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31.
During pathogen attack, the host plant induces genes to ward off the pathogen while the pathogen often produces effector proteins to increase susceptibility of the host. Gene expression studies of syncytia formed in soybean root by soybean cyst nematode (Heterodera glycines) identified many genes altered in expression in resistant and susceptible roots. However, it is difficult to assess the role and impact of these genes on resistance using gene expression patterns alone. We selected 100 soybean genes from published microarray studies and individually overexpressed them in soybean roots to determine their impact on cyst nematode development. Nine genes reduced the number of mature females by more than 50 % when overexpressed, including genes encoding ascorbate peroxidase, β-1,4-endoglucanase, short chain dehydrogenase, lipase, DREPP membrane protein, calmodulin, and three proteins of unknown function. One gene encoding a serine hydroxymethyltransferase decreased the number of mature cyst nematode females by 45 % and is located at the Rhg4 locus. Four genes increased the number of mature cyst nematode females by more than 200 %, while thirteen others increased the number of mature cyst nematode females by more than 150 %. Our data support a role for auxin and ethylene in susceptibility of soybean to cyst nematodes. These studies highlight the contrasting gene sets induced by host and nematode during infection and provide new insights into the interactions between host and pathogen at the molecular level. Overexpression of some of these genes result in a greater decrease in the number of cysts formed than recognized soybean cyst nematode resistance loci.  相似文献   
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Neurochemical Research - Epilepsy comes after stroke as the most common chronic neurological disorder worldwide. Inflammation enhances neuronal hyperexcitability that could provide a background...  相似文献   
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Generalized vitiligo is an autoimmune disorder characterized by acquired white patches of skin and overlying hair, the result of loss of melanocytes from involved areas. The most common disorder of pigmentation, vitiligo occurs with a frequency of 0.1-2.0% in various populations. Family clustering of cases is not uncommon, in a non-Mendelian pattern suggestive of multifactorial, polygenic inheritance. We surveyed 2624 vitiligo probands from North America and the UK regarding clinical characteristics, familial involvement, and association with other autoimmune disorders, the largest such survey ever performed. More than 83% of probands were Caucasians, and the frequency of vitiligo appeared approximately equal in males and females. The frequency of vitiligo in probands' siblings was 6.1%, about 18 times the population frequency, suggesting a major genetic component in disease pathogenesis. Nevertheless, the concordance of vitiligo in monozygotic twins was only 23%, indicating that a non-genetic component also plays an important role. Probands with earlier disease onset tended to have more relatives affected with vitiligo, suggesting a greater genetic component in early onset families. The frequencies of six autoimmune disorders were significantly elevated in vitiligo probands and their first-degree relatives: vitiligo itself, autoimmune thyroid disease (particularly hypothyroidism), pernicious anaemia, Addison's disease, systemic lupus erythematosus, and probably inflammatory bowel disease. These associations indicate that vitiligo shares common genetic aetiologic links with these other autoimmune disorders. These results suggest that genomic analysis of families with generalized vitiligo and this specific constellation of associated autoimmune disorders will be important to identify the mechanisms of genetic susceptibility to autoimmunity.  相似文献   
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The use of metals in medicine has grown in popularity in clinical and commercial settings. In this study, the immune-protecting effects and the hypoglycemic and antioxidant activity of vanadyl sulfate (VOSO4) and/or selenium tetrachloride (Se) on oxidative injury, DNA damage, insulin resistance, and hyperglycemia were assessed. Fifty male albino rats were divided into five groups, and all treatments were administrated at 9:00 a.m. daily for 60 successive days: control, STZ (Streptozotocin; 50 mg/kg of STZ was given to 6 h fasted animals in a single dose, followed by confirmation of diabetic state occurrence after 72 h by blood glucose estimation at >280 mg/dl), STZ (Diabetic) plus administration of VOSO4 (15 mg/kg) for 60 days, STZ (Diabetic) plus administration of selenium tetrachloride (0.87 mg/Kg), and STZ plus VOSO4 and, after 1/2 h, administration of selenium tetrachloride at the above doses. The test subjects’ blood glucose, insulin hormone, HbA1C, C-peptide, antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, myeloperoxidase, and xanthine oxidase), markers of lipid peroxidation (MDA), and histological sections of pancreatic tissues were evaluated, and a comet assay was performed. Histological sections in pancreas tissues were treated as indicators of both VOSO4 and selenium tetrachloride efficacy, either alone or combined, for the alleviation of STZ toxicity. The genotoxicity of diabetes mellitus was assessed, and the possible therapeutic roles of VOSO4 or selenium tetrachloride, or both, on antioxidant enzymes were studied. The findings show that the administration of VOSO4 with selenium tetrachloride reduced oxidative stress to normal levels, lowered blood glucose levels, and elevated insulin hormone. Additionally, VOSO4 with selenium tetrachloride had a synergistic effect and significantly decreased pancreatic genotoxicity. The data clearly show that both VOSO4 and selenium tetrachloride inhibit pancreatic and DNA injury and improve the oxidative state in male rats, suggesting that the use of VOSO4 with selenium tetrachloride is a promising synergistic potential ameliorative agent in the diabetic animal model.  相似文献   
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Mycobacterium vaccae is a rapidly growing, nontuberculous Mycobacterium species that is generally not considered a human pathogen and is of major pharmaceutical interest as an immunotherapeutic agent. We report here the annotated genome sequence of the M. vaccae type strain, ATCC 25954.  相似文献   
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The present work aims at studying the effect of gamma radiation on the hard dental tissues. Eighty adult male albino rats with weights of about 250 g were used. The rats were irradiated at 0.2, 0.5, 1.0, 2.0, 4.0 and 6.0 Gy whole-body gamma doses. The effects on hard dental tissue samples were investigated after 48 h in histological and ground sections using light microscopy. Areas of acid phosphatase activity were detected using tartrate-resistant acid phosphatase (TRAP) stains. Observation of histological sections revealed disturbance in predentin thickness and odontoblastic layer as the irradiation dose increased. In cementum, widened cementocytes lacunae were occasionally detected even with low irradiated doses. On the other hand, relatively homogenous enamel was detected with darkened areas in enamel surface at doses over than 0.5 Gy. TRAP-positive cells were detected on the surface of the dentin of irradiated groups as well as cementum surface. Minimal detectable changes were observed in ground sections.  相似文献   
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Plant Molecular Biology Reporter - Saint Katherine Protectorate (SKP) hosts 24% of Egyptian Silene species including the endemic ones. This study investigated five Silene species representing 17%...  相似文献   
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Forty-day-old Atriplex halimus seedlings were treated with either NaCl (50, 300 and 550?mM) for the subsequent 30?days or PEG for the following 3, 6 and 10?days. Shoot fresh and dry weights were significantly increased by 50?mM NaCl; nevertheless, the other concentrations had no effect. However, the growth was reduced by drought only after 10?days. Meanwhile, Na+ was accumulated in treated plants; the magnitude of accumulation was highest with high NaCl concentration or PEG for 10?days. The metabolite profiles showed discrimination particularly up-regulation of the amino acids proline, valine, isoleucine, and methionine. Moreover, the macro analysis revealed that NaCl- and PEG-treated plants shared 10?% of the metabolites in the positive mode, however, 87?% were unique to NaCl and 46?% were unique to PEG whereas in the negative mode, 8?% were in share while 90 or 53?% were restricted to NaCl or PEG, respectively. Additionally, sucrose in particular was significantly increased up to threefold and fivefold by 300 and 550?mM NaCl, respectively and up to 2.5-fold by drought for 10?days, nevertheless, the other sugar fractions remained largely unchanged. Also, proline was significantly increased by only the high NaCl concentrations and the long-term drought, nonetheless, the other treatments led, if any, to decreases. These results conclude that NaCl affects the metabolite profiles more than PEG and these metabolites might contribute to osmotic adjustments to act as osmoprotectants rather than osmolytes. These changes of metabolomics might function in many resistance and stress responses.  相似文献   
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