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91.
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The incidence of iron deficiency anemia in pregnancy is high in India where iron supplementation is a regular practice. The response to oral iron is influenced by several factors such as age, body mass index, gravida, socioeconomic status, food, vitamin deficiency and compliance to supplements. The major challenge is to understand the various modulators of iron status in this high-risk group so that we can improve the diagnosis and the management of these patients. The current study was designed to evaluate the iron status during pregnancy and to identify factors which might be influencing their response to oral iron. We investigated a total of 181 pregnant women with anemia (Hb < 11 g/dl) and evaluated the impact of probable factors on anemia and their iron status. Assessment of the response was based on hemoglobin and serum ferritin or transferrin saturation level after 8 and 20 weeks of iron supplementation. Socioeconomic, clinical, hematological, biochemical and genetic factors were all evaluated. Molecular analysis revealed that HFE variant allele (G) (rs1799945) was significantly associated with an adequate response to iron supplementation. We identified five subjects with a sustained poor response, and targeted re-sequencing of eleven iron-related genes was performed in them. We have identified seven novel variants in them, and in silico analysis suggested that these variants may have an iron regulatory effect. Taken together, our findings underscore the association of genetic variants with response to supplements in pregnancy, and they can be extended to other diseases where anemia and iron deficiency coexist.

Electronic supplementary material

The online version of this article (doi:10.1007/s12263-015-0474-2) contains supplementary material, which is available to authorized users.  相似文献   
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大绒鼠是中国滇西北鼠疫疫源地的主要储存宿主,它也是横断山脉地区小型哺乳动物的典型代表.用U 检验和相关分析的统计方法对2003~2004年云南洱海(中国滇西北著名的淡水湖泊)周边916只大绒鼠体表寄生虫进行了调查.调查点位于我国十一大鼠疫自然疫源地之一,此地也是我国恙虫病和流行性出血热的流行地区.在此,将大绒鼠的体表寄生虫群落和体表寄生虫医学和兽医学的重要性进行了描述.有756只大绒鼠寄生有体表寄生虫,侵染率为83%.采集到的体表寄生虫有86种,包括51种恙螨, 23种革螨, 7种蚤和5种吸虱.其中17种以前已经被证明是人类疾病的主要媒介.因此大绒鼠很可能成为鼠疫、恙虫病和流行性出血热等病原体的贮存宿主.  相似文献   
95.
中国云南洱海周边小兽体表吸虱多样性   总被引:1,自引:0,他引:1  
在2003—2004年对云南大理洱海周边小兽体表寄生吸虱进行了调查,诱捕小兽3303只,隶属4目7科、15属、21种,共收集14635只吸虱,共计5科、6属、21种。调查点位于洱海周边3个不同方位,恰好处于无量山(洱海东部)、哀牢山(洱海南部)和苍山(洱海西部)3座山的连接地段,由于洱海的天然隔离使这3个方位形成了同地域(经度、纬度、海拔和动物地理区划相同)异生境的地理景观。此项研究的目的是调查同地域异生境里小兽体表吸虱在物种多样性、丰富度、群落结构、相似性和分布。结果表明吸虱的物种多样性低,群落结构简单。吸虱的丰富度、分布和物种多样性随着宿主和生境的不同而存在着显著的差异,这可能暗示着生态环境影响着吸虱和它相对应的小兽宿主的构成和分布。某种宿主经常有某种固定的吸虱,在动物分类上近缘关系较近的小兽宿主,其体表昆虫群落相似性较高。洱海周边不同方位同种小兽宿主上的吸虱物种相同,这个结果强烈暗示着吸虱与其对应宿主之间有明显的协同进化关系。  相似文献   
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Yeast cell wall fractions have been proposed to bind enteropathogenic bacteria. The aim of this study was to develop a quantitative assay by measuring the optical density as growth parameter of adhering bacteria. The exponential growth phase of adhering bacteria was determined by optical density reading and compared with the colony count (CFU/mL). A linear regression was compiled and the bacterial number bound to the yeast cell wall product could be determined. Further focus was the investigation of a yeast cell wall from strain Trichosporon mycotoxinivorans (MTV) for its ability to bind gram negative Salmonella, E. coli and Campylobacter strains and gram positive probiotic bacteria of the genera lactobacilli and bifidobacteria as well as gram positive Clostridium perfringens quantitatively. The gram negative probiotic strain E. coli Nissle 1917 was also investigated. Seven out of 10 S. Typhimurium and S. Enteritidis strains adhered to the cell wall product with an amount between 103 and 104 CFU/10 μg. Four out of 7 E. coli strains showed an average binding capability (102 CFU/10 µg) whereas 4 × 103E. coli F4 cells bound per 10 μg yeast cell wall. E. coli 0149 K91, E. coli 0147 K89, C. jejuni and C. perfringens as well the genera lactobacilli and bifidobacteria did not bind to the yeast cell wall. E. coli Nissle 1917 was bound with 2 × 102 CFU/10 μg. These results demonstrate that cell wall from MTV can be used to differentially bind E. coli spp. and Salmonella spp. up to 8 × 104 CFU/10 μg. Thus certain yeast cell walls may prevent enteric infections caused by selective bacteria. This methodical approach would be an accurate tool in the feed industry for quality control of yeast cell wall products.  相似文献   
98.
