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1.
F Hirsch S Germana K Gustafsson K Pratt D H Sachs C Leguern 《Journal of immunology (Baltimore, Md. : 1950)》1992,149(3):841-846
Two overlapping genomic clones corresponding to the swine DRA class II gene were isolated and characterized. Restriction mapping and partial sequence data of the exon-containing fragments allowed identification and orientation of the five exons encoding the alpha chain. Two full length cDNA clones corresponding to the transcribed DRA gene from two different haplotypes of the swine MHC were sequenced. Nucleotide sequence alignments revealed that the two swine DRA cDNA were very similar and closely related to the human DRA equivalent. An additional glycosylation site, compared with those of human DRA, was found in the second external domain of the protein. Northern analyses showed that porcine DRA and DQA genes were the only two class II alpha genes expressed in the spleen, despite the presence of DPA and DZA genes in the genome. In addition to transfected cells expressing homologous pairs of alpha and beta chains from SLA-DR, stable transfectants expressing nonhomologous pairs of alpha and beta chains from DR and DQ loci were obtained, suggesting that such associations may contribute to the functional heterogeneity of class II products. 相似文献
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Christopher B. Ruff Evan Garofalo Megan A. Holmes 《American journal of physical anthropology》2013,150(1):29-37
The study of juvenile skeletal remains can yield important insights into the health, behavior, and biological relationships of past populations. However, most studies of past skeletal growth have been limited to relatively simple metrics. Considering additional skeletal parameters and taking a broader physiological perspective can provide a more complete assessment of growth patterns and environmental and genetic effects on those patterns. We review here some alternative approaches to ontogenetic studies of archaeological and paleontological skeletal material, including analyses of body size (stature and body mass) and cortical bone structure of long bone diaphyses and the mandibular corpus. Together such analyses can shed new light on both systemic and localized influences on bone growth, and the metabolic and mechanical factors underlying variation in growth. Am J Phys Anthropol, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
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Luigi Piero Stasi Roberto Artusi Clara Bovino Benedetta Buzzi Luca Canciani Gianfranco Caselli Fabrizio Colace Paolo Garofalo Silvia Giambuzzi Patrice Larger Ornella Letari Stefano Mandelli Lorenzo Perugini Sabrina Pucci Matteo Salvi PierLuigi Toro 《Bioorganic & medicinal chemistry letters》2013,23(9):2653-2658
Starting from a orexin 1 receptor selective antagonist 4,4-disubstituted piperidine series a novel potent 5-azaspiro[2.4]heptane dual orexin 1 and orexin 2 receptor antagonist class has been discovered. SAR and Pharmacokinetic optimization of this series is herein disclosed. Lead compound 15 exhibits potent activity against orexin 1 and orexin 2 receptors along with low cytochrome P450 inhibition potential, good brain penetration and oral bioavailability in rats. 相似文献
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Valentina Sanghez Maria Teresa Russo Maria Antonietta Ajmone‐Cat Emanuele Cacci Alberto Martire Patrizia Popoli Germana Falcone Flavia Michelini Marco Crescenzi Paolo Degan Luisa Minghetti Margherita Bignami Gemma Calamandrei 《Aging cell》2013,12(4):695-705
The contribution that oxidative damage to DNA and/or RNA makes to the aging process remains undefined. In this study, we used the hMTH1‐Tg mouse model to investigate how oxidative damage to nucleic acids affects aging. hMTH1‐Tg mice express high levels of the hMTH1 hydrolase that degrades 8‐oxodGTP and 8‐oxoGTP and excludes 8‐oxoguanine from both DNA and RNA. Compared to wild‐type animals, hMTH1‐overexpressing mice have significantly lower steady‐state levels of 8‐oxoguanine in both nuclear and mitochondrial DNA of several organs, including the brain. hMTH1 overexpression prevents the age‐dependent accumulation of DNA 8‐oxoguanine that occurs in wild‐type mice. These lower levels of oxidized guanines are associated with increased longevity and hMTH1‐Tg animals live significantly longer than their wild‐type littermates. Neither lipid oxidation nor overall antioxidant status is significantly affected by hMTH1 overexpression. At the cellular level, neurospheres derived from adult hMTH1‐Tg neural progenitor cells display increased proliferative capacity and primary fibroblasts from hMTH1‐Tg embryos do not undergo overt senescence in vitro. The significantly lower levels of oxidized DNA/RNA in transgenic animals are associated with behavioral changes. These mice show reduced anxiety and enhanced investigation of environmental and social cues. Longevity conferred by overexpression of a single nucleotide hydrolase in hMTH1‐Tg animals is an example of lifespan extension associated with healthy aging. It provides a link between aging and oxidative damage to nucleic acids. 相似文献
