Latitudinal Variation in Seasonal Activity and Mortality in Ratsnakes (Elaphe obsoleta)

The ecology of ectotherms should be particularly affected by latitude because so much of their biology is temperature dependent. Current latitudinal patterns should also be informative about how ectotherms will have to modify their behavior in response to climate change. We used data from a total of 175 adult black ratsnakes (Elaphe obsoleta) radio tracked in Ontario, Illinois, and Texas, a latitudinal distance of \u3e 1500 km, to test predictions about how seasonal patterns of activity and mortality should vary with latitude. Despite pronounced differences in temperatures among study locations, and despite ratsnakes in Texas not hibernating and switching from diurnal to nocturnal activity in the summer, seasonal patterns of snake activity were remarkably similar during the months that snakes in all populations were active. Rather than being a function of temperature, activity may be driven by the timing of reproduction, which appears similar among populations. Contrary to the prediction that mortality should be highest in the most active population, overall mortality did not follow a clinal pattern. Winter mortality did increase with latitude, however, consistent with temperature limiting the northern distribution of ratsnakes. This result was opposite that found in the only previous study of latitudinal variation in winter mortality in reptiles, which may be a consequence of whether or not the animals exhibit true hibernation. Collectively, these results suggest that, at least in the northern part of their range, ratsnakes should be able to adjust easily to, and may benefit from, a warmer climate, although climate-based changes to the snakes\u27 prey or habitat, for example, could alter that prediction

Exploring metabolic responses of potato tissue induced by electric pulses

In this study, we investigated the metabolic responses of potato tissue induced by pulsed electric field (PEF). Potato tissue was subjected to field strengths ranging from 30 to 500 V/cm, with a single rectangular pulse of 10 μs, 100 μs, or 1 ms. Metabolic responses were monitored using isothermal calorimetry, changes on electrical resistance during the delivery of the pulse, as well as impedance measurements. Our results show that the metabolic response involves oxygen consuming pathways as well as other unidentified events that are shown to be insensitive to metabolic inhibitors such as KCN and sodium azide. The metabolic response is strongly dependent on pulsing conditions and is independent of the total permeabilization achieved by the pulse. Evidence shows that calorimetry is a simple and powerful method for exploring conditions for metabolic stimulation, providing information on metabolic responses that can not be obtained from electrical measurements. This study set the basis for further investigations on defense-related consequences of PEF-induced stress.Sparbanksstiftelsen Färs & Frosta (Sweden).Fundação para a Ciência e a Tecnologia (FCT).Lund University (Sweden).Department of Cell and Organism Biology; Department of Plant Biochemistry

RANTES/CCL5 and Risk for Coronary Events: Results from the MONICA/KORA Augsburg Case-Cohort, Athero-Express and CARDIoGRAM Studies

BACKGROUND: The chemokine RANTES (regulated on activation, normal T-cell expressed and secreted)/CCL5 is involved in the pathogenesis of cardiovascular disease in mice, whereas less is known in humans. We hypothesised that its relevance for atherosclerosis should be reflected by associations between CCL5 gene variants, RANTES serum concentrations and protein levels in atherosclerotic plaques and risk for coronary events. METHODS AND FINDINGS: We conducted a case-cohort study within the population-based MONICA/KORA Augsburg studies. Baseline RANTES serum levels were measured in 363 individuals with incident coronary events and 1,908 non-cases (mean follow-up: 10.2±4.8 years). Cox proportional hazard models adjusting for age, sex, body mass index, metabolic factors and lifestyle factors revealed no significant association between RANTES and incident coronary events (HR [95% CI] for increasing RANTES tertiles 1.0, 1.03 [0.75-1.42] and 1.11 [0.81-1.54]). None of six CCL5 single nucleotide polymorphisms and no common haplotype showed significant associations with coronary events. Also in the CARDIoGRAM study (>22,000 cases, >60,000 controls), none of these CCL5 SNPs was significantly associated with coronary artery disease. In the prospective Athero-Express biobank study, RANTES plaque levels were measured in 606 atherosclerotic lesions from patients who underwent carotid endarterectomy. RANTES content in atherosclerotic plaques was positively associated with macrophage infiltration and inversely associated with plaque calcification. However, there was no significant association between RANTES content in plaques and risk for coronary events (mean follow-up 2.8±0.8 years). CONCLUSIONS: High RANTES plaque levels were associated with an unstable plaque phenotype. However, the absence of associations between (i) RANTES serum levels, (ii) CCL5 genotypes and (iii) RANTES content in carotid plaques and either coronary artery disease or incident coronary events in our cohorts suggests that RANTES may not be a novel coronary risk biomarker. However, the potential relevance of RANTES levels in platelet-poor plasma needs to be investigated in further studies

