708 research outputs found
Potential geographic distribution of Hantavirus reservoirs in Brazil
Hantavirus cardiopulmonary syndrome is an emerging zoonosis in Brazil. Human infections occur via inhalation of aerosolized viral particles from excreta of infected wild rodents. Necromys lasiurus and Oligoryzomys nigripes appear to be the main reservoirs of hantavirus in the Atlantic Forest and Cerrado biomes. We estimated and compared ecological niches of the two rodent species, and analyzed environmental factors influencing their occurrence, to understand the geography of hantavirus transmission. N. lasiurus showed a wide potential distribution in Brazil, in the Cerrado, Caatinga, and Atlantic Forest biomes. Highest climate suitability for O. nigripes was observed along the Brazilian Atlantic coast. Maximum temperature in the warmest months and annual precipitation were the variables that most influence the distributions of N. lasiurus and O. nigripes, respectively. Models based on occurrences of infected rodents estimated a broader area of risk for hantavirus transmission in southeastern and southern Brazil, coinciding with the distribution of human cases of hantavirus cardiopulmonary syndrome. We found no demonstrable environmental differences among occurrence sites for the rodents and for human cases of hantavirus. However, areas of northern and northeastern Brazil are also apparently suitable for the two species, without broad coincidence with human cases. Modeling of niches and distributions of rodent reservoirs indicates potential for transmission of hantavirus across virtually all of Brazil outside the Amazon Basin
Severe stress switches CRF action in the nucleus accumbens from appetitive to aversive.
Stressors motivate an array of adaptive responses ranging from \u27fight or flight\u27 to an internal urgency signal facilitating long-term goals. However, traumatic or chronic uncontrollable stress promotes the onset of major depressive disorder, in which acute stressors lose their motivational properties and are perceived as insurmountable impediments. Consequently, stress-induced depression is a debilitating human condition characterized by an affective shift from engagement of the environment to withdrawal. An emerging neurobiological substrate of depression and associated pathology is the nucleus accumbens, a region with the capacity to mediate a diverse range of stress responses by interfacing limbic, cognitive and motor circuitry. Here we report that corticotropin-releasing factor (CRF), a neuropeptide released in response to acute stressors and other arousing environmental stimuli, acts in the nucleus accumbens of naive mice to increase dopamine release through coactivation of the receptors CRFR1 and CRFR2. Remarkably, severe-stress exposure completely abolished this effect without recovery for at least 90 days. This loss of CRF\u27s capacity to regulate dopamine release in the nucleus accumbens is accompanied by a switch in the reaction to CRF from appetitive to aversive, indicating a diametric change in the emotional response to acute stressors. Thus, the current findings offer a biological substrate for the switch in affect which is central to stress-induced depressive disorders
Guidelines of the Brazilian Association of Studies on Alcohol and Other Drugs (ABEAD) for diagnoses and treatment of psychiatric comorbidity with alcohol and other drugs dependence
Recently, several studies have focused on comorbity psychiatric disorders with alcohol and other substance dependence. The Brazilian Association of Studies on Alcohol and Other Drugs proposed the Brazilian Guidelines project. This study review diagnostic and therapeutic criteria to the most prevalent psychiatric comorbidities. Randomized clinical trials, epidemiological, animal studies and other forms of research are reviewed. The main psychiatric comorbidities are studied based on guidelines adopted by other countries and the literature data resumed. Epidemiological aspects, diagnoses, integrated treatment and service organization, as well as specific psychotherapic and pharmacological treatment are discussed. The Brazilian Association of Studies on Alcohol and Other Drugs Guidelines reassures the importance of adequate diagnoses and treatment regarding alcoholic and drug dependent patients suffering of comorbid psychiatric disorders.O diagnóstico e tratamento de comorbidade psiquiátrica e dependência de álcool e outras substâncias tem sido objeto de inúmeros estudos nos últimos anos. A