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Sample records for hamster flank organ

  1. Effect of Saw Palmetto Supplements on Androgen-Sensitive LNCaP Human Prostate Cancer Cell Number and Syrian Hamster Flank Organ Growth

    Directory of Open Access Journals (Sweden)

    Alexander B. Opoku-Acheampong

    2016-01-01

    Full Text Available Saw palmetto supplements (SPS are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n=3; p<0.05. Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n=4, HLLP, HLHP, and HMLP SPS (n=6 groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p<0.05. Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth.

  2. Effect of Saw Palmetto Supplements on Androgen-Sensitive LNCaP Human Prostate Cancer Cell Number and Syrian Hamster Flank Organ Growth.

    Science.gov (United States)

    Opoku-Acheampong, Alexander B; Penugonda, Kavitha; Lindshield, Brian L

    2016-01-01

    Saw palmetto supplements (SPS) are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP) SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP) SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP) SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n = 3; p < 0.05). Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n = 4), HLLP, HLHP, and HMLP SPS (n = 6) groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p < 0.05). Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth.

  3. Selective induction of apoptosis in the hamster flank sebaceous gland organ by a topical liposome 5-alpha-reductase inhibitor: a treatment strategy for acne.

    Science.gov (United States)

    Li, Lingna; Tang, Li; Baranov, Eugene; Yang, Meng; Amoh, Yasuyuki; Katsuoka, Kensei; Hoffman, Robert M

    2010-02-01

    Acne is a very widespread cosmesis problem. Isotretinoin, a synthetic oral retinoid is used to treat acne, which is androgen dependent. Numerous side-effects occur from this treatment. 5-alpha-Reductase plays a critical role in normal and pathological androgen-dependent processes. We have taken the approach to develop a selective, effective, topically-applied 5-alpha-reductase inhibitor to modify unwanted or pathological processes in the pilosebaceous unit such as acne. Toward this goal, we have previously developed a selective liposome hair follicle targeting system. We demonstrate in this report that the 5-alpha-reductase inhibitor N,N-diethyl-4-methyl-3-oxo-4-aza-5alpha-androstane-17beta-carboxamide (4-MA) incorporated into liposomes induces apoptosis and inhibits growth of the dihydrotestosterone (DHT)-dependent hamster flank organ sebaceous gland. We have compared topical application of liposome 4-MA and solvent-formulated 4-MA and observed selective efficacy of topical application of liposome 4-MA by the reduction of size and induction of apoptosis only in the treated hamster flank organ. Apoptosis induced by liposome 4-MA in the treated flank organ sebaceous gland cells was observed both by assays for DNA fragments (transferase deoxytidyl uridine end labeling) and by observation of condensed and fragmented nuclei. When 4-MA was topically applied formulated in ethanol and glycerol without liposomes, the selective efficacy was lost. Liposome 4-MA did not significantly affect prostate weight, testosterone/DHT ratios or bodyweight gain compared to controls indicating safety as well as efficacy of topical application of liposome 4-MA for pathological processes such as acne.

  4. Vasopressin-dependent flank marking in golden hamsters is suppressed by drugs used in the treatment of obsessive-compulsive disorder

    Directory of Open Access Journals (Sweden)

    Messenger Tara

    2001-08-01

    Full Text Available Abstract Background Alterations in arginine vasopressin regulation and secretion have been proposed as one possible biochemical abnormality in patients with obsessive-compulsive disorder. In golden hamsters, arginine vasopressin microinjections into the anterior hypothalamus trigger robust grooming and flank marking, a stereotyped scent marking behaviors. The intensity and repetition of the behaviors induced by arginine vasopressin is somewhat reminiscent of Obsessive Compulsive Disorder in humans. The present experiments were carried out to test whether pharmacological agents used to alleviate obsessive compulsive disorder could inhibit arginine vasopressin-induced flank marking and grooming. Results Male golden hamsters were treated daily for two weeks with either vehicle, fluoxetine, clomipramine, or desipramine (an ineffective drug, before being tested for arginine vasopressin-induced flank marking and grooming. Flank marking was significantly inhibited in animals treated with fluoxetine or clomipramine but unaffected by treatment with desipramine. Grooming behavior was not affected by any treatment. Conclusion These data suggest that arginine vasopressin-induced flank marking may serve as an animal model for screening drugs used in the control of Obsessive Compulsive Disorder.

  5. 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.

  6. A rhodanine flanked nonfullerene acceptor for solution-processed organic photovoltaics

    KAUST Repository

    Holliday, Sarah

    2015-01-21

    A novel small molecule, FBR, bearing 3-ethylrhodanine flanking groups was synthesized as a nonfullerene electron acceptor for solution-processed bulk heterojunction organic photovoltaics (OPV). A straightforward synthesis route was employed, offering the potential for large scale preparation of this material. Inverted OPV devices employing poly(3-hexylthiophene) (P3HT) as the donor polymer and FBR as the acceptor gave power conversion efficiencies (PCE) up to 4.1%. Transient and steady state optical spectroscopies indicated efficient, ultrafast charge generation and efficient photocurrent generation from both donor and acceptor. Ultrafast transient absorption spectroscopy was used to investigate polaron generation efficiency as well as recombination dynamics. It was determined that the P3HT:FBR blend is highly intermixed, leading to increased charge generation relative to comparative devices with P3HT:PC60BM, but also faster recombination due to a nonideal morphology in which, in contrast to P3HT:PC60BM devices, the acceptor does not aggregate enough to create appropriate percolation pathways that prevent fast nongeminate recombination. Despite this nonoptimal morphology the P3HT:FBR devices exhibit better performance than P3HT:PC60BM devices, used as control, demonstrating that this acceptor shows great promise for further optimization.

  7. Djungarian hamsters ( Phodopus sungorus) are not susceptible to stimulating effects of 6-methoxy-2-benzoxazolinone on reproductive organs

    Science.gov (United States)

    Diedrich, Victoria; Scherbarth, Frank; Jähnig, Susanne; Kastens, Sabine; Steinlechner, Stephan

    2014-02-01

    The secondary plant metabolite 6-methoxy-2-benzoxazolinone (6-MBOA) is abundant in vegetative parts of monocotyledons emerging in spring. This grazing protective has been shown to promote gonadal growth and, thus enable precise alignment of reproductive activity with favorable environmental conditions in a variety of seasonally breeding rodent species. Feeding and breeding ecology make the Djungarian hamster ( Phodopus sungorus) a potential candidate using 6-MBOA as an acute environmental cue to optimize reproductive timing when photorefractoriness induces reproductive recrudescence. Therefore, four different experiments were designed to examine whether the hamsters' reproductive organs are responsive to oral 6-MBOA administration under different photoperiodic conditions. Only under a long photoperiod, we found a slight increase in uterine weights. In a short photoperiod, 6-MBOA-treated hamsters showed a slight body weight gain without a change in uterine weights. However, these marginal effects are likely not to be of ecophysiological significance for reproductive timing. The results are in agreement with the common view that the annual changes in photoperiod length are not only the predominant environmental cue for Djungarian hamsters, but are also sufficient to synchronize reproductive efforts with favorable breeding conditions in highly predictable climates like the continental Asian steppes.

  8. Structure-activity relationships of retinoids in hamster tracheal organ culture.

    Science.gov (United States)

    Newton, D L; Henderson, W R; Sporn, M B

    1980-10-01

    Structure-activity relationships are summarized for 87 retinoids, using reversal of keratinization in the hamster tracheal organ culture system to measure biological activity. Classes of compounds evaluated include all-trans-retinoic acid and its esters, ring-modified analogs of all-trans-retinoic acid and its esters, side-chain-modified analogs of all-trans-retinoic acid and its esters, analogs in which both ring and side chain have been modified, all-trans-retinol and derivatives, all-trans-retinyl amine derivatives, all-trans-retinal derivatives, all-trans-retinoic acid amides, 13-cis-retinoic acid and derivatives, and 5,6-epoxyretinoids. the activity of many synthetic amide derivatives of all-trans- or 13-cis-retinoic acid approaches that of the parent compounds. No metabolite of all-trans- or 13-cis-retinoic acid has yet been identified which has greater activity than the parent compounds in this assay. New synthetic derivatives with a gem-dimethyl group at position 4 in the cyclohexenyl ring and two aromatic rings in the side chain have activity equal to or greater than that of all-trans- or 13-cis-retinoic acid, with some activity detectable in the 10(-11) M range.

  9. 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

  10. Scanning electron microscopic study of hamster tracheal organ cultures infected with Bordetella pertussis.

    Science.gov (United States)

    Muse, K E; Collier, A M; Baseman, J B

    1977-12-01

    Hamster tracheal organculture was employed as a model for the study of the pathogenesis of infection due to bordetella pertusis. Scanning electron microscopy provided a three-dimensional view of the surface infection of the tracheal explants. Phase I B. pertussis attached only to the ciliated epithelial cells, and a sequence of events involving the injury, expulsion, and destruction of these differentiated cells occurred. This in vitro model provides insights into the mechanisms by which B. pertussis mediates host cell injury at the site of infection.

  11. Organization of amplified metallothionein (MT) genes in cadmium-resistant Chinese hamster cells

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrand, C.; Grady, D.; Meincke, L.; Clark, L.; Qui, X.; Fehrenbach, S.; Brown, N.; Jones, M.; Longmire, J.; Moyzis, R.

    1987-05-01

    In the parental, cadmium-sensitive, CHO cells, two MT genes (MT-I and II) have been cloned and shown to encompass approx.9 Kb of DNA. Both genes demonstrate the canonical intron-exon organization observed for other mammalian MT genes. Chromosome walking has been employed to study the organization of the MT genes in amplified cell lines. Using DNA from a highly-amplified cell line, Cd/sup r/ 200 T1, a genomic library was constructed in lambda Ch35 by standard procedures. Recombinants containing sequences complementary to a MT-II cDNA probe were isolated and characterized. Restriction enzyme analyses of these recombinants have extended the map of the MT-I and II gene region to encompass approx.35 Kb of DNA and indicate stability of the amplified genome over this region. A single SacII restriction site has been identified at the extreme 3' end of the cloned region. Since SacII is an infrequently-cutting restriction enzyme, accelerated long-range restriction mapping of the amplified MT gene region will be possible by combining chromosome walking in the MT gene region with large fragment separation using field-in-version gel electrophoresis.

  12. Adult sertoli cells are not terminally differentiated in the Djungarian hamster: effect of FSH on proliferation and junction protein organization.

    Science.gov (United States)

    Tarulli, Gerard A; Stanton, Peter G; Lerchl, Alexander; Meachem, Sarah J

    2006-05-01

    Sertoli cell number is considered to be stable and unmodifiable by hormones after puberty in mammals, although recent data using the seasonal breeding adult Djungarian hamster (Phodopus sungorus) model challenged this assertion by demonstrating a decrease in Sertoli cell number after gonadotropin depletion and a return to control levels following 7 days of FSH replacement. The present study aimed to determine whether adult Sertoli cells are terminally differentiated using known characteristics of cellular differentiation, including proliferation, junction protein localization, and expression of particular maturational markers, in the Djungarian hamster model. Adult long-day (LD) photoperiod (16L:8D) hamsters were exposed to short-day (SD) photoperiod (8L:16D) for 11 wk to suppress gonadotropins and then received exogenous FSH for up to 10 days. Sertoli cell proliferation was assessed by immunofluorescence by the colocalization of GATA4 and proliferating cell nuclear antigen and quantified by stereology. Markers of Sertoli cell maturation (immature, cytokeratin 18 [KRT18]; mature, GATA1) and junction proteins (actin, espin, claudin 11 [CLDN11], and tight junction protein 1 [TJP1, also known as ZO-1]) also were localized using confocal immunofluorescence. In response to FSH treatment, proliferation was upregulated within 2 days compared with SD controls (90% vs. 0.2%, P < 0.001) and declined gradually thereafter. In LD hamsters, junction proteins colocalized at the basal aspect of Sertoli cells, consistent with inter-Sertoli cell junctions, and were disordered within the Sertoli cell cytoplasm in SD animals. Exogenous FSH treatment promptly restored localization of these junction markers to the LD phenotype. Protein markers of maturity remain consistent with those of adult Sertoli cells. It is concluded that adult Sertoli cells are not terminally differentiated in the Djungarian hamster and that FSH plays an important role in governing the differentiation process. It

  13. Overleeft de hamster?

    NARCIS (Netherlands)

    Apeldoorn, van R.C.; Klein Douwel, C.; Thomas, P.

    1999-01-01

    Een analyse van de achteruitgang van de hamster (Cricetus cricetus) in Europa en Limburg, de oorzaken (veranderingen in de landbouw; versnippering van leefgebieden), en oplossingsrichtingen voor een duurzaam overleven van de hamster in Limburg (kernpopulaties in duurzame populatienetwerken)

  14. Characterization of the thermotropic behavior and lateral organization of lipid-peptide mixtures by a combined experimental and theoretical approach: Effects of hydrophobic mismatch and role of flanking residues

    DEFF Research Database (Denmark)

    Morein, S.; Killian, J.A.; Sperotto, Maria Maddalena

    2002-01-01

    A combined experimental and theoretical study was performed on a series of mixtures of dipalmitoylphosphatidylcholine (DPPC) and synthetic peptides to investigate their thermotropic behavior and lateral organization. The experimental study was based on differential scanning calorimetry (DSC...... bilayer hydrophobic thickness, and to investigate the potential role of flanking residues. The results show that both the WALP and the KALP peptides tend to favor the liquid-crystal line (or fluid) phase of the system; i.e., they tend to depress the main-transition temperature, T-m, of pure DPPC. However......, the detailed effects of both peptides on the lateral phase behavior of the lipid-peptide system are dependent on the peptide length and the type of flanking residues. The results suggest that below T-m, the shortest among the WALP and KALP peptides induce gel-fluid phase separation in the system within...

  15. A Thieno[2,3-b]pyridine-Flanked Diketopyrrolopyrrole Polymer as an n-Type Polymer Semiconductor for All-Polymer Solar Cells and Organic Field-Effect Transistors

    KAUST Repository

    Chen, Hung-Yang

    2017-12-28

    A novel fused heterocycle-flanked diketopyrrolopyrrole (DPP) monomer, thieno[2,3-b]pyridine diketopyrrolopyrrole (TPDPP), was designed and synthesized. When copolymerized with 3,4-difluorothiophene using Stille coupling polymerization, the new polymer pTPDPP-TF possesses a highly planar conjugated polymer backbone due to the fused thieno[2,3-b]pyridine flanking unit that effectively alleviates the steric hindrance with both the central DPP core and the 3,4-difluorothiophene repeat unit. This new polymer exhibits a high electron affinity (EA) of −4.1 eV and was successfully utilized as an n-type polymer semiconductor for applications in organic field-effect transistors (OFETs) and all polymer solar cells. A promising n-type charge carrier mobility of 0.1 cm2 V–1 s–1 was obtained in bottom-contact, top-gate OFETs, and a power conversion efficiency (PCE) of 2.72% with a high open-circuit voltage (VOC) of 1.04 V was achieved for all polymer solar cells using PTB7-Th as the polymer donor.

  16. Beschermingsplan hamster 2005-2010

    NARCIS (Netherlands)

    Haye, la M.J.J.; Jansman, H.A.H.

    2005-01-01

    Alterra-Concept van het beschermingsplan hamster 2005-2010. De hamster is in het meest westelijke deel van het Europese verspreidingsgebied bedreigd. De kennis die in de afgelopen periode is opgedaan van de hamster en de maatregelen die in het veld zijn uitgevoerd vormen de basis voor dit tweede

  17. Circadian rhythms accelerate wound healing in female Siberian hamsters.

    Science.gov (United States)

    Cable, Erin J; Onishi, Kenneth G; Prendergast, Brian J

    2017-03-15

    Circadian rhythms (CRs) provide temporal regulation and coordination of numerous physiological traits, including immune function. CRs in multiple aspects of immune function are impaired in rodents that have been rendered circadian-arrhythmic through various methods. In Siberian hamsters, circadian arrhythmia can be induced by disruptive light treatments (DPS). Here we examined CRs in wound healing, and the effects of circadian disruption on wound healing in DPS-arrhythmic hamsters. Circadian entrained/rhythmic (RHYTH) and behaviorally-arrhythmic (ARR) female hamsters were administered a cutaneous wound either 3h after light onset (ZT03) or 2h after dark onset (ZT18); wound size was quantified daily using image analyses. Among RHYTH hamsters, ZT03 wounds healed faster than ZT18 wounds, whereas in ARR hamsters, circadian phase did not affect wound healing. In addition, wounds healed slower in ARR hamsters. The results document a clear CR in wound healing, and indicate that the mere presence of organismal circadian organization enhances this aspect of immune function. Faster wound healing in CR-competent hamsters may be mediated by CR-driven coordination of the temporal order of mechanisms (inflammation, leukocyte trafficking, tissue remodeling) underlying cutaneous wound healing. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Gait Disturbances in Dystrophic Hamsters

    Directory of Open Access Journals (Sweden)

    Thomas G. Hampton

    2011-01-01

    Full Text Available The delta-sarcoglycan-deficient hamster is an excellent model to study muscular dystrophy. Gait disturbances, important clinically, have not been described in this animal model. We applied ventral plane videography (DigiGait to analyze gait in BIO TO-2 dystrophic and BIO F1B control hamsters walking on a transparent treadmill belt. Stride length was ~13% shorter (<.05 in TO-2 hamsters at 9 months of age compared to F1B hamsters. Hindlimb propulsion duration, an indicator of muscle strength, was shorter in 9-month-old TO-2 (247±8 ms compared to F1B hamsters (272±11 ms; <.05. Braking duration, reflecting generation of ground reaction forces, was delayed in 9-month-old TO-2 (147±6 ms compared to F1B hamsters (126±8 ms; <.05. Hindpaw eversion, evidence of muscle weakness, was greater in 9-month-old TO-2 than in F1B hamsters (17.7±1.2∘ versus 8.7±1.6∘; <.05. Incline and decline walking aggravated gait disturbances in TO-2 hamsters at 3 months of age. Several gait deficits were apparent in TO-2 hamsters at 1 month of age. Quantitative gait analysis demonstrates that dystrophic TO-2 hamsters recapitulate functional aspects of human muscular dystrophy. Early detection of gait abnormalities in a convenient animal model may accelerate the development of therapies for muscular dystrophy.

  19. Physiologic mastectomy via flank laparotomy.

    Science.gov (United States)

    Allen, Andrew J; Barrington, George M; Parish, Steve M

    2008-11-01

    Physiologic mastectomy can be used as a salvage procedure in cases of chronic suppurative mastitis, gangrenous mastitis, or chronic, severe mastitis associated with organisms liberating endotoxin or exotoxin. The surgical technique involves ligation of the major arterial blood supply (external pudendal artery) to the corresponding half of the mammary gland, which results in decreased systemic absorption of toxins and gland atrophy. The technique is performed with the cow standing, and it is relatively atraumatic. This procedure is a simple, yet effective alternative to radical mastectomy for unresponsive mastitis cases in genetically or otherwise valuable cattle.

  20. 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.

  1. ATTENUATION AND FLANKING TRANSMISSION IN LIGHTWEIGHT STRUCTURES

    DEFF Research Database (Denmark)

    Brunskog, Jonas; Lhomond, Alice; Ohlrich, Mogens

    2007-01-01

    In this paper the attenuation and flanking transmissions of impact noise in lightweight building structures is studied using a modal approach. The structural field is mainly analysed, putting the main attention to the parts being important in the modelling. The amount of attenuation produced...

  2. Lack of negative effects on Syrian hamsters and Mongolian gerbils housed in the same secondary enclosure.

    Science.gov (United States)

    Pritchett-Corning, Kathleen R; Gaskill, Brianna N

    2015-05-01

    In cases where different species might be housed in the same room or secondary enclosure, the Guide for the Care and Use of Laboratory Animals recommends that the animals should be behaviorally compatible and have the same health status. Syrian hamsters and Mongolian gerbils, both desert-dwelling rodents, appear to be reasonable candidates for such a combination. This study was undertaken to evaluate whether housing hamsters and gerbils in the same secondary enclosure is an acceptable practice. Weanling and breeding-age hamsters and gerbils were housed in open-topped cages in an isolator for 5 mo; the isolator also contained with nude and haired mice, which acted as sentinels. Cages housing hamsters and gerbils were rotated between species, and dirty bedding was exchanged between species in an effort to transmit microorganisms. In addition, sentinel mice housed in the isolator were supplied with dirty bedding from both hamsters and gerbils. Neither species showed clinical signs of illness, the health status of neither the hamsters nor the gerbils changed significantly, and the sentinel mice acquired only 2 infectious organisms, a Helicobacter species and Staphylococcus aureus. Both hamsters and gerbils bred successfully when housed together in the same isolator, and no infanticide or mortality was seen. Breeding performance did not differ between isolator breeding and barrier breeding. This study supports the housing of hamsters and gerbils in the same secondary enclosure.

  3. Volcano Flank Structures on Earth and Mars

    Science.gov (United States)

    van Wyk de Vries, B.; Byrne, P. K.; Mathieu, L.; Murray, J. B.; Troll, V. R.

    2007-12-01

    Shield volcanoes on Earth and Mars share common features, including calderas and pit crater chains. A set of structures present on the sides of several of the large shields on Mars are not regarded as having Earth analogues, however. Flank terraces are topographically subtle structures, characterised by a gentle convex profile and a distinctive "fish scale" imbricate distribution pattern. Magma chamber inflation, lithospheric flexure, flank relaxation, or gravitational slumping have been suggested as terrace formation mechanisms. Terraces on both Mars and Earth are clearly visible only in slope maps, and may thus escape visual detection in the field. We show that both Mauna Loa (Hawaii) and Etna (Sicily) display the same characteristic "fish scale" terrace pattern. This pattern delineates structures that we contend are terrestrial flank terraces. Heterogeneities in volcano geometry, due to buttressing or extension, result in terrace distributions that are not as evenly circumferential as those on Mars. Plan and cross-sectional profiles, however, parallel those of the Martian structures. These structures may also be present on Alayta (Ethiopia), Santa Cruz (Galapagos), and Tendürek Dagi (Turkey). Another type of structure, larger and steeper than flank terraces but sharing a similar plan-view morphology, is also present on Mauna Lau and Etna. These "flank bulges" appear to correlate with structures on Piton de la Fournaise (La Réunion), Cosiguina (Nicaragua), and Karthala (Comoros) on Earth, and Apollinaris Patera and Tharsis Tholus on Mars. Elsewhere (Paul K. Byrne et al., this volume) we argue that lithospheric flexure is a likely formation mechanism for Martian terraces. Flexure is active beneath Mauna Loa, and possibly under Etna, and so may also be responsible for terrestrial flank terraces. Scaled analogue models suggest that the larger flank bulges are due to magma intrusions derived from large chambers within these edifices. There is thus a strong

  4. Closed Internal Degloving of the Flank

    Science.gov (United States)

    Remy, Lindsay F.; Azurdia, Jacob; Fansa, Ashraf; Ebraheim, Nabil A.

    2017-01-01

    Originally described in 1853 by Dr. Morel-Lavellee, closed internal degloving injuries represent an important, although uncommon, source of morbidity in trauma patients. These injuries are typically the result of a shearing or crushing force that traumatically separates the skin and subcutaneous tissue from the underlying fat. This results in disruption of perforating blood vessels and lymphatics, leading to hematoma/seroma formation. We describe two cases in which industrial crush injuries resulted in lumbar transverse process fracture. Both patients developed closed degloving injuries of the flank. To the author’s knowledge, this is the first case series describing the occurrence of closed internal degloving injuries of the flank with transverse process fractures. We advise that a high level of suspicion for these lesions to occur with transverse spinal fractures should be maintained, as they may arise several years after initial injury. PMID:28913385

  5. Microbial life in ridge flank crustal fluids.

    Science.gov (United States)

    Huber, Julie A; Johnson, H Paul; Butterfield, David A; Baross, John A

    2006-01-01

    To determine the microbial community diversity within old oceanic crust, a novel sampling strategy was used to collect crustal fluids at Baby Bare Seamount, a 3.5 Ma old outcrop located in the north-east Pacific Ocean on the eastern flank of the Juan de Fuca Ridge. Stainless steel probes were driven directly into the igneous ocean crust to obtain samples of ridge flank crustal fluids. Genetic signatures and enrichment cultures of microorganisms demonstrate that these crustal fluids host a microbial community composed of species indigenous to the subseafloor, including anaerobic thermophiles, and species from other deep-sea habitats, such as seawater and sediments. Evidence using molecular techniques indicates the presence of a relatively small but active microbial population, dominated by bacteria. The microbial community diversity found in the crustal fluids may indicate habitat variability in old oceanic crust, with inputs of nutrients from seawater, sediment pore-water fluids and possibly hydrothermal sources. This report further supports the presence of an indigenous microbial community in ridge flank crustal fluids and advances our understanding of the potential physiological and phylogenetic diversity of this community.

  6. Imaging visceral leishmaniasis in real time with golden hamster model: Monitoring the parasite burden and hamster transcripts to further characterize the immunological responses of the host.

    Science.gov (United States)

    Rouault, Eline; Lecoeur, Hervé; Meriem, Asma Ben; Minoprio, Paola; Goyard, Sophie; Lang, Thierry

    2017-02-01

    Characterizing the clinical, immunological and parasitological features associated with visceral leishmaniasis is complex. It involves recording in real time and integrating quantitative multi-parametric data sets from parasite infected host tissues. Although several models have been used, hamsters are considered the bona fide experimental model for Leishmania donovani studies. To study visceral leishmaniasis in hamsters we generated virulent transgenic L. donovani that stably express a reporter luciferase protein. Two complementary methodologies were combined to follow the infectious process: in vivo imaging using luciferase-expressing Leishmania and real time RT-PCR to quantify both Leishmania and host transcripts. This approach allows us: i) to assess the clinical outcome of visceral leishmaniasis by individual monitoring of hamster weight, ii) to follow the parasite load in several organs by real time analysis of the bioluminescence in vivo and through real time quantitative PCR analysis of amastigote parasite transcript abundance ex vivo, iii) to evaluate the immunological responses triggered by the infection by quantifying hamster transcripts on the same samples and iv) to limit the number of hamsters selected for further analysis. The overall data highlight a correlation between the transcriptional cytokine signatures of hamster affected tissues and the amastigote burden fluctuations, thus providing new insights into the immunopathological process driven by L. donovani in the tissues of mammalian hosts. Finally, they suggest organ-specific immune responses. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. New Sensitive Serum Melatonin Radioimmunoassay Employing the Kennaway G280 Antibody: Syrian Hamster Morning Adrenergic Response,

    Science.gov (United States)

    1993-01-01

    JORDAN, G. with Animal Welfare Act and other Federal statutes SASSOLAS (1984) A chronological study of melatonin and cortisol secretion in depressed...after a single aqueous subcutaneous injec- dian organization of cortisol and melatonin rhythms during tion in Syrian hamsters. Neuroendocrinoiogy 42:124...serum melatonin radioimmunoassay George M. Vaughan employing the Kennaway G280 antibody: Syrian hamster morning u.S. Army Institute of Surgical

  8. Diaphragm Structure and Function in Emphysematous Hamsters

    OpenAIRE

    Reid WD; RK Wilton

    1994-01-01

    OBJECTIVE: To determine if muscle fibre injury, reduced force output and fatigue of the diaphragm accompanied hyperinflation induced by experimental emphysema.DESIGN: Controlled and randomized.ANIMALS: Adult male golden Syrian hamsters: seven control and seven experimental emphysema hamsters were studied.INTERVENTIONS: Following anesthesia, experimental emphysema hamsters received a transtracheal injection of elastase. They also received injections of β-aminopropionitrile every other day for ...

  9. 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.

  10. Seasonal aspects of sleep in the Djungarian hamster.

    Science.gov (United States)

    Palchykova, Svitlana; Deboer, Tom; Tobler, Irene

    2003-05-19

    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. 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. 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.

  11. Different effects of inorganic and dimethylated arsenic compounds on cell morphology, cytoskeletal organization, and DNA synthesis in cultured Chinese hamster V79 cells.

    Science.gov (United States)

    Ochi, T; Nakajima, F; Fukumori, N

    1998-09-01

    Changes in cytoskeletal organization of cultured V79 cells exposed to arsenite and dimethylarsinic acid (DMAA), a methylated derivative of inorganic arsenics, and related changes, such as mitotic arrest and induction of multinucleated cells, were investigated in comparison with their effects on DNA synthesis. DMAA caused mitotic arrest and induction of multinucleated cells with a delay of 12 h relative to the mitotic arrest. By contrast, arsenite at equitoxic concentrations to DMAA was less effective than DMAA in causing mitotic arrest and in inducing multinucleated cells. Post-mitotic incubation of cells arrested in metaphase by 6 h incubation with 10 mM DMAA showed that the incidence of multinucleated cells increased conversely with a rapid decrease in metaphase cells. This suggests that metaphase-arrested cells can escape from metaphase, resulting in the appearance of multinucleated cells. The mitotic arrest caused by DMAA was accompanied by disruption of the microtubule network. By contrast, both arsenite and DMAA did not cause disorganization of actin stress fibers even when incubated at concentrations that caused a marked retardation of cell growth. Cells exposed to arsenite for 6 h showed marked inhibition of DNA synthesis, whereas inhibition by DMAA was not observed. When incubation was prolonged by 18 h, the arsenite-induced inhibition of DNA synthesis was mitigated. By contrast, inhibition of DNA synthesis by DMAA occurred in parallel with an increase in the population of mitotic cells. These results suggest that DMAA caused growth retardation and morphological changes via disruption of the microtubule network, and that arsenite-induced retardation of cell growth and inhibition of DNA synthesis were not attributable to the cytoskeletal changes.

  12. Different effects of inorganic and dimethylated arsenic compounds on cell morphology, cytoskeletal organization, and DNA synthesis in cultured Chinese hamster V79 cells

    Energy Technology Data Exchange (ETDEWEB)

    Ochi, Takafumi; Nakajima, Fumie [Department of Environmental Toxicology, Faculty of Pharmaceutical Sciences, Teikyo University, Sagamiko, Kanagawa (Japan); Fukumori, Nobutaka [Department of Toxicology, Tokyo Metropolitan Research Laboratory of Public Health, Hyakuninchou, Shinjyuku (Japan)

    1998-09-01

    Changes in cytoskeletal organization of cultured V79 cells exposed to arsenite and dimethylarsinic acid (DMAA), a methylated derivative of inorganic arsenics, and related changes, such as mitotic arrest and induction of multinucleated cells, were investigated in comparison with their effects on DNA synthesis. DMAA caused mitotic arrest and induction of multinucleated cells with a delay of 12 h relative to the mitotic arrest. By contrast, arsenite at equitoxic concentrations to DMAA was less effective than DMAA in causing mitotic arrest and in inducing multinucleated cells. Post-mitotic incubation of cells arrested in metaphase by 6 h incubation with 10 mM DMAA showed that the incidence of multinucleated cells increased conversely with a rapid decrease in metaphase cells. This suggests that metaphase-arrested cells can escape from metaphase, resulting in the appearance of multinucleated cells. The mitotic arrest caused by DMAA was accompanied by disruption of the microtubule network. By contrast, both arsenite and DMAA did not cause disorganization of actin stress fibers even when incubated at concentrations that caused a marked retardation of cell growth. Cells exposed to arsenite for 6 h showed marked inhibition of DNA synthesis, whereas inhibition by DMAA was not observed. When incubation was prolonged by 18 h, the arsenite-induced inhibition of DNA synthesis was mitigated. By contrast, inhibition of DNA synthesis by DMAA occurred in parallel with an increase in the population of mitotic cells. These results suggest that DMAA caused growth retardation and morphological changes via disruption of the microtubule network, and that arsenite-induced retardation of cell growth and inhibition of DNA synthesis were not attributable to the cytoskeletal changes. (orig.) (orig.) With 7 figs., 31 refs.

  13. Right psoas abscess following right flank trauma: a case report ...

    African Journals Online (AJOL)

    This is a case of 15 year old boy who presented with three weeks history of right flank pain, two weeks history of fever and five days history of inability to walk well. There was history of right flank trauma a week before the onset of right flank pain. He had earlier presented in two different hospitals before he was brought to our ...

  14. Hybridization capture using short PCR products enriches small genomes by capturing flanking sequences (CapFlank.

    Directory of Open Access Journals (Sweden)

    Kyriakos Tsangaras

    Full Text Available Solution hybridization capture methods utilize biotinylated oligonucleotides as baits to enrich homologous sequences from next generation sequencing (NGS libraries. Coupled with NGS, the method generates kilo to gigabases of high confidence consensus targeted sequence. However, in many experiments, a non-negligible fraction of the resulting sequence reads are not homologous to the bait. We demonstrate that during capture, the bait-hybridized library molecules add additional flanking library sequences iteratively, such that baits limited to targeting relatively short regions (e.g. few hundred nucleotides can result in enrichment across entire mitochondrial and bacterial genomes. Our findings suggest that some of the off-target sequences derived in capture experiments are non-randomly enriched, and that CapFlank will facilitate targeted enrichment of large contiguous sequences with minimal prior target sequence information.

  15. Directed Student Inquiry: Modeling in Roborovsky Hamsters

    Science.gov (United States)

    Elwess, Nancy L.; Bouchard, Adam

    2007-01-01

    In this inquiry-based activity, Roborovsky hamsters are used to provide students with an opportunity to develop their skills of analysis, inquiry, and design. These hamsters are easy to maintain, yet offer students a means to use conventional techniques and those of their own design to make further observations through measuring, assessing, and…

  16. Immunomodulatory treatment with thalidomide in experimental leptospirosis in Golden Syrian hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Soares, Luciane Marieta; Macedo, Julio Oliveira; de Azevedo, Everton Cruz; Santos, Cleiton Silva; Sampaio, Marina de Queiroz; dos Santos, Andréia Carvalho; dos Reis, Mitermayer Galvão; Athanazio, Daniel Abensur

    2014-02-01

    The benefit of antibiotics in leptospirosis is limited when treatment is started four days after symptoms appear, and new adjuvant therapeutic options are urgently needed. Hamsters (Mesocricetus auratus) were infected by Leptospira interrogans strain L1-130, and groups were assigned based on no treatment (NONE), thalidomide only (TAL), ampicillin only (AMP) or both (AMP-TAL). Treatment was started two days after the onset of symptoms (experiment 1) and immediately after detection of the first death (experiment 2). Experiment 1: all hamsters from the groups AMP and AMP-TAL survived (n=8), while all hamsters from groups NONE (n=6) and TAL (n=8) died. The AMP and the AMP-TAL groups showed no renal or liver pathology and absent or very low leptospiral burden in target organs. Experiment 2: lethal outcome was observed in 6/6 hamsters in the NONE group, 8/8 in the TAL group, and 6/8 in both the AMP and AMP-TAL groups. Thalidomide showed no survival benefit when compared to hamsters treated with ampicillin alone. The TAL, AMP and AMP-TAL groups had very low tissue leptospiral counts. Thalidomide had minimal impact on survival in the late treatment of leptospirosis hamster model.

  17. Cloning and characterization of corticotropin-releasing factor and urocortin in Syrian hamster (Mesocricetus auratus).

    Science.gov (United States)

    Robinson, B M; Tellam, D J; Smart, D; Mohammad, Y N; Brennand, J; Rivier, J E; Lovejoy, D A

    1999-01-01

    Corticotropin-releasing factor and urocortin belong to a superfamily of neuropeptides that includes the urotensins-I in fishes and the insect diuretic peptides. Sequence analysis suggests that urocortin is the mammalian ortholog of urotensin-I, although the physiological role for this peptide in mammals is not known. Within the Rodentia, hamsters belong to a phylogenetically older lineage than that of mice and rats and possess significant differences in hypothalamic organization. We have, therefore, cloned the coding region of the Syrian hamster (Mesocricetus auratus) corticotropin-releasing factor and urocortin mature peptide by polymerase chain reaction. Hamster urocortin was prepared by solid-phase synthesis, and its pharmacological actions on human corticotropin-releasing factor R1 and R2 receptors were investigated. The deduced hamster corticotropin-releasing factor amino acid sequence and cleavage site is identical to that in rat, whereas the urocortin sequence is unique among the urocortin/urotensin-I/sauvagine family in possessing asparagine and alanine in positions 38 and 39, respectively. The hamster urocortin carboxy terminus sequence bears greater structural similarity to the insect diuretic peptide family, suggesting either retrogressive mutational changes within the mature peptide or convergent sequence evolution. Despite these changes, human and hamster urocortin are generally equipotent at cAMP activation, neuronal acidification rate, and R1/R2 receptor affinities.

  18. Phase resetting in duper hamsters: specificity to photic zeitgebers and circadian phase.

    Science.gov (United States)

    Manoogian, Emily N C; Leise, Tanya L; Bittman, Eric L

    2015-04-01

    The duper mutation in Syrian hamsters shortens the free-running period of locomotor activity (τDD) to about 23 h and results in a type 0 phase-response curve (PRC) to 15-min light pulses. To determine whether exaggerated phase shifts are specific to photic cues and/or restricted to subjective night, we subjected hamsters to novel wheel confinements and dark pulses during subjective day. Small phase shifts elicited by the nonphotic cue were comparable in mutant and wild-type (WT) hamsters, but dark pulses triggered larger shifts in dupers. To assess further the effects of the duper mutation on light-dark transitions, we transferred hamsters between constant light (LL) and constant dark (DD) or between DD and LL at various circadian phases. Duper hamsters displayed significantly larger phase shifts than WT hamsters when transferred from LL to DD during subjective day and from DD to LL during subjective night. The variability of phase shifts in response to all light/dark transitions was significantly greater in duper hamsters at all time points. In addition, most duper hamsters, but none of the WTs, displayed transient ultradian wheel-running patterns for 5 to 12 days when transferred from light to dark at CT 18. The χ(2) periodogram and autocorrelation analyses indicate that these ultradian patterns differ from the disruption of rhythmicity by SCN lesions or exposure to constant bright light. We conclude that the duper mutation specifically amplifies phase shifts to photic cues and may destabilize coupling of circadian organization upon photic challenge due to weakened coupling among components of the circadian pacemaker. Mathematical modeling of the circadian pacemaker supports this hypothesis. © 2015 The Author(s).

  19. Flank pain: is Intravenous Urogram necessary?

    Science.gov (United States)

    Teh, H S; Lin, M B; Khoo, T K

    2001-09-01

    To determine the diagnostic yield of Intravenous Urogram (IVU) and the values of plain radiograph of kidney, ureter and bladder (KUB) and urinalysis as screening tests, with the objective to improve the cost effectiveness, in the management of patients presenting with flank pain due to urinary lithiasis. All Intravenous Urogram (IVU) request forms and reports for the month of February 1998 were audited. The case notes, urinalysis, KUB and IVU films were traced and reviewed. There were 110 patients investigated, 61.8% (68) had normal IVU, 38.2% (42) had abnormal IVU. The sensitivity and specificity of KUB alone was 79.4% and 90%. The sensitivity using urinalysis alone was 90.9% and its specificity 33.8%. The sensitivity of combined KUB and urinalysis was 100% and its specificity 26%, with a negative predictive value of 100%. All the patients with both negative KUB and urinalysis in our study were found to have negative IVU. Our study shows that in patients with both negative KUB and urinalysis, the yield of IVU is very low and may not be necessary. This is important, as an IVU examination is not without risk. A combination of KUB with urinary analysis and careful evaluation of clinical symptoms will improve the cost-effectiveness of patient management.

  20. 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.

  1. Effect of flanking sounds on the auditory continuity illusion.

    Directory of Open Access Journals (Sweden)

    Maori Kobayashi

    Full Text Available BACKGROUND: The auditory continuity illusion or the perceptual restoration of a target sound briefly interrupted by an extraneous sound has been shown to depend on masking. However, little is known about factors other than masking. METHODOLOGY/PRINCIPAL FINDINGS: We examined whether a sequence of flanking transient sounds affects the apparent continuity of a target tone alternated with a bandpass noise at regular intervals. The flanking sounds significantly increased the limit of perceiving apparent continuity in terms of the maximum target level at a fixed noise level, irrespective of the frequency separation between the target and flanking sounds: the flanking sounds enhanced the continuity illusion. This effect was dependent on the temporal relationship between the flanking sounds and noise bursts. CONCLUSIONS/SIGNIFICANCE: The spectrotemporal characteristics of the enhancement effect suggest that a mechanism to compensate for exogenous attentional distraction may contribute to the continuity illusion.

  2. Immunization and challenge shown by hamsters infected with Opisthorchis viverrini following exposure to gamma-irradiated metacercariae of this carcinogenic liver fluke.

    Science.gov (United States)

    Papatpremsiri, A; Junpue, P; Loukas, A; Brindley, P J; Bethony, J M; Sripa, B; Laha, T

    2016-01-01

    Here we report findings to optimize and standardize conditions to attenuate metacercariae of Opisthorchis viverrini by ionizing radiation to elicit protective immune responses to challenge infection. Metacercariae were gamma-irradiated and the ability of irradiated metacercariae to prevent patent infection of challenge metacercariae in hamsters was determined, as well as their ability to induce a host antibody response. Metacercariae irradiated in a dose-dependent manner, with 3, 5, 10, 12, 20, 25 and 50 Gray, were used to infect Syrian golden hamsters by stomach gavage to ascertain the effect of irradiation on ability of the worms to establish infection. In addition, other hamsters were infected with metacercariae irradiated with 20-50 Gray, followed by challenge with intact/wild-type (non-irradiated) metacercariae to determine the protective effect as established by the numbers of adult flukes, eggs of O. viverrini in hamster faeces and anti-O. viverrini antibody titres. Significantly fewer worms were recovered from hamsters immunized with metacercariae irradiated at 20, 25 and 50 Gray than from control hamsters infected with intact metacercariae or 0 Gray, and the worms showed damaged reproductive organs. Faecal egg numbers were decreased significantly in hamsters immunized with 25 and 50 Gray metacercariae of O. viverrini. Moreover, hamsters administered metacercariae that were protected elicited a robust, specific anti-fluke immunoglobulin G response compared to control hamsters, suggesting a role for antibody in protection elicited by radiation-attenuated metacercariae.

  3. 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.

  4. 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.

  5. 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...

  6. High virulence in hamsters of four dominant Leptospira serovars isolated from rats in the Philippines.

    Science.gov (United States)

    Villanueva, Sharon Y A M; Saito, Mitsumasa; Tsutsumi, Yutaka; Segawa, Takaya; Baterna, Rubelia A; Chakraborty, Antara; Asoh, Tatsuma; Miyahara, Satoshi; Yanagihara, Yasutake; Cavinta, Lolita L; Gloriani, Nina G; Yoshida, Shin-ichi

    2014-02-01

    Leptospirosis is caused by pathogenic species of Leptospira. The aim of this study was to determine and characterize the pathogenicity of four dominant Leptospira isolates prevailing among rats in the Philippines. The isolates were Leptospira interrogans serovar Manilae strain K64, L. interrogans serovar Losbanos strain K37, L. interrogans serovar Ratnapura strain K5 and Leptospira borgpetersenii serovar Javanica strain K6. Pathogenicities were studied using hamsters, which reproduce severe human leptospirosis. The minimum lethal doses were 10(0) ( = 1) leptospires for K64, K37 and K5, and 10(1) leptospires for K6. Weight loss amongst the Leptospira-infected hamsters was observed from 1 day before death (K64-, K37- and K5-infected hamsters) to as much as 1 week before death for K6-infected hamsters. Similar and varied gross and microscopic lesions were observed amongst infected hamsters, even for strains belonging to the same species (i.e. L. interrogans). The most significant and common histopathological findings were congestion of the glomerulus, disarrangement of hepatic cords and erythrophagocytosis. Other findings were foamy splenic macrophages for K6, severe petechial pulmonary haemorrhage for K64, and hematuria and severe pulmonary congestion for K37. Immunostaining and culture revealed the presence of leptospires in different organs of the infected hamsters. Based on these results, Leptospira isolates from rats in the Philippines were shown to be highly virulent, causing pulmonary haemorrhage, severe hepato-renal damage and death in hamsters even at lower doses. The present findings on experimental leptospirosis support clinical data showing that patients with severe manifestations of leptospirosis, such as pulmonary haemorrhage, are increasing in the Philippines. These findings may serve as a basis to strengthen the early diagnosis and treatment of human leptospirosis.

  7. Lethal disease in infant and juvenile Syrian hamsters experimentally infected with Imjin virus, a newfound crocidurine shrew-borne hantavirus.

    Science.gov (United States)

    Gu, Se Hun; Kim, Young-Sik; Baek, Luck Ju; Kurata, Takeshi; Yanagihara, Richard; Song, Jin-Won

    2015-12-01

    To gain insights into the pathogenicity of Imjin virus (MJNV), a newfound hantavirus isolated from the Ussuri white-toothed shrew (Crocidura lasiura), groups of Syrian hamsters (Mesocricetus auratus) of varying ages (hamsters, aged 21 days or less, exhibited reduced activity, weight loss, respiratory distress, hind-limb paralysis and seizures. Death ensued 1 to 6 days after onset of clinical disease. MJNV RNA was detected in brain and other major organs by RT-PCR and real time-PCR. Histopathological examination showed alveolar hemorrhage, interstitial pneumonia and severe pulmonary congestion; focal hepatic necrosis and portal inflammation; and acute meningoencephalitis. By immunohistochemistry, MJNV antigen was detected in pulmonary microvascular endothelial cells and glial cells. Older hamsters (35 and 56 days of age) developed subclinical infection without histopathological changes. Future studies are warranted to determine the pathophysiologic bases for the differential age susceptibility of Syrian hamsters to lethal MJNV disease. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Hibernation patterns of Turkish hamsters: influence of sex and ambient temperature.

    Science.gov (United States)

    Batavia, Mariska; Nguyen, George; Harman, Kristine; Zucker, Irving

    2013-02-01

    Turkish hamsters (Mesocricetus brandti) are a model organism for studies of hibernation, yet a detailed account of their torpor characteristics has not been undertaken. This study employed continuous telemetric monitoring of body temperature (T(b)) in hibernating male and female Turkish hamsters at ambient temperatures (T(a)s) of 5 and 13 °C to precisely characterize torpor bout depth, duration, and frequency, as well as rates of entry into and arousal from torpor. Hamsters generated brief intervals of short ( 20 °C), followed by deep torpor bouts lasting 4-6 days at T(a) = 5 °C and 2-3 days at T(a) = 13 °C. Females at T(a) = 5 °C had longer bouts than males, but maintained higher torpor T(b); there were no sex differences at T(a) = 13 °C. Neither body mass loss nor food intake differed between the two T(a)s. Hamsters entered torpor primarily during the scotophase (subjective night), but timing of arousals was highly variable. Hamsters at both T (a)s generated short, shallow torpor bouts between deep bouts, suggesting that this species may be capable of both hibernation and daily torpor.

  9. Submarine geology of Hana Ridge and Haleakala Volcano's northeast flank, Maui

    Science.gov (United States)

    Eakins, Barry W.; Robinson, Joel E.

    2006-01-01

    We present a morphostructural analysis of the submarine portions of Haleakala Volcano and environs, based upon a 4-year program of geophysical surveys and submersible explorations of the underwater flanks of Hawaiian volcanoes that was conducted by numerous academic and governmental research organizations in Japan and the U.S. and funded primarily by the Japan Agency for Marine–Earth Science and Technology. A resulting reconnaissance geologic map features the 135-km-long Hana Ridge, the 3000 km2 Hana slump on the volcano's northeast flank, and island-surrounding terraces that are the submerged parts of volcanic shields. Hana Ridge below 2000 m water depth exhibits the lobate morphology typical of the subaqueously erupted parts of Hawaiian rift zones, with some important distinctions: namely, subparallel crestlines, which we propose result from the down-rift migration of offsets in the dike intrusion zone, and an amphitheater at its distal toe, where a submarine landslide has embayed the ridge tip. Deformation of Haleakala's northeast flank is limited to that part identified as the Hana slump, which lies downslope from the volcano's submerged shield, indicating that flank mobility is also limited in plan, inconsistent with hypothesized volcanic spreading driven by rift-zone dilation. The leading edge of the slump has transverse basins and ridges that resemble the thrust ramps of accretionary prisms, and we present a model to describe the slump's development that emphasizes the role of coastally generated fragmental basalt on gravitational instability of Haleakala's northeast flank and that may be broadly applicable to other ocean-island slumps.

  10. Role of macrophages in host defense against hepatic amoebiasis in hamsters.

    Science.gov (United States)

    Ghadirian, E; Meerovitch, E; Kongshavn, P A

    1983-01-01

    The role of macrophages in hepatic amoebiasis in hamsters has been investigated by means of antimacrophage serum prepared in rabbits. Animals treated with normal rabbit serum or antimacrophage serum, as well as untreated controls, were inoculated intrahepatically with 10(5) axenic trophozoites of Entamoeba histolytica. In hamsters treated with antimacrophage serum before intrahepatic inoculation of amoebae, the mean weight of the metastatic foci was significantly greater than in normal rabbit serum-treated or untreated controls. Treatment of hamsters with antimacrophage serum both before and after administration of amoebae not only increased significantly the size of the abscess in the liver but also allowed dissemination of metastatic foci to other organs. PMID:6642657

  11. 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

  12. Pulmonary toxicity in hamsters of smoke particles from Kuwaiti oil fires.

    OpenAIRE

    Wolfthal, S F; Dumyahn, T; Brain, Joseph David; Long, N. C.; Dockery, Douglas W.

    1998-01-01

    The Kuwaiti oil wells set on fire by retreating Iraqi troops at the end of the Persian Gulf War released complex particles, inorganic and organic gases, and hydrocarbons into the atmosphere, damaging the environment where many people live and work. In this study, we assessed the health effects of particles from the Kuwaiti oil fires by instilling hamsters intratracheally with particles (

  13. 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...

  14. Enteritis caused by Pasteurella pneumotropica infection in hamsters.

    OpenAIRE

    Lesher, R J; Jeszenka, E V; Swan, M E

    1985-01-01

    Pasteurella pneumotropica was isolated in essentially pure cultures from the bowels of hamsters with enteritis 7 days after parturition. Newly received hamsters showed presence of P. pneumotropica in their nasal cavities but not in their uteri, lungs, spleens, or bowels.

  15. Strain-Specific Barriers against Bovine Prions in Hamsters

    OpenAIRE

    Nicot, Simon; Baron, Thierry

    2010-01-01

    We investigated the susceptibilities of Syrian golden hamsters to transmissible spongiform encephalopathy agents from cattle. We report efficient transmission of the L-type atypical bovine spongiform encephalopathy (BSE) agent into hamsters. Importantly, hamsters were also susceptible to the transmissible mink encephalopathy agent from cattle, which has molecular features similar to those of the L-type BSE agent, as also shown in bovinized transgenic mice. In sharp contrast, hamsters could no...

  16. Evidence for microbial carbon and sulfur cycling in deeply buried ridge flank basalt

    Science.gov (United States)

    Lever, Mark A.; Rouxel, Olivier; Alt, Jeffrey C.; Shimizu, Nobumichi; Ono, Shuhei; Coggon, Rosalind M.; Shanks, Wayne C.; Lapham, Laura; Elvert, Marcus; Prieto-Mollar, Xavier; Hinrichs, Kai-Uwe; Inagaki, Fumio; Teske, Andreas

    2013-01-01

    Sediment-covered basalt on the flanks of mid-ocean ridges constitutes most of Earth's oceanic crust, but the composition and metabolic function of its microbial ecosystem are largely unknown. By drilling into 3.5-million-year-old subseafloor basalt, we demonstrated the presence of methane- and sulfur-cycling microbes on the eastern flank of the Juan de Fuca Ridge. Depth horizons with functional genes indicative of methane-cycling and sulfate-reducing microorganisms are enriched in solid-phase sulfur and total organic carbon, host δ13C- and δ34S-isotopic values with a biological imprint, and show clear signs of microbial activity when incubated in the laboratory. Downcore changes in carbon and sulfur cycling show discrete geochemical intervals with chemoautotrophic δ13C signatures locally attenuated by heterotrophic metabolism.

  17. 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.

  18. The hamster cheek pouch model for field cancerization studies.

    Science.gov (United States)

    Monti-Hughes, Andrea; Aromando, Romina F; Pérez, Miguel A; Schwint, Amanda E; Itoiz, Maria E

    2015-02-01

    External carcinogens, such as tobacco and alcohol, induce molecular changes in large areas of oral mucosa, which increase the risk of malignant transformation. This condition, known as 'field cancerization', can be detected in biopsy specimens using histochemical techniques, even before histological alterations are identified. The efficacy of these histochemical techniques as biomarkers of early cancerization must be demonstrated in appropriate models. The hamster cheek pouch oral cancer model, universally employed in biological studies and in studies for the prevention and treatment of oral cancer, is also an excellent model of field cancerization. The carcinogen is applied in solution to the surface of the mucosa and induces alterations that recapitulate the stages of cancerization in human oral mucosa. We have demonstrated that the following can be used for the early detection of cancerized tissue: silver staining of nucleolar organizer regions; the Feulgen reaction to stain DNA followed by ploidy analysis; immunohistochemical analysis of fibroblast growth factor-2, immunohistochemical labeling of proliferating cells to demonstrate an increase of epithelial cell proliferation in the absence of inflammation; and changes in markers of angiogenesis (i.e. those indicating vascular endothelial growth factor activity, endothelial cell proliferation and vascular density). The hamster cheek pouch model of oral cancer was also proposed and validated by our group for boron neutron capture therapy studies for the treatment of oral cancer. Clinical trials of this novel treatment modality have been performed and are underway for certain tumor types and localizations. Having demonstrated the efficacy of boron neutron capture therapy to control tumors in the hamster cheek pouch oral cancer model, we adapted the model for the long-term study of field cancerized tissue. We demonstrated the inhibitory effect of boron neutron capture therapy on tumor development in field

  19. STAT2 Knockout Syrian Hamsters Support Enhanced Replication and Pathogenicity of Human Adenovirus, Revealing an Important Role of Type I Interferon Response in Viral Control.

    Directory of Open Access Journals (Sweden)

    Karoly Toth

    2015-08-01

    Full Text Available Human adenoviruses have been studied extensively in cell culture and have been a model for studies in molecular, cellular, and medical biology. However, much less is known about adenovirus replication and pathogenesis in vivo in a permissive host because of the lack of an adequate animal model. Presently, the most frequently used permissive immunocompetent animal model for human adenovirus infection is the Syrian hamster. Species C human adenoviruses replicate in these animals and cause pathology that is similar to that seen with humans. Here, we report findings with a new Syrian hamster strain in which the STAT2 gene was functionally knocked out by site-specific gene targeting. Adenovirus-infected STAT2 knockout hamsters demonstrated an accentuated pathology compared to the wild-type control animals, and the virus load in the organs of STAT2 knockout animals was 100- to 1000-fold higher than that in wild-type hamsters. Notably, the adaptive immune response to adenovirus is not adversely affected in STAT2 knockout hamsters, and surviving hamsters cleared the infection by 7 to 10 days post challenge. We show that the Type I interferon pathway is disrupted in these hamsters, revealing the critical role of interferon-stimulated genes in controlling adenovirus infection. This is the first study to report findings with a genetically modified Syrian hamster infected with a virus. Further, this is the first study to show that the Type I interferon pathway plays a role in inhibiting human adenovirus replication in a permissive animal model. Besides providing an insight into adenovirus infection in humans, our results are also interesting from the perspective of the animal model: STAT2 knockout Syrian hamster may also be an important animal model for studying other viral infections, including Ebola-, hanta-, and dengue viruses, where Type I interferon-mediated innate immunity prevents wild type hamsters from being effectively infected to be used as

  20. STAT2 Knockout Syrian Hamsters Support Enhanced Replication and Pathogenicity of Human Adenovirus, Revealing an Important Role of Type I Interferon Response in Viral Control.

    Science.gov (United States)

    Toth, Karoly; Lee, Sang R; Ying, Baoling; Spencer, Jacqueline F; Tollefson, Ann E; Sagartz, John E; Kong, Il-Keun; Wang, Zhongde; Wold, William S M

    2015-08-01

    Human adenoviruses have been studied extensively in cell culture and have been a model for studies in molecular, cellular, and medical biology. However, much less is known about adenovirus replication and pathogenesis in vivo in a permissive host because of the lack of an adequate animal model. Presently, the most frequently used permissive immunocompetent animal model for human adenovirus infection is the Syrian hamster. Species C human adenoviruses replicate in these animals and cause pathology that is similar to that seen with humans. Here, we report findings with a new Syrian hamster strain in which the STAT2 gene was functionally knocked out by site-specific gene targeting. Adenovirus-infected STAT2 knockout hamsters demonstrated an accentuated pathology compared to the wild-type control animals, and the virus load in the organs of STAT2 knockout animals was 100- to 1000-fold higher than that in wild-type hamsters. Notably, the adaptive immune response to adenovirus is not adversely affected in STAT2 knockout hamsters, and surviving hamsters cleared the infection by 7 to 10 days post challenge. We show that the Type I interferon pathway is disrupted in these hamsters, revealing the critical role of interferon-stimulated genes in controlling adenovirus infection. This is the first study to report findings with a genetically modified Syrian hamster infected with a virus. Further, this is the first study to show that the Type I interferon pathway plays a role in inhibiting human adenovirus replication in a permissive animal model. Besides providing an insight into adenovirus infection in humans, our results are also interesting from the perspective of the animal model: STAT2 knockout Syrian hamster may also be an important animal model for studying other viral infections, including Ebola-, hanta-, and dengue viruses, where Type I interferon-mediated innate immunity prevents wild type hamsters from being effectively infected to be used as animal models.

  1. Congenital Transmission of Experimental Leishmaniasis in a Hamster Model

    Science.gov (United States)

    Osorio, Yaneth; Rodriguez, Luz D.; Bonilla, Diana L.; Peniche, Alex G.; Henao, Hector; Saldarriaga, Omar; Travi, Bruno L.

    2012-01-01

    Little information is available on transplacental transmission of Leishmania spp. We determined the frequency and impact of congenital infection caused by Leishmania panamensis or L. donovani in experimentally infected hamsters. A polymerase chain reaction showed that congenital transmission occurred in 25.8% (24 of 93) of offspring born to L. panamensis-infected hamsters and 14.6% (11 of 75) offspring born to L. donovani-infected hamsters. Mortality during lactation was higher in offspring born to L. panamensis-infected hamsters and offspring born to L. donovani-infected hamsters than controls, and lymphoproliferation to Leishmania was more frequent in offspring born to L. panamensis-infected hamsters (17.4%, 11 of 63) than in offspring born to L. donovani-infected hamsters (8.5%, 3 of 35). After weaning, only offspring born to L. donovani-infected hamsters had lower weight gain (P < 0.001) and hematocrit levels (P = 0.0045) than controls. Challenge of offspring born to L. panamensis-infected hamsters with L. panamensis showed no differences in lesion evolution, and offspring born to L. donovani-infected hamsters were more susceptible to L. donovani challenge than controls. Consequently, prenatal exposure of hamsters to L. donovani significantly increased the mortality risk and susceptibility to secondary homologous infection. PMID:22556079

  2. Scarless and sequential gene modification in Pseudomonas using PCR product flanked by short homology regions

    Directory of Open Access Journals (Sweden)

    Liang Rubing

    2010-08-01

    Full Text Available Abstract Background The lambda Red recombination system has been used to inactivate chromosomal genes in various bacteria and fungi. The procedure consists of electroporating a polymerase chain reaction (PCR fragment containing antibiotic cassette flanked by homology regions to the target locus into a strain that can express the lambda Red proteins (Gam, Bet, Exo. Results Here a scarless gene modification strategy based on the Red recombination system has been developed to modify Pseudomonas genome DNA via sequential deletion of multiple targets. This process was mediated by plasmid pRKaraRed encoding the Red proteins regulated by PBAD promoter, which was functional in P. aeruginosa as well as in other bacteria. First the target gene was substituted for the sacB-bla cassette flanked by short homology regions (50 bp, and then this marker gene cassette could be replaced by the PCR fragment flanking itself, generating target-deleted genome without any remnants and no change happened to the surrounding region. Twenty genes involved in the synthesis and regulation pathways of the phenazine derivate, pyocyanin, were modified, including one single-point mutation and deletion of two large operons. The recombination efficiencies ranged from 88% to 98%. Multiple-gene modification was also achieved, generating a triple-gene deletion strain PCA (PAO1, ΔphzHΔphzMΔphzS, which could produce another phenazine derivate, phenazine-1-carboxylic acid (PCA, efficiently and exclusively. Conclusions This lambda Red-based technique can be used to generate scarless and sequential gene modification mutants of P. aeruginosa efficiently, using one-step PCR product flanked by short homology regions. Single-point mutation, scarless deletion of genes can be achieved easily in less than three days. This method may give a new way to construct genetically modified P. aeruginosa strains more efficiently and advance the regulatory network study of this organism.

  3. Ahne hamster lõikuskuul/ Tambet Kaugema

    Index Scriptorium Estoniae

    Kaugema, Tambet

    2010-01-01

    Eesti Nuku- ja Noorsoteatri jõululavastusest "Ahne hamster ja värvilised jäälilled", autor Miloš Macourek, tõlkija Leo Metsar, lavastaja ja muusikaline kujundaja Virko Annus, mängib Tarmo Männard. Esietendus 21. novembril Köismäe tornis

  4. Disparities in activity levels and learning ability between Djungarian hamster (Phodopus sungorus) and Roborovskii hamster (Phodopus roborovskii).

    Science.gov (United States)

    Ikeda, Hiromi; Nagasawa, Mao; Yamaguchi, Takeshi; Minaminaka, Kimie; Goda, Ryosei; Chowdhury, Vishwajit S; Yasuo, Shinobu; Furuse, Mitsuhiro

    2017-03-01

    The Djungarian hamster and the Roborovskii hamster belong to the same genus of Phodopus. However, the Djungarian hamster is tame and shows sedative behavior, while Roborovskii hamster is not tame and shows high levels of locomotor activity. Hyperactivity occurs in animals with tameless behavior. Tameness or tamelessness behavior is very important because tameness helps for breeding and controlling as well as it enables a strong human-animal bond. In the present study, we examined the relationships between activity levels and cognitive function in Djungarian and Roborovskii hamsters. Three types of behavioral tests were performed to analyze their activity levels, memory and leaning ability. The levels of L- and D-amino acids and monoamines in the brain were then determined. Roborovskii hamsters showed significantly higher locomotor activity than Djungarian hamsters. Memory ability was not significantly different between the two hamsters, but Roborovskii hamsters showed lower learning ability. Brain levels of D-serine which is related to enhancement in memory and learning ability, were significantly higher in Djungarian hamsters, but the reverse was true for brain dopamine and serotonin levels. These results suggest that these differences in brain metabolism may be related to the behavioral differences between the two hamsters. © 2016 Japanese Society of Animal Science.

