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Sample records for gerbil meriones unguiculatus

  1. The electroretinogram of Mongolian gerbil (Meriones unguiculatus): comparison to mouse.

    PubMed

    Yang, Shengyan; Luo, Xiaopeng; Xiong, Guoyin; So, Kwok-Fai; Yang, Hui; Xu, Ying

    2015-03-01

    The Mongolian gerbil (Meriones unguiculatus) is a diurnal rodent whose retinal photoreceptors comprise 13% cones in contrast to 1-3% in nocturnal mice and rats. Moreover, it displays a retinal structure more analogous to that of human than of mouse. However, the electroretinogram (ERG) recordings of gerbils have not yet been well studied. Thus, here we compared the ERGs of gerbils and C57 mice. We recorded responses to full-field flashes of increasing intensities under both dark and light adaptation. We also investigated responses to flickers of increasing frequencies and to long-duration flashes under photopic conditions. In scotopic, the amplitudes of the gerbil a- and b-waves are slightly smaller than those of the mouse waves. However, in photopic, the gerbil wave amplitudes are 2-fold larger than those of mice. Gerbils also exhibit larger flicker responses and higher flicker fusion frequencies than mice. Furthermore, unlike mice, gerbils show a positive OFF response (d-wave) and a post b-wave positive potential (i-wave), features commonly observed in human photopic ERGs. Our results suggest that gerbils may complement rod-dominant mice as models for studying retinal cone function and pathologies. PMID:25578951

  2. Spontaneous lesions and parasites of the Mongolian gerbil, Meriones unguiculatus.

    PubMed

    Vincent, A L; Porter, D D; Ash, L R

    1975-12-01

    Four-hundred-eighty Mongolian gerbils, Meriones unguiculatus [Uclp:(MON)], most of which were experimentally infected with filarial worms, were examined for spontaneous lesions. Previously unrecognized lesions included cutaneous squamous cell carcinoma, duodenal adenocarcinoma, malignant blue nevus, hepatic choleangiocarcinoma, malignant hemangiopericytoma of the uterus, ovarian teratoma, chronic interstitial nephritis, renal cortical retention cysts, splenic hemangiomas, and various histologic abnormalities of the lung. Previously reported lesions also seen in the present study were a malignant melanoma, adrenal cortical adenoma or carcinoma, uterine leiomyoma, sebaceous gland adenoma, hepatic lymphangioma, and renal hemangioma. Hymenolepis diminuta (Cestoda) and Tyrophagus castellani (Acarina) were accidentally recovered from experimental animals. Tritichomonas caviae and a species of Entamoeba were the most common intestinal protozoa. Tyzzer's disease, however, was clearly the most significant infectious disease of gerbils in the UCLA School of Public Health colony. PMID:1207042

  3. Glucose supplement reverses the fasting-induced suppression of cellular immunity in Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Xu, De-Li; Wang, De-Hua

    2011-10-01

    Glucose plays an important role in immunity. Three day fasting will decrease cellular immunity and blood glucose levels in Mongolian gerbils (Meriones unguiculatus). In the present study, we tested the hypothesis that glucose supplement can reverse the fasting-induced suppression in cellular immunity in gerbils. Twenty-eight male gerbils were selected and randomly divided into fed and fasting groups. Half of the gerbils in each group were then provided with either 10% glucose water or pure water. After 66 h, each gerbil was injected with phytohaemagglutinin (PHA) solution to challenge cellular immunity. Results showed that glucose supplement restored blood glucose levels in fasted gerbils to those of the fed controls. It also recovered cellular immunity, body fat mass and serum leptin levels in fasted gerbils to the values of the fed controls. Blood glucose levels were positively correlated with body fat mass, leptin levels and cellular immune responses. Thymus and spleen masses, and white blood cells in fasted gerbils were not affected by glucose supplement. In general, our data demonstrate that glucose supplement could reverse fasting-induced suppression of cellular immunity in Mongolian gerbils. PMID:21885265

  4. Water deprivation up-regulates urine osmolality and renal aquaporin 2 in Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Xu, Meng-Meng; Wang, De-Hua

    2016-04-01

    To better understand how desert rodents adapt to water scarcity, we examined urine osmolality, renal distribution and expression of aquaporins (AQPs) in Mongolian gerbils (Meriones unguiculatus) during 7 days of water deprivation (WD). Urine osmolality of the gerbils during WD averaged 7503 mOsm kg(-1). Renal distributions of AQP1, AQP2, and AQP3 were similar to that described in other rodents. After the 7 day WD, renal AQP2 was up-regulated, while resting metabolic rate and total evaporative water loss decreased by 43% and 36%, respectively. Our data demonstrated that Mongolian gerbils showed high urine concentration, renal AQPs expression and body water conservation to cope with limited water availability, which may be critical for their survival during dry seasons in cold deserts. PMID:26806059

  5. Behaviour in a Colony of Meriones unguiculatus, the Mongolian Gerbil

    ERIC Educational Resources Information Center

    Williams, R. J.; Ladd, G. F.

    1973-01-01

    Describes animal behavior experiments that can be easily performed by secondary school students. The experiments illustrate territorial behavior, social order, and exploratory behavior in Mongolian gerbils. (JR)

  6. Partial sequence of Mongolian gerbil (Meriones unguiculatus) immunoglobulin gamma heavy chain constant region.

    PubMed

    Ukaji, Takao; Sumiyama, Daisuke; Kai, Osamu

    2011-10-01

    We determined the sequence of the immunoglobulin gamma heavy-chain constant (IGHC) region of the Mongolian gerbil (Meriones unguiculatus). To isolate a part of the IGHC complementary DNA, we designed primers on the basis of highly conserved sequences in mouse, rat and hamster. The deduced IGHC is structurally similar to counterparts in other mammalian species and shows 84.6% identity to the IGHC of hamster IgG, 76.6% to rat IgG1, 83.3% to rat IgG2a, 78.1% to mouse IgG1, 81.8% to mouse IgG2a, 79.1% to mouse IgG2b and 79.2% to mouse IgG3 at the nucleotide level. The results suggest that gerbil IgG is closely related to hamster IgG and rat IgG2a. PMID:21951909

  7. Migration behaviour and pathogenesis of five ascarid nematode species in the Mongolian gerbil Meriones unguiculatus.

    PubMed

    Cho, S; Egami, M; Ohnuki, H; Saito, Y; Chinone, S; Shichinohe, K; Suganuma, M; Akao, N

    2007-03-01

    To understand the characteristic features of the Mongolian gerbil, Meriones unguiculatus, as an animal model of ascarid infections, the migration behaviour and pathogenesis of larvae were investigated in experimentally infected gerbils. Embryonated eggs from each of Toxocara canis, Baylisascaris procyonis, B. transfuga, Ascaris suum, and A. lumbricoides were orally inoculated into gerbils and larvae were recovered from various organs at designated periods. In T. canis-infected gerbils, larvae were present in the liver 3 days after infection and in the skeletal muscle and brain via the heart and lungs at a similar rate. In B. procyonis- and B. transfuga-infected gerbils, larvae were present in the lungs within 24 h after infection, with some having reached the brain by that time. After 24 h, larvae of B. procyonis tended to accumulate in the brain, while those of B. transfuga accumulated in skeletal muscles. In A. suum- and A. lumbricoides-infected gerbils, larvae remained in the liver on day 5 post-infection and elicited pulmonary haemorrhagic lesions, which disappeared 7 days after initial infection. Thereafter, no larvae of any type were recovered. Ocular manifestations were frequently observed in T. canis- and B. procyonis infected gerbils, but were rare in B. transfuga-infected gerbils. In the cases of A. suum and A. lumbricoides, migration to the central nervous system and eyes was extremely rare, and larvae had disappeared by 2 weeks post-infection. Fatal neurological disturbances were observed in B. procyonis-infected gerbils, whereas irreversible non-fatal neurological symptoms were observed in the case of B. transfuga. PMID:17381866

  8. The pathology of the Mongolian Gerbil (Meriones unguiculatus): a review.

    PubMed

    Vincent, A L; Rodrick, G E; Sodeman, W A

    1979-10-01

    Both naturally occurring disease processes and experimental models of human disease in the Mongolian gerbil were reviewed. The gerbil was highly susceptible to cerebral infarction following unilateral ligation of one common carotid artery and was useful in studies of the pathogenesis of stroke. Spontaneous epileptiform seizures mimicked those of human idiopathic epilepsy, and both seizure-sensitive and resistant strains have been bred. Perhaps because of its more efficient nephron, the gerbil accumulated four to six times as much renal lead as the rat, and the gerbil has been proposed as an experimental model of lead nephropathy. On standard diets, about 10% of the animals became obese, and some showed decreased glucose tolerance, elevated serum immunoreactive insulin and diabetic changes in the pancreas and other organs. Some breeders exhibited hyperactivity of the adrenal cortex associated with hyperglycemia, hyperlipidemia and degenerative vascular disease. Although dietary supplements of cholesterol were toxic and did not induce atherosclerosis, the gerbil was useful in other studies of cholesterol absorption and metabolism. Spontaneous, insidious periodontal disease became evident after about 6 months on standard diets, and dental caries were induced by cariogenic diets or by pathodontic streptococci. Spontaneous neoplasia occurred in 8.4--24% of gerbils, usually after 2 years of life. Adrenal cortical, ovarian and cutaneous tumors were the most consistently reported neoplasms. PMID:92595

  9. Sexual maturation of the Mongolian gerbil (Meriones unguiculatus): a histological, hormonal and spermatic evaluation.

    PubMed

    Pinto-Fochi, Maria Etelvina; Negrin, Ana Carolina; Scarano, Wellerson Rodrigo; Taboga, Sebastião Roberto; Góes, Rejane Maira

    2016-04-01

    This study determined the phases of sexual development of the male Mongolian gerbil (Meriones unguiculatus) based on an integrative analysis of testicular morphology, hormonal data and sperm parameters. Male gerbils were analysed at 1, 7, 14, 21, 28, 35, 42, 50, 60, 70, 90, 100 and 120 days of age. Body, testicular and epididymal weights increased up to Day 70, 60 and 90, respectively. The impuberal phase, characterised by the presence of gonocytes, extended until Day 14. The prepubertal period lasted until Day 42, when puberty was achieved and a drastic increase in serum testosterone levels, mature adult Leydig cells and elongated spermatids was observed. Gerbils at 60 days of age showed a remarkable number of spermatozoa in the testis, epididymidis caput/corpus and cauda, and at Day 70 the maximum daily sperm production was reached. However, the gerbil may be considered sexually mature only from Day 90 onward, when sperm reserves become stable. The total transit time of spermatozoa along the epididymis of sexually mature gerbils was 11 days, with 1 day in the caput/corpus and 10 days in the cauda. These data cover a lacuna regarding the reproductive parameters of this rodent and provide foundations for its use in testicular toxicology studies. PMID:25455583

  10. Temperature acclimation in the Mongolian gerbil (Meriones unguiculatus): biochemical and organ weight changes.

    PubMed

    Steffen, J M; Roberts, J C

    1977-01-01

    1. Adult Mongolian gerbils (Meriones unguiculatus) were acclimated to 5 +/- 1, 24 +/- 1 and 34 +/- 1 degrees C for 6-8 weeks. 2. Body weights of temperature acclimated gerbils did not differ significantly from controls. Organ wt/body wt ratios of liver, kidney and heart increased in cold-acclimated and decreased in heat-acclimated gerbils. Adrenal wt/body wt ratio increased in the cold and was unchanged in the heat. Relative weights of brain, spleen, lungs, brown fat and ovaries + uterus did not change with temperature acclimation. 3. Cold acclimation produced significant increases in specific and total activity of brown fat alpha GPO and liver SO and AAO and in total activity of kidney SO; a significant decrease in liver mitochondrial ADP/O ratio with succinate as substrate; and no change in brown fat SO or liver alpha KGO. 4. Heat acclimation produced significant decreases in specific and total activity of liver and kidney SO, and in total activity of brown fat SO and alpha GPO, and liver AAO and alpha KGO. 5. The combined biochemical and organ wt changes seen in temperature-acclimated gerbils suggest that this species is capable of altering its metabolic thermogenic potential in response to a wide range of ambient temperatures. PMID:318267

  11. Environmental metabolomics reveal geographic variation in aerobic metabolism and metabolic substrates in Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Shi, Yao-Long; Chi, Qing-Sheng; Liu, Wei; Fu, He-Ping; Wang, De-Hua

    2015-06-01

    Mongolian gerbils (Meriones unguiculatus) have a large-scale distribution in northern China. Geographic physiological variations which related to energy and water metabolism are critical to animals' local adaptation and distribution. However, the underlying biochemical mechanism of such variation and its role in adaptation remains largely unknown. We used GC-MS metabolomics approach to investigate the biochemical adaptation of Mongolian gerbils from xeric (desert), transition (desert steppe) and mesic (typical steppe) environments. Gerbils in desert population had lower resting metabolic rate (RMR) and total evaporative water loss (TEWL) than mesic population. Serum metabolomics revealed that concentrations of five tricarboxylic acid cycle intermediates (citrate, cis-aconitate, α-ketoglutarate, fumarate and malate) were lower in desert population than mesic population. Gastrocnemius metabolomics and citrate synthase activity analysis showed a lower concentration of citrate and lower citrate synthase activity in desert population. These findings suggest that desert dwelling gerbils decrease RMR and TEWL via down-regulation of aerobic respiration. Gastrocnemius metabolomics also revealed that there were higher concentrations of glucose and glycolytic intermediates, but lower concentrations of lipids, amino acids and urea in desert population than mesic population. This geographic variation in metabolic substrates may enhance metabolic water production per oxygen molecule for desert population while constraining aerobic respiration to reduce RMR and TEWL. PMID:25817427

  12. Sequence determination of the heavy-chain constant region in four immunoglobulin classes of Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Ukaji, Takao; Sumiyama, Daisuke; Kai, Osamu

    2012-01-01

    We determined partial cDNA sequences of four immunoglobulin (Ig) classes-IgM, IgG1, IgE, and IgA-of Mongolian gerbil (Meriones unguiculatus). Each deduced Ig heavy-chain constant (IGHC) region-Cµ, Cγ1, Cε, and Cα-is structurally similar to its counterparts in the mouse and rat, and phylogenetic analysis suggests that the gerbil Igs are evolutionarily close to their counterparts. In spite of the high sequence homology to the other rodent Cγ sequences, the gerbil Cγ1 sequence differs from our previously reported Cγ2. This result indicates that the gerbil has at least two IgG subclasses. These four gerbil IGHC cDNA sequences will be useful for determining gerbil Ig isotypes and examining the expression of gerbil Ig mRNAs in response to parasitic and bacterial infections. PMID:22531724

  13. Effects of long-term exposure to trichloroethylene on the behavior of Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Kjellstrand, P; Bjerkemo, M; Mortensen, I; Månsson, L; Lanke, J; Holmquist, B

    1981-01-01

    Two groups of Mongolian gerbils (Meriones unguiculatus) were continuously exposed to 150 ppm trichloroethylene (TCE) for 71 and 106 d, respectively. The behavior of the animals was tested in a symmetrical maze baited with sunflower seeds during a period of 23 d, beginning at the end of exposure. One additional group was exposed for 150 d and then allowed 40 d free from exposure before the start of the maze test. Comparisons between the TCE- and air-exposed animals showed differences in the number of correct choices and the number of seeds consumed in the maze, both after 71 and 106 d of exposure and at the end of the 40-d rehabilitation period that followed the 150-d exposure. The results were interpreted in terms of the "emotionality" of the animals. PMID:7338941

  14. The complete mitochondrial genome of the Mongolian gerbil, Meriones unguiculatus (Rodentia: Muridae: Gerbillinae).

    PubMed

    Kim, Eun Bae; Lee, Sang-Goo

    2016-01-01

    The complete mitochondrial genome of the Mongolian gerbil, Meriones unguiculatus, was sequenced. The 16,360 bp long genome has 37 genes typical for rodent mitogenomes, including 22 tRNA genes, 2 rRNA genes, and 13 protein-coding genes. The total GC content of the mitochondrial genome is 36.96% with the base composition of 32.61% A, 23.71% C, 13.24% G, and 30.44% T. Translational terminators of three genes (cytb, cox3, and nad4) were generated by the addition of 3' A residues to the mRNA. This novel rodent mitochondrial genome will provide comparable information for understanding the rodent mitochondrial evolution. PMID:25185794

  15. The Effect of Different Working Definitions on Behavioral Research Involving Stereotypies in Mongolian Gerbils (Meriones unguiculatus)

    PubMed Central

    Moons, Christel PH; Breugelmans, Sofie; Cassiman, Nele; Kalmar, Isabelle D; Peremans, Kathelijne; Hermans, Katleen; Ödberg, Frank O

    2012-01-01

    Many sources of variation in animal experiments are related to characteristics of the animal or its husbandry conditions. In ethologic studies, observational methods can also affect interexperimental variation. Different descriptions for a behavior can lead to divergent findings that may be incorrectly attributed to other factors if not recognized as stemming from a classification dissonance. Here we discuss 2 observational studies in Mongolian gerbils (Meriones unguiculatus). The first study describes how data vary when 2 different working definitions are used for stereotypic digging: WDmor, a definition based on a morphologic description of the behavior, and WD12, a definition that relies mainly on a duration criterion of digging bouts (greater than 12 s). The total duration and number of stereotypic bouts were 22.0% and 63.1% lower, respectively, when WD12 was applied compared with WDmor. However, strong correlations existed between data generated by WDmor and WD12, indicating that the 2 definitions yielded qualitatively similar results. The second study provides the first report that laboratory gerbils develop stereotypic behavior that is characterized by alternating bouts of digging and bar-gnawing. Of the 1685 stereotypy bouts investigated, 9.1% comprised both stereotypies, 87.6% consisted of digging only, and 3.3% consisted of bar gnawing only. Working definitions that neglect combined stereotypies can result in considerable underestimation of stereotypic behavior in Mongolian gerbils. PMID:22776116

  16. Implication of metabolomic profiles to wide thermoneutral zone in Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Shi, Yaolong; Wang, Dehua

    2016-07-01

    Mongolian gerbils (Meriones unguiculatus) have evolved a wide thermoneutral zone (26.5-38.9 °C) and high upper critical temperature, and appear to have a high tolerance for heat exposure. Here, we use a metabolomic approach to measure global metabolite profiles for gerbils between lower (27 °C) and upper critical temperatures (38 °C) to investigate the role of metabolomic characterization in maintaining basal metabolic rates within a wide thermoneutral zone. We found that in serum and liver, 14 and 19 metabolites were significantly altered, respectively. In the aerobic respiration-related tricarboxylic cycle (TCA), 5 intermediates (isocitric acid, cis-aconitic acid, α-ketoglutaric acid, fumaric acid and malic acid) were increased in serum in 38 °C animals; however, no such increase was found in the liver. A stable level of hepatic TCA cycle intermediates may be related to the steady state of aerobic respiration at 38 °C. Metabolomic results also revealed that acute heat exposure caused increased oxidative stress and low molecular weight antioxidants in Mongolian gerbils. Increased methionine and 2-hydroxybutyrate suggest an accelerated synthesis of glutathione. Increased urate and its precursors, inosine and hypoxanthine, were detected at 38 °C. Glucuronate, threonate and oxalate involved in ascorbate synthesis and degradation were increased in serum at 38 °C. In conclusion, although dramatic metabolomic variation was found, a stable hepatic TCA cycle may contribute to maintaining a constant basal metabolic rate within a wide thermoneutral zone in Mongolian gerbils. PMID:26749160

  17. Brain atlas of the Mongolian gerbil (Meriones unguiculatus) in CT/MRI-aided stereotaxic coordinates.

    PubMed

    Radtke-Schuller, Susanne; Schuller, Gerd; Angenstein, Frank; Grosser, Oliver S; Goldschmidt, Jürgen; Budinger, Eike

    2016-09-01

    A new stereotaxic brain atlas of the Mongolian gerbil (Meriones unguiculatus), an important animal model in neurosciences, is presented. It combines high-quality histological material for identification of brain structures with reliable stereotaxic coordinates. The atlas consists of high-resolution images of frontal sections alternately stained for cell bodies (Nissl) and myelinated fibers (Gallyas) of 62 rostro-caudal levels at intervals of 350 μm. Brain structures were named according to the Paxinos nomenclature for rodents. The accuracy of the stereotaxic coordinate system was improved substantially by comparing and matching the series of histological sections to in vivo brain images of the gerbil obtained by magnetic resonance imaging (MRI). The skull outlines corresponding to the MR images were acquired using X-ray computerized tomography (CT) and were used to establish the relationship between coordinates of brain structures and skull. Landmarks such as lambda, bregma, ear canals and occipital crest can be used to line up skull and brain in standard atlas coordinates. An easily reproducible protocol allows sectioning of experimental brains in the standard frontal plane of the atlas. PMID:27507296

  18. Blood supply to the retina and the lens in the gerbil (Meriones unguiculatus).

    PubMed

    Imada, Hideki; Isomura, Genzoh; Miyachi, Ei-ichi

    2003-03-01

    The blood supply to the retina and the lens in 32 gerbils (Meriones unguiculatus) of both sexes from infancy to maturity was studied under light and stereoscopic microscopes, and a scanning electron microscope. Mercox (CL-2R; Dai Nippon Ink, Tokyo, Japan) was injected into the left ventricle of 30 animals in order to visualize the blood supply to the retina and the lens from the ophthalmic artery. The central retinal artery arises from the ophthalmic artery, passes through the papilla of the optic nerve together with the central retinal vein and penetrates the vitreous space (cavity of the eye) between the lens and the internal limiting membrane of the retina, where it divides into the central branches covering the lens and the parietal branches to supply the retina. The former passes through the hyaloid space after branching several arterioles and then covers the lens like a network from its medial and marginal sides. Different from small experimental animals, the parietal branches, just after separating from the central one, divides into the nasal, dorsal and temporal branches in the vitreous space, each of which then subdivides to distribute across the retina on the inner limiting membrane, then delineates the membrana vasculosa retinae. This basal pattern of vasculization 1 day after birth continues to death. Both the central and parietal branches of the central retinal artery correspond to the branches of the hyaloid artery in embryo and the latter is preserved in adult gerbils. PMID:12680468

  19. [Histological study of the visceral organs of Mongolian gerbil Meriones unguiculatus as a subject in spaceflight experiments].

    PubMed

    Kaplanskiĭ, A S; Durnova, G N; Orlov, O I; Il'in, E I

    2008-01-01

    Survey histological study of the heart, lung, liver, kidney, pancreas, adrenals, thymus, spleen, testicles of the Mongolian gerbil Meriones unguiculatus with a body mass of about 27 g showed their macro- and microscopic similarity with the organs of laboratory rats and mice notwithstanding some slight differences. For instance, the ascending knee of Hengle's loop in the gerbil kidney is much better developed and forms in whole a kind of a singular cortical fiber bordering the medulla. It is the well-developed parts of Hengle's ascending loop in gerbil that ensures a more complete water reabsorption decrease the quantity of urine and sharply reduce the amount of exogenous fluid vitally important for animals in arid areas. The Mongolian gerbil is distinguished by large adrenals and small corticosteroid-sensitive thymus and spleen suggesting high sensitivity of this animal to stresses. Spleen abundance of both mature and immature megacariosities--thrombogoniums--explains the rapid coagulability as compared with rats and mice. PMID:18564566

  20. Chromatin organization and remodeling of interstitial telomeric sites during meiosis in the Mongolian gerbil (Meriones unguiculatus).

    PubMed

    de la Fuente, Roberto; Manterola, Marcia; Viera, Alberto; Parra, María Teresa; Alsheimer, Manfred; Rufas, Julio S; Page, Jesús

    2014-08-01

    Telomeric DNA repeats are key features of chromosomes that allow the maintenance of integrity and stability in the telomeres. However, interstitial telomere sites (ITSs) can also be found along the chromosomes, especially near the centromere, where they may appear following chromosomal rearrangements like Robertsonian translocations. There is no defined role for ITSs, but they are linked to DNA damage-prone sites. We were interested in studying the structural organization of ITSs during meiosis, a kind of cell division in which programmed DNA damage events and noticeable chromatin reorganizations occur. Here we describe the presence of highly amplified ITSs in the pericentromeric region of Mongolian gerbil (Meriones unguiculatus) chromosomes. During meiosis, ITSs show a different chromatin conformation than DNA repeats at telomeres, appearing more extended and accumulating heterochromatin markers. Interestingly, ITSs also recruit the telomeric proteins RAP1 and TRF1, but in a stage-dependent manner, appearing mainly at late prophase I stages. We did not find a specific accumulation of DNA repair factors to the ITSs, such as γH2AX or RAD51 at these stages, but we could detect the presence of MLH1, a marker for reciprocal recombination. However, contrary to previous reports, we did not find a specific accumulation of crossovers at ITSs. Intriguingly, some centromeric regions of metacentric chromosomes may bind the nuclear envelope through the association to SUN1 protein, a feature usually performed by telomeres. Therefore, ITSs present a particular and dynamic chromatin configuration in meiosis, which could be involved in maintaining their genetic stability, but they additionally retain some features of distal telomeres, provided by their capability to associate to telomere-binding proteins. PMID:24907260

  1. Coconut oil enhances tomato carotenoid tissue accumulation compared to safflower oil in the Mongolian gerbil ( Meriones unguiculatus ).

    PubMed

    Conlon, Lauren E; King, Ryan D; Moran, Nancy E; Erdman, John W

    2012-08-29

    Evidence suggests that monounsaturated and polyunsaturated fats facilitate greater absorption of carotenoids than saturated fats. However, the comparison of consuming a polyunsaturated fat source versus a saturated fat source on tomato carotenoid bioaccumulation has not been examined. The goal of this study was to determine the influence of coconut oil and safflower oil on tomato carotenoid tissue accumulation in Mongolian gerbils ( Meriones unguiculatus ) fed a 20% fat diet. Coconut oil feeding increased carotenoid concentrations among many compartments including total carotenoids in the serum (p = 0.0003), adrenal glandular phytoene (p = 0.04), hepatic phytofluene (p = 0.0001), testicular all-trans-lycopene (p = 0.01), and cis-lycopene (p = 0.006) in the prostate-seminal vesicle complex compared to safflower oil. Safflower oil-fed gerbils had greater splenic lycopene concentrations (p = 0.006) compared to coconut oil-fed gerbils. Coconut oil feeding increased serum cholesterol (p = 0.0001) and decreased hepatic cholesterol (p = 0.0003) compared to safflower oil. In summary, coconut oil enhanced tissue uptake of tomato carotenoids to a greater degree than safflower oil. These results may have been due to the large proportion of medium-chain fatty acids in coconut oil, which might have caused a shift in cholesterol flux to favor extrahepatic carotenoid tissue deposition. PMID:22866697

  2. Development of the nasolacrimal apparatus in the Mongolian gerbil (Meriones unguiculatus), with notes on network topology and function.

    PubMed

    Rehorek, Susan J; Cunningham, Jayna; Bruening, Amanda E; Johnson, Jessica L; Bhatnagar, Kunwar P; Smith, Timothy D; Hillenius, Willem J

    2015-09-01

    The nasolacrimal apparatus (NLA) is a multicomponent functional system comprised of multiple orbital glands (up to four larger multicellular exocrine structures), a nasal chemosensory structure (vomeronasal organ: VNO), and a connecting duct (nasolacrimal duct: NLD). Although this system has been described in all tetrapod vertebrate lineages, albeit not always with all three main components present, considerably less is known about its ontogeny. The Mongolian gerbil (Meriones unguiculatus) is a common lab rodent in which the individual components of the adult NLA have been well studied, but as yet nothing is known about the ontogeny of the NLA. In this study, serial sections of 15 fetal and three adult Mongolian gerbil heads show that the development of the NLA falls into three fetal stages: inception (origin of all features), elongation (lengthening of all features), and expansion (widening of all features). No postnatal or juvenile specimens were observed in this study, but considerable growth evidently occurs before the final adult condition is reached. The development of the orbital glands and the VNO in the Mongolian gerbil is largely consistent with those in other mammals, despite a slight nomenclatural conundrum for the anterior orbital glands. However, the Mongolian gerbil NLD follows a more circuitous route than in other tetrapods, due mainly to the convoluted arrangement of the narial cartilages, the development of a pair of enlarged incisors as well as an enlarged infraorbital foramen. The impact of these associated features on the ontogeny and phylogeny of the NLA could be examined through the approach of network science. This approach allows for the incorporation of adaptations to specific lifestyles as potential explanations for the variation observed in the NLA across different tetrapod clades. PMID:25845915

  3. Limits to sustained energy intake. XIX. A test of the heat dissipation limitation hypothesis in Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Yang, Deng-Bao; Li, Li; Wang, Lu-Ping; Chi, Qing-Sheng; Hambly, Catherine; Wang, De-Hua; Speakman, John R

    2013-09-01

    We evaluated factors limiting lactating Mongolian gerbils (Meriones unguiculatus) at three temperatures (10, 21 and 30°C). Energy intake and daily energy expenditure (DEE) increased with decreased ambient temperature. At peak lactation (day 14 of lactation), energy intake increased from 148.7±5.7 kJ day(-1) at 30°C to 213.1±8.2 kJ day(-1) at 21°C and 248.7±12.3 kJ day(-1) at 10°C. DEE increased from 105.1±4.0 kJ day(-1) at 30°C to 134.7±5.6 kJ day(-1) at 21°C and 179.5±8.4 kJ day(-1) at 10°C on days 14-16 of lactation. With nearly identical mean litter sizes, lactating gerbils at 30°C exported 32.0 kJ day(-1) less energy as milk at peak lactation than those allocated to 10 or 21°C, with no difference between the latter groups. On day 14 of lactation, the litter masses at 10 and 30°C were 12.2 and 9.3 g lower than those at 21°C, respectively. Lactating gerbils had higher thermal conductance of the fur and lower UCP-1 levels in brown adipose tissue than non-reproductive gerbils, independent of ambient temperature, suggesting that they were attempting to avoid heat stress. Thermal conductance of the fur was positively related to circulating prolactin levels. We implanted non-reproductive gerbils with mini-osmotic pumps that delivered either prolactin or saline. Prolactin did not influence thermal conductance of the fur, but did reduce physical activity and UCP-1 levels in brown adipose tissue. Transferring lactating gerbils from warm to hot conditions resulted in reduced milk production, consistent with the heat dissipation limit theory, but transferring them from warm to cold conditions did not elevate milk production, consistent with the peripheral limitation hypothesis, and placed constraints on pup growth. PMID:23737554

  4. Scent-marking and sexual activity may reflect social hierarchy among group-living male Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Shimozuru, Michito; Kikusui, Takefumi; Takeuchi, Yukari; Mori, Yuji

    2006-12-30

    Social hierarchy plays an important role in the lives of gregarious species. We investigated how social hierarchy between male Mongolian gerbils (Meriones unguiculatus) housed together before sexual maturity affected their scent-marking behavior, endocrine status and physical traits as adults. The social rank between paired males was assessed based on sexual activity in adulthood at 18 and 20 weeks of age. In most cases, the male that showed higher sexual activity at 18 weeks also exhibited greater sexual performance at 20 weeks, suggesting a precedence relationship between paired males regarding reproductive opportunity. Sexually active males scent-marked more often than their cage mate, particularly after a sexual experience. No significant differences in physical traits (e.g., the weight of the ventral gland, testes and adrenal glands) or endocrine status (e.g., fecal testosterone and corticosterone levels) were found between the two males. These findings suggest that social rank between familiar males formed during cohabitation, and rank was closely correlated with scent-marking activity, but not with endocrine status. PMID:16959280

  5. Disaccharidase deficiencies in Mongolian gerbils (Meriones unguiculatus) protected against Giardia lamblia.

    PubMed

    Mohammed, S R; Faubert, G M

    1995-01-01

    The activities of the disaccharidases lactase, maltase, sucrase and trehalase were examined in gerbils during Giardia lamblia infections. In a primary infection with trophozoites, the activities of all four enzymes were reduced from day 10 post-infection (p.i.) and remained at low levels well past the elimination phase of the infection. However, during a challenge infection, the disaccharidase decreases were short-lived, with impairments being seen only on days 2 and/or 4 post-challenge (p.c.). Sucrase activity was not affected by a challenge infection. When 0.1 mg of a soluble extract of G. lamblia trophozoites was used to challenge gerbils previously exposed to the live parasite, the pattern and duration of enzyme deficiencies were comparable with those observed after the challenge with the live parasite. In addition, decreasing the extract dose used to challenge the gerbils led to smaller disaccharidase deficiencies. G. lamblia-infected gerbils were also challenged with a soluble extract of Entamoeba histolytica trophozoites, and this had no effect on the disaccharidase activities. Therefore, the presence of the intact parasite was not necessary to induce enzyme reductions in immune animals. In addition, the effects seen during the secondary infection were parasite-specific and may have involved the host's immune response to Giardia antigens. Immune gerbils were further challenged with the in vitro-released excretory/secretory products of G. lamblia. Under our experimental conditions, disaccharidase activities were found to be affected by these products in a manner that was inconsistent with the results of the live parasite challenge, and this merits further study. PMID:7479650

  6. Effects of age at first-pairing on the reproductive performance of Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Kai, O; Sakemi, K; Suzuki, Y; Sonoda, Y; Imai, K

    1995-10-01

    Effects of age at first-pairing on the reproductive performance of the gerbil were studied throughout the reproductive life. Six groups of 7-30 female gerbils were paired monogamously with males at different ages. Out of 101 pairs in 6 groups, 79 (78.2%) produced 1 or more litters. The mean litter size at birth and mean weaning rate of 846 litters were 4.4 (totally 3,733 pups) and 67.4% (2,517 pups), respectively. Reproduction was compared in the 6 age groups. The littering rate (No. of females with litters/No. of female paired) was significantly lower in two groups in which mature females were paired with age-matched males (Group 4) or the oldest females with younger, sexually mature males (Group 6). The interval from pairing to the first litter was shortest in two groups in which mature females were paired with one month older, sexually mature males (Groups 3 and 5). Although the oldest pairs (Group 6) produced about 7 litters, the pairs from the other 5 groups produced about 10 or more litters throughout their reproductive life. The weaning rate was significantly higher in Group 6 (the oldest pairs) than in the younger groups. The effects of parity on reproduction were estimated from the data for the 61 pairs which produced more than 8 litters in the 6 groups. The number of pups at birth and the weaning rate were decreased in last 20-30% of the total parity in all 6 groups, although the age at the last litter in all groups was significantly different. The data suggest that any decline in reproduction may be due to not age but parity in the Mongolian gerbil. PMID:8575545

  7. Module Equipped with a Life-Support System for Space Experiments with Mongolian Gerbils (Meriones Unguiculatus)

    NASA Astrophysics Data System (ADS)

    Ilyin, E. A.; Smirnov, I. A.; Soldatov, P. E.; Guryeva, T. S.; Mednikova, E. I.

    2008-06-01

    A successful experiment with 12 Mongolian gerbils was performed during the 12-day flight of Russian automatic spacecraft Foton-M3 (September 14-26, 2007). Foton-M3 was not equipped with an air supply system. Due to this, a self-contained "CONTOUR" module equipped with its own Life-Support System, was developed. The cage for animals was equipped with yellow LEDs. The day/night cycle was 12:12 hours. In addition, the module was equipped with a digital video recorder located on the outside surface in front of a transparent window. In space flight, the animals were provided with food bars made of natural products and contained about 20% of water. This moisture met gerbils requirements in water; therefore, the module was not equipped with a water supply system. In the module, the environmental parameters were as follows: p02 = 143-156 (mean 150) mm Hg, pC02 - not more than 0.76 (mean 0.64) mm Hg, temperature = 23-28 (mean 26.7) °C, and RH = 29% at the beginning and 57% at the end of flight (mean 39%). Throughout the entire flight video recording of the animals was performed continuously during the daytime.

  8. Dendritic Morphology of Caudal Periaqueductal Gray Projecting Retinal Ganglion Cells in Mongolian Gerbil (Meriones unguiculatus)

    PubMed Central

    Ren, Chaoran; Pu, Mingliang; Cui, Qi; So, Kwok-Fai

    2014-01-01

    In this study we investigated the morphological features of the caudal periaqueductal gray (cPAG)-projecting retinal ganglion cells (RGCs) in Mongolian gerbils using retrograde labeling, in vitro intracellular injection, confocal microscopy and three-dimensional reconstruction approaches. cPAG-projecting RGCs exhibit small somata (10–17 µm) and irregular dendritic fields (201–298 µm). Sizes of somata and dendritic fields do not show obvious variation at different distance from the optic disk (eccentricity). Dendrites are moderately branched. Morphological analysis (n = 23) reveals that cPAG-projecting RGCs ramified in sublamina a and b in the inner plexiform layer. These cells exhibit different stratification patterns based on the thickness of dendritic bands in sublaminas a and b: majority of analyzed cells (16 out of 23) have two bands of arborizations share similar thickness. The rest of analyzed cells (7 out of 23) exhibit thinner band in sublamina a than in sublamina b. Together, the present study suggests that cPAG of Mongolian gerbil could receive direct retinal inputs from two types of bistratified RGCs. Furthermore, a small subset of melanopsin-expressing RGCs (total 41 in 6 animals) is shown to innervate the rostral PAG (rPAG). Functional characteristics of these non-visual center projecting RGCs remain to be determined. PMID:25054882

  9. Restricted loss of olivocochlear but not vestibular efferent neurons in the senescent gerbil (Meriones unguiculatus)

    PubMed Central

    Radtke-Schuller, Susanne; Seeler, Sabine; Grothe, Benedikt

    2015-01-01

    Degeneration of hearing and vertigo are symptoms of age-related auditory and vestibular disorders reflecting multifactorial changes in the peripheral and central nervous system whose interplay remains largely unknown. Originating bilaterally in the brain stem, vestibular and auditory efferent cholinergic projections exert feedback control on the peripheral sensory organs, and modulate sensory processing. We studied age-related changes in the auditory and vestibular efferent systems by evaluating number of cholinergic efferent neurons in young adult and aged gerbils, and in cholinergic trigeminal neurons serving as a control for efferents not related to the inner ear. We observed a significant loss of olivocochlear (OC) neurons in aged compared to young adult animals, whereas the overall number of lateral superior olive (LSO) cells was not reduced in aging. Although the loss of lateral and medial olivocochlear (MOC) neurons was uniform and equal on both sides of the brain, there were frequency-related differences within the lateral olivocochlear (LOC) neurons, where the decline was larger in the medial limb of the superior olivary nucleus (high frequency representation) than in the lateral limb (middle-to-low frequency representation). In contrast, neither the number of vestibular efferent neurons, nor the population of motor trigeminal neurons were significantly reduced in the aged animals. These observations suggest differential effects of aging on the respective cholinergic efferent brainstem systems. PMID:25762929

  10. Impact of psychosocial stress on pineal structure of male gerbils (Meriones unguiculatus, cricetidae).

    PubMed

    Heinzeller, T

    1985-01-01

    Stress responses were investigated in 5-month-old male gerbils. Breeders having no pubescent litters served as controls. The first experimental group never left their parents' cage and were thereby fought by higher-ranking males; the second and third groups were stressed for a week by four daily 1-minute encounters with trained fighters, the second group during daytime, the third during the dark period. The first and second groups developed signs of gonadal regression, the third did not. The adrenals of the first group weighed the same as those of controls; the adrenals of both other groups were increased in weight. In the adrenal medulla of all experimental groups, a large number of cells were densely packed with noradrenaline-containing vesicles. In each experimental group the pineal changes included a remarkable decrease in nuclear size of pinealocytes, an increased number of colloidal cysts, and a reduction of that portion of the plasmalemma that is lined by subsurface cisterns. All these changes are interpreted in terms of pineal activation, as are the increased number of membrane whirls found in the first group. The third group exhibited an additional decrease in the size of mitochondria and in the number of "synaptic" structures. This finding and the day-night differences in the gonadal response indicate that stress interferes with the metabolic cyclicity of the pineal gland. However, it remains indiscernible whether the pineal stress reaction signals a general activation of the gland or a change in it's temporal activity patterns. PMID:3831304

  11. Acoustical cues for sound localization by the Mongolian gerbil, Meriones unguiculatus

    NASA Astrophysics Data System (ADS)

    Maki, Katuhiro; Furukawa, Shigeto

    2005-08-01

    The present study measured the head-related transfer functions (HRTFs) of the Mongolian gerbil for various sound-source directions, and explored acoustical cues for sound localization that could be available to the animals. The HRTF exhibited spectral notches for frequencies above 25 kHz. The notch frequency varied systematically with source direction, and thereby characterized the source directions well. The frequency dependence of the acoustical axis, the direction for which the HRTF amplitude was maximal, was relatively irregular and inconsistent between ears and animals. The frequency-by-frequency plot of the interaural level difference (ILD) exhibited positive and negative peaks, with maximum values of 30 dB at around 30 kHz. The ILD peak frequency had a relatively irregular spatial distribution, implying a poor sound localization cue. The binaural acoustical axis (the direction with the maximum ILD magnitude) showed relatively orderly clustering around certain frequencies, the pattern being fairly consistent among animals. The interaural time differences (ITDs) were also measured and fell in a +/-120 μs range. When two different animal postures were compared (i.e., the animal was standing on its hind legs and prone), small but consistent differences were found for the lower rear directions on the HRTF amplitudes, the ILDs, and the ITDs.

  12. Assessment of Blood Collection from the Lateral Saphenous Vein for Microfilaria Counts in Mongolian Gerbils (Meriones unguiculatus) Infected with Brugia pahangi

    PubMed Central

    Alworth, Leanne C; Berghaus, Roy D; Kelly, Lisa M; Supakorndej, Prasit; Burkman, Erica J; Savadelis, Molly D; Cooper, Tanya L; Salyards, Gregory W; Harvey, Stephen B; Moorhead, Andrew R

    2015-01-01

    The NIH guidelines for survival bleeding of mice and rats note that using the retroorbital plexus has a greater potential for complications than do other methods of blood collection and that this procedure should be performed on anesthetized animals. Lateral saphenous vein puncture has a low potential for complications and can be performed without anesthesia. Mongolian gerbils (Meriones unguiculatus) are the preferred rodent model for filarial parasite research. To monitor microfilaria counts in the blood, blood sampling from the orbital plexus has been the standard. Our goal was to refine the blood collection technique. To determine whether blood collection from the lateral saphenous vein was a feasible alternative to retroorbital sampling, we compared microfilaria counts in blood samples collected by both methods from 21 gerbils infected with the filarial parasitic worm Brugia pahangi. Lateral saphenous vein counts were equivalent to retroorbital counts at relatively high counts (greater than 50 microfilariae per 20 µL) but were significantly lower than retroorbital counts when microfilarial concentrations were lower. Our results indicate that although retroorbital collection may be preferable when low concentrations of microfilariae need to be enumerated, the lateral saphenous vein is a suitable alternative site for blood sampling to determine microfilaremia and is a feasible refinement that can benefit the wellbeing of gerbils. PMID:26678366

  13. Rapid and fine adjustment of corticosteroidogenesis operating in the adrenal gland of the Mongolian gerbil (Meriones unguiculatus) superfused in-vitro.

    PubMed

    Fenske, M

    1987-09-01

    Corticosteroid release from adrenals of male adult Mongolian gerbils (Meriones unguiculatus) has been studied during continuous and discontinuous in-vitro superfusion. Corticosteroid output from glands of untreated animals with plasma corticosteroid levels below 300 ng/ml was 3.3 +/- 0.3 ng/adrenal pair/min and decreased only slightly with the length of superfusion (60 min: 3.1 +2- 0.3 ng/adrenal pair/min). In-vitro secretion was significantly higher from adrenals of animals which had corticosteroid plasma levels of over 300 ng/ml, underwent clonic-tonic seizures, or were injected with 6 IU/animal (1-24) ACTH. On the other hand, injection of 2 X 50 micrograms dexamethasone markedly decreased corticosteroid plasma levels but had no significant effect on in-vitro secretion of corticosteroids. In contrast to the slow and small, but long-lasting stimulation of corticosteroid secretion elicited by (1-24) ACTH, secretion could be changed within much shorter time periods, either by the addition of plasma proteins to superfusion medium or by stops of superfusion flow. While a significant stimulation of corticosteroid output occurred after the addition of 1% or 10% BSA or rat plasma, stops of superfusion flow for 1.5 or 10 min resulted in a strong inhibition of steroidogenesis, as is evident from corticosteroid amounts found in the first 1-min samples after re-start of superfusion. Within 4-5 min after re-start of superfusion, secretion returned to basal values. Corticosteroid amounts secreted from adrenals superfused in-vitro were significantly higher than those secreted from adrenals incubated in-vitro. In addition, prolonged incubation suppressed corticosteroidogenesis (30 min: 100%, 60 min: 64%, 90 min: 56%, 120 min: 59%). The results demonstrate that superfusion of sliced adrenal tissue gives insights into aspects of adrenal function, including the rapid changes in synthesis and secretion after flow stops which cannot be investigated by incubation of either tissue

  14. Poorly differentiated cutaneous carcinoma of non-sebaceous origin in a 3-year-old Mongolian gerbil (Meriones unguiculatus).

    PubMed

    Fenton, Heather; Forzán, María J; Desmarchelier, Marion; Woodland, Meghan; Sayi, Soraya; Gilroy, Cornelia V

    2016-01-01

    A 3-year-old female gerbil developed a non-healing skin wound due to a malignant neoplasm. Histology, immunohistochemistry (cytokeratin 19 positive; vimentin, estrogen, and progesterone receptor negative), and electron microscopy (no desmosomes or melanosomes) revealed an undifferentiated carcinoma with pulmonary metastasis. Unlike in previous reports, it did not arise from the abdominal pad's sebaceous gland. PMID:26740704

  15. La Crosse viremias in Mongolian gerbils (Meriones unguiculatis).

    PubMed

    Osorio, J E; Yuill, T M

    1996-11-01

    We examined the usefulness of mongolian gerbils (Meriones unguiculatus) as a new animal model for La Crosse virus (LACV) studies. Gerbils were exposed to LACV by either intramuscular (im) inoculation or exposure to transovarially infected Aedes triseriatus. Our studies indicate that gerbils may be a suitable animal model for LACV infection. Gerbils were susceptible to LACV, survived viral infection, and developed viremias and neutralizing antibody titers following exposure by im injection and by the bite of infected mosquitoes. Moreover, they are attractive to mosquito vectors. Gerbils have other advantages as laboratory vertebrate hosts for LACV; they are inexpensive, breed in captivity, and are usually mild-mannered and easy to handle. Thus, gerbils are a suitable model in the study of LACV pathogenesis as well as of transplacental and vector transmission. PMID:8940992

  16. Effects of diet quality on phenotypic flexibility of organ size and digestive function in Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Liu, Quan-Sheng; Wang, De-Hua

    2007-07-01

    In the context of evolution and ecology, there is a trade-off between the benefits of processing food through a digestive system with specific phenotypic attributes and the cost of maintaining and carrying the digestive system. In this study, we tested the hypothesis that digestive modulations at several levels can match each other to meet the energy and nutrient demands of Mongolian gerbils, a small granivorous rodent species, by acclimating them to a high-quality diet diluted with alfalfa powder. Mongolian gerbils on the diluted diet maintained metabolizable energy intake by an integrated processing response (IPR), which included increases in dry matter intake, gut capacity and rate of digesta passage after 2-weeks of acclimation. Down-regulation of hydrolytic enzyme activity in the intestinal brush-border membrane supported the adaptive modulation hypothesis. The absence of up-modulation of summed enzyme hydrolytic capacity on the diluted diet indicated that greater mass of small intestine on a high-fibre diet is not a direct indicator of digestive or absorptive capacity. Changes in mass of vital organs and carcass suggested that the amount of energy allocated to various organs and hence physiological functions was regulated in response to diet shift. PMID:17333208

  17. Larval migration of the ascarid nematode Toxocara canis following infection and re-infection in the gerbil Meriones unguiculatus.

    PubMed

    Flecher, M C; Musso, C; Martins, I V F; Pereira, F E L

    2016-09-01

    A morphological and immunohistochemical study of larval migration patterns was performed in gerbils that were infected once (primary infected group) or twice (secondary infected group) with 1500 eggs of Toxocara canis. Animals from the primary infected and the re-infected group were killed at different times after infection, and larvae were counted in the intestines, liver, lungs and brain. Fragments of all organs were formalin fixed and paraffin embedded for histology and immunohistochemistry analyses (using polyclonal anti-Toxocara serum raised in rabbits infected with T. canis). In the primary infected group, larvae were more abundant in the intestine at 24 h, in the liver and lungs between 24 and 72 h and in the brain after 96 h; larvae predominated in the brain for up to 60 days after infection. In the re-infected group, an increase in the number of larvae in the liver and a reduction in the number of larvae in the brain was observed up to 60 days after re-infection. Inflammatory reactions were absent or limited. Eosinophils and loose granulomata were observed around the larvae and their antigens in the primary infected group and were more severe. Many eosinophils and typical epithelioid granulomata were observed around larvae in the re-infected group. These results demonstrate that the migration pattern of T. canis larvae in gerbils is similar to that in mice and rats, exhibiting a late neurotropic stage. In the re-infected group, there was histological evidence of an adaptive T-helper 2 (Th-2) response, and larvae were apparently retained within granulomata in the liver, without obvious signs of destruction. PMID:26337823

  18. Response map properties of units in the dorsal cochlear nucleus of barbiturate-anesthetized gerbil (Meriones unguiculatus).

    PubMed

    Gdowski, G T; Voigt, H F

    1997-03-01

    The response map scheme introduced by Evans and Nelson (1973) and modified by others, including Davis et al. (1996) for use with gerbils, has been used primarily for classifying units recorded in the cochlear nucleus of unanesthetized decerebrate preparations. Units lacking spontaneous activity (SpAc) have been classified as either type I/III or type II units based on the relative strength of their responses to broad-band noise compared to their responses to best-frequency (BF) tones. The relative noise index (rho), a ratio of these responses after SpAc is subtracted out, provides a convenient measure of this relative strength. In this paper, responses of 320 units recorded in the dorsal cochlear nucleus (DCN) of barbiturate-anesthetized gerbils to short-duration BF tones and broad-band noise were recorded. Since 87.5% of these units lacked SpAc, their response maps resembled those of type II and type I/III units. Units were characterized by rho and the normalized slope (m) of a best line fit to the BF rate versus level plot starting from the sound level corresponding to the first inflection point of the rate curve (typically its maximum value or the start of its sloping saturation). The distributions of rho and m values do not form distinct clusters as they do for units in the decerebrate preparation. Thus, the criteria developed for classifying DCN units in the decerebrate preparation do not appear appropriate for units in the barbiturate-anesthetized preparation. Deposits of horseradish peroxidase were used to locate 52 units. Most of the low SpAc units, 56% with poor noise responses (5/9) and nearly 70% with strong noise responses (25/36), and nearly all of the high SpAc units (6/7), were located either within or below the fusiform cell layer. PMID:9083807

  19. Effects of exposure to estradiol and estradiol plus testosterone on the Mongolian gerbil (Meriones unguiculatus) female prostate.

    PubMed

    Da Silva, Diego Augusto Lopes; Zanatelli, Marianna; Shinohara, Filipe Zardini; Góes, Rejane Maira; Dos Santos, Fernanda Cristina Alcântara; Vilamaior, Patricia Simone Leite; Taboga, Sebastião Roberto

    2013-05-01

    The female prostate is a differentiated organ found in several mammal species, including humans and rodents. This gland has been related to important functions on female reproductive biology. Although the factors, which regulate prostate's development and activity are not well known, its functionality has been related to steroid hormones. It is well established that cyclic changes of estradiol and progesterone levels promote histophysiological adaptations of the whole female body. In contrast, only a few is found about those adaptations in female prostate. Thus, this study aimed to evaluate the effect of estradiol and estradiol + testosterone association on gerbil female prostate in order to verify, which hormonal associations are necessary to its homeostasis. For this, adult females had the ovaries surgically removed. After recovering, they received estradiol and estradiol + testosterone doses through 30 days, each 48 h. The prostatic tissue underwent morphological and morphometric-estereological analysis. Hormonal restriction caused great gland involution and decreased secretory activity, aspects that were reverted by exposure to estradiol and estradiol + testosterone. However, these hormones were not able to re-establish the normal prostate histoarchitecture. The immunoreaction of steroid receptors (ER-α, ER-β, and AR) responded differently among the experimental and control groups, and PCNA assay showed a decrease in epithelial cell proliferation within groups that had hormone privation. Therefore, we conclude that estradiol and testosterone are able to influence prostate morphophysiology and the maintenance of gland homeostasis depends on a balance among these and other hormones. PMID:23529937

  20. Sex differences in adrenocortical structure and function. XVI. Stereological and karyometric studies on the cortex of the suprarenal gland of intact adult male and female Mongolian gerbils (Meriones unguiculatus).

    PubMed Central

    Malendowicz, L K

    1984-01-01

    The histological structure of intact adult male and female Mongolian gerbil (Meriones unguiculatus) suprarenal cortex has been described, and quantitative stereological and karyometric studies were performed. The weight of the gland relative to body weight was higher in female than in male gerbils, but the volume of the gland was similar in both sexes. The relative volume of the zona reticularis was higher in the female, while no sex difference was observed in the absolute volume of all suprarenal components (expressed in mm3). In all cortical zones, average cell volume was higher in the female; the nuclear volume of the zona glomerulosa and zona reticularis were also higher in the female. In the zona fasciculata, some large cells with large nuclei (greater than 210 micrometers 3) were observed. These are probably polyploid cells and have not been described in other species. The suprarenal cortex of the male gerbil contained more parenchymal cells than that of the female, the difference being dependent upon variation in the number of cells in the zona fasciculata and zona reticularis. Despite these structural differences, gland homogenates from male and female animals secreted similar amounts of cortisol and the plasma levels in the two sexes were the same. Images Fig. 1 PMID:6490533

  1. Sex differences in adrenocortical structure and function. XVI. Stereological and karyometric studies on the cortex of the suprarenal gland of intact adult male and female Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Malendowicz, L K

    1984-10-01

    The histological structure of intact adult male and female Mongolian gerbil (Meriones unguiculatus) suprarenal cortex has been described, and quantitative stereological and karyometric studies were performed. The weight of the gland relative to body weight was higher in female than in male gerbils, but the volume of the gland was similar in both sexes. The relative volume of the zona reticularis was higher in the female, while no sex difference was observed in the absolute volume of all suprarenal components (expressed in mm3). In all cortical zones, average cell volume was higher in the female; the nuclear volume of the zona glomerulosa and zona reticularis were also higher in the female. In the zona fasciculata, some large cells with large nuclei (greater than 210 micrometers 3) were observed. These are probably polyploid cells and have not been described in other species. The suprarenal cortex of the male gerbil contained more parenchymal cells than that of the female, the difference being dependent upon variation in the number of cells in the zona fasciculata and zona reticularis. Despite these structural differences, gland homogenates from male and female animals secreted similar amounts of cortisol and the plasma levels in the two sexes were the same. PMID:6490533

  2. Enterovirus 71 Infection Causes Severe Pulmonary Lesions in Gerbils, Meriones unguiculatus, Which Can Be Prevented by Passive Immunization with Specific Antisera

    PubMed Central

    Xia, Yong; Qian, Lei; Yang, Zhang-Nv; Xie, Rong-Hui; Sun, Yi-Sheng; Lu, Hang-Jing; Miao, Zi-Ping; Li, Chan; Li, Xiao; Liang, Wei-Feng; Huang, Xiao-Xiao; Xia, Shi-Chang; Chen, Zhi-Ping; Jiang, Jian-Min; Zhang, Yan-Jun; Mei, Ling-Ling; Liu, She-Lan; Gu, Hua; Xu, Zhi-Yao; Fu, Xiao-Fei; Zhu, Zhi-Yong; Zhu, Han-Ping

    2015-01-01

    Neurogenic pulmonary edema caused by severe brainstem encephalitis is the leading cause of death in young children infected by Enterovirus 71 (EV71). However, no pulmonary lesions have been found in EV71-infected transgenic or non-transgenic mouse models. Development of a suitable animal model is important for studying EV71 pathogenesis and assessing effect of therapeutic approaches. We had found neurological disorders in EV71-induced young gerbils previously. Here, we report severe pulmonary lesions characterized with pulmonary congestion and hemorrhage in a gerbil model for EV71 infection. In the EV71-infected gerbils, six 21-day-old or younger gerbils presented with a sudden onset of symptoms and rapid illness progression after inoculation with 1×105.5 TCID50 of EV71 via intraperitoneal (IP) or intramuscular (IM) route. Respiratory symptoms were observed along with interstitial pneumonia, pulmonary congestion and extensive lung hemorrhage could be detected in the lung tissues by histopathological examination. EV71 viral titer was found to be peak at late stages of infection. EV71-induced pulmonary lesions, together with severe neurological disorders were also observed in gerbils, accurately mimicking the disease process in EV71-infected patients. Passive transfer with immune sera from EV71 infected adult gerbils with a neutralizing antibody (GMT=89) prevented severe pulmonary lesion formation after lethal EV71 challenge. These results establish this gerbil model as a useful platform for studying the pathogenesis of EV71-induced pulmonary lesions, immunotherapy and antiviral drugs. PMID:25767882

  3. Combined effects of levonorgestrel and quinestrol on reproductive hormone levels and receptor expression in females of the Mongolian gerbil (Meriones unguiculatus).

    PubMed

    Lv, Xiaohui; Shi, Dazhao

    2012-01-01

    The effects of treatment with a combination of levonorgestrel and quinestrol (EP-1; ratio of 2:1) on reproductive hormone levels and the expression of their receptors in female Mongolian gerbils were examined. We show that serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) decreased, whereas serum estradiol (E2) and progesterone (P4) increased after EP-1 treatment. EP1 down-regulated mRNA expression of the follicle-stimulating hormone receptor (FSHR) and the estrogen receptor (ER) βin the ovary. EP-1 up-regulated the mRNA expression of the luteinizing hormone receptor (LHR) and the progesterone receptor (PR) in the ovary as well as ERα and PR in the uterus of Mongolian gerbils. The effects were time-dependent and dose-dependent. EP-1 had no obvious effects on ERα mRNA expression in the ovary. The current study demonstrates that the effect of EP-1 on the expression of ER subtypes is tissue-specific in Mongolian gerbils. EP-1 disrupted the reproductive endocrinology of the Mongolian gerbil. These findings suggest that the effects of EP-1 on reproductive hormone levels and their receptor expression in Mongolian gerbils may be the result of synergistic actions of levonorgestrel and quinestrol, with quinestrol playing the major role. PMID:22233494

  4. Small quantities of carotenoid-rich tropical green leafy vegetables indigenous to Africa maintain vitamin A status in Mongolian gerbils ( Meriones unguiculatus).

    PubMed

    Ejoh, Richard A; Dever, Joseph T; Mills, Jordan P; Tanumihardjo, Sherry A

    2010-06-01

    Leafy vegetables are important sources of provitamin A carotenoids. Information on their ability to provide vitamin A is often misleading because of the methodology used to assess bioefficacy. Mongolian gerbils were used to evaluate the bioefficacy of provitamin A carotenoids in tropical leafy vegetables (i.e. Solanum nigrum, Moringa oleifera, Vernonia calvoana and Hibiscus cannabinus) that are indigenous to Africa. Gerbils (n 67) were vitamin A-depleted for 5 weeks. After a baseline kill (n 7), the gerbils were weight-matched and assigned to six treatment groups (n 10; four vegetable groups; negative and positive controls). For 4 weeks, the treatments included 35 nmol vitamin A (theoretical concentrations based on 100 % bioefficacy) in the form of vegetables or retinyl acetate. In addition to their diets, the control and vegetable groups received daily doses of oil, while the vitamin A group received retinyl acetate in oil matched to prior day intake. Serum and livers were analysed for vitamin A using HPLC. Serum retinol concentrations did not differ among groups, but total liver vitamin A of the vitamin A and vegetable groups were higher than that of the negative control group (P < 0.0001). Liver beta-carotene 15,15'-monooxygenase-1 expression levels were determined for two vegetable groups and were similar to the positive and negative controls. Conversion factors for the different leafy vegetables were between 1.9 and 2.3 microg beta-carotene equivalents to 1 microg retinol. Small quantities of these vegetables maintained vitamin A status in gerbils through efficient bioconversion of beta-carotene to retinol. PMID:20412609

  5. Small quantities of carotenoid-rich tropical green leafy-vegetables indigenous to Africa maintain vitamin A status in Mongolian gerbils (Meriones unguiculatus)

    PubMed Central

    Ejoh, Richard A.; Dever, Joseph T.; Mills, Jordan P.; Tanumihardjo, Sherry A.

    2015-01-01

    Leafy vegetables are important sources of provitamin A carotenoids. Information on their ability to provide vitamin A is often misleading because of the methodology used to assess bioefficacy. Mongolian gerbils were used to evaluate the bioefficacy of provitamin A carotenoids in tropical leafy vegetables (i.e. Solanium nigrum, Moringa oleifera, Vernonia calvoana, and Hibiscus cannabinus) that are indigenous to Africa. Gerbils (n = 67) were vitamin A-depleted for 5 weeks. After a baseline kill (n = 7), the gerbils were weight-matched and assigned to 6 treatment groups (n = 10/group; 4 vegetable groups; negative and positive controls). For 4 weeks, the treatments included 35 nmol vitamin A (theoretical concentrations based on 100% bioefficacy) in the form of vegetables or retinyl acetate. In addition to their diets, the control and vegetable groups received daily doses of oil, while the vitamin A group received retinyl acetate in oil matched to prior day intake. Serum and livers were analysed for vitamin A using HPLC. Serum retinol concentrations did not differ among groups, but total liver vitamin A of the vitamin A and vegetable groups were higher than that of the negative control group (P < 0·0001). Liver β-carotene 15,15′-monooxygenase-1 expression levels were determined for two vegetable groups and were similar to the positive and negative controls. Conversion factors for the different leafy vegetables were between 1·9 and 2·3 μg β-carotene equivalents to 1 μg retinol. Small quantities of these vegetables maintained vitamin A status in gerbils through efficient bioconversion of β-carotene to retinol. PMID:20412609

  6. Synapse plasticity in motor, sensory, and limbo-prefrontal cortex areas as measured by degrading axon terminals in an environment model of gerbils (Meriones unguiculatus).

    PubMed

    Neufeld, Janina; Teuchert-Noodt, Gertraud; Grafen, Keren; Winter, York; Witte, A Veronica

    2009-01-01

    Still little is known about naturally occurring synaptogenesis in the adult neocortex and related impacts of epigenetic influences. We therefore investigated (pre)synaptic plasticity in various cortices of adult rodents, visualized by secondary lysosome accumulations (LA) in remodeling axon terminals. Twenty-two male gerbils from either enriched (ER) or impoverished rearing (IR) were used for quantification of silver-stained LA. ER-animals showed rather low LA densities in most primary fields, whereas barrel and secondary/associative cortices exhibited higher densities and layer-specific differences. In IR-animals, these differences were evened out or even inverted. Basic plastic capacities might be linked with remodeling of local intrinsic circuits in the context of cortical map adaptation in both IR- and ER-animals. Frequently described disturbances due to IR in multiple corticocortical and extracortical afferent systems, including the mesocortical dopamine projection, might have led to maladaptations in the plastic capacities of prefronto-limbic areas, as indicated by different LA densities in IR- compared with ER-animals. PMID:19809517

  7. Streptococcus merionis sp. nov., isolated from Mongolian jirds (Meriones unguiculatus).

    PubMed

    Tappe, Dennis; Pukall, Rüdiger; Schumann, Peter; Gronow, Sabine; Spiliotis, Markus; Claus, Heike; Brehm, Klaus; Vogel, Ulrich

    2009-04-01

    Gram-positive, catalase-negative, chain-forming, coccus-shaped organisms were isolated both from intraperitoneally grown vesicles of the fox tapeworm Echinococcus multilocularis and the oropharynges of laboratory-kept Mongolian jirds (Meriones unguiculatus). The strains displayed no haemolytic activity on Columbia sheep blood agar, pyrrolidonyl arylamidase activity was negative and the organisms reacted weakly with Lancefield group D antiserum. On the basis of phenotypic characteristics, the strains were tentatively identified as members of the genus Streptococcus. Comparative 16S rRNA gene sequencing studies confirmed their assignment to the genus Streptococcus and revealed that Streptococcus hyointestinalis DSM 20770(T) was their closest phylogenetic neighbour (96.5 % sequence similarity). The levels of 16S rRNA gene sequence similarity between the isolates and representatives of species of the genus Streptococcus were only 95.7-96.2 %. On the basis of the phenotypic and molecular data presented, the isolates from Mongolian jirds represent a novel species of the genus Streptococcus, for which the name Streptococcus merionis sp. nov. is proposed. The type strain is WUE3771(T) (=DSM 19192(T)=CCUG 54871(T)). PMID:19329603

  8. Hesperidin increases intestinal β,β-carotene 15-15' mono-oxygenase 1 (BCMO1) activity in Mongolian gerbils (Meriones unguiculatus) fed with β-carotene-free diet.

    PubMed

    Poulaert, Marie; Gunata, Ziya; During, Alexandrine; Reboul, Emmanuelle; Laurent, Caroline; Gaillet, Sylvie; Dhuique-Mayer, Claudie

    2014-09-15

    β,β-Carotene 15-15' mono-oxygenase 1 (BCMO1) is a key enzyme in vitamin A (VitA) metabolism in mammals. Dietary compounds, such as carotenoids and polyphenols, were reported to influence BCMO1 activity. The aim of this study was to evaluate the effect of hesperidin (Hes), on the VitA bioefficacy of β-carotene (Bc) from orange-fleshed sweet potato, using Mongolian gerbils, focussing on BCMO1 activity. Gerbils (n=50) depleted in VitA were divided into five groups fed with basal diet containing 3% white- or orange-fleshed sweet potatoes supplemented or not with Hes. Liver BCMO1 activity was low, with no significant differences between groups. Interestingly, intestinal mucosal BCMO1 activity was significantly higher in the gerbils fed without Bc or VitA than those fed with a VitA/Bc-supplemented diet. Finally, our results show that, under a low VitA status, Hes dramatically stimulated intestinal BCMO1 activity, an effect that could possibly be related to its action as an agonist of PPARγ. PMID:24767085

  9. Probing the spatial cluster of Meriones unguiculatus using the nest flea index based on GIS technology.

    PubMed

    Zhuang, Dafang; Du, Haiwen; Wang, Yong; Jiang, Xiaosan; Shi, Xianming; Yan, Dong

    2016-11-01

    The nest flea index of Meriones unguiculatus is a critical indicator for the prevention and control of plague, which can be used not only to detect the spatial and temporal distributions of Meriones unguiculatus, but also to reveal its cluster rule. This study used global spatial autocorrelation and spatial hot spot detection methods to describe the relationship between different years and the autocorrelation coefficient of nest flea indexes; it also used a spatial detection method and GIS technology to detect the spatial gathered hot spot of Meriones unguiculatus in the epidemic areas. The results of this study showed that (1) there were statistically significant spatial autocorrelations in the nest flea indexes in 2006, 2012, 2013 and 2014. (2) Most of the distribution patterns of Meriones unguiculatus were statistically significant clusters of high values. (3) There were some typical hot spot regions of plague distributed along the Inner Mongolia plateau, north of China. (4) The hot spot regions of plague were gradually stabilized after increasing and decreasing repeatedly. Generally speaking, the number of hot spot regions showed an accelerated increase from 2005 to 2007, decreased slowly from 2007 to 2008, rapidly increased again after decreasing slowly from 2008 to 2010, showed an accelerated decrease from 2010 to 2011, and ultimately were stabilized after rapidly increasing again from 2011 to 2014. (5) The migration period of the hot spot regions was 2-3 years. The epidemic area of plague moved from southwest to east during 2005, 2007, 2008 and 2010, from east to southwest during 2007 and 2008, from east to west during 2010 and 2011, and from Midwest to east during 2011 and 2014. (6) Effective factors, such as temperature, rainfall, DEM, host density, and NDVI, can affect the spatial cluster of Meriones unguiculatus. The results of this study have important implications for exploring the temporal and spatial distribution law and distribution of the hot spot

  10. [Interactions of partners in family pairs, care of the offspring, and the role of tactile stimulation in formation of parental behavior of the Mongolian gerbil (Meriones unguiculatus) under laboratory conditions].

    PubMed

    Gromov, V S

    2009-01-01

    The interactions of sexual partners and care of the offspring in male and female Mongolian gerbils reared in biparental and uniparental family groups (without an adult male) were compared. In individuals reared in biparental family groups, sexual differences related to the manifestation of parental care were small and statistically insignificant. In individuals reared in uniparental groups, the interactions of sexual partners related to grooming changed; the duration in males decreased threefold, as compared to the norm; indices of parental behavior of females and, especially of males, related to tactile stimulation of pups (huddling with pups in the nest and duration of licking pups) also decreased. The importance of the parental contribution of males, especially of tactile stimulation, in the evolution of the family-group mode of life is discussed. PMID:19899220

  11. DETERMINATION OF GIARDIA LAMBLIA CYST INFECTIVE DOSE FOR THE MONGOLIAN GERBIL (MERIONES UNQUICULATUS)

    EPA Science Inventory

    The purpose of this study was to determine the I.D.50 for Giardia lamblia (CDC:0284:1) cysts in Mongolian gerbils (Meriones unquiculatus) and compare it to human infectivity data. ysts were purified from Mongolian gerbil feces and diluted to produce inocula for each dosage group....

  12. Therapeutic Value of Ginkgo biloba Extract EGb 761® in an Animal Model (Meriones unguiculatus) for Noise Trauma Induced Hearing Loss and Tinnitus.

    PubMed

    Krauss, Patrick; Tziridis, Konstantin; Buerbank, Stefanie; Schilling, Achim; Schulze, Holger

    2016-01-01

    Noise induced hearing loss (NIHL) is a common disease in modern societies and may lead to maladaptations within the auditory system that finally result in subjective tinnitus. Available therapies may only alleviate the symptoms rather than restore normal hearing. In a previous study we demonstrated that the prophylactic application of Ginkgo biloba extract EGb 761® significantly reduces NIHL and tinnitus development in our Mongolian gerbil (Meriones unguiculatus) animal model. Here, we tested whether the application of EGb 761® has beneficial effects after the formation of permanent NIHL and tinnitus. To this end we monitored the therapeutic effects of EGb 761® on noise trauma-induced changes in signal processing within the auditory system of our animal model by behavioral (acoustic startle response, ASR) and electrophysiological approaches (auditory brainstem responses, ABR). We found that-in contrast to vehicle-three weeks of daily oral EGb 761® treatment (100 mg/kg body weight) led to a restoration of hearing thresholds back to pre-trauma conditions. In addition, all 9 animals that displayed behavioral signs of subjective tinnitus showed improvement, with 7 of them showing complete relief of tinnitus symptoms during the time of EGb 761® treatment. After discontinuation of EGb 761® treatment, tinnitus related behavior reappeared in all but one of these animals while auditory thresholds remained restored. A detailed analysis of ABR waves revealed that EGb 761® treatment did not simply change auditory processing back to pre-trauma conditions, but led to subtle changes of ABR wave amplitude and latency at different levels of the auditory pathway, with an overall increase of response to low stimulus intensities and a decrease at high intensities. The functional relevance of these changes may be the observed improvement of hearing thresholds while at the same time suppression of responses to high stimulus intensities may point to a global inhibitory mechanism

  13. Therapeutic Value of Ginkgo biloba Extract EGb 761® in an Animal Model (Meriones unguiculatus) for Noise Trauma Induced Hearing Loss and Tinnitus

    PubMed Central

    Buerbank, Stefanie; Schilling, Achim; Schulze, Holger

    2016-01-01

    Noise induced hearing loss (NIHL) is a common disease in modern societies and may lead to maladaptations within the auditory system that finally result in subjective tinnitus. Available therapies may only alleviate the symptoms rather than restore normal hearing. In a previous study we demonstrated that the prophylactic application of Ginkgo biloba extract EGb 761® significantly reduces NIHL and tinnitus development in our Mongolian gerbil (Meriones unguiculatus) animal model. Here, we tested whether the application of EGb 761® has beneficial effects after the formation of permanent NIHL and tinnitus. To this end we monitored the therapeutic effects of EGb 761® on noise trauma-induced changes in signal processing within the auditory system of our animal model by behavioral (acoustic startle response, ASR) and electrophysiological approaches (auditory brainstem responses, ABR). We found that–in contrast to vehicle–three weeks of daily oral EGb 761® treatment (100 mg/kg body weight) led to a restoration of hearing thresholds back to pre-trauma conditions. In addition, all 9 animals that displayed behavioral signs of subjective tinnitus showed improvement, with 7 of them showing complete relief of tinnitus symptoms during the time of EGb 761® treatment. After discontinuation of EGb 761® treatment, tinnitus related behavior reappeared in all but one of these animals while auditory thresholds remained restored. A detailed analysis of ABR waves revealed that EGb 761® treatment did not simply change auditory processing back to pre-trauma conditions, but led to subtle changes of ABR wave amplitude and latency at different levels of the auditory pathway, with an overall increase of response to low stimulus intensities and a decrease at high intensities. The functional relevance of these changes may be the observed improvement of hearing thresholds while at the same time suppression of responses to high stimulus intensities may point to a global inhibitory

  14. Water intake after stomach loads of NaCl in Mongolian gerbils.

    PubMed

    Kozub, F J; Hodges, J; Yutzy, S

    1980-10-01

    Sixty mongolian gerbils (Meriones unguiculatus), 30 male and 30 female, were stomach loaded (2% b.w.) with either water or .9, 2, 6, 10, or 12% NaCl (wt x vol.). Unlike male rats, male gerbils did not lose weight. Female gerbils, like female rats, did not lose weight. However, female gerbils did not increase their water intake at any concentration, whereas males increased their water intake only at the 10 and 12% levels. These data are very much unlike those for the rat (male and female) which show an increase in water intake in response to NaCl solutions above isotonicity. PMID:7441220

  15. ß-Carotene from Red Carrot Maintains Vitamin A Status, but Lycopene Bioavailability Is Lower Relative to Tomato Paste in Mongolian Gerbils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red carrots contain lycopene in addition to ß-Carotene. The utility of red carrot as a functional food depends in part on the bioavailability of its constituent carotenoids. Lycopene bioavailability was compared in Mongolian gerbils (Meriones unguiculatus) fed freeze-dried red carrot and tomato pa...

  16. Recurrent Inhibition to the Medial Nucleus of the Trapezoid Body in the Mongolian Gerbil (Meriones Unguiculatus)

    PubMed Central

    Dondzillo, Anna; Thompson, John A.; Klug, Achim

    2016-01-01

    Principal neurons in the medial nucleus of the trapezoid body (MNTB) receive strong and temporally precise excitatory input from globular bushy cells in the cochlear nucleus through the calyx of Held. The extremely large synaptic currents produced by the calyx have sometimes led to the view of the MNTB as a simple relay synapse which converts incoming excitation to outgoing inhibition. However, electrophysiological and anatomical studies have shown the additional presence of inhibitory glycinergic currents that are large enough to suppress action potentials in MNTB neurons at least in some cases. The source(s) of glycinergic inhibition to MNTB are not fully understood. One major extrinsic source of glycinergic inhibitory input to MNTB is the ventral nucleus of the trapezoid body. However, it has been suggested that MNTB neurons receive additional inhibitory inputs via intrinsic connections (collaterals of glycinergic projections of MNTB neurons). While several authors have postulated their presence, these collaterals have never been examined in detail. Here we test the hypothesis that collaterals of MNTB principal cells provide glycinergic inhibition to the MNTB. We injected dye into single principal neurons in the MNTB, traced their projections, and immunohistochemically identified their synapses. We found that collaterals terminate within the MNTB and provide an additional source of inhibition to other principal cells, creating an inhibitory microcircuit within the MNTB. Only about a quarter to a third of MNTB neurons receive such collateral inputs. This microcircuit could produce side band inhibition and enhance frequency tuning of MNTB neurons, consistent with physiological observations. PMID:27489949

  17. Effects of artemisinin and Artemisia annua extracts on Haemonchus contortus in gerbils (Meriones unguiculatus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Haemonchus contortus is a blood-sucking abomasal parasite of small ruminants that is responsible for major losses to producers worldwide. Resistance of this nematode to commercial anthelmintics has produced a demand for alternative control methods. Artemisia annua is the sole commercial source of ...

  18. Presence of cerium-cytochemical reactions of glomerular phosphatases of normal gerbil Meriones crassus: an ultrastructural localization study.

    PubMed

    Safer, A M; Abou-Salem, K

    1997-03-01

    Phosphatase cytochemical activity in the normal glomerulus of the desert gerbil Meriones crassus was demonstrated using cerium ions as capturing agents. Three major enzymes have been recognized: sodium-potassium adenosine triphosphatase (Na(+)-K(+)-ATPase), alkaline phosphatase (ALPase) and acid phosphatase (ACPase). However, cytochemical staining for these markers to map their localizations and distributions reveal a high positivity of Na(+)-K(+)-ATPase. This appeared as uniform dense precipitates surrounding the glomerular basement membrane (GBM) and the plasma membranes of the epithelial and endothelial cells of the glomerular layers. Negligible ALKase reaction product being over the glomerular epithelia including the GBM. In contrast, the cytochemical profiles of ACPase was unusual, with dense reaction products extensively covering the endoplasmic reticulum at the region of Golgi apparatus products lysosomes (GERL) complex, including its cisternal and tubular elements and the lysosomal-vacuolar apparatus of the glomerular epithelial cells. All other subcellular organelles showed no activity. For Na(+)-K(+)-ATPase, the reaction product was successive when acetate buffer (as decalcifying agent, pH 5.0) was used. This reaction was still seen when a medium containing levamisole was used. Cytochemical controls for all enzymes were incubated in substrate-free media including those using levamisole as an inhibitor of ALPase. The data presented, which is reported for the first time, is not an attempt to determine the contribution of the selected phosphatases in the glomerular physiology and pathology. Such findings may, nevertheless, have functional implications in the fact that these markers may be involved in the ultrafiltration and other metabolic activities of the glomerulus at the molecular and/or cellular level. In addition to earlier morphological and recent histochemical work, the present study updates and recognizes information to be used as a baseline to

  19. Water intake after stomach loads of NaCl in 30-, 40-, and 50-day-old Mongolian gerbils.

    PubMed

    Kozub, F J; Brown, B

    1982-10-01

    Ninety Mongolian gerbils (Meriones unguiculatus), 15 male and 15 female in each of three age groups (30-, 40-, and 50-day-old), were stomach loaded with either water, 6% NaCl, or 12% NaCl (wt./vol.). No differences were observed in fluid intake or in body weight 24 hours after the load. These data were totally unlike the findings in rats. The lack of intergroup differences were probably attributable to the gerbil's unusual adrenal and kidney structure and hormonal controls. PMID:7175508

  20. Long-term effect of vasectomy on the biochemical composition of testes and sex accessory organs of the Indian desert gerbil, Meriones hurrianae Jerdon.

    PubMed

    Lohiya, N K; Dixit, V P

    1975-02-01

    A long-term vasoligation operation in gerbils, Meriones hurrianae Jerdon did not reveal any consistent change in the weights of androgen dependent organs such as seminal vesicles, ventral prostate, epididymes and perineal complex (levator ani muscle and penis). Histological structure of the testis and caput epididymis remains normal after vasectomy. There was no effect of bilateral vasectomy on androgen production of the testes as reflected by fructose content of coagulating gland. No compensatory hypertrophy of the contralateral testis was observed in unilaterally vasectomized gerbils. The RNA content of the testis and epididymis and ascorbic acid content of adrenal gland did not show appreciable change. No change in protein content of the testis was found but a significant increase was observed in the protein content of epididymis after the operation. PMID:1175529

  1. Contextual processing of brightness and color in Mongolian gerbils.

    PubMed

    Garbers, Christian; Henke, Josephine; Leibold, Christian; Wachtler, Thomas; Thurley, Kay

    2015-01-01

    Brightness and color cues are essential for visually guided behavior. However, for rodents, little is known about how well they do use these cues. We used a virtual reality setup that offers a controlled environment for sensory testing to quantitatively investigate visually guided behavior for achromatic and chromatic stimuli in Mongolian gerbils (Meriones unguiculatus). In two-alternative forced choice tasks, animals had to select target stimuli based on relative intensity or color with respect to a contextual reference. Behavioral performance was characterized using psychometric analysis and probabilistic choice modeling. The analyses revealed that the gerbils learned to make decisions that required judging stimuli in relation to their visual context. Stimuli were successfully recognized down to Weber contrasts as low as 0.1. These results suggest that Mongolian gerbils have the perceptual capacity for brightness and color constancy. PMID:25589297

  2. Effects of chemical occlusion of vas deferens on the reproductive organs in gerbil Meriones hurrianae Jerdon.

    PubMed

    Dixit, V P; Agrawal, M; Jain, H C

    1976-09-01

    Male gerbils were sterilized by giving a single injection of a sclerosing chemicial (5% KMnOH) directly into the vasa. After 3 weeks the gerbils were killed. Testes, accessory sex organs, and thyroid and adrenal glands were removed and weighed. Halves of testis and epididymides were fixed in Bouin's fluid fo r microscopic study. The remaining halves were frozen and total RNA, protein, sialic acid, seminal vasicular fructose, and testicular lipids were later determined. Cholesterol estimations were also made. 2 weeks following vas injections animals were tested by exposing them to cycling estrous females. 21 days later the females were examined for possible implantation sites. It was shown that the males had been sterile. Weights of testicles, accessory sex organs, thyroid and adrenal gland remained normal, except that there was a significant increase in the weight of the ventral prostate. No histological changes were found in the testes. Protein content of the testes, epididymides, and seminal vesicles did not change. A decrease in RNA was noted. Sialic acid levels did not alter. Cholesterol and total lipids were normal. Alkaline phosphatase activity in the testes and epididymides had not changed after 3 weeks. Vasicular fructose was normal. Complete occlusion of the vasa resulted. After 100 days there was no return to fertility. The results appear to be permanent. PMID:1024985

  3. Refinement of gerbil housing and husbandry in the laboratory.

    PubMed

    Waiblinger, Eva; König, Barbara

    2004-06-01

    Mongolian gerbils, Meriones unguiculatus, are widely used as model species in parasitology, and in research on epilepsy and ischaemia. When kept under standard laboratory housing conditions, gerbils develop two distinctive behavioural abnormalities: stereotypic digging and bar chewing. Our work centred on assessing the mechanisms leading to these stereotypies. We aimed at finding practical housing and husbandry solutions that would prevent the development of such stereotypies in the laboratory by addressing the behavioural needs of gerbils. Faecal cortisol levels were used as a non-invasive method to compare stress reactions in gerbils housed under different conditions. Stereotypic digging was caused by the lack of a burrow in the laboratory cage, while stereotypic bar chewing was caused by premature separation of juveniles from their family before the birth of younger siblings. An integrated artificial burrow system is presented that prevents the development of stereotypic digging in gerbils, and adaptations in husbandry routines are suggested that significantly reduce the incidence of bar chewing. We conclude that simple refinement of housing is effective in improving gerbil welfare in the laboratory. PMID:23577453

  4. Experimental endocrine therapies promote epithelial cytodifferentiation and ciliogenesis in the gerbil female prostate.

    PubMed

    Santos, Fernanda Cristina Alcântara; Falleiros-Júnior, Luiz Roberto; Corradi, Lara Silvia; Vilamaior, Patricia Simone Leite; Taboga, Sebastião Roberto

    2007-06-01

    The incidence of ciliated cells in the prostate gland of the female gerbil (Meriones unguiculatus) is uncommon and apparently becomes more frequent during androgen (testosterone cypionate) and anti-estrogen (letrozole) endocrine therapies. To evaluate the effects of such drug therapies on the induction of ciliogenesis in the glandular epithelium of female prostate glands, adult female gerbils aged 90 days were treated for 14 days with testosterone and letrozole after which their prostate glands were removed for histological, ultrastructural, and serological analyses. The cytodifferentiation of the ciliated phenotype in the alveolar epithelium became more frequent after both the testosterone and the letrozole treatments. The ciliogenesis phenomenon of the epithelial cells in the prostate gland of female gerbils thus appears to be induced by variations in the increase of androgen levels. PMID:17347814

  5. [Comparative analysis of structural and functional characteristics of soleus muscle in rats and Mongolian gerbils during gravitational unloading of various duration].

    PubMed

    Ogneva, I V; Kurushin, V A; Glashev, M M; Mikhaĭlova, E V; Ponomareva, E V; Altaeva, E G; Krivoĭ, I I; Shenkman, B S

    2010-01-01

    A comparative investigation of the dynamics of contractile properties of the whole soleus muscle and its fibers during 3- and 12-day-long hind limb suspension of Wistar rats and Mongolian gerbils (Meriones unguiculatus) has been performed. The data obtained indicate that the structural and functional changes caused by hypogravity in gerbils are slowed down compared with rats. A very intensive drop in water containment in gerbils was found, which can cause shifts in the ionic strength of the intracellular space of the muscle fiber. As a result, the photolytic activity of different enzymes may change, which can induce a less pronounced reduction in Z-disc and M-line stiffness and contractile capabilities in gerbils compared to rats. PMID:21268358

  6. An assessment of behavioral aging in the Mongolian gerbil.

    PubMed

    Spangler, E L; Hengemihle, J; Blank, G; Speer, D L; Brzozowski, S; Patel, N; Ingram, D K

    1997-01-01

    Male Mongolian gerbils (Meriones unguiculatus) 14-54 months old (n = 77) were evaluated in a battery of psychomotor (open field, locomotor, and runwheel activity, rotorod performance) and learning (one-way active avoidance in a straight runway and in 14-unit T-maze performance) tests. Body weight and seizure activity were also monitored. According to linear regression analysis, runwheel activity decreased with age; and the number of errors in the 14-unit T-maze increased as a function of age (ps < 0.05). None of the other behavioral measures or body weight were significantly correlated with age. This gerbil strain (Tumblebrook Farms; West Brookfield, MA) tended to be very prone to seizures with 64% of the gerbils experiencing at least one seizure while being tested. Seizures tended to occur when the gerbil was exposed to a novel situation (e.g., initial weighing, placement on the rotorod). An age-related decline in some aspects of psychomotor and learning performance was observed, suggesting the gerbil as an additional mammalian model of aging. The high incidence of seizure activity presented a complicating and confounding variable to the interpretation of the results of the behavioral tests used in the present study. Interventions to control seizure activity (e.g., systematic, controlled breeding; adaptation to apparati) in this model will likely increase its viability as a mammalian model of aging. PMID:9785096

  7. Effect of long-term administration of melatonin on adrenal histomorphology of the Indian desert gerbil Meriones hurrianae Jerdon.

