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101.
102.
Rice is the staple food for more than fifty percent of the world's population, and is therefore an important crop. However, its production is hindered by several biotic and abiotic stresses. Although rice is the only crop that can germinate even in the complete absence of oxygen (i.e. anoxia), flooding (low oxygen) is one of the major causes of reduced rice production. Rice germination under anoxia is characterized by the elongation of the coleoptile, but leaf growth is hampered. In this work, a comparative proteomic approach was used to detect and identify differentially expressed proteins in the anoxic rice coleoptile compared to the aerobic coleoptile. Thirty-one spots were successfully identified by MALDI-TOF MS analysis. The majority of the identified proteins were related to stress responses and redox metabolism. The expression levels of twenty-three proteins and their respective mRNAs were analyzed in a time course experiment.  相似文献   
103.
Cardiovascular disorders and coronary artery disease (CAD) are significant contributors to morbidity and mortality in heart patients. As genes of the folate/homocysteine pathway have been linked with the vascular disease, we investigated association of these gene polymorphisms with CAD/myocardial infarction (MI) using the novel approach of tetraprimer ARMS-PCR. A total of 230 participants (129 MI cases, 101 normal subjects) were recruited. We genotyped rs1801133 and rs1801131 SNPs in 5'10' methylenetetrahydrofolate reductase (MTHFR), rs1805087 SNP in 5' methyltetrahydrofolate homocysteine methyltransferase (MTR), rs662 SNP in paroxanse1 (PON1), and rs5742905 polymorphism in cystathionine beta synthase (CBS). Angiotensin converting enzyme (ACE) insertion/deletion polymorphism was detected through conventional PCR. Covariates included blood pressure, fasting blood sugar, serum cholesterol, and creatinine concentrations. Our results showed allele frequencies at rs1801133, rs1801131, rs1805087 and the ACE insertion/deletion (I/D) polymorphism varied between cases and controls. Logistic regression, after adjusting for covariates, demonstrated significant associations of rs1801133 and rs1805087 with CAD in the additive, dominant, and genotype model. In contrast, ACE I/D polymorphism was significantly related with CAD where recessive model was applied. Gene-gene interaction against the disease status revealed two polymorphism groups: rs1801133, rs662, and rs1805087; and rs1801131, rs662, and ACE I/D. Only the latter interaction maintained significance after adjusted for covariates. Our study concludes that folate pathway variants exert contributory influence on susceptibility to CAD. We further suggest that tetraprimer ARMS-PCR successfully resolves the genotypes in selected samples and might prove to be a superior technique compared to the conventional approach.  相似文献   
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This review focuses on the potential role that oxidative stress plays in the adverse effects of PM(10). The central hypothesis is that the ability of PM(10) to cause oxidative stress underlies the association between increased exposure to PM(10) and both exacerbations of lung disease and lung cancer. Pulmonary inflammation may also underlie the cardiovascular effects seen following increased PM(10), although the mechanisms of the cardiovascular effects of PM(10) are not well understood. PM(10) is a complex mix of various particle types and several of the components of PM(10) are likely to be involved in the induction of oxidative stress. The most likely of these are transition metals, ultrafine particle surfaces, and organic compounds. In support of this hypothesis, oxidative stress arising from PM(10) has been shown to activate a number of redox-responsive signaling pathways in lung target cells. These pathways are involved in expression of genes that play a role in responses relevant to inflammation and pathological change, including MAPKs, NF-kappaB, AP-1, and histone acetylation. Oxidative stress from particles is also likely to play an important role in the carcinogenic effects associated with PM(10) and hydroxyl radicals from PM(10) cause DNA damage in vitro.  相似文献   
106.
