Inhibitory Effects of Isolated Compounds from Black Coloured Rice Bran on the Complement Classical Pathway

The present study evaluated the anticomplement effects of isolated compounds from black coloured rice bran in the classical pathway of the complement system. Using column chromatography, three compounds: oryzafuran, quercetin and protocatechuic acid, were isolated and evaluated for in vitro anticomplement activity. Oryzafuran showed the most potent inhibitory activity against the complement system, with 50% inhibitory concentration (IC₅₀) values of 126.2 µg/mL. This is the first report of anticomplement activity of isolated compounds from black coloured rice bran. Copyright © 2011 John Wiley & Sons, Ltd.     

Parent-independent genotyping for constructing an ultrahigh-density linkage map based on population sequencing

Bar-coded multiplexed sequencing approaches based on new-generation sequencing technologies provide capacity to sequence a mapping population in a single sequencing run. However, such approaches usually generate low-coverage and error-prone sequences for each line in a population. Thus, it is a significant challenge to genotype individual lines in a population for linkage map construction based on low-coverage sequences without the availability of high-quality genotype data of the parental lines. In this paper, we report a method for constructing ultrahigh-density linkage maps composed of high-quality single-nucleotide polymorphisms (SNPs) based on low-coverage sequences of recombinant inbred lines. First, all potential SNPs were identified to obtain drafts of parental genotypes using a maximum parsimonious inference of recombination, making maximum use of SNP information found in the entire population. Second, high-quality SNPs were identified by filtering out low-quality ones by permutations involving resampling of windows of SNPs followed by Bayesian inference. Third, lines in the mapping population were genotyped using the high-quality SNPs assisted by a hidden Markov model. With 0.05× genome sequence per line, an ultrahigh-density linkage map composed of bins of high-quality SNPs using 238 recombinant inbred lines derived from a cross between two rice varieties was constructed. Using this map, a quantitative trait locus for grain width (GW5) was localized to its presumed genomic region in a bin of 200 kb, confirming the accuracy and quality of the map. This method is generally applicable in genetic map construction with low-coverage sequence data.     

Estimation of Benchmark Rice Cadmium Doses as Threshold Values for Abnormal Urinary Findings with Adjustment for Consumption of Jinzu River Water

We performed this study to determine whether both eating cadmium (Cd)-polluted rice and drinking and/or cooking with Jinzu River water are associated with renal tubular dysfunction. A multiple logistic regression analysis of retrospective data indicated that both factors may contribute to this condition. Estimated threshold values of rice Cd concentration in men were 0.13–0.27 ppm and 0.09–0.18 ppm in women, without adjustment for use of Jinzu River water. The additional influence of drinking and/or cooking with Jinzu River water was estimated to be about 0.008 ppm.     

我国菰米对高脂膳食大鼠血脂及炎性因子的影响

目的探讨菰米对高脂膳食诱导脂代谢紊乱大鼠血脂及炎性因子水平的调控作用。方法44只雄性SD大鼠随机分为阴性对照组、高脂模型组、米面组和菰米组;以相应饲料连续喂养8w,测定各组大鼠体重、血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)、高敏C反应蛋白(hs-CRP)等指标。结果与阴性对照组相比,高脂模型组和米面组大鼠的血清TC、TG显著上升,HDL-C显著降低;与高脂模型组和米面组比较,菰米组的血清TC、TG显著下降,HDL-C显著升高,TNF-α、hs-CRP显著下降。结论菰米具有降低脂代谢紊乱大鼠血脂的作用,并能改善高脂血症的低度炎性状态。     

Rice consumption and urinary concentrations of arsenic in US adults

Exposure to inorganic arsenic in the general population occurs mainly from drinking water and food sources. This study examined the association between rice consumption and urinary concentrations of arsenic in US adults, aged 20–85 years, in the 2003–2006 National Health and Nutrition Examination Survey. Significantly higher geometric means of creatinine-corrected urinary concentrations of total arsenic (TAs) and dimethylarsinic acid (DMA) were found in participants who consumed rice more than twice per week, compared to the reference group. Multivariate logistic regression analysis revealed a statistically significant association between rice consumption and urinary concentrations of TAs [odds ratio (OR) = 1.51 (1.08, 2.09)] and DMA [OR = 2.24 (1.57, 3.21)] after adjustment for demographic variables, seafood intake (the main source of organic arsenic), and source of drinking water. Furthermore, significant variations in rice consumption and urinary concentrations of arsenic were observed in different racial groups. This study demonstrated that rice consumption contributed to inorganic arsenic exposure in US adults.     

杂交稻种子贮藏技术及寿命预测研究

对水稻三系配套的雄性不育系、保持系、恢复系乃其杂交一代种子,在各种恒定的含水量和室温下贮存,测定其寿命变比。发现不育系和杂交一代种子的安全水分比保持系和恢复系的13％(国家标准对普通籼稻常规品种的最高限度)低2％;不育系和杂种一代种子水分在11％时、寿命变化最接近典型的反S形生存曲线,当发芽率降到80％左右时,生存曲线急速下降。根据典型生存曲线规律,拟配合新的寿命预测方程。     

山梨醇对籼稻愈伤组织培养的效应

以6个籼稻品种为供试材料,研究结果肯定了培养基中附加成分山梨醇在愈伤组织继代培养中,具有促进愈伤组织生长及提高其分化潜力的效果;籼稻亚种中的不同品种,愈伤组织的生长及再生植株能力,在继代培养的后期表现出明显的品种特异性;分化培养基中加入不同浓度配比激素,对诱导器官分化的效果有明显差别,激动素(KT)与萘乙酸(NAA)的比例为5:1有利于取得根、芽生长的同步性。     

Facilitation of Rice Stripe Virus Accumulation in the Insect Vector by Himetobi P Virus VP1

The small brown planthopper (SBPH) is the main vector for rice stripe virus (RSV), which causes serious rice stripe disease in East Asia. To characterize the virus-vector interactions, the SBPH cDNA library was screened with RSV ribonucleoprotein (RNP) as bait using a GAL4-based yeast two-hybrid system. The interaction between RSV-RNP and the Himetobi P virus (HiPV, an insect picorna-like virus) VP1 protein was identified. The relationships between HiPV and RSV in SBPH were further investigated, and the results showed that the titer of RSV was commonly higher in single insect that exhibited more VP1 expression. After the VP1 gene was repressed by RNA silencing, the accumulation of RSV decreased significantly in the insect, whereas the virus acquisition ability of SBPH was unaffected, which suggests that HiPV VP1 potentially facilitates the accumulation of RSV in SBPH.