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Background
The species-specificity of male genitalia has been well documented in many insect groups and sexual selection has been proposed as the evolutionary force driving the often rapid, morphological divergence. The internal female genitalia, in sharp contrast, remain poorly studied. Here, we present the first comparative study of the internal reproductive system of Sepsidae. We test the species-specificity of the female genitalia by comparing recently diverged sister taxa. We also compare the rate of change in female morphological characters with the rate of fast-evolving, molecular and behavioral characters. 相似文献84.
Adhesion and cytotoxicity of Bacillus cereus and Bacillus thuringiensis to epithelial cells are FlhA and PlcR dependent, respectively 总被引:1,自引:0,他引:1
Some bacteria of the Bacillus cereus group are enteropathogens. The first cells encountered by bacteria following oral contamination of the host are epithelial cells. We studied the capacity of these bacteria to adhere to epithelial cells and the consequences of this interaction. We found that cell adhesion is strain dependent and that a strain mutated in flhA, which encodes a component of flagellum-apparatus formation, is impaired in adhesion, suggesting that flagella are important virulence factors. The bacteria are cytotoxic to epithelial cells and induce substantial cytoplasmic and membrane alterations. However, direct contact between cells and bacteria is not required for cytotoxicity. The determinants of this cytotoxicity are secreted and their expression depends on the pleiotropic regulator PlcR. Adhesion and cytotoxicity of B. cereus to epithelial cells might explain the diarrhea caused by these pathogens. Our findings provide further insight into the pathogenicity of B. cereus group members. 相似文献
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Nalini Eswaran Sriram Parameswaran Balaji Sathram Bhagyam Anantharaman Raja Krishna Kumar G Sudhakar Johnson Tangirala 《BMC biotechnology》2010,10(1):23
Background
Environmentally inflicted stresses such as salinity and drought limit the plant productivity both in natural and agricultural system. Increasing emphasis has been directed to molecular breeding strategies to enhance the intrinsic ability of plant to survive stress conditions. Functional screens in microorganisms with heterologous genes are a rapid, effective and powerful tool to identify stress tolerant genes in plants. Jatropha curcas (Physic nut) has been identified as a potential source of biodiesel plant. In order to improve its productivity under stress conditions to benefit commercial plantations, we initiated prospecting of novel genes expressed during stress in J. curcas that can be utilized to enhance stress tolerance ability of plant. 相似文献86.
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Nalini Yasoda Hirimuthugoda Adeniyi C. Adeola Patthamesthrige Wimal Anthony Perera Xing Chen Weligalle Wedarallage Dewar Asoka Gunawardena Humpita Gamaralalage Thilini Nisanka Gunawardana Ting‐Ting Yin Ming‐Shan Wang Gui‐Mei Li Zhao‐Li Ding Wen‐Zhi Wang Hai‐Bing Xie Min‐Sheng Peng Ya‐Ping Zhang 《Animal genetics》2017,48(5):622-623
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OBJECTIVE: To analyze neutrophilic phagocytosis by tumor cells in fine needle aspirate (FNA) smears from different types of tumor. STUDY DESIGN: A retrospective review of a total of 7 cases showing prominent neutrophilic phagocytosis by tumor cells in FNA smears during the period July 2003-December 2004. RESULTS: This feature was seen in malignant fibrous histiocytoma and poorly differentiated renal cell carcinoma in addition to giant cell carcinoma of the lung. CONCLUSION: Neutrophilic phagocytosis by tumor cells is seen in FNA smears and on cytomorphology. The differential diagnoses should include both pleomorphic sarcomas and carcinomas. 相似文献
90.
Cooke MS Mistry N Ahmad J Waller H Langford L Bevan RJ Evans MD Jones GD Herbert KE Griffiths HR Lunec J 《Free radical biology & medicine》2003,34(2):218-225
Oxidative DNA damage is postulated to be involved in carcinogenesis, and as a consequence, dietary antioxidants have received much interest. A recent report indicates that vitamin C facilitates the decomposition of hydroperoxides in vitro, generating reactive aldehydes. We present evidence for the in vivo generation of glyoxal, an established product of lipid peroxidation, glucose/ascorbate autoxidation, or free radical attack of deoxyribose, following supplementation of volunteers with 400 mg/d vitamin C. Utilizing a monoclonal antibody to a deoxycytidine-glyoxal adduct (gdC), we measured DNA lesion levels in peripheral blood mononuclear cells. Supplementation resulted in significant (p =.001) increases in gdC levels at weeks 11, 16, and 21, with corresponding increases in plasma malondialdehyde levels and, coupled with previous findings, is strongly suggestive of a pro-oxidative effect. However, continued supplementation revealed a highly significant (p =.0001) reduction in gdC levels. Simultaneous analysis of cyclobutane thymine dimers revealed no increase upon supplementation but, as with gdC, levels decreased. Although no single mechanism is identified, our data demonstrate a pro-oxidant event in the generation of reactive aldehydes following vitamin C supplementation in vivo. These results are also consistent with our hypothesis for a role of vitamin C in an adaptive/repair response and indicate that nucleotide excision repair specifically may be affected. 相似文献