  5. Flanking Variation Influences Rates of Stutter in Simple Repeats

    Directory of Open Access Journals (Sweden)

    August E. Woerner

    2017-11-01

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

  6. Flanking region sequence information to refine microRNA target ...

    Indian Academy of Sciences (India)

    Our methodology attained a higher average accuracy of 0.88, average sensitivity and specificity of 0.81 and 0.94, respectively, and areas under the curves (AUCs) for all the four models scored above 0.9, suggesting better performance by our methodology and a possible role of flanking regions in microRNA targeting ...

  7. Rainfall Variability along the Southern Flank of the Bambouto ...

    African Journals Online (AJOL)

    This paper presents the rainfall variability along the southern flank of the Bambouto mountain. Data were collected from rain gauges, while spatial variability was estimated through daily recorded data. Monthly and annual data were used to draw isohyetes via the triangular method, with linear interpolations between ...

  8. Single nucleotide polymorphisms in the 5'-flanking region of the ...

    African Journals Online (AJOL)

    Prolactin (PRL), a polypeptide hormone synthesized and secreted by the animal's anterior pituitary gland, plays an important role in the regulation of mammalian lactation and avian reproduction. Considering the significant association between single nucleotide polymorphisms (SNPs) in the 5'-flanking region of PRL and ...

  9. Provenance of sandstone on the western flank of Anambra Basin ...

    African Journals Online (AJOL)

    The localities are in the western flank of the Anambra basin, southwestern Nigeria. Petrographic study shows that the sandstone deposits are composed of variable amounts of quartz, feldspars and lithic fragments with minor occurrence of authigenic silica and chlorite cements. Quartz is the predominant detrital mineral in all ...

  10. Rainfall Variability along the Southern Flank of the Bambouto ...

    African Journals Online (AJOL)

    2008-10-27

    Oct 27, 2008 ... This paper presents the rainfall variability along the southern flank of the Bambouto mountain. Data were collected from rain gauges, while spatial variability was estimated through daily recorded data. ... mensuelles et annuelles basé sur la méthode des triangles, avec interpolation linéaire pour tous les.

  11. Flanking region sequence information to refine microRNA target ...

    Indian Academy of Sciences (India)

    Prakash

    block of four bases or more could be required by the target sites to find suitable interactions with the targeting ... end, and (ii) randomized target UTRs retaining the same nucleotide composition, in order to avoid any ... analysis were the complete target region of 70-base flanking sequences around the microRNA target site.

  12. Red-Flanked Duiker Cephalophus rufilatus found in Bugungu Game ...

    African Journals Online (AJOL)

    Red-Flanked Duiker Cephalophus rufilatus found in Bugungu Game Reserve, Uganda. C Allan. Abstract. Journal of East African Natural History Vol. 85 (1&2) 1996: 87-90. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  13. Unilateral flank ovariohysterectomy in guinea pigs (Cavia porcellus).

    Science.gov (United States)

    Rozanska, D; Rozanski, P; Orzelski, M; Chlebicka, N; Putowska, K

    2016-11-01

    To describe a simple, minimally invasive method of ovariohysterectomy via a unilateral flank approach in guinea pigs, for use in routine desexing of healthy female guinea pigs or treatment of ovarian cysts. The subjects of this retrospective study were 41 client-owned guinea pigs submitted for routine desexing or treatment of ovarian cysts. They included 16 healthy female guinea pigs aged 8-12 months (Group 1), and 15 females aged from 9 months to 3 years (Group 2), and 10 females aged from 3 to 7 years (Group 3) with different-sized ovarian cysts. Prior to surgery, the animals received clinical examination, blood testing (complete blood count and serum biochemistry profile) and examination of the abdomen using ultrasonography, to assess the condition of the reproductive tract and ensure the guinea pigs were fit for surgery. Ovariohysterectomy was performed via a unilateral flank incision made close to the erector spinae muscle starting approximately 1 cm caudal to the last rib. Both ovaries, uterine horns, and the uterine cervix were localised, ligated, and dissected through this unilateral retroperitoneal incision. Ovariohysterectomy was successfully completed via a single flank incision in 38/41 (93%) guinea pigs. Three guinea pigs with ovarian cysts from Group 3, which were >6 years old died during surgery due to circulatory and respiratory failure under anaesthesia. In the remaining 38 cases, surgery proceeded without complications. A further two guinea pigs from Group 3 were reluctant to move or eat for the first 3 days after surgery but recovered after provision of supportive care. All 38 animals fully recovered and wound healing was normal. This is the first report of ovariohysterectomy via a unilateral flank incision in guinea pigs. This approach is a simple, minimally invasive and safe alternative to the midline or bilateral flank approaches currently used for surgery of the reproductive tract in guinea pigs.

  14. Histiocytic Sarcoma and Bilateral Facial Vein Thrombosis in a Siberian Hamster (Phodopus sungorus).

    Science.gov (United States)

    Coble, Dondrae J; Shoemaker, Margaret; Harrington, Bonnie; Dardenne, Adrienne D; Bolon, Brad

    2015-04-01

    A 21-mo-old, male Siberian hamster (Phodopus sungorus) presented with left-sided facial swelling, proptosis of the left eye, and blepharospasm of the right eye. The hamster had been used only for breeding. Because of the poor prognosis, the hamster was euthanized without additional diagnostic assays or treatments. Routine gross pathologic evaluation demonstrated exophthalmos and presumptive hyphema of the left eye, bilateral facial edema, freely movable nodules within the mesentery, white foci within the liver, and a large mass effacing the cranial pole of the right kidney. On histologic evaluation, the mesenteric nodules and liver foci expressed histiocytic marker CD163 and thus were diagnosed as sites of histiocytic sarcoma, whereas the kidney mass was a well-differentiated renal cell carcinoma. The facial swelling resulted from bilateral, chronic, severe, branching thrombi in many facial veins. Additional age-related histopathologic findings were observed in other organs, including diffuse glomerulopathy, nesidioblastosis (pancreatic islet neoformation), and multiple foci of severe cartilage degeneration in the axial skeleton. To our knowledge, this report provides the first description of histiocytic sarcoma in a Siberian hamster.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Congenital Transmission of Experimental Leishmaniasis in a Hamster Model

    OpenAIRE

    Osorio, Yaneth; Rodriguez, Luz D.; Diana L Bonilla; Peniche, Alex G.; Henao, Hector; Saldarriaga, Omar; Bruno L. Travi

    2012-01-01

    Little information is available on transplacental transmission of Leishmania spp. We determined the frequency and impact of congenital infection caused by Leishmania panamensis or L. donovani in experimentally infected hamsters. A polymerase chain reaction showed that congenital transmission occurred in 25.8% (24 of 93) of offspring born to L. panamensis-infected hamsters and 14.6% (11 of 75) offspring born to L. donovani-infected hamsters. Mortality during lactation was higher in offspring b...

  17. Passive immunization prevents induction of Lyme arthritis in LSH hamsters.

    OpenAIRE

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

    1990-01-01

    We determined that sera obtained from hamsters infected with Borrelia burgdorferi could prevent the induction of Lyme arthritis. When irradiated hamsters were administered immune serum and subsequently challenged with B. burgdorferi, no evidence of infection was detected. Recipients failed to develop swelling of the hind paws, and no histopathologic changes were detected. In addition, B. burgdorferi was not recovered from tissues of hamsters that were passively immunized. By contrast, irradia...

  18. 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.

  19. ABSCESSO TESTICULAR EM HAMSTER: RELATO DE CASO

    OpenAIRE

    R.M. Santos; G. D. A. Araguchi; G. R. S. Sluizas; M. C. Menezes; Lega, E.; B. Paludeto; V. Fardin

    2012-01-01

    The Hamster, rodent originating from the Middle East, is a species studied along with other laboratory animals as experimental models in scientific papers and currently is also created as a pet, by virtue of being docile, easy to handle and require little space for survival. The suppurative processes in domestic animals are relatively frequent. Due to infectious diseases or purulent course of aggressiveness of the environment in which they live. The habit of storing food in the cheeks with sh...

  20. Effect of mebendazole on fibrosarcoma in hamsters

    African Journals Online (AJOL)

    Original Research Article. Effect of mebendazole on fibrosarcoma in hamsters. Dušica J Popović1*, Dušan Lalošević1, Kosta J Popović2, Ivan Čapo1, Jovan K. Popović3 and Dejan Miljković1. 1Department of Histology and Embryology, 2Department of Pharmacy, 3Department of Pharmacology, Toxicology and Clinical.

  1. Dietary lipid saturation influences environmental temperature preference but not resting metabolic rate in the Djungarian Hamster (Phodopus sungorus).

    Science.gov (United States)

    Pannorfi, Ryan; Zee, Barry M; Vatnick, Itzick; Berner, Nancy; Hiebert, Sara M

    2012-01-01

    Heterothermic rodents increase self-selection of diets rich in polyunsaturated fatty acids (PUFAs) when exposed to cold, short days, or short-day melatonin profiles, and Djungarian hamsters (Phodopus sungorus) do so in long days in response to cold exposure alone. To determine whether Djungarian hamsters are also capable of selecting a thermal environment in response to dietary lipid composition, continuously normothermic hamsters were fed either a PUFA-rich diet or a diet rich in saturated fatty acids (SFAs) for 6-10 wk and given a choice of thermal environments. As predicted, SFA-fed hamsters were more likely than PUFA-fed hamsters to occupy the single heated corner of their cage ([Formula: see text]) and were most likely to show this diet-related difference in behavior when T(a) fell within the thermal neutral zone. Respirometry revealed no effect of diet on whole-animal or mass-specific resting metabolic rate or on lower critical temperature. The results are more consistent with the homeoviscous adaptation hypothesis, which predicts that organisms should make physiological and/or behavioral adjustments that preserve membrane fluidity within a relatively small range, than with the membrane pacemaker hypothesis, which predicts that high PUFA content in membrane phospholipids should increase basal metabolic rate.

  2. Tissue distribution of indium after repeated intratracheal instillations of indium-tin oxide into the lungs of hamsters.

    Science.gov (United States)

    Tanaka, Akiyo; Hirata, Miyuki; Matsumura, Nagisa; Kiyohara, Yutaka

    2015-01-01

    The aim of this study was to analyze the tissue distribution of indium after intratracheally instilling indium-tin oxide (ITO) into the lungs of hamsters. Male Syrian hamsters received an intratracheal dose of 3 mg/kg or 6 mg/kg of ITO particles containing 2.2 mg/kg or 4.5 mg/kg of indium, twice weekly for 8 weeks. In parallel, control hamsters received only an intratracheal dose of distilled water. A subset of hamsters was euthanized periodically throughout the study from 8 up to 78 weeks after the final instillation. The distribution of indium in the lungs, liver, kidneys and spleen, as well as pathological changes in the liver, kidneys, and spleen, was determined. The contents of indium in the lungs in the two ITO groups gradually decreased over the 78-week observation period, with elimination half-lives of approximately 142 weeks for the 3 mg/kg ITO group and 124 weeks for the 6 mg/kg ITO. The indium concentrations in the liver, kidneys, and spleen gradually increased throughout the observation period. Although foci of the lesions were observed histopathologically in the extrapulmonary organs among the two ITO groups, the control group showed similar lesions. The results clearly demonstrate that the clearance of indium from the body is extremely slow after intratracheal instillation in hamsters.

  3. Molecular and immunological characterization of the first allergenic lipocalin in hamster: the major allergen from Siberian hamster (Phodopus sungorus).

    Science.gov (United States)

    Torres, José Alberto; de Las Heras, Manuel; Maroto, Aroa Sanz; Vivanco, Fernando; Sastre, Joaquín; Pastor-Vargas, Carlos

    2014-08-22

    The most frequent pet allergy is to cat and dog, but in recent years, it has become increasingly popular to have other pets, and the risk of exposure to new allergens is more prevalent. The list of new pets includes hamsters, and one of the most popular hamsters is the Siberian hamster (Phodopus sungorus). The aim of this study was the characterization and cloning of the major allergen from this hamster. The study of its allergenicity and cross-reactivity could improve the specific diagnosis and treatment for hamster-allergic patients. Thirteen Siberian hamster-allergic patients were recruited at the outpatient clinic. Protein extracts were prepared from the hair, urine, and salivary glands of four hamster species (European, golden, Siberian, and Roborovski). IgE-binding proteins were detected by immunoblotting and identified by mass spectrometry. The recombinant protein was produced in Escherichia coli and then purified by metal chelate affinity chromatography. The allergenic properties of the recombinant protein were tested by ELISA and immunoblotting, and biological activity was tested according to capacity for basophil activation. Three IgE-binding proteins were identified in extracts obtained from Siberian hamster hair, urine, and salivary glands. All proteins corresponded to the same protein, which was identified as a lipocalin. This lipocalin had no cross-reactivity with common and golden hamsters. The recombinant allergen was cloned and purified, showing similar IgE reactivity in vitro to Siberian hamster protein extracts. Also, the recombinant allergen was capable of producing biological activation in vivo. The major Siberian hamster allergen was cloned, and allergenic properties were characterized, providing a new tool for specific diagnosis of allergy to Siberian hamster. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Diet-induced metabolic hamster model of nonalcoholic fatty liver disease

    OpenAIRE

    Prakash, Satya; Bhathena, Jasmine; Urbanska,Aleksandra; Kulamarva,Arun; Malhotra, Meenakshi; Martoni, Christopher; Paul, Arghya

    2011-01-01

    Jasmine Bhathena, Arun Kulamarva, Christopher Martoni, Aleksandra Malgorzata Urbanska, Meenakshi Malhotra, Arghya Paul, Satya PrakashBiomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Artificial Cells and Organs Research Centre, Faculty of Medicine, McGill University, Montreal, Québec, CanadaBackground: Obesity, hypercholesterolemia, elevated triglycerides, and type 2 diabetes are major risk factors for metabolic syndrome. Hamsters, un...

  5. Use of the Syrian golden hamster for the induction of intraoral abscesses by sutures contaminated with human subgingival plaque.

    Science.gov (United States)

    Wasfy, M O; McMahon, K T; Santos, A C; Minah, G E; Falkler, W A; Lloyd, D R

    1994-02-01

    Analysis of normal oral flora in 150 cheek pouches of hamsters (Mesocricetus auratus) defined the microbial working environment and demonstrated the absence of human oral black-pigmented bacteria. Silk sutures saturated with Porphyromonas gingivalis, Prevotella intermedia or subgingival plaque were used to close wounds made in hamster's cheek pouches. Abscesses were formed when sutures had solitary P. gingivalis or other bacteria mixed with P. gingivalis or when P. intermedia was mixed with other bacteria besides P. gingivalis. A concentration of black-pigmented bacteria emanating from 3 x 10(5) colony-forming units/inoculum was required for abscess formation. Six abscesses (14.3%) were developed in association with the presence of other odontopathic bacteria, primarily Fusobacterium nucleatum and Actinomyces viscosus. The hamster cheek pouch with iatrogenic wounds closed with plaque-impregnated sutures is a novel and effective model to study the pathology of wound infections and virulence of human subgingival organisms.

  6. Asymmetric learning to avoid heterospecific males in Mesocricetus hamsters.

    Science.gov (United States)

    delBarco-Trillo, Javier; Johnston, Robert E

    2012-08-01

    If a female mates with a male of a closely related species, her fitness is likely to decline. Consequently, females may develop behavioral mechanisms to avoid mating with heterospecific males. In some species, one such mechanism is for adult females to learn to discriminate against heterospecific males after exposure to such males. We have previously shown that adult, female Syrian hamsters (Mesocricetus auratus) learn to discriminate against male Turkish hamsters (Mesocricetus brandti) after exposure to a single heterospecific male during 8 days across a wire-mesh barrier. Here we repeated that experiment but this time we exposed female Turkish hamsters to a male Syrian hamster for 8 days and then measured sexual and aggressive behaviors towards that heterospecific male and towards a conspecific male. In contrast to female Syrian hamsters, female Turkish hamsters did not differ in their latency to go into lordosis or in any measure of aggression towards either type of male. Female Turkish hamsters spent less time in lordosis with the heterospecific male, but the percentage of trials in which females copulated with conspecific and heterospecific males did not differ. When comparing females from both species that had been exposed to a heterospecific male for 8days, female Syrian hamsters copulated less and were more aggressive towards the heterospecific male compared to the behavior of female Turkish hamsters. We discuss how this asymmetric response between females of the two species may be due to the much larger geographical range of Turkish hamsters compared to Syrian hamsters. Copyright © 2012 Elsevier GmbH. All rights reserved.

  7. File list: InP.Emb.05.AllAg.Embryonic_flank [Chip-atlas[Archive

    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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  10. File list: ALL.Emb.05.AllAg.Embryonic_flank [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  11. File list: ALL.Emb.10.AllAg.Embryonic_flank [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  12. File list: InP.Emb.50.AllAg.Embryonic_flank [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  13. File list: InP.Emb.20.AllAg.Embryonic_flank [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  14. Ice burn: protecting the flank during renal cryotherapy.

    Science.gov (United States)

    Young, Jennifer L; Sountoulides, Petros; Kolla, Surendra B; Pick, Donald L; Kaufmann, Oskar B; Huynh, Victor B; Kaplan, Adam G; Ortiz, Cervando; Louie, Michael K; Andrade, Lorena A; Osann, Kathryn E; McDougall, Elspeth M; Clayman, Ralph V

    2010-08-01

    Cryoablation is a viable minimally invasive strategy for the treatment of small renal masses. One of the most common postoperative complaints is pain or paresthesia at the cryoprobe insertion site. The use of a 14-gauge angiocatheter to insulate the flank during renal cryotherapy was investigated. Six Yorkshire swine underwent laparoscopy-guided percutaneous cryoablation of the upper and lower poles of both kidneys with a 1.47 mm (17 gauge) cryoneedle. Treatment consisted of a double 10-minute freeze separated by a 5-minute active thaw. Trials were randomized to placement of the cryoneedle directly through the flank or through a 14-gauge angiocatheter as an insulating sheath. Temperatures were recorded adjacent to the cryoneedle at two depths in the flank with a Multi-Point Thermal Sensor. Twelve trials were completed each with a bare and sheathed cryoneedle. The coldest temperature observed was -26 degrees C for the bare cryoneedle and -21 degrees C for the sheathed cryoneedle. At the outer sensor, there was a 4.1 degrees C increase in mean temperature for freeze 1, and 6.2 degrees C increase in mean temperature for freeze 2 with sheath use. At the inner sensor, there was a 3.0 degrees C increase in mean temperature for freeze 1, and 9.4 degrees C increase in mean temperature for freeze 2 with sheath use. There was a trend toward statistical significance of sheath insulation at the outer (p = 0.07) and inner (p = 0.08) temperature sensors. A 14-gauge angiocatheter may provide some insulation and thereby might help protect against "ice burn" during renal cryotherapy.

  15. Thermostability of sperm nuclei assessed by microinjection into hamster oocytes

    Science.gov (United States)

    Nuclei isolated from spermatozoa of various species (golden hamster, mouse, human, rooster, and the fish tilapia) were heated at 60 degrees-125 degrees C for 20-120 min and then microinjected into hamster oocytes to determine whether they could decondense and develop into pronucl...

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

    African Journals Online (AJOL)

    Polyclonal antibodies are mixtures of monoclonal antibodies that were produced against different epitops. The goal of this project is to know the production, purification and horseradish peroxidase (HRP) conjugation of polyclonal antibodies against hamster immunoglobulins in rabbits. 300 ìg/300 ìl of ten hamster ...

  17. Characteristics of 263K Scrapie Agent in Multiple Hamster Species

    Science.gov (United States)

    Barbian, Kent D.; Race, Brent; Favara, Cynthia; Gardner, Don; Taubner, Lara; Porcella, Stephen; Race, Richard

    2009-01-01

    Transmissible spongiform encephalopathy (TSE) diseases are known to cross species barriers, but the pathologic and biochemical changes that occur during transmission are not well understood. To better understand these changes, we infected 6 hamster species with 263K hamster scrapie strain and, after each of 3 successive passages in the new species, analyzed abnormal proteinase K (PK)–resistant prion protein (PrPres) glycoform ratios, PrPres PK sensitivity, incubation periods, and lesion profiles. Unique 263K molecular and biochemical profiles evolved in each of the infected hamster species. Characteristics of 263K in the new hamster species seemed to correlate best with host factors rather than agent strain. Furthermore, 2 polymorphic regions of the prion protein amino acid sequence correlated with profile differences in these TSE-infected hamster species. PMID:19193264

  18. Precision-cut hamster liver slices as an ex vivo model to study amoebic liver abscess.

    Science.gov (United States)

    Carranza-Rosales, Pilar; Santiago-Mauricio, María Guadalupe; Guzmán-Delgado, Nancy Elena; Vargas-Villarreal, Javier; Lozano-Garza, Gerardo; Ventura-Juárez, Javier; Balderas-Rentería, Isaías; Morán-Martínez, Javier; Gandolfi, A Jay

    2010-10-01

    Entamoeba histolytica is the etiological agent of amoebiasis, the second cause of global morbidity and mortality due to parasitic diseases in humans. In approximately 1% of the cases, amoebas penetrate the intestinal mucosa and spread to other organs, producing extra-intestinal lesions, among which amoebic liver abscess (ALA) is the most common. To study ALA, in vivo and in vitro models are used. However, animal models may pose ethical issues, and are time-consuming and costly; and cell cultures represent isolated cellular lineages. The present study reports the infection of precision-cut hamster liver slices with Entamoeba histolytica trophozoites. The infection time-course, including tissue damage, parallels findings previously reported in the animal model. At the same time amoebic virulence factors were detected in the infected slices. This new model to study ALA is simple and reproducible, and employs less than 1/3 of the hamsters required for in vivo analyses. Copyright 2010 Elsevier Inc. All rights reserved.

  19. Revealing the kinetics of Leishmania chagasi infection in the male genital system of hamsters.

    Science.gov (United States)

    Quintal, Amanda P N; Borges, Bruna C; Brígido, Paula C; Silva, Rebecca T; Notário, Ana F; Santos, Marlus A; de Souza, Maria A; Nascimento, Fernanda G O; Mundim, Antônio V; Costa, Guilherme M J; Vasconcelos, André B; da Silva, Claudio V

    2016-03-29

    Leishmaniasis causes alterations and lesions in the genital system, which leads to azoospermia and testicular atrophy in animals during the chronic phase of the infection. The aim of this study was to reveal the kinetics of Leishmania chagasi infection in the genital system of male golden hamsters (Mesocricetus auratus). Animals were intraperitoneally inoculated with amastigotes from L. chagasi. At different time points animals were euthanized and genital organs processed for histo-pathological, qPCR, cytokines and testosterone detection assays. Our results showed a high parasite load in testis, followed by an increase of pro-inflammatory cytokines IL1-β, TNF-α and IFN-γ, and testosterone. Subsequently, IL-4 expression was upregulated and basal parasite persistence in testis was observed using the experimental approach. Extracellular amastigotes migrated to the epididymis posing as a potential major factor of parasite persistence and venereal transmission of L. chagasi infection in hamsters.

  20. Southward flow on the western flank of the Florida Current

    Science.gov (United States)

    Soloviev, Alexander V.; Hirons, Amy; Maingot, Christopher; Dean, Cayla W.; Dodge, Richard E.; Yankovsky, Alexander E.; Wood, Jon; Weisberg, Robert H.; Luther, Mark E.; McCreary, Julian P.

    2017-07-01

    A suite of long-term in situ measurements in the Straits of Florida, including the ADCP bottom moorings at an 11-m isobath and 244-m isobath (Miami Terrace) and several ADCP ship transects, have revealed a remarkable feature of the ocean circulation - southward flow on the western, coastal flank of the Florida Current. We have observed three forms of the southward flow - a seasonally varying coastal countercurrent, an undercurrent jet attached to the Florida shelf, and an intermittent undercurrent on the Miami Terrace. According to a 13-year monthly climatology obtained from the near-shore mooring, the coastal countercurrent is a persistent feature from October through January. The southward flow in the form of an undercurrent jet attached to the continental slope was observed during five ship transects from April through September but was not observed during three transects in February, March, and November. This undercurrent jet is well mixed due to strong shear at its top associated with the northward direction of the surface flow (Florida Current) and friction at the bottom. At the same time, no statistically significant seasonal cycle has been observed in the undercurrent flow on the Miami Terrace. Theoretical considerations suggest that several processes could drive the southward current, including interaction between the Florida Current and the shelf, as well as forcing that is independent of the Florida Current. The exact nature of the southward flow on the western flank of the Florida Current is, however, unknown.

  1. Plasma Transport at the Magnetospheric Flank Boundary. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Otto, Antonius

    2012-04-23

    Progress is highlighted in these areas: 1. Model of magnetic reconnection induced by three-dimensional Kelvin Helmholtz (KH) modes at the magnetospheric flank boundary; 2. Quantitative evaluation of mass transport from the magnetosheath onto closed geomagnetic field for northward IMF; 3. Comparison of mass transfer by cusp reconnection and Flank Kelvin Helmholtz modes; 4. Entropy constraint and plasma transport in the magnetotail - a new mechanism for current sheet thinning; 5. Test particle model for mass transport onto closed geomagnetic field for northward IMF; 6. Influence of density asymmetry and magnetic shear on (a) the linear and nonlinear growth of 3D Kelvin Helmholtz (KH) modes, and (b) three-dimensional KH mediated mass transport; 7. Examination of entropy and plasma transport in the magnetotail; 8. Entropy change and plasma transport by KH mediated reconnection - mixing and heating of plasma; 9. Entropy and plasma transport in the magnetotail - tail reconnection; and, 10. Wave coupling at the magnetospheric boundary and generation of kinetic Alfven waves.

  2. Reverse time migration of prism waves for salt flank delineation

    KAUST Repository

    Dai, Wei

    2013-09-22

    In this paper, we present a new reverse time migration method for imaging salt flanks with prism wave reflections. It consists of four steps: (1) migrating the seismic data with conventional RTM to give the RTM image; (2) using the RTM image as a reflectivity model to simulate source-side reflections with the Born approximation; (3) zero-lag correlation of the source-side reflection wavefields and receiver-side wavefields to produce the prism wave migration image; and (4) repeating steps 2 and 3 for the receiver-side reflections. An advantage of this method is that there is no need to pick the horizontal reflectors prior to migration of the prism waves. It also separately images the vertical structures at a different step to reduce crosstalk interference. The disadvantage of prism wave migration algorithm is that its computational cost is twice that of conventional RTM. The empirical results with a salt model suggest that prism wave migration can be an effective method for salt flank delineation in the absence of diving waves.

  3. Passaging impact of H9N2 avian influenza virus in hamsters on its pathogenicity and genetic variability.

    Science.gov (United States)

    Shaib, Houssam A; Cochet, Nelly; Ribeiro, Thierry; Abdel Nour, Afif M; Nemer, Georges; Azhar, Esam; Iyer, Archana; Kumosani, Taha; Harakeh, Steve; Barbour, Elie K

    2014-05-14

    Avian influenza viruses of the H9N2 subtype have been reported to cause human infections. This study demonstrates the impact of nasal viral passaging of avian H9N2 in hamsters on its cross species-pathogenic adaptability and variability of amino acid sequences of the hemagglutinin (HA) and neuraminidase (NA) stalk. Three intranasal passagings of avian H9N2 in hamsters P1, P2, and P3 were accomplished. Morbidity signs and lesions were observed three days post viral inoculation. The HA test was used for presumptive detection of H9N2 virus in the trachea and lungs of the hamsters challenged with the differently passaged viruses. Different primers were used for PCR amplification of the HA1 and NA stalk regions of the differently passaged H9N2 viruses, followed by sequence alignment. The morbidity signs indicated low pathogenicity of the differently passaged H9N2 viruses in hamsters. The frequency of gross and microscopic lesions in the tracheas and lungs were insignificantly different among hamsters challenged with the differently passaged H9N2 viruses (p > 0.05). There was 100% similarity in the amino acid sequence of the HA gene of most passaged viruses. The amino acid sequence of the neuraminidase in the third passaged H9N2 virus recovered from lungs showed a R46P mutation that might have a role in the pathogenic adaptability of P3 viruses in hamsters' lungs. The apparent adaptation of avian H9N2 virus to mammalian cells is in agreement with the World Health Organization's alertness for a possible public health threat by this adaptable virus.

  4. Determining injuries from posterior and flank stab wounds using computed tomography tractography.

    Science.gov (United States)

    Bansal, Vishal; Reid, Chris M; Fortlage, Dale; Lee, Jeanne; Kobayashi, Leslie; Doucet, Jay; Coimbra, Raul

    2014-04-01

    Unlike anterior stab wounds (SW), in which local exploration may direct management, posterior SW can be challenging to evaluate. Traditional triple contrast computed tomography (CT) imaging is cumbersome and technician-dependent. The present study examines the role of CT tractography as a strategy to manage select patients with back and flank SW. Hemodynamically stable patients with back and flank SW were studied. After resuscitation, Betadine- or Visipaque®-soaked sterile sponges were inserted into each SW for the estimated depth of the wound. Patients underwent abdominal helical CT scanning, including intravenous contrast, as the sole abdominal imaging study. Images were reviewed by an attending radiologist and trauma surgeon. The tractogram was evaluated to determine SW trajectory and injury to intra- or retroperitoneal organs, vascular structures, the diaphragm, and the urinary tract. Complete patient demographics including operative management and injuries were collected. Forty-one patients underwent CT tractography. In 11 patients, tractography detected violation of the intra- or retroperitoneal cavity leading to operative exploration. Injuries detected included: the spleen (two), colon (one), colonic mesentery (one), kidney (kidney), diaphragm (kidney), pneumothorax (seven), hemothorax (two), iliac artery (one), and traumatic abdominal wall hernia (two). In all patients, none had negative CT findings that failed observation. In this series, CT tractography is a safe and effective imaging strategy to evaluate posterior torso SW. It is unknown whether CT tractography is superior to traditional imaging modalities. Other uses for CT tractography may include determining trajectory from missile wounds and tangential penetrating injuries.

  5. Diet-induced metabolic hamster model of nonalcoholic fatty liver disease

    Directory of Open Access Journals (Sweden)

    Bhathena J

    2011-06-01

    Full Text Available Jasmine Bhathena, Arun Kulamarva, Christopher Martoni, Aleksandra Malgorzata Urbanska, Meenakshi Malhotra, Arghya Paul, Satya PrakashBiomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Artificial Cells and Organs Research Centre, Faculty of Medicine, McGill University, Montreal, Québec, CanadaBackground: Obesity, hypercholesterolemia, elevated triglycerides, and type 2 diabetes are major risk factors for metabolic syndrome. Hamsters, unlike rats or mice, respond well to diet-induced obesity, increase body mass and adiposity on group housing, and increase food intake due to social confrontation-induced stress. They have a cardiovascular and hepatic system similar to that of humans, and can thus be a useful model for human pathophysiology.Methods: Experiments were planned to develop a diet-induced Bio F1B Golden Syrian hamster model of dyslipidemia and associated nonalcoholic fatty liver disease in the metabolic syndrome. Hamsters were fed a normal control diet, a high-fat/high-cholesterol diet, a high-fat/high-cholesterol/methionine-deficient/choline-devoid diet, and a high-fat/high-cholesterol/choline-deficient diet. Serum total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, glucose, atherogenic index, and body weight were quantified biweekly. Fat deposition in the liver was observed and assessed following lipid staining with hematoxylin and eosin and with oil red O.Results: In this study, we established a diet-induced Bio F1B Golden Syrian hamster model for studying dyslipidemia and associated nonalcoholic fatty liver disease in the metabolic syndrome. Hyperlipidemia and elevated serum glucose concentrations were induced using this diet. Atherogenic index was elevated, increasing the risk for a cardiovascular event. Histological analysis of liver specimens at the end of four weeks showed increased fat deposition in the liver of animals fed

  6. Development and validation of an Onchocerca ochengi microfilarial hamster model for onchocerciasis drug screens.

    Science.gov (United States)

    Mbah, Glory Enjong; Ayiseh, Rene Bilingwe; Cho-Ngwa, Fidelis

    2016-08-11

    Onchocerciasis, caused by the parasitic nematode, Onchocerca volvulus afflicts some 37 million people worldwide, and is the second leading infectious cause of blindness globally. The only currently recommended drug for treatment of the disease, ivermectin, is only microfilaricidal and has serious adverse effects in individuals co-infected with high loads of Loa loa microfilariae (mf), prompting the search for new and better drugs. Onchocerciasis drug discovery studies have so far been based on in vivo models using Onchocerca species which are not the closest to O. volvulus, and which may therefore, not adequately mimic the natural infection in humans. Therefore, this study was carried out to develop a better drug screening model for onchocerciasis, based on the use of cow-derived O. ochengi, the closest known relative of O. volvulus. Mf of O. ochengi were injected subcutaneously at the nape of Syrian hamsters (Mesocricetus auratus) and BALB/c mice. The skin, and especially the earlobes of the animals were examined for mf 15-31 days after infection. For selected model validation, the hamsters were treated with ivermectin at 150 or 600 μg/kg body weight and examined 30 days after infection for mf. For L. loa studies in hamsters, isolated mf were injected intraperitoneally and animal organs were examined on day 26 for mf. The Syrian hamsters were found to be the more permissive to O. ochengi mf as fully viable mf were recovered from them on day 30, compared to BALB/c mice where such mf were recovered on day 15, but not 30. However, both animals were not permissive to L. loa mf even by day 15. Interestingly, more than 50 % of the total O. ochengi mf recovered were from the earlobes. The number of mf injected was directly proportional to the number recovered. Ivermectin at both concentrations tested completely eliminated the O. ochengi mf from the hamsters. This study reveals the Syrian hamster as an appropriate small animal model for screening of novel compounds

  7. Investigation of possible oncogenic action of zinc polycarboxylate cement by implantation in mice and hamsters.

    Science.gov (United States)

    Main, J H; Mock, D; Beagrie, G S; Smith, D C

    1975-01-01

    Powdered, sterilized zinc polycarboxylate was implanted subcutaneously in 56 young hamsters and 54 mice, using equal numbers of each sex, with 24 sham operated hamsters and 26 mice as controls. The hamsters were sacrificed after 15 months and the mice after 12. Implant material was recovered from one of 42 surviving mice and from 16 of 43 surviving hamsters. Benign adenomas of the gut, thyroid, sebaceous glands and ovary were found in 3 experimental mice and in one control. Benign adrenal adenomas were found in 3 experimental hamsters and in one control. One control hamster developed a rhabdomyosarcoma in a limb. One experimental hamster developed a leiomysarcoma in close relation to an implant.

  8. Cyclooxygenase-2 Expression in Hamster and Human Pancreatic Neoplasia1

    Science.gov (United States)

    Yip-Schneider, Michele T; Savage, Jesse J; Hertzler, Dean A; Cummings, William O

    2006-01-01

    Abstract Cyclooxygenase-2 (COX-2) has been implicated in the development of gastrointestinal malignancies. The aim of the present study was to determine COX-2 expression/activity throughout stages of experimental and human pancreatic neoplasia. COX-2 immunohistochemistry was performed in pancreata of hamsters subjected to the carcinogen N-nitrosobis-(2-oxopropyl)amine (BOP) and in human pancreatic tumors. COX-2 activity was determined by prostaglandin E2 assay in tumor versus matched normal pancreatic tissues. The activity of the COX inhibitor sulindac was tested in the PC-1 hamster pancreatic cancer model. COX-2 expression was elevated in all pancreatic intraepithelial neoplasias (PanINs) and adenocarcinomas. In BOP-treated hamsters, there were significant progressive elevations in COX-2 expression throughout pancreatic tumorigenesis. In human samples, peak COX-2 expression occurred in PanIN2 lesions and remained moderately elevated in PanIN3 and adenocarcinoma tissues. COX-2 activity was significantly elevated in hamster and human pancreatic cancers compared to pair-matched normal pancreas. Furthermore, hamster pancreatic tumor engraftment/formation in the PC-1 hamster pancreatic cancer model was reduced 4.9-fold by oral administration of sulindac. Increased COX-2 expression is an early event in pancreatic carcinogeneses. The BOP-induced hamster carcinogenesis model is a representative model used to study the role of COX-2 in well-differentiated pancreatic tumorigenesis. COX inhibitors may have a role in preventing tumor engraftment/formation. PMID:16820089

  9. Evidence of Multiple Flank Collapse at Volcan Baru, Panama

    Science.gov (United States)

    Herrick, J. A.; Rose, W. I.

    2009-12-01

    Michigan Tech's Peace Corps Master's International program (PCMI) in Geological Hazards has enabled several long-term investigations of active volcanoes in Latin America. To contribute to volcanic hazard assessments in Panama and achieve the goals defined by the PCMI program, we developed this debris avalanche project to address outstanding questions regarding Volcan Baru's most devastating event - massive slope failure of the western flank. Relying on basic mapping tools as well as the 2007 USGS Open-File Report focusing on hazard assessments of Panama's youngest and potentially active volcano, identification of the debris avalanche deposits (DAD) required detailed field investigations to determine the limits of the units. Extending across an area larger than 600 km2, field strategies were developed based on outcrop exposures within drainages and road-cuts. Aerial photos and DEMs of Baru's nested craters were interpreted by earlier scientists as the remains of two collapsed flanks. The results from in-depth field traverses provide several important discoveries: paleosols and sharp contacts within the stratigraphy indicate multiple DAD, deeply weathered hummocks red-flag the deposits more than 50-km away from Baru's crater, and high-quality radiocarbon samples (up to 45-cm long fragments of entrained wood) lie in the distal reaches of the debris flow area. During the 2008-2009 field seasons, we received assistance from the University of Panama, Civil Protection, and Panama's National Institute of Geography. Support from local experts and feedback from professional scientists of the Smithsonian Institution and Costa Rica's Institute of Electricity were invaluable. The 2-year investment in volcanic hazard studies has brought together resources from several countries as well as fresh data that will benefit the residents and emergency management officials of Panama. Jigsaw fractured clasts lie within Volcan Baru's debris avalanche deposits more than 28 km south of the

  10. Cluster observations of surface waves on the dawn flank magnetopause

    Directory of Open Access Journals (Sweden)

    C. J. Owen

    2004-03-01

    Full Text Available On 14 June 2001 the four Cluster spacecraft recorded multiple encounters of the dawn-side flank magnetopause. The characteristics of the observed electron populations varied between a cold, dense magnetosheath population and warmer, more rarified boundary layer population on a quasi-periodic basis. The demarcation between these two populations can be readily identified by gradients in the scalar temperature of the electrons. An analysis of the differences in the observed timings of the boundary at each spacecraft indicates that these magnetopause crossings are consistent with a surface wave moving across the flank magnetopause. When compared to the orientation of the magnetopause expected from models, we find that the leading edges of these waves are approximately 45° steeper than the trailing edges, consistent with the Kelvin-Helmholtz (KH driving mechanism. A stability analysis of this interval suggests that the magnetopause is marginally stable to this mechanism during this event. Periods in which the analysis predicts that the magnetopause is unstable correspond to observations of greater wave steepening. Analysis of the pulses suggests that the waves have an average wavelength of approximately 3.4 RE and move at an average speed of ~65km s-1 in an anti-sunward and northward direction, despite the spacecraft location somewhat south of the GSE Z=0 plane. This wave propagation direction lies close to perpendicular to the average magnetic field direction in the external magnetosheath, suggesting that these waves may preferentially propagate in the direction that requires no bending of these external field lines

    Key words. Magnetospheric physics (magnetospheric configuration and dynamics; MHD waves and unstabilities; solar wind-magnetosphere interactions

  11. Cytotoxic effects of sulfuric acid mist, carbon particulates, and their mixtures on hamster tracheal epithelium

    Energy Technology Data Exchange (ETDEWEB)

    Schiff, L.J. (IIT Research Inst., Chicago, IL); Bryne, M.M.; Fenters, J.D.; Graham, J.A.; Gardner, D.E.

    1979-08-01

    Hamster tracheal tissue was used to study the effects of H/sub 2/SO/sub 4/ mist, carbon particles, and mixtures of the two on cilia beating frequency and morphological alterations of respiratory epithelium. Hamsters were exposed for 3 h to 1.1 mg/m/sup 3/ H/sub 2/SO/sub 4/ (mean size, 0.12 ..mu..m) and 1.5 mg/m/sup 3/ carbon (mean size, 0.3 ..mu..m) particle aerosols alone or in combination. Trachea of animals exposed in vivo to the mixture and held in vivo showed cytotoxic effects in the epithelium that were greater than those produced by either the acid mist or carbon alone. In tracheas of hamsters exposed in vivo and maintained in vitro the damage produced by acid mist-carbon mixture did not differ significantly from that produced by acid mist per se but was greater than that observed after exposure to carbon. Organ cultures of tracheal rings exposed for 3 h to a 1:10/sup 6/ dilution of concentrated H/sub 2/SO/sub 4/ and 100 ..mu..g/ml carbon produced epithelial damage in vitro similar to that seen in in vivo exposures. The extent of recovery over a period of 72 h was also studied following different combinations of in vivo and in vitro exposure and/or maintenance.

  12. DNA double-strand break repair is impaired in presenescent Syrian hamster fibroblasts.

    Science.gov (United States)

    Solovjeva, Ljudmila; Firsanov, Denis; Vasilishina, Anastasia; Chagin, Vadim; Pleskach, Nadezhda; Kropotov, Andrey; Svetlova, Maria

    2015-10-12

    Studies of DNA damage response are critical for the comprehensive understanding of age-related changes in cells, tissues and organisms. Syrian hamster cells halt proliferation and become presenescent after several passages in standard conditions of cultivation due to what is known as "culture stress". Using proliferating young and non-dividing presenescent cells in primary cultures of Syrian hamster fibroblasts, we defined their response to the action of radiomimetic drug bleomycin (BL) that induces DNA double-strand breaks (DSBs). The effect of the drug was estimated by immunoblotting and immunofluorescence microscopy using the antibody to phosphorylated histone H2AX (gH2AX), which is generally accepted as a DSB marker. At all stages of the cell cycle, both presenescent and young cells demonstrated variability of the number of gH2AX foci per nucleus. gH2AX focus induction was found to be independent from BL-hydrolase expression. Some differences in DSB repair process between BL-treated young and presenescent Syrian hamster cells were observed: (1) the kinetics of gH2AX focus loss in G0 fibroblasts of young culture was faster than in cells that prematurely stopped dividing; (2) presenescent cells were characterized by a slower recruitment of DSB repair proteins 53BP1, phospho-DNA-PK and phospho-ATM to gH2AX focal sites, while the rate of phosphorylated ATM/ATR substrate accumulation was the same as that in young cells. Our results demonstrate an impairment of DSB repair in prematurely aged Syrian hamster fibroblasts in comparison with young fibroblasts, suggesting age-related differences in response to BL therapy.

  13. The response of vegetation on the Andean flank in western Amazonia to Pleistocene climate change.

    Science.gov (United States)

    Cárdenas, Macarena L; Gosling, William D; Sherlock, Sarah C; Poole, Imogen; Pennington, R Toby; Mothes, Patricia

    2011-02-25

    A reconstruction of past environmental change from Ecuador reveals the response of lower montane forest on the Andean flank in western Amazonia to glacial-interglacial global climate change. Radiometric dating of volcanic ash indicates that deposition occurred ~324,000 to 193,000 years ago during parts of Marine Isotope Stages 9, 7, and 6. Fossil pollen and wood preserved within organic sediments suggest that the composition of the forest altered radically in response to glacial-interglacial climate change. The presence of Podocarpus macrofossils ~1000 meters below the lower limit of their modern distribution indicates a relative cooling of at least 5°C during glacials and persistence of wet conditions. Interglacial deposits contain thermophilic palms suggesting warm and wet climates. Hence, global temperature change can radically alter vegetation communities and biodiversity in this region.

  14. Identification of Genomic Insertion and Flanking Sequence of G2-EPSPS and GAT Transgenes in Soybean Using Whole Genome Sequencing Method

    Science.gov (United States)

    Guo, Bingfu; Guo, Yong; Hong, Huilong; Qiu, Li-Juan

    2016-01-01

    Molecular characterization of sequence flanking exogenous fragment insertion is essential for safety assessment and labeling of genetically modified organism (GMO). In this study, the T-DNA insertion sites and flanking sequences were identified in two newly developed transgenic glyphosate-tolerant soybeans GE-J16 and ZH10-6 based on whole genome sequencing (WGS) method. More than 22.4 Gb sequence data (∼21 × coverage) for each line was generated on Illumina HiSeq 2500 platform. The junction reads mapped to boundaries of T-DNA and flanking sequences in these two events were identified by comparing all sequencing reads with soybean reference genome and sequence of transgenic vector. The putative insertion loci and flanking sequences were further confirmed by PCR amplification, Sanger sequencing, and co-segregation analysis. All these analyses supported that exogenous T-DNA fragments were integrated in positions of Chr19: 50543767–50543792 and Chr17: 7980527–7980541 in these two transgenic lines. Identification of genomic insertion sites of G2-EPSPS and GAT transgenes will facilitate the utilization of their glyphosate-tolerant traits in soybean breeding program. These results also demonstrated that WGS was a cost-effective and rapid method for identifying sites of T-DNA insertions and flanking sequences in soybean. PMID:27462336

  15. Identification of genomic insertion and flanking sequence of G2-EPSPS and GAT transgenes in soybean using whole genome sequencing method

    Directory of Open Access Journals (Sweden)

    Bingfu Guo

    2016-07-01

    Full Text Available Molecular characterization of sequences flanking exogenous fragment insertions is essential for safety assessment and labeling of genetically modified organisms (GMO. In this study, the T-DNA insertion sites and flanking sequences were identified in two newly developed transgenic glyphosate-tolerant soybeans GE-J16 and ZH10-6 based on whole genome sequencing (WGS method. About 21 Gb sequence data (~21× coverage for each line was generated on Illumina HiSeq 2500 platform. The junction reads mapped to boundary of T-DNA and flanking sequences in these two events were identified by comparing all sequencing reads with soybean reference genome and sequence of transgenic vector. The putative insertion loci and flanking sequences were further confirmed by PCR amplification, Sanger sequencing, and co-segregation analysis. All these analyses supported that exogenous T-DNA fragments were integrated in positions of Chr19: 50543767-50543792 and Chr17: 7980527-7980541 in these two transgenic lines. Identification of the genomic insertion site of the G2-EPSPS and GAT transgenes will facilitate the use of their glyphosate-tolerant traits in soybean breeding program. These results also demonstrated that WGS is a cost-effective and rapid method of identifying sites of T-DNA insertions and flanking sequences in soybean.

  16. A role for glucose in hypothermic hamsters

    Science.gov (United States)

    Resch, G. E.; Musacchia, X. J.

    1976-01-01

    Hypothermic hamsters at a rectal temperature of 7 C showed a fivefold increase in survival times from 20 to 100.5 hr when infused with glucose which maintained a blood level at about 45 mg/100 ml. A potential role for osmotic effects of the infusion was tested and eliminated. There was no improvement in survival of 3-O-methylglucose or dextran 40-infused animals. The fact that death eventually occurs even in the glucose-infused animal after about 4 days and that oxygen consumption undergoes a slow decrement in that period suggests that hypothermic survival is not wholly substrate limited. Radioactive tracer showed that localization of the C-14 was greatest in brain tissue and diaphragm, intermediate in heart and kidney, and lowest in skeletal muscle and liver. The significance of the label at sites important to respiration and circulation was presented.

  17. Mutation induction in synchronous hamster cells

    Energy Technology Data Exchange (ETDEWEB)

    Aebersold, P.M.

    1975-11-01

    Mutagenesis of synchronous Mutahinese hamster cells by 5-bromodeoxyuridine (BUdR) shows pronounced cell cycle dependency. Resistance to 6-thioguanine (6-TG) and ouabain are induced maximally by BUdR at different times early in the DNA synthesis period, suggesting that the genes coding for hypoxanthine-guanine phosphoribosyltransferase (HGPRT) and the (Na/sup +/K/sup +/)-associated ATPase of the plasma membrane are replicated early in the DNA synthesis period. Although BUdR induces mutations in specific genes only when present during their replication, the rate of mutation induction is not linearly related to the amount of BUdR incorporated into DNA. The data show a BUdR concentration threshold for mutation induction, suggesting that BUdR exerts some deterimental allosteric effect on DNA synthesis enzymes.

  18. Fasting-induced daily torpor in desert hamsters (Phodopus roborovskii).

    Science.gov (United States)

    Chi, Qing-Sheng; Wan, Xin-Rong; Geiser, Fritz; Wang, De-Hua

    2016-09-01

    Daily torpor is frequently expressed in small rodents when facing energetically unfavorable ambient conditions. Desert hamsters (Phodopus roborovskii, ~20g) appear to be an exception as they have been described as homeothermic. However, we hypothesized that they can use torpor because we observed reversible decreases of body temperature (Tb) in fasted hamsters. To test this hypothesis we (i) randomly exposed fasted summer-acclimated hamsters to ambient temperatures (Tas) ranging from 5 to 30°C or (ii) supplied them with different rations of food at Ta 23°C. All desert hamsters showed heterothermy with the lowest mean Tb of 31.4±1.9°C (minimum, 29.0°C) and 31.8±2.0°C (minimum, 29.0°C) when fasted at Ta of 23°C and 19°C, respectively. Below Ta 19°C, the lowest Tb and metabolic rate increased and the proportion of hamsters using heterothermy declined. At Ta 5°C, nearly all hamsters remained normothermic by increasing heat production, suggesting that the heterothermy only occurs in moderately cold conditions, perhaps to avoid freezing at extremely low Tas. During heterothermy, Tbs below 31°C with metabolic rates below 25% of those during normothermia were detected in four individuals at Ta of 19°C and 23°C. Consequently, by definition, our observations confirm that fasted desert hamsters are capable of shallow daily torpor. The negative correlation between the lowest Tbs and amount of food supply shows that heterothermy was mainly triggered by food shortage. Our data indicate that summer-acclimated desert hamsters can express fasting-induced shallow daily torpor, which may be of significance for energy conservation and survival in the wild. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Evidence for a metabolic limitation of survival in hypothermic hamsters.

    Science.gov (United States)

    Prewitt, R. L.; Anderson, G. L.; Musacchia, X. J.

    1972-01-01

    The underlying factors limiting survival in the hypothermic state are studied. Hamsters of both sexes, clipped and unclipped, were inducted into profound hypothermia by the helium cold method until they reached a temperature between 7 and 10 C. It appears that the primary cause of death is failure of respiration due to the depletion of carbohydrate energy supplies and may explain why survival time in hypothermia is shorter than the normal hibernation time of the hamster.

  20. Patterns of nucleotides that flank substitutions in human orthologous genes

    Directory of Open Access Journals (Sweden)

    Huang Zhuoran

    2010-07-01

    Full Text Available Abstract Background Sequence context is an important aspect of base mutagenesis, and three-base periodicity is an intrinsic property of coding sequences. However, how three-base periodicity is influenced in the vicinity of substitutions is still unclear. The effect of context on mutagenesis should be revealed in the usage of nucleotides that flank substitutions. Relative entropy (also known as Kullback-Leibler divergence is useful for finding unusual patterns in biological sequences. Results Using relative entropy, we visualized the periodic patterns in the context of substitutions in human orthologous genes. Neighbouring patterns differed both among substitution categories and within a category that occurred at three codon positions. Transition tended to occur in periodic sequences relative to transversion. Periodic signals were stronger in a set of flanking sequences of substitutions that occurred at the third-codon positions than in those that occurred at the first- or second-codon positions. To determine how the three-base periodicity was affected near the substitution sites, we fitted a sine model to the values of the relative entropy. A sine of period equal to 3 is a good approximation for the three-base periodicity at sites not in close vicinity to some substitutions. These periods were interrupted near the substitution site and then reappeared away from substitutions. A comparative analysis between the native and codon-shuffled datasets suggested that the codon usage frequency was not the sole origin of the three-base periodicity, implying that the native order of codons also played an important role in this periodicity. Synonymous codon shuffling revealed that synonymous codon usage bias was one of the factors responsible for the observed three-base periodicity. Conclusions Our results offer an efficient way to illustrate unusual periodic patterns in the context of substitutions and provide further insight into the origin of three

  1. Ocular pathological changes in hamsters experimentally infected with Schistosoma mansoni.

    Science.gov (United States)

    Ismail, H I H; Ashour, D S; Abou Rayia, D M; Ali, A L

    2016-11-01

    Ocular lesions have been reported in patients with schistosomiasis; however, the problem with studying schistosomal infection of the human eye is that biopsies are almost impossible to take, and histopathological examination of suspicious lesions can only be undertaken post-mortem or after enucleation. This work aimed to study the possible effects and pathogenesis of schistosomiasis on the eye. This study involved 55 hamsters; five hamsters remained non-infected and the remaining 50 hamsters were infected with Schistosoma mansoni cercariae. Infected hamsters were sacrificed on weeks 8, 12, 16 and 20 post-infection (pi). Eye sections were prepared and stained for histopathological and immunohistochemical studies. Histopathological changes detected in hamsters infected after 16 and 20 weeks included looseness and oedema of the innermost retinal layers together with hyperplastic polypoid growth. Neither eggs nor granulomata were detected in eye sections throughout the experimental period. Deposition of S. mansoni antigen was revealed in 35% of infected hamsters. Later, on weeks 16 and 20 pi, moderate subepithelial conjuctival deposits and marked subchoroidal and scleral deposition were detected. In conclusion, the deposition of schistosomal antigen and immune complexes may play a pivotal role in the ocular changes that occur in schistosomiasis, even in the absence of detectable Schistosoma eggs. Schistosomiasis should be suspected in cases with unexplained ophthalmological findings, especially in endemic areas.

  2. Regulation of tonic gonadotropin release in prepubertal female hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Smith, S.G.; Matt, K.S.; Prestowitz, W.F.; Stetson, M.H.

    1982-04-01

    Basal serum gonadotropin levels were monitored weekly in female hamsters from birth to 10 weeks of age. Hamsters raised on three different photoperiods presented uniform pre- and postpubertal patterns of serum LH and FSH, suggesting that gonadotropin release in the young hamster occurs independently of ambient photoperiod. In all groups, serum LH levels increased gradually in animals up to 4 weeks of age, after which levels plateaued at 50--100 ng/ml. Serum FSH was markedly elevated in 2- and 3-week-old hamsters (800--1200 ng/ml), but remained at 200--400 ng/ml in all other groups. We next examined the change in the responsiveness of the pituitary to exogenous gonadotropin-releasing hormone (GnRH) challenge. Female hamsters 2 days of age failed to respond to any dose (0.025--1000 ng) of GnRH, while 10-day old females responded in typical dose-dependent fashion. GnRH-stimulated LH release first occurred in 6-day-old hamsters and was maximal by day 9, whereas FSH release first occurred on day 8 and was maximal by day 9. The prepubertal pattern of gonadotropin release can, in part, be explained on the basis of the development of pituitary GnRH sensitivity, which occurs independently of photoperiod.

  3. Transposed genes in Arabidopsis are often associated with flanking repeats.

    Directory of Open Access Journals (Sweden)

    Margaret R Woodhouse

    2010-05-01

    Full Text Available Much of the eukaryotic genome is known to be mobile, largely due to the movement of transposons and other parasitic elements. Recent work in plants and Drosophila suggests that mobility is also a feature of many nontransposon genes and gene families. Indeed, analysis of the Arabidopsis genome suggested that as many as half of all genes had moved to unlinked positions since Arabidopsis diverged from papaya roughly 72 million years ago, and that these mobile genes tend to fall into distinct gene families. However, the mechanism by which single gene transposition occurred was not deduced. By comparing two closely related species, Arabidopsis thaliana and Arabidopsis lyrata, we sought to determine the nature of gene transposition in Arabidopsis. We found that certain categories of genes are much more likely to have transposed than others, and that many of these transposed genes are flanked by direct repeat sequence that was homologous to sequence within the orthologous target site in A. lyrata and which was predominantly genic in identity. We suggest that intrachromosomal recombination between tandemly duplicated sequences, and subsequent insertion of the circular product, is the predominant mechanism of gene transposition.

  4. The study of double flank micro gear roll testing

    Science.gov (United States)

    Liu, Yen-Chih; An, Nai-Chun; Yang, Shu-Han; Yan, Sheng-Zhan; Chen, Shih-Lu

    2011-12-01

    The recent fast development of multifunctional portable electronic devices results in the obvious requirement of micro mechanical components. Due to the popular application of the micro actuators and the micro gearboxes, micro gears become the frequently used micro mechanical component in a small device such as small intelligent robots or dental surgical devices. Metal Industries Research & Development Centre (MIRDC) has successfully developed a small speed reducer that comprises several micro planetary gear trains. The module of this micro planetary gear train is 0.12mm. Since all gears are small, no commercial instrument is available for inspection. How to evaluate the manufacturing quality of micro gears becomes an important issue. This study focuses on the double flank gear rolling test and a specialized apparatus is built referring to the testing requirements in the international standards. The center distance variation during the rolling test is recorded and two indices, the total radial composite deviation and the maximum tooth-to-tooth radial composite deviation, are calculated to evaluate the accuracy grade of the micro gears. Experimental results show that the accuracy of the micro gear made by the cold forging process conforms to grade 7 defined in the ISO 1328-2 while grade 2 is achieved if the JGMA 116-02 is specified.

  5. Flank pseudohernia following posterior rib fracture: a case report.

    Science.gov (United States)

    Butensky, Adam M; Gruss, Leah P; Gleit, Zachary L

    2016-10-01

    A pseudohernia is an abdominal wall bulge that may be mistaken for a hernia but that lacks the disruption of the abdominal wall that characterizes a hernia. Thus, the natural history and treatment of this condition differ from those of a hernia. This is the first report of a pseudohernia due to cough-associated rib fracture. A case of pseudohernia due to fractures of the 10(th) and 11(th) ribs in a 68-year-old white woman is presented. The patient suffered from a major coughing episode 1 year prior to her presentation, after which she noted a progressively enlarging bulge in her left flank. Computed tomography demonstrated a bulge in the abdominal wall containing bowel and spleen but with all muscle and fascial layers intact; in addition, lateral 10(th) rib and posterior 11(th) rib fractures were noted. As there was no defect in muscle or fascia, we diagnosed a pseudohernia, likely due to a denervation injury from the fractured ribs. Symptomatic treatment was recommended, including wearing a corset and referral to a pain management clinic. Symptomatic treatment is thought to be the mainstay of therapy for pseudohernias, as surgical intervention is unlikely to be of benefit.

  6. Sodium Ion Dynamics in the Magnetospheric Flanks of Mercury

    Science.gov (United States)

    Aizawa, Sae; Delcourt, Dominique; Terada, Naoki

    2018-01-01

    We investigate the transport of planetary ions in the magnetospheric flanks of Mercury. In situ measurements from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft show evidences of Kelvin-Helmholtz instability development in this region of space, due to the velocity shear between the downtail streaming flow of solar wind originating protons in the magnetosheath and the magnetospheric populations. Ions that originate from the planet exosphere and that gain access to this region of space may be transported across the magnetopause along meandering orbits. We examine this transport using single-particle trajectory calculations in model Magnetohydrodynamics simulations of the Kelvin-Helmholtz instability. We show that heavy ions of planetary origin such as Na+ may experience prominent nonadiabatic energization as they E × B drift across large-scale rolled up vortices. This energization is controlled by the characteristics of the electric field burst encountered along the particle path, the net energy change realized corresponding to the maximum E × B drift energy. This nonadiabatic energization also is responsible for prominent scattering of the particles toward the direction perpendicular to the magnetic field.

  7. Predator odour and its impact on male fertility and reproduction in Phodopus campbelli hamsters

    Science.gov (United States)

    Vasilieva, N. Y.; Cherepanova, E. V.; von Holst, D.; Apfelbach, R.

    This study investigated the influence of cat urine odour in suppressing development and fertility in Campbell's hamster males. Exposure to this odour from postnatal day 11 until day 45 (sexual maturation) resulted in reduced sex organ weights, reduced testosterone levels and in an increase in abnormalities of the synaptonemal complex in both sex chromosomes and autosomes. Subsequent breeding experiments revealed a significant decrease in litter size. All these data indicate a severe effect of predator odour on the breeding success of potential prey species. It is assumed that these effects are caused by the sulphurous compounds in the urine; however, the underlying mechanisms are not yet known.

  8. Pulmonary toxicity in hamsters of smoke particles from Kuwaiti oil fires.

    Science.gov (United States)

    Brain, J D; Long, N C; Wolfthal, S F; Dumyahn, T; Dockery, D W

    1998-03-01

    The Kuwaiti oil wells set on fire by retreating Iraqi troops at the end of the Persian Gulf War released complex particles, inorganic and organic gases, and hydrocarbons into the atmosphere, damaging the environment where many people live and work. In this study, we assessed the health effects of particles from the Kuwaiti oil fires by instilling hamsters intratracheally with particles (long-term effects of exposure to these particles remains unknown, further studies are needed to fully assess the health effects of the Kuwaiti oil fires.

  9. Male-specific submaxillary gland protein, a lipocalin allergen of the golden hamster, differs from the lipocalin allergens of Siberian and Roborovski dwarf hamsters.

