TSE-infected cervids and hamsters.

    Directory of Open Access Journals (Sweden)

    Alan M Elder

    Full Text Available Blood-borne transmission of infectious prions during the symptomatic and asymptomatic stages of disease occurs for both human and animal transmissible spongiform encephalopathies (TSEs. The geographical distribution of the cervid TSE, chronic wasting disease (CWD, continues to spread across North America and the prospective number of individuals harboring an asymptomatic infection of human variant Creutzfeldt-Jakob Disease (vCJD in the United Kingdom has been projected to be ~1 in 3000 residents. Thus, it is important to monitor cervid and human blood products to ensure herd health and human safety. Current methods for detecting blood-associated prions rely primarily upon bioassay in laboratory animals. While bioassay provides high sensitivity and specificity, it requires many months, animals, and it is costly. Here we report modification of the real time quaking-induced conversion (RT-QuIC assay to detect blood-borne prions in whole blood from prion-infected preclinical white-tailed deer, muntjac deer, and Syrian hamsters, attaining sensitivity of >90% while maintaining 100% specificity. Our results indicate that RT-QuIC methodology as modified can provide consistent and reliable detection of blood-borne prions in preclinical and symptomatic stages of two animal TSEs, offering promise for prionemia detection in other species, including humans.

  19. Transgenic Chinese hamster V79 cell lines which exhibit variable levels of gpt mutagenesis

    International Nuclear Information System (INIS)

    Klein, C.B.; Rossman, T.G.

    1990-01-01

    The Escherichia coli gpt gene coding for xanthine-guanine phosphoribosyl transferase has been stably transfected into HPRT - Chinese hamster V79 cells. Several gpt - cell lines have been established, which retain the sequence(s) even after long-term culture without selection for gpt. While spontaneous mutagenesis to gpt - occurs rather frequently for most cell lines, it cannot be correlated with either the number of plasmid integration sites or deletion of the plasmid sequence(s). One transgenic cell line (g12), which continuously maintains a low spontaneous mutation frequency was used in comparative mutagenesis studies with wild-type V79 cells (gpt vs. hprt). Alkylating agents such as N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and β-propiolactone (BPL) are shown to be equally toxic and mutagenic in both g12 and V79 cells. UV and X-rays are also equally toxic to both cell lines. The data presented here suggests that g12 cells may be useful to study mammalian mutagenesis by agents which yield limited response at the hprt locus

  20. Potentially lethal damage versus sublethal damage: independent repair processes in actively growing Chinese hamster cells

    International Nuclear Information System (INIS)

    Utsumi, H.; Elkind, M.M.

    1979-01-01

    Actively growing V79 Chinese hamster cells, treated with anisotonic phosphate-buffered saline (PBS) after x irradiation, are more sensitive than cells treated with isotonic PBS or cells promptly incubated with complete medium immediately after irradiation. The sensitization of irradiated cells results from hypotonic as well as hypertonic NaCl concentrations in PBS, is strongly dependent on both temperature and time, and is mainly due to an increase in the final slope of the single-dose survival curve. After two x-ray dose fractions, the net response of cells sensitized after each fraction by anisotonic post-treatment is similar to that obtained for isotonically treated cells and indicates that sublethal damage repair is not influenced by the enhanced expression of lethal damage. Independence of the repair of damage which is potentially lethal from the repair of damage which is sublethal is further suggested by the more rapid rate of the former compared to that of the latter. The proposal is advanced that the enhanced expression of damage which, after x irradiation, can be shown to be potentially lethal results from a destabilization of the structural relationship between DNA and the nuclear envelope, and/or DNA and the nuclear protein matrix, as a consequence of osmotic changes produced by anisotonic treatment

  1. Insulin secretion and glucose uptake by isolated islets of the hamster

    International Nuclear Information System (INIS)

    Dunbar, J.C.; McLaughlin, W.J.; Walsh, M.F.J.; Foa, P.P.

