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Sample records for chinchilla

  1. Aflatoxicosis en chinchillas (Chinchilla lanigera

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    Sandra Cepeda A

    2011-04-01

    Full Text Available Objetivo. Determinar los efectos de las aflatoxinas (AF en chinchillas (Chinchilla lanigera por consumo de dietas contaminadas a diferentes concentraciones. Materiales y métodos. Un total de 20 chinchillas macho se distribuyeron en 5 grupos experimentales de 4 animales cada uno, los cuales recibieron diferentes niveles de aflatoxinas totales en el alimento durante 8 semanas: 0, 25, 50, 100 y 200 ppb. Semanalmente se determinó el consumo de alimento, el peso corporal individual y la mortalidad. Adicionalmente, al finalizar el experimento, se investigó el metabolismo hepático in vitro de la aflatoxina B1 (AFB1 en animales no expuestos al tóxico y se realizó examen histopatológico del hígado en todos los grupos. Resultados. El consumo de dietas contaminadas con aflatoxinas no causó efectos sobre el consumo de alimento ni hubo mortalidad. Solamente se observó disminución significativa (p<0.05 en la ganancia de peso corporal en los animales expuestos a 200 ppb en la dieta. Los niveles de 100 y 200 ppb (ng/g de aflatoxinas indujeron cambios leves a moderados en el hígado. El metabolismo microsomal de la AFB1 demostró la producción del epóxido de la AFB1 como único metabolito. Conclusiones. Los resultados del presente estudio demuestran que la chinchilla es altamente resistente a las aflatoxinas, pudiendo tolerar durante al menos dos meses niveles de aflatoxinas en el alimento que resultarían letales, en apenas unos pocos días, para especies sensibles como el cerdo o el perro.

  2. Taxonomy Icon Data: Chinchilla [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available Chinchilla Chinchilla lanigera Chordata/Vertebrata/Mammalia/Theria/Eutheria/etc. Chinchill...a_lanigera_L.png Chinchilla_lanigera_NL.png Chinchilla_lanigera_S.png Chinchilla_lanigera_NS.png http...://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Chinchilla+lanigera&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Chinchill...a+lanigera&t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Chinchill...a+lanigera&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Chinchilla+lanigera&t=NS ...

  3. Generalized Taenia crassiceps cysticercosis in a chinchilla (Chinchilla lanigera).

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    Basso, Walter; Rütten, Maja; Deplazes, Peter; Grimm, Felix

    2014-01-17

    Taenia crassiceps is a cestode parasite that uses carnivores as definitive hosts and rodents and rabbits as main intermediate hosts, but other animal species and humans may also get infected. One adult male chinchilla (Chinchilla lanigera) from an animal shelter in Switzerland presented widespread subcutaneous fluctuant swellings extended over the forehead, nose, face and thoracic regions with a progressive growth over 3 months. The thoracic swelling was surgically resected, and it consisted of numerous 3-4mm small transparent vesicles, mainly confined to the subcutaneous tissue, which were morphologically identified as cysticerci of T. crassiceps. The diagnosis was confirmed by PCR and DNA sequence analysis of fragments of the mitochondrial small subunit rRNA and NADH dehydrogenase subunit 1 genes. After 1.5 months, due to enlargement of the swollen areas and deterioration of the general health condition, the chinchilla was euthanized and a necropsy was performed. Thousands of small cysticerci were observed widespread in the subcutis, involving underlying musculature of the whole body, in the thoracic cavity, larynx, pharynx and in the retropharyngeal region. Additionally, three larger metacestodes were detected in the liver and morphologically and molecularly identified as Taenia taeniaeformis strobilocerci. The present case represents an indicator of the environmental contamination with Taenia eggs, highlighting the risk of infection for susceptible animals and humans. Besides the clinical relevance for pets, T. crassiceps is a zoonotic parasite and can be also cause of severe cysticercosis in humans.

  4. Stress-induced Cushing's syndrome in fur-chewing chinchillas.

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    Tisljar, Marina; Janić, D; Grabarević, Z; Simpraga, Borka; Marinculić, A; Pinter, Ljiljana; Janicki, Z; Nemanic, Ankica

    2002-01-01

    One of the most serious problems in the chinchilla industry is 'fur-chewing', when the chinchilla bites off areas of its own or some other animal's fur. The condition generally develops in both genders at the age of 6-8 months. In chinchilla farms in Croatia an incidence of 15-20% has been observed. A pathomorphological, microbiological and parasitological investigation was conducted on eleven 6- to 11-month-old chinchillas of both sexes with clinical symptoms of 'fur-chewing' and three chinchillas without such signs. Histopathology of the adrenal glands and of the chewed skin revealed changes typical of Cushing's syndrome in 'fur-chewed' chinchillas, such as hyperkeratinisation of the epidermis, epidermal atrophy, pronounced follicular and sebaceous gland atrophy, hyperkeratinisation of the follicles with comedo formations and the presence of calcium salts in subcutis.

  5. Isolation of a Campylobacter lanienae-like bacterium from laboratory chinchillas (Chinchilla laniger).

    Science.gov (United States)

    Turowski, E E; Shen, Z; Ducore, R M; Parry, N M A; Kirega, A; Dewhirst, F E; Fox, J G

    2014-12-01

    Routine necropsies of 27 asymptomatic juvenile chinchillas revealed a high prevalence of gastric ulcers with microscopic lymphoplasmacytic gastroenteritis and typhlocolitis. Polymerase chain reaction (PCR) analysis using Campylobacter genus-specific partial 16S rRNA primers revealed the presence of Campylobacter spp. DNA in the faeces of 12 of 27 animals (44.4%). Species-specific partial 16S rRNA PCR and sequencing confirmed that these animals were colonized with Campylobacter lanienae, a gram-negative, microaerophilic bacterium that was first identified on routine faecal screening of slaughterhouse employees and subsequently isolated from faeces of livestock. Campylobacter lanienae was isolated from the faeces of six PCR-positive animals and identified with species-specific PCR and full 16S rRNA sequencing. Phylogenetic analysis showed that these isolates clustered with C. lanienae strain NCTC 13004. PCR analysis of DNA extracted from gastrointestinal tissues revealed the presence of C. lanienae DNA in the caecum and colon of these chinchillas. Gastrointestinal lesions were scored and compared between C. lanienae-positive and C. lanienae-negative animals. There was no correlation between colonization status and lesion severity in the stomach, liver, duodenum, or colon. Possible routes of C. lanienae infection in chinchillas could include waterborne transmission and faecal-oral transmission from wild mice and rats or livestock. Based on these findings, the authors conclude that C. lanienae colonizes the lower bowel of chinchillas in the absence of clinical disease. This is the first report of C. lanienae in any rodent species. Campylobacter lanienae isolates from different mammalian species demonstrate heterogeneity by 16S rRNA sequence comparison. Analysis using rpoB suggests that isolates and clones currently identified as C. lanienae may represent multiple species or subspecies.

  6. Prevalence and analysis of Pseudomonas aeruginosa in chinchillas

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    Aoyama Naoki

    2010-11-01

    Full Text Available Abstract Background Chinchillas (Chinchilla laniger are popular as pets and are often used as laboratory animals for various studies. Pseudomonas aeruginosa is a major infectious agent that causes otitis media, pneumonia, septicaemia enteritis, and sudden death in chinchillas. This bacterium is also a leading cause of nosocomial infections in humans. To prevent propagation of P. aeruginosa infection among humans and animals, detailed characteristics of the isolates, including antibiotic susceptibility and genetic features, are needed. In this study, we surveyed P. aeruginosa distribution in chinchillas bred as pets or laboratory animals. We also characterized the isolates from these chinchillas by testing for antibiotic susceptibility and by gene analysis. Results P. aeruginosa was isolated from 41.8% of the 67 chinchillas included in the study. Slide agglutination and pulsed-field gel electrophoresis discriminated 5 serotypes and 7 unique patterns, respectively. For the antibiotic susceptibility test, 40.9% of isolates were susceptible to gentamicin, 77.3% to ciprofloxacin, 77.3% to imipenem, and 72.7% to ceftazidime. DNA analyses confirmed that none of the isolates contained the gene encoding extended-spectrum β-lactamases; however, 2 of the total 23 isolates were found to have a gene similar to the pilL gene that has been identified in the pathogenicity island of a clinical isolate of P. aeruginosa. Conclusions P. aeruginosa is widely spread in chinchillas, including strains with reduced susceptibility to the antibiotics and highly virulent strains. The periodic monitoring should be performed to help prevent the propagation of this pathogen and reduce the risk of infection from chinchillas to humans.

  7. The Chinchilla's vestibulo-ocular reflex

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    Merwin, W. H., Jr.; Wall, Conrad, III; Tomko, D. L.

    1989-01-01

    The horizontal vestibulo-ocular reflex (VOR) was measured and characterized in seven adult chinchillas using 0.01 to 1.0 Hz angular velocity sinusoids. Gains were less than compensatory, and were variable from day to day, but phases were highly repeatable both within and between animals. The best fitting transfer function to the average data of all animals had a dominant time constant of 7.5 sec, and an adaptation operator with a time constant of 24.0 sec. There were certain nonlinearities in the horizontal VOR of this animal, and it was difficult to elicit a robust optokinetic response. Results are discussed in relation to similar measurements in other species.

  8. Reproductive performance and weaning success in fur-chewing chinchillas (Chinchilla lanigera).

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    Galeano, María G; Cantarelli, Verónica I; Ruiz, Rubén D; Fiol de Cuneo, Marta; Ponzio, Marina F

    2014-09-01

    In captive chinchillas, one of the most challenging behavioral problems is the development of a stress-related abnormal repetitive behavior (ARB) known as "fur-chewing". We investigated whether there is a relationship between the severity of fur-chewing behavior and reproductive function in male and female chinchillas. Regardless of the severity of abnormal behavior, fur-chewing males did not show significant differences in seminal quality (sperm concentration, motility and viability; integrity of sperm membrane and acrosome) and the response to the process of semen collection (the number of stimuli needed to achieve ejaculation) when compared to those with normal behavior. Also, females showing normal or fur-chewing behavior presented similar reproductive performance in terms of number of litters per female per year and litter size. However, pup survival rate was lower (p=0.05) in fur-chewing females than in normal females. These results seem to be consistent with data suggesting non-significant effects of ARBs on reproductive performance.

  9. Organisation of autonomic nervous structures in the small intestine of chinchilla (Chinchilla laniger, Molina).

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    Nowak, E

    2014-08-01

    Using histochemical, histological and immunocytochemical methods, organisation of the autonomic nerve structures in small intestine of chinchilla was investigated. Myenteric plexus was localised between circular and longitudinal layers of the smooth muscles. Forming network nodes, the small autonomic, cholinergic ganglia were linked with the bundles of nerve fibres. Adrenergic structures were visible as specific varicose, rosary-like fibres forming bundles of parallel fibres connecting network nodes. Structures of the submucosal plexus formed a finer network than those of the myenteric plexus. Moreover, in 'whole-mount' specimens, fibres forming thick perivascular plexuses were also observed. Immunocytochemical studies confirmed the cholinergic and adrenergic character of the investigated structures. VAChT-positive neurones were found only in myenteric plexus, and numerous VAChT-positive and DBH-positive fibres were found in both plexuses.

  10. 3D finite element model of the chinchilla ear for characterizing middle ear functions.

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    Wang, Xuelin; Gan, Rong Z

    2016-10-01

    Chinchilla is a commonly used animal model for research of sound transmission through the ear. Experimental measurements of the middle ear transfer function in chinchillas have shown that the middle ear cavity greatly affects the tympanic membrane (TM) and stapes footplate (FP) displacements. However, there is no finite element (FE) model of the chinchilla ear available in the literature to characterize the middle ear functions with the anatomical features of the chinchilla ear. This paper reports a recently completed 3D FE model of the chinchilla ear based on X-ray micro-computed tomography images of a chinchilla bulla. The model consisted of the ear canal, TM, middle ear ossicles and suspensory ligaments, and the middle ear cavity. Two boundary conditions of the middle ear cavity wall were simulated in the model as the rigid structure and the partially flexible surface, and the acoustic-mechanical coupled analysis was conducted with these two conditions to characterize the middle ear function. The model results were compared with experimental measurements reported in the literature including the TM and FP displacements and the middle ear input admittance in chinchilla ear. An application of this model was presented to identify the acoustic role of the middle ear septa-a unique feature of chinchilla middle ear cavity. This study provides the first 3D FE model of the chinchilla ear for characterizing the middle ear functions through the acoustic-mechanical coupled FE analysis.

  11. Auditory cortex basal activity modulates cochlear responses in chinchillas.

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    Alex León

    Full Text Available BACKGROUND: The auditory efferent system has unique neuroanatomical pathways that connect the cerebral cortex with sensory receptor cells. Pyramidal neurons located in layers V and VI of the primary auditory cortex constitute descending projections to the thalamus, inferior colliculus, and even directly to the superior olivary complex and to the cochlear nucleus. Efferent pathways are connected to the cochlear receptor by the olivocochlear system, which innervates outer hair cells and auditory nerve fibers. The functional role of the cortico-olivocochlear efferent system remains debated. We hypothesized that auditory cortex basal activity modulates cochlear and auditory-nerve afferent responses through the efferent system. METHODOLOGY/PRINCIPAL FINDINGS: Cochlear microphonics (CM, auditory-nerve compound action potentials (CAP and auditory cortex evoked potentials (ACEP were recorded in twenty anesthetized chinchillas, before, during and after auditory cortex deactivation by two methods: lidocaine microinjections or cortical cooling with cryoloops. Auditory cortex deactivation induced a transient reduction in ACEP amplitudes in fifteen animals (deactivation experiments and a permanent reduction in five chinchillas (lesion experiments. We found significant changes in the amplitude of CM in both types of experiments, being the most common effect a CM decrease found in fifteen animals. Concomitantly to CM amplitude changes, we found CAP increases in seven chinchillas and CAP reductions in thirteen animals. Although ACEP amplitudes were completely recovered after ninety minutes in deactivation experiments, only partial recovery was observed in the magnitudes of cochlear responses. CONCLUSIONS/SIGNIFICANCE: These results show that blocking ongoing auditory cortex activity modulates CM and CAP responses, demonstrating that cortico-olivocochlear circuits regulate auditory nerve and cochlear responses through a basal efferent tone. The diversity of the

  12. Experimental otitis media in gerbils and chinchillas with Streptococcus pneumoniae, Haemophilus influenzae, and other aerobic and anaerobic bacteria.

    OpenAIRE

    Fulghum, R S; Brinn, J E; Smith, A M; Daniel, H J; Loesche, P J

    1982-01-01

    To ascertain the usefulness of Mongolian gerbils as an inbred model for otitis media, 52 Mongolian gerbils (Meriones unguiculatus, strain MONT/Tum) were compared with 26 chinchillas (Chinchilla laniger) for susceptibility to Streptococcus pneumoniae type 3. Haemophilus influenzae type b, and a polymicrobic culture including anaerobes (Streptococcus intermedius, Propionibacterium acnes, Staphylococcus epidermidis, and Corynebacterium sp.). Organisms were inoculated percutaneously into the supe...

  13. Influence of Selected Extenders for Liquid Storage at 4 degrees C of Breeding Chinchilla (Chinchilla lanigera) Semen on Sperm DNA Integrity.

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    Niedbała, Piotr; Szeleszczuk, Olga; Kuchta-Gładysz, Marta; Joneczek, Maria; Dobrzyńska, Małgorzata; Maj, Dorota

    2015-01-01

    The influence of two commercial and two laboratory oriented extenders on survival rate and DNA integrity of chinchilla (Chinchilla lanigera) sperm was determined during liquid storage. Semen was collected using an electroejaculator from 6 adult male chinchillas. Ejaculates (n = 16) were diluted with extenders to obtain a concentration of 40 x 10 (3) sperm/5 μl. After dilution the semen samples were stored at 4"C. The percent motility, progressive motility, and morphology were assessed conventionally, whereas DNA integrity was evaluated by Single Cell Gel Electrophoresis (comet) assay at 0 (just after dilution), 24, 48 and 72 h. Conventional assessment of sperm quality showed that commercial extenders are characterized by the lowest sperm survival parameters out of the investigated extenders. In commercial extenders spermatozoa lost their capacity for progressive motility compared to laboratory extenders. After 24 h storage, from 21.67% to 30% of motile sperms were observed in commercial extender whereas total sperm motility was 63.33% (41.67% with progressive motility) in samples in which stallion semen extender was used. After 72 h storage, 10% of sperm were motile in stallion semen extender while no sperm movement was observed in tubes containing the commercial extender. Furthermore, a lower percentage of damaged spermatozoa in laboratory oriented extenders was demonstrated. It was also stated that along with the extended time of semen storage at 4 degrees C, commercial extenders lost their protective action. An analysis of DNA content in the heads of sperm cells and tail moment (TM) showed that the most useful extender for liquid preservation of chinchilla semen was the extender for stallions.

  14. Non-invasive endocrine monitoring of ovarian and adrenal activity in chinchilla (Chinchilla lanigera) females during pregnancy, parturition and early post-partum period.

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    Mastromonaco, Gabriela F; Cantarelli, Verónica I; Galeano, María G; Bourguignon, Nadia S; Gilman, Christine; Ponzio, Marina F

    2015-03-01

    The chinchilla is a rodent that bears one of the finest and most valuable pelts in the world. The wild counterpart is, however, almost extinct because of a drastic past and ongoing population decline. The present work was developed to increase our knowledge of the reproductive physiology of pregnancy and post-partum estrus in the chinchilla, characterizing the endocrine patterns of urinary progesterone, estradiol, LH and cortisol metabolites throughout gestation and post-partum estrus and estimating the ovulation timing at post-partum estrus. Longitudinal urine samples were collected once per week throughout pregnancy and analyzed for creatinine, cortisol, LH, estrogen and progesterone metabolite concentrations. To indirectly determine the ovulation timing at post-partum estrus, a second experiment was performed using pregnant females subjected to a post-partum in vivo fertilization scheme. Urinary progestagen metabolites increased above baseline levels in early pregnancy between weeks-8 and -11 respectively to parturition, and slightly declined at parturition time. Urinary estrogens showed rising levels throughout mid- and late pregnancy (weeks-9 to -6 and a further increase at week-5 to parturition) and decreased in a stepwise manner after parturition, returning to baseline levels two weeks thereafter. Cortisol metabolite levels were relatively constant throughout pregnancy with a tendency for higher levels in the last third of gestation and after the pups' birth. Parturition was associated with dramatic reductions in urinary concentrations of sex steroids (especially progestagens). Observations in breeding farms indicated that the females that resulted in a second pregnancy after mating, did so on the second day after parturition. These data were in agreement with an LH peak detected 24h after parturition. Urinary steroid hormone patterns of estrogen and progestagen metabolites provided valuable information on endocrine events during pregnancy and after

  15. Analysis of an impulse response measured at the basilar membrane of the chinchilla (L)

    NARCIS (Netherlands)

    Wit, Hero P.; Bell, Andrew

    2015-01-01

    In a recent paper [J. Acoust. Soc. Am. 133, 2224-2239 (2013)], Shera and Cooper report on the impulse response of the basilar membrane (BM) of a chinchilla, a waveform which shows repetitive bursts. They explain the bursts in terms of repeated coherent reflection at BM discontinuities and partial re

  16. Wiener-kernel analysis of responses to noise of chinchilla auditory-nerve fibers

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    Recio-Spinoso, A; Temchin, AN; van Dijk, P; Fan, YH; Ruggero, MA

    2005-01-01

    Responses to broadband Gaussian white noise were recorded in auditory-nerve fibers of deeply anesthetized chinchillas and analyzed by computation of zeroth-, first-, and second-order Wiener kernels. The first- order kernels ( similar to reverse correlations or "revcors") of fibers with characteristi

  17. Conjuntivite bacteriana secundária à doença dentária em chinchilas (Chinchilla lanigera Bacterial conjunctivitis secondary to dental disease in chinchillas (Chinchilla lanigera

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    Ricardo Barbosa Lucena

    2012-11-01

    Full Text Available São relatados três casos de conjuntivite bacteriana associada à doença dentária grave em chinchilas. Todas as chinchilas afetadas tinham histórico de emagrecimento, hipersalivação e epífora, que progrediu para exsudação ocular purulenta. Durante a necropsia, foi constatado marcado alongamento da coroa clínica dos incisivos e molares, e crescimento do ápice dentário, causando deformação óssea e compressão do canal lacrimal. Histologicamente, observou-se infiltrado de neutrófilos na conjuntiva e pálpebras. Cultivo microbiológico do exsudato ocular revelou crescimento de Staphylococcus coagulase-positiva . Uma compressão do canal lacrimal pelo crescimento dentário excessivo impediu a drenagem das lágrimas, resultando em epífora. Esse é um importante fator predisponente para infecção bacteriana ocular em chinchilas.Three cases of bacterial conjunctivitis associated with severe dental disease in chinchillas are described. All affected chinchillas had a history of weight loss, ptyalism, and epiphora which progressed to suppurative ocular exsudation. At necropsy incisor and molar teeth revealed marked elongation of the clinical crown and overgrowth of the dental apexes resulting in deformation of the tear ducts. Histologically, there was neutrophilic infiltrate in the conjunctiva and eyelid skin. Microbiological culture carried out in samples from the ocular exsudate yielded Staphylococcus coagulase-positive. Compression of the lacrimal duct by dental overgrowth compromised tear draining and resulting in epiphora. This is a major predisposing factor inducing bacterial ocular infection in chinchillas.

  18. SLEEPING AND RESTING BEHAVIOR, FACTORS AND IMPLICATIONS IN BREEDING TECHNOLOGY OF CHINCHILLA

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    M. BOTHA

    2013-12-01

    Full Text Available Fallowing many papers, related to different breeding systems of the Chinchilla l., wirenetting floor and bedding cage, which results that there are no significant differencesoverview the growth indices and implicit the forage intake, we where studied thebreed’s behavior to explain all these. Adopting one of the breeding systems involvessmaller or bigger investment, this being the principal aim of this paper. Knowing thatChinchilla has an inactive period of 71,02% from 24 h, they are resting 54,05% and16,97% so-called sleeping in 24 h. From our studies results that most of inactive time(rest and sleeping they are sitting on the dust bath tray, no matter the floor type. Thatexplains there are no significant differences in outputs depending on the adoptedtechnology.

  19. Sex Difference in Susceptibility and Resistance to Noise-Induced Hearing Loss in Chinchillas

    Science.gov (United States)

    2000-10-01

    depletion of cellular GSH can increase sensitivity to damage. In organ culture, cisplatin has been shown to increase Superoxide dismutase (SOD...individually non-traumatic could combine to produce substantial hearing loss and hair cell damage in chinchillas. If cisplatin depletes GSH and other...compound that increases GSH and GSH -peroxidase activity, significantly reduced threshold shifts in rats treated with cisplatin , and Ravi et al

  20. Chinchilla laniger can be used as an experimental model for Taenia solium taeniasis.

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    Maravilla, Pablo; Garza-Rodriguez, Adriana; Gomez-Diaz, Benjamin; Jimenez-Gonzalez, Diego Emiliano; Toral-Bastida, Elizabeth; Martinez-Ocaña, Joel; West, Brett; Molina, Nadia; Garcia-Cortes, Ramon; Kawa-Karasik, Simon; Romero-Valdovinos, Mirza; Avila-Ramirez, Guillermina; Flisser, Ana

    2011-12-01

    Chinchilla laniger has been reported as an experimental definitive host for Taenia solium; however no information about its suitability and yield of gravid tapeworm proglottids containing viable and infective eggs has been published. In total 55 outbred female chinchillas were infected with 4 cysticerci each; hosts were immunodeppressed with 6 or 8 mg of methyl-prednisolone acetate every 14 days starting the day of infection and their discomfort was followed. Kinetics of coproantigen ELISA or expelled proglottids was used to define the infection status. Efficiency of tapeworm establishment was 21% and of parasite gravidity was 8%; chinchillas showed some degree of suffering along the infection. Viability of eggs obtained from gravid proglottids was tested comparing methods previously published, our results showed 62% viability with propidium iodide, 54% with trypan blue, 34% with neutral red, 30% by oncosphere activation and 7% with bromide 3-(4,5-dimetil-tiazol-2-il)-2,5-difenil-tetrazolio (MTT) reduction; no statistical differences were obtained between most techniques, except activation. Four piglets were infected with 50,000 eggs each, necropsy was performed 3 months later and, after counting the number of cysticerci recovered, the percentage of infection was similar to data obtained with T. solium eggs recovered from humans. Our results demonstrate that the experimental model of T. solium taeniasis in C. laniger is a good alternative for providing eggs and adult tapeworms to be used in different types of experiments; optimization of the model probably depends on the use of inbred hosts and on the reduction of infected animals' suffering.

  1. Use of the Chinchilla Model for Nasopharyngeal Colonization To Study Gene Expression by Moraxella catarrhalis

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    Hoopman, Todd C.; Liu, Wei; Joslin, Stephanie N.; Pybus, Christine; Sedillo, Jennifer L.; Labandeira-Rey, Maria; Laurence, Cassie A.; Wang, Wei; Richardson, James A.; Bakaletz, Lauren O.

    2012-01-01

    Young adult chinchillas were atraumatically inoculated with Moraxella catarrhalis via the nasal route. Detailed histopathologic examination of nasopharyngeal tissues isolated from these M. catarrhalis-infected animals revealed the presence of significant inflammation within the epithelium. Absence of similar histopathologic findings in sham-inoculated animals confirmed that M. catarrhalis was exposed to significant host-derived factors in this environment. Twenty-four hours after inoculation, viable M. catarrhalis organisms were recovered from the nasal cavity and nasopharynx of the animals in numbers sufficient for DNA microarray analysis. More than 100 M. catarrhalis genes were upregulated in vivo, including open reading frames (ORFs) encoding proteins that are involved in a truncated denitrification pathway or in the oxidative stress response, as well as several putative transcriptional regulators. Additionally, 200 M. catarrhalis genes were found to be downregulated when this bacterium was introduced into the nasopharynx. These downregulated genes included ORFs encoding several well-characterized M. catarrhalis surface proteins including Hag, McaP, and MchA1. Real-time reverse transcriptase PCR (RT-PCR) was utilized as a stringent control to validate the results of in vivo gene expression patterns as measured by DNA microarray analysis. Inactivation of one of the genes (MC ORF 1550) that was upregulated in vivo resulted in a decrease in the ability of M. catarrhalis to survive in the chinchilla nasopharynx over a 3-day period. This is the first evaluation of global transcriptome expression by M. catarrhalis cells in vivo. PMID:22184412

  2. Tone frequency maps and receptive fields in the developing chinchilla auditory cortex.

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    Pienkowski, Martin; Harrison, Robert V

    2005-01-01

    Single-unit responses to tone pip stimuli were isolated from numerous microelectrode penetrations of auditory cortex (under ketamine anesthesia) in the developing chinchilla (laniger), a precocious mammal. Results are reported at postnatal day 3 (P3), P15, and P30, and from adult animals. Hearing sensitivity and spike firing rates were mature in the youngest group. The topographic representation of sound frequency (tonotopic map) in primary and secondary auditory cortex was also well ordered and sharply tuned by P3. The spectral-temporal complexity of cortical receptive fields, on the other hand, increased progressively (past P30) to adulthood. The (purported) refinement of initially diffuse tonotopic projections to cortex thus seems to occur in utero in the chinchilla, where external (and maternal) sounds are considerably attenuated and might not contribute to the mechanism(s) involved. This compares well with recent studies of vision, suggesting that the refinement of the retinotopic map does not require external light, but rather waves of (correlated) spontaneous activity on the retina. In contrast, it is most probable that selectivity for more complex sound features, such as frequency stacks and glides, develops under the influence of the postnatal acoustic environment and that inadequate sound stimulation in early development (e.g., due to chronic middle ear disease) impairs the formation of the requisite intracortical (and/or subcortical) circuitry.

  3. Relación costo_beneficio en la termorregulación de Chinchilla lanigera Cost-benefit relationship in thermoregulation of Chinchilla lanigera

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    ARTURO CORTES

    2000-06-01

    Full Text Available Chinchilla lanigera, es un roedor endémico de Chile que habita áreas desérticas del norte de Chile. Postulamos que C. lanigera (silvestre por habitar en ambientes con escasa disponibilidad de alimento y agua, debiera poseer atributos fisiológicos que minimicen los requerimientos (costos de energía y agua. Se evaluó el metabolismo energético en atmósferas de aire y He-O2, la pérdida de agua por evaporación (EWL y temperatura corporal (Tb a diferentes temperaturas ambientales (Ta. Los resultados más relevantes muestran que la tasa metabólica basal (BMR fue 0,66 mlO2/g h y la conductancia térmica (C de 0,0376 mlO2/g h°C; valores que corresponden al 80,4% y 72,5% de la magnitud predicha para un mamífero euterio de similar tamaño corporal, respectivamente. La conductancia térmica en atmósfera He-O2 fue 0,089 mlO2/g h°C, siendo la razón C He-O2 /C = 0,089/0,038 = 2,34, el valor más alto descrito para roedores. Esto indicaría que C. lanigera, poseería la aislación térmica más alta documentada a la fecha. Además, la evaporación pulmocutánea (EWL equivale al 95% del valor esperado para heterómidos. Chinchilla lanigera presenta una clara relación de costo-beneficio y/o compromisos en su capacidad de termorregulación. En efecto, los bajos valores de C y EWL implican costos de termorregulación a altas temperaturas (riesgo de hipertermia, particularmente cuando su hábitat desértico alcanza temperaturas ž 30°C. A la vez, estos bajos valores de C, EWL y BMR constituyen beneficios fisiológicos que favorecen la economía de energía y agua en un hábitat que es xérico y poco productivoChinchilla lanigera, is an endemic rodent inhabiting desert areas of northern Chile. We postulated that wild chinchilla should has a cost-benefit relationship in thermoregulation to cope with desert habitats. We evaluated the energy metabolism in air and He-O2, evaporative water loss (EWL and body temperature (Tb at different ambient

  4. Reference values for chinchilla (Chinchilla laniger blood cells and serum biochemical parameters Valores de referência para os parâmetros das células e bioquímica sangüínea da chinchila (Chinchilla laniger

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    Tális de Oliveira Silva

    2005-06-01

    Full Text Available Raising chinchilla (Chinchilla laniger for commercial purpose has increased significantly; however, hematological and serum biochemical reference values have not yet been determined for chinchillas raised in south Brazil. Establishing blood cells and serum biochemistry reference values might be helpful to evaluate health status of chinchillas and might be used as a tool by clinicians. The purpose of this study was to determine the reference values for blood cells and serum biochemistry of Chinchilla laniger. Blood samples were collected by cardiac puncture from 16 adult males, at the time they were killed to remove the fur coat, and from 8 adult males anesthetized with ketamine and xylazine. Blood cell counts and serum biochemistry analysis were performed using standard techniques and the results were expressed as mean ± SEM. Analysis of blood parameters from post-mortem cardiac punctured and from anesthetized chinchillas indicated that blood samples from anesthetized chinchillas had higher PCV, Hemoglobin, MCHC and WBC (P A criação de chinchila (Chinchilla laniger com objetivos comerciais tem crescido muito nos últimos anos. No entanto, os valores de referência para os parâmetros hematológicos e bioquímicos não foram ainda determinados para chinchilas criados no sul do Brasil. O estabelecimento dos valores de referência para esses parâmetros pode servir de auxílio para a avaliação da saúde das chinchilas e servir de auxílio diagnóstico para o clínico. Esse estudo teve como objetivo determinar os valores de referência das células e da bioquímica sangüínea da Chinchilla laniger. As amostras de sangue foram coletadas por meio de punção cardíaca de 16 machos adultos no momento em que os animais foram mortos para remoção da pele, e de 8 machos adultos após anestesia com xylazina e ketamina. A contagem das células sangüíneas e a análise dos parâmetros bioquímicos foram feitas utilizando-se métodos padronizados em

  5. Experimental otitis media in gerbils and chinchillas with Streptococcus pneumoniae, Haemophilus influenzae, and other aerobic and anaerobic bacteria.

    Science.gov (United States)

    Fulghum, R S; Brinn, J E; Smith, A M; Daniel, H J; Loesche, P J

    1982-05-01

    To ascertain the usefulness of Mongolian gerbils as an inbred model for otitis media, 52 Mongolian gerbils (Meriones unguiculatus, strain MONT/Tum) were compared with 26 chinchillas (Chinchilla laniger) for susceptibility to Streptococcus pneumoniae type 3. Haemophilus influenzae type b, and a polymicrobic culture including anaerobes (Streptococcus intermedius, Propionibacterium acnes, Staphylococcus epidermidis, and Corynebacterium sp.). Organisms were inoculated percutaneously into the superior chamber of the middle ear bulla. The gerbils and chinchillas shared similar susceptibilities and responses to the inoculated organisms as determined by X-ray, otoscopic, histopathological, and microbiological determinations at 5 to 7 days. Koch's postulate studies proved the role of S. pneumoniae and H. influenzae in the pathology found in both animal models. The animals were also susceptible to the polymicrobic culture, although the relative virulence of the individual members of this mixture was low, suggesting that these species potentiated as a polymicrobic mixture. The Corynebacterium sp. appeared to elicit the greatest histopathological response in chronic (8-week) studies in gerbils. The gerbils were found to be useful as an alternative animal model for the study of otitis media of bacterial etiology.

