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141.
Larrubia JR Benito-Martínez S Miquel J Calvino M Sanz-de-Villalobos E González-Praetorius A Albertos S García-Garzón S Lokhande M Parra-Cid T 《Cellular immunology》2011,269(2):104-114
PD-1 molecule promotes anergy and IL-7 receptor (CD127) induces an anti-apoptotic effect on T cells. Correlation between PD-1/CD127 phenotype and hepatitis C virus (HCV)-specific CD8+ cell reactivity in resolved infection (RI) after treatment and persistent HCV-infection (PI) was analysed. Directly ex vivo, PD-1 and CD127 expression on HCV-specific CD8+ cells displayed a positive and negative correlation, respectively with viraemia. Proliferation after stimulation on PD-1−/CD127+ cells from RI cases was preserved, while it was impaired on PD-1+/CD127− cells from PI patients. PD1+/CD127+ population was observed in PI, and these maintained expansion ability but they did not target the virus. Frequency of PI cases with HCV-specific CD8+ cell proliferation increased after anti-PD-L1 and anti-apoptotic treatment. Bim expression on HCV-specific CD8+ cells from PI patients was enhanced. In conclusion, during chronic HCV infection non-reactive HCV-specific CD8+ cells targeting the virus are PD-1+/CD127−/Bim+ and, blocking apoptosis and PD-1/PD-L1 pathway on them enhances in vitro reactivity. 相似文献
142.
González-Díaz H Prado-Prado F García-Mera X Alonso N Abeijón P Caamaño O Yáñez M Munteanu CR Pazos A Dea-Ayuela MA Gómez-Muñoz MT Garijo MM Sansano J Ubeira FM 《Journal of proteome research》2011,10(4):1698-1718
Many drugs with very different affinity to a large number of receptors are described. Thus, in this work, we selected drug-target pairs (DTPs/nDTPs) of drugs with high affinity/nonaffinity for different targets. Quantitative structure-activity relationship (QSAR) models become a very useful tool in this context because they substantially reduce time and resource-consuming experiments. Unfortunately, most QSAR models predict activity against only one protein target and/or they have not been implemented on a public Web server yet, freely available online to the scientific community. To solve this problem, we developed a multitarget QSAR (mt-QSAR) classifier combining the MARCH-INSIDE software for the calculation of the structural parameters of drug and target with the linear discriminant analysis (LDA) method in order to seek the best model. The accuracy of the best LDA model was 94.4% (3,859/4,086 cases) for training and 94.9% (1,909/2,012 cases) for the external validation series. In addition, we implemented the model into the Web portal Bio-AIMS as an online server entitled MARCH-INSIDE Nested Drug-Bank Exploration & Screening Tool (MIND-BEST), located at http://miaja.tic.udc.es/Bio-AIMS/MIND-BEST.php . This online tool is based on PHP/HTML/Python and MARCH-INSIDE routines. Finally, we illustrated two practical uses of this server with two different experiments. In experiment 1, we report for the first time a MIND-BEST prediction, synthesis, characterization, and MAO-A and MAO-B pharmacological assay of eight rasagiline derivatives, promising for anti-Parkinson drug design. In experiment 2, we report sampling, parasite culture, sample preparation, 2-DE, MALDI-TOF and -TOF/TOF MS, MASCOT search, 3D structure modeling with LOMETS, and MIND-BEST prediction for different peptides as new protein of the found in the proteome of the bird parasite Trichomonas gallinae, which is promising for antiparasite drug targets discovery. 相似文献
143.