    1976-01-01

    Isolated pancreatic islets of normal hamsters were perfused either in a closed or in a open system. When the buffer was recirculated and the endogenous insulin was allowed to accumulate, the islets secreted significantly less insulin than when the system was open and the endogenous insulin was washed away. The addition of monocomponent insulin or of proinsulin to the perfusion buffer significantly decreased insulin secretion. The inhibitory action of proinsulin was significantly greater than that of monocomponent insulin. C peptide had no effect. When pancreatic islets were incubated in a fixed volume of stationary buffer containing unlabeled glucose (1.0 mg or 3.0 mg/ml) and glucose-U- 14 C (1.0 μC/ml), the amount of insulin secreted and the 14 CO 2 produced by each islet decreased progressively as the number of islets in the sample increased. Under these conditions, the concentration of insulin required to inhibit insulin secretion increased with the concentration of glucose in the medium. Proinsulin did not alter the incorporation of leucine-4.5- 3 H into total extractable insulin (insulin + proinsulin). Thus, insulin and proinsulin appear to inhibit insulin release, but not insulin synthesis. (orig.) [de

  2. Recommended protocol for the Syrian hamster embryo (SHE) cell transformation assay.

    Science.gov (United States)

    Maire, Marie-Aline; Pant, Kamala; Phrakonkham, Pascal; Poth, Albrecht; Schwind, Karl-Rainer; Rast, Claudine; Bruce, Shannon Wilson; Sly, Jamie E; Bohnenberger, Susanne; Kunkelmann, Thorsten; Schulz, Markus; Vasseur, Paule

    2012-04-11

    The Syrian hamster embryo (SHE) cell transformation assay (CTA) is a short-term in vitro assay recommended as an alternative method for testing the carcinogenic potential of chemicals. SHE cells are "normal" cells since they are diploid, genetically stable, non-tumourigenic, and have metabolic capabilities for the activation of some classes of carcinogens. The CTA, first developed in the 1960s by Berwald and Sachs (1963,1964) [3,4], is based on the change of the phenotypic feature of cell colonies expressing the first steps of the conversion of normal to neoplastic-like cells with oncogenic properties. Pienta et al. (1977) [22] developed a protocol using cryopreserved cells to enhance practicality of the assay and limit sources of variability. Several variants of the assay are currently in use, which mainly differ by the pH at which the assay is performed. We present here the common version of the SHE pH 6.7 CTA and SHE pH 7.0 CTA protocols used in the ECVAM (European Centre for the Validation of Alternative Methods) prevalidation study on CTA reported in this issue. It is recommended that this protocol, in combination with the photo catalogues presented in this issue, should be used in the future and serve as a basis for the development of the OECD test guideline. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Uptake of low density lipoproteins by the hamster lung. Interactions with capillary endothelium

    International Nuclear Information System (INIS)

    Nistor, A.; Simionescu, M.

    1986-01-01

    The mechanism by which the circulating low density lipoproteins (LDL) contribute to the lung surfactant cholesterol was investigated by perfusing the hamster lung in situ with LDL either radiolabeled or coupled to gold, or both. Part of [ 125 I]-LDL and [ 3 H]-cholesterol LDL were taken up by a specific process which was time- and concentration-dependent and reached saturation within 20 to 30 min of perfusion. Competition experiments and removal of receptor-bound LDL by heparin suggested that about 50% of LDL uptake is receptor-independent. Experiments using double labeled LDL showed a preferential uptake of 3 H-cholesterol versus 125 I by the lung both in situ and in vivo. LDL-gold particles (LDL-Au), recirculated through the isolated lung, bound to the endothelial luminal plasma membrane and to features potentially involved in receptor-mediated endocytosis (coated pits, coated vesicles, lysosomelike structures) and in transcytosis (plasmalemmal vesicles). The results suggest that LDL uptake by the lung takes place by both receptor-mediated and receptor-independent mechanisms. Cholesterol may be in part transferred to the lung without the apoprotein moiety; the alveolar capillary endothelium appears to be the first monitor of this complex process

  4. Genetic effects of the flavonols quercetin, kaempferol, and galangin on Chinese hamster ovary cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Carver, J.H. (Lawrence Livermore National Lab., Livermore, CA); Carrano, A.V.; MacGregor, J.T.