  6. Surto de listeriose sistêmica em chinchilas Outbreak of systemic listeriosis in chinchillas

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    Jackeline Karsten Kirinus

    2010-03-01

    Full Text Available A listeriose é uma doença infecciosa que afeta uma grande variedade de espécies animais, causando septicemia, encefalite e aborto. As chinchilas são os animais mais susceptíveis à infecção sistêmica por Listeria monocytogenes. Este relato descreve um surto de listeriose sistêmica em uma criação de chinchilas da região central do Estado do Rio Grande do Sul, onde cerca de 16% das chinchilas morreram. Na necropsia, havia múltiplos focos brancos, pequenos e de distribuição aleatória nas superfícies capsular e de corte do fígado e aumento de volume do linfonodo hepático. Histologicamente, observaram-se hepatite necrossupurativa e linfadenite supurativa multifocais, com numerosos bacilos intralesionais. L. monocytogenes foi o agente etiológico do surto de listeriose sistêmica, sendo o diagnóstico confirmado por meio das lesões de necropsia e histopatológicas, das características fenotípicas e genotípicas da bactéria e da técnica de imuno-histoquímica.Listeriosis is an infectious disease, which affects a variety of animal species and cause septicemia, encephalitis and abortion. Chinchillas are the most susceptible animals to the systemic infection by Listeria monocytogenes. This report describes an outbreak of systemic listeriosis in a farm of chinchillas in the Central region of the Rio Grande do Sul state, Brazil. Mortality rate was about 16%. On necropsy, there were multiple random small white foci on the liver capsule and parenchyma and enlargement of the hepatic lymph node. Histologically, there were multifocal necro-suppurative hepatitis and suppurative lymphadenitis with numerous intralesional bacilli. L. monocytogenes was the etiology of the systemic listeriosis outbreak. The diagnosis was based on gross and microscopic lesions, genotypical and phenotypical characteristics and by immunohistochemistry technique.

  7. Effects of intratympanic gentamicin on vestibular afferents and hair cells in the chinchilla.

    Science.gov (United States)

    Hirvonen, Timo P; Minor, Lloyd B; Hullar, Timothy E; Carey, John P

    2005-02-01

    Gentamicin is toxic to vestibular hair cells, but its effects on vestibular afferents have not been defined. We treated anesthetized chinchillas with one injection of gentamicin (26.7 mg/ml) into the middle ear and made extracellular recordings from afferents after 5-25 (early) or 90-115 days (late). The relative proportions of regular, intermediate, and irregular afferents did not change after treatment. The spontaneous firing rate of regular afferents was lower (P galvanic currents was unaffected for all afferents. Intratympanic gentamicin treatment reduced the histological density of all hair cells by 57% (P = 0.04). The density of hair cells with calyx endings was reduced by 99% (P = 0.03), although some remaining hair cells had other features suggestive of type I morphology. Type II hair cell density was not significantly reduced. These findings suggest that a single intratympanic gentamicin injection causes partial damage and loss of vestibular hair cells, particularly type I hair cells or their calyceal afferent endings, does not damage the afferent spike initiation zones, and preserves enough hair cell synaptic activity to drive the spontaneous activity of vestibular afferents.

  8. A functional tonB gene is required for both virulence and competitive fitness in a chinchilla model of Haemophilus influenzae otitis media

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    Morton Daniel J

    2012-06-01

    Full Text Available Abstract Background Haemophilus influenzae requires heme for aerobic growth and possesses multiple mechanisms to obtain this essential nutrient. Methods An insertional mutation in tonB was constructed and the impact of the mutation on virulence and fitness in a chinchilla model of otitis media was determined. The tonB insertion mutant strain was significantly impacted in both virulence and fitness as compared to the wildtype strain in this model. Conclusions The tonB gene of H. influenzae is required for the establishment and maintenance of middle ear infection in this chinchilla model of bacterial disease.

  9. Auditory brainstem responses predict auditory nerve fiber thresholds and frequency selectivity in hearing impaired chinchillas.

    Science.gov (United States)

    Henry, Kenneth S; Kale, Sushrut; Scheidt, Ryan E; Heinz, Michael G

    2011-10-01

    Noninvasive auditory brainstem responses (ABRs) are commonly used to assess cochlear pathology in both clinical and research environments. In the current study, we evaluated the relationship between ABR characteristics and more direct measures of cochlear function. We recorded ABRs and auditory nerve (AN) single-unit responses in seven chinchillas with noise-induced hearing loss. ABRs were recorded for 1-8 kHz tone burst stimuli both before and several weeks after 4 h of exposure to a 115 dB SPL, 50 Hz band of noise with a center frequency of 2 kHz. Shifts in ABR characteristics (threshold, wave I amplitude, and wave I latency) following hearing loss were compared to AN-fiber tuning curve properties (threshold and frequency selectivity) in the same animals. As expected, noise exposure generally resulted in an increase in ABR threshold and decrease in wave I amplitude at equal SPL. Wave I amplitude at equal sensation level (SL), however, was similar before and after noise exposure. In addition, noise exposure resulted in decreases in ABR wave I latency at equal SL and, to a lesser extent, at equal SPL. The shifts in ABR characteristics were significantly related to AN-fiber tuning curve properties in the same animal at the same frequency. Larger shifts in ABR thresholds and ABR wave I amplitude at equal SPL were associated with greater AN threshold elevation. Larger reductions in ABR wave I latency at equal SL, on the other hand, were associated with greater loss of AN frequency selectivity. This result is consistent with linear systems theory, which predicts shorter time delays for broader peripheral frequency tuning. Taken together with other studies, our results affirm that ABR thresholds and wave I amplitude provide useful estimates of cochlear sensitivity. Furthermore, comparisons of ABR wave I latency to normative data at the same SL may prove useful for detecting and characterizing loss of cochlear frequency selectivity.

  10. Stimulus Frequency Otoacoustic Emission Delays and Generating Mechanisms in Guinea Pigs, Chinchillas, and Simulations.

    Science.gov (United States)

    Berezina-Greene, Maria A; Guinan, John J

    2015-12-01

    According to coherent reflection theory (CRT), stimulus frequency otoacoustic emissions (SFOAEs) arise from cochlear irregularities coherently reflecting energy from basilar membrane motion within the traveling-wave peak. This reflected energy arrives in the ear canal predominantly with a single delay at each frequency. However, data from humans and animals indicate that (1) SFOAEs can have multiple delay components, (2) low-frequency SFOAE delays are too short to be accounted for by CRT, and (3) "SFOAEs" obtained with a 2nd ("suppressor") tone ≥2 octaves above the probe tone have been interpreted as arising from the area basal to the region of cochlear amplification. To explore these issues, we collected SFOAEs by the suppression method in guinea pigs and time-frequency analyzed these data, simulated SFOAEs, and published chinchilla SFOAEs. Time-frequency analysis revealed that most frequencies showed only one SFOAE delay component while other frequencies had multiple components including some with short delays. We found no systematic patterns in the occurrence of multiple delay components. Using a cochlear model that had significant basilar membrane motion only in the peak region of the traveling wave, simulated SFOAEs had single and multiple delay components similar to the animal SFOAEs. This result indicates that multiple components (including ones with short delays) can originate from cochlear mechanical irregularities in the SFOAE peak region and are not necessarily indicative of SFOAE sources in regions ≥2 octaves basal of the SFOAE peak region. We conclude that SFOAEs obtained with suppressors close to the probe frequency provide information primarily about the mechanical response in the region that receives amplification, and we attribute the too-short SFOAE delays at low frequencies to distortion-source SFOAEs and coherent reflection from multiple cochlear motions. Our findings suggest that CRT needs revision to include reflections from multiple

  11. Wiener kernels of chinchilla auditory-nerve fibers : Verification using responses to tones, clicks, and noise and comparison with basilar-membrane vibrations

    NARCIS (Netherlands)

    Temchin, AN; Recio-Spinoso, A; van Dijk, P; Ruggero, MA

    2005-01-01

    Responses to tones, clicks, and noise were recorded from chinchilla auditory-nerve fibers (ANFs). The responses to noise were analyzed by computing the zeroth-, first-, and second-order Wiener kernels (h(0), h(1), and h(2)). The h(1) s correctly predicted the frequency tuning and phases of responses

  12. Transfection using hydroxyapatite nanoparticles in the inner ear via an intact round window membrane in chinchilla

    Energy Technology Data Exchange (ETDEWEB)

    Wu Xuewen; Ding Dalian [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Jiang Haiyan [State University of New York at Buffalo, Center for Hearing and Deafness (United States); XingXiaowei [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Huang, Suping [Central South University, State Key Laboratory of Powder Metallurgy (China); Liu Hong [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Chen Zhedong [Central South University, State Key Laboratory of Powder Metallurgy (China); Sun Hong, E-mail: shjhaj@vip.163.com [Central South University, Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital (China)

    2012-01-15

    Hydroxyapatite nanoparticles (nHAT) are known to have excellent biocompatibility, and have attracted increasing attention as new candidates of non-viral vectors for gene therapy. In our previous studies, nHAT carrying a therapeutic gene and a reporter gene were successfully transfected into the spiral ganglion neurons in the inner ear of guinea pigs in vivo as well as in the cultured cell lines, although the transfection efficiencies were never higher than 30%. In this study, the surface modification of nHAT with polyethylenimine (PEI) was made (PEI-nHAT, diameter = 73.09 {+-} 27.32 nm) and a recombinant plasmid carrying enhanced green fluorescent protein (EGFP) gene and neurotrophin-3 (NT-3) gene was constructed as pEGFPC2-NT3. The PEI modified nHAT and the recombinant plasmid was then connected to form the nHAT-based vector-gene complex (PEI-nHAT-pEGFPC2-NT3). This complex was then placed onto the intact round window membranes of the chinchillas for inner ear transfection. Auditory brainstem response (ABR) was tested to evaluate auditory function. Green fluorescence of EGFP was observed using confocal microscopy 48 h after administering vector-gene complexes. There was no significant threshold shift in tone burst-evoked ABR at any tested frequency. Abundant, condensed green fluorescence was found in dark cells on both sides of the crista and around the macula of the utricle. Scattered EGFP signals were also detected in vestibular hair cells, some Schwann cells in the cochlear spiral ganglion region, some outer pillar cells in the organ of Corti, and a few cells in the stria vascularis. The density of green fluorescence-marked cells was obviously higher in the vestibular dark cell area than in other areas of the inner ear, suggesting that vestibular dark cells may have the ability to actively engulf the nHAT-based vector-gene complexes. Considering the high transfection efficiency in the vestibular system, PEI-nHAT may be a potential vector for gene therapy of

  13. Transfection using hydroxyapatite nanoparticles in the inner ear via an intact round window membrane in chinchilla

    Science.gov (United States)

    Wu, Xuewen; Ding, Dalian; Jiang, Haiyan; Xing, Xiaowei; Huang, Suping; Liu, Hong; Chen, Zhedong; Sun, Hong

    2012-01-01

    Hydroxyapatite nanoparticles (nHAT) are known to have excellent biocompatibility, and have attracted increasing attention as new candidates of non-viral vectors for gene therapy. In our previous studies, nHAT carrying a therapeutic gene and a reporter gene were successfully transfected into the spiral ganglion neurons in the inner ear of guinea pigs in vivo as well as in the cultured cell lines, although the transfection efficiencies were never higher than 30%. In this study, the surface modification of nHAT with polyethylenimine (PEI) was made (PEI-nHAT, diameter = 73.09 ± 27.32 nm) and a recombinant plasmid carrying enhanced green fluorescent protein (EGFP) gene and neurotrophin-3 (NT-3) gene was constructed as pEGFPC2-NT3. The PEI modified nHAT and the recombinant plasmid was then connected to form the nHAT-based vector-gene complex (PEI-nHAT-pEGFPC2-NT3). This complex was then placed onto the intact round window membranes of the chinchillas for inner ear transfection. Auditory brainstem response (ABR) was tested to evaluate auditory function. Green fluorescence of EGFP was observed using confocal microscopy 48 h after administering vector-gene complexes. There was no significant threshold shift in tone burst-evoked ABR at any tested frequency. Abundant, condensed green fluorescence was found in dark cells on both sides of the crista and around the macula of the utricle. Scattered EGFP signals were also detected in vestibular hair cells, some Schwann cells in the cochlear spiral ganglion region, some outer pillar cells in the organ of Corti, and a few cells in the stria vascularis. The density of green fluorescence-marked cells was obviously higher in the vestibular dark cell area than in other areas of the inner ear, suggesting that vestibular dark cells may have the ability to actively engulf the nHAT-based vector-gene complexes. Considering the high transfection efficiency in the vestibular system, PEI-nHAT may be a potential vector for gene therapy of inner

  14. Strain-specific virulence phenotypes of Streptococcus pneumoniae assessed using the Chinchilla laniger model of otitis media.

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    Michael L Forbes

    Full Text Available BACKGROUND: Streptococcus pneumoniae [Sp] infection is associated with local and systemic disease. Our current understanding of the differential contributions of genetic strain variation, serotype, and host response to disease phenotype is incomplete. Using the chinchilla model of otitis media [OM] we investigated the disease phenotype generated by the laboratory strain TIGR4 and each of thirteen clinical strains (BS68-75, BS290, BS291, BS293, BS436 and BS437; eleven of the thirteen strains have been genomically sequenced. METHODOLOGY/PRINCIPAL FINDINGS: For each strain 100 colony forming units were injected bilaterally into the tympanic bullae of 6 young adult chinchillas under general anesthesia. All animals were examined daily for local and systemic disease by a blinded observer. Pneumatic otoscopy was used to evaluate local disease, and behavioral assessments served as the measure of systemic disease. Virulence scoring was performed using a 4-point scale to assess four clinical parameters [severity and rapidity of local disease onset; and severity and rapidity of systemic disease onset] during a 10-day evaluation period. Highly significant variation was observed among the strains in their ability to cause disease and moribundity. CONCLUSIONS/SIGNIFICANCE: As expected, there was a significant correlation between the rapidity of systemic disease onset and severity of systemic disease; however, there was little correlation between the severity of otoscopic changes and severity of systemic disease. Importantly, it was observed that different strains of the same serotype produced as broad an array of disease phenotypes as did strains of different serotypes. We attribute these phenotypic differences among the strains to the high degree of genomic plasticity that we have previously documented.

  15. COMPARATIVE RESEARCHE REGARDING METABOLIC PROFILE OF THE CALIFORNIAN, NEW ZEALAND WHITE, GRAND CHINCHILLA MEAT RABIT BREEDS AND THE F1 NZCH HYBRIDS

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    DANIELA-MARCELA TOBĂ (GOINA

    2013-12-01

    Full Text Available Precious biological characteristics of rabbits make their breeding a very profitable occupation. The rabbit meat, organoleptically same to the white meat, is rich in proteins, but low in fats. Biological researched done in direction to elucidate the biochemical systems that are the basis for organism physiological processes, have revealed that the level in which this process are develop directly influence the rabbits productivity capacity. 60 rabbit’s heads was used as biological material, distributed in: 15 Californian, 15 New Zeeland White, 15 Grand Chinchilla and 15 F1NZCH hybrids obtained from cross-breeding the New Zeeland White as maternal form and Grand Chinchilla as paternal form. Blood was sampled from the rabbit and was biochemical analyzed. The studied indices were: total protein, albumin, urea, uric acid, creatinine, total bilirubine, cholesterol, triglyceride and glucose. The experimental lot formed from F1 NZCH hybrids registered a concentration of 2.1 mg/dl uric acid, and in the other three lots the concentration was under 2 mg/dl. In all four lots, uric acid value was in normal limits. The determined creatinine registered very low values, under 1 mg/dl, at the low limit of reference values. At hybrids from New Zeeland White as maternal form and Grand Chinchilla as paternal form, in equal environmental conditions, the serum biochemical analysis haven’t registered significant differences compared to pure breeds individuals.

  16. Chronic stimulation of the semicircular canals using a multichannel vestibular prosthesis: effects on locomotion and angular vestibulo-ocular reflex in chinchillas.

    Science.gov (United States)

    Sun, Daniel Q; Rahman, Mehdi A; Fridman, Gene; Dai, Chenkai; Chiang, Bryce; Della Santina, Charles C

    2011-01-01

    Bilateral loss of vestibular sensation causes difficulty maintaining stable vision, posture and gait. An implantable prosthesis that partly restores vestibular sensation could significantly improve quality of life for individuals disabled by this disorder. We have developed a head-mounted multichannel vestibular prosthesis (MVP) that restores sufficient semicircular canal function to recreate a 3D angular vestibulo-ocular reflex (aVOR). In this study, we evaluated effects of chronic MVP stimulation on locomotion in chinchillas. Two of three animals examined exhibited significant improvements in both locomotion and aVOR.

  17. A member of the cathelicidin family of antimicrobial peptides is produced in the upper airway of the chinchilla and its mRNA expression is altered by common viral and bacterial co-pathogens of otitis media.

    Science.gov (United States)

    McGillivary, Glen; Ray, William C; Bevins, Charles L; Munson, Robert S; Bakaletz, Lauren O

    2007-03-01

    Cationic antimicrobial peptides (AMPs), a component of the innate immune system, play a major role in defense of mucosal surfaces against a wide spectrum of microorganisms such as viral and bacterial co-pathogens of the polymicrobial disease otitis media (OM). To further understand the role of AMPs in OM, we cloned a cDNA encoding a cathelicidin homolog (cCRAMP) from upper respiratory tract (URT) mucosae of the chinchilla, the predominant host used to model experimental OM. Recombinant cCRAMP exhibited alpha-helical secondary structure and killed the three main bacterial pathogens of OM. In situ hybridization showed cCRAMP mRNA production in epithelium of the chinchilla Eustachian tube and RT-PCR was used to amplify cCRAMP mRNA from several other tissues of the chinchilla URT. Quantitative RT-PCR analysis of chinchilla middle ear epithelial cells (CMEEs) incubated with either viral (influenza A virus, adenovirus, or RSV) or bacterial (nontypeable H. influenzae, M. catarrhalis, or S. pneumoniae) pathogens associated with OM demonstrated distinct microbe-specific patterns of altered expression. Collectively, these data showed that viruses and bacteria modulate AMP messages in the URT, which likely contributes to the disease course of OM.

  18. Virulence phenotypes of low-passage clinical isolates of Nontypeable Haemophilus influenzae assessed using the chinchilla laniger model of otitis media

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    Hogg Justin

    2007-06-01

    Full Text Available Abstract Background The nontypeable Haemophilus influenzae (NTHi are associated with a spectrum of respiratory mucosal infections including: acute otitis media (AOM; chronic otitis media with effusion (COME; otorrhea; locally invasive diseases such as mastoiditis; as well as a range of systemic disease states, suggesting a wide range of virulence phenotypes. Genomic studies have demonstrated that each clinical strain contains a unique genic distribution from a population-based supragenome, the distributed genome hypothesis. These diverse clinical and genotypic findings suggest that each NTHi strain possesses a unique set of virulence factors that contributes to the course of the disease. Results The local and systemic virulence patterns of ten genomically characterized low-passage clinical NTHi strains (PittAA – PittJJ obtained from children with COME or otorrhea were stratified using the chinchilla model of otitis media (OM. Each isolate was used to bilaterally inoculate six animals and thereafter clinical assessments were carried out daily for 8 days by blinded observers. There was no statistical difference in the time it took for any of the 10 NTHi strains to induce otologic (local disease with respect to any or all of the other strains, however the differences in time to maximal local disease and the severity of local disease were both significant between the strains. Parameters of systemic disease indicated that the strains were not all equivalent: time to development of the systemic disease, maximal systemic scores and mortality were all statistically different among the strains. PittGG induced 100% mortality while PittBB, PittCC, and PittEE produced no mortality. Overall Pitt GG, PittII, and Pitt FF produced the most rapid and most severe local and systemic disease. A post hoc determination of the clinical origins of the 10 NTHi strains revealed that these three strains were of otorrheic origin, whereas the other 7 were from patients

  19. Caracterización litogeoquímica del granito La Chinchilla y su relación con el uranio, siella de Velasco, provincia de La Rioja

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    Marcos Salvatore

    2013-09-01

    Full Text Available El plutón La Chinchilla es un cuerpo granítico de forma subelipsoidal en planta que aflora en el sector central de la sierra de Velasco, provincia de La Rioja, Argentina, cubriendo un área aproximada de 3,75 km2. Intruye en forma neta al granito porfírico Huaco, o bien mediante contactos pegmatoides y en algunos sectores con desarrollo de stockscheider. Fueron definidas tres facies graníticas en base a sus características texturales, composición mineralógica y radioactividad natural. La facies porfírica de mayor extensión areal, la facies equigranular y la facies de borde de grano fino de escasa representación areal, todas correspondientes modalmente a monzogranitos. Los análisis químicos reflejan contenidos elevados en uranio para todas las facies, siendo la equigranular la que muestra los mayores tenores. Asimismo esta facies se encuentra levemente enriquecida en álcalis, elementos incompatibles (F, Rb, Sn y U y relaciones Th/U menores a 0,8 evidenciando un mayor grado de fraccionamiento.

  20. 卡铂对灰鼠中枢听觉系统的影响%Carboplatin results in neuron loss in the cochlear nucleus but not the inferior colliculus or auditory cortex of chinchilla

    Institute of Scientific and Technical Information of China (English)

    孙建和; 杨伟炎; 丁大连; 孙伟; Sandra McFadden; Richard Salvi

    2003-01-01

    Objective Carboplatin selectively destroys inner hair cells (IHC)and typeⅠspiral ganglion neurons in the chinchilla cochlea;however,its effects on the central auditory system are largely unknown.The aim of this study was to determine if carboplatin treatment affects neuron survival in the cochlear nucleus (CN),inferior colliculus(IC)or auditory cortex(AC)of the chinchilla.Methods Chinchillas were treated with carboplatin(100mg/kg IP).Three weeks later,they were sacrificed and perfused intracardially with fixative.Surface preparations of Corti's organ were analyzed for hair cell loss.Serial frozen sections taken from the CN, IC and AC were stained with toluidine blue,and neurons were counted in representative sections from two normal(control)and four carboplatin-treated chinchillas. Results The results showed that carboplatin destroyed approximately 80% of the IHC,but almost none of the outer hair cells (OHC). In the central auditory system, carboplatin resulted in a significant loss of neurons in the anteroventral, posteroventral and dorsal divisions of the CN, but not in the IC or AC. Conclusionon Future studies will determine if the loss of neurons in the CN is a direct result of carboplatin neurotoxicity or a secondary effect of inner hair cell and spiral ganglion neuron loss in the auditory periphery.%目的卡铂选择性破坏灰鼠的内毛细胞和Ⅰ型传入神经末梢已被人们所证实,但是,卡铂是否损害耳蜗核、下丘和听觉皮层还不清楚,本文旨在观察卡铂对灰鼠听觉中枢的毒性作用.方法采用恒低温冷冻连续脑组织切片,以中枢听觉系统神经元的密度来评价卡铂对灰鼠中枢听觉系统的影响.结果发现注射卡铂3和4周后,耳蜗背侧核和腹侧核神经元明显的减少,与正常动物比较有显著性差异.而下丘和听觉皮层神经元的变化与正常灰鼠比较无明显差异.结论说明注射卡铂3和4周后对耳蜗核有明显的毒性作用,可引起耳蜗核神

  1. Correlation between reduction of distortion product otoacoustic emission and percentage of outer hair cell missing in chinchillas%灰鼠畸变产物耳声发射改变和外毛细胞缺失程度的相关分析

    Institute of Scientific and Technical Information of China (English)

    于栋祯; 丁大连; 殷善开; Richard J Salvi

    2009-01-01

    目的 探讨灰鼠畸变产物耳声发射(DPOAE)幅值的降低与外毛细胞缺失率之间的关系.方法 联合应用顺铂和利尿酸钠,建立灰鼠耳蜗毛细胞损伤模型.12只灰鼠在静脉注射利尿酸钠(40 mg/kg)同时,腹腔注射顺铂(0.2 mg/kg),分别于用药前和用药后的1周、2周及3周在清醒状态下检测动物DPOAE,并在施行最后1次DPOAE检测后处死动物.常规制备灰鼠耳蜗基底膜铺片并进行全耳蜗毛细胞计数.计算用药前和处死前DPOAE幅值的改变程度,通过Pearson相关分析对DPOAE幅值的降低与外毛细胞缺失程度之间的相关性进行分析.结果 顺铂和利尿酸钠引起灰鼠耳蜗外毛细胞缺失的特点是病变始发于基底膜的底回并逐渐向顶回发展,外毛细胞的缺损程度沿着基底膜从底回向顶回逐渐减轻,而不同频率DPOAE幅值降低的程度亦遵循从高频向低频发展的规律,各频率DPOAE在注射顺铂和利尿酸钠后的幅值改变与基底膜上相应部位的外毛细胞缺损程度存在一定的对应关系(r=0.796,P<0.05).外毛细胞每损失1%,可引起约0.24 dB的DPOAE幅值降低.结论 在灰鼠耳蜗损伤模型中,从DPOAE幅值的变化可以大致评估耳蜗外毛细胞的缺失程度.%Objective To explore the quantitative relationship between the reduction of distortion product otoacoustic emission (DPOAE) and the percentage of outer hair cell loss. Methods Coadministration of cisplatin (0.2 mg/kg) and ethacrynic acid (40 mg/kg) were used to estabhsh a cochlear lesion model in chinchillas. DPOAE was measured before and 1 week, 2 weeks, and 3 weeks later respectively after cisplatin and ethacrynic acid treatment. Animals were terminated 3 weeks after the treatment. Cochlear surface preparations were performed, and the cochlear hair cells were counted through entire length of the cochlea. The correlation between DPOAE reduction and outer hair cell missing was analyzed using Pearson correlation analysis

  2. Doenças de chinchilas (Chinchilla lanigera

    Directory of Open Access Journals (Sweden)

    Ricardo B. Lucena

    2012-06-01

    Full Text Available As doenças de chinchilas foram estudadas através da avaliação de laudos de necropsia entre janeiro de 1997 e dezembro de 2011. Em 202 chinchilas necropsiadas, 189 (93,5% tiveram o diagnóstico determinado, e 13 (6,5% tiveram diagnóstico inconclusivo, por ausência de lesões ou autólise acentuada. Dentre as 202 chinchilas computadas, 162 eram fêmeas (80%, 37 eram machos (18%, e em quatro chinchilas (2% o sexo não foi anotado. As chinchilas tinham entre um dia a 12 anos de idade. As doenças foram agrupadas nas seguintes categorias: doenças inflamatórias, doenças causadas por intoxicações, doenças causadas por agentes físicos, doenças metabólicas, doenças parasitárias, doenças degenerativas, distúrbios circulatórios, neoplasmas, distúrbios do desenvolvimento e "outros distúrbios". As doenças inflamatórias foram as mais prevalentes (52 casos [25,7%] e foram representadas por casos de gastrite (10 casos, listeriose (5 casos, septicemia (5 casos, broncopneumonia bacteriana (4 casos, enterite necrosante (4 casos, piometra (4 casos, diarreia com isolamento de Proteus sp. (3 casos, abscessos subcutâneos e em linfonodos (2 casos, endometrite (2 casos, otite (2 casos, pielonefrite (2 casos, abscesso do ligamento redondo do fígado (1 caso, pneumonia fibrinosa (1 caso, pneumonia intersticial (1 caso, hepatite e colecistite com isolamento de Salmonella sp. (1 caso, histiocitose pulmonar (1 caso, miosite linfo-histiocítica (1 caso e um caso de dermatofitose (Trichopyton metagrophytes. O segundo grupo de doenças mais prevalentes foram as intoxicações (22,3%, representado por 45 casos de intoxicação por salinomicina. As doenças causadas por agentes físicos (21 casos [10,4%] incluíam casos de traumas causados por outros animais (8 casos, automutilação após injeção intramuscular (8 casos, prolapso de reto (3 casos e parto distócico (2 casos. A categoria de doenças metabólicas foi representada por 16 casos (7,9% de lipidose hepática. As doenças parasitárias (8 casos [4%] consistiram em infestação por pulga (4 casos, piolho (3 casos e giardíase (1 caso. Doenças degenerativas (4 casos [2,5%] incluíam insuficiência renal crônica (2 casos, necrose aleatória de hepatócitos (1 caso e necrose muscular de origem desconhecida (1 caso. Os distúrbios circulatórios incluíram dois casos (0,99% de insuficiência cardíaca congestiva. Neoplasmas foram representados por dois casos (0,99% de adenocarcinoma gástrico. Um caso de atresia ani, associado a ausência do trato reprodutor, intestino grosso e rins policíticos representou a categoria de distúrbios do desenvolvimento (0,5%. Algumas doenças não se enquadraram nas categorias acima e foram enquadradas em "outros distúrbios" (38 casos [18,8%]. Nesta categoria, doenças dentárias foi o distúrbio mais comum, diagnosticado em 9% (18 de 202 de todas as chinchilas examinadas. Seguido por casos de hipertermia (14 casos, dois casos de anemia, dois casos de metaplasia de células adiposas do córtex da adrenal, e dois casos de mucometra.

  3. Infecção sistêmica por Yersinia enterocolitica em chinchilas (Chinchilla laniger

    Directory of Open Access Journals (Sweden)

    Luciana Sonne

    2012-05-01

    Full Text Available Yersinia enterocolitica é uma bactéria Gram-negativa que causa infecções em diversas espécies de mamíferos. O agente, geralmente, provoca infecções restritas ao intestino e linfonodos mesentéricos, porém a infecção pode se tornar sistêmica ocasionando lesões em outros órgãos como fígado e baço. Neste trabalho descrevem-se dois surtos de infecções sistêmicas causadas pela Yersinia enterocolitica em criatórios comerciais de chinchilas no Rio Grande do Sul (Brasil. Os proprietários relatavam que os animais acometidos apresentavam apatia, anorexia e morte. Foram encaminhados 13 animais para a realização de necropsia. No exame post mortem dos animais observou-se esplenomegalia, hepatomegalia e áreas multifocais esbranquiçadas no fígado, baço, pulmões, rins e intestino. No exame microscópico visualizou-se infiltrado inflamatório de neutrófilos e macrófagos, necrose, deposição de fibrina e ocasionalmente pode ser observado coco-bacilos no centro das áreas de necrose. No cultivo bacteriológico obteve-se o crescimento de Yersinia enterocolitica nos animais provenientes dos dois criatórios. O agente foi isolado de amostras no fígado, baço, intestino e pulmões dos animais necropsiados, além do cultivo de fezes de animais de uma das propriedades acometidas. A yersiniose, portanto, é uma patologia que deve ser investigada em casos de mortalidade de chinchilas.

  4. Effects of moderate-level sound exposure on behavioral thresholds in chinchillas

    OpenAIRE

    Carbajal de Nava, Maria Sandra

    2015-01-01

    Normal audiometric thresholds following noise exposure have generally been considered as an indication of a recovered cochlea and intact peripheral auditory system, yet recent animal work has challenged this classic assumption. Moderately noise-exposed animals have been shown to have permanent loss of synapses on inner hair cells (IHCs) and permanent damage to auditory nerve fibers (ANFs), specifically the low-spontaneous rate fibers (low-SR), despite normal electrophysiological thresholds. L...

  5. Surtos de intoxicação por salinomicina em chinchilas (Chinchilla lanigera

    Directory of Open Access Journals (Sweden)

    Ricardo B. Lucena

    2012-01-01

    Full Text Available Quatro surtos de intoxicação por salinomicina são descrito em chinchilas de três municípios do Estado do Rio Grande do Sul. Uma semana após a ingestão de ração contendo 37 ppm de salinomicina, aproximadamente duas mil chinchilas de quatro fazendas expostas diminuíram o consumo da ração. Quatrocentos e vinte sete chinchilas demonstraram apatia. Dessas, duzentos e setenta e sete desenvolveram decúbito esternal e lateral, dispneia e coma, seguidos de morte. As primeiras mortes ocorreram oito dias após a ingestão da ração. A evolução dos sinais clínicos até a morte ou eutanásia foi de 2-5 dias. Os exames bioquímicos do soro sanguíneo em quatro chinchilas revelaram níveis aumentados da alanina aminotransferase, aspartato transaminase, fosfatase alcalina, creatina cinase, glicose, triglicerídeos e colesterol total. Quarenta e cinco chinchilas foram submetidas à necropsia. Os achados macroscópicos consistiam de marcada lipidose hepática em todas as chinchilas necropsiadas; fetos em estado de decomposição em doze chinchilas que estavam prenhes. Microscopicamente, múltiplas fibras musculares esqueléticas estavam hipereosinofílicas, tumefeitas e com perda das estriações. Nas chinchilas que sobreviveram por mais dias era possível observar segmentos fragmentados de miofibras afetadas (necrose flocular e regeneração de miofibras. No fígado foi observada marcada degeneração gordurosa. Não foram observadas anormalidades microscópicas nos demais órgãos analisados. Análises à procura de aflatoxinas, resíduos de pesticidas e isolamento bacteriano foram negativos. A análise da ração por cromatografia líquida revelou 37ppm de salinomicina na ração. A ração suspeita foi administrada a 12 chinchilas, três das quais (25% morreram apresentando lesões semelhantes às observadas nas chinchilas com a doença natural. O diagnóstico de intoxicação por salinomicina foi baseado na epidemiologia, lesões histológicas características e na presença de salinomicina na ração administrada nas quatro criações envolvidas.