Peptic ulcer disease is a gastrointestinal disorder defined by mucosal damage and free oxygen radicals associated with peptic ulcer and gastritis. Cinnamon is a traditional herb used for many diseases and it has also effects as an antioxidant, anti-inflammatory, antispasmodic and anti-ulcerative. Our research is based on oxidative stress and effects of Oleum cinnamomi on stomach, liver and kidney disorders induced by ethanol. In our experiment, 2–3 month old male Sprague–Dawley rats were used. One hour before the mucosal damage induced by 70 % ethanol, O. cinnamomi (2.5 ml/kg) was added into the groups. Gastric pH, analysis of gastric mucus and ulcer index were calculated from samples obtained from the stomach. Superoxide dismutase (SOD), malondialdehyde and catalase (CAT) levels were determined in stomach, liver and kidney homogenates and erythrocyte hemolysate. Histopathological examination of stomach, liver and kidney were determined with H&E staining. The non-treated ulcerative group showed higher scores than the control group which was treated with O. cinnamomi, when ulcer scores, gastric mucus and pH level of stomach are compared. Increased lipid peroxidation levels were observed in the liver, kidney and erythrocyte hemolysate. SOD activity was decreased in liver whereas increased in stomach of ethanol treated ulcerative groups. CAT levels were increased in stomach and liver of ethanol treated rats. Histopathological findings showed that ethanol treatment cause multiply organ damage such as stomach, liver and kidney injury. O. cinnamomi treatment protected these tissues from ethanol-induced damage. Consequently, the current investigation shows that O. cinnamomi has protective effects on ethanol-induced oxidative and mucosal damage.  相似文献   
107.
The electronic circular dichroism (ECD) spectra of two sesquiterpenoids ( 1 and 2 ) related to oplopanone, obtained from a methanolic extract of the plant Serphidium stenocephalum (Artemisia stenocephala), were measured and reproduced by means of time‐dependent density functional theory (TDDFT) calculations, establishing their absolute configuration. The application of ketone octant rule for carbonyl n‐π* ECD band to compounds 1 and 2 , which include an acyclic carbonyl group, was critically assessed. The peculiar oplopanone skeleton makes a straightforward application of the octant rule impossible, because of the uncertainty related to the shape of the so‐called third nodal surface separating front and back octants. The various group contributions to the carbonyl n‐π* ECD band were estimated with TDDFT calculations on selected molecular models obtained by consecutive dissections from 1 . Chirality 26:39–43, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
108.
Increasing contamination and higher enrichment ratio of non-essential heavy metal cadmium (Cd) induce various toxic responses in plants when accumulated above the threshold level. These effects and growth responses are genotype and Cd level dependent. An experiment was conducted to analyze the effect of Cd toxicity in Brassica juncea [L] Czern and Coss by selecting its two varieties Varuna and RH-30. Cadmium (0, 25, 50 or 100 mg CdCl2 kg−1 of soil) fed to soil decreased the values of growth characteristics, activity of nitrate reductase and leaf water potential, whereas activities of antioxidant enzymes and proline content increased with the increasing concentration of Cd, observed at 30 and 60 day stages of growth, in both the varieties. Moreover, Cd uptake by the roots was higher in RH-30 than Varuna. Also the activity of antioxidant enzymes and proline accumulation were higher in Varuna with increasing soil level of Cd. Out of the two varieties, Varuna was more tolerant than RH-30 to Cd stress.  相似文献   
109.
A new species, Goffartia phalacra n. sp. is described and illustrated. The body is thin and slender with L = 511 to 646 μm; a = 37.1 to 47.4; b = 4.8 to 6; c = 2.6 to 4.8; c′ = 13.6 to 32.8; V = 40% to 49% in females. Males are smaller but similar to females and the posterior region is strongly curved. The species is characterized by a tubular stoma, a smooth round lip region, anterior pharynx much smaller than posterior pharynx, two pairs of unicellular glands associated with the vagina, and males with a broad keel-shaped gubernaculum. G. phalacra n. sp. can be differentiated from all other species of the genus by its lip region and the structure of the gubernaculum. This is the first instance of a species of Goffartia occurring in a terrestrial habitat and the first report of a species from India.  相似文献   
110.
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