    PubMed

    Joshi, B N; Sujathakumari, M

    1995-11-01

    Melatonin treatment for 8 weeks resulted in a significant increase (P < 0.01) in weights of the adrenal glands, in both male and female, M. hurrianae. The weight increase was not related to the time of administration of melatonin. Histology of adrenal glands in melatonin treated gerbils revealed a stimulatory response. In treated gerbils, adrenal cortex exhibited significant hypertrophy with enlarged nuclei and degranulated cytoplasm. Signs of hypertrophy were also evident in the adrenal medulla. The physiological significance of this response is not yet clear. It remains to be clarified if the hypertrophy indicates enhanced synthesis of corticosteroids. PMID:8786156

  8. Salt and stress synergize H. pylori-induced gastric lesions, cell proliferation, and p21 expression in Mongolian gerbils.

    PubMed

    Gamboa-Dominguez, Armando; Ubbelohde, Tom; Saqui-Salces, Milena; Romano-Mazzoti, Luis; Cervantes, Minerva; Domínguez-Fonseca, Claudia; de la Luz Estreber, Maria; Ruíz-Palacios, Guillermo M

    2007-06-01

    Our aim was to determine if salt and stress enhance Helicobacter pylori (Hp) lesions in Meriones unguiculatus. Two hundred seventy-eight pathogen-free gerbils were allocated to seven groups: Hp-Sydney strain (45), 8% higher-salt diet (38), stress (60% space reduction/water immersion; 36), Hp + salt (33), Hp + stress (34), N-methyl-N-nitro-N-nitrosoguanidine (34), and sham (58). Gerbils were sacrificed at 1 week (67), 12 weeks (73), 52 weeks (65), and 68 weeks (73). Sydney, Padova, and Lauren classifications were blindly used. Proliferation, p53, p21, and apoptosis were assessed. Follicular active gastritis (grade 2/3) was observed in 10% of Hp gerbils, 38% of Hp + salt gerbils, and 29% of Hp + stress gerbils at 52 weeks and 67%, 83%, and 43% at 68 weeks (P < 0.05). Heterotopic proliferative glands were identified in synergy groups from 52 weeks, with increases in their number and size by 68 weeks. Higher proliferative rates were observed in Hp+salt gerbils (P < 0.0001), and p21 overexpression in Hp+salt and Hp+stress gerbils (both P's < 0.0001), by 68 weeks, without p53 increases. We conclude that salt and stress synergize Hp damage and increase pseudo-invasive gland foci. PMID:17404882

  9. Indigenous nasopharyngeal, auditory canal, and middle ear bacterial flora of gerbils: animal model for otitis media.

    PubMed Central

    Thompson, T A; Gardner, D; Fulghum, R S; Daniel, H J; Allen, W E; Worthington, J M; Williams, P P

    1981-01-01

    The indigenous microbial flora of the middle ear cavity of Mongolian gerbils, Meriones unguiculatus, was isolated, characterized, and identified, showing it to be sparse and transitory. Organisms, when found in the middle ear cavity, were most likely to be Staphylococcus epidermidis-like organisms. Cerumen from the external auditory canal of these animals yielded mostly staphylococci, coryneforms, and other gram-positive rods, including some anaerobic species. The nasopharynx supported a flora consisting mainly of staphylococci, lactobacilli, and coryneforms, with a smaller incidence and numbers of many other species. No mycoplasmas were cultured or seen in scanning electron microscope studies. None of the major pathogens of human otitis media were found; therefore, Mongolian gerbils are microbiologically acceptable candidates as a model for induced otitis media, using organisms isolated from human otitic infections. PMID:7251160

  10. Effects of levonorgestrel-quinestrol (EP-1) treatment on Mongolian gerbil wild populations: a case study.

    PubMed

    Fu, Heping; Zhang, Jinwei; Shi, Dazhao; Wu, Xiaodong

    2013-09-01

    Rodent pest population outbreaks occur frequently in grassland ecosystems in northern China. The Mongolian gerbil (Meriones unguiculatus) is a dominant pest rodent which is distributed across the semi-desert grasslands of Inner Mongolia, China. In 2009, we studied the contraceptive effect of levonorgestrel-quinestrol (EP-1), concentration 50 ppm, on a wild Mongolian gerbil population. The one-off contraceptive treatment was compared with a control group using a semi-monthly live trapping method in the Ordos Semi-desert Grassland Region of Inner Mongolia. The results show that juveniles were not recruited in spring in the treatment group. Ratios of juveniles in the control and treatment groups showed significant semi-monthly differences from spring to summer (one-way ANOVA, F2, 14 = 7.53, P < 0.05). Between both groups, annual fluctuations of juvenile and total population densities were significantly different respectively (F2, 14 = 4.64, P < 0.05; F2, 18 = 7.72, P < 0.05). The contraceptive EP-1 delayed the normal reproductive pattern of Mongolian gerbil populations. This suppressed birth rates of gerbil populations, reduced their densities, and changed their age structures. The period of EP-1 baiting should be extended but it could be an ideal method for controlling Mongolian gerbil populations during each breeding season. PMID:24020466

  11. Technical note for post-auricular route surgery in Mongolian gerbil.

    PubMed

    Risoud, Michaël; Bonne, Nicolas-Xavier; Fourdrinier, Martin; Hubert, Thomas; Vincent, Christophe

    2016-07-01

    The Mongolian gerbil (Meriones unguiculatus) is commonly used in hearing research because the hearing frequency spectrum of the gerbil is rather similar to that of the human being. However, a precise description of the surgical post-auricular route has not been reported. The aim of this technical note is to provide details on the procedure and the surgical anatomy of the post-auricular route in the Mongolian gerbil. Surgery was performed under general anesthesia on eight (2 males and 6 females) adult Mongolian gerbils. All steps of the post-auricular route were detailed. This surgery provided an access to the following structures: the semi-circular posterior and lateral canals, the external auditory meatus, the tympanic membrane, the round window, the stapes, the stapedial artery and the reliefs of the cochlea. No anatomic variation was noticed among the 8 animals. This post-auricular route in the Mongolian gerbil defines a brief and simple surgery, overall standardized as a consequence of the absence of common anatomic variation, with painless and uncomplicated post-operative stage. PMID:27244698

  12. The perforant path in the seizure sensitive gerbil contains the Ca(2+)-binding protein parvalbumin.

    PubMed

    Scotti, A L; Nitsch, C

    1991-01-01

    The Mongolian gerbil (Meriones unguiculatus) is used as a model in epilepsy studies. Structural abnormalities in the hippocampus and in its GABAergic system have been correlated with this affliction. A reliable marker of a subpopulation of GABAergic neurons is the Ca2+ binding protein parvalbumin (PV). Here we show that, whereas PV is present in the same population of hippocampal interneurons in gerbil as described in the rat, in the gerbil, PV-immunoreactivity is also found in the outer molecular layer of the hippocampus. Ultrastructural analysis revealed that it is located there in axospinous boutons with asymmetric synaptic junctions, i.e. the terminals of the entorhinal perforant path. Upon ablation of the intensely PV-immunoreactive entorhinal cortex, PV-staining is completely absent in its hippocampal termination zones. Thus, in gerbil hippocampus (but not in the rat, mouse, cat and man) PV is contained in a presumably excitatory projection. This outstanding feature of the limbic system of the gerbil implies different functional properties related to Ca2+ mediated processes, and could be of relevance for the seizure sensitivity of this animal species. PMID:1884754

  13. [Development of chow for Mongolian gerbils suitable for the conditions of space flight].

    PubMed

    Soldatov, P E; Mednikova, E I; Solov'eva, Z O; Gur'eva, T S; Dadasheva, O A; Il'in, V K; Lysenko, L A

    2008-01-01

    One of formidable issues of experiments with animals in space flight is water supply. For Mongolian gerbils (Meriones unguiculatus), classed as cricetid rodents, water in chow is enough. These animals are a new object for space biology. Our purpose was to compose a full-value formula and design a chow making and long-term storage technology to provide Mongolian gerbils for in microgravity. The chow is required to have a 28-d shelf life. To assess the chow suitability on autonomous space fight, the gerbils we house in a cage with the geometry reproducing the current design of the future space animal module. The assessment was performed with adult male gerbils weighing 50.5 +/- 3.4 g on the average. The animals ate up 40.1 +/- 3.9%, i.e. less than 50% of the feed all through the period of experiment. However, by the end of the experiment the body mass and exterior remained essentially unchanged In was concluded that the chow formula can be prescribed to Mongolian gerbils housed in self-contained modules. PMID:19055016

  14. Identification of Giardia lamblia-specific antigens in infected human and gerbil feces by western immunoblotting.

    PubMed Central

    Stibbs, H H; Samadpour, M; Ongerth, J E

    1990-01-01

    Western immunoblot analysis of aqueous extracts of feces obtained from five giardiasis patients and from experimentally infected gerbils (Meriones unguiculatus) with rabbit antiserum to Giardia lamblia cysts has revealed antigens of three molecular weight groups. A stepladderlike, evenly-spaced set of strongly reactive antigens (darkest at a molecular weight [m.w.] of 55,000 to 70,000) appeared in the gerbil feces from day 4 (first experiment) or day 2 (second experiment) and lasted to about day 7 but disappeared completely by day 8 and did not reappear later. These antigenic bands were seen in gerbils infected with two isolates of G. lamblia. These bands were not revealed when antiserum to trophozoites was used as the probe, nor were they evident in specimens from the patients or in a preparation of sonicated cysts. A second group of antigens, represented by two to three low-m.w. bands of approximately 15,000 to 20,000, was evident in both the blots of gerbil feces after approximately day 8 and the specimens from the giardiasis patients. The third group of antigens revealed by blotting experiments was a high-m.w. band (approximately 110,000) which appeared on a number of days (beginning of day 8 of gerbil infection), but this band was not seen in the human specimens. A clear band corresponding to the previously reported GSA-65 antigen was not seen in either the gerbil or the human samples. Some low- and high-m.w. bands were also detected by antitrophozoite serum in the gerbil samples, but these were weak and unimpressive compared with those visualized using anticyst serum. A monoclonal antibody-based antigen capture enzyme-linked immunosorbent assay revealed that Giardia spp.-specific stool antigen rose suddenly at day 3 of gerbil infection, at the time when fecal cyst numbers began to rise rapidly. Images PMID:2229361

  15. Efficacy of an orange oil emulsion as an anthelmintic against Haemonchus contortus in gerbils (Meriones unguiculatus) and in sheep (Ovis aries)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Haemonchus contortus is a blood-sucking abomasal parasite responsible for major losses to small ruminant producers worldwide. The recent increase in populations of anthelmintic resistant parasites has produced a demand for alternative control methods. An orange oil emulsion that has shown activity...

  16. Maize genotype and food matrix affect the provitamin A carotenoid bioefficacy from staple and carrot-fortified feeds in Mongolian gerbils (Meriones unguiculatus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofortification of staple crops to increase provitamin A carotenoids is a promising technique to alleviate vitamin A deficiency. ß-Carotene (ßC) and ß-cryptoxanthin (ßCX) are low in typical maize but higher in biofortified varieties. In vitro screening methods evaluate bioaccessibility of carotenoi...

  17. Corticofugal Modulation of DPOAEs in Gerbils.

    PubMed

    Jäger, K; Kössl, M

    2016-02-01

    Efferent auditory feedback on cochlear hair cells is well studied regarding olivocochlear brainstem mechanisms. Less is known about how the descending corticofugal system may shape efferent feedback and modulate cochlear mechanics. Distortion-product otoacoustic emissions (DPOAEs) are a suitable tool to assess outer hair cell function, as they are by-products of the nonlinear cochlear amplification process. The present project investigates the effects of cortical activity on cubic and quadratic DPOAEs in mongolian gerbils, Meriones unguiculatus, through cortical deactivation using the sodium-channel blocker lidocaine. Contralateral cortical microinjections of lidocaine can lead to either an increase or decrease of median DPOAE levels of up to 10.95 dB. The effects are reversible and comparable at all tested frequencies (0.5-40 kHz). They are not restricted to the preferred frequency of the cortical site of injection. Recovery times are between 20 and 120 min depending on stimulation levels and emission type. When the injection is performed in the ipsilateral hemisphere, DPOAE level shifts are lower in amplitude compared to those after injection in the contralateral hemisphere. No significant changes in DPOAE levels are obtained after saline microinjections. Results indicate that deactivation of auditory cortex activity through lidocaine has a considerable impact on peripheral auditory responses in form of DPOAEs, probably through cortico-olivocochlear pathways. PMID:26619750

  18. Hormones orchestrated pre- and post-copulatory sexual traits in male Mongolian gerbils.

    PubMed

    Shen, Wei; Zhang, Xue-Ying; Liu, Ding-Zhen; Wang, De-Hua

    2015-05-01

    Parker's sperm competition model predicts a negative relationship between pre-copulatory (social status) and post-copulatory (sperm quality and quantity) sexually selected traits, however, empirical studies have revealed considerable inconsistency in this relationship. We hypothesized that there was a trade-off between pre- and post-copulatory sexually selected traits, and hormones (corticosterone, CORT; testosterone, T) orchestrate this relationship. In this study, we measured energetic parameters in the dominant-subordinate Mongolian gerbils (Meriones unguiculatus), whose relationship was established under chronic social encounters in a neutral arena, and then tested the relationship between their social status and sperm quality and quantity. Our results showed that dominant males initiated attack sooner and displayed more aggression, self-grooming and locomotion behaviors in daily social encounters across seven consecutive days. Dominant gerbils also had more and better quality of sperm than that of subordinate males, yet showed no significant differences in energy intake and RMR in comparison with subordinate individuals. In addition, dominant males had higher concentrations of serum T than subordinate males, whereas the concentrations of CORT showed a reverse pattern. The frequency and duration of aggression (indicative of social status) increased with elevated T concentrations. Sperm quality in terms of number and activity were associated with higher concentrations of serum T in dominant gerbils, whereas small sperm counts and poor-quality sperm were associated with relatively higher concentrations of serum CORT in subordinate gerbils. Together, our data indicated that there was no trade-off between pre- and post-copulatory sexually selected traits but hormones orchestrated the relationship between these traits in male Mongolian gerbils. PMID:25725121

  19. Effects of Malva viscus conzattii Greenm flower extract on testicular function of the house rat Rattus rattus Rufescens & the gerbil Meriones hurrianae Jerdon: a biochemical study.

    PubMed

    Dixit, V P

    1977-07-01

    Extract of the flower Malva viscus conzattii (M. conzattii) was administered at a dose of 25/50 mg/day/animal to 30 healthy adult male gerbils and 30 adult male house rats to determine its effect on fertility. After 25 days' treatment fin l body weight, and the weights of testes, epididymides, seminal vesicles, and adrenal glands were measured. Testis, epididymides, and seminal vesicles were prepared for histological examination and total protein, RNA, sialic acid, and alkaline phosphatase activity were determined. Quantitative estimation of cholesterol was also made. While overall body weight remained stable during treatment, testicular weight in both animals was drastically decreased. A complete spermatogenic arrest in the testes was evident in house rats treated with 50 mg/day for 20 days and in the gerbil treated with 25 mg/day for 25 days. The seminiferous tubules showed marked degeneration, lined by 1 or 2 cell layers. Epididymides showed degenerative changes as well. RNA contents of the testes, epididydmides, and seminal vesicles of treated anials were significantly lowered as was sialilc acid content. Total cholesterol was increased significantly. M. conzattii causes an effective inhibition of spermatogenesis in gerbils and house rats in 25 states and induces infertility. PMID:598890

  20. Aminoglycoside ototoxicity and hair cell ablation in the adult gerbil: A simple model to study hair cell loss and regeneration

    PubMed Central

    Abbas, Leila; Rivolta, Marcelo N.

    2015-01-01

    The Mongolian gerbil, Meriones unguiculatus, has been widely employed as a model for studies of the inner ear. In spite of its established use for auditory research, no robust protocols to induce ototoxic hair cell damage have been developed for this species. In this paper, we demonstrate the development of an aminoglycoside-induced model of hair cell loss, using kanamycin potentiated by the loop diuretic furosemide. Interestingly, we show that the gerbil is relatively insensitive to gentamicin compared to kanamycin, and that bumetanide is ineffective in potentiating the ototoxicity of the drug. We also examine the pathology of the spiral ganglion after chronic, long-term hair cell damage. Remarkably, there is little or no neuronal loss following the ototoxic insult, even at 8 months post-damage. This is similar to the situation often seen in the human, where functioning neurons can persist even decades after hair cell loss, contrasting with the rapid, secondary degeneration found in rats, mice and other small mammals. We propose that the combination of these factors makes the gerbil a good model for ototoxic damage by induced hair cell loss. PMID:25783988

  1. Primary Genetic Investigation of a Hyperlipidemia Model: Molecular Characteristics and Variants of the Apolipoprotein E Gene in Mongolian Gerbil

    PubMed Central

    Liu, Yuehuan; Wu, Jiusheng; Shi, Qiaojuan; Guo, Honggang; Ying, Huazhong; Xu, Ningying

    2014-01-01

    The objective of this work was to establish a novel Mongolian gerbil (Meriones unguiculatus) hyperlipidemia model and to investigate its susceptibility genetic basis. Two rodent (gerbil and rat) hyperlipidemia models were induced by feeding a high fat/high-cholesterol (HF/HC) diet. There were significant increases of serum total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in gerbils within a 4-week modeling period. About 10–30% of >8-month-old individuals developed hyperlipidemia spontaneously. The apolipoprotein E (ApoE) gene was cloned by merging a sequence of rapid amplification of cDNA ends (RACE) and nested polymerase chain reaction products. The results revealed an open reading frame of 948 bp, encoding a protein of 298 amino acids. The gene without a 5′-UTR region in the first intron was highly homologous to human Apo-A-I and rat Apo-A-IV. The distribution of expression of the ApoE gene in liver, brain, heart, lung, kidney, and adrenal gland was detected by an ABC immunohistochemical procedure. Three single nucleotide polymorphisms (SNPs; C97T, G781T, and A1774T) were first found using PCR-single-strand conformation polymorphism (PCR-SSCP) in a closed population containing 444 animals. Correlation analysis confirmed that new SNPs , age, and gender were associated significantly (P < 0.05) with hyperlipidemia. PMID:25006576

  2. Aminoglycoside ototoxicity and hair cell ablation in the adult gerbil: A simple model to study hair cell loss and regeneration.

    PubMed

    Abbas, Leila; Rivolta, Marcelo N

    2015-07-01

    The Mongolian gerbil, Meriones unguiculatus, has been widely employed as a model for studies of the inner ear. In spite of its established use for auditory research, no robust protocols to induce ototoxic hair cell damage have been developed for this species. In this paper, we demonstrate the development of an aminoglycoside-induced model of hair cell loss, using kanamycin potentiated by the loop diuretic furosemide. Interestingly, we show that the gerbil is relatively insensitive to gentamicin compared to kanamycin, and that bumetanide is ineffective in potentiating the ototoxicity of the drug. We also examine the pathology of the spiral ganglion after chronic, long-term hair cell damage. Remarkably, there is little or no neuronal loss following the ototoxic insult, even at 8 months post-damage. This is similar to the situation often seen in the human, where functioning neurons can persist even decades after hair cell loss, contrasting with the rapid, secondary degeneration found in rats, mice and other small mammals. We propose that the combination of these factors makes the gerbil a good model for ototoxic damage by induced hair cell loss. PMID:25783988

  3. Tspy is nonfunctional in the Mongolian gerbil but functional in the Syrian hamster.

    PubMed

    Karwacki, Violetta; Kovac, Judit; Mauceri, Grazia; Backhaus, Arne; Föhse, Lisa; Schmidtke, Jörg; Schubert, Stephanie

    2006-07-01

    The TSPY gene is conserved in placental mammals and encodes the testis-specific protein, Y encoded. Within the testis, TSPY expression is restricted to germ cells, and it is assumed that TSPY plays a role in the proliferation of germ cells. Since it was first discovered in humans, TSPY orthologous gene families have been subsequently characterized in many mammalian lineages. In contrast to the situation in cattle and primates, in which TSPY is organized in a moderately repetitive cluster, including functional members and pseudogenes, a peculiar situation is observed in rodents, in which Tspy has been become low or single copy and degenerated to a pseudogene in some species of the subgenus Mus. We have extended this approach and investigated Tspy gene evolution in the Syrian hamster (Mesocricetus auratus) and the Mongolian gerbil (Meriones unguiculatus). Whereas the Syrian hamster Tspy is functionally conserved, organized in multiple copies, and expressed only in testis, the closely related Mongolian gerbil possesses a single-copy pseudogene that is unable to generate a functional transcript. Thus, the Tspy locus has degenerated at least twice at different points of rodent evolution, strongly supporting the hypothesis that the decay of Y-chromosomal genes is an intrinsic evolutionary process. TSPY is the first example of a Y-chromosomal tandem repetitive gene whose decay could be studied in two independent mammalian lineages. PMID:16626932

  4. Differential bioavailability, clearance, and tissue distribution of the acyclic tomato carotenoids lycopene and phytoene in mongolian gerbils.

    PubMed

    Moran, Nancy Engelmann; Clinton, Steven K; Erdman, John W

    2013-12-01

    Lycopene (LYC) is the major tomato carotenoid and is the focus of substantial research. Phytoene (PE), a minor tomato carotenoid, is found in human blood and tissues in similar concentrations to LYC. To determine which metabolic differences underlie this phenomenon, Mongolian gerbils (Meriones unguiculatus, n = 56) were fed control or tomato powder (TP)-containing diets (to establish steady-state serum and tissue carotenoid concentrations similar to tomato-fed humans) for 26 d. The TP-fed gerbils were then provided either a single, oral, cottonseed oil (CO) vehicle dose and tissues were collected at 6 h or they were provided unlabeled PE or LYC in CO and tissues were evaluated at 6, 12, or 24 h. In vehicle-dosed, TP-fed gerbils, LYC was the major carotenoid (≥ 55% carotenoids) in liver, spleen, testes, and the prostate-seminal vesicle complex, whereas PE was the major serum and adipose carotenoid (≥ 37% total carotenoid) and phytofluene was the major carotenoid (≥ 38%) in adrenals and lungs. PE dosing increased hepatic, splenic, and serum PE concentrations compared with vehicle dosing (P < 0.05) from 6 to 24 h, whereas LYC dosing increased only serum LYC at 6 and 12 h (P < 0.05) compared with vehicle dosing. This suggested PE was more bioavailable and cleared more slowly than LYC. To precisely track absorptive and distributive differences, (14)C-PE or (14)C-LYC (n = 2/group) was provided to TP-fed gerbils. Bioavailability assessed by carcass (14)C-content was 23% for PE and 8% for LYC. Nearly every extra-hepatic tissue accumulated greater dose radioactivity after (14)C-PE than (14)C-LYC dosing. Thus, LYC and PE, which structurally differ only by saturation, pharmacokinetically differ in bioavailability, tissue deposition, and clearance. PMID:24108134

  5. Differential Bioavailability, Clearance, and Tissue Distribution of the Acyclic Tomato Carotenoids Lycopene and Phytoene in Mongolian Gerbils123

    PubMed Central

    Moran, Nancy Engelmann; Clinton, Steven K.; Erdman, John W.

    2013-01-01

    Lycopene (LYC) is the major tomato carotenoid and is the focus of substantial research. Phytoene (PE), a minor tomato carotenoid, is found in human blood and tissues in similar concentrations to LYC. To determine which metabolic differences underlie this phenomenon, Mongolian gerbils (Meriones unguiculatus, n = 56) were fed control or tomato powder (TP)-containing diets (to establish steady-state serum and tissue carotenoid concentrations similar to tomato-fed humans) for 26 d. The TP-fed gerbils were then provided either a single, oral, cottonseed oil (CO) vehicle dose and tissues were collected at 6 h or they were provided unlabeled PE or LYC in CO and tissues were evaluated at 6, 12, or 24 h. In vehicle-dosed, TP-fed gerbils, LYC was the major carotenoid (≥55% carotenoids) in liver, spleen, testes, and the prostate-seminal vesicle complex, whereas PE was the major serum and adipose carotenoid (≥37% total carotenoid) and phytofluene was the major carotenoid (≥38%) in adrenals and lungs. PE dosing increased hepatic, splenic, and serum PE concentrations compared with vehicle dosing (P < 0.05) from 6 to 24 h, whereas LYC dosing increased only serum LYC at 6 and 12 h (P < 0.05) compared with vehicle dosing. This suggested PE was more bioavailable and cleared more slowly than LYC. To precisely track absorptive and distributive differences, 14C-PE or 14C-LYC (n = 2/group) was provided to TP-fed gerbils. Bioavailability assessed by carcass 14C-content was 23% for PE and 8% for LYC. Nearly every extra-hepatic tissue accumulated greater dose radioactivity after 14C-PE than 14C-LYC dosing. Thus, LYC and PE, which structurally differ only by saturation, pharmacokinetically differ in bioavailability, tissue deposition, and clearance. PMID:24108134

  6. Measurement of hepatic sterol synthesis in the Mongolian gerbil in vivo using (/sup 3/H)water: diurnal variation and effect of type of dietary fat

    SciTech Connect

    Mercer, N.J.; Holub, B.J.

    1981-01-01

    The hepatic synthesis of sterol was measured in the male Mongolian gerbil (Meriones unguiculatus) in vivo following the administration of (/sup 3/H)water by monitoring the incorporation of radioactivity into digitonin-precipitable sterol. A diurnal rhythm in cholesterol synthesis was exhibited under conditions of ad libitum feeding with alternating 12-hour periods of light (0200 to 1400 hr) and dark (1400 to 0200 hr). The zenith was reached between 1500 and 2100 hr and the nadir approximately 10-12 hours later between 0200 and 0400 hr, which provided a zenith/nadir ratio of 9.6 to 1.0. The in vivo rates of hepatic sterol synthesis and plasma cholesterol levels were measured in gerbils fed semi-purified diets containing either 19.5% beef tallow + 0.5% safflower, 20% lard, or 20% safflower oil and widely differing ratios of polyunsaturated: saturated fatty acids. All diets were equalized to contain 0.01% cholesterol and 0.05% plant sterol. After 3 days on the experimental diets, the mean rates of cholesterol synthesis (nmol/g liver per hr) were 41.5, 26.6, and 13.8 for animals fed the diets containing beef tallow, lard, and safflower oil, respectively. After 7 and 14 days, synthetic rates were lowest in the gerbils fed safflower oil as were also the plasma cholesterol levels. These results indicate that the type of dietary lipid can significantly influence the in vivo rate of sterol biosynthesis in gerbil liver. This response may contribute, at least in part, to the observed differences in plasma cholesterol levels.

  7. Influence of dietary cholesterol on the relative synthesis of hepatic glycerides and molecular classes of 1,2-diglycerides and phospholipids in the gerbil in vivo

    SciTech Connect

    Andersen, D.B.; Holub, B.J.

    1985-03-01

    The influence of dietary cholesterol on the relative rates of synthesis of hepatic lipids in the male Mongolian gerbil, Meriones unguiculatus, was studied. The semi-purified starch-based diet used lard as the dietary fat and was fed with or without a 0.5% (by wt.) cholesterol supplement. Each animal received 300 microCi (2-/sup 3/H)-glycerol i.p. after 3 or 7 days on the dietary regimens. Relative rates of (2-/sup 3/H)-glycerol incorporation into the major hepatic glycerides in vivo was not affected significantly by dietary cholesterol (0.5% level), suggesting that alteration in the relative biosynthesis of these lipids could not readily account for the higher triglyceride (TG) to phospholipid (PL) mass ratio in liver with cholesterol feeding. However, there was evidence for an increased formation of 1,2-diglyceride (1,2-DG). The complement of molecular species of hepatic 1,2-DG, phosphatidylcholine (PC), and phosphatidylethanolamine (PE) formed de novo, as measured using isotopic glycerol, was not influenced greatly by dietary cholesterol, although lower mean rates of synthesis of tetraenoic relative to dienoic species of phospholipids were indicated in cholesterol-fed gerbils.

  8. Beta-endorphin-like and adrenocorticotropin-like materials in heart tissues of the rat, gerbil, hamster and guinea pig.

    PubMed

    Ng, T B; Ng, S L

    1990-01-01

    1. Heart tissues of several rodent species including the rat, gerbil (Meriones unguiculatus), hamster (Mesocricetus auratus) and guinea pig (Cavia porcellus) were extracted with an acetone-water-HCl mixture. An acid acetone powder was obtained by adding a copious volume of acetone to the extract. 2. Rat heart acid acetone powder was subjected to ion exchange chromatography on CM-cellulose. Gerbil heart acid acetone powder was subjected to salt fractionation, gel filtration on Sephadex G-10 and then ion exchange chromatography on CM-cellulose. Hamster and guinea pig heart acid acetone powders were subjected to gel filtration on Sephadex G-25. 3. The fractions were assayed for the ability to stimulate corticosterone production in isolated rat adrenal decapsular (zona fasciculata, zona reticularis and medulla) cells, to displace D-ala2-D-leu5-(tyrosyl-3,5-3H) enkephalin from binding to rat brain membranes, and to inhibit 125I-human beta-endorphin from binding to its antibodies. 4. The widespread occurrence of beta-endorphin-like immunoreactivity among the rat heart CM-cellulose fractions may reflect different species of beta-endorphin. The fraction with the highest beta-endorphin-like immunoreactivity and opiate receptor binding activity was strongly adsorbed on CM-cellulose. 5. In hamster and guinea pig hearts, beta-endorphin-like immunoreactivity and opiate receptor binding activity were distributed among high molecular weight and low molecular weight fractions. 6. In gerbil hearts, opiate receptor binding activity was present in fractions unretarded on Sephadex G-10 (i.e. with a molecular weight greater than 700) as well as in the retarded fractions (i.e. with a molecular weight smaller than 700).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1971555

  9. The complete mitochondrial genome of Meriones meridianus (Rodentia: Cricetidae) and its phylogenetic analysis.

    PubMed

    Luo, Guangjie; Liao, Jicheng

    2016-07-01

    Meriones meridianus belongs to the genus Meriones in Gerbillinae. Total length of complete mitochondrial genome of M. meridianus is 16,376 bp and the heavy strand contains 32.8% A, 13.1% G, 25.3% C and 28.8% T. Sequences of protein-coding genes are 11,341 bp in length, accounting for 69.25%, approximately. Results of phylogenetic analysis shown that M. meridianus and Meriones unguiculatus were clustered in a single branch. This conclusion would be an important data for relevant studies about the genus Meriones, and mitochondrial genome would be an important supplement for the gene pool of Rodentia. It would play a pivotal role in researches about phylogeography and proteomics involving M. meridianus as well. PMID:26075483

  10. The complete mitochondrial genome of Meriones libycus (Rodentia: Cricetidae) and its phylogenetic analysis.

    PubMed

    Luo, Guangjie; Liao, Jicheng

    2016-07-01

    Meriones libycus belongs to the genus Meriones in Gerbillinae, its complete mitochondrial genome is 16,341 bp in length. The heavy strand contains 32.8% A, 13.1% G, 25.3% C, 28.8% T, protein-coding genes approximately accounting for 69.54%. Results of phylogenetic analysis showed that M. libycus and Meriones unguiculatus were clustered together, and it was consistent with that of primary morphological taxonomy. This study verifies the evolutionary status of M. libycus in Meriones at the molecular level. The mitochondrial genome would be a significant supplement for the gene pool of Rodentia and the conclusion of phylogenetic analysis could be an important molecular evidence for the classification of Gerbillinae. PMID:26017047

  11. Bioavailability of beta-carotene (betaC) from purple carrots is the same as typical orange carrots while high-betaC carrots increase betaC stores in Mongolian gerbils (Meriones unguiculatus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vitamin A (VA) deficiency is a worldwide public health problem. Biofortifying existing sources of beta-carotene (betaC) and increasing dietary betaC could help combat the issue. Two studies were performed to investigate the relative betaC bioavailability of a betaC supplement to purple, high-betaC o...

  12. The Expression of the Androgen Receptor and Estrogen Receptor 1 is Related to Sex Dimorphism in the Gerbil Prostate Development.

    PubMed

    Sanches, Bruno D A; Maldarine, Juliana S; Zani, Bruno C; Biancardi, Manoel F; Santos, Fernanda C A; Góes, Rejane M; Vilamaior, Patricia S L; Taboga, Sebastião R

    2016-08-01

    The development of the prostate gland in females has not yet been clearly elucidated, and the sexual dimorphism associated with such gland development in general is far from being understood. In the present study, we used tridimensional (3D) reconstructions and histochemical and immunohistochemical techniques to describe the sexual dimorphism and its causes in the early postnatal development of the prostate in male and female Mongolian gerbils (Meriones unguiculatus). We observed that the female prostate was smaller, had fewer branches throughout the development, and underwent differentiation earlier than that in males. Also, the expression of the estrogen receptor 1 (ESR1 or ER-alpha) and fibroblast growth factor 10 (FGF10) was decreased in the periductal region, and the expression of the androgen receptor (AR) was increased in the epithelium. All together, these changes decreased proliferation and branching and led to an earlier prematuration of the female prostate. These new data shed light on the underlying mechanisms involved with the sexual dimorphism in the development of the prostate. Anat Rec, 299:1130-1139, 2016. © 2016 Wiley Periodicals, Inc. PMID:27184581

  13. Aging effects on the binaural interaction component of the auditory brainstem response in the Mongolian gerbil: Effects of interaural time and level differences.

    PubMed

    Laumen, Geneviève; Tollin, Daniel J; Beutelmann, Rainer; Klump, Georg M

    2016-07-01

    The effect of interaural time difference (ITD) and interaural level difference (ILD) on wave 4 of the binaural and summed monaural auditory brainstem responses (ABRs) as well as on the DN1 component of the binaural interaction component (BIC) of the ABR in young and old Mongolian gerbils (Meriones unguiculatus) was investigated. Measurements were made at a fixed sound pressure level (SPL) and a fixed level above visually detected ABR threshold to compensate for individual hearing threshold differences. In both stimulation modes (fixed SPL and fixed level above visually detected ABR threshold) an effect of ITD on the latency and the amplitude of wave 4 as well as of the BIC was observed. With increasing absolute ITD values BIC latencies were increased and amplitudes were decreased. ILD had a much smaller effect on these measures. Old animals showed a reduced amplitude of the DN1 component. This difference was due to a smaller wave 4 in the summed monaural ABRs of old animals compared to young animals whereas wave 4 in the binaural-evoked ABR showed no age-related difference. In old animals the small amplitude of the DN1 component was correlated with small binaural-evoked wave 1 and wave 3 amplitudes. This suggests that the reduced peripheral input affects central binaural processing which is reflected in the BIC. PMID:27173973

  14. Identification, cloning and regulation of cDNA encoding aldo-keto reductase 1B7 in the adrenal gland of two Saharan rodents Meriones libycus (Libyan jird) and Gerbillus gerbillus (gerbil).

    PubMed

    Mataoui-Mazari, Houria; Amirat, Zaïna; Khammar, Farida; Martinez, Antoine

    2011-12-01

    Aldo-Keto Reductase 1B7 (AKR1B7) is a mouse aldose reductase-like protein with two major sites of expression, the vas deferens and the adrenal cortex. In the adrenal cortex, Akr1b7 is an adrenocorticotropin (ACTH)-responsive-gene whose product scavenges harmful byproducts of steroidogenesis and limits stress response through the biosynthesis of prostaglandin F2α. The purpose of the present study was to explore the possible expression of AKR1B7 in the adrenal glands of two saharan rodents, Libyan jird and Lesser Egyptian gerbil. Western blot analyses demonstrated that a protein related to murine/rat AKR1B7 was highly expressed in adrenals and absent from vas deferens of both saharan species. Based on conserved sequences between mouse and rat, full length cDNA were cloned and sequenced in both species while hormonal regulation and tissue localization were explored in Libyan jird. Both cDNA encoded the expected 316 amino acids protein typical of AKR1B subfamily and contained the highly conserved catalytic tetrad consisting in Asp-44, Tyr-49, Lys-78 and His-111 residues. The deduced proteins shared higher identities with aldose reductase-like, i.e. AKR1B7 (86-94%), AKR1B8 and AKR1B10 (83-86%) than with aldose reductase group, i.e. AKR1B1 and AKR1B3 (70%). Phylogenetic analysis showed that the Libyan jird and gerbil enzymes were more closely related to murine and rat AKR1B7 than to the other AKR1B members. Northern blot analyses of total RNA from Libyan jird adrenals showed a single mRNA transcript of 1.4 kb whose expression was dependent on circulating ACTH levels. In conclusion, we demonstrate here that adrenal glands of Libyan jird and gerbil express both an ortholog of the murine/rat Akr1b7 gene and that ACTH-responsiveness is at least conserved in Libyan jird. PMID:21963864

  15. Prenatal exposure to ethinylestradiol alters the morphologic patterns and increases the predisposition for prostatic lesions in male and female gerbils during ageing.

    PubMed

    Perez, Ana P S; Biancardi, Manoel F; Caires, Cássia R S; Falleiros-Junior, Luiz R; Góes, Rejane M; Vilamaior, Patricia S L; Santos, Fernanda C A; Taboga, Sebastião R

    2016-02-01

    Ethinylestradiol (EE) is an endocrine disruptor (ED) which acts as an oestrogen agonist; this compound is known as an oral contraceptive. Male and female rodents exposed to EE during critical time points of development, such as in the prenatal period, show alterations in their reproductive tract during adulthood. Few studies have placed an emphasis on the effects of EE during ageing. Thus, this study had as it's objective the analysis of the morphological and immunohistochemical effects of exposure to EE in the prenatal period on ventral male prostate and female prostate of gerbils (Meriones unguiculatus) during ageing. The animals were exposed to EE (15 μg/kg/day) during the 18-22th days of prenatal life (EE/PRE group), and the analyses were performed when the male and female reached 12 months of age. Our results showed an increase in the development of prostatic intraepithelial neoplasia (PIN), which was observed in the male and female prostate of EE/PRE groups. Immunohistochemistry showed a rise in prostatic epithelial and basal cells immunoreactivity, respectively, and to AR and p63 in the male EE/PRE. There were alterations in the morphological pattern of the prostatic glands and increase in predisposition to emergence of prostatic lesions of both sexes during ageing. Despite male and female having been exposed to the same doses of EE, the "exposure to EE promoted modifications" more accentuated in the male prostate. Thus the male gland is more sensitive to the action of this synthetic oestrogen than the female prostate. PMID:26852889

  16. Desert gerbils affect bacterial composition of soil.

    PubMed

    Kuznetsova, Tatyana A; Kam, Michael; Khokhlova, Irina S; Kostina, Natalia V; Dobrovolskaya, Tatiana G; Umarov, Marat M; Degen, A Allan; Shenbrot, Georgy I; Krasnov, Boris R

    2013-11-01

    Rodents affect soil microbial communities by burrow architecture, diet composition, and foraging behavior. We examined the effect of desert rodents on nitrogen-fixing bacteria (NFB) communities by identifying bacteria colony-forming units (CFU) and measuring nitrogen fixation rates (ARA), denitrification (DA), and CO2 emission in soil from burrows of three gerbil species differing in diets. Psammomys obesus is folivorous, Meriones crassus is omnivorous, consuming green vegetation and seeds, and Dipodillus dasyurus is predominantly granivorous. We also identified NFB in the digestive tract of each rodent species and in Atriplex halimus and Anabasis articulata, dominant plants at the study site. ARA rates of soil from burrows of the rodent species were similar, and substantially lower than control soil, but rates of DA and CO2 emission differed significantly among burrows. Highest rates of DA and CO2 emission were measured in D. dasyurus burrows and lowest in P. obesus. CFU differed among bacteria isolates, which reflected dietary selection. Strains of cellulolytic representatives of the family Myxococcaceae and the genus Cytophaga dominated burrows of P. obesus, while enteric Bacteroides dominated burrows of D. dasyurus. Burrows of M. crassus contained both cellulolytic and enteric bacteria. Using discriminant function analysis, differences were revealed among burrow soils of all rodent species and control soil, and the two axes accounted for 91 % of the variance in bacterial occurrences. Differences in digestive tract bacterial occurrences were found among these rodent species. Bacterial colonies in P. obesus and M. crassus burrows were related to bacteria of A. articulata, the main plant consumed by both species. In contrast, bacteria colonies in the burrow soil of D. dasyurus were related to bacteria in its digestive tract. We concluded that gerbils play an important role as ecosystem engineers within their burrow environment and affect the microbial complex of

  17. The Gerbils Are Here

    ERIC Educational Resources Information Center

    Murphy, James E.

    1973-01-01

    Describes the natural habitat, life-history, and behavior of gerbils. These animals do not drink water, are virtually odorless, can withstand wide temperature ranges, and require minimal attention. As a result they have become popular in research and science classrooms in recent years. (JR)

  18. Immunizing potential of ultraviolet-attenuated cercariae of Schistosoma mansoni in rodent hosts.

    PubMed

    Kamiya, H; Ozaki, T; Nakayama, H; Inaba, T

    1993-01-01

    Schistosoma mansoni cercariae attenuated with ultraviolet (UV) irradiation (254 nm) at a dose of 18 mJ/cm2 induced partial resistance against a homologous challenge in male ICR mice and male Hartley guinea pigs. The reduction in the adult worm burden was 51% and 37% +/- 13%, respectively. On the other hand, male and female Mongolian gerbils (Meriones unguiculatus) vaccinated with UV-attenuated cercariae exhibited marginal resistance (13% +/- 9% and 22% +/- 10%, respectively). This raises the possibility that gerbils might have an unknown immune-characteristic nature. The usefulness of UV-attenuated cercariae is discussed with respect to the control of the disease. PMID:8327451

  19. Development of Cochlear Mechanics in the Gerbil

    NASA Astrophysics Data System (ADS)

    Overstreet, E. H., III; Temchin, A. N.; Ruggero, M. A.

    2003-02-01

    Using a laser velocimeter, basilar-membrane vibrations were measured in adult and neonatal gerbils at a site with characteristic frequency of 34-37 kHz located 1.2 mm from the round window of the cochlea. Stapes vibrations and compound action potential thresholds were also measured up to frequencies exceeding the site's characteristic frequency. In adult gerbils, basilar-membrane responses at this site exhibited a compressive nonlinearity. Post-mortem, basilar-membrane responses in adults became "passive", i.e., linear and insensitive, and the best frequency shifted downward by about 0.5 octave. At 14 and 16 days after birth, basilar-membrane responses in neonatal gerbils were passive but otherwise very different from post-mortem responses in adult gerbils: best frequency was more than an octave lower, the steep slopes of the phase-vs.-frequency curves were shifted downward in frequency by nearly one octave, and the maximum phase lags amounted to only 180 degrees re. stapes. Best frequencies and phase lags increased systematically between 14 and 20 days after birth, implying drastic alterations of the passive material properties of cochlear tissues and accounting for a large part of the shift in best frequency that characterizes maturation of auditory-nerve responses during the same period.

  20. Noradrenergic involvement in pinealectomy induced convulsions in gerbils.

    PubMed

    Champney, T H

    1990-12-11

    Gerbils treated with various noradrenergic compounds were pinealectomized (PINX) or sham-operated (SHAM) and observed for convulsive activity. Although declines in cortical and hypothalamic norepinephrine content were found after alpha-methylparatyrosine (alpha MPT) or PINX, treatment with alpha MPT did not produce convulsions in SHAM gerbils or in gerbils which were PINX one week earlier. Likewise, alpha MPT did not increase the number or severity of convulsions observed in acutely PINX gerbils. Treatment with propranolol or isoproterenol did not have any effect on convulsive activity of PINX gerbils, except that isoproterenol increased the excitability of all the gerbils. In conclusion, reducing catecholamine content or modifying beta-noradrenergic receptor activity was not able to alter the convulsive activity which occurs after acute PINX. PMID:2293111

  1. Housing and husbandry conditions affect stereotypic behaviour in laboratory gerbils.

    PubMed

    Waiblinger, Eva; König, Barbara

    2007-01-01

    An artificial burrow was developed which fits into standard laboratory cages and significantly reduces stereotypic digging in gerbils. Also, the causes of bar-chewing were assessed experimentally. Neither the lack of gnawing material, nor the spatial proximity of cage-lid bars and food in the hopper nor the routine husbandry procedure of transferring juvenile gerbils to a fresh cage, but premature separation of juvenile gerbils from their parents before the birth of younger siblings significantly increased bar-chewing. PMID:19835062

  2. Diffuse retinochoroiditis due to Baylisascaris procyonis in Monglian gerbils.

    PubMed

    Akao, N; Hayashi, E; Sato, H; Fujita, K; Furuoka, H

    2003-02-01

    Baylisascaris procyonis, raccoon roundworm, causes a severe retinal lesion in humans. The lesion is termed as diffuse unilateral subacute neuroretinitis (DUSN). To understand the pathogenesis of B. procyonis in gerbils, we inoculated 17 embryonated eggs/g body weight of B. procyonis into 15 male Mongolian gerbils, Merionis ungiculatus, and monitored their fundi with an ophthalmoscope. Six of 15 gerbils (40%) showed severe retinitis with a sinuous track due to larval movement. The lesions extended across nearly half of the affected fundi. Histopathological examination revealed perivasculitis in the optic disk region, inflammatory proliferation of the pigment cells, and vitreitis in most cases. These findings were similar to those in human cases of DUSN, suggesting that gerbils might be a useful model for understanding the pathogenesis of B. procyonis infection in humans. PMID:12659323

  3. The Gerbil Jar: A Basic Home Experience in Operant Conditioning.

    ERIC Educational Resources Information Center

    Plant, L.

    1980-01-01

    Explains how a teaching method such as allowing students to raise gerbils at home can encourage students to gain experience with the fundamental techniques of operant conditioning which are otherwise generally unavailable to students in large introductory psychology courses. (DB)

  4. Evaluation of plant extracts for sweetness using the Mongolian gerbil.

    PubMed

    Jakinovich, W; Moon, C; Choi, Y H; Kinghorn, A D

    1990-01-01

    Extracts of Thladiantha grosvenorii fruits, Stevia rebaudiana leaves, and Abrus precatorius leaves were investigated using Mongolian gerbil electrophysiological and conditioned taste aversion procedures, which were designed to respond to sucrose. A close correlation was observed between extracts of these sweet plants known to contain sweet principles and those extracts indicated as being sweet by a combination of these gerbil bioassays. The methods employed seem to be suitable for use in aiding the purification of highly sweet compounds of plant origin. PMID:2348201

  5. Establishment and Characterization of a Newly Established Diabetic Gerbil Line

    PubMed Central

    Li, Xiaohong; Lu, Jing; Wang, Ying; Huo, Xueyun; Li, Zhenkun; Zhang, Shuangyue; Li, Changlong; Guo, Meng; Du, Xiaoyan; Chen, Zhenwen

    2016-01-01

    Objectives We aimed to selectively breed a spontaneous diabetic gerbil when a sub-line of inbred gerbil showed increased blood glucose levels was found recently. Then we investigated the characteristics including the serum insulin, triglyceride, cholesterol, leptin, adiponectin and explored the underlying molecular mechanism for the diabetic phenotype. Methods The spontaneous diabetic line of gerbils was selectively inbreed the sub-line of gerbil by monitoring blood glucose of each animal. The serum insulin, adiponectin, and leptin levels were tested using an ELISA kit. The expression levels of GLUT4, Akt, leptin, adiponectin, and calpain 10 (CAPN10) were tested by western blot and Quantitative Real-time PCR (qPCR) in liver, skeletal muscle, and white adipose. Results Our results show that the percentages of animals with FPG≥5.2 (mmol/l), PG2h≥6.8 (mmol/l) and both FPG≥5.2 and PG2h≥6.8 (mmol/l) were increased with the number of breeding generations from F0 (21.33%) to F6 (38.46%). These diabetic gerbils exhibited insulin resistance and leptin resistance as well as decreased adiponectin level in the serum. We also observed decreased expression of adiponectin and increased expression of leptin in the skeletal muscle, respectively. Conclusions These results indicate that we have primarily established a spontaneous diabetic gerbil line, and the diabetic phenotypes may have been accounted for by altered expression of leptin and adiponectin. PMID:27427908

  6. The distribution of mucous secreting cells in the gastrointestinal tracts of three small rodents from Saudi Arabia: Acomys dimidiatus, Meriones rex and Meriones libycus.

    PubMed

    Johnson, Olga; Marais, Sumine; Walters, Jacklynn; van der Merwe, Elizabeth L; Alagaili, Abdulaziz N; Mohammed, Osama B; Bennett, Nigel C; Kotzé, Sanet H

    2016-03-01

    The proportion of mucin phenotypes (which form the protective biofilm of the gastrointestinal tract) differs between intestinal regions. This study examines the distribution of mucin secreting cells in the gastrointestinal tracts of the Eastern spiny mouse (Acomys dimidiatus), King jird (Meriones rex) and Libyan jird (Meriones libycus), which inhabit the dry and hot deserts of Saudi Arabia. Intestinal tract samples were processed to wax and tissue sections stained with Alcian Blue-Periodic Acid Schiff (AB-PAS) and High Iron Diamine-Alcian Blue (HID-AB) in order to determine different mucin phenotypes by quantitative analysis. Mixed mucin secreting cells (combined neutral and acid) was the predominant mucin secreting cell type observed throughout the gastrointestinal tract in all species. Acid mucin secreting goblet cells were mainly located in the colon. A. dimidiatus presented with significantly more total sialo than sulfomucin secreting cells while the opposite was true for both Meriones species. The distribution of mucin secreting cells is therefore similar to previously reported results for small mammals not living under arid conditions. PMID:26743350

  7. [The tropical rat mite Ornithonyssus bacoti attacks humans in Iceland.].

    PubMed

    Skírnisson, K

    2001-12-01

    In the summer of 2001 the obligate, intermittent tropical rat mite Ornithonyssus bacoti attacked humans in an Icelandic household where infected Mongolian gerbils (Meriones unguiculatus), bought in a local pet shop, had been kept for few months. After a rapid proliferation the mite started attacking the humans living in the house. A boy sharing room with the pets suffered from extensive dermatitis. Optimal conditions for O. bacoti are at 24-26 degrees C and a relative humidity of 47%. Similar conditions frequently occur indoors in Icelandic premises. Therefore, if O. bacoti has been noticed indoors, necessary measures should be undertaken to immediately eliminate the pest. PMID:17019023

  8. [Genetic characterization of the Geran virus (GERV, Bunyaviridae, Nairovirus, Qalyub group) isolated from the ticks Ornithodoros verrucosus Olenev, Zasukhin and Fenyuk, 1934 (Argasidae) collected in the burrow of Meriones erythrourus Grey, 1842 in Azerbaijan].

    PubMed

    L'vov, D K; Al'khovskiĭ, S V; Shchelkanov, M Iu; Deriabin, P G; Shchetinin, A M; Samokhvalov, E I; Aristova, V A; Gitel'man, A K; Botikov, A G

    2014-01-01

    The full-length genome of the unclassified Geran virus (GERV, strain LEIV-10899Az) isolated from the ticks (Ornithodoros verrucosus Olenev, Zasukhin and Fenyuk, 1934 (Argasidae, Ornithodorinae)) collected in the burrow of the red-tailed gerbils (Meriones (Cricedidae) erythrourus Grey, 1842) near the Geran station (Azerbaijan) was sequenced using the next-generation approach (GenBank ID: KF801649). It was shown that the GERV is a new representative of the Nairovirus genus (family Bunyaviridae). The comparative analysis of the full-length genome sequences of the GERV with other nairoviruses showed that the highest level of homology (55.6% for N protein (S-segment) of 54.2% for the polyprotein Gn/Gc (M-segment) and 74.8% for the RNA-dependent RNA polymerase (L-segment)) GERV had with the Chim virus (CHIMV) that is also associated with the shelters biocenoses (rodent burrows) in Central Asia and was previously assigned to the Qalyub virus group (QYBV). Comparing the GERV with the QYBV sequences (partial sequence 413 n.o. of RdRp gene) revealed a high level of homology: 74.3 and 97.4% for the nucleotide and amino acid sequences, respectively. The data obtained in this work provided an opportunity to classify the GERV to the QYBV group; the Nairovirus genus, to the family Bunyaviridae. PMID:25895205

  9. The Mongolian gerbil as a model for inflammatory bowel disease.

    PubMed

    Bleich, Eva-Maria; Martin, Myriam; Bleich, André; Klos, Andreas

    2010-06-01

    Mongolian gerbils are used as biomedical research models for a variety of diseases and are in some cases suited better than other rodents for basic research and therapeutic studies. The aim of this study was to establish and characterize a dextran sulphate sodium (DSS)-induced model in gerbils for the human inflammatory bowel disease (IBD) and to utilize them for a therapeutic study in vivo. Four concentrations (0.5%, 1%, 2% and 4%) of DSS were administered via drinking water for 7 days; based on these results, a concentration of 3% DSS was given for 9 days in a second approach. Fluid uptake and general clinical condition were assessed daily using a clinical score. Caecum and colon were scored histologically. Fluid uptake was affected by addition of DSS to the drinking water. First clinical symptoms were observed at day 4 of DSS treatment with a considerable increase in clinical score parameters only in gerbils receiving 2% or 4% DSS. Histologically, ulceration and inflammation were observed predominantly in the caecum of gerbils treated with at least 1% DSS; reproducible inflammation in the colon required at least 2% DSS. Using 3% DSS for 9 days, considerably more inflammation was induced in the colon, comparable with lesions usually observed in the mouse model. Using an optimized protocol, DSS treatment induces reproducibly typhlocolitis in Mongolian gerbils, rendering them as a useful model for IBD. PMID:20113376

  10. Phylogenetic status of Pneumocystis from corticosteroid-treated gerbils.

    PubMed

    Feng, XianMin; Wei, ChaoJun; Adam, Rodney D; Li, ZiHui; Lu, Siqi

    2010-10-01

    Pneumocystis spp. infect the lungs of multiple mammalian species and cause disease in immunosuppressed individuals. The Pneumocystis isolates that have been studied to date fall into two major clades, those from primates and those from rodents. Within each of these clades, different species have been described on the basis of host specificity and differences in sequence and morphology. Here, we demonstrate that dexamethasone immunosuppression consistently results in histologically apparent lung infection in gerbils (28/35 animals). Sequence analysis of the 18S, 5.8S and internal transcribed spacer regions of the rDNA and a portion of the mitochondrial large subunit rDNA demonstrated that this gerbil Pneumocystis is grouped with other rodent Pneumocystis spp., but is distinct from them. Our results suggest that gerbil Pneumocystis differs sufficiently from Pneumocystis species found in other rodents to be considered a separate species. PMID:20953947

  11. Basilar membrane vibration in the gerbil hemicochlea.

    PubMed

    Richter, C P; Evans, B N; Edge, R; Dallos, P

    1998-05-01

    Excised gerbil cochleae were cut along the mid-modiolar plane (hemicochlea). Along one-half turn of this preparation, fluorescent microbeads were placed on the basilar membrane (BM). The BM was vibrated with click stimuli (50 micros) produced mechanically by a piezo pusher. The stimulus delivery probe could be positioned either more apical or more basal from the beads. Vibration patterns were measured with a wide bandwidth photomultiplier from the movements of the beads. When the probe was positioned more basal, the responses to click stimuli were brief, damped sinusoids. According to the fast Fourier transforms (FFTs) of the averaged time wave forms, the best frequency between successive beads decreased toward the apex (0.8 octave/mm). Sharpness of tuning of the normalized FFT spectra (NQ10dB) on average was 1.5. Response amplitude at a fixed input level, measured at different beads away from the stimulation site, dropped exponentially (58 dB/mm). In addition, for each individual bead, amplitude dropped linearly with decreasing stimulus intensity. In experiments where the stimulating probe was placed more apical, two major properties were observed: first, beads revealed only the spectral components present in the motion of the probe. Second, magnitude reduction of the displacement of the cochlear partition was greater, on average 155 dB/mm, indicating a lack of significant propagation in the reverse direction. PMID:9582202

  12. Ontogeny of the sexually dimorphic area of the gerbil hypothalamus.

    PubMed

    Ulibarri, C M; Yahr, P

    1993-07-16

    The sexually dimorphic area (SDA) of the gerbil hypothalamus is a set of cell groups in the medial preoptic area that is essential for masculine sexual behavior and implicated in the hormonal control of scent making and ultrasound production. The adult SDA shrinks after gonadectomy unless the gerbils receive testosterone. So does the SDA pars compacta, a small cell group in the SDA of males that is seldom seen in females. Here, development of the SDA and SDApc, and of a second, small, compact cell group, the cmSDApc, that lies caudal and medial to the SDApc, is described. Development of the SDApc and cmSDApc was studied quantitatively by assessing their incidence and volume in both sexes from birth (PND 1) to adulthood (PND 150). The volume of the entire SDA was studied from PND 45 to 150. In male gerbils, puberty begins around PND 40 and is complete by PND 90-120. The male SDA enlarged relative to the cross-sectional area of the hypothalamus as puberty began, but the female SDA did not. The SDApc was present in virtually all gerbils at birth and was the same size in both sexes. Over the next two weeks, the SDApcs of females disappeared while those of males persisted and doubled in size. Like the SDApc, the cmSDApc was larger and more common in males than in females, but it became smaller and less prevalent in both sexes during the first two weeks after birth. PMID:8403369

  13. Role of Energy Sensor TlpD of Helicobacter pylori in Gerbil Colonization and Genome Analyses after Adaptation in the Gerbil

    PubMed Central

    Behrens, Wiebke; Schweinitzer, Tobias; Bal, Joena; Dorsch, Martina; Bleich, André; Kops, Friederike; Brenneke, Birgit; Didelot, Xavier; Suerbaum, Sebastian

    2013-01-01

    Helicobacter pylori maintains colonization in its human host using a limited set of taxis sensors. TlpD is a proposed energy taxis sensor of H. pylori and dominant under environmental conditions of low bacterial energy yield. We studied the impact of H. pylori TlpD on colonization in vivo using a gerbil infection model which closely mimics the gastric physiology of humans. A gerbil-adapted H. pylori strain, HP87 P7, showed energy-dependent behavior, while its isogenic tlpD mutant lost it. A TlpD-complemented strain regained the wild-type phenotype. Infection of gerbils with the complemented strain demonstrated that TlpD is important for persistent infection in the antrum and corpus and suggested a role of TlpD in horizontal navigation and persistent corpus colonization. As a part of the full characterization of the model and to gain insight into the genetic basis of H. pylori adaptation to the gerbil, we determined the complete genome sequences of the gerbil-adapted strain HP87 P7, two HP87 P7 tlpD mutants before and after gerbil passage, and the original human isolate, HP87. The integrity of the genome, including that of a functional cag pathogenicity island, was maintained after gerbil adaptation. Genetic and phenotypic differences between the strains were observed. Major differences between the gerbil-adapted strain and the human isolate emerged, including evidence of recent recombination. Passage of the tlpD mutant through the gerbil selected for gain-of-function variation in a fucosyltransferase gene, futC (HP0093). In conclusion, a gerbil-adapted H. pylori strain with a stable genome has helped to establish that TlpD has important functions for persistent colonization in the stomach. PMID:23836820

  14. [Metabolic adaptations of the gerbil, Gerbillus campestris, to a desert climate. Comparison with white mice].

    PubMed

    Oufara, S

    1987-01-01

    Metabolic rate of gerbils was lower than that of mice (35%). We tried to assess the part played by brown adipose tissue in this low level. Mitochondrial respiration (state 4), protein content and cytochrome-oxidase activity of interscapular BAT mitochondria were very low in gerbils compared to mice, whereas in liver and muscle these parameters were not significantly different. Like in fasting animals, the low level of basal energy expenditure of gerbils may be ascribed to low activity of BAT. PMID:2842012

  15. Synaptic remodeling in the dentate gyrus, CA3, CA1, subiculum, and entorhinal cortex of mice: effects of deprived rearing and voluntary running.

    PubMed

    Schaefers, Andrea T U; Grafen, Keren; Teuchert-Noodt, Gertraud; Winter, York

    2010-01-01

    Hippocampal cell proliferation is strongly increased and synaptic turnover decreased after rearing under social and physical deprivation in gerbils (Meriones unguiculatus). We examined if a similar epigenetic effect of rearing environment on adult neuroplastic responses can be found in mice (Mus musculus). We examined synaptic turnover rates in the dentate gyrus, CA3, CA1, subiculum, and entorhinal cortex. No direct effects of deprived rearing on rates of synaptic turnover were found in any of the studied regions. However, adult wheel running had the effect of leveling layer-specific differences in synaptic remodeling in the dentate gyrus, CA3, and CA1, but not in the entorhinal cortex and subiculum of animals of both rearing treatments. Epigenetic effects during juvenile development affected adult neural plasticity in mice, but seemed to be less pronounced than in gerbils. PMID:20508828

  16. Ultrastructure, ZIO-staining and chromaffinity of gerbil pinealocytes.

    PubMed

    Chau, Y P; Liao, K K; Kao, M H; Huang, B N; Kao, Y S; Lu, K S

    1994-11-01

    The ultrastructure and cytochemistry of the gerbil pineal gland were studied by the conventional electron microscopy, zinc iodide-osmium tetroxide (ZIO) staining and chromaffin reaction. Conventional electron microscopy revealed that the ultrastructure of gerbil pinealocytes are similar to other rodents, i.e., irregular cell contour with numerous cytoplasmic processes, round or oval nucleus and prominent nucleoli, elongated mitochondria with flattened and tubular cristae and dense matrix, well-developed Golgi apparatus and its associated structures, abundant elements of endoplasmic reticulum--both smooth and rough varieties, and bundles of microfilament and microtubule in the cytoplasm. Some pinealocyte processes contain numerous small clear and "slightly coated" vesicles. Numerous profiles of varicosities containing small dense-cored and clear vesicles were frequently encountered. After ZIO treatment, ZIO staining was preferentially localized in the cytoplasm of some, but not all, of the gerbil pinealocytes. Numerous small clear vesicles (30-50 nm in diameter) in the process of the pinealocytes or in the varicosities of the nerve fibers showed strong ZIO-philia. After chromaffin reaction treatment, the number and electron density of small clear and dense-cored vesicles in the profiles of nerve varicosities increased and this indicates that some of the small clear and dense-cored vesicles in the varicosities are reactive. It is thus concluded that (1) the vesicles in the pinealocytes may be rich in cystine and/or cysteine and possibly the organelle is involved in the sequestering calcium ion during the calcification of the pineal concretions, and (2) the small dense-cored and clear vesicles in the nerve fibers in the gerbil pineal parenchyma may contain both serotonin and primary biogenic amines. PMID:7530780

  17. H pylori infection causes chronic pancreatitis in Mongolian gerbils

    PubMed Central

    Rieder, Gabriele; Karnholz, Arno; Stoeckelhuber, Mechthild; Merchant, Juanita L; Haas, Rainer

    2007-01-01

    AIM: To investigate whether chronic H pylori infection has the potential to induce pancreatitis in the Mongolian gerbil model, and whether it is dependent on an intact type IV secretion system. METHODS: Mongolian gerbils were infected with wild type (WT) H pylori typeIstrain B128 or its isogenic mutant B128 ΔcagY (defective type IV secretion). After seven months of infection, H pylori was reisolated from antrum and corpus and H pylori DNA was analyzed by semi-nested polymerase chain reaction (PCR). Inflammation and histological changes were documented in the gastric antrum, corpus, and pancreas by immunohistochemistry. Cytokine mRNA, gastric pH, plasma gastrin, amylase, lipase, and glucose levels were determined. RESULTS: The H pylori infection rate was 95%. Eight infected animals, but none of the uninfected group, developed transmural inflammation and chronic pancreatitis. Extensive interstitial fibrosis and inflammation of the pancreatic lobe adjacent to the antrum was confirmed by trichrome stain, and immuno-histochemically. Pro-inflammatory cytokine mRNA was significantly increased in the antral mucosa of all infected gerbils. In the corpus, only cytokine levels of WT-infected animals and those developing transmural inflammation and pancreatitis were significantly increased. Levels of lipase, but not glucose or amylase levels, were significantly reduced in the pancreatitis group. H pylori DNA was detected in infected antral and corpus tissue, but not in the pancreas. CONCLUSION: H pylori infection is able to induce chronic pancreatitis in Mongolian gerbils independently of the type IV secretion system, probably by an indirect mechanism associated with a penetrating ulcer. PMID:17663507

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

    PubMed

    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. PMID:26045450

  19. Protection of gerbils from amebic liver abscess by immunization with a recombinant Entamoeba histolytica antigen.

    PubMed Central

    Zhang, T; Cieslak, P R; Stanley, S L

    1994-01-01

    Amebiasis, infection by the intestinal protozoan parasite Entamoeba histolytica, is a leading parasitic cause of death. As a step in the development of a recombinant antigen vaccine to prevent E. histolytica infection, we looked at the ability of a recombinant version of the serine-rich E. histolytica protein (SREHP) to elicit a protective immune response against invasive amebic disease. Gerbils, a standard model for amebic liver abscess, were immunized with either a recombinant SREHP/maltose-binding protein (MBP) fusion, recombinant MBP alone, or phosphate-buffered saline (PBS), all combined with complete Freund's adjuvant. In the first trial (group 1), gerbils received a primary and two booster immunizations intraperitoneally; in the second trial (group 2), gerbils were immunized by a single intradermal injection. SREHP/MBP-immunized gerbils in both groups produced antibody to native SHEHP and developed delayed-type hypersensitivity responses to recombinant SREHP. All gerbils were challenged by an intrahepatic injection with 5 x 10(4) virulent E. histolytica HM1-IMSS trophozoites. Complete protection from amebic liver abscess was seen in 64% of the SHEHP/MBP-immunized gerbils in group 1 and in 100% of the SREHP/MBP-immunized gerbils in group 2. There was no protection observed in MBP- or PBS-immunized gerbils in either group. Our results indicate that the SREHP molecule has potential as a vaccine to prevent amebic infection and demonstrate that successful vaccination of animals with recombinant E. histolytica antigen vaccines is possible. Images PMID:8132322

  20. Lack of Negative Effects on Syrian Hamsters and Mongolian Gerbils Housed in the Same Secondary Enclosure

    PubMed Central

    Pritchett-Corning, Kathleen R; Gaskill, Brianna N

    2015-01-01

    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. PMID:26045450

  1. Draft Genome Sequence of Gerbil-Adapted Carcinogenic Helicobacter pylori Strain 7.13.

    PubMed

    Asim, Mohammad; Chikara, Surendra K; Ghosh, Arpita; Vudathala, Srinivas; Romero-Gallo, Judith; Krishna, Uma S; Wilson, Keith T; Israel, Dawn A; Peek, Richard M; Chaturvedi, Rupesh

    2015-01-01

    We report here the draft genome sequence of Helicobacter pylori strain 7.13, a gerbil-adapted strain that causes gastric cancer in gerbils. Strain 7.13 is derived from clinical strain B128, isolated from a patient with a duodenal ulcer. This study reveals genes associated with the virulence of the strain. PMID:26067974

  2. Seasonal variations of androgens and of several sexual parameters in male Meriones shawi in southern Morocco.

    PubMed

    Zaime, A; Laraki, M; Gautier, J Y; Garnier, D H

    1992-05-01

    Seasonal changes of several parameters related to sexual activity were studied in the gerbil (Rodentia: Gerbillidae). The weight of the testes, seminal vesicles, and adrenals fluctuate throughout the year. Plasma androgen levels and histological aspect of the testes also vary throughout the year. Spermatogonial and steroid activities are synchronous and are maximal in winter and spring. The relationship between these activities and environmental climatic parameters is discussed: the beginning of sexual activity seems correlated with the first rains. PMID:1601278

  3. Radon inhalation protects against transient global cerebral ischemic injury in gerbils.

    PubMed

    Kataoka, Takahiro; Etani, Reo; Takata, Yuji; Nishiyama, Yuichi; Kawabe, Atsushi; Kumashiro, Masayuki; Taguchi, Takehito; Yamaoka, Kiyonori

    2014-10-01

    Although brain disorders are not the main indication for radon therapy, our previous study suggested that radon inhalation therapy might mitigate brain disorders. In this study, we assessed whether radon inhalation protects against transient global cerebral ischemic injury in gerbils. Gerbils were treated with inhaled radon at a concentration of 2,000 Bq/m(3) for 24 h. After radon inhalation, transient global cerebral ischemia was induced by bilateral occlusion of the common carotid artery. Results showed that transient global cerebral ischemia induced neuronal damage in hippocampal CA1, and the number of damaged neurons was significantly increased compared with control. However, radon treatment inhibited ischemic damage. Superoxide dismutase (SOD) activity in the radon-treated gerbil brain was significantly higher than that in sham-operated gerbils. These findings suggested that radon inhalation activates antioxidative function, especially SOD, thereby inhibiting transient global cerebral ischemic injury in gerbils. PMID:24792782

  4. In vivo metabolism of CCl sub 4 by gerbils pretreated with chlordecone, phenobarbital, or mirex

    SciTech Connect

    Cai, Z.; Mehendale, H.M. )

    1990-02-26

    Gerbils are known to be much more sensitive to CCl{sub 4} lethality than rats as indicated by 48 hours LD{sub 50} (0.08 vs 2.8 ml/kg). On the other hand, gerbils are refractory to chlordecone (CD) potentiation of CCl{sub 4} toxicity. To investigate the possible mechanism underlying gerbil's high sensitivity to CCl{sub 4} lethality, the authors studied in vivo metabolism of CCl{sub 4} in gerbils pretreated with dietary CD (10 ppm), phenobarbital (PB, 225 ppm) or mirex (M, 10 ppm). The hepatic content of CCl{sub 4}, the expiration of {sup 14}CCl{sub 4} and {sup 14}CCl{sub 4}-derived Co{sub 2}, and lipid peroxidation were measured and the results were compared with our previous data for rats. After 15-day dietary pretreatment, male gerbils (60-80 g) received {sup 14}CCl{sub 4} (80 ml/kg; sp act: 0.04 mCi/mmol) ip in corn oil and the expired air was collected for 6 hours. More than 80% of the dose administered was expired as parent compound in 6 hours regardless of pretreatments. Expiration of {sup 14}CCl{sub 4} derived {sup 14}CO{sub 2} in control gerbils was 3.5-fold more than in control rats and was increased significantly in pretreated gerbils (M>PB>CD). PB and M pretreatments resulted in significant increase of {sup 14}C label bound to non-lipid fraction of hepatic content as compared with CD or control gerbils. The radiolabel present in hepatic content of control gerbils was 5-fold higher than that of control rats. In vivo liquid peroxidation measured as diene conjugation in lipid extracts from the livers was lower in gerbils than in rats, and there were no significant differences among control and pretreated gerbils. These data indicate that the more extensive metabolism of CCl{sub 4} in gerbils may partially explain their high sensitivity to CCl{sub 4} toxicity. However, the significantly enhanced metabolism of CCl{sub 4} found in CD, PB, or M pretreated gerbils did not lead to amplification of CCl{sub 4} hepatotoxic and lethal effects.

  5. Susceptibility to acoustic trauma in young and aged gerbils

    NASA Astrophysics Data System (ADS)

    Boettcher, Flint A.

    2002-12-01

    The effect of age on susceptibility to noise-induced hearing loss (NIHL), the effect of gender on the interaction of age-related hearing loss (ARHL) and NIHL, and the relative contributions of ARHL and NIHL to total hearing loss are poorly understood. The issues are difficult to resolve empirically in human subjects because of lack of control over extrinsic variables and for ethical reasons. Accordingly, these issues were examined in a well-studied animal model of both ARHL and NIHL, the Mongolian gerbil. Animals were exposed to an intense tone (3.5 kHz, 113 dB SPL, 1 h) either as young adults (6-8 months) or near the end of the average lifespan of the species (34-38 months). Hearing thresholds were determined with the auditory brainstem response (ABR). ARHL was approximately 5-10 dB, with slightly more observed in males at 16 kHz (p<0.05). NIHL of approximately 15-20 dB was similar for the young and old groups, suggesting no differences in susceptibility as a function of age. There were no gender differences in NIHL. The relative contributions of ARHL and NIHL to total hearing loss in aged, noise-exposed gerbils were predicted by an addition of ARHL and NIHL in dB, similar to an international standard on hearing loss allocation, ISO-1999 [Determination of Occupational Noise Exposure and Estimation of Noise-Induced Hearing Impairment (1990)]. Previous evaluations of ISO-1999 using the gerbil animal model concluded that addition of ARHL and NIHL in dB overpredicts total hearing loss. However, in these studies, ARHL was large and nearly equal to NIHL. In the current study, where ARHL was much less than NIHL, addition of the two factors in dB, as recommended by ISO-1999, results in fairly accurate predictions of total hearing loss.

  6. Mechanics of the Unusual Basilar Membrane in Gerbil

    NASA Astrophysics Data System (ADS)

    Kapuria, Santosh; Steele, Charles R.; Puria, Sunil

    2011-11-01

    The basilar membrane in gerbil differs from most other mammals, since its width and thickness show little variation from base to apex, and tympanic fiber layer in the pectinate zone forms a pronounced arch. Measurements indicate a quadratically increasing stiffness under point loading, which is contrary to the expected behavior of an arch. The plateau value has been considered to be the physiologically relevant stiffness, but it only occurs after 10-25 μm of deflection, whereas the normal physiological deflection is in the submicron range. The present work aims to resolve these contradictions by considering the mechanics of the geometric configuration.

  7. Development of wide-band middle ear transmission in the Mongolian gerbil

    NASA Astrophysics Data System (ADS)

    Overstreet, Edward H.; Ruggero, Mario A.

    2002-01-01

    Stapes vibrations were measured in deeply anesthetized adult and neonatal (ages: 14 to 20 days) Mongolian gerbils. In adult gerbils, the velocity magnitude of stapes responses to tones was approximately constant over the entire frequency range of measurements, 1 to 40 kHz. Response phases referred to pressure near the tympanic membrane varied approximately linearly as a function of increasing stimulus frequency, with a slope corresponding to a group delay of 30 μs. In neonatal gerbils, the sensitivity of stapes responses to tones was lower than in adults, especially at mid-frequencies (e.g., by about 15 dB at 10-20 kHz in gerbils aged 14 days). The input impedance of the adult gerbil cochlea, calculated from stapes vibrations and published measurements of pressure in scala vestibuli near the oval window [E. Olson, J. Acoust. Soc. Am. 103, 3445-3463 (1998)], is principally dissipative at frequencies lower than 10 kHz. Conclusions: (a) middle-ear vibrations in adult gerbils do not limit the input to the cochlea up to at least 40 kHz, i.e., within 0.5 oct of the high-frequency cutoff of the behavioral audiogram; and (b) the results in both adult and neonatal gerbils are inconsistent with the hypothesis that mass reactance controls high-frequency ossicular vibrations and support the idea that the middle ear functions as a transmission line.

  8. Gerbils exhibit stable open-arms exploration across repeated testing on the elevated plus-maze.

    PubMed

    Rico, Javier Leonardo; Penagos-Gil, Marion; Castañeda, Anderson F; Corredor, Karen

    2016-01-01

    Repeated testing on the elevated plus-maze (EPM) leads rats and mice to avoid the open-arms of the apparatus. The effect of multiple exposures to the EPM on the behavioral profile of gerbils is unknown. In this study, young and middle-aged gerbils were exposed to the EPM and four retests were carried out 24, 48, 72 and 96h after the first trial in order to determine whether animals exhibited open-arms avoidance. In addition, groups of young and middle-aged gerbils were exposed to the EPM for 20-min followed by a 5-min retest trial 24h apart to analyze the effect of a prolonged exposure to the EPM on open-arms exploration during first trial and retest. Gerbils exhibited high exploration of open-arms during the first trial and progressive locomotor decrease across repeated testing. Unlike previous reports for rats and mice, young gerbils showed a stable open-arms exploration both across multiple exposures and during a prolonged exposure to EPM. Middle-aged gerbils also exhibited a stable open-arms exploration during retest prior to the 20-min test. Results suggest a reliable repeated test paradigm for the EPM using our proposed methodology for gerbils. PMID:26621258

  9. Laboratory tests of seven rodenticides for the control of Meriones shawi.

    PubMed Central

    Gill, J. E.; Redfern, R.

    1983-01-01

    The response of Meriones shawi to seven rodenticides was investigated in laboratory feeding tests. The species proved to be much less susceptible to anticoagulants than most other species of rodent pests. Brodifacoum (at 0.005%), although giving complete mortality after only 8 days' continuous feeding, was more toxic than warfarin (0.025%), coumatetralyl (0.0375%), difenacoum (0.005%) and bromadiolone (0.005%). Calciferol (0.1%), though toxic, was significantly unpalatable. Zinc phosphide (5.0%) presented for 2 days in a choice test against unpoisoned food gave 80% mortality and appears to be the most suitable of these compounds for the control of M. shawi in the field. PMID:6605985

  10. Laboratory tests of seven rodenticides for the control of Meriones shawi.

    PubMed

    Gill, J E; Redfern, R

    1983-10-01

    The response of Meriones shawi to seven rodenticides was investigated in laboratory feeding tests. The species proved to be much less susceptible to anticoagulants than most other species of rodent pests. Brodifacoum (at 0.005%), although giving complete mortality after only 8 days' continuous feeding, was more toxic than warfarin (0.025%), coumatetralyl (0.0375%), difenacoum (0.005%) and bromadiolone (0.005%). Calciferol (0.1%), though toxic, was significantly unpalatable. Zinc phosphide (5.0%) presented for 2 days in a choice test against unpoisoned food gave 80% mortality and appears to be the most suitable of these compounds for the control of M. shawi in the field. PMID:6605985

  11. Effects of alpha-chlorohydrin and gonadectomy on the adenohypophysial cells of male rats and gerbils.

    PubMed

    Dixit, V P; Lohiya, N K; Jain, H C

    1974-05-01

    The cytological changes occurring in the gonadotropic cells of the anterior lobe of the pituitary in 30 male rats and 30 male gerbils after administration of alpha-chlorohydrin were compared with those occurring following bilateral gonadectomy. A decline in the weights of testes and accessory sex glands and inhibited spermatogenesis were noted in rats and gerbils following alpha-chlorohydrin administration. Alpha-cholorohydrin changed the appearance of the delta-basilphils, cell cytoplasm showed fine granulation and vacuolization, and castration vacuoles appeared in many delta-basiphils of the anteroir lobe of the pituitary. The compound brought about transient changes resembling those of castration in the anterior lobe of the pituitary of male rats and gerbils. In gerbils, there was also a marked decrease in the number of acidophils. The results show that alpha-chlorohydrin exerts its effects on androgen-dependent structures, e.g., seminal vesicles, ventral prostrate, epididymides, and perineal complex. PMID:4841391

  12. Bisphenol-A promotes antiproliferative effects during neonatal prostate development in male and female gerbils.

    PubMed

    de Lima, Rodrigo Fernandes; Rodriguez, Daniel Andrés Osório; Campos, Mônica Souza; Biancardi, Manoel Francisco; dos Santos, Iana Figueiredo Ferreira Roriz; de Oliveira, Wendyson Duarte; Cavasin, Gláucia Maria; Marques, Mara Rubia; Taboga, Sebastião Roberto; Santos, Fernanda Cristina Alcantara

    2015-12-01

    The aim of this study was to evaluate the development of male and female neonatal gerbil prostate under normal conditions and exposed to bisphenol-A (BPA). Normal postnatal development of the female gerbil prostate occurs earlier than and is morphologically distinct from that occurring in males. In BPA-exposed PND8 gerbils, we have not observed evidence of alterations in the ductal branching in either gender. However, the exposure to BPA alters the immunolabeling pattern of AR, ERα, and PCNA. In males, the exposure to high dosages of BPA resulted in a decrease in the proliferative status of the developing ventral prostate. In females, both high and low dosages were sufficient to decrease the proliferation of paraurethral buds in the branching process by more than 50%. Therefore, the obtained data indicate that BPA promotes antiproliferative effects during the neonatal development of the gerbil prostate, with more sensitivity to this endocrine disruptor in females. PMID:26529182

  13. Characteristic, polymorphism and expression distribution of LCAT gene in a Mongolian gerbil model for hyperlipidemia.

    PubMed

    Liu, Yue huan; Wu, Jiu sheng; Wang, Zhi yuan; Yu, Chen huan; Ying, Hua zhong; Xu, Ning ying

    2014-10-01

    This study aims to evaluate the genetic basis and activity of lecithin cholesterol acyltransferase (LCAT) in a novel Mongolian gerbil model for hyperlipidemia. Gerbils may be susceptible to high fat and cholesterol (HF/HC) diets, which can rapidly lead to the development of hyperlipidemia. Approximately 10-30% of gerbils that are over 8months old and fed controlled diets spontaneously develop hyperlipidemia. Using the HF/HC diet model, we detected triglycerides (TG), total cholesterol (TC), HDL (high density lipoprotein)-C, LDL (low density lipoprotein)-C and LCAT in both old (>8months) and young gerbils. The TC and HDL-C levels were two times higher in old gerbils compared with young gerbils (P<0.01). However, in the old group the LCAT activity fell slightly compared with the normal lipidemia group. It is reasonable to hypothesize that this may be associated with single nucleotide polymorphisms of the LCAT gene. We cloned this gene to investigate the sensitivity of the gerbil to the HF/HC diet and spontaneous hyperlipidemia. The entire LCAT gene was cloned by splicing sequences of RACE (rapid amplification of cDNA ends) and nest-PCR products (AN: KC533867.1). The results showed that the 3683base pair gene consists of six exons and five introns. The LCAT protein consists of 444 amino acid (AA) residues, which are analogous to the human LCAT gene, and includes 24 signal peptide AA and 420 mature protein AA. Expression of LCAT was detected in the kidney, spleen and adrenal tissue, apart from the liver, by immunohistochemistry. The abundance of the protein was greater in the older group compared with the control group. Polymorphisms were analyzed by PCR-SSCP (PCR-single-strand conformation polymorphism) but none were found in 444 animals of the ZCLA closed population (a Chinese cultured laboratory gerbil population). PMID:25036405

  14. Hematologic Assessment in Pet Rats, Mice, Hamsters, and Gerbils: Blood Sample Collection and Blood Cell Identification.

    PubMed

    Lindstrom, Nicole M; Moore, David M; Zimmerman, Kurt; Smith, Stephen A

    2015-09-01

    Hamsters, gerbils, rats, and mice are presented to veterinary clinics and hospitals for prophylactic care and treatment of clinical signs of disease. Physical examination, history, and husbandry practice information can be supplemented greatly by assessment of hematologic parameters. As a resource for veterinarians and their technicians, this article describes the methods for collection of blood, identification of blood cells, and interpretation of the hemogram in mice, rats, gerbils, and hamsters. PMID:26297409

  15. Hematologic assessment in pet rats, mice, hamsters, and gerbils: blood sample collection and blood cell identification.