  6. 青紫兰兔的生物净化技术探讨%Chinchilla Rabbit Biological Purification Technology

    Institute of Scientific and Technical Information of China (English)

    吴韬奋; 瞿伟; 黄国俊; 张瑞忠; 徐平

    2014-01-01

    Objective To establish the SPF Chinchil a rabbit populations, to meet the needs of various types of research. Methods Approach taken by Caesarean births method for biological purification Chinchil a rabbits, conducted on behalf of breast-fed rabbits with SPF level to achieve the SPF microbial level. Results Obtained Chinchil a rabbits 88, 74 survived, the survival rate was 84.1%. Conclusion Rabbits pre-production period to judge accurately, can improve the success rate of caesarean section.%目的:为建立SPF级青紫兰兔种群,满足各类研究的需要。方法用剖腹取胎的方法,对青紫兰种兔进行生物净化,用SPF级代乳兔进行喂养,使其微生物等级达到SPF级。结果共取得青紫兰仔兔88只,存活74只,存活率为84.1豫。结论种兔预产期判断准确,可提高剖腹产手术的成功率。

  7. Variation in response dynamics of regular and irregular vestibular-nerve afferents during sinusoidal head rotations and currents in the chinchilla.

    Science.gov (United States)

    Kim, Kyu-Sung; Minor, Lloyd B; Della Santina, Charles C; Lasker, David M

    2011-05-01

    In mammals, vestibular-nerve afferents that innervate only type I hair cells (calyx-only afferents) respond nearly in phase with head acceleration for high-frequency motion, whereas afferents that innervate both type I and type II (dimorphic) or only type II (bouton-only) hair cells respond more in phase with head velocity. Afferents that exhibit irregular background discharge rates have a larger phase lead re-head velocity than those that fire more regularly. The goal of this study was to investigate the cause of the variation in phase lead between regular and irregular afferents at high-frequency head rotations. Under the assumption that externally applied galvanic currents act directly on the nerve, we derived a transfer function describing the dynamics of a semicircular canal and its hair cells through comparison of responses to sinusoidally modulated head velocity and currents. Responses of all afferents were fit well with a transfer function with one zero (lead term). Best-fit lead terms describing responses to current for each group of afferents were similar to the lead term describing responses to head velocity for regular afferents (0.006 s + 1). This finding indicated that the pre-synaptic and synaptic inputs to regular afferents were likely to be pure velocity transducers. However, the variation in phase lead between regular and irregular afferents could not be explained solely by the ratio of type I to II hair cells (Baird et al 1988), suggesting that the variation was caused by a combination of pre- (type of hair cell) and post-synaptic properties.

  8. 灰兔眼巩膜厚度测量%Scleral thickness topography of the adult Chinchilla pigmented rabbit with implications for transscleral drug delivery research

    Institute of Scientific and Technical Information of China (English)

    李杰; 兰碧菲; 赵春晖; 程凌云

    2013-01-01

    Objective To measure the scleral thickness of the rabbit eye at different locations in the globe,providing a theoretical basis for advanced research in transscleral drug delivery.Methods In this experimental study,98 eyes of 49 adult pigmented rabbits were sacrificed after deep anesthesia and the eyeballs were enucleated and fixed in 1% buffered formaldehyde and 1.25% glutaraldehyde for a minimum of 36 hours.The eyes were processed for routine paraffin embedding and sectioning.The sagittal sections at the optic nerve level were collected and used for scleral thickness study.The images were acquired at serial locations between the limbus and optic nerve and the thickness was measured with SPOT image software.The data were analyzed with generalized estimating equations (GEE) and Tukey's HSD Post Hoc Test.Results In general,the mean scleral thickness of the inferior eye globe was significantly thinner than that of the superior globe (342.9±91.3 μm versus 400.4±67.6 μm,x2=43.57,P<0.01,GEE).There were no significant differences in the scleral thickness from the pre-equator vicinity to the posterior pole,with a mean thickness of 366.8±56.3 μm at the superior globe.For the inferior globe,the mean scleral thickness at the pre-equator vicinity and at the equator was similar,340.9±72.5 μm and 340.8±76.3 μm.However,scleral thickness decreased to 293.9±57.4 μm at the post-equator vicinity and to 209.0±51.8 μm at the posterior pole.The thinnest sclera was located immediately around the optic nerve,273.5±90.5 μm for the superior and 187.7±60.1 μm for the inferior,compared to the other locations (P<0.05,Tukey's HSD Post Hoc Test).Conclusion Rabbit sclera is thinner than human sclera.In the rabbit eye globe,the superior sclera is significantly thicker than the inferior sclera and superior sclera is shorter and more uniform in thickness between the equator and the posterior pole.Scleral thickness has larger variations between the limbus and equator than the variations between the equator and the posterior pole.%目的 测量灰兔不同部位巩膜厚度,了解巩膜部位与厚度变化关系,为经巩膜眼内给药实验研究提供诠释依据.方法 实验研究.49只(98眼)成年青紫蓝灰兔经麻醉后,安乐液处死,立即摘去眼球,随后放入1.25%戊二醛和1%多聚甲醛固定液固定,制成石蜡切片后行常规苏木精-伊红(HE)染色.经生物显微镜观察拍照后用图像分析软件测量从角巩膜缘部到视神经部的巩膜厚度.对测量结果采用广义估计方程(GEE)及Tukey's HSD Post Hoc Test分析.结果 下半部分兔眼巩膜比上半部分巩膜薄,分别是(342.9±91.3)μm和(400.4±-67.6)μm(x2--.43.57,P<0.01,GEE).上半部分巩膜厚度在赤道前后及后极部差异无统计学意义,平均为(366.8±56.3)μm.下半部分巩膜厚度在赤道前和赤道部为(340.9±72.5)μm和(340.8±76.3)μm,往后进一步变薄,赤道部后为(293.9±57.4)μm,后极部为(209.0±51.8)μm.上半部分和下半部分巩膜均在神经处最薄,分别为(273.5:±:90.5) μm和(187.7±60.1)μm,与其他部位相比,差异有统计学意义(P<0.05,Tukey's HSD Post Hoc Test).结论 兔眼巩膜上半部分比下半部分厚,从部位和厚度关系分析,厚度在角巩膜缘与赤道部之间变化较大,在赤道部和后极部之间变化较小.

  9. Threshold Shifts and Cochlear Injury in Chinchillas Exposed to Octave Bands of Noise Centered at 63 and 1000 HZ for 9 Days,

    Science.gov (United States)

    1982-10-01

    2.0 kHz. The 1000-Hz octave bands produced more permanent threshold shift at the lower 33 %.. . %. , Ic CV) 1 00 EuG LLS) 2C C LJ5- 0o x ezw CA OJ...Officer Commander Naval Medical R&D Command US Army Transportation School National Naval Medical Center ATTN: ATSPoTD-ST Bethesda, 1D 20014 (1) Fort

  10. Parvovirus-derived endogenous viral elements in two South American rodent genomes.

    Science.gov (United States)

    Arriagada, Gloria; Gifford, Robert J

    2014-10-01

    We describe endogenous viral elements (EVEs) derived from parvoviruses (family Parvoviridae) in the genomes of the long-tailed chinchilla (Chinchilla lanigera) and the degu (Octodon degus). The novel EVEs include dependovirus-related elements and representatives of a clearly distinct parvovirus lineage that also has endogenous representatives in marsupial genomes. In the degu, one dependovirus-derived EVE was found to carry an intact reading frame and was differentially expressed in vivo, with increased expression in the liver.

  11. [Use of mesenchymal stem cells for reparative processes activation in bone jaw tissue in experimental conditions].

    Science.gov (United States)

    Volozhin, A I; Vasil'ev, A Iu; Malyginov, N N; Bulanova, I M; Grigor''ian, A S; Kiseleva, E V; Cherniaev, S E; Tarasenko, I V

    2010-01-01

    In experiment on 12 Chinchilla rabbits dynamics of reparative regeneration was studied at the terms 2 and 4 months. Bone defect in mandible corner was closed by osteoplastic material Gapkol which was covered from inside by allogenic or autologic stem cells received from rabbit adipose tissue. The results of the ray tracing methods of study were verified by SEM and histological methods.

  12. Increased biofilm formation by nontypeable Haemophilus influenzae isolates from patients with invasive disease or otitis media versus strains recovered from cases of respiratory infections

    NARCIS (Netherlands)

    Puig, C.; Domenech, A.; Garmendia, J.; Langereis, J.D.; Mayer, P.; Calatayud, L.; Linares, J.; Ardanuy, C.; Marti, S.

    2014-01-01

    Biofilm formation by nontypeable (NT) Haemophilus influenzae remains a controversial topic. Nevertheless, biofilm-like structures have been observed in the middle-ear mucosa of experimental chinchilla models of otitis media (OM). To date, there have been no studies of biofilm formation in large coll

  13. Nontypeable Streptococcus pneumoniae as an Otopathogen

    Science.gov (United States)

    Xu, Qingfu; Kaur, Ravinder; Casey, Janet R.; Sabharwal, Vishakha; Pelton, Stephen; Pichichero, Michael E.

    2014-01-01

    Among 34 Spn sequential isolates from middle ear fluid we found a case of a nontypeable Streptococcus pneumoniae (NT-Spn) in a child with AOM. The strain was pneumolysin PCR positive and capsule gene PCR negative. Virulence of the NT-Spn was confirmed in a chinchilla model of AOM. PMID:21251566

  14. Zinc is sufficiently abundant within mammalian sperm nuclei to bind stoichiometrically with protamine 2.

    Science.gov (United States)

    Bench, G; Corzett, M H; Kramer, C E; Grant, P G; Balhorn, R

    2000-08-01

    Although studies have demonstrated that zinc can bind to sperm nuclear proteins, specifically protamine 2, it has not been shown that the metal is sufficiently abundant inside the sperm nucleus to interact stoichiometrically with these proteins. In this study proton-induced X-ray emission (PIXE) has been used to measure the amount of sulfur and zinc within the nuclei of individual sperm cells to infer the stoichiometry of zinc binding to protamine 2 in six species of mammal: bull, chinchilla, stallion, hamster, human, and mouse (protamine 2 comprises from 0% (bull) to 67% (mouse) of the protamine present in the sperm of these animals). Using the sulfur mass and electrophoretic data on the relative proportion of protamine 1 and protamine 2 in the sperm chromatin of these species, the protamine 1, protamine 2, and total protamine contents within each species sperm nuclei have been determined. The PIXE measurements reveal that the zinc content of the sperm nucleus varies proportionately with the protamine 2 content of sperm chromatin. PIXE analyses of hamster protamines extracted under conditions that appear to at least partially preserve zinc binding also confirm that the majority of the metal is bound to protamine. In five of the species examined, sufficient zinc is present for each protamine 2 molecule to bind one zinc. The results obtained for chinchilla sperm, conversely, indicate the chinchilla protamine 2 molecule may interact differently with zinc. Chinchilla sperm only contain enough zinc for one atom to be bound to two protamine 2 molecules.

  15. Rodent Oncology: Diseases, Diagnostics, and Therapeutics.

    Science.gov (United States)

    Hocker, Samuel E; Eshar, David; Wouda, Raelene M

    2017-01-01

    Cancer incidence in rodent species varies dramatically from a common occurrence in mice and rats to just a limited number of documented cases in chinchillas and degus. This article summarizes common tumors, both benign and malignant, that have been reported to occur in rodents. Outlined are clinical signs, diagnostics, and treatments that have been described for rodents presenting with specific neoplasms.

  16. Delays of stimulus-frequency otoacoustic emissions and cochlear vibrations contradict the theory of coherent reflection filtering

    NARCIS (Netherlands)

    Siegel, JH; Cerka, AJ; Recio-Spinoso, A; Temchin, AN; van Dijk, P; Ruggero, MA

    2005-01-01

    When stimulated by tones, the ear appears to emit tones of its own, stimulus-frequency otoacoustic emissions (SFOAEs). SFOAEs were measured in 17 chinchillas and their group delays were compared with a place map of basilar-membrane vibration group delays measured at the characteristic frequency. The

  17. 9 CFR 2.1 - Requirements and application.

    Science.gov (United States)

    2010-01-01

    ... animals, such as dogs, cats, birds, rabbits, hamsters, guinea pigs, gophers, domestic ferrets, chinchilla... animals for research or exhibition, or selling any wild, exotic, or nonpet animals retail, must have a license; (ii) Any person who sells or negotiates the sale or purchase of any animal except wild or...

  18. Elecciones de febrero de 2010: Los vaivenes de la bipolaridad electoral.

    OpenAIRE

    Paniagua, Isabel Brenes; Torres, Fernando Zeledón

    2011-01-01

    Contexto Histórico: Los vaivenes de la bipolaridadelectoral; Coyuntura Electoral 2010: Del Referénduma la caída de la Bolsa de NY; La Campaña;Resultados: El previsto inesperado triunfo de LauraChinchilla y Hallazgos: Transiciones, Desalineados y laRepatriación electoral

  19. Experimental investigation of the role of thyrocalcitonin in the prophylaxis of disturbances in the water-salt and mineral metabolism during a 30-day hypokinesia

    Science.gov (United States)

    Shashkov, V. S.; Yegorov, B. B.; Dmitriyev, B. S.; Volozhin, A. N.; Krotov, B. P.

    1979-01-01

    The effect of thyrocalcitonin (TCT) injections on the metabolism of water and electrolytes in free-moving and immobilized chinchilla hares is described. Calcium excretion from immobilized animals was elevated, but normalized in those also receiving TCT injections. TCT also normalized water content and excretion rates.

  20. The Effects of Blast Trauma (Impulse Noise) on Hearing: A Parametric Study Source II

    Science.gov (United States)

    1989-12-01

    rg/kg), Acepromazine (0.43 mg/kg) and Xylazine (2.57 mg/kg)) and made monaural by the surgical destruction of the left cochlea. A chronic electrode...and Jones, R.J. (1986). A chinchilla restraint system. USAARL Rpt. No. 86-1. Pfander, F., Bongartz, H. Brinkmann, H., and Kietz, H. (1980) " Danger of

  1. Adaptation of the vestibulo-ocular reflex for forward-eyed foveate vision.

    Science.gov (United States)

    Migliaccio, Americo A; Minor, Lloyd B; Della Santina, Charles C

    2010-10-15

    To maintain visual fixation on a distant target during head rotation, the angular vestibulo-ocular reflex (aVOR) should rotate the eyes at the same speed as the head and in exactly the opposite direction. However, in primates for which the 3-dimensional (3D) aVOR has been extensively characterised (humans and squirrel monkeys (Saimiri sciureus)), the aVOR response to roll head rotation about the naso-occipital axis is lower than that elicited by yaw and pitch, causing errors in aVOR magnitude and direction that vary with the axis of head rotation. In other words, primates keep the central part of the retinal image on the fovea (where photoreceptor density and visual acuity are greatest) but fail to keep that image from twisting about the eyes' resting optic axes. We tested the hypothesis that aVOR direction dependence is an adaptation related to primates' frontal-eyed, foveate status through comparison with the aVOR of a lateral-eyed, afoveate mammal (Chinchilla lanigera). As chinchillas' eyes are afoveate and never align with each other, we predicted that the chinchilla aVOR would be relatively low in gain and isotropic (equal in gain for every head rotation axis). In 11 normal chinchillas, we recorded binocular 3D eye movements in darkness during static tilts, 20-100 deg s(1) whole-body sinusoidal rotations (0.5-15 Hz), and 3000 deg s(2) acceleration steps. Although the chinchilla 3D aVOR gain changed with both frequency and peak velocity over the range we examined, we consistently found that it was more nearly isotropic than the primate aVOR. Our results suggest that primates' anisotropic aVOR represents an adaptation to their forward-eyed, foveate status. In primates, yaw and pitch aVOR must be compensatory to stabilise images on both foveae, whereas roll aVOR can be under-compensatory because the brain tolerates torsion of binocular images that remain on the foveae. In contrast, the lateral-eyed chinchilla faces different adaptive demands and thus enlists a

  2. Mineralización de uranio en la Sierra de Velasco, La Rioja

    Directory of Open Access Journals (Sweden)

    Orquídea Morello

    2013-09-01

    Full Text Available En esta contribución se describe una mineralización de uranio hallada en la sierra de Velasco, provincia de La Rioja, noroeste de Argentina. La geología de la región incluye granitos, pegmatitas y rocas metamórficas. Las rocas hospedantes de la mineralización son el granito La Chinchilla, de edad carbonífera y las metamorfitas del Complejo La Cébila, de edad precámbrica-ordovícica inferior. La mineralización es perigranítica; se encuentra diseminada, en fracturas y alojada en el contacto entre el granito y la metamorfita. En el granito La Chinchilla se identificó un óxido de U-Nb-Ta, y en las metamorfitas se reconocieron silicatos (uranofano, betauranofano, fosfatos (furcalita y meta-autunita y minerales negros de uranio (uraninita -variedad pechblenda- y coffinita.

  3. Development of a noise metric for assessment of exposure risk to complex noises.

    Science.gov (United States)

    Zhu, Xiangdong; Kim, Jay H; Song, Won Joon; Murphy, William J; Song, Seongho

    2009-08-01

    Many noise guidelines currently use A-weighted equivalent sound pressure level L(Aeq) as the noise metric and the equal energy hypothesis to assess the risk of occupational noises. Because of the time-averaging effect involved with the procedure, the current guidelines may significantly underestimate the risk associated with complex noises. This study develops and evaluates several new noise metrics for more accurate assessment of exposure risks to complex and impulsive noises. The analytic wavelet transform was used to obtain time-frequency characteristics of the noise. 6 basic, unique metric forms that reflect the time-frequency characteristics were developed, from which 14 noise metrics were derived. The noise metrics were evaluated utilizing existing animal test data that were obtained by exposing 23 groups of chinchillas to, respectively, different types of noise. Correlations of the metrics with the hearing losses observed in chinchillas were compared and the most promising noise metric was identified.

  4. ModA2 Phasevarion Switching in Nontypeable Haemophilus influenzae Increases the Severity of Experimental Otitis Media.

    Science.gov (United States)

    Brockman, Kenneth L; Jurcisek, Joseph A; Atack, John M; Srikhanta, Yogitha N; Jennings, Michael P; Bakaletz, Lauren O

    2016-09-01

    Several human-adapted bacterial pathogens use a phasevarion (ie, a phase-variable regulon) to rapidly and reversibly regulate the expression of many genes, which include known virulence factors, yet the influence of phasevarion-mediated regulation in pathogenesis remains poorly understood. Here we examine the impact of the nontypeable Haemophilus influenzae (NTHI) ModA2 phasevarion on pathogenesis and disease severity in a chinchilla model of experimental otitis media. Chinchillas were challenged with NTHI variant populations that were either inoculated ON and remained ON, inoculated OFF and shifted ON, or inoculated OFF and remained OFF, within the middle ear. We show that populations that shift from OFF to ON within the middle ear induce significantly greater disease severity than populations that are unable to shift. These observations support the importance of phasevarion switching in NTHI pathogenesis and the necessity to considered phasevarion regulation when developing methods to treat and prevent infection.

  5. Guatemalan Immigration to San Francisco Bay Area

    OpenAIRE

    Manz, Beatriz; Perry-Houts, Ingrid; Castaneda, Xochitl

    2000-01-01

    Increasing numbers of Central Americans, primarily from El Salvador and Guatemala, began arriving in the United States in the early 1980s, fleeing brutal military repression and counterinsurgency efforts in their home countries (Hamilton and Chinchilla-Stoltz 1991, 1998; Julian 1994; Bens 1996; Burns 1988). The Commission for Historical Clarification (CEH) concludes that 200,000 people were killed or disappeared, and that state forces and related paramilitary groups onslaught, from 1981 to 1...

  6. Coagulating activity of the blood, vascular wall, and myocardium under hypodynamia conditions

    Science.gov (United States)

    Petrovskiy, B. V. (Editor); Chazov, E. I. (Editor); Andreyev, S. V. (Editor)

    1980-01-01

    In order to study the effects of hypodynamia on the coagulating properties of the blood, vascular wall, and myocardium, chinchilla rabbits were kept for varying periods in special cages which restricted their movements. At the end of the experiment, blood samples were taken and the animals were sacrificed. Preparations were made from the myocardium venae cavae, and layers of the aorta. Two resultant interrelated and mutually conditioned syndromes were discovered: thrombohemorrhagic in the blood and hemorrago-thrombotic in the tissues.

  7. Survey of Hymenolepis spp. in pet rodents in Italy.

    Science.gov (United States)

    d'Ovidio, D; Noviello, Emilio; Pepe, P; Del Prete, L; Cringoli, G; Rinaldi, L

    2015-12-01

    We carried out the first survey of Hymenolepis spp. infection in pet rodents in Italy. Fresh fecal samples were collected from 172 pet rodents as follows: guinea pigs (Cavia porcellus; n = 60), squirrels (Callosciurus finlaysonii, Callosciurus prevosti, Tamias striatus, Tamias sibiricus, Sciurus calorinensis; n = 52), hamsters (Phodopus campbelli, Mesocricetus auratus; n = 30), chinchillas (Chinchilla lanigera; n = 13), rats (Rattus norvegicus; n = 10), and mice (Mus minutoides; n = 7). These animals were housed either in pet shops or in private houses. All fecal samples were processed using the FLOTAC pellet technique to assess the number of eggs per gram (EPG) of feces. Eggs of Hymenolepis nana were found in 24 out of 172 (13.9 %; 95 % confidence interval = 9.3-20.2 %) pet rodents. Of those rodents, 41.6 % (10/24) were rats (mean EPG = 55.7; range = 2-200), 29.2 % (7/24) mice (mean EPG = 64.5; range = 32-120), 25.0 % (6/24) were chinchillas (mean EPG = 25.5; range = 10-50), and 4.2 % (1/24) hamsters (P. campbelli) (EPG = 86.0). In addition, Hymenolepis diminuta eggs were found in 2 out of 172 (1.2 %; 95 % confidence interval = 0.2-4.6 %) rodents examined, both of which (100 %; 2/2) were pet squirrels (C. prevosti) (mean EPG = 10; range = 4-16). To the authors' knowledge, this is the first report of a natural infection of H. diminuta in pet squirrels.

  8. INTERFERENCIA ENTRE BACTERIAS COMENSALES DE FARINGE Y PATÓGENAS DE OÍDO MEDIO EN UN MODELO ANIMAL DE OTITIS MEDIA

    Directory of Open Access Journals (Sweden)

    LM Villafañe

    2012-01-01

    Full Text Available Objetivo: determinar in vivo la interacción entre bacterias comensales aisladas de faringe de niños sanos y S. pneumoniae, en un modelo animal (Chinchilla laniger de otitis media. Metodos: estudio experimental Intervenciones: Suspensiones de los serotipos 18A y 9V de Spn fueron inyectados intra-peritonealmente en dos chinchillas y luego recuperados mediante cultivo de órganos y sangre de las mismas. Empleando suspensiones de las cepas animalizadas se inocularon intranasalmente cuatro chinchillas, y solo a dos de ellas se le inoculo una mezcla de las bacterias comensales (Streptococcus mitis, Streptococcus parasanguinis. Con un otoscopio se examinó la evolución de la infección a los 7 y 14 días. Se sacrificaron los animales y se tomaron muestras de los oídos para un examen histológico. Resultados: Mediante otoscopia, se observó al día 14 que todos presentaron una membrana timpánica hiperémica sin efusión, presentándose con mayor intensidad en aquellos que recibieron el tratamiento. La histología confirmó que la administración del tratamiento no evitó que la infección evolucionara, advirtiéndose que las infectadas con el serotipo 8A y tratadas fueron las que presentaron el tejido epitelial menos comprometido respecto al resto. Conclusiones: Spn y las bacterias comensales podrían establecer una relación competitiva, y el efecto moderador en la progresión de la infección de otitis media dependería del serotipo involucrado.

  9. Interferencia entre bacterias comensales de faringe y patogénesis de oído medio en un modelo animas de otitis media

    Directory of Open Access Journals (Sweden)

    LM Villafane

    2013-01-01

    Full Text Available Objetivo: determinar in vivo la interacción entre bacterias comensales aisladas  de faringe de niños sanos y S. pneumoniae, en un modelo animal (Chinchilla laniger de otitis media. Metodos: estudio experimental Intervenciones: Suspensiones de los serotipos 18A y 9V de Spn fueron inyectados intra-peritonealmente en dos chinchillas y luego recuperados mediante cultivo de órganos y sangre de las mismas. Empleando suspensiones de las cepas animalizadas se inocularon intranasalmente cuatro chinchillas, y solo a dos de ellas se le inoculo una mezcla de las bacterias comensales (Streptococcus mitis, Streptococcus parasanguinis. Con un otoscopio se examinó la evolución de la infección a los 7 y 14 días. Se sacrificaron los animales y se tomaron muestras de los oídos para un examen histológico. Resultados: Mediante otoscopia, se observó al día 14 que todos presentaron una membrana timpánica hiperémica sin efusión, presentándose con mayor intensidad en aquellos que recibieron el tratamiento. La histología confirmó que la administración del tratamiento no evitó que la infección evolucionara, advirtiéndose que las infectadas con el serotipo 8A y tratadas fueron las que presentaron el tejido epitelial menos comprometido respecto al resto. Conclusiones: Spn y las bacterias comensales podrían establecer una relación competitiva, y el efecto moderador en la progresión de la infección de otitis media dependería del serotipo involucrado.

  10. Reproductive performance of different breeds of broiler rabbits under sub-temperate climatic conditions

    Directory of Open Access Journals (Sweden)

    D. Kumar

    2013-09-01

    Full Text Available This study was conducted to assess the effect of breed, season, age and weight of doe at mating on reproductive performance of 4 broiler rabbit breeds, Grey Giant, White Giant, Soviet Chinchilla, and New Zealand White, reared under standard management practices in sub-temperate climatic conditions of India. They were first mated at 6 to 7 mo of age, whereupon an extensive breeding system (re-mating after weaning was followed. Weaning was done 42 d after kindling. The data from the records on reproduction consisting of 503 matings and 377 kindlings were analysed. The parameters considered were fertility rate, litter size at birth (LSB, litter weight at birth (LWB, litter size at weaning (LSW, litter weight at weaning (LWW, doe weight at mating (DWM, gestation length and sex ratio. Among 4 breeds, the LSB, LWB and LSW were higher in Grey Giant followed by White Giant, Soviet Chinchilla and New Zealand White. The LSB and LSW in Grey Giant breed differed significantly (P<0.05 from Soviet Chinchilla and New Zealand White. Season had significant (P<0.05 effect on LSW with higher values during spring (5.68±0.24, followed by summer (5.29±0.30, winter (5.13±0.25 and autumn (4.17±0.49. The body weight of doe at service significantly influenced fertility. The fertility increased as body weight increased. The age of the doe at mating had a significant effect on LSW, with higher values for does more than 2 yr and less than 1 yr old compared to 1- to 2-yr old does. The parity did not affect any of the parameters studied. It is concluded that the factors studied affect the reproductive performance of rabbit does. Grey Giant breed showed the highest litter size at birth and weaning, and the highest litter size and weight at weaning was in spring.

  11. Chemical Separation of Fixed Tissue Using Thermolysin

    Directory of Open Access Journals (Sweden)

    Anahita Dua

    2013-01-01

    Full Text Available Thermolysin is a metallopeptidase used to cleave peptide bonds at specific junctions. It has previously been used to cleave specific amino acid sequences found at the junction of the sensory epithelium and underlying stroma of unfixed otolithic organs of the vestibular system. We have used thermolysin to separate sensory epithelium from the underlying stroma in fixed cristae ampullares of mouse, rat, gerbil, guinea pig, chinchilla, and tree squirrel, thus removing the saddle-shaped curvature of the sensory organ and creating a flattened sensory epithelium preparation. This permits visualization of the entire sensory organ in a single mount and facilitates proper morphometric analysis.

  12. Surgical sterilization in small mammals. Spay and castration.

    Science.gov (United States)

    Jenkins, J R

    2000-09-01

    The intrinsic physiologic and anatomic differences between small exotic mammals and the species that are more familiar to veterinary practitioners (i.e., dogs and cats) are substantial. This discussion is limited to rabbits, mice and rats (murid rodents), hamsters and gerbils (cricetid rodents), and guinea pigs and chinchillas (hystricomorph rodents). In addition to their anatomic and physiologic differences, differences in behaviors, such as their reaction to stress and pain, exist. Preoperative and postoperative care, basic surgical techniques unique to these species, and useful materials are discussed.

  13. [Evaluation of reparative regeneration of the jaw bone by microfocus roentgenography in an experiment].

    Science.gov (United States)

    Vasil'ev, A Iu; Bulanova, I M; Mal'ginov, N N; Tarasenko, I V; Tarasenko, S V; Kiseleva, E V; Drobyshev, A Iu; Volozhin, A I

    2009-01-01

    In experiment on 16 grown-up chinchilla rabbits the dynamic of reparative regeneration was evaluated by digital microfocal rontgenography in the terms of 1, 2 and 4 months. Bone defect of the 8capital CHE, Cyrillic8 mm size in the region of mandible angle was caused by surgical laser Smart 2940 D+ on the right side and by physiodespenser Surgec XT on the left side. Surgical laser use let to reduce intact mother bone traumatisation and to improve remote results of bone tissue regeneration. After bone defect creation bone tissue regeneration was put into effect by all 3 callus types - endosteal, periosteal and intermediary.

  14. Subiendo las gradas: Características del desarrollo evolutivo de un grupo de estudiantes que ingresa a sétimo año y su influencia en la transición de primaria a secundaria

    OpenAIRE

    Chinchilla Cervantes, Ana Cecilia

    2014-01-01

    Chinchilla, A. SUBIENDO LAS GRADAS: CARACTERÍSTICAS DEL DESARROLLO EVOLUTIVO DE UN GRUPO DE ESTUDIANTES QUE INGRESA A SÉTIMO AÑO Y SU INFLUENCIA EN LA TRANSICIÓN DE PRIMARIA A SECUNDARIA. (Bajo la dirección de Dr. Rafael Ángel Espinoza Pizarro, Universidad Estatal a Distancia, Sistema de Estudios de Posgrado, Febrero, 2011). El presente estudio investigativo tuvo como propósito conocer las características del desarrollo evolutivo de un grupo de estudiantes que ingresa a sétimo año con m...

  15. THE EFFECT OF BREED ON REPRODUCTIVE PERFORMANCE IN COMMODITY RABBIT PRODUCTION

    Directory of Open Access Journals (Sweden)

    Jadwiga TOPCZEWSKA

    2013-06-01

    Full Text Available The aim of this study was to assess the reproductive rates among different breeds, mostly used in commodity farm conditions. The studies were obtained at fertility level from 6.27 animals in the Californian breed to 8.49 animals in Popielno White. High rate of failures during rearing was observed in the Californian breed. Litter weight was dependent on the number of births and young rearing, lactation and care of female. Kitten weight at 35 day of age ranged from 603.21g (Alaskan to 736.10g (Giant Chinchilla. The results indicate the usefulness of a Popielno White breed for the livestock production.

  16. Nonlinear dynamics of the mammalian inner ear

    CERN Document Server

    Szalai, Robert; Homer, Martin

    2015-01-01

    A simple nonlinear transmission-line model of the cochlea with longitudinal coupling is introduced that can reproduce Basilar membrane response and neural tuning in the chinchilla. It is found that the middle ear has little effect on cochlear resonances, and hence conclude that the theory of coherent reflections is not applicable to the model. The model also provides an explanation of the emergence of spontaneous otoacoustic emissions (SOAEs). It is argued that SOAEs arise from Hopf bifurcations of the transmission-line model and not from localized instabilities. The paper shows that emissions can become chaotic, intermittent and fragile to perturbations.

  17. Structural and Functional Studies of the Protamine 2-Zinc Complex from Syrian Gold Hamster (Mesocricetus Auratus) Spermatids and Sperm

    Energy Technology Data Exchange (ETDEWEB)

    Dolan, Cheryl E. [Univ. of California, Davis, CA (United States)

    2004-08-30

    The research described in this dissertation consists of four major areas: (1) sequence analysis of protamine 2 from Muroid rodents to identify potential zinc-binding domain(s) of protamine 2; (2) structural studies of the protamine 2-zinc complex from Syrian Gold hamster sperm and spermatids to elucidate the role of zinc during spermiogenesis; (3) structural studies of an unique protamine 2-zinc complex from chinchilla sperm; and (4) Nuclear Magnetic Resonance (NMR) studies of soluble complexes of hairpin oligonucleotides with synthetic arginine-rich peptides or protamine 1 isolated from bull sperm. First, zinc was quantitated in spermatids and sperm by Proton-Induced X-ray Emission (PIXE) to determine whether zinc is present in the early stages of spermiogenesis. The PIXE results revealed the zinc content varies proportionately with the amount of protamine 2 in both spermatid and sperm nuclei. An exception was chinchilla sperm containing twice the amount of protamine 2 than zinc. Further analyses by PIXE and X-ray Absorption Spectroscopy (XAS) of zinc bound to protamines isolated from hamster sperm confirmed the majority of the zinc is bound to protamine and identified the zinc ligands of protamine 2 in hamster spermatids and sperm in vivo. These studies established that zinc is bound to the protamine 2 precursor in hamster spermatids and the coordination of zinc by protamine 2 changes during spermiogenesis. Finally, the sequence analysis combined with the XAS results suggest that the zinc-binding domain in protamine 2 resides in the amino-terminus. Similar analyses of chinchilla sperm by XAS were performed to clarify the unusual PIXE results and revealed that chinchilla has an atypical protamine 2-zinc structure. Two protamine 2 molecules coordinate one zinc atom, forming homodimers that facilitate the binding of protamine 2 to DNA and provide an organizational scheme that would accommodate the observed species-specific protamine stoichiometry in mammalian sperm

  18. The multifunctional host defense peptide SPLUNC1 is critical for homeostasis of the mammalian upper airway.

    Directory of Open Access Journals (Sweden)

    Glen McGillivary

    Full Text Available Otitis media (OM is a highly prevalent pediatric disease caused by normal flora of the nasopharynx that ascend the Eustachian tube and enter the middle ear. As OM is a disease of opportunity, it is critical to gain an increased understanding of immune system components that are operational in the upper airway and aid in prevention of this disease. SPLUNC1 is an antimicrobial host defense peptide that is hypothesized to contribute to the health of the airway both through bactericidal and non-bactericidal mechanisms. We used small interfering RNA (siRNA technology to knock down expression of the chinchilla ortholog of human SPLUNC1 (cSPLUNC1 to begin to determine the role that this protein played in prevention of OM. We showed that knock down of cSPLUNC1 expression did not impact survival of nontypeable Haemophilus influenzae, a predominant causative agent of OM, in the chinchilla middle ear under the conditions tested. In contrast, expression of cSPLUNC1 was essential for maintenance of middle ear pressure and efficient mucociliary clearance, key defense mechanisms of the tubotympanum. Collectively, our data have provided the first in vivo evidence that cSPLUNC1 functions to maintain homeostasis of the upper airway and, thereby, is critical for protection of the middle ear.