    1983-01-01

    The genotoxicity of selected flavonols was evaluated by multiple endpoints in Chinese hamster ovary (CHO) cells. Chromosomal aberrations, sister-chromatid exchange (SCE), and forward mutation at 4 gene loci were measured in a single population of cells exposed to quercetin, kaempferol, or galangin for 15 h with and without metabolic activation. The incidence of chromosomal aberrations was significantly increased by quercetin in the absence of activation and by kaempferol and galangin with and without activation. Flavanol treatment affected SCE and mutation at the hgprt, aprt, or Na/sup +//K/sup +/-ATPase loci only marginally, but significantly increased mutation frequencies at the tk locus. The response at the tk locus suggests that the CHO cells may behave similarly to L5178Y cells, in which the tk locus is thought to reflect chromosomal lesions in addition to point mutation. These results indicate that, at least under the conditions examined, flavonols induce chromosomal aberrations in CHO cells, but have little effect on point mutation or SCE.

  5. Expression of a human gene for polyamine transport in Chinese-hamster ovary cells.

    Science.gov (United States)

    Byers, T L; Wechter, R; Nuttall, M E; Pegg, A E

    1989-01-01

    A molecular-genetic approach towards isolating mammalian polyamine-transport genes and their encoded proteins was devised involving the production of Chinese-hamster ovary (CHO) cells expressing a human polyamine-transport protein. CHO cells and a polyamine-transport-deficient CHO mutant cell line (CHOMG) were equally sensitive to the antiproliferative effects of alpha-difluoromethylornithine (DFMO), which blocked endogenous polyamine synthesis. Exposure to exogenous polyamines increased intracellular polyamine levels and reversed this DFMO-induced cytostasis in the CHO cells, but not in the CHOMG cells. CHOMG cells were therefore transfected with human DNA (isolated from HT-29 colon carcinoma cells) and cells expressing the human polyamine-transport system were identified by the ability of these cells to grow in a medium containing DFMO and polyamines. A number of different positive clones were identified and shown to have the capacity for polyamine uptake and an increased sensitivity to the toxic effects of the polyamine analogue methylglyoxal bis(guanylhydrazone). Differences in these properties between the clones are consistent with a multiplicity of polyamine-transport systems. Some clones also showed a change in growth characteristics, which may indicate a relationship between genes involved in the polyamine-transport system and in cell proliferation. PMID:2512913

  6. The mutation studies of mutagen-sensitive and DNA repair mutants of Chinese hamster fibroblasts

    International Nuclear Information System (INIS)

    Schultz, R.A.; Chang, C.C.; Trosko, J.E.

    1981-01-01

    We have previously reported the isolation and partial characterization of DNA repair and/or mutagen-sensitive mutant Chinese hamster cell strains. Here we present the results of a detailed study of the ultraviolet light (UV)-induced mutability of one of these strains, UVs-7, and provide preliminary mutability data on two additional lines, UVr-23 and UVs-40. UVs-7 in extremely deficient in unscheduled DNA synthesis (UDS) but only slightly more sensitive to UV than the parental line. When examined for the UV-inducibility of mutants resistant to ouabain, 6-thioguanine, or diphtheria toxin, UVs-7 was found to be hypermutable at all three loci as compared to the parental line. The degree of hypermutability was not the same for any two loci. UVs-40, a highly UV-sensitive strain, was also found to be hypermutable at the ouabain-resistant (ouar) locus. UVr-23, which is UV-resistant and more proficient at UDS than the parental line, appeared to exhibit a tendency toward hypomutability at both the ouabain(ouar) and 6-thioguanine--resistant (6TGr) loci. Further characterization of all these lines should aid in delineating mammalian mechanisms of DNA repair and mutagenesis

  7. Caffeine-enhanced survival of radiation-sensitive, repair-deficient Chinese hamster cells

    International Nuclear Information System (INIS)

    Utsumi, H.; Elkind, M.M.

    1983-01-01

    A clone of V79 Chinese hamster cells (V79-AL162/S-10) with unique properties has been isolated after a challenge of parental cells (V79-AL162) with 1 mM ouabain. Compared with parental cells, or with other clones isolated after the ouabain challenge, these cells form smaller colonies, are more sensitive to both x rays and fission-spectrum neutrons, and respond atypically to a postirradiation treatment with caffeine. Their enhanced response to x rays results mainly from a large reduction in the shoulder of their survival curve, probably because in late S phase, the most resistant phase in the cell cycle, the survival curve of these cells has a reduced shoulder width. Caffeine, and to a lesser extent theophylline, added to the colony-forming medium immediately after exposure appreciably increases the width of the shoulder of these sensitive cells, whereas caffeine has the opposite effect on the response of normal V79 cells. Thus the unique response of the V79-AL162/S-10 cells to a radiation posttreatment with caffeine (increased survival) results from a net increase in their ability to repair damage that is otherwise lethal; caffeine treatment ordinarly prevents normal V79 cells from repairing damage that is only potentially lethal

  8. Radiation-induced mutagenicity in repair deficient Chinese hamster ovary (CHO) mutants

    International Nuclear Information System (INIS)

    Tesmer, J.G.; Saunders, E.H.; Chen, D.J.

