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Aromatic basmati rice is vulnerable to bacterial blight disease. Genes conferring resistance to bacterial blight have been identified in coarse rice; however, their incorporation into basmati varieties compromises the prized basmati aroma. We identified bacterial blight resistance genes Xa4, xa5, Xa7, and xa13 in 52 basmati landraces and five basmati cultivars using PCR markers. The Xa7 gene was found to be the most prevalent among the cultivars and landraces. The cultivars Basmati-385 and Basmati-2000 also contained the Xa4 gene; however, xa5 and xa13 were confined to landraces only. Ten landraces were found to have multiple resistance genes. Landraces Basmati-106, Basmati-189 and Basmati-208 contained Xa4 and Xa7 genes. Whereas, landraces Basmati-122, Basmati-427, Basmati-433 were observed to have xa5 and Xa7 genes. Landraces Basmati-48, Basmati-51A, Basmati-334, and Basmati-370A possessed Xa7 and xa13 genes. The use of landraces containing recessive genes xa5 and xa13 as donor parents in hybridization with cultivars Basmati-385 and Basmati-2000, which contain the genes Xa4 and Xa7, will expedite efforts to develop bacterial blight-resistant basmati rice cultivars through marker assisted selection, based on a pyramiding approach, without compromising aroma and grain quality.  相似文献   
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Inhaled ultrafine (nano) particles can translocate into the bloodstream and interact with circulatory cells causing systemic and cardiovascular events. To gain more insight into this potential mechanism, we studied the interaction of diesel exhaust particles (DEP) with human, rat and mouse erythrocytes in vitro. Incubation of erythrocytes with DEP (1, 10 or 100 μg/ml) for 30 min caused the highest hemolytic effect (up to 38%) in rats, compared to small but significant hemolysis in mice (up to 2.5%) and humans (up to 0.7%). Transmission electron microscopy of erythrocytes revealed the presence of variable degrees of ultrafine (nano)-sized aggregates of DEP either internalized and/or adsorbed onto the erythrocytes in the three species. A significant amount of DEP was found in rat and mouse (but not human) erythrocytes. Lipid erythrocyte susceptibility to in vitro peroxidation measured by malondialdehyde showed a significant and dose-dependent increase in erythrocytes of rats, but not humans or mice. Unlike in human erythrocytes, total antioxidant status (TAS) and superoxide dismutase (SOD) activity in rats were significantly and dose- dependently decreased. In mouse erythrocytes, DEP caused a decreased in SOD (at 10 μg/ml) and TAS (at 100 μg/ml) activities. In conclusion, DEP caused species-dependent erythrocyte hemolysis and oxidative stress, and were either taken up and/or adsorbed onto the red blood cells. Rat (and to a lesser degree mouse) erythrocytes were susceptible to DEP. Human erythrocytes showed the highest resistance to the observed effects. These species difference should be noted when using rats and mice blood as models for humans.  相似文献   
224.
Fungi are among the most important aeroallergens. The aim of this study was to provide aeromycological baseline information about Zarqa area, Jordan, for the first time. During the entire survey and from 170 settle plate exposures, a total of 735 mould- and 274 yeast colony-forming units (CFU) were collected. mould colonies were assigned to 35 genera and 59 species. The highest abundance was attributed to Cladosporium with a percentage of 29.1% of the total colony count followed by Fusarium 20%, Alternaria 7.7%, Ulocladium 6.5% Penicillium 4.2% and then Aspergillus 3.6%. Cladosporium showed one peak in October while Aspergillus and Penicillium peaked in September. Fusarium peaked in May and August and Alternaria in March and July. However, Ulocladium showed almost the same abundance from March to June and then in September and December. A double peak in total colony count and fungal diversity was found, the first was in March and the second in November–December. Significant differences of total fungal colony counts favouring the 1500 hours collection time over that at 1000 hours were found between November and January while no such significant differences were obtained between February and April. Our results also indicated differences in species composition between the two periods in different months. Spores of the three abundant species, Cladosporium, Fusarium and Alternaria, might favour high release in the 1500 hours period during winter while having a similar incidence during the two periods in the spring months.  相似文献   
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Background

Some observational studies have suggested that higher prenatal Vitamin D intake may be associated with improved health outcomes in childhood. However there have been mixed results in this area with some negative studies, especially for effects on atopic and respiratory outcomes. We examined the effect of prenatal Vitamin D on healthcare utilisation in the first three years of life.

Methods

In an ethnically stratified randomised controlled trial conducted at St Mary’s Hospital London, 180 women at 27 weeks gestation were allocated to no Vitamin D, 800 IU ergocalciferol daily until delivery, or a single oral bolus of 200,000 IU cholecalciferol. Participants were randomised in blocks of 15 using computer-generated numbers and investigators were blinded to group assignment. Supplementation increased maternal and cord blood 25(OH) vitamin D concentrations, but levels remained lower than current recommendations. Primary health economic outcome was overall cost of unscheduled healthcare utilisation in the first three years of life as documented in the child’s electronic health record. Secondary outcomes included cost attributable to: primary and secondary healthcare visits, respiratory and atopic complaints, cost in years 1, 2 and 3 of life and cost and frequency of prescribed medication. All costs were calculated as pounds sterling. Differences between groups were analysed using unpaired t-test or Mann-Whitney U test, and analysis of variance for adjusted analyses.