Associação Brasileira de Estudos do Álcool e Outras Drogas desenvolveu o projeto Diretrizes. Este trabalho visa o desenvolvimento de critérios diagnósticos e terapêuticos atualizados para as comorbidades psiquiátricas mais prevalentes. Ensaios clínicos randomizados, estudos epidemiológicos, com animais e outros estudos são revisados. As principais comorbidades psiquiátricas são estudadas e os dados de literatura resumidos, tendo como referência diretrizes adotadas em outros países. São abordados aspectos epidemiológicos, critérios diagnósticos, tratamento integrado e organização de serviço especializado, assim como especificidades do tratamento psicoterápico e farmacológico. As Diretrizes da Associação Brasileira de Estudos do Álcool e Outras Drogas reforçam a importância da abordagem adequada do dependente químico portador de comorbidade psiquiátrica.Universidade Federal de Santa Catarina Núcleo de PsiquiatriaInstituto de Psiquiatria de Santa CatarinaUniversidade Federal de São Paulo (UNIFESP) Unidade de Pesquisa em Álcool e DrogasSanta Casa de Misericórdia de São Paulo Unidade de Álcool e DrogasUniversidade de São Paulo Faculdade de Medicina Hospital das ClinicasCentro de Atendimento Médico e SocialHospital de Clínicas de Porto AlegreHospital Israelita Albert EinsteinSanta Casa do Rio de Janeiro Setor de Dependência QuímicaUniversidade Gama FilhoUNIFESP, Unidade de Pesquisa em Álcool e DrogasSciEL
Nothing Lasts Forever: Environmental Discourses on the Collapse of Past Societies
The study of the collapse of past societies raises many questions for the theory and practice of archaeology. Interest in collapse extends as well into the natural sciences and environmental and sustainability policy. Despite a range of approaches to collapse, the predominant paradigm is environmental collapse, which I argue obscures recognition of the dynamic role of social processes that lie at the heart of human communities. These environmental discourses, together with confusion over terminology and the concepts of collapse, have created widespread aporia about collapse and resulted in the creation of mixed messages about complex historical and social processes
Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine
[This corrects the article DOI: 10.1186/s13054-016-1208-6.]
Hypercalcemia in a patient with disseminated paracoccidioidomycosis: a case report
<p>Abstract</p> <p>Introduction</p> <p>Hypercalcemia is well described in various granulomatous disorders, such as sarcoidosis, tuberculosis, berylliosis, leprosy and fungal infections. However, the association of <it>Paracoccidioides brasiliensis </it>and hypercalcemia is rare: to the best of our knowledge, only two cases have previously been reported, and neither had a clear documentation of the etiology of the hypercalcemia.</p> <p>Case presentation</p> <p>We report the case of a 22-year-old man in whom disseminated infection with paracoccidioidomycosis was associated with hypercalcemia. The patient had a high normal serum level of 1,25-dihydroxyvitamin D and a suppressed parathyroid hormone value, an indication that the hypercalcemia was not mediated by parathyroid hormone and might be associated with 1,25-dihydroxyvitamin D.</p> <p>Conclusion</p> <p>The episode resolved readily with administration of corticosteroids, an outcome suggesting that this is an effective treatment of hypercalcemia of this origin. On follow-up, while receiving antifungal therapy for <it>P. brasiliensis </it>the patient's calcium values remained normal.</p
Numerical modeling of the tension stiffening in reinforced concrete members via discontinuum models
[prova tipográfica]This study presents a numerical investigation on the fracture mechanism of tension stiffening phenomenon in reinforced concrete members. A novel approach using the discrete element method (DEM) is proposed, where three-dimensional randomly generated distinct polyhedral blocks are used, representing concrete and one-dimensional truss elements are utilized, representing steel reinforcements. Thus, an explicit representation of reinforced concrete members is achieved, and the mechanical behavior of the system is solved by integrating the equations of motion for each block using the central difference algorithm. The inter-block interactions are taken into consideration at each contact point with springs and cohesive frictional elements. Once the applied modeling strategy is validated, based on previously published experimental findings, a sensitivity analysis is performed for bond stiffness, cohesion strength, and the number of truss elements. Hence, valuable inferences are made regarding discontinuum analysis of reinforced concrete members, including concrete-steel interaction and their macro behavior. The results demonstrate that the proposed phenomenological modeling strategy successfully captures the concrete-steel interaction and provides an accurate estimation of the macro behavior
