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Wen Zhang Jinsong Tang A-Mei Zhang Min-Sheng Peng Hai-Bing Xie Liwen Tan Lin Xu Ya-Ping Zhang Xiaogang Chen Yong-Gang Yao 《遗传学报》2014,41(7):397-407
Mitochondrial dysfunction has been widely reported in schizophrenia patients. To dissect the matrilineal structure of Han Chinese with or without schizophrenia and to decipher the maternal influence and evolutionary history of schizophrenia, a total of 1212 schizophrenia patients and 1005 matched healthy controls, all of Han Chinese origin, were recruited in Hunan Province, China. We classified haplogroup for each individual based on mitochondrial DNA (mtDNA) sequence variations and compared the haplogroup distribution pattern between cases and controls. Haplogroup B5a presented a higher frequency in cases than in controls (P = 0.02, OR = 1.67, 95% CI = [1.09, 2.56]), and this result could be confirmed by permutation analysis. Age estimation of haplogroup B5a in cases revealed a much younger age than that of controls, which was coincident with the Northern Hemisphere deglaciation at the end of the Last Glacial Maximum. Analysis of complete mtDNA in five patients belonging to haplogroup B5a showed that this background effect might be caused by haplogroup- defining variants m.8584G〉A and m.10398A〉G. Our results showed that matrilineal risk factor for schizophrenia had an ancient origin and might acquire a predisposing effect on schizophrenia due to the environment change and/or orchestration with other nuclear genetic factors appeared recently in human evolutionary history. 相似文献
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Rocío Rodríguez-López Armando Reyes-Palomares Francisca Sánchez-Jiménez Miguel ángel Medina 《BMC bioinformatics》2014,15(1)
Background
Several types of genetic interactions in humans can be directly or indirectly associated with the causal effects of mutations. These interactions are usually based on their co-associations to biological processes, coexistence in cellular locations, coexpression in cell lines, physical interactions and so on. In addition, pathological processes can present similar phenotypes that have mutations either in the same genomic location or in different genomic regions. Therefore, integrative resources for all of these complex interactions can help us prioritize the relationships between genes and diseases that are most deserving to be studied by researchers and physicians.Results
PhenUMA is a web application that displays biological networks using information from biomedical and biomolecular data repositories. One of its most innovative features is to combine the benefits of semantic similarity methods with the information taken from databases of genetic diseases and biological interactions. More specifically, this tool is useful in studying novel pathological relationships between functionally related genes, merging diseases into clusters that share specific phenotypes or finding diseases related to reported phenotypes.Conclusions
This framework builds, analyzes and visualizes networks based on both functional and phenotypic relationships. The integration of this information helps in the discovery of alternative pathological roles of genes, biological functions and diseases. PhenUMA represents an advancement toward the use of new technologies for genomics and personalized medicine.Electronic supplementary material
The online version of this article (doi:10.1186/s12859-014-0375-1) contains supplementary material, which is available to authorized users. 相似文献5.
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Our understanding of the mitochondrial or intrinsic apoptosis pathway and its role in chemotherapy resistance has increased significantly in recent years by a combination of experimental studies and mathematical modelling. This combined approach enhanced the quantitative and kinetic understanding of apoptosis signal transduction, but also provided new insights that systems-emanating functions (i.e., functions that cannot be attributed to individual network components but that are instead established by multi-component interplay) are crucial determinants of cell fate decisions. Among these features are molecular thresholds, cooperative protein functions, feedback loops and functional redundancies that provide systems robustness, and signalling topologies that allow ultrasensitivity or switch-like responses. The successful development of kinetic systems models that recapitulate biological signal transduction observed in living cells have now led to the first translational studies, which have exploited and validated such models in a clinical context. Bottom-up strategies that use pathway models in combination with higher-level modelling at the tissue, organ and whole body-level therefore carry great potential to eventually deliver a new generation of systems-based diagnostic tools that may contribute to the development of personalised and predictive medicine approaches. Here we review major achievements in the systems biology of intrinsic apoptosis signalling, discuss challenges for further model development, perspectives for higher-level integration of apoptosis models and finally discuss requirements for the development of systems medical solutions in the coming years. 相似文献
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C. N. Bouza 《Biometrical journal. Biometrische Zeitschrift》1985,27(7):799-805
The Random Response Design is used for obtaining information from the non respondents. The existence of a refusal to respond may be the cause of non responses. The model obtained seems to be a good alternative for reducing non sampling errors due to dishonest answers. 相似文献
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Jane Hall Andrew H. Jheon Erin L. Ealba B. Frank Eames Kristin D. Butcher Siu-Shan Mak Raj Ladher Tamara Alliston Richard A. Schneider 《Developmental biology》2014
