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981.
In this study we have tested the effects of d-propranolol (D-Pro) on the iron uptake, iron release and oxidative response of iron-loaded cells in a cellular model of iron-overload using isolated rat peritoneal macrophages incubated with iron-dextran (Fe-D). Pretreatment of macrophages with D-Pro (5–200 μ M) prior to Fe-D exposure decreased the cellular iron content and partially prevented iron release from latex-activated macrophages. Release of reactive oxygen species from activated cells was detected by dichlorodihydrofluorescein (DCDHF, 5 μ M) oxidation. We found that loading cells with Fe-D increased their response to latex, which was prevented by the lysosomotropic antioxidant agent D-Pro (10 μ M).  相似文献   
982.
One new xanthone, caroxanthone (1) together with six known xanthones, 4-prenyl-2-(3,7-dimethyl-2,6-octadienyl)-1,3,5,8-tetrahydroxyxanthone (2), smeathxanthone A (3), gartanin (4), euxanthone (5), 8-hydroxycudraxanthone G (6) and morusignin I (7) were isolated from the stem bark of Garcinia nobilis. The structures were determined by 1D- and 2D-NMR techniques. All these compounds were tested for anti-glycation, α-glucosidase and α-chymotrypsin activities. Some of them exhibited strong to moderate α-glucosidase activities, while none of them inhibited α-chymotrypsin. Compounds 6 and 7 were found to be modest α-glucosidase inhibitors with IC50 values of 76 μM and 84 μM, respectively.  相似文献   
983.
Among a total of 27 cultivable salt tolerant endophytic bacteria isolated from Catharanthus roseus grown in highly salt affected coastal region of cuddalore district, Tamilnadu, India four isolates were found to be positive for nitrogenase activity. The isolates were evaluated for their stress tolerance efficiency and screened for different PGP traits. Based on the above studied parameters, and ability to produce 1-aminocyclopropane-1-carboxylate (ACC) deaminase (4.24???mol ??-ketobutyrate mg_1 protein h_1) the salt tolerant diazotrophic isolate AUM54 was selected for further investigation and identified as Achromobacter xylosoxidans by 16S rRNA gene sequencing. The ability of this isolate to ameliorate salt stress in C. roseus was evaluated under gnotobiotic and pot culture conditions. At 150?mM NaCl level A. xylosoxidans AUM54 treated plants recorded ethylene level of 394.1 p mol ethylene g?1 FW h?1 compared to the ethylene level of 516.0 p mol ethylene g?1 FW h?1 recorded in the un inoculated control. A. xylosoxidans AUM54 inoculated plants recorded the maximum germination percentage of 98.3, vigor index of 2231.4, plant height of 120.4?cm, root dry weight of 53.24?g Plant_1 and ajmalicine content of 1.60?mg?g?1, compared to the germination percentage of 91.6%, vigour index of 1511.5, plant height of 105.8, root weight of 47.2?g Plant?1, and ajmalicine content of 1.23?mg?g?1 in uninoculated plants grown without NaCl treatment. This isolate also decreased plant ethylene levels by 11?C23% and increased the antioxidative enzyme content of inoculated C. roseus plants to the tune of 19?C32% for ascorbate peroxidase (APX) activity, 20?C30% for superoxide dismutase (SOD) activity and 4?C16% for catalase (CAT) under normal and salt affected conditions.  相似文献   
984.