    1987-01-01

    To determine if there is a relationship between DNA double-strand break repair and mutagenicity the authors utilized two x-ray sensitive mutants of Chinese hamster ovary cells along with the parental line K1. The two mutant lines xrs-5 and xrs-6, which have different DSB repair capabilities, were used to determine cell killing and 6-thioguanine resistance (6TG/sup r/) mutation frequencies induced by either x-rays of α-particles, x-ray survival data indicated the two mutant lines have similar sensitivity and are 5-7 fold more sensitive than the parental line K1. The mutant lines are also sensitive to α-particles but to a lesser extent. The authors' 6TG mutation data indicated that the two mutant lines are hypermutable. When mutation frequencies were plotted against the log of survival, mutation frequency at a given survival level was greater in mutant cell population than in parental K1 cells. Their results support the notion that repair of DSB play an important role in the expression of radiation-induced cell killing and mutagenicity

  9. Evidence for multiple repair pathways of double-strand DNA breaks in Chinese hamster cells

    International Nuclear Information System (INIS)

    Giaccia, A.J.; Weistein, R.; Stamato, T.D.; Roosa, R.

    1984-01-01

    XR-1 is a mutant of the Chinese hamster cell (CHO-K1) which is abnormally sensitive to killing by gamma rays in G/sub 1/ (D37 = 27 rads vs. 318 for parent) and early S phases of the cell cycle but has near normal resistance in late S and early G/sub 2/ (Somatic Cell Genetics, 9:165-173, 1983). Complementation studies between XR-1 and its parent indicate that this sensitivity to gamma rays is a recessive phenotype. Both the XR-1 and its parent cell are able to repair single strand DNA breaks. However, in comparison to its parental cell, the XR-1 cell is markedly deficient in the repair of double strand DNA breaks introduced by gamma irradiation during the sensitive G/sub 1/-early S period, while in the late S-G/sub 2/ resistant period the repair is similar in both cells. This correlation suggests that an unrepaired double strand DNA break is the lethal lesion and that at least two pathways for the repair of these lesions exist in mammalian cells

  10. Isolation and characterization of a radiosensitive Chinese hamster ovary cell line

    International Nuclear Information System (INIS)

    Fuller, L.F.

    1987-01-01

    A x-ray sensitive Chinese hamster ovary cell line was isolated using a semi-automated procedure in which mutagenized CHO cells were allowed to form colonies on top of agar, x-irradiated, then photographed at two later times. Comparison of the photographs allowed the identification of colonies which displayed significant growth arrest. One of the colonies identified in this manner produced a stable, radiosensitive line. This cell line is normal in x-ray induced inhibition of DNA synthesis, and single- and double-strand break repair, and is moderately sensitive to ethyl methane sulfonate and UV light. The sensitive line performs only half as much x-ray-induced repair replication as the parental line and this deficiency is believed to be the primary cause of its radiosensitivity. The sensitive line produces significantly higher numbers of x-ray-induced chromosome and chromatid aberrations including chromatid aberrations following exposure during the G 1 phase of the cell cycle. The line is hypomutable compared to the parental line with x-ray exposure inducing only one-third as many 6-thioguanine resistant colonies

  11. Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents

    International Nuclear Information System (INIS)

    Kaina, B.; Lohrer, H.; Karin, M.; Herrlich, P.