Birkenfeld AL Lee HY Guebre-Egziabher F Alves TC Jurczak MJ Jornayvaz FR Zhang D Hsiao JJ Martin-Montalvo A Fischer-Rosinsky A Spranger J Pfeiffer AF Jordan J Fromm MF König J Lieske S Carmean CM Frederick DW Weismann D Knauf F Irusta PM De Cabo R Helfand SL Samuel VT Shulman GI 《Cell metabolism》2011,14(2):184-195
Reduced expression of the Indy (I'm Not Dead, Yet) gene in D.?melanogaster and its homolog in C.?elegans prolongs life span and in D.?melanogaster augments mitochondrial biogenesis in a manner akin to caloric restriction. However, the cellular mechanism by which Indy does this is unknown. Here, we report on the knockout mouse model of the mammalian Indy (mIndy) homolog, SLC13A5. Deletion of mIndy in mice (mINDY(-/-) mice) reduces hepatocellular ATP/ADP ratio, activates hepatic AMPK, induces PGC-1α, inhibits ACC-2, and reduces SREBP-1c levels. This signaling network promotes hepatic mitochondrial biogenesis, lipid oxidation, and energy expenditure and attenuates hepatic de novo lipogenesis. Together, these traits protect mINDY(-/-) mice from the adiposity and insulin resistance that evolve with high-fat feeding and aging. Our studies demonstrate a profound effect of mIndy on mammalian energy metabolism and suggest that mINDY might be a therapeutic target for the treatment of obesity and type 2 diabetes. 相似文献
144.
Methicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen in both human and veterinary medicine. The importance of companion animals as reservoirs of human infections is currently unknown. The companion animals of 49 MRSA-infected outpatients (cases) were screened for MRSA carriage, and their bacterial isolates were compared with those of the infected patients using Pulsed-Field Gel Electrophoresis (PFGE). Rates of MRSA among the companion animals of MRSA-infected patients were compared to rates of MRSA among companion animals of pet guardians attending a “veterinary wellness clinic” (controls). MRSA was isolated from at least one companion animal in 4/49 (8.2%) households of MRSA-infected outpatients vs. none of the pets of the 50 uninfected human controls. Using PFGE, patient-pets MRSA isolates were identical for three pairs and discordant for one pair (suggested MRSA inter-specie transmission p-value = 0.1175). These results suggest that companion animals of MRSA-infected patients can be culture-positive for MRSA, representing a potential source of infection or re-infection for humans. Further studies are required to better understand the epidemiology of MRSA human-animal inter-specie transmission. 相似文献
145.
Uncovering species boundaries in the Neotropical ant complex Ectatomma ruidum (Ectatomminae) under the presence of nuclear mitochondrial paralogues 下载免费PDF全文
Reina Gabriela Aguilar‐Velasco Chantal Poteaux Rubi Meza‐Lázaro Jean‐Paul Lachaud Dmitry Dubovikoff Alejandro Zaldívar‐Riverón 《Zoological Journal of the Linnean Society》2016,178(2):226-240
Nuclear mitochondrial (mt) paralogues (numts) are non‐functional fragments of mtDNA integrated into the nuclear genome that can overestimate the number of species in analyses based on mtDNA sequences. As numts have relatively slow mutation rates, they can pass undetected by conventional procedures such as inspecting for internal stop codons, indels or apparent polymorphism in chromatograms. Species boundaries based on mtDNA markers therefore require a thorough assessment of numts, especially in insects, where this phenomenon appears to be relatively frequent. Ectatomma ruidum is a widely distributed Neotropical ant species that is distributed from northern Mexico to northern Brazil. Previous behavioural and molecular evidence suggests that this species actually represents a composite taxon. Here we assessed the species boundaries in E. ruidum based on two mt (COI, cyt b) and one nuclear (H3) marker, as well as on external morphology. Ancient and recent mt paralogues were detected in several specimens, although pre‐PCR dilution of DNA template helped to recover most of the mt orthologues. Based on the congruence found between our species delineation obtained from the mt genealogies and the discriminated morphospecies, we propose that E. ruidum is actually composed of at least three species. Two of these species have a wide geographical distribution in the Neotropics, whereas the remaining one was restricted to localities situated near the Pacific coast in south‐east Mexico. We also found extensive intra‐ and interspecific variation in the barcoding locus. Moreover, the nuclear evidence suggests the existence of hybrids between two of these species in Oaxaca, south‐east Mexico. This study agrees with previous studies of other closely related animal taxa, which have revealed a complex evolutionary history and overlooked species diversity in the latter region. 相似文献
146.