    PubMed

    Lindstrom, Nicole M; Moore, David M; Zimmerman, Kurt; Smith, Stephen A

    2015-01-01

    Hamsters, gerbils, rats, and mice are presented to veterinary clinics and hospitals for prophylactic care and treatment of clinical signs of disease. Physical examination, history, and husbandry practice information can be supplemented greatly by assessment of hematologic parameters. As a resource for veterinarians and their technicians, this article describes the methods for collection of blood, identification of blood cells, and interpretation of the hemogram in mice, rats, gerbils, and hamsters. PMID:25421023

  16. Effects of basilar membrane arch and radial tension on the travelling wave in gerbil cochlea.

    PubMed

    Chan, Wei Xuan; Yoon, Yong-Jin

    2015-09-01

    The basilar membrane velocity of gerbil cochlea showed discrepancy between theoretical model and experimental measurements. We hypothesize that the reasons of such discrepancies are due to the arch towards the scala tympani and radial tension present in the basilar membrane of the gerbil cochlea. The arch changes the bending stiffness in the basilar membrane, reduces the effective fluid force on the membrane and increases the basilar membrane's inertia. The existence of the radial tension also dampens the acoustic travelling wave. In this paper, the wave number functions along the gerbil basilar membrane are calculated from experimentally measured physical parameters with the theoretical model as well as extracted from experimentally measured basilar membrane velocity with the wave number inversion formula. The two wave number functions are compared and the effects of the tension and membrane arch on the wave number are studied based on various parameters of the model. We found that the bending stiffness across the gerbil basilar membrane varies (1-2 orders along the cochlea in the section 2.2 mm-3 mm from base) more than the calculated value in the flat basilar membrane model and the radial tension increases the damping of the travelling wave in gerbil cochlea significantly (5 times more than that without radial tension). These effects of arch and radial tension in the basilar membrane elucidate the discrepancy between previous theoretical model and experimental measurements in gerbil cochlea. PMID:26070425

  17. Conservation genetics of a rare Gerbil species: a comparison of the population genetic structures and demographic histories of the locally rare Pygmy Gerbil and the common Anderson's Gerbil

    PubMed Central

    2010-01-01

    Background One of the major challenges in evolutionary biology is identifying rare species and devising management plans to protect them while also sustaining their genetic diversity. However, in attempting a broad understanding of rarity, single-species studies provide limited insights because they do not reveal whether the factors that affect rare species differ from those that affect more common species. To illustrate this important concept and to arrive at a better understanding of the form of rarity characterizing the rare Gerbillus henleyi, we explored its population genetic structure alongside that of the locally common Gerbillus andersoni allenbyi. We trapped gerbils in several locations in Israel's western and inner Negev sand dunes. We then extracted DNA from ear samples, and amplified two mitochondrial sequences: the control region (CR) and the cytochrome oxidase 2 gene (CO2). Results Nucleotide diversity was low for all sequences, especially for the CR of G. a. allenbyi, which showed no diversity. We could not detect any significant population genetic structure in G. henleyi. In contrast, G. a. allenbyi's CO2 sequence showed significant population genetic structure. Pairwise PhiPT comparisons showed low values for G. henleyi but high values for G. a. allenbyi. Analysis of the species' demographic history indicated that G. henleyi's population size has not changed recently, and is under the influence of an ongoing bottleneck. The same analysis for G. a. allenbyi showed that this species has undergone a recent population expansion. Conclusions Comparing the two species, the populations of G. a. allenbyi are more isolated from each other, likely due to the high habitat specificity characterizing this species. The bottleneck pattern found in G. henleyi may be the result of competition with larger gerbil species. This result, together with the broad habitat use and high turnover rate characterizing G. henleyi, may explain the low level of differentiation

  18. Acomys, the closest relatives to Gerbils, do express Pdx-1 protein and have similar islet morphology to Gerbils.

    PubMed

    Gustavsen, Carsten R; Kvicerova, Jana; Dickinson, Hayley; Heller, R Scott

    2009-01-01

    Acomys, also called spiny mice, were once used as a diabetes model. We have recently demonstrated that the closest relatives to the Acomys, members of the family Gerbillinae, lack the transcription factor Pdx-1. Therefore, we sought to determine if members of this family also lack Pdx-1, and describe the pancreatic morphology in three different species of Acomys: Acomys cahirinus (Egyptian spiny mouse), Acomys cilicicus (Asia Minor spiny mouse) and Acomys dimidiatus (eastern spiny mouse). We successfully cloned the Acomys Pdx-1 gene and we demonstrate by immunocytochemistry that the Pdx-1 protein is expressed in the pancreatic insulin immunoreactive cells and in a subset of the somatostatin cells. The basic islet structure is very similar to other rodents - with the insulin cells in the center, and glucagon, somatostatin, PP and occasional PYY cells in the periphery. No ghrelin or CART cells were identified. Nkx6.1 was localized specifically to the insulin immunoreactive cells, while Nkx2.2 was found in all endocrine cells except the somatostatin immunoreactive cells. Both MafA and MafB were expressed in the islets; MafA being specific for the insulin cells, while MafB was primarily in the glucagon cells but also found in some insulin cells. Isl-1 was localized in all endocrine cell types. In conclusion, the closest relatives to the Gerbils express a Pdx-1 protein that is 90% similar to other rodents but also has a unique 3 amino acid insert compared to other species.  During the evolution of the spiny mice and the gerbils, it appears that the Pdx-1 gene was lost. PMID:21099272

  19. Hypolipidemic and hypocholesterolemic effect of argan oil (Argania spinosa L.) in Meriones shawi rats.

    PubMed

    Berrougui, H; Ettaib, A; Herrera Gonzalez, M D; Alvarez de Sotomayor, M; Bennani-Kabchi, N; Hmamouchi, M

    2003-11-01

    The potential health benefits of various dietary oils in relation to cardiovascular disease and cancer are recently receiving considerable attention. The main proposal of this study is to investigate the effect of dietary argan oil, obtained from seeds of Argania spinosa L. (Sapotaceae) endemic from Morocco, on serum lipids composition. Hyperlipidemia was induced by high calorie and cholesterol (HCC) diet administration in 16 rats (Meriones shawi, a rodent of the Gerbillideae family). Eight rats were treated with argan oil (1ml/100g weight) daily by oral route during 7 weeks (treated group). Control animals were also fed with HCC diet for 7 weeks. After 7-week treatment with argan oil, blood lipoproteins were significantly reduced. Total cholesterol decreased with 36.67% (P<0.01), low density lipoprotein (LDL)-cholesterol in 67.70% (P<0.001), triglycerides in 30.67% (P<0.05) and body weight in 12.7% (P<0.05). High density lipoprotein (HDL)-cholesterol concentration remained unaltered. These results indicate the beneficial effect of argan oil in the treatment of the hyperlipidemia and hypercholesterolemia. This effect will be related with the polyunsaturated fatty acids and other constituents of studied oil. PMID:14522427

  20. Spatial distribution and ecological environment analysis of great gerbil in Xinjiang Plague epidemic foci based on remote sensing

    NASA Astrophysics Data System (ADS)

    Gao, Mengxu; Li, Qun; Cao, Chunxiang; Wang, Juanle

    2014-03-01

    Yersinia pestis (Plague bacterium) from great gerbil was isolated in 2005 in Xinjiang Dzungarian Basin, which confirmed the presence of the plague epidemic foci. This study analysed the spatial distribution and suitable habitat of great gerbil based on the monitoring data of great gerbil from Chinese Center for Disease Control and Prevention, as well as the ecological environment elements obtained from remote sensing products. The results showed that: (1) 88.5% (277/313) of great gerbil distributed in the area of elevation between 200 and 600 meters. (2) All the positive points located in the area with a slope of 0-3 degree, and the sunny tendency on aspect was not obvious. (3) All 313 positive points of great gerbil distributed in the area with an average annual temperature from 5 to 11 °C, and 165 points with an average annual temperature from 7 to 9 °C. (4) 72.8% (228/313) of great gerbil survived in the area with an annual precipitation of 120-200mm. (5) The positive points of great gerbil increased correspondingly with the increasing of NDVI value, but there is no positive point when NDVI is higher than 0.521, indicating the suitability of vegetation for great gerbil. This study explored a broad and important application for the monitoring and prevention of plague using remote sensing and geographic information system.

  1. Everybody loses: intraspecific competition induces tragedy of the commons in Allenby's gerbils.

    PubMed

    Berger-Tal, Oded; Embar, Keren; Kotler, Burt P; Saltz, David

    2015-01-01

    Interference competition may lead to a tragedy of the commons in which individuals driven by self-interest reduce the fitness of the entire group. We investigated this hypothesis in Allenby's gerbils, Gerbillus andersoni allenbyi, by comparing foraging behaviors of single vs. pairs of gerbils. We recorded strong interference competition within the foraging pairs. Competition reduced the amount of time the gerbils spent foraging, as well as foraging efficiency since part of the foragers' attention was directed toward detecting competitors (apparent predation risk). Single gerbils harvested significantly more food than the combined efforts of two gerbils foraging together. Competition reduced the success of both individuals within a pair by more than 50%, making this a case of the tragedy of the commons where each individual's investment in competition reduces the success of all individuals within the group, including its own. Despite their great costs, competitive behaviors will be selected for as long as one individual achieves higher fitness than the other. In nature, interspecific interactions, such as predation risk, may act to reduce and regulate the deleterious effects of intraspecific competition. PMID:26236890

  2. Ultrastructural study of host-parasite relationship and pathogenicity of Eimeria sp. infecting Libyan Jird (Meriones libycus) (Lichtenstein, 1828).

    PubMed

    Kassem, Hamed H; Nass, Sedigh Ahmed

    2013-04-01

    The relationship of Eimeria sp. and its host fat LibyanJird (Meriones libycus) was studied on an ultrastructural level. The host cellular organelles (nucleus, mitochondria, endoplasmic reticulum and golgi apparatus) and the changes of its infected intestinal epithelial cells during the development of parasitic stages (schizogony and gamogony) were studied and compared with those non-infected cells. The ultrastructures of intravacuolar tubules and folds in the parasitophorous vacuole (P.V.) were described. These fine structures may involve in the transporttation of materials from the host cell to across the parasitovorous vacuole (P.V.). PMID:23697012

  3. Viability staining and animal infectivity of Cryptosporidium andersoni oocysts after long-term storage.

    PubMed

    Kvác, Martin; Kvetonová, Dana; Salát, Jirí; Ditrich, Oleg

    2007-01-01

    Preservation of biological properties of oocysts during the storage is critical for experimental work. Stomach species of cryptosporidia are less resistant against external influences, and their infectivity decreases rapidly in comparison with intestinal cryptosporidia. Cryptosporidium andersoni oocysts lost their infectivity for gerbil (Meriones unguiculatus) after 7 months storage in deionised water (DW) or in 2.5% potassium dichromate solution (PDS). Evaluation of oocyst viability by flow cytometry indicates higher percentage of viable oocysts stored in PDS than in DW, particularly after 6 months of storage. However, direct counting using fluorescent microscope revealed that these results are false and are influenced by the change of staining properties during the storage in PDS. Moreover, the examination of oocyst integrity by flow cytometry revealed that oocysts preserved in PDS kept their wall integrity longer than those stored in DW, and this fact should be taken into consideration during quantification of oocyst survival. PMID:17024363

  4. Inverse relationship between adult hippocampal cell proliferation and synaptic rewiring in the dentate gyrus.

    PubMed

    Butz, Markus; Teuchert-Noodt, Gertraud; Grafen, Keren; van Ooyen, Arjen

    2008-01-01

    Adult neurogenesis is a key feature of the hippocampal dentate gyrus (DG). Neurogenesis is accompanied by synaptogenesis as new cells become integrated into the circuitry of the hippocampus. However, little is known to what extent the embedding of new neurons rewires the pre-existing network. Here we investigate synaptic rewiring in the DG of gerbils (Meriones unguiculatus) under different rates of adult cell proliferation caused by different rearing conditions as well as juvenile methamphetamine treatment. Surprisingly, we found that an increased cell proliferation reduced the amount of synaptic rewiring. To help explain this unexpected finding, we developed a novel model of dentate network formation incorporating neurogenesis and activity-dependent synapse formation and remodelling. In the model, we show that homeostasis of neuronal activity can account for the inverse relationship between cell proliferation and synaptic rewiring. PMID:18481284

  5. Eradication of enteric helicobacters in Mongolian gerbils is complicated by the occurrence of Clostridium difficile enterotoxemia.

    PubMed

    Bergin, Ingrid L; Taylor, Nancy S; Nambiar, Prashant R; Fox, James G

    2005-06-01

    Outbred Mongolian gerbils from a United States commercial source were examined for colonization with naturally occurring enterohepatic Helicobacter spp. Helicobacter spp. were identified in the cecum and colon by culture and by using genus-specific primers in polymerase chain reaction (PCR) assays. Nutritionally balanced triple-antibiotic wafers (containing amoxicillin, metronidazole, and bismuth) used previously to eliminate helicobacter infections in mice were administered in an attempt to eradicate the naturally occurring novel helicobacters in the gerbils. After 7 days of antibiotic treatment, two of the experimental animals died due to Clostridium difficile-associated enterotoxemia. However, at 3 weeks after antibiotic cessation, the surviving three animals had no Helicobacter spp. in the cecum or colon according to PCR analysis. Eradication of Helicobacter spp. using dietary administration of antibiotics was complicated by the presence of toxin-producing C. difficile. An alternate method to develop helicobacter-free gerbils (such as Caesarian rederivation) may be necessary. PMID:16089175

  6. Minocycline Protection of Neomycin Induced Hearing Loss in Gerbils

    PubMed Central

    Robinson, Alan M.; Vujanovic, Irena; Richter, Claus-Peter

    2015-01-01

    This animal study was designed to determine if minocycline ameliorates cochlear damage is caused by intratympanic injection of the ototoxic aminoglycoside antibiotic neomycin. Baseline auditory-evoked brainstem responses were measured in gerbils that received 40 mM intratympanic neomycin either with 0, 1.2, or 1.5 mg/kg intraperitoneal minocycline. Four weeks later auditory-evoked brainstem responses were measured and compared to the baseline measurements. Minocycline treatments of 1.2 mg/kg and 1.5 mg/kg resulted in significantly lower threshold increases compared to 0 mg/kg, indicating protection of hearing loss between 6 kHz and 19 kHz. Cochleae were processed for histology and sectioned to allow quantification of the spiral ganglion neurons and histological evaluation of organ of Corti. Significant reduction of spiral ganglion neuron density was demonstrated in animals that did not receive minocycline, indicating that those receiving minocycline demonstrated enhanced survival of spiral ganglion neurons, enhanced survival of sensory hairs cells and spiral ganglion neurons, and reduced hearing threshold elevation correlates with minocycline treatment demonstrating that neomycin induced hearing loss can be reduced by the simultaneous application of minocycline. PMID:25950003

  7. Ulinastatin inhibits cerebral ischemia-induced apoptosis in the hippocampus of gerbils.

    PubMed

    Cho, Young-Sam; Shin, Mal-Soon; Ko, Il-Gyu; Kim, Sung-Eun; Kim, Chang-Ju; Sung, Yun-Hee; Yoon, Hye-Sun; Lee, Bong-Jae

    2015-08-01

    Ulinastatin is a urinary trypsin inhibitor, originally extracted and purified from human urine. Ulinastatin has cytoprotective effects against ischemic injury in several organs. In the present study, the neuroprotective effects of ulinastatin following ischemic cerebral injury in the hippocampus of gerbils was investigated. To induce transient global ischemia in gerbils, the common carotid arteries were occluded using aneurysm clips for 5 min, and the clips were then removed. Ulinastatin was subcutaneously injected into the gerbils once a day for 7 days at doses of 50,000 or 100,000 U/kg. The gerbils were confronted with a step-down avoidance task, following which tissue samples from the gerbils were examined using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, western blot analysis for B-cell lymphoma (Bcl-2) and Bcl-2-associated X protein (Bax), immunohistochemistry for caspase-3 and immunofluorescence for 5-bromo-2'-deoxyuridine. The numbers of TUNEL-positive and caspase-3-positive cells in the hippocampal CA1 region increased following cerebral ischemia. The expression of Bax in the hippocampus increased, while the expression of Bcl-2 in the hippocampus decreased following cerebral ischemia. These results confirmed that apoptosis in the hippocampus was enhanced following cerebral ischemia in gerbils. The levels of cell proliferation in the hippocampal dentate gyrus were also enhanced by ischemia, which is possibly an adaptive mechanism to compensate for excessive levels of apoptosis. Ulinastatin treatment inhibited ischemia-induced apoptosis by suppressing apoptosis-associated molecules, and thus ameliorated ischemia-induced short-term memory impairment. The cell proliferation in the hippocampus was also suppressed following ulinastatin treatment. These results suggested the use of ulinastatin as a therapeutic agent for patients with cerebral stroke. PMID:25891426

  8. The Mongolian Gerbil: A Robust Model of Helicobacter pylori-Induced Gastric Inflammation and Cancer.

    PubMed

    Noto, Jennifer M; Romero-Gallo, Judith; Piazuelo, M Blanca; Peek, Richard M

    2016-01-01

    The Mongolian gerbil is an efficient, robust, and cost-effective rodent model that recapitulates many features of H. pylori-induced gastric inflammation and carcinogenesis in humans, allowing for targeted investigation of the bacterial determinants and environmental factors and, to a lesser degree, host constituents that govern H. pylori-mediated disease. This chapter discusses means through which the Mongolian gerbil model has been used to define mechanisms of H. pylori-inflammation and cancer as well as the current materials and methods for utilizing this model of microbially induced disease. PMID:27246040

  9. Ovarian function of the Algerian wild Libyan jird, Meriones libycus during seasonal reproductive cycle: histological and immunohistochemical expression.

    PubMed

    Smaï-Hamdidouche, S; Gernigon-Spychalowicz, T; Khammar, F; Exbrayat, J M

    2013-01-01

    Meriones libycus (Libyan jird), a nocturnal Saharan rodent, is characterized by a seasonal reproductive cycle with a short active phase (spring and early summer) and a long resting period (late summer, autumn, winter). Histological and immunohistochemical techniques were performed in order to study the seasonal variations in mature ovaries. During the breeding season, the ovary showed a continuous cyclical activity, the various stages of folliculogenesis from primordial to preovulatory follicles were observed; broken follicles and corpora lutea were also observed. During sexual quiescence, the ovarian cycle was interrupted; anovulation was observed without any corpus luteum. Non mature antral follicles entered the atretic process. Steroid and steroidogenic enzyme activities were studied using indirect immunohistochemistry. 17β-estradiol, progesterone, testosterone hormones and P450 aromatase (P450 arom) were detected in the different components of the ovary and in various stages of healthy and atretic follicles during the seasonal reproductive cycle. Our results indicate that during ovarian folliculogenesis in breeding season steroids hormone and P450 arom present important activities. In comparison with the resting period, steroidogenesis and steroidogenic enzyme activity became less pronounced in the healthy preantral follicle; it seemed that steroid biosynthesis was reduced and could be involved in the stimulation and maintenance of the ovarian structural integrity in early follicle development. In conclusion, the histological and immunohistochemical seasonal variations of ovaries in Meriones libycus support the hypothesis that seasonal fluctuations are indirectly involved in regulating reproduction, inducing significant changes in both ovarian morphology and its hormonal function. PMID:23233063

  10. Does Long-Term Use of Silver Nanoparticles Have Persistent Inhibitory Effect on H. pylori Based on Mongolian Gerbil's Model?

    PubMed Central

    Kuo, Chao-Hung; Lu, Chien-Yu; Yang, Yuan-Chieh; Chin, Chieh; Weng, Bi-Chuang; Liu, Chung-Jung; Chen, Yen-Hsu; Chang, Lin-Li; Kuo, Fu-Chen; Wu, Deng-Chyang; Su, Hong-Lin

    2014-01-01

    Background. It is urgent to find alternative agents due to increasing failure rate of Helicobacter pylori (H. pylori) eradication. The study surveyed the long-term effect of silver nanoparticles (AgNP) on H. pylori based on Mongolian gerbil's model. Materials and Methods. Fifty gerbils were randomly allocated to six groups (A–F). Group (Gr) A: the gerbils were fed with broth; Gr B and D: the gerbils were fed with AgNP/clay complex (0.1% of weight); Gr C and E: the gerbils were fed with AgNP/clay complex(1% of weight); and Gr D, E, and F: the gerbils were inoculated with H. pylori. At the 20th experimental week, the gerbils were sacrificed. Histology was evaluated according to the classification of the Sydney system. P < 0.05 was considered to be statistically significant. Results. The AgNP/clay has more obvious inhibitory effect on H. pylori in vitro. There was a trend of higher concentrations of AgNP with stronger inhibitory effect on H. pylori growth (P = 0.071). There were no significant differences of inflammation among groups D, E, and F (P = 0.688).Conclusion. AgNP/clay would be a potential and safe agent for inhibiting H. pylori. It should be helpful for eradication of H. pylori infection. PMID:24864246

  11. Distribution and morphology of catecholaminergic and serotonergic neurons in the brain of the highveld gerbil, Tatera brantsii.

    PubMed

    Moon, Don-Joon; Maseko, Busisiwe C; Ihunwo, Amadi O; Fuxe, Kjell; Manger, Paul R

    2007-11-01

    The distribution, morphology and nuclear subdivisions of the putative catecholaminergic and serotonergic systems within the brain of the highveld gerbil were identified following immunohistochemistry for tyrosine hydroxylase and serotonin. The aim of the present study was to investigate possible differences in the complement of nuclear subdivisions of these systems when comparing those of the highveld gerbil with those of the laboratory rat. The highveld gerbil was chosen as it is relatively closely related to the laboratory rat, but the Gerbillinae and Murinae lineages diverged over 20 million years ago. Moreover, even though brain sizes are similar, the life history and phenotypes between these two species are substantially different. The gerbils used in the present study were caught from the wild, which is again another contrast to the laboratory rat. While these differences may lead to the prediction of significant differences in the nuclear complement of these systems, we found that all nuclei identified in both systems in the laboratory rat in several earlier studies had direct homologs in the brain of the highveld gerbil. Moreover, there were no additional nuclei in the brain of the highveld gerbil that are not found in the laboratory rat. The only discernable difference between the two species was a greater density and number of catecholaminergic neurons in the olfactory bulb of the highveld gerbil. Thus, the evolution of nuclear parcellation in these systems appears to demonstrate a form of phylogenetic constraint related to the order Rodentia. PMID:17606363

  12. Development of novel microsatellite DNA markers by cross-amplification and analysis of genetic variation in gerbils.

    PubMed

    Du, Xiaoyan; Chen, Zhenwen; Li, Wei; Tan, Yuanqing; Lu, Jing; Zhu, Xiangdong; Zhao, Taiyun; Dong, Gang; Zeng, Lin

    2010-01-01

    The objectives of this study are to establish microsatellite loci for the Mongolian gerbil based on mouse microsatellite DNA sequences and to investigate genetic variation in the laboratory gerbil (Capital Medical University, CMU) and 2 wild gerbil populations (from Yin Chuan city [YIN] and the Hohehot Municipality [HOH]). In total, 536 mouse microsatellite markers were chosen to identify polymorphic dinucleotide repeat loci in the gerbil by cross-amplification. Of these markers, 313 (58.39%) have been discretely amplified from the CMU laboratory gerbil and been sequenced. Of the 313 sequenced markers, 130 were confirmed as simple sequence repeat (SSR) loci in the gerbil. In total, 6 of those newly identified loci plus 6 identified in previous reports were used to estimate the genetic polymorphism for 30 laboratory gerbils and 54 wild gerbils (27 each of the HOH and YIN groups). A total of 29 alleles were observed in the 3 populations, and 11 of 12 loci (91.67%) are polymorphic markers. Nei's standard genetic distances of 0.0592 (CMU vs. HOH) and 0.1033 (CMU vs. YIN) were observed. The averages of observed versus expected heterozygosity are 0.5231/0.4008, 0.5051/0.3882, and 0.4825/0.3665 for the YIN, HOH, and CMU populations, respectively. These results show that cross-amplification using mouse microsatellite primers is an efficient way to identify gerbil SSR loci. By using these 12 selected markers, we have demonstrated that genetic variation level within the CMU population is higher than that has been reported previously and are comparable with the levels found in 2 wild populations. PMID:20525768

  13. Sound coding in the auditory nerve of gerbils.

    PubMed

    Huet, Antoine; Batrel, Charlène; Tang, Yong; Desmadryl, Gilles; Wang, Jing; Puel, Jean-Luc; Bourien, Jérôme

    2016-08-01

    Gerbils possess a very specialized cochlea in which the low-frequency inner hair cells (IHCs) are contacted by auditory nerve fibers (ANFs) having a high spontaneous rate (SR), whereas high frequency IHCs are innervated by ANFs with a greater SR-based diversity. This specificity makes this animal a unique model to investigate, in the same cochlea, the functional role of different pools of ANFs. The distribution of the characteristic frequencies of fibers shows a clear bimodal shape (with a first mode around 1.5 kHz and a second around 12 kHz) and a notch in the histogram near 3.5 kHz. Whereas the mean thresholds did not significantly differ in the two frequency regions, the shape of the rate-intensity functions does vary significantly with the fiber characteristic frequency. Above 3.5 kHz, the sound-driven rate is greater and the slope of the rate-intensity function is steeper. Interestingly, high-SR fibers show a very good synchronized onset response in quiet (small first-spike latency jitter) but a weak response under noisy conditions. The low-SR fibers exhibit the opposite behavior, with poor onset synchronization in quiet but a robust response in noise. Finally, the greater vulnerability of low-SR fibers to various injuries including noise- and age-related hearing loss is discussed with regard to patients with poor speech intelligibility in noisy environments. Together, these results emphasize the need to perform relevant clinical tests to probe the distribution of ANFs in humans, and develop appropriate techniques of rehabilitation. This article is part of a Special Issue entitled . PMID:27220483

  14. A Laboratory Exercise on Photoperiodic Changes in the Testes of the Mongolian Gerbil.

    ERIC Educational Resources Information Center

    Treagust, David F.; And Others

    1980-01-01

    A laboratory exercise using a gerbil is described for use in the high school biology class and in accordance with the National Science Teachers Association guidelines. The authors cite references that deal with current awareness of the moral status concerning animals. The exercise includes measurement and calculations. (SA)

  15. INACTIVATION OF GERBIL-CULTURED GIARDIA LAMBLIA CYSTS BY FREE CHLORINE

    EPA Science Inventory

    Giardia lamblia cysts were harvested from Mongolian gerbils and exposed to free chlorine in buffered water at pH 5, 7, and 9 at 15 degrees C. he contact times required to obtained a 2-log reduction in cyst survival (i.e., a 99% kill) were interpolated from survival curves generat...

  16. Biofortified Carrot Intake Enhances Liver Antioxidant Capacity and Vitamin A Status in Mongolian Gerbils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofortification efforts have increased concentrations of bioactive compounds in carrots. Vitamin A bioefficacy and antioxidant potential of four biofortified carrot varieties [purple/orange (PO), purple/orange/red (POR), orange/red (OR) and orange (O)] were measured in Mongolian gerbils (n = 73). ...

  17. Neurological deficits and brain edema after intracerebral hemorrhage in Mongolian gerbils.

    PubMed

    Kuroiwa, T; Okauchi, M; Hua, Y; Schallert, T; Keep, R F; Xi, G

    2008-01-01

    We examined the time course of neurological deficits in gerbils after an intracerebral hemorrhage (ICH) induced by autologous blood infusion and examined its correlation with the severity of perihematomal edema. Mongolian gerbils (n = 15) were subjected to stereotaxic autologous blood infusion (30 or 60 microL) into the left caudate nucleus. Corner-turn and forelimb-placing tests were performed before, and 1 and 3 days after ICH. Perihematomal water content was measured by tissue gravimetry. Gerbils developed neurological deficits and perihematomal edema at day 1 after ICH. Both neurological deficits and perihematomal edema were significantly greater in animals with 60 microL blood infusion compared to the 30 microL infusion group, and both neurological deficits and edema were also greater at 3 days compared to 1 day after ICH. The severity of neurological deficits paralleled the degree of perihematomal edema. We conclude that the Mongolian gerbil is a suitable model for studies on the behavioral effects of ICH. PMID:19066097

  18. The age-related quantitative ultrastructural changes in pinealocytes of gerbils.

    PubMed

    Swietoslawski, Jacek

    1999-01-01

    OBJECTIVES. Relatively few ultrastructural studies of the pineal gland of aging animals have been published. The pineal gland of the gerbil is especially interesting in respect to aging because of its progressive calcification with age, and this species has been considered as an excellent model for research on aging. Therefore, the aim of the present study was to examine the quantitative ultrastructure of pinealocytes of the gerbil in three different age groups. METHODS. Three groups of animals were included in the study: 1-month-old, 3-month-old, and 14-month-old. Cross-sectional areas of the pinealocyte and its nucleus and relative volumes of the following cell organelles: mitochondria, lysosomes, Golgi apparatus, granular endoplasmic reticulum and calcareous concretions as well as the number of dense-core vesicles and "synaptic" ribbons were analyzed. RESULTS. No age-dependent changes were observed in the size of pinealocytes and their nuclei. The relative volume of mitochondria and the number of dense-core vesicles increased progressively with age, and that of lysosomes was lowest in the 1-month-old animals and increased at age of 3 and 14 months, whereas a decrease in the relative volume of granular endoplasmic reticulum was observed in 3- and 14-month-old gerbils in comparison with 1-month-old animals. No difference was observed in relative volume of Golgi apparatus and in the number of "synaptic" ribbons. The most striking change was observed in the formation of calcareous concretion within the pineal with age. The pineal gland of 1-month-old gerbils was essentially devoid of these structures, their number and size in 3-month-old animals were moderate, and increased dramatically in 14-month-old animals. CONCLUSION. The ultrastructural features of the gerbil pinealocyte in all examined age groups point to high metabolic activity of these cells. PMID:11458204

  19. Antigen detection and apoptosis in Mongolian gerbil's kidney experimentally intraperitoneally infected by swine hepatitis E virus.

    PubMed

    Soomro, Majid Hussain; Shi, Ruihan; She, Ruiping; Yang, Yifei; Hu, Fengjiao; Li, Heng

    2016-02-01

    We examined the effect of hepatitis E virus (HEV) on the renal tissue pathogenesis, morphological damages and related molecular mechanisms following swine HEV suspension intraperitoneally inoculation in Mongolian gerbils. The microscopic and ultramicroscopic analyses of kidney tissue structure were carried out at different points after inoculation of HEV. The immunohistochemistry, real-time PCR and Western blot were performed to explore the molecular mechanisms associated with HEV presence in the renal tissues. Real-time PCR revealed that the copies of HEV RNA in the kidney were detected at 7 dpi, and peaked at 14 dpi at a concentration was 7.18 logs g(-1), with detection of HEV ORF2 antigen by immunohistochemistry. Hematoxylin and eosin (HE) staining showed pathological lesions including glomerular atrophy, degeneration, edema and necrosis of renal tubular epithelial cells and Mallory and Sirius red staining indicated the presence of collagen fibers and fibrosis in kidney tissues of inoculated gerbils. Ultrastructural studies of basal membrane of renal tubules demonstrated the rough and uneven with mitochondria swelling and vacuolation in the tissues of HEV inoculated animals. Similarly, significantly higher number of (TUNEL)-positive cells were seen in renal tubule tissues compared to control group. Moreover, immuno histochemical results indicated that significant increase expression of the B-cell lymphoma 2 (Bcl-2), Bcl-2 associated X protein (Bax), FAS and Caspase-3 in HEV inoculated Mongolian gerbils at each time points. Relative mRNA expression by real-time PCR revealed a significantly higher (P<0.05) mRNA level of BAX, Bcl-2 and caspase-3 transcription in HEV inoculated Mongolian gerbils. Our results demonstrates that activation of mitochondria and Caspase-3 protease might be induced the apoptosis which subsequently cause the necrosis and cell death of renal epithelial cells during acute phase of HEV infection in HEV inoculated Mongolian gerbils. PMID

  20. Therapeutic Effects of Policosanol and Atorvastatin against Global Brain Ischaemia-Reperfusion Injury in Gerbils

    PubMed Central

    Molina, V.; Ravelo, Y.; Noa, M.; Mas, R.; Pérez, Y.; Oyarzábal, A.; Mendoza, N.; Valle, M.; Jiménez, S.; Sánchez, J.

    2013-01-01

    Stroke is the third cause of death and the first of permanent adult disability. Pretreatment with policosanol and atorvastatin has been effective in experimental models of cerebral ischaemia in rodents. The objective was to compare the therapeutic effects of policosanol and atorvastatin in a model of global cerebral ischaemia in gerbils. Gerbils were distributed into seven groups, a negative control and six with ischaemia-reperfusion-induced global cerebral ischemia (one vehicle positive control, two policosanol (100 and 200 mg/kg), two atorvastatin (10 and 20 mg/kg) and one aspirin (60 mg/kg) group). Treatments were given 4 h after ischaemia induction. Effects on ischemia-reperfusion-induced symptoms, hyperlocomotion, damage of pyramidal hipoccampal neurons and increased plasma oxidative markers were investigated. Positive, not negative controls, exhibited clinical symptoms, hyperlocomotion, neuronal damage and increased plasma oxidative markers. Policosanol (100 and 200 mg/kg) reduced significantly ischemia-reperfusion-induced symptoms, the frequency of symptomatic animals, histological scores of neuronal damage and plasma oxidative markers as compared with the positive control group. Atorvastatin (10 and 20 mg/kg) decreased significantly the symptoms and histological scores, but unchanged the frequency of symptomatic gerbils and oxidative variables. Only the highest dose of policosanol (200 mg/kg) and atorvastatin (20 mg/kg) reduced significantly ischemia reperfusion-induced hyperlocomotion, policosanol being the most effective. Aspirin 60 mg/kg lowered significantly symptom score, the rate of symptomatic gerbils and hyperlocomotion versus the positive controls, but failed to modify oxidative parameters. In conclusion, postreperfusion treatment with policosanol and atorvastatin was effective for ameliorating symptoms, hyperlocomotion and neurological damage of hippocampal CA1 neurons in gerbils with ischemia-reperfusion-induced global cerebral ischemia, but only

  1. Spectral Sensitivity Measured with Electroretinogram Using a Constant Response Method

    PubMed Central

    Rocha, Fernando Allan de Farias; Gomes, Bruno Duarte; Silveira, Luiz Carlos de Lima; Martins, Sonia Limara; Aguiar, Renata Genaro; de Souza, John Manuel; Ventura, Dora Fix

    2016-01-01

    A new method is presented to determine the retinal spectral sensitivity function S(λ) using the electroretinogram (ERG). S(λ)s were assessed in three different species of myomorph rodents, Gerbils (Meriones unguiculatus), Wistar rats (Ratus norvegicus), and mice (Mus musculus). The method, called AC Constant Method, is based on a computerized automatic feedback system that adjusts light intensity to maintain a constant-response amplitude to a flickering stimulus throughout the spectrum, as it is scanned from 300 to 700 nm, and back. The results are presented as the reciprocal of the intensity at each wavelength required to maintain a constant peak to peak response amplitude. The resulting S(λ) had two peaks in all three rodent species, corresponding to ultraviolet and M cones, respectively: 359 nm and 511 nm for mice, 362 nm and 493 nm for gerbils, and 362 nm and 502 nm for rats. Results for mouse and gerbil were similar to literature reports of S(λ) functions obtained with other methods, confirming that the ERG associated to the AC Constant-Response Method was effective to obtain reliable S(λ) functions. In addition, due to its fast data collection time, the AC Constant Response Method has the advantage of keeping the eye in a constant light adapted state. PMID:26800521

  2. Spectral Sensitivity Measured with Electroretinogram Using a Constant Response Method.

    PubMed

    Rocha, Fernando Allan de Farias; Gomes, Bruno Duarte; Silveira, Luiz Carlos de Lima; Martins, Sonia Limara; Aguiar, Renata Genaro; de Souza, John Manuel; Ventura, Dora Fix

    2016-01-01

    A new method is presented to determine the retinal spectral sensitivity function S(λ) using the electroretinogram (ERG). S(λ)s were assessed in three different species of myomorph rodents, Gerbils (Meriones unguiculatus), Wistar rats (Ratus norvegicus), and mice (Mus musculus). The method, called AC Constant Method, is based on a computerized automatic feedback system that adjusts light intensity to maintain a constant-response amplitude to a flickering stimulus throughout the spectrum, as it is scanned from 300 to 700 nm, and back. The results are presented as the reciprocal of the intensity at each wavelength required to maintain a constant peak to peak response amplitude. The resulting S(λ) had two peaks in all three rodent species, corresponding to ultraviolet and M cones, respectively: 359 nm and 511 nm for mice, 362 nm and 493 nm for gerbils, and 362 nm and 502 nm for rats. Results for mouse and gerbil were similar to literature reports of S(λ) functions obtained with other methods, confirming that the ERG associated to the AC Constant-Response Method was effective to obtain reliable S(λ) functions. In addition, due to its fast data collection time, the AC Constant Response Method has the advantage of keeping the eye in a constant light adapted state. PMID:26800521

  3. The Fiber Contractility and Cytoskeleton Losses in Space are Less Pronounced in Mongolian Gerbils

    NASA Astrophysics Data System (ADS)

    Lipets, E. N.; Ponomareva, E. V.; Ogneva, I. V.; Vikhliantsev, I. M.; Karaduleva, E. V.; Kartashkina, N. L.; Kuznetsov, S. L.; Podlubnaia, Z. A.; Shenkman, B. S.

    2008-06-01

    This work was purposed on the comparison of space flight effects on m. soleus and m. tibialis anterior of Mongolian gerbils. The animals have been flown onboard biosatellite Foton-M3 for 12 days. Contractile properties of single skinned muscle fibers were studied. It was revealed that diameter of m. soleus skinned fibers and maximal isometric tension were decreased by 19.7% and 21.8% respectively. The Ca-sensitivity reduction wasn't significant, that was in accordance with absence of changes of titin and nebulin relative content in soleus and minor manifestations in slow-to-fast fiber ratio (9%, p<0.05). There weren't observed significant changes of the same parameters in m. tibialis anterior. Ultimately the fiber contractility and cytoskeleton losses in space are less pronounced in Mongolian gerbils than in rats.

  4. Prevention of Helicobacter pylori-induced gastric cancers in gerbils by a DNA demethylating agent.

    PubMed

    Niwa, Tohru; Toyoda, Takeshi; Tsukamoto, Tetsuya; Mori, Akiko; Tatematsu, Masae; Ushijima, Toshikazu

    2013-04-01

    Suppression of aberrant DNA methylation is a novel approach to cancer prevention, but, so far, the efficacy of the strategy has not been evaluated in cancers associated with chronic inflammation. Gastric cancers induced by Helicobacter pylori infection are known to involve aberrant DNA methylation and associated with severe chronic inflammation in their early stages. Here, we aimed to clarify whether suppression of aberrant DNA methylation can prevent H. pylori-induced gastric cancers using a Mongolian gerbil model. Administration of a DNA demethylating agent, 5-aza-2'-deoxycytidine (5-aza-dC), to gerbils (0.125 mg/kg for 50-55 weeks) decreased the incidence of gastric cancers induced by H. pylori infection and N-methyl-N-nitrosourea (MNU) treatment from 55.2% to 23.3% (P < 0.05). In gastric epithelial cells, DNA methylation levels of six CpG islands (HE6, HG2, SB1, SB5, SF12, and SH6) decreased to 46% to 68% (P < 0.05) of gerbils without 5-aza-dC treatment. Also, the global DNA methylation level decreased from 83.0% ± 4.5% to 80.3% ± 4.4% (mean ± SD) by 5-aza-dC treatment (P < 0.05). By 5-aza-dC treatment, Il1b and Nos2 were downregulated (42% and 58% of gerbils without, respectively) but Tnf was upregulated (187%), suggesting that 5-aza-dC treatment induced dysregulation of inflammatory responses. No obvious adverse effect of 5-aza-dC treatment was observed, besides testicular atrophy. These results showed that 5-aza-dC treatment can prevent H. pylori-induced gastric cancers and suggested that removal of induced DNA methylation and/or suppression of DNA methylation induction can become a target for prevention of chronic inflammation-associated cancers. PMID:23559452

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

    NASA Technical Reports Server (NTRS)

    Musacchia, X. J.

    1973-01-01

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

  6. Effects of Siblings on Reproductive Maturation and Infanticidal Behavior in Cooperatively Breeding Mongolian Gerbils

    PubMed Central

    Saltzman, Wendy; Thinda, Sumeer; Higgins, Alexis L.; Matsumoto, Wesley R.; Ahmed, Shahen; McGeehan, Laura; Kolb, Erik M.

    2008-01-01

    Mongolian gerbils living with their natal families undergo delayed reproductive maturation while helping to rear their younger siblings, whereas those housed away from their natal families may mature earlier but often respond aggressively to unfamiliar pups. We tested whether cohabitation with pups contributes to reproductive suppression and inhibition of infanticidal behavior, using young males and females housed with (1) their parents and younger siblings (pups), (2) parents without pups, (3) mixed-sex littermate groups, or (4) mixed-sex groups of unrelated peers. Maturation in males was inhibited by cohabitation with the parents, while maturation in females was further suppressed in the presence of pups. Males in all housing conditions showed little aggression towards unfamiliar pups, whereas females were usually infanticidal unless housed with pups. Aggression toward pups was especially pronounced in females that were pregnant or undergoing ovulatory cycles. Thus, cohabitation with younger siblings may intensify reproductive suppression and inhibit infanticidal behavior in female gerbils, whereas male gerbils exhibit parentally-induced reproductive suppression and low rates of infanticide even in the absence of younger siblings. PMID:18942052

  7. Tracking Chromosome Evolution in Southern African Gerbils Using Flow-Sorted Chromosome Paints

    PubMed Central

    Knight, L.I.; Ng, B.L.; Cheng, W.; Fu, B.; Yang, F.; Rambau, R.V.

    2013-01-01

    Desmodillus and Gerbilliscus (formerly Tatera) comprise a monophyletic group of gerbils (subfamily Gerbillinae) which last shared an ancestor approximately 8 million years ago; diploid chromosome number variation among the species ranges from 2n = 36 to 2n = 50. In an attempt to shed more light on chromosome evolution and speciation in these rodents, we compared the karyotypes of 7 species, representing 3 genera, based on homology data revealed by chromosome painting with probes derived from flow-sorted chromosomes of the hairy footed gerbil, Gerbillurus paeba (2n = 36). The fluorescent in situ hybridization data revealed remarkable genome conservation: these species share a high proportion of conserved chromosomes, and differences are due to 10 Robertsonian (Rb) rearrangements (3 autapomorphies, 3 synapomorphies and 4 hemiplasies/homoplasies). Our data suggest that chromosome evolution in Desmodillus occurred at a rate of ∼1.25 rearrangements per million years (Myr), and that the rate among Gerbilliscus over a time period spanning 8 Myr is also ∼1.25 rearrangements/Myr. The recently diverged Gerbillurus (G. tytonis and G. paeba) share an identical karyotype, while Gerbilliscus kempi, G. afra and G. leucogaster differ by 6 Rb rearrangements (a rate of ∼1 rearrangement/Myr). Thus, our data suggests a very slow rate of chromosomal evolution in Southern African gerbils. PMID:23652816

  8. Regional blood flows measured in Mongolian gerbil by a modified microsphere method.

    PubMed

    Matsumoto, M; Kimura, K; Fujisawa, A; Matsuyama, T; Asai, T; Uyama, O; Yoneda, S; Abe, H

    1982-06-01

    Regional blood flow to major organs and regional cerebral blood flow were determined in seven anesthetized male gerbils by a modified microsphere method. Carbonized microspheres, 15 micrometers in diameter and labeled with 85Sr or 141Ce, were injected into the left ventricle by cardiac puncture through the closed thorax, and reference samples of known volume were withdrawn from tail-artery cannula. No significant hemodynamic alterations were observed during microsphere administration, and extraction of 15-micrometers microspheres by the pulmonary or systemic capillary beds was nearly 100%. The adequacy of mixing of microspheres in the left ventricle was also validated. The absolute regional blood flow to various organs and regional cerebral blood flow were expressed in terms of milliliters per minute per gram tissue weight, and the values mostly agreed with those reported previously in rats. The results indicate that the reference sample method can be applied to the gerbil. This method should allow the gerbil, which is an animal widely used in stroke research, to be conveniently used for hemodynamic studies when organ blood flow and regional cerebral blood flow are necessary. PMID:7091359

  9. Tracking chromosome evolution in southern African gerbils using flow-sorted chromosome paints.

    PubMed

    Knight, L I; Ng, B L; Cheng, W; Fu, B; Yang, F; Rambau, R V

    2013-01-01

    Desmodillus and Gerbilliscus (formerly Tatera) comprise a monophyletic group of gerbils (subfamily Gerbillinae) which last shared an ancestor approximately 8 million years ago; diploid chromosome number variation among the species ranges from 2n = 36 to 2n = 50. In an attempt to shed more light on chromosome evolution and speciation in these rodents, we compared the karyotypes of 7 species, representing 3 genera, based on homology data revealed by chromosome painting with probes derived from flow-sorted chromosomes of the hairy footed gerbil, Gerbillurus paeba (2n = 36). The fluorescent in situ hybridization data revealed remarkable genome conservation: these species share a high proportion of conserved chromosomes, and differences are due to 10 Robertsonian (Rb) rearrangements (3 autapomorphies, 3 synapomorphies and 4 hemiplasies/homoplasies). Our data suggest that chromosome evolution in Desmodillus occurred at a rate of ~1.25 rearrangements per million years (Myr), and that the rate among Gerbilliscus over a time period spanning 8 Myr is also ~1.25 rearrangements/Myr. The recently diverged Gerbillurus (G. tytonis and G. paeba) share an identical karyotype, while Gerbilliscus kempi, G. afra and G. leucogaster differ by 6 Rb rearrangements (a rate of ~1 rearrangement/Myr). Thus, our data suggests a very slow rate of chromosomal evolution in Southern African gerbils. PMID:23652816

  10. Babesia divergens infections in the Mongolian gerbil: characteristics of a human strain.

    PubMed

    Liddell, K G; Lucas, S B; Williams, H

    1981-04-01

    A strain of the cattle piroplasm Babesia divergens isolated from a fatal human infection was propagated in the Mongolian gerbil through 150 semi-continuous intraperitoneal passages. The infection was normally fatal; death, accompanied by profuse haemoglobinuria and debilitation, occurred as early as 44 h after intraperitoneal inoculation of heavily parasitized blood with precipitous drops in red blood cell and platelet counts. The average maximum parasitaemia achieved increased on continuous passage reaching 80% by the 150th stage. Twenty-four hours after infection erythrophagocytosis and splenic congestion were apparent by light and electron-microscopical examination and by 48 h hepatic necrosis, renal tubular damage with haemoglobin cast accumulation and ischaemic necrosis of ileal mucosa had developed. Gerbils were highly susceptible to small numbers of parasites when the inoculum was either fresh parasitized blood in high dilution or erythrocytes concentrated from animals showing minimal parasitaemia. Animals inoculated with parasites preserved in dimethyl sulphoxide at low temperatures usually developed fatal infections. However, occasionally animals suffered at most a low grade parasitaemia subsequent to recovery with parasite elimination. These animals were immune to further challenge, and no chronic infections developed. A field strain of B. divergens isolated locally from a case of bovine redwater behaved similarly to the human strain on continuous passage in gerbils. PMID:7220085

  11. Modulation of ischemic-induced damage to cerebral adenylate cyclase in gerbils by calcium channel blockers.

    PubMed

    Christie-Pope, B C; Palmer, G C

    1986-12-01

    It has been previously established that prolonged bilateral carotid occlusion followed by recirculation produces damage to the synaptic enzyme adenylate cyclase in the frontal cortex of the gerbil. Since calcium entrance into the brain may account in part for the deleterious consequences of stroke, the present study examined whether pretreatment with calcium channel blockers would modify the effects of 60 min of bilateral ischemia plus 40 min of reflow on various parameters of cortical adenylate cyclase activation. In this context activation of cerebral homogenates by norepinephrine with or without 5'-guanylyl imidodiphosphate was preserved by pretreatment of ischemic gerbils with verapamil but worsened by flunarizine. In contrast, in particulate fractions (treated with EGTA to reduce metallic ion levels) the damage to the Mn2+-sensitive catalytic site of adenylate cyclase was prevented only by flunarizine. Pretreatment with the two calcium channel blockers resulted in an elevated basal activity of the enzyme, thereby reducing the response in the homogenate preparation to forskolin. Gerbils pretreated with verapamil tended to have an increased ability for survival resulting from the ischemic episode. Under in vitro conditions the enzyme preparations were not markedly influenced by either drug. PMID:3508245

  12. Experimental peritonitis induced by oral administration of indomethacin in Mongolian gerbils

    PubMed Central

    Lee, Jin-Uk

    2006-01-01

    The possibility of inducing peritoneal inflammation in three murine species (gerbils, rats and mice) via the oral administration of indomethacin was investigated with the overall aim of developing an experimental animal model for human peritonitis. Gerbils given high doses of indomethacin at a rate of 30 mg and 40 mg/kg body weight showed swelling of the abdomen, depression and dyspnea within 4 days after the treatment. The severity of the clinical symptoms increased with time. The animals were confirmed as having developed peritonitis based on the pathological features including inflammation of the peritoneum, and fibrinous adhesion of the abdominal organs in the abdominal cavity. The severity of peritonitis increased with increasing dose of indomethacin, and was not related to the gender of the animal. On the other hand, peritoneal inflammation did not develop in the rats and mice even at high doses. Therefore, the administration of 30 mg/kg body weight of indomethacin is an effective and simple method of inducing peritonitis in 5-week-old Mongolian gerbils. The animal peritonitis model used in this study can be used as an effective tool for examining potential therapeutic compounds for preventing peritoneal damage during peritonitis, and provide insight into the pathophysiology of peritonitis. PMID:16645338

  13. Regional cerebral palmitate incorporation following transient bilateral carotid occlusion in awake gerbils

    SciTech Connect

    Tone, O.; Miller, J.C.; Bell, J.M.; Rapoport, S.I.

    1987-11-01

    (/sup 14/C)Palmitate was injected intravenously in awake gerbils at various times after 5 minutes of bilateral carotid artery occlusion or a sham operation. Regional rates of incorporation of plasma palmitate into the hippocampus and other regions of the anterior circulation were determined relative to the mean rate of incorporation into regions of the posterior circulation using quantitative autoradiography and a ratio method of analysis. One day after bilateral carotid occlusion, relative palmitate incorporation was elevated significantly by 16% in the CA4 pyramidal cell layer and by 20% in the dentate gyrus of the hippocampus compared with sham-operated gerbils. At 3 days, significant elevations of this magnitude were found in the CA3 and CA4 cell layers, whereas relative incorporation was reduced by 26% in the CA1 pyramidal cell layer. At 7 days, the only significant difference from control was a 15% elevated incorporation in the CA3 pyramidal cell layer. Histologic examination indicated substantial cell death in the CA1 pyramidal layer at 3 days, with extensive glial reaction and phagocytic invasion at 7 days. Our results suggest that the turnover of palmitate-containing lipids is reduced in the CA1 layer of the gerbil hippocampus but that lipid synthesis is stimulated in hippocampal regions (CA3, CA4, dentate gyrus) affected by but recovering from transient bilateral carotid occlusion.

  14. Selection of an effective microsatellite marker system for genetic control and analysis of gerbil populations in China.

    PubMed

    Du, X Y; Li, W; Sa, X Y; Li, C L; Lu, J; Wang, Y Z; Chen, Z W

    2015-01-01

    Although gerbils have been widely used in many areas of biological research over many years, there is currently no effective genetic quality control system available. In the present study, we sought to establish a microsatellite marker system for quality control and conducted an optimized analysis of 137 microsatellite loci in two laboratory gerbil populations and one wild population. Independent sample t-tests on the mean effective allele number, mean of Shannon's information index, and mean HE suggested that 28 of the 137 microsatellite markers were informative for gerbil genetic control. Analysis of 4 laboratory gerbil populations and 1 wild population using the 28 microsatellite loci indicated that allele numbers varied from 1.9639 (Guangzhou, GZ) to 6.6071 (North-West wild, NW). The average of HO versus HE was 0.6236/0.3802, 0.6671/0.4159, 0.4185/0.3464, 0.4592/0.3821, and 0.3972/0.4167 for the Beijing, NW, Hangzhou, Dalian, and GZ populations, respectively. The GZ population showed the greatest differentiation, having higher RST and Nei's standard genetic distances. An AMO-VA revealed high genetic differentiation among the five populations (FST = 0.296). The microsatellite system established here is effective and will be important in future studies for genetic quality control and monitoring of gerbil breeds. PMID:26400333

  15. Meggittina numida n. sp. (Cyclophyllidea: Catenotaeniidae), a parasite of the Shaw's jird Meriones shawi (Duvernoy) (Rodentia: Gerbillinae) in Tunisia.

    PubMed

    Jrijer, Jamel; Neifar, Lassad

    2014-06-01

    Meggittina numida n. sp. (Cyclophyllidea: Catenotaeniidae: Skrjabinotaeniinae) is described from the small intestine of the Shaw's jird Meriones shawi (Duvernoy) (Rodentia, Muridae, Gerbillinae) trapped in central Tunisia. The new species can be distinguished from the four other members of Meggittina Lynsdale, 1953 by the high number of proglottids (8-25 vs max. 6) and by the elongated strobila (8.2-60 mm in length vs max. 5.6 mm). M numida n. sp. further differs from M. cricetomydis (Hockley, 1961) in the direction of gravid proglottids; from M. baeri Lynsdale, 1953 in having narrower and much longer strobila; from M. aegyptiaca (Wolfgang, 1956) in the greater number of testes and the larger cirrus-sac; and from M. gerbilli in the position of the genital pore. The diagnosis of Meggittina is amended in order to include the most specific features of M. numida n. sp. as follows: strobila consisting of a small scolex, wide neck and one to twenty-five proglottids. This is the first species of Meggittina described from Tunisia. The taxonomic relationships of Meggittina spp. are discussed in the light of the description of the new species. PMID:24832187

  16. Excystation and culturing of human and animal Giardia spp. by using gerbils and TYI-S-33 medium.

    PubMed Central

    Wallis, P M; Wallis, H M

    1986-01-01

    Mongolian gerbils were used as an animal model to excyst and host Giardia spp. isolated from meadow voles, dogs, beavers, and humans. Both cysts and trophozoites were used to establish infections. Gerbils were infected with Giardia duodenalis from beaver, dog, and human sources, and the trophozoites were extracted and cultured in Diamond TYI-S-33 medium. The use of gentamicin and ampicillin in the medium, coupled with treatment of gerbils with gentamicin before they were sacrificed, permitted the elimination of trophozoite purification techniques before culturing. An extract of whole bovine calf blood, CLEX, was substituted for fetal bovine serum in TYI-S-33 medium and was found to be both adequate and less expensive. PMID:3516070

  17. Dose Response of Listeria monocytogenes Invasion, Fetal Morbidity, and Fetal Mortality after Oral Challenge in Pregnant and Nonpregnant Mongolian Gerbils

    PubMed Central

    Roulo, Rebecca M.; Fishburn, Jillian D.; Amosu, Mayowa; Etchison, Ashley R.

    2014-01-01

    Listeria monocytogenes is a food-borne pathogen that can result in adverse pregnancy outcomes, such as stillbirth or premature delivery. The Mongolian gerbil was recently proposed as the most appropriate small-animal model of listeriosis due to its susceptibility to the same invasion pathways as humans. The objectives of this study were to investigate invasion and adverse pregnancy outcomes in gerbils orally exposed to L. monocytogenes, to compare the dose-response data to those of other animal models, and to investigate differences in the responses of pregnant versus nonpregnant gerbils. Gerbils were orally exposed to 0 (control), 103, 105, 107, or 109 CFU L. monocytogenes in whipping cream. L. monocytogenes was recovered in a dose-dependent manner from fecal samples, adult organs, and pregnancy-associated tissues. Dams exposed to 109 CFU had more invaded organs and higher concentrations of L. monocytogenes in almost all organs than nonpregnant animals, though no differences in fecal shedding were seen between the two groups. Adverse pregnancy outcomes occurred only in the dams treated with 109 CFU. A 50% infectivity dose (ID50) of 2.60 × 106 CFU for fetuses was calculated by fitting the data to a logistic model. Our results suggest that the 50% lethal dose (LD50) falls within the range of 5 × 106 to 5 × 108 CFU. This range includes the guinea pig and nonhuman primate LD50s, but the observation that L. monocytogenes-induced stillbirths can be seen in guinea pigs and primates exposed to lower doses than those at which stillbirths were seen in gerbils indicates that gerbils are not more sensitive to L. monocytogenes invasion. PMID:25156729

  18. Three-dimensional vibration of the malleus and incus in the living gerbil.

    PubMed

    Decraemer, W F; de La Rochefoucauld, O; Funnell, W R J; Olson, E S

    2014-08-01

    In previous studies, 3D motion of the middle-ear ossicles in cat and human was explored, but models for hearing research have shifted in the last few decades to smaller mammals, and gerbil, in particular, has become a popular hearing model. In the present study, we have measured with an optical interferometer the 3D motion of the malleus and incus in anesthetized gerbil for sound of moderate intensity (90-dB sound pressure level) over a broad frequency range. To access the ossicles, the pars flaccida was removed exposing the neck and head of the malleus and the incus from the malleus-incus joint to the plate of the lenticular process. Vibration measurements were done at six to eight points per ossicle while the angle of observation was varied over approximately 30 ° to enable calculation of the 3D rigid-body velocity components. These components were expressed in an intrinsic reference frame, with one axis along the anatomical suspension axis of the malleus-incus block and a second axis along the stapes piston direction. Another way of describing the motion that does not assume an a priori rotation axis is to calculate the instantaneous rotation axis (screw axis) of the malleus/incus motion. Only at frequencies below a few kilohertz did the screw axis have a maximum rotation in a direction close to that of the ligament axis. A slight slippage in the malleus-incus joint developed with increasing frequency. Our findings are useful in determining the sound transfer characteristics through the middle ear and serve as a reference for validation of mathematical middle-ear models. Last but not least, comparing our present results in gerbil with those of previously measured species (human and cat) exposes similarities and dissimilarities among them. PMID:24691793

  19. Myocardial Structural and Biological Anomalies Induced by High Fat Diet in Psammomys obesus Gerbils

    PubMed Central

    Sahraoui, Abdelhamid; Dewachter, Céline; de Medina, Geoffrey; Naeije, Robert

    2016-01-01

    Background Psammomys obesus gerbils are particularly prone to develop diabetes and obesity after brief period of abundant food intake. A hypercaloric high fat diet has been shown to affect cardiac function. Here, we sought to determine whether a short period of high fat feeding might alter myocardial structure and expression of calcium handling proteins in this particular strain of gerbils. Methods Twenty Psammomys obesus gerbils were randomly assigned to receive a normal plant diet (controls) or a high fat diet. At baseline and 16-week later, body weight, plasma biochemical parameters (including lipid and carbohydrate levels) were evaluated. Myocardial samples were collected for pathobiological evaluation. Results Sixteen-week high fat dieting resulted in body weight gain and hyperlipidemia, while levels of carbohydrates remained unchanged. At myocardial level, high fat diet induced structural disorganization, including cardiomyocyte hypertrophy, lipid accumulation, interstitial and perivascular fibrosis and increased number of infiltrating neutrophils. Myocardial expressions of pro-apoptotic Bax-to-Bcl-2 ratio, pro-inflammatory cytokines [interleukin (IL)-1β and tumor necrosis factor (TNF)-α], intercellular (ICAM1) and vascular adhesion molecules (VCAM1) increased, while gene encoding cardiac muscle protein, the alpha myosin heavy polypeptide (MYH6), was downregulated. Myocardial expressions of sarco(endo)plasmic calcium-ATPase (SERCA2) and voltage-dependent calcium channel (Cacna1c) decreased, while protein kinase A (PKA) and calcium-calmodulin-dependent protein kinase (CaMK2D) expressions increased. Myocardial expressions of ryanodine receptor, phospholamban and sodium/calcium exchanger (Slc8a1) did not change. Conclusions We conclude that a relative short period of high fat diet in Psammomys obesus results in severe alterations of cardiac structure, activation of inflammatory and apoptotic processes, and altered expression of calcium-cycling determinants

  20. Experimental study of vibrations of gerbil tympanic membrane with closed middle ear cavity.

    PubMed

    Maftoon, Nima; Funnell, W Robert J; Daniel, Sam J; Decraemer, Willem F

    2013-08-01

    The purpose of the present work is to investigate the spatial vibration pattern of the gerbil tympanic membrane (TM) as a function of frequency. In vivo vibration measurements were done at several locations on the pars flaccida and pars tensa, and along the manubrium, on surgically exposed gerbil TMs with closed middle ear cavities. A laser Doppler vibrometer was used to measure motions in response to audio frequency sine sweeps in the ear canal. Data are presented for two different pars flaccida conditions: naturally flat and retracted into the middle ear cavity. Resonance of the flat pars flaccida causes a minimum and a shallow maximum in the displacement magnitude of the manubrium and pars tensa at low frequencies. Compared with a flat pars flaccida, a retracted pars flaccida has much lower displacement magnitudes at low frequencies and does not affect the responses of the other points. All manubrial and pars tensa points show a broad resonance in the range of 1.6 to 2 kHz. Above this resonance, the displacement magnitudes of manubrial points, including the umbo, roll off with substantial irregularities. The manubrial points show an increasing displacement magnitude from the lateral process toward the umbo. Above 5 kHz, phase differences between points along the manubrium start to become more evident, which may indicate flexing of the tip of the manubrium or a change in the vibration mode of the malleus. At low frequencies, points on the posterior side of the pars tensa tend to show larger displacements than those on the anterior side. The simple low-frequency vibration pattern of the pars tensa becomes more complex at higher frequencies, with the breakup occurring at between 1.8 and 2.8 kHz. These observations will be important for the development and validation of middle ear finite-element models for the gerbil. PMID:23624883

  1. Characterization of progressive metaplasia in the gastric corpus mucosa of Mongolian gerbils infected with Helicobacter pylori.

    PubMed

    Shimizu, Takahiro; Choi, Eunyoung; Petersen, Christine P; Noto, Jennifer M; Romero-Gallo, Judith; Piazuelo, Maria B; Washington, M Kay; Peek, Richard M; Goldenring, James R

    2016-08-01

    Spasmolytic polypeptide-expressing metaplasia (SPEM) and intestinal metaplasia are considered neoplastic precursors of gastric adenocarcinoma in humans. Loss of parietal cells causes the development of SPEM in the gastric corpus and then chronic inflammation drives SPEM toward a more proliferative lineage. Mongolian gerbils infected with Helicobacter pylori develop chronic gastritis and metaplasia, mimicking aspects of human gastritis with H. pylori infection. We therefore examined metaplastic lineages in the gastric corpus mucosa of gerbils infected by H. pylori strain 7.13, which produces rapid onset of severe inflammation. Six weeks following H. pylori infection, Griffonia simplicifolia lectin II (GSII)-positive SPEM developed in the base of oxyntic glands in association with parietal cell loss and inflammation. In association with severe inflammation, SPEM glands evolved into aberrant phenotypes, including branched lesions, dilated lesions, and penetrating invasive glands. Mucin 4 (MUC4) was up-regulated in SPEM and progressive SPEM. Clusterin was expressed in the tips of branched and dilated lesions and throughout regions of invasive glands. Intriguingly, clusterin-positive regions in these lesions expressed Ki67 and matrix metalloproteinase 7 (MMP-7). These same regions were also positive for expression of phospho-IkBα, suggestive of activated NFkB signalling. These findings suggest that clusterin-positive regions in progressive phenotypes of SPEM have invasive characteristics. Thus, H. pylori infection in gerbils induces SPEM, which then can progress to further aberrant and invasive metaplastic phenotypes. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:27125972

  2. Direct evidence of acute, massive striatal dopamine release in gerbils with unilateral strokes.

    PubMed

    Brannan, T; Weinberger, J; Knott, P; Taff, I; Kaufmann, H; Togasaki, D; Nieves-Rosa, J; Maker, H

    1987-01-01

    Dopamine release into the extracellular space was measured with in vivo electrochemical detection in the ipsilateral and contralateral striata in Mongolian gerbils that suffered a stroke after acute unilateral carotid artery ligations. A sevenfold increase in the dopamine signal occurred within 15 minutes of carotid ligation in the ischemic side, while the unlesioned side had no significant change. Increased extracellular levels of dopamine persisted throughout the 3-hour recording period. Pretreatment with alpha-methyl-p-tyrosine 6 hours prior to recording significantly attenuated the signal increase. This study is the first direct demonstration of the marked, continuous dopamine release that occurs during acute cerebral ischemia. PMID:3810742

  3. Determining the Orthotropic Properties of Gerbil Basilar Membrane from Space Constant Measurements

    NASA Astrophysics Data System (ADS)

    Liu, Shuangqin; White, Robert

    2011-11-01

    A geometrically nonlinear composite orthotropic plate finite element model is developed to analyze two sets of experimental results in order to extract the two effective elastic moduli, the effective shear modulus and the effective Poisson's ratio for the gerbil cochlea partition. It is shown that the spatial decay rate (the space constant) for the in-plane deflection is different than for the out-of-plane deflection, which has a significant effect on the derived partition properties. Orthotropy ratios (the ratio of the two elastic moduli) are approximately 65 close to the base to 10 in the upper middle turn of the cochlea.

  4. Dimensional analysis and dynamic response characterization of mammalian peripheral vestibular structures.

    PubMed

    Ramprashad, F; Landolt, J P; Money, K E; Laufer, J

    1984-03-01

    Extensive morphometric measurements were made on the vestibular system of the rabbit ( Oryctulagus cuniculus), the gerbil (Meriones unguiculatus), the chinchilla (Chinchilla laniger ), and the squirrel monkey (Saimiri sciureus) from serial sections of temporal bones. Additionally, a more limited set of measurements were also completed on the owl monkey (Aotus trivirgatus), the Capuchin monkey (Cebus sp.), the harp seal ( Pagophilus groenlandicus Erxleben , 1777), and the two-toed sloth ( Choloepus sp.). The following measurements were made: 1) radius of curvature (R) of each membranous semicircular canal (herein called semicircular duct-see nomenclature in Nomina Anatomica (1968) ), 2) cross-sectional diameter of the ducts and the osseous semicircular canals, and 3) some pertinent morphometrics of the cristae ampullares and the utricle. In all species studied 1) the radii of curvature of the three semicircular ducts are dissimilar, with that of the lateral duct being as small as, or smaller than, those of the anterior and posterior ducts; 2) R for the anterior duct is largest in the harp seal and the rabbit; 3) the canal and duct dimensions are largest in the Capuchin and squirrel monkeys, the two-toed sloth, and the harp seal, and smallest in the gerbil; 4) the proportion of otic fluid "space" that is occupied by endolymph shows a ranking of gerbil greater than rabbit greater than two-toed sloth greater than chinchilla = owl monkey greater than squirrel monkey greater than Capuchin monkey greater than harp seal; and 5) the gross ampullary and utricular dimensions are largest in the harp seal and smallest in the gerbil. These measurements were used for determining the time constants describing semicircular-canal dynamics in the Steinhausen (1931, 1933) and Oman -Marcus (1980) equations. PMID:6609629

  5. Impact of heavy metal pollution on the hemogram and serum biochemistry of the Libyan jird, Meriones libycus.

    PubMed

    Adham, Khadiga G; Al-Eisa, Nadia A; Farhood, Manal H

    2011-09-01

    The stress profiles of the hemogram and serum biochemistry were determined in the context of heavy metal (Cd, Cu, Hg, Ni and Pb) exposure in the wild libyan jird, Meriones libycus, from one of Riyadh's polluted areas versus a reference site. Coupling the pronounced drop in platelets (PLT) (28%) and mean platelet volume (MPV) (17%) with the insignificant responses of other red blood cell indices, suggests bone marrow suppression that is characterized by thrombocytopenia as an initial abnormality. The species-specific stress leukogram for M. libycus is expressed by leukocytosis (66%), monocytosis (40%), lymphocytosis (23%) with eosinopenia (81%) and neutropenia (42%). Hyperglycemia (50%), hyper-low-density-lipoproteinemia (38%), hypocortisolism (85%) and hypotriglyceridemia (55%) depicted serum biochemistry profile. In polluted jirds, the elevated activities of pseudocholinesterase (PChE) and serum marker enzymes (alanine aminotransferase ALT, aspartate aminotransferase AST and creatine kinase CK) strongly suggest functional damage of the liver and/or heart. A potential role of PChE in low-density lipoprotein (LDL) metabolism is implied in the joint rise of both indices and in the recognized relationship between PChE and lipid metabolites. While increased utilization in lipid metabolism and energy synthesis could rationalize the inhibition of the normal patterns of triglycerides and lactate dehydrogenase (LDH), the inhibited activities of LDH could additionally be attributed to its hormetic behavior towards low and high metal concentrations. The overall findings presented here documented the relevance of M. libycus in biomonitoring and predicting the risk imposed on human populations living in polluted areas. PMID:21601906

  6. Risk assessment of heavy metal contamination in soil and wild Libyan jird Meriones libycus in Riyadh, Saudi Arabia.

    PubMed

    Adham, Khadiga G; Al-Eisa, Nadia A; Farhood, Manal H

    2011-11-01

    This study was undertaken to document the impact of heavy metal pollution on the Libyan jird, Meriones libycus and to contribute to an environmental impact statement for the rapidly growing City of Riyadh. All metal concentrations in surface soil of a polluted site (within Riyadh City) were higherthan those from a reference site (outside the city).Although Pb declined versus earlier reports on Riyadh soil, Cd (0.97 microg g(-1)) and Hg (0.28 microg g(-1)) were above some of the most stringent quality guidelines (0.07-0.62 microg g(-1) for Cd and 0.14-0.18 microg g(-1) for Hg). Metal distribution in M. libycus proved site-related and organ-specific, recognizing a higher affinity of most tested metals towards the kidneys, liver and brain than the lung and heart. The comparatively lower site-specific accumulation of Pb in soft tissues was attributed primarily to its major hypothetical accumulation in bones, whereas, the transition rate of Hg from the liver was suggested to be lower to the brain than to the kidneys. Although a non hazardous status was assumed for Cu (11.27-13.16 microg g(-1)) and Hg (up to 0.207 microg g(-1)) in tissues of M. libycus, a potential risk was imposed by mean tissue concentrations of Cd (up to 3.29 microg g(01)), Ni (up to 1.48 microg g(-1)) and Pb (up to 1.94 microg g(-1)). On the grounds of the significantly higher metal levels in polluted soft tissues versus reference subjects, Libyan jirds possess high exposure potential and can be useful biomonitors of environmental metal contamination. PMID:22471221

  7. Structure and function of the mammalian middle ear. II: Inferring function from structure.

    PubMed

    Mason, Matthew J

    2016-02-01

    Anatomists and zoologists who study middle ear morphology are often interested to know what the structure of an ear can reveal about the auditory acuity and hearing range of the animal in question. This paper represents an introduction to middle ear function targetted towards biological scientists with little experience in the field of auditory acoustics. Simple models of impedance matching are first described, based on the familiar concepts of the area and lever ratios of the middle ear. However, using the Mongolian gerbil Meriones unguiculatus as a test case, it is shown that the predictions made by such 'ideal transformer' models are generally not consistent with measurements derived from recent experimental studies. Electrical analogue models represent a better way to understand some of the complex, frequency-dependent responses of the middle ear: these have been used to model the effects of middle ear subcavities, and the possible function of the auditory ossicles as a transmission line. The concepts behind such models are explained here, again aimed at those with little background knowledge. Functional inferences based on middle ear anatomy are more likely to be valid at low frequencies. Acoustic impedance at low frequencies is dominated by compliance; expanded middle ear cavities, found in small desert mammals including gerbils, jerboas and the sengi Macroscelides, are expected to improve low-frequency sound transmission, as long as the ossicular system is not too stiff. PMID:26100915

  8. Anthelmintic activity of Cymbopogon citratus against Haemonchus contortus.

    PubMed

    Macedo, Iara Tersia Freitas; Oliveira, Lorena Mayana Beserra de; Ribeiro, Wesley Lyeverton Correia; Santos, Jessica Maria Leite dos; Silva, Kaline das Chagas; Araújo Filho, José Vilemar de; Camurça-Vasconcelos, Ana Lourdes Fernandes; Bevilaqua, Claudia Maria Leal

    2015-01-01

    Parasitic nematodes are of major economic importance in livestock. An alternative for the control of parasites is phytotherapy. This study evaluated the efficacy of Cymbopogon citratus decoction (CcD), C. citratus essential oil (CcEo) and citral against Haemonchus contortus using in vitro egg hatch test (EHT) and larval development test (LDT) and an in vivo test using a Meriones unguiculatus (gerbil) model. The effect of 800 mg/kg CcEo was evaluated in gerbils that had been artificially infected with 5,000 third-stage H. contortus larvae. The effective concentrations required to inhibit 50% (EC50) of egg hatching were 0.46, 0.14 and 0.13 mg/mL for CcD, CcEo and citral, respectively. The EC50 values in the LDT were 5.04, 1.92 and 1.37 mg/mL for CcD, CcEo and citral, respectively. H. contortus population in the group treated with C. citratus essential oil was reduced by 38.5% (P< 0.05) in comparison to the control group. These results suggest that it may be possible to use C. citratus essential oil to control of H. contortus parasite of small ruminant. PMID:26444058

  9. Moonlight avoidance in gerbils reveals a sophisticated interplay among time allocation, vigilance and state-dependent foraging.

    PubMed

    Kotler, Burt P; Brown, Joel; Mukherjee, Shomen; Berger-Tal, Oded; Bouskila, Amos

    2010-05-22

    Foraging animals have several tools for managing the risk of predation, and the foraging games between them and their predators. Among these, time allocation is foremost, followed by vigilance and apprehension. Together, their use influences a forager's time allocation and giving-up density (GUD) in depletable resource patches. We examined Allenby's gerbils (Gerbilus andersoni allenbyi) exploiting seed resource patches in a large vivarium under varying moon phases in the presence of a red fox (Vulpes vulpes). We measured time allocated to foraging patches electronically and GUDs from seeds left behind in resource patches. From these, we estimated handling times, attack rates and quitting harvest rates (QHRs). Gerbils displayed greater vigilance (lower attack rates) at brighter moon phases (full < wane < wax < new). Similarly, they displayed higher GUDs at brighter moon phases (wax > full > new > wane). Finally, gerbils displayed higher QHRs at new and waxing moon phases. Differences across moon phases not only reflect changing time allocation and vigilance, but changes in the state of the foragers and their marginal value of energy. Early in the lunar cycle, gerbils rely on vigilance and sacrifice state to avoid risk; later they defend state at the cost of increased time allocation; finally their state can recover as safe opportunities expand. In the predator-prey foraging game, foxes may contribute to these patterns of behaviours by modulating their own activity in response to the opportunities presented in each moon phase. PMID:20053649

  10. What do predators really want? The role of gerbil energetic state in determining prey choice by Barn Owls.

    PubMed

    Embar, Keren; Mukherjee, Shomen; Kotler, Burt P

    2014-02-01

    In predator-prey foraging games, predators should respond to variations in prey state. The value of energy for the prey changes depending on season. Prey in a low energetic state and/or in a reproductive state should invest more in foraging and tolerate higher predation risk. This should make the prey more catchable, and thereby, more preferable to predators. We ask, can predators respond to prey state? How does season and state affect the foraging game from the predator's perspective? By letting owls choose between gerbils whose states we experimentally manipulated, we could demonstrate predator sensitivity to prey state and predator selectivity that otherwise may be obscured by the foraging game. During spring, owls invested more time and attacks in the patch with well-fed gerbils. During summer, owls attacked both patches equally, yet allocated more time to the patch with hungry gerbils. Energetic state per se does not seem to be the basis of owl choice. The owls strongly responded to these subtle differences. In summer, gerbils managed their behavior primarily for survival, and the owls equalized capture opportunities by attacking both patches equally. PMID:24669722

  11. Alarm signals of the great gerbil: Acoustic variation by predator context, sex, age, individual, and family group

    NASA Astrophysics Data System (ADS)

    Randall, Jan A.; McCowan, Brenda; Collins, Kellie C.; Hooper, Stacie L.; Rogovin, Konstantin

    2005-10-01

    The great gerbil, Rhombomys opinus, is a highly social rodent that usually lives in family groups consisting of related females, their offspring, and an adult male. The gerbils emit alarm vocalizations in the presence of diverse predators with different hunting tactics. Alarm calls were recorded in response to three predators, a monitor lizard, hunting dog, and human, to determine whether the most common call type, the rhythmic call, is functionally referential with regard to type of predator. Results show variation in the alarm calls of both adults and subadults with the type of predator. Discriminant function analysis classified an average of 70% of calls to predator type. Call variation, however, was not limited to the predator context, because signal structure also differed by sex, age, individual callers, and family groups. These variations illustrate the flexibility of the rhythmic alarm call of the great gerbil and how it might have multiple functions and communicate in multiple contexts. Three alarm calls, variation in the rhythmic call, and vibrational signals generated from foot-drumming provide the gerbils with a varied and multi-channel acoustic repertoire.

  12. Moonlight avoidance in gerbils reveals a sophisticated interplay among time allocation, vigilance and state-dependent foraging

    PubMed Central

    Kotler, Burt P.; Brown, Joel; Mukherjee, Shomen; Berger-Tal, Oded; Bouskila, Amos

    2010-01-01

    Foraging animals have several tools for managing the risk of predation, and the foraging games between them and their predators. Among these, time allocation is foremost, followed by vigilance and apprehension. Together, their use influences a forager's time allocation and giving-up density (GUD) in depletable resource patches. We examined Allenby's gerbils (Gerbilus andersoni allenbyi) exploiting seed resource patches in a large vivarium under varying moon phases in the presence of a red fox (Vulpes vulpes). We measured time allocated to foraging patches electronically and GUDs from seeds left behind in resource patches. From these, we estimated handling times, attack rates and quitting harvest rates (QHRs). Gerbils displayed greater vigilance (lower attack rates) at brighter moon phases (full < wane < wax < new). Similarly, they displayed higher GUDs at brighter moon phases (wax > full > new > wane). Finally, gerbils displayed higher QHRs at new and waxing moon phases. Differences across moon phases not only reflect changing time allocation and vigilance, but changes in the state of the foragers and their marginal value of energy. Early in the lunar cycle, gerbils rely on vigilance and sacrifice state to avoid risk; later they defend state at the cost of increased time allocation; finally their state can recover as safe opportunities expand. In the predator–prey foraging game, foxes may contribute to these patterns of behaviours by modulating their own activity in response to the opportunities presented in each moon phase. PMID:20053649

  13. Aqueous extract of Cordyceps alleviates cerebral ischemia-induced short-term memory impairment in gerbils.

    PubMed

    Lee, Sang-Hak; Ko, Il-Gyu; Kim, Sung-Eun; Hwang, Lakkyong; Jin, Jun-Jang; Choi, Hyun-Hee; Kim, Chang-Ju

    2016-04-01

    Cerebral ischemia is caused by reduced cerebral blood flow due to a transient or permanent cerebral artery occlusion. Ischemic injury in the brain leads to neuronal cell death, and eventually causes neurological impairments. Cordyceps, the name given to the fungi on insects, has abundant useful natural products with various biological activities. Cordyceps is known to have nephroprotective, hepatoprotective, anti-inflammatory, antioxidative, and antiapoptotic effects. We investigated the effects of Cordyceps on short-term memory, neuronal apoptosis, and cell proliferation in the hippocampal dentate gyrus following transient global ischemia in gerbils. For this study, a step-down avoidance test, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, immunohistochemistry for caspase-3 and 5-bromo-2'-de-oxyuridine, and western blot for Bax, Bcl-2, brain-derived neurotrophic factor (BDNF), and tyrosin kinase B were performed. In the present study, Cordyceps alleviated cerebral ischemia-induced short-term memory impairment. Cordyceps showed therapeutic effects through inhibiting cerebral ischemia-induced apoptosis in the hippocampus. Cordyceps suppressed cerebral ischemia-induced cell proliferation in the hippocampal dentate gyrus due to the reduced apoptotic neuronal cell death. Cordyceps treatment also enhanced BDNF and TrkB expressions in the hippocampus of ischemic gerbils. It can be suggested that Cordyceps overcomes cerebral ischemia-induced neuronal apoptosis, thus facilitates recovery following cerebral ischemia injury. PMID:27162767

  14. Aqueous extract of Cordyceps alleviates cerebral ischemia-induced short-term memory impairment in gerbils

    PubMed Central

    Lee, Sang-Hak; Ko, Il-Gyu; Kim, Sung-Eun; Hwang, Lakkyong; Jin, Jun-Jang; Choi, Hyun-Hee; Kim, Chang-Ju

    2016-01-01

    Cerebral ischemia is caused by reduced cerebral blood flow due to a transient or permanent cerebral artery occlusion. Ischemic injury in the brain leads to neuronal cell death, and eventually causes neurological impairments. Cordyceps, the name given to the fungi on insects, has abundant useful natural products with various biological activities. Cordyceps is known to have nephroprotective, hepatoprotective, anti-inflammatory, antioxidative, and antiapoptotic effects. We investigated the effects of Cordyceps on short-term memory, neuronal apoptosis, and cell proliferation in the hippocampal dentate gyrus following transient global ischemia in gerbils. For this study, a step-down avoidance test, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, immunohistochemistry for caspase-3 and 5-bromo-2′-de-oxyuridine, and western blot for Bax, Bcl-2, brain-derived neurotrophic factor (BDNF), and tyrosin kinase B were performed. In the present study, Cordyceps alleviated cerebral ischemia-induced short-term memory impairment. Cordyceps showed therapeutic effects through inhibiting cerebral ischemia-induced apoptosis in the hippocampus. Cordyceps suppressed cerebral ischemia-induced cell proliferation in the hippocampal dentate gyrus due to the reduced apoptotic neuronal cell death. Cordyceps treatment also enhanced BDNF and TrkB expressions in the hippocampus of ischemic gerbils. It can be suggested that Cordyceps overcomes cerebral ischemia-induced neuronal apoptosis, thus facilitates recovery following cerebral ischemia injury. PMID:27162767

  15. Nonesterified phytosterols dissolved and recrystallized in oil reduce plasma cholesterol in gerbils and humans.

    PubMed

    Hayes, K C; Pronczuk, A; Perlman, D

    2004-06-01

    When free phytosterols are adequately heated and then cooled in fat, they recrystallize and are rendered bioavailable for blocking cholesterol absorption. To extend the application of phytosterols to fried foods, the activity of these modified crystals was assessed in 2 experiments with 26 male gerbils fed purified diets containing 0.15 g/100 g cholesterol with or without 0.75 g/100 g free phytosterols. The heat-modified soybean sterols were added directly to the diet (Expt. 1) or as phytosterol-enriched potato chips (Expt. 2). In the gerbil experiments, only the diet containing phytosterols significantly reduced plasma cholesterol (35-48%) and the total cholesterol/HDL cholesterol (HDL-C) ratio (40%), as well as hepatic cholesterol esters (80%). In a subsequent human study, subjects (n = 7) consumed two 28-g servings of tortilla chips fried in oil with or without phytosterols that provided 0 or 1.5 g/d for 4-wk periods in a crossover design (Expt. 3). During consumption of the phytosterol-enriched chips, significant reductions in plasma cholesterol (10%) and LDL cholesterol (15%) were achieved without affecting HDL-C. This novel means of delivering free phytosterols proved to be both functionally efficient and effective. PMID:15173402

  16. Effect of low level laser therapy (LLLT) on ouabain induced auditory neuropathy in gerbils (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Rhee, Chung-Ku; Bae, Sung Huyn; Chang, So-Young; Chung, Phil-Sang; Jung, Jae-Yun

    2016-02-01

    Aim: to investigate effectiveness of Low level laser therapy (LLLT) in rescueing ouabain induced spiral ganglion cell damage using Mongolian gerbils. Methods: Animals were divided into 3 groups; Control, Ouabain, Ouabain + LLLT group. Auditory neuropathy was induced by topical application of ouabain (1 mmol/L, 3uL) on the round window membrane in gerbils. Transmeatal LLLT was irradiated into the right ear for 1h (200mW, 720 J) daily for 7d in Ouabain + LLLT group. Before and 7 days after ouabain application, hearing was evaluated using both ABR and distortion product otoacoustic emissions (DPOAE). Seven days after ouabain application, animals were sacrificed to evaluate the morphological changes of cochlea using cochlear section image and whole mount Immunofluorescent staining. Results: DPOAE tests were normal in all animals after ouabain topical treatment indicating intact outer hair cells. Ouabain group showed ABR threshold increase compared with control group. Ouabain+LLLT group showed significant improvement of ABR threshold compared to ouabain only group. H and E stains of mid-modiolar section of cochlear showed spiral ganglion cells, neurofilaments, and post synaptic receptor counts were decreased while inner and outer hair cells were preserved in ouabain group. Ouabain +LLLT group showed higher numbers of spiral ganglion cells, density of neurofilaments and post synaptic receptor counts compared to ouabain group. Conclusions: The results demonstrated that LLLT was effective to rescue ouabain-induced spiral ganglion neuropathy.

  17. Suppressibility of the 2f1-f2 stimulated acoustic emissions in gerbil and man.

    PubMed

    Brown, A M; Kemp, D T

    1984-01-01

    The suppression tuning properties of the oto-acoustic distortion product emission, 2f1-f2 have been measured in the ear canal of gerbil and man. The results show the acoustic response to be suppressible in a similar, frequency-dependent manner in both species. Frequencies near to those of the stimulating tones are most effective in suppressing the response. Derived iso-suppression tuning curves have Q10dB values of between 1 and 6. Suppressor tones having frequencies near to f2 (the higher frequency stimulus) make a contribution to the tuning curve which is largely independent of the stimulus intensity and the frequency ratio between the two primary tones. Suppressors having f1-associated frequencies produce a variable amount of suppression depending on the stimulus parameters chosen. No specific suppression feature could be associated with suppressors near to 2f1-f2. The frequency selectivity of the acoustic DP generation mechanism shown by this study indicates a close association with the transduction mechanism. The demonstration of comparable signals in gerbil and man facilitates the direct transfer of laboratory results to the study of human ears. PMID:6706860

  18. Localization of melanopsin-immunoreactive cells in the Mongolian gerbil retina.

    PubMed

    Jeong, Mi-Jin; Jeon, Chang-Jin

    2015-11-01

    Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) are involved in circadian rhythm and pupil responses. The purpose of this study was to reveal the organization of melanopsin-immunoreactive (IR) neurons in the Mongolian gerbil retina using immunocytochemistry. Melanopsin-IR cells were primarily located in the ganglion cell layer (GCL; M1c; 75.15%). Many melanopsin-IR cells were also observed in the inner nuclear layer (INL; M1d; 22.28%). The M1c and M1d cell types extended their dendritic processes into the OFF sublayer of the inner plexiform layer (IPL). We rarely observed bistratified cells (M3; 2.56%) with dendrites in both the ON and OFF sublayers of the IPL. Surprisingly, we did not observe M2 cells which are well observed in other rodents. Melanopsin-IR cell somas were small to medium in size and had large dendritic fields. They had 2-5 primary dendrites that branched sparingly and had varicosities. Melanopsin-IR cell density was very low: they comprised 0.50% of the total ganglion cell population. Moreover, none of the melanopsin-IR cells expressed calbindin-D28K, calretinin, or parvalbumin. These results suggest that in the Mongolian gerbil, melanopsin-IR cells are expressed in a very small RGC subpopulation, and are independent of calcium-binding proteins-containing RGCs. PMID:26083722

  19. Measurement of the Three-Dimensional Vibration Motion of the Ossicular Chain in the Living Gerbil

    NASA Astrophysics Data System (ADS)

    Decraemer, Willem F.; de La Rochefoucauld, Ombeline; Olson, Elizabeth S.