    1990-01-01

    Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of reduced glutathione synthesis, the transfectants were not more resistant to the lethal effects of ionizing radiation and bleomycin than the parent cells. Thus free radicals generated by these agents cannot be scavenged efficiently by MT in vivo. The hMT-IIA transfectants, however, but not control transfectants harboring a BPV-MT promoter-neo construct, tolerated significantly higher doses of the alkylating agents N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine. Resistance and MT overexpression occurred irrespective of selection and cultivation in cadmium and zinc. There was no increase in resistance to methyl methanesulfonate and N-hydroxyethyl-N-chloroethylnitrosourea. MT did not affect the degree of overall DNA methylation after N-methyl-N-nitrosourea treatment nor the level of O6-methylguanine-DNA methyltransferase. The results suggest that MT participates as a cofactor or regulatory element in repair or tolerance of toxic alkylation lesions

  12. Isolation of cell cycle-dependent gamma ray-sensitive Chinese hamster ovary cell

    International Nuclear Information System (INIS)

    Stamato, T.D.; Weinstein, R.; Giaccia, A.; Mackenzie, L.

    1983-01-01

    A technique for the isolation of gamma ray-sensitive Chinese hamster ovary (CHO) cell mutants is described, which uses nylon cloth replica plating and photography with dark-field illumination to directly monitor colonies for growth after gamma irradiation. Two gamma ray-sensitive mutants were isolated using this method. One of these cells (XR-1) had a two-slope survival curve: an initial steep slope and then a flattening of the curve at about 10% survival. Subsequently, it was found that this cell is sensitive to gamma irradiation in G1, early S, and late G2 phases of the cell cycle, whereas in the resistant phase (late S phase) its survival approaches that of the parental cells. The D37 in the sensitive G1 period is approximately 30 rads, compared with 300 rads of the parental cell. This mutant cell is also sensitive to killing by the DNA breaking agent, bleomycin, but is relatively insensitive to UV light and ethyl methane sulfonate, suggesting that the defect is specific for agents that produce DNA strand breakage

  13. Pygidiopsis cambodiensis n. sp. (Digenea: Heterophyidae) from experimental hamsters infected with metacercariae in mullets from Cambodia.

    Science.gov (United States)

    Sohn, Woon-Mok; Kim, Deok-Gyu; Jung, Bong-Kwang; Cho, Jaeeun; Chai, Jong-Yil

    2016-01-01

    Pygidiopsis cambodiensis n. sp. is described based on adult flukes recovered from Syrian golden hamsters experimentally infected with metacercariae from mullets (Liza macrolepis) purchased at a local fish market in Phnom Penh, Cambodia. The specimens were examined by light and scanning electron microscopy. Among the 13 species so far assigned to Pygidiopsis, the new species belongs to the summa-type (including Pygidiopsis pelecani, Pygidiopsis phalacrocoracis, Pygidiopsis piclaumoreli, Pygidiopsis plana, and Pygidiopsis summa) which lack circumoral spines and have vitelline follicles extending posteriorly from the level of the ovary some distance into the post-testicular space and the uterus not exceeding the acetabulum anteriorly. The new species differs from the other five species of the summa-type particularly in the morphology of the ventrogenital complex, including the genital sac, gonotyl, and gonotyl spines (= rodlets). The genital sac is well developed, sucker-like, slightly larger than the ventral sucker, muscular, and equipped with two gonotyls on the ventral side of the sac. Gonotyls are protruding pad-like, and the number of rodlets on the left gonotyl is four to five and that on the right gonotyl is 10-11 in two rows. This is the fifth Pygidiopsis species reported in Asia, following P. summa (Japan, Korea, and Vietnam), P. phalacrocorasis (Japan), P. pelecani (China), and Pygidiopsis marivillai (Philippines).

  14. Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents

    Energy Technology Data Exchange (ETDEWEB)

    Kaina, B.; Lohrer, H.; Karin, M.; Herrlich, P. (Kernforschungszentrum Karlsruhe, Karlsruhe (Germany, F.R.))

    1990-04-01

    Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of reduced glutathione synthesis, the transfectants were not more resistant to the lethal effects of ionizing radiation and bleomycin than the parent cells. Thus free radicals generated by these agents cannot be scavenged efficiently by MT in vivo. The hMT-IIA transfectants, however, but not control transfectants harboring a BPV-MT promoter-neo construct, tolerated significantly higher doses of the alkylating agents N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine. Resistance and MT overexpression occurred irrespective of selection and cultivation in cadmium and zinc. There was no increase in resistance to methyl methanesulfonate and N-hydroxyethyl-N-chloroethylnitrosourea. MT did not affect the degree of overall DNA methylation after N-methyl-N-nitrosourea treatment nor the level of O6-methylguanine-DNA methyltransferase. The results suggest that MT participates as a cofactor or regulatory element in repair or tolerance of toxic alkylation lesions.

