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91.
Harsh Sancheti Garnik Akopian Fei Yin Roberta D. Brinton John P. Walsh Enrique Cadenas 《PloS one》2013,8(7)
Alzheimer’s disease is a progressive neurodegenerative disease that entails impairments of memory, thinking and behavior and culminates into brain atrophy. Impaired glucose uptake (accumulating into energy deficits) and synaptic plasticity have been shown to be affected in the early stages of Alzheimer’s disease. This study examines the ability of lipoic acid to increase brain glucose uptake and lead to improvements in synaptic plasticity on a triple transgenic mouse model of Alzheimer’s disease (3xTg-AD) that shows progression of pathology as a function of age; two age groups: 6 months (young) and 12 months (old) were used in this study. 3xTg-AD mice fed 0.23% w/v lipoic acid in drinking water for 4 weeks showed an insulin mimetic effect that consisted of increased brain glucose uptake, activation of the insulin receptor substrate and of the PI3K/Akt signaling pathway. Lipoic acid supplementation led to important changes in synaptic function as shown by increased input/output (I/O) and long term potentiation (LTP) (measured by electrophysiology). Lipoic acid was more effective in stimulating an insulin-like effect and reversing the impaired synaptic plasticity in the old mice, wherein the impairment of insulin signaling and synaptic plasticity was more pronounced than those in young mice. 相似文献
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93.
Karen Einsfeldt Isis Cavalcante Baptista Juliana Christina Castanheira Vicente Pereira Roberta Eitler Bruno Fabiana Vieira Mello Isabele Campos Costa-Amaral Elaine Sobral da Costa Maria Cecília Menks Ribeiro Marcelo Gerardin Poirot Land Tito Lívio Moitinho Alves Ariane Leites Larentis Rodrigo Volcan Almeida 《PloS one》2016,11(9)
94.
Jailson F. Moura Esteban Acevedo-Trejos Davi C. Tavares Ana C. O. Meirelles Cristine P. N. Silva Larissa R. Oliveira Roberta A. Santos Janaína C. Wickert Rodrigo Machado Salvatore Siciliano Agostino Merico 《PloS one》2016,11(1)
The genus Kogia, which comprises only two extant species, Kogia sima and Kogia breviceps, represents one of the least known groups of cetaceans in the global ocean. In some coastal regions, however, stranding events of these species have been relatively common over the last decades. Stranding provides the opportunity to investigate the biology of these cetaceans and to explore the epidemiological aspects associated with the mortality of the organisms found on the beach. A number of disturbances (including pelagic fisheries, chemical pollution, boat strikes, and noise pollution) have been confirmed to pose a particular threat to the Kogia species. However, no study has yet investigated potential relationships between environmental conditions and stranding events. Here we analyse how a collection of environmental, physical, and biological variables, such as wind, sea surface temperature (SST), water depth, and chlorophyll-a, correlate to Kogia stranding events along the Brazilian coast. The results of our statistical analyses suggest that K. sima is more likely found in warm tropical waters, which provide an explanation for the high frequency of stranding in northeastern Brazilian coast. In contrast, K. breviceps appears to have a preference for temperate and productive waters. Wind speed results to be also an important factor for predicting Kogia strandings in Brazilian coast. Additionally, literature information in combination with our own data and analyses of stomach contents confirms that oceanic cephalopods constitute the primary nutritional source of both Kogia species. By using the available information as a qualitative proxy for habitat preference and feeding ecology, our study provides a novel and comprehensive assessment of Kogia stranding data in relation to environmental conditions along the Brazilian coast. 相似文献
95.
Contemporary patterns of genetic diversity of cedrela fissilis offer insight into the shaping of seasonal forests in eastern South America 下载免费PDF全文
96.
Roberta?SalmiEmail author Uzma?Rahman Diane?M.?Doran-Sheehy 《International journal of primatology》2016,37(2):200-212
Although the level of handedness in humans varies cross-culturally, humans are generally described as right-handed, which has been considered a uniquely human trait. Recently, captive chimpanzees (Pan troglodytes) have been shown to exhibit right-hand preference when performing bimanual but not unimanual tasks. Less clear is whether this pattern also occurs in wild chimpanzees and other African apes. Using videos (N = 49) of six wild western gorillas (Gorilla gorilla gorilla) feeding on termites at the Mondika Research Center (Republic of Congo), we tested whether they exhibit hand preference when performing unimanual, i.e., reaching for termite mound pieces; bimanual, i.e., “termite tapping”: rhythmically shaking a piece of termite mound with the dominant hand and collecting the termites in the other hand tasks; or hand transfer prior to bimanual tasks, i.e., transferring a piece of termite mound from one hand to the other. All individuals exhibited exclusive hand preference when performing the bimanual tasks, with five of six gorillas preferring the right hand. Conversely, most individuals did not show any manual preference during the unimanual task. In addition, hand preference during hand transfer revealed clear hand dominance of similar strength and direction of those shown for the bimanual task, suggesting that this measure is as sensitive as the bimanual task itself. Thus, we propose “termite feeding” as a novel task to be considered in future hand-preference studies in wild western gorillas. Our results are in concordance with those for chimpanzees and captive gorillas showing hemispheric specialization for bimanual actions in apes. 相似文献
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98.
