130 research outputs found

    Pathological Findings in the Adrenal Glands of 80 Dogs

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    Background: The adrenal glands development important endocrine functions and can be affected by primary or secondary diseases. These adrenal gland pathologies may induce clinical syndromes resulting from abnormalities in the production and secretion of hormones. Data about pathological changes in dogs are scarce. Therefore, the aim of the present study was to identify and evaluate the histopathological and epidemiological features of adrenal changes in dogs submitted to necropsy examination from 2005 to 2016 in a Veterinary Teaching Hospital, Londrina, ParanĂĄ, Brazil.Material, Methods & Results: During this period, 80 animals presented alterations of adrenal gland, representing 5.5% of all necropsied dogs. The pure breed dogs representing 58.6% and mixed breed 41.4%; 53.4% were female and 46.6% were male. The non-neoplastic adrenal lesions were more frequently (57.5%) compared to the neoplastic changes (42.5%). Most of the adrenal glands lesions occurred in older dogs (60%), following by the middle aged (31.25%) and young dogs (8.75%). The main non-neoplastic lesions observed in the adrenal glands were of hyperplastic (69.5%) and circulatory (26%) origin, among the earlier, 68.8% were diffuse hyperplasia and 31.2% nodular hyperplasia. The nodular hyperplasia was classified as micronodular multifocal in 40% of the glands with nodular hyperplasia, macronodular multifocal in 30%, micronodular diffuse in 20%, and micronodular focal in 10%. The neoplasms observed were adrenocortical adenoma (ACA) in 44.1%, pheochromocytomas in 23.5% and adrenocortical carcinomas (ACC) in 11.7% of the dogs with adrenal tumors. Metastasis from other primary tumors were observed in 20.6%.Discussion: The data in veterinary literature about the frequency of changes in adrenal gland of dogs are scarce and focus features of diagnosis by ultrasound examination. Most of the adrenal changes observed in the present study were incidental findings observed during the necropsy examination and no specific clinical signs were observed. Non-neoplastic adrenal lesions, mainly of hyperplastic origin, were more frequently observed compared to the neoplastic changes. Differing from previous studies, the diffuse hyperplasia was the most common non neoplastic finding in the adrenal glands. Considering the subclassification of nodular hyperplasia, the multifocal micronodular and macronodular multifocal pattern were the most frequent. In veterinary literature, there are no data about frequency of nodular hyperplastic subtypes. However, in humans the subclassification of nodular hyperplasia is associated to development of endocrine disorders. Previous studies reported lower incidence of neoplastic changes in adrenal gland of dogs compared to the present results. The adrenocortical adenoma was the most common primary tumor, followed by the adrenocortical carcinoma, pheochromocytoma and adrenocortical carcinoma. Congestion and hemorrhage were common findings observed in the adrenal gland primary tumors. On the other hand, necrosis and inflammatory infiltrate were observed only in the adrenocortical carcinomas. These histopathological features may be used as tool in the differential diagnosis between well differentiated adrenocortical carcinoma and adenoma. The histopathological examination was fundamental to differential and definitive diagnosis of all canine adrenal gland disorders observed

    SEROLOGICAL DETECTION OF HEPATITIS A VIRUS IN FREE-RANGING NEOTROPICAL PRIMATES (Sapajus spp., Alouatta caraya) FROM THE PARANÁ RIVER BASIN, BRAZIL

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    Nonhuman primates are considered as the natural hosts of Hepatitis A virus (HAV), as well as other pathogens, and can serve as natural sentinels to investigate epizootics and endemic diseases that are of public health importance. During this study, blood samples were collected from 112 Neotropical primates (NTPs) (Sapajus nigritus and S. cay, n = 75; Alouatta caraya, n = 37) trap-captured at the ParanĂĄ River basin, Brazil, located between the States of ParanĂĄ and Mato Grosso do Sul. Anti-HAV IgG antibodies were detected in 4.5% (5/112) of NTPs, specifically in 6.7% (5/75) of Sapajus spp. and 0% (0/37) of A. caraya. In addition, all samples were negative for the presence of IgM anti-HAV antibodies. These results suggest that free-ranging NTPs were exposed to HAV within the geographical regions evaluated

    A New Minimal-Stress Freely-Moving Rat Model for Preclinical Studies on Intranasal Administration of CNS Drugs