  19. Taxonomic Characterization and Secondary Metabolite Profiling of Aspergillus Section Aspergillus Contaminating Feeds and Feedstuffs

    Science.gov (United States)

    Greco, Mariana; Kemppainen, Minna; Pose, Graciela; Pardo, Alejandro

    2015-01-01

    Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60%) were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%). These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds. PMID:26364643

  20. Damage of the auditory system associated with acute blast trauma.

    Science.gov (United States)

    Roberto, M; Hamernik, R P; Turrentine, G A

    1989-05-01

    This paper reviews the results of several studies on the effects of blast wave exposure on the auditory system of the chinchilla, the pig, and the sheep. The chinchillas were exposed at peak sound pressure levels of approximately 160 dB under well-controlled laboratory conditions. A modified shock tube was used to generate the blast waves. The pigs and sheep were exposed under field conditions in an instrumented hard-walled enclosure. Blast trauma was induced by the impact of a single explosive projectile. The peak sound pressure levels varied between 178 and 209 dB. All animals were killed immediately following exposure, and their temporal bones were removed for fixation and histologic analysis using light microscopy and scanning electron microscopy. Middle ears were examined visually for damage to the conductive system. There were well-defined differences in susceptibility to acoustic trauma among species. However, common findings in each species were the acute mechanical fracture and separation of the organ of Corti from the basilar membrane, and tympanic membrane and ossicular failure.

  1. Fatigue Modeling via Mammalian Auditory System for Prediction of Noise Induced Hearing Loss

    Directory of Open Access Journals (Sweden)

    Pengfei Sun

    2015-01-01

    Full Text Available Noise induced hearing loss (NIHL remains as a severe health problem worldwide. Existing noise metrics and modeling for evaluation of NIHL are limited on prediction of gradually developing NIHL (GDHL caused by high-level occupational noise. In this study, we proposed two auditory fatigue based models, including equal velocity level (EVL and complex velocity level (CVL, which combine the high-cycle fatigue theory with the mammalian auditory model, to predict GDHL. The mammalian auditory model is introduced by combining the transfer function of the external-middle ear and the triple-path nonlinear (TRNL filter to obtain velocities of basilar membrane (BM in cochlea. The high-cycle fatigue theory is based on the assumption that GDHL can be considered as a process of long-cycle mechanical fatigue failure of organ of Corti. Furthermore, a series of chinchilla experimental data are used to validate the effectiveness of the proposed fatigue models. The regression analysis results show that both proposed fatigue models have high corrections with four hearing loss indices. It indicates that the proposed models can accurately predict hearing loss in chinchilla. Results suggest that the CVL model is more accurate compared to the EVL model on prediction of the auditory risk of exposure to hazardous occupational noise.

  2. Taxonomic Characterization and Secondary Metabolite Profiling of Aspergillus Section Aspergillus Contaminating Feeds and Feedstuffs.

    Science.gov (United States)

    Greco, Mariana; Kemppainen, Minna; Pose, Graciela; Pardo, Alejandro

    2015-09-02

    Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60%) were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%). These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds.

  3. Taxonomic Characterization and Secondary Metabolite Profiling of Aspergillus Section Aspergillus Contaminating Feeds and Feedstuffs

    Directory of Open Access Journals (Sweden)

    Mariana Greco

    2015-09-01

    Full Text Available Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60% were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%. These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds.

  4. Capsular switching as a strategy to increase pneumococcal virulence in experimental otitis media model.

    Science.gov (United States)

    Sabharwal, Vishakha; Stevenson, Abbie; Figueira, Marisol; Orthopoulos, George; Trzciński, Krzysztof; Pelton, Stephen I

    2014-04-01

    We hypothesized that capsular switch event, in which pneumococcus acquires a new capsule operon by horizontal gene transfer, may result in emergence of strains with increased virulence in acute otitis media. Using serotype 6A strain from a patient with invasive pneumococcal disease and clonally distant serotype 6C strain isolated from asymptomatic carrier we created 6A:6C (6A background with 6C capsule) capsular transformants and applied whole genome macro-restriction analysis to assess conservation of the 6A chassis. Next, we assessed complement (C3) and antibodies deposition on surface of pneumococcal cells and tested capsule recipient, capsule donor and two 6A:6C transformants for virulence in chinchilla experimental otitis media model. Both 6A:6C(1 or 2) transformants bound less C3 compared to 6C capsule-donor strain but more compared to serotype 6A capsule-recipient strain. Pneumococci were present in significantly higher proportion of ears among animals challenged with either of two 6A:6C(1 or 2) transformants compared to chinchillas infected with 6C capsule-donor strain [p < 0.001] whereas a significantly decreased proportion of ears were infected with 6A:6C(1 or 2) transformants as compared to 6A capsule-recipient strain. Our observations though limited to two serotypes demonstrate that capsular switch events can result in Streptococcus pneumoniae strains of enhanced virulence for respiratory tract infection.

  5. Fatigue Modeling via Mammalian Auditory System for Prediction of Noise Induced Hearing Loss.

    Science.gov (United States)

    Sun, Pengfei; Qin, Jun; Campbell, Kathleen

    2015-01-01

    Noise induced hearing loss (NIHL) remains as a severe health problem worldwide. Existing noise metrics and modeling for evaluation of NIHL are limited on prediction of gradually developing NIHL (GDHL) caused by high-level occupational noise. In this study, we proposed two auditory fatigue based models, including equal velocity level (EVL) and complex velocity level (CVL), which combine the high-cycle fatigue theory with the mammalian auditory model, to predict GDHL. The mammalian auditory model is introduced by combining the transfer function of the external-middle ear and the triple-path nonlinear (TRNL) filter to obtain velocities of basilar membrane (BM) in cochlea. The high-cycle fatigue theory is based on the assumption that GDHL can be considered as a process of long-cycle mechanical fatigue failure of organ of Corti. Furthermore, a series of chinchilla experimental data are used to validate the effectiveness of the proposed fatigue models. The regression analysis results show that both proposed fatigue models have high corrections with four hearing loss indices. It indicates that the proposed models can accurately predict hearing loss in chinchilla. Results suggest that the CVL model is more accurate compared to the EVL model on prediction of the auditory risk of exposure to hazardous occupational noise.

  6. On the self-organization of magnetic field and highly diluted matter in astrophysics

    Science.gov (United States)

    Berdichevsky, D. B.

    2015-12-01

    It is explored the self organization of matter and field in regions beyond our common reach on the surface of our planet and its atmospheric surroundings. This state of matter, which most basic property, the freezing in the magnetic field, see e.g., Chew et al, 1956, has proved to exist in the regions where robotic observations in the near and far space perform detailed observations of magnetic fields, and extreme dilute plasma (commonly about 1000 to 0.1 or less ionized particles per cubic cm). We present and discuss here simple hypotheses on the nature of what could be this state of magnetized matter which in the electron distribution shows a shape which often can successfully be described with a kappa distribution when inside a strongly magnetized transient, of the magnetic cloud kind, see e.g., Nieves Chinchilla and Figueroa-Viñas, 2008. This work is in many ways an extension of Alfven work on magnetized space plasmas, Alven, 1942. Chew, G.F., M.L., Goldberger, and F.E. Low, 1956, the Royal Soc. London, section Math & Phys Sc., 236, pp. 112. Nieves-Chinchilla, T., and A., Figueroa-Viñas, 2008, J. Geophys. Res., 113, A02105. Alfvén, H (1942). "Existence of electromagnetic-hydrodynamic waves". Nature 150: 405.. doi:10.1038/150405d0

  7. Kurtosis corrected sound pressure level as a noise metric for risk assessment of occupational noises.

    Science.gov (United States)

    Goley, G Steven; Song, Won Joon; Kim, Jay H

    2011-03-01

    Current noise guidelines use an energy-based noise metric to predict the risk of hearing loss, and thus ignore the effect of temporal characteristics of the noise. The practice is widely considered to underestimate the risk of a complex noise environment, where impulsive noises are embedded in a steady-state noise. A basic form for noise metrics is designed by combining the equivalent sound pressure level (SPL) and a temporal correction term defined as a function of kurtosis of the noise. Several noise metrics are developed by varying this basic form and evaluated utilizing existing chinchilla noise exposure data. It is shown that the kurtosis correction term significantly improves the correlation of the noise metric with the measured hearing losses in chinchillas. The average SPL of the frequency components of the noise that define the hearing loss with a kurtosis correction term is identified as the best noise metric among tested. One of the investigated metrics, the kurtosis-corrected A-weighted SPL, is applied to a human exposure study data as a preview of applying the metrics to human guidelines. The possibility of applying the noise metrics to human guidelines is discussed.

  8. Abrocomaphthirus hoplai, a new genus and species of sucking louse from Chile and its relevance to zoogeography.

    Science.gov (United States)

    Durden, L A; Webb, J P

    1999-10-01

    Both sexes of Abrocomaphthirus hoplai, new genus and new species (Anoplura: Polyplacidae), are described and illustrated. The endemic Chilean chinchilla rat Abrocoma bennetti Waterhouse (Rodentia: Abrocomidae) is the type host. The definition of the family Polyplacidae is amended to accommodate the new genus. Polyplax longa (Werneck), also referred to in the literature as Neohaematopinus longus Werneck, is reassigned to Abrocomaphthirus. The host of A. longus comb.n., is Abrocoma cinerea Thomas, another chinchilla rat, which inhabits parts of Argentina, Bolivia, Chile and Peru. The erection of Abrocomaphthirus as a distinct genus has important zoogeographical and evolutionary implications. The tenuous anomaly of P. longa being the sole native representative of the genus Polyplax in South America, possibly with African affinities, is now refuted. Instead, partial colonization of the neotropics by native species of both Polyplax and Neohaematopinus appears to have been relatively recent and from North America. The phylogenetic affinities of Abrocomaphthirus are unknown, but it appears to be closely related to other, more ancient, native South American polyplacid louse genera, such as Cuyana, Eulinognathus, Galeophthirus, and Lagidiophthirus. Arguments are presented in support of an ancestral zoogeographical link to Africa for these louse genera.

  9. Increased resistance to free radical damage induced by low-level sound conditioning.

    Science.gov (United States)

    Harris, Kelly Carney; Bielefeld, Eric; Hu, Bo Hua; Henderson, Donald

    2006-03-01

    Conditioning is the phenomenon where exposure to moderate-level acoustic stimuli can increase the ear's resistance to subsequent more intense sound exposures. In recent years, research has shown that conditioning increases the availability of antioxidant enzymes which presumably protects the ear from oxidative stress induced by a traumatic noise exposure [Jacono, A.A., Hu, B., Kopke, R.D., Henderson, D., Van De Water, T.R., Steinman, H.M., 1998. Changes in cochlear antioxidant enzyme activity after sound conditioning and noise exposure in the chinchilla. Hear Res 117, 31-8]. The current study was designed to assess whether the increase in endogenous antioxidants seen following conditioning could provide protection from oxidative stress induced by Paraquat, a potent generator of superoxide. Chinchillas were exposed to a conditioning noise, 500 Hz OBN at 95 dB for 6 h/day for 10 days, followed 5 days later with Paraquat application to the round window. Controls underwent the Paraquat application surgery, without prior conditioning. Evoked potential thresholds were determined prior to conditioning, at day 1, 5 and 10 during conditioning, at day 15 (5 days after conditioning), and at day 17, 19, 23, and 35 (1, 3, 7, and 20 days post-Paraquat). The conditioned animals showed reductions in permanent threshold shift and reduced inner hair cell loss relative to controls. These results reinforce the hypothesis that antioxidants are primary mediators of the conditioning effect.

  10. Characterization of the 3D angular vestibulo-ocular reflex in C57BL6 mice.

    Science.gov (United States)

    Migliaccio, Americo A; Meierhofer, Robert; Della Santina, Charles C

    2011-05-01

    We characterized the three-dimensional angular vestibulo-ocular reflex (3D aVOR) of adult C57BL6 mice during static tilt testing, sinusoidal, and high-acceleration rotations and compared it with that of another lateral-eyed mammal with afoveate retinae (chinchilla) and two primate species with forward eye orientation and retinal foveae (human and squirrel monkey). Noting that visual acuity in mice is poor compared to chinchillas and even worse compared to primates, we hypothesized that the mouse 3D aVOR would be relatively low in gain (eye-velocity/head-velocity) compared to other species and would fall off for combinations of head rotation velocity and frequency for which peak-to-peak position changes fall below the minimum visual angle resolvable by mice. We also predicted that as in chinchilla, the mouse 3D aVOR would be more isotropic (eye/head velocity gain independent of head rotation axis) and better aligned with the axis of head rotation than the 3D aVOR of primates. In 12 adult C57BL6 mice, binocular 3D eye movements were measured in darkness during whole-body static tilts, 20-100°/s whole-body sinusoidal rotations (0.02-10 Hz) and acceleration steps of 3,000°/s² to a 150°/s plateau (dominant spectral content 8-12 Hz). Our results show that the mouse has a robust static tilt counter-roll response gain of ~0.35 (eye-position Δ/head-position Δ) and mid-frequency aVOR gain (~0.6-0.8), but relatively low aVOR gain for high-frequency sinusoidal head rotations and for steps of head rotation acceleration (~0.5). Due to comparatively poor static visual acuity in the mouse, a perfectly compensatory 3D aVOR would confer relatively little benefit during high-frequency, low-amplitude movements. Therefore, our data suggest that the adaptive drive for maintaining a compensatory 3D aVOR depends on the static visual acuity in different species. Like chinchillas, mice have a much more nearly isotropic 3D aVOR than do the primates for which comparable data are

  11. Reseñas bibliográficas

    OpenAIRE

    Romero-Pérez, Jorge Enrique

    2014-01-01

    Se presentan las siguientes reseñas bibliográficas:       Hines Céspedes, César: La discrecionalidad administrativa y su control en Costa Rica (2006)/Reseñado por J. Enrique Romero P.      Rojas Franco, Enrique: Derecho administrativo de Costa Rica (2006)/Reseñado por J. Enrique Romero P.     Chinchilla Calderón, Rosaura: Jurisdicción penal de hacienda y de la función pública. Compendio normativo y jurisprudencial (2006)/Reseñado por J. Enrique Romero P.      Peña Chacón, Mario: Daño, respons...

  12. Experimental chemotherapy of mammalian coccidiosis with Bay g 7183.

    Science.gov (United States)

    Haberkorn, A; Schulz, H P

    1981-01-01

    Bay g 7183, a substituted sym. triazintrione derivative has a known high efficacy against poultry coccidia. Experimental investigations using the mouse coccidia E. falciformis indicated an activity also against mammalian coccidia. Minimum effective daily doses range between 0.25 to 10 mg/kg. Eimeria species used: E. falciformis (mouse(, E. contorta (rat), E. chinchillae (Mastomys), E. irresidua, E. magna, E. media, E. perforans, E. stiedae (rabbit), E. ashata, E. arloingi, E. faurei, E. ninakohlyakimovi, E. parva (sheep). A very appropriate mode of treatment, e.g. for rabbits is the dermal one (pour on) beside the oral route by using a stomach tube or with medicated food. Bay g 7183 is active both on schizogonic stages and gamonts. This explains the high efficacy even of single doses. If given e.g. once weekly it prevents or stops development of even massive experimental infections and their clinical symptoms. The value of E. falciformis as a test model is discussed.

  13. Monoclonal antibodies against DNA-binding tips of DNABII proteins disrupt biofilms in vitro and induce bacterial clearance in vivo

    Directory of Open Access Journals (Sweden)

    Laura A. Novotny

    2016-08-01

    Full Text Available The vast majority of chronic and recurrent bacterial diseases are attributed to the presence of a recalcitrant biofilm that contributes significantly to pathogenesis. As such, these diseases will require an innovative therapeutic approach. We targeted DNABII proteins, an integral component of extracellular DNA (eDNA which is universally found as part of the pathogenic biofilm matrix to develop a biofilm disrupting therapeutic. We show that a cocktail of monoclonal antibodies directed against specific epitopes of a DNABII protein is highly effective to disrupt diverse biofilms in vitro as well as resolve experimental infection in vivo, in both a chinchilla and murine model. Combining this monoclonal antibody cocktail with a traditional antibiotic to kill bacteria newly released from the biofilm due to the action of the antibody cocktail was highly effective. Our results strongly support these monoclonal antibodies as attractive candidates for lead optimization as a therapeutic for resolution of bacterial biofilm diseases.

  14. [Morphological manifestations of systemic atherosclerosis found in fundus (experimental study)].

    Science.gov (United States)

    Budzinskaia, M V; Fedorov, A A; Pliukhova, A A; Voevodina, T M; Balatskaia, N V

    2013-01-01

    Results of angiography and morphology of 32 eyes (16 chinchilla rabbits) with experimental atherosclerosis are presented. N.N. Anichkov and S.S. Khalatova experimental hypercholesterolemia model (1912) was used. The animals were divided into the following groups: initial and advanced atherosclerosis, control group, follow-up 3 and 6 months. After 3 months progressive reduction of perfused retinal vessels and early degenerative changes of neurons and photoreceptors were found. In 6 months these changes became more significant and generalized. Due to ongoing small vessel reduction blood flow went to the major vessels and changed its distribution followed by ischemia of adjacent retina. No changes in choriocapillary layer and retinal pigment epithelium were found in any of groups studied.

  15. Otoacoustic Estimates of Cochlear Tuning: Testing Predictions in Macaque

    Science.gov (United States)

    Shera, Christopher A.; Bergevin, Christopher; Kalluri, Radha; Laughlin, Myles Mc; Michelet, Pascal; van der Heijden, Marcel; Joris, Philip X.

    2013-01-01

    Otoacoustic estimates of cochlear frequency selectivity suggest substantially sharper tuning in humans. However, the logic and methodology underlying these estimates remain untested by direct measurements in primates. We report measurements of frequency tuning in macaque monkeys, Old-World primates phylogenetically closer to humans than the small laboratory animals often taken as models of human hearing (e.g., cats, guinea pigs, and chinchillas). We find that measurements of tuning obtained directly from individual nerve fibers and indirectly using otoacoustic emissions both indicate that peripheral frequency selectivity in macaques is significantly sharper than in small laboratory animals, matching that inferred for humans at high frequencies. Our results validate the use of otoacoustic emissions for noninvasive measurement of cochlear tuning and corroborate the finding of sharper tuning in humans. PMID:24701000

  16. Reseñas bibliográficas

    OpenAIRE

    Romero-Pérez, Jorge Enrique

    2014-01-01

    Se presentan las siguientes reseñas bibliográficas:      López Casal, Jury: Compendio de jurisprudencia procesal civil. Tercerías, con descripto res e índice analítico. Desde el año 2000 hasta el 2007, del Tribunal Primero Civil de San José (2008)/ Reseñado por J. Enrique Romero P.      Retana Chinchilla, Ricardo José:  Derecho marcario en Centroamérica y Panamá. Incluye Jurisprudencia de Centroamérica y Panamá (2007)/ Reseñado por J. Enrique Romero P.      Clarke, George [Director Ejecutivo]...

  17. FACTIBILIDAD DEL USO DE UN ELISA INDIRECTO PARA LA DETECCIÓN DE Glomus clarum

    Directory of Open Access Journals (Sweden)

    I. de la Providencia

    2004-01-01

    Full Text Available Este trabajo tuvo como objetivo evaluar la factibilidad del uso de un ensayo inmunoenzimático sobre soporte sólido (ELISA, para la detección de esporas de Glomus clarum. Para ello se inmunizaron conejos de la raza Chinchilla con extractos proteicos provenientes de dichas esporas. El suero policlonal obtenido de los animales inmunizados se enfrentó a G. clarum y a las esporas de otras especies de Glomales. Se logró detectar las esporas de G. clarum con el uso del ELISA indirecto a la dilución 1/3 000, sin reacciones cruzadas con las otras especies de Glomales utilizadas en este estudio a esa misma dilución.

  18. Haemophilus influenzae OxyR: characterization of its regulation, regulon and role in fitness.

    Directory of Open Access Journals (Sweden)

    Paul W Whitby

    Full Text Available To prevent damage by reactive oxygen species, many bacteria have evolved rapid detection and response systems, including the OxyR regulon. The OxyR system detects reactive oxygen and coordinates the expression of numerous defensive antioxidants. In many bacterial species the coordinated OxyR-regulated response is crucial for in vivo survival. Regulation of the OxyR regulon of Haemophilus influenzae was examined in vitro, and significant variation in the regulated genes of the OxyR regulon among strains of H. influenzae was observed. Quantitative PCR studies demonstrated a role for the OxyR-regulated peroxiredoxin/glutaredoxin as a mediator of the OxyR response, and also indicated OxyR self-regulation through a negative feedback loop. Analysis of transcript levels in H. influenzae samples derived from an animal model of otitis media demonstrated that the members of the OxyR regulon were actively upregulated within the chinchilla middle ear. H. influenzae mutants lacking the oxyR gene exhibited increased sensitivity to challenge with various peroxides. The impact of mutations in oxyR was assessed in various animal models of H. influenzae disease. In paired comparisons with the corresponding wild-type strains, the oxyR mutants were unaffected in both the chinchilla model of otitis media and an infant model of bacteremia. However, in weanling rats the oxyR mutant was significantly impaired compared to the wild-type strain. In contrast, in all three animal models when infected with a mixture of equal numbers of both wild-type and mutant strains the mutant strain was significantly out competed by the wild-type strain. These findings clearly establish a crucial role for OxyR in bacterial fitness.

  19. Haemophilus influenzae OxyR: Characterization of Its Regulation, Regulon and Role in Fitness

    Science.gov (United States)

    Whitby, Paul W.; Morton, Daniel J.; VanWagoner, Timothy M.; Seale, Thomas W.; Cole, Brett K.; Mussa, Huda J.; McGhee, Phillip A.; Bauer, Chee Yoon S.; Springer, Jennifer M.; Stull, Terrence L.

    2012-01-01

    To prevent damage by reactive oxygen species, many bacteria have evolved rapid detection and response systems, including the OxyR regulon. The OxyR system detects reactive oxygen and coordinates the expression of numerous defensive antioxidants. In many bacterial species the coordinated OxyR-regulated response is crucial for in vivo survival. Regulation of the OxyR regulon of Haemophilus influenzae was examined in vitro, and significant variation in the regulated genes of the OxyR regulon among strains of H. influenzae was observed. Quantitative PCR studies demonstrated a role for the OxyR-regulated peroxiredoxin/glutaredoxin as a mediator of the OxyR response, and also indicated OxyR self-regulation through a negative feedback loop. Analysis of transcript levels in H. influenzae samples derived from an animal model of otitis media demonstrated that the members of the OxyR regulon were actively upregulated within the chinchilla middle ear. H. influenzae mutants lacking the oxyR gene exhibited increased sensitivity to challenge with various peroxides. The impact of mutations in oxyR was assessed in various animal models of H. influenzae disease. In paired comparisons with the corresponding wild-type strains, the oxyR mutants were unaffected in both the chinchilla model of otitis media and an infant model of bacteremia. However, in weanling rats the oxyR mutant was significantly impaired compared to the wild-type strain. In contrast, in all three animal models when infected with a mixture of equal numbers of both wild-type and mutant strains the mutant strain was significantly out competed by the wild-type strain. These findings clearly establish a crucial role for OxyR in bacterial fitness. PMID:23226321

  20. Comprehensive Proteomic and Metabolomic Signatures of Nontypeable Haemophilus influenzae-Induced Acute Otitis Media Reveal Bacterial Aerobic Respiration in an Immunosuppressed Environment.

    Science.gov (United States)

    Harrison, Alistair; Dubois, Laura G; St John-Williams, Lisa; Moseley, M Arthur; Hardison, Rachael L; Heimlich, Derek R; Stoddard, Alexander; Kerschner, Joseph E; Justice, Sheryl S; Thompson, J Will; Mason, Kevin M

    2016-03-01

    A thorough understanding of the molecular details of the interactions between bacteria and host are critical to ultimately prevent disease. Recent technological advances allow simultaneous analysis of host and bacterial protein and metabolic profiles from a single small tissue sample to provide insight into pathogenesis. We used the chinchilla model of human otitis media to determine, for the first time, the most expansive delineation of global changes in protein and metabolite profiles during an experimentally induced disease. After 48 h of infection with nontypeable Haemophilus influenzae, middle ear tissue lysates were analyzed by high-resolution quantitative two-dimensional liquid chromatography-tandem mass spectrometry. Dynamic changes in 105 chinchilla proteins and 66 metabolites define the early proteomic and metabolomic signature of otitis media. Our studies indicate that establishment of disease coincides with actin morphogenesis, suppression of inflammatory mediators, and bacterial aerobic respiration. We validated the observed increase in the actin-remodeling complex, Arp2/3, and experimentally showed a role for Arp2/3 in nontypeable Haemophilus influenzae invasion. Direct inhibition of actin branch morphology altered bacterial invasion into host epithelial cells, and is supportive of our efforts to use the information gathered to modify outcomes of disease. The twenty-eight nontypeable Haemophilus influenzae proteins identified participate in carbohydrate and amino acid metabolism, redox homeostasis, and include cell wall-associated metabolic proteins. Quantitative characterization of the molecular signatures of infection will redefine our understanding of host response driven developmental changes during pathogenesis. These data represent the first comprehensive study of host protein and metabolite profiles in vivo in response to infection and show the feasibility of extensive characterization of host protein profiles during disease. Identification of

  1. Organic matter and macromineral digestibility in domestic rabbits (Oryctolagus cuniculus) as compared to other hindgut fermenters.

    Science.gov (United States)

    Hagen, K B; Tschudin, A; Liesegang, A; Hatt, J-M; Clauss, M

    2015-12-01

    It is generally assumed that animal species differ in physiological characteristics of their digestive tract. Because investigating digestive processes is often labour-intensive, requiring lengthy adaptation and collection periods, comparisons are often made on the basis of data collated from different studies. We added a new data set on dietary crude fibre (CF) and macromineral (Na, K, Ca, P, Mg) composition and apparent digestibility (aD) of organic matter (OM) and macrominerals in rabbits (Oryctolagus cuniculus; a total of 180 measurements with 12 individuals and 10 different diets) to a literature data collection for rodents and domestic horses (Equus caballus). Significant negative relationships between dietary CF and aD OM were obtained, but the significant difference in digestive efficiency between rabbits and guinea pigs (Cavia porcellus) reported from studies where both species had been investigated under identical conditions were not detectable in the larger data collection. However, the 95% confidence interval of the negative slope of the CF-aD OM relationship did not overlap between domestic horses on the one hand, and rabbits and guinea pigs on the other hand, indicating a less depressing effect of CF in horses. Akaike's information criterion indicated that aD of a macromineral did not only depend on its concentration in the diet, but also on the individual and various other diet characteristics and the presence of other macrominerals, indicating complex interactions. The data indicate similar mechanisms in the absorption of macrominerals amongst rabbits, rodents and horses, with the exception of Na and K in guinea pigs and Ca in chinchillas (Chinchilla laniger) that should be further corroborated. In particular, the occurrence of high aD Ca in hindgut fermenters, regardless of whether they employ a digestive strategy of coprophagy or whether they have fossorial habits, suggests that this peculiarity might represent an adaptation to hindgut

  2. Cell-cell junctions: a target of acoustic overstimulation in the sensory epithelium of the cochlea

    Directory of Open Access Journals (Sweden)

    Zheng Guiliang

    2012-06-01

    Full Text Available Abstract Background Exposure to intense noise causes the excessive movement of the organ of Corti, stretching the organ and compromising sensory cell functions. We recently revealed changes in the transcriptional expression of multiple adhesion-related genes during the acute phases of cochlear damage, suggesting that the disruption of cell-cell junctions is an early event in the process of cochlear pathogenesis. However, the functional state of cell junctions in the sensory epithelium is not clear. Here, we employed graded dextran-FITC, a macromolecule tracer that is impermeable to the organ of Corti under physiological conditions, to evaluate the barrier function of cell junctions in normal and noise-traumatized cochlear sensory epithelia. Results Exposure to an impulse noise of 155 dB (peak sound pressure level caused a site-specific disruption in the intercellular junctions within the sensory epithelium of the chinchilla cochlea. The most vulnerable sites were the junctions among the Hensen cells and between the Hensen and Deiters cells within the outer zone of the sensory epithelium. The junction clefts that formed in the reticular lamina were permeable to 40 and 500 but not 2,000 kDa dextran-FITC macromolecules. Moreover, this study showed that the interruption of junction integrity occurred in the reticular lamina and also in the basilar membrane, a site that had been considered to be resistant to acoustic injury. Finally, our study revealed a general spatial correlation between the site of sensory cell damage and the site of junction disruption. However, the two events lacked a strict one-to-one correlation, suggesting that the disruption of cell-cell junctions is a contributing, but not the sole, factor for initiating acute sensory cell death. Conclusions Impulse noise causes the functional disruption of intercellular junctions in the sensory epithelium of the chinchilla cochlea. This disruption occurs at an early phase of cochlear

  3. Assessment of Blood Chemistry, Weight Gain and Linear Body Measurements of Pre-Puberal Buck Rabbits Fed Different Levels of Neem (Azadirachta indica A. Juss. Leaf Meals Evaluación de Química Sanguínea, Ganancia de Peso y Mediciones Corporales Lineales de Conejos Pre-Púberes Alimentados con Diferentes Niveles de Harina de Hojas de Neem (Azadirachta indica A. Juss.

    Directory of Open Access Journals (Sweden)

    I.P Ogbuewu

    2010-09-01

    Full Text Available A 16 week feeding trial was carried out to investigate the effect of dietary Neem (Azadirachta indica A. Juss. leaf meal (NLM on body weight gain, linear body measurements and blood chemistry of pre-puberal buck rabbits. Four treatment diets were formulated to contain the NLM at inclusion levels of 0 (control, 5, 10 and 15%. Thirty six crossbred New Zealand white × Chinchilla pre-puberal buck rabbits aged 5 to 6 mo were divided into four groups of nine rabbits and each group was further replicated into three of three rabbits each. The rabbits were randomly assigned to the four dietary treatments. Lymphocyte count of rabbits fed control diet (8.32 × 10(9 mm-3 was significantly higher than the group fed 15% NLM (4.60 × 10(9 mm-3. The mean cell hemoglobin (MCH and mean cell volume (MCV of the control bucks were significantly (p 0.05 among the treatment groups. The results suggest that buck rabbits could tolerate up to 15% dietary inclusion of NLM without deleterious effects on body weight gain, linear body measurements and some hematological parameters.Se realizó un ensayo de alimentación de 16 semanas para investigar el efecto de harina de hojas de neem Azadirachta indica A. Juss. (NML sobre ganancia de peso, mediciones corporales lineales y química sanguínea de conejos machos pre-púberes. Se formularon cuatro dietas con niveles de inclusión de NLM de 0 (control, 5, 10, y 15%. Treinta y seis conejos híbridos New Zealand white × Chinchilla, pre-púberes, de 5 a 6 meses, se distribuyeron en cuatro grupos de nueve conejos, y cada grupo fue repetido en tres grupos de tres conejos cada uno. Los conejos se asignaron aleatoriamente a las cuatro dietas tratamiento. El recuento de linfocitos de los conejos alimentados con la dieta control (8,32 × 10(9 mm-3 fue significativamente mayor que el grupo alimentado con 15% NLM (4,60 × 10(9 mm-3. La hemoglobina celular media (MCH y el volumen celular medio (MCV de los conejos control fueron

  4. THE GROWTH AND REPRODUCTIVE PERFORMANCE OF DIFFERENT BREEDS OF RABBITS KEPT UNDER WARM AND HUMID ENVIRONMENTS IN GHANA

    Directory of Open Access Journals (Sweden)

    S.O. APORI

    2014-05-01

    Full Text Available The potential of rabbit production in solving the problem of inadequate animal protein supply cannot be overemphasized. A study was therefore conducted to assess the growth and reproductive performances on 488 bunnies and 87 does of Blue Vienna and 474 bunnies and 80 does of Chinchilla rabbits reared under hot and humid environment in Ghana. The reproductive performance of the two breeds, in terms of litter size at birth and weaning, litter weight at birth and weaning, kindling interval, age at first kindling and gestation length as influenced by season of kindling (rainy and dry, year of kindling (2005-2012 and parity (first to sixth and over were determined. The overall least square means for litter size at birth, bunny weight at birth, litter size at weaning, bunny weight at weaning, gestation length, kindling interval, age at first kindling, pre-weaning growth rate and post-weaning growth rate of Blue Vienna were 5.6±0.1, 51.3±0.3 g, 4.4±0.1, 601.5±0.9 g, 30.0±0.1 days, 94.7±0.4 days, 159.7±0.4 days, 13.1±0.1 g/day and 15.4±0.1 g/day respectively. Those of Chinchilla were 5.9±0.1, 54.2±0.3 g, 4.8±0.1, 601.9±0.9 g, 30.1±0.1 days, 94.6±0.3 days, 159.8±0.2 days, 13.0±0.1 g/day and 15.3±0.2 g/day respectively. Year of kindling had significant (P<0.05 effect on litter size at weaning, litter weight at kindling, gestation length, age at first kindling, post weaning growth rate, body weight at 14 weeks and mortality in both breeds. Season of birth on the other hand had significant effect (P<0.05 on litter weight at birth, gestation length and mortality in both breeds. The number of times the doe has kindled (parity significantly (P<0.05 influenced all the parameters apart from kindling interval, gestation length, age at first kindling and pre-weaning growth rate performance of both breeds. The growth performances of the breeds studied were indications of their potential of being developed in future into meat types.