Results

We assessed 99/180 (55%) complete electronic health records, control (n = 31), daily (n = 36) and bolus (n = 32). We found no difference in total healthcare utilisation costs between the control and daily (mean difference in costs in pounds sterling 1.02, 95%CI -1.60, 1.65; adjusted 1.07, 95%CI -1.62, 1.86) or control and bolus groups (mean difference -1.58, 95%CI -2.63, 1.06; adjusted –1.40, 95%CI -2.45, 1.24). There were no adverse effects of supplementation reported during the trial.

Conclusions

We found no evidence that prenatal vitamin D supplementation from 27 weeks gestation to delivery, at doses which failed to completely correct maternal vitamin D deficiency, influence overall healthcare utilisation in children in the first 3 years.

Trial Registration

Controlled-Trials.com ISRCTN68645785  相似文献   
227.
Deferiprone is used as a chelation agent in chronic iron overload in β-thalassemia patients. Patients on deferiprone therapy show variable response to this drug in terms of reduction in iron overload as well as adverse drug reactions (ADRs). The pharmacogenetic studies on deferiprone have not carried out in patients with blood disorders in India. Therefore, the present study was carried out to evaluate the three most common nonsynonymous UGT1A6 polymorphisms Thr181Ala (541 A/G), Arg184Ser (552 A/C) and Ser7Ala (19 T/G) and therapeutic response to deferiprone in β-thalassemia major patients. Two hundred and eighty six (286) β-thalassemia major patients were involved in the study. Serum ferritin levels were estimated periodically to assess the status of the iron overload and the patients were grouped into responders and non-responders depending on the ferritin levels. The UGT1A6*2 polymorphisms were detected by PCR-RFLP methods. The association between the genotypes and outcome as well as ADRs was evaluated by Open EPI software. A significant difference was observed in the genotypic distribution of UGT1A6*2 Thr181Ala polymorphism in responders and non-responders. However, there was no difference in the genotypic distribution between patients with and without ADRs. As far as the UGT1A6*2 Arg184Ser polymorphism is concerned, no significant difference was observed between responders and non-responders. Further, evaluating the association of UGT1A6*2 Ser7Ala polymorphism with drug response, there was no significant difference in the genotypic distribution between responders and non-responders. However, there was a significant difference between responders with and without ADRs and non-responders with and without ADRs. In addition to this haplotype analysis was also carried out. However, we did not find any specific haplotype to be significantly associated with the deferiprone response in β-thalassemia major patients.  相似文献   
228.
Bone morphogenic protein (BMP)-7 is a member of the BMP family which are structurally and functionally related, and part of the TGFβ super family of growth factors. BMP-7 has been reported to inhibit renal fibrosis and TGFβ1-induced epithelial-mesenchymal transition (EMT), in part through negative interactions with TGFβ1 induced Smad 2/3 activation. We utilized in vivo bleomycin-induced fibrosis models in the skin and lung to determine the potential therapeutic effect of BMP-7. We then determined the effect of BMP-7 on TGFβ1-induced EMT in lung epithelial cells and collagen production by human lung fibroblasts. We show that BMP-7 did not affect bleomycin-induced fibrosis in either the lung or skin in vivo; had no effect on expression of pro-fibrotic genes by human lung fibroblasts, either at rest or following exposure to TGFβ1; and did not modulate TGFβ1 -induced EMT in human lung epithelial cells. Taken together our data indicates that BMP-7 has no anti-fibrotic effect in lung or skin fibrosis either in vivo or in vitro. This suggests that the therapeutic options for BMP-7 may be confined to the renal compartment.  相似文献   
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Hepatitis C is one of the common types of chronic liver disease, and its plausible association with trace metal imbalance has been investigated in the present study. The blood samples of hepatitis C patients and healthy donors were analysed for trace metals (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, and Zn) by flame atomic absorption spectrophotometry after wet acid digestion. In the blood of the hepatitis patients, mean concentrations of essential metals, Na, K, Fe, Ca, Mg, and Zn, were 918.7, 361.0, 102.5, 20.00, 24.66, and 9.429 ppm, respectively, while the mean metal levels in the blood of healthy donors were 1509, 406.8, 232.5, 28.35, 24.59, and 8.799 ppm, respectively. On the average, Cr was significantly higher, while Na, Fe, Ca, Cu, Mn, Pb, and Cd were comparatively lower in the blood of the patients. The correlation study manifested significantly divergent mutual relationships of trace metals in the blood of the patients and healthy donors. Multivariate statistical methods revealed considerably diverse distribution of trace metals in the two groups. Dissimilarity in the trace metal distribution was also noted with the gender and residential location of the donors in both groups.  相似文献   
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