    2011-11-01

    In previous studies 3D motion of the middle-ear ossicles in cat and human temporal bone were explored but models for hearing research has shifted in the last decades to smaller mammals and gerbil in particular has become a hearing model of first choice. In the present study we have measured with an optical interferometer the 3D motion of the malleus and incus in anesthetized gerbil for sound of moderate intensity (90 dB SPL) in a broad frequency range. To access the malleus and incus the pars flaccida was completely removed exposing the neck and head of the malleus and the incus from the malleus-incus joint to the long process of the incus and the plate of the lenticular process. In a previous study an approach through a hole in the bullar wall was used to study the stapes motion so that we now have a complete picture of the middle ear motion. In both approaches vibration measurements were done at 6 to 7 points per ossicle while the angle of observation was varied over approximately 30 degrees to enable calculation of the 3D velocity components. Knowledge of middle ear motion is of great importance in understanding how the middle ear transforms the acoustical input from the ear canal to the cochlea.

  20. Blockade of intracellular actions of calcium may protect against ischaemic damage to the gerbil brain.

    PubMed Central

    Asano, T.; Ikegaki, I.; Satoh, S.; Mochizuki, D.; Hidaka, H.; Suzuki, Y.; Shibuya, M.; Sugita, K.

    1991-01-01

    1. The brain cytoprotective effects of a putative calcium-associated protein kinase inhibitor, HA1077, as well as a calcium entry blocker nicardipine were evaluated in models of cerebral ischaemia in Mongolian gerbils. Morphological changes characterizing delayed neuronal death of selectively vulnerable CA1 pyramidal neurones in the hippocampus of the Mongolian gerbil brain occurred 7 days after transient bilateral occlusion of the common carotid arteries. 2. A single injection of HA1077 (1 and 3 mg kg-1, i.p.) 5 min after the occlusion led to a dose-dependent protection of the CA1 neurones. Repeated administrations of HA1077 (1 and 3 mg kg-1, i.p., twice daily for 7 days post-ischaemia) revealed an increase in the number of normal cells, compared to findings with a single administration. 3. In contrast to HA1077, nicardipine (0.3 and 1 mg kg-1, i.p.) did not reduce neuronal degeneration. 4. HA1077 did not interact with the ion channel within which MK-801 binds, as determined by receptor binding. 5. The calcium ionophore, A23187, caused a tonic contraction in canine cerebral arterial strips. HA1077, but not nicardipine, relaxed the A23187-induced contraction, concentration-dependently. 6. These results suggest that blockade of the intracellular actions of calcium may provide protection against ischaemic damage in the brain. Images Figure 1 PMID:1912980

  1. Selective acceleration of arachidonic acid reincorporation into brain membrane phospholipid following transient ischemia in awake gerbil.

    PubMed

    Rabin, O; Chang, M C; Grange, E; Bell, J; Rapoport, S I; Deutsch, J; Purdon, A D

    1998-01-01

    Awake gerbils were subjected to 5 min of forebrain ischemia by clamping the carotid arteries for 5 min and then allowing recirculation. Radiolabeled arachidonic or palmitic acid was infused intravenously for 5 min at the start of recirculation, after which the brains were prepared for quantitative autoradiography or chemical analysis. Dilution of specific activity of the acyl-CoA pool was independently determined for these fatty acids in control gerbils and following 5 min of ischemia and 5 min of reperfusion. Using a quantitative method for measuring regional in vivo fatty acid incorporation into and turnover within brain phospholipids and determining unlabeled concentrations of acyl-CoAs following recirculation, it was shown that reperfusion after 5 min of ischemia was accompanied by a threefold increase compared with the control in the rate of reincorporation of unlabeled arachidonate that had been released during ischemia, whereas reincorporation of released palmitate was not different from the control. Selective and accelerated reincorporation of arachidonate into brain phospholipids shortly after ischemia may ameliorate specific deleterious effects of arachidonate and its metabolites on brain membranes. PMID:9422378

  2. [Contractile properties of fibers and cytoskeletal proteins of gerbil's hindlimb muscles after space flight].

    PubMed

    Lipets, E N; Ponomareva, E V; Ogneva, I V; Vikhliantsev, I M; Karaduleva, E V; Kratashkina, N L; Kuznetsov, S L; Podlubnaia, Z A; Shenkman, B S

    2009-01-01

    The work had the goal to compare the microgravity effects on gerbil's muscles-antagonists, m. soleus and m. tibialis anterior. The animals were exposed in 12-d space microgravity aboard Earth's artificial satellite "Foton-M3". Findings of the analysis of single skinned fibers contractility are 19.7% diminution of the diameter and 21.8% loss of the total contractive force of m. soleus fibers post flight. However, there was no significant difference in calcium sensitivity which agrees with the absence of changes in the relative content of several major cytoskeletal proteins (titin and nebulin ratios to heavy chains of myosin were identical in the flight and control groups) and a slight shifting of the myosin phenotype toward the "fast type" (9%, p < 0.05). These parameters were mostly unaffected by the space flight in m. tibialis anterior. To sum up, the decline of contractility and diminution of gerbil's myofibers after the space flight were less significant as compared with rats and did not impact the sytoskeletal protein ratios. PMID:19711860

  3. Prepubertal exposure to bisphenol-A induces ERα upregulation and hyperplasia in adult gerbil female prostate

    PubMed Central

    Campos, Mônica S; Galvão, André L V; Rodríguez, Daniel A O; Biancardi, Manoel F; Marques, Mara R; Vilamaior, Patrícia S L; Santos, Fernanda C A; Taboga, Sebastião R

    2015-01-01

    Prostate physiology is highly dependent on oestrogenic and androgenic homeostasis. Interferences in this equilibrium, especially in early periods of life, may disrupt the prostate and increase the susceptibility to the development of diseases with ageing. Taking this into account, and considering the increase of environmental chemicals with endocrine-disrupting potential such as bisphenol-A (BPA), this study aimed to evaluate the prostates of adult female gerbils exposed to BPA and BPA plus testosterone from pubertal to adult periods. Morphological, stereological and chemical analyses revealed that long-term BPA exposure, even in environmental dosages, increases the proliferative status of the prostate, increases the number of ERα-positive stromal cells and elicits the development of prostatic hyperplasia in adult female gerbils. Moreover, we also observed that the association with testosterone did not increase the proliferative status of the gland, which shows that low levels of BPA are enough to cause an oestrogenic disruption of the prostate in young adults. This evidence suggests that this oestrogenic endocrine disruptor may increase the susceptibility to prostatic disorders with ageing. PMID:26098999

  4. Seasonal changes in testicular contents and plasma concentrations of androgens in the desert gerbil (Gerbillus gerbillus).

    PubMed

    Khammar, F; Brudieux, R

    1987-07-01

    Gerbils were caught in the Béni-Abbès area (Algeria). Testicular endocrine activity was highest in spring (testicular wt 298 +/- 10 mg; seminal vesicle wt 603 +/- 62 mg; testicular testosterone and androstenedione content 9.2 +/- 1.7 and 0.5 +/- 0.1 ng/testis; plasma testosterone 832 +/- 200 pg/ml). Values decreased in summer, were lowest in late summer and in autumn (84 +/- 17 mg; 40 +/- 14 mg; 0.20 +/- 0.06 and 0.02 +/- 0.01 ng/testis; 228 +/- 54 pg/ml, respectively) and increased again in winter (December-January). The onset of testicular endocrine activity was concomitant with the lowest temperatures and the shortest photoperiod; it increased when temperatures and daylength were increasing and began to decline when temperatures and photoperiod were still maximal. These seasonal changes in the endocrine activity of the testis of the gerbil differ from those of the sand rat inhabiting the same area. PMID:3656287

  5. [Electrogenic activity of Na-K-ATPase and calcium ions in m. soleus fibers of rats and Mongolian gerbil during simulation of gravitational unloading].

    PubMed

    Kravtsova, V V; Ogneva, I V; Altaeva, E G; Razgovorova, I A; Tiapkina, O V; Nikol'skiĭ, E E; Shenkman, B S; Krivoĭ, I I

    2010-01-01

    Some of the electrophysiological parameters of m. soleus of rat and Mongolian gerbil, and Ca ions content in fiber myoplasm were compared in different periods of gravitational unloading simulated by tail-suspension. No difference was found between the control animals as for membrane potential at rest, electrogenic activities of Na-K-ATPase and its isoforms, and input resistance of m. soleus fibers. At the same time, unlike rats, gerbils exhibited a substantial Ca decrease in myoplasm. From day one to 14 of gravitational unloading the pace of electrophysiological changes in gerbil's m. soleus was noticeably slower than of rat's, whereas Ca ions depositing in myoplasm was observed in both species already at the beginning ofsuspension. Analysis of the results suggests that adaptive changes in m. soleus of Mongolian gerbil and rat during simulated gravitational unloading are fundamentally different due to, probably, peculiar water-electrolyte metabolism, type of locomotion, and other factors which are still unclear. PMID:20799658

  6. Spontaneous activity in the developing gerbil auditory cortex in vivo involves GABAergic transmission

    PubMed Central

    Kotak, Vibhakar C.; Péndola, L. Martín; Rodríguez-Contreras, Adrián

    2012-01-01

    A salient feature of the developing brain is that spontaneous oscillations (SOs) and waves may influence the emergence of synaptic connections. Whilst gamma-amino butyric acid (GABA) produces depolarization and may support SOs in the neurons of developing rodents, it elicits hyperpolarization and diminishes SOs in developing gerbil auditory cortex (ACx). Therefore, we asked whether SOs exist in developing gerbil ACx in vivo and if GABAergic involvement can be manipulated. In vivo extracellular recordings in P3-5 ACx revealed SOs with longer burst durations and shorter inter-event intervals compared to ACx SOs in slices. ACx was then validated by gross anatomical features and lesions created at the in vivo recording site that corresponded with the electrophysiological coordinates of thalamorecipient ACx in slices. Further, NeuroVue Red, a lipophilic dye loaded at the in vivo recording sites, stained anatomically identifiable fiber tracks between the ACx and the auditory thalamus, medial geniculate body (MG). Separately, to chronically perturb GABAergic role in SOs, P2-5 pups were administered daily with GABAA receptor blocker, bicuculline (BIC). We then recorded from P14-17 ACx neurons in slices generated after hearing onset. ACx neurons from BIC-administered pups exhibited spontaneous action potentials in contrast to subthreshold synaptic potentials in neurons from sham-injected animals. Finally, to elucidate whether the gap junction blocker mefloquine (MFQ) previously shown to dampen ACx SOs in slices affected GABAergic transmission, MFQ was acutely applied in P3-5 slices while spontaneous inhibitory postsynaptic currents (sIPSCs) were recorded. Whereas MFQ increased the amplitude and frequency of sIPSCs in ACx neurons, the broad-spectrum gap junction blocker carbenoxolone decreased sIPSC amplitudes only. Together, we show that P2-5 gerbil ACx can endogenously generate SOs in vivo. Persistence of activity in ACx in P14-17 slices from pups administered with BIC at

  7. In Vivo Impedance of the Gerbil Cochlear Partition at Auditory Frequencies

    PubMed Central

    Dong, Wei; Olson, Elizabeth S.

    2009-01-01

    Abstract The specific acoustic impedance of the cochlear partition was measured from 4 to 20 kHz in the basal turn of the gerbil cochlea, where the best frequency is ∼40 kHz. The acoustic impedance was found as the ratio of driving pressure to velocity response. It is the physical attribute that governs cochlear mechanics and has never before been directly measured, to our knowledge. The basilar membrane velocity was measured through the transparent round window membrane. Simultaneously, the intracochlear pressure was measured close to the stapes and quite close to the cochlear partition. The impedance phase was close to −90° and the magnitude decreased with frequency, consistent with stiffness-dominated impedance. The resistive component of the impedance was relatively small. Usually the resistance was negative at frequencies below 8 kHz; this unexpected finding might be due to other vibration modes within the cochlear partition. PMID:19720011

  8. Acute and chronic effects of beta9-tetrahydrocannabinol on seizures in the gerbil.

    PubMed

    Ten Ham, M; Loskota, W J; Lomax, P

    1975-03-01

    Beta9-THC was injected daily for 6 days into gerbils from our breeding colony that exhibit spontaneous epileptiform seizures. At a dose of 20 mg/kg no effect was seen on the latency, duration or severity of the seizures induced after 1 and 6 days of treatment. Delta9-THC (50 mg/kg) completely abolished the seizures after a single injection but tolerance developed to this effect so that no protection was afforded after 6 daily doses. Severe toxic signs were evident at the higher dose level with marked depression of spontaneous motor activity. The toxic effect increased progressively with chronic treatment and half the animals failed to survive. PMID:1126373

  9. Potential effect of chronic Helicobacter pylori infection on glucose metabolism of Mongolian gerbils

    PubMed Central

    Yang, Zhen; Li, Wei; He, Cong; Xie, Chuan; Zhu, Yin; Lu, Nong-Hua

    2015-01-01

    AIM: To assess the effect of Helicobacter pylori (H. pylori) infection on metabolic parameters in Mongolian gerbils. METHODS: A total of 40 male, 5- to 8-wk-old, specific-pathogen-free Mongolian gerbils (30-50 g) were randomly allocated into two groups: a control group (n = 20) and an H. pylori group (n = 20). After a two-week acclimation period, the control group was administered Brucella broth and the H. pylori group was challenged intra-gastrically five times every other day with approximately 109/CFU H. pylori ATCC43504 (CagA+, VacA+). Each group was then divided into two subgroups, which were sacrificed at either 6 or 12 mo. The control and H. pylori subgroups each contained 10 Mongolian gerbils. Body weight, abdominal circumference, and body length were measured, and body mass index (BMI) and Lee’s index were calculated. Biochemical assays were used to detect serum indexes, including glucose, glycated hemoglobin (GHb), glycated hemoglobin A1c (HbA1c), triacylglycerol, and total cholesterol, using an automatic biochemistry analyzer. Inflammatory cytokines, including interleukin (IL)-1β, IL-2, IL-4, IL-10, IL-12, tumor necrosis factor-α (TNF-α) and interferon (IFN)-γ, were assayed using ELISA. The expression of insulin and insulin-like growth factor 1 (IGF-1) was detected by immunohistochemistry, and islet apoptosis was measured using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. RESULTS: At each time point, body weight, abdominal circumference, BMI, and Lee’s index were increased after H. pylori infection. However, these differences were not significant. H. pylori infection significantly increased the GHb (5.45 ± 0.53 vs 4.98 ± 0.22, P < 0.05) and HbA1c (4.91 ± 0.61 vs 4.61 ± 0.15, P < 0.05) levels at 12 mo. We observed no significant differences in serum biochemical indexes, including fasting blood glucose, triacylglycerol and total cholesterol, at 6 or 12 mo after infection. H. pylori infection

  10. Response properties of gerbil otolith afferents to small angle pitch and roll tilts

    NASA Technical Reports Server (NTRS)

    Dickman, J. D.; Angelaki, D. E.; Correia, M. J.

    1991-01-01

    The responses from isolated single otolith afferent fibers were obtained to small angle sinusoidal pitch and roll tilts in anesthetized gerbils. The stimulus directions that produced the maximum (response vector) and minimum response sensitivities were determined for each otolith afferent, with response vectors for the units being spread throughout the horizontal plane, similar to those reported for other species. A breadth of tuning measure was derived, with narrowly tuned neurons responding maximally to stimulation in one direction and minimally along an orthogonal ('null') direction. Most (approximately 80%) otolith afferents are narrowly tuned, however, some fibers were broadly tuned responding significantly to stimulations in any direction in the horizontal plane. The number of broadly tuned otolith afferents (approximately 20%) differs significantly from the more substantial number of broadly tuned vestibular nuclei neurons (88%) recently reported in rats.

  11. Low-frequency finite-element modeling of the gerbil middle ear.

    PubMed

    Elkhouri, Nidal; Liu, Hengjin; Funnell, W Robert J

    2006-12-01

    The gerbil is a popular species for experimental middle-ear research. The goal of this study is to develop a 3D finite-element model to quantify the mechanics of the gerbil middle ear at low frequencies (up to about 1 kHz). The 3D reconstruction is based on a magnetic resonance imaging dataset with a voxel size of about 45 microm, and an x-ray micro-CT dataset with a voxel size of about 5.5 microm, supplemented by histological images. The eardrum model is based on moiré shape measurements. Each individual structure in the model was assumed to be homogeneous with isotropic, linear, and elastic material properties derived from a priori estimates in the literature. The behavior of the finite-element model in response to a uniform acoustic pressure on the eardrum of 1 Pa is analyzed. Sensitivity tests are done to evaluate the significance of the various parameters in the finite-element model. The Young's modulus and the thickness of the pars tensa have the most significant effect on the load transfer between the eardrum and the ossicles and, along with the Young's modulus of the pedicle and stapedial annular ligament, on the displacements of the stapes. Overall, the model demonstrates good agreement with low-frequency experimental data. For example, (1) the maximum footplate displacement is about 35 nm; (2) the umbo/stapes displacement ratio is found to be about 3.5; (3) the motion of the stapes is predominantly piston-like; and (4) the displacement pattern of the eardrum shows two points of maximum displacement, one in the posterior region and one in the anterior region. The effects of removing or stiffening the ligaments are comparable to those observed experimentally. PMID:17043944

  12. Host defence versus intraspecific competition in the regulation of infrapopulations of the flea Xenopsylla conformis on its rodent host Meriones crassus.

    PubMed

    Hawlena, Hadas; Abramsky, Zvika; Krasnov, Boris R; Saltz, David

    2007-07-01

    Mechanisms that regulate parasite populations may influence the evolution of hosts and parasites, as well as the stability of host-parasite dynamics but are still poorly understood. A manipulation experiment on the grooming ability of rodent hosts (Meriones crassus) and flea (Xenopsylla conformis) densities on these hosts successfully disentangled two possible regulating mechanisms: (i) behavioural defence of the host and (ii) intraspecific competition among parasites, and revealed their importance in suppressing the feeding of fleas. Moreover, the results suggest that flea competition is direct and is not mediated by host grooming, immune response, or parasite-induced damage to the host. These mechanisms, together with interspecific competition and density-dependent parasite-induced host damage, may limit the parasite burden on an individual host and may prevent parasites from overexploiting their host population. PMID:17362966

  13. Paradoxical role of Helicobacter pylori infection: protective effect against ethanol-induced gastric mucosal injury in Mongolian gerbils.

    PubMed

    Sugiyama, A; Ikeno, T; Ishida, K; Maruta, F; Murakami, M; Sato, T; Saito, H; Ishizone, S; Kawasaki, S; Ota, H; Katsuyama, T

    2001-11-01

    We investigated the effect of ethanol (a representative necrotizing agent) on gastritis induced by Helicobacter pylori infection in Mongolian gerbils. Seventy-eight gerbils were used. Four and 12 weeks after H. pylori inoculation, 30% ethanol was administered into the stomach. The stomachs were removed after 30 min, the intramucosal prostaglandin (PG) E2 concentration was measured, and histopathology was recorded. H. pylori infection caused chronic active gastritis, gastric erosion, hypersecretion of mucin from gland mucus cells, and a rise in the activity of intramucosal PGE2. After ethanol administration, gastric erosion was significantly less in animals infected with H. pylori than in uninfected animals. In conclusion, in the early stage of H. pylori infection, accentuation of intramucosal PGE2 and hypersecretion of mucin from gland mucus cells have a protective effect against gastric mucosal injury induced by necrotizing agents. PMID:11713948

  14. The Protective Effects of 18β-Glycyrrhetinic Acid on Helicobacter pylori-Infected Gastric Mucosa in Mongolian Gerbils

    PubMed Central

    Cao, Donghui; Jiang, Jing; You, Lili; Jia, Zhifang; Tsukamoto, Tetsuya; Cai, Hongke; Wang, Shidong; Hou, Zhen; Suo, Yue-er; Cao, Xueyuan

    2016-01-01

    18β-Glycyrrhetinic acid (GRA), a major component of Glycyrrhiza glabra, is widely used therapeutically in clinic. In this study, the effect of GRA on Helicobacter pylori- (H. pylori-) infected gastritis was investigated in Mongolian gerbils in vivo. The gerbils were randomly divided into groups: uninfected; H. pylori-infected; H. pylori + antibiotics (clarithromycin, amoxicillin, and esomeprazole); and H. pylori + GRA. The gastric intraluminal pH value, histopathological changes, and the expression levels of inflammation-related cytokines (IL-1β, TNF-α, COX-2, and iNOS) were investigated. The results showed that, in the H. pylori + GRA group, the intraluminal gastric pH value was lower (2.14 ± 0.08 versus 3.17 ± 0.23, P < 0.05), erosion and hyperplasia were alleviated, the infiltration of neutrophils and mononuclear cells was attenuated (P < 0.05), and the expression levels of TNF-α, IL-1β, COX-2, and iNOS were decreased (P < 0.05) compared with the H. pylori-infected group. There was no significant difference in results between the H. pylori + GRA group and the H. pylori + antibiotics group. This study indicated that GRA significantly attenuated H. pylori-infected gastritis in gerbils and has the potential to be developed as a new therapeutic drug. PMID:27006947

  15. Effect of swine hepatitis E virus on the livers of experimentally infected Mongolian gerbils by swine hepatitis E virus.

    PubMed

    Yang, Yifei; Shi, Ruihan; She, Ruiping; Soomro, Majid Hussain; Mao, Jingjing; Du, Fang; Zhao, Yue; Liu, Can

    2015-10-01

    Previous studies have shown that hepatitis E virus (HEV) can be transmitted between rats, pigs, cattle, rabbits, chicken, cats, and deer. Because wild and domestic rodents have anti-HEV antibodies, they are considered potential reservoirs of HEV. In the current study, Mongolian gerbils were experimentally infected with swine hepatitis E virus and the effects of this infection were investigated. After inoculation with HEV, the liver-to-body weight ratio increased at 7 dpi. Mongolian gerbils demonstrated significant increase (p<0.05) in Aspartate Transaminase (AST), alanine transaminase (ALT) and total bilirubin (T-BIL) concentrations in the sera, and HEV IgG was detected at 21 days post-inoculation (dpi). Real-time PCR revealed that the copies of HEV RNA in the liver were detected at 7 dpi, and peaked at 28 dpi at a concentration of 7.73 logs g(-1). Using both light and electron microscopy, hepatic lesions were observed in the HEV inoculated animals. In the experimental group, characteristic viral hepatitis lesions were prominent in the liver. HEV antigen was detected in the liver by immunohistochemistry, and HEV ORF3 antigen was detectable in liver by Western blot. These results clearly demonstrate that viral load of HEV in livers was dynamic, and ultrastructural hepatic injury in HEV infected Mongolian gerbils and anti-HEV IgG positive seroconversion were observed during infection. PMID:26093307

  16. A field test of the centrifugal community organization model using psammophilic gerbils in Israel's southern coastal plain

    USGS Publications Warehouse

    Wasserberg, G.; Kotler, B.P.; Morris, D.W.; Abramsky, Z.

    2007-01-01

    Background: An optimal habitat selection model called centrifugal community organization (CCO) predicts that species, although they have the same primary habitat, may co-exist owing to their ability to use different secondary habitats. Goal: Test the predictions of CCO with field experiments. Species: The Egyptian sand gerbil (40 g), Gerbillus pyramidum, and Allenby's gerbil (25 g), G. andersoni allenbyi. Site: Ashdod sand dunes in the southern coastal plain of Israel. Three sandy habitats are present: shifting, semi-stabilized, and stabilized sand. Gerbils occupied all three habitats. Methods: We surveyed rodent abundance, activity levels, and foraging behaviour while experimentally removing G. pyramidum. Results: Three predictions of the CCO model were supported. Both species did best in the semi-stabilized habitat. However, they differed in their secondary habitats. Gerbillus pyramidum preferred the shifting sand habitat, whereas G. a. allenbyi preferred the stabilized habitat. Habitat selection by both species depended on density. However, in contrast to CCO, G. pyramidum dominated the core habitat and excluded G. a. allenbyi. We term this variant of CCO, 'asymmetric CCO'. Conclusions: The fundamental feature of CCO appears valid: co-existence may result not because of what each competing species does best, but because of what they do as a back-up. But in contrast to the prediction of the original CCO model, all dynamic traces of interaction can vanish if the system includes interference competition. ?? 2007 Gideon Wasserberg.

  17. Dependence of the Startle Response on Temporal and Spectral Characteristics of Acoustic Modulatory Influences in Rats and Gerbils

    PubMed Central

    Steube, Natalie; Nowotny, Manuela; Pilz, Peter K. D.; Gaese, Bernhard H.

    2016-01-01

    The acoustic startle response (ASR) and its modulation by non-startling prepulses, presented shortly before the startle-eliciting stimulus, is a broadly applied test paradigm to determine changes in neural processing related to auditory or psychiatric disorders. Modulation by a gap in background noise as a prepulse is especially used for tinnitus assessment. However, the timing and frequency-related aspects of prepulses are not fully understood. The present study aims to investigate temporal and spectral characteristics of acoustic stimuli that modulate the ASR in rats and gerbils. For noise-burst prepulses, inhibition was frequency-independent in gerbils in the test range between 4 and 18 kHz. Prepulse inhibition (PPI) by noise-bursts in rats was constant in a comparable range (8–22 kHz), but lower outside this range. Purely temporal aspects of prepulse–startle-interactions were investigated for gap-prepulses focusing mainly on gap duration. While very short gaps had no (rats) or slightly facilitatory (gerbils) influence on the ASR, longer gaps always had a strong inhibitory effect. Inhibition increased with durations up to 75 ms and remained at a high level of inhibition for durations up to 1000 ms for both, rats and gerbils. Determining spectral influences on gap-prepulse inhibition (gap-PPI) revealed that gerbils were unaffected in the limited frequency range tested (4–18 kHz). The more detailed analysis in rats revealed a variety of frequency-dependent effects. Gaps in pure-tone background elicited constant and high inhibition (around 75%) over a broad frequency range (4–32 kHz). For gaps in noise-bands, on the other hand, a clear frequency-dependency was found: inhibition was around 50% at lower frequencies (6–14 kHz) and around 70% at high frequencies (16–20 kHz). This pattern of frequency-dependency in rats was specifically resulting from the inhibitory effect by the gaps, as revealed by detailed analysis of the underlying startle amplitudes. An

  18. Dependence of the Startle Response on Temporal and Spectral Characteristics of Acoustic Modulatory Influences in Rats and Gerbils.

    PubMed

    Steube, Natalie; Nowotny, Manuela; Pilz, Peter K D; Gaese, Bernhard H

    2016-01-01

    The acoustic startle response (ASR) and its modulation by non-startling prepulses, presented shortly before the startle-eliciting stimulus, is a broadly applied test paradigm to determine changes in neural processing related to auditory or psychiatric disorders. Modulation by a gap in background noise as a prepulse is especially used for tinnitus assessment. However, the timing and frequency-related aspects of prepulses are not fully understood. The present study aims to investigate temporal and spectral characteristics of acoustic stimuli that modulate the ASR in rats and gerbils. For noise-burst prepulses, inhibition was frequency-independent in gerbils in the test range between 4 and 18 kHz. Prepulse inhibition (PPI) by noise-bursts in rats was constant in a comparable range (8-22 kHz), but lower outside this range. Purely temporal aspects of prepulse-startle-interactions were investigated for gap-prepulses focusing mainly on gap duration. While very short gaps had no (rats) or slightly facilitatory (gerbils) influence on the ASR, longer gaps always had a strong inhibitory effect. Inhibition increased with durations up to 75 ms and remained at a high level of inhibition for durations up to 1000 ms for both, rats and gerbils. Determining spectral influences on gap-prepulse inhibition (gap-PPI) revealed that gerbils were unaffected in the limited frequency range tested (4-18 kHz). The more detailed analysis in rats revealed a variety of frequency-dependent effects. Gaps in pure-tone background elicited constant and high inhibition (around 75%) over a broad frequency range (4-32 kHz). For gaps in noise-bands, on the other hand, a clear frequency-dependency was found: inhibition was around 50% at lower frequencies (6-14 kHz) and around 70% at high frequencies (16-20 kHz). This pattern of frequency-dependency in rats was specifically resulting from the inhibitory effect by the gaps, as revealed by detailed analysis of the underlying startle amplitudes. An interaction

  19. Evidence for rodent-common and species-typical limb and digit use in eating, derived from a comparative analysis of ten rodent species.

    PubMed

    Whishaw, I Q; Sarna, J R; Pellis, S M

    1998-11-01

    Order Rodentia comprises a vast portion of mammalian species (1814 species), which occupy extremely diverse habitats requiring very distinct motor specializations (e.g. burrowing, hopping, climbing, flying and swimming). Although early classification of paw use ability suggests rodents are impoverished relative to primates and make little use of their paws, there have been no systematic investigations of paw use in rodents. The present study was undertaken to describe limb/paw movements in a variety of common rodents. The movements used for handling sunflower seeds and other foods were videorecorded and analyzed in the guinea pig (Cavia porcellus), Mongolian gerbil (Meriones unguiculatus), Syrian hamster (Mesocricetus auratus), laboratory mouse (Mus musculus), laboratory rat (Rattus norvegicus), gray squirrel (Sciurus carolinensis), red squirrel (Tamiasciurus hudsonicus), Richardson's ground squirrel (Spermophilus richardsonni), prairie dog (Cynomus parvidens), and Canadian beaver (Castor americanus). The results suggested five order-common movements of food handling: (1) locating food by sniffing, (2) grasping food by mouth, (3) sitting back on the haunches to eat, (4) grasping the food using an elbow-in movement, and (5) manipulate the food with the digits. Different species displayed species-typical specializations including (1) bilateral grasping with the paws (gerbil), (2) unilateral grasping with a paw (beaver), (3) unilateral holding (ground squirrels), (4) various grip and digit postures (all species), (5) unilateral object removal from the mouth (gerbil), (6) bilateral thumb holding (squirrels), and (7) simultaneous holding/manipulation of two objects (squirrels). Only the guinea pig did not handle food with its paws, suggesting its behavior is regressive. The existence of a core pattern of paw and digit use in rodents suggests that skilled limb and paw movements originate at least with the common ancestors of the rodent, and likely the common ancestor to

  20. Changes in [3H]-PK 11195 and [3H]-8-OH-DPAT binding following forebrain ischaemia in the gerbil.

    PubMed Central

    Kenny, B. A.; MacKinnon, A. C.; Spedding, M.; Brown, C. M.

    1993-01-01

    1. A high density of [3H]-PK 11195 binding sites was present in gerbil cortical membranes (Bmax [3H]-PK 11195 1360 +/- 71 fmol mg-1 protein) in comparison to rat cortical membranes (254 +/- 21 fmol mg-1 protein). This effect was species-specific as similar findings were obtained with hippocampal membranes (Bmax 1430 +/- 111 fmol mg-1 protein in gerbil, compared to 196 +/- 31 in rat). 2. RO 5-4864, also a peripheral type benzodiazepine compound, displayed low affinity for the [3H]-PK 11195 site in the gerbil (pKi 6.57 +/- 0.02 and 6.70 +/- 0.12 in hippocampus and cortex respectively) compared to rat (pKi 8.16 +/- 0.07 and 8.48 +/- 0.02). Central benzodiazepine compounds, diazepam and flunitrazepam, also displayed this trend. 3. RO 5-4864 displaced [3H]-PK 11195 binding from gerbil and rat cortical membranes through a competitive interaction with Hill slopes close to unity. In both tissues, saturation isotherms of [3H]-PK 11195 binding indicated that the presence of RO 5-4864 caused changes in Kd without any effect on Bmax. In kinetic experiments, the presence of RO 5-4864 failed to modify the rate of dissociation of [3H]-PK 11195 from equilibrium in both rat and gerbil cortical membranes.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8395288

  1. Carotenoid profiles in provitamin A-containing fruits and vegetables affect the bioefficacy in Mongolian gerbils.

    PubMed

    Arscott, Sara A; Howe, Julie A; Davis, Christopher R; Tanumihardjo, Sherry A

    2010-07-01

    Fruits and vegetables are rich sources of provitamin A carotenoids. We evaluated the vitamin A (VA) bioefficacy of a whole foods supplement (WFS) and its constituent green vegetables (Study 1) and a variety of fruits with varying ratios of provitamin A carotenoids (Study 2) in VA-depleted Mongolian gerbils (n = 77/study). After feeding a VA-deficient diet for 4 and 6 weeks in Studies 1 and 2, respectively, customized diets, equalized for VA, were fed for 4 and 3 weeks, respectively. Both studies utilized negative and VA-positive control groups. In Study 1, liver VA was highest in the VA group (0.82 +/- 0.16 micromol/liver, P < 0.05), followed by brussels sprouts (0.50 +/- 0.15 micromol/liver), Betanat (beta-carotene from Blakeslea trispora) (0.50 +/- 0.12 micromol/liver) and spinach (0.47 +/- 0.09 micromol/liver) groups, which did not differ from baseline. The WFS (0.44 +/- 0.06 micromol/liver) and kale (0.43 +/- 0.14 micromol/liver) groups had lower liver VA than the baseline group (P < 0.05), but did not differ from the brussels sprouts, Betanat and spinach groups. In Study 2, liver VA was highest in the orange (0.67 +/- 0.18 micromol/liver), papaya (0.67 +/- 0.15 micromol/liver) and VA (0.66 +/- 0.14 micromol/liver) groups, followed by the mango (0.58 +/- 0.09 micromol/liver) and tangerine (0.55 +/- 0.15 micromol/liver) groups. These groups did not differ from baseline. The banana group (0.47 +/- 0.15 micromol/liver) was unable to maintain baseline stores of VA and did not differ from the control (0.46 +/- 0.13 mumol/liver). These fruits (except banana), vegetables and the WFS were able to prevent VA deficiency in Mongolian gerbils and could be an effective part of food-based interventions to support VA nutrition in developing countries and worldwide. PMID:20558838

  2. Biointeraction of sodium selenite and aflatoxin B/sub 1/ in the Mongolian gerbil

    SciTech Connect

    Lalor, J.H.; Llewellyn, G.C.

    1981-09-01

    The interaction of sodium selenite (Na/sub 2/SeO/sub 3/) and aflatoxin B/sub 1/ (AFB/sub 1/) was studied in 6-wk-old male Mongolian gerbils. Each of four groups of gerbils were fed one of the following diets during a 12-wk experimental period: control (commercial Chow), 5.0 ppm Na/sub 2/SeO/sub 3/, 12.8 ppm AFB/sub 1/, or 5.0 ppm Na/sub 2/SeO/sub 3/ + 12.8 ppm AFB/sub 1/. Animals receiving Na/sub 2/SeO/sub 3/ in the diet, alone and with AFB/sub 1/, had a significantly lower mean total weight gain during the experiment than did control animals. Animals receiving both compounds together displayed a very high level of physical activity compared to the three other groups. Blood analysis showed no change in total leukocytes, but the relative percentage of lymphocytes increased and the percentage of neutrophils decreased concurrently in the order: control < AFB/sub 1/ < Na/sub 2/SeO/sub 3/ + AFB/sub 1/ < Na/sub 2/SeO/sub 3/. A significant reduction in organ weight relative to body weight was observed in the liver, kidney, and lung of the animals fed AFB/sub 1/ alone but only in the liver of those fed both Na/sub 2/SeO/sub 3/ and AFB/sub 1/. No similar alterations were observed in the Na/sub 2/SeO/sub 3/ group. Histopathological examination revealed considerably less hepatic damage in animals fed Na/sub 2/SeO/sub 3/ with AFB/sub 1/ than in those receiving either compound alone. Renal and intestinal damage, however, was most severe in this double-treatment group. Hepatic protein analysis revealed two protein peaks in the Na/sub 2/SeO/sub 3/ + AFB/sub 1/ group that were absent in all other groups. It was concluded that these proteins may be selenoproteins directly or indirectly involved in the lower incidence of histopathological damage in this group.

  3. Novelty stress increases fecal pellet output in mongolian gerbils: effects of several drugs.

    PubMed

    Okano, Shiho; Nagaya, Hideaki; Inatomi, Nobuhiro

    2005-08-01

    Stress-induced colonic functional changes have been investigated mainly under conditions involving physical stress, like in the restraint stress model. In this study, we established a new stress-induced defecation model involving the placement of Mongolian gerbils in a novel environment (novelty stress) and determined the effects of several drugs on novelty stress-induced fecal pellet output. When animals kept in groups were placed individually in small cages, the fecal pellet output markedly increased, although the upper intestinal transit measured by charcoal method was not changed. The concentration of plasma adrenocorticotropic hormone was moderately but significantly increased by the novelty stress. Drugs reportedly effective for stress-induced defecation, like alosetron hydrochloride, atropine sulfate, and trimebutine maleate, inhibited both the novelty stress-induced increase in fecal pellet output and spontaneous defecation. In contrast, TAK-637, a tachykinin NK1-receptor antagonist, and diazepam inhibited the novelty stress induced defecation but did not inhibit spontaneous defecation. The present study indicated that novelty stress increases fecal pellet output without affecting the upper intestinal transit; this model may be useful for evaluating the effects of drugs on stress-stimulated colonic motility. PMID:16079466

  4. Periodotopy in the gerbil inferior colliculus: local clustering rather than a gradient map

    PubMed Central

    Schnupp, Jan W. H.; Garcia-Lazaro, Jose A.; Lesica, Nicholas A.

    2015-01-01

    Periodicities in sound waveforms are widespread, and shape important perceptual attributes of sound including rhythm and pitch. Previous studies have indicated that, in the inferior colliculus (IC), a key processing stage in the auditory midbrain, neurons tuned to different periodicities might be arranged along a periodotopic axis which runs approximately orthogonal to the tonotopic axis. Here we map out the topography of frequency and periodicity tuning in the IC of gerbils in unprecedented detail, using pure tones and different periodic sounds, including click trains, sinusoidally amplitude modulated (SAM) noise and iterated rippled noise. We found that while the tonotopic map exhibited a clear and highly reproducible gradient across all animals, periodotopic maps varied greatly across different types of periodic sound and from animal to animal. Furthermore, periodotopic gradients typically explained only about 10% of the variance in modulation tuning between recording sites. However, there was a strong local clustering of periodicity tuning at a spatial scale of ca. 0.5 mm, which also differed from animal to animal. PMID:26379508

  5. GABA and benzodiazepine receptors in the gerbil brain after transient ischemia: demonstration by quantitative receptor autoradiography

    SciTech Connect

    Onodera, H.; Sato, G.; Kogure, K.

    1987-02-01

    Quantitative receptor autoradiography was used to measure the binding of gamma-aminobutyric acid (GABA) and benzodiazepine receptors after ischemia by means of transient occlusion of bilateral common carotid arteries in the gerbil. (/sup 3/H)Muscimol was used to label the GABAA receptors and (/sup 3/H)flunitrazepam to label central type benzodiazepine receptors. In the superolateral convexities of the frontal cortices, (/sup 3/H)muscimol binding was increased in 60% of the animals killed 3 days after ischemia, and decreased in 67% of the animals killed 27 days after ischemia. Twenty-seven days after ischemia, (/sup 3/H)flunitrazepam binding in the substantia nigra pars reticulata increased to 252% of the control, though the increase in (/sup 3/H)muscimol binding was not significant. In the dorsolateral region of the caudate putamen, marked neuronal necrosis and depletion of both (/sup 3/H)muscimol and (/sup 3/H)flunitrazepam binding sites were observed 27 days after ischemia, the ventromedial region being left intact. In spite of the depletion of pyramidal cells in the CA1 region of the hippocampus, both (/sup 3/H)muscimol and (/sup 3/H)flunitrazepam binding sites were preserved 27 days after ischemia. Since our previous study revealed that adenosine A1 binding sites were depleted in the CA1 subfield of the hippocampus after ischemia correlating with neuronal damage, GABAA and benzodiazepine receptors may not be distributed predominantly on the pyramidal cells in the CA1 region.

  6. Periodotopy in the gerbil inferior colliculus: local clustering rather than a gradient map.

    PubMed

    Schnupp, Jan W H; Garcia-Lazaro, Jose A; Lesica, Nicholas A

    2015-01-01

    Periodicities in sound waveforms are widespread, and shape important perceptual attributes of sound including rhythm and pitch. Previous studies have indicated that, in the inferior colliculus (IC), a key processing stage in the auditory midbrain, neurons tuned to different periodicities might be arranged along a periodotopic axis which runs approximately orthogonal to the tonotopic axis. Here we map out the topography of frequency and periodicity tuning in the IC of gerbils in unprecedented detail, using pure tones and different periodic sounds, including click trains, sinusoidally amplitude modulated (SAM) noise and iterated rippled noise. We found that while the tonotopic map exhibited a clear and highly reproducible gradient across all animals, periodotopic maps varied greatly across different types of periodic sound and from animal to animal. Furthermore, periodotopic gradients typically explained only about 10% of the variance in modulation tuning between recording sites. However, there was a strong local clustering of periodicity tuning at a spatial scale of ca. 0.5 mm, which also differed from animal to animal. PMID:26379508

  7. Postnatal development of Mongolian gerbil female prostate: An immunohistochemical and 3D modeling study.

    PubMed

    Sanches, Bruno D A; Zani, Bruno C; Maldarine, Juliana S; Biancardi, Manoel F; Santos, Fernanda C A; Góes, Rejane M; Vilamaior, Patricia S L; Taboga, Sebastião R

    2016-05-01

    The development of the prostate in male rodents, which involves complex epithelial-mesenchymal interactions between the urogenital sinus epithelium (UGE) and the urogenital sinus mesenchyme (UGM), has been deeply studied. In females, however, this process is not very clear. In this study, the postnatal development of the prostate in female Mongolian gerbils employing three-dimensional (3D) reconstructions, histochemical, and immunohistochemical techniques was characterized. It was observed that prostatic branching and differentiation in females was induced by a single mesenchyme localized at a ventrolateral position, which was named as ventrolateral mesenchyme (VLM); furthermore, the canalization of solid buds began on the third postnatal day (P3) and the branching morphogenesis on P5. We observed secretions in the acini at the end of the first month, and, on P45, the acini were completely differentiated. The strong cell proliferation phase in the first week coincided with the mesenchymal expression of estrogen receptor 1 (ESR1). The expression of androgen receptor (AR) paralleled cell differentiation, and, on P30, immunolabelling with p63 was restricted to basal cells. This study serves as a baseline parameter for future research on disruptions that could affect the development of the female prostate. Microsc. Res. Tech. 79:438-446, 2016. © 2016 Wiley Periodicals, Inc. PMID:26971884

  8. Molecular analysis of isolates of the cestode Rodentolepis nana from the great gerbil, Rhombomys opimus.

    PubMed

    Mirjalali, H; Kia, E B; Kamranrashani, B; Hajjaran, H; Sharifdini, M

    2016-03-01

    Rodentolepis nana (syn. Hymenolepis nana) is a cyclophyllidean zoonotic enteric parasite with worldwide distribution. In humans, it is more prevalent in children, especially in temperate zones. A morphologically similar species of R. nana occurs in different rodents, including gerbils. In the present study molecular characterization of five isolates of R. nana from Rhombomys opimus in the Golestan Province (n= 2) and Razavi Khorasan Province (n= 3), both in north-eastern Iran, were analysed. After DNA extraction, the internal transcribed spacer 2 (ITS2) region of the R. nana isolates was amplified and sequenced, and genetic variation was analysed. Accordingly, two isolates from the Razavi Khorasan Province showed ITS2 signatures that differed from the isolates from the Golestan Province. The third isolate from Razavi Khorasan did not reveal these specific signatures, but exhibited sparse nucleotide polymorphisms in the ITS2 sequence. The ITS gene is conserved, and variation in this fragment could be an interesting subject for further inspection of existing variation in the genome of R. nana, among different domestic and wildlife host species and from different areas. PMID:25779770

  9. Neuroprotection and reduced gliosis by atomoxetine pretreatment in a gerbil model of transient cerebral ischemia.

    PubMed

    Park, Joon Ha; Shin, Bich Na; Chen, Bai Hui; Kim, In Hye; Ahn, Ji Hyeon; Cho, Jeong-Hwi; Tae, Hyun-Jin; Lee, Jae-Chul; Lee, Choong-Hyun; Kim, Young-Myeong; Lee, Yun Lyul; Kim, Sung Koo; Won, Moo-Ho

    2015-12-15

    Atomoxetine (ATX) is a non-stimulant selective norepinephrine reuptake inhibitor that is widely used for the treatment of attention-deficit/hyperactivity disorder (ADHD). In this study, we firstly examined neuroprotective effects of pre- or post-treatment with 15 and 30 mg/kg ATX against ischemic damage in the gerbil hippocampal cornus ammonis 1 (CA1) region subjected to 5 min of transient cerebral ischemia using cresyl violet staining, neuronal nuclei immunohistochemistry and Fluoro-J B histofluorescence staining. We found that only pre-treatment with 30 mg/kg ATX protected CA1 pyramidal neurons from ischemic insult. In addition, pre-treatment with 30 mg/kg ATX, which had neuroprotective effect against ischemic damage, distinctly attenuated the activation of astrocytes and microglia in the ischemic CA1 region compared with the vehicle-treated ischemia group by glial fibrillary acidic protein (for astrocytes) and ionized calcium-binding adapter molecule 1 (for microglia) immunohistochemistry. In brief, our present results indicate that ATX has neuroprotective effect against transient cerebral ischemic insult and that the neuroprotective effect of ATX may be closely associated with attenuated glial activation. PMID:26671145

  10. Neuroprotective activity of chlormethiazole following transient forebrain ischaemia in the gerbil.

    PubMed Central

    Cross, A. J.; Jones, J. A.; Baldwin, H. A.; Green, A. R.

    1991-01-01

    1. The effect of chlormethiazole, and other drugs which potentiate gamma-aminobutyric acid (GABA) function on delayed neuronal death in the hippocampus has been examined in the gerbil. 2. Chlormethiazole (100 mg kg-1, i.p.) and two other drugs previously reported to be neuroprotective (dizocilpine, 3 mg kg-1, i.p. and ifenprodil, 4 mg kg-1, i.p.) were all found to prevent neurodegeneration of CA1/CA2 neurones in the hippocampus when given 30 min before a 5 min episode of bilateral carotid artery occlusion. 3. Chlormethiazole (100 mg kg-1) was neuroprotective when given up to 3 h, after the ischaemic episode. 4. Given 1 h after the cartoid artery occlusion, chlormethiazole produced significant protection against hippocampal neurodegeneration at a dose of 50 mg kg-1, but not at 25 mg kg-1. 5. Phenobarbitone (100 mg kg-1, i.p.) and Saffan (alphaxalone, 45 mg kg-1 plus alphadalone, 15 mg kg-1, i.p.) were not protective when given 1 h after the ischaemic episode while pentobarbitone (30 mg kg-1, i.p.) had a modest protective effect. 6. Evidence is presented to show that neither the operating procedure nor the chlormethiazole administration lowered rectal or cerebral temperature. 7. The data suggest that chlormethiazole may be a useful treatment in the prevention of neurodegeneration following stroke or cardiac arrest. Images Figure 1 PMID:1797307

  11. Electrical filtering in gerbil isolated type I semicircular canal hair cells

    NASA Technical Reports Server (NTRS)

    Rennie, K. J.; Ricci, A. J.; Correia, M. J.

    1996-01-01

    1. Membrane potential responses of dissociated gerbil type I semicircular canal hair cells to current injections in whole cell current-clamp have been measured. The input resistance of type I cells was 21.4 +/- 14.3 (SD) M omega, (n = 25). Around the zero-current potential (Vz = -66.6 +/- 9.3 mV, n = 25), pulsed current injections (from approximately -200 to 750 pA) produced only small-amplitude, pulse-like changes in membrane potential. 2. Injecting constant current to hyperpolarize the membrane to around -100 mV resulted in a approximately 10-fold increase in membrane resistance. Current pulses superimposed on this constant hyperpolarization produced larger and more complex membrane potential changes. Depolarizing currents > or = 200 pA caused a rapid transient peak voltage before a plateau. 3. Membrane voltage was able to faithfully follow sine-wave current injections around Vz over the range 1-1,000 Hz with < 25% attenuation at 1 kHz. A previously described K conductance, IKI, which is active at Vz, produces the low input resistance and frequency response. This was confirmed by pharmacologically blocking IKI. This conductance, present in type I cells but not type II hair cells, would appear to confer on type I cells a lower gain, but a much broader bandwidth at Vz, than seen in type II cells.

  12. Relationship of neural and otoacoustic emission thresholds during endocochlear potential development in the gerbil

    NASA Astrophysics Data System (ADS)

    Mills, David M.

    2004-08-01

    Distortion product otoacoustic emissions and auditory brainstem responses (ABRs) were measured in neonatal gerbils at three ages: at 15-16 days after birth (dab), near the onset of hearing when the endocochlear potential (EP) is known to be still immature; at 22 dab, when the EP first reaches mature levels; and at 30 dab. Comparing individual 15-16 dab animals to the 22 dab group, ABR threshold changes were typically larger than those for cubic distortion tone (CDT, 2f1-f2) emission thresholds which were, in turn, larger than those for the simple difference tone (DT, f2-f1). In contrast, from 22 to 30 dab there were no important changes in CDT or DT emission thresholds. Observed threshold-change relationships were very similar to those found in differential diagnosis investigations, where the EP was experimentally decreased using a chronic furosemide application. Therefore, most of the change in cochlear function over the two week period studied could be attributed to the maturation of EP during the first week. Model calculations further show that relative changes in CDT and DT emission thresholds are compatible with a movement of the operating point of the cochlear amplifier toward its symmetrical ``central'' point as the EP reaches mature levels.

  13. Neuroprotective effects of tadalafil on gerbil dopaminergic neurons following cerebral ischemia.

    PubMed

    Kim, Kwang Taek; Chung, Kyung Jin; Lee, Han Sae; Ko, Il Gyu; Kim, Chang Ju; Na, Yong Gil; Kim, Khae Hawn

    2013-03-15

    Impairment of dopamine function, which is known to have major effects on behaviors and cognition, is one of the main problems associated with cerebral ischemia. Tadalafil, a long-acting phosphodiesterase type-5 inhibitor, is known to ameliorate neurologic impairment induced by brain injury, but not in dopaminergic regions. We investigated the neuroprotective effects of treatment with tadalafil on cyclic guanosine monophosphate level and dopamine function following cerebral ischemia. Forty adult Mongolian gerbils were randomly and evenly divided into five groups (n = 8 in each group): Sham-operation group, cerebral ischemia-induced and 0, 0.1, 1, and 10 mg/kg tadalafil-treated groups, respectively. Tadalafil dissolved in distilled water was administered orally for 7 consecutive days, starting 1 day after surgery. Cyclic guanosine monophosphate assay and immunohistochemistry were performed for thyrosine hydroxylase expression and western blot analysis for dopamine D2 receptor expression. A decrease in cyclic guanosine monophosphate level following cerebral ischemia was found with an increase in thyrosine hydroxylase activity and a decrease in dopamine D2 receptor expression in the striatum and substantia nigra region. However, treatment with tadalafil increased cyclic guanosine monophosphate expression, suppressed thyrosine hydroxylase expression and increased dopamine D2 receptor expression in the striatum and substantia nigra region in a dose-dependent manner. Tadalafil might ameliorate cerebral ischemia-induced dopaminergic neuron injury. Therefore, tadalafil has the potential as a new neuroprotective treatment strategy for cerebral ischemic injury. PMID:25206715

  14. Effects of a 2X gravity environment on the ultrastructure of the gerbil parathyroid gland

    NASA Technical Reports Server (NTRS)

    Sannes, P. L.; Hayes, T. G.

    1975-01-01

    A number of studies concerning the effects of hypergravity on bone have shown increases in bone mass or bone dimensions. Correlative studies, which could provide clues to the mechanism for such a response, have been lacking. The purpose of the present study was to evaluate the ultrastructure of parathyroid glands of Mongolian gerbils exposed to a continuous 2 X gravity force for 60 d. It was found that the experimental animals had parathyroid glands which had a greater percentage of chief cells in the active stage of their secretory cycle when compared with control animals. This result was interpreted to indicate an increase in parathyroid gland secretory activity and, hence, an increase in parathyroid hormone release. It was suggested that increased parathyroid secretory activity was necessary to maintain serum calcium levels of hypergravity animals within normal limits. Cellular forms resembling water clear cells and highly compact, degenerating cells were described in experimental animals but not in controls. Areas suggestive of cellular dissolution and disorganization were also reported in experimental parathyroids.

  15. Reducing individual differences in the external-ear transfer functions of the Mongolian gerbil

    NASA Astrophysics Data System (ADS)

    Maki, Katuhiro; Furukawa, Shigeto

    2005-10-01

    This study examines individual differences in the directional transfer functions (DTFs), the directional components of head-related transfer functions of gerbils, and seeks a method for reducing these differences. The difference between the DTFs of a given animal pair was quantified by the intersubject spectral difference (ISSD), which is the variance in the difference spectra of DTFs for frequencies between 5 and 45 kHz and for 361 source directions. An attempt was made to reduce the ISSD by scaling the DTFs of one animal in frequency and/or rotating the DTFs along the source coordinate sphere. The ISSD was reduced by a median of 12% after optimal frequency scaling alone, by a median of 19% after optimal spatial rotation alone, and by a median of 36% after simultaneous frequency scaling and spatial rotation. The optimal scaling factor (OSF) and the optimal coordinate rotation (OCR) correlated strongly with differences in head width and pinna angles (i.e., pinna inclination around the vertical and front-back axes), respectively. Thus, linear equations were derived to estimate the OSF and OCR from these anatomical measurements. The ISSD could be reduced by a median of 22% based on the estimated OSF and OCR.

  16. Using a third tone to probe the physiological generation site of distortion product otoacoustic emissions in gerbil

    NASA Astrophysics Data System (ADS)

    Dong, Wei

    2015-12-01

    The generation of distortion product otoacoustic emissions (DPOAEs) has been summarized using a two-mechanism theory consisting of nonlinear distortion and linear coherent reflection. However, the precise generation site in the cochlea is still unclear. The current study in gerbils used a third tone in different cochlear regions to probe the cochlear origin site of DPOAEs. DPOAEs and their intracochlear sources, distortion products (DPs), were simultaneously measured. Our results suggest that the major generation site of DPOAEs evoked by an f2/f1 ratio of 1.25 extends basal to the primary f2 place, which is consistent with notions about the location of the cochlear amplifier.

  17. NK1 receptor antagonism lowers occupancy requirement for antidepressant-like effects of SSRIs in the gerbil forced swim test.

    PubMed

    Lelas, Snjezana; Li, Yu-Wen; Wallace-Boone, Tanya L; Taber, Matthew T; Newton, Amy E; Pieschl, Rick L; Davis, Carl D; Molski, Thaddeus F; Newberry, Kimberly S; Parker, Michael F; Gillman, Kevin W; Bronson, Joanne J; Macor, John E; Lodge, Nicholas J

    2013-10-01

    The known interactions between the serotonergic and neurokinin systems suggest that serotonin reuptake inhibitor (SSRIs) efficacy may be improved by neurokinin-1 receptor (NK1R) antagonism. In the current studies combination of a subeffective dose of an SSRI (0.3 mg/kg fluoxetine or 0.03 mg/kg citalopram) with a subeffective dose of an NK1R antagonist (0.3 mg/kg aprepitant or 1 mg/kg CP-122,721) produced efficacy in the gerbil forced swim test (FST). Serotonin transporter (SERT) occupancy produced by 1 mg/kg fluoxetine (lowest efficacious dose) was 52 ± 5% and was reduced to 29 ± 4% at 0.3 mg/kg, a dose that was efficacious in combination with 0.3 mg/kg aprepitant or 1 mg/kg CP-122,721; the corresponding NK1R occupancies were 79 ± 4% and 61 ± 4% for aprepitant and CP-122,721, respectively. For citalopram, SERT occupancy at the lowest efficacious dose (0.1 mg/kg) was 50 ± 4% and was reduced to 20 ± 5% at 0.03 mg/kg, a dose that was efficacious when combined with aprepitant (0.3 mg/kg). Aprepitant (10 mg/kg) augmented the serotonin elevation produced by fluoxetine (1 or 10 mg/kg) in the gerbil prefrontal cortex; i.e. NK1R antagonism can modulate serotonin responses. A novel orally-available dual-acting NK1R antagonist/SERT inhibitor BMS-795176 is described; gerbil Ki = 1.4 and 1 nM at NK1R and SERT, respectively. BMS-795176 was efficacious in the gerbil FST; efficacy was observed with 35 ± 3% SERT occupancy and 73 ± 3% NK1R occupancy. The interaction between NK1R antagonism and SERT inhibition to lower the SERT occupancy required for antidepressant-like efficacy suggests that BMS-795176 has the potential to improve efficacy with a reduction in SSRI-associated side effects. PMID:23770339

  18. [Importance of Shaw's Jird Meriones shawii within the trophic components of the Barn Owl Tyto alba in steppic areas of Algeria].

    PubMed

    Sekour, Makhlouf; Souttou, Karim; Guerzou, Ahlem; Benbouzid, Noureddine; Guezoul, Omar; Ababsa, Labed; Denys, Christiane; Doumandji, Salaheddine

    2014-06-01

    The study of the diet of the Barn Owl in two steppic regions (M'Sila and Djelfa) located in the Algerian highlands is based on the analysis of the pellets of rejections collected in six stations. The analysis of 706 pellets resulting from the various stations made it possible to count 1380 individuals, represented by seven classes, 12 orders, 32 families, and 76 species of preys. The mammals are consumed with variable abundance rates between 59.1 % and 90.0 % whose predominance is assigned to the rodents (relative abundance: AR > 58 %). The latter constitute the most advantageous preys in biomass (61.4 ≤ B % ≤ 99.2). The most consumed prey is Meriones shawii, with variable rates between 31.9 % and 76.6 %. Generally, Tyto alba presents a diversified diet in the majority of the stations (0.69 ≤ E ≤ 0.76), except the station of Ain El-Hadjel (E = 0.35), with a low diversity and dominance of M. shawii (AR = 76.6 %). PMID:24961561

  19. Seasonal expression of KiSS-1 and the pituitary gonadotropins LHβ and FSHβ in adult male Libyan jird (Meriones libycus).

    PubMed

    Boufermes, R; Richard, N; Le Moguen, K; Amirat, Z; Khammar, F; Kottler, M L

    2014-06-10

    The molecular mechanisms operating on a seasonal time-scale and regulating functions such as reproduction are poorly understood in animals living in desert environments. Kisspeptin, the product of the KiSS-1 gene, plays a critical role in control of the hypothalamic-pituitary-gonad axis that orchestrates the reproductive system in vertebrates. We report a sequence analysis of KiSS-1 and the pituitary luteinising hormone-beta (LHβ) and follicle-stimulating hormone-beta (FSHβ) in the Libyan jird (Meriones libycus), a seasonal breeding rodent that is sexually active during spring and quiescent in fall. We also assessed gene expression by quantitative real-time reverse transcription-polymerase chain reaction during the non-breeding and breeding seasons. The KiSS-1 cDNA sequence analysis showed high homology between M. libycus and all other rodents (94%) and humans (92%). KiSS-1 expression was higher during the breeding season than that during the non-breeding season. In contrast, LHβ and FSHβ expression levels were higher during the non-breeding season in autumn and varied in an opposite manner with testicular, seminal vesicle weights and plasma testosterone levels. Our results extend the role for KiSS-1 in activating the HPG axis in this desert rodent in its natural biotope by relaying environmental cues as in other seasonal non-desert rodent models. PMID:24786546

  20. Predicting binaural responses from monaural responses in the gerbil medial superior olive.

    PubMed

    Plauška, Andrius; Borst, J Gerard; van der Heijden, Marcel

    2016-06-01

    Accurate sound source localization of low-frequency sounds in the horizontal plane depends critically on the comparison of arrival times at both ears. A specialized brainstem circuit containing the principal neurons of the medial superior olive (MSO) is dedicated to this comparison. MSO neurons are innervated by segregated inputs from both ears. The coincident arrival of excitatory inputs from both ears is thought to trigger action potentials, with differences in internal delays creating a unique sensitivity to interaural time differences (ITDs) for each cell. How the inputs from both ears are integrated by the MSO neurons is still debated. Using juxtacellular recordings, we tested to what extent MSO neurons from anesthetized Mongolian gerbils function as simple cross-correlators of their bilateral inputs. From the measured subthreshold responses to monaural wideband stimuli we predicted the rate-ITD functions obtained from the same MSO neuron, which have a damped oscillatory shape. The rate of the oscillations and the position of the peaks and troughs were accurately predicted. The amplitude ratio between dominant and secondary peaks of the rate-ITD function, captured in the width of its envelope, was not always exactly reproduced. This minor imperfection pointed to the methodological limitation of using a linear representation of the monaural inputs, which disregards any temporal sharpening occurring in the cochlear nucleus. The successful prediction of the major aspects of rate-ITD curves supports a simple scheme in which the ITD sensitivity of MSO neurons is realized by the coincidence detection of excitatory monaural inputs. PMID:27009164

  1. Morphological characteristics of eosinophilic neuronal death after transient unilateral forebrain ischemia in Mongolian gerbils.

    PubMed

    Shen, Yanling; Wang, Zongli; Li, Fuying; Sun, Liyuan

    2016-06-01

    Various types of eosinophilic neurons (ENs) are found in the post-ischemic brain. The aim of the present study was to elucidate the temporal and spatial profile of ENs, the expression of TUNEL staining and ultrastructural characteristics in the core and peripheral regions of the cortex post-ischemia. Unilateral forebrain ischemia was induced in Mongolian gerbils by transient common carotid artery occlusions, and the brains from 3 h to 2 weeks post-ischemia were prepared for morphometric, electron microscopy (EM) and TUNEL staining of the ENs. Light microscopy showed that ENs with minimally abnormal nuclei and swollen cell bodies appeared at 3 h in the ischemic core and at 12 h in the periphery. Thereafter, ENs with pyknosis and irregular atrophic cytoplasm peaked at 12 h, pyknosis with scant cytoplasm peaked at 4 days, and TUNEL-positive staining was observed in the ischemic core. In the ischemic periphery, ENs had slightly atrophic cytoplasm and sequentially developed pyknosis, karyorrhexis and karyolysis over 1 week. These cells were also positive for TUNEL. In EM, severe organelle dilation and vacuolization preceded chromatin fragmentation in the ischemic core, while chromatin fragmentation and homogenization were the vital characteristics in the ischemic periphery. There might be two region-dependent pathways for EN changes in the post-ischemic brain: pyknosis with cytoplasmic shrinkage in the core and nuclear disintegration with slightly atrophic cytoplasm in the periphery. These pathways were comparable to necrosis and proceeded from non-classical apoptosis to necrosis, respectively. PMID:26607557

  2. Progesterone as a morphological regulatory factor of the male and female gerbil prostate

    PubMed Central

    Fochi, Ricardo A; Santos, Fernanda C A; Goes, Rejane M; Taboga, Sebastião R

    2013-01-01

    Testosterone (T) and oestrogen are the main active steroid hormones in the male and female reproductive system respectively. In female rodents progesterone (P4), together with testosterone and oestrogen, has an essential role in the regulation of the oestrous cycle, which influences the prostate physiology through their oscillations. In this work we investigated how the male and female prostate gland of Mongolian gerbils responds to surgical castration at the start of puberty and what are the effects of T, oestradiol (E2) and P4 replacement, using both quantitative and qualitative methods. We also examined the location of the main steroid receptors present in the prostate. In the castrated animals of both sexes an intense glandular regression, along with disorganization of the stromal compartment, and abundant hyperplasia was observed. The replacement of P4 secured a mild recovery of the glandular morphology, inducing the growth of secretory cells and restoring the androgen receptor (AR) cells. The administration of P4 and E2 eliminated epithelial hyperplasia and intensified gland hypertrophy, favouring the emergence of prostatic intraepithelial neoplasia (PIN). In animals treated with T and P4, even though there are some inflammatory foci and other lesions, the prostate gland revealed morphology closer to that of control animals. In summary, through the administration of P4, we could demonstrate that this hormone has anabolic characteristics, promoting hyperplasia and hypertrophy, mainly in the epithelial compartment. When combined with E2 and T, there is an accentuation of glandular hypertrophy that interrupts the development of hyperplasia and ensures the presence of a less dysplastic glandular morphology. PMID:24205795

  3. Correlation of Fos expression and circling asymmetry during gerbil vestibular compensation

    NASA Technical Reports Server (NTRS)

    Kaufman, G. D.; Shinder, M. E.; Perachio, A. A.

    1999-01-01

    Vestibular compensation is a central nervous system process resulting in recovery of functional movement and control following a unilateral vestibular lesion. Small pressure injections of phosphorothioate 20mer oligonucleotides were used to probe the role of the Fos transcription protein during vestibular compensation in the gerbil brainstem. During isoflurane gas anesthesia, antisense probes against the c-fos mRNA sequence were injected into the medial vestibular and prepositus nuclei unilaterally prior to a unilateral surgical labyrinthectomy. Anionic dyes, which did not interact with the oligonucleotides, were used to mark the injection site and help determine the extent of diffusion. The antiFos oligonucleotide injections reduced Fos expression at the injection site in neurons which normally express Fos after the lesion, and also affected circling behavior induced by hemilabyrinthectomy. With both ipsilateral and contralateral medial vestibular and prepositus nuclei injections, less ipsilateral and more contralateral circling was noted in animals injected with antiFos injections as compared to non-injected controls. The degree of change in these behaviors was dependent upon the side of the injection. Histologically, antiFos injections reduced the number of Fos immunolabeled neurons around the injection site, and increased Fos expression contralaterally. The correlation of the number of neurons with Fos expression to turning behavior was stronger for contralateral versus ipsilateral turns, and for neurons in the caudal and ipsilateral sub-regions of the medial vestibular and prepositus nuclei. The results are discussed in terms of neuronal firing activity versus translational activity based on the asymmetrical expression of the Fos inducible transcription factor in the medial vestibular and prepositus nuclei. Although ubiquitous in the brain, transcription factors like Fos can serve localized and specific roles in sensory-specific adaptive stimuli. Antisense

  4. Photodynamic therapy of otitis media in-vitro and in-vivo using gerbil

    NASA Astrophysics Data System (ADS)

    Rhee, Chung-Ku; Kwon, Pil Seung; Ahn, Jin Chul; Chung, Phil Sang; Ge, Ruifeng

    2008-02-01

    The aim of this study was to evaluate antibacterial effects of PDT on common bacteria causing otitis media with effusion (OME). In vitro study was carried out using a hematoporphyrin derivative sensitizer (photogem) and 632 nm diode laser on H. influenzae, M. catarrhalis, and S. pneumoniae. One ml of each bacterial suspension was incubated for 3 hours and various concentrations of photogem were administered into the suspension. The suspensions were irradiated with 632 diode laser (15 J/cm2). The presence of colony forming units of the bacteria was examined, microscopic structures of bacteria were examined by TEM, and cytometry of bacteria was performed. The PDT was effective in killing all 3 kinds of bacteria. TEM showed damaged bacterial cell membrane and cytoplasmic structures and the flow cytometry showed lower number of viable bacteria in PDT group comparing to the control group. In vivo PDT study was performed using gerbil. S. pneumoniae or H. influenzae was injected into bullae. Photogem was injected into bullae in 2 days by when OME was developed and transcanal irradiation of 632 nm diode laser (90 J) was performed with a fiber perforated through an ear drum into a middle ear cavity and bulla. Four days after PDT, middle ear and bulla were washed with DPBS and the washed DPBS was cultured. The presence of bacterial colonies was examined. PDT was effective in killing S. pneumoniae in 87 % of the infected bullae with OME while it was effective to eradicate H. influenzae in 50 % of the infected bullae with OME. The results of these studies demonstrated that PDT may be effective to treat otitis media. It may have clinical implication to treat otitis media that is resistant to antibiotic therapy.

  5. Functional maturation of the exocytotic machinery at gerbil hair cell ribbon synapses

    PubMed Central

    Johnson, Stuart L; Franz, Christoph; Knipper, Marlies; Marcotti, Walter

    2009-01-01

    Auditory afferent fibre activity in mammals relies on neurotransmission at hair cell ribbon synapses. Developmental changes in the Ca2+ sensitivity of the synaptic machinery allow inner hair cells (IHCs), the primary auditory receptors, to encode Ca2+ action potentials (APs) during pre-hearing stages and graded receptor potentials in adult animals. However, little is known about the time course of these changes or whether the kinetic properties of exocytosis differ as a function of IHC position along the immature cochlea. Furthermore, the role of afferent transmission in outer hair cells (OHCs) is not understood. Calcium currents and exocytosis (measured as membrane capacitance changes: ΔCm) were measured with whole-cell recordings from immature gerbil hair cells using near-physiological conditions. The kinetics, vesicle pool depletion and Ca2+ coupling of exocytosis were similar in apical and basal immature IHCs. This could indicate that possible differences in AP activity along the immature cochlea do not require synaptic specialization. Neurotransmission in IHCs became mature from postnatal day 20 (P20), although changes in its Ca2+ dependence occurred at P9–P12 in basal and P12–P15 in apical cells. OHCs showed a smaller ΔCm than IHCs that was reflected by fewer active zones in OHCs. Otoferlin, the proposed Ca2+ sensor in cochlear hair cells, was similarly distributed in both cell types despite the high-order exocytotic Ca2+ dependence in IHCs and the near-linear relation in OHCs. The results presented here provide a comprehensive study of the function and development of hair cell ribbon synapses. PMID:19237422

  6. Inhibitory properties underlying non-monotonic input-output relationship in low-frequency spherical bushy neurons of the gerbil

    PubMed Central

    Kuenzel, Thomas; Nerlich, Jana; Wagner, Hermann; Rübsamen, Rudolf; Milenkovic, Ivan

    2015-01-01

    Spherical bushy cells (SBCs) of the anteroventral cochlear nucleus (AVCN) receive input from large excitatory auditory nerve (AN) terminals, the endbulbs of Held, and mixed glycinergic/GABAergic inhibitory inputs. The latter have sufficient potency to block action potential firing in vivo and in slice recordings. However, it is not clear how well the data from slice recordings match the inhibition in the intact brain and how it contributes to complex phenomena such as non-monotonic rate-level functions (RLF). Therefore, we determined the input-output relationship of a model SBC with simulated endbulb inputs and a dynamic inhibitory conductance constrained by recordings in brain slice preparations of hearing gerbils. Event arrival times from in vivo single-unit recordings in gerbils, where 70% of SBC showed non-monotonic RLF, were used as input for the model. Model output RLFs systematically changed from monotonic to non-monotonic shape with increasing strength of tonic inhibition. A limited range of inhibitory synaptic properties consistent with the slice data generated a good match between the model and recorded RLF. Moreover, tonic inhibition elevated the action potentials (AP) threshold and improved the temporal precision of output functions in a SBC model with phase-dependent input conductance. We conclude that activity-dependent, summating inhibition contributes to high temporal precision of SBC spiking by filtering out weak and poorly timed EPSP. Moreover, inhibitory parameters determined in slice recordings provide a good estimate of inhibitory mechanisms apparently active in vivo. PMID:25873864

  7. Valeriana officinalis Extracts Ameliorate Neuronal Damage by Suppressing Lipid Peroxidation in the Gerbil Hippocampus Following Transient Cerebral Ischemia.

    PubMed

    Yoo, Dae Young; Jung, Hyo Young; Nam, Sung Min; Kim, Jong Whi; Choi, Jung Hoon; Kwak, Youn-Gil; Yoo, Miyoung; Lee, Sanghee; Yoon, Yeo Sung; Hwang, In Koo

    2015-06-01

    As a medicinal plant, the roots of Valeriana officinalis have been used as a sedative and tranquilizer. In the present study, we evaluated the neuroprotective effects of valerian root extracts (VE) on the hippocampal CA1 region of gerbils after 5 min of transient cerebral ischemia. Gerbils were administered VE orally once a day for 3 weeks, subjected to ischemia/reperfusion injury, and continued on VE for 3 weeks. The administration of 100 mg/kg VE (VE100 group) significantly reduced the ischemia-induced spontaneous motor hyperactivity 1 day after ischemia/reperfusion. Four days after ischemia/reperfusion, animals treated with VE showed abundant cresyl violet-positive neurons in the hippocampal CA1 region when compared to the vehicle or 25 mg/kg VE-treated groups. In addition, the VE treatment markedly decreased microglial activation in the hippocampal CA1 region 4 days after ischemia. Compared to the other groups, the VE100 group showed the lowest level of lipid peroxidation during the first 24 h after ischemia/reperfusion. In summary, the findings in this study suggest that pretreatment with VE has protective effects against ischemic injury in the hippocampal pyramidal neurons by decreasing microglial activation and lipid peroxidation. PMID:25785762

  8. [Cytological and cytogenetic studies of cells of Mongolian gerbils' retinal epithelium and marrow following 12-day space flight].

    PubMed

    Vorozhtsova, S V; Abrosimova, A N; Fedorenko, B S; Rakov, D V

    2011-01-01

    The paper report the results of studying mitotic activity and cytogenetic disorders in marrow and retinal epithelium cells of Mongolian gerbils in 21 - 23 hrs. of landing space apparatus Foton-M3, and the animals of synchronous and vivarium controls. Cells of the space flown gerbils displayed a statistically significant (p < 0.05) gain in the ratio of mitosis prophases and metaphases to the sum of ana- and telophases (1.7 +/- 0.3 and 2 +/- 0.1, respectively) as compared to these parameters in the synchronous and vivarium controls, where the ratio made up 0.6 +/- 0.1 and 0.7 +/- 0.1, respectively. Frequency of aberrant mytoses in the form of bridges was increased equally in both types of cells. Patterns of chromosome damages occurred in flight infer that the major portion of changes was not due to chromosome breakage but adhesion and ensuing wrong disjunction. These results seem to have been caused by acute g-stress to organism during re-entry and return from micro-g to the normal gravity. PMID:21675195

  9. Saccule contribution to immediate early gene induction in the gerbil brainstem with posterior canal galvanic or hypergravity stimulation

    NASA Technical Reports Server (NTRS)

    Marshburn, T. H.; Kaufman, G. D.; Purcell, I. M.; Perachio, A. A.

    1997-01-01

    Immunolabeling patterns of the immediate early gene-related protein Fos in the gerbil brainstem were studied following stimulation of the sacculus by both hypergravity and galvanic stimulation. Head-restrained, alert animals were exposed to a prolonged (1 h) inertial vector of 2 G (19.6 m/s2) head acceleration directed in a dorso-ventral head axis to maximally stimulate the sacculus. Fos-defined immunoreactivity was quantified, and the results compared to a control group. The hypergravity stimulus produced Fos immunolabeling in the dorsomedial cell column (dmcc) of the inferior olive independently of other subnuclei. Similar dmcc labeling was induced by a 30 min galvanic stimulus of up to -100 microA applied through a stimulating electrode placed unilaterally on the bony labyrinth overlying the posterior canal (PC). The pattern of vestibular afferent firing activity induced by this galvanic stimulus was quantified in anesthetized gerbils by simultaneously recording from Scarpa's ganglion. Only saccular and PC afferent neurons exhibited increases in average firing rates of 200-300%, suggesting a pattern of current spread involving only PC and saccular afferent neurons at this level of stimulation. These results suggest that alteration in saccular afferent firing rates are sufficient to induce Fos-defined genomic activation of the dmcc, and lend further evidence to the existence of a functional vestibulo-olivary-cerebellar pathway of adaptation to novel gravito-inertial environments.

  10. In vitro development of Strongylus edentatus to the fourth larval stage with notes on Strongylus vulgaris and Strongylus equinus.

    PubMed

    Farrar, R G; Klei, T R

    1985-08-01

    Strongylus edentatus was successfully cultured in vitro to the fourth larval stage (L4). Some growth continued for periods of 40-50 days at which time reductions in viability were observed in some of the culture systems tested. Various combinations of media, sera, buffers and organ explant cultures were tested. All cultures were incubated at 37 C in an atmosphere of 95% air and 5% CO2. Larvae underwent growth and differentiation to the L4 in all medium-serum combinations with and without organ explant cultures. Development and growth did occur but viability was reduced to insignificant levels in media without serum or cells. Optimal growth, differentiation, and longevity were observed in bicarbonate buffered RPMI-1640 containing 10% fetal calf serum and gerbil (Meriones unguiculatus) cecum explant cultures. Observations indicated that Strongylus vulgaris and Strongylus equinus also developed to the L4 stage using similar techniques. However, viability of S. vulgaris L4 was markedly limited. Specific morphological changes marked phases of development of S. edentatus, categorized as early, middle and late third stage, third molt and early fourth stage. Strongylus equinus appeared to follow the same developmental pattern in vitro as S. edentatus. Distinct differences in morphological features during differentiation were observed between S. edentatus and S. vulgaris. PMID:4032151

  11. Identification and characterization of Helicobacter pylori genes essential for gastric colonization.

    PubMed

    Kavermann, Holger; Burns, Brendan P; Angermuller, Katrin; Odenbreit, Stefan; Fischer, Wolfgang; Melchers, Klaus; Haas, Rainer

    2003-04-01

    Helicobacter pylori causes one of the most common, chronic bacterial infections and is a primary cause of severe gastric disorders. To unravel the bacterial factors necessary for the process of gastric colonization and pathogenesis, signature tagged mutagenesis (STM) was adapted to H. pylori. The Mongolian gerbil (Meriones unguiculatus) was used as model system to screen a set of 960 STM mutants. This resulted in 47 H. pylori genes, assigned to 9 different functional categories, representing a set of biological functions absolutely essential for gastric colonization, as verified and quantified for many mutants by competition experiments. Identification of previously known colonization factors, such as the urease and motility functions validated this method, but also novel and several hypothetical genes were found. Interestingly, a secreted collagenase, encoded by hp0169, could be identified and functionally verified as a new essential virulence factor for H. pylori stomach colonization. Furthermore, comB4, encoding a putative ATPase being part of a DNA transformation-associated type IV transport system of H. pylori was found to be absolutely essential for colonization, but natural transformation competence was apparently not the essential function. Thus, this first systematic STM application identified a set of previously unknown H. pylori colonization factors and may help to potentiate the development of novel therapies against gastric Helicobacter infections. PMID:12668646

  12. Cryptosporidium scrofarum n. sp. (Apicomplexa: Cryptosporidiidae) in domestic pigs (Sus scrofa)

    PubMed Central

    Kváč, Martin; Kestřánová, Michaela; Pinková, Martina; Květoňová, Dana; Kalinová, Jana; Wagnerová, Pavla; Kotková, Michaela; Vítovec, Jiří; Ditrich, Oleg; McEvoy, John; Stenger, Brianna; Sak, Bohumil

    2012-01-01

    We describe the morphological, biological, and molecular characteristics of Cryptosporidium pig genotype II and propose the species name Cryptosporidium scrofarum n. sp. to reflect its prevalence in adult pigs worldwide. Oocysts of C. scrofarum are morphologically indistinguishable from C. parvum, measuring 4.81–5.96 µm (mean = 5.16) × 4.23–5.29 µm (mean = 4.83) with a length to width ratio of 1.07 ± 0.06 (n = 400). Oocysts of C. scrofarum obtained from a naturally infected pig were infectious for 8-week-old pigs but not 4-week-old pigs. The prepatent period in 8-week-old Cryptosporidium-naive pigs was 4–6 days and the patent period was longer than 30 days. The infection intensity of C. scrofarum in pigs was generally low, in the range 250-4000 oocysts per gram of faeces. Infected pigs showed no clinical signs of cryptosporidiosis and no pathology was detected. Cryptosporidium scrofarum was not infectious for adult SCID mice, adult BALB c mice, Mongolian gerbils (Meriones unguiculatus), southern multimammate mice (Mastomys coucha), yellow-necked mice (Apodemus flavicollis), or guinea pigs (Cavia porcellus). Phylogenetic analyses based on Small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. scrofarum is genetically distinct from all known Cryptosporidium species. PMID:23021264

  13. Determination of 5-methylcytosine from plant DNA by high-performance liquid chromatography.

    PubMed

    Wagner, I; Capesius, I

    1981-06-26

    The relative amounts of the five nucleosides (deoxycytidine, 5-methyldeoxycytidine, deoxyadenosine, deoxyguanosine and thymidine) in the DNA of nine plant species, one plant satellite DNA, and one animal species were determined by high performance liquid chromatography. The method allows the clean separation of the nucleosides from 10 microgram samples with 15 min. The following values for the proportion of methylated cytosines among all cytosines were obtained: Lobularia maritima 18.5%, Nicotiana tabacum 32.6%, Pisum sativum 23.2%, Rhinanthus minor 29.2%, Sinapsis alba 12.2%, Vicia faba 30.5%, Viscum album 23.2%, Cymbidium pumilum 18.8%, Cymbidium pumilum AT-rich satellite DNA 15.8%, Triticum aestivum 22.4%. DNA of an animal, the gerbil, Meriones unguiculatus, had a methylation percentage of 3.1%. An estimate of the GC content based on the buoyant density of DNA tends to be lower than the actual value, an estimate based on the melting temperature tends to be higher. This supports the finding by other authors that DNA methylation decreases the buoyant density and may increase the melting temperature at high m5C concentration. PMID:7272310

  14. Development of the stomach worm, Obeliscoides cuniculi (Graybill), in lagomorphs, woodchucks and small rodents.

    PubMed

    Measures, L N; Anderson, R C

    1983-07-01

    The parasitic development of Obeliscoides cuniculi multistriatus Measures and Anderson, 1983 was studied in New Zealand white rabbits (Oryctolagus cuniculus). Third-stage larvae exsheathed within 24 hr. The third molt occurred 3 days and the fourth 8-11 days post-infection. All worms were fifth stage 14 days post-infection. Males were mature at 16 days and copulation occurred in 15-16 days. Females were gravid at 18 days. The prepatent period was 16-22 days. The patent period was 61-118 days and males lived longer than females. All stages were found in the mucosa except the fifth which was found lying on the mucosal surface within a layer of mucus. Petechiae were the only lesions seen in experimentally infected rabbits. Patent infections of O. c. multistriatus were established experimentally in infected woodchucks (Marmota monax), snowshoe hares (Lepus americanus) and cottontail rabbits (Sylvilagus floridanus). Patent infections of O. c. cuniculi were established experimentally in snowshoe hares. Patent infections of O. c. multistriatus did not appear in experimentally infected HPB white (Swiss Webster) mice (Mus musculus). Wistar rats (Rattus norvegicus), H.O.R.F1 Syrian hamsters (Mesocricetus auratus), H.O.R.F1 smooth-haired guinea pigs (Cavia porcellus) and H.O.R.F1 gerbils (Meriones unguiculatus). PMID:6644921

  15. Developmental basis of limb length in rodents: evidence for multiple divisions of labor in mechanisms of endochondral bone growth.

    PubMed

    Rolian, Campbell

    2008-01-01

    Mammals are remarkably diverse in limb lengths and proportions, but the number and kind of developmental mechanisms that contribute to length differences between limb bones remain largely unknown. Intra- and interspecific differences in bone length could result from variations in the cellular processes of endochondral bone growth, creating differences in rates of chondrocyte proliferation or hypertrophy, variation in the shape and size of chondrocytes, differences in the number of chondrocytes in precursor populations and throughout growth, or a combination of these mechanisms. To address these questions, this study compared cellular mechanisms of endochondral bone growth in cross-sectional ontogenetic series of the appendicular skeleton of two rodent species: the mouse (Mus musculus) and Mongolian gerbil (Meriones unguiculatus). Results indicate that multiple cellular processes of endochondral bone growth contribute to phenotypic differences in limb bone length. The data also suggest that separate developmental processes contribute to intraspecific length differences in proximal versus distal limb bones, and that these proximo-distal mechanisms are distinct from mechanisms that contribute to interspecific differences in limb bone length related to body size. These developmental "divisions of labor" are hypothesized to be important features of vertebrate limb development that allow (1) morphology in the autopods to evolve independently of the proximal limb skeleton, and (2) adaptive changes in limb proportions related to locomotion to evolve independently of evolutionary changes in body size. PMID:18184354

  16. Cryptosporidium scrofarum n. sp. (Apicomplexa: Cryptosporidiidae) in domestic pigs (Sus scrofa).

    PubMed

    Kváč, Martin; Kestřánová, Michaela; Pinková, Martina; Květoňová, Dana; Kalinová, Jana; Wagnerová, Pavla; Kotková, Michaela; Vítovec, Jiří; Ditrich, Oleg; McEvoy, John; Stenger, Brianna; Sak, Bohumil

    2013-01-31

    We describe the morphological, biological, and molecular characteristics of Cryptosporidium pig genotype II and propose the species name Cryptosporidium scrofarum n. sp. to reflect its prevalence in adult pigs worldwide. Oocysts of C. scrofarum are morphologically indistinguishable from C. parvum, measuring 4.81-5.96 μm (mean=5.16)×4.23-5.29 μm (mean=4.83) with a length to width ratio of 1.07±0.06 (n=400). Oocysts of C. scrofarum obtained from a naturally infected pig were infectious for 8-week-old pigs but not 4-week-old pigs. The prepatent period in 8-week-old Cryptosporidium-naive pigs was 4-6 days and the patent period was longer than 30 days. The infection intensity of C. scrofarum in pigs was generally low, in the range 250-4000 oocysts per gram of feces. Infected pigs showed no clinical signs of cryptosporidiosis and no pathology was detected. Cryptosporidium scrofarum was not infectious for adult SCID mice, adult BALB/c mice, Mongolian gerbils (Meriones unguiculatus), southern multimammate mice (Mastomys coucha), yellow-necked mice (Apodemus flavicollis), or guinea pigs (Cavia porcellus). Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. scrofarum is genetically distinct from all known Cryptosporidium species. PMID:23021264

  17. Cryptosporidium erinacei n. sp. (Apicomplexa: Cryptosporidiidae) in hedgehogs.

    PubMed

    Kváč, Martin; Hofmannová, Lada; Hlásková, Lenka; Květoňová, Dana; Vítovec, Jiří; McEvoy, John; Sak, Bohumil

    2014-03-17

    The morphological, biological, and molecular characteristics of Cryptosporidium hedgehog genotype are described, and the species name Cryptosporidium erinacei n. sp. is proposed to reflect its specificity for hedgehogs under natural and experimental conditions. Oocysts of C. erinacei are morphologically indistinguishable from Cryptosporidium parvum, measuring 4.5-5.8 μm (mean=4.9 μm) × 4.0-4.8 μm (mean=4.4 μm) with a length to width ratio of 1.13 (1.02-1.35) (n=100). Oocysts of C. erinacei obtained from a naturally infected European hedgehog (Erinaceus europaeus) were infectious for naïve 8-week-old four-toed hedgehogs (Atelerix albiventris); the prepatent period was 4-5 days post infection (DPI) and the patent period was longer than 20 days. C. erinacei was not infectious for 8-week-old SCID and BALB/c mice (Mus musculus), Mongolian gerbils (Meriones unguiculatus), or golden hamsters (Mesocricetus auratus). Phylogenetic analyses based on small subunit rRNA, 60 kDa glycoprotein, actin, Cryptosporidium oocyst wall protein, thrombospondin-related adhesive protein of Cryptosporidium-1, and heat shock protein 70 gene sequences revealed that C. erinacei is genetically distinct from previously described Cryptosporidium species. PMID:24529828

  18. Characterizing Wave Propagation in the Organ of Corti with Stroboscopic Imaging

    NASA Astrophysics Data System (ADS)

    Zosuls, Aleks; Rupprecht, Laura C.; Mountain, David C.