    Science.gov (United States)

    Hilger, Christiane; Dubey, Ved P; Lentz, Delphine; Davril, Caroline; Revets, Dominique; Muller, Claude P; Diederich, Claire; De La Barrière, Hélène; Codreanu-Morel, Françoise; Morisset, Martine; Lehners, Christiane; De, Prabir K; Hentges, François

    2015-01-01

    An increasing number of asthma cases upon exposure to hamsters and anaphylactic reactions following hamster bites are being reported, but the allergens responsible are still poorly characterized. In the Golden hamster, male-specific submaxillary gland protein (MSP), a lipocalin expressed in a sex- and tissue-specific manner in the submaxillary and lacrimal glands, is secreted in the saliva, tears and urine. The purpose of this study was to determine if MSP is an allergen, to identify IgE-reactive proteins of different hamster species and to analyse potential cross-reactivities. Fur extracts were prepared from four hamster species. Hamster-allergic patients were selected based on a history of positive IgE-test to hamster epithelium. The IgE-reactivity of patients' sera was investigated by means of immunoblot and ELISA. IgE-reactive proteins in fur extracts and the submaxillary gland were identified using anti-MSP antibodies, Edman sequencing or mass spectrometry. MSP was purified from Golden hamster and recombinant MSP was expressed in E. coli. Four patients had IgE-antibodies against 20.5-kDa and 24-kDa proteins of Golden hamster fur extract, which were identified as MSP. IgE-reactive MSP-like proteins were detected in European hamster fur extract. Three patient sera showed IgE-reactive bands at 17-21 kDa in Siberian and Roborovski hamster fur extracts. These proteins were identified as two closely related lipocalins. Immunoblot inhibition experiments showed that they are cross-reactive and are different from MSP. MSP lipocalin of the Golden hamster was identified as an allergen, and it is different from the cross-reactive lipocalin allergens of Siberian and Roborovski hamsters. Our findings highlight the need for specific tools for the in vitro and in vivo diagnosis of allergy to different hamster species. © 2015 S. Karger AG, Basel.

  10. Crustal structure on the northeastern flank of the Kenya rift

    Science.gov (United States)

    Prodehl, C.; Jacob, A. W. B.; Thybo, H.; Dindi, E.; Stangl, R.

    1994-09-01

    The KRISP flank line E converges with the Kenya rift at an angle of about 45° and is approximately parallel to the older Anza graben to the north. The depth to the basement is almost zero along the entire onshore part of the profile with higher velocities at the southeastern end indicative of extensive Precambrian gabbroic intrusions in the upper crust. The Moho shallows steadily from about 35 km at the southeastern end of the profile to about 24 km under Lake Turkana. Even though the Moho rises fairly steadily, there is significant heterogeneity in the crust above it. This shows that the extension is unevenly distributed between the upper and the lower crust. The Moho is laminated and variably reflective. Compared to the KRISP cross-line D further south, the crust is unexpectedly thin and shows extension increasing in a northerly direction. This extension is probably not associated with the Anza and Kenya rifting but with the profile's position on the slope of the Kenya dome. The indications are that there is a relatively abrupt change to a 20-km Moho depth near the Lake Turkana Central shotpoint. This change to a mid-rift crustal thickness occurs not at the postulated margin at the southeastern shore of Lake Turkana but at least 50 km further to the northwest. We suggest that the position of this margin may need to be redefined. The P n velocity is quite high at 8.1 km/s. This may indicate either a cold upper mantle or anisotropy. An upper-mantle reflector has been identified between 15 and 20 km below the Moho. It dips gently away from the rift.

  11. Copulatory and agonistic behavior in Syrian hamsters following social defeat.

    Science.gov (United States)

    Jeffress, Elizabeth C; Huhman, Kim L

    2013-01-01

    Syrian hamsters are highly aggressive animals that reliably defend their home territory. After social defeat, however, hamsters no longer defend their home cage but instead display submissive and defensive behavior toward an intruder, a response that we have termed conditioned defeat. Plasma testosterone is significantly reduced in Syrian hamsters following repeated defeat suggesting that social defeat might also impair copulatory behavior. The present study aimed to determine whether copulatory behavior in male Syrian hamsters is suppressed following repeated social defeats and additionally whether exposure to a hormone-primed stimulus female after social defeat reduces the behavioral response to defeat. Hamsters were paired with an aggressive opponent for one or nine defeats using a resident-intruder model, while controls were placed into the empty cage of a resident aggressor. On the day after the last treatment, half of the hamsters were paired with a receptive female for 10 min. There were no significant differences in the copulatory behavior of defeated versus non-defeated hamsters, and the opportunity to copulate had no effect on subsequent conditioned defeat testing, as defeated animals displayed significantly more submissive behavior than did non-defeated animals. The current data suggest that conditioned defeat is not necessarily a maladaptive response to social stress, at least in terms of reproductive behavior, but may instead represent a viable behavioral strategy adopted by losing animals following social defeat. Further, these data indicate that conditioned defeat is relatively persistent and stable, as the opportunity to copulate does not reduce the subsequent display of submissive behavior. © 2013 Wiley Periodicals, Inc.

  12. Dietary fiber improves lipid homeostasis and modulates adipocytokines in hamsters.

    Science.gov (United States)

    Hung, Shao-Ching; Bartley, Glenn; Young, Scott Andrew; Albers, David Robert; Dielman, Demetrius Richard; Anderson, William Henry Kerr; Yokoyama, Wallace

    2009-09-01

    The hypocholesterolemic and hypoglycemic effects of various natural and semisynthetic dietary fibers have been studied for their potential use in the prevention and improvement of metabolic syndrome. Of these dietary fibers, hydroxypropyl methylcellulose (HPMC) has been shown to lower plasma cholesterol and reduce weight gain. However, the underlying mechanisms are not known. In the present study, we examined associations between plasma adipocytokine levels and both lipid metabolism and insulin sensitivity after HPMC intake in golden Syrian hamsters. In addition, endogenous adiponectin from hamster plasma was purified and characterized. Hamsters were treated with HPMC (2% and 4% in a high-fat diet) or 2% or 4% microcrystalline cellulose (MCC; control diet) for 8 weeks. Plasma glucose, insulin, lipids, adiponectin, leptin, and hepatic lipid levels were assessed using standard techniques. After 8 weeks of feeding, plasma total cholesterol and triglyceride levels in hamsters fed the 4% HPMC-supplemented diet were significantly lower than in hamsters fed the control diet. Moreover, a significant increase in adiponectin levels and a decrease in leptin levels were observed in hamsters fed the 4% HPMC-supplemented diet. Hamster adiponectin was found to be comprised of 244 amino acid residues with an apparent molecular weight of 30 kDa, consistent with the adiponectin reported in other species. Reductions in plasma cholesterol and triglyceride levels were correlated with a decrease in plasma leptin and an increase in adiponectin. These results suggest that adipocytokines are regulated by HPMC and may play a pivotal role in the hypocholesterolemic effect. © 2009 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Blackwell Publishing Asia Pty Ltd.

  13. Efficient Gene Targeting in Golden Syrian Hamsters by the CRISPR/Cas9 System

    OpenAIRE

    Zhiqiang Fan; Wei Li; Sang R Lee; Qinggang Meng; Bi Shi; Bunch, Thomas D.; Kenneth L White; Il-Keun Kong; Zhongde Wang

    2014-01-01

    The golden Syrian hamster is the model of choice or the only rodent model for studying many human diseases. However, the lack of gene targeting tools in hamsters severely limits their use in biomedical research. Here, we report the first successful application of the CRISPR/Cas9 system to efficiently conduct gene targeting in hamsters. We designed five synthetic single-guide RNAs (sgRNAs)--three for targeting the coding sequences for different functional domains of the hamster STAT2 protein, ...

  14. Role of caloric homeostasis and reward in alcohol intake in Syrian golden hamsters

    OpenAIRE

    Gulick, Danielle; Green, Alan I.

    2010-01-01

    The Syrian golden hamster drinks alcohol readily, but only achieves moderate blood alcohol levels, and does not go through withdrawal from alcohol. Because the hamster is a model of caloric homeostasis, both caloric content and reward value may contribute to the hamster’s alcohol consumption. The current study examines alcohol consumption in the hamster when a caloric or non-caloric sweet solution is concurrently available and caloric intake in the hamster before, during, and after exposure t...

  15. The Syrian hamster model of hantavirus pulmonary syndrome

    Science.gov (United States)

    Safronetz, David; Ebihara, Hideki; Feldmann, Heinz; Hooper, Jay W.

    2012-01-01

    Hantavirus pulmonary syndrome (HPS) is a relatively rare, but frequently fatal disease associated with New World hantaviruses, most commonly Sin Nombre and Andes viruses in North and South America, respectively. It is characterized by fever and the sudden, rapid onset of severe respiratory distress and cardiogenic shock, which can be fatal in up to 50% of cases. Currently there are no approved antiviral therapies or vaccines for the treatment or prevention of HPS. A major obstacle in the development of effective medical countermeasures against highly pathogenic agents like the hantaviruses is recapitulating the human disease as closely as possible in an appropriate and reliable animal model. To date, the only animal model that resembles HPS in humans is the Syrian hamster model. Following infection with Andes virus, hamsters develop HPS-like disease which faithfully mimics the human condition with respect to incubation period and pathophysiology of disease. Perhaps most importantly, the sudden and rapid onset of severe respiratory distress observed in humans also occurs in hamsters. The last several years has seen an increase in studies utilizing the Andes virus hamster model which have provided unique insight into HPS pathogenesis as well as potential therapeutic and vaccine strategies to treat and prevent HPS. The purpose of this article is to review the current understanding of HPS disease progression in Syrian hamsters and discuss the suitability of utilizing this model to evaluate potential medical countermeasures against HPS. PMID:22705798

  16. Regulation of lipid metabolism by obeticholic acid in hyperlipidemic hamsters.

    Science.gov (United States)

    Dong, Bin; Young, Mark; Liu, Xueqing; Singh, Amar Bahadur; Liu, Jingwen

    2017-02-01

    The farnesoid X receptor (FXR) plays critical roles in plasma cholesterol metabolism, in particular HDL-cholesterol (HDL-C) homeostasis. Obeticholic acid (OCA) is a FXR agonist being developed for treating various chronic liver diseases. Previous studies reported inconsistent effects of OCA on regulating plasma cholesterol levels in different animal models and in different patient populations. The mechanisms underlying its divergent effects have not yet been thoroughly investigated. The scavenger receptor class B type I (SR-BI) is a FXR-modulated gene and the major receptor for HDL-C. We investigated the effects of OCA on hepatic SR-BI expression and correlated such effects with plasma HDL-C levels and hepatic cholesterol efflux in hyperlipidemic hamsters. We demonstrated that OCA induced a time-dependent reduction in serum HDL-C levels after 14 days of treatment, which was accompanied by a significant reduction of liver cholesterol content and increases in fecal cholesterol in OCA-treated hamsters. Importantly, hepatic SR-BI mRNA and protein levels in hamsters were increased to 1.9- and 1.8-fold of control by OCA treatment. Further investigations in normolipidemic hamsters did not reveal OCA-induced changes in serum HDL-C levels or hepatic SR-BI expression. We conclude that OCA reduces plasma HDL-C levels and promotes transhepatic cholesterol efflux in hyperlipidemic hamsters via a mechanism involving upregulation of hepatic SR-BI.

  17. 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.

  18. Pineal melatonin synthesis in Syrian hamsters: A summary

    Science.gov (United States)

    Rollag, M. D.

    1982-12-01

    During the past decade there has been ample documentation of the proposition that the pineal gland mediates photoperiodic influences upon reproductive behavior of hamsters. It is commonly hypothesized that the pineal gland expresses its activity by transformation of photoperiodic information into an hormonal output, that hormone being melatonin. If this hypothesis is correct, there must be some essential diffrence in melatonin's output when hamsters are exposed to different photoperiodic environments. The experiments summarized in this communication analyze pineal melatonin contents in Syrian hamsters maintained in a variety of photoperiodic conditions during different physiological states. The results demonstrate that adult hamsters have a daily surge in pineal melatonin content throughout their lifetime when exposed to simulated annual photoperiodic cycles. There is some fluctuation in the amount of pineal melatonin produced during different physiological states and photoperiodic environments, but these fluctuations seem small when compared to those normally found for other regulatory hormones. When hamsters are exposed to different photoperiodic regimens, the daily melatonin surge maintains a relatively constant phase relationship with respect to the onset of daily activity. There is a concomitant change in its phase relationship with respect to light-dark transitions.

  19. 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

  20. 9 CFR 3.36 - Primary enclosures used to transport live guinea pigs and hamsters.

    Science.gov (United States)

    2010-01-01

    ... live guinea pigs and hamsters. 3.36 Section 3.36 Animals and Animal Products ANIMAL AND PLANT HEALTH..., Care, Treatment, and Transportation of Guinea Pigs and Hamsters Transportation Standards § 3.36 Primary enclosures used to transport live guinea pigs and hamsters. No person subject to the Animal Welfare...

  1. Designing the epitope flanking regions for optimal generation of CTL epitopes.

    Science.gov (United States)

    Steers, Nicholas J; Currier, Jeffrey R; Jobe, Ousman; Tovanabutra, Sodsai; Ratto-Kim, Silvia; Marovich, Mary A; Kim, Jerome H; Michael, Nelson L; Alving, Carl R; Rao, Mangala

    2014-06-12

    The flanking amino acids that surround epitopes are critical for effective antigen processing and maintenance of epitope integrity. In the present study, the frequency and characteristics of each amino acid that flanked the peptides generated from the proteasomal degradation of three different subtypes of HIV-1 Gag-p24 were determined. Synthetic flanking regions were designed based on the highest and the lowest frequencies of amino acid with the ideal characteristics at positions upstream and downstream of the proteasomal cleavage site. Peptides were synthesized that contained known CD8+ CTL-epitopes from HIV-1 Gag, CMV pp65, and vaccinia proteins HRP-2, and C16, flanked by amino acid sequences specifically designed to either generate or inhibit the known CD8+ CTL-epitopes. As predicted, the known CD8+ CTL-epitopes were effectively generated from the peptides with synthetic flanking regions specifically designed to promote epitope generation in a proteasome-dependent manner. The majority of the proteasome-generated epitopes were cleaved immediately after the C-terminal amino acid of the specific CTL-epitope. The synthetic peptide sequences containing known CD8+ CTL-epitopes with the flanking regions that promote epitope generation were effectively processed and presented to epitope specific CD8+ T-cells resulting in the production of IFN-γ. These results highlight the importance of flanking regions in promoting efficient antigen processing and presentation. This concept can have important implications in vaccine design and development strategies. Published by Elsevier Ltd.

  2. Effect of bismuth subsalicylate on Clostridium difficile colitis in hamsters.

    Science.gov (United States)

    Chang, T W; Dong, M Y; Gorbach, S L

    1990-01-01

    The therapeutic effect of bismuth subsalicylate (BSS, Pepto-Bismol) in Clostridium difficile colitis was studied in golden Syrian hamsters. C. difficile was fed to the hamsters by orogastric intubation 2-3 days after their arrival. Clindamycin (1.5 mg per animal) was given intraperitoneally 4 days later. Twenty-four hours after challenge with clindamycin, animals were given BSS at dosages of 5, 10, and 15 mg twice daily for 5 days by orogastric intubation. Controls included untreated animals and those given 5 mg of vancomycin once daily by intubation. Delay in the time of death was observed in all BSS-treated animals and was statistically significant on days 4-6 in those receiving 15 mg twice daily. Vancomycin produced a greater delay in death than did BSS. Our study suggests that BSS at a dosage of 15 mg twice daily has some therapeutic effect on C. difficile colitis in hamsters.

  3. A 55-Year Old Man with Acute Painful Flank Mass, a Case Report

    Directory of Open Access Journals (Sweden)

    Aida Alavi-Moghaddam

    2014-03-01

    Full Text Available Lumbar hernias (LH accounts for less than 1.5% of total hernia incidence. It can occur in two separate triangular areas of the flank. About 300 cases have been reported in the literature. Here, we report a 55-year old man with acute painful left side flank mass and final diagnosis of LH. The mass was appeared about three hours before admission and his pain was slight at first but became more severe gradually. He had stable vital sign and the only positive finding on his physical examination was the sphere shape, firm, mobile, and mild tender mass at his left flank.

  4. Low-dose norfloxacin and ciprofloxacin therapy worsen leptospirosis in hamster.

    Science.gov (United States)

    Wu, Dianjun; Zhang, Wenlong; Wang, Tingting; Lin, Tao; Jin, Xuemin; Xie, Xufeng; Guo, Jian; Cao, Yongguo; Wu, Rui

    2017-01-01

    Antibiotics play an important role in the treatment of leptospirosis. Many antibiotics at appropriate concentrations improved the survival rate and alleviated tissue injury, while, when dosing strategies fall below subtherapeutic levels, worse therapeutic effects are seen. In the present study, we investigated the efficacy of low-dose norfloxacin (10, 20 and 30 mg/kg) and ciprofloxacin (1, 2 and 5 mg/kg) against leptospirosis in a hamster model using Leptospira interrogans serovar Icterohaemorrhagiae. The histopathology and bacterial loads of target organs (liver, kidney and lung) were also studied by treatment with norfloxacin at the dose of 10 mg/kg in this model. Using RT-PCR, the expression of inflammatory factor IL-1β and TNF-α was analyzed by comparing the norfloxacin and untreated group. All untreated animals, serving as a negative control, displayed 50% survival rate, while hamsters treated with norfloxacin at the dose of 10 and 20 mg/kg and ciprofloxacin at the dose of 1 and 2 mg/kg showed a lower survival rate than the untreated group. Furthermore, norfloxacin at the dose of 10 mg/kg increased bacterial loads and aggravated tissue injury of target organs. The delayed induction of IL-1β and TNF-α was found in tissues of norfloxacin group. Our study indicates an increased risk associated with low-dose norfloxacin and ciprofloxacin in leptospirosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Foodborne transmission of nipah virus in Syrian hamsters.

    Science.gov (United States)

    de Wit, Emmie; Prescott, Joseph; Falzarano, Darryl; Bushmaker, Trenton; Scott, Dana; Feldmann, Heinz; Munster, Vincent J

    2014-03-01

    Since 2001, outbreaks of Nipah virus have occurred almost every year in Bangladesh with high case-fatality rates. Epidemiological data suggest that in Bangladesh, Nipah virus is transmitted from the natural reservoir, fruit bats, to humans via consumption of date palm sap contaminated by bats, with subsequent human-to-human transmission. To experimentally investigate this epidemiological association between drinking of date palm sap and human cases of Nipah virus infection, we determined the viability of Nipah virus (strain Bangladesh/200401066) in artificial palm sap. At 22°C virus titers remained stable for at least 7 days, thus potentially allowing food-borne transmission. Next, we modeled food-borne Nipah virus infection by supplying Syrian hamsters with artificial palm sap containing Nipah virus. Drinking of 5×10⁸ TCID₅₀ of Nipah virus resulted in neurological disease in 5 out of 8 hamsters, indicating that food-borne transmission of Nipah virus can indeed occur. In comparison, intranasal (i.n.) inoculation with the same dose of Nipah virus resulted in lethal respiratory disease in all animals. In animals infected with Nipah virus via drinking, virus was detected in respiratory tissues rather than in the intestinal tract. Using fluorescently labeled Nipah virus particles, we showed that during drinking, a substantial amount of virus is deposited in the lungs, explaining the replication of Nipah virus in the respiratory tract of these hamsters. Besides the ability of Nipah virus to infect hamsters via the drinking route, Syrian hamsters infected via that route transmitted the virus through direct contact with naïve hamsters in 2 out of 24 transmission pairs. Although these findings do not directly prove that date palm sap contaminated with Nipah virus by bats is the origin of Nipah virus outbreaks in Bangladesh, they provide the first experimental support for this hypothesis. Understanding the Nipah virus transmission cycle is essential for preventing

  6. Diet-induced dyslipidemia impairs reverse cholesterol transport in hamsters.

    Science.gov (United States)

    Tréguier, Morgan; Briand, François; Boubacar, Adamou; André, Agnès; Magot, Thierry; Nguyen, Patrick; Krempf, Michel; Sulpice, Thierry; Ouguerram, Khadija

    2011-09-01

    Reverse cholesterol transport (RCT) is an anti-atherogenic process by which cholesterol is effluxed from peripheral tissues by high-density lipoprotein (HDL) and returned to the liver for excretion into the bile and faeces. Dyslipidemia is thought to impair RCT through higher triglyceride-rich lipoprotein (TRL), low HDL-cholesterol and higher activity of cholesteryl ester transfer protein (CETP), which transfers cholesteryl esters from HDL to TRL for further hepatic uptake. As CETP pathway would represent a major route in human RCT, we therefore investigated whether diet-induced dyslipidemia impairs RCT in hamster, a CETP-expressing species. Golden Syrian hamsters were fed a chow or chow+0·3% cholesterol diet over 4 weeks. Biochemical parameters and in vivo VLDL-triglycerides secretion (Triton WR-1339 injection) were then measured. In vitro macrophage cholesterol efflux was measured, and in vivo macrophage-to-faeces RCT was also assessed after an intraperitoneal injection of (3) H-cholesterol-labelled hamster primary macrophages. Cholesterol-enriched diet increased plasma total cholesterol (144%), triglycerides (101%), VLDL-triglycerides secretion (175%), CETP activity (44%) and reduced HDL-cholesterol/total cholesterol ratio by 20% (P diet significantly increased hepatic total cholesterol and triglycerides by 459 and 118% and increased aortic total cholesterol content by 304%. In vitro cholesterol efflux from macrophages to plasma was significantly reduced by 25% with plasma from cholesterol-fed hamsters. In vivo RCT experiments showed a significant 75% reduction of macrophage-derived cholesterol faecal excretion in cholesterol-fed hamsters. Overall, these data demonstrate that diet-induced dyslipidemia severely impairs in vivo RCT in hamsters. © 2011 The Authors. European Journal of Clinical Investigation © 2011 Stichting European Society for Clinical Investigation Journal Foundation.

  7. The thalamic intergeniculate leaflet modulates photoperiod responsiveness in Siberian hamsters.

    Science.gov (United States)

    Freeman, David A; Dhandapani, Krishnan M; Goldman, Bruce D

    2004-11-26

    Siberian hamsters are seasonal breeders that use changes in day length to synchronize their reproductive effort with those times of the year most favorable for successful reproduction. The ability of Siberian hamsters to measure and respond to changes in day length depends upon accurate photoentrainment of the circadian clock in the suprachiasmatic nucleus (SCN) of the hypothalamus. Two pathways have been characterized through which entraining stimuli reach the SCN: the retinohypothalamic tract (RHT), which transmits light information from the retinae, and the geniculohypothalamic tract (GHT) from the intergeniculate leaflet of the thalamus (IGL), which is involved in transmitting both photic and nonphotic cues. Ablating the IGL/GHT results in only modest alterations in entrainment to static day lengths and fails to interfere with seasonal responses induced by transfer from static long day to static short day lengths. Because several studies suggest that the IGL may be involved in tracking the time of dusk and dawn, we sought to determine whether an intact IGL is necessary for hamsters to respond to a simulated natural photoperiod (SNP) in which the time of dusk and dawn gradually changes in a pattern approximating the rate of change in day length that occurs during autumn at the latitude this species inhabits in nature. The results indicate that neurochemical lesions of the IGL alter both the pattern of circadian entrainment and photoperiodic responsiveness of Siberian hamsters to an SNP. Both intact and IGL-lesioned hamsters exhibited testicular regression in shortening day lengths, but only IGL-intact hamsters exhibited seasonal pelage molt.

  8. Anthelmintic, anti-inflammatory and antioxidant effects of Garcinia mangostana extract in hamster opisthorchiasis.

    Science.gov (United States)

    Aukkanimart, Ratchadawan; Boonmars, Thidarut; Sriraj, Pranee; Songsri, Jiraporn; Laummaunwai, Porntip; Waraasawapati, Sakda; Boonyarat, Chantana; Rattanasuwan, Panaratana; Boonjaraspinyo, Sirintip

    2015-07-01

    Administration of praziquantel for treatment of liver fluke infection may affect the host, with mild and severe effects after treatment caused by host immune response. Therefore, we focused on the antioxidant property, inflammatory and anthelmintic effects of the traditional folk medicine, G. mangostana pericarp extract, in hamster opisthorchiasis. Syrian hamsters were divided into four groups: normal (control) (N); administered G. mangostana alone (GM); infected with Opisthorchis viverrini alone (OV); and infected with O. viverrini and administered G. mangostana extract for 1.5 months (OVGM). Hamster livers were collected 45 days after infection to determine histopathological changes, i.e. aggregation of inflammatory cells. The morphology of adult O. viverrini (body size and sizes of reproductive organs) was analyzed, as well as worm burden, eggs per worm and eggs per gram of feces. Toxicity was tested by kidney function (blood urea nitrogen and creatinine); the results demonstrated that G. mangostana had no renal toxic effect. ABTS radical-scavenging assay indicated that the extract had antioxidant property. Reduction in aggregation of inflammatory cells surrounding the hepatic bile duct, especially at the hilar region, was found in the OVGM group. Worm burden was similar in both infected groups (treated or untreated with G. mangostana), but the average size of adults in the OV group was larger than in the OVGM group; moreover, eggs per worm and eggs per gram of feces were also comparatively higher. The present study suggests that G. mangostana extract possesses anti-inflammatory and antioxidant properties and can interfere with parasite development by affecting adult size and egg production. This may be useful for controlling the spread of OV infection and other parasites in endemic areas. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. 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

  10. Leishmania donovani Infection Induces Anemia in Hamsters by Differentially Altering Erythropoiesis in Bone Marrow and Spleen

    Science.gov (United States)

    Lafuse, William P.; Story, Ryan; Mahylis, Jocelyn; Gupta, Gaurav; Varikuti, Sanjay; Steinkamp, Heidi; Oghumu, Steve; Satoskar, Abhay R.

    2013-01-01

    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 cytokine

  11. Enhanced efficacy of CTLA-4 fusion anti-caries DNA vaccines in gnotobiotic hamsters.

    Science.gov (United States)

    Zhang, Feng; Li, Yu-hong; Fan, Ming-wen; Jia, Rong; Xu, Qing-an; Guo, Ji-hua; Yu, Fei; Tian, Qi-wei

    2007-08-01

    To evaluate the comparative immunogenicity and protective efficacy of the cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) fusion anti-caries DNA vaccines pGJA-P/VAX1, pGJA-P, and non-fusion anti-caries DNA construct pGLUA-P in hamsters. In addition, the ability of CTLA-4 to target pGJA-P/VAX1-encoding antigen to dendritic cells was tested in vitro. All DNA constructs contain genes encoding the A-P regions of a cell surface protein (PAc) and the glucan binding (GLU) domain of glucosyltransferases (GTFs) of cariogenic organism Streptococcus mutans. Human dendritic cells were mixed with the CTLA-4-Ig-GLU-A-P protein expressed by pGJA-P/VAX1-transfected cells and analyzed by flow cytometry. Gnotobiotic hamsters were immunized with anti-caries DNA vaccines by intramuscular injection or intranasal administration. Antibody responses to a representative antigen PAc were assayed by ELISA, and caries protection was evaluated by Keyes caries scores. A flow cytometric analysis demonstrated that CTLA-4-Ig-GLU-A-P protein was capable of binding to human dendritic cells. pGJA-P/VAX1 and pGJA-P induced significantly higher specific salivary and serum anti-PAc antibody responses than pGLUA-P. Significantly fewer caries lesions were also observed in hamsters immunized with pGJA-P/VAX1 and pGJA-P. There was no significant difference in the anti-PAc antibody level or caries scores between pGJA-P/VAX1 and pGJA-P-immunized groups. Antigen encoded by CTLA-4 fusion anti-caries DNA vaccine pGJA-P/VAX1 could specifically bind to human dendritic cells through the interaction of CTLA-4 and B7 molecules. Fusing antigen to CTLA-4 has been proven to greatly enhance the immunogenicity and protective efficacy of anti-caries DNA vaccines.

  12. Neonatal monosodium glutamate treatment counteracts circadian arrhythmicity induced by phase shifts of the light-dark cycle in female and male Siberian hamsters.

    Science.gov (United States)

    Prendergast, Brian J; Onishi, Kenneth G; Zucker, Irving

    2013-07-12

    Studies of rats and voles suggest that distinct pathways emanating from the anterior hypothalamic-retrochiasmatic area and the mediobasal hypothalamic arcuate nucleus independently generate ultradian rhythms (URs) in hormone secretion and behavior. We evaluated the hypothesis that destruction of arcuate nucleus (ARC) neurons, in concert with dampening of suprachiasmatic nucleus (SCN) circadian rhythmicity, would compromize the generation of ultradian rhythms (URs) of locomotor activity. Siberian hamsters retain-->of both sexes treated neonatally with monosodium glutamate (MSG) that destroys ARC neurons were subjected in adulthood to a circadian disrupting phase-shift protocol (DPS) that produces SCN arrhythmia. MSG treatments induced hypogonadism and obesity, retain-->and markedly reduced the size of the optic chiasm and optic nerves. MSG-treated hamsters exhibited normal entrainment to the light-dark cycle, but MSG treatretain-->ment counteracted the circadian arrhythmicity induced by the DPS protocol: only 6% of retain-->MSG-treated hamsters exhibited circadian arrhythmia, whereas 50% of control hamsters were circadian disrupted. In MSG-treated hamsters that retained circadian rhythmicity after DPS treatment, quantitative parameters of URs appeared normal, but in the two MSG-treated hamsters that became circadian arrhythmic after DPS, both dark-phase and light-phase URs were abolished. Although preliminary, these data are consistent with reports in voles suggesting that the combined disruption of SCN and ARC function impairs the expression of behavioral URs. The data also suggest that light thresholds for entrainment of circadian rhythms may be lower than those required to disrupt circadian organization. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. The Hamster Buccal Pouch Model of Oral Carcinogenesis.

    Science.gov (United States)

    Nagini, Siddavaram; Kowshik, Jaganathan

    2016-01-01

    The hamster buccal pouch (HBP) carcinogenesis model is one of the most well-characterized animal tumor models used as a prelude to investigate multistage oral carcinogenesis and to assess the efficacy of chemointervention. Hamster buccal pouch carcinomas induced by 7,12-dimethylbenz[a]anthracene (DMBA) show extensive similarities to human oral squamous cell carcinomas. The HBP model offers a number of advantages including a simple and predictable tumor induction procedure, easy accessibility for examination and follow-up of lesions, and reproducibility. This model can be used to test both chemopreventive and chemotherapeutic agents.

  14. Genotoxic activity of nitrilotriacetic acid in Chinese hamster cells.

    Science.gov (United States)

    Modesti, D; Tanzarella, C; Degrassi, F

    1995-05-01

    Nitrilotriacetic acid (NTA), a chelating agent, was tested for its ability to induce chromosomal damage in Chinese hamster cells. The chemical was shown to exert a weak genotoxic activity increasing the frequency of micronuclei after prolonged treatments. The analysis of kinetochore containing-micronuclei showed that NTA prevailingly induces chromosomal aberrations as compared to chromosome loss in hamster cells. Furthermore, immunostaining with an alpha-tubulin antibody showed clear alterations in the interphase microtubule network of cells treated for 24 h with 3 mM NTA. The microtubule effects of the chemical may be partly responsible for its cytotoxic effects.

  15. 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.

  16. Reconstruction of the eruptive activity on the NE sector of Stromboli volcano: timing of flank eruptions since 15 ka

    NARCIS (Netherlands)

    Calvari, S.; Branca, S.; Corsaro, R.A.; De Beni, E.; Miraglia, L.; Norini, G.; Wijbrans, J.R.; Boschi, E.

    2011-01-01

    A multidisciplinary geological and compositional investigation allowed us to reconstruct the occurrence of flank eruptions on the lower NE flank of Stromboli volcano since 15 ka. The oldest flank eruption recognised is Roisa, which occurred at ~15 ka during the Vancori period, and has transitional

  17. Flanking sound insulation of wood frame assemblies with high axial and lateral load bearing capacity

    National Research Council Canada - National Science Library

    Zeitler, Berndt William; Schoenwald, Stefan; King, Frances

    2013-01-01

    As part of a multidisciplinary research project to develop design solutions for mid-rise wooden buildings for the Canadian market, a comprehensive study was conducted on the flanking sound insulation...

  18. Magnocellular involvement in flanked-letter identification relates to the allocation of attention

    NARCIS (Netherlands)

    Omtzigt, D.; Hendriks, A.W.C.J.

    2004-01-01

    To verify the hypothesis that the magnocellular system is important to flanked-letter identification [Neuropsychologia 40 (2002) 1881] because it subserves attention allocation, we conducted three letter-naming experiments in which we manipulated magnocellular involvement (colour vs. luminance

  19. Efficient gene targeting in golden Syrian hamsters by the CRISPR/Cas9 system.

    Directory of Open Access Journals (Sweden)

    Zhiqiang Fan

    Full Text Available The golden Syrian hamster is the model of choice or the only rodent model for studying many human diseases. However, the lack of gene targeting tools in hamsters severely limits their use in biomedical research. Here, we report the first successful application of the CRISPR/Cas9 system to efficiently conduct gene targeting in hamsters. We designed five synthetic single-guide RNAs (sgRNAs--three for targeting the coding sequences for different functional domains of the hamster STAT2 protein, one for KCNQ1, and one for PPP1R12C--and demonstrated that the CRISPR/Cas9 system is highly efficient in introducing site-specific mutations in hamster somatic cells. We then developed unique pronuclear (PN and cytoplasmic injection protocols in hamsters and produced STAT2 knockout (KO hamsters by injecting the sgRNA/Cas9, either in the form of plasmid or mRNA, targeting exon 4 of hamster STAT2. Among the produced hamsters, 14.3% and 88.9% harbored germline-transmitted STAT2 mutations from plasmid and mRNA injection, respectively. Notably, 10.4% of the animals produced from mRNA injection were biallelically targeted. This is the first success in conducting site-specific gene targeting in hamsters and can serve as the foundation for developing other genetically engineered hamster models for human disease.

  20. Efficient gene targeting in golden Syrian hamsters by the CRISPR/Cas9 system.

    Science.gov (United States)

    Fan, Zhiqiang; Li, Wei; Lee, Sang R; Meng, Qinggang; Shi, Bi; Bunch, Thomas D; White, Kenneth L; Kong, Il-Keun; Wang, Zhongde

    2014-01-01

    The golden Syrian hamster is the model of choice or the only rodent model for studying many human diseases. However, the lack of gene targeting tools in hamsters severely limits their use in biomedical research. Here, we report the first successful application of the CRISPR/Cas9 system to efficiently conduct gene targeting in hamsters. We designed five synthetic single-guide RNAs (sgRNAs)--three for targeting the coding sequences for different functional domains of the hamster STAT2 protein, one for KCNQ1, and one for PPP1R12C--and demonstrated that the CRISPR/Cas9 system is highly efficient in introducing site-specific mutations in hamster somatic cells. We then developed unique pronuclear (PN) and cytoplasmic injection protocols in hamsters and produced STAT2 knockout (KO) hamsters by injecting the sgRNA/Cas9, either in the form of plasmid or mRNA, targeting exon 4 of hamster STAT2. Among the produced hamsters, 14.3% and 88.9% harbored germline-transmitted STAT2 mutations from plasmid and mRNA injection, respectively. Notably, 10.4% of the animals produced from mRNA injection were biallelically targeted. This is the first success in conducting site-specific gene targeting in hamsters and can serve as the foundation for developing other genetically engineered hamster models for human disease.

  1. Evaluation of Flanking Noise Transmission within Periodically Distributed Lightweight Beam Elements

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal; Andersen, Lars Vabbersgaard; Sorokin, Sergey

    2012-01-01

    . Two different theoretical methods are taken into consideration to evaluate flanking noise transmission within the beam structure: The finite-element method (FEM) and a Floquet theory approach. Research is carried out regarding the effects of periodicity in a wide range of frequencies from 0 to 300 Hz...... are thoroughly investigated and compared. The findings of the analysis are applicable in the design of structures such as buildings, ships and aircrafts, regarding minimization of flanking noise transmission....

  2. Cloning of a hamster anti-mouse CD79B antibody sequences and identification of a new hamster immunoglobulin lambda constant IGLC gene region.

    Science.gov (United States)

    Haggart, Ryan; Perera, Jason; Huang, Haochu

    2013-06-01

    Anti-CD79 antibodies have been effective at targeting B cell lymphoma cells and depleting B cells in animal models. In order to engineer recombinant antibodies with additional effector functions in mice, we cloned and sequenced the full-length cDNAs of the heavy and light chain of a hamster anti-mouse CD79B antibody. Although hamster antibodies represent a unique source of monoclonal antibodies against mouse, rat, and human antigens, sequence information of hamster immunoglobulins (IG) is sparse. Here, we report a new hamster (Cricetulus migratorius) IG lambda constant (IGLC) gene region that is most homologous to mouse IGLC2 and IGLC3.

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

    African Journals Online (AJOL)

    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.

  4. Characterisation of monoclonal antibodies specific for hamster leukocyte differentiation molecules.

    Science.gov (United States)

    Rees, Jennifer; Haig, David; Mack, Victoria; Davis, William C

    2017-01-01

    Flow cytometry was used to identify mAbs that recognize conserved epitopes on hamster leukocyte differentiation molecules (hLDM) and also to characterize mAbs developed against hLDM. Initial screening of mAbs developed against LDMs in other species yielded mAbs specific for the major histocompatibility (MHC) II molecule, CD4 and CD18. Screening of sets of mAbs developed against hLDM yielded 22 new mAbs, including additional mAbs to MHC II molecules and mAbs that recognize LDMs expressed on all leukocytes, granulocytes, all lymphocytes, all T cells, a subset of T cells, or on all B cells. Based on comparison of the pattern of expression of LDMs expressed on all hamster leukocytes with the patterns of expression of known LDMs in other species, as detected by flow cytometry (FC), four mAbs are predicted to recognize CD11a, CD44, and CD45. Cross comparison of mAbs specific for a subset of hamster T cells with a cross reactive mAb known to recognize CD4 in mice and one recognising CD8 revealed they recognize CD4. The characterization of these mAbs expands opportunities to use hamsters as an additional model species to investigate the mechanisms of immunopathogenesis of infectious diseases. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  5. 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...

  6. Biodynamics of cholesterol and bile acids in the lithiasic hamster.

    Science.gov (United States)

    Khallou, J; Riottot, M; Parquet, M; Verneau, C; Lutton, C

    1991-11-01

    By using the isotopic equilibrium method in the young male Syrian hamster, the rates of cholesterol turnover processes, i.e. dietary cholesterol absorption, cholesterol synthesis, cholesterol excretion in the faeces and urine and cholesterol transformation into bile acids, were determined in the hamster receiving a control (C) or a lithogenic diet (L) for 7 weeks. At the end of this period the gall bladder of all animals in group L contained cholesterol gallstones. The coefficient of dietary cholesterol absorption was reduced by 26%, cholesterol synthesis and cholesterol faecal excretion were twofold higher in group L than in group C. Bile acid content in the small intestine was diminished in group L, but bile acid composition was similar in the two groups. The increase in cholesterogenesis in lithiasic animals essentially took place in the liver. Bile acid biosynthesis did not significantly differ in the two groups, but represented only 35% of total cholesterol input (dietary absorption + internal secretion) in group L v. 52% in group C. Thus, in the lithiasic hamster, hepatic synthesis of cholesterol and bile acids are not coupled. The molar percentage of cholesterol in bile was twofold higher in group L than in group C but those of bile acids and of phospholipids were not modified. In the lithiasic hamster the specific activity of biliary cholesterol was similar to that in plasma and liver. Consequently, biliary cholesterol does not derive directly from cholesterol newly synthesized in the liver but from hepatic cholesterol rapidly exchangeable with plasma cholesterol.

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

    NARCIS (Netherlands)

    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

  8. 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

  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 representative left in Africa of the subfamily Cricetinae (Davis 1962). It has been used in Medical Research on poliomyelitis, benign histoplasmosis, ...

  10. 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

  11. Rudimentary coronary artery in Syrian hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Durán, A C; Arqué, J M; Fernández, B; Fernández, M C; Fernández-Gallego, T; Rodríguez, C; Sans-Coma, V

    2009-08-01

    Congenital underdevelopment of one or more main branches of the coronary arteries has been reported in man, but not in non-human mammals. In man, this defective coronary artery arrangement may cause myocardial ischaemia and even sudden death. The main goal of this study was to describe the coronary artery distribution patterns associated with the presence of a markedly underdeveloped (rudimentary) coronary artery in Syrian hamsters. Moreover, an attempt was made to explain the morphogenesis of these patterns, according to current knowledge on coronary artery development. Eleven affected hamsters belonging to a laboratory inbred family were examined by means of internal casts of the heart, great arterial trunks and coronary arteries. The aortic valve was tricuspid (normal) in seven hamsters and bicuspid in the other four. A rudimentary coronary artery arose from the right side of the aortic valve in four specimens, from the left side of the aortic valve in a further three, and from the dorsal aortic sinus in the remaining four. In all cases, a second, well-developed coronary artery provided for all the coronary blood flow. Except for the existence of a rudimentary coronary artery, the present anomalous coronary artery distribution patterns are similar to coronary artery patterns reported in Syrian hamsters, dogs and humans in association with a solitary coronary ostium in aorta. We suggest that an unusual prolonged time interval in the development of the embryonic coronary stems might be a key factor in the formation of coronary arteries displaying significantly dissimilar developmental degrees.

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Localization, accumulation, and toxic effects of mercuric chloride on the reproductive axis of the female hamster

    Energy Technology Data Exchange (ETDEWEB)

    Lamperti, A.A.; Printz, R.H.

    1974-01-01

    Experiments were performed to determine the mechanism for the effects of mercuric chloride on the reproductive system of the hamster. Tissue levels of mercury were determined in animals which were treated with daily subcutaneous doses of saline, 1 mg of HgCl/sub 2/, or 1 mg of HgCl/sub 2/ and 50 mg of N-acetyl-DL-penicillamine (NAP), throughout one 4-day estrous cycle. The relations between concentration of mercury in several organs were found to be kidney > liver > anterior pituitary > ovary > blood > uterus > hypothalamus > cerebral cortex. Animals which were injected with HgCl/sub 2/ and NAP had significantly less (p < 0.001) mercury than animals treated with HgCl/sub 2/ alone in all tissues except the cerebral cortex. Tissues from animals which were injected daily with 12 ..mu..Ci of /sup 203/HgCl/sub 2/ and 1 mg of HgCl/sub 2/ were prepared for radioautography. In the ovary, mercury was more concentrated in the corpora lutea than the follicles of interstitium. Mercury was also found lining the sinusoids of the pituitary and in some of the neurons of the arcuate nucleus of the hypothalamus. Explanations for possible alterations in gonadotropin secretion are discussed. When hamsters were given a total of 3 or 4 mg of HgCl/sub 2/ during the first cycle, 60% of the animals did not ovulate by Day 1 of the third cycle. 9 references, 8 figures, 2 tables.

  14. Cross-species fertilization: the hamster egg receptor, Juno, binds the human sperm ligand, Izumo1.

    Science.gov (United States)

    Bianchi, Enrica; Wright, Gavin J

    2015-02-05

    Fertilization is the culminating event in sexual reproduction and requires the recognition and fusion of the haploid sperm and egg to form a new diploid organism. Specificity in these recognition events is one reason why sperm and eggs from different species are not normally compatible. One notable exception is the unusual ability of zona-free eggs from the Syrian golden hamster (Mesocricetus auratus) to recognize and fuse with human sperm, a phenomenon that has been exploited to assess sperm quality in assisted fertility treatments. Following our recent finding that the interaction between the sperm and egg recognition receptors Izumo1 and Juno is essential for fertilization, we now demonstrate concordance between the ability of Izumo1 and Juno from different species to interact, and the ability of their isolated gametes to cross-fertilize each other in vitro. In particular, we show that Juno from the golden hamster can directly interact with human Izumo1. These data suggest that the interaction between Izumo1 and Juno plays an important role in cross-species gamete recognition, and may inform the development of improved prognostic tests that do not require the use of animals to guide the most appropriate fertility treatment for infertile couples.

  15. Effect of bovine lactoferrin in a therapeutic hamster model of hepatic amoebiasis.

    Science.gov (United States)

    Ordaz-Pichardo, Cynthia; León-Sicairos, Nidia; Hernández-Ramírez, Verónica Ivonne; Talamás-Rohana, Patricia; de la Garza, Mireya

    2012-06-01

    Entamoeba histolytica is the causative agent of amoebiasis, a disease that produces dysentery as a result of the perforation of the large intestine. This parasite often invades other organs, primarily the liver, leading to an amoebic liver abscess (ALA), which can cause death. Metronidazole is the drug of choice for the treatment of ALA; however, it produces toxic side effects in patients. Lactoferrin (Lf) is a glycoprotein of the innate immune response that sequesters iron in the mucosae. Lf possesses immune-regulatory properties, such as antiinflammatory and antioxidant activities. Moreover, the microbicidal activity of apoLf, which lacks bound iron, has been shown. In this study, we evaluated the therapeutic effect of bovine Lf (bLf) against ALA in a model of hepatic amoebiasis in hamsters. Interestingly, hamsters treated intragastrically with Lf (2.5 mg/100 g mass) over a period of 8 days showed no clinical signs of disease and ALA was effectively decreased, with only 0.63% detectable lesion, compared with 63% in untreated animals. Furthermore, liver function and blood cells approached normal levels among those receiving bLf treatment. These results suggest that bLf may aid in the therapy of amoebiasis, likely without producing undesirable effects in patients.

  16. Tumor incidence was not related to the thickness of visceral pleural in female Syrian hamsters intratracheally administered amphibole asbestos or manmade fibers.

    Science.gov (United States)

    Adachi, S; Kawamura, K; Kimura, K; Takemoto, K

    1992-06-01

    Histological observations were performed on female Syrian hamsters 2 years after the intratracheal administration of amphibole asbestos, amosite, and crocidolite to evaluate the tumorigenicity of six types of fine manmade fibers (reported previously). A mesothelioma and a lung tumor were induced in 20 animals administered amosite, but no tumors were found in the crocidolite group. Because this incidence is not higher than that of manmade fibers, such as basic magnesium sulfate fiber [9 tumor-bearing hamsters in 20 hamsters (9/20)], metaphosphate fiber (5/20), calcium sulfate fiber (3/20), and fiberglass (2/20), it is suggested that some types of manmade fibers have a greater ability than asbestos to induce tumors. Moreover, as a specific observation in manmade fiber groups, tumors were induced at intracelial organs rather than at the pleural cavity. On the other hand, the average thickness of visceral pleura was higher in all asbestos and manmade fiber groups than in the control (2.9 microns), for instance, 36.95 microns in potassium titanate fiber group, 15.90 microns crocidolite group, 13.00 microns basic magnesium sulfate fiber group, and 10.45 microns in the rockwool group. Although both pleural thickening and mesothelioma are known as peculiar lesions in asbestos-exposed people, it might also be suggested that these lesions could be induced by different mechanisms from the result that there was no relation between the pleural thickening and mesothelioma incidence in hamsters.

  17. The association between maternal hydronephrosis and acute flank pain during pregnancy: a prospective pilot-study.

    Science.gov (United States)

    Farr, Alex; Ott, Johannes; Kueronya, Verena; Margreiter, Markus; Javadli, Elchin; Einig, Sabrina; Husslein, Peter W; Bancher-Todesca, Dagmar

    2017-10-01

    Maternal hydronephrosis may cause flank pain during pregnancy. We aimed to investigate the association between maternal hydronephrosis and flank pain intensity. From 2014 to 2015, all consecutive women with singleton pregnancies, who presented at our tertiary center due to acute flank pain, were prospectively evaluated by renal ultrasonography and pain questionnaires. A visual analogue scale was used to assess pain intensity. The study had 90% power to detect a significant correlation between hydronephrosis and flank pain (Spearman's test). A total of 51 consecutive women with left-sided (13.7%), right-sided (64.7%) or bilateral (21.6%) pain were enrolled. The mean gestational age of these women, who presented due to their pain, was 27.5 ± 6.8 weeks at the time of consultation. The mean VAS score was 7.6 ± 2.2. In 43/51 (84.3%) women, hydronephrosis was found on renal sonograms. No correlation was found between the grade of hydronephrosis and pain intensity (p = 0.466; r= -0.28). Women delivered at a mean gestational age of 38.1 ± 2.4 weeks and their infants had a mean birthweight of 3138 ± 677 g. Hydronephrosis is a common finding among pregnant women with acute flank pain. The grade of hydronephrosis does not affect pain intensity. This study suggests normal pregnancy outcomes in these women.

  18. Heat and cold acclimation in helium-cold hypothermia in the hamster.

    Science.gov (United States)

    Musacchia, X. J.

    1972-01-01

    A study was made of the effects of acclimation of hamsters to high (34-35 C) and low (4-5 C) temperatures for periods up to 6 weeks on the induction of hypothermia in hamsters. Hypothermia was achieved by exposing hamsters to a helox mixture of 80% helium and 20% oxygen at 0 C. Hypothermic induction was most rapid (2-3 hr) in heat-acclimated hamsters and slowest (6-12 hr) in cold-acclimated hamsters. The induction period was intermediate (5-8 hr) in room temperature nonacclimated animals (controls). Survival time in hypothermia was relatable to previous temperature acclimations. The hypothesis that thermogenesis in cold-acclimated hamsters would accentuate resistance to induction of hypothermia was substantiated.

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

    Science.gov (United States)

    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.

  20. Explosive eruption, flank collapse and megatsunami at Tenerife ca. 170 ka

    Science.gov (United States)

    Paris, Raphaël; Bravo, Juan J. Coello; González, María E. Martín; Kelfoun, Karim; Nauret, François

    2017-05-01

    Giant mass failures of oceanic shield volcanoes that generate tsunamis potentially represent a high-magnitude but low-frequency hazard, and it is actually difficult to infer the mechanisms and dynamics controlling them. Here we document tsunami deposits at high elevation (up to 132 m) on the north-western slopes of Tenerife, Canary Islands, as a new evidence of megatsunami generated by volcano flank failure. Analyses of the tsunami deposits demonstrate that two main tsunamis impacted the coasts of Tenerife 170 kyr ago. The first tsunami was generated during the submarine stage of a retrogressive failure of the northern flank of the island, whereas the second one followed the debris avalanche of the subaerial edifice and incorporated pumices from an on-going ignimbrite-forming eruption. Coupling between a massive retrogressive flank failure and a large explosive eruption represents a new type of volcano-tectonic event on oceanic shield volcanoes and a new hazard scenario.

  1. Mitigation of Flanking Noise Transmission in Periodic Structures of Lightweight Elements

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal

    through structural junctions and radiates into neighbouring rooms. To diminish the flanking transmission of sound, frames are usually designed with single or double studs or constructed with layers of foam or another viscoelastic material. This thesis is investigating the behaviour of flanking noise...... transmission in periodic structures of lightweight elements by employing various numerical, analytical and experimental methods. At first, three dimensional finite-element (FE) models of a Z-shaped lightweight panel structure based on various frame designs, inclusion of air and structural coupling between...... elements are considered for describing flanking noise transmission through panels. It is assumed that the ribs are fully fixed to the plates in case of various frame designs, and a parametric study is carried out on the centre panel with regard to various spacing between the ribs. Solid finite elements...

  2. Explosive eruption, flank collapse and megatsunami at Tenerife ca. 170 ka.

    Science.gov (United States)

    Paris, Raphaël; Bravo, Juan J Coello; González, María E Martín; Kelfoun, Karim; Nauret, François

    2017-05-15

    Giant mass failures of oceanic shield volcanoes that generate tsunamis potentially represent a high-magnitude but low-frequency hazard, and it is actually difficult to infer the mechanisms and dynamics controlling them. Here we document tsunami deposits at high elevation (up to 132 m) on the north-western slopes of Tenerife, Canary Islands, as a new evidence of megatsunami generated by volcano flank failure. Analyses of the tsunami deposits demonstrate that two main tsunamis impacted the coasts of Tenerife 170 kyr ago. The first tsunami was generated during the submarine stage of a retrogressive failure of the northern flank of the island, whereas the second one followed the debris avalanche of the subaerial edifice and incorporated pumices from an on-going ignimbrite-forming eruption. Coupling between a massive retrogressive flank failure and a large explosive eruption represents a new type of volcano-tectonic event on oceanic shield volcanoes and a new hazard scenario.

  3. Experimental treatment with sodium stibogluconate of hamsters infected with Leishmania (Leishmania) chagasi and Leishmania (Leishmania) amazonensis

    OpenAIRE

    Elizabeth M. de Figueiredo; Silva,Jaime Costa e; Brazil,Reginaldo P

    1999-01-01

    The present paper reports the experimental treatment of hamsters infected with Leishmania chagasi and Leishmania amazonensis with sodium stibogluconate (20mg/kg/day x 20 days). Only with L. chagasi did the treatment result in the complete elimination of parasites from the spleen. However, no parasitological cure was achieved in hamsters infected with L. amazonensis.O presente trabalho é um relato do tratamento experimental de hamsters infectado com Leishmania chagasi e Leishmania amazonensis ...

  4. Cell-Mediated Cytotoxicity Toward Measles Virus-Infected Target Cells in Randomly Bred Syrian Hamsters

    OpenAIRE

    Cremer, Natalie E.; O'Keefe, Beatrice; Hagens, Shirley J.; Diggs, Janice

    1982-01-01

    Cell-mediated cytotoxicity (CMC) toward measles virus-infected cells was studied by a 51Cr release assay with spleen cells from hamsters inoculated with measles virus (strain Lec) or control antigen and with spleen cells from normal hamsters. Spleen cells from measles virus-inoculated hamsters showed greater CMC toward infected than toward noninfected target cells (designated specific CMC). Specific CMC was maximal 7 days after virus inoculation and was declining by 9 to 10 days. Effector cel...

  5. Simulation of flanking transmission in super-light structures for airborne and impact sound

    DEFF Research Database (Denmark)

    Christensen, Jacob Ellehauge; Hertz, Kristian Dahl; Brunskog, Jonas

    2012-01-01

    Super-light structures are an invention based on combining lightweight concrete with normal concrete for better structural performance and lighter structures. The overall principle is based on load carrying arches of a normal concrete stabilised and protected from fire by a light-aggregate concrete....... In the flanking transmission analysis the influence of a large array of different flanking walls, structural connection details, room size and floor constructions, all typical or desirable for common multi-storey residential constructions, have been investigated. The results form a basis for guidelines on how...

  6. Leukotriene inhibition in hamster periodontitis. A histochemical and morphometric study

    Directory of Open Access Journals (Sweden)

    B. Baroukh

    1992-01-01

    Full Text Available The effects of leukotriene (LT inhibition on gingival and adjacent bone compartments were assessed by using phenidone (100 mg/kg/d and ketoconazole (50 mg/kg/d given for 4 weeks to periodontitis-affected hamsters. In the gingiva the two agents significantly decreased PMNL recruitment and migration and increased the vascular lumen. At the bone level, they reduced significantly preosteoclast and osteoclast numbers but did not affect osteoclast activity. Phenidone had no action on periodontitis induced inhibition of bone formation; in contrast ketoconazole enhanced formation. As both phenidone and ketoconazole are unspecific LT inhibitors it cannot be ascertained that the effects observed were actually due to LT inhibition. However, phenidone and ketoconazole induced changes different from indomethacin used in previous studies to inhibit the cyclooxygenase pathway. These discrepancies suggest that LT inhibition occurred in the present study and that they participate in gingival inflammation and osteoclastic destruction during hamster periodontitis.

  7. Spontaneous fibrosarcoma in a Djungarian hamster (phodopus sungorus).

    Science.gov (United States)

    Kondo, Hirotaka; Onuma, Mamoru; Ito, Hidetoshi; Shibuya, Hisashi; Sato, Tsuneo

    2008-06-01

    A 1.5-y-old female Djungarian hamster (Phodopus sungorus) presented with a large subcutaneous mass surrounding the right shoulder. Radiography revealed dislocation of the right humeral articulation and osteolytic lesions of the right scapula. Histologically, the mass was composed of spindle to stellate cells arranged in fascicles interwoven with delicate collagen fibers, and neoplastic cells infiltrated the bone, skeletal muscle, and subcutaneous tissues. Neoplastic cells stained intensely positive for vimentin and negative for S100 protein, neurofilament, and desmin. A minority of neoplastic cells (10% to 20%) stained moderately for smooth muscle actin. The mass was diagnosed as a fibrosarcoma. Although fibrosarcomas are relatively common in dogs and cats, this is the first report of fibrosarcoma in a domestic Djungarian hamster.

  8. 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.

  9. Regulation of hamster sperm hyperactivation by extracellular Na.

    Science.gov (United States)

    Takei, Gen L; Fujinoki, Masakatsu

    2016-06-01

    Mammalian sperm motility has to be hyperactivated to be fertilization-competent. Hyperactivation is regulated by extracellular environment. Osmolality of mammalian semen is higher than that in female reproductive tract; however, the effect of them on hyperactivation has not been investigated. So we investigated the effect of osmotic environment on hyperactivation using hamster spermatozoa at first. Increase in the osmolality of the media (∼370 mOsm) by increasing the concentration of NaCl (∼150 mmol/L) caused the delay of the expression of hyperactivation. When NaCl concentration varied in the same range (75-150 mmol/L) whereas the osmolality was fixed at 370 mOsm by adding mannitol, the delay of hyperactivation occurred dependent on NaCl concentration. Increase in NaCl concentration also caused suppression of curvilinear velocity, bend angle, and sliding velocity of the flagellum at the onset of incubation, suggesting that NaCl concentration affect both activation and hyperactivation in hamster spermatozoa. Hamster sperm intracellular Ca(2+) concentration decreased as extracellular NaCl concentration increased, whereas membrane potential and intracellular pH were unaffected by extracellular NaCl concentration. SN-6 and SEA0400, inhibitors of Na(+)-Ca(2+) exchanger (NCX), increased intracellular Ca(2+) and accelerated hyperactivation in the presence of 150 mmol/L NaCl. Tyrosine phosphorylation on fibrous sheath proteins was unaffected by extracellular NaCl concentration. These results suggest that extracellular Na(+) suppresses hamster sperm hyperactivation by reducing intracellular Ca(2+) via an action of NCX in a tyrosine phosphorylation-independent manner. It seems that the removal of suppression by extracellular Na(+) leads to the expression of hyperactivated motility. © 2016 Society for Reproduction and Fertility.

  10. Photoperiodic Influences on Ultradian Rhythms of Male Siberian Hamsters

    Science.gov (United States)

    Prendergast, Brian J.; Zucker, Irving

    2012-01-01

    Seasonal changes in mammalian physiology and behavior are proximately controlled by the annual variation in day length. Long summer and short winter day lengths markedly alter the amplitude of endogenous circadian rhythms and may affect ultradian oscillations, but the threshold photoperiods for inducing these changes are not known. We assessed the effects of short and intermediate day lengths and changes in reproductive physiology on circadian and ultradian rhythms of locomotor activity in Siberian hamsters. Males were maintained in a long photoperiod from birth (15 h light/day; 15 L) and transferred in adulthood to 1 of 7 experimental photoperiods ranging from 14 L to 9 L. Decreases in circadian rhythm (CR) robustness, mesor and amplitude were evident in photoperiods ≤14 L, as were delays in the timing of CR acrophase and expansion of nocturnal activity duration. Nocturnal ultradian rhythms (URs) were comparably prevalent in all day lengths, but 15 L markedly inhibited the expression of light-phase URs. The period (τ’), amplitude and complexity of URs increased in day lengths ≤13 L. Among hamsters that failed to undergo gonadal regression in short day lengths (nonresponders), τ’ of the dark-phase UR was longer than in photoresponsive hamsters; in 13 L the incidence and amplitude of light-phase URs were greater in hamsters that did not undergo testicular regression. Day lengths as long as 14 L were sufficient to trigger changes in the waveform of CRs without affecting UR waveform. The transition from a long- to a short-day ultradian phenotype occurred for most UR components at day lengths of 12 L–13 L, thereby establishing different thresholds for CR and UR responses to day length. At the UR-threshold photoperiod of 13 L, differences in gonadal status were largely without effect on most UR parameters. PMID:22848579

  11. Circadian arrhythmia dysregulates emotional behaviors in aged Siberian hamsters

    Science.gov (United States)

    Prendergast, Brian J.; Onishi, Kenneth G.; Patel, Priyesh N.; Stevenson, Tyler J.

    2014-01-01

    Emotional behaviors are influenced by the circadian timing system. Circadian disruptions are associated with depressive-like symptoms in clinical and preclinical populations. Circadian rhythm robustness declines markedly with aging and may contribute to susceptibility to emotional dysregulation in aged individuals. The present experiments used a model of chronic circadian arrhythmia generated noninvasively, via a series of circadian-disruptive light treatments, to investigate interactions between circadian desynchrony and aging on depressive- and anxiety-like behaviors, and on limbic neuroinflammatory gene expression that has been linked with emotionality. We also examined whether a social manipulation (group housing) would attenuate effects of arrhythmia on emotionality. In aged (14-18 months of age) male Siberian hamsters, circadian arrhythmia increased behavioral despair and decreased social motivation, but decreased exploratory anxiety. These effects were not evident in younger (5-9 months of age) hamsters. Social housing (3-5 hamsters/cage) abolished the effects of circadian arrhythmia on emotionality. Circadian arrhythmia alone was without effect on hippocampal or cortical interleukin-1β (IL-1β) and indoleamine 2,3-dioxygenase (Ido) mRNA expression in aged hamsters, but social housing decreased hippocampal IL-1β and Ido mRNAs. The data demonstrate that circadian disruption can negatively impact affective state, and that this effect is pronounced in older individuals. Although clear associations between circadian arrhythmia and constitutive limbic proinflammatory activity were not evident, the present data suggest that social housing markedly inhibits constitutive hippocampal IL-1β and Ido activity, which may contribute to the ameliorating effects of social housing on a number of emotional behaviors. PMID:24333374

  12. Spontaneous Fibrosarcoma in a Djungarian Hamster (Phodopus sungorus)

    OpenAIRE

    Kondo, Hirotaka; ONUMA, Mamoru; Ito, Hidetoshi; Shibuya, Hisashi; Sato, Tsuneo

    2008-01-01

    A 1.5-y-old female Djungarian hamster (Phodopus sungorus) presented with a large subcutaneous mass surrounding the right shoulder. Radiography revealed dislocation of the right humeral articulation and osteolytic lesions of the right scapula. Histologically, the mass was composed of spindle to stellate cells arranged in fascicles interwoven with delicate collagen fibers, and neoplastic cells infiltrated the bone, skeletal muscle, and subcutaneous tissues. Neoplastic cells stained intensely po...