  5. Protection from impulse noise induced internal ear damage by prior treatment with R-N6-phenylisopropyladenosine(R-PIA)%苯异丙腺苷(R-PIA)抗脉冲噪声所致内耳损伤的实验研究

    Institute of Scientific and Technical Information of China (English)

    刘长春; X.Y.Zheng; D.Henderson; S.L.Mcfadden; N.Hight; D.L.Ding

    2000-01-01

    目的 研究在脉冲噪声环境下苯异丙腺苷(R-N?6-phenylisopropyladenosine,R-PIA)对听觉系统损伤的预防和保护作用. 方法 6只灰鼠(chinchillas)在暴露于100个150 dB SPL脉冲噪声前2 h在其右耳用药(R-PIA 0.1 mmol/L,30 μl).脉冲噪声是模拟M-16来福枪而成. 结果 用R-PIA药物的右耳在噪声暴露后,其暂时性阈移(TTS)和永久性阈移(PTS)比仅用生理盐水的左耳少8~13 dB.其用药的右耳外、内毛细胞缺失率明显比左耳少(10%~50%、15%~45%).结论 R-PIA可有效地保护听觉系统免受脉冲噪声危害.

  6. Sensitivity of primary fibroblasts in culture to atmospheric oxygen does not correlate with species lifespan

    Science.gov (United States)

    Patrick, Alison; Seluanov, Michael; Hwang, Chaewon; Tam, Jonathan; Khan, Tanya; Morgenstern, Ari; Wiener, Lauren; Vazquez, Juan M.; Zafar, Hiba; Wen, Robert; Muratkalyeva, Malika; Doerig, Katherine; Zagorulya, Maria; Cole, Lauren; Catalano, Sophia; Lobo Ladd, Aliny AB; Coppi, A. Augusto; Coşkun, Yüksel; Tian, Xiao; Ablaeva, Julia; Nevo, Eviatar; Gladyshev, Vadim N.; Zhang, Zhengdong D.; Vijg, Jan; Seluanov, Andrei; Gorbunova, Vera

    2016-01-01

    Differences in the way human and mouse fibroblasts experience senescence in culture had long puzzled researchers. While senescence of human cells is mediated by telomere shortening, Parrinello et al. demonstrated that senescence of mouse cells is caused by extreme oxygen sensitivity. It was hypothesized that the striking difference in oxygen sensitivity between mouse and human cells explains their different rates of aging. To test if this hypothesis is broadly applicable, we cultured cells from 16 rodent species with diverse lifespans in 3% and 21% oxygen and compared their growth rates. Unexpectedly, fibroblasts derived from laboratory mouse strains were the only cells demonstrating extreme sensitivity to oxygen. Cells from hamster, muskrat, woodchuck, capybara, blind mole rat, paca, squirrel, beaver, naked mole rat and wild-caught mice were mildly sensitive to oxygen, while cells from rat, gerbil, deer mouse, chipmunk, guinea pig and chinchilla showed no difference in the growth rate between 3% and 21% oxygen. We conclude that, although the growth of primary fibroblasts is generally improved by maintaining cells in 3% oxygen, the extreme oxygen sensitivity is a peculiarity of laboratory mouse strains, possibly related to their very long telomeres, and fibroblast oxygen sensitivity does not directly correlate with species' lifespan. PMID:27163160

  7. Effects of ginkgo biloba extract on an experimental model of epilepsy

    Directory of Open Access Journals (Sweden)

    Pilija Vladimir I.

    2004-01-01

    Full Text Available INTRODUCTION The active ingredients of ginkgo biloba extracts were determined by biochemical analyses in the last ten years and they are widely used in classical medicine. The active substances of ginkgo biloba extract, mostly affect muscarinic receptors and adrenergic receptors to a lesser degree. Recently, potential effects of ginkgo biloba on NMDA receptors and on epileptogenic seizures have been considered. The main goal of this research was to investigate effects of ginkgo biloba extracts on the experimantal model of epilepsy. Material and methODS The research was carried out on chinchilla rabbits. GINGIUM solution was used with 40 mg in 1 ml of dry extract of ginkgo biloba leaves. The epileptogenic area was formed by stimulating hippocampus. Bioelectrical activity was registered 60 minutes before the epileptogenic area was formed as well as 90 minutes later. Ginkgo biloba extract was given via IM, in a single daily dose of 1ml/kg/BW. RESULTS A statistically significantly higher frequency of paroxysmal seizures was established after usage of ginkgo biloba. CONCLUSION According to the results obtained in this research, we can conclude that ginkgo biloba extracts have a proconvulsive activity.

  8. Signature-tagging of a bacterial isolate demonstrates phenotypic variability of the progeny in vivo in the absence of defined mutations

    Science.gov (United States)

    Whitby, Paul W.; VanWagoner, Timothy M.; Morton, Daniel J.; Seale, Thomas W.; Springer, Jennifer M.; Hempel, Randy J.; Stull, Terrence L.

    2012-01-01

    Awareness of the high degree of redundancy that occurs in several nutrient uptake pathways of H. influenzae led us to attempt to develop a quantitative STM method that could identify both null mutants and mutants with decreased fitness that remain viable in vivo. To accomplish this task we designed a modified STM approach that utilized a set of signature tagged wild-type (STWT) strains (in a single genetic background) as carriers for mutations in genes of interest located elsewhere in the genome. Each STWT strain differed from the others by insertion of a unique, Q-PCR-detectable, seven base pair tag into the same redundant gene locus. Initially ten STWTs were created and characterized in vitro and in vivo. As anticipated, the STWT strains were not significantly different in their in vitro growth. However, in the chinchilla model of otitis media, certain STWTs outgrew others by several orders of magnitude in mixed infections. Removal of the predominant STWT resulted in its replacement by a different predominant STWT on retesting. Unexpectedly we observed that the STWT exhibiting the greatest proliferation was animal dependent. These findings identify an inherent inability of the signature tag methodologies to accurately elucidate fitness in this animal model of infection and underscore the subtleties of H. influenzae gene regulation. PMID:23085534

  9. Ocular comparative anatomy of the family Rodentia.

    Science.gov (United States)

    Rodriguez-Ramos Fernandez, Julia; Dubielzig, Richard R

    2013-07-01

    There is little information regarding ocular anatomy and histology in many of the rodent species. Histological analyses for morphologic features were performed in 31 globes from 18 rodent species submitted to and archived at the Comparative Ocular Pathology Laboratory of Wisconsin. The following measurements were taken: thickness of the cornea, corneal epithelium, corneal stroma, Descemet's membrane, and retina. H&E sections were evaluated for the following anatomical features: presence of pigmented epithelial cells in the peripheral cornea, presence and location of Schlemm's canal, presence of iridal sphincter and dilator and ciliary body muscles, presence of pars plicata and plana, presence of retinal vessels, presence of lamina cribrosa, and presence of tapetum lucidum. The springhaas was the only rodent in our collection that presented a well-developed tapetum lucidum fibrosum. The presence of retinal vessels was variable: vessels were observed in all of the members of the mouse-related clade, except the springhaas and the beaver, in all of the squirrel-related clade members, and in none of the Ctenohystrica. In the flying squirrels, blood vessels extended to the outer limiting membrane in the photoreceptor layer. Beavers, chinchillas, capybara, and guinea pigs lacked vessels within the retina; however, they had vessels within the optic nerve head. Ground squirrels have an optic nerve head, which is linear in the horizontal plane and an asymmetric retina. The tree-dwelling squirrels have a rounded but still elongated optic nerve, and the flying squirrel has a round optic nerve head like all the other rodents.

  10. Morphological and morphometric study of the prostate of guinea pigs (Cavia porcellus, Linnaeus, 1758 during postnatal development

    Directory of Open Access Journals (Sweden)

    Adriana Gradela

    2013-11-01

    Full Text Available The prostate is clinically very important because it plays an important role in the production of sperm and fertilization of the egg, and is frequently affected by diseases, such as prostatic hyperplasia and prostate cancer. The aim of this study was to evaluate the morphology, morphometry, organo-somatic index (SOI, wall thickness and height of the prostate epithelium of guinea pigs at different stages of postnatal development. Based on the results, it was concluded that the prostate of guinea pigs resembles the prostate of Chinchilla laniger (because of similar tubulo-alveolar units, pacas and capybara (because of the presence of highly branched mucosal folds and humans (because of the secretory epithelium of the simple cubic type. The major changes observed during postnatal development were the significant increases in muscle stroma and the height of the secretory epithelium from late prepubertal until post-pubertal 1, and then a decrease in the post-pubertal 2, which was significant only for the muscle stroma. These results support the need for further studies on the postnatal development and aging of the prostate and substantiate the use of guinea pigs as an experimental model for research on this complex organ.

  11. A biphasic epigenetic switch controls immunoevasion, virulence and niche adaptation in non-typeable Haemophilus influenzae.

    Science.gov (United States)

    Atack, John M; Srikhanta, Yogitha N; Fox, Kate L; Jurcisek, Joseph A; Brockman, Kenneth L; Clark, Tyson A; Boitano, Matthew; Power, Peter M; Jen, Freda E-C; McEwan, Alastair G; Grimmond, Sean M; Smith, Arnold L; Barenkamp, Stephen J; Korlach, Jonas; Bakaletz, Lauren O; Jennings, Michael P

    2015-07-28

    Non-typeable Haemophilus influenzae contains an N(6)-adenine DNA-methyltransferase (ModA) that is subject to phase-variable expression (random ON/OFF switching). Five modA alleles, modA2, modA4, modA5, modA9 and modA10, account for over two-thirds of clinical otitis media isolates surveyed. Here, we use single molecule, real-time (SMRT) methylome analysis to identify the DNA-recognition motifs for all five of these modA alleles. Phase variation of these alleles regulates multiple proteins including vaccine candidates, and key virulence phenotypes such as antibiotic resistance (modA2, modA5, modA10), biofilm formation (modA2) and immunoevasion (modA4). Analyses of a modA2 strain in the chinchilla model of otitis media show a clear selection for ON switching of modA2 in the middle ear. Our results indicate that a biphasic epigenetic switch can control bacterial virulence, immunoevasion and niche adaptation in an animal model system.

  12. Epidemiological and clinical features of the endomyocardial form of restrictive cardiomyopathy in cats: a review of 41 cases

    Science.gov (United States)

    KIMURA, Yusuke; FUKUSHIMA, Ryuji; HIRAKAWA, Atsushi; KOBAYASHI, Masayuki; MACHIDA, Noboru

    2016-01-01

    Examination of our necropsy records for the period 2005 to 2014 yielded 41 cases of the endomyocardial form of restrictive cardiomyopathy among 327 cats with evidence of heart disease, and here, we reviewed their epidemiological and clinical features. The medical data obtained retrospectively included signalment, presenting complaints, findings of physical examination, results of various diagnostic tests, methods of treatment and survival times. Except for one Chinchilla Persian cat, all were domestic short-haired cats. The mean age at death was 7.3 ± 4.5 years (median, 6 years; range, 4 months to 19 years), and males accounted for 61% (25/41) of the total. Dyspnea was the most common clinical sign, being evident in 83% (35/41) of the cats. Hind limb paresis or paralysis due to aortic thromboembolism was evident in 41% (17/41). Arrhythmias of atrial origin were common. Echocardiography commonly revealed left atrial or biatrial enlargement with severe endocardial thickening of the left ventricle. Most of the affected cats had a poor outcome; the disease duration ranged from 1 to 977 days, and the median survival period was 30 days. PMID:26822001

  13. The ABCG2 efflux transporter from rabbit placenta: Cloning and functional characterization.

    Science.gov (United States)

    Halwachs, Sandra; Kneuer, Carsten; Gohlsch, Katrin; Müller, Marian; Ritz, Vera; Honscha, Walther

    2016-02-01

    In human placenta, the ATP-binding cassette efflux transporter ABCG2 is highly expressed in syncytiotrophoblast cells and mediates cellular excretion of various drugs and toxins. Hence, physiological ABCG2 activity substantially contributes to the fetoprotective placenta barrier function during gestation. Developmental toxicity studies are often performed in rabbit. However, despite its toxicological relevance, there is no data so far on functional ABCG2 expression in this species. Therefore, we cloned ABCG2 from placenta tissues of chinchilla rabbit. Sequencing showed 84-86% amino acid sequence identity to the orthologues from man, rat and mouse. We transduced the rabbit ABCG2 clone (rbABCG2) in MDCKII cells and stable rbABCG2 gene and protein expression was shown by RT-PCR and Western blot analysis. The rbABCG2 efflux activity was demonstrated with the Hoechst H33342 assay using the specific ABCG2 inhibitor Ko143. We further tested the effect of established human ABCG2 (hABCG2) drug substrates including the antibiotic danofloxacin or the histamine H2-receptor antagonist cimetidine on H33342 accumulation in MDCKII-rbABCG2 or -hABCG2 cells. Human therapeutic plasma concentrations of all tested drugs caused a comparable competitive inhibition of H33342 excretion in both ABCG2 clones. Altogether, we first showed functional expression of the ABCG2 efflux transporter in rabbit placenta. Moreover, our data suggest a similar drug substrate spectrum of the rabbit and the human ABCG2 efflux transporter.

  14. The Effect of Ginkgo Biloba (EGb 761 on Epileptic Activity in Rabbits

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    Vesna Vasic

    2008-10-01

    Full Text Available Different animal models are used to evaluate the process of epileptogenesis. In this investigation the kindling model of epilepsy was used. The epileptic focus was induced in Chinchilla rabbits by stimulation of the hippocampus with electric stimuli. We presumed that the extracts of Ginkgo biloba affect the formation of kindling epilepsy. Bioelectric activity of the brain was registered throughout the development of kindling with and without standardized extracts from dried ginkgo leaves (EGb 761. For each animal the following has been determined: the values of the minimum current strength necessary for the origination of threshold after-discharge (AD – discharges appearing after the cessation of stimulation; duration of the threshold AD; number of stimulations necessary for the origination of full kindling; time latency for the development of full kindling; number of spontaneous epileptogenic discharges manifested in EEG two days following the formation of full kindling during 60-minute registration. The results show that the process of epileptogenesis was influenced by EGb 761. It has been established that if the animals received EGb 761, significantly weaker minimum current strength was necessary for the development of the epileptogenic focus and the AD were longer, while the number of necessary electrostimulations for the appearance of full kindling was less and the latency was shorter.

  15. Hypothyroidism Affects Vascularization and Promotes Immune Cells Infiltration into Pancreatic Islets of Female Rabbits

    Science.gov (United States)

    Rodríguez-Castelán, Julia; Martínez-Gómez, Margarita; Castelán, Francisco; Cuevas, Estela

    2015-01-01

    Thyroidectomy induces pancreatic edema and immune cells infiltration similarly to that observed in pancreatitis. In spite of the controverted effects of hypothyroidism on serum glucose and insulin concentrations, the number and proliferation of Langerhans islet cells as well as the presence of extracellular matrix are affected depending on the islet size. In this study, we evaluated the effect of methimazole-induced hypothyroidism on the vascularization and immune cells infiltration into islets. A general observation of pancreas was also done. Twelve Chinchilla-breed female adult rabbits were divided into control (n = 6) and hypothyroid groups (n = 6, methimazole, 0.02% in drinking water for 30 days). After the treatment, rabbits were sacrificed and their pancreas was excised, histologically processed, and stained with Periodic Acid-Schiff (PAS) or Masson's Trichrome techniques. Islets were arbitrarily classified into large, medium, and small ones. The external and internal portions of each islet were also identified. Student-t-test and Mann-Whitney-U test or two-way ANOVAs were used to compare variables between groups. In comparison with control rabbits, hypothyroidism induced a strong infiltration of immune cells and a major presence of collagen and proteoglycans in the interlobular septa. Large islets showed a high vascularization and immune cells infiltration. The present results show that hypothyroidism induces pancreatitis and insulitis. PMID:26175757

  16. The ToxAvapA toxin-antitoxin locus contributes to the survival of nontypeable Haemophilus influenzae during infection.

    Science.gov (United States)

    Ren, Dabin; Kordis, Alexis A; Sonenshine, Daniel E; Daines, Dayle A

    2014-01-01

    Nontypeable Haemophilus influenzae (NTHi) is an opportunistic pathogen that is a common cause of acute and recurrent mucosal infections. One uncharacterized NTHi toxin-antitoxin (TA) module, NTHI1912-1913, is a host inhibition of growth (higBA) homologue. We hypothesized that this locus, which we designated toxAvapA, contributed to NTHi survival during infection. We deleted toxAvapA and determined that growth of the mutant in defined media was not different from the parent strain. We tested the mutant for persistence during long-term in vitro co-culture with primary human respiratory tissues, which revealed that the ΔtoxAvapA mutant was attenuated for survival. We then performed challenge studies using the chinchilla model of otitis media and determined that mutant survival was also reduced in vivo. Following purification, the toxin exhibited ribonuclease activity on RNA in vitro, while the antitoxin did not. A microarray comparison of the transcriptome revealed that the tryptophan biosynthetic regulon was significantly repressed in the mutant compared to the parent strain. HPLC studies of conditioned medium confirmed that there was no significant difference in the concentration of tryptophan remaining in the supernatant, indicating that the uptake of tryptophan by the mutant was not affected. We conclude that the role of the NTHi toxAvapA TA module in persistence following stress is multifactorial and includes effects on essential metabolic pathways.

  17. Role of the nuclease of nontypeable Haemophilus influenzae in dispersal of organisms from biofilms.

    Science.gov (United States)

    Cho, Christine; Chande, Aroon; Gakhar, Lokesh; Bakaletz, Lauren O; Jurcisek, Joseph A; Ketterer, Margaret; Shao, Jian; Gotoh, Kenji; Foster, Eric; Hunt, Jason; O'Brien, Erin; Apicella, Michael A

    2015-03-01

    Nontypeable Haemophilus influenzae (NTHI) forms biofilms in the middle ear during human infection. The biofilm matrix of NTHI contains extracellular DNA. We show that NTHI possesses a potent nuclease, which is a homolog of the thermonuclease of Staphylococcus aureus. Using a biofilm dispersal assay, studies showed a biofilm dispersal pattern in the parent strain, no evidence of dispersal in the nuclease mutant, and a partial return of dispersion in the complemented mutant. Quantitative PCR of mRNA from biofilms from a 24-h continuous flow system demonstrated a significantly increased expression of the nuclease from planktonic organisms compared to those in the biofilm phase of growth (P < 0.042). Microscopic analysis of biofilms grown in vitro showed that in the nuclease mutant the nucleic acid matrix was increased compared to the wild-type and complemented strains. Organisms were typically found in large aggregates, unlike the wild-type and complement biofilms in which the organisms were evenly dispersed throughout the biofilm. At 48 h, the majority of the organisms in the mutant biofilm were dead. The nuclease mutant formed a biofilm in the chinchilla model of otitis media and demonstrated a propensity to also form similar large aggregates of organisms. These studies indicate that NTHI nuclease is involved in biofilm remodeling and organism dispersal.

  18. Peroxiredoxin-glutaredoxin and catalase promote resistance of nontypeable Haemophilus influenzae 86-028NP to oxidants and survival within neutrophil extracellular traps.

    Science.gov (United States)

    Juneau, Richard A; Pang, Bing; Armbruster, Chelsie E; Murrah, Kyle A; Perez, Antonia C; Swords, W Edward

    2015-01-01

    Nontypeable Haemophilus influenzae (NTHI) is a common commensal and opportunistic pathogen of the human airways. For example, NTHI is a leading cause of otitis media and is the most common cause of airway infections associated with chronic obstructive pulmonary disease (COPD). These infections are often chronic/recurrent in nature and involve bacterial persistence within biofilm communities that are highly resistant to host clearance. Our previous work has shown that NTHI within biofilms has increased expression of factors associated with oxidative stress responses. The goal of this study was to define the roles of catalase (encoded by hktE) and a bifunctional peroxiredoxin-glutaredoxin (encoded by pdgX) in resistance of NTHI to oxidants and persistence in vivo. Isogenic NTHI strain 86-028NP mutants lacking hktE and pdgX had increased susceptibility to peroxide. Moreover, these strains had persistence defects in the chinchilla infection model for otitis media, as well as in a murine model for COPD. Additional work showed that pdgX and hktE were important determinants of NTHI survival within neutrophil extracellular traps (NETs), which we have shown to be an integral part of NTHI biofilms in vivo. Based on these data, we conclude that catalase and peroxiredoxin-glutaredoxin are determinants of bacterial persistence during chronic/recurrent NTHI infections that promote bacterial survival within NETs.

  19. Hypothyroidism Affects Vascularization and Promotes Immune Cells Infiltration into Pancreatic Islets of Female Rabbits

    Directory of Open Access Journals (Sweden)

    Julia Rodríguez-Castelán

    2015-01-01

    Full Text Available Thyroidectomy induces pancreatic edema and immune cells infiltration similarly to that observed in pancreatitis. In spite of the controverted effects of hypothyroidism on serum glucose and insulin concentrations, the number and proliferation of Langerhans islet cells as well as the presence of extracellular matrix are affected depending on the islet size. In this study, we evaluated the effect of methimazole-induced hypothyroidism on the vascularization and immune cells infiltration into islets. A general observation of pancreas was also done. Twelve Chinchilla-breed female adult rabbits were divided into control n=6 and hypothyroid groups (n=6, methimazole, 0.02% in drinking water for 30 days. After the treatment, rabbits were sacrificed and their pancreas was excised, histologically processed, and stained with Periodic Acid-Schiff (PAS or Masson’s Trichrome techniques. Islets were arbitrarily classified into large, medium, and small ones. The external and internal portions of each islet were also identified. Student-t-test and Mann-Whitney-U test or two-way ANOVAs were used to compare variables between groups. In comparison with control rabbits, hypothyroidism induced a strong infiltration of immune cells and a major presence of collagen and proteoglycans in the interlobular septa. Large islets showed a high vascularization and immune cells infiltration. The present results show that hypothyroidism induces pancreatitis and insulitis.

  20. Effects of St John's Wort (Hypericum perforatum L. Extracts on Epileptogenesis

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    Janka Zlinská

    2011-09-01

    Full Text Available The purpose of this study was to investigate the effects of treatment with water, n-butanol and ether extracts of Hypercom perforatum L. on epileptogenesis in rabbits. Animals from the control group received solvent-ethanol, and the kindling model of epilepsy was used. Epileptic focus was induced in Chinchilla rabbits by stimulation of the hippocampus. The following parameters were determined: the minimum current strength necessary to induce after-discharge (AD – discharges appearing after cessation of stimulation; AD duration; the number of stimulations necessary to induce spontaneous kindling; and the latency time for the development of full kindling. The results obtained indicate that epileptogenesis is influenced by Hypericum perforatum L. extract treatment. Animals treated with an ether extract of Hypericum perforatum L. required significantly weaker minimum current strengths for the development of epileptogenic focus, and displayed longer AD times, while the number of electro-stimulations necessary for full kindling was less. In contrast, animals treated with water and n-butanol extracts required increased electro-stimulations for the development of epileptic discharge, and displayed shortened AD durations versus controls.

  1. Combination of photodynamic and ultrasonic therapy for treatment of infected wounds in animal model

    Science.gov (United States)

    Menyaev, Yulian A.; Zharov, Vladimir P.

    2006-02-01

    One of the important problems of modern medicine is treatment of infected wounds. There are many diversified expedients of treatment, but none of them obey the modern physician completely. The aim of this study is to develop and test a new combined method of photodynamic ultrasonic therapy (PDUST) for treatment of infected wounds with focus on experimental trials. PDUST is based on a combination of two methods: photodynamic (PD) therapy (PDT) with photosensitizer and low frequency ultrasonic (US) therapy with antibiotic as tools for treatment of wounds and effectively killing bacteria. The main parameters are: US frequency - 26.5 kHz; US tip elongation - 40+/-20 μm wavelength of light emitting diodes (LED) array - 660+/-10 nm; light intensity on biotissue surface - 1-2 mW/cm2; photosensitizer - an aluminum disulfonated phtalocyanine dissolved in a physiological solution in concentration 10 mg/l. The experiments were carried out with 70 male chinchilla rabbits divided into 7 groups, thus the dynamics of wounds healing were studied in different modes of PDUST. The PD and US methods supplement each other and in conjunction provide additive and especially synergetic effects. The experimental data demonstrated advantages of new technology in comparison with conventional methods in cases of treatment of extended suppurative inflammatory and profound wounds. The more detailed study of PDUST method's mechanism, which is based on low intensity of LED light, PD therapy and US influence is required.

  2. Fast Waves at the Base of the Cochlea.

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    Alberto Recio-Spinoso

    Full Text Available Georg von Békésy observed that the onset times of responses to brief-duration stimuli vary as a function of distance from the stapes, with basal regions starting to move earlier than apical ones. He noticed that the speed of signal propagation along the cochlea is slow when compared with the speed of sound in water. Fast traveling waves have been recorded in the cochlea, but their existence is interpreted as the result of an experiment artifact. Accounts of the timing of vibration onsets at the base of the cochlea generally agree with Békésy's results. Some authors, however, have argued that the measured delays are too short for consistency with Békésy's theory. To investigate the speed of the traveling wave at the base of the cochlea, we analyzed basilar membrane (BM responses to clicks recorded at several locations in the base of the chinchilla cochlea. The initial component of the BM response matches remarkably well the initial component of the stapes response, after a 4-μs delay of the latter. A similar conclusion is reached by analyzing onset times of time-domain gain functions, which correspond to BM click responses normalized by middle-ear input. Our results suggest that BM responses to clicks arise from a combination of fast and slow traveling waves.

  3. THE FUNCTIONAL EFFECTIVENESS OF A CELL-ENGINEERED CONSTRUCT FOR THE REGENERATION OF ARTICULAR CARTILAGE

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    V. I. Sevastianov

    2015-01-01

    Full Text Available The aim of this study is an analysis of the functional effectiveness of a biomedical cell product consisting of a biopolymer microheterogeneous collagen-containing hydrogel (BMCH, human adipose-derived mesenchymal stromal cells (hADMSCs, and chondrogenic induction medium in the regeneration of articular cartilage. Materials and methods. The test model of the adjuvant arthritis was used (female Soviet Chinchilla rabbits with the further development into osteoarthrosis (OA combined with the clinical, biochemical, radiological, and histochemical trials. Results. On Day 92 of the OA model it has been found that the intra-articular introduction of a BMCH with hADMSCs into the left knee joint (n = 3 30 days after the OA modeling, as opposed to the right joint (negative control, n = 3, stimulates the regenerative processes of the cartilaginous tissue structure characterized by the formation of chondrocyte «columns», the emergence of isogenic groups in the intracellular matrix and the regeneration of its structure. Upon the intra-articular introduction of a BMCH (n = 3 such effects are markedly less pronounced. Conclusions. A significant regenerative potential of a cell-engineered construct of human articular tissue (CEC ATh has been proven. It is possible to presume that biostimulating properties of CEC ATh are due to the activating effect of a biomedical cell product on the stem cell migration processes from the surrounding tissue into the injured area with their subsequent differentiation. 

  4. A Comparative Study of Retinal Function in Rabbits after Panretinal Selective Retina Therapy versus Conventional Panretinal Photocoagulation

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    Young Gun Park

    2015-01-01

    Full Text Available Purpose. This study evaluates functional changes in electroretinographic findings after selective retina therapy (SRT compared to panretinal photocoagulation (PRP in rabbits. Methods. The right eyes of 12 Chinchilla rabbits received 200 laser treatment spots. The right eyes of six rabbits received SRT (SRT group, whereas the other six animals were treated using PRP on the right eye (PRP group. The eyes were investigated using full-field ERG 1 hour and 3 weeks after treatment. Histologic exam to assess the tissue response of lasers was performed on 3 weeks. Results. No significant changes in the mean ROD or CR b-wave amplitudes of the SRT lesions were evident, compared to baseline, 1 h after laser treatment (p=0.372 and 0.278, resp.. In addition, the OPs and 30 Hz flickers of the SRT lesions were not significantly altered (p=0.17 and 0.243, resp.. At 3 weeks, similar results were found. Comparing the two groups, the ROD b-wave amplitude was reduced in the PRP and SRT groups to 60.04±4.2% and 92.32±6.43% of baseline (p<0.001. Histologically, there was no visible photoreceptor alterations on week 3. Conclusions. SRT in rabbit eyes induced less functional loss than PRP in both rod-mediated retinal function and cone-mediated retinal function. In addition, SRT irradiated eyes had no functional loss compared to its control.

  5. System identification of perilymphatic fistula in an animal model

    Science.gov (United States)

    Wall, C. 3rd; Casselbrant, M. L.

    1992-01-01

    An acute animal model has been developed in the chinchilla for the study of perilymphatic fistulas. Micropunctures were made in three sites to simulate bony, round window, and oval window fistulas. The eye movements in response to pressure applied to the external auditory canal were recorded after micropuncture induction and in preoperative controls. The main pressure stimulus was a pseudorandom binary sequence (PRBS) that rapidly changed between plus and minus 200 mm of water. The PRBS stimulus, with its wide frequency bandwidth, produced responses clearly above the preoperative baseline in 78 percent of the runs. The response was better between 0.5 and 3.3 Hz than it was below 0.5 Hz. The direction of horizontal eye movement was toward the side of the fistula with positive pressure applied in 92 percent of the runs. Vertical eye movements were also observed. The ratio of vertical eye displacement to horizontal eye displacement depended upon the site of the micropuncture induction. Thus, such a ratio measurement may be clinically useful in the noninvasive localization of perilymphatic fistulas in humans.

  6. Complex noise exposures: an energy analysis.

    Science.gov (United States)

    Ahroon, W A; Hamernik, R P; Davis, R I

    1993-02-01

    Industrial noise environments usually present a complex stimulus to the exposed individual. These environments often contain mixtures of multiply reflected impact noises and a relatively Gaussian broadband noise. Noise exposure standards do not consider the possibility of interactions between the two classes of noise that can exacerbate the amount of hearing trauma. This paper presents the results of a large series of experiments designed to document the hazard posed to hearing from complex noise exposures. Twenty-three groups of chinchillas with 5 to 11 animals per group (total N = 135) were exposed for 5 days to either octave bands of noise, impacts alone, or combinations of impact and octave bands of noise. Evoked potential measures of hearing thresholds and cochleograms were used to quantify the noise-induced trauma. The results show that, for sound exposure levels (SEL) which produce less than approximately 10 dB PTS (permanent threshold shift) or 5% total sensory cell loss, equal-energy exposures tend to produce equivalent effects on hearing. However, there is a range of at least 10 dB in the SEL parameter where hearing loss from equal-energy exposures at a particular SEL can be exacerbated by increasing the repetition rate of the impacts or by the addition of a Gaussian low-level noise. The exacerbation of trauma from the addition of a Gaussian continuous noise is dependent upon the spectrum of that noise.

  7. A biphasic epigenetic switch controls immunoevasion, virulence and niche adaptation in non-typeable Haemophilus influenzae

    Science.gov (United States)

    Atack, John M.; Srikhanta, Yogitha N.; Fox, Kate L.; Jurcisek, Joseph A.; Brockman, Kenneth L.; Clark, Tyson A.; Boitano, Matthew; Power, Peter M.; Jen, Freda E.-C.; McEwan, Alastair G.; Grimmond, Sean M.; Smith, Arnold L.; Barenkamp, Stephen J.; Korlach, Jonas; Bakaletz, Lauren O.; Jennings, Michael P.

    2015-01-01

    Non-typeable Haemophilus influenzae contains an N6-adenine DNA-methyltransferase (ModA) that is subject to phase-variable expression (random ON/OFF switching). Five modA alleles, modA2, modA4, modA5, modA9 and modA10, account for over two-thirds of clinical otitis media isolates surveyed. Here, we use single molecule, real-time (SMRT) methylome analysis to identify the DNA-recognition motifs for all five of these modA alleles. Phase variation of these alleles regulates multiple proteins including vaccine candidates, and key virulence phenotypes such as antibiotic resistance (modA2, modA5, modA10), biofilm formation (modA2) and immunoevasion (modA4). Analyses of a modA2 strain in the chinchilla model of otitis media show a clear selection for ON switching of modA2 in the middle ear. Our results indicate that a biphasic epigenetic switch can control bacterial virulence, immunoevasion and niche adaptation in an animal model system. PMID:26215614

  8. The ToxAvapA toxin-antitoxin locus contributes to the survival of nontypeable Haemophilus influenzae during infection.

