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181.
182.
Marta Érica Saidel Karen C. dos Santos Luís F.P. Nagano Carlos Alberto Montanari Andrei Leitão 《Bioorganic & medicinal chemistry letters》2017,27(17):4001-4006
Phenotypic assays were performed in prostate cancer cell lines to describe the biological activity of PI3K-AKT-mTOR pathway inhibitors retrieved from the virtual screening initiative. These novel chemicals share in common the aminopyridine scaffold, hitting PC-3 cells in macromolar range, with selectivity index over fibroblast cell lines. Moreover, a preliminary study of the mode of action by flow cytometry assay pointed out that these compounds had a rapamycin-like response for the PI3K-AKT-mTOR pathway modulation. 相似文献
183.
BIANCA ETHEL GUTIÉRREZ-AMAVIZCA ANDREAS GAL ROCÍO ORTÍZ-OROZCO ULRICH ORTH ERNESTO PRADO MONTES DE OCA JAIME PAUL GUTIÉRREZ-AMAVIZCA LUIS E. FIGUERA 《Journal of genetics》2017,96(1):161-164
Fabry disease (FD) is a lysosomal storage disorder, which develops due to a deficiency in the hydrolytic enzyme, α-galactosidase A (α-Gal A). Alpha-Gal A hydrolyzes glycosphingolipid globotriaosylceramide (Gb3), and an α-Gal A deficiency leads to Gb3 accumulation in tissues and cells in the body. This pathology is likely to involve multiple systems, but it is generally considered to affect primarily vascular endothelium. In this study, we investigated mutations in the GLA gene, which encodes α-Gal A, in Mexican families with FD. We included seven probands with FD that carried known mutations. We analysed pedigrees of the probands, and performed molecular screening in 65 relatives with the potential of carrying a GLA mutation. Five mutations (P40S, IVS4 +4, G328V, R363H, R404del) were detected in seven unrelated Mexican families with the classic FD phenotype. Of the 65 relatives examined, 42 (64.6%) had a GLA gene mutation. In summary, among seven Mexican probands with FD, 65 relatives were at risk of carrying a known GLA mutation, and molecular screening identified 42 individuals with the mutation. Thus, our findings showed that it is important to perform molecular analysis in families with FD to detect mutations and to provide accurate diagnoses for individuals that could be affected. 相似文献
184.
ELISA LOBATO SANTIAGO MERINO JUDITH MORALES GUSTAVO TOMÁS JOSUÉ MARTÍNEZ‐DE LA PUENTE ESTRELLA SÁNCHEZ SONIA GARCÍA‐FRAILE JUAN MORENO 《Ibis》2008,150(4):799-806
Sex differences in immune function are relatively well studied in vertebrate animals, although the patterns are not always clear in birds. The study of immune responses in nestlings of wild bird populations may constitute an appropriate way to investigate inherent intersexual differences while controlling for environmental conditions such as parasitism that affect male and female individuals growing in the same nest. We studied whether the cell‐mediated immune response, as measured by phytohaemagglutinin (PHA) injection, and the levels of circulating antibodies differ between sexes of Pied Flycatcher nestlings Ficedula hypoleuca. No sex differences in nestling cell‐mediated immune response were found, but females showed significantly higher levels of plasma immunoglobulins than males did. Although nestling birds may not have a fully functional humoral immune defence, our study indicates that sex differences in the humoral component exist at this early stage of life. Given the importance of antibodies in the fight against parasite, bacterial and viral infections, the intrinsic sex disparity in circulating antibodies may have important implications for the life history of each sex. 相似文献
185.
Lake Balaton (Hungary), one of the largest lakes in Europe, has undergone eutrophication and restoration during the last two decades. The first quantitative phytoplankton records date back to the 1930s, and since that time thousands of data have been published or accumulated in counting protocols or computer sheets. These data provide material for both scientific analyses (e.g. effects of global change) and applications (e.g. estimation of reference state for the Water Framework Directive). The ALMOBAL phytoplankton database was developed to provide computing support for these applications. It stores data in standardized forms, handles synonyms and allows analyses to be conducted on the basis of floral records, numbers or biomass. The analysis includes records of about 3000 phytoplankton samples taken during the past 60 years from two representative basins in Lake Balaton. This article represents the first attempt at historical reconstruction of the ecological status and compares it with changes in trophic state and current water quality. The results indicate that the phytoplankton biomass and community structure found in the early 1960s could be regarded as reference conditions. Statistical analyses support the view that late summer phytoplankton assemblages are the most sensitive indicators of trophic change, and clearly show the eutrophication of the lake that occurred from the mid-1970s to the mid-1990s and the restoration during the last decade. An additional advantage is that, since quality estimation is based on relative biomass, the method can be used to reconstruct water quality in cases when counting protocols are available, but some basic data for quantitative estimates are missing. 相似文献
186.