ABSTRACT: BACKGROUND: H. pylori infection has been associated with many micronutrient deficiencies. There is a dearth of data from communities with nutritional deficiencies and high prevalence of H. pylori infection. The aim of this study was to determine the impact of H. pylori infection on serum levels of vitamin B12, folate and homocysteine in patients with functional dyspepsia (FD). METHODS: One hundred and thirty-two patients with FD undergoing gastroscopy were enrolled. The serum was analyzed for B12, folate and homocysteine levels before gastroscopy. H. pylori infection was diagnosed by histopathological examination of gastric biopsies and urea breath test. An independent sample t-test and the Mann-Whitney test were used to compare mean serum concentrations of biomarkers between H. pylori-positive and H. pylori-negative groups of patients. A Chi-square test was performed to assess the differences among proportions, while Spearman's rho was used for correlation analysis between levels of B12 and homocysteine. RESULTS: The mean age of the group was 40.3 +/- 11.5 (19-72) years. Folate deficiency was seen in 43 (34.6%), B12 deficiency in 30 (23.1%) and hyperhomocysteinemia in 60 (46.2%) patients. H. pylori was present in 80 (61.5%) patients with FD while it was absent in 50 (38.5%). Mean serum levels of B12, folate and homocysteine in the H. pylori-positive group of patients were not significantly different from the levels in the H. pylori-negative group (357 +/- 170 vs. 313 +/- 136 pg/mL; p = 0.13), (4.35 +/- 1.89 vs. 4.42 +/- 1.93 ng/mL; p = 0.84); (15.88 +/- 8.97 vs. 16.62 +/- 7.82 mumol/L; p = 0.24); respectively. B12 deficiency ([less than or equal to]200 pg/mL) was 23.8% in the H. pylori-positive patients versus 22.0% in the H. pylori-negative patients. Folate deficiency ([less than or equal to]3.5 ng/mL) was 33.8% in the H. pylori-positive group versus 36% in the H. pylori-negative group. Hyperhomocysteinemia (>15 mumol/L) was present in 46.2% of H. pylori-positive patients compared to 44% in the H. pylori-negative group. Correlation analysis indicated that serum B12 levels were inversely associated with serum levels of homocysteine in patients with FD (rho = 0.192; p = 0.028). CONCLUSIONS: This study demonstrated an inverse relationship between serum levels of B12 and homocysteine in patients with FD. Moreover, no impact of the presence of H. pylori was found on B12, folate and homocysteine levels in such patients.  相似文献   
985.
Bovine pancreatic trypsin was crystallized, in-complex with Lima bean trypsin inhibitor (LBTI) (Phaseolus lunatus L.), in the form of a ternary complex. LBTI is a Bowman–Birk-type bifunctional serine protease inhibitor, which has two independent inhibitory loops. Both of the loops can inhibit trypsin, however, only the hydrophobic loop is specific for inhibiting chymotrypsin. The structure of trypsin incomplex with the LBTI has been solved and refined at 2.25 Å resolution, in the space group P41, with Rwork/Rfree values of 18.1/23.3. The two binding sites of LBTI differ in only two amino acids. Lysine and leucine are the key residues of the two different binding loops positioned at the P1, and involved in binding the S1 binding site of trypsin. The asymmetric unit cell contains two molecules of trypsin and one molecule of LBTI. The key interactions include hydrogen bonds between LBTI and active site residues of trypsin. The 3D structure of the enzyme–inhibitor complex provided details insight into the trypsin inhibition by LBTI. To the best of our knowledge, this is the first report on the structure of trypsin incomplex with LBTI.  相似文献   
986.
987.
This study investigated morphological and biochemical characteristics of CB9, CB10 and SR05 cotton varieties and observed their effect on feeding and growth of cotton armyworm Spodoptera litura. Morphological characters of plant architecture, branching, color, hairiness, trichome density and boll size indicated that CB9 is a bushy, well developed, branched, light bronze colored and hairy variety with number of trichomes 193/cm2 and boll weight 5.5–6.0 g/boll. Both CB9 and CB10 bear normal leaves and spherical bolls whereas SR05 has well‐ventilated branching, okra shaped and ventrally arranged light bronze colored leaves and oval bolls ranging 4.0–4.5 g/boll. Biochemical analysis indicated significant differences in starch and protein contents, which range 11.4–21.3 and 17.5–30.6%, respectively. The lowest percentages of starch and protein were found in SR05 and CB9, respectively. Cotton varieties showed significant effects on second, third, fourth and fifth instar larval weight and they attained the highest weights (22.7, 133.8, 168.2 and 1190.2 mg, respectively) when fed SR05. Larvae and moths fed SR05 also showed the significantly highest cocoon, exuviae, and adult male and female weights (434.5, 19.2, 161.3 and 232.4 mg, respectively). The cotton armyworm showed the significantly highest growth index (1.5) as well as lowest feeding index (0.05) on SR05. Results of this study indicated that SR05 is suitable for larval feeding and development, and suggest that this variety is least suitable for cotton growers in areas where S. litura is a major pest.  相似文献   
988.