Marcello Locatelli Roberta Cifelli Giuseppe Carlucci Annalisa Romagnoli 《Journal of enzyme inhibition and medicinal chemistry》2016,31(1):106-111
A new and specific HPLC–DAD method for the direct determination of Prulifloxacin and its active metabolite, Ulifloxacin, in human plasma has been developed. Plasma samples were analysed after a simple solid phase extraction (SPE) clean-up using a new HILIC stationary phase based high-performance liquid chromatography (HPLC) column and an ammonium acetate buffer (5?mM, pH 5.8)/acetonitrile (both with 1% Et3N, v/v) mobile phase in isocratic elution mode, with Danofloxacin as the internal standard. Detection was performed using DAD from 200 to 500?nm and quantitative analyses were carried out at 278?nm. The LOQ of the method was 1?μg/mL of the cited analytes and the calibration curve showed a good linearity up to 25?μg/mL. For both analytes the precision (RSD%) and the trueness (bias%) of the method fulfil with International Guidelines. The method was applied for stability studies, at three QC concentration levels, in human plasma samples stored at different temperature of?+?25,?+?4 and ?20?°C in order to evaluate plasma stability profiles. 相似文献
99.
Alessandra Gismondi Laura Bruno Simonetta Antonaroli Roberta Congestri 《International journal of phytoremediation》2016,18(9):869-876
In the present study a closed incubator, designed for biofilm growth on artificial substrata, was used to grow three isolates of biofilm-forming heterocytous cyanobacteria using an artificial wastewater secondary effluent as the culture medium. We evaluated biofilm efficiency in removing phosphorus, by simulating biofilm-based tertiary wastewater treatment and coupled this process with biodiesel production from the developed biomass. The three strains were able to grow in the synthetic medium and remove phosphorus in percentages, between 6 and 43%, which varied between strains and also among each strain according to the biofilm growth phase. Calothrix sp. biofilm turned out to be a good candidate for tertiary treatment, showing phosphorus reducing capacity (during the exponential biofilm growth) at the regulatory level for the treated effluent water being discharged into natural water systems.Besides phosphorus removal, the three cyanobacterial biofilms produced high quality lipids, whose profile showed promising chemical stability and combustion behavior. Further integration of the proposed processes could include the integration of oil extracted from these cyanobacterial biofilms with microalgal oil known for high monounsaturated fatty acids content, in order to enhance biodiesel cold flow characteristics. 相似文献
100.
Gavino Faa Mirko Manchia Roberta Pintus Clara Gerosa Maria Antonietta Marcialis Vassilios Fanos 《Birth defects research. Part C, Embryo today : reviews》2016,108(3):207-223
Starting from the Developmental Origins of Health and Disease (DOHaD) hypotheses proposed by David Barker, namely fetal programming, in the past years, there is a growing evidence of the major role played by epigenetic factors during the intrauterine life and the perinatal period. Furthermore, it has been assessed that these factors can affect the health status in infancy and even in adulthood. In this review, we focus our attention on the fetal programming of the brain, analyzing the most recent literature concerning the epigenetic factors that can influence the development of neuropsychiatric disorders such as bipolar disorders, major depressive disorders, and schizophrenia. The perinatal epigenetic factors have been divided in two main groups: maternal factors and fetal factors. The maternal factors include diet, smoking, alcoholism, hypertension, malnutrition, trace elements, stress, diabetes, substance abuse, and exposure to environmental toxicants, while the fetal factors include hypoxia/asphyxia, placental insufficiency, prematurity, low birth weight, drugs administered to the mother or to the baby, and all factors causing intrauterine growth restriction. A better comprehension of the possible mechanisms underlying the pathogenesis of these diseases may help researchers and clinicians develop new diagnostic tools and treatments to offer these patients a tailored medical treatment strategy to improve their quality of life. Birth Defects Research (Part C) 108:207–223, 2016. © 2016 Wiley Periodicals, Inc. 相似文献