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Mark F. Santos Germana Rappa Jana Karbanov Cheryl Vanier Chikao Morimoto Denis Corbeil Aurelio Lorico 《Journal of cellular and molecular medicine》2019,23(6):4408-4421
The intercellular communication mediated by extracellular vesicles (EVs) has gained international interest during the last decade. Interfering with the mechanisms regulating this cellular process might find application particularly in oncology where cancer cell‐derived EVs play a role in tumour microenvironment transformation. Although several mechanisms were ascribed to explain the internalization of EVs, little is our knowledge about the fate of their cargos, which are crucial to mediate their function. We recently demonstrated a new intracellular pathway in which a fraction of endocytosed EV‐associated proteins is transported into the nucleoplasm of the host cell via a subpopulation of late endosomes penetrating into the nucleoplasmic reticulum. Silencing tetraspanin CD9 both in EVs and recipient cells strongly decreased the endocytosis of EVs and abolished the nuclear transfer of their cargos. Here, we investigated whether monovalent Fab fragments derived from 5H9 anti‐CD9 monoclonal antibody (referred hereafter as CD9 Fab) interfered with these cellular processes. To monitor the intracellular transport of proteins, we used fluorescent EVs containing CD9‐green fluorescent protein fusion protein and various melanoma cell lines and bone marrow‐derived mesenchymal stromal cells as recipient cells. Interestingly, CD9 Fab considerably reduced EV uptake and the nuclear transfer of their proteins in all examined cells. In contrast, the divalent CD9 antibody stimulated both events. By impeding intercellular communication in the tumour microenvironment, CD9 Fab‐mediated inhibition of EV uptake, combined with direct targeting of cancerous cells could lead to the development of novel anti‐melanoma therapeutic strategies. 相似文献
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Gianpiero Di Leva Claudia Piovan Pierluigi Gasparini Apollinaire Ngankeu Cristian Taccioli Daniel Briskin Douglas G. Cheung Brad Bolon Laura Anderlucci Hansjuerg Alder Gerard Nuovo Meng Li Marilena V. Iorio Marco Galasso Santhanam Ramasamy Guido Marcucci Danilo Perrotti Kimerly A. Powell Anna Bratasz Michela Garofalo Kenneth P. Nephew Carlo M. Croce 《PLoS genetics》2013,9(3)
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Germana Bueno Dias Valdirene Moreira Gomes Umberto Zottich Pereira Suzanna F. Ferreira Ribeiro André O. Carvalho Rosana Rodrigues Olga L. Tavares Machado Kátia Valevski Sales Fernandes André Teixeira S. Ferreira Jonas Perales Maura Da Cunha 《The protein journal》2013,32(1):15-26
Capsicum species belong to the Solanaceae family and have great social, economic and agronomical significance. The present research presents data on the isolation and characterization of Capsicum chinense Jacq. peptides which were scrutinized in relation to their toxicity towards a diverse set of yeast species. The protein extract was separated with C18 reverse-phase chromatography in high performance liquid chromatography, resulting in three different peptide enriched fractions (PEFs) termed PEF1, PEF2 and PEF3. Tricine-SDS-PAGE of the PEF2 revealed peptides with molecular masses of approximately 5.0 and 8.5 kDa. These PEFs also exhibited strong antifungal activity against different yeasts. In the presence of the PEF2, Candida tropicalis exhibited morphological changes, including cellular agglomeration and formation of pseudohyphae. Determined N-terminal sequences of PEF2 and PEF3 were proven to be highly homologous to serine proteinase inhibitors, when analysed by comparative database sequence tools. For this reason were performed protease inhibitory activity assay. The PEFs displayed high inhibitory activity against trypsin and low inhibitory activity against chymotrypsin. PEF2 and PEF3 were considerably unsusceptible to a broad interval of pH and temperatures. Due to the myriad of application of Proteinase inhibitors (PIs) in fields ranging from plant protection against pathogens and pests to medicine such as in cancer and virus replication inhibition, the discovery of new PIs with new properties are of great interest. 相似文献