  13. Clozapine chronically suppresses alcohol drinking in Syrian golden hamsters

    Science.gov (United States)

    Chau, David T.; Gulick, Danielle; Xie, Haiyi; Dawson, Ree; Green, Alan I.

    2015-01-01

    Alcohol use disorder is common in patients with schizophrenia and is associated with poor clinical outcomes. Preliminary reports from our group and others suggest that the atypical antipsychotic clozapine may decrease alcohol use in these patients. We have previously shown that clozapine suppresses alcohol consumption for 9 days in Syrian golden hamsters. Here, we assessed the effects of clozapine on alcohol consumption in hamsters over a 27-day period, using a continuous access, 2-bottle (15% alcohol vs. water) protocol. Clozapine (4, 8, or 12 mg/kg/day, injected subcutaneously [s.c.]) dose-dependently suppressed alcohol drinking, while increasing food and water intake, and there was no tolerance within individual groups to this effect of clozapine over time. In a separate experiment, the effects of clozapine on sucrose and water drinking and food intake over a 9-day period were assessed. Clozapine (4, 8, or 12 mg/kg/day s.c.) failed to suppress sucrose (0.09 M), food, or water consumption at any time-point tested. In a related study, assessment of blood alcohol levels in hamsters indicated that blood alcohol levels were maintained within a narrow and moderate range (7–13 mg/dL), levels noted by others to produce physiologic effects in rodents. The ability of clozapine to suppress alcohol drinking in the hamster over an extended period of time without suppressing sucrose, water, or food consumption is consistent with preliminary reports indicating that clozapine limits frequent alcohol use, even producing abstinence in many patients with schizophrenia. PMID:19895824

  14. 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.

  15. The pathology of experimental Schistosoma curassoni infections in mice and hamsters.

    Science.gov (United States)

    Vercruysse, J; Fransen, J; Southgate, V R; Rollinson, D

    1986-11-01

    The histopathology of experimental Schistosoma curassoni infections in white mice and hamsters was studied. In mice, hepatic lesions were severe with characteristic extensive perilobular fibrosis and large perilobular granulomas throughout the parenchyma. Only a few granulomas were detected in the lung, small intestine, and rectum of mice. In hamsters, lesions in the liver were limited. Few granulomas were found but the giant cell reaction was pronounced. Lesions in the lung and small intestine were minimal. Many subserosal and submucosal epithelioid cell granulomas were in the colon and rectum of hamsters. Parasites were not detected in the bladder of either mice or hamsters.

  16. 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.

  17. Learned magnetic compass orientation by the Siberian hamster, Phodopus sungorus

    Energy Technology Data Exchange (ETDEWEB)

    Deutschlander, Mark E.; Freake, Michael J.; Borland, Christopher; Phillips, John B.; Madden, R C.; Anderson, Larry E.; Wilson, B W.

    2003-04-01

    Magnetic orientation has been demonstrated in Siberian hamsters, Phodopus sungorus. The behavior, using a nest building assay, shows a directional preference in nest position and appears in this animal to be a learned behavior. Hamsters were housed prior to testing in rectangular cages aligned along perpendicular axes. When subsequently tested in a radially-symmetrical arena, the hamsters positioned their nests in a bimodal distribution that coincided with the magnetic direction of the long-axis of the holding cages. In addition, results are presented that illustrate some of the factors that can influence behavioral responses to the magnetic field. In particular for P. sungorus, holding conditions prior to testing and the presence of non-magnetic cues may influence the strength and expression of magnetic orientation. Failure to consider these and other factors may help to explain why previous attempts to demonstrate magnetic orientation in a number of rodent species have failed or, when positive results have been obtained, have been difficult to replicate in other laboratories.

  18. 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.

  19. Isotretinoin-induced craniofacial malformations in humans and hamsters.

    Science.gov (United States)

    Willhite, C C; Hill, R M; Irving, D W

    1986-01-01

    Oral administration of 40-80 mg/d of isotretinoin (13-cis-retinoic acid, Ro 4-3780, Accutane) during the first month of human pregnancy can induce severe congenital malformation. The human Accutane dysmorphic syndrome includes rudimentary external ears, absent or imperforate auditory canals, a triangular microcephalic skull, cleft palate, depressed midface, and anomalies of the brain, jaw, and heart. Children who suffer from this syndrome have large occiputs with narrowing of the frontal bone. Microphthalmia is reported in two cases; notations are made about the orbits in three cases; and the fact that infants could not follow with their eyes is noted in three cases. A decrease in muscle tone is noted in six, cleft palate is present in four, and limb reduction defects are described in two. The cardiac malformations usually include overriding aorta, interrupted or hypoplastic aortic arch, and septation defects of atria and ventricles. There are at least two cases of abnormal origin of the subclavian arteries. Oral isotretinoin in the pregnant hamster also induces similar congenital malformations. A human case of isotretinoin-induced dysmorphia is presented and compared with other affected infants and affected hamsters. The metabolic fate and pharmacokinetic parameters of isotretinoin in humans and rodents are discussed in relation to the teratogenic response. The results suggest that humans are approximately 16 times more sensitive to the teratogenic effects of oral isotretinoin than are hamsters.

  20. Fusion primer and nested integrated PCR (FPNI-PCR): a new high-efficiency strategy for rapid chromosome walking or flanking sequence cloning

    Science.gov (United States)

    2011-01-01

    Background The advent of genomics-based technologies has revolutionized many fields of biological enquiry. However, chromosome walking or flanking sequence cloning is still a necessary and important procedure to determining gene structure. Such methods are used to identify T-DNA insertion sites and so are especially relevant for organisms where large T-DNA insertion libraries have been created, such as rice and Arabidopsis. The currently available methods for flanking sequence cloning, including the popular TAIL-PCR technique, are relatively laborious and slow. Results Here, we report a simple and effective fusion primer and nested integrated PCR method (FPNI-PCR) for the identification and cloning of unknown genomic regions flanked known sequences. In brief, a set of universal primers was designed that consisted of various 15-16 base arbitrary degenerate oligonucleotides. These arbitrary degenerate primers were fused to the 3' end of an adaptor oligonucleotide which provided a known sequence without degenerate nucleotides, thereby forming the fusion primers (FPs). These fusion primers are employed in the first step of an integrated nested PCR strategy which defines the overall FPNI-PCR protocol. In order to demonstrate the efficacy of this novel strategy, we have successfully used it to isolate multiple genomic sequences namely, 21 orthologs of genes in various species of Rosaceace, 4 MYB genes of Rosa rugosa, 3 promoters of transcription factors of Petunia hybrida, and 4 flanking sequences of T-DNA insertion sites in transgenic tobacco lines and 6 specific genes from sequenced genome of rice and Arabidopsis. Conclusions The successful amplification of target products through FPNI-PCR verified that this novel strategy is an effective, low cost and simple procedure. Furthermore, FPNI-PCR represents a more sensitive, rapid and accurate technique than the established TAIL-PCR and hiTAIL-PCR procedures. PMID:22093809

  1. Heme regulates the expression in Saccharomyces cerevisiae of chimaeric genes containing 5'-flanking soybean leghemoglobin sequences

    DEFF Research Database (Denmark)

    Jensen, E O; Marcker, K A; Villadsen, IS

    1986-01-01

    The TM1 yeast mutant was transformed with a 2 micron-derived plasmid (YEp24) which carries a chimaeric gene containing the Escherichia coli chloramphenicol acetyl transferase (CAT) gene fused to the 5'- and 3'-flanking regions of the soybean leghemoglobin (Lb) c3 gene. Expression of the chimaeric...

  2. Geologic Mapping of the Summit and Western Flank of Alba Mons, Mars

    Science.gov (United States)

    Crown, D. A.; Berman, D. C.; Platz, T.; Scheidt, S. P.; Hauber, E.; Weitz, C. M.

    2017-06-01

    This investigation employs imaging and topographic datasets to produce two 1:1M-scale geologic maps covering the Alba Mons summit (245-255°E, 32.5-47.5°N) and western flank (230-245°E, 37.5-47.5°N).

  3. Calculation of the sound transmission between dwellings by partitions and flanking structures

    NARCIS (Netherlands)

    Gerretsen, E.

    1979-01-01

    A calculation model is presented for the sound transmission between dwellings by partitions and by flanking structures, based on the application of classical theory. The most important data needed are the sound reduction index for direct transmission of the different structures and the vibration

  4. Magmatism on rift flanks : Insights from ambient noise phase velocity in Afar region

    NARCIS (Netherlands)

    Korostelev, F.; Weemstra, C.; Leroy, S.; Boschi, L.; Keir, D.; Ren, Y.; Molinari, I.; Ahmed, A.; Stuart, G.W.; Rolandone, F.; Khanbari, K.; Hammond, J.O.S.; Kendall, M.K.; Doubre, C.; Al Ganad, I.; Goitom, B.; Ayele, A.

    2015-01-01

    During the breakup of continents in magmatic settings, the extension of the rift valley is commonly assumed to initially occur by border faulting and progressively migrate in space and time toward the spreading axis. Magmatic processes near the rift flanks are commonly ignored. We present phase

  5. Interphase FISH detection of BCL2 rearrangement in follicular lymphoma using breakpoint-flanking probes

    NARCIS (Netherlands)

    Vaandrager, J W; Schuuring, E; Raap, T; Philippo, K; Kleiverda, K; Kluin, P

    Rearrangement of the BCL2 gene is an important parameter for the differential diagnosis of non-Hodgkin lymphomas. Although a relatively large proportion of breakpoints is clustered, many are missed by standard PCR. A FISH assay is therefore desired. Up to now, a lack of probes flanking the BCL2 gene

  6. An FTIR investigation of flanking sequence effects on the structure and flexibility of DNA binding sites.

    Science.gov (United States)

    Kahn, Talia R; Fong, Kimberly K; Jordan, Brian; Lek, Janista C; Levitan, Rachel; Mitchell, Patrick S; Wood, Corrina; Hatcher, Mary E

    2009-02-17

    Fourier transform infrared (FTIR) spectroscopy and a library of FTIR marker bands have been used to examine the structure and relative flexibilities conferred by different flanking sequences on the EcoRI binding site. This approach allowed us to examine unique peaks and subtle changes in the spectra of d(AAAGAATTCTTT)(2), d(TTCGAATTCGAA)(2), and d(CGCGAATTCGCG)(2) and thereby identify local changes in base pairing, base stacking, backbone conformation, glycosidic bond rotation, and sugar puckering in the studied sequences. The changes in flanking sequences induce differences in the sugar puckers, glycosidic bond rotation, and backbone conformations. Varying levels of local flexibility are observed within the sequences in agreement with previous biological activity assays. The results also provide supporting evidence for the presence of a splay in the G(4)-C(9) base pair of the EcoRI binding site and a potential pocket of flexibility at the G(4) cleavage site that have been proposed in the literature. In sum, we have demonstrated that FTIR is a powerful methodology for studying the effect of flanking sequences on DNA structure and flexibility, for it can provide information about the local structure of the nucleic acid and the overall relative flexibilities conferred by different flanking sequences.

  7. Effect of Cutting Fluids on the Flank Wear of High Speed and ...

    African Journals Online (AJOL)

    The effect of some cutting fluids namely: Mentholated spirit, paraffin, and soluble oil on the flank wear of High-speed steel and carbide tipped tools by orthogonal cutting has been studied. Cente lathe was used for cylindrical turning operated at a speed of 370rpm and depth of cut of 1mm to machine aluminum, brass, mild ...

  8. Comparison of flank and midline approaches to the ovariohysterectomy of cats.

    Science.gov (United States)

    Coe, R J; Grint, N J; Tivers, M S; Hotston Moore, A; Holt, P E

    2006-09-02

    In a survey of uk veterinary practitioners, 96 per cent indicated that they performed ovariohysterectomy on cats via flank laparatomy rather than a midline coeliotomy. At a veterinary teaching hospital 32 cats were spayed by the midline approach and 34 by the flank approach, by undergraduate students under the continuous supervision of a veterinary surgeon. The duration of each part of the procedures was recorded and information was obtained from the students, the supervisors and the owners of the cats by means of questionnaires. The total duration of the surgery and the students' assessment of the difficulty of the surgery were not significantly different between the two groups. The time taken from the skin incision to entering the peritoneum was significantly longer with the flank approach, but finding the uterus took significantly longer with the midline approach. There was a high incidence of wound complications, in the form of swelling, redness or discharges, but the only statistically significant difference between the groups was a greater incidence of discharges in the cats spayed via the flank (five cases) than in the cats spayed via the midline (one case).

  9. Cloning and analysis of the 5' and 3' flanking regions of the Crinum ...

    African Journals Online (AJOL)

    ... nested gene-specific primer and the nested adaptor primer. Finally, the amplified products are fractionated, cloned, and sequenced. Using this method, we cloned the 5' and 3' flanking region of a mannose-binding lectin gene based upon DNA fragment obtained from China Crinum (Crinum asiaticum var. (Roxb. ex Herb.) ...

  10. A New Mathematical Model for Flank Wear Prediction Using Functional Data Analysis Methodology

    Directory of Open Access Journals (Sweden)

    Sonja Jozić

    2014-01-01

    Full Text Available This paper presents a new approach improving the reliability of flank wear prediction during the end milling process. In the present work, prediction of flank wear has been achieved by using cutting parameters and force signals as the sensitive carriers of information about the machining process. A series of experiments were conducted to establish the relationship between flank wear and cutting force components as well as the cutting parameters such as cutting speed, feed per tooth, and radial depth of cut. In order to be able to predict flank wear a new linear regression mathematical model has been developed by utilizing functional data analysis methodology. Regression coefficients of the model are in the form of time dependent functions that have been determined through the use of functional data analysis methodology. The mathematical model has been developed by means of applied cutting parameters and measured cutting forces components during the end milling of workpiece made of 42CrMo4 steel. The efficiency and flexibility of the developed model have been verified by comparing it with the separate experimental data set.

  11. Association of the polymorphism in the 5' flanking region of the ovine ...

    African Journals Online (AJOL)

    The insulin-like growth factor 1 (IGF-I) gene has been described in several studies as a candidate gene for growth traits in farm animals. The present preliminary study attempts to establish associations between growth traits and genetic polymorphisms at the 5' flanking region s IGF-I in the Baluchi sheep. The DNA of 102 ...

  12. Molecular detection of infection homogeneity and impact of miltefosine treatment in a Syrian golden hamster model of Leishmania donovani and L. infantum visceral leishmaniasis.

    Science.gov (United States)

    Eberhardt, Eline; Mondelaers, Annelies; Hendrickx, Sarah; Van den Kerkhof, Magali; Maes, Louis; Caljon, Guy

    2016-10-01

    Control of visceral leishmaniasis caused by Leishmania infantum and Leishmania donovani primarily relies on chemotherapy using an increasingly compromised repertoire of antileishmanial compounds. For evaluation of novel drugs, the Syrian golden hamster is considered as a clinically relevant laboratory model. In this study, two molecular parasite detection assays were developed targeting cathepsin-like cysteine protease B (CPB) DNA and 18S rRNA to achieve absolute amastigote quantification in the major target organs liver and spleen. Both quantitative PCR (qPCR) techniques showed excellent agreement with a strong correlation with the conventional microscopic reading of Giemsa-stained tissue smears. Using multiple single tissue pieces and all three detection methods, we confirmed homogeneity of infection in liver and spleen and the robustness of extrapolating whole organ burdens from a small single tissue piece. Comparison of pre- and post-treatment burdens in infected hamsters using the three detection methods consistently revealed a stronger parasite reduction in the spleen compared to the liver, indicating an organ-dependent clearance efficacy for miltefosine. In conclusion, this study in the hamster demonstrated high homogeneity of infection in liver and spleen and advocates the use of molecular detection methods for assessment of low (post-treatment) tissue burdens.

  13. 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...

  14. Genetic spatial structure of European common hamsters (Cricetus cricetus) - a result of repeated range expansion and demographic bottlenecks

    NARCIS (Netherlands)

    Neumann, K.; Michaux, R.; Maak, S.; Jansman, H.A.H.; Kayser, A.; Mundt, G.; Gattermann, R.

    2005-01-01

    The spatial genetic structure of common hamsters (Cricetus cricetus) was investigated using three partial mitochondrial (mt) genes and 11 nuclear microsatellite loci. All marker systems revealed significant population differentiation across Europe. Hamsters in central and western Europe belong

  15. 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)...

  16. Sequencing, annotation and analysis of the Syrian hamster (Mesocricetus auratus) transcriptome.

    Science.gov (United States)

    Tchitchek, Nicolas; Safronetz, David; Rasmussen, Angela L; Martens, Craig; Virtaneva, Kimmo; Porcella, Stephen F; Feldmann, Heinz; Ebihara, Hideki; Katze, Michael G

    2014-01-01

    The Syrian hamster (golden hamster, Mesocricetus auratus) is gaining importance as a new experimental animal model for multiple pathogens, including emerging zoonotic diseases such as Ebola. Nevertheless there are currently no publicly available transcriptome reference sequences or genome for this species. A cDNA library derived from mRNA and snRNA isolated and pooled from the brains, lungs, spleens, kidneys, livers, and hearts of three adult female Syrian hamsters was sequenced. Sequence reads were assembled into 62,482 contigs and 111,796 reads remained unassembled (singletons). This combined contig/singleton dataset, designated as the Syrian hamster transcriptome, represents a total of 60,117,204 nucleotides. Our Mesocricetus auratus Syrian hamster transcriptome mapped to 11,648 mouse transcripts representing 9,562 distinct genes, and mapped to a similar number of transcripts and genes in the rat. We identified 214 quasi-complete transcripts based on mouse annotations. Canonical pathways involved in a broad spectrum of fundamental biological processes were significantly represented in the library. The Syrian hamster transcriptome was aligned to the current release of the Chinese hamster ovary (CHO) cell transcriptome and genome to improve the genomic annotation of this species. Finally, our Syrian hamster transcriptome was aligned against 14 other rodents, primate and laurasiatheria species to gain insights about the genetic relatedness and placement of this species. This Syrian hamster transcriptome dataset significantly improves our knowledge of the Syrian hamster's transcriptome, especially towards its future use in infectious disease research. Moreover, this library is an important resource for the wider scientific community to help improve genome annotation of the Syrian hamster and other closely related species. Furthermore, these data provide the basis for development of expression microarrays that can be used in functional genomics studies.

  17. 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

  18. A Comparison of Hamster Anesthetics and Their Effect on Mosquito Blood Feeding

    Science.gov (United States)

    Hamsters or mice are often anesthetized when they are used as the hosts for insect feeding experiments. An experiment was done to determine if there was a difference in mosquito blood feeding success when fed on hamsters anesthetized using two commonly used protocols. The number of blood-fed females...

  19. Syrian Hamsters as a Small Animal Model for Emerging Infectious Diseases: Advances in Immunologic Methods.

    Science.gov (United States)

    Warner, Bryce M; Safronetz, David; Kobinger, Gary P

    2017-01-01

    The use of small animal models for the study of infectious disease is critical for understanding disease progression and for developing prophylactic and therapeutic treatment options. For many diseases, Syrian golden hamsters have emerged as an ideal animal model due to their low cost, small size, ease of handling, and ability to accurately reflect disease progression in humans. Despite the increasing use and popularity of hamsters, there remains a lack of available reagents for studying hamster immune responses. Without suitable reagents for assessing immune responses, researchers are left to examine clinical signs and disease pathology. This becomes an issue for the development of vaccine and treatment options where characterizing the type of immune response generated is critical for understanding protection from disease. Despite the relative lack of reagents for use in hamsters, significant advances have been made recently with several hamster specific immunologic methods being developed. Here we discuss the progress of this development, with focus on classical methods used as well as more recent molecular methods. We outline what methods are currently available for use in hamsters and what is readily used as well as what limitations still exist and future perspectives of reagent and assay development for hamsters. This will provide valuable information to researchers who are deciding whether to use hamsters as an animal model.

  20. Diet affects resting, but not basal metabolic rate of normothermic Siberian hamsters acclimated to winter.

    Science.gov (United States)

    Gutowski, Jakub P; Wojciechowski, Michał S; Jefimow, Małgorzata

    2011-12-01

    We examined the effect of different dietary supplements on seasonal changes in body mass (m(b)), metabolic rate (MR) and nonshivering thermogenesis (NST) capacity in normothermic Siberian hamsters housed under semi-natural conditions. Once a week standard hamster food was supplemented with either sunflower and flax seeds, rich in polyunsaturated fatty acids (FA), or mealworms, rich in saturated and monounsaturated FA. We found that neither of these dietary supplements affected the hamsters' normal winter decrease in m(b) and fat content nor their basal MR or NST capacity. NST capacity of summer-acclimated hamsters was lower than that of winter-acclimated ones. The composition of total body fat reflected the fat composition of the dietary supplements. Resting MR below the lower critical temperature of the hamsters, and their total serum cholesterol concentration were lower in hamsters fed a diet supplemented with mealworms than in hamsters fed a diet supplemented with seeds. These results indicate that in mealworm-fed hamsters energy expenditure in the cold is lower than in animals eating a seed-supplemented diet, and that the degree of FA unsaturation of diet affects energetics of heterotherms, not only during torpor, but also during normothermy. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Functional evidence for alternative ANG II-forming pathways in hamster cardiovascular system

    NARCIS (Netherlands)

    Nishimura, H; Buikema, H; Baltatu, O; Ganten, D; Urata, H

    1998-01-01

    Like human chymase, hamster chymase is an ANG II-forming enzyme, but pathophysiological roles of chymase are still unknown. We determined the functional conversion of ANG I and [Pro(11), D-Ala(12)]ANG I, a chymase-selective substrate, to ANG II in the hamster cardiovascular system. ANG I and

  2. The last glacial termination on the eastern flank of the central Patagonian Andes (47 ° S)

    Science.gov (United States)

    Henríquez, William I.; Villa-Martínez, Rodrigo; Vilanova, Isabel; De Pol-Holz, Ricardo; Moreno, Patricio I.

    2017-07-01

    Few studies have examined in detail the sequence of events during the last glacial termination (T1) in the core sector of the Patagonian Ice Sheet (PIS), the largest ice mass in the Southern Hemisphere outside of Antarctica. Here we report results from Lago Edita (47°8' S, 72°25' W, 570 m a.s.l.), a small closed-basin lake located in a valley overridden by eastward-flowing Andean glaciers during the Last Glacial Maximum (LGM). The Lago Edita record shows glaciolacustrine sedimentation until 19 400 yr BP, followed by organic sedimentation in a closed-basin lake and a mosaic of cold-resistant hygrophilous conifers and rainforest trees, along with alpine herbs between 19 400 and 11 000 yr BP. Our data suggest that the PIS retreated at least ˜ 90 km from its LGM limit between ˜ 21 000 and 19 400 yr BP and that scattered, low-density populations of cold-resistant hygrophilous conifers, rainforest trees, high-Andean and steppe herbs thrived east of the Andes during the LGM and T1, implying high precipitation levels and southern westerly wind (SWW) influence at 47° S. The conifer Podocarpus nubigena increased between 14 500 and 13 000 yr BP, suggesting even stronger SWW influence during the Antarctic Cold Reversal, after which it declined and persisted until 11 000 yr BP. Large increases in arboreal pollen at ˜ 13 000 and ˜ 11 000 yr BP led to the establishment of forests near Lago Edita between 10 000 and 9000 yr BP, suggesting a rise in the regional tree line along the eastern Andean slopes driven by warming pulses at ˜ 13 000 and ˜ 11 000 yr BP and a subsequent decline in SWW influence at ˜ 11 000 yr BP. We propose that the PIS imposed a regional cooling signal along its eastern, downwind margin through T1 that lasted until the separation of the northern and southern Patagonian ice fields along the Andes during the Younger Dryas period. We posit that the withdrawal of glacial and associated glaciolacustrine environments through T1 provided a route for the

  3. Spontaneous nonneoplastic lesions in control Syrian hamsters in three 24-month long-term carcinogenicity studies.

    Science.gov (United States)

    McInnes, Elizabeth F; Ernst, Heinrich; Germann, Paul-Georg

    2015-02-01

    Information about the incidence of spontaneously occurring, nonneoplastic background findings in Syrian hamsters is essential if Syrian hamsters are to be used for toxicity studies. Male and female Syrian hamsters of the strain Han:AURA from the Fraunhofer Institute for Toxicology and Experimental Medicine (ITEM) breeding colony were maintained as control animals for carcinogenicity studies and were examined for the presence of nonneoplastic background findings either when they died or when the study was terminated. The nonneoplastic background lesions observed at an incidence of >50% (high), >25% (moderate), and >10% (low) in either male or female animals or in both sexes in one or more long-term studies are detailed. The results are compared to previous published reports of nonneoplastic, spontaneous background lesions in Syrian hamsters. Background information about the incidence of background lesions in Syrian hamsters on short- and long-term studies is useful to both toxicologists and toxicological pathologists. © 2014 by The Author(s).

  4. Three-dimensional displacements of a large volcano flank movement during the May 2010 eruptions at Pacaya Volcano, Guatemala

    Science.gov (United States)

    Schaefer, L. N.; Wang, T.; Escobar-Wolf, R.; Oommen, T.; Lu, Z.; Kim, J.; Lundgren, P. R.; Waite, G. P.

    2017-01-01

    Although massive flank failure is fairly common in the evolution of volcanoes, measurements of flank movement indicative of instability are rare. Here 3-D displacements from airborne radar amplitude images derived using an amplitude image pixel offset tracking technique show that the west and southwest flanks of Pacaya Volcano in Guatemala experienced large ( 4 m), discrete landsliding that was ultimately aborted. Pixel offset tracking improved measurement recovery by nearly 50% over classic interferometric synthetic aperture radar techniques, providing unique measurements at the event. The 3-D displacement field shows that the flank moved coherently downslope along a complex failure surface involving both rotational and along-slope movement. Notably, the lack of continuous movement of the slide in the years leading up to the event emphasizes that active movement should not always be expected at volcanoes for which triggering factors (e.g., magmatic intrusions and eruptions) could precipitate sudden major flank instability.

  5. A New Model of Progressive Visceral Leishmaniasis in Hamsters by Natural Transmission via Bites of Vector Sand Flies

    Science.gov (United States)

    Aslan, Hamide; Dey, Ranadhir; Meneses, Claudio; Castrovinci, Philip; Jeronimo, Selma Maria Bezerra; Oliva, Gætano; Fischer, Laurent; Duncan, Robert C.; Nakhasi, Hira L.; Valenzuela, Jesus G.; Kamhawi, Shaden

    2013-01-01

    Background. Visceral leishmaniasis (VL) is transmitted by sand flies. Protection of needle-challenged vaccinated mice was abrogated in vector-initiated cutaneous leishmaniasis, highlighting the importance of developing natural transmission models for VL. Methods. We used Lutzomyia longipalpis to transmit Leishmania infantum or Leishmania donovani to hamsters. Vector-initiated infections were monitored and compared with intracardiac infections. Body weights were recorded weekly. Organ parasite loads and parasite pick-up by flies were assessed in sick hamsters. Results. Vector-transmitted L. infantum and L. donovani caused ≥5-fold increase in spleen weight compared with uninfected organs and had geometric mean parasite loads (GMPL) comparable to intracardiac inoculation of 107–108 parasites, although vector-initiated disease progression was slower and weight loss was greater. Only vector-initiated L. infantum infections caused cutaneous lesions at transmission and distal sites. Importantly, 45.6%, 50.0%, and 33.3% of sand flies feeding on ear, mouth, and testicular lesions, respectively, were parasite-positive. Successful transmission was associated with a high mean percent of metacyclics (66%–82%) rather than total GMPL (2.0 × 104–8.0 × 104) per midgut. Conclusions. This model provides an improved platform to study initial immune events at the bite site, parasite tropism, and pathogenesis and to test drugs and vaccines against naturally acquired VL. PMID:23288926

  6. A new model of progressive visceral leishmaniasis in hamsters by natural transmission via bites of vector sand flies.

    Science.gov (United States)

    Aslan, Hamide; Dey, Ranadhir; Meneses, Claudio; Castrovinci, Philip; Jeronimo, Selma Maria Bezerra; Oliva, Gætano; Fischer, Laurent; Duncan, Robert C; Nakhasi, Hira L; Valenzuela, Jesus G; Kamhawi, Shaden

    2013-04-15

    Visceral leishmaniasis (VL) is transmitted by sand flies. Protection of needle-challenged vaccinated mice was abrogated in vector-initiated cutaneous leishmaniasis, highlighting the importance of developing natural transmission models for VL. We used Lutzomyia longipalpis to transmit Leishmania infantum or Leishmania donovani to hamsters. Vector-initiated infections were monitored and compared with intracardiac infections. Body weights were recorded weekly. Organ parasite loads and parasite pick-up by flies were assessed in sick hamsters. Vector-transmitted L. infantum and L. donovani caused ≥5-fold increase in spleen weight compared with uninfected organs and had geometric mean parasite loads (GMPL) comparable to intracardiac inoculation of 10(7)-10(8) parasites, although vector-initiated disease progression was slower and weight loss was greater. Only vector-initiated L. infantum infections caused cutaneous lesions at transmission and distal sites. Importantly, 45.6%, 50.0%, and 33.3% of sand flies feeding on ear, mouth, and testicular lesions, respectively, were parasite-positive. Successful transmission was associated with a high mean percent of metacyclics (66%-82%) rather than total GMPL (2.0 × 10(4)-8.0 × 10(4)) per midgut. This model provides an improved platform to study initial immune events at the bite site, parasite tropism, and pathogenesis and to test drugs and vaccines against naturally acquired VL.

  7. [Genotyping and evaluation of infection dynamics in a Colombian isolate of Leptospira santarosai in hamster as an experimental model].

    Science.gov (United States)

    Agudelo-Flórez, Piedad; Durango, Harold; Aranzazu, Diego; Rodas, Juan David; Travi, Bruno

    2014-01-01

    Is necessary to develop models for the study of leptospirosis. To genotype a Colombian strain of Leptospira isolated from a human with Weil´s syndrome and to evaluate its infection dynamics in the hamster experimental model. Genotyping was performed by amplification and sequence analysis of the rrs 16S and lipL32 genes. The median lethal dose was determined in intraperitoneally inoculated hamsters. The patterns of clinical chemistry, the duration of leptospiremia, leptospiruria and pathological findings were studied and compared in the same animal model infected with L. interrogans (Fiocruz L1-130). Molecular typing revealed that the isolate corresponded to the pathogenic species L. santarosai, which was recovered from hamsters´ kidneys and lungs and detected by lipL32 PCR from day 3 post-infection in these organs. There was a marked increase of C-reactive protein in animals at day 5 post-infection (3.25 mg/dl; normal value: 0.3 mg/dl) with decreases by day 18 (2.60 mg/dl: normal value: 0.8 mg/dl). Biomarkers of urea showed changes consistent with possible renal acute failure (day 5 post-infection: 49.01 mg/dl and day 18 post-infection: 53.71 mg/dl). Histopathological changes included interstitial pneumonia with varying degrees of hemorrhage and interstitial nephritis. The pathogenic species L. santarosai was identified in Colombia. Its pathogenicity as determined by tropism to lung and kidney was comparable to that of L. interrogans Fiocruz L1-130, well known for its virulence and pulmonar tropism. The biological aspects studied here had never before been evaluated in an autochthonous isolate.

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

    OpenAIRE

    Eduardo Monge; Paulo M Z Coelho; Tavares, Carlos A. P.

    1986-01-01

    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 e...

  9. Organizers.

    Science.gov (United States)

    Callison, Daniel

    2000-01-01

    Focuses on "organizers," tools or techniques that provide identification and classification along with possible relationships or connections among ideas, concepts, and issues. Discusses David Ausubel's research and ideas concerning advance organizers; the implications of Ausubel's theory to curriculum and teaching; "webbing," a…

  10. Inoculation of Lacazia loboi into the subcutaneous tissue of the hamster cheek pouch Inoculação de Lacazia loboi no tecido celular subcutâneo da bolsa jugal do hamster

    Directory of Open Access Journals (Sweden)

    Diltor Vladimir Araujo OPROMOLLA

    2000-06-01

    Full Text Available The subcutaneous tissue of the hamster cheek pouch, a site of immunologic privilege, has been used to investigate the potential infectivity of different types of parasites. It has been demonstrated that the implantation of fragments of lesions induced by the fungus Lacazia loboi, the etiologic agent of Jorge Lobo's disease, into the subcutaneous tissue of the hamster cheek pouch resulted in parasite multiplication and dissemination to satellite lymph nodes16. Here we describe the evolution of lesions induced by the inoculation of the isolated fungus into this immunologically privileged site. The morphology of the inflammatory response and fungal viability and proliferation were evaluated. Inoculation of the fungus into the cheek pouch induced histiocytic granulomas with rare lymphocytes. Although fungal cells were detected for a period of up to 180 days in these lesions, the fungi lost viability after the first day of inoculation. In contrast, when the parasite was inoculated into the footpad, non-organized histiocytic lesions were observed. Langhan's giant cells, lymphocytes and fungal particles were observed in these lesions. Fungal viability was observed up to 60 days after inoculation and non-viable parasites were present in the persistent lesions up to 180 days post-inoculation. These data indicate that the subcutaneous tissue of the hamster cheek pouch is not a suitable site for the proliferation of Lacazia loboi when the fungus isolated from human tissues is tested.O tecido celular subcutâneo da bolsa jugal do hamster, um local de privilégio imunológico, tem sido usado para a investigação da infectividade potencial de diferentes tipos de parasitas. Está demonstrado que o implante de fragmentos de lesões induzidas pelo fungo Lacazia loboi, o agente etiológico da doença de Jorge Lobo, no tecido subcutâneo da bolsa jugal do hamster resultou na multiplicação e disseminação do parasita para linfonodos satélites16. Neste trabalho

  11. Stability analysis of Western flank of Cumbre Vieja volcano (La Palma) using numerical modelling

    Science.gov (United States)

    Bru, Guadalupe; Gonzalez, Pablo J.; Fernandez-Merodo, Jose A.; Fernandez, Jose

    2016-04-01

    La Palma volcanic island is one of the youngest of the Canary archipelago, being a composite volcano formed by three overlapping volcanic centers. There are clear onshore and offshore evidences of past giant landslides that have occurred during its evolution. Currently, the active Cumbre Vieja volcano is in an early development state (Carracedo et al., 2001). The study of flank instability processes aim to assess, among other hazards, catastrophic collapse and potential tsunami generation. Early studies of the potential instability of Cumbre Vieja volcano western flank have focused on the use of sparse geodetic networks (Moss et al. 1999), surface geological mapping techniques (Day et al. 1999) and offshore bathymetry (Urgeles et al. 1999). Recently, a dense GNSS network and satellite radar interferometry results indicate ground motion consistent with deep-seated creeping processes (Prieto et al. 2009, Gonzalez et al. 2010). In this work, we present a geomechanical advanced numerical model that captures the ongoing deformation processes at Cumbre Vieja. We choose the Finite Elements Method (FEM) which is based in continuum mechanics and is the most used for geotechnical applications. FEM has the ability of using arbitrary geometry, heterogeneities, irregular boundaries and different constitutive models representative of the geotechnical units involved. Our main contribution is the introduction of an inverse approach to constrain the geomechanical parameters using satellite radar interferometry displacements. This is the first application of such approach on a large volcano flank study. We suggest that the use of surface displacements and inverse methods to rigorously constrain the geomechanical model parameter space is a powerful tool to understand volcano flank instability. A particular important result of the studied case is the estimation of displaced rock volume, which is a parameter of critical importance for simulations of Cumbre Vieja tsunamigenic hazard

  12. Exploring the links between volcano flank collapse and magma evolution: Fogo oceanic shield volcano, Cape Verde

    Science.gov (United States)

    Cornu, Melodie-Neige; Paris, Raphael; Doucelance, Regis; Bachelery, Patrick; Guillou, Hervé

    2017-04-01

    Mass wasting of oceanic shield volcanoes is largely documented through the recognition of collapse scars and submarine debris fans. However, it is actually difficult to infer the mechanisms controlling volcano flank failures that potentially imply tens to hundreds of km3. Studies coupling detailed petrological and geochemical analyses of eruptive products hold clues for better understanding the relationships between magma sources, the plumbing system, and flank instability. Our study aims at tracking potential variations of magma source, storage and transport beneath Fogo shield volcano (Cape Verde) before and after its major flank collapse. We also provide a geochronological framework of this magmatic evolution through new radiometric ages (K-Ar and Ar-Ar) of both pre-collapse and post-collapse lavas. The central part of Fogo volcanic edifice is truncated by an 8 km-wide caldera opened to the East, corresponding to the scar of the last flank collapse (Monte Amarelo collapse, Late Pleistocene, 150 km3). Lavas sampled at the base of the scar (the so-called Bordeira) yielded ages between 158 and 136 ka. The age of the collapse is constrained between 68 ka (youngest lava flow cut by the collapse scar) and 59 ka (oldest lava flow overlapping the scar). The collapse walls display a complex structural, intrusive and eruptive history. Undersaturated volcanism (SiO2elements analyses indicate that the pre-collapse lavas are significantly less differentiated than post-collapse lavas, with a peak of alkalis at the collapse. Rare-earth elements concentration decreases with time, with a notable positive anomaly before the collapse. The evolution of the isotopic ratios (Sr, Nd and Pb) through time displays unusual V-shaped profiles centered around the collapse. The occurrence of the Monte Amarelo collapse is thus not disconnected from the magmatic evolution, both at the crustal and mantellic levels. Our results also point out the importance and relative frequency of explosive

  13. Evidence of sheared sills related to flank destabilization in a basaltic volcano

    Science.gov (United States)

    Berthod, C.; Famin, V.; Bascou, J.; Michon, L.; Ildefonse, B.; Monié, P.

    2016-04-01

    Piton des Neiges basaltic volcano (La Réunion) has been deeply dissected by erosion, exposing large volumes of debris avalanche deposits. To shed light on the factors that led to volcano flank destabilizations, we studied the structure, the crystallographic and magnetic fabrics of the substratum of a debris avalanche unit. This substratum is a complex of > 50 seaward-dipping sills that has been exposed by the avalanche. Structural observations show that the sill plane in contact with the avalanche is one of the latest intrusions in the sill complex. In this uppermost sill, the anisotropy of magnetic susceptibility (AMS) is correlated to the crystallographic preferred orientation of magmatic silicate minerals, allowing us to use AMS as a proxy to infer the magmatic flow. The AMS fabric across the intrusion is strongly asymmetric, which reveals that the contact sill was emplaced with a normal shear displacement of its hanging wall. The shear displacement and the magma flow in the intrusion are both directed toward the NNE, i.e. toward the sea, which is also the direction of the slope and of the debris avalanche runout. Because all the sills in the intrusion complex have a similar dip and dip direction, it is likely that several of them also underwent a cointrusive slip toward the NNE. We conclude that this cointrusive normal slip, repeated over many intrusions of the sill complex, increased the flank instability of the volcano. This incremental instability may have ended up into the observed debris avalanche deposit. At Piton de la Fournaise, the active volcano of La Réunion, sill intrusion and cointrusive flank displacement have been inferred from geophysical studies for the April 2007 eruption. By providing direct evidence of sheared sills, our study substantiates the idea that repeated sill intrusions may eventually trigger flank destabilizations in basaltic volcanoes.

  14. Method for Friction Force Estimation on the Flank of Cutting Tools

    Directory of Open Access Journals (Sweden)

    Luis Huerta

    2017-01-01

    Full Text Available Friction forces are present in any machining process. These forces could play an important role in the dynamics of the system. In the cutting process, friction is mainly present in the rake face and the flank of the tool. Although the one that acts on the rake face has a major influence, the other one can become also important and could take part in the stability of the system. In this work, experimental identification of the friction on the flank is presented. The experimental determination was carried out by machining aluminum samples in a CNC lathe. As a result, two friction functions were obtained as a function of the cutting speed and the relative motion of the contact elements. Experiments using a worn and a new insert were carried out. Force and acceleration were recorded simultaneously and, from these results, different friction levels were observed depending on the cutting parameters, such as cutting speed, feed rate, and tool condition. Finally, a friction model for the flank friction is presented.

  15. Pancreatic Tail Cancer with Sole Manifestation of Left Flank Pain: A Very Rare Presentation

    Directory of Open Access Journals (Sweden)

    Hsing-Lin Lin

    2008-06-01

    Full Text Available Pancreatic cancer is sometimes called a “silent disease” because it often causes no symptoms in the early stage. The symptoms can be quite vague and various depending on the location of cancer in the pancreas. The anatomic site distribution is 78% in the head of the pancreas, 11% in the body, and 11% in the tail. Pancreatic cancer is rarely detected in the early stage, and it is very uncommon to diagnose pancreatic tail cancer during an emergency department visit. The manifestation of pancreatic tail cancer as left flank pain is very rare and has seldom been identified in the literature. We present a case of pancreatic tail cancer with the sole manifestation of dull left flank pain. Having negative findings on an ultrasound study initially, this female patient was misdiagnosed as having possible acute gastritis, urolithiasis or muscle strain after she received gastroendoscopy and colonofiberscopy. Her symptoms persisted for several months and she visited our emergency department due to an acute exacerbation of a persistent dull pain in the left flank area. Radiographic evaluation with computed tomography was performed, and pancreatic tail tumor with multiple metastases was found unexpectedly. We review the literature and discuss this rare presentation of pancreatic tail cancer.

  16. 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

    Directory of Open Access Journals (Sweden)

    Dimas José Araújo Vidigal

    2004-12-01

    monoblock extracting of the genitourinary system for a histologic study of sexual anexes and found changes to dosed PSA. Among young Hamsters the PSA found level was 0,252ng/mL, Pattern change (PC = 0,36. Among adult Hamsters, the average was 0,325ng/mL, (PC=0,12. When comparing these PSA averages between the young and adult groups, the obtained result was p= 0.0427. Among young Hamsters, three of them presented PSA no detectable and young animals did not present histologic changes in their checked sexual annexes, among adult Hamsters, fourteen (70 of them presented change in their sexual annexes such as: ten (50% present only PBH (Prostate Benign Hiperplasia, one (5% prostatitis and seminal vesicle inflammation and PBH, one (5% seminal vesicle suppurative inflammation, one (5% seminal vesicle inflammation and one (5% presented testicle infarct and prostatitis. Conclusion: The depicted surgical technique has shown to be efficient in obtaining the genitourinary system with its organs and structures, even for a histologic study of those organs and PSA dosing in Syrian Hamster, Mesocricetus auratus.

  17. Effects of Spirulina platensis extract on Syrian hamster cheek pouch mucosa painted with 7,12-dimethylbenz[a]anthracene.

    Science.gov (United States)

    Grawish, Mohammed E

    2008-10-01

    Research into cancer prevention seeks to identify the preventable causes of cancer, and to reduce cancer incidence by effective implementation of preventative strategies in target populations. In this study, 30 male golden Syrian hamsters were divided into three equal groups; the right buccal pouches of the hamster rats in group one were painted with 0.5% solution of 7,12-dimethylbenz[a]anthracene (DMBA), three times a week, until sacrificed. The same pouches of group two were also painted with DMBA, but received an additional 10mg/daily Spirulina platensis extract, which was added to the soft diet supplements during the same period. The hamster rats in group three received neither DMBA nor S. platensis extract. They were painted with saline and served as control animals. Half the hamsters from each of the three groups were sacrificed by ether inhalation after 7 weeks, and the remaining half were sacrificed after 14 weeks. The required buccal pouches were surgically excised and prepared for regular H&E and argyrophilic proteins of the nuclear organizer regions (AgNOR) silver staining. AgNORs counting and statistical analysis were carried out. We observed moderate dysplastic changes extending into the midspinous layer in group one 7 weeks after DMBA painting, which reached to half the thickness of the hyperplastic epithelium after 14 weeks. However, in group two, mild dysplastic changes were observed after 7 weeks, which were restricted to the basilar and parabasilar layers of the epithelium after 14 weeks of treatment. AgNOR staining in group one produced AgNOR counts ranging from one to seven dots per nucleus, whereas the counts were one or two dots per nucleus in group two. The AgNOR mean number in groups one, two and three was (3.1+/-0.006, 1.3+/-0.003 and 1.2+/-0.003, respectively). Moreover, with one sample t-test, a significant difference was found in AgNOR mean number between groups one and two, groups one and three and between groups two and three (Phamster

  18. Organizations

    DEFF Research Database (Denmark)

    Hatch, Mary Jo

    Most of us recognize that organizations are everywhere. You meet them on every street corner in the form of families and shops, study in them, work for them, buy from them, pay taxes to them. But have you given much thought to where they came from, what they are today, and what they might become...... and considers many more. Mary Jo Hatch introduces the concept of organizations by presenting definitions and ideas drawn from the a variety of subject areas including the physical sciences, economics, sociology, psychology, anthropology, literature, and the visual and performing arts. Drawing on examples from...... prehistory and everyday life, from the animal kingdom as well as from business, government, and other formal organizations, Hatch provides a lively and thought provoking introduction to the process of organization....

  19. Social forces can impact the circadian clocks of cohabiting hamsters

    Science.gov (United States)

    Paul, Matthew J.; Indic, Premananda; Schwartz, William J.

    2014-01-01

    A number of field and laboratory studies have shown that the social environment influences daily rhythms in numerous species. However, underlying mechanisms, including the circadian system's role, are not known. Obstacles to this research have been the inability to track and objectively analyse rhythms of individual animals housed together. Here, we employed temperature dataloggers to track individual body temperature rhythms of pairs of cohabiting male Syrian hamsters (Mesocricetus auratus) in constant darkness and applied a continuous wavelet transform to determine the phase of rhythm onset before, during, and after cohabitation. Cohabitation altered the predicted trajectory of rhythm onsets in 34% of individuals, representing 58% of pairs, compared to 12% of hamsters single-housed as ‘virtual pair’ controls. Deviation from the predicted trajectory was by a change in circadian period (τ), which tended to be asymmetric—affecting one individual of the pair in nine of 11 affected pairs—with hints that dominance might play a role. These data implicate a change in the speed of the circadian clock as one mechanism whereby social factors can alter daily rhythms. Miniature dataloggers coupled with wavelet analyses should provide powerful tools for future studies investigating the principles and mechanisms mediating social influences on daily timing. PMID:24500164

  20. Anti-hypercholesterolemic effect of Saccharomyces boulardii in the hamster.

    Science.gov (United States)

    Girard, Philippe; Pansart, Yannick; Verleye, Marc

    2014-01-01

    Hypercholesterolemia is a major risk factor for coronary artery disease and probiotics have been suggested as tools to manage elevated cholesterol levels. The present study investigated the ability of the biotherapeutic agent Saccharomyces boulardii (Sb-Biocodex) to reduce the hypercholesterolemia induced by a 0.1% cholesterol-enriched diet in the hamster. In a first experiment, chronic oral treatment with S. boulardii at 12 × 10(10) CFU/kg (3 g/kg) twice a day was started from the beginning of the cholesterol diet and continued for 14 days ('preventive protocol'). In the second experiment, S. boulardii was given 14 days after the beginning of the cholesterol diet when hypercholesterolemia had developed and continued for an additional 14 days ('curative protocol'). In the preventive protocol, administration of the yeast significantly reduced hypercholesterolemia (14%) induced by the cholesterol-enriched diet compared to the group receiving only the cholesterol diet. In the curative protocol, S. boulardii significantly reduced hypercholesterolemia (12%) induced by the cholesterol-enriched diet, too. Moreover, the yeast significantly decreased the serum triglyceride increase by 39%. S. boulardii possesses anti-hypercholesterolemic properties in the hamster worthy of further evaluation in clinical studies. © 2014 S. Karger AG, Basel.

  1. Serum lysophospholipid levels are altered in dyslipidemic hamsters.

    Science.gov (United States)

    Suárez-García, Susana; Caimari, Antoni; Del Bas, Josep Maria; Suárez, Manuel; Arola, Lluís

    2017-09-05

    Dyslipidemias are common disorders that predispose individuals to severe diseases. It is known that healthy living habits can prevent dyslipidemias if they are diagnosed properly. Therefore, biomarkers that assist in diagnosis are essential. The aim of this study was to identify biomarkers of dyslipidemia progression, which in turn disclose its etiology. These findings will pave the way for examinations of the regulatory mechanisms involved in dyslipidemias. Hamsters were fed either a normal-fat diet (NFD) or a high-fat diet. Some of the NFD-fed animals were further treated with the hyperlipidemic agent Poloxamer 407. Non-targeted metabolomics was used to investigate progressive changes in unknown serum metabolites. The hepatic expression of putative biomarker-related genes was also analyzed. The serum levels of lysophospholipids (Lyso-PLs) and their related enzymes lecithin-cholesterol acyltransferase (LCAT), secreted phospholipase A2 (sPLA2) and paraoxonase-1 were altered in dyslipidemic hamsters. Lysophosphatidylcholine levels were increased in diet-induced dyslipidemic groups, whereas lysophosphatidylethanolamine levels increased in response to the chemical treatment. The liver was significantly involved in regulating the levels of these molecules, based on the modified expression of endothelial lipase (Lipg), sPLA2 (Pla2g2a) and acyltransferases (Lcat and Lpcat3). We concluded that Lyso-PL evaluation could aid in the comprehensive diagnosis and management of lipid disorders.

  2. 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.

  3. 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.

  4. Experimental study of the interplay between magmatic rift intrusion and flank instability with application to the 2001 Mount Etna eruption

    KAUST Repository

    Le Corvec, Nicolas

    2014-07-01

    Mount Etna volcano is subject to transient magmatic intrusions and flank movement. The east flank of the edifice, in particular, is moving eastward and is dissected by the Timpe Fault System. The relationship of this eastward motion with intrusions and tectonic fault motion, however, remains poorly constrained. Here we explore this relationship by using analogue experiments that are designed to simulate magmatic rift intrusion, flank movement, and fault activity before, during, and after a magmatic intrusion episode. Using particle image velocimetry allows for a precise temporal and spatial analysis of the development and activity of fault systems. The results show that the occurrence of rift intrusion episodes has a direct effect on fault activity. In such a situation, fault activity may occur or may be hindered, depending on the interplay of fault displacement and flank acceleration in response to dike intrusion. Our results demonstrate that a complex interplay may exist between an active tectonic fault system and magmatically induced flank instability. Episodes of magmatic intrusion change the intensity pattern of horizontal flank displacements and may hinder or activate associated faults. We further compare our results with the GPS data of the Mount Etna 2001 eruption and intrusion. We find that syneruptive displacement rates at the Timpe Fault System have differed from the preeruptive or posteruptive periods, which shows a good agreement of both the experimental and the GPS data. Therefore, understanding the flank instability and flank stability at Mount Etna requires consideration of both tectonic and magmatic forcing. Key Points Analyzing Mount Etna east flank dynamics during the 2001 eruption Good correlation between analogue models and GPS data Understanding the different behavior of faulting before/during/after an eruption © 2014. American Geophysical Union. All Rights Reserved.

  5. A lethal disease model for New World hantaviruses using immunosuppressed Syrian hamsters.

    Science.gov (United States)

    Vergote, Valentijn; Laenen, Lies; Vanmechelen, Bert; Van Ranst, Marc; Verbeken, Erik; Hooper, Jay W; Maes, Piet

    2017-10-01

    Hantavirus, the hemorrhagic causative agent of two clinical diseases, is found worldwide with variation in severity, incidence and mortality. The most lethal hantaviruses are found on the American continent where the most prevalent viruses like Andes virus and Sin Nombre virus are known to cause hantavirus pulmonary syndrome. New World hantavirus infection of immunocompetent hamsters results in an asymptomatic infection except for Andes virus and Maporal virus; the only hantaviruses causing a lethal disease in immunocompetent Syrian hamsters mimicking hantavirus pulmonary syndrome in humans. Hamsters, immunosuppressed with dexamethasone and cyclophosphamide, were infected intramuscularly with different New World hantavirus strains (Bayou virus, Black Creek Canal virus, Caño Delgadito virus, Choclo virus, Laguna Negra virus, and Maporal virus). In the present study, we show that immunosuppression of hamsters followed by infection with a New World hantavirus results in an acute disease that precisely mimics both hantavirus disease in humans and Andes virus infection of hamsters. Infected hamsters showed specific clinical signs of disease and moreover, histological analysis of lung tissue showed signs of pulmonary edema and inflammation within alveolar septa. In this study, we were able to infect immunosuppressed hamsters with different New World hantaviruses reaching a lethal outcome with signs of disease mimicking human disease.

  6. Effect of naltrexone on food intake and body weight in Syrian hamsters depends on metabolic status.

    Science.gov (United States)

    Jones, Juli E; Corp, Eric S

    2003-01-01

    Opioids are a family of neuropeptides involved in the control of food intake and regulation of body weight. In general, nonselective opioid antagonists have inhibited food intake in a variety of paradigms in rodent species. Syrian hamsters may be an exception to the general findings. In a previous report, we showed that systemic administration of an opioid antagonist, naltrexone, for 2 days increased body weight in female Syrian hamsters. To confirm the extent of these finding we designed the present experiment testing the effect of a chronic 6-day infusion of naltrexone on food intake, water intake, and body weight in freely feeding male hamsters. In addition, we examined the effect of acute administration of naltrexone on food intake in both ad-libitum-fed and food-deprived hamsters. We found that chronic systemic administration of naltrexone caused a significant increase in food intake and body weight. Second, acute administration of naltrexone decreased food intake after a 48-h fast but had no effect in ad-libitum-fed hamsters. Water consumption was not altered in any experimental paradigm. Our results suggest that opioid circuits in Syrian hamsters may function tonically to suppress food intake and body weight when Syrian hamsters are in positive energy balance. Paradoxically, opioids may enhance food intake after a sustained fast.

  7. 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.

  8. Modification of the pathogenicity of Schistosoma mattheei for sheep by passage of the parasite in hamsters.

    Science.gov (United States)

    Taylor, M G; James, E R; Nelson, G S; Bickle, Q; Dunne, D W; Dobinson, A R; Dargie, J D; Berry, C I; Hussein, M F

    1977-01-01

    Border Leicester X Suffolk sheep infected with a strain of S. mattheei maintained in hamsters do not develop the same pathological changes as Romney Marsh sheep infected with the same strain of parasite before hamster passage. To determine the cause of this reduced pathogenicity, five Romney Marsh sheep were each infected with 10 000 cercariae of the hamster-passaged parasite and five with 10 000 cercariae of a S. mattheei strain from Onderstepoort, South Africa, passaged exclusively through sheep. Striking pathological and parasitological differences were found between the two strains. Infection with the "sheep" strain was lethal, whereas infection with the "hamster" strain produced little evidence of clinical disease. By 13 weeks post-infection the mean body weight of the sheep infected with the sheep strain had declined by 15% compared with both the uninfected controls and the sheep infected with the hamster strain, and the mean PCV was lowered to 20% in the sheep strain infected animals. Egg production began at seven weeks with the sheep strain, faecal counts rising to more than 300 e.p.g., whereas only two of the sheep infected with the hamster strain passed eggs in the faeces (at nine weeks) and the maximum egg count was 50 e.p.g. Twice as many adult worms of the sheep strain were recovered, and, although the number of eggs found in the tissues "per worm pair" was not significantly different, overall egg production was higher for the sheep strain; also more of the sheep strain eggs were deposited in the intestines. Similar parasite differences were seen in a supplementary study in mice and it seemed that "attenuation" of the parasite had occurred, presumably due to its maintenance in hamsters. Histopathological observations and faecal egg counts both indicated an inability of hamster strain eggs to penetrate the intestinal lumen; this was probably important in reducing the pathogenicity of the hamster strain.

  9. 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)

  10. Omega 3 Fatty Acids Promote Macrophage Reverse Cholesterol Transport in Hamster Fed High Fat Diet

    OpenAIRE

    Fatima Kasbi Chadli; Hassane Nazih; Michel Krempf; Patrick Nguyen; Khadija Ouguerram

    2013-01-01

    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 (3)H-cholesterol-labelled hamster primary macrop...

  11. Infestivity of Demodex canis to hamster skin engrafted onto SCID mice.

    Science.gov (United States)

    Tani, Kenji; Une, Satoshi; Hasegawa, Atsuhiko; Adachi, Makoto; Kanda, Naoko; Watanabe, Shin-ichi; Nakaichi, Munekazu; Taura, Yasuho

    2005-04-01

    We demonstrated that Demodex canis was transferred to skin xenografts of a dog and a hamster onto severe combined immunodeficiency mice. After the transfer of mites, the number of eggs, larvae, nymphs and adult mites per gram of canine and hamster xenografts increased, whereas no live mites were detected on murine allograft. These results indicate that D. canis proliferates in hair follicles of dog and hamster skins but not in murine allograft. Therefore, D. canis may have host preference but not strict host-specificity.

  12. 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.

  13. Short-day response in Djungarian hamsters of different circadian phenotypes.

    Science.gov (United States)

    Schöttner, Konrad; Schmidt, Maren; Hering, Anke; Schatz, Juliane; Weinert, Dietmar

    2012-05-01

    In Djungarian hamsters (Phodopus sungorus) bred at the authors' institute, a certain number of animals show activity patterns incompatible with proper entrainment of their endogenous circadian pacemaker to the environmental light-dark (LD) cycle. Even though the activity-offset in these animals is stably coupled to "light-on," activity-onset is increasingly delayed, leading to a compression of the activity time (α). If α falls below a critical value, the circadian rhythm in these so called delayed activity-onset (DAO) hamsters starts to free-run and finally breaks down. Animals then show an arrhythmic activity pattern (AR hamsters). Previous studies revealed the mechanisms of photic entrainment have deteriorated (DAO) or the suprachiasmatic nucleus (SCN) does not generate a rhythmic signal (AR). The aim of the present study was to investigate the consequences that these deteriorations have upon photoperiodic time measurement. Animals were bred and kept under standardized housing conditions with food and water ad libitum and a 14L/10D (long day, LD) regimen. Locomotor activity was recorded continuously using passive infrared motion detectors. Body mass, testes size, and fur coloration were measured weekly or biweekly to further quantify the photoperiodic reaction. In a first experiment, adult male wild-type (WT), DAO, and AR hamsters were transferred initially to a 16L/8D cycle. After 3-4 wks, the light period was shortened symmetrically by 8 h. After 14 wks, none of the DAO and AR hamsters, and only 1 of 8 WT hamsters showed short-day (SD) traits. Therefore, in a second experiment, hamsters were transferred to SD conditions (8L/16D cycle) for 8 wks directly from standard LD conditions. In 6 of 7 WT hamsters, activity time expanded, body mass and testes size decreased, and fur coloration changed from summer to winter pelage. In contrast, none of the DAO and AR hamsters displayed an SD response. In a third experiment, DAO and AR hamsters were kept in constant

  14. Turbulence and Heating in the Flank and Wake Regions of a Coronal Mass Ejection

    Science.gov (United States)

    Fan, Siteng; He, Jiansen; Yan, Limei; Tomczyk, Steven; Tian, Hui; Song, Hongqiang; Wang, Linghua; Zhang, Lei

    2018-01-01

    As a coronal mass ejection (CME) passes, the flank and wake regions are typically strongly disturbed. Various instruments, including the Large Angle and Spectroscopic Coronagraph (LASCO), the Atmospheric Imaging Assembly (AIA), and the Coronal Multi-channel Polarimeter (CoMP), observed a CME close to the east limb on 26 October 2013. A hot ({≈} 10 MK) rising blob was detected on the east limb, with an initial ejection flow speed of {≈} 330 km s^{-1}. The magnetic structures on both sides and in the wake of the CME were strongly distorted, showing initiation of turbulent motions with Doppler-shift oscillations enhanced from {≈} ± 3 km s^{-1} to {≈} ± 15 km s^{-1} and effective thermal velocities from {≈} 30 km s^{-1} to {≈} 60 km s^{-1}, according to the CoMP observations at the Fe xiii line. The CoMP Doppler-shift maps suggest that the turbulence behaved differently at various heights; it showed clear wave-like torsional oscillations at lower altitudes, which are interpreted as the antiphase oscillation of an alternating red/blue Doppler shift across the strands at the flank. The turbulence seems to appear differently in the channels of different temperatures. Its turnover time was {≈} 1000 seconds for the Fe 171 Å channel, while it was {≈} 500 seconds for the Fe 193 Å channel. Mainly horizontal swaying rotations were observed in the Fe 171 Å channel, while more vertical vortices were seen in the Fe 193 Å channel. The differential-emission-measure profiles in the flank and wake regions have two components that evolve differently: the cool component decreased over time, evidently indicating a drop-out of cool materials due to ejection, while the hot component increased dramatically, probably because of the heating process, which is suspected to be a result of magnetic reconnection and turbulence dissipation. These results suggest a new turbulence-heating scenario of the solar corona and solar wind.

  15. Thermal projection shielding in teeth flanks of a sugar cane mill drainer of a sugar factory

    Directory of Open Access Journals (Sweden)

    Segundo M. Espín Lagos

    2017-09-01

    Full Text Available Shielding was performed on the flanks of teeth of a cane mill by means of the flame thermal projection technique using the Eutalloy 11496 micropulverized alloy. The material of the toner is AISI 1045 steel and the surface of shielding was prepared by the jet process with abrasive material of volcanic nature, in order to achieve an optimum anchorage surface for the alloy. Next, in software, iterations of the thickness of the shield were realized with the purpose of determining its useful life and through the distribution of Weibull we estimated the function of reliability and the function of probability of failure, considering a complete harvest of 240 days.

  16. Long-period seismic events with strikingly regular temporal patterns on Katla volcano's south flank (Iceland)

    OpenAIRE

    Sgattoni, Giulia; Jeddi, Zeinab; Guðmundsson, Ólafur; Einarsson, Páll; Tryggvason, Ari; LUND, Björn; Lucchi, Federico

    2015-01-01

    Katla is a threatening volcano in Iceland, partly covered by the M\\'yrdalsj\\"okull ice cap. The volcano has a large caldera with several active geothermal areas. A peculiar cluster of long-period seismic events started on Katla's south flank in July 2011, during an unrest episode in the caldera that culminated in a glacier outburst. The seismic events were tightly clustered at shallow depth in the Gvendarfell area, 4 km south of the caldera, under a small glacier stream on the southern margin...