Fusion of native or reconstituted membranes to liposomes, optimized for single channel recording. 下载免费PDF全文
We here describe a protocol for fusing vesicles into large structures suitable for patch clamp recording. The method may be used with native membrane vesicles or with liposomes containing reconstituted/purified ion channels. The resulting unilamellar membranes exhibit high channel surface abundance, yielding multiple channels in the average excised patch. The procedure has been used to record voltage-sensitive Na channels from three native membrane preparations (eel electroplax, rat skeletal muscle, squid optic nerve), and from reconstituted protein purified from eel electroplax. Channels treated with batrachotoxin (BTX) displayed characteristic activation voltage dependence, conductances, selectivity, and sensitivity to saxitoxin (STX). 相似文献
147.
148.
Jamille Karina Coelho Correa Emil José Hernández-Ruz Marcos Tobias de Santana Miglionico Lúcio André Viana 《Systematic parasitology》2018,95(2-3):319-324
A new coccidian species of the genus Isospora Schneider 1881 (Apicomplexa, Eimeriidae) is reported from a single specimen of chelid turtle, Platemys platycephala (Schneider, 1792), obtained in a flooded area of the Amazonian municipality of Altamira, in Pará State, northern Brazil. The oöcysts of Isospora platemysi n. sp. are subspheroidal, 19.0–24.0 × 22.5–18.5 (22.6 × 20.8) µm in size [length/width ratio 1.0–1.1 (1.1)], with a colourless wall, 1.0–1.9 (1.4) wide, with two smooth layers; polar granule is present, oöcyst residuum and micropyle are both absent. The sporocyst is ovoidal, 10.0–12.1 × 8.0–10.0 (11.0 × 9.1) µm [length/width ratio 1.1–1.3 (1.2), with a knob-like Stieda body. Sub-Stieda body is present, rounded irregular-trapezoidal; para-Stieda body is absent. Sporocyst residuum is dispersed and composed of granules of differing sizes. This is only the fifth record of Isospora in chelonians, and the first report of a coccidian parasite of the genus Platemys. 相似文献
149.
Robert L. Brownell Jr. Lloyd T. Findley Omar Vidal Alejandro Robles Silvia Manzanilla N 《Marine Mammal Science》1987,3(1):22-30
The vaquita, Phocoena sinus , is a porpoise in the family Phocoenidae that lives only in the Gulf of California. The external appearance of P. sinus was unknown until 13 fresh specimens were recently examined. The most obvious morphological feature distinguishing P. sinus from its two congeners is the proportionately higher dorsal fin. The most striking features of the pigmentation pattern are the large black eye patches and the black upper and lower lip patches. In both areas, the pigmentation contrasts sharply with the surrounding light gray coloration. The total lengths of the specimens ranged from 70.3 cm (a neonate) to 143.5 cm (an adult female). 相似文献
150.
Javier A. Arata Alejandro R. Vila Ricardo Matus Daniela Droguett Carlos Silva-Quintas Valeria Falabella Graham Robertson Daniela Haro 《Polar Biology》2014,37(4):565-571
Black-browed albatrosses are the most abundant albatross species of the southern hemisphere, breeding on sub-Antarctic and Antarctic oceanic islands around the globe. Their foraging habitat during the breeding season is reasonably well known along its distributional range, indicating a preferred use of waters <500 m deep. The discovery of a colony inserted within the Admiralty Sound, Tierra del Fuego, poses an interesting challenge to the known precepts on foraging behavior for the species. In this study, we present the first record on the foraging distribution of the only known inner-channel colony of albatrosses in the world, using high-resolution GPS loggers. Black-browed albatrosses breeding at the Albatross Islet used exclusively inner-channel waters, at least during the chick-guard stage. Our results indicate a significant smaller foraging range during chick-guard compared with conspecifics from Diego Ramirez and Falklands/Malvinas Islands. Implications for the conservation of this colony are discussed. 相似文献