    Directory of Open Access Journals (Sweden)

    Dabin Ren

    Full Text Available Nontypeable Haemophilus influenzae (NTHi is an opportunistic pathogen that is a common cause of acute and recurrent mucosal infections. One uncharacterized NTHi toxin-antitoxin (TA module, NTHI1912-1913, is a host inhibition of growth (higBA homologue. We hypothesized that this locus, which we designated toxAvapA, contributed to NTHi survival during infection. We deleted toxAvapA and determined that growth of the mutant in defined media was not different from the parent strain. We tested the mutant for persistence during long-term in vitro co-culture with primary human respiratory tissues, which revealed that the ΔtoxAvapA mutant was attenuated for survival. We then performed challenge studies using the chinchilla model of otitis media and determined that mutant survival was also reduced in vivo. Following purification, the toxin exhibited ribonuclease activity on RNA in vitro, while the antitoxin did not. A microarray comparison of the transcriptome revealed that the tryptophan biosynthetic regulon was significantly repressed in the mutant compared to the parent strain. HPLC studies of conditioned medium confirmed that there was no significant difference in the concentration of tryptophan remaining in the supernatant, indicating that the uptake of tryptophan by the mutant was not affected. We conclude that the role of the NTHi toxAvapA TA module in persistence following stress is multifactorial and includes effects on essential metabolic pathways.

  9. Ultrastructural changes of chorioretinal complex under sub-threshold laser exposure at wavelengths of 0.81 and 0.532 μm (experimental study

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    N. A. Fedoruk

    2014-01-01

    Full Text Available Aim: To reveal ultrastructural changes of chorioretinal complex and their possible reversibility under sub-threshold laser exposure at wavelengths of 0.81 and 0.532 μm in 1, 8 and 30 days. Methods: Experimental study was performed on 16 chinchilla rabbits (32 eyes using laser at wavelengths of 0.532 and 0.81 μm in CW, micropulse, and transpupillary thermotherapy modes. Transmission electron microscope EM-10C (Opton, Oberkochen, Germany was used to perform ultrastructural study of retina following laser exposure. Results: In a day after sub-threshold laser exposure, ultrastructural changes were mainly detected in retinal pigment epithelium (RPE, choriocapillaries, and photoreceptors. In 8 days, intracellular regeneration of RPE and partial restoration of choriocapillary blood flow and RPE macrophages were observed. In 30 days, RPE morphology, the number and the structure of photoreceptor outer segments were re-established. Mitochondria of photoreceptor inner segments regenerated as well. Conclusion: Ultrastructural changes of chorioretinal complex following sub-threshold laser radiation were reversible. Intracellular regeneration provided almost complete recovery of chorioretinal complex structure by day 30.

  10. Ultrastructural changes of chorioretinal complex under sub-threshold laser exposure at wavelengths of 0.81 and 0.532 μm (experimental study

    Directory of Open Access Journals (Sweden)

    N. A. Fedoruk

    2015-01-01

    Full Text Available Aim: To reveal ultrastructural changes of chorioretinal complex and their possible reversibility under sub-threshold laser exposure at wavelengths of 0.81 and 0.532 μm in 1, 8 and 30 days. Methods: Experimental study was performed on 16 chinchilla rabbits (32 eyes using laser at wavelengths of 0.532 and 0.81 μm in CW, micropulse, and transpupillary thermotherapy modes. Transmission electron microscope EM-10C (Opton, Oberkochen, Germany was used to perform ultrastructural study of retina following laser exposure. Results: In a day after sub-threshold laser exposure, ultrastructural changes were mainly detected in retinal pigment epithelium (RPE, choriocapillaries, and photoreceptors. In 8 days, intracellular regeneration of RPE and partial restoration of choriocapillary blood flow and RPE macrophages were observed. In 30 days, RPE morphology, the number and the structure of photoreceptor outer segments were re-established. Mitochondria of photoreceptor inner segments regenerated as well. Conclusion: Ultrastructural changes of chorioretinal complex following sub-threshold laser radiation were reversible. Intracellular regeneration provided almost complete recovery of chorioretinal complex structure by day 30.

  11. CONTRIBUCIÓN ESPAÑOLA E IBEROAMERICANA AL ESTUDIO DEL “WORK LIFE BALANCE”: CLAVES PARA LA INTERVENCIÓN

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    Marina Romeo

    2014-01-01

    Full Text Available La actual situación de crisis económica mundial ha conllevado que nos preguntemos cómo generar ventajas competitivas que impacten en la efectividad organizacional sin que ello suponga poner en riesgo la calidad de vida de los empleados. Diversos autores en nuestro país señalan la importancia del desarrollo de políticas de salud y seguridad ocupacional (Montero, Araque, y Rey, 2009, y dentro de éstas, las relativas a políticas familiarmente responsables que favorezcan el work-life balance (WLB de sus empleados (León y Chinchilla, 2010; Urcelay, 2005. Este artículo hace una revisión de las principales aportaciones españolas e hispanoamericanas sobre el WLB en los últimos ocho años, presentando el trabajo investigador del Grupo ASH-PsicoSAO (Universidad de Barcelona en relación a este tema. El objetivo de nuestros trabajos es contribuir tanto en la esfera científica como en el ejercicio profesional, prestando especial atención al papel del supervisor.

  12. Analysis of reproductive traits of broiler rabbits reared in sub-temperate climate of Kodai hills, Tamil Nadu, India

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    S. Rajapandi

    2015-09-01

    Full Text Available Aim: The present study was carried out at Institute Rabbit Farm of Southern Regional Research Centre, Mannavanur, Kodaikanal, Tamil Nadu, India having sub-temperate climate with winter temperature during night hours going below 0°C with an objective of finding the influence of different factors such as breed, year, season and parity on different reproductive traits of broiler rabbits in order to come out with the best strategies for improving the productivity. Materials and Methods: A total of 1793 records (946 White Giant and 847 Soviet Chinchilla for weight at mating (WM, weight at kindling (WK, gestation length (GL, litter size at birth (LSB and litter size at weaning (LSW, litter weight at birth (LWB, and litter weight at weaning (LWW were collected in the period between 2000 and 2009 and the data was analyzed using general linear model option of SAS 9.2. Results: The overall mean GL, WM, WK, LSB, LSW, LWB, and LWW were 31.68±0.04 days, 3.65±0.01 kg, 3.84±0.01 kg, 6.91±0.08, 5.49±0.09, 387.62±4.07 g, and 4.66±0.07 kg, respectively. The breed has significantly influenced GL, WK, LSW, LWB, and LWW. The LSB, LSW, LWB, and LWW were 7.05±0.11, 5.76±0.13, 399.55±5.88 g, and 4.87±0.10 kg, respectively in White Giant and corresponding values for Soviet Chinchilla were 6.78±0.11, 5.22±0.12, 375.91±5.64 g, and 4.46±0.09 kg, respectively. The year of kindling had significantly affected all the reproductive traits under study and is varying over different years. The parity significantly influenced the WM, WK, and LWW. The LWW increased from first (4.16±0.21 kg to second parity (4.86±0.19 kg and remained in the same range from third parity onward. WM was significantly higher in spring season (3.72±0.02 than the animals in rainy (3.59±0.02 and winter season (3.65±0.02. Better reproductive performance in terms of higher LSB, LSW, LWB, and LWW as observed in the present study might be due to conducive environmental conditions prevailing

  13. Biología reproductiva de Convolvulus chilensis (Convolvulaceae en una población de Aucó (centro-norte de Chile Reproductive biology of Convolvulus chilensis (Convolvulaceae in a population of Aucó (north-central Chile

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    Lorena H. Suárez

    2004-12-01

    Full Text Available Convolvulus chilensis es una hierba perenne, única representante endémica de la familia Convolvulaceae en Chile. Se estudió el sistema de reproducción, fenología, morfología y longevidad floral de C. chilensis en una población natural ubicada en la localidad de Aucó, dentro de la Reserva Nacional Las Chinchillas, IV Región, Chile. Se montó un experimento de polinización controlada considerando los tratamientos de polinización natural, polinización cruzada, autopolinización manual, autopolinización automática y apomixis, evaluándose su efecto sobre la formación de frutos y el número de semillas producidas por fruto. Adicionalmente, se compararon los siguientes atributos de la progenie según tipo de polinización (autopolinización o polinización cruzada: peso de semilla, germinación, altura y número de hojas de plántulas de ocho semanas en condiciones de invernadero. Se encontró que C. chilensis es una especie autocompatible, parcialmente autógama (capaz de autopolinizarse sin mediador y parcialmente apomíctica (capaz de producir semillas sin participación de gameto masculino. La longevidad floral fue estimada en 5,25 h. Durante este período, aproximadamente en 1,5 h hay disponibilidad de polen en los estambres. El período de floración se extiende por 22 semanas (agosto a enero. El tratamiento de apomixis presentó el menor porcentaje de formación de frutos y la menor cantidad de semillas por flor en comparación a los tratamientos de polinización natural, cruzada manual, autopolinización automática y autopolinización manual, los cuales no mostraron diferencias entre sí en ambos atributos. El tipo de polinización (autopolinización o polinización cruzada no afecta el desempeño de la progenie en los atributos de semilla y plántula evaluadosThe perennial herb Convolvulus chilensis is the only endemic species of the Convolvulaceae in Chile. The breeding system, phenology, morphology and floral longevity of C

  14. A new model for non-typeable Haemophilus influenzae middle ear infection in the Junbo mutant mouse

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    Derek Hood

    2016-01-01

    Full Text Available Acute otitis media, inflammation of the middle ear, is the most common bacterial infection in children and, as a consequence, is the most common reason for antimicrobial prescription to this age group. There is currently no effective vaccine for the principal pathogen involved, non-typeable Haemophilus influenzae (NTHi. The most frequently used and widely accepted experimental animal model of middle ear infection is in chinchillas, but mice and gerbils have also been used. We have established a robust model of middle ear infection by NTHi in the Junbo mouse, a mutant mouse line that spontaneously develops chronic middle ear inflammation in specific pathogen-free conditions. The heterozygote Junbo mouse (Jbo/+ bears a mutation in a gene (Evi1, also known as Mecom that plays a role in host innate immune regulation; pre-existing middle ear inflammation promotes NTHi middle ear infection. A single intranasal inoculation with NTHi produces high rates (up to 90% of middle ear infection and bacterial titres (104-105 colony-forming units/µl in bulla fluids. Bacteria are cleared from the majority of middle ears between day 21 and 35 post-inoculation but remain in approximately 20% of middle ears at least up to day 56 post-infection. The expression of Toll-like receptor-dependent response cytokine genes is elevated in the middle ear of the Jbo/+ mouse following NTHi infection. The translational potential of the Junbo model for studying antimicrobial intervention regimens was shown using a 3 day course of azithromycin to clear NTHi infection, and its potential use in vaccine development studies was shown by demonstrating protection in mice immunized with killed homologous, but not heterologous, NTHi bacteria.

  15. Cross-axis adaptation improves 3D vestibulo-ocular reflex alignment during chronic stimulation via a head-mounted multichannel vestibular prosthesis.

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    Dai, Chenkai; Fridman, Gene Y; Chiang, Bryce; Davidovics, Natan S; Melvin, Thuy-Anh; Cullen, Kathleen E; Della Santina, Charles C

    2011-05-01

    By sensing three-dimensional (3D) head rotation and electrically stimulating the three ampullary branches of a vestibular nerve to encode head angular velocity, a multichannel vestibular prosthesis (MVP) can restore vestibular sensation to individuals disabled by loss of vestibular hair cell function. However, current spread to afferent fibers innervating non-targeted canals and otolith end organs can distort the vestibular nerve activation pattern, causing misalignment between the perceived and actual axis of head rotation. We hypothesized that over time, central neural mechanisms can adapt to correct this misalignment. To test this, we rendered five chinchillas vestibular deficient via bilateral gentamicin treatment and unilaterally implanted them with a head-mounted MVP. Comparison of 3D angular vestibulo-ocular reflex (aVOR) responses during 2 Hz, 50°/s peak horizontal sinusoidal head rotations in darkness on the first, third, and seventh days of continual MVP use revealed that eye responses about the intended axis remained stable (at about 70% of the normal gain) while misalignment improved significantly by the end of 1 week of prosthetic stimulation. A comparable time course of improvement was also observed for head rotations about the other two semicircular canal axes and at every stimulus frequency examined (0.2-5 Hz). In addition, the extent of disconjugacy between the two eyes progressively improved during the same time window. These results indicate that the central nervous system rapidly adapts to multichannel prosthetic vestibular stimulation to markedly improve 3D aVOR alignment within the first week after activation. Similar adaptive improvements are likely to occur in other species, including humans.

  16. Cochlear power flux as an indicator of mechanical activity.

    Science.gov (United States)

    Diependaal, R J; de Boer, E; Viergever, M A

    1987-09-01

    The question of whether one can conclude just from basilar membrane (BM) vibration data that the cochlea is an active mechanical system is addressed. To this end, a method is developed which computes the power flux through a channel cross section of a short-wave cochlear model from a given BM vibration pattern. The power flux is an important indicator of mechanical activity because a rise in this function corresponds to creation of mechanical energy. The power flux method is applied to BM velocity patterns as measured by Johnstone and Yates [J. Acoust. Soc. Am. 55, 584-587 (1974)] and by Sellick et al. [Hear. Res. 10, 101-108 (1983)] in the guinea pig and by Robles et al. [Peripheral Auditory Mechanisms, edited by J.B. Allen, J.L. Hall, A.E. Hubbard, S.T. Neely, and A. Tubis (Springer, New York, 1986a), pp. 121-128, and J. Acoust. Soc. Am. 80, 1364-1374 (1986b)] in the chinchilla. Before the calculations are performed, the BM data are interpolated and smoothed in order to avoid numerical errors as a result of too few and noisy data points. The choice of the smoothing method influences the computed power flux function considerably. Nevertheless, the calculations appear to make a clear distinction between the "old" data, showing broad BM tuning (Johnstone and Yates, 1974), and the "new" data, in which the response is much more peaked (Sellick et al., 1983; Robles et al., 1986a, b). The former do not give rise to a significant increase of the power flux; the latter do, although less convincingly for the Sellick et al. (1983) data than for the Robles et al. (1986a,b) data. It is thus concluded that the recently obtained, sharply tuned BM responses reflect the presence of mechanical activity in the cochlea.

  17. Survey of zoonotic dermatoses in client-owned exotic pet mammals in southern Italy.

    Science.gov (United States)

    d'Ovidio, D; Santoro, D

    2015-03-01

    Several 'exotic' mammalian species (e.g. rabbits, rodents, ferrets and hedgehogs) live in close proximity to humans as companion pets. Skin diseases (SD) are frequent causes of morbidity in exotic pet mammals, and most of those SDs have a zoonotic potential. The purpose of this study was to determine the frequencies and types of zoonotic dermatosis (ZD) in client-owned, exotic pet mammals in Southern Italy. Six-hundred and fifty-five medical records of exotic pet mammals examined between 2011 and 2012, across twenty private practice veterinary clinics around the Naples area (Italy), were retrospectively evaluated and screened for animals diagnosed with SDs (rabbits n = 455, guinea pigs n = 93, ferrets n = 64, hedgehogs n = 19, chinchillas n = 13 and rats n = 11). The records of animals diagnosed with SD, whose causative agents had a zoonotic potential, were selected for analysis. The Mann-Whitney independent test was used for statistical analysis. A P value ≤ 0.05 was considered statistically significant. Eighty-two records (12.5%) of animals with ZD were identified. Of those, 56.1% (46/82) were affected by fungal infections and 42.7% (35/82) by parasitic infections. No zoonotic bacterial or viral infections were diagnosed. Dermatophytosis was significantly diagnosed more frequently in younger animals. The results of this survey indicate that exotic pet mammals may serve as active carriers for many highly contagious pathogens with zoonotic potential. Awareness and vigilance by the veterinary practitioner is crucial in the prevention of occurrences of ZDs. Children frequently come in close contact with exotic pets. To prevent the unplanned transmission of pathogen from pet to human, an active routine screening examination and preventative treatments are strongly recommended for every newly purchased pet mammal.

  18. A new model for non-typeable Haemophilus influenzae middle ear infection in the Junbo mutant mouse.

    Science.gov (United States)

    Hood, Derek; Moxon, Richard; Purnell, Tom; Richter, Caroline; Williams, Debbie; Azar, Ali; Crompton, Michael; Wells, Sara; Fray, Martin; Brown, Steve D M; Cheeseman, Michael T

    2016-01-01

    Acute otitis media, inflammation of the middle ear, is the most common bacterial infection in children and, as a consequence, is the most common reason for antimicrobial prescription to this age group. There is currently no effective vaccine for the principal pathogen involved, non-typeable Haemophilus influenzae (NTHi). The most frequently used and widely accepted experimental animal model of middle ear infection is in chinchillas, but mice and gerbils have also been used. We have established a robust model of middle ear infection by NTHi in the Junbo mouse, a mutant mouse line that spontaneously develops chronic middle ear inflammation in specific pathogen-free conditions. The heterozygote Junbo mouse (Jbo/+) bears a mutation in a gene (Evi1, also known as Mecom) that plays a role in host innate immune regulation; pre-existing middle ear inflammation promotes NTHi middle ear infection. A single intranasal inoculation with NTHi produces high rates (up to 90%) of middle ear infection and bacterial titres (10(4)-10(5) colony-forming units/µl) in bulla fluids. Bacteria are cleared from the majority of middle ears between day 21 and 35 post-inoculation but remain in approximately 20% of middle ears at least up to day 56 post-infection. The expression of Toll-like receptor-dependent response cytokine genes is elevated in the middle ear of the Jbo/+ mouse following NTHi infection. The translational potential of the Junbo model for studying antimicrobial intervention regimens was shown using a 3 day course of azithromycin to clear NTHi infection, and its potential use in vaccine development studies was shown by demonstrating protection in mice immunized with killed homologous, but not heterologous, NTHi bacteria.

  19. Effect of meloxicam and its combination with levofloxacin, pazufloxacin, and enrofloxacin on the plasma antioxidative activity and the body weight of rabbits

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    Adil Mehraj Khan

    2013-12-01

    Full Text Available Aim: Evaluation of meloxicam, levofloxacin, pazufloxacin, and enrofloxacin for their effect on the plasma antioxidative activity (AOA and the body weight in rabbits. Materials and Methods: Thirty two male Soviet Chinchilla rabbits were divided to eight groups of four rabbits each. Group A, serving as control, was administered 5 % dextrose. Group B, C, E and G were gavaged meloxicam, levofloxacin, pazufloxacin and enrofloxacin, respectively, in 5% dextrose. Levofloxacin and pazufloxacin were administered at the dose rate of 10 mg/kg body weight b.i.d 12h, whereas the meloxicam and enrofloxacin were administered at 0.2mg/kg body weight o.i.d and 20 mg/kg body weight, respectively. Groups D, F and H were co-gavaged meloxicam with levofloxacin, pazufloxacin, and enrofloxacin, respectively, at the above dose rates. All these drugs were administered for 21 consecutive days. The plasma AOA and body weight was determined on 0, 7, 14, and 21 day of treatment.Results: The plasma AOA of meloxicam treated group was significantly lower than the control from 7th day of treatment. On the 14th day of treatment, the levofloxacin treated group had values significantly higher than the enrofloxacin-meloxicam co-treated group. Except for the levofloxacin treated group, a significant decrease in the antioxidative activity was observed in all treatment groups when compared to the control group on 21st day of treatment. The body weight of all groups differed non-significantly throughout the study period. Conclusion: The results from this study indicate that although these drugs have no effect on the body weight, a decrease in the plasma AOA is observed, especially when the duration of treatment is increased.

  20. Bio-Economic Evaluation of the Performance of Rabbits Raised under Two Different Housing Systems

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    Mobolaji-Bukola, PU.

    2002-01-01

    Full Text Available This study was conducted to evaluate the bio-economic performance of rabbits raised under two different housing systems: conventional hutch with cage system as control (A and the non-conventional floor housing system (B. Thirty six adult rabbits of medium size breed category of both sexes aged 5-6 months comprising Chinchilla (20, New Zealand White (10, Dutch (6 were used in the study which lasted 24 weeks. Fifteen does and 3 bucks were each randomly but equally assigned to both housing systems. Data on individual and group treatments were analysed with a one-way analysis of variance and students' ttest, employed in testing differences between the means. A benefit-cost analysis was used to evaluate the relative cost effectiveness of each housing option. Results obtained showed that rabbits raised on floor performed better (6 kittens < 0.05 biologically than those reared in hutched (3 kittens. For example, significant final weights (1.9 kg and weight gains (0.4 kg were observed in rabbits reared on floor as against those in hutch 1.6 kg and 0.09 kg. From an economic viewpoint, rabbits raised on floor contributed higher positive income (N 58.2 per unit of meat produced than rabbits reared in hutch or cage. Rate of return on investment in the former was estimated at about 50%. The floor housing system which is the cheaper, more productive and cost-effective is therefore recommended for farmers who are lacking the fundamental factors of production namely land and particularly capital as observed in the study location or environment.

  1. Differences in genotype and virulence among four multidrug-resistant Streptococcus pneumoniae isolates belonging to the PMEN1 clone.

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    N Luisa Hiller

    Full Text Available We report on the comparative genomics and characterization of the virulence phenotypes of four S. pneumoniae strains that belong to the multidrug resistant clone PMEN1 (Spain(23F ST81. Strains SV35-T23 and SV36-T3 were recovered in 1996 from the nasopharynx of patients at an AIDS hospice in New York. Strain SV36-T3 expressed capsule type 3 which is unusual for this clone and represents the product of an in vivo capsular switch event. A third PMEN1 isolate - PN4595-T23 - was recovered in 1996 from the nasopharynx of a child attending day care in Portugal, and a fourth strain - ATCC700669 - was originally isolated from a patient with pneumococcal disease in Spain in 1984. We compared the genomes among four PMEN1 strains and 47 previously sequenced pneumococcal isolates for gene possession differences and allelic variations within core genes. In contrast to the 47 strains - representing a variety of clonal types - the four PMEN1 strains grouped closely together, demonstrating high genomic conservation within this lineage relative to the rest of the species. In the four PMEN1 strains allelic and gene possession differences were clustered into 18 genomic regions including the capsule, the blp bacteriocins, erythromycin resistance, the MM1-2008 prophage and multiple cell wall anchored proteins. In spite of their genomic similarity, the high resolution chinchilla model was able to detect variations in virulence properties of the PMEN1 strains highlighting how small genic or allelic variation can lead to significant changes in pathogenicity and making this set of strains ideal for the identification of novel virulence determinants.

  2. Differences in genotype and virulence among four multidrug-resistant Streptococcus pneumoniae isolates belonging to the PMEN1 clone.

    Science.gov (United States)

    Hiller, N Luisa; Eutsey, Rory A; Powell, Evan; Earl, Joshua P; Janto, Benjamin; Martin, Darren P; Dawid, Suzanne; Ahmed, Azad; Longwell, Mark J; Dahlgren, Margaret E; Ezzo, Suzanne; Tettelin, Herve; Daugherty, Sean C; Mitchell, Timothy J; Hillman, Todd A; Buchinsky, Farrel J; Tomasz, Alexander; de Lencastre, Herminia; Sá-Leão, Raquel; Post, J Christopher; Hu, Fen Z; Ehrlich, Garth D

    2011-01-01

    We report on the comparative genomics and characterization of the virulence phenotypes of four S. pneumoniae strains that belong to the multidrug resistant clone PMEN1 (Spain(23F) ST81). Strains SV35-T23 and SV36-T3 were recovered in 1996 from the nasopharynx of patients at an AIDS hospice in New York. Strain SV36-T3 expressed capsule type 3 which is unusual for this clone and represents the product of an in vivo capsular switch event. A third PMEN1 isolate - PN4595-T23 - was recovered in 1996 from the nasopharynx of a child attending day care in Portugal, and a fourth strain - ATCC700669 - was originally isolated from a patient with pneumococcal disease in Spain in 1984. We compared the genomes among four PMEN1 strains and 47 previously sequenced pneumococcal isolates for gene possession differences and allelic variations within core genes. In contrast to the 47 strains - representing a variety of clonal types - the four PMEN1 strains grouped closely together, demonstrating high genomic conservation within this lineage relative to the rest of the species. In the four PMEN1 strains allelic and gene possession differences were clustered into 18 genomic regions including the capsule, the blp bacteriocins, erythromycin resistance, the MM1-2008 prophage and multiple cell wall anchored proteins. In spite of their genomic similarity, the high resolution chinchilla model was able to detect variations in virulence properties of the PMEN1 strains highlighting how small genic or allelic variation can lead to significant changes in pathogenicity and making this set of strains ideal for the identification of novel virulence determinants.

  3. Exposure and impact assessment of emissions from mercury recycling using domestic rabbits.

    Science.gov (United States)

    Reichrtová, E; Bencko, V

    1995-02-01

    A biomonitoring study using domestic rabbits (Chinchilla) aimed at the exposure and impact risks assessment of emissions released into the ambient air from a mercury-recycling plant has been carried out. Groups of rabbits were exposed to the emissions during 6 months at biomonitoring stations built up in two localities (Rudnany and Matejovce) in the distance of about 3 and 6 km around and downwind from the mercury-producing plant. The aim of the biomonitoring was to trace the translocation of inhaled inorganic Hg in body tissues and the immunotoxic impact of the emissions in the exposed mammalian organism in comparison to a non-exposed animals living outside the polluted area. The content of mercury (as a major pollutant in the ambient air in that area) in body tissues was done spectrometrically using a Trace Mercury Analyser TMA-254. Content of mercury and the other metals in the rabbits' hairs was determined by neutron activation analysis. A statistically significant increase of the inorganic Hg content in the specimens of kidneys, lungs, liver, thigh bone, heart muscle and brain was observed. Concerning the hairs, a statistically significant elevation of Hg and other elements (As, Cd, La, Zn, Na, K, W, Sr) has been found. The body tissue reaction to the increased accumulation of mercury has been investigated by a direct immunofluorescent method to search for body tissue immune complexes. The significant increase of Hg content determined in the organs (especially in kidneys and liver) of the exposed animals was also traced by the presence of immunofluorescent antibodies. In addition, the immunofluorescent antibodies in the myocardium have been proved.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Clinical Sarcocystis neurona, Sarcocystis canis, Toxoplasma gondii, and Neospora caninum infections in dogs.

    Science.gov (United States)

    Dubey, J P; Chapman, Jennifer L; Rosenthal, Benjamin M; Mense, M; Schueler, Ronald L

    2006-04-15

    Sarcocystis neurona, Sarcocystis canis, Toxoplasma gondii, and Neospora caninum are related apicomplexans that can cause systemic illness in many species of animals, including dogs. We investigated one breeder's 25 Basset Hounds for these infections. In addition, tissues from dogs and other non-canine hosts previously reported as S. canis infections were studied retrospectively. Schizonts resembling those of S. neurona, and recognized by polyclonal rabbit anti-S. neurona antibodies, were found in six of eight retrospective cases, as well as in two additional dogs (one Basset Hound, one Springer Spaniel) not previously reported. S. neurona schizonts were found in several tissues including the central nervous system, lungs, and kidneys. Fatal toxoplasmosis was diagnosed in an adult dog, and neosporosis was diagnosed in an adult and a pup related to the one diagnosed with S. neurona. No serological reactivity to S. neurona antibodies occurred when S. canis-like liver schizonts were retrospectively assayed from two dogs, a dolphin, a sea lion, a horse, a chinchilla, a black or either of two polar bears. Sequencing conserved (18S) and variable (ITS-1) portions of nuclear ribosomal DNA isolated from the schizont-laden liver of a polar bear distinguished it from all previously characterized species of Sarcocystis. We take this genetic signature as provisionally representative of S. canis, an assumption that should be tested with future sequencing of similar liver infections in other mammalian hosts. These findings further extend the uncharacteristically broad intermediate host range for S. neurona, which also causes a neurologic disease in cats, mink, raccoons, skunks, Pacific harbor seals, ponies, zebras, lynxes, and sea otters. Further work is necessary to delineate the causative agent(s) of other cases of canine sarcocystosis, and in particular to specify the attributes of S. canis, which corresponds morphologically to infections reported from wide range of terrestrial

  5. Dps promotes survival of nontypeable Haemophilus influenzae in biofilm communities in vitro and resistance to clearance in vivo

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    Bing ePang

    2012-05-01

    Full Text Available Nontypeable Haemophilus influenzae (NTHi is a common airway commensal and opportunistic pathogen that persists within surface-attached biofilm communities. In this study, we tested the hypothesis that bacterial stress-responses are activated within biofilms. Transcripts for several factors associated with bacterial resistance to environmental stress were increased in biofilm cultures as compared to planktonic cultures. Among these, a homolog of the DNA-binding protein from starved cells (dps was chosen for further study. An isogenic NTHi 86-028NP dps mutant was generated and tested for resistance to environmental stress, revealing a significant survival defects in high-iron conditions, which was mediated by oxidative stress and was restored by genetic complementation. As expected, NTHi 86-028NP dps had a general stress-response defect, exhibiting decreased resistance to many types of environmental stress. While no differences were observed in density and structure of NTHi 86-028NP and NTHi 86-028NP dps biofilms, bacterial survival was decreased in NTHi 86-028NP dps biofilms as compared to the parental strain. The role of dps persistence in vivo was tested in animal infection studies. NTHi 86-028NP dps had decreased resistance to clearance after pulmonary infection of elastase-treated mice as compared to NTHi 86-028NP, whereas minimal differences were observed in clearance from mock-treated mice. Similarly, lower numbers of NTHi 86-028NP dps were recovered from middle-ear effusions and bullar homogenates in the chinchilla model for otitis media. Therefore, we conclude that Dps promotes bacterial survival within NTHi biofilm communities both in vitro and in chronic infections in vivo.

  6. Identification and Characterization of msf, a Novel Virulence Factor in Haemophilus influenzae.

    Science.gov (United States)

    Kress-Bennett, Jennifer M; Hiller, N Luisa; Eutsey, Rory A; Powell, Evan; Longwell, Mark J; Hillman, Todd; Blackwell, Tenisha; Byers, Barbara; Mell, Joshua C; Post, J Christopher; Hu, Fen Z; Ehrlich, Garth D; Janto, Benjamin A

    2016-01-01

    Haemophilus influenzae is an opportunistic pathogen. The emergence of virulent, non-typeable strains (NTHi) emphasizes the importance of developing new interventional targets. We screened the NTHi supragenome for genes encoding surface-exposed proteins suggestive of immune evasion, identifying a large family containing Sel1-like repeats (SLRs). Clustering identified ten SLR-containing gene subfamilies, each with various numbers of SLRs per gene. Individual strains also had varying numbers of SLR-containing genes from one or more of the subfamilies. Statistical genetic analyses of gene possession among 210 NTHi strains typed as either disease or carriage found a significant association between possession of the SlrVA subfamily (which we have termed, macrophage survival factor, msf) and the disease isolates. The PittII strain contains four chromosomally contiguous msf genes. Deleting all four of these genes (msfA1-4) (KO) resulted in a highly significant decrease in phagocytosis and survival in macrophages; which was fully complemented by a single copy of the msfA1 gene. Using the chinchilla model of otitis media and invasive disease, the KO strain displayed a significant decrease in fitness compared to the WT in co-infections; and in single infections, the KO lost its ability to invade the brain. The singly complemented strain showed only a partial ability to compete with the WT suggesting gene dosage is important in vivo. The transcriptional profiles of the KO and WT in planktonic growth were compared using the NTHi supragenome array, which revealed highly significant changes in the expression of operons involved in virulence and anaerobiosis. These findings demonstrate that the msfA1-4 genes are virulence factors for phagocytosis, persistence, and trafficking to non-mucosal sites.

  7. A new model for non-typeable Haemophilus influenzae middle ear infection in the Junbo mutant mouse

    Science.gov (United States)

    Hood, Derek; Moxon, Richard; Purnell, Tom; Richter, Caroline; Williams, Debbie; Azar, Ali; Crompton, Michael; Wells, Sara; Fray, Martin; Brown, Steve D. M.; Cheeseman, Michael T.

    2016-01-01

    ABSTRACT Acute otitis media, inflammation of the middle ear, is the most common bacterial infection in children and, as a consequence, is the most common reason for antimicrobial prescription to this age group. There is currently no effective vaccine for the principal pathogen involved, non-typeable Haemophilus influenzae (NTHi). The most frequently used and widely accepted experimental animal model of middle ear infection is in chinchillas, but mice and gerbils have also been used. We have established a robust model of middle ear infection by NTHi in the Junbo mouse, a mutant mouse line that spontaneously develops chronic middle ear inflammation in specific pathogen-free conditions. The heterozygote Junbo mouse (Jbo/+) bears a mutation in a gene (Evi1, also known as Mecom) that plays a role in host innate immune regulation; pre-existing middle ear inflammation promotes NTHi middle ear infection. A single intranasal inoculation with NTHi produces high rates (up to 90%) of middle ear infection and bacterial titres (104-105 colony-forming units/µl) in bulla fluids. Bacteria are cleared from the majority of middle ears between day 21 and 35 post-inoculation but remain in approximately 20% of middle ears at least up to day 56 post-infection. The expression of Toll-like receptor-dependent response cytokine genes is elevated in the middle ear of the Jbo/+ mouse following NTHi infection. The translational potential of the Junbo model for studying antimicrobial intervention regimens was shown using a 3 day course of azithromycin to clear NTHi infection, and its potential use in vaccine development studies was shown by demonstrating protection in mice immunized with killed homologous, but not heterologous, NTHi bacteria. PMID:26611891

  8. Another one bites the dust: bite force and ecology in three caviomorph rodents (Rodentia, Hystricognathi).

    Science.gov (United States)

    Becerra, Federico; Echeverría, Alejandra Isabel; Casinos, Adrià; Vassallo, Aldo Iván

    2014-04-01

    Mammals have developed sophisticated strategies adapting to particular locomotor modes, feeding habits, and social interactions. Many rodent species have acquired a fossorial, semi-fossorial, or even subterranean life-style, converging on morphological, anatomical, and ecological features but diverging in the final arrangement. These ecological variations partially depend on the functional morphology of their digging tools. Muscular and mechanical features (e.g., lever arms relationship) of the bite force were analyzed in three caviomorph rodents with similar body size but different habits and ecological demands of the jaws. In vivo forces were measured at incisors' tip using a strain gauge load cell force transducer whereas theoretical maximal performance values, mechanical advantages, and particular contribution of each adductor muscle were estimated from dissections in specimens of Ctenomys australis (subterranean, solitary), Octodon degus (semi-fossorial, social), and Chinchilla laniger (ground-dweller, colonial). Our results showed that C. australis bites stronger than expected given its small size and C. laniger exhibited the opposite outcome, while O. degus is close to the expected value based on mammalian bite force versus body mass regressions; what might be associated to the chisel-tooth digging behavior and social interactions. Our key finding was that no matter how diverse these rodents' skulls were, no difference was found in the mechanical advantage of the main adductor muscles. Therefore, interspecific differences in the bite force might be primarily due to differences in the muscular development and force, as shown for the subterranean, solitary and territorial C. australis versus the more gracile, ground-dweller, and colonial C. laniger.