  17. Mitigation of Flanking Noise in Double-Plate Panel Structures by Periodic Stiffening

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal; Dickow, Kristoffer Ahrens; Andersen, Lars

    2011-01-01

    The present analysis focuses on flanking noise transmission within a two-wall structure of finite size. The walls are lightweight panel structures, each consisting of two plates with internal ribs. A finite-element model is utilized, assuming that the studs are fully fixed to the plates. Further......, the air enclosed in the cavities within the structure is taken into consideration, whereas the external air has been disregarded. A fully coupled analysis is performed in which solid finite elements are adopted for the structure, whereas the acoustic medium within the panel is discretized into fluid...

  18. Finite Element Approach for Analyses of Flanking Noise Transmission within Lightweight Panel Structure

    DEFF Research Database (Denmark)

    Domadiya, Parthkumar Gandalal; Dickow, Kristoffer Ahrens; Andersen, Lars

    2011-01-01

    This paper concerns the analysis of noise transmission in a lightweight panel structure. The analysis is based on Finite Element Analysis (FEA) employing solid elements for the structure. The analysis focuses on flanking noise transmission in panel structures of finite size. A parametric study...... and different designs of the ribs regarding the energy contained within the panel strip. The paper presents an analysis of vibrational energy transmission for an isotropic periodic panel strip excited by a concentrated force. The computations are carried out in frequency domain in the range below 2 kHz....

  19. Geochemistry of summit fumarole vapors and flanking thermal/mineral waters at Popocatepetl Volcano, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Werner, C.; Goff, F. [Los Alamos National Lab., NM (United States); Janik, C.J. [Geological Survey, Menlo Park, CA (United States)] [and others

    1997-06-01

    Popocatepetl Volcano is potentially devastating to populations living in the greater Mexico City area. Systematic monitoring of fumarole gases and flanking thermal/mineral springs began in early 1994 after increased fumarolic and seismic activity were noticed in 1991. These investigations had two major objectives: (1) to determine if changes in magmatic conditions beneath Popocatepetl might be reflected by chemical changes in fumarolic discharges and (2) to determine if thermal/mineral spring waters in the vicinity of Popocatepetl are geochemically related to or influences by the magmatic system. This report summarizes results from these two discrete studies.

  20. Reinforcing Deterrence on NATO’s Eastern Flank: Wargaming the Defense of the Baltics

    Science.gov (United States)

    2016-01-01

    SUMMARY ■ C O R P O R A T I O N Reinforcing Deterrence on NATO’s Eastern Flank Wargaming the Defense of the Baltics David A. Shlapak and Michael...that border Russian territory—may be the most problematic. In a series of wargames conducted between summer 2014 and spring 2015, the RAND Corporation...COMMITMENTS Despite President Obama’s bold words in Tallinn, a series of RAND wargames clearly indicates that NATO’s current pos- ture is inadequate

  1. An NSF rotator's perspective: view from inside the hamster wheel

    Science.gov (United States)

    White, Gary

    2015-03-01

    Duncan McBride served as my unofficial mentor during my time at NSF as a ``rotator'' (or, in NSF-speak, an IPA, short for an Intergovernmental Personnel Act assignee), from fall 2012 through summer of 2013. A rotator's main job is to help keep the wheels of the grant submission process turning, shepherding individual proposal jackets through the submission cycle. While most proposals are eventually ``Declined'' it is the few that are funded that evoke the most vivid memories of my time there. I hope to relay a little bit about what that was like on a daily basis, to give one hamster's take on the machinations of the NSF machine, and testify to Duncan McBride's critical role in establishing physics as the leader in disciplinary based educational research (DBER). It was a heady experience in many ways, despite the sheer girth of proposal jackets to be processed and the uncertain footing upon which federal employees tread these days.

  2. Kisspeptin and the seasonal control of reproduction in hamsters

    DEFF Research Database (Denmark)

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

    2008-01-01

    Reproduction is a complex and energy demanding function. When internal and external conditions might impair reproductive success (negative energy balance, stress, harsh season) reproductive activity has to be repressed. Recent evidence suggests that these inhibitory mechanisms operate on Kiss1......-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...... hormone whose secretion is adjusted to night length. The photoperiodic variation in circulating melatonin has been shown to synchronize reproductive activity with seasons, but the mechanisms involved in this effect of melatonin were so far unknown. Recently we have observed that Kiss1 mRNA level...

  3. 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.

  4. Recognition of core and flanking amino acids of MHC class II-bound peptides by the T cell receptor.

    Science.gov (United States)

    Sant'Angelo, Derek B; Robinson, Eve; Janeway, Charles A; Denzin, Lisa K

    2002-09-01

    CD4 T cells recognize peptides bound to major histocompatibility complex (MHC) class II molecules. Most MHC class II molecules have four binding pockets occupied by amino acids 1, 4, 6, and 9 of the minimal peptide epitope, while the residues at positions 2, 3, 5, 7, and 8 are available to interact with the T cell receptor (TCR). In addition MHC class II bound peptides have flanking residues situated outside of this peptide core. Here we demonstrate that the flanking residues of the conalbumin peptide bound to I-A(k) have no effect on recognition by the D10 TCR. To study the role of peptide flanks for recognition by a second TCR, we determined the MHC and TCR contacting amino acids of the I-A(b) bound Ealpha peptide. The Ealpha peptide is shown to bind I-A(b) using four alanines as anchor residues. TCR recognition of Ealpha peptides with altered flanking residues again suggested that, in general, no specific interactions occurred with the peptide flanks. However, using an HLA-DM-mediated technique to measure peptide binding to MHC class II molecules, we found that the peptide flanking residues contribute substantially to MHC binding.

  5. Flank wears Simulation by using back propagation neural network when cutting hardened H-13 steel in CNC End Milling

    Science.gov (United States)

    Hazza, Muataz Hazza F. Al; Adesta, Erry Y. T.; Riza, Muhammad

    2013-12-01

    High speed milling has many advantages such as higher removal rate and high productivity. However, higher cutting speed increase the flank wear rate and thus reducing the cutting tool life. Therefore estimating and predicting the flank wear length in early stages reduces the risk of unaccepted tooling cost. This research presents a neural network model for predicting and simulating the flank wear in the CNC end milling process. A set of sparse experimental data for finish end milling on AISI H13 at hardness of 48 HRC have been conducted to measure the flank wear length. Then the measured data have been used to train the developed neural network model. Artificial neural network (ANN) was applied to predict the flank wear length. The neural network contains twenty hidden layer with feed forward back propagation hierarchical. The neural network has been designed with MATLAB Neural Network Toolbox. The results show a high correlation between the predicted and the observed flank wear which indicates the validity of the models.

  6. Morbidity due to Schistosoma mansoni--Entamoeba histolytica coinfection in hamsters (Mesocricetus auratus)

    National Research Council Canada - National Science Library

    Dolabella, Silvio Santana; Coelho, Paulo Marcos Zech; Borçari, Izabela Torquetti; Mello, Nelson Azevedo Santos Teixeira; Andrade, Zilton de Araújo; Silva, Edward Felix

    2007-01-01

    .... 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...

  7. The daily melatonin pattern in Djungarian hamsters depends on the circadian phenotype.

    Science.gov (United States)

    Schöttner, Konrad; Simonneaux, Valérie; Vuillez, Patrick; Steinlechner, Stephan; Pévet, Paul; Weinert, Dietmar

    2011-12-01

    Djungarian hamsters (Phodopus sungorus) bred at the Institute of Halle reveal three different circadian phenotypes. The wild type (WT) shows normal locomotor activity patterns, whereas in hamsters of the DAO (delayed activity onset) type, the activity onset is continuously delayed. Since the activity offset in those hamsters remains coupled to "light-on," the activity time becomes compressed. Hamsters of the AR (arrhythmic) type are episodically active throughout the 24 h. Previous studies showed that a disturbed interaction of the circadian system with the light-dark (LD) cycle contributes to the phenomenon observed in DAO hamsters. To gain better insight into the underlying mechanisms, the authors investigated the daily melatonin rhythm, as it is a reliable marker of the circadian clock. Hamsters were kept individually under standardized laboratory conditions (LD 14:10, T=22°C±2°C, food and water ad libitum). WT, DAO (with exactly 5 h delay of activity onset), and AR hamsters were used for pineal melatonin and urinary 6-sulfatoxymelatonin (aMT6s) measurement. Pineal melatonin content was determined at 3 time points: 4 h after "light-off" [D+4], 1 h before "light-on" [L-1], and 1h after "light-on" [L+1]). The 24-h profile of melatonin secretion was investigated by transferring the animals to metabolic cages for 27?h to collect urine at 3-h intervals for aMT6s analysis. WT hamsters showed high pineal melatonin content during the dark time (D+4, L-1), which significantly decreased at the beginning of the light period (L+1). In contrast, DAO hamsters displayed low melatonin levels during the part of the dark period when animals were still resting (D+4). At the end of the dark period (L-1), melatonin content increased significantly and declined again when light was switched on (L+1). AR hamsters showed low melatonin levels, comparable to daytime values, at all 3 time points. The results were confirmed by aMT6s data. WT hamsters showed a marked circadian pattern of

  8. Beneficial effects of noni (Morinda citrifolia L.) juice on livers of high-fat dietary hamsters.

    Science.gov (United States)

    Lin, Yi-Ling; Chang, Yuan-Yen; Yang, Deng-Jye; Tzang, Bor-Show; Chen, Yi-Chen

    2013-09-01

    Polyphenols in noni juice (NJ) are mainly composed of phenolic acids, mainly gentisic, p-hydroxybenoic, and chlorogenic acids. To investigate the beneficial effects of NJ on the liver, hamsters were fed with two diets, normal-fat and high-fat diets. Furthermore, high-fat dietary hamsters were received distilled water, and 3, 6, and 9 mL NJ/kg BW, respectively. After a 6-week feeding period, the increased (phamsters compared to the control hamsters were ameliorated (phamsters. High-fat dietary hamsters supplemented with NJ had higher (p<0.05) liver antioxidant capacities but lowered (p<0.05) liver iNOS, COX-2, TNF-α, and IL-1β expressions, gelatinolytic levels of MMP9, and serum ALT values compared to those without NJ. Hence, NJ protects liver against a high-fat dietary habit via regulations of antioxidative and anti-inflammatory responses. Copyright © 2013 Elsevier Ltd. All rights reserved.

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

    NARCIS (Netherlands)

    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

    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,

  10. 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

  11. 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.

  12. Capsaicinoids lower plasma cholesterol and improve endothelial function in hamsters.

    Science.gov (United States)

    Liang, Yin Tong; Tian, Xiao-Yu; Chen, Jing Nan; Peng, Cheng; Ma, Ka Ying; Zuo, Yuanyuan; Jiao, Rui; Lu, Ye; Huang, Yu; Chen, Zhen-Yu

    2013-02-01

    Capsaicinoids are the active compounds in chili pepper. The present study investigated the effect of capsaicinoids on plasma lipids, functionality of aorta including atherosclerotic plaque development, cholesterol absorption biomarker, fecal sterol excretion, and gene expression of major receptors, enzymes, and transporters involved in cholesterol metabolism. Hamsters were divided into five groups and fed a high-cholesterol diet containing 0 % (CON), 0.010 % (LD), 0.015 % (MD), 0.020 % (HD), and 0.030 % (VD) capsaicinoids, respectively, for 6 weeks. Plasma lipids were measured using the enzymatic kits, and the gene expression of transporters, enzymes, and receptors involved in cholesterol absorption and metabolism was quantified using the quantitative PCR. Endothelial function was assessed by measuring the acetylcholine-induced endothelium-dependent relaxations in aorta. Capsaicinoids reduced plasma total cholesterol, non-high-density lipoprotein cholesterol, and triacylglycerols with high-density lipoprotein cholesterol being unaffected. All four experimental groups had a decrease in the atherosclerotic plaque compared with CON. Dietary capsaicinoids increased the fecal excretion of total acidic sterols possibly mediated by up-regulation of cholesterol 7α-hydroxylase and down-regulation of liver X receptor alpha. Plasma sterol analysis demonstrated that capsaicinoids decreased the ratio of plasma campesterol/cholesterol, suggesting they decreased cholesterol absorption. Capsaicinoids could improve the endothelium-dependent relaxations and reduce the endothelium-dependent contractions by inhibiting the gene expression of COX-2. However, no dose-dependent effect of capsaicinoids on these parameters was seen. Capsaicinoids were beneficial in improving lipoprotein profile and aortic function in hamsters fed a high-cholesterol diet.

  13. Fluoxetine disrupts motivation and GABAergic signaling in adolescent female hamsters.

    Science.gov (United States)

    Shannonhouse, John L; DuBois, Dustin W; Fincher, Annette S; Vela, Alejandra M; Henry, Morgan M; Wellman, Paul J; Frye, Gerald D; Morgan, Caurnel

    2016-08-01

    Initial antidepressant treatment can paradoxically worsen symptoms in depressed adolescents by undetermined mechanisms. Interestingly, antidepressants modulate GABAA receptors, which mediate paradoxical effects of other therapeutic drugs, particularly in females. Although the neuroanatomic site of action for this paradox is unknown, elevated GABAA receptor signaling in the nucleus accumbens can disrupt motivation. We assessed fluoxetine's effects on motivated behaviors in pubescent female hamsters - anhedonia in the reward investigational preference (RIP) test as well as anxiety in the anxiety-related feeding/exploration conflict (AFEC) test. We also assessed accumbal signaling by RT-PCR and electrophysiology. Fluoxetine initially worsened motivated behaviors at puberty, relative to adulthood. It also failed to improve these behaviors as pubescent hamsters transitioned into adulthood. Low accumbal mRNA levels of multiple GABAA receptor subunits and GABA-synthesizing enzyme, GAD67, assessed by RT-PCR, suggested low GABAergic tone at puberty. Nonetheless, rapid fluoxetine-induced reductions of α5GABAA receptor and BDNF mRNA levels at puberty were consistent with age-related differences in GABAergic responses to fluoxetine and disruption of the motivational state. Whole-cell patch clamping of accumbal slices also suggested low GABAergic tone by the low amplitude of miniature inhibitory postsynaptic currents (mIPSCs) at puberty. It also confirmed age-related differences in GABAergic responses to fluoxetine. Specifically, fluoxetine potentiated mIPSC amplitude and frequency at puberty, but attenuated the amplitude during adulthood. These results implicate GABAergic tone and GABAA receptor plasticity in adverse motivational responses and resistance to fluoxetine during adolescence. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. 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

  15. 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...... of this genetic diversity highlight the value of the hamster genome as the reference upon which CHO cells can be studied and engineered for protein production....

  16. Serum leptin, energy budget, and thermogenesis in striped hamsters exposed to consecutive decreases in ambient temperatures.

    Science.gov (United States)

    Zhao, Zhi-Jun

    2011-01-01

    Leptin has been found to be a direct participant in the regulation of both energy intake and energy expenditure in small mammals showing seasonal declines in body mass (M(b)) and fat mass, but its roles in an animal exhibiting seasonally increased thermogenesis and unchanged M(b) remain unclear. Serum leptin levels, energy budget, and thermogenesis were measured in striped hamsters exposed to consecutive decreases in ambient temperatures ranging from 23° to -23°C. Cold-exposed hamsters had significant increases in gross energy intake (GEI), the rate of basal metabolism, nonshivering thermogenesis, and activity of cytochrome c oxidase (COX) in brown adipose tissue (BAT), compared with control hamsters, indicating a cold-induced elevation of thermogenesis. Body mass and fat content were decreased in cold-exposed animals, and serum leptin levels were increased in hamsters exposed to temperatures of -8°C and below in inverse proportion to body fat content. Serum leptin levels were positively correlated with GEI and BAT COX activity in cold-exposed hamsters, but no such relationships were observed in control animals. These findings suggest that cold-exposed hamsters increase food consumption to meet the energy requirements for increased BAT thermogenesis. The increases in serum leptin levels are likely involved in increased thermogenesis in hamsters under cold stress. Cold-exposed hamsters may become leptin resistant, which is associated with impaired regulation of food intake. This new natural model of leptin resistance may also provide insight into the dynamic long-term control of energy homeostasis for animals that do not exhibit seasonal decline in M(b).

  17. CpG oligodeoxynucleotides with crude parasite antigens reduce worm recovery in Opisthorchis viverrini infected hamsters.

    Science.gov (United States)

    Kaewraemruaen, Chamraj; Sermswan, Rasana W; Wongratanacheewin, Surasakdi

    2016-12-01

    Opisthorchis viverrini, a human liver fluke, is still an endemic parasitic infection in Thailand and nearly all countries in Southeast Asia. O. viverrini induces a chronic stage of infection in hamsters. During the first 2 weeks of infection, Th1 inducing cytokine, IL-12, increased but was down regulated in chronic infection. In this study it was found that unmethylated-CpG ODN (oligodeoxynucleotides) 1826 increased hamster mononuclear cell proliferation and stimulated IFN-γ production in vitro. The IFN-γ levels in hamster sera were significantly increased in hamsters injected with CpG ODN 1826 alone or plus crude somatic antigens (CSAg). Further investigation using the flow cytometer found that CD4(+)T cells and IFN-γ(+) CD4(+)T cells (Th1-like cells) in the hamster blood were significantly increased. The role of these cells in the protective responses in hamsters was evaluated by challenging with 25 metacercaria and observation for 3 months. The number of worms recovered was significantly reduced in the hamsters injected with CpG ODN 1826 with CSAg, but not in CpG ODN 1826 alone groups when compared to PBS control. The percent of reduction in hamsters against this parasite were 32.95% and 21.49% in the CpG ODN 1826 with CSAg and CpG ODN 1826 alone. This study indicates that CpG ODN 1826 plus parasite antigens elicit a Th1-like response that leads to the enhancement of worm reduction. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Leptin mediates seasonal variation in some but not all symptoms of sickness in Siberian hamsters.

    Science.gov (United States)

    Carlton, Elizabeth D; Demas, Gregory E

    2014-11-01

    Many seasonally breeding species, including Siberian hamsters (Phodopus sungorus), exhibit seasonal variation in sickness responses. One hypothesis regarding the mechanism of this variation is that sickness intensity tracks an animal's energetic state, such that sickness is attenuated in the season that an animal has the lowest fat stores. Energetic state may be signaled via leptin, an adipose hormone that provides a signal of fat stores. Siberian hamsters respond to extended housing in short, winter-like days by reducing fat stores and leptin levels, relative to those housed in long, summer-like days. Sickness responses are also attenuated in short-day hamsters as compared to long-day hamsters. We hypothesized that leptin provides a physiological signal by which seasonally breeding animals modulate sickness responses, such that animals with higher leptin levels show increased sickness intensity. To test this, we provided short-day hamsters with a long-day-like leptin signal and assessed their responses to lipopolysaccharide (LPS), a sickness-inducing antigen. We compared these responses to short-day vehicle-, long-day vehicle-, and long-day leptin-treated hamsters. Unexpectedly, LPS induced a hypothermic response (rather than fever) in all groups. Short-day vehicle-treated hamsters exhibited the greatest LPS-induced hypothermia, and leptin treatment attenuated this response, making hypothermia more long-day-like. Contrary to our hypothesis, short-day leptin-treated hamsters showed the least pronounced LPS-induced anorexia among all groups. These results suggest that leptin may mediate some but not all aspects of seasonal sickness variation in this species. Future studies should be targeted at determining roles of other energetic hormones in regulating seasonal sickness response variation. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Use of hamster as a model to study diet-induced atherosclerosis

    OpenAIRE

    Lichtenstein Alice H; Matthan Nirupa R; Dillard Alice

    2010-01-01

    Abstract Golden-Syrian hamsters have been used as an animal model to assess diet-induced atherosclerosis since the early 1980s. Advantages appeared to include a low rate of endogenous cholesterol synthesis, receptor-mediated uptake of LDL cholesterol, cholesteryl ester transfer protein activity, hepatic apoB-100 and intestinal apoB-48 secretion, and uptake of the majority of LDL cholesterol via the LDL receptor pathway. Early work suggested hamsters fed high cholesterol and saturated fat diet...

  20. Use of hamster as a model to study diet-induced atherosclerosis

    Directory of Open Access Journals (Sweden)

    Lichtenstein Alice H

    2010-12-01

    Full Text Available Abstract Golden-Syrian hamsters have been used as an animal model to assess diet-induced atherosclerosis since the early 1980s. Advantages appeared to include a low rate of endogenous cholesterol synthesis, receptor-mediated uptake of LDL cholesterol, cholesteryl ester transfer protein activity, hepatic apoB-100 and intestinal apoB-48 secretion, and uptake of the majority of LDL cholesterol via the LDL receptor pathway. Early work suggested hamsters fed high cholesterol and saturated fat diets responded similarly to humans in terms of lipoprotein metabolism and aortic lesion morphology. Recent work has not consistently replicated these findings. Reviewed was the literature related to controlled hamster feeding studies that assessed the effect of strain, background diet (non-purified, semi-purified and dietary perturbation (cholesterol and/or fat on plasma lipoprotein profiles and atherosclerotic lesion formation. F1B hamsters fed a non-purified cholesterol/fat-supplemented diet had more atherogenic lipoprotein profiles (nHDL-C > HDL-C than other hamster strains or hamsters fed cholesterol/fat-supplemented semi-purified diets. However, fat type; saturated (SFA, monounsaturated or n-6 polyunsaturated (PUFA had less of an effect on plasma lipoprotein concentrations. Cholesterol- and fish oil-supplemented semi-purified diets yielded highly variable results when compared to SFA or n-6 PUFA, which were antithetical to responses observed in humans. Dietary cholesterol and fat resulted in inconsistent effects on aortic lipid accumulation. No hamster strain was reported to consistently develop lesions regardless of background diet, dietary cholesterol or dietary fat type amount. In conclusion, at this time the Golden-Syrian hamster does not appear to be a useful model to determine the mechanism(s of diet-induced development of atherosclerotic lesions.

  1. Use of hamster as a model to study diet-induced atherosclerosis.

    Science.gov (United States)

    Dillard, Alice; Matthan, Nirupa R; Lichtenstein, Alice H

    2010-12-10

    Golden-Syrian hamsters have been used as an animal model to assess diet-induced atherosclerosis since the early 1980s. Advantages appeared to include a low rate of endogenous cholesterol synthesis, receptor-mediated uptake of LDL cholesterol, cholesteryl ester transfer protein activity, hepatic apoB-100 and intestinal apoB-48 secretion, and uptake of the majority of LDL cholesterol via the LDL receptor pathway. Early work suggested hamsters fed high cholesterol and saturated fat diets responded similarly to humans in terms of lipoprotein metabolism and aortic lesion morphology. Recent work has not consistently replicated these findings. Reviewed was the literature related to controlled hamster feeding studies that assessed the effect of strain, background diet (non-purified, semi-purified) and dietary perturbation (cholesterol and/or fat) on plasma lipoprotein profiles and atherosclerotic lesion formation. F1B hamsters fed a non-purified cholesterol/fat-supplemented diet had more atherogenic lipoprotein profiles (nHDL-C > HDL-C) than other hamster strains or hamsters fed cholesterol/fat-supplemented semi-purified diets. However, fat type; saturated (SFA), monounsaturated or n-6 polyunsaturated (PUFA) had less of an effect on plasma lipoprotein concentrations. Cholesterol- and fish oil-supplemented semi-purified diets yielded highly variable results when compared to SFA or n-6 PUFA, which were antithetical to responses observed in humans. Dietary cholesterol and fat resulted in inconsistent effects on aortic lipid accumulation. No hamster strain was reported to consistently develop lesions regardless of background diet, dietary cholesterol or dietary fat type amount. In conclusion, at this time the Golden-Syrian hamster does not appear to be a useful model to determine the mechanism(s) of diet-induced development of atherosclerotic lesions.

  2. 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.

  3. Somatostatin Agonist Pasireotide Inhibits Exercise-Stimulated Growth in the Male Siberian Hamster (Phodopus sungorus).

    Science.gov (United States)

    Dumbell, R; Petri, I; Scherbarth, F; Diedrich, V; Schmid, H A; Steinlechner, S; Barrett, P

    2017-01-01

    The Siberian hamster (Phodopus sungorus) is a seasonal mammal, exhibiting a suite of physiologically and behaviourally distinct traits dependent on the time of year and governed by changes in perceived day length (photoperiod). These attributes include significant weight loss, reduced food intake, gonadal atrophy and pelage change with short-day photoperiod as in winter. The central mechanisms driving seasonal phenotype change during winter are mediated by a reduced availability of hypothalamic triiodothyronine (T3), although the downstream mechanisms responsible for physiological and behavioural changes are yet to be fully clarified. With access to a running wheel (RW) in short photoperiod, Siberian hamsters that have undergone photoperiod-mediated weight loss over-ride photoperiod-drive for reduced body weight and regain weight similar to a hamster held in long days. These changes occur despite retaining the majority of hypothalamic gene expression profiles appropriate for short-day hamsters. Utilising the somatostatin agonist pasireotide, we recently provided evidence for an involvement of the growth hormone (GH) axis in the seasonal regulation of bodyweight. In the present study, we employed pasireotide to test for the possible involvement of the GH axis in RW-induced body weight regulation. Pasireotide successfully inhibited exercise-stimulated growth in short-day hamsters and this was accompanied by altered hypothalamic gene expression of key GH axis components. Our data provide support for an involvement of the GH axis in the RW response in Siberian hamsters. © 2016 British Society for Neuroendocrinology.

  4. Results of phenol red thread test in clinically normal Syrian hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Rajaei, Seyed Mehdi; Sadjadi, Reza; Sabzevari, Amin; Ghaffari, M Selk

    2013-11-01

    To determine the normal reference range for phenol red thread test (PRTT) values in clinically normal Syrian hamsters (Mesocricetus auratus). Sixteen healthy adult Syrian hamsters (eight males and eight females) were used in this study. Ophthalmic examinations were performed without chemical restraint. PRTT values were evaluated in both eyes of all Syrian hamsters using a commercial PRTT strip of a single lot number. No statistically significant differences between right and left eyes were found for any of the results. The mean ± SD PRTT values for the study population were 6.8 ± 2.5 mm/15 s with a range from 3 to 11.5 mm/15 s. Mean PRTTs in male animals were 5.1 ± 1.2 mm/15 s, whereas mean PRTTs in female hamsters were 8.5 ± 2.3 mm/15 s. Comparison between mean PRTT values in males and females showed a significant difference (P = 0.004). Mean weights for males and females were 80.9 ± 4.8 and 90.6 ± 8.5 g, respectively. No linear relationship between mean PRTT and body weight was found in female (P = 0.46) and male (P = 0.92) hamsters. This study provides novel data for normal reference ranges of PRTT values in healthy Syrian hamsters. Results of this study may assist veterinarians in the diagnosis of ocular surface disease and syndromes affecting the tear film in these species. © 2013 American College of Veterinary Ophthalmologists.

  5. Free-running circadian period does not shorten with age in female Syrian hamsters.

    Science.gov (United States)

    Duffy, J F; Viswanathan, N; Davis, F C

    1999-08-20

    It has been reported that the free-running period of circadian rhythms shortens with age in mammals, including humans, and this shortening has been suggested to be the underlying cause of early morning awakening and difficulty maintaining sleep in older people. A recent study found that the free-running period of male hamsters does not change with age. The present study extends those findings to female hamsters. We studied the locomotor activity rhythm of 22 female hamsters kept in constant conditions from early adulthood until their death, and compared their data to those from male hamsters. We found no shortening of free-running period with age in the female hamsters, and no difference in free-running period between females and males. In contrast, mean activity level and amount of time per cycle spent running declined with age in females and males. These findings demonstrate that the free-running period in hamsters does not systematically shorten with age, and suggest that alternative explanations for the observed age-related advance of sleep-wake times in humans should be explored.

  6. Performance of genotype imputation for rare variants identified in exons and flanking regions of genes.

    Directory of Open Access Journals (Sweden)

    Li Li

    Full Text Available Genotype imputation has the potential to assess human genetic variation at a lower cost than assaying the variants using laboratory techniques. The performance of imputation for rare variants has not been comprehensively studied. We utilized 8865 human samples with high depth resequencing data for the exons and flanking regions of 202 genes and Genome-Wide Association Study (GWAS data to characterize the performance of genotype imputation for rare variants. We evaluated reference sets ranging from 100 to 3713 subjects for imputing into samples typed for the Affymetrix (500K and 6.0 and Illumina 550K GWAS panels. The proportion of variants that could be well imputed (true r(2>0.7 with a reference panel of 3713 individuals was: 31% (Illumina 550K or 25% (Affymetrix 500K with MAF (Minor Allele Frequency less than or equal 0.001, 48% or 35% with 0.0010.05. The performance for common SNPs (MAF>0.05 within exons and flanking regions is comparable to imputation of more uniformly distributed SNPs. The performance for rare SNPs (0.01

  7. Variants within the 5'-flanking region and the intron I of the bovine growth hormone gene.

    Science.gov (United States)

    Hecht, C; Geldermann, H

    1996-10-01

    In order to identify DNA variants potentially involved in the regulation of the expression of the bovine growth hormone gene, the 5'-flanking, the 5'-untranslated and the signal peptide coding regions of 15 cows (four German Friesian, two German Simmental, two Jersey, two Galloway, two Scottish Highland, two Charolais and one Ceylon Dwarf Zebu) were analysed. For each animal a region of about 1.2 kb was amplified by polymerase chain reaction (PCR) and sequenced. Six sites of variable nucleotides were identified in the 5'-flanking region of the gene and one in the intron I. Some of these variable sites are also potential binding sites for trans-acting factors (CAAT/enhancer binding protein (C/EBP), polyoma virus enhancer A binding protein 3 (PEA3), thyroid hormone response element (TRE)) and therefore possibly involved in the expression of the growth hormone gene. PCR amplification of specific alleles (PASA) tests for two of the sites (G2, G3) were established and the genotypes for these variants were analysed in 190 cows. The frequencies of the C alleles of the sites G2 and G3 were 0.63 and 0.76, respectively.

  8. Identification of functional SNPs in the 5-prime flanking sequences of human genes

    Directory of Open Access Journals (Sweden)

    Lenhard Boris

    2005-02-01

    Full Text Available Abstract Background Over 4 million single nucleotide polymorphisms (SNPs are currently reported to exist within the human genome. Only a small fraction of these SNPs alter gene function or expression, and therefore might be associated with a cell phenotype. These functional SNPs are consequently important in understanding human health. Information related to functional SNPs in candidate disease genes is critical for cost effective genetic association studies, which attempt to understand the genetics of complex diseases like diabetes, Alzheimer's, etc. Robust methods for the identification of functional SNPs are therefore crucial. We report one such experimental approach. Results Sequence conserved between mouse and human genomes, within 5 kilobases of the 5-prime end of 176 GPCR genes, were screened for SNPs. Sequences flanking these SNPs were scored for transcription factor binding sites. Allelic pairs resulting in a significant score difference were predicted to influence the binding of transcription factors (TFs. Ten such SNPs were selected for mobility shift assays (EMSA, resulting in 7 of them exhibiting a reproducible shift. The full-length promoter regions with 4 of the 7 SNPs were cloned in a Luciferase based plasmid reporter system. Two out of the 4 SNPs exhibited differential promoter activity in several human cell lines. Conclusions We propose a method for effective selection of functional, regulatory SNPs that are located in evolutionary conserved 5-prime flanking regions (5'-FR regions of human genes and influence the activity of the transcriptional regulatory region. Some SNPs behave differently in different cell types.

  9. Characterization of Bovine 5′-flanking Region during Differentiation of Mouse Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Hye-Jeong Jang

    2015-12-01

    Full Text Available Embryonic stem cells (ESCs have been used as a powerful tool for research including gene manipulated animal models and the study of developmental gene regulation. Among the critical regulatory factors that maintain the pluripotency and self-renewal of undifferentiated ESCs, NANOG plays a very important role. Nevertheless, because pluripotency maintaining factors and specific markers for livestock ESCs have not yet been probed, few studies of the NANOG gene from domestic animals including bovine have been reported. Therefore, we chose mouse ESCs in order to understand and compare NANOG expression between bovine, human, and mouse during ESCs differentiation. We cloned a 600 bp (−420/+181 bovine NANOG 5′-flanking region, and tagged it with humanized recombinant green fluorescent protein (hrGFP as a tracing reporter. Very high GFP expression for bovine NANOG promoter was observed in the mouse ESC line. GFP expression was monitored upon ESC differentiation and was gradually reduced along with differentiation toward neurons and adipocyte cells. Activity of bovine NANOG (−420/+181 promoter was compared with already known mouse and human NANOG promoters in mouse ESC and they were likely to show a similar pattern of regulation. In conclusion, bovine NANOG 5-flanking region functions in mouse ES cells and has characteristics similar to those of mouse and human. These results suggest that bovine gene function studied in mouse ES cells should be evaluated and extrapolated for application to characterization of bovine ES cells.

  10. Phylogenetic inference and comparative evolution of a complex microsatellite and its flanking regions in carnivores.

    Science.gov (United States)

    Domingo-Roura, Xavier; López-Giráldez, Francesc; Saeki, Midori; Marmi, Josep

    2005-06-01

    We sequenced locus Mel 08, with complex short repetitive motifs, in 24 carnivore species belonging to five different families in order to explore mutational changes in the region in the context of locus and species evolution. This non-coding locus includes up to four different parts or repetitive motifs showing size variability. The variability consists of repeat additions and deletions; substitutions, insertions and/or deletions creating interruptions in the repeat; and substitutions, insertions and deletions in the flanking regions. The locus has different repeat expansions in different carnivore subfamilies. We hypothesize that the complexity of this locus is due to a high mutation rate at an ancestral DNA sequence and, thus, prompts the emergence of repeats at mutational hotspots. High levels of homoplasy were evident, with nine electromorphs representing 28 haplotypes never shared across species. The variability in flanking regions was informative for phylogenetic inference and their evolutionary content. Tree topologies were congruent with relevant hypotheses on current conflicts in carnivore phylogenies, such as: (i) the monophyly of Lutrinae, (ii) the paraphyly of Mustelinae, (iii) the basal position of the Eurasian badger, Meles meles , in the Mustelidae, (iv) the classification of skunks as a separate family, Mephitidae, and (v) the placement of the red panda, Ailurus fulgens , as a monotypic family, Ailuridae, at a basal position in the Musteloidea.

  11. Sequence Analysis of SSR-Flanking Regions Identifies Genome Affinities between Pasture Grass Fungal Endophyte Taxa

    Directory of Open Access Journals (Sweden)

    Eline van Zijll de Jong

    2011-01-01

    Full Text Available Fungal species of the Neotyphodium and Epichloë genera are endophytes of pasture grasses showing complex differences of life-cycle and genetic architecture. Simple sequence repeat (SSR markers have been developed from endophyte-derived expressed sequence tag (EST collections. Although SSR array size polymorphisms are appropriate for phenetic analysis to distinguish between taxa, the capacity to resolve phylogenetic relationships is limited by both homoplasy and heteroploidy effects. In contrast, nonrepetitive sequence regions that flank SSRs have been effectively implemented in this study to demonstrate a common evolutionary origin of grass fungal endophytes. Consistent patterns of relationships between specific taxa were apparent across multiple target loci, confirming previous studies of genome evolution based on variation of individual genes. Evidence was obtained for the definition of endophyte taxa not only through genomic affinities but also by relative gene content. Results were compatible with the current view that some asexual Neotyphodium species arose following interspecific hybridisation between sexual Epichloë ancestors. Phylogenetic analysis of SSR-flanking regions, in combination with the results of previous studies with other EST-derived SSR markers, further permitted characterisation of Neotyphodium isolates that could not be assigned to known taxa on the basis of morphological characteristics.

  12. Renal infarction versus pyelonephritis in a woman presenting with fever and flank pain.

    Science.gov (United States)

    Piccoli, Giorgina B; Priola, Adriano M; Vigotti, Federica N; Guzzo, Gabriella; Veltri, Andrea

    2014-08-01

    Patients with fever, flank pain, and dysuria frequently are encountered in the emergency department. Acute pyelonephritis is the most likely diagnosis; however, its clinical and radiologic presentation consistently overlap with that of acute renal infarction. Ultrasound is unable to distinguish early infarction from nonabscessed acute pyelonephritis. Hence, computed tomography or magnetic resonance imaging are needed. We report the case of a 68-year-old woman who presented with fever, flank pain, and dysuria, along with respiratory distress and tachycardia. Elevated values for inflammatory indexes suggested a diagnosis of acute pyelonephritis, and subsequent contrast-enhanced computed tomography showed hypodense wedge-shaped areas in both kidneys. However, the presence of a thin rim of capsular enhancement (cortical rim sign), the absence of perirenal inflammatory changes, and the location of the lesions apart from defined calyces suggested the alternative diagnosis of renal infarction. The underlying cause was not identified until an episode of acute dyspnea revealed paroxysmal arrhythmia. Our case demonstrates that a thorough knowledge of the imaging findings of renal infarction and acute pyelonephritis is essential to correctly making the diagnosis. Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  13. Delayed deficits in behavior after transection of the olfactory tracts in hamsters.

    Science.gov (United States)

    Marques, D M; O'Connell, R J; Benimoff, N; Macrides, F

    1982-02-01

    This study compared the effects of transection of the lateral olfactory tracts (LOT) and the accessory olfactory tracts (AOT) in male hamsters on nest building, food piling, and sexual behavior. Autoradiographic tracing of amino acids injected into the olfactory bulbs allowed accurate determination of the location and extent of the transections. Animals with complete bilateral transection of the projections to the amygdaloid targets of the accessory olfactory bulbs and to the main olfactory targets posterior to the olfactory tubercle showed no sexual behavior postoperatively; they did not exhibit extensive genital investigation and did not mount females. In contrast, most of the animals with partial sparing of accessory olfactory bulb efferents to the amygdala did exhibit investigatory and copulatory behaviors postoperatively, although half of the animals with this partial sparing developed delayed deficits in these sexual behaviors. Almost all animals without detectable main olfactory bulb efferents to posterior targets showed delayed deficits in nest building and food piling. This was true whether or not there was partial sparing of accessory olfactory bulb efferents to the amygdala. The animals with LOT transections typically built nests and piled food during the first postoperative week, but stopped building nests and piling food by the fourth postoperative week. Cold stress enhanced these two behaviors in control animals but did not obviate the deficits in experimental animals. Caudally placed transections, which spared a larger portion of the main olfactory projections than rostally placed transections, did not spare more behavior. In fact, the caudally placed transections produced shorter delays in the appearance of deficits in nest building and food piling. These results indicate that the accessory olfactory bulb efferents to the amygdala are more important for sexual behavior than for nest building and food piling in male hamsters. Nest building and food

  14. Entamoeba histolytica: liver invasion and abscess production by intraperitoneal inoculation of trophozoites in hamsters, Mesocricetus auratus.

    Science.gov (United States)

    Shibayama, M; Campos-Rodríguez, R; Ramírez-Rosales, A; Flores-Romo, L; Espinosa-Cantellano, M; Martínez-Palomo, A; Tsutsumi, V

    1998-01-01

    Intraperitoneal inoculation of axenically cultured Entamoeba histolytica trophozoites constitutes an easy to perform, highly reproducible procedure for inducing amebic liver abscesses in hamsters. Efficiency in abscess production (95% of infected animals after 1 week) was similar to data reported using direct intrahepatic or intraportal inoculation. The morphological sequence of infection shows that amebas in the peritoneal cavity initially produce a large exudate constituted mainly of acute inflammatory cells. These cells form a rim of polymorphonuclear leukocytes surrounding the amebas, which adhere to the trophozoite and can sometimes be observed polarized to one end of the parasite, suggesting capping of surface receptors. Early stages are also characterized by the production of distant inflammatory reactions in the hepatic portal spaces. At 6 h postintraperitoneal inoculation, larger foci of inflammatory reactions surrounding amebas are developed in the peritoneum, extending to and damaging the liver surface membranes as well as the serosa of other internal organs. Thereafter, tissue damage progresses deeper into the liver parenchyma, and a few days later, coalescing granulomas and large necrotic areas are observed in the liver tissue. Based on the present morphological time-sequence study, we suggest that inflammatory cells associated with E. histolytica trophozoites play an important role in commencing the damage of liver sheaths and producing the subsequent parenchymal lesions. The simplicity and reliability of this model are important factors to consider when large numbers of experimentally induced amebic liver abscesses are needed.

  15. Cholesterol-lowering properties of Ganoderma lucidum in vitro, ex vivo, and in hamsters and minipigs

    Directory of Open Access Journals (Sweden)

    Hajjaj H

    2004-02-01

    Full Text Available Abstract Introduction There has been renewed interest in mushroom medicinal properties. We studied cholesterol lowering properties of Ganoderma lucidum (Gl, a renowned medicinal species. Results Organic fractions containing oxygenated lanosterol derivatives inhibited cholesterol synthesis in T9A4 hepatocytes. In hamsters, 5% Gl did not effect LDL; but decreased total cholesterol (TC 9.8%, and HDL 11.2%. Gl (2.5 and 5% had effects on several fecal neutral sterols and bile acids. Both Gl doses reduced hepatic microsomal ex-vivo HMG-CoA reductase activity. In minipigs, 2.5 Gl decreased TC, LDL- and HDL cholesterol 20, 27, and 18%, respectively (P Conclusions Overall, Gl has potential to reduce LDL cholesterol in vivo through various mechanisms. Next steps are to: fully characterize bioactive components in lipid soluble/insoluble fractions; evaluate bioactivity of isolated fractions; and examine human cholesterol lowering properties. Innovative new cholesterol-lowering foods and medicines containing Gl are envisioned.

  16. Morphologic observations of experimental Campylobacter jejuni infection in the hamster intestinal tract.

    Science.gov (United States)

    Humphrey, C. D.; Montag, D. M.; Pittman, F. E.

    1986-01-01

    The authors have developed a model for the diarrhea and intestinal lesions seen in Campylobacter jejuni enterocolitis by colonizing the hamster ileum and cecum with C jejuni. Erythematous inflammation of the ileum and cecum and distention of the cecum with fluid were observed at autopsy. The cecal mucosa appeared edematous. Epithelial abnormalities observed by light microscopy included focal edema, occasional hyperplasia, diffuse hyperemia, and infiltration of the lamina propria with leukocytes. C jejuni-like bacteria penetrated the epithelium and were seen in the lamina propria of infected animals but not in uninfected controls. Diverse microvillus lesions, including elongation, shortening, blebbing, and denudation, were seen by transmission electron microscopy. Occasional cytoplasmic aberrations included vacuoles, some containing C jejuni-like bacteria, swollen endoplasmic reticulum, and enlarged mitochondria. Campylobacter structures were vibrio and S-shaped types. Some C jejuni organisms had corrugated screwlike structures wrapped around their circumferences. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 PMID:3942198

  17. Valganciclovir Inhibits Human Adenovirus Replication and Pathology in Permissive Immunosuppressed Female and Male Syrian Hamsters

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    Karoly Toth

    2015-03-01

    Full Text Available Adenovirus infections of immunocompromised pediatric hematopoietic stem cell transplant patients can develop into serious and often deadly multi-organ disease. There are no drugs approved for adenovirus infections. Cidofovir (an analog of 2-deoxycytidine monophosphate is used at times but it can be nephrotoxic and its efficacy has not been proven in clinical trials. Brincidofovir, a promising lipid-linked derivative of cidofovir, is in clinical trials. Ganciclovir, an analog of 2-deoxyguanosine, has been employed occasionally but with unknown efficacy in the clinic. In this study, we evaluated valganciclovir against disseminated adenovirus type 5 (Ad5 infection in our permissive immunosuppressed Syrian hamster model. We administered valganciclovir prophylactically, beginning 12 h pre-infection or therapeutically starting at Day 1, 2, 3, or 4 post-infection. Valganciclovir significantly increased survival, reduced viral replication in the liver, and mitigated the pathology associated with Ad5 infection. In cultured cells, valganciclovir inhibited Ad5 DNA replication and blocked the transition from early to late stage of infection. Valganciclovir directly inhibited Ad5 DNA polymerase in vitro, which may explain, at least in part, its mechanism of action. Ganciclovir and valganciclovir are approved to treat infections by certain herpesviruses. Our results support the use of valganciclovir to treat disseminated adenovirus infections in immunosuppressed patients.

  18. Distinctive Profiles of Infection and Pathology in Hamsters Infected with Clostridium difficile Strains 630 and B1 ▿

    OpenAIRE

    Goulding, David; Thompson, Harold; Emerson, Jenny; Fairweather, Neil F.; Dougan, Gordon; Douce, Gill R.

    2009-01-01

    Currently, the Golden Syrian hamster is widely considered an important model of Clostridium difficile disease, as oral infection of this animal pretreated with antibiotics reproduces many of the symptoms observed in humans. Two C. difficile strains, B1 and 630, showed significant differences in the progression and severity of disease in this model. B1-infected hamsters exhibited more severe pathology and a shorter time to death than hamsters infected with 630. Histological changes in the gut ...

  19. A novel regulatory element (E77) isolated from CHO-K1 genomic DNA enhances stable gene expression in Chinese hamster ovary cells.

    Science.gov (United States)

    Kang, Shin-Young; Kim, Yeon-Gu; Kang, Seunghee; Lee, Hong Weon; Lee, Eun Gyo

    2016-05-01

    Vectors flanked by regulatory DNA elements have been used to generate stable cell lines with high productivity and transgene stability; however, regulatory elements in Chinese hamster ovary (CHO) cells, which are the most widely used mammalian cells in biopharmaceutical production, are still poorly understood. We isolated a novel gene regulatory element from CHO-K1 cells, designated E77, which was found to enhance the stable expression of a transgene. A genomic library was constructed by combining CHO-K1 genomic DNA fragments with a CMV promoter-driven GFP expression vector, and the E77 element was isolated by screening. The incorporation of the E77 regulatory element resulted in the generation of an increased number of clones with high expression, thereby enhancing the expression level of the transgene in the stable transfectant cell pool. Interestingly, the E77 element was found to consist of two distinct fragments derived from different locations in the CHO genome shotgun sequence. High and stable transgene expression was obtained in transfected CHO cells by combining these fragments. Additionally, the function of E77 was found to be dependent on its site of insertion and specific orientation in the vector construct. Our findings demonstrate that stable gene expression mediated by the CMV promoter in CHO cells may be improved by the isolated novel gene regulatory element E77 identified in the present study. © 2016 The Authors. Biotechnology Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Experimental Infection of the Skin in the Hamster Simulating Human Impetigo IV. Cellular Responses after Streptococcal and Staphylococcal Infections

    Science.gov (United States)

    Dajani, Adnan S.; Wannamaker, Lewis W.

    1972-01-01

    Various cellular responses to skin infections in an experimental animal model were explored. Total leukocyte counts varied after group A streptococcal infections, but a depression was commonly seen after M type 12 impetigo. Staphylococcus aureus infections resulted in moderate leukocytosis. A marked neutrophilia was universal with streptococcal or staphylococcal disease. A positive nitroblue tetrazolium (NBT) response appeared 24 hr after infection, reached a peak in 48 hr, and then declined. This occurred in the absence of extensive cellulitis or bacteremia. An increase in the percentage and absolute number of NBT-positive neutrophils occurred. M type 57 streptococcus produced a more strongly positive NBT test than did M type 12. Cell-free filtrates of a broth culture of M type 57 streptococcus produced NBT responses in hamsters comparable to the responses seen after injection of live organisms. These studies indicate the usefulness of this animal model to study various parameters of the NBT test. PMID:4117885

  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. Ecological Resilience and Resistance in the Hyper Diverse Forests on the Eastern Andean Flank (Mera, Ecuador)

    Science.gov (United States)

    Keen, H. F.; Gosling, W. D.; Montoya, E.; Sherlock, S.; Mothes, P. A.

    2014-12-01

    Today the Neotropics contain some of the world's most biodiverse and threatened ecosystems. Sediments obtained from two radiocarbon infinite (>48,000 years) stratigraphic sections on the eastern Andean flank, provide new insight into the relationship between biodiversity and disturbance during the Pleistocene (~200,000 years). Pollen analysis of modern and fossil material indicates that hyper diverse forest vegetation has been a feature of the Andean flank landscape for 100,000 years (pollen richness: modern = 44, fossil = 48). Correlation of past vegetation with disturbance events (volcanic and fluvial) indicates the response of hyper-diverse forest to past landscape scale change. Pollen records from near Mera (01°27 S, 78°06 W; 1117 m asl) indicate two major changes in the pollen assemblage, with forest communities dominated by: i) Hedyosmum-Alnus-Ilex, and ii) Combretaceae-Melastomataceae-Myrtaceae. These two pollen assemblages most closely resemble modern vegetation cloud forest (2500-3400m asl) and lower montane rain forest (700-2499 m asl) respectively. Sedimentary evidence suggests that at least 21 volcanic events and three changes in the local fluvial regime perturbed the regional landscape during the period of deposition. However, there is no evidence for volcanic or fluvial disturbance events causing a persistent change in vegetation community. Volcanic events (tephra deposits) are associated with increased fire (charcoal particles), and changes in vegetation (pollen grains); however, within ~50cm of sediment accumulation above each tephra, pollen assemblages revert to pre-deposition compositions. Increased fluvial influence (gravel deposits) is associated with elevated input of pollen from taxa today found at higher elevations (Podocarpus-Celtis). The input of high elevation taxa concomitant with fluvial deposits is most likely indicative of an increase in long-distance transport of pollen along water courses originating in the Andes. Our data indicate

  3. Integration of Expressed Sequence Tag Data Flanking Predicted RNA Secondary Structures Facilitates Novel Non-Coding RNA Discovery

    Science.gov (United States)

    Krzyzanowski, Paul M.; Price, Feodor D.; Muro, Enrique M.; Rudnicki, Michael A.; Andrade-Navarro, Miguel A.

    2011-01-01

    Many computational methods have been used to predict novel non-coding RNAs (ncRNAs), but none, to our knowledge, have explicitly investigated the impact of integrating existing cDNA-based Expressed Sequence Tag (EST) data that flank structural RNA predictions. To determine whether flanking EST data can assist in microRNA (miRNA) prediction, we identified genomic sites encoding putative miRNAs by combining functional RNA predictions with flanking ESTs data in a model consistent with miRNAs undergoing cleavage during maturation. In both human and mouse genomes, we observed that the inclusion of flanking ESTs adjacent to and not overlapping predicted miRNAs significantly improved the performance of various methods of miRNA prediction, including direct high-throughput sequencing of small RNA libraries. We analyzed the expression of hundreds of miRNAs predicted to be expressed during myogenic differentiation using a customized microarray and identified several known and predicted myogenic miRNA hairpins. Our results indicate that integrating ESTs flanking structural RNA predictions improves the quality of cleaved miRNA predictions and suggest that this strategy can be used to predict other non-coding RNAs undergoing cleavage during maturation. PMID:21698286

  4. Expression of AMPK, SIRT1, and ACC Differs between Winter- and Summer-Acclimatized Djungarian Hamsters.

    Science.gov (United States)

    Kinnunen, Sanni M E; Mänttäri, Satu K; Saarela, Seppo Y O

    The wintering strategy of the Djungarian hamster (Phodopus sungorus) includes a naturally occurring decrease in food intake and body mass. Our aim was to investigate the conceivable role of the metabolic regulators, AMP-activated protein kinase (AMPK) and sirtuin 1 (SIRT1), in the seasonal adaptation of the Djungarian hamster. In addition, a rate-limiting enzyme in fatty acid synthesis and oxidation, acetyl CoA carboxylase (ACC), was studied. Relative protein expressions and phosphorylated forms (pAMPK and pACC) were determined by Western blot from subcutaneous white adipose tissues (sWAT), abdominal white adipose tissues (aWAT), interscapular brown adipose tissues (iBAT), skeletal muscle, and hypothalamus of winter- and summer-acclimatized hamsters. The winter group had higher AMPK expression in sWAT, aWAT, and iBAT, but the relative amount of phosphorylated protein (pAMPK/AMPK ratio) was lower in these tissues. Furthermore, ACC expression was higher in sWAT and iBAT of the winter animals. pACC (inactive form) levels were higher in all adipose tissues, yet a lower pACC/ACC ratio was detected in iBAT of the winter hamsters. Muscle AMPK expression was lower but pAMPK/AMPK ratio higher in the winter group. SIRT1 expression was higher in muscle and all adipose tissues of the winter hamsters. Hypothalamic protein expressions did not differ between the groups. Higher expressions of AMPK, ACC, and SIRT1 in WAT and iBAT of the winter hamsters suggest a role in the regulation of lipid reserves and increased thermogenic capacity characteristic to the winter-adapted Djungarian hamsters.

  5. Apoptosis and molecular pathways in the seminiferous epithelium of aged and photoinhibited Syrian hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Morales, Eva; Ferrer, Concepcion; Zuasti, Adelina; Garcia-Borron, Jose C; Canteras, Manuel; Pastor, Luis M

    2007-01-01

    Aging and short photoperiod exposure induce germ cell apoptosis in the Syrian hamster; however, the specific germ cells affected and the molecular pathways triggered have not been elucidated. We analyzed germ cell apoptosis and the expression of the Fas/Fas-L system, Bcl-2 family, and p53 in aged and photoinhibited hamsters and compared with those young maintained in natural photoperiod. Aging increased apoptosis in spermatogonia and spermatocytes, but in photoinhibited hamster testes only an increase in apoptotic spermatocytes was observed. Apoptosis was higher in aged hamsters in stages I-IV, V-VI and VII-VIII. Aging increased apoptosis of spermatogonia in stages I-IV and V-VI. Apoptotic pachytene spermatocytes were significantly higher in stages I-IV, V-VI, and VII-VIII in aging. Apoptotic preleptotene and pachytene spermatocytes were higher in aging, but no differences were observed in leptotene-zygotene. Fas-L was expressed by Sertoli cells, of young, aged, and photoinhibited hamsters. Bcl-x(L) was strongly expressed in germ cells on young hamsters and slightly in aging and after short photoperiod exposure. Spermatocytes of photoinhibited hamsters were intensively stained with Fas, Bax, Bcl-xs/L, and p53. In conclusion, aging increases apoptosis in spermatogonia and spermatocytes, depending on the stage of the seminiferous epithelium cycle, whereas after a short photoperiod exposure only an increase in apoptotic spermatocytes is observed. The results suggest that Fas, Bcl-x(L), Bax, and p53 participate in germ cell apoptosis induction after short photoperiod exposure, whereas only Bcl-x(L) is involved in aging.

  6. 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.

  7. Simulation method for interference fringe patterns in measuring gear tooth flanks by laser interferometry.

    Science.gov (United States)

    Fang, Suping; Wang, Leijie; Komori, Masaharu; Kubo, Aizoh

    2010-11-20

    We present a ray-tracing-based method for simulation of interference fringe patterns (IFPs) for measuring gear tooth flanks with a two-path interferometer. This simulation method involves two steps. In the first step, the profile of an IFP is achieved by means of ray tracing within the object path of the interferometer. In the second step, the profile of an IFP is filled with interference fringes, according to a set of functions from an optical path length to a fringe gray level. To examine the correctness of this simulation method, simulations are performed for two spur involute gears, and the simulated IFPs are verified by experiments using the actual two-path interferometer built on an optical platform.

  8. The sequence of the human phosducin gene (PDC) and its 5[prime]-flanking region

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Toshiaki; Kikuchi, Takanobu; Shinohara, Toshimichi (National Eye Institute, Bethesda, MD (United States))

    1994-01-15

    Phosducin, a principal protein of retinal photoreceptor cells, modulates the phototransduction cascade by interacting with transducin. Recently, it has been reported that phosducin is a protein virtually identical to the G-protein inhibitor protein (GIP) in brain. Here, the authors have sequenced the complete human gene (PDC) and 2215 bp of its 5[prime]-flanking region. The gene is 18 kb in length and has four exons and three introns. The splicing sites for donor and acceptor are in good agreement with the GT/AG rule. Comparative studies of human and mouse phosducin revealed highly homologous sequences. Both the human phosducin gene and a mutant gene locus for Usher syndrome type II have been assigned to chromosome 1q25-q32. The association of this gene with a human disease locus suggests that phosducin may be a potential candidate gene for this disorder. 24 refs., 3 figs.

  9. Simultaneous Double Star and Cluster FTEs observations on the dawnside flank of the magnetosphere

    Directory of Open Access Journals (Sweden)

    A. Marchaudon

    2005-11-01

    Full Text Available We present Cluster and Double Star-1 (TC-1 observations from a close magnetic conjunction on 8 May 2004. The five spacecraft were on the dawnside flank of the magnetosphere, with TC-1 located near the equatorial plane and Cluster at higher geographic latitudes in the Southern Hemisphere. TC-1, at its apogee, skimmed the magnetopause for almost 8h (between 08:00-16:00 UT. Flux Transfer Events (FTEs, moving southward/tailward from the reconnection site, were observed by TC-1 throughout almost all of the period. Cluster, travelling on a mainly dawn-dusk trajectory, crossed the magnetopause at around 10:30 UT in the same Magnetic Local Time (MLT sector as TC-1 and remained close to the magnetopause boundary layer in the Southern Hemisphere. The four Cluster spacecraft observed FTEs for a period of 6.5h between 07:30 and 14:00 UT.

    The very clear signatures and the finite transverse sizes of the FTEs observed by TC-1 and Cluster imply that, during this event, sporadic reconnection occurred. From the properties of these FTEs, the reconnection site was located northward of both TC-1 and Cluster on the dawn flank of the magnetosphere. Reconnection occurred between draped magnetosheath and closed magnetospheric field lines. Despite variable interplanetary magnetic field (IMF conditions and IMF-Bz turnings, the IMF clock angle remained greater than 70° and the location site appeared to remain relatively stable in position during the whole period. This result is in agreement with previous studies which reported that the dayside reconnection remained active for an IMF clock angle greater than 70°. The simultaneous observation of FTEs at both Cluster and TC-1, separated by 2h in MLT, implies that the reconnection site on the magnetopause must have been extended over several hours in MLT.

  10. Simultaneous Double Star and Cluster FTEs observations on the dawnside flank of the magnetosphere

    Directory of Open Access Journals (Sweden)

    A. Marchaudon

    2005-11-01

    Full Text Available We present Cluster and Double Star-1 (TC-1 observations from a close magnetic conjunction on 8 May 2004. The five spacecraft were on the dawnside flank of the magnetosphere, with TC-1 located near the equatorial plane and Cluster at higher geographic latitudes in the Southern Hemisphere. TC-1, at its apogee, skimmed the magnetopause for almost 8h (between 08:00-16:00 UT. Flux Transfer Events (FTEs, moving southward/tailward from the reconnection site, were observed by TC-1 throughout almost all of the period. Cluster, travelling on a mainly dawn-dusk trajectory, crossed the magnetopause at around 10:30 UT in the same Magnetic Local Time (MLT sector as TC-1 and remained close to the magnetopause boundary layer in the Southern Hemisphere. The four Cluster spacecraft observed FTEs for a period of 6.5h between 07:30 and 14:00 UT. The very clear signatures and the finite transverse sizes of the FTEs observed by TC-1 and Cluster imply that, during this event, sporadic reconnection occurred. From the properties of these FTEs, the reconnection site was located northward of both TC-1 and Cluster on the dawn flank of the magnetosphere. Reconnection occurred between draped magnetosheath and closed magnetospheric field lines. Despite variable interplanetary magnetic field (IMF conditions and IMF-Bz turnings, the IMF clock angle remained greater than 70° and the location site appeared to remain relatively stable in position during the whole period. This result is in agreement with previous studies which reported that the dayside reconnection remained active for an IMF clock angle greater than 70°. The simultaneous observation of FTEs at both Cluster and TC-1, separated by 2h in MLT, implies that the reconnection site on the magnetopause must have been extended over several hours in MLT.

  11. Whale phylogeny and rapid radiation events revealed using novel retroposed elements and their flanking sequences

    Directory of Open Access Journals (Sweden)

    Zhou Kaiya

    2011-10-01

    Full Text Available Abstract Background A diversity of hypotheses have been proposed based on both morphological and molecular data to reveal phylogenetic relationships within the order Cetacea (dolphins, porpoises, and whales, and great progress has been made in the past two decades. However, there is still some controversy concerning relationships among certain cetacean taxa such as river dolphins and delphinoid species, which needs to be further addressed with more markers in an effort to address unresolved portions of the phylogeny. Results An analysis of additional SINE insertions and SINE-flanking sequences supported the monophyly of the order Cetacea as well as Odontocete, Delphinoidea (Delphinidae + Phocoenidae + Mondontidae, and Delphinidae. A sister relationship between Delphinidae and Phocoenidae + Mondontidae was supported, and members of classical river dolphins and the genera Tursiops and Stenella were found to be paraphyletic. Estimates of divergence times revealed rapid divergences of basal Odontocete lineages in the Oligocene and Early Miocene, and a recent rapid diversification of Delphinidae in the Middle-Late Miocene and Pliocene within a narrow time frame. Conclusions Several novel SINEs were found to differentiate Delphinidae from the other two families (Monodontidae and Phocoenidae, whereas the sister grouping of the latter two families with exclusion of Delphinidae was further revealed using the SINE-flanking sequences. Interestingly, some anomalous PCR amplification patterns of SINE insertions were detected, which can be explained as the result of potential ancestral SINE polymorphisms and incomplete lineage sorting. Although a few loci were potentially anomalous, this study demonstrated that the SINE-based approach is a powerful tool in phylogenetic studies. Identifying additional SINE elements that resolve the relationships in the superfamily Delphinoidea and family Delphinidae will be important steps forward in completely resolving

  12. Late Pleistocene flank collapse of Zempoala volcano (Central Mexico) and the role of fault reactivation

    Science.gov (United States)

    Arce, José Luis; Macías, Rodolfo; García Palomo, Armando; Capra, Lucia; Macías, José Luis; Layer, Paul; Rueda, Hernando

    2008-11-01

    Zempoala is an extinct Pleistocene (˜ 0.7-0.8 Ma) stratovolcano that together with La Corona volcano (˜ 0.9 Ma) forms the southern end of the Sierra de las Cruces volcanic range, Central Mexico. The volcano consists of andesitic and dacitic lava flows and domes, as well as pyroclastic and epiclastic sequences, and has had a complex history with several flank collapses. One of these collapses occurred during the late Pleistocene on the S-SE flank of the volcano and produced the Zempoala debris avalanche deposit. This collapse could have been triggered by the reactivation of two normal fault systems (E-W and NE-SW), although magmatic activity cannot be absolutely excluded. The debris avalanche traveled 60 km to the south, covers an area of 600 km 2 and has a total volume of 6 km 3, with a calculated Heim coefficient (H/L) of 0.03. Based on the textural characteristics of the deposit we recognized three zones: proximal, axial, and lateral distal zone. The proximal zone consists of debris avalanche blocks that develop a hummocky topography; the axial zone corresponds with the main debris avalanche deposit made of large clasts set in a sandy matrix, which transformed to a debris flow in the lateral distal portion. The deposit is heterolithologic in composition, with dacitic and andesitic fragments from the old edifice that decrease in volume as bulking of exotic clasts from the substratum increase. Several cities (Cuernavaca, Jojutla de Juárez, Alpuyeca) with associated industrial, agricultural, and tourism activities have been built on the deposit, which pose in evidence the possible impact in case of a new event with such characteristics, since the area is still tectonically active.