Alteration of the serum levels of the epidermal growth factor receptor and its ligands in patients with non-small cell lung cancer and head and neck carcinoma
Serum levels of the soluble epidermal growth factor receptor (sEGFR) and its ligands epidermal growth factor (EGF), transforming growth factor-α (TGF-α) and amphiregulin (AR) were measured in healthy donors and patients with non-small cell lung cancer (NSCLC) and head and neck carcinoma (HNC). In NSCLC, we found sEGFR and EGF levels significantly lowered in patients with respect to healthy donors. In HNC patients, significantly diminished levels were found in the case of sEGFR, EGF and also AR. In both malignancies, no significant association was found between the serum levels of the molecules and the patients' gender, age or smoking habit. Only a significant association was found between the decrease of sEGFR and the absence of distant metastasis in NSCLC and the tumour stage in HNC. The most interesting result was that combining sEGFR and EGF, sensitivities of 88% in NSCLC and 100% in HNC were reached without losing specificity (97.8% in both cases). The use of discriminant analysis and logistic regression improved the sensitivity for NSCLC and the specificity for HNC. These data demonstrate a potentially interesting value of the serum levels of sEGFR and EGF, especially when combined, as markers for NSCLC and HNC
Capillaria hepatica-induced septal fibrosis in rats: a contribution to the study of liver fibrogenesis
INTRODUCTION: Septal fibrosis of the liver regularly develops in rats infected with the nematode Capillaria hepatica. Curative treatment of the infection prevents the development of septal fibrosis when intervention occurs up to postinfection day (PID) 15, but not later. The present investigation aimed to demonstrate which parasitic factors are present when the process of septal fibrosis can no longer be prevented by curative treatment. METHODS: Wistar rats were infected with 600 embryonated eggs of C. hepatica administered by gavage and treated with ivermectin and mebendazole in separate groups at PIDs 10, 12, 15, 17 or 20. Rats from each group and their nontreated controls, were killed and examined 40 days after the end of treatment. RESULTS: Findings by PID 15 were compatible with the stage of complete maturation of infection, when worms and eggs were fully developed and a complex host-parasite multifocal necroinflammatory reaction showed greater intensity, but with no signs of septal fibrosis, which appeared from PID 17 onward. CONCLUSIONS: Since the worms spontaneously died by PID 15, not only septal fibrosis production, but also its maintenance and further development appeared dependent on the presence of eggs, which were the only parasitic factor remaining thereafter.INTRODUÇÃO: A fibrose septal do fígado se desenvolve regularmente em ratos infectados pelo nematódeo Capillaria hepatica. O tratamento curativo da infecção, feito antes do 15º dia da infecção, mas não mais tarde, impediu o aparecimento da fibrose septal. O presente trabalho procura verificar qual o estado do parasitismo aos 15 dias da infecção, crucial para patogenia da fibrose septal. MÉTODOS: Ratos foram infectados por via digestiva com 600 ovos embrionados de C. hepatica e tratados com Ivermectina e mebendazol, em grupos separados, aos 10, 12, 15, 17 ou 20 dias após a infecção. O animal de cada grupo e seus respectivos controles foram mortos e examinados aos 40 dias após o fim do tratamento. RESULTADOS: Os achados aos 15 dias da infecção mostraram a maturação completa da parasitose, com presença de ovos e vermes, circundados por reação necro-inflamatória, mas ainda sem fibrose septal. Daí por diante, a fibrose septal se fez presente. CONCLUSÕES: Como os vermes morrem espontaneamente após o 15º dia da infecção, não apenas a origem, mas o posterior crescimento e a manutenção da fibrose septal dependem da presença dos ovos acumulados no fígado, os quais são os únicos elementos parasitários presentes após o 15º dia da infecção por C. hepatica no rato
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