    2011-11-01

    Here we present the results from a new high-frequency mechanical stimulation system that was designed to provide more precise local excitation and motion sensing of the organ of Corti (OC/BM complex). It is based on mechanical tissue excitation via a small vibrating probe and measurement using stroboscopic video microscopy. The system is currently capable of measuring sub-micrometer motion at frequencies from DC to 60 kHz. Measurements were performed on excised Mongolian gerbil (Meriones unguiculatus) cochleae. The underside of the BM was mechanically stimulated in the direction normal to the membrane with a 20 μm diameter glass probe. Data was collected at multiple focal planes from the BM to the tectorial membrane in order to capture motion for cellular and extracellular structures. For this study, inner hair cell hair bundles and basilar membrane collagen fiber bundle regions of interest were selected and displacements quantified using a cross-correlation technique. Displacement magnitude and phase was measured as a function of distance from the probe and a function of stimulus frequency. At certain frequencies both magnitudes and phases decreased with distance from the probe in a manner that suggests that both direct longitudinal coupling and wave propagation were contributing to the responses.

  19. Delayed hippocampal neuronal death in young gerbil following transient global cerebral ischemia is related to higher and longer-term expression of p63 in the ischemic hippocampus

    PubMed Central

    Bae, Eun Joo; Chen, Bai Hui; Yan, Bing Chun; Shin, Bich Na; Cho, Jeong Hwi; Kim, In Hye; Ahn, Ji Hyeon; Lee, Jae Chul; Tae, Hyun-Jin; Hong, Seongkweon; Kim, Dong Won; Cho, Jun Hwi; Lee, Yun Lyul; Won, Moo-Ho; Park, Joon Ha

    2015-01-01

    The tumor suppressor p63 is one of p53 family members and plays a vital role as a regulator of neuronal apoptosis in the development of the nervous system. However, the role of p63 in mature neuronal death has not been addressed yet. In this study, we first compared ischemia-induced effects on p63 expression in the hippocampal regions (CA1–3) between the young and adult gerbils subjected to 5 minutes of transient global cerebral ischemia. Neuronal death in the hippocampal CA1 region of young gerbils was significantly slow compared with that in the adult gerbils after transient global cerebral ischemia. p63 immunoreactivity in the hippocampal CA1 pyramidal neurons in the sham-operated young group was significantly low compared with that in the sham-operated adult group. p63 immunoreactivity was apparently changed in ischemic hippocampal CA1 pyramidal neurons in both ischemia-operated young and adult groups. In the ischemia-operated adult groups, p63 immunoreactivity in the hippocampal CA1 pyramidal neurons was significantly decreased at 4 days post-ischemia; however, p63 immunoreactivity in the ischemia-operated young group was significantly higher than that in the ischemia-operated adult group. At 7 days post-ischemia, p63 immunoreactivity was decreased in the hippocampal CA1 pyramidal neurons in both ischemia-operated young and adult groups. Change patterns of p63 level in the hippocampal CA1 region of adult and young gerbils after ischemic damage were similar to those observed in the immunohistochemical results. These findings indicate that higher and longer-term expression of p63 in the hippocampal CA1 region of the young gerbils after ischemia/reperfusion may be related to more delayed neuronal death compared to that in the adults. PMID:26199612

  20. Convergent properties of vestibular-related brain stem neurons in the gerbil

    NASA Technical Reports Server (NTRS)

    Kaufman, G. D.; Shinder, M. E.; Perachio, A. A.

    2000-01-01

    Three classes of vestibular-related neurons were found in and near the prepositus and medial vestibular nuclei of alert or decerebrate gerbils, those responding to: horizontal translational motion, horizontal head rotation, or both. Their distribution ratios were 1:2:2, respectively. Many cells responsive to translational motion exhibited spatiotemporal characteristics with both response gain and phase varying as a function of the stimulus vector angle. Rotationally sensitive neurons were distributed as Type I, II, or III responses (sensitive to ipsilateral, contralateral, or both directions, respectively) in the ratios of 4:6:1. Four tested factors shaped the response dynamics of the sampled neurons: canal-otolith convergence, oculomotor-related activity, rotational Type (I or II), and the phase of the maximum response. Type I nonconvergent cells displayed increasing gains with increasing rotational stimulus frequency (0.1-2.0 Hz, 60 degrees /s), whereas Type II neurons with convergent inputs had response gains that markedly decreased with increasing translational stimulus frequency (0.25-2.0 Hz, +/-0.1 g). Type I convergent and Type II nonconvergent neurons exhibited essentially flat gains across the stimulus frequency range. Oculomotor-related activity was noted in 30% of the cells across all functional types, appearing as burst/pause discharge patterns related to the fast phase of nystagmus during head rotation. Oculomotor-related activity was correlated with enhanced dynamic range compared with the same category that had no oculomotor-related response. Finally, responses that were in-phase with head velocity during rotation exhibited greater gains with stimulus frequency increments than neurons with out-of-phase responses. In contrast, for translational motion, neurons out of phase with head acceleration exhibited low-pass characteristics, whereas in-phase neurons did not. Data from decerebrate preparations revealed that although similar response types could

  1. Three-dimensional analysis of vestibular efferent neurons innervating semicircular canals of the gerbil

    NASA Technical Reports Server (NTRS)

    Purcell, I. M.; Perachio, A. A.

    1997-01-01

    Anterograde labeling techniques were used to examine peripheral innervation patterns of vestibular efferent neurons in the crista ampullares of the gerbil. Vestibular efferent neurons were labeled by extracellular injections of biocytin or biotinylated dextran amine into the contralateral or ipsilateral dorsal subgroup of efferent cell bodies (group e) located dorsolateral to the facial nerve genu. Anterogradely labeled efferent terminal field varicosities consist mainly of boutons en passant with fewer of the terminal type. The bouton swellings are located predominately in apposition to the basolateral borders of the afferent calyces and type II hair cells, but several boutons were identified close to the hair cell apical border on both types. Three-dimensional reconstruction and morphological analysis of the terminal fields from these cells located in the sensory neuroepithelium of the anterior, horizontal, and posterior cristae were performed. We show that efferent neurons densely innervate each end organ in widespread terminal fields. Subepithelial bifurcations of parent axons were minimal, with extensive collateralization occurring after the axons penetrated the basement membrane of the neuroepithelium. Axonal branching ranged between the 6th and 27th orders and terminal field collecting area far exceeds that of the peripheral terminals of primary afferent neurons. The terminal fields of the efferent neurons display three morphologically heterogeneous types: central, peripheral, and planum. All cell types possess terminal fields displaying a high degree of anisotropy with orientations typically parallel to or within +/-45 degrees of the longitudinal axis if the crista. Terminal fields of the central and planum zones predominately project medially toward the transverse axis from the more laterally located penetration of the basement membrane by the parent axon. Peripheral zone terminal fields extend predominately toward the planum semilunatum. The innervation

  2. Finite-Element Modelling of the Response of the Gerbil Middle Ear to Sound.

    PubMed

    Maftoon, Nima; Funnell, W Robert J; Daniel, Sam J; Decraemer, Willem F

    2015-10-01

    We present a finite-element model of the gerbil middle ear that, using a set of baseline parameters based primarily on a priori estimates from the literature, generates responses that are comparable with responses we measured in vivo using multi-point vibrometry and with those measured by other groups. We investigated the similarity of numerous features (umbo, pars-flaccida and pars-tensa displacement magnitudes, the resonance frequency and break-up frequency, etc.) in the experimental responses with corresponding ones in the model responses, as opposed to simply computing frequency-by-frequency differences between experimental and model responses. The umbo response of the model is within the range of variability seen in the experimental data in terms of the low-frequency (i.e., well below the middle-ear resonance) magnitude and phase, the main resonance frequency and magnitude, and the roll-off slope and irregularities in the response above the resonance frequency, but is somewhat high for frequencies above the resonance frequency. At low frequencies, the ossicular axis of rotation of the model appears to correspond to the anatomical axis but the behaviour is more complex at high frequencies (i.e., above the pars-tensa break-up). The behaviour of the pars tensa in the model is similar to what is observed experimentally in terms of magnitudes, phases, the break-up frequency of the spatial vibration pattern, and the bandwidths of the high-frequency response features. A sensitivity analysis showed that the parameters that have the strongest effects on the model results are the Young's modulus, thickness and density of the pars tensa; the Young's modulus of the stapedial annular ligament; and the Young's modulus and density of the malleus. Displacements of the tympanic membrane and manubrium and the low-frequency displacement of the stapes did not show large changes when the material properties of the incus, stapes, incudomallear joint, incudostapedial joint, and

  3. Accumulation of heavy metals and As in liver, hair, femur, and lung of Persian jird (Meriones persicus) in Darreh Zereshk copper mine, Iran.

    PubMed

    Khazaee, Manoochehr; Hamidian, Amir Hossein; Alizadeh Shabani, Afshin; Ashrafi, Sohrab; Mirjalili, Seyyed Ali Ashghar; Esmaeilzadeh, Esmat

    2016-02-01

    Rodents frequently serve as bioindicator to monitor the quality of the environment. Concentrations of 11 elements (Cd, Co, Ti, Fe, Mn, Cu, Sb, As, Sr, Ni, and Cr) were investigated and compared in liver, hair, femur, and lung of the Persian jird (Meriones persicus) from Darreh Zereshk copper mine, Iran. Metals were determined in different tissues of 39 individuals of Persian jird, collected by snap trap in 2014 from five areas of Darreh Zereshk copper mine. Samples were prepared by wet digestion method, and the contents of elements were analyzed with ICP-OES (VARIAN, 725-ES) instrument. Cadmium, Sb, and Co were below the limit of detection, and Mn and As were found only in hair and liver tissues. We detected the highest concentration of Cu, As, Ti, Fe, Mn, Cr, and Ni in hair in comparison with other tissues. Significant higher levels of Ti in femur and hair; Fe in liver and hair; Mn in liver; As in hair; Sr in lung; Cr in lung, hair, femur, and liver; Cu in femur; and Ni in liver and lung tissues were observed in females. Nearly all element concentrations in the tissues of Persian jird from flotation site, Darreh Zereshk and Hasan Abad villages and leaching site (mining areas) were higher than those from tailing dump site (reference site). We found the highest concentrations of As in liver and hair; Ni and Cr in liver, hair, and lung; and Sr in lung and hair tissues of Persian jird in leaching site. We tried to specify the status of elements before fully exploitation of Darreh Zereshk copper mine by using bioindicator species. Based on our achievements, initial activities did not strongly pollute the surrounded environment of the mine. The high abundance of Persian jird as well as their several proper features makes them a suitable species for biomonitoring programs especially for further studies will be performed after full exploitation of Darreh Zereshk copper mine. PMID:26498968

  4. First Report on Isolation and Characterization of Leishmania major from Meriones hurrianae (Rodentia: Gerbillidae) of A Rural Cutaneous leishmaniasis Focus in South-Eastern Iran

    PubMed Central

    Kassiri, Hamid; Naddaf, Saied Reza; Javadian, Ezat–Aldin; Mohebali, Mehdi

    2013-01-01

    Background Zoonotic Cutaneous Leishmaniasis (ZCL) is an endemic health problem in many rural areas of Iran, with doubled number of incidences over the last decade. Different species of rodents serve as natural reservoir host for ZCL. The disease is considered as a major health problem in rural areas of Mirjaveh, Chabahar, and Konarak Counties of Sistan va Baluchistan Province. Objectives This study describes the identity of Leishmania species, isolated from Meriones hurrianae from Chabahar County using RAPD-PCR methodology. Materials and Methods Rodents were entrapped by live traps baited with roasted walnut, tomato, and cucumber during spring and summer. All rodents were identified based on external features including fur color, ears characteristics, tail length, hind feet, body measurements, and internal features of teeth and cranium. Giemsa-stained impressions from rodents’ ears were examined for amastigotes microscopically. The samples from infected rodents were cultured in NNN+LIT medium and then the harvested parasites at the stationary phase were subjected to DNA extraction followed by amplification with RAPD-PCR. Results All the 28 entrapped animals were identified as M. hurrianae. Five animals showed to harbor Leishmania parasite by microscopy. Leishmania DNA isolated from five M. hurrianae produced distinctive bands of L. major with four primers. However, the products that were amplified with primers AB1-07, 327, and 329 were stable and reproducible. This is the first report on the isolation and identification of L. major from M. hurrianae from Iran. Conclusions Regarding infection rate of 17.8%, M. hurrianae seems to play the major role in the maintenance and transmission of disease to humans in this area. PMID:24616787

  5. Neuroprotection of Chrysanthemum indicum Linne against cerebral ischemia/reperfusion injury by anti-inflammatory effect in gerbils.

    PubMed

    Yoo, Ki-Yeon; Kim, In Hye; Cho, Jeong-Hwi; Ahn, Ji Hyeon; Park, Joon Ha; Lee, Jae-Chul; Tae, Hyun-Jin; Kim, Dae Won; Kim, Jong-Dai; Hong, Seongkweon; Won, Moo-Ho; Kang, Il Jun

    2016-02-01

    In this study, we tried to verify the neuroprotective effect of Chrysanthemum indicum Linne (CIL) extract, which has been used as a botanical drug in East Asia, against ischemic damage and to explore the underlying mechanism involving the anti-inflammatory approach. A gerbil was given CIL extract for 7 consecutive days followed by bilateral carotid artery occlusion to make a cerebral ischemia/reperfusion model. Then, we found that CIL extracts protected pyramidal neurons in the hippocampal CA1 region (CA1) from ischemic damage using neuronal nucleus immunohistochemistry and Fluoro-Jade B histofluorescence. Accordingly, interleukin-13 immunoreactivities in the CA1 pyramidal neurons of CIL-pretreated animals were maintained or increased after cerebral ischemia/reperfusion. These findings indicate that the pre-treatment of CIL can attenuate neuronal damage/death in the brain after cerebral ischemia/reperfusion via an anti-inflammatory approach. PMID:27073380

  6. Neuroprotection of Chrysanthemum indicum Linne against cerebral ischemia/reperfusion injury by anti-inflammatory effect in gerbils

    PubMed Central

    Yoo, Ki-Yeon; Kim, In Hye; Cho, Jeong-Hwi; Ahn, Ji Hyeon; Park, Joon Ha; Lee, Jae-Chul; Tae, Hyun-Jin; Kim, Dae Won; Kim, Jong-Dai; Hong, Seongkweon; Won, Moo-Ho; Kang, Il Jun

    2016-01-01

    In this study, we tried to verify the neuroprotective effect of Chrysanthemum indicum Linne (CIL) extract, which has been used as a botanical drug in East Asia, against ischemic damage and to explore the underlying mechanism involving the anti-inflammatory approach. A gerbil was given CIL extract for 7 consecutive days followed by bilateral carotid artery occlusion to make a cerebral ischemia/reperfusion model. Then, we found that CIL extracts protected pyramidal neurons in the hippocampal CA1 region (CA1) from ischemic damage using neuronal nucleus immunohistochemistry and Fluoro-Jade B histofluorescence. Accordingly, interleukin-13 immunoreactivities in the CA1 pyramidal neurons of CIL-pretreated animals were maintained or increased after cerebral ischemia/reperfusion. These findings indicate that the pre-treatment of CIL can attenuate neuronal damage/death in the brain after cerebral ischemia/reperfusion via an anti-inflammatory approach. PMID:27073380

  7. Neuroprotective effects of lamotrigine in global ischemia in gerbils. A histological, in vivo microdialysis and behavioral study.

    PubMed

    Shuaib, A; Mahmood, R H; Wishart, T; Kanthan, R; Murabit, M A; Ijaz, S; Miyashita, H; Howlett, W

    1995-12-01

    A sudden surge in the release of glutamate is currently believed to be an important initiating step in neuronal damage due to an ischemic insult. In this experiment, we tested the efficacy of neuroprotection with lamotrigine, a novel antiepileptic drug that blocks voltage gated sodium channels and inhibits the ischemia-induced release of glutamate in the gerbil forebrain model of cerebral ischemia. The medication was administered 30 min before and 30 min after the insult in two groups of animals. Histological assessment of neuronal damage was evaluated at 7 and 28 days after the ischemic insult. Animals evaluated at 28 days also underwent behavioral testing. Microdialysis was used in the same model to study the response of ischemia-induced glutamate in saline treated controls versus animals treated with lamotrigine 20 min before the insult. There was highly significant neuronal protection in animals who were treated with lamotrigine either before or after the insult. Protection was seen both at 7 and 28 days after the insult. Behavioral testing also showed significantly better recovery in both sets of animals in comparison to the saline-treated group. Microdialysis confirmed a significant attenuation of the ischemia-induced glutamate surge when compared to the saline-treated animals. Our morphological, behavioral and microdialysis experiments show that lamotrigine offers significant neuroprotection from the effects of transient forebrain ischemia in gerbils. Neuroprotection with post-ischemic therapy probably depends on preserving the capacity of the sodium/calcium exchanger to reduce intracellular calcium concentrations or persistent 'toxicity' of glutamate in the reperfusion period on the already 'primed' injured neurons. These concepts need further study. PMID:8846077

  8. Long-term observation of neuronal degeneration and microgliosis in the gerbil dentate gyrus after transient cerebral ischemia.

    PubMed

    Ahn, Ji Hyeon; Shin, Bich Na; Park, Joon Ha; Kim, In Hye; Cho, Jeong Hwi; Chen, BaiHui; Lee, Tae-Kyeong; Tae, Hyun-Jin; Lee, Jae-Chul; Cho, Jun Hwi; Kang, Il Jun; Kim, Young-Myeong; Lee, Yun Lyul; Won, Moo-Ho; Seo, Jeong Yeol

    2016-04-15

    Ischemic insults in the central nervous system evoke activation of microglia. In this study, we investigated long-term changes of neuronal damage and microglial activation in the gerbil dentate gyrus for 60 days after transient cerebral ischemia using immunohistochemistry and western blot. Neuronal damage or death was hardly found in the dentate gyrus after transient ischemia using cresyl violet staining and NeuN immunohistochemistry; however, neuronal degeneration was detected in the polymorphic layer of the dentate gyrus using Fluoro-Jade (F-J) B staining. F-J B-positive cells were significantly increased after ischemia-reperfusion (I-R) and peaked at 3 days post-ischemia, thereafter, F-J B-positive cells were decreased in a time-dependent manner and shown until 30 days post-ischemia; no F-J B-positive cells were observed 60 days after I-R. On the other hand, Iba-1-immunoreactive microglia were hypertrophied after I-R, and numbers of Iba-1-immunoreactive microglia were significantly increased along with the neuronal degeneration and highest 7 days after I-R, thereafter, numbers of Iba-1-immunoreactive microglia were decreased with time, although microglia activation lasted up to 60 days after I-R. In addition, Iba-1 protein level in the dentate gyrus after I-R was changed like immunohistochemical change. Our results, in brief, indicate that transient ischemia-induced neuronal degeneration in the dentate gyrus is maintained for about 30 days after I-R and that microglial activation lasts up to, at least, 60 days after I-R in the gerbil dentate gyrus after transient cerebral ischemia. PMID:27000214

  9. Long-term dynamics of fecal corticosterone in male great gerbils (Rhombomys opimus Licht.): effects of environment and social demography.

    PubMed

    Rogovin, Konstantin A; Randall, Jan A; Kolosova, Irina E; Moshkin, Mikhail P

    2008-01-01

    We examined the relationship among seasonal characteristics of climate, food, and population demography (social structure) and fecal corticosterone (CORT) concentrations over 6 yr in adult males of an arid-adapted species, the great gerbil (Rhombomys opimus Licht., Gerbillidae, Rodentia), as a measure of chronic stress in high, low, and recovering population densities. Results showed yearly differences in the seasonal means of CORT, with the highest concentrations in the year of the highest population density. Analysis of year-specific relationships revealed a positive correlation between mean CORT and total precipitation in January and February and a negative correlation with precipitation in March. In the beginning of spring, when gerbils were in maximum reproductive effort, CORT correlated positively with the saturation of burrow systems and with the number of adult females with an adult male. A linear stepwise regression of CORT in individual males in spring seasons of all 6 yr combined after removal of year effects revealed that CORT depended positively on the number of females associated with a single male but negatively on the abundance of annual herbs. Disappearance of adult males was not related to CORT in most cases. We found no correlation between overall mortality from season to season and mean CORT in either spring (March-May) or fall. In fact, we found a highly negative correlation between mean CORT and the proportion of disappeared males at the beginning of spring. Only at the high population density when cases of probable catastrophic mortality of all adults in the group were excluded was CORT of individual males related positively to their disappearance during the summer drought. Our results suggest that desert rodents with irregular population fluctuations are more sensitive to suppression by external factors than by density-dependent mortality mediated by stress. The favorable feeding and climatic conditions may have compensated for density

  10. Acetylcholinesterase activity in the sexually dimorphic area of the gerbil brain: sex differences and influences of adult gonadal steroids.

    PubMed

    Commins, D; Yahr, P

    1984-03-20

    The morphology of the medial preoptic area-anterior hypothalamus (MPOA-AH) of gerbils is sexually dimorphic and influenced by adult gonadal hormones. This research shows that the distribution of (MPOA-AH) cells that synthesize acetylcholinesterase (AChE) and the activity of AChE within the MPOA-AH are also sexually dimorphic and hormone sensitive. Adult male and female gerbils were gonadectomized, gonadectomized and implanted subcutaneously with testosterone (T), or sham operated 4-8 weeks before sacrifice. Coronal sections through the sexually dimorphic area (SDA) of the MPOA-AH were stained for AChE. Planimeter measurements of camera lucida drawings showed that the total volume of the SDA is similar in the two sexes, but the proportion of the SDA that stains darkly and/or stands out clearly from the surround (dark volume) is larger in males. Optical density readings also indicated that AChE staining is darker in the male SDA. Gonadectomy decreases staining intensity in both sexes and reduces total SDA volume. Dark volume decreases more than 50%. Testosterone treatment reverses all effects of gonadectomy, although hormonal influences are smaller in females than in males. There were no sex differences or hormonal influences on AChE staining lateral to the SDA. The pars compacta of the male SDA was essentially devoid of AChE, indicating that this cell group is distinct from the rest of the SDA. It also shrinks after castration unless the males receive T. Histochemical changes in the SDA may be related to hormonal control of scent marking, a form of communication in this species. PMID:6715576

  11. Cooking enhances but the degree of ripeness does not affect provitamin A carotenoid bioavailability from bananas in Mongolian gerbils.

    PubMed

    Bresnahan, Kara A; Arscott, Sara A; Khanna, Harjeet; Arinaitwe, Geofrey; Dale, James; Tushemereirwe, Wilberforce; Mondloch, Stephanie; Tanumihardjo, Jacob P; De Moura, Fabiana F; Tanumihardjo, Sherry A

    2012-12-01

    Banana is a staple crop in many regions where vitamin A deficiency is prevalent, making it a target for provitamin A biofortification. However, matrix effects may limit provitamin A bioavailability from bananas. The retinol bioefficacies of unripe and ripe bananas (study 1A), unripe high-provitamin A bananas (study 1B), and raw and cooked bananas (study 2) were determined in retinol-depleted Mongolian gerbils (n = 97/study) using positive and negative controls. After feeding a retinol-deficient diet for 6 and 4 wk in studies 1 and 2, respectively, customized diets containing 60, 30, or 15% banana were fed for 17 and 13 d, respectively. In study 1A, the hepatic retinol of the 60% ripe Cavendish group (0.52 ± 0.13 μmol retinol/liver) differed from baseline (0.65 ± 0.15 μmol retinol/liver) and was higher than the negative control group (0.39 ± 0.16 μmol retinol/liver; P < 0.0065). In study 1B, no groups differed from baseline (0.65 ± 0.15 μmol retinol/liver; P = 0.20). In study 2, the 60% raw Butobe group (0.68 ± 0.17 μmol retinol/liver) differed from the 60% cooked Butobe group (0.87 ± 0.24 μmol retinol/liver); neither group differed from baseline (0.80 ± 0.27 μmol retinol/liver; P < 0.0001). Total liver retinol was higher in the groups fed cooked bananas than in those fed raw (P = 0.0027). Body weights did not differ even though gerbils ate more green, ripe, and raw bananas than cooked, suggesting a greater indigestible component. In conclusion, thermal processing, but not ripening, improves the retinol bioefficacy of bananas. Food matrix modification affects carotenoid bioavailability from provitamin A biofortification targets. PMID:23096010

  12. Dynamic changes of NADH fluorescence images and NADH content during spreading depression in the cerebral cortex of gerbils.

    PubMed

    Hashimoto, M; Takeda, Y; Sato, T; Kawahara, H; Nagano, O; Hirakawa, M

    2000-07-28

    To elucidate the changes in the mitochondrial redox state during spreading depression (SD), tissue NADH content was measured in 20 anesthetized gerbils by the enzymatic cycling assay in a small cortical region (0.30+/-0.07 mg) where the direct-current (DC)-potential was measured. Sequential imaging of NADH fluorescence with a CCD camera and continuous monitoring of DC-potential and regional CBF were also performed in another 5 gerbils. Biphasic fluorescence waves propagating at the rate of 3 mm/min were observed using the CCD camera. An initial narrow (1.6+/-0.4 mm) wave, which showed a modest increase in fluorescence (108+/-6.4%), was observed simultaneously with the onset of negative DC-deflection. During depolarization, CBF was unchanged and tissue NADH content increased to 25.3+/-7.9 micromol/kg brain, which was higher than the value in the sham-control (11.0+/-2.5 micromol/kg brain). At 30 s after the deflection, a subsequent wide (7.0+/-2.1 mm) wave, which showed a moderate decrease in fluorescence (87.1+/-5.7%), was observed simultaneously with the increase in CBF and repolarization in DC-potential. Then NADH fluorescence recovered along with normalization of CBF at 152.2+/-38.6 s after the onset of DC-deflection. Tissue NADH concentration sampled at 120 s after the deflection was 11.6+/-4.6 micromol/kg brain. Since NADH fluorescence is absorbed by hemoglobin, the initial increase and subsequent decrease in fluorescence seem to have been induced by increases in NADH content and CBF, respectively. These findings indicate that the mitochondrial redox state transiently inclines to the reduction side synchronous to the onset of DC-deflection and that it normalizes within 120 s after deflection. PMID:10924711

  13. Inhibitory effect of nordihydroguaiaretic acid, a plant lignan, on Helicobacter pylori-associated gastric carcinogenesis in Mongolian gerbils.

    PubMed

    Toyoda, Takeshi; Tsukamoto, Tetsuya; Mizoshita, Tsutomu; Nishibe, Sansei; Deyama, Takeshi; Takenaka, Yoshiharu; Hirano, Naoki; Tanaka, Harunari; Takasu, Shinji; Ban, Hisayo; Kumagai, Toshiko; Inada, Ken-Ichi; Utsunomiya, Hirotoshi; Tatematsu, Masae

    2007-11-01

    Recent epidemiological studies have demonstrated that consumption of certain natural products can lower cancer risk in humans. For example, plant-derived lignans have been shown to exert chemopreventive effects against cancer in vitro and in vivo. In the present study, the effects of three such lignans, termed arctiin, arctigenin, and nordihydroguaiaretic acid (NDGA), on the proliferation of Helicobacter pylori and the prevention of H. pylori-associated gastric cancer were investigated in Mongolian gerbils. To examine the effects of arctigenin and NDGA on stomach carcinogenesis, specific pathogen-free male, 5-week-old gerbils were infected with H. pylori, administered 10 p.p.m. N-methyl-N-nitrosourea in their drinking water and fed diets containing various concentrations of lignans until they were killed after 52 weeks. At a dietary level of 0.25%, NDGA significantly decreased the incidence of gastric adenocarcinomas. Arctigenin, in contrast, failed to attenuate neoplasia at a level of 0.1%. Both NDGA and arctigenin significantly reduced serum 8-hydroxy-2'-deoxyguanosine levels at doses of 0.25 and 0.05% (NDGA), and 0.1% (arctigenin). Administration of 0.25% NDGA significantly suppressed the formation of intestinal metaplasia both in the antrum and the corpus. Although all three lignans dose-dependently inhibited the in vitro proliferation of H. pylori, there were no differences in the titers of anti-H. pylori antibodies or the amount of the H. pylori-specific urease A gene among all H. pylori-infected groups. These results suggest that NDGA might be effective for prevention of gastric carcinogenesis. The possible mechanisms appear to be related to inhibitory effects on progression of gastritis and antioxidative activity rather than direct antimicrobial influence. PMID:17894552

  14. Protection of gerbils from amebic liver abscess by immunization with a recombinant protein derived from the 170-kilodalton surface adhesin of Entamoeba histolytica.

    PubMed Central

    Zhang, T; Stanley, S L

    1994-01-01

    The protozoan parasite Entamoeba histolytica causes extensive morbidity and mortality worldwide through intestinal infection and amebic liver abscess. Here we show that vaccination of gerbils, a standard model for amebic liver abscess, with recombinant proteins derived from the 170-kDa galactose-binding adhesin of E. histolytica and the serine-rich E. histolytica protein or a combination of the two recombinant antigens provides excellent protection against subsequent hepatic challenge with virulent E. histolytica trophozoites. PMID:8188384

  15. Extremely Low Frequency Magnetic Field (50 Hz, 0.5 mT) Reduces Oxidative Stress in the Brain of Gerbils Submitted to Global Cerebral Ischemia

    PubMed Central

    Rauš Balind, Snežana; Selaković, Vesna; Radenović, Lidija; Prolić, Zlatko; Janać, Branka

    2014-01-01

    Magnetic field as ecological factor has influence on all living beings. The aim of this study was to determine if extremely low frequency magnetic field (ELF-MF, 50 Hz, 0.5 mT) affects oxidative stress in the brain of gerbils submitted to 10-min global cerebral ischemia. After occlusion of both carotid arteries, 3-month-old gerbils were continuously exposed to ELF-MF for 7 days. Nitric oxide and superoxide anion production, superoxide dismutase activity and index of lipid peroxidation were examined in the forebrain cortex, striatum and hippocampus on the 7th (immediate effect of ELF-MF) and 14th day after reperfusion (delayed effect of ELF-MF). Ischemia per se increased oxidative stress in the brain on the 7th and 14th day after reperfusion. ELF-MF also increased oxidative stress, but to a greater extent than ischemia, only immediately after cessation of exposure. Ischemic gerbils exposed to ELF-MF had increased oxidative stress parameters on the 7th day after reperfusion, but to a lesser extent than ischemic or ELF-MF-exposed animals. On the 14th day after reperfusion, oxidative stress parameters in the brain of these gerbils were mostly at the control levels. Applied ELF-MF decreases oxidative stress induced by global cerebral ischemia and thereby reduces possible negative consequences which free radical species could have in the brain. The results presented here indicate a beneficial effect of ELF-MF (50 Hz, 0.5 mT) in the model of global cerebral ischemia. PMID:24586442

  16. Helicobacter pylori Induced Gastric Immunopathology Is Associated with Distinct Microbiota Changes in the Large Intestines of Long-Term Infected Mongolian Gerbils

    PubMed Central

    Heimesaat, Markus M.; Fischer, André; Plickert, Rita; Wiedemann, Tobias; Loddenkemper, Christoph; Göbel, Ulf B.

    2014-01-01

    Background Gastrointestinal (GI) inflammation in mice and men are frequently accompanied by distinct changes of the GI microbiota composition at sites of inflammation. Helicobacter (H.) pylori infection results in gastric immunopathology accompanied by colonization of stomachs with bacterial species, which are usually restricted to the lower intestine. Potential microbiota shifts distal to the inflammatory process following long-term H. pylori infection, however, have not been studied so far. Methodology/Principal Findings For the first time, we investigated microbiota changes along the entire GI tract of Mongolian gerbils after 14 months of infection with H. pylori B8 wildtype (WT) or its isogenic ΔcagY mutant (MUT) strain which is defective in the type IV secretion system and thus unable to modulate specific host pathways. Comprehensive cultural analyses revealed that severe gastric diseases such as atrophic pangastritis and precancerous transformations were accompanied by elevated luminal loads of E. coli and enterococci in the caecum and together with Bacteroides/Prevotella spp. in the colon of H. pylori WT, but not MUT infected gerbils as compared to naïve animals. Strikingly, molecular analyses revealed that Akkermansia, an uncultivable species involved in mucus degradation, was exclusively abundant in large intestines of H. pylori WT, but not MUT infected nor naïve gerbils. Conclusion/Significance Taken together, long-term infection of Mongolian gerbils with a H. pylori WT strain displaying an intact type IV secretion system leads to distinct shifts of the microbiota composition in the distal uninflamed, but not proximal inflamed GI tract. Hence, H. pylori induced immunopathogenesis of the stomach, including hypochlorhydria and hypergastrinemia, might trigger large intestinal microbiota changes whereas the exact underlying mechanisms need to be further unraveled. PMID:24941045

  17. The effects of slight pressure oscillations in the far infrasound frequency range on the pars flaccida in gerbil and rabbit ears

    NASA Astrophysics Data System (ADS)

    Didyk, L. A.; Bogdanov, V. B.; Lysenko, V. A.; Didyk, N. P.; Gorgo, Yu P.; Dirckx, J. J. J.

    2007-01-01

    This study was designed to clarify whether the pars flaccida (PF) as a flexible part of the tympanic membrane is capable of reacting to pressure oscillations (PO) with amplitudes and frequencies typical for natural atmospheric pressure fluctuations in the far infrasound frequency range (APF). If so, the PF mechanical reactions to APF might be involved in the overall physiologic regulation processes, which make organisms susceptible to APF. The displacements of the PF in response to PO were measured in vitro in ears of gerbils and rabbits by means of laser Doppler vibrometry. The index of the PF reactivity (Ra) was determined as the ratio of the amplitude of the PF oscillations (PFO) to the amplitude of the PO. All kinds of PO applied caused PFO. The amplitude of the PFO increased when the amplitude of the PO was increased. In gerbils, a decrease in Ra with the increase in amplitude of the PO was observed. In the range of PO lowest amplitudes (4-20 Pa) Ra proved to be 1.4 times higher than in the range of highest amplitudes (90-105 Pa). Considering that the natural APF are usually within the range of ±20 Pa, this fact points to an important contribution of the PF to the pressure dynamics in the middle ear (ME) of gerbils. In rabbit ears, Ra was lower and recovery from plastic deformation was slower than in gerbils. Our findings are in line with the suggestion that the PF might play an important role in respect of adaptation to natural APF.

  18. Fermented soybeans, Chungkookjang, prevent hippocampal cell death and β-cell apoptosis by decreasing pro-inflammatory cytokines in gerbils with transient artery occlusion.

    PubMed

    Park, Sunmin; Kim, Da Sol; Kang, Sunna; Moon, Bo Reum

    2016-02-01

    Since Chungkookjang, a short-term fermented soybean, is known to improve glucose metabolism and antioxidant activity, it may prevent the neurological symptoms and glucose disturbance induced by artery occlusion. We investigated the protective effects and mechanisms of traditional (TFC) and standardized Chungkookjang fermented with Bacillus licheniformis (BLFC) against ischemia/reperfusion damage in the hippocampal CA1 region and against hyperglycemia after transient cerebral ischemia in gerbils. Gerbils were subjected to either an occlusion of the bilateral common carotid arteries for 8 min to render them ischemic or a sham operation. Ischemic gerbils were fed either a 40% fat diet containing 10% of either cooked soybean (CSB), TFC, or BLFC for 28 days. Neuronal cell death and cytokine expression in the hippocampus, neurological deficit, serum cytokine levels, and glucose metabolism were measured. TFC and BLFC contained more isoflavonoid aglycones than CSB. Artery occlusion increased the expressions of IL-1β and TNF-α as well as cell death in the hippocampal CA1 region and induced severe neurological symptoms. CSB, TFC, and BLFC prevented the neuronal cell death and the symptoms such as dropped eyelid, bristling hair, reduced muscle tone and flexor reflex, and abnormal posture and walking patterns, and suppressed cytokine expressions. CSB was less effective than TFC and BLFC. Artery occlusion induced glucose intolerance due to decreased insulin secretion and β-cell mass. TFC and BLFC prevented the impairment of glucose metabolism by artery occlusion. Especially TFC and BLFC increased β-cell proliferation and suppressed the β-cell apoptosis by suppressing TNF-α and IL-1β which in turn decreased cleaved caspase-3 that caused apoptosis. In conclusion, TFC and BLFC may prevent and alleviate neuronal cell death in the hippocampal CA1 region and neurological symptoms and poststroke hyperglycemia in gerbils with artery occlusion. This might be associated with

  19. Innate defensive behaviour and panic-like reactions evoked by rodents during aggressive encounters with Brazilian constrictor snakes in a complex labyrinth: behavioural validation of a new model to study affective and agonistic reactions in a prey versus predator paradigm.

    PubMed

    Guimarães-Costa, Raquel; Guimarães-Costa, Maria Beatriz; Pippa-Gadioli, Leonardo; Weltson, Alfredo; Ubiali, Walter Adriano; Paschoalin-Maurin, Tatiana; Felippotti, Tatiana Tocchini; Elias-Filho, Daoud Hibrahim; Laure, Carlos Júlio; Coimbra, Norberto Cysne

    2007-09-15

    Defensive behaviour has been extensively studied, and non-invasive methodologies may be interesting approaches to analyzing the limbic system function as a whole. Using experimental models of animals in the state of anxiety has been fundamental in the search for new anxiolytic and antipanic compounds. The aim of this present work is to examine a new model for the study of affective behaviour, using a complex labyrinth consisting of an arena and galleries forming a maze. Furthermore, it aims to compare the defensive behaviour of Wistar rats, Mongolian gerbils and golden hamsters in a complex labyrinth, as well as the defensive behaviour of Meriones unguiculatus in aggressive encounters with either Epicrates cenchria assisi or Boa constrictor amarali in this same model. Among species presently studied, the Mongolian gerbils showed better performance in the exploration of both arena and galleries of the labyrinth, also demonstrating less latency in finding exits of the galleries. This increases the possibility of survival, as well as optimizes the events of encounter with the predator. The duration of alertness and freezing increased during confrontation with living Epicrates, as well as the duration of exploratory behaviour in the labyrinth. There was an increase in the number of freezing and alertness behaviours, as well as in duration of alertness during confrontations involving E.c. assisi, compared with behavioural reactions elicited by jirds in presence of B.c. amarali. Interestingly, the aggressive behaviour of Mongolian gerbils was more prominent against B.c. amarali compared with the other Boidae snake. E.c. assisi elicited more offensive attacks and exhibited a greater time period of body movement than B.c. amarali, which spent more time in the arena and in defensive immobility than the E.c. assisi. Considering that jirds evoked more fear-like reaction in contact with E.c. assisi, a fixed E.c. assisi kept in a hermetically closed acrylic box was used as

  20. Vaccination of Gerbils with Bm-103 and Bm-RAL-2 Concurrently or as a Fusion Protein Confers Consistent and Improved Protection against Brugia malayi Infection

    PubMed Central

    Arumugam, Sridhar; Wei, Junfei; Liu, Zhuyun; Abraham, David; Bell, Aaron; Bottazzi, Maria Elena; Hotez, Peter J.; Zhan, Bin; Lustigman, Sara; Klei, Thomas R.

    2016-01-01

    Background The Brugia malayi Bm-103 and Bm-RAL-2 proteins are orthologous to Onchocerca volvulus Ov-103 and Ov-RAL-2, and which were selected as the best candidates for the development of an O. volvulus vaccine. The B. malayi gerbil model was used to confirm the efficacy of these Ov vaccine candidates on adult worms and to determine whether their combination is more efficacious. Methodology and Principle Findings Vaccine efficacy of recombinant Bm-103 and Bm-RAL-2 administered individually, concurrently or as a fusion protein were tested in gerbils using alum as adjuvant. Vaccination with Bm-103 resulted in worm reductions of 39%, 34% and 22% on 42, 120 and 150 days post infection (dpi), respectively, and vaccination with Bm-RAL-2 resulted in worm reductions of 42%, 22% and 46% on 42, 120 and 150 dpi, respectively. Vaccination with a fusion protein comprised of Bm-103 and Bm-RAL-2 resulted in improved efficacy with significant reduction of worm burden of 51% and 49% at 90 dpi, as did the concurrent vaccination with Bm-103 and Bm-RAL-2, with worm reduction of 61% and 56% at 90 dpi. Vaccination with Bm-103 and Bm-RAL-2 as a fusion protein or concurrently not only induced a significant worm reduction of 61% and 42%, respectively, at 150 dpi, but also significantly reduced the fecundity of female worms as determined by embryograms. Elevated levels of antigen-specific IgG were observed in all vaccinated gerbils. Serum from gerbils vaccinated with Bm-103 and Bm-RAL-2 individually, concurrently or as a fusion protein killed third stage larvae in vitro when combined with peritoneal exudate cells. Conclusion Although vaccination with Bm-103 and Bm-RAL-2 individually conferred protection against B. malayi infection in gerbils, a more consistent and enhanced protection was induced by vaccination with Bm-103 and Bm-RAL-2 fusion protein and when they were used concurrently. Further characterization and optimization of these filarial vaccines are warranted. PMID:27045170

  1. Neuroprotective properties of a protein kinase inhibitor against ischaemia-induced neuronal damage in rats and gerbils.

    PubMed Central

    Satoh, S.; Ikegaki, I.; Suzuki, Y.; Asano, T.; Shibuya, M.; Hidaka, H.

    1996-01-01

    1. The neuroprotective properties of fasudil (HA1077), a novel protein kinase inhibitor, were evaluated in two animal models of cerebral ischaemia: transient bilateral carotid artery occlusion in Mongolian gerbils and cerebral microembolization in rats. 2. The cytoprotective effect of fasudil on delayed neuronal death in gerbils was compared with the effects of nimodipine, a calcium channel antagonist and ozagrel, a thromboxane A2 synthetase inhibitor. The average of the neuronal cell density in the ischaemic control group was 17.8 +/- 2.1 cells mm-1, whereas fasudil (30 mg kg-1) significantly diminished the loss of CA1 neurones with the average of the neuronal cell density of 101.0 +/- 22.0 cells mm-1; nimodipine (10 mg kg-1) and ozagrel (30 mg kg-1) did not significantly protect against the ischaemia-induced neuronal loss. 3. In the rat model, the effects of fasudil on the histological and neurological consequences of cerebral microembolization produced via the injection of microspheres were examined. Twenty-four hours after the injection of microspheres into the internal carotid artery, all animals in the control group showed typical symptoms of stroke. Neurological function was significantly improved in the fasudil-treated animals. In the controls, the infarcted area in a cortical slice selected to include the hippocampal area was 0.25 +/- 0.01 cm2 (mean +/- s.e.mean) (43.9 +/- 2.4% of cortical section of the half hemisphere); the difference was significant compared to the mean area of 32.7 +/- 2.8 and 21.5 +/- 4.8% observed in rats treated with fasudil (3, 10 mg kg-1), respectively. Fasudil (10 mg kg-1) significantly suppressed the increased water content in ischaemic brain tissues (saline-treated rats, 82.4 +/- 0.2% vs fasudil-treated rats, 81.0 +/- 0.4%). 4. These results suggest that: (i) various protein kinases are involved in the pathogenesis of ischaemic injury; and (ii) the inhibition of protein kinases may be efficacious in preventing neuronal death

  2. Inhibitory effect of etodolac, a selective cyclooxygenase-2 inhibitor, on stomach carcinogenesis in Helicobacter pylori-infected Mongolian gerbils

    SciTech Connect

    Magari, Hirohito; Shimizu, Yasuhito; Inada, Ken-ichi; Enomoto, Shotaro; Tomeki, Tatsuji; Yanaoka, Kimihiko; Tamai, Hideyuki; Arii, Kenji; Nakata, Hiroya; Oka, Masashi; Utsunomiya, Hirotoshi; Tsutsumi, Yutaka; Tsukamoto, Tetsuya; Tatematsu, Masae; Ichinose, Masao E-mail: ichinose@wakayama-med.ac.jp

    2005-08-26

    The effect of the selective COX-2 inhibitor, etodolac, on Helicobacter pylori (Hp)-associated stomach carcinogenesis was investigated in Mongolian gerbils (MGs). Hp-infected MGs were fed for 23 weeks with drinking water containing 10 ppm N-methyl-N-nitrosourea. They were then switched to distilled water and placed on a diet containing 5-30 mg/kg/day etodolac for 30 weeks. We found that etodolac dose-dependently inhibited the development of gastric cancer, and no cancer was detected at a dose of 30 mg/kg/day. Etodolac did not affect the extent of inflammatory cell infiltration or oxidative DNA damage, but it significantly inhibited mucosal cell proliferation and dose-dependently repressed the development of intestinal metaplasia in the stomachs of Hp-infected MGs. These results suggest that COX-2 is a key molecule in inflammation-mediated stomach carcinogenesis and that chemoprevention of stomach cancer should be possible by controlling COX-2 expression or activity.

  3. Behavioral effects and neural changes induced by continuous and not continuous treadmill training, post bilateral cerebral ischemia in gerbils.

    PubMed

    Kitabatake, Takae Tamy; Marini, Luana de Castro; Gonçalves, Renata Batagini; Bertolino, Guilherme; de Souza, Hugo Celso Dutra; de Araujo, João Eduardo

    2015-09-15

    This study aims to investigate the effects of treadmill training and the possible influences of the start, regularity, and duration after experimental ischemic stroke. We performed bilateral occlusion of both the carotid arteries for 5 min in Mongolian gerbils. The training groups were: continuous training for 5 consecutive days or not continuous training for 3 non-consecutive days. The groups remained in the treadmill for 15 min, and the training started 12 or 24h after the stroke. In the activity cage (AC), behaviors of crossing and distance traveled were registered. The forced motor behavior was analyzed by a Rota Rod test. After the experiments, the brains were perfused, and coronal sections of the striatum, motor cortex M1, and CA1 area of the hippocampus were cut and stained with hematoxylin and eosin. Behavioral and morphological data analysis was performed by an ANOVA and MANCOVA. Results showed an increased density of neurons in the CA1 area of the hippocampus, motor cortex M1, and the striatum in ischemic training groups compared to the not training ischemic groups. Animals subjected to continuous training that started 24h after ischemia showed a satisfactory behavior in the AC and a higher number of striatal neurons when compared to ischemic animals. The animals in the not continuous training started 12h after the stroke showed an unsatisfactory performance in the AC and Rota Rod. These findings suggest that early training and not continuous training are inadequate for motor behavior improvement after stroke. PMID:25975174

  4. Reduction in the body content of DDE in the Mongolian gerbil treated with sucrose polyester and caloric restriction

    SciTech Connect

    Mutter, L.C.; Blanke, R.V.; Jandacek, R.J.; Guzelian, P.S.

    1988-03-15

    It has previously been shown that oral administration to rats of sucrose polyester (SPE4), a nonabsorbable lipophilic binding agent, greatly stimulates the fecal excretion of coorally administered DDT5. To determine whether this agent would stimulate the excretion of persistent metabolites of DDT stored in body tissues, we treated a group of gerbils with (/sup 14/C)-DDT and monitored the fecal excretion of radioactivity for several months until a terminal, log-linear phase of excretion was observed. At this point, when greater than 75% of the fecal radioactivity was identified as (/sup 14/C)DDE, we fed the animals diets containing up to 10% sucrose polyester and found that the rate of excretion of radioactivity in the stool promptly increased two to three times as compared to the rate in the preceding control period. Some rats were subjected to a 25-50% restriction in total food allotment, but this produced no significant change in fecal excretion of total radioactivity. However, when food restriction was combined with administration of sucrose polyester, there was a dramatic, eightfold average increase in excretion of fecal radioactivity. This synergistic effect was reversed (within 24 hr) when the animals were transferred to a normal diet. Measurement of total body radioactivity confirmed that food restriction plus sucrose polyester treatment reduced the body content of the pesticide. We conclude that stimulation of intestinal excretion may offer a new approach to treatment of patients exposed to lipophilic environmental contaminants.

  5. Mitochondrial DNA diversity in the populations of great gerbils, Rhombomys opimus, the main reservoir of cutaneous leishmaniasis.

    PubMed

    Oshaghi, Mohammad Ali; Rassi, Yavar; Tajedin, Leila; Abai, Mohammad Reza; Akhavan, Amir Ahmad; Enayati, Ahmadali; Mohtarami, Fatemeh

    2011-08-01

    Accurate identification of animal reservoirs of transmissible diseases is an absolute requirement to any epidemiological survey of zoonoses and is essential for predicting species-specific population outbreaks and therefore to develop accurate ecological control strategies. The systematic status of the great gerbil (Rhombomys opimus) remains unclear, despite the fundamental role of these rodents as the main known reservoir hosts of the protozoan parasite Leishmania major in the epidemiology of zoonotic cutaneous leishmaniasis (ZCL) in central and south Asia. In the present work, we represent molecular evidence supporting the identification of at least two major lineages (subspecies) within the species of R. opimus in Iran. Analysis of the mitochondrial cytochrome b (cyt b) gene, revealed a range of 1-10% genetic variation among populations, which were well associated with biogeographic origins and subspecies. Results of laboratory cross hybridization between the subspecies and finding sympatric haplotypes of the two subspecies suggested that no pre- or post-zygotic barriers exist between the subspecies indicating that they still belong to a single taxon. However, the amount of genetic variations between populations/subspecies is high enough to lead them to speciation in future. Implications of such findings on the eco-epidemiology of ZCL in Iran are discussed. PMID:21683054

  6. Prenatal exposure to testosterone masculinises the female gerbil and promotes the development of lesions in the prostate (Skene's gland).

    PubMed

    Biancardi, Manoel F; Perez, Ana P S; Caires, Cássia Regina Suzuki; Góes, Rejane M; Vilamaior, Patrícia S L; Santos, Fernanda C A; Taboga, Sebastião R

    2015-09-01

    Androgenic imbalance may disrupt prostate development, leading to morphological alterations in adulthood and predisposing this gland to develop diseases during ageing. However, little is known about the endocrine disruption of the prostate that is caused by androgenic compounds, especially in female experimental models. Therefore, this study aimed to evaluate the prostates of aged female gerbils exposed to testosterone at certain periods in intrauterine and postnatal life, to determine whether exposure at a particular age increases susceptibility to prostatic lesions in these animals. To this end, morphological, stereological, immunohistochemical and immunofluorescence analyses were employed. It was found that females exposed to testosterone during intrauterine life were masculinised, showing increased anogenital distance, absence of the vaginal opening and ectopic development of prostatic tissue. Several areas of adenomatous hyperplasia, generally associated with inflammatory foci and mainly located in the ectopic prostatic tissue around the vaginal wall, were also observed. In conclusion, the results showed that abnormal prenatal exposure to testosterone severely affects the reproductive systems of female animals by disrupting normal prostate morphogenesis and increasing susceptibility to the development of prostatic diseases during ageing. PMID:25483231

  7. Luminal non-selective cation and outwardly rectifying chloride channels in cultured strial marginal cells from gerbil.

    PubMed

    Yeh, T; Van den Abbeele, T; Marianovski, R; Herman, P; Tran Ba Huy, P

    1995-10-01

    Ionic channels located on the luminal side of strial marginal cells (MCs) of gerbil in culture were investigated using the patch-clamp technique. Two types of channels were identified. The most frequently recorded single-channel activity corresponded to a non-selective cation (NSC) channel with a conductance of 23.7 +/- 0.2 pS (n = 18) in symmetrical NaCl conditions. The channel was activated by internal Ca2+ and inhibited by internal adenine nucleotides and flufenamic acid. Spontaneous activity of NSC channels was found in 16% of the cell-attached patches and with a very high density (9 +/- 2 levels/patch, n = 28) in 100% of the excised patches. An outwardly rectifying chloride (ORC) channel was also identified in 14% of the patches but only after excision. The channel exhibited at 0 mV a unit conductance of 26.8 +/- 1.3 pS (n = 8) and a strong outward rectification in symmetrical NaCl conditions, and the open probability increased with depolarization. The luminal NSC channel and the ORC channel evidenced in this study might participate in the production of endolymph. Although extrapolation of the presents results to the in vivo situation should be made with caution, this study suggests that culture of strial MCs may be a suitable model for investigation of endolymph physiology. PMID:8975008

  8. Protein–energy malnutrition increases activation of the transcription factor, nuclear factor κB, in the gerbil hippocampus following global ischemia☆

    PubMed Central

    Ji, Liang; Nazarali, Adil J.; Paterson, Phyllis G.

    2013-01-01

    Protein–energy malnutrition (PEM) exacerbates functional impairment caused by brain ischemia. This is correlated with reactive gliosis, which suggests an increased inflammatory response. The objective of the current study was to investigate if PEM increases hippocampal activation of nuclear factor κB (NFκB), a transcription factor that amplifies the inflammatory response involved in ischemic brain injury. Mongolian gerbils (11–12 weeks old) were randomly assigned to control diet (12.5% protein) or protein-deficient diet (2%) for 4 weeks. The 2% protein group had a 15% decrease in voluntary food intake (P<.001; unpaired t test), resulting in PEM. Body weight after 4 weeks was 20% lower in the PEM group (P<.001). Gerbils were then exposed to sham surgery or global ischemia induced by 5-min bilateral common carotid artery occlusion. PEM independently increased hippocampal NFκB activation detected by electrophoretic mobility shift assay at 6 h after surgery (P=.014; 2-factor ANOVA). Ischemia did not significantly affect NFκB activation nor was there interaction between diet and ischemia. Serum glucose and cortisol concentrations at 6 h postischemia were unaltered by diet or ischemia. A second experiment using gerbils of the same age and feeding paradigm demonstrated that PEM also increases hippocampal NFκB activation in the absence of surgery. These findings suggest that PEM, which exists in 16% of elderly patients at admission for stroke, may worsen outcome by increasing activation of NFκB. Since PEM increased NFκB activation independent of ischemia or surgery, the data also have implications for the inflammatory response of the many individuals affected globally by PEM. PMID:18430555

  9. Ischemic preconditioning maintains the immunoreactivities of glucokinase and glucokinase regulatory protein in neurons of the gerbil hippocampal CA1 region following transient cerebral ischemia.

    PubMed

    Cho, Young Shin; Cho, Jun Hwi; Shin, Bich-Na; Cho, Geum-Sil; Kim, In Hye; Park, Joon Ha; Ahn, Ji Hyeon; Ohk, Taek Geun; Cho, Byung-Ryul; Kim, Young-Myeong; Hong, Seongkweon; Won, Moo-Ho; Lee, Jae-Chul

    2015-10-01

    Glucokinase (GK) is involved in the control of blood glucose homeostasis. In the present study, the effect of ischemic preconditioning (IPC) on the immunoreactivities of GK and its regulatory protein (GKRP) following 5 min of transient cerebral ischemia was investigated in gerbils. The gerbils were randomly assigned to four groups (sham‑operated group, ischemia‑operated group, IPC + sham‑operated group and IPC + ischemia‑operated group). IPC was induced by subjecting the gerbils to 2 min of ischemia, followed by 1 day of recovery. In the ischemia‑operated group, a significant loss of neurons was observed in the stratum pyramidale (SP) of the hippocampal CA1 region (CA1) at 5 days post‑ischemia; however, in the IPC+ischemia‑operated group, the neurons in the SP were well protected. Following immunohistochemical investigation, the immunoreactivities of GK and GKRP in the neurons of the SP were markedly decreased in the CA1, but not the CA2/3, from 2 days post‑ischemia, and were almost undetectable in the SP 5 days post‑ischemia. In the IPC + ischemia‑operated group, the immunoreactivities of GK and GKRP in the SP of the CA1 were similar to those in the sham‑group. In brief, the findings of the present study demonstrated that IPC notably maintained the immunoreactivities of GK and GKRP in the neurons of the SP of CA1 following ischemia‑reperfusion. This indicated that GK and GKRP may be necessary for neuron survival against transient cerebral ischemia. PMID:26134272

  10. Ischemic preconditioning maintains the immunoreactivities of glucokinase and glucokinase regulatory protein in neurons of the gerbil hippocampal CA1 region following transient cerebral ischemia

    PubMed Central

    CHO, YOUNG SHIN; CHO, JUN HWI; SHIN, BICH-NA; CHO, GEUM-SIL; KIM, IN HYE; PARK, JOON HA; AHN, JI HYEON; OHK, TAEK GEUN; CHO, BYUNG-RYUL; KIM, YOUNG-MYEONG; HONG, SEONGKWEON; WON, MOO-HO; LEE, JAE-CHUL

    2015-01-01

    Glucokinase (GK) is involved in the control of blood glucose homeostasis. In the present study, the effect of ischemic preconditioning (IPC) on the immunoreactivities of GK and its regulatory protein (GKRP) following 5 min of transient cerebral ischemia was investigated in gerbils. The gerbils were randomly assigned to four groups (sham-operated group, ischemia-operated group, IPC + sham-operated group and IPC + ischemia-operated group). IPC was induced by subjecting the gerbils to 2 min of ischemia, followed by 1 day of recovery. In the ischemia-operated group, a significant loss of neurons was observed in the stratum pyramidale (SP) of the hippocampal CA1 region (CA1) at 5 days post-ischemia; however, in the IPC+ischemia-operated group, the neurons in the SP were well protected. Following immunohistochemical investigation, the immunoreactivities of GK and GKRP in the neurons of the SP were markedly decreased in the CA1, but not the CA2/3, from 2 days post-ischemia, and were almost undetectable in the SP 5 days post-ischemia. In the IPC + ischemia-operated group, the immunoreactivities of GK and GKRP in the SP of the CA1 were similar to those in the sham-group. In brief, the findings of the present study demonstrated that IPC notably maintained the immunoreactivities of GK and GKRP in the neurons of the SP of CA1 following ischemia-reperfusion. This indicated that GK and GKRP may be necessary for neuron survival against transient cerebral ischemia. PMID:26134272

  11. Effect of ischemic preconditioning on antioxidant status in the gerbil hippocampal CA1 region after transient forebrain ischemia

    PubMed Central

    Park, Seung Min; Park, Chan Woo; Lee, Tae-Kyeong; Cho, Jeong Hwi; Park, Joon Ha; Lee, Jae-Chul; Chen, Bai Hui; Shin, Bich-Na; Ahn, Ji Hyeon; Tae, Hyun-Jin; Shin, Myoung Cheol; Ohk, Taek Geun; Cho, Jun Hwi; Won, Moo-Ho; Choi, Soo Young; Kim, In Hye

    2016-01-01

    Ischemic preconditioning (IPC) is a condition of sublethal transient global ischemia and exhibits neuroprotective effects against subsequent lethal ischemic insult. We, in this study, examined the neuroprotective effects of IPC and its effects on immunoreactive changes of antioxidant enzymes including superoxide dismutase (SOD) 1 and SOD2, catalase (CAT) and glutathione peroxidase (GPX) in the gerbil hippocampal CA1 region after transient forebrain ischemia. Pyramidal neurons of the stratum pyramidale (SP) in the hippocampal CA1 region of animals died 5 days after lethal transient ischemia without IPC (8.6% (ratio of remanent neurons) of the sham-operated group); however, IPC prevented the pyramidal neurons from subsequent lethal ischemic injury (92.3% (ratio of remanent neurons) of the sham-operated group). SOD1, SOD2, CAT and GPX immunoreactivities in the sham-operated animals were easily detected in pyramidal neurons in the stratum pyramidale (SP) of the hippocampal CA1 region, while all of these immunoreactivities were rarely detected in the stratum pyramidale at 5 days after lethal transient ischemia without IPC. Meanwhile, their immunoreactivities in the sham-operated animals with IPC were similar to (SOD1, SOD2 and CAT) or higher (GPX) than those in the sham-operated animals without IPC. Furthermore, their immunoreactivities in the stratum pyramidale of the ischemia-operated animals with IPC were steadily maintained after lethal ischemia/reperfusion. Results of western blot analysis for SOD1, SOD2, CAT and GPX were similar to immunohistochemical data. In conclusion, IPC maintained or increased the expression of antioxidant enzymes in the stratum pyramidale of the hippocampal CA1 region after subsequent lethal transient forebrain ischemia and IPC exhibited neuroprotective effects in the hippocampal CA1 region against transient forebrain ischemia.

  12. Reduction in the body content of DDE in the Mongolian gerbil treated with sucrose polyester and caloric restriction.

    PubMed

    Mutter, L C; Blanke, R V; Jandacek, R J; Guzelian, P S

    1988-03-15

    It has previously been shown that oral administration to rats of sucrose polyester (SPE4), a nonabsorbable lipophilic binding agent, greatly stimulates the fecal excretion of coorally administered DDT5 (R.J. Jandacek, 1982, Drug Metab. Rev., 13, 695-714). To determine whether this agent would stimulate the excretion of persistent metabolites of DDT stored in body tissues, we treated a group of gerbils with [14C]-DDT and monitored the fecal excretion of radioactivity for several months until a terminal, log-linear phase of excretion was observed. At this point, when greater than 75% of the fecal radioactivity was identified as [14C]DDE, we fed the animals diets containing up to 10% sucrose polyester and found that the rate of excretion of radioactivity in the stool promptly increased two to three times as compared to the rate in the preceding control period. Some rats were subjected to a 25-50% restriction in total food allotment, but this produced no significant change in fecal excretion of total radioactivity. However, when food restriction was combined with administration of sucrose polyester, there was a dramatic, eightfold average increase in excretion of fecal radioactivity. This synergistic effect was reversed (within 24 hr) when the animals were transferred to a normal diet. Measurement of total body radioactivity confirmed that food restriction plus sucrose polyester treatment reduced the body content of the pesticide. We conclude that stimulation of intestinal excretion may offer a new approach to treatment of patients exposed to lipophilic environmental contaminants. PMID:2451319

  13. Failure in neuroprotection of remote limb ischemic postconditioning in the hippocampus of a gerbil model of transient cerebral ischemia.

    PubMed

    Lee, Jae-Chul; Tae, Hyun-Jin; Chen, Bai Hui; Cho, Jeong Hwi; Kim, In Hye; Ahn, Ji Hyeon; Park, Joon Ha; Shin, Bich-Na; Lee, Hui Young; Cho, Young Shin; Cho, Jun Hwi; Hong, Seongkweon; Choi, Soo Young; Won, Moo-Ho; Park, Chan Woo

    2015-11-15

    Remote ischemic postconditioning (RIPoC) has been proven to provide potent protection of the heart and brain against ischemia-reperfusion injury. However, despite the evidence of cerebral protection with RIPoC is compelling, RIPoC-mediated neuroprotection against transient cerebral ischemic insult is still mired in controversy. In this study, we examined the effect of RIPoC induced by sublathal transient hind limb ischemia on neuronal death in the hippocampus following 5 min of transient cerebral ischemia in gerbils. Animals were randomly assigned to sham-, ischemia-, sham plus (+) RIPoC- and ischemia+RIPoC-groups. RIPoC was induced by three cycles of 5-min and 10-min occlusion-reperfusion of both femoral arteries at predetermined points in time (0, 1, 3, 6, 12 and 24h after transient cerebral ischemia). CV staining, F-J B histofluorescence staining and NeuN immunohistochemistry were carried out to examine neuroprotection in the RIPoC-mediated hippocampus 5 days after ischemia-reperfusion. In the ischemia-group, we found a significant loss of pyramidal cells in the stratum pyramidale (SP) of the hippocampal CA1 region at 5 days post-ischemia compared with the sham-group. In all of the ischemia+RIPoC-groups, the loss of pyramidal cells in the CA1 region at 5 days post-ischemia was not different from that in the ischemia-group. Our present findings indicate that RIPoC does not prevent hippocampal CA1 pyramidal cells from neuronal death induced by transient cerebral ischemia. PMID:26454372

  14. Evaluation of Water-Chemistry and Water-Level Data at the Henderson Road Superfund Site, Upper Merion Township, Montgomery County, Pennsylvania, 1991-2008

    USGS Publications Warehouse

    Sloto, Ronald A.

    2009-01-01

    , which is about 190 feet north of the source area. A much larger area was affected by chlorobenzene than benzene. Chlorobenzene concentrations decreased in the source area and increased at and beyond the site boundary. Water from four wells in and northeast of the source area sampled in 2008 exceeded the 5.06 ug/L ARAR for 1,1-dichloroethane (1,1-DCA). Increases in 1,1-DCA concentration between pre-shutdown samples collected in July 2006 and samples collected in February 2008 ranged from 0.4 to 20 ug/L. Water from two wells in the source area sampled in 2008 exceeded the 175 ug/L ARAR for total xylene. The 1,1-DCA and xylene plumes appear to extend in an east-northeast direction from the source area. Large drawdowns in the Upper Merion Reservoir during droughts in 1998 and 2001 affected water levels in the Chester Valley and at the Henderson Road Site, except for well HR-17-170. After the drought of 2001, water levels in the Chester Valley showed a protracted recovery lasting from September 2001 until June 2005 (46 months). Water-level data were evaluated temporally for 1997-2008 and spatially for (1) June 16, 2003, when the extraction wells were pumping at the full rate prior to the start of the June 2003 shutdown test; (2) July 10, 2006, during the period of reduced pumping after the June 2003 shutdown test; and (3) February 25-29, 2008, when the extraction wells were not pumping. Except for well HR-5-195, wells were categorized as shallow, intermediate-depth, and deep wells. The potentiometric surface for shallow wells did not appear to be affected by pumping of the extraction wells. The general direction of ground-water flow was to the north. The potentiometric surface for intermediate-depth wells showed a cone of depression when the extraction wells were pumping at the full rate but did not show a cone of depression when the extraction wells were pumping at the reduced rate. The ground-water-flow direction was toward the north and northeast, similar to

  15. Gonadotrophin- and androgen precursor-stimulated testosterone secretion by interstitial cells from Mongolian gerbil testes: influence of plasma proteins and elevated temperature.

    PubMed

    Fenske, M

    1988-03-01

    Interstitial cells isolated from Mongolian gerbil testes have been used to investigate the effects of plasma proteins and incubation temperature on HCG- and androgen precursor-stimulated testosterone secretion. Short term (15 min) incubation of interstitial cells with various precursors resulted in a significant increase of testosterone release. On the other hand, no stimulatory effect of HCG (10 mIU) could be observed. Precursor (e.g. progesterone)-stimulated testosterone secretion linearly increased with cell concentrations (0.5 x 10(5) to 4.0 x 10(5) cells/0.7 ml medium, r = less than 0.99, p less than 0.001). In the presence of 50% horse plasma, progesterone-stimulated testosterone secretion was even more pronounced. Similarly, also gerbil, rat, calf or human plasma significantly increased progesterone-stimulated testosterone output. Interestingly, this effect was markedly reduced in the presence of cortisol. While incubation of interstitial cells for 15 min at either 40 degrees C or 42 degrees C had no significant effect on androgen precursor- or HCG-stimulated testosterone secretion, incubation of cells at 44 degrees C resulted in a drastic reduction of HCG-stimulated testosterone release, without affecting progesterone- or DHEA-stimulated testosterone secretion. Taken the simplicity to make interstitial cells unresponsive to HCG into account, heat-treated cells might prove to be a versatile tool to distinguish between HCG- and protein-/androgen precursor-stimulated testosterone secretion in vitro. PMID:2967191

  16. Dose Effect Evaluation and Therapeutic Window of the Neuro-EPO Nasal Application for the Treatment of the Focal Ischemia Model in the Mongolian Gerbil

    PubMed Central

    Teste, Iliana Sosa; Tamos, Yuneidys Mengana; Cruz, Yamila Rodríguez; Cernada, Adriana Muñoz; Rodríguez, Janette Cruz; Martínez, Nelvis Subirós; Antich, Rosa Maria Coro; González-Quevedo, Alina; Rodríguez, Julio Cesar García

    2012-01-01

    Cerebrovascular disease is the third leading cause of death and the leading cause of disability in Cuba and in several developed countries. A possible neuroprotective agent is the rHu-EPO, whose effects have been demonstrated in models of brain ischemia. The Neuro-EPO is a derivative of the rHu-EPO that avoids the stimulation of erythropoiesis. The aim of this study was to determine the Neuro-EPO delivery into the central nervous system (CNS) to exert a neuroprotective effect in cerebral ischemia model of the Mongolian gerbil. The Neuro-EPO in a rate of 249.4 UI every 8 hours for 4 days showed 25% higher viability efficacy (P > 0.01), improving neurological score and behavior of the spontaneous exploratory activity, the preservation of CA3 areas of the hippocampus, the cortex, and thalamic nuclei in the focal ischemia model of the Mongolian gerbil. In summary, this study, the average dose-used Neuro-EPO (249.4 UI/10 μL/every 8 hours for 4 days), proved to be valid indicators of viability, neurological status, and spontaneous exploratory activity, being significantly lower than that reported for the systemically use of the rHu-EPO as a neuroprotectant. Indeed, up to 12 h after brain ischemia is very positive Neuro-EPO administration by the nasal route as a candidate for neuroprotection. PMID:22701364

  17. Hyperthermic preconditioning severely accelerates neuronal damage in the gerbil ischemic hippocampal dentate gyrus via decreasing SODs expressions.

    PubMed

    Kim, Dong Won; Cho, Jeong-Hwi; Cho, Geum-Sil; Kim, In Hye; Park, Joon Ha; Ahn, Ji Hyeon; Chen, Bai Hui; Shin, Bich-Na; Tae, Hyun-Jin; Hong, Seongkweon; Cho, Jun Hwi; Kim, Young-Myeong; Won, Moo-Ho; Lee, Jae-Chul

    2015-11-15

    It is well known that neurons in the dentate gyrus (DG) of the hippocampus are resistant to short period of ischemia. Hyperthermia is a proven risk factor for cerebral ischemia and can produce more extensive brain damage related with mortality rates. The aim of this study was to examine the effect of hyperthermic conditioning (H) on neuronal death, gliosis and expressions of SODs as anti-oxidative enzymes in the gerbil DG following 5 min-transient cerebral ischemia. The animals were randomly assigned to 4 groups: 1) (N+sham)-group was given sham-operation with normothermia (N); 2) (N+ischemia)-group was given 5 min-transient ischemia with N; 3) (H+sham)-group was given sham-operation with H; and 4) (H+ischemia)-group was given 5 min-transient cerebral ischemia with H. H (39±0.5°C) was induced by subjecting the animals to a heating pad for 30 min before and during the operation. In the (N+ischemia)-groups, a significant neuronal death was observed in the polymorphic layer (PL) from 1 day after ischemia-reperfusion. In the (H+ischemia)-groups, neuronal death was also observed in the PL from 1day post-ischemia; the degree of the neuronal death was severer than that in the (N+ischemia)-groups. In addition, we examined the gliosis of astrocytes and microglia using anti-glial fibrillary acidic protein (GFAP) and anti- ionized calcium-binding adapter molecule 1 (Iba-1). GFAP(+) and Iba-1(+) glial cells were much more activated in the (H+ischemia)-groups than those in the (N+ischemia)-groups. On the other hand, immunoreactivities and levels of SOD1 rather than SOD2 were significantly lower in the (H+ischemia)-groups than those in the (N+ischemia)-groups. In brief, on the basis of our findings, we suggest that cerebral ischemic insult with hyperthermic conditioning brings up severer neuronal damage and gliosis in the polymorphic layer through reducing SOD1 expression rather than SOD2 expression in the DG. PMID:26365286

  18. Differences in the protein expression levels of Trx2 and Prx3 in the hippocampal CA1 region between adult and aged gerbils following transient global cerebral ischemia.

    PubMed

    Lee, Choong Hyun; Park, Joon Ha; Cho, Jeong-Hwi; Ahn, Ji Hyeon; Bae, Eun Joo; Won, Moo-Ho

    2015-08-01

    The thioredoxin (Trx) and peroxiredoxin (Prx) redox system is associated with neuronal damage and neuroprotective effects via the regulation of oxidative stress in brain ischemia. In the present study, ischemia-induced changes in the protein expression levels of Trx2 and Prx3 in the stratum pyramidale (SP) of the hippocampal CA1 region were investigated in adult and aged gerbils, subjected to 5 min of transient global cerebral ischemia, using immunohistochemistry and western blot analysis. In the adult ischemia-group, minimal Trx2 immunoreactivity was detected in the SP 2 days after ischemia-reperfusion. In the aged animals, the Trx2 immunoreactivity in the sham-group was marginally lower compared with that in the adult sham-group. In the aged ischemia-group, Trx2 immunoreactivity in the SP was significantly higher 1, 2 and 4 days post-ischemia, compared with that in the adult ischemia-group and, in the 5 days post-ischemia group, Trx2 immunoreactivity was significantly decreased in the SP. Prx3 immunoreactivity in the SP of the adult ischemia-group was significantly decreased from 4 days after ischemia-reperfusion. In the aged animals, Prx3 immunoreactivity in the sham-group was also marginally lower compared with that in the adult sham-group. Prx3 immunoreactivity in the aged ischemia-group was also significantly higher 1, 2 and 4 days post-ischemia, compared with the adult ischemia-group; however, the Prx3 immunoreactivity was significantly decreased 5 days post-ischemia. The western blot analyses revealed that the pattern of changes in the protein levels of Trx2 and Prx3 in the adult and aged hippocampal CA1 region following ischemic damage were similar to the results obtained in the immunohistochemical data. These findings indicated that cerebral ischemia lead to different protein expression levels of Trx2 and Prx3 in the hippocampal CA1 region between adult and aged gerbils, and these differences may be associated with more delayed neuronal death in the aged

  19. Splenic melanosis in agouti and black mice.

    PubMed

    Michalczyk-Wetula, Dominika; Wieczorek, Justyna; Płonka, Przemysław M

    2015-01-01

    An interesting example of extradermal deposition of melanin in vertebrates, notably in mammals, is splenic melanosis. In particular, if the phenomenon of splenic melanosis is correlated with hair or skin pigmentation, it must reflect the amount and perhaps the quality of pigment produced in hair follicle melanocytes. The present paper is our first study on splenic pigmentation in mice of phenotype agouti. We used untreated mixed background mice C57BL/6;129/SvJ (black - a/a, agouti - A/a, A/A), and as a control - black C57BL/6 and agouti fur from 129/SvJ mice, Mongolian gerbils (Meriones unguiculatus) and golden hamsters (Mesocricetus auratus). After euthanasia skin and spleen was evaluated macroscopically, photographed and collected for further analysis using Fontana-Masson and hematoxylin-eosin staining and electron paramagnetic resonance (EPR) at X-band. Spleens of the agouti mice revealed splenic melanosis but were slightly weaker pigmented than their black counterparts, while the presence of pheomelanin was difficult to determine. The fur of both phenotypes was of similar melanin content, with the same tendency as in the spleens. The contribution of pheomelanin in the agouti fur was on the border of detectability by EPR. Histological and EPR analysis confirmed the presence of melanin in the melanotic spleens. The shape of the EPR signal showed a dominance of eumelanin in fur and in melanized spleens in both phenotypes of mice. Therefore, splenic melanosis does reflect the hair follicle pigmentation not only in black, but also in agouti mice. PMID:26291042

  20. Tissue reconstruction in 3D-spheroids from rodent retina in a motion-free, bioreactor-based microstructure.

    PubMed

    Rieke, Matthias; Gottwald, Eric; Weibezahn, Karl-Friedrich; Layer, Paul Gottlob

    2008-12-01

    While conventional rotation culture-based retinal spheroids are most useful to study basic processes of retinogenesis and tissue regeneration, they are less appropriate for an easy and inexpensive mass production of histotypic 3-dimensional tissue spheroids, which will be of utmost importance for future bioengineering, e.g. for replacement of animal experimentation. Here we compared conventionally reaggregated spheroids derived from dissociated retinal cells from neonatal gerbils (Meriones unguiculatus) with spheroids cultured on a novel microscaffold cell chip (called cf-chip) in a motion-free bioreactor. Reaggregation and developmental processes leading to tissue formation, e.g. proliferation, apoptosis and differentiation were observed during the first 10 days in vitro (div). Remarkably, in each cf-chip micro-chamber, only one spheroid developed. In both culture systems, sphere sizes and proliferation rates were almost identical. However, apoptosis was only comparably high up to 5 div, but then became negligible in the cf-chip, while it up-rose again in the conventional culture. In both systems, immunohistochemical characterisation revealed the presence of Müller glia cells, of ganglion, amacrine, bipolar and horizontal cells at a highly comparable arrangement. In both systems, photoreceptors were detected only in spheroids from P3 retinae. Benefits of the chip-based 3D cell culture were a reliable sphere production at enhanced viability, the feasibility of single sphere observation during cultivation time, a high reproducibility and easy control of culture conditions. Further development of this approach should allow high-throughput systems not only for retinal but also other types of histotypic spheroids, to become suitable for environmental monitoring and biomedical diagnostics. PMID:19023488

  1. Re-description of Cryptosporidium cuniculus Inman and Takeuchi, 1979 (Apicomplexa: Cryptosporidiidae): morphology, biology and phylogeny.

    PubMed

    Robinson, Guy; Wright, Steve; Elwin, Kristin; Hadfield, Stephen J; Katzer, Frank; Bartley, Paul M; Hunter, Paul R; Nath, Mintu; Innes, Elisabeth A; Chalmers, Rachel M

    2010-11-01

    To provide re-description of Cryptosporidium cuniculus Inman and Takeuchi, 1979 (synonymous with rabbit genotype), a species closely related to Cryptosporidium hominis, the morphology, natural and experimental host specificity, and genetic characterisation were investigated. The morphology and diagnostic characteristics are typical of other intestinal species of Cryptosporidium, albeit with slightly larger oocysts (5.55-6.40×5.02-5.92 μm; mean 5.98×5.38 μm; length:width=1.1; n=50). Natural hosts appear to be European rabbits (Oryctolagus cuniculus) and humans (Homo sapiens). Experimental infections have been established in weanling rabbits (O. cuniculus), immunosuppressed Mongolian gerbils (Meriones unguiculatus) and immunosuppressed adult Porton strain mice (Mus musculus), but not in neonatal mice. Patterns of infection measured by oocyst shedding are significantly different compared with C. hominis, particularly in rabbits. Histological examination reveals endogenous stages in the brush border of the epithelium of the small intestinal villi, but clinical signs are absent. Inoculation of human HCT-8 cells results in discrete clusters of endogenous stages. A close relationship with C. hominis is inferred from molecular analyses at the ssrRNA, 70 kDa heat shock protein (HSP70), actin, Cryptosporidium oocyst wall protein (COWP), 60 kDa glycoprotein (GP60) genes and a region encoding a product of unknown function (LIB13). Sequences contained limited, consistent polymorphisms at the ssrRNA, HSP70 and actin genes, were identical at the COWP and LIB13 genes and demonstrated two unique families at the GP60 gene. Although genetically closely related, there are significant biological differences between C. cuniculus and C. hominis that support these protozoa being separate species. This is based on the current understanding of these organisms and relies on the assumption that mating between these species would not normally occur. If this is subsequently demonstrated

  2. A rodent model for artificial gravity: VOR adaptation and Fos expression.

    PubMed

    Kaufman, Galen; Weng, Tianxiang; Ruttley, Tara

    2005-01-01

    Vestibulo-ocular reflex (VOR) adaptation and brainstem Fos expression as a result of short radius cross-coupling stimuli were investigated to find neural correlates of the inherent Coriolis force asymmetry from an artificial gravity (AG) environment. Head-fixed gerbils (Meriones unguiculatus, N=79) were exposed, in the dark, to 60--90 minutes of cross-coupled rotations, combinations of pitch (or roll) and yaw rotation, while binocular horizontal, vertical, and torsional eye position were determined using infrared video-oculography. Centripetal acceleration in combination with angular cross-coupling was also studied. Simultaneous sinusoidal rotations in two planes (yaw with roll or pitch) provided a net symmetrical stimulus for the right and left labyrinths. In contrast, a constant velocity yaw rotation during sinusoidal roll or pitch provided the asymmetric stimulus model for AG. We found orthogonally oriented half-cycle VOR gain changes. The results depended on the direction of horizontal rotation during asymmetrical cross-coupling, and other aspects of the stimulus, including the phase relationship between the two rotational inputs, the symmetry of the stimulus, and training. Fos expression also revealed laterality differences in the prepositus and inferior olivary C subnucleus. In contrast the inferior olivary beta and ventrolateral outgrowth were labeled bilaterally. Additional cross-coupling dependent labeling was found in the flocculus, hippocampus, and several cortical regions, including the perirhinal and temporal association cortices. Analyses showed significant differences across the brain regions for several factors (symmetry, rotation velocity and direction, the presence of centripetal acceleration or a visual surround, and training). Finally, animals compensating from a unilateral surgical labyrinthectomy who received multiple cross-coupling training sessions had improved half-cycle VOR gain in the ipsilateral eye with head rotation toward the intact

  3. Ethics control of vertebrate animals experiments in biosatellite BION-M1 project

    NASA Astrophysics Data System (ADS)

    Ilyin, Eugene

    During April 19-May 19, 2013 it was realized 30-days flight of Russian biosatellite Bion-M1. The main goal of this flight was to study effects of microgravity upon behavior and structural-functional state of different physiological systems of vertebrates. The folloving species were accommodated aboard of biosatellite: 45 mice C57bl/6, 8 Mongolian gerbils Meriones unguiculatus, 15 lizards, i.e. geckos Chondrodctylus turneri Gray, and fish Oreochromis mossambicus. The selection and traing of mice for the flight and ground-based control experiments was carried out at the Research Institute of Mitoengineering by Moscow State University. The protocols for animals care and reserch were revised and adopted by Bioethics Commission of above mentioned institute (decision on November 01, 2013, N35). The final version of Bion-M1 Scientific Reseach Program and protocols for separate experiments were discussed and adopted by Biomedical Ethics Commission of Institute of Biomedical Problems (decision on April 4, 2014, N317). The IMBP Commission has a status of Physiological Section of Russian Bioethics Committee by Russian Commision for UNESCO affairs and follows the Russian Bioethical Guidelines for Experiments in Aerospace and Naval Medicine and other national and international rules including COSPAR International Policy and Guidelines for Animal Care and Use in Space-born Research. Because US-scientists were the main partners in mice investigations the decision of IMBP Biomedical Commission related to Bion-M1 project was sended for information to Institutional Animal Care and Use Committee of NASA Ames Research Center. Postflight estimation of mice was done by Russian veterinary with the participation of NASA Chief veterinary.

  4. Neuroprotective effects of pterin-6-aldehyde in gerbil global brain ischemia: comparison with those of alpha-phenyl-N-tert-butyl nitrone.

    PubMed

    Mori, H; Arai, T; Ishii, H; Adachi, T; Endo, N; Makino, K; Mori, K

    1998-01-30

    The superoxide (O2.-) scavenging activity and the neuroprotective effects of pterin-6-aldehyde (P6A), a xanthine oxidase inhibitor, were examined and compared with those of alpha-phenyl-N-tert-butyl nitrone (PBN), a spin trapping agent. The scavenging activity of P6A was more potent than that of PBN by 150-fold in neutrophil/phorbol myristate acetate O2.- generating system. P6A attenuated the neuronal damage with a much smaller dose and a greater efficiency than PBN in global brain ischemia in gerbils. These findings suggest that P6A is a more potent neuroprotective agent than PBN and has possible therapeutic effects against various diseases in which O2.- is involved. PMID:9507930

  5. Modified temporal-phase-unwrapping method for measuring in real time the out-of-plane displacements of the tympanic membrane of Mongolian Gerbil

    NASA Astrophysics Data System (ADS)

    Martínez-Celorio, R. A.; Dirckx, Joris J. J.; Buytaert, Jan A. N.; Martí-López, Luis; Decraemer, Wim

    2008-12-01

    A technique for measuring in real-time continuous out-of-plane displacements of delicate objects is proposed, and demonstrated on the tympanic membrane of Mongolian Gerbil. The technique is based on the combination of two methods: the spatial phase shifting (SPS) and the modified temporal phase unwrapping (TPU). The combination allows to obtain, in several steps, the phase values of the points that undergo out-of-plane displacement as the object is deformed. The technique reduces the frame acquisition time of the standard TPU used in moiré interferometry by a factor of 4, which is important to diminish post-mortem artifacts during in-vitro experiments and to reduce motion artifacts in in-vivo tests. The proposed technique is robust against problems associated with the temporal phase-shifting method, such as nonlinear phase shift and noise. The advantages and disadvantages are discussed.