JAVIER BALBONTÍN JUAN JOSÉ NEGRO JOSÉ HERNÁN SARASOLA JUAN JOSÉ FERRERO DOMINGO RIVERA 《Ibis》2008,150(4):707-716
Occasional observations of Black‐shouldered Kites Elanus caeruleus in Europe date back to the mid‐19th century, but it was only recorded as a breeding species in the early 1960s in Portugal and a few years later in neighbouring Spain. This recent colonization, possibly from Africa where the species is abundant, may be due to climate change, land‐use changes in southern Europe, or both. As a first step to understanding this range expansion process we have developed a habitat selection model using data from the current strongholds of its European distribution. Comparing the proportion of different habitat types around 46 breeding sites and 45 randomly chosen plots, we have found that the area of cultivated parklands known as dehesas in Spain is a strong predictor of the current distribution range of breeding pairs of Black‐shouldered Kites. Specifically, the percentage of dehesas with planted cereal and a low density of trees (i.e. < 7 trees/ha and thus a savannah‐like habitat) within the study plots explained 44.6% of the residual deviance in our model. The minimal adequate model classified 81.3% of breeding sites and random plots correctly. Our results suggest that Black‐shouldered Kites may have taken advantage of the gradual increase of cultivated dehesas in the second half of the 20th century to expand its range in Europe. This particular type of dehesa is structurally similar to the African savannahs where the species thrives and may offer a higher density of rodents than traditional dehesas, which primarily contain pastureland for livestock ranching. 相似文献
187.
Franck Zenasni Todd Lubart Farzaneh Pahlavan StÉphane Jacob Anne-Yvonne Jacquet Christelle Lemoine 《PSN》2003,1(4):19-27
Studies on personality traits conducted during the past decade indicate that there is a set of emotion-related traits on which individuals differ. Moreover, other studies showed that there are some abilities related to the processing of both emotions and emotional information, referred to as the concept of emotional intelligence. The authors of the article evaluated one hundred adults (ranging in age from 20–50) using the French version of a series of scales to measure stable emotionrelated traits and emotional intelligence. The results showed that these instruments provide accurate internal consistency and reliability, and that there are significant relationships between the individual emotional characteristics observed. A factorial analysis conducted with varimax rotation underlined five primary factors identified as: Clear-sightedness of emotions, Emotional richness, Identification, Understanding and Emotional control. The average emotional profiles based on these five primary factors depend on gender and age. In particular, the female and the oldest participants showed a greater emotional richness. The examination of these five factors should lead to a better understanding of the relationships which exist between these emotional characteristics and cognitive performances, and their involvement in clinical syndromes. 相似文献
188.
Lörinczi E Napp J Contreras-Jurado C Pardo LA Stühmer W 《European biophysics journal : EBJ》2009,38(3):279-284
The ether-à-go-go potassium channels hEag1 and hEag2 are highly homologous. Even though both possess identical voltage-sensing
domain S4, the channels act differently in response to voltage. Therefore we asked whether transmembrane domains other than
the voltage sensor could contribute to the voltage-dependent behaviour of these potassium channels. For this chimaeras were
created, in which each single transmembrane domain of hEag1 was replaced by the corresponding segment of hEag2. The voltage-dependent
properties of the chimaeras were analysed after expression in Xenopus laevis oocytes using the two-electrode voltage-clamp method. By this we found, that only the mutations in transmembrane domains
S5 and S6 are able to change the voltage sensitivity of hEag1 by shifting the half-activation potential (V
50) to values intermediate between the two wild types. Moreover, the presence of Mg2+ has strong effects on the voltage sensitivity of hEag2 shifting V
50 by more than 50 mV to more positive values. Interestingly, despite the identical binding site Mg2+ showed only little effects on hEag1 or the chimaeras. Altogether, our data suggest that not only transmembrane spanning regions,
but also non-membrane spanning regions are responsible for differences in the behaviour of the hEag1 and hEag2 potassium channels.
EBSA Satellite meeting: Ion channels, Leeds, July 2007. 相似文献
189.
Sexual size dimorphism (SSD) is often assumed to be driven by three major selective processes: (1) sexual selection influencing male size and thus mating success, (2) fecundity selection acting on females and (3) inter‐sexual resource division favouring different size in males and females to reduce competition for resources. Sexual selection should be particularly strong in species that exhibit lek polygyny, since male mating success is highly skewed in such species. We investigated whether these three selective processes are related to SSD evolution in grouse and allies (Phasianidae). Male‐biased SSD increased with body size (Rensch’s rule) and lekking species exhibited more male‐biased SSD than nonlekking ones. Directional phylogenetic analyses indicated that lekking evolved before SSD, but conclusions were highly dependent on the body size traits and chosen model values. There was no relationship between SSD and male display agility, nor did resource division influence SSD. Although clutch mass increased with female body size it was not related to the degree of SSD. Taken together, the results are most consistent with the hypothesis that lekking behaviour led to the evolution of male‐biased SSD in Phasianidae. 相似文献
190.
MARC PHILIPPE HONG‐EN JIANG KYUNGSIK KIM CHANGHWAN OH DMITRY GROMYKO MELISE HARLAND IN‐SUNG PAIK FREDERIC THÉVENARD 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2009,42(4):393-406
Although the faunal elements of Far East Asian Mesozoic terrestrial biota have attracted much attention in recent years, their palaeoecology remains poorly known. In particular, features of the palaeoclimate are highly controversial. To address this point we used the Mesozoic fossil wood Xenoxylon , a genus recognized as an indicator of wet temperate biotopes and which is common in the area during the Carnian–Maastrichtian interval. We re-appraised bibliographic data and gathered new data for Xenoxylon in the Mesozoic of Far East Asia. This demonstrated that previous taxonomic approaches to the genus have been so far idiosyncratic. We examined the anatomical diversity of morphogenus Xenoxylon in Far East Asia and compared it to that of samples from Europe. This indicates that in an area centred on north-eastern China, Xenoxylon reached a level of anatomical diversity unmatched elsewhere in the world. We hypothesize that this diversity witnesses the persistence of palaeoecological conditions particularly suitable for Xenoxylon and that a wet temperate climate prevailed over most of the area throughout the Carnian–Maastrichtian interval. It is in this setting that the famous Jehol Biota probably evolved. 相似文献