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    Purpose. To develop a new minimal-stress model for intranasal administration in freely moving rats and to evaluate in this model the brain distribution of acetaminophen following intranasal versus intravenous administration. Methods. Male Wistar rats received one intranasal cannula, an intra-cerebral microdialysis probe, and two blood cannulas for drug administration and serial blood sampling respectively. To evaluate this novel model, the following experiments were conducted. 1) Evans Blue was administered to verify the selectivity of intranasal exposure. 2) During a 1 min infusion 10, 20, or 40 Όl saline was administered intranasally or 250 ”l intravenously. Corticosterone plasma concentrations over time were compared as biomarkers for stress. 3) 200 ”g of the model drug acetaminophen was given in identical setup and plasma, and brain pharmacokinetics were determined. Results. In 96 % of the rats, only the targeted nasal cavity was deeply colored. Corticosterone plasma concentrations were not influenced, neither by route nor volume of administration. Pharmacokinetics of acetaminophen were identical after intravenous and intranasal administration, although the Cmax in microdialysates was reached a little earlier following intravenous administration. Conclusion. A new minimal-stress model for intranasal administration in freely moving rats has been successfully developed and allows direct comparison with intravenous administration. KEY WORDS: acetaminophen; brain; intranasal infusion; microdialysis; pharmacokinetics

    SEROLOGICAL DETECTION OF HEPATITIS A VIRUS IN FREE-RANGING NEOTROPICAL PRIMATES (Sapajus spp., Alouatta caraya) FROM THE PARANÁ RIVER BASIN, BRAZIL

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    Nonhuman primates are considered as the natural hosts of Hepatitis A virus (HAV), as well as other pathogens, and can serve as natural sentinels to investigate epizootics and endemic diseases that are of public health importance. During this study, blood samples were collected from 112 Neotropical primates (NTPs) (Sapajus nigritus and S. cay, n = 75; Alouatta caraya, n = 37) trap-captured at the ParanĂĄ River basin, Brazil, located between the States of ParanĂĄ and Mato Grosso do Sul. Anti-HAV IgG antibodies were detected in 4.5% (5/112) of NTPs, specifically in 6.7% (5/75) of Sapajus spp. and 0% (0/37) of A. caraya. In addition, all samples were negative for the presence of IgM anti-HAV antibodies. These results suggest that free-ranging NTPs were exposed to HAV within the geographical regions evaluated

    Online collaboration and cooperation : the recurring importance of evidence, rationale and viability

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    This paper investigates collaboration in teaching and learning and draws out implications for the promotion of collaboration within online environments. It is divided into four sections. First the case for collaboration, including specifically cooperative approaches, is explored. This case revolves around the impact of collaboration on the quality of learning and on learning outcomes. Collaboration is seen as constrained by context but, if structured and rewarded, it will bring important motivational and cognitive benefits. Next, the case for online collaboration is examined. This is based on longstanding arguments about the benefits of working together albeit in an environment which offers greater reach; a mix of media; and archives of interaction. The third section of the paper compares perspectives on online collaboration with a longer tradition of research into collaboration in general; it critiques the idea that online mediation offers a paradigm change in teaching and learning. The fourth section of the paper considers future directions for promoting online collaboration

    Tuberculosis and HIV Co-Infection

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    Tuberculosis (TB) and HIV co-infections place an immense burden on health care systems and pose particular diagnostic and therapeutic challenges. Infection with HIV is the most powerful known risk factor predisposing for Mycobacterium tuberculosis infection and progression to active disease, which increases the risk of latent TB reactivation 20-fold. TB is also the most common cause of AIDS-related death. Thus, M. tuberculosis and HIV act in synergy, accelerating the decline of immunological functions and leading to subsequent death if untreated. The mechanisms behind the breakdown of the immune defense of the co-infected individual are not well known. The aim of this review is to highlight immunological events that may accelerate the development of one of the two diseases in the presence of the co-infecting organism. We also review possible animal models for studies of the interaction of the two pathogens, and describe gaps in knowledge and needs for future studies to develop preventive measures against the two diseases

    Factors influencing terrestriality in primates of the Americas and Madagascar

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    Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (bodymass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use

    Rethinking the fall of the planter class

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    This issue of Atlantic Studies began life as a one-day conference held at Chawton House Library in Hampshire, UK, and funded by the University of Southampton. The conference aimed, like this issue, to bring together scholars currently working on the history of the British West Indian planter class in the eighteenth and nineteenth centuries and to discuss how, when, and why the fortunes of the planters went into decline. As this introduction notes, the difficulties faced by the planter class in the British West Indies from the 1780s onwards were an early episode in a wider drama of decline for New World plantation economies. The American historian Lowell Ragatz published the first detailed historical account of their fall. His work helped to inform the influential arguments of Eric Williams, which were later challenged by Seymour Drescher. Recent research has begun to offer fresh perspectives on the debate about the decline of the planters, and this collection brings together articles taking a variety of new approaches to the topic, encompassing economic, political, cultural, and social histor

    Factors influencing terrestriality in primates of the Americas and Madagascar

    Get PDF
    Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (body mass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use
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