The study was conducted on the cadmium (Cd) transfer from soil to pasture at Khizerabad Livestock Farm, District Sargodha (falling under semi-arid conditions), Pakistan. The concentrations of Cd in the soil and forage ranged from 2.80 to 6.74 mg/kg and 1.14 to 4.20 mg/kg, respectively, in different sampling periods. The higher values of Cd in pasture suggested the possible risk of entering Cd into higher food chain as these concentrations of Cd can potentially be transported from soil to different animals rearing on the farm pastures, and they should be taken into account in risk assessment of chemical toxicity. Providing region-specific mineral mixture having highly bioavailable forms of other trace elements to the ruminants like Zn, Fe, and Mn, which are known to antagonize Cd, would help in overcoming the Cd toxicity. There is an urgent need of permanent monitoring of cadmium content in the feed used in animal nutrition at livestock farm.  相似文献   
989.
Owing to recent findings of certain unusual sex steroid binding in liver disease--particularly an allosteric biphasic pattern (pattern A) unique to the serum of patients with hepatocellular carcinoma--the serum binding characteristics for 5 alpha-dihydrotestosterone were examined in serum samples from six patients with primary biliary cirrhosis who had developed hepatocellular carcinoma. In all serum samples taken after the development of tumour pattern A binding only was obtained, and in four cases in which earlier samples were also examined there was a transformation from the normal, non-specific binding pattern, or an allosteric plateau pattern seen in non-malignant liver disease (designated D and C respectively), to pattern A coincident with the rise in serum alpha fetoprotein. In one patient chemotherapy leading to a fall in alpha fetoprotein abolished pattern A binding, showing further its close association with tumour growth. The value of pattern A binding as a tumour marker in hepatocellular carcinoma warrants further study.  相似文献   
990.
The present study was conducted to investigate the cell wall properties in two wheat (Triticum aestivum L.) cultivars differing in their sensitivity to Al stress. Seedlings of Al-resistant, Inia66 and Al-sensitive, Kalyansona cultivars were grown in complete nutrient solutions for 4 days and then subjected to treatment solutions containing Al (0, 50 microM) in a 0.5 mM CaCl(2) solution at pH 4.5 for 24 h. Root elongation was inhibited greatly by the Al treatment in the Al-sensitive cultivar compared to the Al-resistant cultivar. The Al-resistant cultivar accumulated less amount of Al in the root apex than in the Al-sensitive cultivar. The contents of pectin and hemicellulose in roots were increased with Al stress, and this increase was more conspicuous in the Al-sensitive cultivar. The molecular mass of hemicellulosic polysaccharides was increased by the Al treatment in the Al-sensitive cultivar. The increase in the content of hemicellulose was attributed to increase in the contents of glucose, arabinose and xylose in neutral sugars. Aluminum treatment increased the contents of ferulic acid and p-coumaric acid especially in the Al-sensitive cultivar by increasing the activity of phenylalanine ammonia lyase (PAL, EC 4.3.1.5). Aluminum treatment markedly decreased the beta-glucanase activity in the Al-sensitive cultivar, but did not exert any effect in the Al-resistant cultivar. These results suggest that the modulation of the activity of beta-glucanase with Al stress may be involved in part in the alteration of the molecular mass of hemicellulosic polysaccharides in the Al-sensitive cultivar. The increase in the molecular mass of hemicellulosic polysaccharides and ferulic acid synthesis in the Al-sensitive cultivar with Al stress may induce the mechanical rigidity of the cell wall and inhibit the elongation of wheat roots.  相似文献   
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