  15. Overexpressed human metallothionein IIA gene protects Chinese hamster ovary cells from killing by alkylating agents.

    Science.gov (United States)

    Kaina, B; Lohrer, H; Karin, M; Herrlich, P

    1990-01-01

    Experiments were designed to detect survival advantages that cells gain by overexpressing metallothionein (MT). Chinese hamster ovary K1-2 cells and an x-ray-sensitive derivative were transfected with a bovine papillomavirus (BPV)-linked construct carrying the human metallothionein IIA (hMT-IIA) gene. Transfectants survived 40-fold higher levels of cadmium chloride, harbored at least 30 copies of hMT-IIA, and contained 25- to 166-fold more MT than the parent cells. Even under conditions of reduced glutathione synthesis, the transfectants were not more resistant to the lethal effects of ionizing radiation and bleomycin than the parent cells. Thus free radicals generated by these agents cannot be scavenged efficiently by MT in vivo. The hMT-IIA transfectants, however, but not control transfectants harboring a BPV-MT promoter-neo construct, tolerated significantly higher doses of the alkylating agents N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine. Resistance and MT overexpression occurred irrespective of selection and cultivation in cadmium and zinc. There was no increase in resistance to methyl methanesulfonate and N-hydroxyethyl-N-chloroethylnitrosourea. MT did not affect the degree of overall DNA methylation after N-methyl-N-nitrosourea treatment nor the level of O6-methylguanine-DNA methyltransferase. The results suggest that MT participates as a cofactor or regulatory element in repair or tolerance of toxic alkylation lesions. Images PMID:2320583

  16. ΔJunD overexpression in the nucleus accumbens prevents sexual reward in female Syrian hamsters.

    Science.gov (United States)

    Been, L E; Hedges, V L; Vialou, V; Nestler, E J; Meisel, R L

    2013-08-01

    Motivated behaviors, including sexual experience, activate the mesolimbic dopamine system and produce long-lasting molecular and structural changes in the nucleus accumbens. The transcription factor ΔFosB is hypothesized to partly mediate this experience-dependent plasticity. Previous research in our laboratory has demonstrated that overexpressing ΔFosB in the nucleus accumbens of female Syrian hamsters augments the ability of sexual experience to cause the formation of a conditioned place preference. It is unknown, however, whether ΔFosB-mediated transcription in the nucleus accumbens is required for the behavioral consequences of sexual reward. We therefore used an adeno-associated virus to overexpress ΔJunD, a dominant negative binding partner of ΔFosB that decreases ΔFosB-mediated transcription by competitively heterodimerizing with ΔFosB before binding at promotor regions on target genes, in the nucleus accumbens. We found that overexpression of ΔJunD prevented the formation of a conditioned place preference following repeated sexual experiences. These data, when coupled with our previous findings, suggest that ΔFosB is both necessary and sufficient for behavioral plasticity following sexual experience. Furthermore, these results contribute to an important and growing body of literature demonstrating the necessity of endogenous ΔFosB expression in the nucleus accumbens for adaptive responding to naturally rewarding stimuli. © 2013 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  17. A Consensus Genome-scale Reconstruction of Chinese Hamster Ovary Cell Metabolism

    KAUST Repository

    Hefzi, Hooman

    2016-11-23

    Chinese hamster ovary (CHO) cells dominate biotherapeutic protein production and are widely used in mammalian cell line engineering research. To elucidate metabolic bottlenecks in protein production and to guide cell engineering and bioprocess optimization, we reconstructed the metabolic pathways in CHO and associated them with >1,700 genes in the Cricetulus griseus genome. The genome-scale metabolic model based on this reconstruction, iCHO1766, and cell-line-specific models for CHO-K1, CHO-S, and CHO-DG44 cells provide the biochemical basis of growth and recombinant protein production. The models accurately predict growth phenotypes and known auxotrophies in CHO cells. With the models, we quantify the protein synthesis capacity of CHO cells and demonstrate that common bioprocess treatments, such as histone deacetylase inhibitors, inefficiently increase product yield. However, our simulations show that the metabolic resources in CHO are more than three times more efficiently utilized for growth or recombinant protein synthesis following targeted efforts to engineer the CHO secretory pathway. This model will further accelerate CHO cell engineering and help optimize bioprocesses.