  9. Interbular space characterization in adult capybara (Hydrochoerus hydrochaeris testis

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    Tarcízio Antônio Rego de Paula

    2007-03-01

    Full Text Available This study aimed at the qualitative and quantitative characterization of the different intertubular tissue components in adult male capybara. Testes of 15 adult capybaras from a commercial slaughterhouse of wild animals were used. The average percentage of Leydig cells was 32.95 ± 10.03 %, whereas in the other components of the intertubular space it was 14.95 ± 4.79 %, thus the whole intertubular space totalized 47.91 ± 11.48 %. The average weight of the testes were 32.83 ± 4.78g, while the animals' body weight were around 52.37 kg and the gonadosomatic and leydigosomatic indexes were 0.125 ± 0.02% and 0.0411 ± 0.0148% respectively. It was concluded that the leydigosomatic index of the capybaras was lower than the one observed in rats, as well as the arrangement of the components in intertubular tissue was similar to pattern I of Fawcett's classification as was found in guinea-pigs and chinchillas.Objetivou-se com esta pesquisa caracterizar qualitativamente e quantitativamente os diferentes componentes do tecido intertubular de capivaras machos adultas. Utilizou-se testículos de 15 capivaras adultas, provenientes de um abatedouro comercial de animais silvestres. Encontrou-se um percentual médio de células de Leydig de 32,95+10,03%, dos demais componentes do espaço intertubular de 14,95+4,79% e um total de espaço intertubular de 47,91+11,48%. O peso médio dos testículos foi de 32,83+4,78g, o peso corporal dos animais foi em torno de 52,37kg e os índices gonadossomático e leydigossomático foram, respectivamente, 0,125+0,02% e 0,0411+0,0148%. Concluiu-se que o índice leydigossomático das capivaras é menor que o observado em ratos e que o arranjo dos componentes do tecido intertubular é semelhante ao descrito como padrão tipo I da classificação de Fawcett, similar ao encontrado em cobaios e chinchilas.

  10. Changes in biomechanical properties of the cornea after modified transepithelial crosslinking

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    I. B. Medvedev

    2016-01-01

    Full Text Available The aim of the study was to evaluate changes in biomechanical properties of the cornea after conducting transepithelial crosslinking with the prior application of a 40 % glucose solution.Materials and methods. Just studied the biomechanical properties of the corneas of six rabbits breed Chinchilla (12 eyes. 4 rabbit entered in the experimental group, in which in one eye glucose solution was applied on the cornea and allowed to stay for 10 minutes, followed by the instillation of 0.1 % Riboflavin solution for 30 minutes. On a couple of the rabbit eye was applied a solution of Riboflavin without prior instillation of glucose. Then carried out the procedure of irradiation according to the conventional technology with UV with a wavelength of 370 μm and a beam energy of 3.0 mW / cm2. Two rabbits (4 eyes were included in the control group, in which crosslinking was not performed. After 1 month the euthanasia of the animals was performed with subsequent enucleation for corneal research on a tensile testing machine. In the control and experimental group compared, the relaxation curves and the following parameters were analyzed: initial stress (MPa, equilibrium stress (MPa modulus of elasticity.Results and their discussion. After the crosslinking the rise of the initial stress (in the control group and 0.7+0.1 MPa, in the experimental and 1.5+0.2 1.3+0.3 MPa, respectively. The stress relaxation is fast (equilibrium stress value is reached after 250 sec. and after the administration of glucose for approximately 75 seconds, which means a greater rigidity of experimental group of samples. In the experimental groups significantly changed and the modulus of elasticity: its value has increased approximately in 2 times in comparison with control samples. The equilibrium stress values in the experimental groups were different from the zero value that also indicates a change in the chemical structure of the samples.Conclusions. Holding transepithelial of

  11. Concentration of the combined drag with antimicrobic and antiinflammatory action in rabbits eye anterior chamber at local introduction

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    I. N. Okolov

    2014-07-01

    Full Text Available Aim was to research objective consisted in an assessment of penetration of an antibacterial preparation of ciprofloxacin and a corticosteroid preparation of dexamethasone as a part of Kombinil-Duo’s combined medicinal form in moisture of the forward camera of an eye in experiment, and also in detection of the minimum overwhelmingconcentration (MOC of ciprofloxacin in VPKG for the most frequent causative agents of eye infections.Material and methods. In experiment on seven adult individuals of rabbits of breed the Chinchilla (fourteen eyes eye drops Kombinil — Duo, containing in quality of the main substance ciprofloxacin (3 mg / ml and dexamethasone(1 mg / ml are tested. Determination of concentration of the main substances of studied preparations in moisture of the eye camera carried out a method of a highly effective liquid chromatography (VEZhH in combination with mass and spectrometer detecting (MS on the liquid Shimadzu LC-20AB chromatograph with the mass and selectivedetector Shimadzu LCMS-2010EV (ESI.Results and conclusion. The maximum concentration of ciprofloxacin in moisture of the forward camera of rabbits eye made 0,25 mkg / ml, and minimum — 0,06 mkg / ml, average concentration — 0,13±0,06 mkg / ml. The anti-inflammatory component presented by dexamethasone in a studied eye form, is defined in the range from 0,14 to 0,63 mkg / ml. Average concentration of dexamethasone equaled 0,24±0,12 mkg / ml. The obtained data testify that average concentration of ciprofloxacin in VPKG exceeds average MPK90 for strains the grampolozhitelnykhof bacteria which are potential activators of postoperative infectious complications: metitsillinchuvstvitelny golden стафилококки (MPK90‑0,06 mkg / ml and ftorkhinolonchuvstvitelny koagulazonegativny стафилококки (mkg / ml MPK90–0,05. The revealed concentration are sufficient for minimization of risk of development of postoperativeinfectious complications. In

  12. RESULTS OF THE FOSFOMYCIN APPLICATION FOR THE IMPREGNATION OF BONE REPLACEMENT MATERIALS IN THE TREATMENT OF CHRONIC OSTEOMYELITIS

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    V. A. Konev

    2016-01-01

    Full Text Available Aim – to evaluate in the experimental study in vitro the duration of antimicrobial activity of fosfomycin-impregnated bone cement and to study the dynamics of radiological and morphological changes depending on the local antibiotic therapy in two-stage treatment of chronic osteomyelitis in rabbits.Materials and methods. Duration of antimicrobial activity of bone cement (depuy cmw1 gentamicin with fosfomycin in vitro was studied in comparison to cements with vancomycin and controls without additional antibiotics. Presence of the lysis zone of bacterial cultures was evaluated (Staphylococcus aureus ATCC6538 and ATCC33591, Klebsiella pneumoniae ATCC33495 and Escherichia coli ATCC25922 after application of 10 μl of the solution, collected from the cement samples after incubation for 24 hours. For the in vivo experiment, Chinchilla rabbits (n = 20 with local osteomyelitis of the tibia underwent two-stage treatment where substitution of the bone defect at stage I was performed with PMMA and stage II – with the bioresorbable material based on hydroxyapatite and triclacium phosphate (ReproBone. In an experience group (n = 10 before setting osteoreplacement materials with fosfomycin (group FOSFO, and by control (n = 10 – vancomycin (group VANCO. X-ray imaging was performed on the 1st and 21st day after installation of the cement spacer, and 45th day after substitution of the spacer with the bioresorbable material. Microbiological analysis of the samples was performed intraoperatively and on the 7th, 14th day after each stage. Histological study was conducted in both groups on the 14th, 21th day after stage I and 45th day after stage II of the treatment.Results. Maximal duration of antimicrobial activity in vitro was observed in samples of PMMA with fosfomycin whereas minimal – in control samples of gentamicin-based bone cement. Relief of the infection was attained in all animals while application of fosfomycin resulted in a more

  13. Investigation of the influence of riboflavin-UV induced crosslinking on the cornea in the experiment

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    S. I. Anisimov

    2012-01-01

    Full Text Available Purpose: Morphological examination of the efficiency of the influence of various doses of riboflavin-UV induced crosslinking on the state of the corneal stroma in experimental animals.Methods: In the work were used rabbits males breed Chinchilla mass of 1.5-2.0 kg. the experiment was conducted on 20 eyes of 10 animals, which performed the routine crosslinking. Experimental animals, depending on the power UV-laser irradiation, were divided into 4 groups: the animals of the 1 group with the minimum intensity of radiation (30 minutes, 0.27 J, animals 2 group with medium intensity of radiation (15 minutes, 0.34 J, animals 3 groups with high intensity of radiation (30 minutes, 0.34 J, the control group 4 (without UV-radiation. Date of dynamic observation of the experimental animals was 5 days, after which the animals were taken out of the experiment. Morphological investigations were carried out by means of light and electron microscopy.Results: In groups of experimental animals with the impact of riboflavin UV-radiation in the stroma of the cornea were found the appearance of the areas of cross-stitched collagen fibers and fibrils. In the zone of the crosslinking were found activated keratoblasts.Near the membranes of these cells the contents of the vacuoles are released and filaments finish building of the collagen fibers. the epithelium of the corneas of all experimental animals recovered fully, with no morphological signs of endothelial damage has been found. Electron-microscopic investigation of stroma of corneas of the experimental animals of the control group after the experiment showed the presence of keratocytes in an inactive form and collagen fibers of stroma, packed in the form of plates or beams with a characteristic orientation.Conclusion: Studies have shown that UV-irradiation of the cornea leads to the appearance of linking between the fibers of collagen and actively synthesizing cells in the stroma of the cornea, which points to a

  14. Investigation of the influence of riboflavin-UV induced crosslinking on the cornea in the experiment

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    S. I. Anisimov

    2014-07-01

    Full Text Available Purpose: Morphological examination of the efficiency of the influence of various doses of riboflavin-UV induced crosslinking on the state of the corneal stroma in experimental animals.Methods: In the work were used rabbits males breed Chinchilla mass of 1.5-2.0 kg. the experiment was conducted on 20 eyes of 10 animals, which performed the routine crosslinking. Experimental animals, depending on the power UV-laser irradiation, were divided into 4 groups: the animals of the 1 group with the minimum intensity of radiation (30 minutes, 0.27 J, animals 2 group with medium intensity of radiation (15 minutes, 0.34 J, animals 3 groups with high intensity of radiation (30 minutes, 0.34 J, the control group 4 (without UV-radiation. Date of dynamic observation of the experimental animals was 5 days, after which the animals were taken out of the experiment. Morphological investigations were carried out by means of light and electron microscopy.Results: In groups of experimental animals with the impact of riboflavin UV-radiation in the stroma of the cornea were found the appearance of the areas of cross-stitched collagen fibers and fibrils. In the zone of the crosslinking were found activated keratoblasts.Near the membranes of these cells the contents of the vacuoles are released and filaments finish building of the collagen fibers. the epithelium of the corneas of all experimental animals recovered fully, with no morphological signs of endothelial damage has been found. Electron-microscopic investigation of stroma of corneas of the experimental animals of the control group after the experiment showed the presence of keratocytes in an inactive form and collagen fibers of stroma, packed in the form of plates or beams with a characteristic orientation.Conclusion: Studies have shown that UV-irradiation of the cornea leads to the appearance of linking between the fibers of collagen and actively synthesizing cells in the stroma of the cornea, which points to a

  15. Seroprevalence of toxoplasmosis in sheep in South Africa

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    N. Abu Samraa

    2007-06-01

    Full Text Available Serum samples from 600 sheep were collected from 5 different provinces randomly chosen in South Africa. Two sheep abattoirs (representing formal slaughter of sheep and 1 rural location (representing informal slaughter of sheep per province were also selected randomly. The serum samples were tested for anti-Toxoplasma gondii IgG antibodies using 2 different serological tests : an indirect fluorescent antibody (IFA test and an enzyme-linked immunosorbent assay (ELISA test available as a commercial kit. This study provides the first published data on seroprevalence of toxoplasmosis in sheep in South Africa, although positive titres have been found previously in wild felids, ferrets, chinchillas and a dog. Data on seroprevalence in sheep is considered important because consumption of mutton is universally considered to be a source of zoonotic transfer to humans. Seroprevalence in humans in South Africa was previously found to be 20% and it is postulated that this may be linked to the informal slaughter and consumption of mutton. During this study, the overall national seroprevalence per province in sheep was found to be 5.6 % (IFA and 4.3 % (ELISA, respectively. This is lower than in other countries, possibly because South Africa has an arid climate. Differences in seroprevalence in different areas studied suggested an association with the climate and a significant correlation (P > 0.05 was detected between the prevalence of T. gondii and the minimum average temperature. The seroprevalence was found to be significantly higher (P < 0.01 in sheep originating from commercial farms (7.9 % than in rural sheep in the informal sector (3.4 %. Also, sheep managed extensively had a seroprevalence of 1.8 %, which was significantly lower (P < 0.05 than the seroprevalence in sheep under semi-intensive or intensive management systems (5.3 %. An incidental finding of interest was the considerable movement of sheep to abattoirs and mutton after slaughter. The

  16. Development and experimental basis of local subretinal technique of xenogenic’s injection stem cells labelled by magnetic perticles

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    Yu. A. Belyy

    2014-01-01

    Full Text Available Purpose: is to develop a technique for local subretinal injection of xenogeneic stem cells labeled with magnetic particles and to prove experimentally its effectiveness.Material and methods: We used a line of stem cells HEK-293 GFP,labeled with magnetic particles. The study was made on 84 eyes of 42 chinchilla rabbits 6 months of age, the weight were from 2.5 to 3.5 kg. All right eyes were experimental (42 eyes and all left eyes (42 eyes were the control group. In the experimental group we used original complex of polymer elastic magnetic implant (PEMI with laser probe and fixed it to the sclera, then we made a median vitrectomy and injected HEK-293 GFP under the retina using a specially designed dispenser. In the control group PEMI was not fixed. We examined animals using biomicroscopy, ophthalmoscopy, ultrasound scanning, optical coherence tomography  OCT, computer tomography (CT, morphological study (cryohistological sections in 1, 3, 5, 7, 14 day and 1 month after surgery.Results: According the results of biomicroscopy in observation periods up to 3 days the vascular injection was visualized in the area operation. According the results of ophthalmoscopy and ultrasound scanning in 1 day the local retinal detachment was visualized in the area of local injection of the stem cells, which was not visualized in terms of further observations. CT helped us to confirm the local place of PEMI fixation. The morphological study results showed that cells were located in the subretinal space up to 14 days in the experimental group, and only up 3 days in the control group.Conclusion: The suggested surgical technique enables to control the injection of cells into the subretinal space, reduces the risk of tissue damage and exit cells in the vitreous space. The suggested methodology allows the fixing of the cellular material in the local place of the injection and enables to predict cells`s movement.

  17. Different tissue reaction of oesophagus and diaphragm after mesh hiatoplasty. Results of an animal study

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    Rosch Raphael

    2008-04-01

    Full Text Available Abstract Background Laparoscopic mesh-reinforcement of the hiatal region in the treatment of gastroesophageal reflux disease (GERD and paraesophageal hernia (PEH reduces the risk of recurrence. However, there are still controversies about the technique of mesh placement, shape, structure and material. We therefore compared tissue integration and scar formation after implantation of two different polypropylene-meshes in a rabbit model. Methods A total of 20 female chinchilla rabbits were included in this study. Two different meshes (Polypropylene PP, Polyglecaprone 25 Composite PP-PG were implanted on the abdominal diaphragm around the oesophagus. After 3 months the implanted meshes were excised en-bloc. Histological and morphological analyses were carried out accordingly proliferation rate, apoptosis and collagen type I/III ratio. Results Regarding proliferation rate of oesophagus PP (9.31 ± 3.4% and PP-PG (13.26 ± 2.54% differ in a significant (p = 0.0097 way. In the diaphragm we found a significant (p = 0.00066 difference between PP (9.43 ± 1.45% and PP-PG (18.73 ± 5.92% respectively. Comparing oesophagus and diaphragm we could prove a significant difference within PP-PG-group (p = 0.0195. Within PP-group the difference reached no statistical significance (p = 0.88. We found analogous results regarding apoptosis. Furthermore, there is a significant (p = 0.00013 difference of collagen type I/III ratio in PP-PG (12.28 ± 0.8 compared to PP (8.44 ± 1,63 in case of oesophageal tissue. Concerning diaphragm we found a significant difference (p = 0.000099 between PP-PG (8.85 ± 0.81 and PP (6.32 ± 1.07 as well. Conclusion The histologic and morphologic characteristics after prosthetic enforcement of the hiatus in this animal model show a more distinct tissue integration using PP-PG compared to PP. Additionally, different wound healing and remodelling capability influence tissue integration of the mesh in diaphragm and oesophagus.

  18. Age-Independent Cartilage Generation for Synovium-Based Autologous Chondrocyte Implantation.

    Science.gov (United States)

    Hunziker, Ernst B; Lippuner, Kurt; Keel, Marius J B; Shintani, Nahoko

    2015-07-01

    The articular cartilage layer of synovial joints is commonly lesioned by trauma or by a degenerative joint disease. Attempts to repair the damage frequently involve the performance of autologous chondrocyte implantation (ACI). Healthy cartilage must be first removed from the joint, and then, on a separate occasion, following the isolation of the chondrocytes and their expansion in vitro, implanted within the lesion. The disadvantages of this therapeutic approach include the destruction of healthy cartilage-which may predispose the joint to osteoarthritic degeneration-the necessarily restricted availability of healthy tissue, the limited proliferative capacity of the donor cells-which declines with age-and the need for two surgical interventions. We postulated that it should be possible to induce synovial stem cells, which are characterized by high, age-independent, proliferative and chondrogenic differentiation capacities, to lay down cartilage within the outer juxtasynovial space after the transcutaneous implantation of a carrier bearing BMP-2 in a slow-release system. The chondrocytes could be isolated on-site and immediately used for ACI. To test this hypothesis, Chinchilla rabbits were used as an experimental model. A collagenous patch bearing BMP-2 in a slow-delivery vehicle was sutured to the inner face of the synovial membrane. The neoformed tissue was excised 5, 8, 11 and 14 days postimplantation for histological and histomorphometric analyses. Neoformed tissue was observed within the outer juxtasynovial space already on the 5th postimplantation day. It contained connective and adipose tissues, and a central nugget of growing cartilage. Between days 5 and 14, the absolute volume of cartilage increased, attaining a value of 12 mm(3) at the latter juncture. Bone was deposited in measurable quantities from the 11th day onwards, but owing to resorption, the net volume did not exceed 1.5 mm(3) (14th day). The findings confirm our hypothesis. The quantity of

  19. Concentration of the combined drag with antimicrobic and antiinflammatory action in rabbits eye anterior chamber at local introduction

    Directory of Open Access Journals (Sweden)

    I. N. Okolov

    2014-01-01

    Full Text Available Aim was to research objective consisted in an assessment of penetration of an antibacterial preparation of ciprofloxacin and a corticosteroid preparation of dexamethasone as a part of Kombinil-Duo’s combined medicinal form in moisture of the forward camera of an eye in experiment, and also in detection of the minimum overwhelmingconcentration (MOC of ciprofloxacin in VPKG for the most frequent causative agents of eye infections.Material and methods. In experiment on seven adult individuals of rabbits of breed the Chinchilla (fourteen eyes eye drops Kombinil — Duo, containing in quality of the main substance ciprofloxacin (3 mg / ml and dexamethasone(1 mg / ml are tested. Determination of concentration of the main substances of studied preparations in moisture of the eye camera carried out a method of a highly effective liquid chromatography (VEZhH in combination with mass and spectrometer detecting (MS on the liquid Shimadzu LC-20AB chromatograph with the mass and selectivedetector Shimadzu LCMS-2010EV (ESI.Results and conclusion. The maximum concentration of ciprofloxacin in moisture of the forward camera of rabbits eye made 0,25 mkg / ml, and minimum — 0,06 mkg / ml, average concentration — 0,13±0,06 mkg / ml. The anti-inflammatory component presented by dexamethasone in a studied eye form, is defined in the range from 0,14 to 0,63 mkg / ml. Average concentration of dexamethasone equaled 0,24±0,12 mkg / ml. The obtained data testify that average concentration of ciprofloxacin in VPKG exceeds average MPK90 for strains the grampolozhitelnykhof bacteria which are potential activators of postoperative infectious complications: metitsillinchuvstvitelny golden стафилококки (MPK90‑0,06 mkg / ml and ftorkhinolonchuvstvitelny koagulazonegativny стафилококки (mkg / ml MPK90–0,05. The revealed concentration are sufficient for minimization of risk of development of postoperativeinfectious complications. In

  20. Development and experimental basis of local subretinal technique of xenogenic’s injection stem cells labelled by magnetic perticles

    Directory of Open Access Journals (Sweden)

    Yu. A. Belyy

    2014-10-01

    Full Text Available Purpose: is to develop a technique for local subretinal injection of xenogeneic stem cells labeled with magnetic particles and to prove experimentally its effectiveness.Material and methods: We used a line of stem cells HEK-293 GFP,labeled with magnetic particles. The study was made on 84 eyes of 42 chinchilla rabbits 6 months of age, the weight were from 2.5 to 3.5 kg. All right eyes were experimental (42 eyes and all left eyes (42 eyes were the control group. In the experimental group we used original complex of polymer elastic magnetic implant (PEMI with laser probe and fixed it to the sclera, then we made a median vitrectomy and injected HEK-293 GFP under the retina using a specially designed dispenser. In the control group PEMI was not fixed. We examined animals using biomicroscopy, ophthalmoscopy, ultrasound scanning, optical coherence tomography  OCT, computer tomography (CT, morphological study (cryohistological sections in 1, 3, 5, 7, 14 day and 1 month after surgery.Results: According the results of biomicroscopy in observation periods up to 3 days the vascular injection was visualized in the area operation. According the results of ophthalmoscopy and ultrasound scanning in 1 day the local retinal detachment was visualized in the area of local injection of the stem cells, which was not visualized in terms of further observations. CT helped us to confirm the local place of PEMI fixation. The morphological study results showed that cells were located in the subretinal space up to 14 days in the experimental group, and only up 3 days in the control group.Conclusion: The suggested surgical technique enables to control the injection of cells into the subretinal space, reduces the risk of tissue damage and exit cells in the vitreous space. The suggested methodology allows the fixing of the cellular material in the local place of the injection and enables to predict cells`s movement.

  1. Angiogenesis and healing with non-shrinking, fast degradeable PLGA/CaP scaffolds in critical-sized defects in the rabbit femur with or without osteogenically induced mesenchymal stem cells.

    Science.gov (United States)

    Endres, S; Hiebl, B; Hägele, J; Beltzer, C; Fuhrmann, R; Jäger, V; Almeida, M; Costa, E; Santos, C; Traupe, H; Jung, E M; Prantl, L; Jung, F; Wilke, A; Franke, R-P

    2011-01-01

    Cost effective and safely to apply tissue engineered constructs of big volume bone transplants for the reconstruction of critical sized defects (CSD) are still not available. Key problems with synthetic scaffold materials are shrinkage and fast degradation of the scaffolds, a lack of blood supply and nutrition in the central scaffold volume and the absent or the scarce development of bone tissue along the scaffold to bridge the bone defect. The use of composite scaffolds made of biopolymers like polylactidglycolid acid (PLGA) coated and loaded with calcium phosphates (CaP) revealed promising therapeutical options for the regeneration of critical sized bone defects. In this study interconnectively macroporous PLGA scaffolds loaded with microporous and coated with nanoporous calcium phosphates were either seeded in fixed bed bioreactors with allogenic osteogenically induced mesenchymal stem cells and implanted or implanted unseeded into critical sized femoral bone defects. As CSD a 12 mm long segment of the chinchilla femur was excised where the proximal and distal parts of the femur were fixed and stabilized by the use of an eight-hole linear reconstruction plate and secured with three bicortical screws (2.7 mm diameter) on every side of the osteotomy. Aim of the study was if we could find a way to load and coat PLGA scaffolds with CaP so that shrinkage of scaffolds could be avoided, which would favour angiogenesis, blood supply and nutrition in the construct and thus avoid central necroses regularly observed so far in transplants not vascularized and which would be inhabited by cells of he bone lineage forming new bone and healing the defect. Four weeks, at least, a notable shrinkage of the scaffolds was avoided and scaffolds were practically not degraded. Both scaffolds, loaded and loaded and coated, revealed blood vessels in all parts of the implants after 4 weeks. Only in scaffolds seeded with allogenic mesenchymal stem cells the development of bridging bone

  2. - Un modelo descriptivo del sistema reproductor hembra del coipo (Myocastor coypus I: el ovario (A descriptive model of the female reproductive system of coypu (Myocastor coypus I: the ovary

    Directory of Open Access Journals (Sweden)

    Felipe, A. E.

    2005-12-01

    conformada por tejido conectivo en disposición plexiforme, en el cual las fibras se orientaron en todas direcciones. Se observaron también fibras elásticas y argentófilas. En los ejemplares estudiados fue posible identificar todos los tipos foliculares y determinar la presencia de distintos grados de atresia correspondientes a folículos en diferentes etapas de desarrollo. Los folículos en crecimiento (secundarios atrésicos se caracterizaron por el engrosamiento de la zona pelúcida, la vacuolización citoplasmática de células foliculares, picnosis, vacuolización de la teca interna y tejido conectivo de sustitución. Con respecto a las estructuras consideradas como cuerpos lúteos, pudieron establecerse y caracterizarse tres grados de desarrollo de los mismos (inicial, medio y maduro así como determinarse diferentes estadíos de regresión o atresia. Todos los ovarios del coipo contuvieron cuerpos lúteos accesorios. Los mismos se diferenciaron de los verdaderos por su menor tamaño y la persistencia de un remanente ovocitario con una zona pelúcida degenerada. El diámetro medio de estas estructuras fue de 273.44 ± 78.22 mm. Las observaciones presentadas en este trabajo indican que el ovario de coipos sexualmente maduros es semejante al de otros mamíferos como la chinchilla (Chinchilla laniger, el cobayo (Cavia sp., la casiragua (Proechimys guairae, el carpincho (Hydrochoerus hydrochaeris, la mara (Dolichotis patagonum, el aguti (Dasyprocta aguti, el puercoespín africano austral (Hystrix africaeaustralis y el puercoespín africano común (Atherurus africanus. In the present investigation mature females of coypu (Myocastor coypus were used to determine the anatomic and histomorphologic features of the ovaries. As in all mammals, the ovary was suspended from the dorsal wall of the peritoneal cavity by the mesovarium. In the studied animals, the mesovarium did not form a bursa. The ovary of the coypu is similar to the ovary of other adult hystricomorph rodents: it

  3. Water economy in rodents: evaporative water loss and metabolic water production

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    Arturo Cortés

    2000-06-01

    Full Text Available Studies on water balance in desert-dwelling granivorous rodents use evaporative water loss (EWL and metabolic water production (MWP to evaluate the efficiency of water regulation, expressed by the model Ta @ MWP = EWL, defined by an ambient temperature (Ta value at (@ which MWP/EWL = 1. Here we evaluate and apply this model (1 - r² determining water regulation efficiency, based on the energetic cost (MR to maintain water balance (WB, that is MR-WB. To test the model, EWL was measured and MWP estimated in nine species of rodents from different localities of northern and north-central Chile (II and IV Regions: Octodon degus (Od and O. lunatus (Olu (Octodontidae, Abrothrix olivaceus (Ao, A. longipilis (Al, A. andinus (Ad, Phyllotis darwini (Pd, P. rupestris (Pr, P. magister (Pm, Oligoryzomys longicaudatus (Ol (Muridae and Chinchilla lanigera (Cl (Chinchillidae. Literature information on rodents from xeric and mesic habitats was also analyzed. Results indicate that: 1 Cl has the lowest EWL (0.58 mg H2O/g h, followed by Od Para evaluar la eficiencia en la regulación hídrica de roedores granívoros desertícolas se usa la pérdida de agua por evaporación (EWL y la producción de agua metabólica (MWP, estando esta expresada por el modelo Ta @ MWP = EWL, que representa el valor de una temperatura ambiente (Ta al cual (@ MWP/EWL = 1. En este trabajo se evalua este modelo (1- r² y se estima la eficiencia en la regulación de agua basados en el costo energético (MR de mantención del balance hídrico (WB, es decir MR-WB. Se midió EWL y se estimó MWP en las siguientes nueve especies de roedores de diferente localidades del norte y centro de Chile (Regiones II y IV: Octodon degus (Od y O. lunatus (Olu (Octodontidae, Abrothrix olivaceus (Ao, A. longipilis (Al, A. andinus (Ad, Phyllotis darwini (Pd, P. rupestris (Pr, P. magister (Pm, Oligoryzomys longicaudatus (Ol (Muridae and Chinchilla lanigera (Cl (Chinchillidae. Se analizó además información de

  4. 纤维蛋白凝胶复合骨形态发生蛋白和庆大霉素缓释药物对感染性骨缺损的修复%Fibrin glue/bone morphogenetic protein complex plus slow-release gentamicin for repairing infected bone defects in rabbits

    Institute of Scientific and Technical Information of China (English)

    高秋明; 刘兴炎; 董晓萍; 葛宝丰; 白孟海; 陈克明

    2005-01-01

    背景:慢性骨髓炎临床处理较为棘手,手术常需分期进行,目前尚无好的方法予以一期修复.目的:探讨将纤维蛋白凝胶(FG)作为骨形态发生蛋白(BMP)及庆大霉素的共同载体,一期修复感染性骨缺损的可行性.设计:完全随机对照实验研究.单位:解放军兰州军区兰州总医院全军创伤骨科中心.材料:实验在兰州军区兰州总医院骨科研究所完成.对象为体质量1.9~2.4kg的48只成年健康青紫兰兔,雌雄不限,购自甘肃省兰州市生物制品研究所.干预:48只青紫兰兔,制作慢性骨髓炎模型,清创后造成胫骨近侧干骺端内侧1.5 cm长半环形骨缺损,采用3种方法进行处理:A组,植入FG,BMP和庆大霉素复合物;B组,植入FG/BMP复合物,C组,作为空白对照.主要观察指标:术后观察动物一般情况,做骨培养及细菌计数,X射线拍片及组织学检查.结果:A组感染控制及骨修复均良好,感染控制率、再生骨量明显优于B组.B,C两组在感染控制率上无显著差异.C组动物骨修复差.结论:FG,BMP及庆大霉素复合物具有促进成骨及抗感染的双重作用,可用于感染性骨缺损及污染严重的开放性损伤造成的骨缺损的修复.%BACKGROUND: Chronic osteomyelitis is difficult to manage clinically, and two or more operations were commonly needed. No satisfactory method for one-stage repair has been currently available.OBJECTIVE: To examine the possibility of using fibrin glue(FG) as the common carrier for both bone morphogenetic protein(BMP) and gentamicin for one-stage repair of infected bone defects.DESIGN: A completely randomized controlled experiment.SETTING: Center of Orthopaedic Surgery, Lanzhou General Hospital of Lanzhou Area Command of of Chinese PLA.MATERIALS: The experiment was conducted using 48 healthy adult Chinchilla rabbits of either sex on normal diet with body mass of 1.9 to 2.4 kg,provided by the Institute of Biological Products, Lanzhou, Gansu Province

  5. Experimental pleural empyema model in rabbits: Why, how and what are the next steps

    Directory of Open Access Journals (Sweden)

    Cvijanović Vlado

    2014-01-01

    Full Text Available Bacgraund/Aim. The use of new therapeutic methods to prevent development of fibrothorax as the final complication of the human pleural infections requires research with experimental animals. The aim of this study was to standardize the procedures for the establishment of our own experimental model of empyema in rabbits, since it should be able to offer similar conditions found in human pleural infections. Methods. This experiment included 15 chinchilla rabbits, weighing from 2.3 to 2.8 kg. There were 12 rabbits in the experimental group, while 3 rabbits formed the control group. On the first day, we administered 0.4-0.5 mL of turpentine in the right pleural space of the rabbits from the experimental group in order to provoke sterile exudative pleurisy. After 24 h we injected 1 mL of Staphylococcus aureus and 1 mL of Escherichia coli bacteria in the same concentration of 4.5 x 108 bacteria/mL. Thoracocentesis for the pleural fluid analysis was performed 24, 48, 72, and 96 h after bacteria instillation. In these pleural samples we estimated the number of leucocytes and the values of lactate dehydrogenase (LDH, glucose and pH in pleural fluid, as well as the presence of bacteria. We did not protect the animals with antibiotics, and on the day 7 of the experiment they were sacrificed with the lethal dose of barbiturate (iv. The lung from the empyemic side of all experimental animals and the lung of one control animal were histopathologically examined. Results. A total of 4 animals had a small amount of clear pleural fluids or there was no fluid obtained with thoracocentesis 24 and 48 h after the bacteria instillation. after the bacteria instillation. In the remaining 8 rabbits 24 h after bacteria administration the mean values (± SD of the parameters monitored were as follows: Le 34.75 ± 6.13 x 109/L, LDH 17,000 ± 4,69 U/L, glucose 1.23 ± 0.45 mmol/L, and pH 6.975 ± 0.15. The obtained values met the criteria for the evaluation of effusion as