Detecção de anticorpos anti-Neospora caninum em amostras individuais e coletivas de leite de bovinos pela reação de imunofluorescência indireta

Neospora caninum é um agente envolvido em perdas reprodutivas em bovinos. O diagnóstico dessa infecção é de grande importância, principalmente para programas de erradicação e controle. Sendo assim, os objetivos deste estudo foram: (1) adaptar uma reação de imunofluorescência indireta (RIFI) para detecção de anticorpos anti-N. caninum no leite, a partir de uma RIFI padronizada para a detecção desses anticorpos no soro sanguíneo, (2) analisar a concordância entre a detecção desses anticorpos pela RIFI no soro sanguíneo e no leite de fêmeas bovinas, (3) avaliar a viabilidade da RIFI para a detecção de anticorpos anti-N. caninum em amostras coletivas de leite. Foram testadas amostras de soro sanguíneo e de leite, coletadas de 112 vacas em lactação, e seis amostras coletivas de leite, correspondentes a cada uma das propriedades avaliadas. Encontrou-se 78% de concordância entre a detecção de anticorpos no soro sanguíneo (com título de anticorpos >50) e no leite, com sensibilidade de 90% e especificidade de 100% para a RIFI nas amostras de leite. Entretanto, para as vacas com títulos de anticorpos >100 no soro sanguíneo, tanto a concordância como os valores de sensibilidade e especificidade da RIFI no leite foram de 100%. Todas as amostras coletivas de leite foram positivas na RIFI. Isso demonstra que, conforme a propriedade pode-se eleger com segurança qual a melhor abordagem diagnóstica a ser adotada em relação à coleta de soro sanguíneo ou de leite para a pesquisa de N. caninum pela RIFI. Além disso, a determinação da presença de anticorpos em amostras coletivas de leite pode servir para diagnóstico e triagem de rebanhos com animais infectados

RANTES/CCL5 and risk for coronary events: Results from the MONICA/KORA Augsburg case-cohort, Athero-express and CARDIoGRAM studies

Background: The chemokine RANTES (regulated on activation, normal T-cell expressed and secreted)/CCL5 is involved in the pathogenesis of cardiovascular disease in mice, whereas less is known in humans. We hypothesised that its relevance for atherosclerosis should be reflected by associations between CCL5 gene variants, RANTES serum concentrations and protein levels in atherosclerotic plaques and risk for coronary events. Methods and Findings: We conducted a case-cohort study within the population-based MONICA/KORA Augsburg studies. Baseline RANTES serum levels were measured in 363 individuals with incident coronary events and 1,908 non-cases (mean follow-up: 10.2±

Utilização de biópsias da terceira pálpebra e mucosa retal em ovinos para diagnóstico de scrapie em uma propriedade da região sul do Brasil

Scrapie é uma encefalopatia espongiforme transmissível (EET) que causa lesões cerebrais degenerativas em ovinos e caprinos. Caracteriza-se pelo acúmulo, no tecido encefálico e linforreticular, da forma anormal da proteína priônica (PrP Sc) que provoca a morte maciça de neurônios e células gliais, além de vacuolização intensa no tecido afetado. Esse trabalho descreve a utilização da técnica de imuno-histoquímica (IHQ) para proteína priônica em tecido linforreticular de biópsias de terceira pálpebra e mucosa retal, como método diagnóstico de scrapie em ovinos. Realizaram-se exames de IHQ para scrapie em amostras de uma propriedade de origem de um ovino com diagnóstico dessa enfermidade. Utilizaram-se anticorpos monoclonais antipríon para diagnóstico ante mortem pela técnica de IHQ. Nas 318 amostras de biópsias analisadas, encontrou-se 19 resultados positivos para PrP Sc nos folículos de terceira pálpebra e não foi obtida marcação no tecido linfático de mucosa retal em nenhuma das amostras coletadas. Realizaram-se 18 necropsias dos animais positivos anteriormente por biópsia e 21 necropsias de ovinos parentes dos positivos de scrapie. Confirmou-se o resultado de scrapie pela IHQ após a necropsia dos animais positivos nas biópsias de terceira pálpebra. Nesses animais, os órgãos com maior número de cortes positivos foram a terceira pálpebra (18/18) e a tonsila (8/18). Nos ovinos com parentesco com os positivos, nenhum resultado de scrapie ocorreu. A utilização de tecidos linfoides no diagnóstico de scrapie por IHQ através de biópsias mostrou-se um método viável e eficaz para o diagnóstico pré-clínico