  18. Effects of proliferation on the decay of thermotolerance in Chinese hamster cells.

    Science.gov (United States)

    Armour, E P; Li, G C; Hahn, G M

    1985-09-01

    Development and decay of thermotolerance were observed in Chinese hamster HA-1 cells. The thermotolerance kinetics of exponentially growing and fed plateau-phase cells were compared. Following a 10-min heat exposure at 45 degrees C, cells in both growth states had similar rates of development of tolerance to a subsequent 45-min exposure at 45 degrees C. This thermotolerant state started to decay between 12 and 24 hr after the initial heat exposure. The decay appeared to initiate slightly sooner in the exponentially growing cells when compared to the fed plateau-phase cells. During the decay phase, the rate of thermotolerance decay was similar in the two growth conditions. In other experiments, cells were induced to divide at a slower rate by chronic growth (3 months) in a low concentration of fetal calf serum. Under these low serum conditions cells became more sensitive to heat and the rate of decay of thermotolerance remained the same for exponentially growing cells. Plateau-phase cells were also more sensitive, but thermotolerance decayed more rapidly in these cells. Although dramatic cell cycle perturbations were seen in the exponentially growing cells, these changes appeared not to be related to thermotolerance kinetics.

  19. Influence of photoperiod and running wheel access on the entrainment of split circadian rhythms in hamsters

    Directory of Open Access Journals (Sweden)

    Elliott Jeffrey A

    2005-06-01

    Full Text Available Abstract Background In the laboratory, behavioral and physiological states of nocturnal rodents alternate, with a period near 24 h, between those appropriate for the night (e.g., elevated wheel-running activity and high melatonin secretion and for the day (e.g., rest and low melatonin secretion. Under appropriate 24 h light:dark:light:dark conditions, however, rodents may be readily induced to express bimodal rest/activity cycles that reflect a global temporal reorganization of the central neural pacemaker in the hypothalamus. We examine here how the relative length of the light and dark phases of the environmental cycle influences this rhythm splitting and the necessity of a running wheel for expression of this entrainment condition. Results Rhythm splitting was observed in wheel-running and general locomotion of Siberian and Syrian hamsters. The latter also manifest split rhythms in body temperature. Access to a running wheel was necessary neither for the induction nor maintenance of this entrainment pattern. While rhythms were only transiently split in many animals with two 5 h nights, the incidence of splitting was greater with twice daily nights of shorter duration. Removal of running wheels altered the body temperature rhythm but did not eliminate its clear bimodality. Conclusion The expression of entrained, split circadian rhythms exhibits no strict dependence on access to a running wheel, but can be facilitated by manipulation of ambient lighting conditions. These circadian entrainment patterns may be of therapeutic value to human shift-workers and others facing chronobiological challenges.

  20. Flow cytometric studies of the survival of cytochalasin-induced polyploidy in Chinese hamster ovary cells.

    Science.gov (United States)

    Court, J B; Burn, C; Moore, J L

    1990-05-01

    A method has been developed to estimate the post-irradiation survival of cytochalasin B-induced polyploidization of adherent Chinese hamster ovary cell using the flow cytometer. After exposure to radiation, surviving cells are allowed to become polyploid in the presence of cytochalasin, and are detached using trypsin, fixed by the addition of glutaraldehyde and stained using mithramycin. DNA content distributions are polymodal, and the absolute number of cells per culture in any given ploidy class is estimated by reference to a non-fluorescent bead internal standard, detected using forward scatter. Post-irradiation survival is defined as the ability to reach a given DNA content, and is reduced exponentially with dose. A bioassay to determine optimum cytochalasin concentrations can be derived from the relative size of the 2C (G0/G1) peak in the DNA content distribution. At culture densities greater than about 8 x 10(4) cell/cm2 the relative number of cells reaching at least 16C is reduced, but this inhibition is partially reversible by an increase in the medium glucose concentration, but not by the use of cytochalasin D or dihydro B.