  13. Flank instability of Stromboli volcano detected by long-term GB-InSAR monitoring

    Science.gov (United States)

    Intrieri, Emanuele; Di Traglia, Federico; Del Ventisette, Chiara; Gigli, Giovanni; Mugnai, Francesco; Luzi, Guido; Casagli, Nicola

    2013-04-01

    Stromboli is a volcanic island in Southern Italy characterized by explosions of variable energy every 10-20 minutes and periodically interrupted by more energetic blasts emitting large volumes of material. The pressurization of volatile-poor, high-porphyritic magma column that is gas-recharged by the deep-seated, volatile-rich, low-porphyritic magma precedes such events and produces deformations on the NW flank of the volcano, called Sciara del Fuoco. By integrating geomorphological observations with long-term deformations measured by a ground-based interferometric radar since December 2007, we managed to map two landslides whose movements are strongly related with volcanic activity. Deformation patterns obtained through a novel long-term analysis of GB-InSAR data, usually exploited for real time monitoring and early warning of slope with high risk, permitted us to hypothesize the type of movement and depth for both landslides. During the last 5 years their deformation velocity reached a maximum of more than 2 mm/day. Furthermore their position allowed us to affirm that the effusive vent formed in 2007 at 400 m a.s.l., was the result of the deflection of a feeder dike operated by landslide fractures, thus showing the important role of geomorphological discontinuities in volcanic environments. The study of slope instability of the Sciara del Fuoco is also relevant with reference to tsunami risk, especially considering that mass movements similar to those detected may take place also in other portions of the volcano flank not visible by the current installation.

  14. Whale phylogeny and rapid radiation events revealed using novel retroposed elements and their flanking sequences.

    Science.gov (United States)

    Chen, Zhuo; Xu, Shixia; Zhou, Kaiya; Yang, Guang

    2011-10-27

    A diversity of hypotheses have been proposed based on both morphological and molecular data to reveal phylogenetic relationships within the order Cetacea (dolphins, porpoises, and whales), and great progress has been made in the past two decades. However, there is still some controversy concerning relationships among certain cetacean taxa such as river dolphins and delphinoid species, which needs to be further addressed with more markers in an effort to address unresolved portions of the phylogeny. An analysis of additional SINE insertions and SINE-flanking sequences supported the monophyly of the order Cetacea as well as Odontocete, Delphinoidea (Delphinidae + Phocoenidae + Mondontidae), and Delphinidae. A sister relationship between Delphinidae and Phocoenidae + Mondontidae was supported, and members of classical river dolphins and the genera Tursiops and Stenella were found to be paraphyletic. Estimates of divergence times revealed rapid divergences of basal Odontocete lineages in the Oligocene and Early Miocene, and a recent rapid diversification of Delphinidae in the Middle-Late Miocene and Pliocene within a narrow time frame. Several novel SINEs were found to differentiate Delphinidae from the other two families (Monodontidae and Phocoenidae), whereas the sister grouping of the latter two families with exclusion of Delphinidae was further revealed using the SINE-flanking sequences. Interestingly, some anomalous PCR amplification patterns of SINE insertions were detected, which can be explained as the result of potential ancestral SINE polymorphisms and incomplete lineage sorting. Although a few loci were potentially anomalous, this study demonstrated that the SINE-based approach is a powerful tool in phylogenetic studies. Identifying additional SINE elements that resolve the relationships in the superfamily Delphinoidea and family Delphinidae will be important steps forward in completely resolving cetacean phylogenetic relationships in the future.

  15. 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

  16. Entamoeba histolytica and E. dispar trophozoites in the liver of hamsters: in vivo binding of antibodies and complement

    Directory of Open Access Journals (Sweden)

    Gomes Maria A

    2010-03-01

    Full Text Available Abstract Background Human amoebiasis is caused by the parasitic protozoan Entamoeba histolytica that lives in the large intestine of hosts, where can produce asymptomatic colonization until severe invasive infections with blood diarrhea and spreading to other organs. The amoebic abscesses in liver are the most frequent form of amoebiasis outside intestine and still there are doubts about the pathogenic mechanisms involved in their formation. In this study we evaluated the in situ binding of antibodies, C3 and C9 complement components on trophozoites, in livers of hamsters infected with E. histolytica or E. dispar. These parameters were correlated with the extension of the hepatic lesions observed in these animals and with trophozoites survivor. Methods Hamsters were inoculated intra-hepatically with 100,000 trophozoites of E. histolytica or E. dispar strain and necropsied 12, 24, 48, 72, 144 and 192 h after inoculation. Antibodies, C3 and C9 binding to trophozoites were detected by immunohistochemistry. The estimation of the necrosis area and the number of labeled trophozoites was performed using digital morphometry analysis. Results In the liver sections of animals inoculated with the amoebas, the binding of antibodies to E. histolytica trophozoites was significantly lower than to E. dispar trophozoites. Trophozoites of E. dispar were also more frequently vacuolated and high labeled cellular debris observed in the lesions. Positive diffuse reaction to C3 complement component was more intense in livers of animals inoculated with E. histolytica after 24 and 72 h of infection. C3(+ and C9(+ trophozoites were detected in the vascular lumen, granulomas and inside and in the border of necrotic areas of both infected group animals. C3(+ and C9(+ trophozoite debris immunostaining was higher in livers of E. dispar than in livers of E. histolytica. A positive correlation between necrotic areas and number of C9(+ trophozoites was observed in animals

  17. [Decorative forms of hamsters Phodopus (Mammalia, Cricetinae): an analysis of genetic lines distribution and peculiarities of hair changes].

    Science.gov (United States)

    Feoktistova, N Iu; Chernova, O F; Meshcherskiĭ, I G

    2012-01-01

    Three species of dwarf hamsters (genus Phodopus, family Cricetidae) inhabit some regions of Russia, Kazakhstan, Mongolia, and China, each having quite extensive range. In recent decades, the dwarf hamsters became widely spread all over the world, initially as laboratory animals and later as popular pets. By now, there is lot of decorative breed lines and colored forms of these animals. Comparison of mtDNA nucleotide sequences of dwarf hamsters acquired in pet shops of some countries in Europe, South-East Asia and North America with distribution of mtDNA haplotypes within natural ranges showed the limitation of decorative line founders' points of origin by one region for each of the species. All haplotypes found in decorative Dzungarian hamsters (Ph. sungorus) purchased ounside Russia coincide with or are significantly close to haplotypes spread in the southern part of West Siberia (Russia) and adjacent regions of Kazakhstan; haplotypes of decorative Campbell's hamster (Ph. campbelli) belong to haplogroup of this species natural populations inhabiting South Tyva (Russia); and all studied decorative Desert hamsters (Ph. roborovskii) had one hapotype specific for South-Eastern Kazakhstan. The review of the history of researches on dwarf hamsters biology allows to determine delivery of hamsters from mentioned regions to scientific laboratories and zoos by certain expeditions and/or researchers. Unlike hamsters with natural hair color, the colored hamsters have no normal hair. Their hair is dull and straggly. The hair differentiation (presence of different hair types and their size characteristics) gets broken and results in deformation, bending, and splitting of the shaft, cracks in cuticle, change of configuration and location of medulla, uneven development of cortex. It is assumed that these destructive changes are associated with genetic characteristics of these hamsters' colored forms.

  18. 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.

  19. An experimental study of flank wear in the end milling of AISI 316 stainless steel with coated carbide inserts

    Science.gov (United States)

    Odedeyi, P. B.; Abou-El-Hossein, K.; Liman, M.

    2017-05-01

    Stainless steel 316 is a difficult-to-machine iron-based alloys that contain minimum of about 12% of chromium commonly used in marine and aerospace industry. This paper presents an experimental study of the tool wear propagation variations in the end milling of stainless steel 316 with coated carbide inserts. The milling tests were conducted at three different cutting speeds while feed rate and depth of cut were at (0.02, 0.06 and 01) mm/rev and (1, 2 and 3) mm, respectively. The cutting tool used was TiAlN-PVD-multi-layered coated carbides. The effects of cutting speed, cutting tool coating top layer and workpiece material were investigated on the tool life. The results showed that cutting speed significantly affected the machined flank wears values. With increasing cutting speed, the flank wear values decreased. The experimental results showed that significant flank wear was the major and predominant failure mode affecting the tool life.

  20. Laser clad NiCrBSi alloy wear-resistance coating with RE addition on heavy duty spur gear flank

    Science.gov (United States)

    Zhao, N.; Tao, L.; Guo, H.; Zhang, M. Q.

    2017-10-01

    In this research the wear-resistance composite coating successfully produced on heavy duty gear work surface by laser was reported. The coating containing 99 wt.% NiCrBSi alloy and 1 wt.% RE (rare earth element) oxidation powder. The RE addition coupled with laser operating parameters optimization caused elimination of both cracks and pores meanwhile further enhanced comprehensive properties of the laser layer. The coating microhardness, microstructure, phase construction and wear behaviors were tested by hardness tester, SEM equipped with EDS, XRD and tribometer, respectively. The results reflected the fact that the RE addition enhanced the coating ability of wear resistance and laser clad layer properly bonded with the gear flank. The wear volume loss rate of coating was half of that of the gear flank metal the COF curve of coating kept bellow that of the gear flank steel.

  1. Organic richness and organic matter quality studies of source rocks ...

    African Journals Online (AJOL)

    The hydrocarbon potential of the Upper Cretaceous units (Maastrichtian Mamu Formation) exposed at Imiegba and environs of the Benin Flank, Western Anambra Basin was assessed by Total Organic Carbon (TOC) and Rock-Eval Pyrolysis Analyses. The investigated sections of the Mamu Formation consist of dark grey to ...

  2. 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.

  3. Prenatal development of the eye in the golden hamster.

    Science.gov (United States)

    Jackson, C G

    1976-07-01

    Prenatal development of the eye in golden hamsters is described at the light microscopic level as twelve periods based on salient morphological features. Period one includes shallow and deepened optic sulci in the cephalic neural plate and closing prosencephalon. Period two shows V-shaped prosencephalic evaginations, and Period three, bulbous vesicles. Contact of the retinal disc and lens placode at Period four precedes presumptive retinal invagination and lens pit formation during Period five. During Period six an open lens vesicle, precociously expanded dorsal and lateral optic cup regions and widespread optic fissure margins are evident. A spherical lens lumen, deepened optic cup and narrow optic fissure characterize Period seven. At Period eight posterior lens fibers are elongated, the optic cup is expanded ventrally, and optic fissure margins are juxtaposed or fusing. By Period nine the lens lumen is nearly or completely occluded, the optic fissure is essentially fused and axonal fibers are exiting from the globe. During Period ten corneal components are associated, axonal processes extend to the diencephalon, and lid folds cover more than half of the cornea. By Period eleven eyelids are fused. Anteriorly the pigmented epithelium is thickened and densely pigmented; outer and inner neuroblastic retinal layers are clearly distinguishable. Period twelve is marked by conspicuous anterior folds of pigmented epithelium; a relatively anuclear zone virtually separates outer and inner neuroblastic layers of the retina.

  4. Stochastic aspects of leukocyte transit in hamster cheek pouch arterioles.

    Science.gov (United States)

    Mayrovitz, R A; Mayrovitz, H N

    1992-02-01

    To clarify the dynamics of leukocyte delivery to the capillary network we measured leukocyte velocity (Vwbc), leukocyte flux and the intra-arrival times between successive leukocytes in terminal arterioles of the cheekpouch of eight hamsters. The sequences, generated electronically when fluorescent leukocytes passed a fixed point in the arteriole, were analyzed as stochastic point processes. Results showed that six sequences were stationary, and two with a linear trend in Vwbc, were not. Tests performed on the stationary sequences indicated conformity to a renewal process in all cases. Analysis of the distributional and sequential properties of the sequences indicated a good fit to a Poisson process. Overall these results show that leukocyte delivery to the capillary network can be characterized as a Poisson process if Vwbc remains relatively constant, if not, a non-homogeneous Poisson process is a more suitable model, with Vwbc being the explanatory variable. The demonstration of the applicability of these models may lead to a more complete understanding of both the physiological and patho-physiological dynamics of leukocytes within the microvasculature.

  5. 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.

  6. [Cytotoxicity studies on T-3262 in cultured Chinese hamster cells].

    Science.gov (United States)

    Yoneda, T; Nakamura, S; Nojima, Y; Nishio, Y

    1989-04-01

    T-3262 is an antibacterial drug which belongs to the group of pyridonecarboxylic acids. In this study, we investigated cytotoxicity of T-3262 for inhibition of cell growth and effects on viability of, and morphological changes in cultured Chinese hamster cells (V79 cells). The following results were obtained. 1. The 50% inhibition dose of T-3262 for cell growth (ID50, cultured for 48 hours) was 12 micrograms/ml, showing that the inhibitory effect of T-3262 on the cell growth was stronger than that of enoxacin (ENX: ID50 44 micrograms/ml), norfloxacin (NFLX: ID50 105 micrograms/ml) or ofloxacin (OFLX: ID50 145 micrograms/ml). 2. The number of cells increased and dead cells were scarcely seen at the highest concentration tested in culture medium (40 micrograms/ml of T-3262 for 48 hours). At this concentration, degeneration of cytoplasm (atrophy and round shape) and decrease of mitotic cells were observed. These morphological changes were similar to those of the cells treated 400 micrograms/ml of NFLX or OFLX for 48 hours. 3. After the removal of T-3262 from culture medium, the cells began to grow actively and recovered from the morphological changes. The similar phenomenon was observed with ENX treated cells but not with fluorouracil or mitomycin C treated cells.

  7. Development and characterization of intron-flanking EST-PCR markers in rubber tree (Hevea brasiliensis Muell. Arg.).

    Science.gov (United States)

    Li, Dejun; Xia, Zhihui; Deng, Zhi; Liu, Xianghong; Dong, Junmei; Feng, Fuying

    2012-06-01

    With a long-term goal of constructing a linkage map enriched with gene-specific markers in rubber tree (Hevea brasiliensis Muell. Arg.), we utilized rubber tree ESTs associated with tapping panel dryness (TPD) to develop intron-flanking PCR markers. After downloading and assembling the rubber tree ESTs associated with TPD, we predicted the exon/exon junction sites (E/E) by aligning rubber tree transcripts with the genomic sequences of castor bean (Ricinus communis L.). Based on the predicted E/E, the primers flanking intron(s) and no intron were designed. Compared with the markers designed by conventional method, the PCR success rate of the markers designed with the predicted E/E increased 28-30%, whereas the polymorphism rate of intron-flanking EST-PCR markers was approximately 3.43-fold increase. Therefore, the intron-flanking marker was more polymorphism-generating efficient than the markers designed by conventional methods. In addition, analyzing the polymorphic information content (PIC) among Hevea germplasm showed that the polymorphism of wild rubber tree accessions was higher than one of cultivated rubber tree clones and Hevea species. This study enriches the categories and numbers of molecular markers in rubber tree, and the markers developed in this research will have a wide application in DNA fingerprinting, marker-assisted selection and genetic mapping in rubber tree. This research also indicates that it is possible to develop intron-flanking EST-PCR markers of rubber tree with castor bean genome as reference sequences, which provides new insights into developing intron-flanking EST-PCR markers for rubber tree or other plant species without genomic information.

  8. Effects of short photoperiod on energy intake, thermogenesis, and reproduction in desert hamsters (Phodopus roborovskii).

    Science.gov (United States)

    Zhang, Xueying; Zhao, Zhijun; Vasilieva, Nina; Khrushchova, Anastasia; Wang, Dehua

    2015-03-01

    Desert hamsters (Phodopus roborovskii) are the least known species in the genus Phodopus with respect to ecology and physiology, and deserve scientific attention, particularly because of their small body size. Here, the responses of energy metabolism and reproductive function to short photoperiods in desert hamsters were investigated. Male and female desert hamsters were acclimated to either long day (LD) (L:D 16:8 h) or short day (SD) photoperiods (L:D 8:16 h) for three months, and then the females were transferred back to an LD photoperiod for a further five months, while at the end of the SD acclimation the males were killed and measurements were taken for serum leptin as well as molecular markers for thermogenesis. We found that like the other two species from the genus Phodopus, the desert hamsters under SD decreased body mass, increased adaptive thermogenesis as indicated by elevated mitochondrial protein content and uncoupling protein-1 content in brown adipose tissue, and suppressed reproduction compared to those under LD. However, different from the other two species, desert hamsters did not show any differences in energy intake or serum leptin concentration between LD and SD. These data suggest that different species from the same genus respond in different ways to the environmental signals, and the desert adapted species are not as sensitive to change in photoperiod as the other two species. © 2014 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  9. 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.

  10. 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...

  11. 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.

  12. Liver function tests during amoebic liver abscess formation in indomethacin-treated hamsters.

    Science.gov (United States)

    Sánchez-Ramírez, B; Mata-González, S; Valdez, A; Ramos-Martínez, E; Talamás-Rohana, P

    2001-08-01

    Establishment of Entamoeba histolytica infection is facilitated through macrophage effector disruption by a prostaglandin E2 (PGE2)-mediated mechanism. Infection severity may be measured by weight of abscess formed. Indomethacin (Indo) treatment of infected hamsters reduced abscess weight by 30% at 7 days post-infection presumably by inhibition of PGE2. To explain reductions in abscess development by Indo treatment, we determined liver functionality in Indo-treated or untreated animals, either healthy or infected. Determinations of serum glutamic oxaloacetic (SGOT) and glutamic pyruvic (SGPT) transaminases, serum alkaline phosphatase (SAP), total serum protein (TSP), and bilirubinemia were done. SGOT, SGPT, and SAP activities showed a significant increase in their values by 600% at seven days post-infection in infected animals in both conditions; nonstatistical differences were found between animals treated or not. This increase did not correlate with the percentage of damage. Infected nontreated hamsters showed TSP levels 30% below normal group (P hamsters had no significant differences compared to normal values. Infected nontreated animals showed an increase in bilirubin, particularly in indirect bilirubin, whereas infected Indo-treated hamsters showed total bilirubin values lower than normals (P hamsters produces similar abnormalities in liver function as it does in humans, and that the beneficial effect of Indo treatment on amoebic abscess development is not related with an improvement of liver functionality. Copyright 2001 Wiley-Liss, Inc.

  13. 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 (50%) 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.

  14. 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

  15. Protective Effects of Aspirin from Cardiac Hypertrophy and Oxidative Stress in Cardiomyopathic Hamsters

    Directory of Open Access Journals (Sweden)

    Rong Wu

    2012-01-01

    Full Text Available Objective. To evaluate the capacity of chronic ASA therapy to prevent cardiac alterations and increased oxidative stress in cardiomyopathic hamsters. Methods and Results. Male Syrian cardiomyopathic and age-matched inbred control hamsters received ASA orally from the age of 60 days. Animals were sacrificed at the age of 150, 250, and 350 days to evaluate the time course of cardiac hypertrophy and cardiovascular tissue superoxide anion (O2- production. At the age of 150 days, the ventricular weight over body weight ratio, resting heart rate, and cardiovascular O2- production were much higher in cardiomyopathic hamsters than those in control. At the age of 250 days, in addition to the continual deterioration of these parameters with age, the blood pressure started to fall and the signs of heart failure appeared. In these cardiomyopathic hamsters, chronic ASA treatment (a completely prevented elevated O2- production and the NAD(PH oxidase activity, (b significantly slowed down the development of the cardiac hypertrophy and fibrosis. Conclusions. Chronic ASA treatment significantly prevents the deterioration of cardiac function and structure as well as the increased oxidative stress in the cardiomyopathic hamster. Our findings suggest that ASA presents a therapeutic potential to prevent cardiac dysfunction.

  16. Protective effects of aspirin from cardiac hypertrophy and oxidative stress in cardiomyopathic hamsters.

    Science.gov (United States)

    Wu, Rong; Yin, David; Sadekova, Nataliya; Deschepper, Christian F; de Champlain, Jacques; Girouard, Helene

    2012-01-01

    To evaluate the capacity of chronic ASA therapy to prevent cardiac alterations and increased oxidative stress in cardiomyopathic hamsters. Male Syrian cardiomyopathic and age-matched inbred control hamsters received ASA orally from the age of 60 days. Animals were sacrificed at the age of 150, 250, and 350 days to evaluate the time course of cardiac hypertrophy and cardiovascular tissue superoxide anion (O(2)(-)) production. At the age of 150 days, the ventricular weight over body weight ratio, resting heart rate, and cardiovascular O(2)(-) production were much higher in cardiomyopathic hamsters than those in control. At the age of 250 days, in addition to the continual deterioration of these parameters with age, the blood pressure started to fall and the signs of heart failure appeared. In these cardiomyopathic hamsters, chronic ASA treatment (a) completely prevented elevated O(2)(-) production and the NAD(P)H oxidase activity, (b) significantly slowed down the development of the cardiac hypertrophy and fibrosis. Chronic ASA treatment significantly prevents the deterioration of cardiac function and structure as well as the increased oxidative stress in the cardiomyopathic hamster. Our findings suggest that ASA presents a therapeutic potential to prevent cardiac dysfunction.

  17. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1987-05-01

    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 (/sup 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 (/sup 3/H)GDP binding, characteristically observed with rat mitochondria, was not observed with hamster mitochondria, and the increase in (/sup 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/sup -/ 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.

  19. 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.

  20. Association of pancreatic biotinidase activity and intestinal uptake of biotin and biocytin in hamster and rat.

    Science.gov (United States)

    León-Del-Río, A; Velázquez, A; Vizcaíno, G; Robles-Díaz, G; González-Noriega, A

    1990-01-01

    Pancreatic biotinidase activity was higher in hamster than in rat; these results were reversed in plasma. Uptake was studied in everted intestinal rings. Saturation kinetics at 37 degrees C were observed for biotin in hamster and for biocytin in rat, with a Vmax of 1.83 and 1.05 nmol min-1 ml-1 and an apparent Kt of 25.14 and 40.7 microM, respectively. Biotin uptake by hamster intestine was reduced at 4 degrees C and when choline or potassium replaced sodium; it was inhibited by biocytin only at very high concentrations. Biocytin uptake in the rat was small compared to passive diffusion and was not influenced by sodium or temperature; it was not inhibited by biotin. We observed only passive diffusion of biotin in rat and of biocytin in hamster. Our results suggest that protein-bound biotin may be absorbed mainly in its free form in the hamster. In the rat, on the other hand, at least part of the dietary biotin may be absorbed lysine-bound, as biocytin.

  1. 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

  2. Label-free vascular imaging in a spontaneous hamster cheek pouch carcinogen model for pre-cancer detection (Conference Presentation)

    Science.gov (United States)

    Hu, Fangyao; Morhard, Robert; Liu, Heather; Murphy, Helen; Farsiu, Sina; Ramanujam, Nimmi

    2016-03-01

    Inducing angiogenesis is one hallmark of cancer. Tumor induced neovasculature is often characterized as leaky, tortuous and chaotic, unlike a highly organized normal vasculature. Additionally, in the course of carcinogenesis, angiogenesis precedes a visible lesion. Tumor cannot grow beyond 1-2 mm in diameter without inducing angiogenesis. Therefore, capturing the event of angiogenesis may aid early detection of pre-cancer -important for better treatment prognoses in regions that lack the resources to manage invasive cancer. In this study, we imaged the neovascularization in vivo in a spontaneous hamster cheek pouch carcinogen model using a, non-invasive, label-free, high resolution, reflected-light spectral darkfield microscope. Hamsters' cheek pouches were painted with 7,12-Dimethylbenz[a]anthracene (DMBA) to induce pre-cancerous to cancerous changes, or mineral oil as control. High resolution spectral darkfield images were obtained over the course of pre-cancer development and in control cheek pouches. The vasculature was segmented with a multi-scale Gabor filter with an 85% accuracy compared with manually traced masks. Highly tortuous vasculature was observed only in the DMBA treated cheek pouches as early as 6 weeks of treatment. In addition, the highly tortuous vessels could be identified before a visible lesion occurred later during the treatment. The vessel patterns as determined by the tortuosity index were significantly different from that of the control cheek pouch. This preliminary study suggests that high-resolution darkfield microscopy is promising tool for pre-cancer and early cancer detection in low resource settings.

  3. Epiberberine reduces serum cholesterol in diet-induced dyslipidemia Syrian golden hamsters via network pathways involving cholesterol metabolism.

    Science.gov (United States)

    Zou, Zong-Yao; Hu, Yin-Ran; Ma, Hang; Feng, Min; Li, Xue-Gang; Ye, Xiao-Li

    2016-03-05

    This study aimed to evaluate the cholesterol-lowering effect of epiberberine in dyslipidemia Syrian golden hamsters induced by high fat and high cholesterol (HFHC) diet and its regulation mechanism on some key genes involved in cholesterol metabolism. Hamsters were divided into six groups: normal control group (NC), HFHC group, simvastatin (Sim) and three doses of epiberberine group. The body weight, organs weight and serum lipid levels, as well as total cholesterol (TC) and total bile acids (TBA) levels in liver and feces were determined. Furthermore, the antidyslipidemia effect of epiberberine on key genes involved in cholesterol biosynthesis, uptake, conversion and elimination such as 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), low density lipoprotein receptor (LDL receptor), 7-alpha-hydroxylase (CYP7A1) and apical sodium dependent bile acid transporter (ASBT) were investigated. The results showed that epiberberine at high dosage significantly reduced serum TC, low density lipoprotein cholesterol (LDL-c) and TBA levels by 20.2%, 22.3% and 43.8%, respectively, and increased TBA and TC levels in feces. Epiberberine inhibited HMGCR mRNA and protein expressions and slightly reduced the protein level of ASBT, as well as dramatically up-regulated mRNA and protein expressions of CYP7A1 and LDL receptor. These findings suggested that the antidyslipidemia effects of epiberberine can be achieved via inhibiting the synthesis of cholesterol, promoting the uptake and conversion of TC in liver and increasing the excretion of TC and TBA in feces. Thus, epiberberine should be considered as one of the promising natural drugs for the treatment of dyslipidemia. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. 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

  5. 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.

  6. Fish oil induced hyperlipidemia and oxidative stress in BioF1B hamsters is attenuated by elderberry extract.

    Science.gov (United States)

    Dubey, Pratibha; Jayasooriya, Anura P; Cheema, Sukhinder K

    2012-06-01

    We have previously reported fish oil induced hyperlipidemia in BioF1B hamsters compared with Golden Syrian (GS) hamsters. Elderberry (Sambucus nigra L.) extract is abundant in anthocyanins and is believed to exert cardioprotective effects primarily by virtue of its hypolipidemic and antioxidant potential. In the current study, high-fat fish oil feeding increased oxidative stress in BioF1B hamsters compared with GS hamsters; this increase was associated with increased levels of omega-3 polyunsaturated fatty acids in plasma and liver. We then investigated whether cosupplementation with anthocyanin-rich elderberry extract would reverse fish oil induced hyperlipidemia and reduce lipid peroxidation in BioF1B hamsters. Plasma and hepatic lipids decreased significantly when hamsters were fed diets containing elderberry extract along with fish oil. Both plasma and liver thiobarbituric acid reactive substances showed significant reductions upon cosupplementation with elderberry extract in fish oil fed BioF1B hamsters. Our findings demonstrate that cosupplementation with elderberry extract reverses hyperlipidemia and lipid peroxidation observed with dietary fish oil alone in BioF1B hamsters.

  7. Gene discovery in the hamster: a comparative genomics approach for gene annotation by sequencing of hamster testis cDNAs

    Science.gov (United States)

    Oduru, Sreedhar; Campbell, Janee L; Karri, SriTulasi; Hendry, William J; Khan, Shafiq A; Williams, Simon C

    2003-01-01

    Background Complete genome annotation will likely be achieved through a combination of computer-based analysis of available genome sequences combined with direct experimental characterization of expressed regions of individual genomes. We have utilized a comparative genomics approach involving the sequencing of randomly selected hamster testis cDNAs to begin to identify genes not previously annotated on the human, mouse, rat and Fugu (pufferfish) genomes. Results 735 distinct sequences were analyzed for their relatedness to known sequences in public databases. Eight of these sequences were derived from previously unidentified genes and expression of these genes in testis was confirmed by Northern blotting. The genomic locations of each sequence were mapped in human, mouse, rat and pufferfish, where applicable, and the structure of their cognate genes was derived using computer-based predictions, genomic comparisons and analysis of uncharacterized cDNA sequences from human and macaque. Conclusion The use of a comparative genomics approach resulted in the identification of eight cDNAs that correspond to previously uncharacterized genes in the human genome. The proteins encoded by these genes included a new member of the kinesin superfamily, a SET/MYND-domain protein, and six proteins for which no specific function could be predicted. Each gene was expressed primarily in testis, suggesting that they may play roles in the development and/or function of testicular cells. PMID:12783626

  8. Gene discovery in the hamster: a comparative genomics approach for gene annotation by sequencing of hamster testis cDNAs

    Directory of Open Access Journals (Sweden)

    Khan Shafiq A

    2003-06-01

    Full Text Available Abstract Background Complete genome annotation will likely be achieved through a combination of computer-based analysis of available genome sequences combined with direct experimental characterization of expressed regions of individual genomes. We have utilized a comparative genomics approach involving the sequencing of randomly selected hamster testis cDNAs to begin to identify genes not previously annotated on the human, mouse, rat and Fugu (pufferfish genomes. Results 735 distinct sequences were analyzed for their relatedness to known sequences in public databases. Eight of these sequences were derived from previously unidentified genes and expression of these genes in testis was confirmed by Northern blotting. The genomic locations of each sequence were mapped in human, mouse, rat and pufferfish, where applicable, and the structure of their cognate genes was derived using computer-based predictions, genomic comparisons and analysis of uncharacterized cDNA sequences from human and macaque. Conclusion The use of a comparative genomics approach resulted in the identification of eight cDNAs that correspond to previously uncharacterized genes in the human genome. The proteins encoded by these genes included a new member of the kinesin superfamily, a SET/MYND-domain protein, and six proteins for which no specific function could be predicted. Each gene was expressed primarily in testis, suggesting that they may play roles in the development and/or function of testicular cells.

  9. Dietary calcium decreases plasma cholesterol level only in female but not in male hamster fed a high cholesterol diet.

    Science.gov (United States)

    Ma, Ka Ying; Liang, Yin Tong; Chen, Jing Nan; Jiang, Yue; Kwan, Kin Ming; Peng, Cheng; Jiao, Rui; Zuo, Yuan Yuan; Huang, Yu; Chen, Zhen Yu

    2012-08-01

    To investigate the effect of dietary calcium on plasma lipoprotein profile in castrated and ovariectomized hamsters. Male, castrated, female and ovariectomized hamsters (n=36 each group) were randomly divided into three sub-groups (n=12) and fed one of the three diets containing 0, 2, and 8 g calcium per kg diet for a period of six weeks. Changes in plasma lipoprotein profile were monitored at the end of week 0, 3 and 6. Plasma total cholesterol (TC), non-high density lipoprotein cholesterol (non-HDL-C), triacylglycerols (TG) and TC/HDL-C were decreased only in intact female and ovariectomized hamsters. In contrast, three levels of dietary calcium had no effect on lipoprotein profiles in both intact male and castrated hamsters. Beneficial modification of lipoprotein profile by dietary calcium was gender-dependent at least in hamsters. Copyright © 2012 The Editorial Board of Biomedical and Environmental Sciences. Published by Elsevier B.V. All rights reserved.

  10. 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...

  11. 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.

  12. 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...

  13. Entamoeba histolytica sequences and their relationship with experimental liver abscesses in hamsters.

    Science.gov (United States)

    Crisóstomo-Vázquez, María Del Pilar; Jiménez-Cardoso, Enedina; Arroyave-Hernández, Carlos

    2006-01-01

    The purpose of the present paper was to analyse the association between sequences of Entamoeba histolytica and their relationship with the development of hepatic abscesses in hamsters, using a complementary DNA library for E. histolytica. From the sequences obtained, we designed oligonucleotides for amplification by PCR. Trophozoites were isolated from faeces of 11 patients in whom cysts from E. histolytica were identified, and these trophozoites were then subjected to monoaxenic culture. Then 1 x 10(5) trophozoites were inoculated into hamster liver, with three hamsters used for every culture. Sequences were obtained for ubiquitin, lectin surface precursor, replication factor MCM3 and surface antigen. The associations between sequences and hepatic abscesses were: 11/11 for ubiquitin, 9/11 for lectin precursor, 4/11 for replication factor and 1/11 for surface antigen. These results suggest that ubiquitin could be an important protein involved in the mechanism of E. histolytica invasion.

  14. A brief view of known landmarks reorientates path integration in hamsters

    Science.gov (United States)

    Etienne, A. S.; Boulens, V.; Maurer, R.; Rowe, T.; Siegrist, C.

    In darkness, hamsters commute between their nest and a feeding site through path integration only, and therefore show cumulative errors in the return direction to the nest. We examined whether a brief presentation of familiar room cues could reset the path integrator. The hamsters could see the room cues either during, or at the end of, the outward journey to the food place, in a conflict situation where motion cues and visual information were set at variance. In both conditions, the animals used mainly visual information to return home. Thus, hamsters can determine their azimuth, and possibly their location, through a visual fix, and can reset their path integrator through the fix. This allows them to update their position during further locomotion in the dark and thus to compute a correct homing vector with respect to a visually induced reference frame. Taking episodic positional fixes may greatly enhance the functional value of path integration.

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

    Science.gov (United States)

    Kasbi Chadli, Fatima; Nazih, Hassane; Krempf, Michel; Nguyen, Patrick; Ouguerram, Khadija

    2013-01-01

    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 (3)H-cholesterol-labelled hamster primary macrophages. Compared to Control, HF presented significant (phamster 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. An EAV-HP insertion in 5' Flanking region of SLCO1B3 causes blue eggshell in the chicken.

    Directory of Open Access Journals (Sweden)

    Zhepeng Wang

    Full Text Available The genetic determination of eggshell coloration has not been determined in birds. Here we report that the blue eggshell is caused by an EAV-HP insertion that promotes the expression of SLCO1B3 gene in the uterus (shell gland of the oviduct in chicken. In this study, the genetic map location of the blue eggshell gene was refined by linkage analysis in an F(2 chicken population, and four candidate genes within the refined interval were subsequently tested for their expression levels in the shell gland of the uterus from blue-shelled and non-blue-shelled hens. SLCO1B3 gene was found to be the only one expressed in the uterus of blue-shelled hens but not in that of non-blue-shelled hens. Results from a pyrosequencing analysis showed that only the allele of SLCO1B3 from blue-shelled chickens was expressed in the uterus of heterozygous hens (O*LC/O*N. SLCO1B3 gene belongs to the organic anion transporting polypeptide (OATP family; and the OATPs, functioning as membrane transporters, have been reported for the transportation of amphipathic organic compounds, including bile salt in mammals. We subsequently resequenced the whole genomic region of SLCO1B3 and discovered an EAV-HP insertion in the 5' flanking region of SLCO1B3. The EAV-HP insertion was found closely associated with blue eggshell phenotype following complete Mendelian segregation. In situ hybridization also demonstrated that the blue eggshell is associated with ectopic expression of SLCO1B3 in shell glands of uterus. Our finding strongly suggests that the EAV-HP insertion is the causative mutation for the blue eggshell phenotype. The insertion was also found in another Chinese blue-shelled breed and an American blue-shelled breed. In addition, we found that the insertion site in the blue-shelled chickens from Araucana is different from that in Chinese breeds, which implied independent integration events in the blue-shelled chickens from the two continents, providing a parallel evolutionary

  1. Dynamics and timing of paleoglaciation on opposite flanks of the Ikh-Turgen Mountains, Central Asia

    Science.gov (United States)

    Blomdin, Robin; Stroeven, Arjen P.; Harbor, Jonathan M.; Gribenski, Natacha; Caffee, Marc W.; Heyman, Jakob; Rogozhina, Irina; Ivanov, Mikhail N.; Petrakov, Dmitry A.; Walther, Michael; Rudoy, Alexei N.; Zhang, Wei; Alexander, Orkhonselenge; Hättestrand, Clas; Lifton, Nathaniel A.; Jansson, Krister N.

    2017-04-01

    Spanning a northern sector of continental Central Asia, the Altai Mountains contains a rich record of glaciation. Still, there are few studies reconstructing the dynamics and timing of former glaciers in the region. We investigated the glacial history of two paleoglaciers, residing on opposite flanks of the Ikh-Turgen Mountains, straddling the border between Russia and Mongolia, using a combination of remote sensing, terrain analysis, field investigations and 10Be surface exposure dating. On the eastern side (Mongolia) of Ikh-Turgen, mean arithmetic exposure ages from a latero-frontal moraine indicate deglaciation during Marine Isotope Stage (MIS) 3 (45.3±2.7 ka, n=5) and MIS 2 (22.8±3.5 ka, n=4). These age constraints are consistent with other paleoclimate records from the region. Cold and wet conditions during early MIS 2 and MIS 3 likely triggered glacier expansions but the transition to a drier climate resulted in more restricted paleoglacier extents during MIS 2 than during MIS 3. Well-constrained MIS 3 glacier expansions in Central Asia are rare. We therefore speculate whether the climatic and topographic setting of the eastern flank of the Ikh-Turgen Mountains has allowed for a better preservation potential of these moraines, making them more suitable for surface exposure dating than other regions of Central Asia, or whether MIS 3 moraines occur more widespread but await to be robustly dated. Corresponding surface exposure ages, from the western side (Russia) of Ikh-Turgen, indicate a more complex story with large scatter ( 14-53 ka, n=8) making paleoclimate inference and comparison to other proxies difficult. Owing to their proximity, the paleoglaciers of Ikh-Turgen, should have responded similarly to climate forcing, yet they exhibited distinctly different behaviours. We discuss the connection between paleoglacier dynamics and style of moraine deposition and propose that differences in glacier dynamics caused differences in ice-marginal depositional

  2. Cryopreservation and In Vitro culture of Preimplantation Embryos in Djungarian Hamster (Phodopus sungorus).

    Science.gov (United States)

    Brusentsev, E Yu; Abramova, T O; Rozhkova, I N; Igonina, T N; Naprimerov, V A; Feoktistova, N Yu; Amstislavsky, S Ya

    2015-08-01

    Although embryo cryobanking was applied to Syrian golden and to Campbell's hamsters, no attempt has been made at freezing embryos in Djungarian hamsters. Four-cell stage embryos were flushed from the reproductive ducts of pregnant females before noon of the third-day post coitum and frozen in 0.25-ml straws according to standard procedures of slow cooling. A mixture of permeating (ethylene glycol) and non-permeating (sucrose) cryoprotectants was used. The thawing was performed by incubating at RT for 40 s followed by 40 s in a water bath at 30.0°C. Most (66.7%) of the non-frozen four-cell embryos developed up to the morula stage in rat one-cell embryo culture medium (R1ECM). The use of hamster embryo culture medium (HECM) yielded fewer morulas (18.2%) during the same 24-h period of culture. The rate of embryo's surviving the freezing-thawing procedures, as estimated by light microscopy, was 60.7-68.8%. After 24-h culturing in R1ECM, 64.7% of frozen-thawed four-cell embryos developed and all of them reached the morula stage. Supplementation of R1ECM with GM-CSF (2 ng/ml) improved the rate of Djungarian hamster frozen-thawed embryo development: 100% of the four-cell stage embryos developed, 50% of them achieved the morula stage, and 50% developed even further and reached the blastocyst stage within 24 h of culturing. This study reports the world's first successful transfer of frozen-thawed Djungarian hamster embryos yielding term pups. Taken together, the results of this study demonstrate the possibility of applying some key reproductive technologies, that is, embryo freezing/cryopreservation and in vitro culture, to Djungarian hamsters. © 2015 Blackwell Verlag GmbH.

  3. Cross-species transcriptomic approach reveals genes in hamster implantation sites.

    Science.gov (United States)

    Lei, Wei; Herington, Jennifer; Galindo, Cristi L; Ding, Tianbing; Brown, Naoko; Reese, Jeff; Paria, Bibhash C

    2014-12-01

    The mouse model has greatly contributed to understanding molecular mechanisms involved in the regulation of progesterone (P4) plus estrogen (E)-dependent blastocyst implantation process. However, little is known about contributory molecular mechanisms of the P4-only-dependent blastocyst implantation process that occurs in species such as hamsters, guineapigs, rabbits, pigs, rhesus monkeys, and perhaps humans. We used the hamster as a model of P4-only-dependent blastocyst implantation and carried out cross-species microarray (CSM) analyses to reveal differentially expressed genes at the blastocyst implantation site (BIS), in order to advance the understanding of molecular mechanisms of implantation. Upregulation of 112 genes and downregulation of 77 genes at the BIS were identified using a mouse microarray platform, while use of the human microarray revealed 62 up- and 38 down-regulated genes at the BIS. Excitingly, a sizable number of genes (30 up- and 11 down-regulated genes) were identified as a shared pool by both CSMs. Real-time RT-PCR and in situ hybridization validated the expression patterns of several up- and down-regulated genes identified by both CSMs at the hamster and mouse BIS to demonstrate the merit of CSM findings across species, in addition to revealing genes specific to hamsters. Functional annotation analysis found that genes involved in the spliceosome, proteasome, and ubiquination pathways are enriched at the hamster BIS, while genes associated with tight junction, SAPK/JNK signaling, and PPARα/RXRα signalings are repressed at the BIS. Overall, this study provides a pool of genes and evidence of their participation in up- and down-regulated cellular functions/pathways at the hamster BIS. © 2014 Society for Reproduction and Fertility.

  4. Secondhand smoke exposure toxicity accelerates age-related cardiac disease in old hamsters.

    Science.gov (United States)

    Wu, Jia-Ping; Hsieh, Cheng-Hong; Ho, Tsung-Jung; Kuo, Wei-Wen; Yeh, Yu-Lan; Lin, Chien-Chung; Kuo, Chia-Hua; Huang, Chih-Yang

    2014-12-19

    Aging is associated with physiological or pathological left ventricular hypertrophy (LVH) cardiac changes. Secondhand smoke (SHS) exposure is associated with pathological LVH. The action mechanism in cardiac concentric hypertrophy from SHS exposure is understood, but the transition contributed from SHS exposure is not. To determine whether exposure to SHS has an impact on age-induced LVH we examined young and old hamsters that underwent SHS exposure in a chamber for 30 mins. Morphological and histological studies were then conducted using hematoxylin and eosin (H&E) and Masson's trichrome staining. Echocardiographic analysis was used to determine left ventricular wall thickness and function. LVH related protein expression levels were detected by western blot analysis. The results showed that both young and aged hamsters exposed to SHS exhibited increased heart weights and left ventricular weights, left ventricular posterior wall thickness and intraventricular septum systolic and diastolic pressure also increased. However, left ventricular function systolic and diastolic pressure deteriorated. H&E and Masson's trichrome staining results showed LV papillary muscles were ruptured, resulting in lower cardiac function at the myocardial level. LV muscle fiber arrangement was disordered and collagen accumulation occurred. Concentric LVH related protein molecular markers increased only in young hamsters exposed to SHS. However, this declined with hamster age. By contrast, eccentric LVH related proteins increased in aging hamsters exposed the SHS. Pro-inflammatory proteins, IL-6, TNF-α, JAK1, STAT3, and SIRTI expression increased in aging hamsters exposed to SHS. We suggest that SHS exposure induces a pro-inflammatory response that results in concentric transition to aging eccentric LVH.

  5. Diet-induced metabolic hamster model of nonalcoholic fatty liver disease.

    Science.gov (United States)

    Bhathena, Jasmine; Kulamarva, Arun; Martoni, Christopher; Urbanska, Aleksandra Malgorzata; Malhotra, Meenakshi; Paul, Arghya; Prakash, Satya

    2011-01-01

    Obesity, hypercholesterolemia, elevated triglycerides, and type 2 diabetes are major risk factors for metabolic syndrome. Hamsters, unlike rats or mice, respond well to diet-induced obesity, increase body mass and adiposity on group housing, and increase food intake due to social confrontation-induced stress. They have a cardiovascular and hepatic system similar to that of humans, and can thus be a useful model for human pathophysiology. Experiments were planned to develop a diet-induced Bio F(1)B Golden Syrian hamster model of dyslipidemia and associated nonalcoholic fatty liver disease in the metabolic syndrome. Hamsters were fed a normal control diet, a high-fat/high-cholesterol diet, a high-fat/high-cholesterol/methionine-deficient/choline-devoid diet, and a high-fat/high-cholesterol/choline-deficient diet. Serum total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, glucose, atherogenic index, and body weight were quantified biweekly. Fat deposition in the liver was observed and assessed following lipid staining with hematoxylin and eosin and with oil red O. In this study, we established a diet-induced Bio F(1)B Golden Syrian hamster model for studying dyslipidemia and associated nonalcoholic fatty liver disease in the metabolic syndrome. Hyperlipidemia and elevated serum glucose concentrations were induced using this diet. Atherogenic index was elevated, increasing the risk for a cardiovascular event. Histological analysis of liver specimens at the end of four weeks showed increased fat deposition in the liver of animals fed with a high-fat/high cholesterol diet, as compared to animals fed with the control diet. Our study established that hamsters fed with a high-fat/high-cholesterol diet developed fatty liver and mild diabetes. Bio F(1)B hamsters fed with a high-fat/high-cholesterol diet may thus be a good animal model for research on the treatment of diet-induced metabolic syndrome complicated by

  6. Comparative Metabolism of Carbon Tetrachloride in Rats, Mice and Hamsters Using Gas Uptake and PBPK Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Thrall, Karla D.(BATTELLE (PACIFIC NW LAB)); Vucelick, Mark E.(FLUOR HANFORD, INC); Gies, Richard A.(BATTELLE (PACIFIC NW LAB)); Zangar, Richard C.(BATTELLE (PACIFIC NW LAB)); Weitz, Karl K.(BATTELLE (PACIFIC NW LAB)); Poet, Torka S.(BATTELLE (PACIFIC NW LAB)); Springer, David L.(BATTELLE (PACIFIC NW LAB)); Grant, Donna M.(BATTELLE (PACIFIC NW LAB)); Benson, Janet M.(Inhalation Toxicology Research Institute)

    2000-08-25

    No study has comprehensively compared the rate of metabolism of carbon tetrachloride (CCl4) across species. Therefore, the in vivo metabolism of CCl4 was evaluated using groups of male animals (F344 rats, B6C3F1 mice, and Syrian hamsters) exposed to 40-1800 ppm CCl4 in a closed, recirculating gas-uptake system. For each species, an optimal fit of the family of uptake curves was obtained by adjusting Michaelis-Menten metabolic constants Km (affinity) and Vmax (capacity) using a physiologically based pharmacokinetic (PBPK) model. The results show that the mouse has a slightly higher capacity and lower affinity for metabolizing CCl4 compared to the rat, while the hamster has a higher capacity and lower affinity than either rat or mouse. A comparison of the Vmax to Km ratio, normalized for mg of liver protein (L/hr/mg) across species indicates that hamsters metabolize more CCl4 than either rats or mice, and should be more susceptible to CCl4-induced hepatotoxicity. These species comparisons were evaluated against toxicokinetic studies conducted in animals exposed by nose-only inhalation to 20 ppm 14C-labeled CCl4 for 4 hours. The toxicokinetic study results are consistent with the in vivo rates of metabolism, with rats eliminating less radioactivity associated with metabolism (14CO2 and urine/feces) and more radioactivity associated with the parent compound (radioactivity trapped on charcoal) compared to either hamsters or mice. The in vivo metabolic constants determined here, together with in vitro constants determined using rat, mouse, hamster and human liver microsomes, were used to estimate human in vivo metabolic rates of 1.49 mg/hr/kg body weight and 0.25 mg/L for Vmax and Km, respectively. Normalizing the rate of metabolism (Vmax/Km) by mg liver protein, the rate of metabolism of CCl4 differs across species, with hamster > mouse& > rat > human.

  7. Cholecystokinin-33 acutely attenuates food foraging, hoarding and intake in Siberian hamsters.

    Science.gov (United States)

    Teubner, Brett J W; Bartness, Timothy J

    2010-04-01

    Neurochemicals that stimulate food foraging and hoarding in Siberian hamsters are becoming more apparent, but we do not know if cessation of these behaviors is due to waning of excitatory stimuli and/or the advent of inhibitory factors. Cholecystokinin (CCK) may be such an inhibitory factor as it is the prototypic gastrointestinal satiety peptide and is physiologically important in decreasing food intake in several species including Siberian hamsters. Systemic injection of CCK-33 in laboratory rats decreases food intake, doing so to a greater extent than CCK-8. We found minimal effects of CCK-8 on food foraging and hoarding previously in Siberian hamsters, but have not tested CCK-33. Therefore, we asked: Does CCK-33 decrease normal levels or food deprivation-induced increases in food foraging, hoarding and intake? Hamsters were housed in a wheel running-based foraging system with simulated burrows to test the effects of peripheral injections of CCK-33 (13.2, 26.4, or 52.8 microg/kg body mass), with or without a preceding 56 h food deprivation. The highest dose of CCK-33 caused large baseline reductions in all three behaviors for the 1st hour post-injection compared with saline; in addition, the intermediate CCK-33 dose was sufficient to curtail food intake and foraging during the 1st hour. In food-deprived hamsters, we used a 52.8 microg/kg body mass dose of CCK-33 which decreased food intake, hoarding, and foraging almost completely compared with saline controls for 1h. Therefore, CCK-33 appears to be a potent inhibitor of food intake, hoarding, and foraging in Siberian hamsters. Copyright (c) 2009 Elsevier Inc. All rights reserved.

  8. Male Syrian hamsters experimentally infected with Helicobacter spp. of the H. bilis cluster develop MALT-associated gastrointestinal lymphomas

    Science.gov (United States)

    Woods, Stephanie E.; Ek, Courtney; Shen, Zeli; Feng, Yan; Ge, Zhongming; Muthupalani, Sureshkumar; Whary, Mark T.; Fox, James G.

    2015-01-01

    Background Aged hamsters naturally infected with novel Helicobacter spp. classified in the H. bilis cluster develop hepatobiliary lesions and typhlocolitis. Methods To determine if enterohepatic H. spp. contribute to disease, Helicobacter-free hamsters were experimentally infected with H. spp. after suppression of intestinal bacteria by tetracycline treatment of dams and pups. After antibiotic withdrawal, weanlings were gavaged with 4 H. bilis-like Helicobacter spp. isolated from hamsters or H. bilis ATCC 43879 isolated from human feces, and compared to controls (n = 7 per group). Results H. bilis 43879 dosed hamsters were necropsied at 33 WPI due to lack of detectable infection by fecal PCR; at necropsy, 5/7 were weakly PCR positive but lacked intestinal lesions. The remaining hamsters were maintained for ~95 WPI; chronic H. spp. infection in hamsters (6/7) was confirmed by PCR, bacterial culture, FISH and ELISA. Hamsters had mild to moderate typhlitis, and three of the male H. spp. infected hamsters developed small intestinal lymphoma, in contrast to one control. Of the three lymphomas in H. spp. infected hamsters, one was a focal ileal MALT B cell lymphoma, while the other two were multicentric small intestinal large B cell lymphomas involving both the MALT and extra-MALT mucosal sites with lymphoepithelial lesions. The lymphoma in the control hamster was a diffuse small intestinal lymphoma with a mixed population of T and B cells. Conclusions Results suggest persistent H. spp. infection may augment risk for gastrointestinal MALT origin lymphomas. This model is consistent with H. pylori/heilmannii associated MALT lymphoma in humans and could be further utilized to investigate mechanisms of intestinal lymphoma development. PMID:26348390

  9. Rare case of a strangulated intercostal flank hernia following open nephrectomy: A case report and review of literature.

    Science.gov (United States)

    Akinduro, Oluwaseun O; Jones, Frank; Turner, Jacquelyn; Cason, Frederick; Clark, Clarence

    2015-01-01

    Flank incisions may be associated with incisional flank hernias, which may progress to incarceration and strangulation. Compromised integrity of the abdominal and intercostal musculature due to previous surgery may be associated with herniation of abdominal contents into the intercostal space. There have been six previously reported cases of herniation into the intercostal space after a flank incision for a surgical procedure. This case highlights the clinical picture associated with an emergent strangulated hernia and highlights the critical steps in its management. We present a case of a 79-year-old adult man with multiple comorbidities presenting with a strangulated flank hernia secondary to an intercostal incision for a right-sided open nephrectomy. The strangulated hernia required emergent intervention including right-sided hemi-colectomy with ileostomy and mucous fistula. Abdominal incisional hernias are rare and therefore easily overlooked, but may result in significant morbidity or even death in the patient.. The diagnosis can be made with a thorough clinical examination and ultrasound or computed topographical investigation. Once a hernia has become incarcerated, emergent surgical management is necessary to avoid strangulation and small bowel obstruction. Urgent diagnosis and treatment of this extremely rare hernia is paramount especially in the setting of strangulation. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. DNA variants within the 5'-flanking region of milk-protein-encoding genes II. The β-lactoglobulin-encoding gene.

    Science.gov (United States)

    Wagner, V A; Schild, T A; Geldermann, H

    1994-09-01

    For the detection of polymorphisms within the 5'-flanking region of the β-lactoglobulin (-LG) -encoding gene a nucleotide sequence containing 795 bp of the promoter and 59 bp of exon I was cloned and sequenced. After comparing the sequence from the DNA of 11 diverse cows (different breeds and milk-protein yields), 14 singlebp substitutions were identified within the 5'-flanking region and two in the 5'-untranslated region (5'-UTR) of exon I. Some of the variants are located in potential binding sites for trans-acting factors or in the 5'-UTR. A PCR-based RFLP analysis was performed, and the genotypes of an additional 60 cows were identified at five variable 5'-flanking sites. The results reveal three frequent combinations between the A and B alleles of the protein-coding region and the novel 5'-flanking DNA variants. This finding may explain the differences of the protein-variant-dependent β-LG synthesis (A>B) observed in vivo. A sequence comparison of the bovine and ovine promoters reveals an homology of 92.8% and shows a higher degree of conservation between positions -600 and -300.

  11. Landscape-scale drivers of glacial ecosystem change in the montane forests of the eastern Andean flank, Ecuador

    NARCIS (Netherlands)

    Loughlin, N.J.D.; Gosling, W.D.; Coe, A.L.; Gulliver, P.; Mothes, P.; Montoya, E.

    2018-01-01

    Understanding the impact of landscape-scale disturbance events during the last glacial period is vital in accurately reconstructing the ecosystem dynamics of montane environments. Here, a sedimentary succession from the tropical montane cloud forest of the eastern Andean flank of Ecuador provides

  12. Rare case of a strangulated intercostal flank hernia following open nephrectomy: A case report and review of literature

    Science.gov (United States)

    Akinduro, Oluwaseun O.; Jones, Frank; Turner, Jacquelyn; Cason, Frederick; Clark, Clarence

    2015-01-01

    Introduction Flank incisions may be associated with incisional flank hernias, which may progress to incarceration and strangulation. Compromised integrity of the abdominal and intercostal musculature due to previous surgery may be associated with herniation of abdominal contents into the intercostal space. There have been six previously reported cases of herniation into the intercostal space after a flank incision for a surgical procedure. This case highlights the clinical picture associated with an emergent strangulated hernia and highlights the critical steps in its management. Presentation of case We present a case of a 79-year-old adult man with multiple comorbidities presenting with a strangulated flank hernia secondary to an intercostal incision for a right-sided open nephrectomy. The strangulated hernia required emergent intervention including right-sided hemi-colectomy with ileostomy and mucous fistula. Discussion Abdominal incisional hernias are rare and therefore easily overlooked, but may result in significant morbidity or even death in the patient.. The diagnosis can be made with a thorough clinical examination and ultrasound or computed topographical investigation. Once a hernia has become incarcerated, emergent surgical management is necessary to avoid strangulation and small bowel obstruction. Conclusion Urgent diagnosis and treatment of this extremely rare hernia is paramount especially in the setting of strangulation. PMID:26629848

  13. Application of the direct method of ISO 10848 to flanking transmission through double leaf gypsum board walls

    NARCIS (Netherlands)

    Schoenwald, S.; Nightingale, T.; Gerretsen, E.; Martin, H.

    2006-01-01

    ISO 10848 describes two methods to measure flanking transmission between two adjacent rooms. The first is the indirect method and is based on the measurement of sound pressure level difference between the two rooms. The second is the direct method and uses the surface velocity level difference of

  14. Contrasting neogene denudation histories of different structural regions in the transantarctic mountains rift flank constrained by cosmogenic isotope measurements

    NARCIS (Netherlands)

    Wateren, F.M. van der; Dunai, T.J.; Balen, R.T. van; Klas, W.; Verbers, A.L.L.M.; Passchier, S.; Herpers, U.

    1999-01-01

    Separate regions within the Transantarctic Mountains, the uplifted flank of the West Antarctic rift system, appear to have distinct Neogene histories of glaciation and valley downcutting. Incision of deep glacial outlet valleys occurred at different times throughout central and northern Victoria

  15. Improved enantioselective conversion of styrene epoxides and meso-epoxides through epoxide hydrolases with a mutated nucleophile-flanking residue

    NARCIS (Netherlands)

    van Loo, Bert; Kingma, Jaap; Heyman, Gertjan; Wittenaar, Alex; Lutje Spelberg, Jeffrey H.; Sonke, Theo; Janssen, Dick B.

    2009-01-01

    In epoxide hydrolase from Agrobacterium radiobacter (EchA), phenylalanine 108 flanks the nucleophilic aspartate and forms part of the substrate-binding pocket. The influence of mutations at this position on the activity and enantioselectivity of the enzyme was investigated. Screening for improved

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

    DEFF Research Database (Denmark)

    Hjortoe, Gertrud Malene; Weilguny, Dietmar; 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...

  17. 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...

  18. Circadian clock resetting by sleep deprivation without exercise in Syrian hamsters: dark pulses revisited.

    Science.gov (United States)

    Mistlberger, Ralph E; Belcourt, Jodi; Antle, Michael C

    2002-06-01

    Circadian rhythms in Syrian hamsters can be phase shifted by procedures that stimulate wheel running ("exercise") in the mid-subjective day (the hamster's usual sleep period). The authors recently demonstrated that keeping hamsters awake by gentle handling, without continuous running, is sufficient to mimic this effect. Here, the authors assessed whether wakefulness, independent of wheel running, also mediates phase shifts to dark pulses during the midsubjective day in hamsters free-running in constant light (LL). With running wheels locked during a 3 h dark pulse on day 3 of LL, hamsters (N = 16) averaged only 43+/-15 min of spontaneous wake time and phase shifted only 24+/-43 min. When wheels were open during a dark pulse, two hamsters remained awake, ran continuously, and showed phase advance shifts of 7.3 h and 8.7 h, respectively, whereas the other hamsters were awake awake for 3 h without running. Additional time in LL (10 and 20 days) did not potentiate the waking or phase shift response to dark pulses. When all hamsters were sleep deprived with wheels locked during a dark pulse, phase advance shifts averaged 261+/-110 min and ranged up to 7.3 h. These shifts are large compared to those previously observed in response to the 3 h sleep deprivation procedure. Additional tests revealed that this potentiated shift response is dependent on LL prior to sleep deprivation but not LL after sleep deprivation. A final sleep deprivation test showed that a small part of the potentiation may be due to suppression of spontaneous wheel running by LL. These results indicate that some correlate of waking, other than continuous running, mediates the phase-shifting effect of dark pulses in the mid-subjective day. The mechanism by which LL potentiates shifting remains to be determined. The lack of effect of subsequent LL on the magnitude of shifts to sleep deprivation in the dark suggests that LL reduces responsivity to light by processes that take >3 h of dark to reverse.