  6. Influence of breed on postweaning litter growth and litter feed efficiency of meat rabbits%品种对肉兔断奶后窝生长性状的影响

    Institute of Scientific and Technical Information of China (English)

    张翔宇; 李丛艳; 邝良德; 郑洁; 张翠霞

    2013-01-01

    本研究旨在明确影响肉兔断奶后窝生长性状和料肉比的重要因素.利用一般线性模型分析了来自5个不同肉兔品种(新西兰白兔,加利福尼亚兔,比利时兔,青紫蓝兔和福建黄兔)的909只173窝肉兔断奶后窝生长和料肉比性状.结果表明,品种和断奶数对断奶窝重(5周龄窝重),窝增重,窝上市体重(10周龄窝重),个体平均上市体重,窝采食量和料肉比的影响极显著(P<0.01).出生月份对窝采食量影响极显著(P<0.01),对断奶窝重和窝上市体重的影响显著(P<0.05).比利时兔的断奶窝重、窝增重、窝上市体重、窝采食量和平均上市体重显著高于其他品种,而福建黄兔的上述5项指标显著低于其他品种(P<0.05).断奶数与断奶窝重、窝采食量、窝增重、窝上市体重和料肉比的回归系数为正且显著.品种、断奶数和出生月份是影响肉兔断奶后窝性状和料肉比的重要因素.本研究的结果为将比利时兔作为杂交的终端父本提供重要依据.%The major factors influencing post-weaning litter growth and litter feed efficiency were analyzed with the General Linear Model (GLM) using 909 meat rabbits, from 173 litters representing 5 breeds (New Zealand White, Californian, Flemish Giant, Chinchilla, and Fujian Yellow). Breed and number weaned per litter had a significant effect on litter weaning weight at 5 weeks, litter weight gain, litter market weight at 10 weeks, average market weight, litter feed intake, and litter feed efficiency (P<0. 01). Month of birth had a significant (P<0. 01) difference on litter feed intake and on litter weaning weight and litter market weight (P<0. 05). Litter weaning weight, litter weight gain, litter market weight and average market weight were heavier and litter feed intake was higher in Flemish Giant litters than in other breed litters (P<0. 05). However, the five traits mentioned above were lower in Fujian Yellow litters than in other breed

  7. Relation of focal hair-cell lesions to noise-exposure parameters from a 4- or a 0.5-kHz octave band of noise.

    Science.gov (United States)

    Harding, Gary W; Bohne, Barbara A

    2009-08-01

    In a previous study, we examined the relation between total energy in a noise exposure and the percentage losses of outer (OHC) and inner (IHC) hair cells in the basal and apical halves of 607 chinchilla cochleae [Harding, G.W., Bohne, B.A., 2004a. Noise-induced hair-cell loss and total exposure energy: analysis of a large data set. J. Acoust. Soc. Am. 115, 2207-2220]. The animals had been exposed continuously to either a 4-kHz octave band of noise (OBN) at 47-108 dB SPL for 0.5h-36 d, or a 0.5-kHz OBN at 65-128 dB SPL for 3.5h-433 d. Interrupted exposures were also employed with both OBNs. Post-exposure recovery times ranged from 0 to 913 days. Cluster analysis was used to separate the data into three magnitudes of damage. The data were also separated into recovery times of 0 days (acute) and >0 days (chronic) and the apical and basal halves of the organ of Corti (OC). A substantial part of these hair-cell losses occurred in focal lesions (i.e., >or=50% loss of IHCs, OHCs or both over a distance of >or=0.03 mm). This aspect of the damage from noise was not included in the previous analysis. The present analysis describes, within the same three clusters, the apex-to-base distribution of 1820 focal lesions found in 468 of 660 (71%) noise-exposed cochleae. In these cochleae, OC length in mm was converted to percent distance from the apex. The lesion data were analyzed for location in percent distance from the apex and size (mm) of the lesions. In 55 of 140 (39%) non-noise-exposed, control OCs, there were 186 focal hair-cell lesions, the characteristics of which were also determined. Focal lesions with hair-cell loss >or=50% involved predominantly OHCs, IHCs only, or both OHCs and IHCs (i.e., combined OHC-IHC lesions). The predominantly OHC and combined lesions were pooled together for the analysis. The distributions of lesion location (in percent distance from the apex), weighted by lesion size (in percent of OC length) were tallied in 2%-distance bins. In controls

  8. 检测百日咳毒素的双抗体夹心ELISA法的建立%Establishment of a double antibody sandwich ELISA method for determination of pertussis toxin

    Institute of Scientific and Technical Information of China (English)

    潘殊男; 肖詹蓉; 张霖阳; 史雨舟; 简志华; 王宇星; 李世慧; 张萍

    2012-01-01

    目的 建立白喉-破伤风-无细胞百日咳疫苗生产中百日咳毒素(pertussis toxin,PT)含量的测定方法.方法 免疫家兔制备高效价抗PT血清,纯化抗PT多克隆抗体并进行酶标记,建立双抗体夹心ELISA法并对其进行验证.结果 建立的方法在0~ 20 ng/ml PT测量区间呈现最佳线性,相关系数>0.99,且重复性好.检测百日咳丝状血凝素和黏着素,结果均为阴性,说明该法特异性良好.试验内10次、不同试验间3次测定16.0、8.0、4.0、3.0 ng/ml PT,变异系数为2.8%~9.7%,回收率为95.7%~106.0%,精密度和准确度验证均符合常规质量控制要求,定量限度为3.0 ng/ml.结论 该方法能有效检测百日咳杆菌大罐发酵过程中分泌的PT,为PT质量控制奠定了重要基础.%Objective To develop an ELISA method for quantitative determination of pertussis toxin (PT) during production of combined diphtheria,tetanus and acellular pertussis vaccine.Methods After chinchilla rabbits were immunized by PT,high titer anti-serum against PT was obtained and polyclonal antibody against PT was prepared.Then,a double antibody sandwich ELISA method was developed and verified.Results The best linearity ranged from 0 to 20 ng/ml of PT (correlation coefficient > 0.99).No cross reactions with filamentous hemagglutinin and pertactin were observed by the developed ELISA.The variation coefficients of intra-and inter-assays were 2.8%-9.7% and the recovery rates were 95.7%-106.0% when 16.0,8.0,4.0 and 3.0 ng/ml of standard PTs were determined.The quantitative limit was identified as 3.0 ng/ml.Conclusion Due to the excellent specificity,precision,and accuracy,this method can be applied to detecting PT in fermentation broth quantitatively.

  9. Evaluation of {sup 99m}Tc(CO){sub 5}I as a potential lung perfusion agent

    Energy Technology Data Exchange (ETDEWEB)

    Miroslavov, Alexander E.; Gorshkov, Nikolay I.; Lumpov, Alexander L. [Division of Radiochemical Research, Khlopin Radium Institute, 2nd Murinskii pr. 28, 194021, St Petersburg (Russian Federation); Yalfimov, Anatoly N. [Nuclear Medicine Department, Central Research Institute of Roentgenology and Radiology, Leningradskaya str. 70/4, 197000, St Petersburg (Russian Federation); Suglobov, Dmitrii N. [Division of Radiochemical Research, Khlopin Radium Institute, 2nd Murinskii pr. 28, 194021, St Petersburg (Russian Federation); Ellis, Beverley L. [Department of Nuclear Medicine, Manchester Royal Infirmary, M13 9WL Manchester (United Kingdom)], E-mail: bev.ellis@manchester.ac.uk; Braddock, Rattana; Smith, Anne-Marie [Imaging Science and Biomedical Engineering, School of Cancer and Imaging Science, Stopford Building, The University of Manchester, Oxford Road, Manchester M13 9PT (United Kingdom); Prescott, Mary C.; Lawson, Richard S. [Department of Nuclear Medicine, Manchester Royal Infirmary, M13 9WL Manchester (United Kingdom); Sharma, Harbans L. [Imaging Science and Biomedical Engineering, School of Cancer and Imaging Science, Stopford Building, The University of Manchester, Oxford Road, Manchester M13 9PT (United Kingdom)

    2009-01-15

    Introduction: The use of {sup 99m}Tc-macroggregated albumin for lung perfusion imaging is well established in nuclear medicine. However, there have been safety concerns over the use of blood-derived products because of potential contamination by infective agents, for example, Variant Creutzfeldt Jakob Disease. Preliminary work has indicated that Tc(CO){sub 5}I is primarily taken up in the lungs following intravenous administration. The aim of this study was to evaluate the biodistribution and pharmacokinetics of {sup 99m}Tc(CO){sub 5}I and its potential as a lung perfusion agent. Methods: {sup 99m}Tc(CO){sub 5}I was synthesized by carbonylation of {sup 99m}TcO{sub 4-} at 160 atm of CO at 170 deg. C in the presence of HI for 40 min. Radiochemical purity was determined by HPLC using {sup 99}Tc(CO){sub 5}I as a reference. {sup 99m}Tc(CO){sub 5}I was administered by ear-vein injection to three chinchilla rabbits, and dynamic images were acquired using a gamma camera (Siemens E-cam) over 20 min. Imaging studies were also performed with {sup 99m}Tc-labeled macroaggregated albumin ({sup 99m}Tc-MAA) and {sup 99m}TcO{sub 4-} for comparison. {sup 99m}Tc(CO){sub 5}I was administered intravenously to Sprague-Dawley rats, and tissue distribution studies were obtained at 15 min and 1 h postinjection. Comparative studies were performed using {sup 99m}Tc-MAA. Results: Radiochemical purity, assessed by HPLC, was 98%. The retention time was similar to that of {sup 99}Tc(CO){sub 5}I. The dynamic images showed that 70% of {sup 99m}Tc(CO){sub 5}I appeared promptly in the lungs and remained constant for at least 20 min. In contrast, {sup 99m}TcO{sub 4-} rapidly washed out of the lungs after administration. As expected {sup 99m}Tc-MAA showed 90% lung accumulation. The percentage of injected dose per gram of organ {+-}S.D. at 1 h for {sup 99m}Tc(CO){sub 5}I was as follows: blood, 0.22{+-}0.02; lung, 12.8{+-}2.87; liver, 0.8{+-}0.15; heart, 0.15{+-}0.01; kidney, 0.47{+-}0.08. The

  10. Efficacy of Solithromycin (CEM-101) for Experimental Otitis Media Caused by Nontypeable Haemophilus influenzae and Streptococcus pneumoniae.

    Science.gov (United States)

    Figueira, M; Fernandes, P; Pelton, S I

    2016-09-01

    Solithromycin (CEM-101) is a "fourth-generation" macrolide, as it has three binding site and is acid stable. The three binding sites confer activity against bacteria resistant to the older macrolides and ketolides, including multidrug-resistant Streptococcus pneumoniae and nontypeable Haemophilus influenzae (NTHi). The objective of this study was to evaluate solithromycin pharmacokinetics (PK), middle ear fluid (MEF) concentrations, and microbiologic efficacy in a chinchilla model of experimental otitis media (EOM) due to strains of S. pneumoniae or NTHi. Plasma PK (maximum concentration of drug in serum [Cmax] and area under the concentration-time curve from 0 to 24 h [AUC0-24]) and middle ear fluid (MEF) concentrations were determined. Isolates with specified antimicrobial susceptibility patterns were inoculated directly into the middle ear (ME). Plasma and MEF were collected for PK and MEF cultures performed to determine efficacy. Solithromycin administered at 150 mg/kg of body weight/day resulted in Cmax and AUC0-24 values of 2.2 μg/ml and 27.4 μg · h/ml in plasma and 1.7 μg/ml and 28.2 μg · h/ml in extracellular MEF on day 1. By day 3, Cmax and AUC0-24 values had increased to 4.5 μg/ml and 54 μg · h/ml in plasma and 4.8 μg/ml and 98.6 μg · h/ml in extracellular MEF. For NTHi EOM, three isolates with MIC/minimal bactericidal concentration (MBC) ratios of 0.5/1 μg/ml (isolate BCH1), 2/2 μg/ml (isolate BMC1247C), and 4/4 μg/ml (isolate BMC1213C) were selected. The MEF of >85% of animals infected with BCH1 and BMC1247C was sterilized. For NTHi BMC1213, >85% of MEF cultures remained positive. For S. pneumoniae EOM, 3 isolates with MIC/MBC ratios of 0.06/0.125 μg/ml (S. pneumoniae 331), 0.125/1 μg/ml (S. pneumoniae CP-645 [MLSB phenotype]), and 0.5/2 μg/ml (CP-712 [mefA subclass mefA resistance]) were selected. Solithromycin sterilized MEF in 100% of animals infected with S. pneumoniae 331 and S. pneumoniae CP-645. ME infection persisted in 60% of

  11. 家兔MITF基因部分外显子多态性的PCR-SSCP分析%PCR-SSCP Polymorphism of Parts of Exons in MITF Gene in Rabbit

    Institute of Scientific and Technical Information of China (English)

    何孟颉; 李挺; 王晓明; 潘雨来; 吴信生

    2012-01-01

    小眼畸形相关转录因子MITF是色素细胞的发育成熟中的重要因子,可调控酪氨酸基因家族的表达,参与黑素生成的调控,从而影响动物的毛色.本实验采用PCR-SSCP技术,检测白色獭兔、海狸色獭兔和闽西南黑兔群体中家兔MITF基因的5个外显子和部分内含子区域的多态性,结果发现,引物1、2、5、7的扩增片段均未表现出多态,在获得的大小为255 bp的引物4扩增片段中发现一个SNP (C43T)位点,在各群体中表现为3种等位基因型AA、BB、AB.测序结果表明第4外显子扩增片段的突变位于5′端的内含子区域,不影响氨基酸序列.统计结果显示,白色獭兔群体不处在哈代温伯格平衡状态(P<0.05),其余群体则均处于平衡状态.闽西南黑兔群体表现出中度多态(0.5>PIC>0.25),其余群体为低度多态.%Microphthalmia-Associtated Transcription Factor plays an important role in the growth of pigment cells,which affects the furriery colors by controling the expression of tyrosinase gene family,and participating the regulation of melanin producting.In this study,the polymorphism five exons and parts of introns of MITF gene were detected by PCR-SSCP in three rabbit populations include White Rex rabbit,Chinchilla Rex rabbit and Minxinan Black rabbit.The results indicated that the primers 1,2,5 and 7 did not display polymorphism,and a 255 bp polymorphism segment was obtained by primer 4.The polymorphism of the segment obtained by primer 4 was controlled by A and B alleles and formed three genotypes, namely AA, BB, AB.The result of cloning and sequencing showed that there was one single nucleotide mutation (C/T) at 43bp in 5'end of the extended segment, and it did not change the encoding amino acid. Statistical results showed that the MITF gene SSCP sites in White rabbite population was at Hardy-Weinberg disequilibrium (PPIC>0.25),others were of low polymorphism.

  12. Biological features of the choriocapillaries after hypocrellin B photodynamic therapy%竹红菌乙素-光动力疗法对脉络膜毛细血管影响的生物学特征

    Institute of Scientific and Technical Information of China (English)

    刘凡光; 韩丽娜; 顾瑛; 张丽; 陈红霞

    2005-01-01

    BACKGROUND:The authors' experiments of the earlier stage proved that the hypocrellin B photodynamic therapy(HB-PDT) can cause selective injuries to choriocapillaries. It is not known whether changing the therapeutic parameters would gain a different result regarding the choriocapillaries after the hypocrellin B photodynamic treatment for a month.OBJECTIVE: To observe the features of Chinchilla rabbit choriocapillaries after HB-PDT treatment and to probe into the research prospect of using HB-PDT to treat choroidal neovascularization (CNV) and of using green light as the light source for PDT.DESIGN: A single sample study.SETTING: Laser Department of the Chinese PLA General Hospital.MATERIALS: The trial was conducted at the Laser Department and the Department of Pathology of the Chinese PLA General Hospital as well as the Department of Photoelectric Engineering of Beijing University of Science and Engineering. The materials included photosensitizing agent hypocrellin B (HB), a green laser transmitter, fundus fluorescence camera and transmission electronic microscope.METHODS: The 532 nm green laser transmitter and slit-lamp microscope were connected by light fiber. Chinchilla rabbits of 2.5 to 3.5 kg was narcotized generally and HB(1. 0 mg/kg) was injected into the marginal ear vein. HB was excited with the green laser of 532 nm. The power density of the light spot on fundus was 300 mW/cm2, and the energy density 30 J/cm2. Laser was applied immediately after HB injection and the diameter of the light spot was 2 000 μm. Direct observation of retina, fluorescein fundus angiography and observation with light microscope and electronic microscope were conducted on the 1st, 7th and 28th days respectively after PDT to find the biological features of retina and the choroid.MAIN OUTCOME MEASURES: Non-selective injury of retina through direct observation of the fundus; obliteration of the choriocapillaries detected through fluorescein fundus angiography; the position and

  13. Antiradiation UV Vaccine: UV Radiation, Biological effects, lesions and medical management - immune-therapy and immune-protection.

    Science.gov (United States)

    Popov, Dmitri; Jones, Jeffrey; Maliev, Slava

    Key Words: Ultraviolet radiation,Standard Erythema Dose(SED), Minimal Erythema Dose(MED), Sun Burns, Solar Dermatitis, Sun Burned Disease, DNA Damage,Cell Damage, Antiradiation UV Vaccine, Immune-Prophylaxis of Sun Burned Diseases, Immune-Prophylaxis of Sun Burns, Immune-Therapy of Sun-Burned Disease and Sun Burns,Basal Cell Carcinoma (BCC), Squamous Cell Carcinoma (SCC), Toxic Epidermal Necrolysis(TEN). Introduction: High doses of UV generated by solar source and artificial sources create an exposure of mammals and other species which can lead to ultraviolet(UV)radiation- associated disease (including erythema, epilation, keratitis, etc.). UV radiation belongs to the non-ionizing part of the electromagnetic spectrum and ranges between 100 nm and 400 nm with 100 nm having been chosen arbitrarily as the boundary between non-ionizing and ionizing radiation, however EMR is a spectrum and UV can produce molecular ionization. UV radiation is conventionally categorized into 3 areas: UV-A (>315-400 nm),UV-B (>280-315 nm)and UV-C (>100-280 nm) [IARC,Working Group Reports,2005] An important consequence of stratospheric ozone depletion is the increased transmission of solar ultraviolet (UV)radiation to the Earth's lower atmosphere and surface. Stratospheric ozone levels have been falling, in certain areas, for the past several decades, so current surface ultraviolet-B (UV-B) radiation levels are thought to be close to their modern day maximum. [S.Madronich et al.1998] Overexposure of ultraviolet radiation a major cause of skin cancer including basal cell carcinoma (BCC), squamous cell carcinoma (SCC) { collectively referred to as “non-melanoma" skin cancer (NMSC) and melanoma as well, with skin cancers being the most common cancer in North America. [Armstrong et al. 1993, Gallagher et al. 2005] Methods and Experimental Design: Our experiments and testing of a novel UV “Antiradiation Vaccine” have employed a wide variety of laboratory animals which include : Chinchilla

  14. C群脑膜炎球菌家兔免疫血清的制备及其群特异性和相关方法专属性分析%Prearation and group specificity of rabbit antisera against group C Neisseria meningococcus and their speciality in immunological methods

    Institute of Scientific and Technical Information of China (English)

    刘方蕾; 吴兵; 侯亚莉; 杨英英; 王晶; 于旭博; 范锋锋; 孔素娟; 袁菲

    2014-01-01

    Objective To prepare rabbit antisera against group C Neisseria meningococcus and analyze their group specificity as well as the speciality of relevant methods.Methods The Chinchilla rabbits were immunized through ear marginal vein with prepared group C N.meningococcus liquid at a concentration of 8 × 109 bacteria / ml,0.5 ~ 1.0 ml for each,on Monday,Wednesday and Friday every week for 4 weeks,while boosted starting from week 6 for 3 weeks,twice a week.Serum samples were collected one week after the last immunization and determined for titer by double immunodiffusion test.The group specificity and the speciality of relevant methods were analyzed by ELISA,Western blot and rocket immunoelectrophoresis (RIE).Results The method for preparation of rabbit antisera was developed.The polysaccharide antibody titers of prepared samples ①,② and ③ were 1 ∶ 8,1 ∶ 8 and 1 ∶ 16 respectively.The prepared serum samples ① and ③,at working concentrations,met the requirement for specificity of ELISA.However,the serum sample ③ could be used as the Anti-PS serum for determination of group C meningococcal conjugate by Western blot,while no cross reaction with tetanus toxoid (TT) was observed at the detection sensitivity.The mild cross reactions of serum samples ① and ② were eliminated by pre-absorption with the corresponding antigen so as to meet the requirements for Anti-PS for determination of group C meningococcal conjugate by Western blot.All the three prepared serum samples were suitable for rocket immunoelectrophoresis (IE).Conclusion Self-produced antisera,with comparable titer with commercial one,met the requirements for group specificity of ELISA,Western blot and RIE as well as the speciality of the relevant methods,which could be used for analysis of antigenicity of polysaccharide in quality control of vaccine and during production of group C meningococcal conjugate.%目的 制备C群脑膜炎球菌家兔免疫血清,并进行群特异性和相

  15. Assessment of the biological effect of hypocrellin B in photodynamic therapy system for retina and choroid%竹红菌乙素对视网膜和脉络膜光动力学治疗系统生物学效应的评定作用

    Institute of Scientific and Technical Information of China (English)

    韩丽娜; 顾瑛; 刘凡光; 李晓松

    2004-01-01

    biological effect of domestic photosensitizer hypocrellin B (HB) PTD system on retina and choroid was accessed in our study, to explore the worthiness of further study on the prospect of HB in treating SMD.OBJECTIVE: To introduce an experimental system to perform PDT irradiation system, the determination of the photosensitivity of the photosensitizers in vitro and evaluation of the therapeutic effect of photosensitizers for the retina and choroids in vivo.DESIGN: An open trial.SETTING, MATERIALS and INTERVENTION: The trial was conducted in the Department of Laser Medicine, General Hospital of Chinese PLA. Establishment of irradiation system: a laser window was created at the slit lamp microscope, which connected with 532 nm-laser in order to make the laser and the irradiation light of the slit lamp microscope to arrive at the fundus oculi at the same time. The photosensitivity of the photosensitizer was determined primarily by Methyl-thialolyl-tetrasolium(MTT) and compared with that of BPD-MA. Using chinchilla rabbits as subjects, the system was testified by domestic photosensitizer hypocrellin B photodynamic therapy (HB-PDT), whose biological effects at the irradiated area of rabbit were evaluated by fundus observation, fluorescein angiography and light and electron microscopy examination to investigate the feasibility and reliability of our experimental system.MAIN OUTCOME MEASURES: The coupling efficiency between sbt lamp microscope and laser, in vitro photosensitivity of photosensitizer and their biological effects at the irradiated area.RESULTS: The output of the laser was stable and the coupling efficiency between the laser and laser window of the slit lamp microscope was about 60%. The photosensitivity of HB in vitro was similar to BPD-MA, and HB-PDT displayed selective therapeutic property presented by closure of the retinal and choroidal capillaries with less damage to surrounding normal retina.CONCLUSION: It is useful to decide if a new photosensitizer fit for

  16. Interventional targeting administration of Ad-p53 combined with ultrasound irradiation in rabbit models of hepatic VX2 tumors%介入导入Ad-p53基因联合超声辐照治疗兔VX2肝癌

    Institute of Scientific and Technical Information of China (English)

    齐劲松; 杨瑞民; 赵鹏; 张铭秋; 崔红凯

    2013-01-01

    Objective To observe the effect of interventional targeting administration of Ad-p53 combined with ultrasound irradiation in rabbit models of hepatic VX2 tumors, as well as its impact on VEGF and MMP2. Methods Forty-two Chinchilla rabbits were collected and VX2 cancer cells were injected into the left lobe of liver on the observation in rabbits. The growth of cancer was monitored by ultrasound. Thirty rabbit models were successfully made and divided into 3 groups (each n=10) randomly. Fourteen days after transplantation of cancer cells, Ad-p53 was administrated through hepatic artery (in Ad-p53 group) or combined with ultrasound wave irradiation (in Ad-p53 + US group), while the same amount of saline was given for rabbits in control group. Three days later, the tumor size was observed with ultrasound, and then all rabbits were sacrificed, the serum VEGF level was measured by ELISA, the hepatic tissue expression of p53, MMP2 and VEGF were detected respectively by immunohistochemistry, and expression level of wild type p53 was measured using Western blot. Results No difference of tumor size was found between 3 groups before therapy. All tumor sizes increased, but the tumors in Ad-p53 + US group were relatively smaller. The efficiency of Ad-p53 transfection was improved in Ad-p53 group compared with control group, which was the highest in Ad-p53 + US group. Furthermore, the serum VEGF level decreased in Ad-p53 + US group, so did the expression of MMP2 and VEGF in Ad-p53 group and Ad-p53 + US group, more obviously in Ad-p53 + US group. Conclusion Ad-p53 can suppress the growth of hepatic VX2 tumors in rabbit models. The therapeutic efficacy of Ad-p53 can be improved by interventional targeting administration combining with ultrasound irradiation.%目的 探讨介入导向下联合超声辐照对兔VX2肝癌模型Ad-p53转染效率及该基因对VEGF、MMP2的影响.方法 青紫蓝兔42只,直视下手术,将VX2肿瘤细胞种植于肝左叶,以超声检测

  17. 不同品种肉兔断奶后生长性状的比较%Comparison of Postweaning Growth of Different Meat Rabbit Breeds

    Institute of Scientific and Technical Information of China (English)

    张翔宇; 谢晓红; 黄邓萍; 雷岷; 李金良; 杨锐; 肖嵩扬

    2012-01-01

    [Objective] The objective of the present study was to compare different purebred rabbits based on individual body growth traits and evaluate the germplasm. [Method] Postweaning data of 909 rabbits from 173 litters representing five breeds, Flemish Giant, New Zealand White, Californian, Chinchilla, Fujian Yellow, were compared for individual growth traits such as body weights at 5 (5WT), 6 (6WT), 7 (WT), 8 (WT), 9 (WT), and 10 (10WT) weeks of age, and post-weaning average daily gain between 5 and 10 weeks of age (ADG), and approximate age at market weight (AGE). The model included main effects of breed type, month of birth of the litter, parity of dam, sex, random effect of litter, litter size at weaning and age at weighting as linear covariate, and the random error. [Result] The overall means for 5WT, 6WT, 7WT, 8WT, 9WT, 10WT, ADG, AGE were 619.46 g, 791.57 g, 941.51 g, 1 107.51 g, 1 309.51 g, 1 445.52 g, 23.64 g·d-1 and 103.14 d. Significant sources of variation for individual growth traits were breed and number weaned per litter. The Flemish Giant had heavier body weights in all weeks than the other four breeds (P<0.05). However, the Fujian Yellow had lower body weights in all weeks than the other four breeds (P<0.05). Common litter variance explained a significantly large proportion of total phenotypic variance, with the proportions ranging between 0.48 and 0.74. [ Conclusion ] This result would lead us to use Flemish Giant as a terminal sire breed because of its better growth rates. A multi-trait selection index with the inclusion of both number weaned per litter and growth traits was used as the criterion of selecting the lines of meat rabbits.%[目的]比较不同肉兔品种断奶后的生长性能,并进行种质评估.[方法]分别分析了弗朗德巨兔、新西兰白兔、加利福尼亚兔、青紫蓝兔和福建黄兔的5、6、7、8、9和10周龄体重,平均日增重和上市日龄.断奶后生长数据来自上述5个品种的173

  18. Editorial

    Directory of Open Access Journals (Sweden)

    Carolina Santamaria Ulloa

    2013-07-01

    muestran estudiantes y docentes de un colegio en Costa Rica, y concluyen que tanto estudiantes como docentes tienen nociones limitadas al respecto. Chamizo, por su parte, presenta un estudio exploratorio de las muertes violentas en Costa Rica. El autor concluye que el grupo de 15 a 34 años es el más afectado por las muertes violentas y que las zonas fronterizas y costeras son las que presentan mayor riesgo.Nuestra sección de documentos históricos reproduce un trabajo elaborado hace más de 25 años por Víctor Gómez, catedrático pensionado de la Universidad de Costa Rica. Patricia Delvó hace una semblanza y una breve presentación de este trabajo que analiza la baja en la fecundidad en Costa Rica durante los años sesenta y principios de los setentas.Les invito a leer este nuevo número y aprovecho para expresarles que recibo del ahora director de Población y Salud en Mesoamérica, Ricardo Chinchilla Arley, la función editora de nuestra revista. Asumo con el compromiso de mantener la calidad y rigurosidad científica que a lo largo de 10 años ha forjado el prestigio del que hoy nos enorgullecemos. Gracias a los autores por elegirnos para publicar sus investigaciones y a ustedes, lectores, por mantenernos vigentes.

  19. Effect of Heat Reinforcing Acupuncture Manipulation on Articular Synovium LDH, SDH and CCO in Rheumatoid Arthritis ;Rabbits%热补针法对类风湿关节炎家兔关节滑膜LDH、SDH和CCO活性的影响

    Institute of Scientific and Technical Information of China (English)

    杜小正; 王金海; 秦晓光; 方晓丽; 张小江

    2016-01-01

    平补平泻组和捻转补法组(P<0.05)。结论热补针法治疗RA疗效确切,可增强RA模型家兔SDH、CCO活性,从而增强有氧代谢,使机体局部产生更多的能量,这可能是热补针法“取热”的可能机制之一。%Objective To investigate the regulating effect of heat reinforcing acupuncture manipulation on body energy metabolism enzymes in rheumatoid arthritis (RA) and preliminarily explain the mechanism of heat-producing action of heat reinforcing acupuncture manipulation. Method Forty chinchilla rabbits were randomized into normal, model, equal reinforcement and reduction, twirling reinforcement, and heat reinforcing acupuncture manipulation groups. A model of cold syndrome-type RA was made by ovalbumin induction and exposure to low temperature in the other four groups not including the normal group. From two days after successful model making, the normal and model groups were grabbed and fastened (bound) by the same way as for the acupuncture groups, 30 min once daily. The equal reinforcement and reduction group received even reinforcing-reducing method;the twirling reinforcement group, twirling reinforcement method;the heat reinforcing group, heat reinforcing acupuncture manipulation. The needle was manipulated for 1 min and retained for 30 min once daily, for a total of seven days. The RA rabbit knee joint circumference was measured and the inflammation score was recorded according to synovial histopathological sections before and after treatment. After the completion of intervention, the rabbits were sacrificed and the articular synovium was rapidly separated for frozen sections. Articular synovium lactate dehydrogenase (LDH), succinate dehydrogenase (SDH) and cytochrome oxidase (CCO) activities were measured by histochemical staining. Result After acupuncture intervention, the RA rabbit knee joint circumference was shortened in all the equal reinforcement and reduction, twirling reinforcement, and heat reinforcing acupuncture

  20. Programa de Pós-Graduação em Geologia - Dissertações Defendidas 2001 - Mestrado - Instituto de Geociências - Universidade Federal do Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    2001-01-01

    o João del Rei (Minas Gerais. Estas rochas metabasálticas - que hospedam uma série de corpos metaplutônicos, na maioria das vezes de idade paleoproterozóica -, apesar de sua íntima proximidade com as rochas do GBB, com as quais exibem um contato brusco e, aparentemente, controlado por falha, caracteristicamente, não apresentam associadas rochas vulcânicas ultramáficas e sedimentares metamorfisadas. No entanto, apesar deste, localmente, forte contraste na litologia, os dados mais significativos neste estudo mostram que a fácies anfibolito baixo a médio e a paragênese retrógrada de fácies xisto verde alto, presentes nessas rochas metabasálticas estão intimamente correlacionadas, assim como, temporalmente relacio- 42 Anuário do Instituto de Geociências - UFRJ Volume 24 / 2001 nadas àquelas encontradas nos anfibolitos associados com rochas metassedimentares e metakomatiíticas do GBB, não muito distantes da área deste trabalho. Isso, portanto, favorece a conclusão de que as rochas metabasálticas em questão devem, também, ser pensadas nesta área como parte do Greenstone Belt Barbacena. Nome: Ana Marina Escobar Castro Orientador: Maria Dolores Wanderley e Rogério Loureiro Antunes Título: Bioestratigrafia dos nanofósseis da formação mata, cretáceo médio da margem continental norte de Cuba Resumo: O grupo de nanoplâncton calcário tem sido pouco estudado em Cuba, não existindo até o mo-mento trabalhos bioestratigráficos com base neste grupo algálico. Com o objetivo de caracterizar os sedimentos do Cretáceo médio foi feito um estudo baseado em nanofósseis, integrado com dados geoquímicos. Foram examinados, para esse propósito, 129 amostras correspondentes aos afloramentos El Palomar, Chinchilla e El Vaquerito. Estes afloramentos situam-se em Cuba Central e caracterizam a Formação Mata da UTE Camajuaní. A análise bioestratigráfica permitiu identificar nos sedimentos Aptianos-Albianos desta formação 87 espécies agrupadas em 40 g