Neural crest mesenchyme (NCM) controls species-specific pattern in the craniofacial skeleton but how this cell population accomplishes such a complex task remains unclear. To elucidate mechanisms through which NCM directs skeletal development and evolution, we made chimeras from quail and duck embryos, which differ markedly in their craniofacial morphology and maturation rates. We show that quail NCM, when transplanted into duck, maintains its faster timetable for development and autonomously executes molecular and cellular programs for the induction, differentiation, and mineralization of bone, including premature expression of osteogenic genes such as Runx2 and Col1a1. In contrast, the duck host systemic environment appears to be relatively permissive and supports osteogenesis independently by providing circulating minerals and a vascular network. Further experiments reveal that NCM establishes the timing of osteogenesis by regulating cell cycle progression in a stage- and species-specific manner. Altering the time-course of D-type cyclin expression mimics chimeras by accelerating expression of Runx2 and Col1a1. We also discover higher endogenous expression of Runx2 in quail coincident with their smaller craniofacial skeletons, and by prematurely over-expressing Runx2 in chick embryos we reduce the overall size of the craniofacial skeleton. Thus, our work indicates that NCM establishes species-specific size in the craniofacial skeleton by controlling cell cycle, Runx2 expression, and the timing of key events during osteogenesis. 相似文献
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Defending Robert Rosen's claim that in every confrontation between physics and biology it is physics that has always had to give ground, it is shown that many of the most important advances in mathematics and physics over the last two centuries have followed from Schelling's demand for a new physics that could make the emergence of life intelligible. Consequently, while reductionism prevails in biology, many biophysicists are resolutely anti-reductionist. This history is used to identify and defend a fragmented but progressive tradition of anti-reductionist biomathematics. It is shown that the mathematico–physico–chemical morphology research program, the biosemiotics movement, and the relational biology of Rosen, although they have developed independently of each other, are built on and advance this anti-reductionist tradition of thought. It is suggested that understanding this history and its relationship to the broader history of post-Newtonian science could provide guidance for and justify both the integration of these strands and radically new work in post-reductionist biomathematics. 相似文献
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U. Majumdar 《水生昆虫》2013,35(3):253-272
Three new species, Glyptotendipes (Glyptotendipes) fumilatus, G. (G.) ingenius and G. (G.) validens are described. A short account of habitat, construction of dwellings, food and feeding of the larva and emergence of the adult has also been appended. A new dichotomous key to the Indian species is provided. 相似文献
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Population and reproductive biology of Uca thayeri Rathbun, 1900 were studied for the first time in a tropical mangrove. Absolute density, sex ratio, population structure, handedness, breeding season and fecundity were investigated. Seven transects were delimited in a mangrove area of the Pacoti River, Northeast of Brazil (3° 43′ 02″ S/38° 32′ 35″ W). On each transect, ten 0.25 m2 squares were sampled on a monthly basis during low tide periods from September 2003 to August 2004. A total of 483 crabs were obtained, of which 250 were males, 219 non-ovigerous females, and 14 ovigerous females. The U. thayeri population presented bi-modal size frequency distribution, with males and non-ovigerous females not differing significantly size-wise. Ovigerous females were larger than males and non-ovigerous females. The overall sex ratio (1:1.07) did not differ significantly from the expected 1:1 proportion. The major cheliped was the right one in 50% of the males. The observed density was of 8.5 individuals/m2, with the specimens being found mostly in shaded areas. Ovigerous females were found in 5 months of the year, coinciding with the rainy season, suggesting that the population of U. thayeri presents seasonal reproductive events. Juvenile crabs were more abundant during the dry period, while larger crabs were found mainly during the rainy period. The fecundity of the studied population was much smaller than that of subtropical populations of this species. The regression analysis shows that the number of eggs increases linearly with the increase of carapace width. 相似文献
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Taxonomy of a tetrigid genus Teredorus Hancock is reviewed. Two new species, Teredorus parvipulvillussp. n. and Teredorus hunanensissp. n. are described from China and an updated identification key to all known species of the genus is given, as well as brief comments on phylogenetic relationships, biology and ecology. 相似文献
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D. EDWARDS F.L.S. U. FANNING K. L. DAVIES L. AXE J. B. RICHARDSON 《Botanical journal of the Linnean Society. Linnean Society of London》1995,117(4):233-254
Reniform sporangia, comprising two equal valves and containing retusoid spores, recovered from Lower Old Red Sandstone strata of Devonian age ( micrornatus-newportensis Spore Biozone: lower Gedinnian lower Lochkovian) on North Brown Clee Hill in the Welsh Borderland are placed in Resilitheca salopensis gen. et sp. nov. Conventional compression fossils from Targrove, Ludlow of fertile axes showing isotomous branching with limited overtopping are considered conspecific because the terminal reniform sporangia contain the same spores. Spore ultrastructure is described using scanning and transmission electron microscopy. Sections show faint traces of lamellae. Particles associated with spores and sporangium wall are compared with the globules of pteridophytes and Ubisch bodies of angiosperms, and related to the development of the sporangium. The new plants are compared with Cooksonia caledonica Edwards known only from impressions, and with Renalia Gensel showing far more pronounced pseudomonopodial branching. 相似文献
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Ponds support a rich biodiversity because the heterogeneity of individual ponds creates, at the landscape scale, a diversity
of habitats for wildlife. The distribution of pond animals and plants will be influenced by both the local conditions within
a pond and the spatial distribution of ponds across the landscape. Separating out the local from the spatial is difficult
because the two are often linked. Pond snails are likely to be affected by both local conditions, e.g. water hardness, and
spatial patterns, e.g. distance between ponds, but studies of snail communities struggle distinguishing between the two. In
this study, communities of snails were recorded from 52 ponds in a biogeographically coherent landscape in north-east England.