  19. The Effects of Vaccinium myrtillus Extract on Hamster Pial Microcirculation during Hypoperfusion-Reperfusion Injury.

    Directory of Open Access Journals (Sweden)

    Teresa Mastantuono

    Full Text Available The present study was aimed to assess the in vivo hamster pial microvessel alterations due to 30 min transient bilateral common carotid artery occlusion (BCCAO and reperfusion (60 min; moreover, the neuroprotective effects of Vaccinium myrtillus extract, containing 34.7% of anthocyanins, were investigated.Two groups of male hamsters were used: the first fed with control diet and the other with Vaccinium myrtillus supplemented diet. Hamster pial microcirculation was visualized by fluorescence microscopy through an open cranial window. Pial arterioles were classified according to Strahler's method.In age-matched control diet-fed hamsters, BCCAO caused a decrease in diameter of all arterioles. At the end of reperfusion, the reduction of diameter in order 3 arterioles was by 8.4 ± 3.1%, 10.8 ± 2.3% and 12.1 ± 1.1% of baseline in the 2, 4 and 6 month control diet-fed hamsters, respectively. Microvascular permeability and leukocyte adhesion were markedly enhanced, while perfused capillary length (PCL decreased. The response to acetylcholine and papaverine topical application was impaired; 2'-7'-dichlorofluoresceine-diacetate assay demonstrated a significant ROS production. At the end of BCCAO, in age-matched Vaccinium myrtillussupplemented diet-fed hamsters, the arteriolar diameter did not significantly change compared to baseline. After 60 min reperfusion, order 3 arterioles dilated by 9.3 ± 2.4%, 10.6 ± 3.1% and 11.8 ± 2.7% of baseline in the 2, 4 and 6 month Vaccinium myrtillus supplemented diet-fed hamsters, respectively. Microvascular leakage and leukocyte adhesion were significantly reduced in all groups according to the time-dependent treatment, when compared with the age-matched control diet-fed hamsters. Similarly, the reduction in PCL was progressively prevented. Finally, the response to acetylcholine and papaverine topical application was preserved and there was no significant increase in ROS production in all groups.In conclusion

  20. The Effects of Vaccinium myrtillus Extract on Hamster Pial Microcirculation during Hypoperfusion-Reperfusion Injury.

    Science.gov (United States)

    Mastantuono, Teresa; Starita, Noemy; Sapio, Daniela; D'Avanzo, Sabato Andrea; Di Maro, Martina; Muscariello, Espedita; Paterni, Marco; Colantuoni, Antonio; Lapi, Dominga

    2016-01-01

    The present study was aimed to assess the in vivo hamster pial microvessel alterations due to 30 min transient bilateral common carotid artery occlusion (BCCAO) and reperfusion (60 min); moreover, the neuroprotective effects of Vaccinium myrtillus extract, containing 34.7% of anthocyanins, were investigated. Two groups of male hamsters were used: the first fed with control diet and the other with Vaccinium myrtillus supplemented diet. Hamster pial microcirculation was visualized by fluorescence microscopy through an open cranial window. Pial arterioles were classified according to Strahler's method. In age-matched control diet-fed hamsters, BCCAO caused a decrease in diameter of all arterioles. At the end of reperfusion, the reduction of diameter in order 3 arterioles was by 8.4 ± 3.1%, 10.8 ± 2.3% and 12.1 ± 1.1% of baseline in the 2, 4 and 6 month control diet-fed hamsters, respectively. Microvascular permeability and leukocyte adhesion were markedly enhanced, while perfused capillary length (PCL) decreased. The response to acetylcholine and papaverine topical application was impaired; 2'-7'-dichlorofluoresceine-diacetate assay demonstrated a significant ROS production. At the end of BCCAO, in age-matched Vaccinium myrtillussupplemented diet-fed hamsters, the arteriolar diameter did not significantly change compared to baseline. After 60 min reperfusion, order 3 arterioles dilated by 9.3 ± 2.4%, 10.6 ± 3.1% and 11.8 ± 2.7% of baseline in the 2, 4 and 6 month Vaccinium myrtillus supplemented diet-fed hamsters, respectively. Microvascular leakage and leukocyte adhesion were significantly reduced in all groups according to the time-dependent treatment, when compared with the age-matched control diet-fed hamsters. Similarly, the reduction in PCL was progressively prevented. Finally, the response to acetylcholine and papaverine topical application was preserved and there was no significant increase in ROS production in all groups. In conclusion, Vaccinium

  1. The Syrian Hamster Pineal Gland Responds to Isoproterenol in Vivo at Night

    Science.gov (United States)

    1987-01-01

    Society Printed in U.S.A. A THE SYRIAN HAMSTER PINEAL GLAND RESPONDS TO ISOPROTERENOL IN VIVO AT NIGHT George M. Vaughan 1 and Russel J. Reiter 2 1US...then kept in light for 2 h, pineal melatonin was equally low 0 • after ISO or vehicle injection. The Syrian hamster pineal gland can respond in vivo...responsiveness during the day, pineal highly concentrated at the pinealocyte glands taken 6 1/2 h into the night after a during the nocturnal surge of pineal

  2. Light at night alters daily patterns of cortisol and clock proteins in female Siberian hamsters.

    Science.gov (United States)

    Bedrosian, T A; Galan, A; Vaughn, C A; Weil, Z M; Nelson, R J

    2013-06-01

    Humans and other organisms have adapted to a 24-h solar cycle in response to life on Earth. The rotation of the planet on its axis and its revolution around the sun cause predictable daily and seasonal patterns in day length. To successfully anticipate and adapt to these patterns in the environment, a variety of biological processes oscillate with a daily rhythm of approximately 24 h in length. These rhythms arise from hierarchally-coupled cellular clocks generated by positive and negative transcription factors of core circadian clock gene expression. From these endogenous cellular clocks, overt rhythms in activity and patterns in hormone secretion and other homeostatic processes emerge. These circadian rhythms in physiology and behaviour can be organised by a variety of cues, although they are most potently entrained by light. In recent history, there has been a major change from naturally-occurring light cycles set by the sun, to artificial and sometimes erratic light cycles determined by the use of electric lighting. Virtually every individual living in an industrialised country experiences light at night (LAN) but, despite its prevalence, the biological effects of such unnatural lighting have not been fully considered. Using female Siberian hamsters (Phodopus sungorus), we investigated the effects of chronic nightly exposure to dim light on daily rhythms in locomotor activity, serum cortisol concentrations and brain expression of circadian clock proteins (i.e. PER1, PER2, BMAL1). Although locomotor activity remained entrained to the light cycle, the diurnal fluctuation of cortisol concentrations was blunted and the expression patterns of clock proteins in the suprachiasmatic nucleus and hippocampus were altered. These results demonstrate that chronic exposure to dim LAN can dramatically affect fundamental cellular function and emergent physiology. © 2013 British Society for Neuroendocrinology.

  3. Geologic map of the northeast flank of Mauna Loa volcano, Island of Hawai'i, Hawaii

    Science.gov (United States)

    Trusdell, Frank A.; Lockwood, John P.

    2017-05-01

    SummaryMauna Loa, the largest volcano on Earth, has erupted 33 times since written descriptions became available in 1832. Some eruptions were preceded by only brief seismic unrest, while others followed several months to a year of increased seismicity.The majority of the eruptions of Mauna Loa began in the summit area (>12,000-ft elevation; Lockwood and Lipman, 1987); yet the Northeast Rift Zone (NERZ) was the source of eight flank eruptions since 1843 (table 1). This zone extends from the 13,680-ft-high summit towards Hilo (population ~60,000), the second largest city in the State of Hawaii. Although most of the source vents are farther than 30 km away, the 1880 flow from one of the vents extends into Hilo, nearly reaching Hilo Bay. The city is built entirely on flows erupted from the NERZ, most older than that erupted in 1843.Once underway, Mauna Loa's eruptions can produce lava flows that reach the sea in less than 24 hours, severing roads and utilities in their path. For example, lava flows erupted from the Southwest Rift Zone (SWRZ) in 1950 advanced at an average rate of 9.3 km per hour, and all three lobes reached the ocean within approximately 24 hours (Finch and Macdonald, 1953). The flows near the eruptive vents must have traveled even faster.In terms of eruption frequency, pre-eruption warning, and rapid flow emplacement, Mauna Loa poses an enormous volcanic-hazard threat to the Island of Hawai‘i. By documenting past activity and by alerting the public and local government officials of our findings, we can anticipate the volcanic hazards and substantially mitigate the risks associated with an eruption of this massive edifice.From the geologic record, we can deduce several generalized facts about the geologic history of the NERZ. The middle to the uppermost section of the rift zone were more active in the past 4,000 years than the lower part, perhaps due to buttressing of the lower east rift zone by Mauna Kea and Kīlauea volcanoes. The historical flows

  4. Spatial Distribution of Rolled up Kelvin-Helmholtz Vortices at Earth's Dayside and Flank Magnetopause

    Science.gov (United States)

    Taylor, M. G. G. T.; Hasegawa, H.; Lavraud, B.; Phan, T.; Escoubet, C. P.; Dunlop, M. W.; Bogdanova, Y. V.; Borg, A. L.; Volwerk, M.; Berchem, J.; hide

    2012-01-01

    The Kelvin-Helmholtz Instability (KHI) can drive waves at the magnetopause. These waves can grow to form rolled-up vortices and facilitate transfer of plasma into the magnetosphere. To investigate the persistence and frequency of such waves at the magnetopause we have carried out a survey of all Double Star 1 magnetopause crossings, using a combination of ion and magnetic field measurements. Using criteria originally used in a Geotail study made by Hasegawa et al. (2006) (forthwith referred to as H2006), 17 candidate events were identified from the entire TC-1 mission (covering 623 orbits where the magnetopause was sampled), a majority of which were on the dayside of the terminator. The relationship between density and shear velocity was then investigated, to identify the predicted signature of a rolled up vortex from H2006 and all 17 events exhibited some level of rolled up behavior. The location of the events had a clear dawn-dusk asymmetry, with 12 (71 %) on the post noon, dusk flank suggesting preferential growth in this region.

  5. Long-period seismic events with strikingly regular temporal patterns on Katla volcano's south flank (Iceland)

    CERN Document Server

    Sgattoni, Giulia; Guðmundsson, Ólafur; Einarsson, Páll; Tryggvason, Ari; Lund, Björn; Lucchi, Federico

    2015-01-01

    Katla is a threatening volcano in Iceland, partly covered by the M\\'yrdalsj\\"okull ice cap. The volcano has a large caldera with several active geothermal areas. A peculiar cluster of long-period seismic events started on Katla's south flank in July 2011, during an unrest episode in the caldera that culminated in a glacier outburst. The seismic events were tightly clustered at shallow depth in the Gvendarfell area, 4 km south of the caldera, under a small glacier stream on the southern margin of M\\'yrdalsj\\"okull. No seismic events were known to have occurred in this area before. The most striking feature of this seismic cluster is its temporal pattern, characterized by regular intervals between repeating seismic events, modulated by a seasonal variation. Remarkable is also the stability of both the time and waveform features over a long time period, around 3.5 years. No comparable examples have been found in the literature. Both volcanic and glacial processes can produce similar waveforms and therefore have ...

  6. Petrology of parasitic and eccentric cones on the flanks and base of Somma-Vesuvius

    Science.gov (United States)

    Macdonald, Ray; Bagiński, Bogusław; Rolandi, Giuseppe; De Vivo, Benedetto; Kopczyńska, Anna

    2016-02-01

    Parasitic and eccentric cones on the flanks and at the base of Somma-Vesuvius potentially provide information on the plumbing system of the complex. We present geochemical data for minerals, glasses and rocks from the Pollena and Cercola cones. The rocks are phonotephrites and a basaltic trachyandesite. A volumetrically dominant type contains phenocrysts of olivine, clinopyroxene, leucite, plagioclase ± apatite ± Fe-Ti-oxides. A second type is phlogopite-phyric. Low magnesium-numbers (62-49) and Ni abundances (≤32 ppm) indicate that the primary magmas underwent crustal-level fractionation but the cores of olivine and clinopyroxene phenocrysts carry records of the parental magmas. Geochemical data indicate that the rocks form more than one magmatic lineage. Matrix glasses point to low-pressure fractionation trends towards decreasing melt silica-undersaturation. The phlogopite-phyric rocks were derived from more hydrous magmas than those lacking phlogopite phenocrysts, perhaps at higher pressures. Phenocryst assemblages are difficult to reconcile with published experimental work and it is likely that they are far from equilibrium assemblages. The cone magmas were probably derived from high levels within the main plumbing system via lateral transport.

  7. Spatial distribution of rolled up Kelvin-Helmholtz vortices at Earth's dayside and flank magnetopause

    Directory of Open Access Journals (Sweden)

    M. G. G. T. Taylor

    2012-06-01

    Full Text Available The Kelvin-Helmholtz Instability (KHI can drive waves at the magnetopause. These waves can grow to form rolled-up vortices and facilitate transfer of plasma into the magnetosphere. To investigate the persistence and frequency of such waves at the magnetopause we have carried out a survey of all Double Star 1 magnetopause crossings, using a combination of ion and magnetic field measurements. Using criteria originally used in a Geotail study made by Hasegawa et al. (2006 (forthwith referred to as H2006, 17 candidate events were identified from the entire TC-1 mission (covering ~623 orbits where the magnetopause was sampled, a majority of which were on the dayside of the terminator. The relationship between density and shear velocity was then investigated, to identify the predicted signature of a rolled up vortex from H2006 and all 17 events exhibited some level of rolled up behavior. The location of the events had a clear dawn-dusk asymmetry, with 12 (71% on the post noon, dusk flank suggesting preferential growth in this region.

  8. Unusual presentation of cactus spines in the flank of an elderly man: a case report

    Directory of Open Access Journals (Sweden)

    Freeman Scott

    2010-05-01

    Full Text Available Abstract Introduction Splinters and spines of plant matter are common foreign bodies in skin wounds of the extremities, and often present embedded in the dermis or subcutaneous tissue. Vegetative foreign bodies are highly inflammatory and, if not completely removed, can cause infection, toxic reactions, or granuloma formation. Older patients are at increased risk for infection from untreated plant foreign bodies. The most common error in plant splinter and spine management is failure to detect their presence. Case presentation Here we report a case of cactus spines in an 84-year-old Caucasian man presenting on the right flank as multiple, red papules with spiny extensions. This presentation was unusual both in location and the spinous character of the lesions, and only after punch biopsy analysis was a diagnosis of cactus matter spines made. Conclusions Our patient presented with an unusual case of cactus spines that required histopathology for identification. Skin lesions with neglected foreign bodies are a common cause of malpractice claims. If not removed, foreign bodies of the skin, particularly in elderly individuals, can result in inflammatory and infectious sequela. This report underscores the importance of thoroughly evaluating penetrating skin lesions for the presence of foreign bodies, such as splinters and spines.

  9. Influence of PAS domain flanking regions on oligomerisation and redox signalling by NifL.

    Directory of Open Access Journals (Sweden)

    Richard Little

    Full Text Available Per-ARNT-Sim (PAS domains constitute a typically dimeric, conserved α/β tertiary fold of approximately 110 amino acids that perform signalling roles in diverse proteins from all kingdoms of life. The amino terminal PAS1 domain of NifL from Azotobacter vinelandii accommodates a redox-active FAD group; elevation of cytosolic oxygen concentrations result in FAD oxidation and a concomitant conformational re-arrangement that is relayed via a short downstream linker to a second PAS domain, PAS2. At PAS2, the signal is amplified and passed on to effector domains generating the 'on' (inhibitory state of the protein. Although the crystal structure of oxidised PAS1 reveals regions that contribute to the dimerisation interface, 21 amino acids at the extreme N-terminus of NifL, are unresolved. Furthermore, the structure and function of the linker between the two PAS domains has not been determined. In this study we have investigated the importance to signalling of residues extending beyond the core PAS fold. Our results implicate the N-terminus of PAS1 and the helical linker connecting the two PAS domains in redox signal transduction and demonstrate a role for these flanking regions in controlling the oligomerisation state of PAS1 in solution.

  10. Repair of naturally occurring mismatches can induce mutations in flanking DNA

    Science.gov (United States)

    Chen, Jia; Miller, Brendan F; Furano, Anthony V

    2014-01-01

    ‘Normal’ genomic DNA contains hundreds of mismatches that are generated daily by the spontaneous deamination of C (U/G) and methyl-C (T/G). Thus, a mutagenic effect of their repair could constitute a serious genetic burden. We show here that while mismatches introduced into human cells on an SV40-based episome were invariably repaired, this process induced mutations in flanking DNA at a significantly higher rate than no mismatch controls. Most mutations involved the C of TpC, the substrate of some single strand-specific APOBEC cytidine deaminases, similar to the mutations that can typify the ‘mutator phenotype’ of numerous tumors. siRNA knockdowns and chromatin immunoprecipitation showed that TpC preferring APOBECs mediate the mutagenesis, and siRNA knockdowns showed that both the base excision and mismatch repair pathways are involved. That naturally occurring mispairs can be converted to mutators, represents an heretofore unsuspected source of genetic changes that could underlie disease, aging, and evolutionary change. DOI: http://dx.doi.org/10.7554/eLife.02001.001 PMID:24843013

  11. Modeling ground deformation associated with the destructive earthquakes occurring on Mt. Etna's southeastern flank in 1984

    Science.gov (United States)

    Cannavò, Flavio; Gambino, Salvatore; Puglisi, Biagio; Velardita, Rosanna

    2016-11-01

    The Timpe Fault System is the source of very shallow but destructive earthquakes that affect several towns and villages on the eastern flank of Mt. Etna (Italy). In 1984, several seismic events, and specifically on 19 and 25 October, caused one fatality, 12 injuries and produced serious damage in the Zafferana and Acireale territories. This seismicity was mainly related to the activity of the Fiandaca Fault, one of the structures belonging to the Timpe Fault System. We inverted ground deformation data collected by a geodimeter trilateration network set up in 1977 at a low altitude along the eastern side of the volcano in order to define the Timpe Fault System faulting mechanisms linked to the seismicity in 1984. We have found that in the period May 1980-October 1984, the Fiandaca Fault was affected by a strike-slip and normal dip-slip of about 20.4 and 12.7 cm respectively. This result is kinematically consistent with field observations of the coseismic ground ruptures along the fault but it is notably large compared to displacements estimated by seismicity, then suggesting that most of the slip over the fault plane was aseismic. The results once again confirm how seismicity and its relation with ground ruptures and creep displacement represent a very high hazard to the several towns and villages situated along the Timpe Fault System.

  12. Discovery of a flank caldera and very young glacial activity at Hecates Tholus, Mars.

    Science.gov (United States)

    Hauber, Ernst; van Gasselt, Stephan; Ivanov, Boris; Werner, Stephanie; Head, James W; Neukum, Gerhard; Jaumann, Ralf; Greeley, Ronald; Mitchell, Karl L; Muller, Peter

    2005-03-17

    The majority of volcanic products on Mars are thought to be mafic and effusive. Explosive eruptions of basic to ultrabasic chemistry are expected to be common, but evidence for them is rare and mostly confined to very old surface features. Here we present new image and topographic data from the High Resolution Stereo Camera that reveal previously unknown traces of an explosive eruption at 30 degrees N and 149 degrees E on the northwestern flank of the shield volcano Hecates Tholus. The eruption created a large, 10-km-diameter caldera approximately 350 million years ago. We interpret these observations to mean that large-scale explosive volcanism on Mars was not confined to the planet's early evolution. We also show that glacial deposits partly fill the caldera and an adjacent depression. Their age, derived from crater counts, is about 5 to 24 million years. Climate models predict that near-surface ice is not stable at mid-latitudes today, assuming a thermo-dynamic steady state. Therefore, the discovery of very young glacial features at Hecates Tholus suggests recent climate changes. We show that the absolute ages of these very recent glacial deposits correspond very well to a period of increased obliquity of the planet's rotational axis.

  13. SR Proteins Induce Alternative Exon Skipping through Their Activities on the Flanking Constitutive Exons▿

    Science.gov (United States)

    Han, Joonhee; Ding, Jian-Hua; Byeon, Cheol W.; Kim, Jee H.; Hertel, Klemens J.; Jeong, Sunjoo; Fu, Xiang-Dong

    2011-01-01

    SR proteins are well known to promote exon inclusion in regulated splicing through exonic splicing enhancers. SR proteins have also been reported to cause exon skipping, but little is known about the mechanism. We previously characterized SRSF1 (SF2/ASF)-dependent exon skipping of the CaMKIIδ gene during heart remodeling. By using mouse embryo fibroblasts derived from conditional SR protein knockout mice, we now show that SR protein-induced exon skipping depends on their prevalent actions on a flanking constitutive exon and requires collaboration of more than one SR protein. These findings, coupled with other established rules for SR proteins, provide a theoretical framework to understand the complex effect of SR protein-regulated splicing in mammalian cells. We further demonstrate that heart-specific CaMKIIδ splicing can be reconstituted in fibroblasts by downregulating SR proteins and upregulating a RBFOX protein and that SR protein overexpression impairs regulated CaMKIIδ splicing and neuronal differentiation in P19 cells, illustrating that SR protein-dependent exon skipping may constitute a key strategy for synergism with other splicing regulators in establishing tissue-specific alternative splicing critical for cell differentiation programs. PMID:21135118

  14. SR proteins induce alternative exon skipping through their activities on the flanking constitutive exons.

    Science.gov (United States)

    Han, Joonhee; Ding, Jian-Hua; Byeon, Cheol W; Kim, Jee H; Hertel, Klemens J; Jeong, Sunjoo; Fu, Xiang-Dong

    2011-02-01

    SR proteins are well known to promote exon inclusion in regulated splicing through exonic splicing enhancers. SR proteins have also been reported to cause exon skipping, but little is known about the mechanism. We previously characterized SRSF1 (SF2/ASF)-dependent exon skipping of the CaMKIIδ gene during heart remodeling. By using mouse embryo fibroblasts derived from conditional SR protein knockout mice, we now show that SR protein-induced exon skipping depends on their prevalent actions on a flanking constitutive exon and requires collaboration of more than one SR protein. These findings, coupled with other established rules for SR proteins, provide a theoretical framework to understand the complex effect of SR protein-regulated splicing in mammalian cells. We further demonstrate that heart-specific CaMKIIδ splicing can be reconstituted in fibroblasts by downregulating SR proteins and upregulating a RBFOX protein and that SR protein overexpression impairs regulated CaMKIIδ splicing and neuronal differentiation in P19 cells, illustrating that SR protein-dependent exon skipping may constitute a key strategy for synergism with other splicing regulators in establishing tissue-specific alternative splicing critical for cell differentiation programs.

  15. Comparison of DNA walking methods for isolation of transgene-flanking regions in GM potato.

    Science.gov (United States)

    Cullen, Danny; Harwood, Wendy; Smedley, Mark; Davies, Howard; Taylor, Mark

    2011-09-01

    An important aspect in the safety assessment of transgenic plants is the exact location of transgene insertion sites within the host genome. However, robust standard operating procedures are not currently available. Using potato as a test species, different methodologies for the determination of insertion sites using a range of published protocols and commercially available kits were assessed in transgenic lines of varying degrees of complexity, from low copy number to complex re-transformed and co-transformed lines. Three commercial kits, APAgene™ GOLD Genome Walking Kit (BIO S&T), DNA Walking SpeedUp™ Kit II (Seegene), and Universal Vectorette™ System (Sigma) were compared with an adaptor-mediated PCR technique. Overall, the APAgene™ kit was used with a high success rate with low copy number potato lines, and also more complex co- and re-transformed lines, and adhering to key confirmation steps it was possible to obtain flanking sequence ranging in size from 300 to 2,500 bp and eliminate PCR artefacts from the analysis.

  16. The role of viscous magma mush spreading in volcanic flank motion at Kīlauea Volcano, Hawai‘i

    Science.gov (United States)

    Plattner, C.; Amelung, F.; Baker, S.; Govers, R.; Poland, M.

    2013-01-01

    Multiple mechanisms have been suggested to explain seaward motion of the south flank of Kīlauea Volcano, Hawai‘i. The consistency of flank motion during both waxing and waning magmatic activity at Kīlauea suggests that a continuously acting force, like gravity body force, plays a substantial role. Using finite element models, we test whether gravity is the principal driver of long-term motion of Kīlauea's flank. We compare our model results to geodetic data from Global Positioning System and interferometric synthetic aperture radar during a time period with few magmatic and tectonic events (2000-2003), when deformation of Kīlauea was dominated by summit subsidence and seaward motion of the south flank. We find that gravity-only models can reproduce the horizontal surface velocities if we incorporate a regional décollement fault and a deep, low-viscosity magma mush zone. To obtain quasi steady state horizontal surface velocities that explain the long-term seaward motion of the flank, we find that an additional weak zone is needed, which is an extensional rift zone above the magma mush. The spreading rate in our model is mainly controlled by the magma mush viscosity, while its density plays a less significant role. We find that a viscosity of 2.5 × 1017–2.5 × 1019 Pa s for the magma mush provides an acceptable fit to the observed horizontal surface deformation. Using high magma mush viscosities, such as 2.5 × 1019 Pa s, the deformation rates remain more steady state over longer time scales. These models explain a significant amount of the observed subsidence at Kīlauea's summit. Some of the remaining subsidence is probably a result of magma withdrawal from subsurface reservoirs

  17. Bio F1B hamster: a unique animal model with reduced lipoprotein lipase activity to investigate nutrient mediated regulation of lipoprotein metabolism

    OpenAIRE

    Cheema, Sukhinder Kaur; Cornish, Marion L

    2007-01-01

    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. ...

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

    Science.gov (United States)

    Schöttner, Konrad; Hauer, Jane; Weinert, Dietmar

    To investigate the role of non-parametric light effects in entrainment, Djungarian hamsters of two different circadian phenotypes were exposed to skeleton photoperiods, or to light pulses at different circadian times, to compile phase response curves (PRCs). Wild-type (WT) hamsters show daily rhythms of locomotor activity in accord with the ambient light/dark conditions, with activity onset and offset strongly coupled to light-off and light-on, respectively. Hamsters of the delayed activity onset (DAO) phenotype, in contrast, progressively delay their activity onset, whereas activity offset remains coupled to light-on. The present study was performed to better understand the underlying mechanisms of this phenomenon. Hamsters of DAO and WT phenotypes were kept first under standard housing conditions with a 14:10 h light-dark cycle, and then exposed to skeleton photoperiods (one or two 15-min light pulses of 100 lx at the times of the former light-dark and/or dark-light transitions). In a second experiment, hamsters of both phenotypes were transferred to constant darkness and allowed to free-run until the lengths of the active (α) and resting (ρ) periods were equal (α:ρ = 1). At this point, animals were then exposed to light pulses (100 lx, 15 min) at different circadian times (CTs). Phase and period changes were estimated separately for activity onset and offset. When exposed to skeleton-photoperiods with one or two light pulses, the daily activity patterns of DAO and WT hamsters were similar to those obtained under conditions of a complete 14:10 h light-dark cycle. However, in the case of giving only one light pulse at the time of the former light-dark transition, animals temporarily free-ran until activity offset coincided with the light pulse. These results show that photic entrainment of the circadian activity rhythm is attained primarily via non-parametric mechanisms, with the "morning" light pulse being the essential cue. In the second experiment, typical

  19. Embryonic delivered dose of isotretinoin (13-cis-retinoic acid) and its metabolites in hamsters.

    Science.gov (United States)

    Eckhoff, C; Willhite, C C

    1997-09-01

    All-trans-retinoic acid (all-trans-RA) is required in normal embryogenesis and both deficiency and excess are teratogenic. Isotretinoin (13-cis-RA) is teratogenic in all species examined; based on administered dose, humans appear most sensitive, followed by (in order or decreasing sensitivity) monkey, rabbit, hamster, mouse, and rat. Identification of the teratogenic threshold in these species is difficult because RAs are normal physiologic constituents. The rabbit no-observed-adverse-effect-level (NOAEL) and lowest-observed-adverse-effect-level (LOAEL) administered doses (3 and 15 mg/kg/day, respectively, on gestation Days 8-11) are less than the corresponding values in hamster (7.5 and 37.5 mg/kg/day, respectively, on gestation Days 7 and 8), but drawing conclusions from administered dose alone ignores differences in absorbed, metabolized, and embryonic delivered dose. Therefore, distribution and metabolism studies of 13-cis-RA at the NOAEL and LOAEL in pregnant hamsters were performed and plasma and tissue concentrations of parent compound and metabolites were compared to those found in rabbits. Metabolites of 13-cis-RA common to all species include three RAs (all-trans-RA, all-trans-4-oxoRA, 13-cis-4-oxoRA) and the glucuronide conjugate of 13-cis-RA (13-cis-RAG). As in rabbits, we found 13-cis-4-oxoRA also to be the major metabolite of 13-cis-RA in hamster plasma, peripheral tissues, and embryo. Of maternal tissues, peak 13-cis-RA concentrations were highest in liver. Total concentration of RA (13-cis-RA + 13-cis-4-oxoRA + all-trans-RA + all-trans-4-oxoRA) per gram of wet tissue was greatest in maternal liver, followed by that in lung, adipose tissue, muscle, kidney, and brain. At the NOAEL, total RA plasma Cmax in hamster was 6 times that in rabbit; at the LOAEL, hamster plasma total RA Cmax was 4 times that in rabbit. Hamster absorbed and metabolized dose (as AUC of plasma total RA) at the NOAEL and LOAEL was 2.6 and 2.4 times that in rabbit, respectively. In

  20. Assignment of genes encoding metallothioneins I and II to Chinese hamster chromosomes 3. Evidence for the role of chromosome rearrangement in gene amplification

    Energy Technology Data Exchange (ETDEWEB)

    Stallings, R.L.; Munk, A.C.; Longmire, J.L.; Hildebrand, C.E.; Crawford, B.D.

    1984-12-01

    Cadmium resistant (Cd/sup r/) variants with coordinately amplified metallothionein I and II (MTI and MTII) genes have been derived from both Chinese hamster ovary and near-euploid Chinese hamster cell lines. Cytogenetic analyses of Cd/sup r/ variants consistently revealed breakage and rearrangement involving chromosome 3p. In situ hybridization with Chinese hamster MT-encoding cDNA probe localized amplified MT gene sequences near the translocation breakpoint involving chromosome 3p. These observations suggested that both functionally related, isometallothionein loci are linked on Chinese hamster chromosome 3. Southern blot analyses of DNAs isolated from a panel of Chinese hamster x mouse somatic cell hybrids which segregate hamster chromosomes confirmed that both MTI and MTII are located on chromosome 3. The authors speculate that rearrangement of chromosome 3p could be causally involved with the amplification of MT genes in Cd/sup r/ hamster cell lines. 34 references, 3 figures, 1 table.

  1. Immunosuppressive prednisolone enhances early cholangiocarcinoma in Syrian hamsters with liver fluke infection and administration of N-nitrosodimethylamine.

    Science.gov (United States)

    Juasook, Amornrat; Boonmars, Thidarut; Wu, Zhiliang; Loilome, Watcharin; Veteewuthacharn, Kulathida; Namwat, Nissana; Sudsarn, Pakkayanee; Wonkchalee, Orasa; Sriraj, Pranee; Aukkanimart, Ratchadawan

    2013-01-01

    Chronic infection with Opisthorchis viverrini for many years has been associated with the development of hepatobiliary diseases including cholangiocarcinoma. It is well known that inflammation is a key component of the tumor microenvironment, and that chronic inflammation plays an important role in tumorigenesis. Therefore, in this study cholangiocarcinogenesis was induced in Syrian hamsters in order to observe the cancer-related inflammation. The Syrian hamsters were divided into 5 groups: uninfected controls; normal Syrian hamsters infected with O. viverrini (OV); immunosuppressed Syrian hamsters infected with O. viverrini (OVis); normal Syrian hamsters infected with O. viverrini and administered N-nitrosodimethylamine (CCA); and immunosuppressed Syrian hamsters infected with O. viverrini and administered N-nitrosodimethylamine (CCAis). Syrian hamster livers were later observed for gross pathology and histopathological changes; COX2 was analyzed by immunohistochemical staining. We found a decreased number of inflammatory cells surrounding the hepatic bile duct in the OVis group, but not in the OV and CCAis groups. However, in the CCAis group (with suppressed immunity) early appearance and greater severity of cholangiocarcinoma were observed; gross pathological examination revealed many cancer nodularities on the liver surface, and histopathological studies showed the presence of cancer cells, findings which correlated with the predominant expression of COX2. The present study suggests that host immune responses are intended to ameliorate pathology, and they are also crucially associated with pathogenesis in O. viverrini infection; the unbalancing of host immunity may enhance cancer-related inflammation.

  2. 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

  3. Animal Models of Leptospirosis: Of Mice and Hamsters

    Science.gov (United States)

    Gomes-Solecki, Maria; Santecchia, Ignacio; Werts, Catherine

    2017-01-01

    Pathogenic Leptospira sp. are spirochetal bacteria responsible for leptospirosis, an emerging worldwide zoonosis. These spirochetes are very successful pathogens that infect a wide range of hosts such as fish, reptiles, birds, marsupials, and mammals. Transmission occurs when chronically infected animals excrete live bacteria in their urine, contaminating the environment. Leptospira sp. enter their hosts through damaged skin and mucosa. Chronically infected rats and mice are asymptomatic and are considered as important reservoirs of the disease. Infected humans may develop either a flu-like, usually mild illness with or without chronic asymptotic renal colonization, or a severe acute disease with kidney, liver, and heart failure, potentially leading to death. Leptospirosis is an economic burden on society due to health-care costs related to elevated morbidity of humans and loss of animals of agricultural interest. There are no effective vaccines against leptospirosis. Leptospira sp. are difficult to genetically manipulate which delays the pace of research progress. In this review, we discuss in an historical perspective how animal models have contributed to further our knowledge of leptospirosis. Hamsters, guinea pigs, and gerbils have been instrumental to study the pathophysiology of acute lethal leptospirosis and the Leptospira sp. genes involved in virulence. Chronic renal colonization has been mostly studied using experimentally infected rats. A special emphasis will be placed on mouse models, long thought to be irrelevant since they survive lethal infection. However, mice have recently been shown to be good models of sublethal infection leading to chronic colonization. Furthermore, congenic and transgenic mice have proven essential to study how innate immune cells interact with the pathogen and to understand the role of the toll-like receptor 4, which is important to control Leptospira sp. load and disease. The use of inbred and transgenic mouse models opens

  4. Flank Deformation Recorded during Cotopaxís Awakening in 2015

    Science.gov (United States)

    Mothes, Patricia A.; Nocquet, Jean-Mathieu; Yépez, Marco A.; Jarrín, Paúl A.; Ruiz, Mario C.; Gaunt, Elizabeth

    2016-04-01

    Cotopaxi, a large glacier-topped stratocone in the Ecuadorian Andes begin to display anomalous seismic activity in April, 2015 when the IGEPŃs 15 station seismic network registered an increase in long period seismic events which were located 3-12 km below the crater. Several weeks later a distinct inflationary pattern was observed at the VC1 tilt station, 6 km NE of the crater, where we recorded a steady ascent of 150 urads (daily rate 3.2 urads) through 01 June. The tilt rate tended to slow and displayed a start & stop tilt pattern through 01 August, when a strong positive trend again resumed. Subsequently, a strong positive tilt pattern was predominante and briefly stalled after the occurrence of 5 small explosions/strong emissions on 14 August, 2015. About September 1st and prior to the onset of a high-energy VT seismic swarm, a rapid onset of strong positive tilt is observed. Subsequently, even though 30-100 VT events were registered daily, the tilt pattern leveled off in November to December, presumably because the events were with magnitudes <1 and that the magma supply was waning? Five other tilt stations on the volcano are much less sensitive than the VC1 station and this probably reflects the ideal coupling of the VC1 tiltmeter to a thick lava flow, which descends from the summit. The seven station GPS network displayed a strong displacement to the NW-SW for the stations on the W-SW flanks and had accumulative horizontal changes of 1 cm with a maximum vertical displacement of 1 cm at stations on the S and E. The trends of stations on the NE flank, with their movement purely to the north and east are difficult to interpret, but may be related to a preferential movement upon an old avalanche scar surface and water lubrication. While the changes detected by GPS are small, they did increase through time and finally, like the tilt, leveled off in November, 2015. We believe that these pattern are the result of small batches of magma ascending up the conduit and

  5. Tool flank wear model and parametric optimization in end milling of metal matrix composite using carbide tool: Response surface methodology approach

    Directory of Open Access Journals (Sweden)

    R. Arokiadass

    2012-04-01

    Full Text Available Highly automated CNC end milling machines in manufacturing industry requires reliable model for prediction of tool flank wear. This model later can be used to predict the tool flank wear (VBmax according to the process parameters. In this investigation an attempt was made to develop an empirical relationship to predict the tool flank wear (VBmax of carbide tools while machining LM25 Al/SiCp incorporating the process parameters such as spindle speed (N, feed rate (f, depth of cut (d and various % wt. of silicon carbide (S. Response surface methodology (RSM was applied to optimizing the end milling process parameters to attain the minimum tool flank wear. Predicted values obtained from the developed model and experimental results are compared, and error <5 percent is observed. In addition, it is concluded that the flank wear increases with the increase of SiCp percentage weight in the MMC.

  6. Intranasal vaccination with leishmanial antigens protects golden hamsters (Mesocricetus auratus) against Leishmania (Viannia) Braziliensis infection.

    Science.gov (United States)

    da Silva-Couto, Luzinei; Ribeiro-Romão, Raquel Peralva; Saavedra, Andrea Franco; da Silva Costa Souza, Beatriz Lilian; Moreira, Otacílio Cruz; Gomes-Silva, Adriano; Rossi-Bergmann, Bartira; Da-Cruz, Alda Maria; Pinto, Eduardo Fonseca

    2015-01-01

    Previous results have shown that oral and intranasal administration of particulate Leishmania (Leishmania) amazonensis antigens (LaAg) partially protects mice against L. amazonensis infection. However, vaccination studies on species of the subgenus Viannia, the main causative agent of cutaneous and mucosal leishmaniasis in the Americas, have been hampered by the lack of easy-to-handle bio-models that accurately mimic the human disease. Recently, we demonstrated that the golden hamster is an appropriate model for studying the immunopathogenesis of cutaneous leishmaniasis caused by L. (Viannia) braziliensis. Using the golden hamster model, our current study investigated whether the protective effect of intranasal immunisation with LaAg can be extended to L. braziliensis infection. Golden hamsters vaccinated with either two intranasal (IN) doses of LaAg (10 µg) or two intramuscular doses of LaAg (20 µg) were challenged 2 weeks post-vaccination with L. braziliensis. The results showed that IN immunisation with LaAg significantly reduced lesion growth and parasitic load as well as serum IgG and IgG2 levels. At the experimental endpoint on day 114 post-infection, IN-immunised hamsters that were considered protected expressed IFN-γ and IL10 mRNA levels that returned to uninfected skin levels. In contrast to the nasal route, intramuscular (IM) immunisation failed to provide protection. These results demonstrate for the first time that the nasal route of immunisation can induce cross protection against L. braziliensis infection.

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

    Science.gov (United States)

    Lewis, Nathan E; Liu, Xin; Li, Yuxiang; Nagarajan, Harish; Yerganian, George; O'Brien, Edward; Bordbar, Aarash; Roth, Anne M; Rosenbloom, Jeffrey; Bian, Chao; Xie, Min; Chen, Wenbin; Li, Ning; Baycin-Hizal, Deniz; Latif, Haythem; Forster, Jochen; Betenbaugh, Michael J; Famili, Iman; Xu, Xun; Wang, Jun; Palsson, Bernhard O

    2013-08-01

    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 of this genetic diversity highlight the value of the hamster genome as the reference upon which CHO cells can be studied and engineered for protein production.

  8. Appropriateness of the hamster as a model to study diet-induced atherosclerosis

    Science.gov (United States)

    Golden-Syrian hamsters have been used as an animal model to assess diet-induced atherosclerosis since the early 1980s. Advantages appeared to include a low rate of endogenous cholesterol synthesis, receptor-mediated uptake of LDL cholesterol, cholesteryl ester transfer protein activity, hepatic apo...

  9. 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...

  10. Augmenting Chinese hamster genome assembly by identifying regions of high confidence.

    Science.gov (United States)

    Vishwanathan, Nandita; Bandyopadhyay, Arpan A; Fu, Hsu-Yuan; Sharma, Mohit; Johnson, Kathryn C; Mudge, Joann; Ramaraj, Thiruvarangan; Onsongo, Getiria; Silverstein, Kevin A T; Jacob, Nitya M; Le, Huong; Karypis, George; Hu, Wei-Shou

    2016-09-01

    Chinese hamster Ovary (CHO) cell lines are the dominant industrial workhorses for therapeutic recombinant protein production. The availability of genome sequence of Chinese hamster and CHO cells will spur further genome and RNA sequencing of producing cell lines. However, the mammalian genomes assembled using shot-gun sequencing data still contain regions of uncertain quality due to assembly errors. Identifying high confidence regions in the assembled genome will facilitate its use for cell engineering and genome engineering. We assembled two independent drafts of Chinese hamster genome by de novo assembly from shotgun sequencing reads and by re-scaffolding and gap-filling the draft genome from NCBI for improved scaffold lengths and gap fractions. We then used the two independent assemblies to identify high confidence regions using two different approaches. First, the two independent assemblies were compared at the sequence level to identify their consensus regions as "high confidence regions" which accounts for at least 78 % of the assembled genome. Further, a genome wide comparison of the Chinese hamster scaffolds with mouse chromosomes revealed scaffolds with large blocks of collinearity, which were also compiled as high-quality scaffolds. Genome scale collinearity was complemented with EST based synteny which also revealed conserved gene order compared to mouse. As cell line sequencing becomes more commonly practiced, the approaches reported here are useful for assessing the quality of assembly and potentially facilitate the engineering of cell lines. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. 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...

  12. 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...

  13. Effects of flavonol-rich diet on select cardiovascular parameters in a Gold Syrian Hamster model

    Science.gov (United States)

    We investigated the effects of a flavonoid-rich diet supplemented with cranberry on blood pressure and cholesterol ester levels in hypercholesterolemic Golden Syrian hamsters. Animals were fed one of four diets: high fat high cholesterol (HFHC) diet, HFHC with 2% cranberry concentrate powder (HFHC+...

  14. SRC family kinases in hamster spermatozoa: evidence for the presence of LCK.

    Science.gov (United States)

    Singh, Durgesh Kumar; Deshmukh, Rohit Kumar; Narayanan, Praveen Kumar; Shivaji, Sisinthy; Siva, Archana Bharadwaj

    2017-05-01

    Sperm capacitation is a prerequisite for successful fertilization. Increase in tyrosine phosphorylation is considered the hallmark of capacitation and attempts to understand its regulation are ongoing. In this regard, we attempted to study the role of SRC family kinases (SFKs) in the hamster sperm functions. Interestingly, we found the presence of the lymphocyte-specific protein tyrosine kinase, LCK, in mammalian spermatozoa and further characterized it in terms of its localization and function. LCK was found in spermatozoa of several species, and its transcript was identified in the hamster testis. Autophosphorylation of LCK at the Y394 residue increased as capacitation progressed, indicating an upregulation of LCK activity during capacitation. Inhibition of LCK (and perhaps the other SFKs) with the use of a specific inhibitor showed a significant decrease in protein tyrosine phosphorylation of several proteins, implying LCK/SFKs as key tyrosine kinase(s) regulating tyrosine phosphorylation during hamster sperm capacitation. Dihydrolipoamide dehydrogenase was identified as a substrate for LCK/SFK. LCK/SFKs inhibition significantly reduced the percentage fertilization ( in vitro ) but had no effect on sperm motility, hyperactivation and acrosome reaction. In summary, this is the first report on the presence of LCK, an SFK of hematopoietic lineage in spermatozoa besides being the first study on the role of SFKs in the spermatozoa of Syrian hamsters. © 2017 Society for Reproduction and Fertility.

  15. 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...

  16. The genetic audiogenic seizure hamster from Salamanca: The GASH:Sal.

    Science.gov (United States)

    Muñoz, Luis J; Carballosa-Gautam, Melissa M; Yanowsky, Kira; García-Atarés, Natividad; López, Dolores E

    2017-06-01

    The hamster has been previously described as a paroxysmal dystonia model, but our strain is currently recognized as a model of audiogenic seizures (AGS). The original first epileptic hamster appeared spontaneously at the University of Valladolid, where it was known as the GPG:Vall line, and was transferred to the University of Salamanca where a new strain was developed, named GASH:Sal. By testing auditory brainstem responses, the GASH:Sal exhibits elevated auditory thresholds that indicate a hearing impairment. Moreover, amplified fragment length polymorphism analysis distinguished genetic differences between the susceptible GASH:Sal hamster strain and the control Syrian hamsters. The GASH:Sal constitutes an experimental model of reflex epilepsy of audiogenic origin derived from an autosomal recessive disorder. Thus, the GASH:Sal exhibits generalized tonic-clonic seizures, characterized by a short latency period after auditory stimulation, followed by wild running, a convulsive phase, and finally stupor, with origin in the brainstem. The seizure profile of the GASH:Sal is similar to those exhibited by other models of inherited AGS susceptibility, which decreases after six months of age, but the proneness across generations is maintained. The GASH:Sal can be considered a reliable model of audiogenic seizures, suitable to investigate current antiepileptic pharmaceutical treatments as well as novel therapeutic drugs. This article is part of a Special Issue entitled "Genetic and Reflex Epilepsies, Audiogenic Seizures and Strains: From Experimental Models to the Clinic". Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Induction of atherosclerosis in mice and hamsters without germline genetic engineering

    DEFF Research Database (Denmark)

    Bjørklund, Martin Mæng; Hollensen, Anne Kruse; Hagensen, Mette Kallestrup

    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...

  18. 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...

  19. 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...

  20. Complete mitochondrial genome sequence of the heart failure model of cardiomyopathic Syrian hamster (Mesocricetus auratus).

    Science.gov (United States)

    Hu, Bo; Liu, Dong-Xing; Zhang, Yu-Qing; Song, Jian-Tao; Ji, Xian-Fei; Hou, Zhi-Qiang; Zhang, Zhen-Hai

    2016-05-01

    In this study we sequenced the complete mitochondrial genome sequencing of a heart failure model of cardiomyopathic Syrian hamster (Mesocricetus auratus) for the first time. The total length of the mitogenome was 16,267 bp. It harbored 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 non-coding control region.

  1. 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...

  2. Contractile and morphological properties of hamster retractor muscle following 16 h of cold preservation.

    NARCIS (Netherlands)

    de With, M.C.J.; Heijden, E.P.; van Oosterhout, M.F.M.; Kon, M.; Kroese, A.B.A.

    2009-01-01

    INTRODUCTION: Cold hypoxia is a common factor in cold tissue preservation and mammalian hibernation. The purpose of this study was to determine the effects of cold preservation on the function of the retractor (RET) muscle of the hamster in the non-hibernating state and compare these with previously

  3. Contractile and morphological properties of hamster retractor muscle following 16 h of cold preservation

    NARCIS (Netherlands)

    de With, Miriam C. J.; van der Heijden, E. P. A. Brigitte; van Oosterhout, Matthijs F.; Kon, M.; Kroese, Alfons B. A.

    2009-01-01

    Introduction: Cold hypoxia is a common factor in cold tissue preservation and mammalian hibernation. The purpose of this study was to determine the effects of cold preservation on the function of the retractor (RET) muscle of the hamster in the non-hibernating state and compare these with previously

  4. 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

  5. Effect of temperature on oxidative stress, antioxidant levels and uncoupling protein expression in striped hamsters.

    Science.gov (United States)

    Zhou, Si-Si; Cao, Li-Li; Xu, Wei-Dong; Cao, Jing; Zhao, Zhi-Jun

    2015-11-01

    According to the rate of living-free radical hypothesis, higher metabolic rates should increase reactive oxygen species (ROS) production. However, the "uncoupling to survive" hypothesis postulates that uncoupling proteins (UCPs) can decrease ROS production by lowering the potential of the inner mitochondrial membrane, in which case the correlation between metabolic rate and ROS levels would be a negative rather than positive. In this study, we examined energy intake, oxidative stress levels, antioxidant activity and the expression of UCPs in brown adipose tissue (BAT), and in the liver, heart, skeletal muscle and brain, of striped hamsters (Cricetulus barabensis) acclimated to either 5 °C or 32.5 °C. The energy intake of hamsters acclimated to 5 °C increased by 70.7%, whereas the energy intake of hamsters acclimated to 32.5 °C decreased by 31.3%, relative to hamsters kept at room temperature (21 °C) (Phamsters acclimated to 5 °C. These results suggest that the relationship between ROS levels and metabolic rate was negative, rather than positive. UCP1 expression in BAT may have played a role in lowering ROS levels. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Characterization of Spontaneous Mammary Tumors in Domestic Djungarian Hamsters (Phodopus sungorus).

    Science.gov (United States)

    Yoshimura, H; Kimura-Tsukada, N; Ono, Y; Michishita, M; Ohkusu-Tsukada, K; Matsuda, Y; Ishiwata, T; Takahashi, K

    2015-11-01

    Mammary tumors that spontaneously occurred in domestic Djungarian hamsters (Phodopus sungorus) were histologically examined. Forty-five mammary tumors included 14 adenomas, 18 adenocarcinomas, 1 lipid-rich carcinoma, 2 adenoacanthomas, 2 malignant adenomyoepitheliomas, 1 benign mixed tumor, and 7 "balloon cell" carcinosarcomas. The latter 4 types were newly recognized neoplasms in Djungarian hamsters. The relatively high incidence of spontaneous mammary carcinosarcomas in domestic Djungarian hamsters is intriguing. Carcinosarcomas exhibited anomalous histological features made up of a mixture of glandular cells, polygonal cells (including "balloon cells"), and sarcomatous spindle cells in varying proportions. Transitional features from glandular cells to polygonal cells and subsequently to sarcomatous spindle cells were observed. Using immunohistochemistry, we observed that glandular cells exhibited an epithelial phenotype (cytokeratin(+)/vimentin(-)), spindle cells exhibited a mesenchymal phenotype (cytokeratin(-)/vimentin(+)), and polygonal cells exhibited an intermediate phenotype (cytokeratin(+)/vimentin(+)). Reduction or loss of β-catenin expression and gain of S100A4 expression were observed in polygonal and spindle cells. The polygonal cell population included a varying number of characteristic cells that were expanded by large intracytoplasmic vacuoles. Electron microscopy revealed that these "balloon cells" had large cytoplasmic lumens lined by microvilli. These observations suggest that epithelial-mesenchymal transition may account for the pathogenesis of mammary carcinosarcomas in Djungarian hamsters. © The Author(s) 2015.

  7. Is the Medial Amygdala Part of the Neural Circuit Modulating Conditioned Defeat in Syrian Hamsters?

    Science.gov (United States)

    Markham, Chris M.; Huhman, Kim L.

    2008-01-01

    Conditioned defeat is a model wherein hamsters that have previously experienced a single social defeat subsequently exhibit heightened levels of avoidance and submission in response to a smaller, non-aggressive intruder. While we have previously demonstrated the critical involvement of the basolateral and central nuclei of the amygdala in the…

  8. EMODIN DOWNREGULATES CELL PROLIFERATION MARKERS DURING DMBA INDUCED ORAL CARCINOGENESIS IN GOLDEN SYRIAN HAMSTERS.

    Science.gov (United States)

    Manimaran, Asokan; Buddhan, Rajamanickam; Manoharan, Shanmugam

    2017-01-01

    Cell-cycle disruption is the major characteristic features of neoplastic transformation and the status of cell-cycle regulators can thus be utilized to assess the prognostic significance in patients with cancer. The PCNA, cyclin D1, CDK4, CDK6 and survivin expression in the buccal mucosa was utilized to evaluate the Emodin efficacy on abnormal cell proliferation during 7,12-dimethylbenz(a)anthracene (DMBA) induced oral carcinogenesis in golden Syrian hamsters. Topical application of DMBA, three times a week for 14 weeks, on the hamsters' buccal pouches developed well differentiated squamous cell carcinoma. Cyclin D1 and PCNA over-expression and up-regulation of CDK4, CDK6 and survivin were noticed in the buccal mucosa of hamsters treated with DMBA alone. Emodin administration (50mg/kg b.w) orally to hamsters treated with DMBA down-regulated the expression of cell proliferation markers in the buccal mucosa. The anti-cell proliferative role of Emodin is owing to its modulating efficacy on cell-cycle markers towards the tumor suppression during DMBA induced oral carcinogenesis.

  9. 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

  10. Conditioned flavor aversion and location avoidance in hamsters from toxic extract of tall larkspur (Delphinium barbeyi)

    Science.gov (United States)

    Studies were conducted to address conditioned flavour aversion (CFA) and place avoidance learning in hamsters given injections of alkaloid extracts from tall larkspur (Delphinium barbeyi), to determine if larkspur had reinforcing or negative properties sufficient to cause place avoidance or preferen...

  11. 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)

  12. Health Benefits of Dietary Tree Peony Seed Oil in a High Fat Diet Hamster Model

    National Research Council Canada - National Science Library

    Zhiqiang Zheng; Jigang Han; Yingyi Mao; Xue Tang; Yan Guan; Yonghong Hu

    2017-01-01

    .... In this study, we experimentally investigated benefits of dietary tree peony seed oil(PSO) in dyslipidemia-associated metabolic diseases using a high fat diet hamster model.Methods:High fat diets(HFD)containing 15 % coconut oil(CO...

  13. Calcium glucarate inhibits DMBA-induced oral carcinogenesis in the hamster: histomorphometric evaluation.

    Science.gov (United States)

    Lajolo, Carlo; Sgambato, Alessandro; Maiorano, Eugenio; Lucchese, Alberta; Capodiferro, Saverio; Favia, Gianfranco; Giuliani, Michele

    2010-03-01

    Calcium glucarate (CGT) is a promising chemopreventive agent. This study evaluated the in vivo efficacy of CGT in preventing 7,12-dimethylbenz(alpha) anthracene (DMBA)-induced oral carcinogenesis in the hamster. Matherials and Methods: Seventy-six Syrian hamsters were used, divided into four groups: group 1, untreated animals; 2, CGT controls; 3, DMBA-treated; 4, DMBA- and CGT-treated. Hamsters were painted three times weekly with 0.5% solution of DMBA and were fed a diet supplemented with CGT (64 mmol/kg, 2%). Animals were sacrificed at week 9 and 12 and pathology and histomorphometric analyses were performed. At week 9, four dysplastic lesions and six carcinomas were identified in group 3 while only three dysplasias and five carcinomas were detected in group 4. At week 12, five animals of group 3 displayed a dysplasia, which was only detected in one animal of group 4. Squamous carcinomas were identified in all animals of both group 3 and 4. However, in group 3 four of the animals displayed multifocal lesions and carcinomas displayed histological features indicative of increased aggressiveness. The results obtained suggest that CGT can exert an inhibitory effect on oral carcinogenesis in tha hamster and that further studies are warranted to evaluate its potential use as a chemopreventive agent in humans.

  14. 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

  15. Pharmacokinetics and pharmacodynamics of oleylphosphocholine in a hamster model of visceral leishmaniasis

    NARCIS (Netherlands)

    Fortin, Anny; Dorlo, Thomas P C; Hendrickx, Sarah; Maes, Louis

    OBJECTIVES: This study evaluated the pharmacokinetic properties of oleylphosphocholine (OlPC) in hamsters following a single oral dose. Its prophylactic activity was tested to establish exposure-activity relationships, while a 5 + 5 day oral regimen at 20 mg/kg with long post-treatment follow-up was

  16. 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.

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

    Science.gov (United States)

    Chakir, Ibtissam; Dumont, Stéphanie; Pévet, Paul; Ouarour, Ali; Challet, Etienne; Vuillez, Patrick

    2015-01-01

    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 (16 h light/08 h dark) or short photoperiods (08 h light/16 h 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.

  18. Anabolic-androgenic steroid exposure during adolescence and aggressive behavior in golden hamsters.

    Science.gov (United States)

    Melloni, R H; Connor, D F; Hang, P T; Harrison, R J; Ferris, C F

    1997-03-01

    Anabolic androgenic steroid (AAS) abuse by adolescents represents a significant health care risk due to the potential for long-term negative physical and psychological sequelae, including increased aggressive behavior. The current experiments examined the effects of AAS use in young male adolescent hamsters (Mesocricetus auratus) and their consequences on aggressive behavior. It was hypothesized that AAS administration during adolescence predisposes hamsters to heightened levels of aggressive behavior (i.e., offensive aggression). To test this hypothesis adolescent male hamsters were administered high doses of synthetic AAS to mimic a 'heavy use' self-administration regimen used by athletes. Immediately following the exposure to AAS hamsters were tested for aggressive behavior using a resident-intruder model. Animals treated with high doses of AAS during their adolescent development showed heightened measures of offensive aggression i.e., decreased latency to bite and increased total number of attacks and bites) during the test period, while measures of total activity (total contact time) between the animals remained unchanged. AAS-treated males did not differ in body weight from controls, suggesting that the increased aggression was not due to increased body mass. The results of this study show that exposure to AAS during adolescence facilitates aggressive response patterns, but does not alter body weight.

  19. Pathogenesis of a Phleboviral Infection (Punta Toro Virus) in Golden Syrian Hamsters

    Science.gov (United States)

    1990-04-01

    hamster model shares similarities to Rift Valley fever (phleboviral disease), which causes fatal disease in man and domesticated ruminants . ’Introduction...viral antigen was demonstrated in the platelet aggregates of the pancreas . Viral antigen was also seen in macro- phiages of the sinusoids of the

  20. 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...

  1. Agri-environmental schemes for the Common hamster (Cricetus cricetus). Why is the Dutch project Successful?

    NARCIS (Netherlands)

    Haye, la M.J.J.; Muskens, G.J.D.M.; Kats, van R.J.M.; Kuiters, A.T.; Siepel, H.

    2010-01-01

    The Common hamster (Cricetus cricetus) is a rodent, which inhabits arable land across Europe. Over the last decades, West European populations declined with more then 95%, which resulted in numerous local and regional extinctions. In the Netherlands the species went extinct in the wild in 2002, but

  2. 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

    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...

  3. Effect of dietary elaidic versus vaccenic acid on blood and liver lipids in the hamster

    NARCIS (Netherlands)

    G.W. Meijer (G.); A. van Tol (Arie); Th.J.C. van Berkel (Theo); J.T.M. Weststrate

    2001-01-01

    textabstractMale hamsters (30 per group) were fed five different semi-purified diets ad libitum. The diets, containing 30% of energy (en%) as fat, differed in their dietary fat composition (specified fatty acids exchanged at 10 en%) and were fed for 4 weeks. The five fatty acids compared in mixed

  4. Reversible remodeling of lung tissue during hibernation in the Syrian hamster

    NARCIS (Netherlands)

    Talaei, Fatemeh; Hylkema, Machteld N.; Bouma, Hjalmar R.; Boerema, Ate S.; Strijkstra, Arjen M.; Henning, Rob H.; Schmidt, Martina

    During hibernation, small rodents such as hamsters cycle through phases of strongly suppressed metabolism with low body temperature (torpor) and full restoration of metabolism and body temperature (arousal). Remarkably, the repetitive stress of cooling-rewarming and hypoxia does not cause

  5. 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

  6. Albino and pink-eyed dilution mutants in the Russian dwarf hamster Phodopus campbelli.

    Science.gov (United States)

    Robinson, R

    1996-01-01

    The coat color mutant genes albino (c) and pink eyed dilution (p) are described in the dwarf hamster species Phodopus campbelli. Both genes are inherited as redessive to normal. Tests for linkage between the two genes gave negative results. The apparent absence of linkage is contrasted with linkage between homologous alleles c and p in other species of rodents.

  7. Cardiovascular protection of deep-seawater drinking water in high-fat/cholesterol fed hamsters.

    Science.gov (United States)

    Hsu, Chin-Lin; Chang, Yuan-Yen; Chiu, Chih-Hsien; Yang, Kuo-Tai; Wang, Yu; Fu, Shih-Guei; Chen, Yi-Chen

    2011-08-01

    Cardiovascular protection of deep-seawater (DSW) drinking water was assessed using high-fat/cholesterol-fed hamsters in this study. All hamsters were fed a high-fat/cholesterol diet (12% fat/0.2% cholesterol), and drinking solutions were normal distiled water (NDW, hardness: 2.48ppm), DSW300 (hardness: 324.5ppm), DSW900 (hardness: 858.5ppm), and DSW1500 (hardness: 1569.0ppm), respectively. After a 6-week feeding period, body weight, heart rates, and blood pressures of hamsters were not influenced by DSW drinking waters. Serum total cholesterol (TC), triacylglycerol (TAG), atherogenic index, and malondialdehyde (MDA) levels were decreased (pdrinking-water groups, as compared to those in the NDW group. Additionally, increased (pdrinking-water groups. Hepatic low-density-lipoprotein receptor (LDL receptor) and cholesterol-7α-hydroxylase (CYP7A1) gene expressions were upregulated (pdrinking waters. These results demonstrate that DSW drinking water benefits the attenuation of high-fat/cholesterol-diet-induced cardiovascular disorders in hamsters. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. 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.

  9. Quantitative ultrastructural changes induced by sucrose administration in the pancreatic B cells of normal hamsters.

    Science.gov (United States)

    Camihort, G; Del Zotto, H; Gómez Dumm, C L; Gagliardino, J J

    2000-04-01

    We have previously reported that young male Syrian hamsters receiving a sucrose-rich diet presented increased B-cell replication rate and size. The aim of the present study was to analyze, under the same experimental conditions, the ultrastructural changes in B cells. For this purpose, young male Syrian hamsters were fed with a commercial diet and 10% sucrose in their drinking water (S group) while the control group (C) received the same diet and tap water, for 5 weeks. Samples of the pancreas removed after that period were processed for the immunohistochemical identification of B cells as well as for measuring several ultrastructural parameters. S hamsters showed higher serum insulin levels, while similar serum glucose values were obtained in animals from both groups. The B cells from S group exhibited lesser number of dense secretory granules at expenses of an increase of the pale ones, increased number of both exocytosis profiles and fusion-granule images, as well as enlargement of the intercellular space and mitochondrial area. Marked expansions of this space, limited by junctional complexes, were observed between adjacent B cells. These results would indicate that sucrose administration to normal hamsters not only increases the pancreatic B-cell mass but also induces measurable subcellular changes in the individual B-cell characteristic of an enhanced secretory activity. The present model would represent a useful tool for testing strategies in preventing the damage or promoting the recovery of the pancreatic B cells.

  10. Seismic Anisotropy Beneath the Eastern Flank of the Rio Grande Rift

    Science.gov (United States)

    Benton, N. W.; Pulliam, J.

    2015-12-01

    Shear wave splitting was measured across the eastern flank of the Rio Grande Rift (RGR) to investigate mechanisms of upper mantle anisotropy. Earthquakes recorded at epicentral distances of 90°-130° from EarthScope Transportable Array (TA) and SIEDCAR (SC) broadband seismic stations were examined comprehensively, via the Matlab program "Splitlab", to determine whether SKS and SKKS phases indicated anisotropic properties. Splitlab allows waveforms to be rotated, filtered, and windowed interactively and splitting measurements are made on a user-specified waveform segment via three independent methods simultaneously. To improve signal-to-noise and improve reliability, we stacked the error surfaces that resulted from grid searches in the measurements for each station location. Fast polarization directions near the Rio Grande Rift tend to be sub-parallel to the RGR but then change to angles that are consistent with North America's average plate motion, to the east. The surface erosional depression of the Pecos Valley coincides with fast polarization directions that are aligned in a more northerly direction than their neighbors, whereas the topographic high to the east coincides with an easterly change of the fast axis.The area above a mantle high velocity anomaly discovered separately via seismic tomography which may indicate thickened lithosphere, corresponds to unusually large delay times and fast polarization directions that are more closely aligned to a north-south orientation. The area of southeastern New Mexico that falls between the mantle fast anomaly and the Great Plains craton displays dramatically smaller delay times, as well as changes in fast axis directions toward the northeast. Changes in fast axis directions may indicate flow around the mantle anomaly; small delay times could indicate vertical or attenuated flow.