The (R)- and (S)-enantiomers of the chiral herbicide napropamide (NAP) show different biological activities and ecotoxicities. These two enantiomers behave differently in the environment due to enantioselective catabolism by microorganisms. However, the molecular mechanisms underlying this enantioselective catabolism remain largely unknown. In this study, the genes (snaH and snpd) involved in the catabolism of NAP were cloned from Sphingobium sp. B2, which was capable of catabolizing both NAP enantiomers. Compared with (R)-NAP, (S)-NAP was much more rapidly transformed by the amidase SnaH, which initially cleaved the amide bonds of (S)/(R)-NAP to form (S)/(R)-2-(1-naphthalenyloxy)-propanoic acid [(S)/(R)-NP] and diethylamine. The α-ketoglutarate-dependent dioxygenase Snpd, showing strict stereoselectivity for (S)-NP, further transformed (S)-NP to 1-naphthol and pyruvate. Molecular docking and site-directed mutagenesis analyses revealed that when the (S)-enantiomers of NAP and NP occupied the active sites, the distance between the ligand molecule and the coordination atom was shorter than that when the (R)-enantiomers occupied the active sites, which facilitated formation of the transition state complex. This study enhances our understanding of the preferential catabolism of the (S)-enantiomer of NAP on the molecular level.  相似文献   
99.
Diabetic cardiomyopathy (DCM) is one of the leading causes of heart failure in patients with diabetes mellitus, with limited effective treatments. The cardioprotective effects of sodium-glucose cotransporter 2(SGLT2) inhibitors have been supported by amounts of clinical trials, which largely fills the gap. However, the underlying mechanism still needs to be further explored, especially in terms of its protection against cardiac fibrosis, a crucial pathophysiological process during the development of DCM. Besides, endothelial-to-mesenchymal transition (EndMT) has been reported to play a pivotal role in fibroblast multiplication and cardiac fibrosis. This study aimed to evaluate the effect of SGLT2 inhibitor dapagliflozin (DAPA) on DCM especially for cardiac fibrosis and explore the underlying mechanism. In vivo, the model of type 2 diabetic rats was built with high-fat feeding and streptozotocin injection. Untreated diabetic rats showed cardiac dysfunction, increased myocardial fibrosis and EndMT, which was attenuated after treatment with DAPA and metformin. In vitro, HUVECs and primary cardiac fibroblasts were treated with DAPA and exposed to high glucose (HG). HG-induced EndMT in HUVECs and collagen secretion of fibroblasts were markedly inhibited by DAPA. Up-regulation of TGF-β/Smad signalling and activity inhibition of AMPKα were also reversed by DAPA treatment. Then, AMPKα siRNA and compound C abrogated the anti-EndMT effects of DAPA in HUVECs. From above all, our study implied that DAPA can protect against DCM and myocardial fibrosis through suppressing fibroblast activation and EndMT via AMPKα-mediated inhibition of TGF-β/Smad signalling.  相似文献   
100.
To assess phylogenetic relationships and speciation modes in Closterium , we sequenced two noncoding regions of the nuclear ribosomal cistron, the 1506 group I intron in small subunit and the internal transcribed spacer 2, for a total of 58 strains of the Closterium moniliferum-ehrenbergii species complex. These include both homothallic and heterothallic C. moniliferum Erenberg ex Ralfs v. moniliferum , heterothallic C. moniliferum v. submoniliferum (Woronichin) Krieger, and heterothallic C. ehrenbergii Meneghini ex Ralfs that can be divided into several mating groups. We found no or very little sequence divergence within single mating groups of C. ehrenbergii and among all heterothallic strains of C. moniliferum v. moniliferum or C. moniliferum v. submoniliferum. Nevertheless, sequence divergence was much greater between those mating groups of C. ehrenbergii and also among the three traditional taxa . Maximum parsimony and maximum likelihood analyses showed that the taxon C. ehrenbergii was not monophyletic. The two varieties of C. moniliferum appeared as a sister clade to certain mating groups of C. ehrenbergii . Among the clades that were recovered in different trees by maximum parsimony and maximum likelihood analyses, we consistently found two large conspicuous clades: clade I consisted of mating groups A, B, C, H, K, and L of C. ehrenbergii whose zygospores have smooth-walls, and clade II contained the mating groups D, E, I, J, and S whose zygospores are scrobiculate. Phylogenetic incongruences observed are discussed from the viewpoints of the different molecular nature of the group I intron and internal transcribed spacer 2, as well as putative rapid diversification of the mating groups and probable ancient ancestral hybridization.  相似文献   
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