  6. Sweet potato beta-carotene bioefficacy is enhanced by dietary fat and not reduced by soluble fiber intake in Mongolian gerbils.

    PubMed

    Mills, Jordan P; Tumuhimbise, Gaston A; Jamil, Kazi M; Thakkar, Sagar K; Failla, Mark L; Tanumihardjo, Sherry A

    2009-01-01

    Orange-fleshed sweet potato (OFSP) is an important source of beta-carotene (betaC). Provitamin A bioefficacy from plant foods is influenced by dietary fat and fiber. We fed 3% OFSP powder diets with varying amounts of fat and soluble fiber to vitamin A (VA)-depleted Mongolian gerbils (n = 85) for 3 wk (8 groups, n = 10/group; control, n = 9) following a baseline kill (n = 6). OFSP diets differing in fat (3, 6, and 12%) contained 0.24% soluble fiber. Two additional 3% OFSP diets contained 6% fat and 3 or 9% white-fleshed sweet potato (WFSP) powder with soluble fiber contents of 0.42 and 0.80%, respectively. Control, VA-, and betaC-supplemented groups were included. Simulated digestion experiments compared the bioaccessibility of betaC from boiled vs. oil stir-fried OFSP. All OFSP diets maintained VA status and 12% fat and WFSP-added diets improved VA status above baseline (P < 0.05). Bioefficacy, as bioconversion factors, in gerbils fed 12% fat (3.5 +/- 1.4 microg betaC:1 microg VA) was improved over the 3% fat and betaC groups (6.5 +/- 3.7 and 6.7 +/- 3.7 microg betaC:1 microg VA, respectively) (P < 0.05) but did not differ from WFSP-added groups or the 6% fat group with no WFSP. Stir-frying doubled the efficiency of betaC incorporation into micelles during small intestinal digestion in support of the stimulatory effect of dietary fat on bioefficacy in vivo. Soluble fiber intake derived from WFSP did not influence bioefficacy. Replacing WFSP with OFSP will affect VA status if adopted by target groups. PMID:19056651

  7. Difference in transient ischemia-induced neuronal damage and glucose transporter-1 immunoreactivity in the hippocampus between adult and young gerbils

    PubMed Central

    Park, Seung Min; Lee, Jae-Chul; Chen, Bai Hui; Shin, Bich-Na; Cho, Jeong Hwi; Kim, In Hye; Park, Joon Ha; Won, Moo-Ho; Ahn, Ji Hyeon; Tae, Hyun-Jin; Shin, Myoung Cheol; Park, Chan Woo; Cho, Jun Hwi; Lee, Hui Young

    2016-01-01

    Objective(s): The alteration of glucose transporters is closely related with the pathogenesis of brain edema. We compared neuronal damage/death in the hippocampus between adult and young gerbils following transient cerebral ischemia/reperfusion and changes of glucose transporter-1(GLUT-1)-immunoreactive microvessels in their ischemic hippocampal CA1 region. Materials and Methods: Transient cerebral ischemia was developed by 5-min occlusion of both common carotid arteries. Neuronal damage was examined by cresyl violet staining, NeuN immunohistochemistry and Fluoro-Jade B histofluorescence staining and changes in GLUT-1 expression was carried out by immunohistochemistry. Results: About 90% of pyramidal neurons only in the adult CA1 region were damaged after ischemia/reperfusion; in the young, about 53 % of pyramidal neurons were damaged from 7 days after ischemia/reperfusion. The density of GLUT-1-immunoreactive microvessels was significantly higher in the young sham-group than that in the adult sham-group. In the ischemia-operated-groups, the density of GLUT-1-immunoreactive microvessels was significantly decreased in the adult and young at 1 and 4 days post-ischemia, respectively, thereafter, the density of GLUT-1-immunoreactive microvessels was gradually increased in both groups after ischemia/reperfusion. Conclusion: CA1 pyramidal neurons of the young gerbil were damaged much later than that in the adult and that GLUT-1-immunoreactive microvessels were significantly decreased later in the young. These data indicate that GLUT-1 might differently contribute to neuronal damage according to age after ischemic insults. PMID:27403259

  8. Effect of atropine and gammahydroxybutyrate on ischemically induced changes in the level of radioactivity in (/sup 3/H)inositol phosphates in gerbil brain in vivo

    SciTech Connect

    Wikiel, H.; Halat, G.; Strosznajder, J.

    1988-05-01

    Brain ischemia in gerbils was induced by ligation of both common carotid arteries for 1 min or 10 min. Sham-operated animals served as controls. Intracerebral injection of (3H)inositol into gerbil brain 16 hr before ischemic insult resulted in equilibration of the label between inositol lipids and water-soluble inositol phosphate. A short ischemic period (1 min) resulted in a statistically significant increase in the radioactivity of inositol triphosphate (IP3) and inositol monophosphate (IP), by about 48% and 79%, respectively, with little change in that of the intermediate inositol biphosphate (IP2), which increased by about 16%. When the ischemic period was prolonged (10 min), an increase in the radioactivity of inositol monophosphate exclusively, by about 84%, was observed. The level of radioactivity in inositol phosphates IP2 and IP3 decreased by about 50%, probably as a consequence of phosphatase activation by the ischemic insult. The agonist of the cholinergic receptor, carbachol, injected intracerebrally (40 micrograms per animal) increased accumulation of radioactivity in all inositol phosphates. The level of radioactivity in IP3, IP2, and IP was elevated by about 40, 23, and 147%, respectively. The muscarinic cholinergic antagonist, atropine, injected intraperitoneally in doses of 100 mg/kg body wt. depressed phosphoinositide metabolism in control animals. The level of radioactivity in water-soluble inositol metabolites in the brain of animals pretreated with atropine was evidently about 32% lower than in untreated animals. Pretreatment with atropine decreased the radioactivity of all inositol phosphates in the brain of animals subjected to 1-min ischemia and the radioactivity of IP in the case of 10-min brain ischemia.

  9. Ebselen pretreatment attenuates ischemia/reperfusion injury and prevents hyperglycemia by improving hepatic insulin signaling and β-cell survival in gerbils.

    PubMed

    Park, S; Kang, S; Kim, D S; Shin, B K; Moon, N R; Daily, J W

    2014-08-01

    Transient carotid artery occlusion causes ischemia/reperfusion (I/R) injury resulting in neuron and pancreatic β-cell death with consequential post-stroke hyperglycemia, which can lead to diabetes and may accelerate the development of Alzheimer's disease. Antioxidants have been shown to protect against the I/R injury and destruction of neurons. However, it is unknown whether the protection against I/R injury extends to the pancreatic β-cells. Therefore, we investigated whether treatment with ebselen, a glutathione peroxidase mimic, prevents neuronal and β-cell death following I/R in gerbils susceptible to stroke. After 28 days post artery occlusion, there was widespread neuronal cell death in the CA1 of the hippocampus and elevated IL-1β and TNF-α levels. Pretreatment with ebselen prevented the death by 56% and attenuated neurological damage (abnormal eyelid drooping, hair bristling, muscle tone, flexor reflex, posture, and walking patterns). Ischemic gerbils also exhibited impaired glucose tolerance and insulin sensitivity which induced post-stroke hyperglycemia associated with decreased β-cell mass due to increased β-cell apoptosis. Ebselen prevented the increased β-cell apoptosis, possibly by decreasing IL-1β and TNF-α in islets. Ischemia also attenuated hepatic insulin signaling, and expression of GLUT2 and glucokinase, whereas ebselen prevented the attenuation and suppressed gluconeogenesis by decreasing PEPCK expression. In conclusion, antioxidant protection by ebselen attenuated I/R injury of neurons and pancreatic β-cells and prevented subsequent impairment of glucose regulation that could lead to diabetes and Alzheimer's disease. PMID:24807533

  10. Helicobacter pylori eradication by sitafloxacin-lansoprazole combination and sitafloxacin pharmacokinetics in Mongolian gerbils and its in vitro activity and resistance development.

    PubMed

    Yamamoto, Tatsuo; Takano, Tomomi; Higuchi, Wataru; Nishiyama, Akihito; Taneike, Ikue; Yoshida, Kumi; Kanda, Hiroko; Imamura, Yuichiro

    2011-09-01

    A total of 293 strains of Helicobacter pylori, including strains resistant to levofloxacin, clarithromycin, metronidazole, or amoxicillin, were examined for in vitro susceptibility to 10 antimicrobial agents. Among these agents, sitafloxacin (a fluoroquinolone) showed the greatest activity (MIC(90), 0.06 μg/ml), with high bactericidal activity and synergy in sitafloxacin-lansoprazole (a proton pump inhibitor) combination. In a Mongolian gerbil model with a H. pylori ATCC 43504 challenge, marked eradication effects were observed at ≥1 mg/kg for sitafloxacin, ≥10 mg/kg for levofloxacin, and ≥10 mg/kg for lansoprazole, reflecting MIC levels for each agent (0.008, 0.25, and 2 μg/ml, respectively). The therapeutic rates were 83.3% for the sitafloxacin (0.3 mg/kg)-lansoprazole (2.5 mg/kg) combination and 0% for either sitafloxacin or lansoprazole alone. The maximum serum concentration (C(max)) of sitafloxacin was 0.080 ± 0.054 μg/ml at 30 min, when orally administered at 1 mg/kg. The simultaneous administration of lansoprazole resulted in no difference. In the resistance development assay, MICs of levofloxacin increased 64- to 256-fold with gyrA mutations (Ala88Pro and Asn87Lys), while MICs of sitafloxacin only up to 16-fold with the Asn87Lys mutation. The data suggest that sitafloxacin exhibited superior anti-H. pylori activity with low rates of resistance development in vitro and that, reflecting high in vitro activities, sitafloxacin-lansoprazole combination exhibited strong therapeutic effects in Mongolian gerbils with a C(max) of sitafloxacin that was 10-fold higher than the MIC value at a 1-mg/kg administration. PMID:21730117

  11. Effects of ischemic preconditioning on VEGF and pFlk-1 immunoreactivities in the gerbil ischemic hippocampus after transient cerebral ischemia.

    PubMed

    Park, Yoo Seok; Cho, Jun Hwi; Kim, In Hye; Cho, Geum-Sil; Cho, Jeong-Hwi; Park, Joon Ha; Ahn, Ji Hyeon; Chen, Bai Hui; Shin, Bich-Na; Shin, Myoung Cheol; Tae, Hyun-Jin; Cho, Young Shin; Lee, Yun Lyul; Kim, Young-Myeong; Won, Moo-Ho; Lee, Jae-Chul

    2014-12-15

    Ischemia preconditioning (IPC) displays an important adaptation of the CNS to sub-lethal ischemia. In the present study, we examined the effect of IPC on immunoreactivities of VEGF-, and phospho-Flk-1 (pFlk-1) following transient cerebral ischemia in gerbils. The animals were randomly assigned to four groups (sham-operated-group, ischemia-operated-group, IPC plus (+) sham-operated-group, and IPC+ischemia-operated-group). IPC was induced by subjecting gerbils to 2 min of ischemia followed by 1 day of recovery. In the ischemia-operated-group, a significant loss of neurons was observed in the stratum pyramidale (SP) of the hippocampal CA1 region (CA1) alone 5 days after ischemia-reperfusion, however, in all the IPC+ischemia-operated-groups, pyramidal neurons in the SP were well protected. In immunohistochemical study, VEGF immunoreactivity in the ischemia-operated-group was increased in the SP at 1 day post-ischemia and decreased with time. Five days after ischemia-reperfusion, strong VEGF immunoreactivity was found in non-pyramidal cells, which were identified as pericytes, in the stratum oriens (SO) and radiatum (SR). In the IPC+sham-operated- and IPC+ischemia-operated-groups, VEGF immunoreactivity was significantly increased in the SP. pFlk-1 immunoreactivity in the sham-operated- and ischemia-operated-groups was hardly found in the SP, and, from 2 days post-ischemia, pFlk-1 immunoreactivity was strongly increased in non-pyramidal cells, which were identified as pericytes. In the IPC+sham-operated-group, pFlk-1 immunoreactivity was significantly increased in both pyramidal and non-pyramidal cells; in the IPC+ischemia-operated-groups, the similar pattern of VEGF immunoreactivity was found in the ischemic CA1, although the VEGF immunoreactivity was strong in non-pyramidal cells at 5 days post-ischemia. In brief, our findings show that IPC dramatically augmented the induction of VEGF and pFlk-1 immunoreactivity in the pyramidal cells of the CA1 after ischemia

  12. Age-dependent changes in the protein expression levels of Redd1 and mTOR in the gerbil hippocampus during normal aging

    PubMed Central

    CHOI, HEE-SOO; AHN, JI HYEON; PARK, JOON HA; WON, MOO-HO; LEE, CHOONG-HYUN

    2016-01-01

    Redd1, also known as RTP801/Dig2/DDIT4, is a stress-induced protein and a negative regulator of mammalian target of rapamycin (mTOR). Redd1 is also closely associated with oxidative stress and DNA damage. In the present study, age-related changes in the protein expression levels of mTOR and Redd1 were investigated using immunohistochemistry and western blot in the gerbil hippocampus at postnatal month (PM) 3, 6, 12 and 24. No significant differences were identified in the levels of mTOR among the experimental groups, whereas, the levels of phosphorylated mTOR decreased with age. The protein expression levels of Redd1 were observed to gradually increase with age; in the PM 24 group, the level was significantly increased (~189.2%), compared with the PM 3 group. In addition, Redd1 immunoreactivity was significantly increased in the hippocampal principal neurons of the PM 24 group, including the pyramidal cells in the hippocampus proper and granule cells in the dentate gyrus, compared with the other experimental groups. These results demonstrated that the protein expression of Redd1 in the hippocampus was markedly increased during normal aging, indicating that the age-related increase in the expression of Redd1 may be closely associated with age-related hippocampal change. PMID:26846432

  13. Burst activity and ultrafast activation kinetics of CaV1.3 Ca2+ channels support presynaptic activity in adult gerbil hair cell ribbon synapses

    PubMed Central

    Zampini, Valeria; Johnson, Stuart L; Franz, Christoph; Knipper, Marlies; Holley, Matthew C; Magistretti, Jacopo; Masetto, Sergio; Marcotti, Walter

    2013-01-01

    Auditory information transfer to afferent neurons relies on precise triggering of neurotransmitter release at the inner hair cell (IHC) ribbon synapses by Ca2+ entry through CaV1.3 Ca2+ channels. Despite the crucial role of CaV1.3 Ca2+ channels in governing synaptic vesicle fusion, their elementary properties in adult mammals remain unknown. Using near-physiological recording conditions we investigated Ca2+ channel activity in adult gerbil IHCs. We found that Ca2+ channels are partially active at the IHC resting membrane potential (−60 mV). At −20 mV, the large majority (>70%) of Ca2+ channel first openings occurred with an estimated delay of about 50 μs in physiological conditions, with a mean open time of 0.5 ms. Similar to other ribbon synapses, Ca2+ channels in IHCs showed a low mean open probability (0.21 at −20 mV), but this increased significantly (up to 0.91) when Ca2+ channel activity switched to a bursting modality. We propose that IHC Ca2+ channels are sufficiently rapid to transmit fast signals of sound onset and support phase-locking. Short-latency Ca2+ channel opening coupled to multivesicular release would ensure precise and reliable signal transmission at the IHC ribbon synapse. PMID:23713031

  14. Age-dependent changes in the protein expression levels of Redd1 and mTOR in the gerbil hippocampus during normal aging.

    PubMed

    Choi, Hee-Soo; Ahn, Ji Hyeon; Park, Joon Ha; Won, Moo-Ho; Lee, Choong-Hyun

    2016-03-01

    Redd1, also known as RTP801/Dig2/DDIT4, is a stress-induced protein and a negative regulator of mammalian target of rapamycin (mTOR). Redd1 is also closely associated with oxidative stress and DNA damage. In the present study, age‑related changes in the protein expression levels of mTOR and Redd1 were investigated using immunohistochemistry and western blot in the gerbil hippocampus at postnatal month (PM) 3, 6, 12 and 24. No significant differences were identified in the levels of mTOR among the experimental groups, whereas, the levels of phosphorylated mTOR decreased with age. The protein expression levels of Redd1 were observed to gradually increase with age; in the PM 24 group, the level was significantly increased (~189.2%), compared with the PM 3 group. In addition, Redd1 immunoreactivity was significantly increased in the hippocampal principal neurons of the PM 24 group, including the pyramidal cells in the hippocampus proper and granule cells in the dentate gyrus, compared with the other experimental groups. These results demonstrated that the protein expression of Redd1 in the hippocampus was markedly increased during normal aging, indicating that the age-related increase in the expression of Redd1 may be closely associated with age-related hippocampal change. PMID:26846432

  15. Ischemia-Induced Changes of PRAS40 and p-PRAS40 Immunoreactivities in the Gerbil Hippocampal CA1 Region After Transient Cerebral Ischemia.

    PubMed

    Park, Joon Ha; Shin, Bich Na; Ahn, Ji Hyeon; Cho, Jeong-Hwi; Kim, In Hye; Kim, Dae Won; Won, Moo-Ho; Hong, Seongkweon; Cho, Jun Hwi; Lee, Choong-Hyun

    2016-07-01

    Proline-rich Akt substrate of 40-kDa (PRAS40) is one of the important interactive linkers between Akt and mTOR signaling pathways. The increase of PRAS40 is related with the reduction of brain damage induced by cerebral ischemia. In the present study, we investigated time-dependent changes in PRAS40 and phospho-PRAS40 (p-PRAS40) immunoreactivities in the hippocampal CA1 region of the gerbil after 5 min of transient cerebral ischemia. PRAS40 immunoreactivity in the CA1 region was decreased in pyramidal neurons from 12 h after ischemic insult in a time-dependent manner, and, at 5 days post-ischemia, PRAS40 immunoreactivity was newly expressed in astrocytes. p-PRAS40 immunoreactivity in the CA1 pyramidal neurons was hardly found 12 h and apparently detected again 1 and 2 days after ischemic insult. At 5 days post-ischemia, p-PRAS40 immunoreactivity in the CA1 pyramidal neurons was not found. These results indicate that ischemia-induced changes in PRAS40 and p-PRAS40 immunoreactivities in CA1 pyramidal neurons and astrocytes may be closely associated with delayed neuronal death in the hippocampal CA1 region following transient cerebral ischemia. PMID:26526334

  16. Ethanol and isopropanol in concentrations present in hand sanitizers sharply reduce excystation of Giardia and Entamoeba and eliminate oral infectivity of Giardia cysts in gerbils.

    PubMed

    Chatterjee, Aparajita; Bandini, Giulia; Motari, Edwin; Samuelson, John

    2015-11-01

    Enteric protozoan parasites, which are spread by the fecal-oral route, are important causes of diarrhea (Giardia duodenalis) and amebic dysentery (Entamoeba histolytica). Cyst walls of Giardia and Entamoeba have a single layer composed of fibrils of β-1,3-linked GalNAc and β-1,4-linked GlcNAc (chitin), respectively. The goal here was to determine whether hand sanitizers that contain ethanol or isopropanol as the active microbicide might reduce transmission of these parasites. We found that treatment with these alcohols with or without drying in a rotary evaporator (to model rapid evaporation of sanitizers on hands) kills 85 to 100% of cysts of G. duodenalis and 90 to 100% of cysts of Entamoeba invadens (a nonpathogenic model for E. histolytica), as shown by nuclear labeling with propidium iodide and failure to excyst in vitro. Alcohols with or without drying collapsed the cyst walls of Giardia but did not collapse the cyst walls of Entamoeba. To validate the in vitro results, we showed that treatment with alcohols eliminated oral infection of gerbils by 1,000 G. duodenalis cysts, while a commercial hand sanitizer (Purell) killed E. invadens cysts that were directly applied to the hands. These results suggest that expanded use of alcohol-based hand sanitizers might reduce the transmission of Giardia and Entamoeba. PMID:26282413

  17. Ethanol and Isopropanol in Concentrations Present in Hand Sanitizers Sharply Reduce Excystation of Giardia and Entamoeba and Eliminate Oral Infectivity of Giardia Cysts in Gerbils

    PubMed Central

    Chatterjee, Aparajita; Bandini, Giulia; Motari, Edwin

    2015-01-01

    Enteric protozoan parasites, which are spread by the fecal-oral route, are important causes of diarrhea (Giardia duodenalis) and amebic dysentery (Entamoeba histolytica). Cyst walls of Giardia and Entamoeba have a single layer composed of fibrils of β-1,3-linked GalNAc and β-1,4-linked GlcNAc (chitin), respectively. The goal here was to determine whether hand sanitizers that contain ethanol or isopropanol as the active microbicide might reduce transmission of these parasites. We found that treatment with these alcohols with or without drying in a rotary evaporator (to model rapid evaporation of sanitizers on hands) kills 85 to 100% of cysts of G. duodenalis and 90 to 100% of cysts of Entamoeba invadens (a nonpathogenic model for E. histolytica), as shown by nuclear labeling with propidium iodide and failure to excyst in vitro. Alcohols with or without drying collapsed the cyst walls of Giardia but did not collapse the cyst walls of Entamoeba. To validate the in vitro results, we showed that treatment with alcohols eliminated oral infection of gerbils by 1,000 G. duodenalis cysts, while a commercial hand sanitizer (Purell) killed E. invadens cysts that were directly applied to the hands. These results suggest that expanded use of alcohol-based hand sanitizers might reduce the transmission of Giardia and Entamoeba. PMID:26282413

  18. [Taxonomic status of the Chim virus (CHIMV) (Bunyaviridae, Nairovirus, Qalyub group) isolated from the Ixodidae and Argasidae ticks collected in the great gerbil (Rhombomys opimus Lichtenstein, 1823) (Muridae, Gerbillinae) burrows in Uzbekistan and Kazakhstan].

    PubMed

    L'vov, D K; Al'khovskiĭ, S V; Shchelkanov, M Iu; Shchetinin, A M; Aristova, V A; Morozova, T N; Gitel'man, A K; Deriabin, P G; Botikov, A G

    2014-01-01

    Full-length genome of the Chim virus (CHIMV) (strain LEIV-858Uz) was sequenced using the next-generation sequencing approach (ID GenBank: KF801656). The CHIMV/LEIV-858Uz was isolated from the Ornithodoros tartakovskyi Olenev, 1931 ticks collected in the great gerbil (Rhombomys opimus Lichtenstein, 1823) burrow in Uzbekistan near Chim town (Kashkadarinsky region) in July of 1971. Later, four more CHIMV strains were isolated from the O. tartakovskyi, O. papillipes Birula, 1895, Rhipicephalus turanicus Pomerantsev, 1936 collected in the great gerbil burrows in Kashkadarinsky, Bukhara, and Syrdarya regions of Uzbekistan, and three strains--from the Hyalomma asiaticum Schulze et Schlottke, 1930 from the great gerbil burrows in Dzheskazgan region of Kazakhstan. The virus is a potential pathogen of humans and camels. The phylogenetic analysis revealed that the CHIMV is a novel member of the Nairovirus genus (Bunyaviridae) and closely related to the Qalyub virus (QYBV), which is prototype for the group of the same name. The amino acid homology between the CHIMV and QYBV is 87% for the RdRp catalytic center (L-segment) that is coincident with both QYBV and CHIMV associated with the Ornithodoros ticks and burrow of rodents as well. The CHIMV homologies with other nairoviruses are 30-40% for the amino acid sequences of precursor polyprotein GnGc (M-segment), whereas 50%--for the nucleocapsid N (S-segment). The data obtained permit to classify the CHIMV as a member of the QYBV group in the genus of Nairovirus (Bunyaviridae). PMID:25335414

  19. Intense and specialized dendritic localization of the fragile X mental retardation protein in binaural brainstem neurons: a comparative study in the alligator, chicken, gerbil, and human.

    PubMed

    Wang, Yuan; Sakano, Hitomi; Beebe, Karisa; Brown, Maile R; de Laat, Rian; Bothwell, Mark; Kulesza, Randy J; Rubel, Edwin W

    2014-06-15

    Neuronal dendrites are structurally and functionally dynamic in response to changes in afferent activity. The fragile X mental retardation protein (FMRP) is an mRNA binding protein that regulates activity-dependent protein synthesis and morphological dynamics of dendrites. Loss and abnormal expression of FMRP occur in fragile X syndrome (FXS) and some forms of autism spectrum disorders. To provide further understanding of how FMRP signaling regulates dendritic dynamics, we examined dendritic expression and localization of FMRP in the reptilian and avian nucleus laminaris (NL) and its mammalian analogue, the medial superior olive (MSO), in rodents and humans. NL/MSO neurons are specialized for temporal processing of low-frequency sounds for binaural hearing, which is impaired in FXS. Protein BLAST analyses first demonstrate that the FMRP amino acid sequences in the alligator and chicken are highly similar to human FMRP with identical mRNA-binding and phosphorylation sites, suggesting that FMRP functions similarly across vertebrates. Immunocytochemistry further reveals that NL/MSO neurons have very high levels of dendritic FMRP in low-frequency hearing vertebrates including alligator, chicken, gerbil, and human. Remarkably, dendritic FMRP in NL/MSO neurons often accumulates at branch points and enlarged distal tips, loci known to be critical for branch-specific dendritic arbor dynamics. These observations support an important role for FMRP in regulating dendritic properties of binaural neurons that are essential for low-frequency sound localization and auditory scene segregation, and support the relevance of studying this regulation in nonhuman vertebrates that use low frequencies in order to further understand human auditory processing disorders. PMID:24318628

  20. A small, new gerbil-mouse Eligmodontia (Rodentia: Cricetidae) from dunes at the coasts and deserts of north-central Chile: molecular, chromosomic, and morphological analyses.

    PubMed

    Spotorno, Angel E; Zuleta, Carlos; Walker, Laura I; Manriquez, German; Valladares, Pablo; Marin, Juan C

    2013-01-01

    A small, new species of gerbil rodents of the genus Eligmodontia from the southwestern dunes of the Atacama Desert in northern Chile is described; the genus had not been reported for this western lowland region. Our description is based on cytogenetic and molecular data, as well as cranial and external morphology. In order to support this hypothesis, we studied 27 specimens captured in Playa Los Choros (Coquimbo) and Copiapó (Atacama), comparing them with samples of all the extant species of the genus. Nineteen individuals consistently showed 2N=50, FN=48, with telocentric chromosomes and G-bands identical to those of the geographically northeastern E. hirtipes; these two groups were geographically separated by E. puerulus (2N = 34, FN = 48). The phylogenetic analysis of 56 Eligmodontia cytochrome-b gene sequences yielded a maximum-likelihood phylogenetic tree where the new species formed a divergent and well-supported clade within the genus, which was also confirmed by unweighted parsimony, minimum evolution, and Bayesian analyses. The new species has K2P genetic distances of 12.8% from the geographically distant E. hirtipes, and 10.3% from E. puerulus. Axes 1 and 2 of Principal Component Analysis based on 12 body and skull measurements clearly separated the new species, the latter having a smaller head+body length (70.6 +/- 3.4 mm, n = 17) and lower weight (11.9 +/- 1.9 g, n = 20). We provide strong evidence to recognize a distinct new western lineage within Eligmodontia genus, Eligmodontia dunaris sp. nov., for which we give a complete taxonomic description and a hypothetical biogeographic scenario. The new species should be considered endangered, due to its level of endemism, its low population numbers (which can be occasionally increased after a blooming desert) and its fragile dry habitat patchily distributed near the Atacama Desert. PMID:25250459

  1. Time- and cell-type specific changes in iron, ferritin, and transferrin in the gerbil hippocampal CA1 region after transient forebrain ischemia

    PubMed Central

    Yoo, Dae Young; Yoo, Ki-Yeon; Park, Joon Ha; Kwon, Hyun Jung; Jung, Hyo Young; Kim, Jong Whi; Choi, Goang-Min; Moon, Seung Myung; Kim, Dae Won; Yoon, Yeo Sung; Won, Moo-Ho; Hwang, In Koo

    2016-01-01

    In the present study, we used immunohistochemistry and western blot analysis to examine changes in the levels and cellular localization of iron, heavy chain ferritin (ferritin-H), and transferrin in the gerbil hippocampal CA1 region from 30 minutes to 7 days following transient forebrain ischemia. Relative to sham controls, iron reactivity increased significantly in the stratum pyramidale and stratum oriens at 12 hours following ischemic insult, transiently decreased at 1–2 days and then increased once again within the CA1 region at 4–7 days after ischemia. One day after ischemia, ferritin-H immunoreactivity increased significantly in the stratum pyramidale and decreased at 2 days. At 4–7 days after ischemia, ferritin-H immunoreactivity in the glial components in the CA1 region was significantly increased. Transferrin immunoreactivity was increased significantly in the stratum pyramidale at 12 hours, peaked at 1 day, and then decreased significantly at 2 days after ischemia. Seven days after ischemia, Transferrin immunoreactivity in the glial cells of the stratum oriens and radiatum was significantly increased. Western blot analyses supported these results, demonstrating that compared to sham controls, ferritin H and transferrin protein levels in hippocampal homogenates significantly increased at 1 day after ischemia, peaked at 4 days and then decreased. These results suggest that iron overload-induced oxidative stress is most prominent at 12 hours after ischemia in the stratum pyramidale, suggesting that this time window may be the optimal period for therapeutic intervention to protect neurons from ischemia-induced death. PMID:27482220

  2. NMDA currents modulate the synaptic input-output functions of neurons in the dorsal nucleus of the lateral lemniscus in Mongolian gerbils.

    PubMed

    Porres, Christian P; Meyer, Elisabeth M M; Grothe, Benedikt; Felmy, Felix

    2011-03-23

    Neurons in the dorsal nucleus of the lateral lemniscus (DNLL) receive excitatory and inhibitory inputs from the superior olivary complex (SOC) and convey GABAergic inhibition to the contralateral DNLL and the inferior colliculi. Unlike the fast glycinergic inhibition in the SOC, this GABAergic inhibition outlasts auditory stimulation by tens of milliseconds. Two mechanisms have been postulated to explain this persistent inhibition. One, an "integration-based" mechanism, suggests that postsynaptic excitatory integration in DNLL neurons generates prolonged activity, and the other favors the synaptic time course of the DNLL output itself. The feasibility of the integration-based mechanism was tested in vitro in DNLL neurons of Mongolian gerbils by quantifying the cellular excitability and synaptic input-output functions (IO-Fs). All neurons were sustained firing and generated a near monotonic IO-F on current injections. From synaptic stimulations, we estimate that activation of approximately five fibers, each on average liberating ∼18 vesicles, is sufficient to trigger a single postsynaptic action potential. A strong single pulse of afferent fiber stimulation triggered multiple postsynaptic action potentials. The steepness of the synaptic IO-F was dependent on the synaptic NMDA component. The synaptic NMDA receptor current defines the slope of the synaptic IO-F by enhancing the temporal and spatial EPSP summation. Blocking this NMDA-dependent amplification during postsynaptic integration of train stimulations resulted into a ∼20% reduction of the decay time course of the GABAergic inhibition. Thus, our data show that the NMDA-dependent amplification of the postsynaptic activity contributes to the GABAergic persistent inhibition generated by DNLL neurons. PMID:21430152

  3. Fine Tuning of CaV1.3 Ca2+ Channel Properties in Adult Inner Hair Cells Positioned in the Most Sensitive Region of the Gerbil Cochlea

    PubMed Central

    Zampini, Valeria; Johnson, Stuart L.; Franz, Christoph; Knipper, Marlies; Holley, Matthew C.; Magistretti, Jacopo; Russo, Giancarlo; Marcotti, Walter; Masetto, Sergio

    2014-01-01

    Hearing relies on faithful signal transmission by cochlear inner hair cells (IHCs) onto auditory fibres over a wide frequency and intensity range. Exocytosis at IHC ribbon synapses is triggered by Ca2+ inflow through CaV1.3 (L-type) Ca2+ channels. We investigated the macroscopic (whole-cell) and elementary (cell-attached) properties of Ca2+ currents in IHCs positioned at the middle turn (frequency ∼2 kHz) of the adult gerbil cochlea, which is their most sensitive hearing region. Using near physiological recordings conditions (body temperature and a Na+ based extracellular solution), we found that the macroscopic Ca2+ current activates and deactivates very rapidly (time constant below 1 ms) and inactivates slowly and only partially. Single-channel recordings showed an elementary conductance of 15 pS, a sub-ms latency to first opening, and a very low steady-state open probability (Po: 0.024 in response to 500-ms depolarizing steps at ∼−18 mV). The value of Po was significantly larger (0.06) in the first 40 ms of membrane depolarization, which corresponds to the time when most Ca2+ channel openings occurred clustered in bursts (mean burst duration: 19 ms). Both the Po and the mean burst duration were smaller than those previously reported in high-frequency basal IHCs. Finally, we found that middle turn IHCs are likely to express about 4 times more Ca2+ channels per ribbon than basal cells. We propose that middle-turn IHCs finely-tune CaV1.3 Ca2+ channel gating in order to provide reliable information upon timing and intensity of lower-frequency sounds. PMID:25409445

  4. Neuroprotection of Ischemic Preconditioning is Mediated by Anti-inflammatory, Not Pro-inflammatory, Cytokines in the Gerbil Hippocampus Induced by a Subsequent Lethal Transient Cerebral Ischemia.

    PubMed

    Kim, Dong Won; Lee, Jae-Chul; Cho, Jeong-Hwi; Park, Joon Ha; Ahn, Ji Hyeon; Chen, Bai Hui; Shin, Bich-Na; Tae, Hyun-Jin; Seo, Jeong Yeol; Cho, Jun Hwi; Kang, Il Jun; Hong, Seongkweon; Kim, Young-Myeong; Won, Moo-Ho; Kim, In Hye

    2015-09-01

    Ischemic preconditioning (IPC) induced by sublethal transient cerebral ischemia could reduce neuronal damage/death following a subsequent lethal transient cerebral ischemia. We, in this study, compared expressions of interleukin (IL)-2 and tumor necrosis factor (TNF)-α as pro-inflammatory cytokines, and IL-4 and IL-13 as anti-inflammatory cytokines in the gerbil hippocampal CA1 region between animals with lethal ischemia and ones with IPC followed by lethal ischemia. In the animals with lethal ischemia, pyramidal neurons in the stratum pyramidale (SP) of the hippocampal CA1 region were dead at 5 days post-ischemia; however, IPC protected the CA1 pyramidal neurons from lethal ischemic injury. Expressions of all cytokines were significantly decreased in the SP after lethal ischemia and hardly detected in the SP at 5 days post-ischemia because the CA1 pyramidal neurons were dead. IPC increased expressions of anti-inflammatory cytokines (IL-4 and IL-13) in the stratum pyramidale of the CA1 region following no lethal ischemia (sham-operation), and the increased expressions of IL-4 and IL-13 by IPC were continuously maintained is the SP of the CA1 region after lethal ischemia. However, pro-inflammatory cytokines (IL-2 and TNF-α) in the SP of the CA1 region were similar those in the sham-operated animals with IPC, and the IL-4 and IL-13 expressions in the SP were maintained after lethal ischemia. In conclusion, this study shows that anti-inflammatory cytokines significantly increased and longer maintained by IPC and this might be closely associated with neuroprotection after lethal transient cerebral ischemia. PMID:26290267

  5. BOLD effect: new aspects of the hemodynamic response through combination of fMRI and optical recording in the barrel cortex of the gerbil

    NASA Astrophysics Data System (ADS)

    Hess, Andreas; Stiller, Detelf; Scheich, Henning

    2000-04-01

    Functional MRI (fMRI) is a non-invasive technique widely used to map brain-functions. Nevertheless, its hemodynamic basis and spatial precision with which fMRI reflects sites of neuronal activity are not completely understood. We therefore combined fMRI, based on the blood oxygenation level dependent (BOLD) effect, with optical recording of intrinsic signals (ORIS), a technique, which has a better spatial and temporal resolution. Furthermore, ORIS can distinguish between localized changes in deoxyhemoglobin, and more widespread changes in cerebral blood volume/flow. In gerbils hemodynamic responses over the contralateral barrel cortex were studied with both methods, using identical stimulation of a single vibrissae and identical integration and correlation analysis strategies. Analysis of integration maps and of the spatial distribution and temporal correlation with the block-design of vibrissal stimulation revealed that the BOLD signal, at the site of neuronal activation, does not reflect a depletion of deoxyhemoglobin, as generally assumed. Instead, its positive polarity is likely due to an increase in cerebral blood volume (CBV) whose highly dynamic effect on the BOLD signal exceeds that of the increase in deoxyhemoglobin remaining elevated during prolonged stimulation. This is so, because we show, that blood flow does wash out deoxyhemoglobin but at a rate which is to decrease the deoxyhemoglobin concentration in the voxel below resting level. The wash out causes an accumulation of deoxyhemoglobin in the draining venous side, but at a time window which can be clearly distinguished from the specific activity by applying an analysis strategy based on correlation functions. Therefore, draining veins do not appear as confounding problem. This knowledge could be useful to model the BOLD effect more accurately and improve the spatial resolution of fMRI.

  6. Effect of ischemic preconditioning on the expression of c-myb in the CA1 region of the gerbil hippocampus after ischemia/reperfusion injury

    PubMed Central

    Lee, Hui Young; Tae, Hyun-Jin; Cho, Geum-Sil; Kim, In Hye; Cho, Jeong Hwi; Park, Joon Ha; Ahn, Ji Hyeon; Chen, Bai Hui; Shin, Bich-Na; Won, Moo-Ho; Park, Chan Woo; Cho, Jun Hwi; Seo, Jeong Yeol; Lee, Jae-Chul

    2016-01-01

    Objective(s): In the present study, we investigated the effect of ischemic preconditioning (IPC) on c-myb immunoreactivity as well as neuronal damage/death after a subsequent lethal transient ischemia in gerbils. Materials and Methods: IPC was subjected to a 2 min sublethal ischemia and a lethal transient ischemia was given 5 min transient ischemia. The animals in all of the groups were given recovery times of 1 day, 2 days and 5 days and we examined change in c-myb immunoreactivity as well as neuronal damage/death in the hippocampus induced by a lethal transient ischemia. Results: A lethal transient ischemia induced a significant loss of cells in the stratum pyramidale (SP) of the hippocampal CA1 region at 5 days post-ischemia, and this insult showed that c-myb immunoreactivity in cells of the SP of the CA1 region was significantly decreased at 2 days post-ischemia and disappeared at 5 days post-ischemia. However, IPC effectively prevented the neuronal loss in the SP and showed that c-myb immunoreactivity was constitutively maintained in the SP after a lethal transient ischemia. Conclusion: Our results show that a lethal transient ischemia significantly decreased c-myb immunoreactivity in the SP of the CA1 region and that IPC well preserved c-myb immunoreactivity in the SP of the CA1 region. We suggest that the maintenance of c-myb might be related with IPC-mediated neuroprotection after a lethal ischemic insult. PMID:27482343

  7. Molecular phylogeny of the subfamily Gerbillinae (Muridae, Rodentia) with emphasis on species living in the Xinjiang-Uygur Autonomous Region of China and based on the mitochondrial cytochrome b and cytochrome c oxidase subunit II genes.

    PubMed

    Ito, Mamoru; Jiang, Wei; Sato, Jun J; Zhen, Qiang; Jiao, Wei; Goto, Kazuo; Sato, Hiroshi; Ishiwata, Kenji; Oku, Yuzaburo; Chai, June-Jie; Kamiya, Haruo

    2010-03-01

    Rodents belonging to the subfamily Gerbillinae and living in the Xinjiang-Uygur autonomous region of China were collected in field surveys between 2001 and 2003. We found four Meriones species, including M. chengi M. liycus, M. meridianus, and M. tamariscinus, as well as related species from different genera, Rhombomys opimus and Brachiones przewaliskii For phylogenetic analyses of these gerbilline species, DNA sequences of parts of the mitochondrial cytochrome b (Cytb) and cytochrome c oxidase subunit II (COII) genes were examined with the neighbor Joining, maximum parsimony, maximum likelihood, and Bayesian inference methods. Our phylogenetic analyses suggest that the genus Meriones is not monophyletic and place M. tamaricinus as the sister taxon to a clade comprising Brachiones, Psammomys, Rhombomys, and the other Meriones species. The remaining Meriones species separate into three lineages: M. meridianus (including M. chengi), Meriones unguiculatus, and a clade that includes multiple Meriones species originating from Asia, the Middle East, and Africa. The phylogenetic relationships among the genera Brachines, Meriones, Psammomys, and Rhombomys remain ambiguous, probably due to the saturation of mutations that occurs in fast-evolving mitochondrial DNA. In addition, intraspecific variation was observed for M. meridianus, and this mostly correlated with collection localities, i.e., the northern and southern parts of the Xinjiang region. This variation corresponded to interspecific levels of divergence among other lineages of Meriones. Interestingly, no differences were observed in either the Cytb or COII gene sequences isolated from M. chengi collected from the Turfan Basin in the north and those from M. meridianus in the south, suggesting that M. chengi may be a synonym of M. meridianus. PMID:20192696

  8. 13C Natural Abundance of Serum Retinol Is a Novel Biomarker for Evaluating Provitamin A Carotenoid-Biofortified Maize Consumption in Male Mongolian Gerbils123

    PubMed Central

    Pungarcher, India; Mourao, Luciana; Davis, Christopher R; Simon, Philipp; Pixley, Kevin V; Tanumihardjo, Sherry A

    2016-01-01

    Background: Crops such as maize, sorghum, and millet are being biofortified with provitamin A carotenoids to ensure adequate vitamin A (VA) intakes. VA assessment can be challenging because serum retinol concentrations are homeostatically controlled and more sensitive techniques are resource-intensive. Objectives: We investigated changes in serum retinol relative differences of isotope amount ratios of 13C/12C (δ13C) caused by natural 13C fractionation in C3 compared with C4 plants as a biomarker to detect provitamin A efficacy from biofortified (orange) maize and high-carotene carrots. Methods: The design was a 2 × 2 × 2 maize (orange compared with white) by carrot (orange compared with white) by a VA fortificant (VA+ compared with VA−) in weanling male Mongolian gerbils (n = 55), which included a 14-d VA depletion period and a 62-d treatment period (1 baseline and 8 treatment groups; n = 5−7/group). Liver VA and serum retinol were quantified, purified by HPLC, and analyzed by GC combustion isotope ratio mass spectrometry for 13C. Results: Treatments affected liver VA concentrations (0.048 ± 0.039 to 0.79 ± 0.24 μmol/g; P < 0.0001) but not overall serum retinol concentrations (1.38 ± 0.22 μmol/L). Serum retinol and liver VA δ13C were significantly correlated (R2 = 0.92; P < 0.0001). Serum retinol δ13C differentiated control groups that consumed white maize and white carrots (−27.1 ± 1.2 δ13C‰) from treated groups that consumed orange maize and white carrots (−21.6 ± 1.4 δ13C‰ P < 0.0001) and white maize and orange carrots (−30.6 ± 0.7 δ13C‰ P < 0.0001). A prediction model demonstrated the relative contribution of orange maize to total dietary VA for groups that consumed VA from mixed sources. Conclusions: Provitamin A efficacy and quantitative estimation of the relative contribution to dietary VA were demonstrated with the use of serum retinol δ13C. This method could be used for maize efficacy or effectiveness studies and with

  9. DISTRIBUTION OF CATECHOLAMINERGIC AND PEPTIDERGIC CELLS IN THE GERBIL MEDIAL AMYGADALA, CAUDAL PREOPTIC AREA AND CAUDAL BED NUCLEI OF THE STRIA TERMINALIS WITH A FOCUS ON AREAS ACTIVATED AT EJACULATION

    PubMed Central

    Simmons, Danielle A.; Yahr, Pauline

    2010-01-01

    The posterodorsal preoptic nucleus (PdPN), lateral part of the posterodorsal medial amygdala (MeApd) and medial part of the medial preoptic nucleus (MPNm) are activated at ejaculation in male gerbils as assessed by Fos expression. We sought to immunocytochemically visualize substance P (SP), cholecystokinin (CCK), oxytocin, vasopressin and tyrosine hydroxylase (TH), a catecholaminergic marker, in the mating-activated cells, but the need for colchicine precluded behavioral testing. Instead, we detailed distributions of cells containing these molecules in the medial amygdala, caudal preoptic area and caudal bed nuclei of the stria terminalis (BST) and quantified their densities in the PdPN, MPNm and lateral MeApd for comparison to densities previously assessed for mating-activated efferents from these sites. TH cells were as dense in the PdPN and lateral MeApd as activated efferents to the anteroventral periventricular nucleus. In the lateral MeApd, TH cells were grouped where cells activated at ejaculation are clustered and where CCK cells form a ball. Lateral MeApd CCK cells and PdPN SP cells were as dense as activated efferents to the principal BST. Oxytocinergic PdPN cells and SP cells in the MPNm were as dense as mating-activated efferents to the lateral MeApd. If some oxytocin cells in the PdPN project to the neurohypophysis, as in rats, they could be a source of the oxytocin secreted at ejaculation. Since gerbils are monogamous and biparental, it was also interesting that, unlike monogamous prairie voles, they had few TH cells in the MeApd or dorsal BST, resembling promiscuous rats, hamsters and meadow voles. PMID:21087661

  10. Distribution of catecholaminergic and peptidergic cells in the gerbil medial amygdala, caudal preoptic area and caudal bed nuclei of the stria terminalis with a focus on areas activated at ejaculation.

    PubMed

    Simmons, Danielle A; Yahr, Pauline

    2011-01-01

    The posterodorsal preoptic nucleus (PdPN), lateral part of the posterodorsal medial amygdala (MeApd) and medial part of the medial preoptic nucleus (MPNm) are activated at ejaculation in male gerbils as assessed by Fos expression. We sought to immunocytochemically visualize substance P (SP), cholecystokinin (CCK), oxytocin, vasopressin and tyrosine hydroxylase (TH), a catecholaminergic marker, in the mating-activated cells, but the need for colchicine precluded behavioral testing. Instead, we detailed distributions of cells containing these molecules in the medial amygdala, caudal preoptic area and caudal bed nuclei of the stria terminalis (BST) and quantified their densities in the PdPN, MPNm and lateral MeApd for comparison to densities previously assessed for mating-activated efferents from these sites. TH cells were as dense in the PdPN and lateral MeApd as activated efferents to the anteroventral periventricular nucleus. In the lateral MeApd, TH cells were grouped where cells activated at ejaculation are clustered and where CCK cells form a ball. Lateral MeApd CCK cells and PdPN SP cells were as dense as activated efferents to the principal BST. Oxytocinergic PdPN cells and SP cells in the MPNm were as dense as mating-activated efferents to the lateral MeApd. If some oxytocin cells in the PdPN project to the neurohypophysis, as in rats, they could be a source of the oxytocin secreted at ejaculation. Since gerbils are monogamous and biparental, it was also interesting that, unlike monogamous prairie voles, they had few TH cells in the MeApd or dorsal BST, resembling promiscuous rats, hamsters and meadow voles. PMID:21087661

  11. Comparison of f2/f1 ratio functions in rabbit and gerbil: Ear-canal DPOAEs vs noninvasively inferred intracochlear DPs

    NASA Astrophysics Data System (ADS)

    Martin, Glen K.; Stagner, Barden B.; Dong, Wei; Lonsbury-Martin, Brenda L.

    2015-12-01

    The properties of distortion product otoacoustic emissions (DPOAEs), i.e., distortion products (DPs) measured in the ear canal, have been thoroughly described. However, considerably less is known about the behavior of intracochlear DPs (iDPs). Detailed comparisons of DPOAEs to iDPs would provide valuable insights on the extent to which ear-canal DPOAEs mirror iDPs. Prior studies described a technique whereby the behavior of iDPs could be inferred by interacting a probe tone (f3) with the iDP of interest to produce a `secondary' DPOAE (DPOAÉ). The behavior of DPOAÉ was then used to deduce the characteristics of the iDP. In the present study, this method was used in rabbits and gerbils to simultaneously compare DPOAE f2/f1-ratio functions to their iDP counterparts. The 2f1-f2 and 2f2-f1 DPOAEs were collected with f1 and f2 primary-tone levels varied from 35-75 dB SPL, and with a 50-dB SPL f3 placed at a DP/f3 ratio of 1.25 to evoke a DPOAÉ at 2f3-(2f1-f2) or 2f3-(2f2-f1). Control experiments demonstrated little effect of the f3-probe tone on DPOAE-ratio functions. Substitution experiments were performed to determine any suppressive effects of the f1 and f2 primaries on the generation of DPOAÉ, as well as to infer the intracochlear level of the iDP once the DPOAÉ was corrected for suppression. Results showed that at low primary-tone levels, 2f1-f2 DPOAE f2/f1-ratio functions peaked around f2/f1=1.25, and exhibited an inverted U-shaped function. In contrast, simultaneously measured 2f1-f2 iDP-ratio functions peaked at f2/f1≈1. Similar growth of the inferred iDP was obtained for higher-level primaries when the ratio functions were corrected for suppressive effects. At these higher levels, DPOAE-ratio functions leveled off and no longer showed the steep reduction at narrow f2/f1 ratios. Overall, noninvasive estimates of 2f1-f2 iDP-ratio functions agreed with reports of similar functions directly measured for 2f1-f2 DPs on the basilar membrane (BM) or in

  12. Books by the Gerbil Cage.

    ERIC Educational Resources Information Center

    Diffily, Deborah; Fox, Jill Englebright

    1999-01-01

    Presents suggestions for incorporating reading and writing in several early childhood classroom learning centers. Includes tips for basic materials and activities for reading, writing, music or listening, housekeeping, science, blocks, and art centers. Also includes suggested children's books. (KB)

  13. Micromechanics in the Gerbil Hemicochlea

    NASA Astrophysics Data System (ADS)

    Richter, C.-P.; Dallos, P.

    2003-02-01

    Micromechanical events in the cochlea represent the combined motions of all elements that convey vibrations from the basilar membrane (BM) to the stereocilia bundles of the inner hair cells, the sensory receptors of the mammalian cochlea. Because of the difficulty of visualizing the organ of Corti (OC), experimental data on micromechanics are extremely limited. Available results represent motions viewed either from one focal plane or from the surface of a cochlear preparation. The present experiments examine cochlear micromechanics at audio frequencies by using the hemicochlea that permits the viewing of all structures in a cochlear cross-section. Stroboscopic illumination and video-flow techniques have been used to quantify the motion of selected elements. The movements at different locations revealed a tuned response across frequencies with the best frequency increasing from more basal to more apical locations. Furthermore, the vibrations showed rotational components, such as rotations around a pivot point: the inner pillar foot. Inner and outer pillar cells, inner and outer hair cells, Deiters' cells and parts of the BM move together and form a so-called "rotating wedge". The movements of Hensen's cells represent a mode of vibration different from that of the rest of the OC.

  14. A Genetically-Encoded YFP Sensor with Enhanced Chloride Sensitivity, Photostability and Reduced pH Interference Demonstrates Augmented Transmembrane Chloride Movement by Gerbil Prestin (SLC26a5)

    PubMed Central

    Zhong, Sheng; Navaratnam, Dhasakumar; Santos-Sacchi, Joseph

    2014-01-01

    Background Chloride is the major anion in cells, with many diseases arising from disordered Cl− regulation. For the non-invasive investigation of Cl− flux, YFP-H148Q and its derivatives chameleon and Cl-Sensor previously were introduced as genetically encoded chloride indicators. Neither the Cl− sensitivity nor the pH-susceptibility of these modifications to YFP is optimal for precise measurements of Cl− under physiological conditions. Furthermore, the relatively poor photostability of YFP derivatives hinders their application for dynamic and quantitative Cl− measurements. Dynamic and accurate measurement of physiological concentrations of chloride would significantly affect our ability to study effects of chloride on cellular events. Methodology/Principal Findings In this study, we developed a series of YFP derivatives to remove pH interference, increase photostability and enhance chloride sensitivity. The final product, EYFP-F46L/Q69K/H148Q/I152L/V163S/S175G/S205V/A206K (monomeric Cl-YFP), has a chloride Kd of 14 mM and pKa of 5.9. The bleach time constant of 175 seconds is over 15-fold greater than wild-type EYFP. We have used the sensor fused to the transmembrane protein prestin (gerbil prestin, SLC26a5), and shown for the first time physiological (mM) chloride flux in HEK cells expressing this protein. This modified fluorescent protein will facilitate investigations of dynamics of chloride ions and their mediation of cell function. Conclusions Modifications to YFP (EYFP-F46L/Q69K/H148Q/I152L/V163S/S175G/S205V/A206K (monomeric Cl-YFP) results in a photostable fluorescent protein that allows measurement of physiological changes in chloride concentration while remaining minimally affected by changes in pH. PMID:24901231

  15. Therapeutic efficacy of the multi-epitope vaccine CTB-UE against Helicobacter pylori infection in a Mongolian gerbil model and its microRNA-155-associated immuno-protective mechanism.

    PubMed

    Lv, Xiaobo; Yang, Jue; Song, Hui; Li, Tong; Guo, Le; Xing, Yingying; Xi, Tao

    2014-09-15

    Vaccination is an effective means of preventing infectious diseases, including those caused by Helicobacter pylori. In this study, we constructed a novel multi-epitope vaccine, CTB-UE, composed of the cholera toxin B subunit and tandem copies of the B and Th cell epitopes from the H. pylori urease A and B subunits. We evaluated the therapeutic efficacy of the multi-epitope vaccine CTB-UE against H. pylori infection in a Mongolian gerbil model and studied its immuno-protective mechanisms. The experimental results indicated that urease activity, H. pylori colonisation density, the levels of IL-8 and TNF-α in the serum, and the levels of COX-2 and NAP in gastric tissue were significantly lower and the IgG level in the serum and the IFN-γ level in spleen lymphocytes were significantly higher in the vaccinated group compared with the model control group; additionally, gastric mucosal inflammation was notably alleviated following vaccination. The results showed that CTB-UE had a good therapeutic effect on H. pylori infection. The immuno-protective mechanism was closely related to the immune response mediated by microRNA-155, the expression of which was strongly up-regulated after CTB-UE administration. The expression levels of the microRNA-155 target proteins IFN-γRα, AID, and PU.1 were significantly down-regulated; these results indicated that CTB-UE induced an immune response biased towards Th1 cells by up-regulating microRNA-155 to inhibit IFN-γRα expression and induced a humoral immune response towards B cells by up-regulating microRNA-155 to inhibit PU.1 and AID expression. These results demonstrate that the multi-epitope vaccine CTB-UE may be a promising therapeutic vaccine against H. pylori infection and is a new therapeutic tool for human use. PMID:25093281

  16. Ultrastructural characterization of gerbil olivocochlear neurons based on differential uptake of /sup 3/H-D-aspartic acid and a wheatgerm agglutinin-horseradish peroxidase conjugate from the cochlea

    SciTech Connect

    Helfert, R.H.; Schwartz, I.R.; Ryan, A.F.

    1988-09-01

    Two populations of olivocochlear (OC) neurons have been identified in the gerbil brain stem on the basis of differential labeling patterns of 3H-D-aspartic acid (D-ASP) and wheatgerm agglutinin-horseradish peroxidase conjugate (WGA/HRP) from the cochlear perilymph. While both populations are capable of uptake and retrograde uptake of WGA/HRP, one population accumulates and retrogradely transports D-ASP (D-ASP OC neurons) and the other does not (non-D-ASP OC neurons). D-ASP OC neurons are found in or near the lateral superior olive, are small in size, and receive very few synaptic contacts. The vast majority of these synapses contain small, mildly pleomorphic vesicles with scattered dense core vesicles. Synapses with distinctly larger pleomorphic vesicles have also been observed. These neurons possess all of the features common to neurons of the lateral olivocochlear system. Non-D-ASP OC neurons are found primarily in the ventral nucleus of the trapezoid body, as well as in the area between the medial superior olive and the medial nucleus of the trapezoid body. These neurons are larger and receive greater numbers and types of synaptic contacts than those found on D-ASP OC neurons. The 2 most common synapses found on non-D-ASP OC neurons are axosomatic ones containing small, mildly pleomorphic vesicles and scattered dense core vesicles similar to those seen on the D-ASP OC neurons, and axodendritic synapses containing large, round vesicles. Much less frequently observed are synapses containing small, round vesicles or ones containing predominantly flat vesicles. The ultrastructural features of the non-D-ASP OC neurons correspond to those described for neurons of the medial olivocochlear system.

  17. Evaluation of brodifacoum against T. indica, M. hurrianae and R. rattus.

    PubMed Central

    Mathur, R. P.; Prakash, I.

    1981-01-01

    Brodifacoum was evaluated in the laboratory against the two gerbils, Tatera indica and Meriones hurrianae and the house rat, Rattus rattus. The acute oral LD50 for these rodents was found to be 0.10 mg/kg, 0.083 mg/kg and 0.77 mg/kg respectively. Feeding tests with 0.002% and 0.005% brodifacoum produced a 100% mortality after a 3-day feeding period in the gerbils and after a 4-day period in R. rattus. The anticoagulant is toxic at both the concentrations to all three species but is less palatable in comparison to plain baits. Results of this laboratory evaluation indicates that 0.002% brodifacoum-treated bait can be effectively used against T. indica, M. hurrianae and R. rattus. PMID:7288172

  18. Haemonchus contortus: Applications in Drug Discovery.

    PubMed

    Geary, T G

    2016-01-01

    Haemonchus contortus is an important pathogen of small ruminants and is therefore a crucially important target for anthelmintic chemotherapy. Its large size and fecundity have been exploited for the development of in vitro screens for anthelmintic discovery that employ larval and adult stages in several formats. The ability of the parasite to develop to the young adult stage in Mongolian jirds (Meriones unguiculatus) provides a useful small animal model that can be used to screen compounds prior to their evaluation in infected sheep. This chapter summarizes the use of H. contortus for anthelmintic discovery, offers a perspective on current strategies in this area and suggests research challenges that could lead to improvements in the anthelmintic discovery process. PMID:27238010

  19. Immunocytochemical studies on several developmental stages of Dipetalonema viteae (Filarioidea).

    PubMed

    Prüsse, A; Vollmer, S; Diesfeld, H J

    1983-09-01

    The binding of antibodies to infective larvae (L3), eggs, uterine contents and blood microfilariae was demonstrated by light microscopy employing the peroxidase-antiperoxidase (PAP) method. Antigen-antibody reactions were located on the shell of filarial eggs as well as on the cuticle and the interior of L3 and microfilariae. Using sera from Meriones unguiculatus, Mastomys natalensis and golden hamsters infected with D. viteae obtained at 7, 14, 21 and 28 weeks p.i. it was observed that the intensity of the immunostaining on several developmental stages of the filariae decreased with increasing duration of infection. This effect was more pronounced in the case of M. unguiculatus and M. natalensis than in the case of golden hamsters. For detection of surface antigenicity the simple procedure of drying the test material on microscopic slides proved to be time saving and equally specific as compared to the embedding in Epon of the filarial stages and the successive preparation of semithin sections. However, embedded filarial stages presented more intensive immunostaining than nonembedded stages. Moreover, sections allowed to demonstrate antigen-antibody reactions on the cuticle as well as inside the body cavity of the stages. PMID:6685362

  20. PCR detection and sequencing of parasite ITS-rDNA gene from reservoirs host of zoonotic cutaneous leishmaniasis in central Iran.

    PubMed

    Parvizi, Parviz; Moradi, Ghasem; Akbari, Ghasem; Farahmand, Mahin; Ready, Paul D; Piazak, Norair; Assmar, Mehdi; Amirkhani, Aref

    2008-11-01

    Leishmania major is the causative agent of zoonotic cutaneous leishmaniasis (ZCL) in which gerbils are the reservoir host. ZCL is of great public health importance in Iran. In the current investigation, nested polymerase chain reaction (PCR) protocols were used to amplify a region of the ribosomal RNA amplicon of Leishmania (ITS1-5.8S rRNA gene). The PCR assays detected L. major in three rodent species: Rhombomis opimus, Meriones lybicus and, for first time, Meriones persicus. L. major parasite was found in Natanz, Isfahan Province in the center of Iran in a focus of rural zoonotic cutaneous leishmaniasis. Four L. major infections were detected in R. opimus species, three in M. Lybicus, and two in M. persicus. All nine rodent infections of L. major were found to be the same haplotype based on the PCR detection and sequencing of parasite ITS-ribosomal DNA gene. In addition, also for the first time, the nested PCR assays detected Leishmania tropica only in one M. persicus. Allied to studies in country, the new findings mean that past conclusions about the reservoir of L. major in Iran must be treated with caution. Finding two Leishmania species in different rodent species as reservoir in Iran, therefore, careful molecular eco-epidemiological investigations will be an essential part of modeling the roles of different gerbil species in maintaining and spreading ZCL foci. PMID:18791741

  1. Structure and function of the mammalian middle ear. I: Large middle ears in small desert mammals.

    PubMed

    Mason, Matthew J

    2016-02-01

    Many species of small desert mammals are known to have expanded auditory bullae. The ears of gerbils and heteromyids have been well described, but much less is known about the middle ear anatomy of other desert mammals. In this study, the middle ears of three gerbils (Meriones, Desmodillus and Gerbillurus), two jerboas (Jaculus) and two sengis (elephant-shrews: Macroscelides and Elephantulus) were examined and compared, using micro-computed tomography and light microscopy. Middle ear cavity expansion has occurred in members of all three groups, apparently in association with an essentially 'freely mobile' ossicular morphology and the development of bony tubes for the middle ear arteries. Cavity expansion can occur in different ways, resulting in different subcavity patterns even between different species of gerbils. Having enlarged middle ear cavities aids low-frequency audition, and several adaptive advantages of low-frequency hearing to small desert mammals have been proposed. However, while Macroscelides was found here to have middle ear cavities so large that together they exceed brain volume, the bullae of Elephantulus are considerably smaller. Why middle ear cavities are enlarged in some desert species but not others remains unclear, but it may relate to microhabitat. PMID:26104342

  2. Characterization of auditory synaptic inputs to gerbil perirhinal cortex.

    PubMed

    Kotak, Vibhakar C; Mowery, Todd M; Sanes, Dan H

    2015-01-01

    The representation of acoustic cues involves regions downstream from the auditory cortex (ACx). One such area, the perirhinal cortex (PRh), processes sensory signals containing mnemonic information. Therefore, our goal was to assess whether PRh receives auditory inputs from the auditory thalamus (MG) and ACx in an auditory thalamocortical brain slice preparation and characterize these afferent-driven synaptic properties. When the MG or ACx was electrically stimulated, synaptic responses were recorded from the PRh neurons. Blockade of type A gamma-aminobutyric acid (GABA-A) receptors dramatically increased the amplitude of evoked excitatory potentials. Stimulation of the MG or ACx also evoked calcium transients in most PRh neurons. Separately, when fluoro ruby was injected in ACx in vivo, anterogradely labeled axons and terminals were observed in the PRh. Collectively, these data show that the PRh integrates auditory information from the MG and ACx and that auditory driven inhibition dominates the postsynaptic responses in a non-sensory cortical region downstream from the ACx. PMID:26321918

  3. Generation of Distortion Product Otoacoustic Emissions in the Gerbil Cochlea

    NASA Astrophysics Data System (ADS)

    Dong, Wei; Olson, Elizabeth S.

    2011-11-01

    Simultaneous measurements of intracochlear and ear canal pressure responses to two-tone stimulation with fixed f2/f1 ratio allowed us to probe the physical generation sites of distortion product otoacoustic emissions (DPOAEs) in the cochlea. Our results were consistent with the notion that DPOAE emerges primarily from the generator region, where the two primaries overlap.

  4. Differential Measurement of Basilar Membrane Vibration in Sensitive Gerbil Cochleae

    NASA Astrophysics Data System (ADS)

    Ren, Tianying; He, Wenxuan

    2009-02-01

    Basilar membrane vibrations in the transverse direction were measured at two longitudinal locations using a laser interferometer. The magnitude transfer function of the cochlear partition between the two locations was obtained by calculating the ratio of the vibration magnitude at the apical location to that at the basal location as a function of the stimulus frequencies. Measured differential transfer function showed a response peak at a frequency below the best frequency of the apical location with a magnitude >1, and the minimum magnitude near the best frequency of the basal location with an amplitude as small as 0.01. These data indicate that the cochlea achieves its high sensitivity, sharp tuning, and nonlinearity through amplification and attenuation of basilar membrane vibration.

  5. A SCIENCE PROGRAM FOR THE ELEMENTARY SCHOOLS OF LOWER MERION SCHOOL DISTRICT.

    ERIC Educational Resources Information Center

    Lower Merion Township School District, Ardmore, PA.

    AFTER AN EVALUATION MADE BY THE TEACHERS OF KINDERGARTEN THROUGH GRADE 6, THE FOLLOWING AREAS OF CLARIFICATION, REWRITING, OR ADDITIONS WERE INDICATED--THE PURPOSE AND USE OF THE SCIENCE GUIDE, EVALUATION OF THE UNITS BY GRADES, ADDITIONAL MATERIALS FOR THE UNITS, A REWRITING OF PARTICULAR UNITS, HEALTH UNITS FOR GRADES 1 THROUGH 5, THE USE OF…

  6. Safety evaluation of the SAG2 rabies virus mutant in Tunisian dogs and several non-target species.

    PubMed

    Hammami, S; Schumacher, C L; Cliquet, F; Barrat, J; Tlatli, A; Ben Osman, R; Aouina, T; Aubert, A; Aubert, M

    1999-01-01

    The safety of the SAG2 rabies virus, a highly attenuated mutant of the SAD strain intended to vaccinate dogs by the oral route, was evaluated in local Tunisian dogs and in five other local species likely to consume vaccine baits. These species were the domestic cat (Felis catus), the jackal (Canis aureus), the jerboa (Jaculus orientalis), the merion (Meriones sp.) and the gerbil (Gerbillus campestris). The vaccine was administered orally to 21 dogs, 11 cats and eight jackals and orally or intramuscularly to 62 wild rodents of the above-mentioned species. Seven dogs, one cat, five jackals all juvenile and with poor health status) and two rodents died for intercurrent causes. The others were observed for 60-180 days. No animal showed any rabies symptom. Seroneutralizing antibodies were observed in all experimental groups, only after vaccination, with the highest rate being observed in jackals and rodents. The rabies virus was detected in the oral cavity of three cats 6 h after oral instillation, but was not isolated later either in saliva or in salivary glands. Tissue samples (brain and salivary glands) from dead or euthanized animals were examined for the rabies virus antigen by a fluorescent antibody test. No rabies antigen was detected. These trials confirm the safety of the SAG2 strain on the Tunisian species already demonstrated by other authors on many other target and non target species. PMID:10478416

  7. In Vitro Activities of Benzimidazoles against Echinococcus multilocularis Metacestodes

    PubMed Central

    Jura, Heike; Bader, Augustinus; Frosch, Matthias

    1998-01-01

    Alveolar echinococcosis, caused by the larval (metacestode) stage of the tapeworm Echinococcus multilocularis, is a lethal parasitosis of the liver prevalent in the Northern Hemisphere. For chemotherapy the benzimidazole derivatives mebendazole and albendazole were introduced, and their use has resulted in a significant improvement in the survival rates. However, data from experiments with animals and clinical observations indicate that these drugs elicit only parasitostatic activity and in most cases are not able to completely eliminate the parasitic metacestode tissue. In the present study, we applied a culture system for the in vitro growth and proliferation of E. multilocularis metacestodes to analyze the parasitostatic and parasitocidal potential of mebendazole. Here, we demonstrate for the first time that at concentrations of >0.1 μM, i.e., at concentrations used for therapy of human alveolar echinococcosis, this antihelminth drug is parasitocidal in vitro. Viability assessment was performed by infection experiments with Meriones unguiculatus and mebendazole-treated metacestode tissue and by reverse transcription-PCR for the detection of E. multilocularis mRNA. The E. multilocularis in vitro model proved to be a valuable tool for the analysis of the potential of antihelminth drugs. PMID:9593125

  8. Ca2+ current - driven nonlinear amplification by the mammalian cochlea in vitro

    PubMed Central

    Chan, Dylan K.; Hudspeth, A. J.

    2007-01-01

    An active process in the inner ear expends energy to enhance the sensitivity and frequency selectivity of hearing. Two mechanisms have been proposed to underlie this process in the mammalian cochlea: receptor-potential-based electromotility and Ca2+-driven active hair-bundle motility. To link the phenomenology of the cochlear amplifier with these cellular mechanisms, we developed an in vitro cochlear preparation from Meriones unguiculatus that affords optical access to the sensory epithelium while mimicking its in vivo environment. Acoustic and electrical stimulation elicited microphonic potentials and electrically evoked hair-bundle movement, demonstrating intact forward and reverse mechanotransduction. The mechanical responses of hair bundles from inner hair cells revealed a characteristic resonance and a compressive nonlinearity diagnostic of the active process. Blocking transduction with amiloride abolished nonlinear amplification, whereas eliminating all but the Ca2+ component of the transduction current did not. The results suggest that the Ca2+ current drives the cochlear active process and support the hypothesis that active hair-bundle motility underlies cochlear amplification. PMID:15643426

  9. Larva migrans by Baylisascaris transfuga: fatal neurological diseases in Mongolian jirds, but not in mice.

    PubMed

    Sato, Hiroshi; Matsuo, Kayoko; Osanai, Arihiro; Kamiya, Haruo; Akao, Nobuaki; Owaki, Shigeo; Furuoka, Hidefumi

    2004-08-01

    Raccoon roundworms (Baylisascaris procyonis) and other Baylisascaris species cause patent or latent larva migrans (LM) in a variety of mammals and birds, including humans. It is not clear whether LM by Baylisascaris transfuga, roundworms of bears, is associated with clinical neurological disorders. To clarify this issue, ICR and BALB/c mice as well as Mongolian jirds (Meriones unguiculatus) were orally inoculated with 2,000-5,000 embryonated eggs of B. transfuga. In mice, the ascarid caused symptomatic LM of limited extent and duration, whereas the infection was fatal in jirds; i.e., they exhibited general signs such as severe depression and emaciation on days 8-11 postinfection (PI) and died, or they developed progressive and fatal neurological disorders after day 14 PI. Histological examination showed B. transfuga larvae in the brain of all mice and jirds examined, and the larvae collected from them developed to a size comparable with that of B. procyonis. There existed, however, critical differences in host reactions against larvae localized in the brain of mice and jirds; B. transfuga larvae found in mice were surrounded by granulomatous reactions and immobilized, whereas larvae found in jirds were free from any host reaction and mobile, causing extensive malacia. PMID:15357068

  10. Ecological Niche Modeling of main reservoir hosts of zoonotic cutaneous leishmaniasis in Iran.

    PubMed

    Gholamrezaei, Mostafa; Mohebali, Mehdi; Hanafi-Bojd, Ahmad Ali; Sedaghat, Mohammad Mehdi; Shirzadi, Mohammad Reza

    2016-08-01

    Zoonotic cutaneous leishmaniasis (ZCL), caused by Leishmania major, is a common zoonotic vector-borne disease in Iran. Close contact with infected reservoir hosts increases the probability of transmission of Leishmania parasite infections to susceptible humans. Four gerbil species (Rodentia: Gerbillidae) serve as the main reservoir hosts for ZCL in different endemic foci of Iran. These species include Rhombomys opimus, Meriones libycus, Meriones hurrianae and Tatera indica; while notable infection has been reported in Nesokia indica as well. The purpose of this study is to model the distribution of these reservoirs to identify the risk areas of ZCL. A data bank was developed including all published data during the period of 1970-2015. Maximum entropy model was used to find the most appropriate ecological niches for each species. The areas under curve obtained were 0.961, 0.927, 0.922, 0.997 and 0.899, instead of 1, for training test in R. opimus, M. libycus, T. indica, M. hurrianae and N. indica, respectively. The environmental variable with the highest gain when used in isolation was slope for R. opimus and N. indica, annual mean temperature for M. libycus, and seasonal precipitation for T. indica and M. hurrianae. Summation of presence probabilities for three main species, i.e., R. opimus, M. libycus and T. indica revealed favorable ecological niches in wide areas of 16 provinces. This is the first study to predict the distribution of ZCL reservoir hosts in Iran. Climatology and topography variables had high contributions toward the prediction of potential distribution of the main reservoir species; therefore, as climate changes, the models should be updated periodically with novel data, and the results should be used in disease-monitoring programs. PMID:27150212

  11. A computational study on traveling waves in the gerbil cochlea generated by electrical impulse

    NASA Astrophysics Data System (ADS)

    Nam, Jong-Hoon; Liu, Yanju; Gracewski, Sheryle M.

    2015-12-01

    Through model simulations, we investigated the cochlear traveling waves formed by outer hair cell (OHC) motility. Two sets of governing equations, one representing the solid domain of the organ of Corti complex (OCC) and the other representing the fluid domain, were solved simultaneously in the time domain. The OHCs incorporated electro-mechanical motility driven by prestin molecules. The combined fluid-solid interaction model was verified by simulating passive traveling waves along the cochlear coil. When stimulated with an electrical impulse, the OCC formed traveling waves propagating toward the apex. Without the Y-shaped structures in the OCC formed by the OHCs and the Deiter's cell processes, the active OHCs form dispersive waves rather than traveling waves upon electrical stimulation.

  12. Acanthocheilonema viteae: Vaccination of jirds with irradiation-attenuated stage-3 larvae and with exported larval antigens

    SciTech Connect

    Lucius, R.; Textor, G.; Kern, A.; Kirsten, C. )

    1991-08-01

    Jirds (Meriones unguiculatus) were immunized with irradiated (35 krad) stage-3 larvae (L3) of Acanthocheilonema viteae. The induced resistance against homologous challenge infection and the antibody response of the animals were studied. Immunization with 3, 2, or 1 dose of 50 irradiated L3 induced approximately 90% resistance. Immunization with a single dose of only 5 irradiated L3 resulted in 60.8% protection while immunization with a single dose of 25 L3 induced 94.1% protection. The protection induced with 3 doses of 50 irradiated L3 did not decrease significantly during a period of 6 months. Sera of a proportion, but not all resistant jirds, contained antibodies against the surface of vector derived L3 as defined by IFAT. No surface antigens of microfilariae or adult worms were recognized by the sera. Vaccinated animals had antibody responses against antigens in the inner organs of L3 and in the cuticle and reproductive organs of adult worms as shown by IFAT. Immunoblotting with SDS-PAGE-separated L3 antigens and L3-CSN revealed that all sera contained antibodies against two exported antigens of 205 and 68 kDa, and against a nonexported antigen of 18 kDa. The 205-kDa antigen easily degraded into fragments of 165, 140, 125, and 105 kDa which were recognized by resistant jird sera. Various antigens of adult worms, but relatively few antigens of microfilariae, were also recognized. To test the relevance of exported antigens of L3 to resistance, jirds were immunized with L3-CSN together with a mild adjuvant. This immunization induced 67.7% resistance against challenge infection and sera of the immunized animals recognized the 205- and 68-kDa antigens of L3.

  13. Moxidectin causes adult worm mortality of human lymphatic filarial parasite Brugia malayi in rodent models.

    PubMed

    Verma, Meenakshi; Pathak, Manisha; Shahab, Mohd; Singh, Kavita; Mitra, Kalyan; Misra-Bhattacharya, Shailja

    2014-12-01

    Moxidectin is a macrocyclic lactone belonging to milbemycin family closely related to ivermectin and is currently progressing towards Phase III clinical trial against human infection with the filaria Onchocerca volvulus (Leuckart, 1894). There is a single report on the microfilaricidal and embryostatic activity of moxidectin in case of the human lymphatic filarial parasite Brugia malayi (Brug, 1927) in Mastomys coucha (Smith) but without any adulticidal action. In the present study, the in vitro and in vivo antifilarial efficacy of moxidectin was evaluated on, B. malayi. In vitro moxidectin showed 100% reduction in adult female worm motility at 0.6 μM concentration within 7 days with 68% inhibition in the reduction of MTT (3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide dye) (which is used to detect viability of worms). A 50% inhibitory concentration (IC50) of moxidectin for adult female parasite was 0.242 μM, for male worm 0.186 μM and for microfilaria IC50 was 0.813 μM. In adult B. malayi-transplanted primary screening model (Meriones unguiculatus Milne-Edwards), moxidectin at a single optimal dose of 20 mg/kg by oral and subcutaneous route was found effective on both adult parasites and microfilariae. In secondary screening (M coucha, subcutaneously inoculated with infective larvae), moxidectin at the same dose by subcutaneous route brought about death of 49% of adult worms besides causing sterilisation in 54% of the recovered live female worms. The treated animals exhibited a continuous and sustained reduction in peripheral blood microfilaraemia throughout the observation period of 90 days. The mechanism of action of moxidectin is suggested to be similar to avermectins. The in silico studies were also designed to explore the interaction of moxidectin with glutamate-gated chloride channels of B. malayi. The docking results revealed a close interaction of moxidectin with various GluCl ligand sites of B. malayi. PMID:25651699

  14. Development of culture-based serological assays to diagnose Babesia divergens infections.

    PubMed

    Gabrielli, Simona; Galuppi, Roberta; Marcer, Federica; Marini, Carla; Tampieri, Maria Paola; Moretti, Annabella; Pietrobelli, Mario; Cancrini, Gabriella

    2012-02-01

    Babesioses are hematic tick-borne diseases that induce malaria-like disorders in domestic, wild animals, and humans. Although indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) commercial kits are available to test the presence of antibodies against most Babesia species, no kit exists to serologically diagnose the infections due to Babesia divergens, one of the most important zoonotic species. To fill this gap and to develop assays to detect animal and human infections, in vitro cultures (microaerophilous stationary phase system) of B. divergens were organized. Infected erythrocytes were adsorbed as corpuscular antigen (CA) on IFAT slides and ELISA microwells. The supernatant medium of the cultures (metabolic antigen, MA) was collected and employed in ELISA and western blot (WB) assays. B. divergens was also used to produce positive sera in Meriones unguiculatus and to infect a calf. Serological tests were set up with sera from experimentally/naturally infected animals, and possible cross-reactions were evaluated using heterologous sera from cattle positive to other piroplasms. Sera from clinically healthy people at risk of infection were also tested. As expected, assays based on the purified MAs from in vitro cultures proved more sensitive and specific than CA-IFAT and CA-ELISA. In fact, MA-ELISA provided satisfactory performances (even if 8.4%-15.7% cross-reactions were evidenced), and the WB developed proved totally sensitive and specific. WB indicated as immunodominant antigens two major protein bands at 33 and 37 kDa, which were also evidenced in 2.2% of the human sera tested, proving the parasite transmission to humans also in Italy. PMID:21995263

  15. Coevolution of Cryptosporidium tyzzeri and the house mouse (Mus musculus)✯

    PubMed Central

    Kváč, Martin; McEvoy, John; Loudová, Martina; Stenger, Brianna; Sak, Bohumil; Květoňová, Dana; Ditrich, Oleg; Rašková, Veronika; Moriarty, Elaine; Rost, Michael; Macholán, Miloš; Piálek, Jaroslav

    2013-01-01

    Two house mouse subspecies occur in Europe, eastern and northern Mus musculus musculus (Mmm) and western and southern Mus musculus domesticus (Mmd). A secondary hybrid zone occurs where their ranges meet, running from Scandinavia to the Black Sea. In this paper, we tested a hypothesis that the apicomplexan protozoan species Cryptosporidium tyzzeri has coevolved with the house mouse. More specifically, we assessed to what extent the evolution of this parasite mirrors divergence of the two subspecies. In order to test this hypothesis, we analyzed sequence variation at five genes (ssrRNA, Cryptosporidium oocyst wall protein (COWP), thrombospondin-related adhesive protein of Cryptosporidium 1 (TRAP-C1), actin and gp60) in C. tyzzeri isolates from Mmd and Mmm sampled along a transect across the hybrid zone from the Czech Republic to Germany. Mmd samples were supplemented with mice from New Zealand. We found two distinct isolates of C. tyzzeri, each occurring exclusively in one of the mouse subspecies (C. tyzzeri-Mmm and C. tyzzeri-Mmd). In addition to genetic differentiation, oocysts of the C. tyzzeri-Mmd subtype (mean: 4.24 × 3.69 μm) were significantly smaller than oocysts of C. tyzzeri-Mmm (mean: 4.49 × 3.90 μm). Mmm and Mmd were susceptible to experimental infection with both C. tyzzeri subtypes; however, the subtypes were not infective for the rodent species Meriones unguiculatus, Mastomys coucha, Apodemus flavicollis or Cavia porcellus. Overall, our results support the hypothesis that C. tyzzeri is coevolving with Mmm and Mmd. PMID:23791796

  16. Infectivity of Swiss Giardia isolates to jirds and mice, and in vitro cultivation of trophozoites originating from sheep.

    PubMed

    Gasser, R B; Eckert, J; Rohrer, L

    1987-01-01

    The susceptibility of Giardia-free jirds (Meriones unguiculatus) and AJ-strain mice to oral inoculation with cysts from Swiss Giardia isolates was assessed. Giardia cysts of human, dog, cat, and sheep origin produced infections in jirds (4-10 weeks old). AJ-strain mice (6 weeks old) were insusceptible to Giardia from man, dog, and cat. The number of Giardia cysts inoculated per rodent ranged from 5000 to 12,600. The course of infection was studied in jirds experimentally infected with a Giardia isolate of cat origin. After administration of 6300 cysts to each of 16 jirds, 5 (31%) started to excrete cysts 4-5 days post inoculation (p.i.). Cyst excretion patterns were mostly intermittent, patency periods lasted 5-28 days, and average cyst numbers per g feces of individual jirds varied between 118,500 and 835,200 (maximal number: 3216700). The parasites were eliminated spontaneously in all 5 jirds. The Giardia isolate of cat origin was passaged 4 times in the jird. A Giardia isolate obtained from sheep was transferred in the cyst stage to jirds. Giardia trophozoites isolated from one of these jirds have been axenically cultivated in vitro in a modified, filter-sterilized TYI-S-33 culture medium and successfully cryopreserved. To our knowledge, this is the first report on axenic cultivation of Giardia of sheep origin. Giardia from cats could not be cultivated in vitro under the same conditions. The fact that Swiss Giardia isolates from humans and various domestic animals are not strictly host-specific is in agreement with similar findings from other areas and suggests a zoonotic character for giardiasis.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2964036

  17. [Taxonomic status of the Artashat virus (ARTSV) (Bunyaviridae, Nairovirus) isolated from the ticks Ornithodoros alactagalis Issaakjan, 1936 and O. verrucosus Olenev, Sassuchin et Fenuk, 1934 (Argasidae Koch, 1844) collected in Transcaucasia].

    PubMed

    Al'khovskiĭ, S V; L'vov, D K; Shchelkanov, M Iu; Shchetinin, A M; Deriabin, P G; Gitel'man, A K; Botikov, A G; Samokhvalov, E I; Zakarian, V A

    2014-01-01

    The Artashat virus (ARTSV) was originally isolated fom the Ornithodoros alactagalis Issaakjan, 1936 (Argasidae Koch, 1844), which were collected in the burrow of small five-toed jerboa (Allactaga elater Lichtenstein, 1825) in Armenia in 1972. Later, the ARTSV was isolated from the O. verrucosus Olenev, Sassuchin et Fenuk, 1934 collected in the burrows of Persian gerbil (Meriones persicus Blanford, 1875) in Azerbaijan. Based on the virion morphology, the ARTSV was assigned to the Bunyaviridae viruses. In this work, the ARTSV genome was partially sequenced (GenBank ID: KF801650) and it was shown that the ARTSV is a new member of the Nairovirus genus. ARTSV has from 42% (Issyk-Kul virus) to 58% (Raza virus, Hughes group) similarity with the nairoviruses for nucleotide sequence of part of RNA-dependent RNA-polymerase (RdRp). The similarity on the amino acid level is 65-70%. Low level of homology and the equidistant position of the ARTSV on phylogenetic tree indicate that the ARTSV is a new prototype species of the Nairovirus genus (Bunyaviridae) forming a separate phylogenetic branch. PMID:25335415

  18. First-year movements by juvenile Mexican spotted owls in the Canyonlands of Utah

    USGS Publications Warehouse

    Willey, D.W.; van Riper, Charles, III

    2000-01-01

    We studied first-year movements of Mexican Spotted Owls (Strix occidentalis lucida) during natal dispersal in canyonlands of southern Utah. Thirty-one juvenile Mexican Spotted Owls were captured and radiotracked during 1992-95 to examine behavior and conduct experiments related to the onset of natal dispersal. Juvenile Spotted Owls dispersed from their nest areas during September to October each year, with 85% leaving in September. The onset of movements was sudden and juveniles dispersed in varied directions. The median distance from nest area to last observed location was 25.7 km (range = 1.7-92.3 km). Three of 26 juveniles tracked (11%) were alive after one year, although none were observed with mates. We conducted a feeding experiment, using Mongolian gerbils (Meriones unguicuculatus), to test the influence of increased food supply on dispersal onset. The mean dispersal date of five owls that received supplemental food (Julian day no. 255 ?? 2.6 SD) was significantly different than a control group (day no. 273 ?? 12.3).

  19. On-host control of the brown dog tick Rhipicephalus sanguineus Latreille (Acari: Ixodidae) by Metarhizium brunneum (Hypocreales: Clavicipitaceae).

