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Fei Mi Ying Zhang Dan Yang Xiaozhao Tang Pengfei Wang Xiaoxia He Yunrun Zhang Jianyong Dong Yang Cao Chunli Liu Ke-Qin Zhang Jianping Xu 《PloS one》2016,11(2)
During the past 40 years, more than 400 Sudden Unexplained Deaths (SUDs) have occurred in Yunnan, southwestern China. Epidemiological and toxicological analyses suggested that a newly discovered mushroom called Trogia venenata was the leading culprit for SUDs. At present, relatively little is known about the genetics and natural history of this mushroom. In this study, we analyzed the sequence variation at four DNA fragments among 232 fruiting bodies of T. venenata collected from seven locations. Our ITS sequence analyses confirmed that all the isolates belonged to the same species. The widespread presence of sequence heterozygosity within many strains at each of three protein-coding genes suggested that the fruiting bodies were diploid, dikaryotic or heterokaryotic. Within individual geographic populations, we found significant deviations of genotype frequencies from Hardy-Weinberg expectations, with the overall observed heterozygosity lower than that expected under random mating, consistent with prevalent inbreeding within local populations. The geographic populations were overall genetically differentiated. Interestingly, while a positive correlation was found between population genetic distance and geographic distance, there was little correlation between genetic distance and barium concentration difference for the geographic populations. Our results suggest frequent inbreeding, geographic structuring, and limited gene flow among geographic populations of T. venenata from southwestern China. 相似文献
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Ovarian cancer G protein-coupled receptor 1 (OGR1) is a proton-sensing molecule that can detect decreases in extracellular pH that occur during inflammation. Although OGR1 has been shown to have pro-inflammatory functions in various diseases, its role in autoimmunity has not been examined. We therefore sought to determine whether OGR1 has a role in the development of T cell autoimmunity by contrasting the development of experimental autoimmune encephalomyelitis between wild type and OGR1-knockout mice. OGR1-knockout mice showed a drastically attenuated clinical course of disease that was associated with a profound reduction in the expansion of myelin oligodendrocyte glycoprotein 35-55-reactive T helper 1 (Th1) and Th17 cells in the periphery and a reduced accumulation of Th1 and Th17 effectors in the central nervous system. We determined that these impaired T cell responses in OGR1-knockout mice associated with a reduced frequency and number of dendritic cells in draining lymph nodes during EAE and a higher production of nitric oxide by macrophages. Our studies suggest that OGR1 plays a key role in regulating T cell responses during autoimmunity. 相似文献
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Abstract All ants (Hymenoptera, Formicidae) are highly eusocial insects that are characterized by reproductive division of labor with sterile castes (worker and soldier) helping fertile castes (queen and male) to reproduce.
Ant societies, like other complex animal societies, have developed a sophisticated communication system, in which recognition behaviors are frequently involved Recognition abilities allow individuals to orient and modulate their behaviors effectively and appropriately in response to the characteristics andlor signals expressed by other organisms. Among recognition behaviors, nestmate recognition and kin recognition mechanisms have attracted great attention of sociobiologists, ecologists, insect physiologists and biochemists since 1970's. This is parallel with the popularization of Hamilton's kin selection theory. The present paper aims at reviewing the current understanding on nestmate/kin recognition in ants. This review consists of three parts. The first part concerns the diversity of recognition behaviors and their ecological implications with emphasis on nestmatelkin recognition; in the second part, the current understandings on the mechanism of nestmatelkin recognition are outlined; and in the third part, we discuss the ontogenetic development of nestmate recognition behavior and naturally mixed colonies. The study of the integration mechanism of social parasite may provide heuristic clues to the understanding of kin/nestmate recognition system. 相似文献
Ant societies, like other complex animal societies, have developed a sophisticated communication system, in which recognition behaviors are frequently involved Recognition abilities allow individuals to orient and modulate their behaviors effectively and appropriately in response to the characteristics andlor signals expressed by other organisms. Among recognition behaviors, nestmate recognition and kin recognition mechanisms have attracted great attention of sociobiologists, ecologists, insect physiologists and biochemists since 1970's. This is parallel with the popularization of Hamilton's kin selection theory. The present paper aims at reviewing the current understanding on nestmate/kin recognition in ants. This review consists of three parts. The first part concerns the diversity of recognition behaviors and their ecological implications with emphasis on nestmatelkin recognition; in the second part, the current understandings on the mechanism of nestmatelkin recognition are outlined; and in the third part, we discuss the ontogenetic development of nestmate recognition behavior and naturally mixed colonies. The study of the integration mechanism of social parasite may provide heuristic clues to the understanding of kin/nestmate recognition system. 相似文献
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毛角隐翅虫属(Trichophya Mannerheim 1830)系毛角隐翅虫亚科(TrichophyinaeGanglb.1895)的单一属。模式种为Trichophya pilicornis Gyllenhal。根据触角着生在眼的前方,11节,第1、2节很膨大,第3节以后细长如线,各节环生长毛;鞘翅缘折无与背面分隔的脊;跗节5节;腹后部渐尖等属征,不难与别的隐翅虫属区分。该属为一小属,全世界已知10种,T.pilicornis Gyll.分布全北区及东洋区;T.lativentris Casey, T.tars- 相似文献
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我们曾观察到消炎痛预处理能明显减轻四氯化碳和半乳糖胺对大鼠的肝损伤作用,本工作采用原代培养的大鼠肝细胞进一步观察了这一现象。结果表明,经消炎痛整体处理后分离的大鼠肝细胞,在原代培养的条件下,对四氯化碳的损伤仍然具有明显的抵抗作用,表现为细胞内酶的漏出少于对照组。正常大鼠离体肝细胞在原代培养条件下用消炎痛处理,在相当大的剂量和相当长的时间范围内未出现明显的抗损伤作用。结果提示:消炎痛整体处理可使肝细胞本身获得抗损伤的能力,而这种抗损伤能力的产生可能有赖于肝细胞外其它因素的参与。 相似文献
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拟毛突摇蚊属Paratrichocladius Santos Abreu 1918隶属于直突摇蚊亚科Ortho-cladinae,迄今全世界已知十余种。Hirvenoja(1973)对本属进行了整理。本文的记载为此属在我国的首次记录。 属征:复眼小眼面间密生细毛,触角比(AR)通常大于1;翅无大毛,腋瓣是多数缘毛;肩陷中等大小,背中鬃多数;无肛尖,抱器基节具一明显的上内突。 本文记述了采自吉林、四川省的2个新种和1个新纪录种。模式标本存南开大学生物学系。 相似文献