The distribution of snail communities was compared to local environments characterised by the macrophyte communities within
each pond and to the spatial pattern of ponds throughout the landscape. Mantel tests were used to partial out the local versus
the landscape respective influences. Snail communities became more similar in ponds that were closer together and in ponds
with similar macrophyte communities as both the local and the landscape scale were important for this group of animals. Data
were collected from several types of ponds, including those created on nature reserves specifically for wildlife, old field
ponds (at least 150 years old) primarily created for watering livestock and subsidence ponds outside protected areas or amongst
coastal dunes. No one pond type supported all the species. Larger, deeper ponds on nature reserves had the highest numbers
of species within individual ponds but shallow, temporary sites on farm land supported a distinct temporary water fauna. The
conservation of pond snails in this region requires a diversity of pond types rather than one idealised type and ponds scattered
throughout the area at a variety of sites, not just concentrated on nature reserves.
Handling editor: B. Oertli 相似文献
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Abstract: This study tested immunogenicity of a synthetic peptide hZP3327–341 from a human zona pellucida (ZP) glycoprotein. After antibody response to various peptide-carrier conjugates was assessed in mice, two female cynomolgus macaques were immunized with the peptide conjugated to keyhole limpet hemocyanin (KLH). A control macaque was immunized with KLH. The peptide was immunogenic in both species, and included both B and T cell epitopes since low to moderate titers of peptide-specific antibodies and a T cell proliferative response were measured. Profiles of ovarian steroid metabolites indicated unchanged ovarian function in the macaques, but only the control conceived when bred. Ovarian histology was normal except that immunoglobulin was bound to ZP in follicles of the peptide-immune macaques. ZP from these females bound sperm and induced acrosome reactions at rates equal to those of an untreated control. The results support the feasibility of an immunocontraceptive vaccine based on autologous ZP peptides. 相似文献
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Miroslaw Ksiazek Danuta Mizgalska Jan J. Enghild Carsten Scavenius Ida B. Thogersen Jan Potempa 《The Journal of biological chemistry》2015,290(1):658-670
All prokaryotic genes encoding putative serpins identified to date are found in environmental and commensal microorganisms, and only very few prokaryotic serpins have been investigated from a mechanistic standpoint. Herein, we characterized a novel serpin (miropin) from the human pathogen Tannerella forsythia, a bacterium implicated in initiation and progression of human periodontitis. In contrast to other serpins, miropin efficiently inhibited a broad range of proteases (neutrophil and pancreatic elastases, cathepsin G, subtilisin, and trypsin) with a stoichiometry of inhibition of around 3 and second-order association rate constants that ranged from 2.7 × 104 (cathepsin G) to 7.1 × 105
m−1s−1 (subtilisin). Inhibition was associated with the formation of complexes that were stable during SDS-PAGE. The unusually broad specificity of miropin for target proteases is achieved through different active sites within the reactive center loop upstream of the P1-P1′ site, which was predicted from an alignment of the primary structure of miropin with those of well studied human and prokaryotic serpins. Thus, miropin is unique among inhibitory serpins, and it has apparently evolved the ability to inhibit a multitude of proteases at the expense of a high stoichiometry of inhibition and a low association rate constant. These characteristics suggest that miropin arose as an adaptation to the highly proteolytic environment of subgingival plaque, which is exposed continually to an array of host proteases in the inflammatory exudate. In such an environment, miropin may function as an important virulence factor by protecting bacterium from the destructive activity of neutrophil serine proteases. Alternatively, it may act as a housekeeping protein that regulates the activity of endogenous T. forsythia serine proteases. 相似文献