    PubMed

    Rot, A; Gindin, G; Ment, D; Mishoutchenko, A; Glazer, I; Samish, M

    2013-03-31

    Ticks are obligatory blood-sucking arthropods. Their life cycle includes a relatively short period of feeding on a vertebrate host and a long off-host period spent in the upper layer of the soil. Entomopathogenic fungi are known to be highly effective tick pathogens and the on-host application of these fungi may be a promising economic approach for tick control. In this study, we evaluated the tick control provided by spraying Metarhizium brunneum onto the tick's vertebrate host, specifically gerbils (Meriones tristrami) and rabbits (Oryctolagus cuniculus). The efficacy of the fungal treatment was not limited to a direct effect on the mortality of feeding ticks, but continued during molting (off host) and, in the case of female ticks, the treatment reduced the production of eggs and their hatching rate. The direct control of the on-host stages was relatively low (from 19 to 38%); whereas the effects of the applied fungus on subsequent tick development reduced the yield of the following engorged stages up to 30-63%. Engorged females that dropped from rabbits sprayed with M. brunneum laid 21.5% fewer eggs than the control females. Moreover, these ticks transmitted conidia by contact to the eggs which they laid, resulting a 3-fold reduction in the rate of hatching relative to the control. Based on theoretical cumulative calculations, these results suggest that if the progeny of each unfed stage feed on fungus-sprayed hosts, there will be a 92% reduction in the tick population within one generation. Two spray formulations, one based on mineral oil and another based on a starch-sucrose mixture, significantly enhanced on-host tick control, in comparison with an unformulated conidial suspension. The reduction in the number of nymphs that fed on the treated host and later developed into unfed adults was 54.9% for unformulated conidia, 70.4% for the oil formulation and 86.4% for the starch-sucrose formulation. Increasing the environmental humidity around the gerbils while

  20. FINE STRUCTURAL STUDY ON EMERIA SP. INFECTING THE LIBYAN JIRDS (MERIONES LIBYCUS) IN SAUDI ARABIA: MEROGONY, MACROGAMETOGENESIS AND HOST-PARASITE RELATIONSHIP.

    PubMed

    Alanazi, Abdullah D; Alanazi, Ashraf E Said; El-Kabbany, Amira I

    2015-08-01

    Ultrastructural characteristics of merogony and the development of mature merozoits and macrogametogensis of Eimeria sp. infecting the Libyan jird were investigated. Mono and binucleated schizonts were detected. Developed merozoites showed all the apicomplexan architecture (Pellicle, conoid, rhoptries, micronemes ... etc). Transformation into macrogametes were studied. Early macrogamonts characterized by the loss of all apicomblexan characters and the appearance of wall-forming bodies were the first indication for macrogametogenesis. As development precepded, two types of wall forming bodies (I, II) were clearly detected. Cell organelles including amylopectin granules and lipid globules were greatly increased in mature macrogametes. Young oocyst (zygote) with double-layer oocyst wall were also detected. Host cell reaction due to infection included hypertrophy of the infected host cell, enlargement, deformation and displacement of the host cell nucleus. Swollen and degeneration of mitochondria, endoplasmic reticulum and cytoplasmic vacuolation of the host cell. All parasite stages were enclosed in parasitophorous vacuole limited by unit membrane. Extended damage effect appeared in some neighboring host cell indicating the secretion of some toxins by the parasite. PMID:26485841

  1. The Role of Compression and Traveling Wave Pressures in the Transmission of Sound Out of the Gerbil Cochlea

    NASA Astrophysics Data System (ADS)

    Dong, Wei; Olson, Elizabeth S.

    2009-02-01

    Cochlear emissions provide a noninvasive probe of cochlear mechanics, but their utility is hindered by incomplete understanding of their relationship to intracochlear activity. In particular, recent work has uncovered a question about the mode by which emissions travel out of the cochlea - whether they emerge via a "fast" compression pressure or a "slow" traveling-wave pressure. We further probed this question with simultaneous measurements of intracochlear distortion products (DPs) at two well-separated locations and DP oto-acoustic emissions (DPOAEs). In the broad frequency range of the local best frequency (BF), the DP responses demonstrate the now well-known forward-traveling-wave character. However, at frequencies substantially lower than the BF, comparisons of both DPOAEs to DPs and of DPs at two locations support a reverse-traveling-wave. Finally, a compression pressure DP was observed when stimulating at high levels (90 dB) with frequencies that were well above the BF. Therefore, the compression / reverse-traveling-wave question appears to be a quantitative question of the relative size of these different pressure modes. In previous and present results we find that the reverse-traveling-wave mode can be dominant both within the cochlea and in the production of DPOAEs.

  2. Gedunin and photogedunin of Xylocarpus granatum possess antifilarial activity against human lymphatic filarial parasite Brugia malayi in experimental rodent host.

    PubMed

    Misra, Sweta; Verma, Meenakshi; Mishra, Sunil Kumar; Srivastava, Shishir; Lakshmi, Vijai; Misra-Bhattacharya, Shailja

    2011-11-01

    The present study is aimed to evaluate antifilarial activity of Xylocarpus granatum (fruit from Andaman) against human lymphatic filarial parasite Brugia malayi in vivo. The in vitro antifilarial activity has already been reported earlier for this mangrove plant which has traditionally been used against several ailments. Aqueous ethanolic crude extract, four fractions (ethyl acetate fraction, n-butanol fraction, water-soluble fraction and water-insoluble fraction) and pure molecule/s of X. granatum (fruit) were tested in vitro on adult worms and microfilariae (mf) of B. malayi and the active samples were further evaluated in vivo in B. malayi (intraperitoneally) i.p. transplanted in the jird model (Meriones unguiculatus) and Mastomys coucha subcutaneously infected with infective larvae (L3). The crude aqueous ethanolic extract was active in vitro (IC50: adult = 15.46 μg/ml; mf = 13.17 μg/ml) and demonstrated 52.8% and 62.7% adulticidal and embryostatic effect on B. malayi, respectively, in Mastomys at a dose of 5 × 50 mg/kg by oral route. The antifilarial activity was primarily localized in the ethyl acetate-soluble fraction which revealed IC50 of 8.5 and 6.9 μg/ml in adult and mf, respectively. This fraction possessed moderate adulticidal and embryostatic action in vivo in Mastomys. Out of eight pure molecules isolated from the active fraction, two compounds gedunin (IC50 = 0.239 μg/ml, CC50 = 212.5 μg/ml, SI = 889.1) and photogedunin (IC50 = 0.213 μg/ml, CC50 = 262.3 μg/ml, SI = 1231.4) at 5 × 100 mg/kg by subcutaneous route revealed excellent adulticidal efficacy resulting in to the death of 80% and 70% transplanted adult B. malayi in the peritoneal cavity of jirds respectively in addition to noticeable microfilaricidalo action on the day of autopsy. The findings reveal that the extract from the fruit X. granatum contains promising in vitro and in vivo antifilarial activity against human lymphatic filarial parasite B. malayi which could be attributed to

  3. Noise Trauma Induced Neural Plasticity Throughout the Auditory System of Mongolian Gerbils: Differences between Tinnitus Developing and Non-Developing Animals.

    PubMed

    Tziridis, Konstantin; Ahlf, Sönke; Jeschke, Marcus; Happel, Max F K; Ohl, Frank W; Schulze, Holger

    2015-01-01

    In this study, we describe differences between neural plasticity in auditory cortex (AC) of animals that developed subjective tinnitus (group T) after noise-induced hearing loss (NIHL) compared to those that did not [group non-tinnitus (NT)]. To this end, our analysis focuses on the input activity of cortical neurons based on the temporal and spectral analysis of local field potential (LFP) recordings and an in-depth analysis of auditory brainstem responses (ABR) in the same animals. In response to NIHL in NT animals we find a significant general reduction in overall cortical activity and spectral power as well as changes in all ABR wave amplitudes as a function of loudness. In contrast, T-animals show no significant change in overall cortical activity as assessed by root mean square analysis of LFP amplitudes, but a specific increase in LFP spectral power and in the amplitude of ABR wave V reflecting activity in the inferior colliculus (IC). Based on these results, we put forward a refined model of tinnitus prevention after NIHL that acts via a top-down global (i.e., frequency-unspecific) inhibition reducing overall neuronal activity in AC and IC, thereby counteracting NIHL-induced bottom-up frequency-specific neuroplasticity suggested in current models of tinnitus development. PMID:25713557

  4. Quantification of the three-dimensional morphology of coincidence detector neurons in the medial superior olive of gerbils during late postnatal development.

    PubMed

    Rautenberg, Philipp L; Grothe, Benedikt; Felmy, Felix

    2009-11-20

    In the mammalian medial superior olive (MSO), neurons compute the azimuthal location of sound sources by temporally precise coincidence detection. It is assumed that the dendritic morphology of MSO neurons plays a crucial role in this computational process. However, few quantitative data about the morphology of these neuronal coincidence detectors are available, limiting theoretical approaches. Such a quantitative morphological description of neurons of the mammalian MSO would also allow a comparative analysis with its avian analog, the nucleus laminaris. We used single-cell electroporation, microscopic reconstruction, and compartmentalization to extract anatomical parameters of MSO neurons and quantitatively describe their morphology and development between postnatal day 9 and 36. We found that developmental refinement occurs until P27, generating morphologically compact, cylinder-like cells with axons originating from the soma. The complexity of higher order dendrites decreases between postnatal days 9 and 21. This decrease in dendritic complexity is judged from counting and analyzing the location of dendritic branches and determining the distribution of the surface area and total length of neurons. During this developmental period, the average length of terminal branches increases about twofold, indicating an elimination of predominantly small branches. The cell volume increases more than 1.5-fold between P9 and P27, a change that can be attributed to an increase in dendritic diameter during this developmental period. The developmental profile of the morphology of MSO neurons obtained indicates that maturation is reached 2 weeks after hearing onset. PMID:19760600

  5. Systematics and phylogeny of West African gerbils of the genus Gerbilliscus (Muridae: Gerbillinae) inferred from comparative G- and C-banding chromosomal analyses.

    PubMed

    Volobouev, V; Aniskin, V M; Sicard, B; Dobigny, G; Granjon, L

    2007-01-01

    Comparative analysis of the G- and C-banding patterns in six morphologically similar species of the genus Gerbilliscus(G. gambianus, G. guineae, G. kempi, Gerbilliscus sp., G. robustus and G. leucogaster) and one belonging to the genus Gerbillurus (G. tytonis) from 27 West, East and South African localities was carried out. Our study revealed that 17 rearrangements comprising seven fissions, five translocations and five inversions occurred in the evolution of this group, with 1-13 rearrangements differentiating the various species. In addition the unusually large sex chromosomes appear to be species-specific as judged by size and morphology reflecting structural rearrangements as well as the variable presence of a large amount of C-heterochromatin found in each species at a particular chromosomal location. These karyotypic features allow us to recognize five distinct species in West Africa (compared to the two recognized in recent taxonomic lists) and to roughly delimit their geographical distributions. The pattern of phylogenetic relationships inferred from a cladistic analysis of the chromosomal data is in good agreement with recent molecular phylogenetic studies that recognize a West African species group within the genus Gerbilliscus, and the monophyly of both Gerbilliscus and Gerbillurus. PMID:17431325

  6. Assessment of tissue distribution and concentration of ß-cryptoxanthin in reponse to varying amounts of dietary ß-cryptoxanthin in Mongolian gerbil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ß-cryptoxanthin is a precursor to vitamin A and has other potential health benefits. However, there is a lack of knowledge regarding its metabolism, storage, and dose-response effects. This study investigated the whole body metabolism of ß-cryptoxanthin in an appropriate small animal model for huma...

  7. Effect of 7-nitroindazole, a selective neuronal nitric oxide synthase inhibitor, on parvalbumin immunoreactivity after cerebral ischaemia in the hippocampus of the Mongolian gerbil.

    PubMed

    Kwon, Y B; Yoon, Y S; Han, H J; Lee, J H

    1999-12-01

    Previous studies have demonstrated that a loss of parvalbumin-immunoreactive (PV-ir) neurones is observed in the hippocampus after transient cerebral ischaemia. However, whether the loss of parvalbumin (PV) immunoreactivity is related to the over-production of nitric oxide (NO) during cerebral ischaemia has not been evaluated. This study was designed to test the effect of 7-nitroindazole pre-treatment (7-NI, 50 mg/kg), a selective neuronal NO synthase inhibitor, on PV immunoreactivity and its cellular activity following forebrain ischaemia. PV-ir neurones in the hippocampus of the control group were widely distributed in the pyramidal cell layer and stratum oriens of CA1 and CA3, and the granular cell layer of dentate gyrus. 7-NI pre-treatment completely suppressed the reduction of PV immunoreactivity in CA1 that was observed in the ischaemia-induced group. Subsequently, 7-NI pre-treatment also protected against the structural loss of microtubule-associated protein 2 (MAP2) immunoreactivity in CA1 after ischaemic insult. In addition, the Fos-defined neuronal activity of PV-ir neurones was slightly increased by the 7-NI pre-treatment 3 h after ischaemia. Based on these data, we conclude that the neuronal toxicity of NO may be involved in the loss of PV-ir neurones after cerebral ischaemia. PMID:10652828

  8. BESNOITIA ORYCTOFELISI N. SP. (PROTOZOA: APICOMPLEXA) FROM DOMESTIC RABBITS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A species of Besnoitia from naturally infected rabbits from Argentina was propagated experimentally in mice, gerbils, rabbits, cats, and cell cultures. Cats fed tissue cysts from rabbits shed oocysts with a prepatent period of nine to 13 days. Sporulated oocysts were infective to gerbils, rabbits,...

  9. Reversal of age-related increase in brain protein oxidation, decrease in enzyme activity, and loss in temporal and spatial memory by chronic administration of the spin-trapping compound N-tert-butyl-alpha-phenylnitrone

    SciTech Connect

    Carney, J.M.; Starke-Reed, P.E.; Oliver, C.N.; Landum, R.W.; Cheng, M.S.; Wu, J.F.; Floyd, R.A. )

    1991-05-01

    Oxygen free radicals and oxidative events have been implicated as playing a role in bringing about the changes in cellular function that occur during aging. Brain readily undergoes oxidative damage, so it is important to determine if aging-induced changes in brain may be associated with oxidative events. Previously we demonstrated that brain damage caused by an ischemia/reperfusion insult involved oxidative events. In addition, pretreatment with the spin-trapping compound N-tert-butyl-alpha-phenylnitrone (PBN) diminished the increase in oxidized protein and the loss of glutamine synthetase (GS) activity that accompanied ischemia/reperfusion injury in brain. We report here that aged gerbils had a significantly higher level of oxidized protein as assessed by carbonyl residues and decreased GS and neutral protease activities as compared to young adult gerbils. We also found that chronic treatment with the spin-trapping compound PBN caused a decrease in the level of oxidized protein and an increase in both GS and neutral protease activity in aged Mongolian gerbil brain. In contrast to aged gerbils, PBN treatment of young adult gerbils had no significant effect on brain oxidized protein content or GS activity. Male gerbils, young adults (3 months of age) and retired breeders (15-18 months of age), were treated with PBN for 14 days with twice daily dosages of 32 mg/kg. If PBN administration was ceased after 2 weeks, the significantly decreased level of oxidized protein and increased GS and neutral protease activities in old gerbils changed in a monotonic fashion back to the levels observed in aged gerbils prior to PBN administration. We also report that old gerbils make more errors than young animals and that older gerbils treated with PBN made fewer errors in a radial arm maze test for temporal and spatial memory than the untreated aged controls.

  10. 5. Historic American Buildings Survey, Pierre LeBoutillier and Trusten M. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey, Pierre LeBoutillier and Trusten M. Baldwin, Photographers, April, 1960 INTERIOR DETAIL, NORTHEAST AND SOUTHEAST PARLORS, ORIGINAL MANTEL (LEFT - RADIATOR COVERED). - King of Prussia Inn, U.S. Route 202 (Upper Merion Township), King of Prussia, Montgomery County, PA

  11. 1. GENERAL VIEW. NOTE THE FOLLOWING: STONE BUTTRESS ON STONE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL VIEW. NOTE THE FOLLOWING: STONE BUTTRESS ON STONE END, STONE COLUMNS ON FOREBAY. DATE STONE REMOVED IN 1914, BUT BARN MAY HAVE BEEN CONSTRUCTED IN THE 1830s - Barn, Beidler Road, Upper Merion Township, King of Prussia, Montgomery County, PA

  12. Saving a Progressive Vision: Moving the Barnes Collection

    ERIC Educational Resources Information Center

    Feinberg, Walter

    2013-01-01

    This paper examines the progressive understanding of art advanced by Albert Barnes, and asks how the educational vision for his large collection of art might be preserved as it has now moves from its location in the idyllic suburban setting in Merion, PA to the hustle and bustle of central Philadelphia. I submit that the vision will be endangered…

  13. Biology Notes

    ERIC Educational Resources Information Center

    School Science Review, 1977

    1977-01-01

    Includes procedures for demonstrating anaerobic respiration in peas, isolating virgin Drosophila females, solving mortality problems in young gerbils, measuring dissolved oxygen, constructing models for transpiration and DNA molecules, freezing chick embryos, mixing nutrient media, illustrating Darwinian ecological principles, and detecting…

  14. Predator facilitation or interference: a game of vipers and owls.

    PubMed

    Embar, Keren; Raveh, Ashael; Hoffmann, Ishai; Kotler, Burt P

    2014-04-01

    In predator-prey foraging games, the prey's reaction to one type of predator may either facilitate or hinder the success of another predator. We ask, do different predator species affect each other's patch selection? If the predators facilitate each other, they should prefer to hunt in the same patch; if they interfere, they should prefer to hunt alone. We performed an experiment in a large outdoor vivarium where we presented barn owls (Tyto alba) with a choice of hunting greater Egyptian gerbils (Gerbillus pyramidum) in patches with or without Saharan horned vipers (Cerastes cerastes). Gerbils foraged on feeding trays set under bushes or in the open. We monitored owl location, activity, and hunting attempts, viper activity and ambush site location, and the foraging behavior of the gerbils in bush and open microhabitats. Owls directed more attacks towards patches with vipers, and vipers were more active in the presence of owls. Owls and vipers facilitated each other's hunting through their combined effect on gerbil behavior, especially on full moon nights when vipers are more active. Owls forced gerbils into the bushes where vipers preferred to ambush, while viper presence chased gerbils into the open where they were exposed to owls. Owls and vipers took advantage of their indirect positive effect on each other. In the foraging game context, they improve each other's patch quality and hunting success. PMID:24481981

  15. Marked Antigiardial Activity of Yucca baccata Extracts: A Potential Natural Alternative for Treating Protozoan Infections

    PubMed Central

    Quihui-Cota, Luis; León-Trujillo, Rocio; Astiazarán-García, Humberto; Esparza-Romero, Julián; Robles, María del Refugio; Robles-Zepeda, Ramón E.; Canett, Rafael; Sánchez-Escalante, Jesús

    2014-01-01

    Human Giardiosis is a public health problem in Mexico, where the national prevalence was estimated to be up to 68%. Misuse of antiprotozoal drugs may result in low effectiveness and undesirable side effects. Research on natural products is a good strategy for discovering more effective antiparasitic compounds. This study evaluated the antigiardial activity of extracts of Yucca baccata, which is native to northwestern Mexico. Forty-two gerbils (females) were weighed and orally inoculated with 5 × 106 Giardia trophozoites. Two gerbils were selected at random to confirm infection. Forty living gerbils were randomly allocated into 5 treatment groups (8 per group). Gerbils were randomly assigned to be treated with 24.4 mg/mL, 12.2 mg/mL, and 6.1 mg/mL of extracts, metronidazole (2 mg/mL) or PBS, which were intragastrically administered once per day for 3 days. Nine gerbils died during the study course. On day 10 postinfection, gerbils were euthanized and trophozoites were quantified. Yucca extracts reduced, albeit not significantly, the trophozoite counts in the duodenum segment. Only the high-extract concentration significantly reduced the trophozoite counts in the proximal segment and it was similar to that of metronidazole. Extracts of Y. baccata may represent an effective and natural therapeutic alternative for human giardiosis. PMID:25250335

  16. Marked antigiardial activity of Yucca baccata extracts: a potential natural alternative for treating protozoan infections.

    PubMed

    Quihui-Cota, Luis; León-Trujillo, Rocio; Astiazarán-García, Humberto; Esparza-Romero, Julián; del Refugio Robles, María; Robles-Zepeda, Ramón E; Canett, Rafael; Sánchez-Escalante, Jesús

    2014-01-01

    Human giardiosis is a public health problem in Mexico, where the national prevalence was estimated to be up to 68%. Misuse of antiprotozoal drugs may result in low effectiveness and undesirable side effects. Research on natural products is a good strategy for discovering more effective antiparasitic compounds. This study evaluated the antigiardial activity of extracts of Yucca baccata, which is native to northwestern Mexico. Forty-two gerbils (females) were weighed and orally inoculated with 5 × 10(6) Giardia trophozoites. Two gerbils were selected at random to confirm infection. Forty living gerbils were randomly allocated into 5 treatment groups (8 per group). Gerbils were randomly assigned to be treated with 24.4 mg/mL, 12.2 mg/mL, and 6.1 mg/mL of extracts, metronidazole (2 mg/mL) or PBS, which were intragastrically administered once per day for 3 days. Nine gerbils died during the study course. On day 10 postinfection, gerbils were euthanized and trophozoites were quantified. Yucca extracts reduced, albeit not significantly, the trophozoite counts in the duodenum segment. Only the high-extract concentration significantly reduced the trophozoite counts in the proximal segment and it was similar to that of metronidazole. Extracts of Y. baccata may represent an effective and natural therapeutic alternative for human giardiosis. PMID:25250335

  17. Effects of EGFR Inhibitor on Helicobacter pylori Induced Gastric Epithelial Pathology in Vivo

    PubMed Central

    Crabtree, Jean E.; Jeremy, Anthony H.T.; Duval, Cedric; Dixon, Michael F.; Danjo, Kazuma; Carr, Ian M.; Pritchard, D. Mark; Robinson, Philip A.

    2013-01-01

    Helicobacter pylori transactivates the Epidermal Growth Factor Receptor (EGFR) and predisposes to gastric cancer development in humans and animal models. To examine the importance of EGFR signalling to gastric pathology, this study investigated whether treatment of Mongolian gerbils with a selective EGFR tyrosine kinase inhibitor, EKB-569, altered gastric pathology in chronic H. pylori infection. Gerbils were infected with H. pylori and six weeks later received either EKB-569-supplemented, or control diet, for 32 weeks prior to sacrifice. EKB-569-treated H. pylori-infected gerbils had no difference in H. pylori colonisation or inflammation scores compared to infected animals on control diet, but showed significantly less corpus atrophy, mucous metaplasia and submucosal glandular herniations along with markedly reduced antral and corpus epithelial proliferation to apoptosis ratios. EKB-569-treated infected gerbils had significantly decreased abundance of Cox-2, Adam17 and Egfr gastric transcripts relative to infected animals on control diet. EGFR inhibition by EKB-569 therefore reduced the severity of pre-neoplastic gastric pathology in chronically H. pylori-infected gerbils. EKB-569 increased gastric epithelial apoptosis in H. pylori-infected gerbils which counteracted some of the consequences of increased gastric epithelial cell proliferation. Similar chemopreventative strategies may be useful in humans who are at high risk of developing H. pylori- induced gastric adenocarcinoma. PMID:25437333

  18. Pathogenesis of Middle Ear Cholesteatoma

    PubMed Central

    Yamamoto-Fukuda, Tomomi; Hishikawa, Yoshitaka; Shibata, Yasuaki; Kobayashi, Toshimitsu; Takahashi, Haruo; Koji, Takehiko

    2010-01-01

    Middle ear cholesteatoma is characterized by enhanced proliferation of epithelial cells with aberrant morphological characteristics. To investigate the origin of the cholesteatoma cells, we analyzed spontaneously occurring cholesteatomas associated with a new transplantation model in Mongolian gerbils (gerbils). Cholesteatomas were induced in gerbils with a transplanted tympanic membrane by using the external auditory canal (EAC) ligation method. After the pars flaccida of the tympanic membranes were completely removed from male gerbils, corresponding portions of tympanic membranes of female gerbils were transplanted to the area of defect, and then we ligated the EAC (hybrid-model group). As a control group, the EAC of normal male and female gerbils was ligated without myringoplasty. In all ears of each group, the induced cholesteatomas were seen. In situ PCR was then performed to detect the mouse X chromosome-linked phosphoglycerate kinase-1 (pgk-1) gene on the paraffin sections. One pgk-1 spot in the epithelial nuclei was detected in male cholesteatoma, and two pgk-1 spots were detected in female cholesteatoma, respectively. On the other hand, in the hybrid-model group, we detected not only one but also two pgk-1 spots in the epithelial nuclei of cholesteatoma. These results strengthened the evidence that the origin of epithelial cells in cholesteatoma is the tympanic membrane in this model, but not the residential middle ear epithelial cells or the skin of the EAC. PMID:20413684

  19. Cochlear Modeling Using Time-Averaged Lagrangian" Method:. Comparison with VBM, PST, and ZC Measurements

    NASA Astrophysics Data System (ADS)

    Yoon, Y.; Kim, N.; Puria, S.; Steele, C. R.

    2009-02-01

    In this work, basilar membrane velocity (VBM), scala tympani intracochlear pressure (PST), and cochlear input impedances (Zc) for gerbil and chinchilla are implemented using a three-dimensional hydro-dynamic cochlear model using 1) time-averaged Lagrangian, 2) push-pull mechanism in active case, and 3) the complex anatomy of cochlear scalae by micro computed tomography (μCT) scanning and 3-D reconstructions of gerbil and chinchilla temporal bones. The objective of this work is to compare the calculations and the physiological measurements of gerbil and chinchilla cochlear such as VBM (Ren and Nuttall [1]), PST (Olson [2]), and ZC (Decraemer et al. [3], Songer and Rosowski [4], Ruggero et al. [5]) with present model. A WKB asymptotic method combined with Fourier series expansions is used to provide an efficient simulation. VBM and PST simulation results for the gerbil cochlea show good agreement both in the magnitude and the phase for the physiological measurements without larger phase excursion. ZC simulation from the gerbil and chinchilla model show reasonably good agreement with measurement.

  20. Viability of sporulated oocysts of Neospora caninum after exposure to different physical and chemical treatments.

    PubMed

    Alves Neto, Aldo F; Bandini, Luciana A; Nishi, Sandra M; Soares, Rodrigo M; Driemeier, David; Antoniassi, Nadia A B; Schares, Gereon; Gennari, Solange M

    2011-02-01

    The aim of the present study was to evaluate the viability of Neospora caninum sporulated oocysts after various chemical and physical treatments. Bioassays in gerbils and molecular techniques (PCR-RFLP) were used for identification of the oocysts shed by experimentally infected dogs. Sporulated oocysts were purified and divided into 11 treatment groups as follows: absolute ethanol for 1 hr; 20 C for 6 hr; 4 C for 6 hr; 60 C for 1 min; 100 C for 1 min; 10% formaldehyde for 1 hr; 10% ammonia for 1 hr; 2% iodine for 1 hr; 10% sodium hypochlorite for 1 hr; 70% ethanol for 1 hr; and one group was left untreated and kept as a positive control. All chemical treatments were performed at room temperature (37 C). A total of 33 gerbils, or 3 gerbils per treatment, were used for bioassays. After treatment, the oocysts were divided into aliquots of 1,000 oocysts and orally administered to gerbils. After 63 days, the gerbils were anesthetized and killed with 0.2 ml of T61; blood and tissue samples were collected for serological (IFAT and western blotting), molecular (real-time PCR), histopathology, and immunohistochemical tests. Treatments were considered effective only if all 5 detection techniques tested negative. High temperatures at 100 C for 1 min and 10% sodium hypochlorite for 1 hr were the only treatments that met this condition, effectively inactivating all oocysts. PMID:21348620

  1. Helminth parasites of small mammals in Kerman province, southeastern Iran.

    PubMed

    Fasihi Harandi, Majid; Madjdzadeh, Seyed Massoud; Ahmadinejad, Mohammad

    2016-03-01

    Fifty-one specimens of small mammals were collected from different locations of Kerman province, southeastern Iran during 2007 and 2009. They constitute six species of rodents (Meriones persicus, Meriones libycus, Tatera indica, Dryomys nitedula and Mus musculus), one species of Erinaceomorpha (Paraechinus hypomelas) and one species of hare (Lepus europeus). The rate of helminthic infection was 45.1 % among all trapped specimens. In 28 out of 51 hunted specimens no intestinal helminth parasite was found. Of all mammals examined, 15 (29.4 %) had nematodes, 5 (9.8 %) had cestodes, and 3 (5.9 %) were infected with Acanthocephala. Five different species of parasites were isolated: Trichuris muris, Moniliformis moniliformis, Hymenolepis diminuta, Hymenolepis nana, and Mastophorus muris. Results of the present study indicate the potential of small mammals in the transmission of zoonotic helminthic infection. PMID:27065607

  2. Coarse-resolution Ecology of Etiological Agent, Vector, and Reservoirs of Zoonotic Cutaneous Leishmaniasis in Libya

    PubMed Central

    Samy, Abdallah M.; Annajar, Badereddin B.; Dokhan, Mostafa Ramadhan; Boussaa, Samia; Peterson, A. Townsend

    2016-01-01

    Abstract Cutaneous leishmaniasis ranks among the tropical diseases least known and most neglected in Libya. World Health Organization reports recognized associations of Phlebotomus papatasi, Psammomys obesus, and Meriones spp., with transmission of zoonotic cutaneous leishmaniasis (ZCL; caused by Leishmania major) across Libya. Here, we map risk of ZCL infection based on occurrence records of L. major, P. papatasi, and four potential animal reservoirs (Meriones libycus, Meriones shawi, Psammomys obesus, and Gerbillus gerbillus). Ecological niche models identified limited risk areas for ZCL across the northern coast of the country; most species associated with ZCL transmission were confined to this same region, but some had ranges extending to central Libya. All ENM predictions were significant based on partial ROC tests. As a further evaluation of L. major ENM predictions, we compared predictions with 98 additional independent records provided by the Libyan National Centre for Disease Control (NCDC); all of these records fell inside the belt predicted as suitable for ZCL. We tested ecological niche similarity among vector, parasite, and reservoir species and could not reject any null hypotheses of niche similarity. Finally, we tested among possible combinations of vector and reservoir that could predict all recent human ZCL cases reported by NCDC; only three combinations could anticipate the distribution of human cases across the country. PMID:26863317

  3. Molecular phylogeny of pneumocystis based on 5.8S rRNA gene and the internal transcribed spacers of rRNA gene sequences.

    PubMed

    Li, ZiHui; Feng, XianMin; Lu, SiQi; Zhang, Fan; Wang, FengYun; Huang, Song

    2008-05-01

    To clarify the phylogenetic relationships and species status of Pneumocystis, the 5.8S rRNA gene and the internal transcribed spacers (ITS, 1 and 2) of Pneumocystis rRNA derived from rat, gerbil and human were amplified, cloned and sequenced. The genetic distance matrix of six Pneumocystis species compared with other fungi like Taphrina and Saccharomyces indicated that the Pneumocystis genus contained multiple species including Pneumocystis from gerbil. The phylogenetic tree also showed that Pneumocystis from human and monkey formed one group and four rodent Pneumocystis formed another group. Among the four members, Pneumocystis wakefieldiae was most closely related to Pneumocystis murina and Pneumocystis carinii, and was least related to gerbil Pneumocystis. PMID:18785590

  4. Infectivity of Cryptosporidium muris directly isolated from the murine stomach for various laboratory animals.

    PubMed

    Aydin, Y; Ozkul, I A

    1996-11-15

    Oocysts of Cryptosporidium muris, directly isolated from the stomach of experimentally infected laboratory mice were orally inoculated into rats, gerbils, guinea pigs, dogs, and rabbits. Weaned rats developed patent C. muris infection as evidenced by the endogenous stages in gastric glands and oocyst shedding 10-17 days later. No signs of clinical illness or macroscopic findings were detected in mice and rats. Laboratory raised suckling rabbits, guinea pigs, gerbils and dogs fed C. muris rarely developed patent infections and they were considered not a true host for C. muris. PMID:9017888

  5. Coccidian parasites (Apicomplexa: Eimeriidae) from insectivores. III. Seven new species in shrews (Soricidae: Soricinae) from Canada, Japan, and the United States.

    PubMed

    Hertel, L A; Duszynski, D W

    1987-02-01

    Since May 1979, 458 shrews (Blarina sp. and Sorex spp.) representing 20 species collected in Canada, Japan, and the United States were examined for coccidia; 110 (24%) had oocysts in their feces, including 8 of 21 (38%) B. brevicauda from Massachusetts, Ohio, Pennsylvania, and Vermont; 2 of 7 (29%) S. caecutiens from Hokkaido and Honshu; 14 of 63 (22%) S. cinereus from Colorado, New Mexico, Pennsylvania, Vermont, Manitoba, and Ontario; 3 of 7 (43%) S. fontinalis from Pennsylvania; 11 of 16 (69%) S. fumeus from Massachusetts, Minnesota, Pennsylvania, Vermont, and Ontario; 1 of 4 (25%) S. haydeni from Minnesota; 6 of 8 (75%) S. longirostris from Florida and Virginia; 1 of 2 (50%) S. ornatus from California; 5 of 12 (42%) S. pacificus from California and Oregon; 13 of 41 (32%) S. palustris from California, Colorado, and New Mexico; 1 of 2 (50%) S. tenellus from California; 11 of 105 (10%) S. trowbridgii from California, Oregon, and Washington; 10 of 48 (21%) S. unguiculatus from Hokkaido; and 24 of 112 (21%) S. vagrans from Arizona, California, Colorado, New Mexico, Oregon, and Washington. The following coccidians were identified from infected shrews: Eimeria brevicauda n. sp. from B. brevicauda; Eimeria fumeus n. sp. from S. fumeus, S. pacificus, S. unguiculatus, and S. vagrans; Eimeria inyoni n. sp. from S. tenellus; Eimeria palustris n. sp. from S. cinereus, S. fontinalis, S. fumeus, S. haydeni, S. longirostris, S. ornatus, S. pacificus, S. palustris, S. tenellus, S. trowbridgii, and S. vagrans; Eimeria vagrantis n. sp. from S. fumeus, S. trowbridgii, and S. vagrans; Isospora brevicauda n. sp. from B. brevicauda; and Isospora palustris n. sp. from S. pacificus, S. palustris, S. trowbridgii, S. unguiculatus, and S. vagrans. The world literature on coccidian parasites of shrews (16 eimerians and 3 isosporans exclusive of the 7 new species described here) is reviewed. PMID:3572649

  6. Why Training Fails (And What to Do about It).

    ERIC Educational Resources Information Center

    Hendon, David H.; Barlow, Judith L.

    1985-01-01

    Presents (with tongue in cheek) a four-style behavior model guaranteed to produce excellence in the four types of trainees: nematodes (docile but learn nothing), gerbils (fond of noncompetitive games and hugging), warthogs (like to attend expensive seminars), and Cro-Magnon (like to interpret to others as opposed to actually learning anything…

  7. Science Learning Experience Involving Adults and Their Preadolescent and Adolescent Children.

    ERIC Educational Resources Information Center

    Gennaro, Eugene D.; And Others

    1980-01-01

    Describes a five-week course in animal behavior for parents and their middle-school-aged children offered at the Minnesota Zoological Garden. Course activities included discussions, film viewing, demonstrations, zoo observations, and home studies of gerbils or zebra finches. Results of the course are discussed. (CS)

  8. A Science Assessment Program for Kindergarten and First Grade Students.

    ERIC Educational Resources Information Center

    Greening, Gary A.

    Presented are science units for kindergarten and first-grade classes which include one or more non-verbal test items constructed to determine whether the student has learned the material presented in the unit. Units include: light, senses, gerbils, beans and peas, animal activities, and hatching chicks. (SL)

  9. 77 FR 28799 - Animal Welfare; Retail Pet Stores and Licensing Exemptions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-16

    ... the number of breeding female dogs, cats, and/or small exotic or wild mammals that a person may... as pets are considered retail pet stores: Dogs, cats, rabbits, guinea pigs, hamsters, gerbils, rats..., dogs, or cats, and who derives no more than $500 gross income from the sale of such animals....

  10. The role of depressed metabolism in increased radio resistance

    NASA Technical Reports Server (NTRS)

    Musacchia, X. J.

    1972-01-01

    Studies are presented of the physiology of depressed metabolism, radio-resistance in depressed metabolic states, comparative aspects of depressed metabolism, and gastrointestinal responses to ionizing radiation. Specific data cover helium-cold induced hypothermia in white rats and hamsters, and radiation responses and intestinal absorption in the gerbil.

  11. Classroom Critters and the Scientific Method.

    ERIC Educational Resources Information Center

    Kneidel, Sally

    This resource book presents 37 behavioral experiments that can be performed with commonly-found classroom animals including hamsters, gerbils, mice, goldfish, guppies, anolis lizards, kittens, and puppies. Each experiment explores the five steps of the scientific method: (1) Question; (2) Hypothesis; (3) Methods; (4) Result; and (5) Conclusion.…

  12. MtDNA CytB Structure of Rhombomys opimus (Rodentia: Gerbellidae), the Main Reservoir of Cutaneous Leishmaniasis in the Borderline of Iran-Turkmenistan

    PubMed Central

    Bakhshi, Hasan; Oshaghi, Mohammad Ali; Abai, Mohammad Reza; Rassi, Yavar; Akhavan, Amir Ahmad; Mohebali, Mehdi; Hajaran, Homa; Mohtarami, Fatemeh; Mirzajani, Hossein; Maleki-Ravasan, Naseh

    2013-01-01

    Background: Great gerbils, Rhombomys opimus, are the main reservoir host of zoonootic cutaneous leishmaniasis (ZCL) in Iran and neighboring countries. Based on morphological traits two subspecies R. opimus sodalis and R. opimus sargadensis have reported in the country. However, variation in infection rate and signs to Leishmania parasites, phenotype, size, and sexual polymorphisms demand more details to elucidate clearly the role of great gerbils in ZCL epidemiology. Methods: PCR-RFLP and PCR-direct sequencing were used to analyze mitochondrial DNA cytochrome B (mtDNA-cytB) gene structure of R. opimus collected from Golestan and Khorasan-e-Razavi Provinces in 2011 that are neighbor to Turkmenistan Country where ZCL is endemic in both sides of the borderline. Results: All of the specimens (n= 61) were morphologically or genetically similar to the typical R. opimus sodalis. However, there were 9 (1.5%) DNA substitutions throughout the 583 bp of the Cyt b gene of the samples sequenced comprising six DNA haplotypes. Maximum likelihood or neighbor joining phylogenetic trees inferred from the sequences could resolve the populations according to their subspecies as well as geographical origins. Discussion: The DNA polymorphisms in the great gerbils may correspond to the signs and infection rate in the animal. However, further studies are needed to match these six haplotypes with different signs and parasite sustaining following infection with L. major in the great gerbils. PMID:24409443

  13. Anti-Helicobacter pylori Properties of GutGard™

    PubMed Central

    Kim, Jae Min; Zheng, Hong Mei; Lee, Boo Yong; Lee, Woon Kyu; Lee, Don Haeng

    2013-01-01

    Presence of Helicobacter pylori is associated with an increased risk of developing upper gastrointestinal tract diseases. Antibiotic therapy and a combination of two or three drugs have been widely used to eradicate H. pylori infections. Due to antibiotic resistant drugs, new drug resources are needed such as plants which contain antibacterial compounds. The aim of this study was to investigate the ability of GutGard™ to inhibit H. pylori growth both in Mongolian gerbils and C57BL/6 mouse models. Male Mongolian gerbils were infected with the bacteria by intragastric inoculation (2×109 CFU/gerbil) 3 times over 5 days and then orally treated once daily 6 times/week for 8 weeks with 15, 30 and 60 mg/kg GutGard™. After the final administration, biopsy samples of the gastric mucosa were assayed for bacterial identification via urease, catalase and ELISA assays as well as immunohistochemistry (IHC). In the Mongolian gerbil model, IHC and ELISA assays revealed that GutGard™ inhibited H. pylori colonization in gastric mucosa in a dose dependent manner. The anti-H. pylori effects of GutGard™ in H. pylori-infected C57BL/6 mice were also examined. We found that treatment with 25 mg/kg GutGard™ significantly reduced H. pylori colonization in mice gastric mucosa. Our results suggest that GutGard™ may be useful as an agent to prevent H. pylori infection. PMID:24471118

  14. Effect of a water-rich diet on adrenal zona glomerulosa in Gerbillus tarabuli.

    PubMed

    Saadi, Leila; Lebaili, Nemcha

    2012-02-01

    The objective of this work is to evaluate the aldosterone level and to study the gerbil adrenal zona glomerulosa morphology in the presence of an important water diet content during seven days. Thirty adult gerbils, Gerbilus tarabuli, were randomly assigned to two watering regimes, with fifteen gerbils per group. The first group was the control and the second group was exposed to a water-rich diet during seven days. Thin sections of the adrenal glands were observed in photonic and electron microscopy. Their blood was sampled and analyzed for aldosterone, electrolyte concentrations and hematocrit. Urine was collected after 24hours. A water-rich diet decreased the body weight but increased the hematocrit, total protein, aldosterone concentration and urine volume. In electronic microscopy, the adrenal zona glomerulosa cells present a decrease in lipid compartment and Golgi apparatus zone development. The blood electrolyte concentrations were not changed significantly. These findings indicate that the water-rich diet exerts a potent stimulatory effect on aldosterone secretion by the gerbil adrenal zona glomerulosa through plasma volume perturbation. PMID:22325562

  15. The Color of the Wind: Fables for a New Age.

    ERIC Educational Resources Information Center

    Nottingham, Theodore J.

    This book of fables from the animal kingdom contains: "The Frog Who Knew Too Much"; "Long Tail the Lizard"; "The Otter Who Went to the Bottom of the Sea"; "The Single-Wattled Cassowary and His Lethal Toe"; "The Rebel Gerbil"; "Why Hairless Monkeys Turn Out So Bad"; and "The Eagles' Watchtower." The book has been tested with elementary, middle…

  16. Biology. USMES Beginning "How To" Set.

    ERIC Educational Resources Information Center

    Agro, Sally; And Others

    In this set of two booklets for primary grades, students learn how to make a home for their animals (amphibians, insects, fish, crayfish) and a home for their rodents (hamsters, guinea pigs, gerbils, mice). The major emphasis in all Unified Sciences and Mathematics for Elementary Schools (USMES) units is on open-ended, long-range investigations of…

  17. Common Emergencies in Small Rodents, Hedgehogs, and Sugar Gliders.

    PubMed

    McLaughlin, Alicia; Strunk, Anneliese

    2016-05-01

    Small exotic mammal pets such as rats, mice, hamsters, gerbils, degus, hedgehogs, and sugar gliders are becoming more popular. Because these animals are prone to a variety of health problems, and require specialized husbandry care to remain healthy, they may present to emergency hospitals in critical condition. This article provides a basic overview of common emergency presentations of these species. PMID:27131160

  18. Infectivity of Giardia lamblia cysts obtained from wastewater treated with ultraviolet light.

    PubMed

    Li, Dong; Craik, Stephen A; Smith, Daniel W; Belosevic, Miodrag

    2009-07-01

    Several waterborne outbreaks of giardiasis have been linked to discharge of wastewater effluents into surface water. Little is known about the infectivity of Giardia lamblia cysts present in UV treated wastewater effluents. In this study, the infectivity of G. lamblia cysts, recovered from primary effluent and secondary effluent, both upstream and downstream of operating full-scale UV reactors at four wastewater treatment plants, was assessed using the Mongolian gerbil model. Infectivity of cysts obtained from the primary effluents was scored as either strong or moderate for induction of infection in gerbils at three out of four wastewater treatment plants. G. lamblia recovered from secondary effluent both upstream and downstream of the UV reactors caused weak infections in the gerbils. The probability of weak infections caused by inoculums of 50-1400 cysts per gerbil was, on the average, reduced by approximately 10% at the four wastewater UV installations with coliform reduction equivalent doses ranging from 6 to 18 mJ/cm2. The UV systems provided considerably less inactivation of the parasite than expected based on the UV dose response of Giardia reported in the literature. PMID:19467689

  19. Talking with Children about Furry Classroom Pets.

    ERIC Educational Resources Information Center

    Texas Child Care, 1994

    1994-01-01

    Notes that rodents and rabbits share many characteristics that make them suitable classroom pets and gives background information on rabbits, guinea pigs, hamsters, and gerbils. Offers advice on buying a classroom pet, the pet's home, feeding, helping the children handle the pet, and pet health and family planning. (TJQ)

  20. Nutrient Requirements of Domestic Animals, Number 10: Nutrient Requirements of Laboratory Animals. Third Revised Edition, 1978.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Board on Agricultural and Renewable Resources.

    This report deals with the nutrient requirements of seven species of animals used extensively for biomedical research in the United States. Following an introductory chapter of general information on nutrition, chapters are presented on the nutrient requirements of the laboratory rat, mouse, gerbil, guinea pig, hamster, vole, and fishes. Each…

  1. Cats, Dogs, and Classroom Pets: Science in Art, Song, and Play.

    ERIC Educational Resources Information Center

    Vansant, Rhonda; Dondiego, Barbara L.

    Studying pets fosters children's natural curiosity about the world around them and encourages them to use their five senses. This cross-curricular guide provides opportunities for children to build concepts by introducing them to a variety of household pets beginning with cats and dogs, and including mice, gerbils, hamsters, rabbits, guinea pigs,…

  2. An improved insecticidal activity of silver nanoparticle synthesized by using Sargassum muticum.

    PubMed

    Moorthi, P Vinayaga; Balasubramanian, C; Mohan, S

    2015-01-01

    A highly active silver nanoparticle (SmAgNps) was synthesized in the present study by using Sargassum muticum extract. The instrumentations such as scanning electron microscope (SEM), energy dispersive X-ray (EDAX), and X-ray diffraction (XRD) were used to reveal the nanoparticle morphology and size. The insecticidal activities of SmAgNps against Ergolis merione reveals prominent changes in the protein profile of hemolymph, morphology of hemocytes, and deteriorated midgut inclusions such as lumen, basement membrane, fat body, and gastric caeca. From this study, it was observed that phytochemicals of S. muticum was a prominent precursor for the synthesis of highly active nanoparticles. PMID:25240853

  3. Influences on the stable oxygen and carbon isotopes in gerbillid rodent teeth in semi-arid and arid environments: Implications for past climate and environmental reconstruction

    NASA Astrophysics Data System (ADS)

    Jeffrey, Amy; Denys, Christiane; Stoetzel, Emmanuelle; Lee-Thorp, Julia A.

    2015-10-01

    The stable isotope composition of small mammal tissues has the potential to provide detailed information about terrestrial palaeoclimate and environments, because their remains are abundant in palaeontological and archaeological sites, and they have restricted home ranges. Applications to the Quaternary record, however, have been sparse and limited by an acute lack of understanding of small mammal isotope ecology, particularly in arid and semi-arid environments. Here we document the oxygen and carbon isotope composition of Gerbillinae (gerbil) tooth apatite across a rainfall gradient in northwestern Africa, in order to test the relative influences of the 18O/16O in precipitation or moisture availability on gerbil teeth values, the sensitivity of tooth apatite 13C/12C to plant responses to moisture availability, and the influence of developmental period on the isotopic composition of gerbil molars and incisors. The results show that the isotopic composition of molars and incisors from the same individuals differs consistent with the different temporal periods reflected by the teeth; molar teeth are permanently rooted and form around the time of birth, whereas incisors grow continuously. The results indicate that tooth choice is an important consideration for applications as proxy Quaternary records, but also highlights a new potential means to distinguish seasonal contexts. The oxygen isotope composition of gerbil tooth apatite is strongly correlated with mean annual precipitation (MAP) below 600 mm, but above 600 mm the teeth reflect the oxygen isotope composition of local meteoric water instead. Predictably, the carbon isotope composition of the gerbil teeth reflected C3 and C4 dietary inputs, however arid and mesic sites could not be distinguished because of the high variability displayed in the carbon isotope composition of the teeth due to the microhabitat and short temporal period reflected by the gerbil. We show that the oxygen isotope composition of small

  4. [Experimental evidence of an antihypertensive and hypocholesterolemic effect of oil of argan, Argania sideroxylon].

    PubMed

    Berrada, Y; Settaf, A; Baddouri, K; Cherrah, A; Hassar, M

    2000-01-01

    The chronic ingestion of 5 ml/kg/d of Argan oil by spontaneously hypertensive rats restores normal blood pressure and induces hypocholesterolaemia. In order to confirm these results Meriones shawi, a rodent of the Gerbillideae family, was tested as a second animal model. Meriones submitted to a hypercaloric diet and physical inactivity became fat, and exhibited hypertension, dyslipidaemia and hyperinsulinaemia. When treated for two months with the same dosage regimen, decreases in glycaemia, total plasmatic cholesterol, LDL, insulinaemia and systolic and diastolic blood pressures of 4.4 per cent, 14.4 per cent, 32.5 per cent, 26.8 per cent, 28.8 per cent and 30.5 per cent were simultaneously observed. Increases in LDH and of TG of 27.9 per cent and 16.2 per cent respectively were also observed. No effect on body weight occurred. The action of polyunsatured fatty acids of the Argan oil is predominant, but in addition, other constituents play an active part. PMID:10967715

  5. The effects of D-allose on transient ischemic neuronal death and analysis of its mechanism.

    PubMed

    Liu, Yanan; Nakamura, Takehiro; Toyoshima, Tetsuhiko; Shinomiya, Aya; Tamiya, Takashi; Tokuda, Masaaki; Keep, Richard F; Itano, Toshifumi

    2014-10-01

    The present study investigates the neuroprotective effects of d-allose, a rare sugar, against ischemia/reperfusion injury in a gerbil model. Transient forebrain ischemia was induced by occlusion of the bilateral common carotid arteries for 5 min. D-Allose was intravenously injected before and after ischemia (200 mg/kg). Extracellular glutamate and lactate release from the gerbil brain, and PO₂ profiles were monitored during ischemia and reperfusion. We also examined neuronal death and oxidative damage in the hippocampus one week after ischemia reperfusion, and investigated functional outcome. D-Allose administration suppressed glutamate and lactate release compared to vehicle controls. Brain damage, 8-OHdG levels (a marker of oxidative stress) and locomotor activities were significantly decreased by D-allose treatment. The present results suggest that d-allose reduces delayed neuronal death and behavioral deficits after transient ischemia by changing cerebral metabolism and inhibiting oxidative stress. PMID:25445611

  6. Plague dynamics are driven by climate variation

    PubMed Central

    Stenseth, Nils Chr.; Samia, Noelle I.; Viljugrein, Hildegunn; Kausrud, Kyrre Linné; Begon, Mike; Davis, Stephen; Leirs, Herwig; Dubyanskiy, V. M.; Esper, Jan; Ageyev, Vladimir S.; Klassovskiy, Nikolay L.; Pole, Sergey B.; Chan, Kung-Sik

    2006-01-01

    The bacterium Yersinia pestis causes bubonic plague. In Central Asia, where human plague is still reported regularly, the bacterium is common in natural populations of great gerbils. By using field data from 1949–1995 and previously undescribed statistical techniques, we show that Y. pestis prevalence in gerbils increases with warmer springs and wetter summers: A 1°C increase in spring is predicted to lead to a >50% increase in prevalence. Climatic conditions favoring plague apparently existed in this region at the onset of the Black Death as well as when the most recent plague pandemic arose in the same region, and they are expected to continue or become more favorable as a result of climate change. Threats of outbreaks may thus be increasing where humans live in close contact with rodents and fleas (or other wildlife) harboring endemic plague. PMID:16924109

  7. Cross-reactivity of secondary antibodies against African rodents and application for sero-surveillance.

    PubMed

    Nakamura, Ichiro; Hang'ombe, Bernard Mudenda; Sawa, Hirofumi; Kobayashi, Shintaro; Orba, Yasuko; Ishii, Akihiro; Thomas, Yuka; Isozumi, Rie; Yoshimatsu, Kumiko; Mweene, Aaron S; Takada, Ayato; Sugimoto, Chihiro; Arikawa, Jiro

    2013-01-01

    A total of 466 rodents were captured in the Republic of Zambia from 2006 to 2010. Based on morphological observations and phylogenetic analyses of mitochondrial gene sequences, rodents were divided into 10 groups consisting of 39 Rattus rodents, 263 multimammate rats, 18 other Murinae rodents, 95 gerbils, 11 pouched mice, 1 giant-pouched rat, 38 fat mice and 1 dormouse. Rodent antibodies except that from Rattus were examined for their cross-reactivity to commercially available antibody detection reagents. Anti-mouse immunoglobulin G (IgG) was most cross-reactive to heterologous antibodies including multimammate rat, gerbil, pouched mouse and fat mouse. Thus, anti-mouse IgG would be a useful detection tool in serological examination of the Zambian rodent population. Preliminary sero-surveillance for plague, leptospirosis and hantavirus infection was performed by ELISA. PMID:23386359

  8. Role of cerebral blood volume changes in brain specific-gravity measurements

    SciTech Connect

    Picozzi, P.; Todd, N.V.; Crockard, A.H.

    1985-05-01

    Cerebral blood volume (CBV) was calculated in gerbils from specific-gravity (SG) changes between normal and saline-perfused brains. Furthermore, changes in CBV were investigated during ischemia using carbon-14-labeled dextran (MW 70,000) as an intravascular marker. Both data were used to evaluate the possible error due to a change in CBV on the measurement of ischemic brain edema by the SG method. The methodological error found was 0.0004 for a 100% CBV change. This error is insignificant, being less than the standard deviation in the SG measured for the gerbil cortex. Thus, CBV changes are not responsible for the SG variations observed during the first phase of ischemia. These variations are better explained as an increase of brain water content during ischemia.

  9. Viruses other than arenaviruses from West African wild mammals

    PubMed Central

    Kemp, Graham E.

    1975-01-01

    At least thirty-seven different viruses have been isolated from wild mammals in West Africa since 1962. Some of these, including Lassa virus, are already known to cause serious human morbidity and mortality. Crimean haemorrhagic fever-Congo virus, Dugbe virus, Mokola virus, and a smallpox-like agent from a gerbil in Dahomey are briefly discussed. An account of social and ecologic factors affecting man, domestic animals, and their interaction with wild mammals is given. PMID:1085217

  10. Development of a laboratory animal model for infectious bovine keratoconjunctivitis.

    PubMed

    Chandler, R L; Turfrey, B A; Smith, K

    1982-01-01

    Guinea pigs, gerbils, voles, golden hamsters and Chinese hamsters exposed to experimental infection with Moraxella bovis by ocular instillation or associated routes showed transient infections only and no clinical signs. Five strains of mice were of similarly low susceptibility but another, the C57 Bl strain, was relatively susceptible and treatment with corticosteroid before infection regularly produced keratoconjunctivitis. This system therefore offers a promising model for studies on infectious bovine keratoconjunctivitis. PMID:7045996

  11. Investigation of otolith responses using ground based vestibular research facility

    NASA Technical Reports Server (NTRS)

    Correia, Manning J.; TABARACCI

    1989-01-01

    The general goal was to examine tilt sensitivity of horizontal semicircular canal afferents. Computer programs were tested which controlled the short axis centrifuge at the Vestibular Research Facility, acquired action potentials and produced data reduction analyses including histograms and gain and phase calculations. A pre-amplifier was also developed for the acquisition of action potentials. The data were gathered that can be used to contribute toward the understanding of the tilt sensitivity of semicircular canal afferents in the unanesthetized gerbil preparation.

  12. Anatomical features for an adequate choice of experimental animal model in biomedicine: II. Small laboratory rodents, rabbit, and pig.

    PubMed

    Lossi, Laura; D'Angelo, Livia; De Girolamo, Paolo; Merighi, Adalberto

    2016-03-01

    The anatomical features distinctive to each of the very large array of species used in today's biomedical research must be born in mind when considering the correct choice of animal model(s), particularly when translational research is concerned. In this paper we take into consideration and discuss the most important anatomical and histological features of the commonest species of laboratory rodents (rat, mouse, guinea pig, hamster, and gerbil), rabbit, and pig related to their importance for applied research. PMID:26527557

  13. Protection against oxidative damage to CNS by alpha-phenyl-tert-butyl nitrone (PBN) and other spin-trapping agents: A novel series of nonlipid free radical scavengers

    SciTech Connect

    Carney, J.M.; Floyd, R.A. )

    1991-01-01

    Brain is extremely susceptible to oxidative damage. Utilizing a series of novel approaches, the authors have demonstrated that oxidative damage occurs during an ischemia/reperfusion insult (IRI) to brain. Thus, they have demonstrated that an IRI to Mongolian gerbil brain results in: (1) an enhanced rate of salicylate hydroxylation, implicating an increased flux of hydroxyl free radicals; (2) an enhanced flux of free radicals as determined by spin-trapping; (3) an enhanced level of endogenous protein oxidation; (4) a decrease in glutamine synthetase (GS) activity, an enzyme very sensitive to oxidative damage; and (5) demonstration of protection from an IRI by administering the spin-trapping agent alpha-phenyl-tert-butyl nitrone (PBN). The novel observation that PBN offers protection from the lethality brought on by a brain IRI appears to be clearly linked to the ability of the administered spin-trap to inhibit oxidative damage as evidenced by the decreased amount of brain protein oxidation and the prevention of an IRI-mediated loss of GS activity in treated animals. Aged gerbils are more sensitive to the lethal action of a brain IRI than younger animals, but they are protected by PBN administration as are the younger animals. Older gerbils have a significantly higher level of oxidized protein in the brain. Older gerbils have decreased activities of GS and neutral protease, the enzyme that removes oxidized protein, than younger animals. Chronic twice daily administration of PBN (32 mg/kg) for 14 days to older animals significantly lowered brain oxidized protein levels and raised GS and neutral protease activity to those observed in younger animals. Cessation of PBN administration resulted in a time-dependent restoration of protein oxidation levels and enzyme activities back to those observed prior to spin-trap administration.

  14. Susceptibility of Laboratory Rodents to Trichinella papuae

    PubMed Central

    Sadaow, Lakkhana; Intapan, Pewpan M.; Boonmars, Thidarut; Morakote, Nimit

    2013-01-01

    Members of the genus Trichinella are small nematodes that can infect a wide range of animal hosts. However, their infectivity varies depending on the parasite and host species combination. In this study, we examined the susceptibility of 4 species of laboratory rodents, i.e., mice, rats, hamsters, and gerbils to Trichinella papuae, an emerging non-encapsulated Trichinella species. Trichinella spiralis and Trichinella pseudospiralis were also included in this study for comparison. Fifteen animals of each rodent species were infected orally with 100 muscle larvae of each Trichinella species. Intestinal worm burden was determined at day 6 and 10 post-inoculation (PI). The numbers of muscle larvae were examined at day 45 PI. The reproductive capacity index (RCI) of the 3 Trichinella species in different rodent hosts was determined. By day 6 PI, 33.2-69.6% of the inoculated larvae of the 3 Trichinella species became adult worms in the small intestines of the host animals. However, in rats, more than 96% of adult worms of all 3 Trichinella species were expelled from the gut by day 10 PI. In gerbils, only 4.8-18.1% of adult worms were expelled by day 10 PI. In accordance with the intestinal worm burden and the persistence of adults, the RCI was the highest in gerbils with values of 241.5±41.0 for T. papuae, 432.6±48 for T. pseudospiralis, and 528.6±20.6 for T. spiralis. Hamsters ranked second and mice ranked third in susceptibility in terms of the RCI, Rats yielded the lowest parasite RCI for all 3 Trichinella species. Gerbils may be an alternative laboratory animal for isolation and maintenance of Trichinella spp. PMID:24516265

  15. Susceptibility of laboratory rodents to Trichinella papuae.

    PubMed

    Sadaow, Lakkhana; Intapan, Pewpan M; Boonmars, Thidarut; Morakote, Nimit; Maleewong, Wanchai

    2013-12-01

    Members of the genus Trichinella are small nematodes that can infect a wide range of animal hosts. However, their infectivity varies depending on the parasite and host species combination. In this study, we examined the susceptibility of 4 species of laboratory rodents, i.e., mice, rats, hamsters, and gerbils to Trichinella papuae, an emerging non-encapsulated Trichinella species. Trichinella spiralis and Trichinella pseudospiralis were also included in this study for comparison. Fifteen animals of each rodent species were infected orally with 100 muscle larvae of each Trichinella species. Intestinal worm burden was determined at day 6 and 10 post-inoculation (PI). The numbers of muscle larvae were examined at day 45 PI. The reproductive capacity index (RCI) of the 3 Trichinella species in different rodent hosts was determined. By day 6 PI, 33.2-69.6% of the inoculated larvae of the 3 Trichinella species became adult worms in the small intestines of the host animals. However, in rats, more than 96% of adult worms of all 3 Trichinella species were expelled from the gut by day 10 PI. In gerbils, only 4.8-18.1% of adult worms were expelled by day 10 PI. In accordance with the intestinal worm burden and the persistence of adults, the RCI was the highest in gerbils with values of 241.5±41.0 for T. papuae, 432.6±48 for T. pseudospiralis, and 528.6±20.6 for T. spiralis. Hamsters ranked second and mice ranked third in susceptibility in terms of the RCI, Rats yielded the lowest parasite RCI for all 3 Trichinella species. Gerbils may be an alternative laboratory animal for isolation and maintenance of Trichinella spp. PMID:24516265

  16. Cochlear anatomy using micro computed tomography (μCT) imaging

    NASA Astrophysics Data System (ADS)

    Kim, Namkeun; Yoon, Yongjin; Steele, Charles; Puria, Sunil

    2008-02-01

    A novel micro computed tomography (μCT) image processing method was implemented to measure anatomical features of the gerbil and chinchilla cochleas, taking into account the bent modailosis axis. Measurements were made of the scala vestibule (SV) area, the scala tympani (SV) area, and the basilar membrane (BM) width using prepared cadaveric temporal bones. 3-D cochlear structures were obtained from the scanned images using a process described in this study. It was necessary to consider the sharp curvature of mododailosis axis near the basal region. The SV and ST areas were calculated from the μCT reconstructions and compared with existing data obtained by Magnetic Resonance Microscopy (MRM), showing both qualitative and quantitative agreement. In addition to this, the width of the BM, which is the distance between the primary and secondary osseous spiral laminae, is calculated for the two animals and compared with previous data from the MRM method. For the gerbil cochlea, which does not have much cartilage in the osseous spiral lamina, the μCT-based BM width measurements show good agreement with previous data. The chinchilla BM, which contains more cartilage in the osseous spiral lamina than the gerbil, shows a large difference in the BM widths between the μCT and MRM methods. The SV area, ST area, and BM width measurements from this study can be used in building an anatomically based mathematical cochlear model.

  17. Viremia and antibody response of small African and laboratory animals to Crimean-Congo hemorrhagic fever virus infection.

    PubMed

    Shepherd, A J; Leman, P A; Swanepoel, R

    1989-05-01

    Eleven species of small African wild mammals, laboratory rabbits, guinea pigs, and Syrian hamsters were infected with Crimean-Congo hemorrhagic fever (CCHF) virus. Low-titered viremia followed by development of antibody was observed in scrub hares (Lepus saxatilis), Cape ground squirrels (Xerus inauris), red veld rats (Aethomys chrysophilus), white tailed rats (Mystromys albicaudatus), bushveld gerbils (Tatera leucogaster), striped mice (Rhabdomys pumilio), and guinea pigs. The maximum viremic titer in 4 scrub hares was 10(1.7-4.2) 50% mouse lethal doses/ml. Viremia was detected in 1/17 infected laboratory rabbits. Antibody response was only detected in South African hedgehogs (Atelerix frontalis), highveld gerbils (T. brantsii), Namaqua gerbils (Desmodillus auricularis), 2 species of multimammate mouse (Mastomys natalensis and M. coucha), and Syrian hamsters. The results of the study indicate that a proportion of infected scrub hares develop CCHF viremia of an intensity shown in the Soviet Union to be sufficient for infection of feeding immature ixodid ticks, but that South African hedgehogs and wild rodents are unlikely to be of importance as maintenance hosts of the virus in southern Africa. PMID:2499205

  18. Free radical damage to protein and DNA: mechanisms involved and relevant observations on brain undergoing oxidative stress.

    PubMed

    Floyd, R A; Carney, J M

    1992-01-01

    Iron mediates damage to proteins and DNA. The mechanisms of damage not only involve iron but also oxygen free radical intermediates. Oxidative damage to DNA causes not only strand breaks, but also formation of specific base adducts, such as 8-hydroxy-2'-deoxyguanosine. Oxidative damage also inactivates certain enzymes such as glutamine synthetase. Novel methods of assessing oxidative damage to tissue, including quantitation of salicylate hydroxylation as an index of hydroxyl free radical flux as well as specific lesions to proteins and DNA, have yielded results that clearly show that ischemia/reperfusion injury to mongolian gerbil brain involves oxidatively damaging events. Aging in gerbil as well as human brain is also associated with increased oxidative damage. Recent novel observations have shown that the spin-trapping agent phenyl alpha-tert-butylnitrone (PBN) offers protection in gerbil brain during ischemia/reperfusion injury. We also show that oxidative damage to brain during aging is decreased by chronic administration of PBN. The mechanism of action of PBN may be related to its trapping of specific free radicals, which triggers a cascade of oxidative events that eventually lead to tissue injury. PMID:1510377

  19. Baicalin alleviates ischemia-induced memory impairment by inhibiting the phosphorylation of CaMKII in hippocampus.

    PubMed

    Wang, Peng; Cao, Yonggang; Yu, Juan; Liu, Ruxia; Bai, Bing; Qi, Hanping; Zhang, Qianlong; Guo, Wenguang; Zhu, Hui; Qu, Lihui

    2016-07-01

    Baicalin has a significant neuroprotective effect in stroke. However, the mechanism remains unclear. This study was to reveal the mechanisms by which baicalin protected hippocampal neurons and improved learning and memory impairment after global cerebral ischemia/reperfusion in gerbil. In the present study, the Morris water maze test showed that baicalin significantly improved learning and memory impairment after global cerebral ischemia/reperfusion in gerbils. Laser scanning confocal fluorescence microscope examination showed that baicalin suppressed OGD-induced augmentation of intracellular calcium concentration. Western blotting analysis indicated that baicalin suppressed ischemia-caused elevated phosphorylation level of CaMKII in vivo, in hippocampal neurons in culture, and in SH-SY5Y cells in culture. Western blotting, TUNEL and RNA interference technology were applied to detect effects of baicalin on neuronal apoptosis. We found that baicalin, a CaMKII inhibitor and knocking down the CaMKII prevented OGD-induced apoptosis of hippocampal or SH-SY5Y cells in culture. Therefore, these results suggested that baicalin improves learning and memory impairment induced by global cerebral ischemia/reperfusion in gerbils via attenuating the phosphorylation level of CaMKII and further preventing hippocampal neuronal apoptosis. PMID:27016057

  20. Trichuris spp. (Nematoda: Trichuridae) from two rodents, Mastomys natalensis and Gerbilliscus vicinus in Tanzania.

    PubMed

    Ribas, Alexis; López, Sergi; Makundi, Rhodes H; Leirs, Herwig; de Bellocq, Joëlle Goüy

    2013-10-01

    During a survey of the helminth community of several rodent species in the Morogoro region (Tanzania), Trichuris whipworms (Nematoda: Trichuridae) were found in the ceca of the Natal multimammate mouse, Mastomys natalensis and a gerbil, Gerbilliscus vicinus (both Rodentia: Muridae). The taxonomic literature regarding Trichuris from African native rodents describes 10 species, but includes few metric and morphologic characters that discriminate between some of the pairs. The whipworms we sampled in Tanzanian Natal multimammate mice and gerbils were morphologically identified, respectively, as Trichuris mastomysi Verster, 1960 and Trichuris carlieri Gedoelst, 1916 sensu lato, but with characters that overlap or partially overlap with the cosmopolitan Murinae whipworm, Trichuris muris , already reported from several rodents in Africa. To clarify our identification, we sequenced the ITS-1, 5.8S, and ITS-2 ribosomal DNA region of the worms' nuclear genome. The genetic analyses clearly distinguish the whipworms we found in M. natalensis from those found in the gerbil, and both of these from T. muris whipworm reference sequences. The overlap of morphological characters between rodent whipworms suggests that reports of T. muris from rodent species not closely related to Murinae in other parts of Africa should be treated with caution. PMID:23560615

  1. Noise-gated encoding of slow inputs by auditory brain stem neurons with a low-threshold K+ current.

    PubMed

    Gai, Yan; Doiron, Brent; Kotak, Vibhakar; Rinzel, John

    2009-12-01

    Phasic neurons, which do not fire repetitively to steady depolarization, are found at various stages of the auditory system. Phasic neurons are commonly described as band-pass filters because they do not respond to low-frequency inputs even when the amplitude is large. However, we show that phasic neurons can encode low-frequency inputs when noise is present. With a low-threshold potassium current (I(KLT)), a phasic neuron model responds to rising and falling phases of a subthreshold low-frequency signal with white noise. When the white noise was low-pass filtered, the phasic model also responded to the signal's trough but still not to the peak. In contrast, a tonic neuron model fired mostly to the signal's peak. To test the model predictions, whole cell slice recordings were obtained in the medial (MSO) and lateral (LSO) superior olivary neurons in gerbil from postnatal day 10 (P10) to 22. The phasic MSO neurons with strong I(KLT), mostly from gerbils aged P17 or older, showed firing patterns consistent with the preceding predictions. Moreover, injecting a virtual I(KLT) into weak-phasic MSO and tonic LSO neurons with putative weak or no I(KLT) (from gerbils younger than P17) shifted the neural response from the signal's peak to the rising phase. These findings advance our knowledge about how noise gates the signal pathway and how phasic neurons encode slow envelopes of sounds with high-frequency carriers. PMID:19812289

  2. Cyclic transmission of Sarcocystis gerbilliechis n. sp. by the Arabian saw-scaled viper, Echis coloratus, to rodents of the subfamily gerbillinae.

    PubMed

    Jäkel, T

    1995-08-01

    Infection experiments with rodents and snakes were performed to elucidate the life cycle of a Sarcocystis isolate found in an Arabian saw-scaled viper, Echis coloratus. Oocytes in feces of the naturally infected and of 2 experimentally infected Arabian saw-scaled vipers were already sporulated and contained 2 sporocysts each, measuring 12.7 (12.3-13.3) microns x 11.0 (10.7-11.4) microns. After oral inoculation of various rodent species with these sporocysts, sarcocysts developed in the esophagus and skeletal muscles of gerbils and related genera. Mature sarcocysts were filiform in shape and reached a maximum length of 11.7 mm after 5 mo postinoculation (PI), whereas the width did not exceed 190 microns. The primary cyst wall formed small, knoblike protrusions, which were up to 180 nm long and 120 nm wide. Mature schizonts were present in the liver and other organs of gerbils between 11 and 14 days PI. After inoculation of vipers of 3 different genera with mature sarcocysts from gerbils, oocysts developed in the intestine of Arabian saw-scaled vipers. A comparison of these data with those from previously described Sarcocystis species with snake-rodent life cycles suggests that Sarcocystis gerbilliechis is a new species. PMID:7623207

  3. Quantification of Central Substance P Receptor Occupancy by Aprepitant Using Small Animal Positron Emission Tomography

    PubMed Central

    Endo, Tadashi; Saijo, Takeaki; Haneda, Eisuke; Maeda, Jun; Tokunaga, Masaki; Zhang, Ming-Rong; Kannami, Ayako; Asai, Hidetoshi; Suzuki, Masayuki; Suhara, Tetsuya

    2015-01-01

    Background: Central substance P receptors, termed NK-1 receptors, have been considered as therapeutic targets in the development of drugs against diverse conditions, including emesis, overactive bladder, and depression. Methods: Here, we applied small animal positron emission tomography (PET) and a radioligand for NK-1 receptors ([18F]FE-SPA-RQ) for measuring occupancies of these receptors by a selective antagonist (aprepitant) in order to examine the validity of this in vivo imaging system for preclinical characterization of candidate agents acting on NK-1 receptors, and as a tool for predicting optimal doses in humans. Results: PET in gerbils depicted high uptake in the striatum and dose-dependent displacement with increasing doses of aprepitant. Occupancies increased as a function of aprepitant plasma concentrations according to a one-site competition model, which agrees with reported occupancy-concentration relationships in clinical studies after correction for species differences in plasma protein-unbound aprepitant fractions. These occupancy data were further supported by ex vivo autoradiography of brain samples from aprepitant-treated gerbils. In a pilot study of a marmoset, we obtained more accurate determinations of NK-1 receptor occupancy, less affected by spillover of signals from extracranial tissues than in gerbil experiments. Conclusions: These findings support the utility of small animals and quantitative PET in the development of drugs targeting NK-1 receptors. PMID:25609595

  4. [Brucellosis, tularemia and borreliosis isolated from wild animals captured in Ankara, Konya, Urfa and Nevsehir provinces in Turkey].

    PubMed

    Ozsan, K; Fazh, A; Aktan, M; Beyoğlu, K

    1976-10-01

    621 citellus, 41 Mus musculus, 35 microtus, 442 meriones, 70 Rattus rattus, 56 turtle, 89 hare, 1 hamster, 1 hedgehog and 1 sea snake, altogether 1379 wild animals were captured in Ankara, Konya, Urfa and Nevşehir. Neither Brucella or Francisella tularansis could be isolated nor borrelia could be seen. 1/40-1/80 agglutination titers obtained in 3 out of 134 sera taken from citellus, in 3 out of 264 sera taken from guinea pigs which were inoculated with spleen, liver and kidney suspensions of wild animals. 1/40-1/80 agglutination titers obtained against brucella antigen in 3 out of 125 sera taken from citellus. No significant agglutination titers could be obtained in 35 sera taken from guinea pigs which were inoculated with the organ suspensions of wild animals. In blood samples of 2 citellus few trypanosoma were detected. PMID:979704

  5. [Studies of Yersinia pestis in wild animals captured in Ankara, Konya and Nevsehir].

    PubMed

    Ozsan, K; Fazli, A; Aktan, M; Beyoğlu, K

    1976-01-01

    No Yersinia pestis could be isolated, by culturing and by inoculations to 1212 guinea-pigs and 150 mice; from 623 citellus, 41 Mus musculus, 55 Microtus, 442 Meriones, 70 Rattus rattus, 56 turtle, 89 hare, 1 hamster, 1 hedgehog, 1 sea snake, altogether 790 dead, 589 alive, i.e. 1379. wild animals captured in Ankara, Konya (Karapinar), Urfa (Akçakale) and in Nevşehir. In 141 sera taken from citellus captured alive, and in 174 sera taken from guinea-pigs inoculated with spleen, liver and kidney suspensions of wild animals, 1/20 - 1/80 agglutination titers (one of the sera from a guinea-pig inoculated with hare organ suspension) were obtained. These findings, probably were due to Yersinia pseudotuberculosis, because this organism was isolated from citellus captured in Ankara and Konya. PMID:933892

  6. The comparative gastrointestinal morphology of five species of muroid rodents found in Saudi Arabia.

    PubMed

    Walters, Jacklynn; Marais, Sumine; Johnson, Olga; Bennett, Nigel C; Alagaili, Abdulaziz N; Mohammed, Osama B; Kotzé, Sanet H

    2014-09-01

    Meriones rex (King jird), Meriones libycus (Libyan jird), Acomys dimidiatus (Eastern spiny mouse), Acomys cahirinus (Egyptian spiny mouse), and Dipodillus dasyurus (Wagner's dipodil) are five species of small rodents of the superfamily Muroidea with distributions in Eastern Africa, Egypt, and the desert regions of the Arabian Peninsula. Water is scarce in these regions and may result in relatively low-digestible food. The aim of the present study is to describe and compare the gastrointestinal tract morphology and morphometry of these five species in order to elucidate whether morphology is influenced by phylogeny or dietary preference. Each segment of the gastrointestinal tract of each species was macroscopically examined and the length and basal surface area of each segment was measured. Standard histologic procedures were performed to determine a surface enlargement factor to determine the mucosal luminal surface area. A unilocular-hemiglandular stomach was observed in all the species examined. The caeca of all the species were long and arranged into a loose spiral toward the caecal tip with the ileocaecal and caeco-colic openings positioned close together. Two rows of oblique folds could be observed in the proximal colon of all species except in D. dasyurus which had longitudinal folds. Morphometric analysis showed the largest stomach in A. cahirinus and the largest caecum and colon in M. libycus. All the species can be grouped in the family Muridae in two subfamilies and similarities were observed including the hemiglandular stomach and relatively large caecum. It could be concluded that phylogeny plays an important role in determining gastrointestinal morphology while diet plays a subordinate role in the desert rodents in the present study. PMID:24664865

  7. Host cell killing by the West Nile Virus NS2B-NS3 proteolytic complex: NS3 alone is sufficient to recruit caspase-8-based apoptotic pathway

    SciTech Connect

    Ramanathan, Mathura P.; Chambers, Jerome A.; Pankhong, Panyupa; Chattergoon, Michael; Attatippaholkun, Watcharee; Dang, Kesen; Shah, Neelima; Weiner, David B. . E-mail: dbweiner@mail.med.upenn.edu

    2006-02-05

    The West Nile Virus (WNV) non-structural proteins 2B and 3 (NS2B-NS3) constitute the proteolytic complex that mediates the cleavage and processing of the viral polyprotein. NS3 recruits NS2B and NS5 proteins to direct protease and replication activities. In an effort to investigate the biology of the viral protease, we cloned cDNA encoding the NS2B-NS3 proteolytic complex from brain tissue of a WNV-infected dead crow, collected from the Lower Merion area (Merion strain). Expression of the NS2B-NS3 gene cassette induced apoptosis within 48 h of transfection. Electron microscopic analysis of NS2B-NS3-transfected cells revealed ultra-structural changes that are typical of apoptotic cells including membrane blebbing, nuclear disintegration and cytoplasmic vacuolations. The role of NS3 or NS2B in contributing to host cell apoptosis was examined. NS3 alone triggers the apoptotic pathways involving caspases-8 and -3. Experimental results from the use of caspase-specific inhibitors and caspase-8 siRNA demonstrated that the activation of caspase-8 was essential to initiate apoptotic signaling in NS3-expressing cells. Downstream of caspase-3 activation, we observed nuclear membrane ruptures and cleavage of the DNA-repair enzyme, PARP in NS3-expressing cells. Nuclear herniations due to NS3 expression were absent in the cells treated with a caspase-3 inhibitor. Expression of protease and helicase domains themselves was sufficient to trigger apoptosis generating insight into the apoptotic pathways triggered by NS3 from WNV.

  8. Mapping the distribution of the main host for plague in a complex landscape in Kazakhstan: An object-based approach using SPOT-5 XS, Landsat 7 ETM+, SRTM and multiple Random Forests.

    PubMed

    Wilschut, L I; Addink, E A; Heesterbeek, J A P; Dubyanskiy, V M; Davis, S A; Laudisoit, A; M Begon; Burdelov, L A; Atshabar, B B; de Jong, S M

    2013-08-01

    Plague is a zoonotic infectious disease present in great gerbil populations in Kazakhstan. Infectious disease dynamics are influenced by the spatial distribution of the carriers (hosts) of the disease. The great gerbil, the main host in our study area, lives in burrows, which can be recognized on high resolution satellite imagery. In this study, using earth observation data at various spatial scales, we map the spatial distribution of burrows in a semi-desert landscape. The study area consists of various landscape types. To evaluate whether identification of burrows by classification is possible in these landscape types, the study area was subdivided into eight landscape units, on the basis of Landsat 7 ETM+ derived Tasselled Cap Greenness and Brightness, and SRTM derived standard deviation in elevation. In the field, 904 burrows were mapped. Using two segmented 2.5 m resolution SPOT-5 XS satellite scenes, reference object sets were created. Random Forests were built for both SPOT scenes and used to classify the images. Additionally, a stratified classification was carried out, by building separate Random Forests per landscape unit. Burrows were successfully classified in all landscape units. In the 'steppe on floodplain' areas, classification worked best: producer's and user's accuracy in those areas reached 88% and 100%, respectively. In the 'floodplain' areas with a more heterogeneous vegetation cover, classification worked least well; there, accuracies were 86 and 58% respectively. Stratified classification improved the results in all landscape units where comparison was possible (four), increasing kappa coefficients by 13, 10, 9 and 1%, respectively. In this study, an innovative stratification method using high- and medium resolution imagery was applied in order to map host distribution on a large spatial scale. The burrow maps we developed will help to detect changes in the distribution of great gerbil populations and, moreover, serve as a unique empirical

  9. Neurovestibular Compensation following Ototoxic Lesion and Labyrinthectomy.

    PubMed

    Yazdanshenas, Hamed; Ashouri, Anousheh; Kaufman, Galen

    2016-04-01

    Introduction Unilateral labyrinthectomy and intra-tympanic gentamycin have been employed in the treatment of Ménière's disease, but the efficacy of these techniques has not been well established. Objective The objective of this study is to measure the time course of recovery from a unilateral labyrinthectomy either after ipsilateral topical treatment with gentamicin to the inner ear or without the previous insult. Methods Twenty-nine adult Mongolian gerbils were randomized into two experimental groups. Group 1 (n = 17) received a right ear gentamicin drug-induced lesion by unilateral labyrinthectomy (UL). Group 2 (n = 12) only received a right unilateral labyrinthectomy lesion. We measured the horizontal vestibulo-ocular responses in gerbils before and after the lesion. The gerbils received an angular acceleration stimulus and their eye movements were recorded. Results The gentamicin lesion resulted in a quicker recovery. Experimental groups underwent a similar time course of recovery. Statistical analysis showed no significant difference between the two groups. Both groups displayed adaptation to the lesion by day 21, but long-term compensation did not completely revert to the original pre-lesion state. Conclusions In a lesion requiring both static and dynamic compensation as in UL, the need for a static compensation may alter pre-existing compensation from a previous dynamic insult and require a new compensation. A previous lesion and adaptation is not preserved for a second lesion and the subject has to re-compensate. Therefore, surgical treatment in Meniere's disease such as UL can be considered without prior gentamicin treatment. Static and dynamic compensations do not appear to be as independent as previous studies have suggested. PMID:27096015

  10. From Zebrafish to Mammal: Functional Evolution of Prestin, the Motor Protein of Cochlear Outer Hair Cells

    PubMed Central

    Tan, Xiaodong; Pecka, Jason L.; Tang, Jie; Okoruwa, Oseremen E.; Zhang, Qian

    2011-01-01

    Prestin is the motor protein of cochlear outer hair cells. It belongs to a distinct anion transporter family called solute carrier protein 26A, or SLC26A. Members of this family serve two fundamentally distinct functions. Although most members transport different anion substrates across a variety of epithelia, prestin (SLC26A5) is unique, functioning as a voltage-dependent motor protein. Recent evidence suggests that prestin orthologs from zebrafish and chicken are electrogenic divalent/chloride anion exchangers/transporters with no motor function. These studies appear to suggest that prestin was evolved from an anion transporter. We examined the motor and transport functions of prestin and its orthologs from four different species in the vertebrate lineage, to gain insights of how these two physiological functions became distinct. Somatic motility, voltage-dependent nonlinear capacitance (NLC), and transporter function were measured in transfected human embryonic kidney (HEK) cells using voltage-clamp and anion uptake techniques. Zebrafish and chicken prestins both exhibited weak NLC, with peaks significantly shifted in the depolarization (right) direction. This was contrasted by robust NLC with peaks left shifted in the platypus and gerbil. The platypus and gerbil prestins retained little transporter function compared with robust anion transport capacities in the zebrafish and chicken orthologs. Somatic motility was detected only in the platypus and gerbil prestins. There appears to be an inverse relationship between NLC and anion transport functions, whereas motor function appears to have emerged only in mammalian prestin. Our results suggest that motor function is an innovation of therian prestin and is concurrent with diminished transporter capabilities. PMID:21047933

  11. First isolation of Hammondia heydorni from dogs in China.

    PubMed

    Jie, Hu Jun; Yu, Meng; Fen, Yang Yan; Mei, Guo Yan; Yan, Yang; Esch, G W; QingTuan, Fu

    2013-10-18

    Fecal samples of 945 dogs were examined microscopically in 2 refuge facilities in China from March 2010 to November 2011. In 8 dogs, oocysts, 9-14 μm in size, were found. Their morphology was similar to those of Hammondia heydorni and Neospora caninum. Sporulated Hammondia/Neospora-like oocysts were fed to 2 dogs, 2 gerbils, 2 guinea pigs, and 2 KM mice; tissues from these inoculated animals were then fed to coccidia-free dogs to determine species susceptibility to these oocysts. Oocysts were not excreted in the feces of dogs or rodents inoculated with oocysts. However, the dogs fed the tissues of gerbils or guinea pigs that were inoculated orally with oocysts excreted fresh oocysts. Dogs fed tissues from guinea pigs inoculated with brain and muscular homogenate from guinea pigs that were fed sporulated Hammondia/Neospora-like oocysts did not excrete oocysts. These findings indicated that the oocysts from naturally infected dogs had an obligatory 2-host life cycle, with gerbils and guinea pigs as intermediate hosts. DNA isolated from these oocysts could not be amplified using N. caninum- and Toxoplasma gondii-specific primers. However, positive amplification with the H. heydorni-specific primers confirmed the presence of H. heydorni DNA in the samples. A comparison of the intron 1 sequence of the alpha tubulin gene with those from H. heydorni from dogs and H. triffittae from foxes showed that dog-derived oocysts possessed a different alpha tubulin gene. Both our dog-derived sequence and 2 previous alpha tubulin gene sequences from H. triffittae from foxes contained a 9-bp insertion relative to 3 sequences of H. heydorni from dogs. However, when the 9-bp insertion from H. triffittae sequences were compared, the 9-bp insertion in our dog-derived sequence had a nucleotide substitution. The present study, therefore, provides new evidence of genetic diversity among isolates from dogs. This is the first survey for H. heydorni in dogs from China. PMID:23731857

  12. Hydrogen Metabolism in Helicobacter pylori Plays a Role in Gastric Carcinogenesis through Facilitating CagA Translocation

    PubMed Central

    Wang, Ge; Romero-Gallo, Judith; Benoit, Stéphane L.; Piazuelo, M. Blanca; Dominguez, Ricardo L.; Morgan, Douglas R.; Peek, Richard M.