  11. Cloning and characterization of the 5'-flanking region of the pig AgRP gene.

    Science.gov (United States)

    Ling, Fei; Wang, Tao; Wei, Liqiong; Zhu, Xiaoping; Chen, Yaosheng; Li, Jiaqi; Zhang, Zongwu; Du, Hongli; Wang, Xiaoning; Wang, Jufang

    2011-04-01

    Agouti-related peptide (AgRP), a brain neuropeptide generated by AgRP/neuropeptide Y (NPY) neurons, plays a vital role in the hypothalamic regulation of energy homeostasis. RT-PCR and real-time PCR were carried out in various tissues to detect the AgRP expression pattern in pigs. Our RT-PCR results showed that the pig AgRP gene was ubiquitously expressed in all examined tissues including heart, liver, spleen, lung, kidney, stomach, bladder, m. longissimus, belly fat, brain, large intestine, lymph, back fat, skin, and hypothalamus. Real-time quantitative PCR experiments revealed that it is in the hypothalamus with the highest expression of AgRP both in adult Lantang and Landrace pigs compared to the back fat and m.longissimus muscle and the cDNA level of AgRP in the hypothalamus of adult Chinese indigenous Lantang pig (fat-type) is significantly higher than that of Landrace pig (lean-type). To understand the regulation of the pig AgRP gene, the 5'-flanking region was isolated from a pig bacterial artificial chromosome library and used in a luciferase reporter assay. A positive cis-acting element for efficient AgRP expression was identified at nucleotides -501 to -479, by 5'-serial deletion of the promoter. Electrophoretic mobility-shift assays (EMSA) with competing oligonucleotides revealed that the critical region contained a cis-acting element for Neurogenic Differentiation (NeuroD), which is a member of the NeuroD family of basic-helix-loop-helix transcription factors. This element has not been reported in human or mouse AgRP genes. Our results indicated that NeuroD might be an essential regulatory factor for transcription of pig AgRP, providing an important clue about energy homeostasis regulation in the porcine and human brain.

  12. Morphostructural development of the Eritrean rift flank (southern Red Sea) inferred from apatite fission track analysis

    Science.gov (United States)

    Abbate, Ernesto; Balestrieri, Maria Laura; Bigazzi, Giulio

    2002-11-01

    The Red Sea is one of the best exposed young rift basins in the world. Its flanks on both the African and Arabian sides are characterized by basement uplifts parallel to the margins and by active erosion. Through the integration of 37 new apatite fission track (FT) analyses and regional geology, we elucidate the uplift and denudational history of the Eritrean continental margin along the southern Red Sea and, in particular, the development, timing, and past and present morphostructural features of its onshore portion. FT data indicate that at around 20 Ma, the Eritrean margin was affected by a crustal cooling event due to a postrifting accelerated phase of denudation. This cooling has the same age as those already detected on the conjugate Arabian margin (Yemen and Saudi Arabia). FT ages increase from 10-20 to 300-400 Ma with increasing distance and elevation from the coastal areas toward the interior. This trend indicates a diminishing amount of eroded section in the same direction. We use FT and structural data to define the position of the main border fault along the margin where the original scarp was located. We estimate rates of vertical denudation of 190-200 m/Myr at the border fault and of ≤60-70 m/Myr on the plateau. On the basis of these new data, we argue against an Oligocene tectonic unroofing of the margin through a low-angle detachment assumed by previous authors, but we maintain the essential role of the erosional denudation in the development of present margin morphology.

  13. Temperature and redox effect on mineral colonization in Juan de Fuca Ridge flank subsurface crustal fluids

    Directory of Open Access Journals (Sweden)

    Jean-Paul eBaquiran

    2016-03-01

    Full Text Available To examine microbe-mineral interactions in subsurface oceanic crust, we evaluated microbial colonization on crustal minerals that were incubated in borehole fluids for one year at the seafloor wellhead of a crustal borehole observatory (IODP Hole U1301A, Juan de Fuca Ridge flank as compared to an experiment that was not exposed to subsurface crustal fluids (at nearby IODP Hole U1301B. In comparison to previous studies at these same sites, this approach allowed assessment of the effects of temperature, fluid chemistry, and/or mineralogy on colonization patterns of different mineral substrates, and an opportunity to verify the approach of deploying colonization experiments at an observatory wellhead at the seafloor instead of within the borehole. The Hole U1301B deployment did not have biofilm growth, based on microscopy and DNA extraction, thereby confirming the integrity of the colonization design against bottom seawater intrusion. In contrast, the Hole U1301A deployment supported biofilms dominated by Epsilonproteobacteria (43.5% of 370 16S rRNA gene clone sequences and Gammaproteobacteria (29.3%. Sequence analysis revealed overlap in microbial communities between different minerals incubated at the Hole U1301A wellhead, indicating that mineralogy did not separate biofilm structure within the one-year colonization experiment. Differences in the Hole U1301A wellhead biofilm community composition relative to previous studies from within the borehole using similar mineral substrates suggest that temperature and the diffusion of dissolved oxygen through plastic components influenced the mineral colonization experiments positioned at the wellhead. This highlights the capacity of low abundance crustal fluid taxa to rapidly establish communities on diverse mineral substrates under changing environmental conditions such as from temperature and oxygen.

  14. Cost analysis of different protocols for imaging a patient with acute flank pain.

    Science.gov (United States)

    Grisi, G; Stacul, F; Cuttin, R; Rimondini, A; Meduri, S; Dalla Palma, L

    2000-01-01

    The aim of this study was to analyse the costs of different diagnostic approaches to patients with acute flank pain. Four different diagnostic approaches were considered: (a) spiral CT without contrast medium (CM); (b) plain film, ultrasonography (US) and intravenous urography (IVU)--the latter procedure is used in our department in cases still unsolved following the former investigations (28% in our experience); (c) plain film, US and spiral CT without CM (as an alternative to IVU in 28% of cases); and (d) IVU. The cost of each procedure in a university hospital was calculated, following analysis of the differential costs of each investigation (equipment, depreciation and maintenance costs, related materials and services, radiologists, radiographers, nurses) and their common costs (auxiliary personnel and indirect internal costs). Finally, we calculated the full cost of each procedure and applied it to the different diagnostic approaches. The full cost of each approach was: (a) spiral CT without CM = 74 Euro; (b) plain film, US and IVU (28%) = 66.89 Euro; (c) plain film, US and spiral CT without CM (28%) = 64.93 Euro; (d) IVU = 80.90 Euro. Intravenous urography alone or in unsolved cases is not to be considered because it provides higher costs and worse diagnostic results, whereas X-ray dose to patient is almost equal between IVU and spiral CT. Spiral CT integrated to plain film and US in unsolved cases could be preferred because of lower cost and dose to patient, though reaching a diagnostic conclusion may take longer than an immediate spiral CT.

  15. A coarse-grained model for polyglutamine aggregation modulated by amphipathic flanking sequences.

    Science.gov (United States)

    Ruff, Kiersten M; Khan, Siddique J; Pappu, Rohit V

    2014-09-02

    The aggregation of proteins with expanded polyglutamine (polyQ) tracts is directly relevant to the formation of neuronal intranuclear inclusions in Huntington's disease. In vitro studies have uncovered the effects of flanking sequences as modulators of the driving forces and mechanisms of polyQ aggregation in sequence segments associated with HD. Specifically, a seventeen-residue amphipathic stretch (N17) that is directly N-terminal to the polyQ tract in huntingtin decreases the overall solubility, destabilizes nonfibrillar aggregates, and accelerates fibril formation. Published results from atomistic simulations showed that the N17 module reduces the frequency of intermolecular association. Our reanalysis of these simulation results demonstrates that the N17 module also reduces interchain entanglements between polyQ domains. These two effects, which are observed on the smallest lengthscales, are incorporated into phenomenological pair potentials and used in coarse-grained Brownian dynamics simulations to investigate their impact on large-scale aggregation. We analyze the results from Brownian dynamics simulations using the framework of diffusion-limited cluster aggregation. When entanglements prevail, which is true in the absence of N17, small spherical clusters and large linear aggregates form on distinct timescales, in accord with in vitro experiments. Conversely, when entanglements are quenched and a barrier to intermolecular associations is introduced, both of which are attributable to N17, the timescales for forming small species and large linear aggregates become similar. Therefore, the combination of a reduction of interchain entanglements through homopolymeric polyQ and barriers to intermolecular associations appears to be sufficient for providing a minimalist phenomenological rationalization of in vitro observations regarding the effects of N17 on polyQ aggregation. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  16. A porous flow model of flank eruptions on Mt. Etna: second-order perturbation theory

    Directory of Open Access Journals (Sweden)

    N. Cenni

    1997-06-01

    Full Text Available A porous flow model for magma migration from a deep source within a volcanic edifice is developed. The model is based on the assumption that an isotropic and homogeneous system of fractures allows magma migration from one localized feeding dyke up to the surface of the volcano. The maximum level that magma can reach within the volcano (i.e., the «free surface» of magma, where fluid pressure equals the atmospheric pressure is reproduced through a second-order perturbation approach to the non-linear equations governing the migration of incompressible fluids through a porous medium. The perturbation parameter is found to depend on the ratio of the volumic discharge rate at the source (m3/s divided by the product of the hydraulic conductivity of the medium (m1/s times the square of the source depth. The second-order corrections for the free surface of Mt. Etna are found to be small but not negligible; from the comparison between first-order and second-order free surfaces it appears that the former is higher near the summit, slightly lower at intermediate altitudes and slightly higher far away from the axis of the volcano. Flank eruptions in the southern sector are found to be located in regions where the topography is actually lower than the theoretical free surface of magma. In this sector, modulations in the eruption site density correlate well with even minor differences between free surface and topography. In the northern and western sectors similar good fits are found, while the NE rift and the eastern sector seem to require mechanisms or structures respectively favouring and inhibiting magma migration.

  17. Sunward propagating Pc5 waves observed on the post-midnight magnetospheric flank

    Directory of Open Access Journals (Sweden)

    P. T. I. Eriksson

    2008-06-01

    Full Text Available The overall focus on the driver of toroidal Pc5 waves has been on processes located at or acting on the dayside magnetopause and dayside flanks of the magnetosphere. These processes can generate waves that propagate tailward in the magnetosphere. However, an increasing number of studies, both theoretical and experimental, have looked at waves propagating sunward and that are caused by processes in the magnetotail. Here we present an ultra low frequency (ULF wave observed in the post-midnight/morning sector of the magnetosphere at L=16 RE. The wave has a toroidal mode polarization. We estimate the azimuthal wave number to m=3, consistent with a toroidal mode type pulsation. The positive sign indicates that the wave is propagating sunward and this is confirmed by looking at the Poynting flux of the wave. The frequency of the wave is not constant with time but shows a small increase in the beginning of the event up to over 2.0 mHz. Then the frequency decreases to 1.0 mHz. This decrease coincides with a drop in the total magnetic field strength and we speculate if this is related to an observed reversal of the sign of the interplanetary magnetic field (IMF By-component. This event occurs during relatively quiet magnetospheric conditions with a solar wind speed of approximately 400 km/s. Thus this event is highly likely to be driven by a source in the magnetotail and the change in frequency is an excellent example that the frequency of an ULF wave may be modulated by changes of the plasma parameters on the resonant field line.

  18. Persistent changes of corticostriatal plasticity in dt(sz) mutant hamsters after age-dependent remission of dystonia.

    Science.gov (United States)

    Avchalumov, Y; Volkmann, C E; Rückborn, K; Hamann, M; Kirschstein, T; Richter, A; Köhling, R

    2013-10-10

    Abnormal plasticity in the cortico-basal ganglia-thalamocortical loop has been suggested to represent a key factor in the pathophysiology of dystonia. In a model of primary paroxysmal dystonia, the dt(sz) mutant hamster, previous experiments have shown a strongly increased long-term potentiation (LTP) in comparison to non-dystonic control hamsters. These basal changes, i.e. in the absence of dystonia, were found in young animals at an age of 5 weeks, when the age-dependent dystonia in dt(sz) mutant reaches highest severity. In the present study we examined in corticostriatal slices (1) whether the increases in synaptic plasticity can be modulated by stressful stimuli which induce dystonic episodes in young mutant hamsters, and (2) whether increases of LTP persist after spontaneous remission of dystonia in animals older than 10 weeks. The present data show that in slices of young mutant hamsters the extent of LTP was not influenced by the presence of dystonia: In comparison to age-matched control hamsters, LTP was increased in mutant hamsters independent of preceding stressful stimulation. After remission of dystonia, i.e., in older dt(sz) mutant hamsters >10 weeks, only LTP could be elicited, while in preparations from age-matched control hamsters, either LTP or long-term depression developed, depending on previous behavioral challenge. We conclude that in mature brain, corticostriatal connections have the potential for changes in metaplasticity, while in dt(sz) mutant hamsters this metaplasticity is persistently infringed even though stress-inducible dystonic symptoms are lost. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. Proteomic mapping of the lung vascular endothelial cell surface in Schistosoma bovis-infected hamsters.

    Science.gov (United States)

    de la Torre-Escudero, Eduardo; Pérez-Sánchez, Ricardo; Manzano-Román, Raúl; Oleaga, Ana

    2014-06-25

    Schistosomes are blood trematodes that are perfectly adapted to living in their intravascular habitat and to achieve this they have developed mechanisms enabling them to evade the immune and haemostatic responses of the host and to regulate endothelial cell function to favour their own survival. The objective of this work was to analyse the changes induced by Schistosoma bovis schistosomula in the proteome expressed by infected hamsters, over 10 and 20 days, on the endothelial surface of their pulmonary vasculature. To accomplish this, we subjected the lungs of non-infected and S. bovis-infected hamsters to vascular perfusion with a biotin ester reactive. Analysis by liquid chromatography and tandem mass spectrometry analysis (LC-MS/MS) of endothelial surface proteins resulted in the identification of a total of 459 non-redundant proteins in the lung vasculature of infected and non-infected hamsters. Here we report the proteins identified, classified according to their biological function and cellular location, further analysing the differences in lung vascular proteomes between non-infected and S. bovis-infected hamsters for ten and twenty days. This work provides the first data on the vascular surface proteome of the lung after S. bovis infection and identifies some of the changes induced in it during infection. To identify the changes induced by schistosomula larvae of Schistosoma bovis in the proteome of the pulmonary vasculature of the host, we compared the proteins expressed on the vascular endothelium of the lungs of non-infected and infected hamsters over 10 and 20 days. Mass spectrometry analysis (LC-MS/MS) of the proteins isolated from the vascular endothelium resulted in the identification of a total of 459 non-redundant proteins in the lung of infected and non-infected hamsters. The proteins identified are classified according to their biological function and cellular location, further analysing the differences in lung vascular proteomes between non

  20. Use of the Syrian Hamster as a New Model of Ebola Virus Disease and Other Viral Hemorrhagic Fevers

    Directory of Open Access Journals (Sweden)

    Hideki Ebihara

    2012-12-01

    Full Text Available Historically, mice and guinea pigs have been the rodent models of choice for therapeutic and prophylactic countermeasure testing against Ebola virus disease (EVD. Recently, hamsters have emerged as a novel animal model for the in vivo study of EVD. In this review, we discuss the history of the hamster as a research laboratory animal, as well as current benefits and challenges of this model. Availability of immunological reagents is addressed. Salient features of EVD in hamsters, including relevant pathology and coagulation parameters, are compared directly with the mouse, guinea pig and nonhuman primate models.

  1. 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.

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

    Directory of Open Access Journals (Sweden)

    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. Separate origin of the main components of the left coronary artery in Syrian hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Durán, A C; Arqué, J M; Fernández, B; Fernández, M C; Fernández-Gallego, T; Sans-Coma, V

    2007-08-01

    This study describes a rare congenital coronary artery anomaly in the Syrian hamster; namely, the separate origin of the obtuse marginal and left circumflex arteries which are the main components of the left coronary artery. The hearts of nine affected animals were examined by means of a corrosion-cast technique and histology. The hamsters belonged to a laboratory inbred family with a high incidence of coronary artery anomalies and bicuspid aortic valve. The aortic valve was tricuspid in three hamsters and bicuspid in the other six hamsters. In all cases, the right coronary artery was normal, whereas the left coronary artery main trunk was absent. The present anomalous coronary artery patterns could be classified into two main entities: (i) ectopic origin of the obtuse marginal artery from the right aortic sinus or from the right coronary artery, with the left circumflex artery arising from the left side of the aortic valve; and (ii) ectopic origin of both the obtuse marginal artery from the right aortic sinus or from the right coronary artery and left circumflex artery from the dorsal aortic sinus. In all cases, the obtuse marginal artery coursed to the right side of the heart through the ventral wall of the right ventricular outflow tract. When the left circumflex artery arose from the dorsal aortic sinus, it formed an acute angle with the aortic wall. This report seems to be the first to describe the separate origin of the main components of the left coronary artery in a non-human mammalian species. In man, the congenital coronary artery and aortic valve defects reported herein may entail the risk of clinical complications. However, none of the affected hamsters showed signs of disease.

  4. Equivalent pore radius and velocity of elastic waves in shale. Skjold Flank-1 Well, Danish North Sea

    DEFF Research Database (Denmark)

    Mbia, Ernest Ncha; Fabricius, Ida Lykke; Oji, Collins O.

    2013-01-01

    logging data.We used cuttings samples and available well logs to characterize Cenozoic, Cretaceous and Jurassic shale sections in the Skjold Flank-1 well of Danish North Sea. Logging data and well reports were used to select 31 shale cuttings samples and experimental data for porosity, grain density...... relationships were used to calculate equivalent pore radius for the Cenozoic, Cretaceous and Jurassic shale sections in Skjold Flank-1 well from elastic moduli. Elastic moduli were calculated from sonic velocity and density logs. The calculated equivalent pore radius logs vary from 27nm at 500m to 13nm at 2000m...... experiments on cuttings or core samples. In this study we demonstrate that elastic moduli as calculated from bulk density and velocity of elastic waves relate to equivalent pore radius of the studied shale intervals. This relationship establishes the possibility of calculating equivalent pore radius from...

  5. Variants within the 5'-flanking regions of bovine milk protein genes: I. κ-casein-encoding gene.

    Science.gov (United States)

    Schild, T A; Wagner, V; Geldermann, H

    1994-09-01

    In order to identify DNA variants within the 5'-flanking region of the bovine κ-casein (κCn)-encoding gene, this area of the gene from 13 cows belonging to seven breeds (Holstein Friesian, Brown Swiss, German Simmental, Jersey, Galloway, Scottish Highland and Ceylon Dwarf Zebu) was analysed. For each individual, about 1 kb of the 5'-flanking region including exon I was amplified by polymerase chain reaction (PCR). The biotinylated PCR product was immobilized on magnetic beads followed by direct bidirectional sequencing using an automated DNA sequencer. Fifteen DNA variants were identified, some of which are located within potential regulatory sites and possibly involved in the expression of the κ-casein encoding gene.

  6. AMPLITUDES OF DISJUNCTIVE DISLOCATIONS IN THE KNIPOVICH RIDGE FLANKS (NORTHERN ATLANTIC AS AN INDICATOR OF MODERN REGIONAL GEODYNAMICS

    Directory of Open Access Journals (Sweden)

    S. Yu. Sokolov

    2017-01-01

    Full Text Available This article presents the first map showing the vertical amplitudes of modern disjunctive dislocations inNorthern Atlantic, based on the estimated phase shifts of reflected waves recorded by high-frequency seismic acoustic surveys. The amplitude distribution pattern is mosaic with alternating areas of compression and extension in the flanks of the Knipovich rift system. The modern structure of the Knipovich Ridge, including two strike-slip faults, represents a local rift in the pull-apart setting. The asymmetry of stresses and the presence of compression in the ridge flanks is evidenced by the distribution of the focal mechanisms of strong earthquakes related to reverse faults. In the southeastern Knipovich Ridge, tectonic activity is marked by the asymmetric pattern of the epicenters of small earthquakes.

  7. Preliminary assessment of the state of CO2 soil degassing on the flanks of Gede volcano (West Java, Indonesia)

    Science.gov (United States)

    Kunrat, S. L.; Schwandner, F. M.

    2013-12-01

    Gede Volcano (West Java) is part of an andesitic stratovolcano complex consisting of Pangrango in the north-west and Gede in the south-east. The last recorded eruptive activity was a phreatic subvolcanian ash eruption in 1957. Current activity is characterized by episodic swarms at 2-4 km depth, and low-temperature (~160°C) crater degassing in two distinct summit crater fumarolic areas. Hot springs occur in the saddle between the Gede and Pangrango edifice, as well as on the NE flank base. The most recent eruptive events produced pyroclastic material, their flow deposits concentrate toward the NE. A collaborative effort between the Center for Volcanology and Geological Hazard Mitigation (CVGHM), Geological Agency and the Earth Observatory of Singapore (EOS) is since 2010 aimed at upgrading the geophysical and geochemical monitoring network at Gede Volcano. To support the monitoring instrumentation upgrades under way, surveys of soil CO2 degassing have been performed on the flanks of Gede, in circular and radial traverses.The goal was to establish a spatial distribution of flank CO2 fluxes, and to allow smart siting for continuous gas monitoring stations. Crater fluxes were not surveyed, as its low-temperature hydrothermal system is likely prone to large hydraulic changes in this tropical environment, resulting in variable permeability effects that might mask signals from deeper reservoir or conduit degassing. The high precipitation intensity in the mountains of tropical Java pose challenges to this method, since soil gas permeability is largely controlled by soil moisture content. Simultaneous soil moisture measurements were undertaken. The soil CO2 surveys were carried out using a LI-8100A campaign flux chamber instrument (LICOR Biosciences, Lincoln, Nebraska). This instrument has a very precise and highly stable sensor and an atmospheric pressure equilibrator, making it highly sensitive to low fluxes. It is the far superior choice for higher precision low

  8. Imaging modalities and therapy options in patients with acute flank pain; Bildgebungsmodalitaeten und Therapieoptionen bei Patienten mit akutem Flankenschmerz

    Energy Technology Data Exchange (ETDEWEB)

    Grosse, A.; Grosse, C. [Universitaet Bern, Bern (Switzerland)

    2014-07-15

    The objective of this article is the description of imaging techniques for the evaluation of patients with acute flank pain and suspicion of urolithiasis and the impact of these techniques in the therapy management of patients with calculi. (orig.) [German] Ziel der Arbeit ist die Eroerterung der bildgebenden Verfahren zur Abklaerung von Patienten mit akutem Flankenschmerz und Verdacht auf Urolithiasis und die Rolle dieser Verfahren im Therapiemanagement von Steinpatienten. (orig.)

  9. The spectrum of persistent volcanic flank instability: A review and proposed framework based on Kīlauea, Piton de la Fournaise, and Etna

    Science.gov (United States)

    Poland, Michael; Peltier, Aline; Bonaforte, Alessandro; Puglisi, Giuseppe

    2017-01-01

    Persistent motion of the south flank of Kīlauea Volcano, Hawai'i, has been known for several decades, but has only recently been identified at other large basaltic volcanoes—namely Piton de la Fournaise (La Réunion) and Etna (Sicily)—thanks to the advent of space geodetic techniques. Nevertheless, understanding of long-term flank instability is based largely on the example of Kīlauea, despite the large differences in the manifestations and mechanisms of the process when viewed through a comparative lens. For example, the rate of flank motion at Kīlauea is several times that of Etna and Piton de la Fournaise and is accommodated on a slip plane several km deeper than is probably present at the other two volcanoes. Gravitational spreading also appears to be the dominant driving force at Kīlauea, given the long-term steady motion of the volcano's south flank regardless of eruptive/intrusive activity, whereas magmatic activity plays a larger role in flank deformation at Etna and Piton de la Fournaise. Kīlauea and Etna, however, are both characterized by heavily faulted flanks, while Piton de la Fournaise shows little evidence for flank faulting. A helpful means of understanding the spectrum of persistent flank motion at large basaltic edifices may be through a framework defined on one hand by magmatic activity (which encompasses both magma supply and edifice size), and on the other hand by the structural setting of the volcano (especially the characteristics of the subvolcanic basement or subhorizontal intravolcanic weak zones). A volcano's size and magmatic activity will dictate the extent to which gravitational and magmatic forces can drive motion of an unstable flank (and possibly the level of faulting of that flank), while the volcano's structural setting governs whether or not a plane of weakness exists beneath or within the edifice and can facilitate flank slip. Considering persistent flank instability using this conceptual model is an alternative to

  10. Compartmentalization of the Coso East Flank geothermal field imaged by 3-D full-tensor MT inversion

    Science.gov (United States)

    Lindsey, Nathaniel J.; Kaven, Joern; Davatzes, Nicholas C.; Newman, Gregory A.

    2017-01-01

    Previous magnetotelluric (MT) studies of the high-temperature Coso geothermal system in California identified a subvertical feature of low resistivity (2–5 Ohm m) and appreciable lateral extent (>1 km) in the producing zone of the East Flank field. However, these models could not reproduce gross 3-D effects in the recorded data. We perform 3-D full-tensor inversion and retrieve a resistivity model that out-performs previous 2-D and 3-D off-diagonal models in terms of its fit to the complete 3-D MT data set as well as the degree of modelling bias. Inclusion of secondary Zxx and Zyy data components leads to a robust east-dip (60†) to the previously identified conductive East Flank reservoir feature, which correlates strongly with recently mapped surface faults, downhole well temperatures, 3-D seismic reflection data, and local microseismicity. We perform synthetic forward modelling to test the best-fit dip of this conductor using the response at a nearby MT station. We interpret the dipping conductor as a fractured and fluidized compartment, which is structurally controlled by an unmapped blind East Flank fault zone.

  11. Cloning of Genomic DNA Flanking Transposon in the Nonpathogenic Mutant of Xanthomonas axonopodis pv. glycines M715

    Directory of Open Access Journals (Sweden)

    ALINA AKHDIYA RUSMANA

    2005-06-01

    Full Text Available The objective of this work is to clone flanking DNA derived from Tn-5 mutagenesis of wild type strain Xanthomonas axonopodis pv. glycines as first step to clone and to identify the gene involved in pathogenicity mechanism. We have localized the flanking DNA fragment from a nonpathogenic mutant of Xag M715. Southern hybridization analysis using 2.8 kb EcoRI from pYR103 as a probe showed that the fragment is located within 2.0 kb PstI fragment. A 0.7 kb flanking DNA was amplified using inverse PCR technique, and inserted into pGEM-T Easy vector generating a 3.7 kb recombinant plasmid (pAA01. Southern hybridization analysis of the wild type (YR32 with pAA01 as a probe indicated a hybridization signal located at approximately 3.0 kb PstI fragment. DNA sequence analysis revealed that the DNA fragment has a 64% identity to a vir gene of Bacillus anthracis.

  12. Ups and downs on spreading flanks of ocean-island volcanoes: evidence from Mauna Loa and Kīlauea

    Science.gov (United States)

    Lipman, Peter W.; Eakins, Barry W.; Yokose, Hisayoshi

    2003-01-01

    Submarine-flank deposits of Hawaiian volcanoes are widely recognized to have formed largely by gravitationally driven volcano spreading and associated landsliding. Observations from submersibles show that prominent benches at middepths on flanks of Mauna Loa and Kilauea consist of volcaniclastic debris derived by landsliding from nearby shallow submarine and subaerial flanks of the same edifice. Massive slide breccias from the mature subaerial tholeiitic shield of Mauna Loa underlie the frontal scarp of its South Kona bench. In contrast, coarse volcaniclastic sediments derived largely from submarine-erupted preshield alkalic and transitional basalts of ancestral Kilauea underlie its Hilina bench. Both midslope benches record the same general processes of slope failure, followed by modest compression during continued volcano spreading, even though they record development during different stages of edifice growth. The dive results suggest that volcaniclastic rocks at the north end of the Kona bench, interpreted by others as distal sediments from older volcanoes that were offscraped, uplifted, and accreted to the island by far-traveled thrusts, alternatively are a largely coherent stratigraphic assemblage deposited in a basin behind the South Kona bench.

  13. Comparative analysis and interobserver variation of unenhanced computed tomography and intravenous urography in the diagnosis of acute flank pain.

    Science.gov (United States)

    Ben Nakhi, Abdelmohsen; Gupta, Renu; Al-Hunayan, Adel; Muttikkal, Thomas; Chavan, Venu; Mohammed, Ahmed; Ali, Yusuf

    2010-01-01

    The purpose of this study was to compare unenhanced computed tomography (UECT) to intravenous urography (IVU) for detecting urinary tract calculi, signs of obstruction and non-renal causes in the assessment of acute flank pain, and in their interobserver agreement. In this prospective study, carried out at a university hospital over a period of 1 year, 36 patients (27 males and 9 females) participated. Mean age was 44 +/- 15 years (range: 14-73 years). The patients presented with acute flank pain and underwent UECT and IVU. The images were blindly evaluated by 2 experienced radiologists and the two techniques compared using the two-tailed McNemar's test for matched pairs; p values IVU found them in only 8 (22.2%). The increased detection by UECT was due to its ability to detect smaller stones (IVU in determining calculus position, in detecting primary or secondary signs of obstruction and in identifying non-urinary causes of flank pain. The overall average of agreement, as indicated by kappa values, was 0.88 for UECT and 0.61 for IVU. UECT showed better detectability and interobserver agreement tan IVU, suggesting that UECT could replace IVU as the first imaging modality in the evaluation of acute renal colic. Copyright 2010 S. Karger AG, Basel.

  14. Long-range genomic enrichment, sequencing, and assembly to determine unknown sequences flanking a known microRNA.

    Directory of Open Access Journals (Sweden)

    Zhaorong Ma

    Full Text Available Conserved plant microRNAs (miRNAs modulate important biological processes but little is known about conserved cis-regulatory elements (CREs surrounding MIRNA genes. We developed a solution-based targeted genomic enrichment methodology to capture, enrich, and sequence flanking genomic regions surrounding conserved MIRNA genes with a locked-nucleic acid (LNA-modified, biotinylated probe complementary to the mature miRNA sequence. Genomic DNA bound by the probe is captured by streptavidin-coated magnetic beads, amplified, sequenced and assembled de novo to obtain genomic DNA sequences flanking MIRNA locus of interest. We demonstrate the sensitivity and specificity of this enrichment methodology in Arabidopsis thaliana to enrich targeted regions spanning 10-20 kb surrounding known MIR166 and MIR165 loci. Assembly of the sequencing reads successfully recovered all targeted loci. While further optimization for larger, more complex genomes is needed, this method may enable determination of flanking genomic DNA sequence surrounding a known core (like a conserved mature miRNA from multiple species that currently don't have a full genome assembly available.

  15. Mutation of the Sp1 binding site in the 5' flanking region of SRY causes sex reversal in rabbits.

    Science.gov (United States)

    Song, Yuning; Liu, Tingjun; Wang, Yong; Deng, Jichao; Chen, Mao; Yuan, Lin; Lu, Yi; Xu, Yuxin; Yao, Haobin; Li, Zhanjun; Lai, Liangxue

    2017-06-13

    Sex-determining region Y is a crucial gene that initiates male sex determination in mammals. Mutations of the Sp1-binding site in the 5' flanking region of SRY are associated with clinical male-to-female sex reversal syndrome, although such occurrences are rare and, until now, have not been reported in animal models. In this study, we mutated Sp1-binding sites in the 5' flanking region of the rabbit SRY gene using the CRISPR/Cas9 system. As expected, the SRY-Sp1 knockout rabbits had female external and internal genitalia and exhibited normal female copulatory behaviors, but they were infertile, and the adults displayed reduced follicles. Interestingly, we successfully obtained offspring from sex-reversed SRY-Sp1 knockout rabbits using embryo transfer. In summary, our study demonstrates that Sp1 is a major regulator in SRY gene transcription, and mutations of the Sp1 binding sites (Sp1-B and Sp1-C) in the 5' flanking region of SRY induce sex reversal in rabbits, which can be used as targets for clinical research of male-to-female sex reversal syndrome. Additionally, we provide the first evidence that sex reversal syndrome patients have the potential to become pregnant with the use of embryo transfer.

  16. Mutation of the Sp1 binding site in the 5′ flanking region of SRY causes sex reversal in rabbits

    Science.gov (United States)

    Wang, Yong; Deng, Jichao; Chen, Mao; Yuan, Lin; Lu, Yi; Xu, Yuxin; Yao, Haobin; Li, Zhanjun; Lai, Liangxue

    2017-01-01

    Sex-determining region Y is a crucial gene that initiates male sex determination in mammals. Mutations of the Sp1-binding site in the 5′ flanking region of SRY are associated with clinical male-to-female sex reversal syndrome, although such occurrences are rare and, until now, have not been reported in animal models. In this study, we mutated Sp1-binding sites in the 5′ flanking region of the rabbit SRY gene using the CRISPR/Cas9 system. As expected, the SRY-Sp1 knockout rabbits had female external and internal genitalia and exhibited normal female copulatory behaviors, but they were infertile, and the adults displayed reduced follicles. Interestingly, we successfully obtained offspring from sex-reversed SRY-Sp1 knockout rabbits using embryo transfer. In summary, our study demonstrates that Sp1 is a major regulator in SRY gene transcription, and mutations of the Sp1 binding sites (Sp1-B and Sp1-C) in the 5′ flanking region of SRY induce sex reversal in rabbits, which can be used as targets for clinical research of male-to-female sex reversal syndrome. Additionally, we provide the first evidence that sex reversal syndrome patients have the potential to become pregnant with the use of embryo transfer. PMID:28445127

  17. Scanning mutagenesis of the amino acid sequences flanking phosphorylation site 1 of the mitochondrial pyruvate dehydrogenase complex

    Directory of Open Access Journals (Sweden)

    Nagib eAhsan

    2012-07-01

    Full Text Available The mitochondrial pyruvate dehydrogenase complex is regulated by reversible seryl-phosphorylation of the E1α subunit by a dedicated, intrinsic kinase. The phospho-complex is reactivated when dephosphorylated by an intrinsic PP2C-type protein phosphatase. Both the position of the phosphorylated Ser-residue and the sequences of the flanking amino acids are highly conserved. We have used the synthetic peptide-based kinase client assay plus recombinant pyruvate dehydrogenase E1α and E1α-kinase to perform scanning mutagenesis of the residues flanking the site of phosphorylation. Consistent with the results from phylogenetic analysis of the flanking sequences, the direct peptide-based kinase assays tolerated very few changes. Even conservative changes such as Leu, Ile, or Val for Met, or Glu for Asp, gave very marked reductions in phosphorylation. Overall the results indicate that regulation of the mitochondrial pyruvate dehydrogenase complex by reversible phosphorylation is an extreme example of multiple, interdependent instances of co-evolution.

  18. Crystal structure and functional characterization of the human RBM25 PWI domain and its flanking basic region.

    Science.gov (United States)

    Gong, Deshun; Yang, Fan; Li, Fudong; Qian, Dandan; Wu, Minhao; Shao, Zhenhua; Wu, Mian; Wu, Jihui; Shi, Yunyu

    2013-02-15

    Human RBM25 (RNA-binding motif protein 25) is a novel splicing factor that contains a PWI domain, a newly identified RNA/DNA-binding domain, and regulates Bcl-x pre-mRNA alternative splicing. The flanking basic region has been suggested to serve as a co-operative partner of the PWI domain in the binding of nucleic acids, but the structure of this basic region is unknown. In the present paper, we report the crystal structure of the RBM25 PWI domain and its flanking basic region. The PWI domain is revealed to comprise a conserved four-helix bundle, and the flanking basic region forms two α-helices and associates with helix H4 of the PWI domain. These interactions promote directly the formation of an enlarged nucleic-acid-binding platform. Structure-guided mutagenesis reveals a positively charged nucleic-acid-binding surface in the RBM25 PWI domain that is entirely different from that in the SRm160 PWI domain. Furthermore, we show that the promotion of the pro-apoptotic Bcl-xS isoform expression by RBM25 is facilitated by the PWI domain in vivo. Thus the present study suggests that the PWI domain plays an important role in the regulation of Bcl-x pre-mRNA alternative splicing.

  19. Adhesive and migratory effects of phosphophoryn are modulated by flanking peptides of the integrin binding motif.

    Directory of Open Access Journals (Sweden)

    Shigeki Suzuki

    Full Text Available Phosphophoryn (PP is generated from the proteolytic cleavage of dentin sialophosphoprotein (DSPP. Gene duplications in the ancestor dentin matrix protein-1 (DMP-1 genomic sequence created the DSPP gene in toothed animals. PP and DMP-1 are phosphorylated extracellular matrix proteins that belong to the family of small integrin-binding ligand N-linked glycoproteins (SIBLINGs. Many SIBLING members have been shown to evoke various cell responses through the integrin-binding Arg-Gly-Asp (RGD domain; however, the RGD-dependent function of PP is not yet fully understood. We demonstrated that recombinant PP did not exhibit any obvious cell adhesion ability, whereas the simultaneously purified recombinant DMP-1 did. A cell adhesion inhibitory analysis was performed by pre-incubating human osteosarcoma MG63 cells with various PP peptides before seeding onto vitronectin. The results obtained revealed that the incorporation of more than one amino acid on both sides of the PP-RGD domain was unable to inhibit the adhesion of MG63 cells onto vitronectin. Furthermore, the inhibitory activity of a peptide containing the PP-RGD domain with an open carboxyl-terminal side (H-463SDESDTNSESANESGSRGDA482-OH was more potent than that of a peptide containing the RGD domain with an open amino-terminal side (H-478SRGDASYTSDESSDDDNDSDSH499-OH. This phenomenon was supported by the potent cell adhesion and migration abilities of the recombinant truncated PP, which terminated with Ala482. Furthermore, various point mutations in Ala482 and/or Ser483 converted recombinant PP into cell-adhesive proteins. Therefore, we concluded that the Ala482-Ser483 flanking sequence, which was detected in primates and mice, was the key peptide bond that allowed the PP-RGD domain to be sequestered. The differential abilities of PP and DMP-1 to act on integrin imply that DSPP was duplicated from DMP-1 to serve as a crucial extracellular protein for tooth development rather than as an integrin

  20. The Syrian Golden Hamster Estrous Cycle: Unique Characteristics, Visual Guide to Staging, and Comparison with the Rat.

    Science.gov (United States)

    Chanut, Franck J A; Williams, Ann M

    2016-01-01

    The Syrian hamster, Mesocricetus auratus, is a suitable rodent species for standard regulatory toxicity studies. However, little is published about the female Syrian hamster reproductive system. It has unique anatomic features that differ from the other rodent species. In the hamster, the upper cervix is composed of 2 canals and the vagina shows 2 lateral pouches where keratin debris accumulates. These pouches must be distinguished from the vagina in order to stage the estrous cycle properly. The microscopic changes occurring during all the estrous cycle stages show some differences with the other rodents, the lower cervix and upper vagina presenting the more dramatic changes. The aim of this work was to produce a practical guide to staging the cycle and to highlight some of the differences between the rat and hamster reproductive system. © The Author(s) 2015.

  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. Augmentation of sebaceous lipogenesis by an ethanol extract of Grifola frondosa (Maitake mushroom) in hamsters in vivo and in vitro.

    Science.gov (United States)

    Nagao, Mie; Sato, Takashi; Akimoto, Noriko; Kato, Yuya; Takahashi, Masao; Ito, Akira

    2009-08-01

    Grifola frondosa (Maitake mushroom) is an edible and medicinal mushroom with versatile effects such as antitumor and immunomodulating actions. Here, we demonstrated that an ethanol extract of G. frondosa fruiting body (Maitake extract) augmented intracellular lipid droplet formation and the production of triacylglycerols (TG), a major component of sebum, along with the activation of diacylglycerol acyltransferase, a rate-limiting enzyme of TG synthesis in cultured hamster sebocytes. The topical treatment of Maitake extract on the skin of hamster auricles augmented sebum accumulation in sebaceous glands and ducts. However, in comparison with the Maitake extract, another ethanol extract prepared from Agaricus blazei Murill showed less activity in sebaceous lipogenesis in hamsters in vivo and in vitro. These results provide novel evidence that Maitake extract augments sebaceous lipogenesis in hamsters in vivo and in vitro. Thus, Maitake extract is likely to be a unique agent leading to the remission of dry skin.

  4. Heat flow, morphology, pore fluids and hydrothermal circulation in a typical Mid-Atlantic Ridge flank near Oceanographer Fracture Zone

    Science.gov (United States)

    Le Gal, V.; Lucazeau, F.; Cannat, M.; Poort, J.; Monnin, C.; Battani, A.; Fontaine, F.; Goutorbe, B.; Rolandone, F.; Poitou, C.; Blanc-Valleron, M.-M.; Piedade, A.; Hipólito, A.

    2018-01-01

    Hydrothermal circulation affects heat and mass transfers in the oceanic lithosphere, not only at the ridge axis but also on their flanks, where the magnitude of this process has been related to sediment blanket and seamounts density. This was documented in several areas of the Pacific Ocean by heat flow measurements and pore water analysis. However, as the morphology of Atlantic and Indian ridge flanks is generally rougher than in the Pacific, these regions of slow and ultra-slow accretion may be affected by hydrothermal processes of different regimes. We carried out a survey of two regions on the eastern and western flanks of the Mid-Atlantic Ridge between Oceanographer and Hayes fracture zones. Two hundred and eight new heat flow measurements were obtained along six seismic profiles, on 5 to 14 Ma old seafloor. Thirty sediment cores (from which porewaters have been extracted) have been collected with a Kullenberg corer equipped with thermistors thus allowing simultaneous heat flow measurement. Most heat flow values are lower than those predicted by purely conductive cooling models, with some local variations and exceptions: heat flow values on the eastern flank of the study area are more variable than on the western flank, where they tend to increase westward as the sedimentary cover in the basins becomes thicker and more continuous. Heat flow is also higher, on average, on the northern sides of both the western and eastern field regions and includes values close to conductive predictions near the Oceanographer Fracture Zone. All the sediment porewaters have a chemical composition similar to that of bottom seawater (no anomaly linked to fluid circulation has been detected). Heat flow values and pore fluid compositions are consistent with fluid circulation in volcanic rocks below the sediment. The short distances between seamounts and short fluid pathways explain that fluids flowing in the basaltic aquifer below the sediment have remained cool and unaltered

  5. Identification and functional analysis of variant haplotypes in the 5'-flanking region of protein phosphatase 2A-Bδ gene.

    Directory of Open Access Journals (Sweden)

    Hui-Feng Chen

    Full Text Available Serine-threonine protein phosphatase 2A (PP2A is a trimeric holoenzyme that plays an integral role in the regulation of cell growth, differentiation, and apoptosis. The substrate specificity and (subcellular localization of the PP2A holoenzymes are highly regulated by interaction with a family of regulatory B subunits (PP2A-Bs. The regulatory subunit PP2A-B/PR55δ (PP2A-Bδ is involving in the dephosphorylation of PP2A substrates and is crucial for controlling entry into and exit from mitosis. The molecular mechanisms involved in the regulation of expression of PP2A-Bδ gene (PPP2R2D remain largely unknown. To explore genetic variations in the 5'-flanking region of PPP2R2D gene as well as their frequent haplotypes in the Han Chinese population and determine whether such variations have an impact on transcriptional activity, DNA samples were collected from 70 healthy Chinese donors and sequenced for identifying genetic variants in the 5'-flanking region of PPP2R2D. Four genetic variants were identified in the 1836 bp 5'-flanking region of PPP2R2D. Linkage disequilibrium (LD patterns and haplotype profiles were constructed for the genetic variants. Using serially truncated human PPP2R2D promoter luciferase constructs, we found that a 601 bp (-540 nt to +61 nt fragment constitutes the core promoter region. The subcloning of individual 5'-flanking fragment revealed the existence of three haplotypes in the distal promoter of PPP2R2D. The luciferase reporter assay showed that different haplotypes exhibited distinct promoter activities. The EMSA revealed that the -462 G>A variant influences DNA-protein interactions involving the nuclear factor 1 (NF1. In vitro reporter gene assay indicated that cotransfection of NF1/B expression plasmid could positively regulate the activity of PPP2R2D proximal promoter. Introduction of exogenous NF1/B expression plasmid further confirmed that the NF1 involves in the regulation of PPP2R2D gene expression. Our findings

  6. Investigating the potential for volcano flank instability triggered by recent dike intrusions at Fogo volcano, Cape Verde

    Science.gov (United States)

    Bagnardi, Marco; González, Pablo; Hooper, Andrew; Wright, Tim

    2015-04-01

    Gravitational flank-collapses at volcanoes are rare but catastrophic events that have rarely been witnessed by humans (e.g., Mount St. Helens in 1980). It has been proposed that gravitationally unstable volcanic flanks can be classified in two different types based on the flanks slope: volcanoes characterized by gentle slopes (Hawaiian-like) and that have very dynamic flanks exhibiting high rates of deformation and, conversely, steep-sided volcanoes (Macaronesian-like) showing minimal ground deformation. The two types of volcanoes could therefore reach the stable-state through different mechanisms and experience different mass-wasting processes. Numerous giant debris-avalanche deposits have been identified offshore the volcanoes of the Canary Islands and Cape Verde. Given the steep slopes of these volcanoes, the mass-wasting events may have occurred suddenly and with minimal precursory signals. Several mechanisms have been proposed as potential triggers and among these the intrusion of shallow dikes feeding fissure eruptions is one of the best candidates. In this work, we investigate this hypothesis in the light of new and revised results derived from the analysis of geodetic observations at Fogo volcano (Cape Verde). Fogo has erupted twice in the last 20 years (1995 and 2014-2015) and in both occasions the volcano erupted along fissures that seem to be fed by dykes intruding the shallow crust and the volcanic edifice. We re-process radar data from the ERS satellite to obtain state-of-the-art deformation maps spanning the 1995 eruption and revisit previously proposed models of the magmatic system. Our results indicate that both eruptions were fed by sub-vertical dikes, steeply dipping to the SE, and radiating from the Pico do Fogo volcanic cone to the SW. We also study the effect of such magmatic intrusions in terms of the stress regime that they generate and analyze whether the 1995 and 2014 intrusions could potentially destabilize the structures along which a

  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. Hydrogen gas attenuates embryonic gene expression and prevents left ventricular remodeling induced by intermittent hypoxia in cardiomyopathic hamsters.

    Science.gov (United States)

    Kato, Ryuji; Nomura, Atsuo; Sakamoto, Aiji; Yasuda, Yuki; Amatani, Koyuha; Nagai, Sayuri; Sen, Yoko; Ijiri, Yoshio; Okada, Yoshikatsu; Yamaguchi, Takehiro; Izumi, Yasukatsu; Yoshiyama, Minoru; Tanaka, Kazuhiko; Hayashi, Tetsuya

    2014-12-01

    The prevalence of sleep apnea is very high in patients with heart failure (HF). The aims of this study were to investigate the influence of intermittent hypoxia (IH) on the failing heart and to evaluate the antioxidant effect of hydrogen gas. Normal male Syrian hamsters (n = 22) and cardiomyopathic (CM) hamsters (n = 33) were exposed to IH (repeated cycles of 1.5 min of 5% oxygen and 5 min of 21% oxygen for 8 h during the daytime) or normoxia for 14 days. Hydrogen gas (3.05 vol/100 vol) was inhaled by some CM hamsters during hypoxia. IH increased the ratio of early diastolic mitral inflow velocity to mitral annulus velocity (E/e', 21.8 vs. 16.9) but did not affect the LV ejection fraction (EF) in normal Syrian hamsters. However, IH increased E/e' (29.4 vs. 21.5) and significantly decreased the EF (37.2 vs. 47.2%) in CM hamsters. IH also increased the cardiomyocyte cross-sectional area (672 vs. 443 μm(2)) and interstitial fibrosis (29.9 vs. 9.6%), along with elevation of oxidative stress and superoxide production in the left ventricular (LV) myocardium. Furthermore, IH significantly increased the expression of brain natriuretic peptide, β-myosin heavy chain, c-fos, and c-jun mRNA in CM hamsters. Hydrogen gas inhalation significantly decreased both oxidative stress and embryonic gene expression, thus preserving cardiac function in CM hamsters. In conclusion, IH accelerated LV remodeling in CM hamsters, at least partly by increasing oxidative stress in the failing heart. These findings might explain the poor prognosis of patients with HF and sleep apnea. Copyright © 2014 the American Physiological Society.

  9. 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...

  10. Efek Antihiperglikemik Dan Antihiperkolesterol Ekstrak Tempe Kacang Komak (Lablab Purpureus (L.) Sweet) Pada Hamster Diabetik Diet Tinggi Kolesterol

    OpenAIRE

    Wardani, Elly; Wahyudi, Priyo; Dewi, Karina Rosinta; Setiawan, Rojid

    2015-01-01

    Kacang komak (Lablab purpureus (L.) Sweet) mengandung senyawa aktif yang memiliki aktivitas sebagai antihiperglikemik dan antihiperkolesterol. Penelitian ini bertujuan untuk mengetahui efek ekstrak tempe kacang komak terhadap kadar glukosa darah, kolesterol total, dan LDL darah hamster yang diinduksi aloksan dan pakan tinggi kolesterol. Hewan uji hamster Syrian jantan dibagi 7 kelompok perlakuan. Dosis uji yang digunakan yaitu 280 mg/kg BB, 560 mg/kg BB, dan 1120 mg/kg BB secara peroral selam...

  11. A comparison of liver protein changes in mice and hamsters treated with the peroxisome proliferator Wy-14,643.

    Energy Technology Data Exchange (ETDEWEB)

    Giometti, C. S.; Tollaksen, S. L.; Cunningham, M. L.; Center for Mechanistic Biology and Biotechnology; National Inst. of Environmental Health Sciences

    1998-01-01

    Interspecies differences in the liver response to Wy-14,643, a potent peroxisome proliferator in rats and mice, have been demonstrated. While both rats and mice show dramatic increases in the number of peroxisomes, the activity of peroxisomal enzymes involved in the {beta}-oxidation of fatty acids, and heptocyte replication, Syrian hamsters have a more moderate peroxisome proliferation response and no sustained increase in cell replication. Rats and mice, but not hamsters, develop hepatocellular carcinoma after prolonged exposure to Wy-14,643. To further characterize this species difference, two-dimensional gel electrophoresis (2-DE) has been used to compare the effect of 14-day exposure to various dietary concentrations of Wy-14,643 on liver protein expression in male mice and hamsters. Digitized images of the 2-DE protein maps were searched for significant changes. The peroxisome bifunctional enzyme (PBE) enoyl CoA hydratase/3-hydroxyacyl dehydrogenase, which migrates to the same position in mouse and hamster liver protein 2-DE patterns, increased in abundance by more than three times the control level in both mice and hamsters. In addition to the quantitative change in PBE, significant quantitative changes (P < 0.001) were found in 49 mouse liver proteins (47 decreasing and 2 increasing) and in 35 hamster liver proteins (27 decreasing and 8 increasing). There was little overlap in the mouse and hamster proteins showing quantitative changes in response to Wy-14,643, with the exception of PBE and one unidentified liver protein with an approximate molecular weight of 50 000. These results show that although peroxisome proliferation occurs in the livers of both mice and hamsters exposed to Wy-14,643, other species-specific changes in proteins occur that are independent of the peroxisome proliferation response and that could be related to species-specific susceptibility or resistance to liver tumor induction.

  12. 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.

  13. Effect of acetone administration on renal, pulmonary and hepatic monooxygenase activities in hamster.

    Science.gov (United States)

    Menicagli, S; Puccini, P; Longo, V; Gervasi, P G

    1990-11-01

    Administration of acetone in drinking water to Syrian Golden hamsters for 9-10 days altered microsomal P-450 dependent monooxygenase activities in the liver and the kidney but not in the lung. While hepatic microsomal NADPH-cytochrome c reductase was unaffected, cytochrome b5 and P-450 content increased (about 100%) in liver but not in kidney. Furthermore acetone treatment resulted in an increase of microsomal reverse type I binding with DMSO and in an increase in the P-450IIE1-linked renal and hepatic activities such as aniline hydroxylase (AnH) and p-nitrophenol hydroxylase (pNPH). The SDS-PAGE analysis confirmed the induction in acetone-treated microsomes of a hepatic protein with the M.W. of ethanol inducible P-450IIE1 of hamster. The acetone treatment however, unlike ethanol, induced other activities such as benzphetamine N-demethylase and ethoxycoumarin O-deethylase in liver and aminopyrine N-demethylase in kidney. No change of ethoxyresorufin O-deethylase and pentoxyresorufin O-depentylase was observed in either renal or hepatic microsomes. Addition of acetone in vitro had an inhibitory effect on pNPH by hepatic microsomes from control or acetone induced hamsters, while AnH was not affected. Interruption of acetone administration for 24 h resulted in a return of AnH and pNPH activities to essentially basal levels in the liver suggesting a rapid turnover of the hamster P-450IIE1 (ham P-450j). Our results indicate that, as found in rat, acetone is a good inducer of the P-450IIE1 (ham P-450j) in hamster in both the liver and kidney. However other P-450 forms, such as, probably, the renal and hepatic P-450IIB1, are also induced. Thus acetone-treated hamsters, which, in certain respects, show a qualitatively different induction pattern from that reported for ethanol, can be used as an useful animal model to study the toxicity of certain xenobiotics.

  14. Genetically alike Syrian hamsters display both bifoliate and trifoliate aortic valves.

    Science.gov (United States)

    Sans-Coma, Valentín; Carmen Fernández, M; Fernández, Borja; Durán, Ana C; Anderson, Robert H; Arqué, Josep M

    2012-01-01

    The bifoliate, or bicuspid, aortic valve (BAV) is the most frequent congenital cardiac anomaly in man. It is a heritable defect, but its mode of inheritance remains unclear. Previous studies in Syrian hamsters showed that BAVs with fusion of the right and left coronary leaflets are expressions of a trait, the variation of which takes the form of a phenotypic continuum. It ranges from a trifoliate valve with no fusion of the coronary leaflets to a bifoliate root devoid of any raphe. The intermediate stages are represented by trifoliate valves with fusion of the coronary aortic leaflets, and bifoliate valves with raphes. The aim of this study was to elucidate whether the distinct morphological variants rely on a common genotype, or on different genotypes. We examined the aortic valves from 1 849 Syrian hamsters belonging to a family subjected to systematic inbreeding by full-sib mating. The incidence of the different trifoliate aortic valve (TAV) and bifoliate aortic valve (BAV) morphological variants widely varied in the successive inbred generations. TAVs with extensive fusion of the leaflets, and BAVs, accounted for five-sixths of the patterns found in Syrian hamsters considered to be genetically alike or virtually isogenic, with the probability of homozygosity being 0.999 or higher. The remaining one-sixth hamsters had aortic valves with a tricuspid design, but in most cases the right and left coronary leaflets were slightly fused. Results of crosses between genetically alike hamsters, with the probability of homozygosity being 0.989 or higher, revealed no significant association between the valvar phenotypes in the parents and their offspring. Our findings are consistent with the notion that the BAVs of the Syrian hamster are expressions of a quantitative trait subject to polygenic inheritance. They suggest that the genotype of the virtually isogenic animals produced by systematic inbreeding greatly predisposes to the development of anomalous valves, be they

  15. Molecular aspects of neoplasia of Syrian hamster cells transformed in vitro by chemical carcinogens.

    Science.gov (United States)

    Notario, V; DiPaolo, J A

    1998-08-01

    The addition of environmental agents (carcinogens) induces transformation that can be quantitated. Its frequency follows a linear relationship with dose and is consistent with a 'one hit' phenomenon. Transformed colonies produce transformed lines with attributes of neoplastic cells including production of tumors. The results parallel in vivo activity. Although, molecular analysis of most animal assay indicate the presence of activated oncogenes belonging to the ras family, ras activation is a low frequency event in the neoplastic conversion of Syrian hamster cells just as is found with human malignancies. In our analysis of 22 independently derived lines N-ras activation was found only with sodium bisulfite transformed lines. A novel oncogene named carcinogenesis promotion hamster (cph) because its association with the carcinogenic process has been identified. This resulted from focusing on Syrian hamster cells transformed with a single dose of 3-methylcholanthrene (MCA) and cosmid-rescue-techniques from a third-cycle NIH3T3 transformant obtained by sequential transfections of genomic DNA from MCA-initiated hamster fetal cells. cph transforms NIH3T3 cells and acts synergistically with Ha-ras to transform murine fibroblasts. Gene expression analysis using cph genomic fragments from normal and neoplastic cells identifies a number of transcripts including a major mRNA of 2.5 kb as well as several larger transcripts. cph is actively transcribed in different tissues and different species. In the hamster it is a single copy gene localized by FISH to the euchromatic short arm of the X chromosome, at region Xpa7. cph does not have any significant global homology to sequences deposited in date banks, confirming that it is a novel gene. The transforming gene codes for a truncated 246 amino acids whereas the normal cph has a residue of 469 amino acids. In conclusion cph oncogene is activated by a single point-mutation; its activation appears an important mechanism for the

  16. 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...

  17. Identification of Reference Genes for Quantitative Real Time PCR Assays in Aortic Tissue of Syrian Hamsters with Bicuspid Aortic Valve.

    Science.gov (United States)

    Rueda-Martínez, Carmen; Fernández, M Carmen; Soto-Navarrete, María Teresa; Jiménez-Navarro, Manuel; Durán, Ana Carmen; Fernández, Borja

    2016-01-01

    Bicuspid aortic valve (BAV) is the most frequent congenital cardiac malformation in humans, and appears frequently associated with dilatation of the ascending aorta. This association is likely the result of a common aetiology. Currently, a Syrian hamster strain with a relatively high (∼40%) incidence of BAV constitutes the only spontaneous animal model of BAV disease. The characterization of molecular alterations in the aorta of hamsters with BAV may serve to identify pathophysiological mechanisms and molecular markers of disease in humans. In this report, we evaluate the expression of ten candidate reference genes in aortic tissue of hamsters in order to identify housekeeping genes for normalization using quantitative real time PCR (RT-qPCR) assays. A total of 51 adult (180-240 days old) and 56 old (300-440 days old) animals were used. They belonged to a control strain of hamsters with normal, tricuspid aortic valve (TAV; n = 30), or to the affected strain of hamsters with TAV (n = 45) or BAV (n = 32). The expression stability of the candidate reference genes was determined by RT-qPCR using three statistical algorithms, GeNorm, NormFinder and Bestkeeper. The expression analyses showed that the most stable reference genes for the three algorithms employed were Cdkn1β, G3pdh and Polr2a. We propose the use of Cdkn1β, or both Cdkn1β and G3pdh as reference genes for mRNA expression analyses in Syrian hamster aorta.

  18. 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.

  19. Effect of shanzha, a Chinese herbal product, on obesity and dyslipidemia in hamsters receiving high-fat diet.

    Science.gov (United States)

    Kuo, Daih-Huang; Yeh, Ching-Hua; Shieh, Po-Chuen; Cheng, Kai-Chun; Chen, Fu-An; Cheng, Juei-Tang

    2009-07-30

    The present study is designed to investigate the effect of shanzha (Crataegus pinnatifida) on obesity or dyslipidemia induced by high-fat diet in hamsters and characterize the role of PPARalpha in this action of shanzha. We induced dyslipidemia and obesity in hamsters using high-fat diet and treated hamsters with shanzha or vehicle for 7 days. We measured the body weight, adipose tissue weights, and food intake of hamsters. Plasma total cholesterol (TC), triglyceride (TG), LDL-cholesterol (LDL-C) and HDL-cholesterol (HDL-C) were determined at the beginning and end of this treatment. Effect of shanzha on adipogenesis was examined in vitro and change of PPARalpha was analyzed using Western blot. The food intake, body weights, and weights of both brown and white adipose tissues were markedly reduced in hamsters receiving shanzha as compared with the vehicle-treated control. Plasma levels of TC, TG and LDL-C were decreased by this shanzha treatment while HDL-C was elevated. The effects of shanzha were reversed by the combined treatment with PPARalpha antagonist, MK886. Shanzha inhibited the fat droplet accumulation in 3T3-L1 adipocytes in a dose-dependent manner and this effect was abolished by MK886. Western blot results showed activation of PPARalpha by shanzha in hamster adipose tissue. We suggest that shanzha could activate PPARalpha to improve dyslipidemia or obesity.

  20. Efficiency of the oral, intramuscular and subcutaneous routes for the experimental infection of hamster and sheep with Schistosoma bovis.

    Science.gov (United States)

    Oleaga, Ana; Ramajo, Vicente

    2004-09-20

    The percutaneous administration of cercariae is the usual method for experimental infections with Schistosoma bovis. These procedures are laborious and have important inconveniences when working with a large number of animals, especially if they are ruminants. In the present study, the efficiency of the oral, intramuscular and subcutaneous routes are evaluated by comparison with the percutaneous route in experimental infections with S. bovis. The infections developed in hamsters and sheep were evaluated taking as a basis the parasite burden, the concentrations of eggs in tissues and the levels of anti-Schistosoma antibodies. The oral infection failed in both hamsters and sheep. The administration of the cercariae by the intramuscular route was effective in sheep, developing infections of intensity similar to that of the infections acquired percutaneously. In hamsters, on the contrary, although all the animals developed the infection, they were very little intense. The injection of the cercariae by the subcutaneous route induces acceptable infections in hamsters and can also be an alternative route to percutaneous exposure. The levels of the anti-Schistosoma bovis antibodies detected in hamster and sheep were proportional to the number of worms present, which shows that the humoral response is a good indicator of the intensity of the infections. It can be concluded that the intramuscular route is a good alternative to the percutaneous route for experimental infections of sheep with S. bovis. Likewise, the subcutaneous route can also substitute, with some advantages, the percutaneous infections in hamsters.