    2016-01-01

    ABSTRACT A known virulence factor of Helicobacter pylori that augments gastric cancer risk is the CagA cytotoxin. A carcinogenic derivative strain, 7.13, that has a greater ability to translocate CagA exhibits much higher hydrogenase activity than its parent noncarcinogenic strain, B128. A Δhyd mutant strain with deletion of hydrogenase genes was ineffective in CagA translocation into human gastric epithelial AGS cells, while no significant attenuation of cell adhesion was observed. The quinone reductase inhibitor 2-n-heptyl-4-hydroxyquinoline-N-oxide (HQNO) was used to specifically inhibit the H2-utilizing respiratory chain of outer membrane-permeabilized bacterial cells; that level of inhibitor also greatly attenuated CagA translocation into AGS cells, indicating the H2-generated transmembrane potential is a contributor to toxin translocation. The Δhyd strain showed a decreased frequency of DNA transformation, suggesting that H. pylori hydrogenase is also involved in energizing the DNA uptake apparatus. In a gerbil model of infection, the ability of the Δhyd strain to induce inflammation was significantly attenuated (at 12 weeks postinoculation), while all of the gerbils infected with the parent strain (7.13) exhibited a high level of inflammation. Gastric cancer developed in 50% of gerbils infected with the wild-type strain 7.13 but in none of the animals infected with the Δhyd strain. By examining the hydrogenase activities from well-defined clinical H. pylori isolates, we observed that strains isolated from cancer patients (n = 6) have a significantly higher hydrogenase (H2/O2) activity than the strains isolated from gastritis patients (n = 6), further supporting an association between H. pylori hydrogenase activity and gastric carcinogenesis in humans. PMID:27531909

  13. From zebrafish to mammal: functional evolution of prestin, the motor protein of cochlear outer hair cells.

    PubMed

    Tan, Xiaodong; Pecka, Jason L; Tang, Jie; Okoruwa, Oseremen E; Zhang, Qian; Beisel, Kirk W; He, David Z Z

    2011-01-01

    Prestin is the motor protein of cochlear outer hair cells. It belongs to a distinct anion transporter family called solute carrier protein 26A, or SLC26A. Members of this family serve two fundamentally distinct functions. Although most members transport different anion substrates across a variety of epithelia, prestin (SLC26A5) is unique, functioning as a voltage-dependent motor protein. Recent evidence suggests that prestin orthologs from zebrafish and chicken are electrogenic divalent/chloride anion exchangers/transporters with no motor function. These studies appear to suggest that prestin was evolved from an anion transporter. We examined the motor and transport functions of prestin and its orthologs from four different species in the vertebrate lineage, to gain insights of how these two physiological functions became distinct. Somatic motility, voltage-dependent nonlinear capacitance (NLC), and transporter function were measured in transfected human embryonic kidney (HEK) cells using voltage-clamp and anion uptake techniques. Zebrafish and chicken prestins both exhibited weak NLC, with peaks significantly shifted in the depolarization (right) direction. This was contrasted by robust NLC with peaks left shifted in the platypus and gerbil. The platypus and gerbil prestins retained little transporter function compared with robust anion transport capacities in the zebrafish and chicken orthologs. Somatic motility was detected only in the platypus and gerbil prestins. There appears to be an inverse relationship between NLC and anion transport functions, whereas motor function appears to have emerged only in mammalian prestin. Our results suggest that motor function is an innovation of therian prestin and is concurrent with diminished transporter capabilities. PMID:21047933

  14. Aerobic Exercise Alleviates Ischemia-Induced Memory Impairment by Enhancing Cell Proliferation and Suppressing Neuronal Apoptosis in Hippocampus

    PubMed Central

    Seo, Tae-Beom; Kim, Tae-Woon; Shin, Mal-Soon; Ji, Eun-Sang; Cho, Han-Sam; Lee, Jae-Min; Kim, Tae-Wook

    2014-01-01

    Purpose Neurogenic lower urinary tract dysfunction (NLUTD) is a possible consequence of several neurological disorders. NLUTD may produce debilitating symptoms and serious complications, such as chronic renal failure, and recurrent urinary tract infections. Many animal studies of NLUTD symptoms have focused on animal models of cerebral ischemia. In the present study, we investigated the effects of treadmill exercise on memory function and its relation to cell proliferation and apoptosis in the hippocampus, following transient global ischemia in gerbils. Methods To induce transient global ischemia in gerbil, both common carotid arteries were occluded for 5 minutes. Gerbils in the exercise groups were forced to run on a treadmill exercise for 30 minutes once a day for 2 weeks. Step-down avoidance task and Y maze task were performed. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-staining, immunohistochemistry for 5-bromo-2'-deoxyridine, doublecortin, caspase-3, and Western blot for brain-derived neurotrophic factor (BDNF), Bax, Bcl-2, cytochrome c, caspase-3 were conducted. Results Ischemia caused memory impairment with an increase of cell proliferation, BDNF expression, and apoptosis in the hippocampus. Treadmill exercise improved memory function with further increase of cell proliferation and BDNF expression and a decrease of apoptosis. Conclusions The animal model that we have developed and our assessment of the relation between exercise and brain function can be useful tools for future investigations of NLUTD symptoms associated with stroke, particularly ischemic stroke. The present study suggests that treadmill exercise promoted the recovery of brain function after cerebral ischemia. PMID:25562035

  15. The trophic responses of two different rodent–vector–plague systems to climate change

    PubMed Central

    Xu, Lei; Schmid, Boris V.; Liu, Jun; Si, Xiaoyan; Stenseth, Nils Chr.; Zhang, Zhibin

    2015-01-01

    Plague, the causative agent of three devastating pandemics in history, is currently a re-emerging disease, probably due to climate change and other anthropogenic changes. Without understanding the response of plague systems to anthropogenic or climate changes in their trophic web, it is unfeasible to effectively predict years with high risks of plague outbreak, hampering our ability for effective prevention and control of the disease. Here, by using surveillance data, we apply structural equation modelling to reveal the drivers of plague prevalence in two very different rodent systems: those of the solitary Daurian ground squirrel and the social Mongolian gerbil. We show that plague prevalence in the Daurian ground squirrel is not detectably related to its trophic web, and that therefore surveillance efforts should focus on detecting plague directly in this ecosystem. On the other hand, plague in the Mongolian gerbil is strongly embedded in a complex, yet understandable trophic web of climate, vegetation, and rodent and flea densities, making the ecosystem suitable for more sophisticated low-cost surveillance practices, such as remote sensing. As for the trophic webs of the two rodent species, we find that increased vegetation is positively associated with higher temperatures and precipitation for both ecosystems. We furthermore find a positive association between vegetation and ground squirrel density, yet a negative association between vegetation and gerbil density. Our study thus shows how past surveillance records can be used to design and improve existing plague prevention and control measures, by tailoring them to individual plague foci. Such measures are indeed highly needed under present conditions with prevailing climate change. PMID:25540277

  16. Mapping the distribution of the main host for plague in a complex landscape in Kazakhstan: An object-based approach using SPOT-5 XS, Landsat 7 ETM+, SRTM and multiple Random Forests

    NASA Astrophysics Data System (ADS)

    Wilschut, L. I.; Addink, E. A.; Heesterbeek, J. A. P.; Dubyanskiy, V. M.; Davis, S. A.; Laudisoit, A.; Begon, M.; Burdelov, L. A.; Atshabar, B. B.; de Jong, S. M.

    2013-08-01

    Plague is a zoonotic infectious disease present in great gerbil populations in Kazakhstan. Infectious disease dynamics are influenced by the spatial distribution of the carriers (hosts) of the disease. The great gerbil, the main host in our study area, lives in burrows, which can be recognized on high resolution satellite imagery. In this study, using earth observation data at various spatial scales, we map the spatial distribution of burrows in a semi-desert landscape. The study area consists of various landscape types. To evaluate whether identification of burrows by classification is possible in these landscape types, the study area was subdivided into eight landscape units, on the basis of Landsat 7 ETM+ derived Tasselled Cap Greenness and Brightness, and SRTM derived standard deviation in elevation. In the field, 904 burrows were mapped. Using two segmented 2.5 m resolution SPOT-5 XS satellite scenes, reference object sets were created. Random Forests were built for both SPOT scenes and used to classify the images. Additionally, a stratified classification was carried out, by building separate Random Forests per landscape unit. Burrows were successfully classified in all landscape units. In the ‘steppe on floodplain’ areas, classification worked best: producer's and user's accuracy in those areas reached 88% and 100%, respectively. In the ‘floodplain’ areas with a more heterogeneous vegetation cover, classification worked least well; there, accuracies were 86 and 58% respectively. Stratified classification improved the results in all landscape units where comparison was possible (four), increasing kappa coefficients by 13, 10, 9 and 1%, respectively. In this study, an innovative stratification method using high- and medium resolution imagery was applied in order to map host distribution on a large spatial scale. The burrow maps we developed will help to detect changes in the distribution of great gerbil populations and, moreover, serve as a unique

  17. Inhibitory Effects of Isoquinoline Alkaloid Berberine on Ischemia-Induced Apoptosis via Activation of Phosphoinositide 3-Kinase/Protein Kinase B Signaling Pathway

    PubMed Central

    Kim, Mia; Shin, Mal Soon; Lee, Jae Min; Cho, Han Sam; Kim, Chang Ju; Kim, Young Joon; Choi, Hey Ran

    2014-01-01

    Purpose Berberine is a type of isoquinoline alkaloid that has been used to treat various diseases. A neuroprotective effect of berberine against cerebral ischemia has been reported; however, the effects of berberine on apoptosis in relation to reactive astrogliosis and microglia activation under ischemic conditions have not yet been fully evaluated. In the present study, we investigated the effects of berberine on global ischemia-induced apoptosis, and focused on the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway in the hippocampus using gerbils. Methods Gerbils received berberine orally once a day for 14 consecutive days, starting one day after surgery. In this study, a step-down avoidance task was used to assess short-term memory. Furthermore, we employed the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay to evaluate DNA fragmentation, immunohistochemistry to investigate glial fibriallary acidic protein, CD11b, and caspase-3, and western blot to assess PI3K, Akt, Bax, Bcl-2, and cytochrome c. Results Our results revealed that berberine treatment alleviated ischemia-induced short-term memory impairment. Treatment with berbeine also attenuated ischemia-induced apoptosis and inhibited reactive astrogliosis and microglia activation. Furthermore, berberine enhanced phospho-PI3K and phospho-Akt expression in the hippocampus of ischemic gerbils. Conclusions Berberine exerted a neuroprotective effect against ischemic insult by inhibiting neuronal apoptosis via activation of the PI3K/Akt signaling pathway. The antiapoptotic effect of berberine was achieved through inhibition of reactive astrogliosis and microglia activation. Berberine may therefore serve as a therapeutic agent for stroke-induced neurourological problems. PMID:25279238

  18. Comparison of the phenotype of NK1R-/- mice with pharmacological blockade of the substance P (NK1 ) receptor in assays for antidepressant and anxiolytic drugs.

    PubMed

    Rupniak, N M; Carlson, E J; Webb, J K; Harrison, T; Porsolt, R D; Roux, S; de Felipe, C; Hunt, S P; Oates, B; Wheeldon, A

    2001-11-01

    The phenotype of NK1R-/- mice was compared with that of acute pharmacological blockade of the tachykinin NK1 receptor on sensorimotor function and in assays relevant to depressive illness and anxiety. The dose range for L-760735 and GR205171 that was associated with functional blockade of central NK1 receptors in the target species was established by antagonism of the behavioural effects of intracerebroventricular NK1 agonist challenge in gerbils, mice and rats. The caudal grooming and scratching response to GR73632 was absent in NK1R-/- mice, confirming that the receptor had been genetically ablated. There was no evidence of sedation or motor impairment in NK1R-/- mice or following administration of L-760735 to gerbils, even at doses in excess of those required for central NK1 receptor occupancy. In the resident-intruder and forced swim test, the behaviour of NK1R-/- mice, or animals treated acutely with L-760735 or GR205171, resembled that seen with the clinically used antidepressant drug fluoxetine. However, the effects of GR205171 were not clearly enantioselective in mice. In contrast, although NK1R-/- mice also exhibited an increase in the duration of struggle behaviour in the tail suspension test, this was not observed following pharmacological blockade with L-760735 in gerbils or GR205171 in mice, suggesting that this may reflect a developmental alteration in the knockout mouse. There was no effect of NK1 receptor blockade with L-760735 in guinea-pigs or GR205171 in rats, or deletion of the NK1 receptor in mice, on behaviour in the elevated plus-maze test for anxiolytic activity. These findings extend previous observations on the phenotype of the NK1R-/- mouse and establish a broadly similar profile following acute pharmacological blockade of the receptor. These studies also serve to underscore the limitations of currently available antagonists that are suitable for use in rat and mouse behavioural assays. PMID:11742144

  19. Neurovestibular Compensation following Ototoxic Lesion and Labyrinthectomy

    PubMed Central

    Yazdanshenas, Hamed; Ashouri, Anousheh; Kaufman, Galen

    2016-01-01

    Introduction Unilateral labyrinthectomy and intra-tympanic gentamycin have been employed in the treatment of Ménière's disease, but the efficacy of these techniques has not been well established. Objective The objective of this study is to measure the time course of recovery from a unilateral labyrinthectomy either after ipsilateral topical treatment with gentamicin to the inner ear or without the previous insult. Methods Twenty-nine adult Mongolian gerbils were randomized into two experimental groups. Group 1 (n = 17) received a right ear gentamicin drug-induced lesion by unilateral labyrinthectomy (UL). Group 2 (n = 12) only received a right unilateral labyrinthectomy lesion. We measured the horizontal vestibulo-ocular responses in gerbils before and after the lesion. The gerbils received an angular acceleration stimulus and their eye movements were recorded. Results The gentamicin lesion resulted in a quicker recovery. Experimental groups underwent a similar time course of recovery. Statistical analysis showed no significant difference between the two groups. Both groups displayed adaptation to the lesion by day 21, but long-term compensation did not completely revert to the original pre-lesion state. Conclusions In a lesion requiring both static and dynamic compensation as in UL, the need for a static compensation may alter pre-existing compensation from a previous dynamic insult and require a new compensation. A previous lesion and adaptation is not preserved for a second lesion and the subject has to re-compensate. Therefore, surgical treatment in Meniere's disease such as UL can be considered without prior gentamicin treatment. Static and dynamic compensations do not appear to be as independent as previous studies have suggested. PMID:27096015

  20. Binding of radiolabeled misonidazole in cerebral infarction

    SciTech Connect

    Rasey, J.S.; Hoffman, J.; Spence, A.M.; Krohn, K.A.

    1985-05-01

    The metabolic trapping of the radiolabeled nitroimidazole, misonidazole, in viable hypoxic tissue may form the basis for the nuclear imaging of ischemia in cerebral infarction. Misonidazole congeners could be labeled with /sup 75/Br, /sup 18/F, or /sup 11/C and detected with PET. Infarction was induced in male Mongolian gerbils by ligation of the right common carotid artery. Severity of the lesions was determined by scoring neurological symptoms with a stroke index, in which scores >10, out of a possible 25, indicate presence of a severe infarct. Gerbils with scores ranging from 0 (asymptomatic) to 13 as well as control (unligated) animals received 3 injections (50 ..mu..Moles/kg) of /sup 3/H-misonidazole in 2 hours and % injected dose/g (% I.D./g) was determined 2 hours after the final injection. Uptake into whole brain of control animals averaged 0.137 +- 0.0168 % I.D./g. The cerebral hemispheres of ligated gerbils were divided into 7, 2 mm-thick coronal sections which were then bisected. In the right half of slide number3 (midparietal region) the % I.D./g increased with increasing stroke index. For animals with a stroke index = 0, uptake was 0.159 % I.D./g, and right/left R/L ratio was 1.07. For 2 animals with a score = 13, uptake in the same region ws 0.752 and 0.717 and I.D./g with R/L ratios of 3.29 and 2.3l, respectively. Animals with intermediate scores had moderately elevated uptake. The authors conclude that the uptake of /sup 3/H-misonidazole in the right hemisphere positively correlates with the severity of infarction. Studies are underway to determine whether the regions of highest uptake correlate with histological evidence of infarction and reduced oxygen availability.

  1. The acetylcholine fiber density of the neocortex is altered by isolated rearing and early methamphetamine intoxication in rodents.

    PubMed

    Lehmann, Konrad; Hundsdörfer, Benjamin; Hartmann, Thorsten; Teuchert-Noodt, Gertraud

    2004-09-01

    Alterations in the cholinergic physiology of the brain were the first to be observed when research on environmental influences on postnatal brain development began 35 years ago. Since then, the effects of isolated rearing (IR) or early pharmacological insults have been shown not only on the physiology, but also the anatomy of a variety of transmitter systems. The cholinergic fiber density, however, still remained to be assessed. We therefore used a histochemical procedure to stain cholinergic fibers in the brains of young adult gerbils reared either in groups in enriched environments or isolated in standard makrolon cages. Half of the animals from each rearing condition had received a single high dose of methamphetamine on postnatal day 14. Fiber densities were measured by computerized image analysis in the medial and orbital prefrontal cortex (PFC), dysgranular and granular insular cortex, sensorimotor cortices, and the entorhinal cortex of both hemispheres. Isolation rearing increased the cholinergic fiber densities in the prefrontal cortices of the left hemisphere and in the entorhinal cortex of the right hemisphere by about 10%, with no effect in the respective contralateral side. The early methamphetamine intoxication showed no influence in prefrontal and entorhinal cortices, but diminished the acetylcholine (ACh) innervation of the forelimb area of cortex in both hemispheres in IR gerbils and of the left hemisphere in ER gerbils, and reduced the acetylcholine innervation in the hindlimb area in both sides in both rearing groups. These results demonstrate that (a) cholinergic fiber density is differentially regulated in different cortical areas and (b) the plasticity of the cholinergic system can only be understood in the interplay with other neuromodulatory innervations. PMID:15296843

  2. The trophic responses of two different rodent-vector-plague systems to climate change.

    PubMed

    Xu, Lei; Schmid, Boris V; Liu, Jun; Si, Xiaoyan; Stenseth, Nils Chr; Zhang, Zhibin

    2015-02-01

    Plague, the causative agent of three devastating pandemics in history, is currently a re-emerging disease, probably due to climate change and other anthropogenic changes. Without understanding the response of plague systems to anthropogenic or climate changes in their trophic web, it is unfeasible to effectively predict years with high risks of plague outbreak, hampering our ability for effective prevention and control of the disease. Here, by using surveillance data, we apply structural equation modelling to reveal the drivers of plague prevalence in two very different rodent systems: those of the solitary Daurian ground squirrel and the social Mongolian gerbil. We show that plague prevalence in the Daurian ground squirrel is not detectably related to its trophic web, and that therefore surveillance efforts should focus on detecting plague directly in this ecosystem. On the other hand, plague in the Mongolian gerbil is strongly embedded in a complex, yet understandable trophic web of climate, vegetation, and rodent and flea densities, making the ecosystem suitable for more sophisticated low-cost surveillance practices, such as remote sensing. As for the trophic webs of the two rodent species, we find that increased vegetation is positively associated with higher temperatures and precipitation for both ecosystems. We furthermore find a positive association between vegetation and ground squirrel density, yet a negative association between vegetation and gerbil density. Our study thus shows how past surveillance records can be used to design and improve existing plague prevention and control measures, by tailoring them to individual plague foci. Such measures are indeed highly needed under present conditions with prevailing climate change. PMID:25540277

  3. Use of Neonatal Fostering To Remove Helicobacter spp. from Deer Mice (Peromyscus maniculatus)

    PubMed Central

    Pritchett-Corning, Kathleen R; Peery, Harry E; Crossland, Janet P; Wyatt, Heather M; Stuart, Marilyne; Mothersill, Carmel E

    2015-01-01

    Helicobacter species can be found in a wide variety of animals and remain common contaminants of laboratory rodents. Fostering of neonatal pups has been used to eliminate Helicobacter spp. from various laboratory rodents, including laboratory mice and gerbils. Deer mice (Peromyscus maniculatus) from a captive colony enzootic for at least one Helicobacter species were mated, and the pups produced were fostered on laboratory mice 24 h after birth. After 2 rounds of fostering, both foster dams and pups were free of Helicobacter spp. as determined by fecal PCR analysis. Removal of Helicobacter infection through neonatal fostering has not been described previously for Peromyscus maniculatus. PMID:26224445

  4. Dynamics of the plague–wildlife–human system in Central Asia are controlled by two epidemiological thresholds

    PubMed Central

    Samia, Noelle I.; Kausrud, Kyrre Linné; Heesterbeek, Hans; Ageyev, Vladimir; Begon, Mike; Chan, Kung-Sik; Stenseth, Nils C.

    2011-01-01

    Plague (caused by the bacterium Yersinia pestis) is a zoonotic reemerging infectious disease with reservoirs in rodent populations worldwide. Using one-half of a century of unique data (1949–1995) from Kazakhstan on plague dynamics, including data on the main rodent host reservoir (great gerbil), main vector (flea), human cases, and external (climate) conditions, we analyze the full ecoepidemiological (bubonic) plague system. We show that two epidemiological threshold quantities play key roles: one threshold relating to the dynamics in the host reservoir, and the second threshold relating to the spillover of the plague bacteria into the human population. PMID:21856946

  5. An overview of restraint and blood collection techniques in exotic pet practice.

    PubMed

    Dyer, Stephen M; Cervasio, Erika L

    2008-09-01

    As more data about blood test results become available, blood sampling becomes increasingly important as a diagnostic tool. The increased availability of biochemistry analyzers that sample small volumes of blood has made it possible to get diagnostic profiles and hematology results from pets that have only small volumes of blood to contribute. This article describes techniques for restraint, phlebotomy, and sample preparation of several of the more popular exotic animals in the pet trade. The species covered include birds, lizards, chelonians, snakes, frogs, salamanders, fish, rabbits, ferrets, guinea pigs, mice, rats, hamsters, gerbils, hedgehogs, sugar gliders, and giant spiders (tarantulas). PMID:18675727

  6. Advanced diagnostic approaches and current management of internal disorders of select species (rodents, sugar gliders, hedgehogs).

    PubMed

    Evans, Erika E; Souza, Marcy J

    2010-09-01

    African pygmy and European hedgehogs, sugar gliders, and rodents such as rats, mice, gerbils, hamsters, guinea pigs, and chinchillas are becoming increasingly popular as pets in the United States, and more practitioners are being asked to examine, diagnose, and treat these animals for a bevy of disorders and diseases. Many procedures and techniques used in traditional small and large animal medicine are used for these species, with minor adaptations or considerations. This article examines available diagnostic tools and treatment methodologies for use in hedgehogs, sugar gliders, and selected rodents. PMID:20682430

  7. Morphological and molecular identification of a lung fluke, Paragonimus macrorchis (Trematoda, Paragonimidae), found in central Lao PDR and its molecular phylogenetic status in the genus Paragonimus.

    PubMed

    Sanpool, Oranuch; Intapan, Pewpan Maleewong; Thanchomnang, Tongjit; Janwan, Penchom; Laymanivong, Sakhone; Sugiyama, Hiromu; Maleewong, Wanchai

    2015-12-01

    Paragonimus macrorchis is rather a rare species with sporadic discovery reports. To date, little is known about morphological features and the molecular phylogenetic status of P. macrorchis. Here we provide such information on P. macrorchis, of which metacercariae were collected from freshwater crabs in Khammouane Province, central Lao PDR. After morphological observation, metacercariae were excysted and were injected intra-peritoneally into Mongolian gerbils. Paragonimus adult worms were collected from the lungs of experimental gerbils 45 days after infection. A small piece of body tissue was cut at the posterior part of each adult worm for genomic DNA extraction. Then, the adult worms were stained and mounted for morphological identification. The second internal transcribed spacer region (ITS2) of rDNA and partial cytochrome c oxidase subunit 1 (cox1) gene were amplified using PCR method and sequenced. The results of morphological identification of metacercariae and adult worms together with their DNA sequences of ITS2 and partial cox1 gene clearly show that the specimens we collected in the central Lao PDR were P. macrorchis. Phylogenetic analyses revealed that P. macrorchis forms an independent cluster from other Paragonimus species in Asia. PMID:26170107

  8. Overexpression of specific cysteine peptidases confers pathogenicity to a nonpathogenic Entamoeba histolytica clone.

    PubMed

    Matthiesen, Jenny; Bär, Ann-Katrein; Bartels, Anne-Kathrin; Marien, Dennis; Ofori, Susann; Biller, Laura; Tannich, Egbert; Lotter, Hannelore; Bruchhaus, Iris

    2013-01-01

    Cysteine peptidases (CPs) of Entamoeba histolytica are considered to be important pathogenicity factors. Previous studies have found that under standard axenic culture conditions, only four (ehcp-a1, ehcp-a2, ehcp-a5, and ehcp-a7) out of 35 papain-like ehcp genes present in the E. histolytica genome are expressed at high levels. Little is known about the expression of CPs in E. histolytica during amoebic liver abscess (ALA) formation. In the current study, a quantitative real-time PCR assay was developed to determine the expression of the various ehcp genes during ALA formation in animal models. Increased expression of four ehcp genes (ehcp-a3, -a4, -a10, and -c13) was detected in the gerbil and mouse models. Increased expression of another three ehcp genes (ehcp-a5, -a6, and -a7) was detected in the mouse model only, and two other ehcp genes (ehcp-b8 and -b9) showed increased expression in the gerbil model only. Trophozoites of the nonpathogenic E. histolytica HM-1:IMSS clone A1, which was unable to induce ALAs, were transfected with vectors enabling overexpression of those CPs that are expressed at high levels under culture conditions or during ALA formation. Interestingly, overexpression of ehcp-b8, -b9, and -c13 restored the pathogenic phenotype of the nonpathogenic clone A1 whereas overexpression of various other peptidase genes had no effect on the pathogenicity of this clone. PMID:23532975

  9. Oenanthe Javanica Extract Protects Against Experimentally Induced Ischemic Neuronal Damage via its Antioxidant Effects

    PubMed Central

    Park, Joon Ha; Cho, Jeong Hwi; Kim, In Hye; Ahn, Ji Hyeon; Lee, Jae-Chul; Chen, Bai Hui; Shin, Bich-Na; Tae, Hyun-Jin; Yoo, Ki-Yeon; Hong, SeongKweon; Kang, Il Jun; Won, Moo-Ho; Kim, Jong-Dai

    2015-01-01

    Background: Water dropwort (Oenanthe javanica) as a popular traditional medicine in Asia shows various biological properties including antioxidant activity. In this study, we firstly examined the neuroprotective effect of Oenanthe javanica extract (OJE) in the hippocampal cornus ammonis 1 region (CA1 region) of the gerbil subjected to transient cerebral ischemia. Methods: Gerbils were established by the occlusion of common carotid arteries for 5 min. The neuroprotective effect of OJE was estimated by cresyl violet staining. In addition, 4 antioxidants (copper, zinc superoxide dismutase [SOD], manganese SOD, catalase, and glutathione peroxidase) immunoreactivities were investigated by immunohistochemistry. Results: Pyramidal neurons in the CA1 region showed neuronal death at 5 days postischemia; at this point in time, all antioxidants immunoreactivities disappeared in CA1 pyramidal neurons and showed in many nonpyramidal cells. Treatment with 200 mg/kg, not 100 mg/kg, OJE protected CA1 pyramidal neurons from ischemic damage. In addition, 200 mg/kg OJE treatment increased or maintained antioxidants immunoreactivities. Especially, among the antioxidants, glutathione peroxidase immunoreactivity was effectively increased in the CA1 pyramidal neurons of the OJE-treated sham-operated and ischemia-operated groups. Conclusion: Our present results indicate that treatment with OJE can protect neurons from transient ischemic damage and that the neuroprotective effect may be closely associated with increased or maintained intracellular antioxidant enzymes by OJE. PMID:26521793

  10. Adaptation in sound localization: from GABA(B) receptor-mediated synaptic modulation to perception.

    PubMed

    Stange, Annette; Myoga, Michael H; Lingner, Andrea; Ford, Marc C; Alexandrova, Olga; Felmy, Felix; Pecka, Michael; Siveke, Ida; Grothe, Benedikt

    2013-12-01

    Across all sensory modalities, the effect of context-dependent neural adaptation can be observed at every level, from receptors to perception. Nonetheless, it has long been assumed that the processing of interaural time differences, which is the primary cue for sound localization, is nonadaptive, as its outputs are mapped directly onto a hard-wired representation of space. Here we present evidence derived from in vitro and in vivo experiments in gerbils indicating that the coincidence-detector neurons in the medial superior olive modulate their sensitivity to interaural time differences through a rapid, GABA(B) receptor-mediated feedback mechanism. We show that this mechanism provides a gain control in the form of output normalization, which influences the neuronal population code of auditory space. Furthermore, psychophysical tests showed that the paradigm used to evoke neuronal GABA(B) receptor-mediated adaptation causes the perceptual shift in sound localization in humans that was expected on the basis of our physiological results in gerbils. PMID:24141311

  11. Point-based warping with optimized weighting factors of displacement vectors

    NASA Astrophysics Data System (ADS)

    Pielot, Ranier; Scholz, Michael; Obermayer, Klaus; Gundelfinger, Eckart D.; Hess, Andreas

    2000-06-01

    The accurate comparison of inter-individual 3D image brain datasets requires non-affine transformation techniques (warping) to reduce geometric variations. Constrained by the biological prerequisites we use in this study a landmark-based warping method with weighted sums of displacement vectors, which is enhanced by an optimization process. Furthermore, we investigate fast automatic procedures for determining landmarks to improve the practicability of 3D warping. This combined approach was tested on 3D autoradiographs of Gerbil brains. The autoradiographs were obtained after injecting a non-metabolized radioactive glucose derivative into the Gerbil thereby visualizing neuronal activity in the brain. Afterwards the brain was processed with standard autoradiographical methods. The landmark-generator computes corresponding reference points simultaneously within a given number of datasets by Monte-Carlo-techniques. The warping function is a distance weighted exponential function with a landmark- specific weighting factor. These weighting factors are optimized by a computational evolution strategy. The warping quality is quantified by several coefficients (correlation coefficient, overlap-index, and registration error). The described approach combines a highly suitable procedure to automatically detect landmarks in autoradiographical brain images and an enhanced point-based warping technique, optimizing the local weighting factors. This optimization process significantly improves the similarity between the warped and the target dataset.

  12. In vitro and in vivo studies of macrophage functions in amebiasis.

    PubMed Central

    Denis, M; Chadee, K

    1988-01-01

    Experimental intrahepatic inoculation of the gerbil with Entamoeba histolytica trophozoites was used as a model of liver amebiasis to study the cellular immune response elicited by the parasite. It was shown that abscess-derived macrophages (5 to 20 days old) were deficient in their capacity to develop a respiratory burst, to secrete and express membrane-bound interleukin-1-like activity, and to kill E. histolytica trophozoites as well as to respond to lymphokines in vitro. However, macrophages isolated from the spleen and peritoneal cavities from the same infected animals were not significantly down regulated in these functions. Splenocytes from infected gerbils were shown to develop a strong responsiveness to amebic antigen, whereas their response to concanavalin A was suppressed. Crude E. histolytica extracts or conditioned medium down regulated murine BALB/c macrophage accessory and effector cell functions in vitro in a manner similar to abscess-derived macrophages, whereas crude extracts of the nonvirulent E. histolytica-like Laredo strain did not. Our results indicate that intrinsic or secreted products or both from E. histolytica are actively regulating macrophage functions at the abscess site and can possibly mediate other immunoregulatory mechanisms at distant targets. PMID:2903124

  13. Estimation of stapes piston motion from uniaxial interferometer measurements along observation directions at an angle with the piston axis is prone to substantial errors

    NASA Astrophysics Data System (ADS)

    Decraemer, Willem F. S.; Khanna, Shyam M.; Dirckx, Joris J. J.

    2006-06-01

    We have shown that the vibration of the stapes in human, cat and gerbil exhibits all 3-D components of translation and rotation, but also that non-piston components do not contribute to the transmission path. In most experiments access for direct measurement of stapes motion in line with the piston axis is not available and piston motion is estimated from single component interferometric measurements done under observation directions that make angles up to 50° with the piston axis. We used a heterodyne microscope/interferometer to measure the vibration velocity of the stapes in human, cat and gerbil from different observation angles and calculated the complete set of 3-D motion components for the stapes. Using micro CT scans of the experimental ears, we could express the components in an intrinsic reference system and foretell the motion component that will be obtained when a single axis interferometric measurement is done under various angles with the piston axis. For low frequencies (f<2kHz) a cosine factor provides a good correction for the axis off-set, at higher frequencies the piston component can not correctly be estimated from a single off-axis observation. We will show that this may lead to serious misinterpretations of experimental results.

  14. Metagonimus yokogawai: metacercariae survey in fishes and its development to adult worms in various rodents.

    PubMed

    Li, Ming-Hsien; Huang, Hai-I; Chen, Pei-Lain; Huang, Chiung-Hua; Chen, Yu-Hsuan; Ooi, Hong-Kean

    2013-04-01

    A parasitological survey for Metagonimus yokogawai metacercariae was carried out by examining a total of 321 freshwater fish comprising of 7 species. Of the 321 fish samples examined, 182 (56.7%) were found to be infected with M. yokogawai metacercariae. The prevalence of M. yokogawai metacercariae in Opsariichthys pachycephalus was 93.4% (86/92), Zacco platypus 75.0% (30/40), Distoechodon turmirostris 61.3% (38/62), Varicorhinus barbatulus 56.5% (13/23), Hemibarbus labeo 33.3% (1/3), Acrossocheilus formosanus 15.9% (14/88), and 0% in Sinibrama macrops (0/13), respectively. This is the first record of M. yokogawai infection in Z. platypus, D. turmirostris, V. barbatulus, and H. labeo in Taiwan. The major site of predilection of the metacercariae in the fishes was in the scale, but some metacercariae were also observed in the flesh and fins. The M. yokogawai metacercariae were orally inoculated into mice, rat, gerbil, and golden hamster to study their infectivity and also to obtain the adult worms for taxonomic study. Worm recovery in hamsters was 75.3%, in mice was 70.0%, in rats was 23.3%, and in gerbils was 6.0%, respectively. Moreover, larger worms were recovered from the golden hamster. Golden hamster was thus found to be the most susceptible experimental rodent host for the infectivity study of Metagonimus. Besides M. yokogawai, metacercariae of Centrocestus formosanus was also observed in the fishes examined. PMID:23388732

  15. Transferring isolated mitochondria into tissue culture cells

    PubMed Central

    Yang, Yi-Wei; Koob, Michael D.

    2012-01-01

    We have developed a new method for introducing large numbers of isolated mitochondria into tissue culture cells. Direct microinjection of mitochondria into typical mammalian cells has been found to be impractical due to the large size of mitochondria relative to microinjection needles. To circumvent this problem, we inject isolated mitochondria through appropriately sized microinjection needles into rodent oocytes or single-cell embryos, which are much larger than tissue culture cells, and then withdraw a ‘mitocytoplast’ cell fragment containing the injected mitochondria using a modified holding needle. These mitocytoplasts are then fused to recipient cells through viral-mediated membrane fusion and the injected mitochondria are transferred into the cytoplasm of the tissue culture cell. Since mouse oocytes contain large numbers of mouse mitochondria that repopulate recipient mouse cells along with the injected mitochondria, we used either gerbil single-cell embryos or rat oocytes to package injected mouse mitochondria. We found that the gerbil mitochondrial DNA (mtDNA) is not maintained in recipient rho0 mouse cells and that rat mtDNA initially replicated but was soon completely replaced by the injected mouse mtDNA, and so with both procedures mouse cells homoplasmic for the mouse mtDNA in the injected mitochondria were obtained. PMID:22753025

  16. The invasive potential of Giardia intestinalis in an in vivo model

    PubMed Central

    Reynoso-Robles, R.; Ponce-Macotela, M.; Rosas-López, L. E.; Ramos-Morales, A.; Martínez–Gordillo, M. N.; González-Maciel, A.

    2015-01-01

    Giardiasis is a neglected parasitic disease that affects primarily children, in whom it delays physical and mental development. The pathophysiology of giardiasis in not well understood, and most reports have identified Giardia intestinalis trophozoites only in the lumen and on the brush border of the small intestine. We identified Giardia trophozoites within the epithelium of the small intestine of a lactose intolerance patient. The Giardia trophozoites were obtained and cultured in vitro. In addition, we demonstrated Giardia trophozoite invasion in an animal model. Giardia trophozoites invaded the intestinal mucosa and submucosa of infected gerbils. The invasive trophozoites were observed at 21, 30 and 60 days age, and the average numbers of invaded sites were 17 ± 5, 15 ± 4, and 9 ± 3, respectively. We found trophozoites between epithelial cells, at the base of empty goblet cells, in lacteal vessels and within the submucosa. The morphological integrity of the invasive trophozoites was demonstrated via electron microscopy. The analysis of the gerbils infected with the trophozoites of the WB reference strain did not show intraepithelial trophozoites. These results demonstrate another Giardia pathogenic mechanism, opening the door to numerous future studies. PMID:26470844

  17. The invasive potential of Giardia intestinalis in an in vivo model.

    PubMed

    Reynoso-Robles, R; Ponce-Macotela, M; Rosas-López, L E; Ramos-Morales, A; Martínez-Gordillo, M N; González-Maciel, A

    2015-01-01

    Giardiasis is a neglected parasitic disease that affects primarily children, in whom it delays physical and mental development. The pathophysiology of giardiasis in not well understood, and most reports have identified Giardia intestinalis trophozoites only in the lumen and on the brush border of the small intestine. We identified Giardia trophozoites within the epithelium of the small intestine of a lactose intolerance patient. The Giardia trophozoites were obtained and cultured in vitro. In addition, we demonstrated Giardia trophozoite invasion in an animal model. Giardia trophozoites invaded the intestinal mucosa and submucosa of infected gerbils. The invasive trophozoites were observed at 21, 30 and 60 days age, and the average numbers of invaded sites were 17 ± 5, 15 ± 4, and 9 ± 3, respectively. We found trophozoites between epithelial cells, at the base of empty goblet cells, in lacteal vessels and within the submucosa. The morphological integrity of the invasive trophozoites was demonstrated via electron microscopy. The analysis of the gerbils infected with the trophozoites of the WB reference strain did not show intraepithelial trophozoites. These results demonstrate another Giardia pathogenic mechanism, opening the door to numerous future studies. PMID:26470844

  18. Animal Models for Echinostoma malayanum Infection: Worm Recovery and Some Pathology.

    PubMed

    Songsri, Jiraporn; Aukkanimart, Ratchadawan; Boonmars, Thidarut; Ratanasuwan, Panaratana; Laummaunwai, Porntip; Sriraj, Pranee; Sripan, Panupan

    2016-02-01

    Echinostomes are intestinal trematodes that infect a wide range of vertebrate hosts, including humans, in their adult stage and also parasitize numerous invertebrate and cold-blooded vertebrate hosts in their larval stages. The purpose of this study was to compare Echinostoma malayanum parasite growth, including worm recovery, body size of adult worms, eggs per worm, eggs per gram of feces, and pathological changes in the small intestine of experimental animals. In this study, 6-8-week-old male hamsters, rats, mice, and gerbils were infected with echinostome metacercariae and then sacrificed at day 60 post-infection. The small intestine and feces of each infected animal were collected and then processed for analysis. The results showed that worm recovery, eggs per worm, and eggs per gram of feces from all infected hamsters were higher compared with infected rats and mice. However, in infected gerbils, no parasites were observed in the small intestine, and there were no parasite eggs in the feces. The volume of eggs per gram of feces and eggs per worm were related to parasite size. The results of histopathological changes in the small intestine of infected groups showed abnormal villi and goblet cells, as evidenced by short villi and an increase in the number and size of goblet cells compared with the normal control group. PMID:26951978

  19. Animal Models for Echinostoma malayanum Infection: Worm Recovery and Some Pathology

    PubMed Central

    Songsri, Jiraporn; Aukkanimart, Ratchadawan; Boonmars, Thidarut; Ratanasuwan, Panaratana; Laummaunwai, Porntip; Sriraj, Pranee; Sripan, Panupan

    2016-01-01

    Echinostomes are intestinal trematodes that infect a wide range of vertebrate hosts, including humans, in their adult stage and also parasitize numerous invertebrate and cold-blooded vertebrate hosts in their larval stages. The purpose of this study was to compare Echinostoma malayanum parasite growth, including worm recovery, body size of adult worms, eggs per worm, eggs per gram of feces, and pathological changes in the small intestine of experimental animals. In this study, 6-8-week-old male hamsters, rats, mice, and gerbils were infected with echinostome metacercariae and then sacrificed at day 60 post-infection. The small intestine and feces of each infected animal were collected and then processed for analysis. The results showed that worm recovery, eggs per worm, and eggs per gram of feces from all infected hamsters were higher compared with infected rats and mice. However, in infected gerbils, no parasites were observed in the small intestine, and there were no parasite eggs in the feces. The volume of eggs per gram of feces and eggs per worm were related to parasite size. The results of histopathological changes in the small intestine of infected groups showed abnormal villi and goblet cells, as evidenced by short villi and an increase in the number and size of goblet cells compared with the normal control group. PMID:26951978

  20. Spatial extent of cochlear infrared neural stimulation determined by tone-on-light masking

    NASA Astrophysics Data System (ADS)

    Matic, Agnella Izzo; Walsh, Joseph T.; Richter, Claus-Peter

    2011-11-01

    Artificial neural stimulation is widely used in clinic, rehabilitation, and research. One of the limitations of electrical stimulation is the current spread in tissue. Recently, pulsed mid-infrared laser stimulation of nerves has been investigated as an alternative stimulation method. The likely benefits of infrared neural stimulation (INS) include spatial selectivity of stimulation, noncontact mode of operation, and the lack of stimulation artifact in simultaneous electrical recordings. The hypothesis for this study is that INS of the cochlear spiral ganglion at low pulse energy is as spatially selective as low-level tonal stimulation of the cochlea. Spatial selectivity was measured using a masking method. An optical pulse with fixed optical parameters was delivered through a 200-μm diameter optical fiber. An acoustic tone, variable in frequency and level, was presented simultaneously with the optical pulse. Tone-on-light masking in gerbils revealed tuning curves with best frequencies between 5.3 and 11.4 kHz. The width of the tone-on-light tuning curves was similar to the width of tone-on-tone tuning curves. The results indicate that the spatial area of INS in the gerbil cochlea is similar to the cochlear area excited by a low level acoustic tone, showing promising results for future use of INS in implantable cochlear prostheses.

  1. Floating in situ gelling system of acetohydroxamic acid for clearance of H. pylori.

    PubMed

    Rajinikanth, Paruvathanahalli Siddalingam; Mishra, Brahmeshwar

    2008-06-01

    The objective of this study was to develop a novel floating in situ gel system for sustained drug delivery of acetohydroxamic acid (FIGA) for eradication of Helicobacter pylori (H. pylori). The FIGA was prepared by dissolving the different concentration of gellan in deionized water at 80 degrees C. Different concentration of drug and calcium carbonate as floating agents were dispersed with stirring. In vitro results revealed that in situ gelling formulation forms rigid gels instantaneously and floated for longed period time of time in SGF pH 1.2. The formulation parameters, such as concentration of polymer, concentration of calcium carbonate, and concentration of drug, affected the in vitro drug release characteristic significantly. Absence of drug-polymer interaction was confirmed by differential scanning calorimetry analysis. The in vivo H. pylori clearance efficacy of prepared FIGA in reference to acetohydroxamic acid suspension following repeated oral administration to H. pylori-infected Mongolian gerbils was examined by microbial culture method. FIGA showed a significant anti-H. pylori effect in the in vivo gerbil model. It was noted that the required amount of acetohydroxamic acid for eradication of H. pylori was very less in FIGA than in the corresponding acetohydroxamic acid suspension. From the above results, it was concluded that the floating in situ gelling system has feasibility for forming rigid gels in the stomach and eradicated H. pylori from the gastrointestinal tract more effectively than acetohydroxamic acid suspension because of the prolonged gastrointestinal residence time of the formulation. PMID:18568907

  2. Prevention of hyperoxia-induced alterations in synaptosomal membrane-associated proteins by N-tert-butyl-alpha-phenylnitrone and 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (Tempol).

    PubMed

    Howard, B J; Yatin, S; Hensley, K; Allen, K L; Kelly, J P; Carney, J; Butterfield, D A

    1996-11-01

    Hyperoxia has been considered a model of free radical reactive oxygen species production in aging and age-related disorders. Previously, we studied the membrane protein alterations that occur during hyperoxia; we found that exposure of young animals to 24 h of hyperoxia provided the greatest degree of oxidation of cortical synaptosomal membrane proteins. We reasoned that free radical oxidation was involved in this protein oxidation. In accordance, in the current study we investigated the protective nature of two known free radical scavengers, N-tert-butyl-alpha-phenylnitrone (PBN) and 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (Tempol), against 24-h hyperoxia damage. The three techniques used in this study were electron paramagnetic resonance (EPR) protein-specific spin labeling, assay of the activity of the oxidatively sensitive enzyme glutamine synthetase (GS), and measurement of protein carbonyl content. Before hyperoxia, gerbils received intraperitoneal injections of varying concentrations of either of the two free radical scavengers. After 30 min, the gerbils were exposed to 90-100% O2 for 24 h. For the spin labeling experiments, cortical synaptosomes were isolated from gerbils. The membrane proteins were spin labeled with the thiol-specific label MAL-6 (2,2,6,6-tetramethyl-4-maleimidopiperidin-1-oxyl). As in our earlier study, the EPR spectral parameter of MAL-6-labeled membranes, the W/S ratio, decreased with hyperoxia (p < 0.00001). This effect was lessened significantly with administration of PBN (p < 0.0003) or Tempol (p < 0.00003). For the GS and protein carbonyl assays, cortical proteins were used. The activity of the GS decreased with hyperoxia (p < 0.000005), and this effect likewise was lessened with administration of PBN (p < 0.004) or Tempol (p < 0.002). The protein carbonyl content increased with hyperoxia (p < 0.0002), and there was a protective effect found with Tempol (p < 0.000001). The optimum doses for PBN and Tempol were 20 and 5 mg

  3. Mapping the distribution of the main host for plague in a complex landscape in Kazakhstan: An object-based approach using SPOT-5 XS, Landsat 7 ETM+, SRTM and multiple Random Forests

    PubMed Central

    Wilschut, L.I.; Addink, E.A.; Heesterbeek, J.A.P.; Dubyanskiy, V.M.; Davis, S.A.; Laudisoit, A.; M.Begon; Burdelov, L.A.; Atshabar, B.B.; de Jong, S.M.

    2013-01-01

    Plague is a zoonotic infectious disease present in great gerbil populations in Kazakhstan. Infectious disease dynamics are influenced by the spatial distribution of the carriers (hosts) of the disease. The great gerbil, the main host in our study area, lives in burrows, which can be recognized on high resolution satellite imagery. In this study, using earth observation data at various spatial scales, we map the spatial distribution of burrows in a semi-desert landscape. The study area consists of various landscape types. To evaluate whether identification of burrows by classification is possible in these landscape types, the study area was subdivided into eight landscape units, on the basis of Landsat 7 ETM+ derived Tasselled Cap Greenness and Brightness, and SRTM derived standard deviation in elevation. In the field, 904 burrows were mapped. Using two segmented 2.5 m resolution SPOT-5 XS satellite scenes, reference object sets were created. Random Forests were built for both SPOT scenes and used to classify the images. Additionally, a stratified classification was carried out, by building separate Random Forests per landscape unit. Burrows were successfully classified in all landscape units. In the ‘steppe on floodplain’ areas, classification worked best: producer's and user's accuracy in those areas reached 88% and 100%, respectively. In the ‘floodplain’ areas with a more heterogeneous vegetation cover, classification worked least well; there, accuracies were 86 and 58% respectively. Stratified classification improved the results in all landscape units where comparison was possible (four), increasing kappa coefficients by 13, 10, 9 and 1%, respectively. In this study, an innovative stratification method using high- and medium resolution imagery was applied in order to map host distribution on a large spatial scale. The burrow maps we developed will help to detect changes in the distribution of great gerbil populations and, moreover, serve as a unique

  4. The intestinal cestode Hymenolepis diminuta as a lead sink for its rat host in the industrial areas of Riyadh, Saudi Arabia

    PubMed Central

    Al-Quraishy, Saleh; Gewik, Mohamed M.; Abdel-Baki, Abdel-Azeem S.

    2013-01-01

    The present study sought to assess the potential of the cestode Hymenolepis diminuta as a bioindicator for lead accumulation in two industrial areas of the city of Riyadh, Saudi Arabia. Rats (Meriones libycus) were collected from two sites (industrial area II and Salbukh) in Riyadh. In the industrial area II, the mean levels of lead concentrations were found to be 1.96, 1.92, 1.4 and 30.72 μg/g in the rats’ liver, kidney and intestine, and in H. diminuta, respectively. In Salbukh, meanwhile, the lead concentrations were 1.63, 1.52, 1.20 and 21.31 μg/g in the rats’ liver, kidney, and intestine, and in H. diminuta, respectively. In addition, in industrial area II, compared with the liver, kidney and intestine of their host, the bioconcentration factors of lead were found to be, respectively, 15.6, 16 and 21.9 times higher in H. diminuta, and were 7.5, 8, and 10.2 times higher in the same organs compared to H. diminuta in Salbukh. The present study, therefore, proved that H. diminuta could be used as a bioindicator for heavy metal contamination in the industrial areas of the city of Riyadh. PMID:25183950

  5. Detection of Bartonella spp. in wild carnivores, hyraxes, hedgehog and rodents from Israel.

    PubMed

    Marciano, Odelya; Gutiérrez, Ricardo; Morick, Danny; King, Roni; Nachum-Biala, Yaarit; Baneth, Gad; Harrus, Shimon

    2016-09-01

    Bartonella infection was explored in wild animals from Israel. Golden jackals (Canis aureus), red foxes (Vulpes vulpes), rock hyraxes (Procavia capensis), southern white-breasted hedgehogs (Erinaceus concolor), social voles (Microtus socialis), Tristram's jirds (Meriones tristrami), Cairo spiny mice (Acomys cahirinus), house mice (Mus musculus) and Indian crested porcupines (Hystrix indica) were sampled and screened by molecular and isolation methods. Bartonella-DNA was detected in 46 animals: 9/70 (13%) golden jackals, 2/11 (18%) red foxes, 3/35 (9%) rock hyraxes, 1/3 (33%) southern white-breasted hedgehogs, 5/57 (9%) Cairo spiny mice, 25/43 (58%) Tristram's jirds and 1/6 (16%) house mice. Bartonella rochalimae and B. rochalimae-like were widespread among jackals, foxes, hyraxes and jirds. This report represents the first detection of this zoonotic Bartonella sp. in rock hyraxes and golden jackals. Moreover, DNA of Bartonella vinsonii subsp. berkhoffii, Bartonella acomydis, Candidatus Bartonella merieuxii and other uncharacterized genotypes were identified. Three different Bartonella strains were isolated from Tristram's jirds, and several genotypes were molecularly detected from these animals. Furthermore, this study reports the first detection of Bartonella infection in a southern hedgehog. Our study indicates that infection with zoonotic and other Bartonella species is widespread among wild animals and stresses their potential threat to public health. PMID:27210612

  6. Influence of plant maturity on the sensitivity of turfgrass species to ozone

    SciTech Connect

    Richards, G.A.; Mulchi, C.L.; Hall, J.R.

    1980-01-01

    The increased prevalence of phytotoxic levels of oxidants during inversions in urban regions prompted an evaluation of the sensitivities of turf species to different doses of ozone at several stages of plant development. Warm and cool season turfgrass species and cultivars were exposed in fumigation chambers to various concentrations of ozone then scored for vegetative damage. The warm season entries Meyer zoysiagrass (Zoysia japonica Steud.) and Tufcote bermudagrass (Cynodon doctylon L., Pers.) exhibited greater tolerance to ozone than the cool season entries which included tall fescue (Festuca arundinaceae Schreb), perennial ryegrass (Lolium perenne L.), bentgrass (Agrostic paulustris Huds.), red fescue (Festuca rubra L.), Kentucky bluegrass (Poa pratensis L.), and annual bluegrass (Poa annua L.). The cool season grases which exhibited the highest and lowest tolerance to ozone were Merion Kentucky bluegrass and annual bluegrass, respectively. Increasing the ozone exposure from 3.5 to 7.0 hours/day for 5 days at 0.1 ppM caused twice the level of vegetative damage. As a group, seedlings 9 to 14 days of age exhibited greater susceptibility and uniformity in treatment response than seedlings 66 to 71 days of age to ozone exposures of 0.3 to 0.5 ppM for 3 hours.

  7. Survey of Wild and Domestic Mammals for Infection with Leishmania infantum following an Outbreak of Desert Zoonotic Visceral Leishmaniasis in Jiashi, People's Republic of China

    PubMed Central

    Gao, Chun-hua; Wang, Jun-yun; Zhang, Song; Yang, Yue-tao; Wang, Yong

    2015-01-01

    In 2008 and 2009, an outbreak of desert-subtype zoonotic visceral leishmaniasis occurred in Jiashi county, Xinjiang, China. So far, no animal reservoir has been identified for this type of visceral leishmaniasis. Therefore, we surveyed the most common mammals (wild and domestic) for Leishmania infections during the outbreak in 2008 and 2009 in order to identify the source of the visceral leishmaniasis in this region. Spleen, liver, bone marrow and blood samples collected from 86 wood mice (Apodemus sylvaticus), 61midday jirds (Meriones meridianus) and 27 Yarkand hares (Lepus yarkandensis) were tested for the presence of Leishmania by microscopy, culture and PCR. All of the animals were found to be negative for Leishmania infections; On the other hand, Leishmania DNA was detected in blood samples collected from livestock reared in the outbreak area: 30.36% (17/56) of sheep, 21.57% (11/51) of goats, 17.78% (8/45) of cattle, and 21.62 (8/37) of donkeys were positive for Leishmania DNA by PCR. The amplified kDNA sequences from the livestock samples matched Leishmania DNA sequences isolated from patients with visceral leishmaniasis in the study area. We suggest that these domestic mammals are a possible reservoir host for Leishmania infantum in the outbreak area. PMID:26177101

  8. Use it or lose it: reproductive implications of ecological specialization in a haematophagous ectoparasite.

    PubMed

    Arbiv, A; Khokhlova, I S; Ovadia, O; Novoplansky, A; Krasnov, B R

    2012-06-01

    Using experimentally induced disruptive selection, we tested two hypotheses regarding the evolution of specialization in parasites. The 'trade-off' hypothesis suggests that adaptation to a specific host may come at the expense of a reduced performance when exploiting another host. The alternative 'relaxed selection' hypothesis suggests that the ability to exploit a given host would deteriorate when becoming obsolete. Three replicate populations of a flea Xenopsylla ramesis were maintained on each of two rodent hosts, Meriones crassus and Dipodillus dasyurus, for nine generations. Fleas maintained on a specific host species for a few generations substantially decreased their reproductive performance when transferred to an alternative host species, whereas they generally did not increase their performance on their maintenance host. The results support the 'relaxed selection' hypothesis of the evolution of ecological specialization in haematophagous ectoparasites, while suggesting that trade-offs are unlikely drivers of specialization. Further work is needed to study the extent by which the observed specializations are based on epigenetic or genetic modifications. PMID:22587845

  9. Transient-state mechanisms of wind-induced burrow ventilation.

    PubMed

    Turner, J Scott; Pinshow, Berry

    2015-01-15

    Burrows are common animal habitations, yet living in a burrow presents physiological challenges for its inhabitants because the burrow isolates them from sources and sinks for oxygen, carbon dioxide, water vapor and ammonia. Conventionally, the isolation is thought to be overcome by either diffusion gas exchange within the burrow or some means of capturing wind energy to power steady or quasi-steady bulk flows of air through it. Both are examples of what may be called 'DC' models, namely steady to quasi-steady flows powered by steady to quasi-steady winds. Natural winds, however, are neither steady nor quasi-steady, but are turbulent, with a considerable portion of the energy contained in so-called 'AC' (i.e. unsteady) components, where wind velocity varies chaotically and energy to power gas exchange is stored in some form. Existing DC models of burrow gas exchange do not account for this potentially significant source of energy for ventilation. We present evidence that at least two AC mechanisms operate to ventilate both single-opening burrows (of the Cape skink, Trachylepis capensis) and double-opening model burrows (of Sundevall's jird, Meriones crassus). We propose that consideration of the physiological ecology and evolution of the burrowing habit has been blinkered by the long neglect of AC ventilation. PMID:25609780

  10. Survey of Wild and Domestic Mammals for Infection with Leishmania infantum following an Outbreak of Desert Zoonotic Visceral Leishmaniasis in Jiashi, People's Republic of China.

    PubMed

    Gao, Chun-Hua; Wang, Jun-Yun; Zhang, Song; Yang, Yue-Tao; Wang, Yong

    2015-01-01

    In 2008 and 2009, an outbreak of desert-subtype zoonotic visceral leishmaniasis occurred in Jiashi county, Xinjiang, China. So far, no animal reservoir has been identified for this type of visceral leishmaniasis. Therefore, we surveyed the most common mammals (wild and domestic) for Leishmania infections during the outbreak in 2008 and 2009 in order to identify the source of the visceral leishmaniasis in this region. Spleen, liver, bone marrow and blood samples collected from 86 wood mice (Apodemus sylvaticus), 61midday jirds (Meriones meridianus) and 27 Yarkand hares (Lepus yarkandensis) were tested for the presence of Leishmania by microscopy, culture and PCR. All of the animals were found to be negative for Leishmania infections; On the other hand, Leishmania DNA was detected in blood samples collected from livestock reared in the outbreak area: 30.36% (17/56) of sheep, 21.57% (11/51) of goats, 17.78% (8/45) of cattle, and 21.62 (8/37) of donkeys were positive for Leishmania DNA by PCR. The amplified kDNA sequences from the livestock samples matched Leishmania DNA sequences isolated from patients with visceral leishmaniasis in the study area. We suggest that these domestic mammals are a possible reservoir host for Leishmania infantum in the outbreak area. PMID:26177101

  11. Density dependence of feeding success in haematophagous ectoparasites.

    PubMed

    Krasnov, B R; Hovhanyan, A; Khokhlova, I S; Degen, A A

    2007-09-01

    We studied the effect of density on feeding success of 2 fleas, Xenopsylla conformis and Xenopsylla ramesis, when exploiting rodents Meriones crassus and Gerbillus dasyurus. We tested 2 alternative hypotheses: (i) that intraspecific interference competition occurs and, thus, feeding success of a flea decreases with an increase in density and (ii) that facilitation via suppression of a host defence system occurs and thus, feeding success of a flea increases with an increase in density. The mean size of a bloodmeal and the proportion of highly engorged individuals in X. conformis feeding on both hosts were affected by density. When on G. dasyurus, both the size of a bloodmeal and the proportion of highly engorged individuals were lower at low (5-15 fleas per host) than at high (25-50 fleas per host) densities. The opposite was true when this flea fed on M. crassus. The mean bloodmeal size and proportions of highly engorged X. ramesis parasitizing either host were not affected by flea density. This study showed that the density dependence of feeding success of a flea (a) varied both between fleas and within-fleas between hosts and (b) indicated either intraspecific competition or facilitation via the host in a particular flea-host association. PMID:17445332

  12. Studies on rodents role as reservoir hosts of leishmaniasis with specical reference to their ectoparasites in Suez Governorate.

    PubMed

    Shoukry, Nahla M; El-Naggar, Mostafa H; Darwish, Ahmed B; Soliman, Belal A; El-Sawaf, Bahira M

    2006-04-01

    The distribution of rodents was studied in three different habitats. Seven rodent species were identified: Rattus norvegicus, R. alexandrinus, R. frugivorous, Mus musculus, Acomys russatus, Meriones sacramenti and Gerbillus pyramidum. The species distribution varied with the habitat type. The highest density of rodents was in July and August and the lowest one was in January. However, some species were collected all the year round. The rodents were investigated for the endo- and ecto-parasites. No Leishmania parasites were found. The ectoparasites were: Xenopsylla cheopis, Leptopsylla segnis and Ctenocephalides felis, Polyplax spinulos, Hyalomma dromedarii (nymph) and Echinolaelaps echidninus and Hemolaelaps glassgowi. Ecto-parasites were on rodents all year-round in domestic habitat and peridomestic habitats. In wild one, ecto-parasites activity was from March to December. The rodents' role as reservoir for L. major was experimentally studied. Rodents inoculated with L. major together with hamster and BALB-c mice developed cutaneous lesions. The active lesions, the rodents' ecological habitats and the presence of insect-vector may pave the way to an epidemic zoonotic leishmaniasis role. PMID:16605103

  13. Reproductive success in two species of desert fleas: density dependence and host effect.

    PubMed

    Khokhlova, Irina S; Hovhanyan, Anna; Krasnov, Boris R; Degen, A Allan

    2007-06-01

    We tested the hypothesis that a negative fitness-density relationship exists in haematophagous ectoparasites. We studied the effect of flea density on the number of blood meals necessary for starting oviposition and egg production in Xenopsylla conformis and Xenopsylla ramesis when exploiting two rodent hosts, Meriones crassus and Gerbillus dasyurus. The number of blood meals taken by a flea prior to first oviposition was similar in both flea species but was dependent on flea density and differed significantly between hosts. When parasitizing G. dasyurus, females of both flea species required a similar number of blood meals to start oviposition, independent of density. By contrast, fleas on M. crassus at higher densities needed less blood meals than at lower densities. Egg production of female fleas differed significantly between flea and host species and was affected by flea density. X. ramesis produced more eggs than X. conformis. When parasitizing G. dasyurus, density did not affect the number of eggs produced by X. conformis, however, when on M. crassus, this flea produced significantly less eggs at the highest density. The number of eggs produced by X. ramesis at high densities was significantly lower than at low densities when it parasitized either host species. Results of this study demonstrated that reproductive success of fleas was density dependent and, in general, decreased with an increase in density. However, the effect of density on reproductive performance was manifested differently on different host species. PMID:17562885

  14. In vivo coincidence detection in mammalian sound localization generates phase delays.

    PubMed

    Franken, Tom P; Roberts, Michael T; Wei, Liting; Golding, Nace L; Joris, Philip X

    2015-03-01

    Sound localization critically depends on detection of differences in arrival time of sounds at the two ears (acoustic delay). The fundamental mechanisms are debated, but all proposals include a process of coincidence detection and a separate source of internal delay that offsets the acoustic delay and determines neural tuning. We used in vivo patch-clamp recordings of binaural neurons in the Mongolian gerbil and pharmacological manipulations to directly compare neuronal input to output and to separate excitation from inhibition. Our results cannot be accounted for by existing models and reveal that coincidence detection is not an instantaneous process, but is instead shaped by the interaction of intrinsic conductances with preceding synaptic activity. This interaction generates an internal delay as an intrinsic part of the process of coincidence detection. The multiplication and time-shifting stages thought to extract synchronous activity in many brain areas can therefore be combined in a single operation. PMID:25664914

  15. Common procedures in hedgehogs, prairie dogs, exotic rodents, and companion marsupials.

    PubMed

    Johnson-Delaney, Cathy A

    2006-05-01

    Nondomesticated species are commonly being kept as companion animals. These include the African pygmy hedgehog (Atelerix albi-ventris), the North American black-tailed prairie dog (Cynomys lu-dovicianus), and exotic rodents such as the degu (Octodon degus)and duprasi or fat-tailed gerbil (Pachyuromys duprasi). Common companion marsupials include the sugar glider (Petaurus breviceps),Bennett's or Tammar (Dama) wallabies (Macropus rufogriseus rufo-griseus and Macropus eugenii, respectively), the Brazilian or South American gray short-tailed opossum (Monodelphis domestica), and the North American Virginia opossum (Didelphis virginiana). Although many of these animals are now bred domestically and are fairly docile when human-raised, they are essentially wild animals and hence have strong instincts to hide illness and pain. PMID:16759954

  16. Axenic cultivation and characterization of Giardia lamblia isolated from humans in Korea

    PubMed Central

    Yong, Tai-Soon; Yang, Hye-Won; Lee, Du-Ho; Lee, Kyungwon

    1999-01-01

    Inoculating of human fecal cysts to suckling Mongolian gerbils, two Giardia lamblia isolates, K1 and K2, were established as axenic cultures. Using this in vitro culture, both isolates were characterized as a "medium-rate grower" upon its growth pattern. These two Giardia isolates were grouped by using two genetic analysis. With genetic analysis of SSU-rDNA sequences, both K1 and K2 were found as members of Hopkins' group 1, despite some nucleotide differences noticed in K1 (5 differences/292 bases). The other genetic study used PCR-RFLP of the tim (triose phosphate isomerase) gene. Both of K1 and K2 were found to belong to Nash's group 2. Our results suggest that Nash's group 2 can not be a separate group, but a part of Hopkins' group 1. PMID:10388271

  17. Estimation of self-motion duration and distance in rodents

    PubMed Central

    Kautzky, Magdalena

    2016-01-01

    Spatial orientation and navigation rely on information about landmarks and self-motion cues gained from multi-sensory sources. In this study, we focused on self-motion and examined the capability of rodents to extract and make use of information about own movement, i.e. path integration. Path integration has been investigated in depth in insects and humans. Demonstrations in rodents, however, mostly stem from experiments on heading direction; less is known about distance estimation. We introduce a novel behavioural paradigm that allows for probing temporal and spatial contributions to path integration. The paradigm is a bisection task comprising movement in a virtual reality environment in combination with either timing the duration ran or estimating the distance covered. We performed experiments with Mongolian gerbils and could show that the animals can keep track of time and distance during spatial navigation. PMID:27293792

  18. Noncariogenic intense natural sweeteners.

    PubMed

    Kinghorn, A D; Kaneda, N; Baek, N I; Kennelly, E J; Soejarto, D D

    1998-09-01

    There is a definite relationship between the dietary consumption of sucrose and the incidence of dental caries. Noncaloric sucrose substitutes for use in the sweetening of foods, beverages, and medicines may be either synthetic compounds or natural products. In the United States, four potently sweet artificial sweeteners are approved, namely, saccharin, aspartame, acesulfame potassium, and sucralose. Highly sweet plant constituents are used in Japan and some other countries, including the diterpene glycoside stevioside and the protein thaumatin. Recent progress in a research project oriented towards the discovery and evaluation of novel potentially noncariogenic sweeteners from plants has focused on substances in the sesquiterpenoid, diterpenoid, triterpenoid, steroidal saponin, and proanthocyanidin structural classes. The feasibility of using Mongolian gerbil electrophysiological and behavioral assays to monitor the sweetness of plant extracts, chromatographic fractions, and pure isolates has been investigated. An in vivo cariogenicity study on the commercially available natural sweeteners stevioside and rebaudioside A has been carried out. PMID:9735874

  19. The role of the gastrointestinal microbiome in Helicobacter pylori pathogenesis

    PubMed Central

    Sheh, Alexander; Fox, James G

    2013-01-01

    The discovery of Helicobacter pylori overturned the conventional dogma that the stomach was a sterile organ and that pH values < 4 were capable of sterilizing the stomach. H. pylori are an etiological agent associated with gastritis, hypochlorhydria, duodenal ulcers, and gastric cancer. It is now appreciated that the human stomach supports a bacterial community with possibly 100s of bacterial species that influence stomach homeostasis. Other bacteria colonizing the stomach may also influence H. pylori-associated gastric pathogenesis by creating reactive oxygen and nitrogen species and modulating inflammatory responses. In this review, we summarize the available literature concerning the gastric microbiota in humans, mice, and Mongolian gerbils. We also discuss the gastric perturbations, many involving H. pylori, that facilitate the colonization by bacteria from other compartments of the gastrointestinal tract, and identify risk factors known to affect gastric homeostasis that contribute to changes in the microbiota. PMID:23962822

  20. Leishmania species: Detection and identification by nested PCR assay from skin samples of rodent reservoirs

    PubMed Central

    Akhavan, Amir Ahmad; Mirhendi, Hossein; Khamesipour, Ali; Alimohammadian, Mohammad Hossein; Rassi, Yavar; Bates, Paul; Kamhawi, Shaden; Valenzuela, Jesus G.; Arandian, Mohammad Hossein; Abdoli, Hamid; Jalali-zand, Niloufar; Jafari, Reza; Shareghi, Niloufar; Ghanei, Maryam; Yaghoobi-Ershadi, Mohammad Reza

    2010-01-01

    Many rodent species act as reservoir hosts of zoonotic cutaneous leishmaniasis in endemic areas. In the present study a simple and reliable assay based on nested PCR was developed for the detection and identification of Leishmania parasites from rodent skin samples. We designed Leishmania-specific primers that successfully amplified ITS regions of Leishmania major, Leishmania gerbilli and Leishmania turanica using nested PCR. Out of 95 field collected Rhombomys opimus, 21 were positive by microscopic examination and 48 by nested PCR. The percentage of gerbils infected with L. major, L. gerbilli and L. turanica was 3.2%, 1.1% and 27.4%, respectively. In 15.8% of the rodents, we found mixed natural infections by L. major and L. turanica, 1.1% by L. major and L. gerbilli, and 2.1% by the three species. We concluded that this method is simple and reliable for detecting and identifying Leishmania species circulating in rodent populations. PMID:20566364

  1. Imaging cochlear soft tissue displacement with coherent x-rays

    NASA Astrophysics Data System (ADS)

    Rau, Christoph; Richter, Claus-Peter

    2015-10-01

    At present, imaging of cochlear mechanics at mid-cochlear turns has not been accomplished. Although challenging, this appears possible with partially coherent hard x-rays. The present study shows results from stroboscopic x-ray imaging of a test object at audio frequencies. The vibration amplitudes were quantified. In a different set of experiments, an intact and calcified gerbil temporal bone was used to determine displacements of the reticular lamina, tectorial membrane, and Reissner’s membrane with the Lucas and Kanade video flow algorithm. The experiments validated high frequency x-ray imaging and imaging in a calcified cochlea. The present work is key for future imaging of cochlear micromechanics at a high spatial resolution.

  2. Inferring causality from relational data and designs: historical and contemporary lessons for research and clinical practice.

    PubMed

    Reynolds, C R

    1999-11-01

    My address to you today is born of frustration with the growing claims, evident in the research literature and in clinical reports that happen to cross my desk, of causation made on the basis of correlational data. I recall, as a sophomore in college, being taught early in my first experimental psychology course, "you cannot infer causality from correlation." This point was made adamant in my first face-to-face critique of an experimental psychology research paper by Dr. Robert T. Brown, who pointed out, in lowering my grade, that I had inferred organic causes to behavior patterns in gerbils based solely on correlational data. This caution was reiterated in my statistics courses until it must have been indelibly stamped upon my then still somewhat plastic brain. PMID:10806450

  3. Sex differences in the parental behavior of rodents.

    PubMed

    Lonstein, J S; De Vries, G J

    2000-08-01

    The reproductive strategy of many mammalian species that give birth to altricial young involves intense and prolonged care of their offspring. In most cases, the mother provides all nurturance, but in some cases fathers, older siblings, or unrelated conspecifics participate in parental care. The display of these behaviors by animals other than mothers is affected by numerous factors, including their sex. We herein review the literature on similarities and/or differences between male and female laboratory rodents (rats, mice, voles, gerbils, and hamsters) in their parental responsiveness and discuss how the parental behavior of males and females is influenced by hormones, developmental processes, and prior social experiences. Understanding the mechanisms that generate sex differences in the parental responsiveness of rodents may indicate how similar sex differences in parental care are generated in other mammals. PMID:10940441

  4. Glycinergic inhibition tunes coincidence detection in the auditory brainstem.

    PubMed

    Myoga, Michael H; Lehnert, Simon; Leibold, Christian; Felmy, Felix; Grothe, Benedikt

    2014-01-01

    Neurons in the medial superior olive (MSO) detect microsecond differences in the arrival time of sounds between the ears (interaural time differences or ITDs), a crucial binaural cue for sound localization. Synaptic inhibition has been implicated in tuning ITD sensitivity, but the cellular mechanisms underlying its influence on coincidence detection are debated. Here we determine the impact of inhibition on coincidence detection in adult Mongolian gerbil MSO brain slices by testing precise temporal integration of measured synaptic responses using conductance-clamp. We find that inhibition dynamically shifts the peak timing of excitation, depending on its relative arrival time, which in turn modulates the timing of best coincidence detection. Inhibitory control of coincidence detection timing is consistent with the diversity of ITD functions observed in vivo and is robust under physiologically relevant conditions. Our results provide strong evidence that temporal interactions between excitation and inhibition on microsecond timescales are critical for binaural processing. PMID:24804642

  5. Glycinergic inhibition tunes coincidence detection in the auditory brainstem

    PubMed Central

    Myoga, Michael H.; Lehnert, Simon; Leibold, Christian; Felmy, Felix; Grothe, Benedikt

    2014-01-01

    Neurons in the medial superior olive (MSO) detect microsecond differences in the arrival time of sounds between the ears (interaural time differences or ITDs), a crucial binaural cue for sound localization. Synaptic inhibition has been implicated in tuning ITD sensitivity, but the cellular mechanisms underlying its influence on coincidence detection are debated. Here we determine the impact of inhibition on coincidence detection in adult Mongolian gerbil MSO brain slices by testing precise temporal integration of measured synaptic responses using conductance-clamp. We find that inhibition dynamically shifts the peak timing of excitation, depending on its relative arrival time, which in turn modulates the timing of best coincidence detection. Inhibitory control of coincidence detection timing is consistent with the diversity of ITD functions observed in vivo and is robust under physiologically relevant conditions. Our results provide strong evidence that temporal interactions between excitation and inhibition on microsecond timescales are critical for binaural processing. PMID:24804642

  6. Unusually extensive karyotype reorganization in four congeneric Gerbillus species (Muridae: Gerbillinae).

    PubMed

    Aniskin, V M; Benazzou, T; Biltueva, L; Dobigny, G; Granjon, L; Volobouev, V

    2006-01-01

    Comparative analysis of the G- and C-banding patterns in four morphologically poorly differentiated Gerbillus species (G. pyramidum, G. perpallidus, G. tarabuli and G. occiduus) was carried out. These gerbils have similar karyotype morphology with 2n and NF equal to 38/76, 40/76, 40/78 and 40/80, respectively. Our study revealed that possibly 70 Robertsonian (Rb) fusions, two pericentric inversions, one tandem translocation and at least 13 non-identified rearrangements have occurred during the karyotypic evolution of these species. The number of chromosomal changes by which any of these species differ from each other ranges from 33 to 49. One Rb fusion was common to two of the species, with only a single autosome-gonosome translocation shared by all four, suggesting a monophyletic origin of these karyotypically highly divergent species. Based on the chromosomal data obtained here, the systematic and geographic implications for these North African species are also discussed. PMID:16276102

  7. Protecting against Noise Trauma by Sound Conditioning

    NASA Astrophysics Data System (ADS)

    NIU, X.; CANLON, B.

    2002-02-01

    The World Health Organization estimates that more than 12% of the world population is at risk for developing noise-induced hearing loss. At present, sound conditioning presents one means of reducing the deleterious effects of noise trauma. This phenomenon is now known to occur in a variety of mammals, including gerbils, chinchillas, guinea pigs, rabbits, rats, mice, and, of most importance, human subjects. A variety of sound conditioning paradigms have been proven successful in preventing morphological and physiological damage. Proposed mechanisms include the upregulation of endogenous antioxidants, the number of NMDA receptors, heat shock proteins, calcium buffering systems, and neurotrophic factors. Further studies are needed to understand the protective mechanisms afforded by sound conditioning. It is convincible that sound conditioning will benefit human subjects and provide a treatment for noise-induced hearing loss. The data presented in this review describe the current status and understanding of the phenomenon of sound conditioning.

  8. Basilar membrane vibration is not involved in the reverse propagation of otoacoustic emissions.

    PubMed

    He, W; Ren, T

    2013-01-01

    To understand how the inner ear-generated sound, i.e., otoacoustic emission, exits the cochlea, we created a sound source electrically in the second turn and measured basilar membrane vibrations at two longitudinal locations in the first turn in living gerbil cochleae using a laser interferometer. For a given longitudinal location, electrically evoked basilar membrane vibrations showed the same tuning and phase lag as those induced by sounds. For a given frequency, the phase measured at a basal location led that at a more apical location, indicating that either an electrical or an acoustical stimulus evoked a forward travelling wave. Under postmortem conditions, the electrically evoked emissions showed no significant change while the basilar membrane vibration nearly disappeared. The current data indicate that basilar membrane vibration was not involved in the backward propagation of otoacoustic emissions and that sounds exit the cochlea probably through alternative media, such as cochlear fluids. PMID:23695199

  9. Opto-electronic moire projector for real-time shape and deformation studies of the tympanic membrane

    NASA Astrophysics Data System (ADS)

    Dirckx, Joris J.; Decraemer, Willem F.

    1997-04-01

    Moire topography is a valuable technique for studying the shape and deformation of delicate biological structures such as the tympanic membrane. A projection moire method is described that can produce both shape and deformation fringes in real time, at a rate of 25 interferograms per second. The apparatus is based on electronic subtraction of the projected grating line image of the object and a reference grating line image stored in digital memory. The image field and fringe plane distance can be adjusted to the object dimensions. Using a fringe plane distance of 82 micrometers , a precision of 5 micrometers over a measuring depth of 0.4 mm is demonstrated by measurements on a spherical calibration object. The application to in vitro shape and deformation measurements of the gerbil tympanic membrane is demonstrated.

  10. Selectivity of optical stimulation in the auditory system

    NASA Astrophysics Data System (ADS)

    Izzo, Agnella D.; Pathria, Jyoti; Suh, Eul; Walsh, Joseph T., Jr.; Whitlon, Donna S.; Jansen, E. D.; Richter, Claus-Peter

    2006-02-01

    It is known that electrical current injected from cochlear implant contacts spreads within the cochlea, causing overlapping stimulation fields and possibly limiting the performance of cochlear implant users. We have investigated an alternative mechanism to stimulate auditory neurons in the gerbil cochlea using a laser, rather than electrical current. With the laser, it is possible to direct the light to a selected, known volume of tissue that is smaller than the electrically stimulated population of cells. In the present experiments, a transiently expressed transcription factor, c-FOS, was used to stain activated nerve cells. Immunohistochemical staining for c-FOS in the cochlea shows a small area of optical stimulation, which occurs directly opposite to the optical fiber. Additionally, masking data indicate that the laser can stimulate a small population of cells similar to an acoustic toneburst. Smaller populations of stimulated cells could reduce the amount of overlap in stimulation fields and allow more stimulation contacts in a neuroprothesis.

  11. Dp Phases in Mammalian Cochleae, Predicted from Liquid-Surface Formulas

    NASA Astrophysics Data System (ADS)

    Frosch, Reinhart

    2009-02-01

    Hydrodynamic formulas for mass-loaded spring-driven liquid-surface waves, together with cochlear parameters derived from experimental literature values of single-tone BM-vibration phases, are used to predict the phases of cubic DP's and DPOAE's. These predictions depend on the primary-tone level and on the category (low- or high-side) of the distortion; they agree [disagree] with recent fixed- f2 low-side DPOAE experiments by two different groups in Mongolian gerbil if the backward cochlear DP-wave is assumed to be a slow surface wave [a fast compression wave]. The weakness of DPOAE's, particularly of high-side ones, is argued to be due to destructive interference among slow backward DP-TW's from different parts of the DP generation zone.

  12. Host ABC transporter proteins may influence the efficacy of ivermectin and possibly have broader implications for the development of resistance in parasitic nematodes.

    PubMed

    Dooley, L A; Froese, E A; Chung, Y T; Burkman, E J; Moorhead, A R; Ardelli, B F

    2015-10-01

    ABC transporter proteins function to extrude compounds from the cell. These proteins present an obstacle for treatment and for overcoming drug resistance as they are expressed by both host and parasite, and function similarly. The contribution of host ABC proteins to drug efficacy was examined using ivermectin and a Brugia malayi model system. Parallel in vitro and in vivo experiments were conducted using equal concentrations of ivermectin. The motilities and fecundity of B. malayi exposed to ivermectin in vitro were significantly lower than those treated in vivo. The higher motilities were correlated with low concentrations of ivermectin in worms extracted from treated hosts. The expression of ABC proteins was significantly higher in worms treated in vitro compared to those treated in vivo as well as in gerbils treated with ivermectin than in non-treated controls. The results suggest that host ABC transporters may influence the efficacy of ivermectin. PMID:26143231

  13. [Localization of larvae of Neotrombicula (N) monticola (Trombiculidae) ticks on the vertebrates].

    PubMed

    Chirov, P A; Kharadov, A V

    2007-01-01

    The specific features of distribution of Neotrombicula (N) monticola Schluger et Davidov, 1967 on small mammals were studied in the Tien Shan montains (Kirghiz ridge). N. (N ) monticola was found to occur in all the places under study. Nine species of mammals (pigmy white-toothed shrew, dwarf hamster, tamarisk gerbil, Turkestan rat, long-tailed mouse, Tien Shan, Kirghiz, and silver voles, and wood mouse) were established to be feeders of larvae of the ticks. N. (N) monticola larvae were detected in three topographic zones and seven portions of the body of vertebral hosts. The inner auricle is the major site of tick attachment to the host. Preference of N. (N) monticola in selecting the host is likely to be based on the morphophysiological features of partners. PMID:17912838

  14. Novel insights on the role of CD8+ T cells and cytotoxic responses during Helicobacter pylori infection

    PubMed Central

    Kronsteiner, Barbara; Bassaganya-Riera, Josep; Philipson, Noah; Hontecillas, Raquel

    2014-01-01

    Helicobacter pylori chronically persists in 50% of the human population and causes serious gastric and duodenal pathologies in 15% of infected people. Research on the immune response to the infection has mainly focused on the induction of CD4+ T cell responses. Human studies emphasize the potential clinical relevance of CD8+ cytotoxic T lymphocytes, however this cell type has barely been reported in studies employing mouse or gerbil models. Traditionally characterized as an extracellular bacterium, H. pylori has been identified inside epithelial and immune cells. Similarly to other intracellular bacteria, H. pylori infection of macrophages can alter autophagy and phagosome processing. A novel animal model of H. pylori infection demonstrates for the first time the induction of cytotoxic CD8+ T cell responses in pigs and localization of intracellular H. pylori within lymphoid aggregates. Here, we discuss novel mechanisms of host-H. pylori interactions that could lead to the induction of cytotoxic responses. PMID:24755940

  15. Dynamic Aspects of Cochlear Microphonic Potentials

    NASA Astrophysics Data System (ADS)

    Meenderink, Sebastiaan W. F.; van der Heijden, Marcel

    2011-11-01

    Cochlear microphonic potentials were recorded from the Mongolian gerbil in response to low-frequency auditory stimuli. Provided that contamination of the potentials by the phase-locked neurophonic is avoided, these recordings can be interpreted "as if recorded from a single outer hair cell". It is found that the instantaneous I/O-curves resemble the well-known Boltzmann activation curve. The dynamic aspect of the I/O-curves does reveal hysteresis and a level-dependent gain that is not observed in static measures of these curves. We explore a model that simulates CM generation from hair cell populations, but find it inadequate to reproduce the data. Rather, there seem to be fast, adaptive mechanisms probably at the level of the transduction channels themselves.

  16. Occurrence of a house-infesting Tropical rat mite (Ornithonyssus bacoti) on murides and human beings.

    PubMed

    Beck, W

    2008-07-01

    In Germany there is little information available about the distribution of the Tropical rat mite (Ornithonyssus bacoti) in rodents. A few case reports show that this haematophagous mite species may also cause dermatitis in man. All developmental stages are exclusively bloodfeeder. Three children (4, 11 and 15 years old) of a family and a 23-year-old medical student were attacked by the Tropical rat mite. Prior to the consultation of our institution, the patients' conditions had been diagnosed as allergic dermatitis of unclear origin and treated by several antiphlogistic agents, however without success. The conclusive diagnosis, Tropical rat mite dermatitis, was based on the identification of the arthropod Ornithonyssus bacoti in the flats of the patients (husbandry of gerbils, etc.). The diagnosis of a Rat mite dermatitis requires the detection of the parasite, which is more likely to be found in the environment of its host than on the hosts' skin itself. PMID:18571117

  17. Outbreak of tropical rat mite (Ornithonyssus bacoti) dermatitis in a home for disabled persons.

    PubMed

    Baumstark, J; Beck, W; Hofmann, H

    2007-01-01

    Five mentally handicapped individuals living in a home for disabled persons in Southern Germany were seen in our outpatient department with pruritic, red papules predominantly located in groups on the upper extremities, neck, upper trunk and face. Over several weeks 40 inhabitants and 5 caretakers were affected by the same rash. Inspection of their home and the sheds nearby disclose