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191.
BackgroundCancer is one of the most common causes of death. Excess body weight (EBW), a risk factor for cancer, is highly prevalent in China. We aimed to estimate the number and proportion of cancer deaths attributed to EBW and their changes during 2006–2015 in China.MethodsPopulation attributable fractions in 2006, 2010, and 2015 were calculated with 1) prevalence of overweight/obesity, exacted from the China Health and Nutrition Survey conducted in 8–9 provinces of China in 1997, 2000, and 2004; 2) relative risks for EBW and site-specific cancers, obtained from previous studies; 3) data on cancer deaths in 2006, 2010, and 2015, originated from the Chinese Cancer Registry Annual Report.ResultsIn 2015, EBW contributed to 45,918 (3.1% of all) cancer deaths in China, with 24,978 (2.6%) in men and 20,940 (3.8%) in women. By region, the fraction of cancer deaths attributable to EBW ranged from 1.6% (West) to 4.1% (Northeast). Cancers of liver, stomach, and colorectum were the main EBW-attributable cancers. The fractions of cancer deaths attributable to EBW were 2.4% (95%CI: 0.8–4.2%) in 2006, 2.9% (95%CI: 1.0–5.2%) in 2010, and 3.1% (95%CI: 1.0–5.4%) in 2015, respectively, and increased for all gender, region, and cancer site during 2006–2015.ConclusionsThe proportion of cancer deaths attributed to EBW was higher in women and Northeastern China, with an upward trend in the recent decade. A combination of comprehensive and individualized measures is necessary to reduce the prevalence of EBW and related cancer burden in China.  相似文献   
192.
Alternative ORFs (AltORFs) are unannotated sequences in genome that encode novel peptides or proteins named alternative proteins (AltProts). Although ribosome profiling and bioinformatics predict a large number of AltProts, mass spectrometry as the only direct way of identification is hampered by the short lengths and relative low abundance of AltProts. There is an urgent need for improvement of mass spectrometry methodologies for AltProt identification. Here, we report an approach based on size-exclusion chromatography for simultaneous enrichment and fractionation of AltProts from complex proteome. This method greatly simplifies the variance of AltProts discovery by enriching small proteins smaller than 40 kDa. In a systematic comparison between 10 methods, the approach we reported enabled the discovery of more AltProts with overall higher intensities, with less cost of time and effort compared to other workflows. We applied this approach to identify 89 novel AltProts from mouse liver, 39 of which were differentially expressed between embryonic and adult mice. During embryonic development, the upregulated AltProts were mainly involved in biological pathways on RNA splicing and processing, whereas the AltProts involved in metabolisms were more active in adult livers. Our study not only provides an effective approach for identifying AltProts but also novel AltProts that are potentially important in developmental biology.  相似文献   
193.
We isolated and sequenced Ha hsp 17.9, a DNA complementary (cDNA) of dry-seed stored mRNA that encodes a low-molecular-weight heat-shock protein (LMW HSP). Sequence analysis identified Ha hsp17.9, and the previously reported Ha hsp17.6, as cDNAs encoding proteins (HSP17.6 and HSP17.9) which belong to different families of cytoplasmic LMW HSPs. Using specific antibodies we observed differential expression of both proteins during zygotic embryogenesis under controlled environment, and a remarkable persistence of these LMW HSPs during germination. Immuno-blot analysis of HSP17.9 proteins in two-dimensional gels revealed that the polypeptides expressed in embryos were indistinguishable from LMW HSPs expressed in vegetative tissues in response to water deficit; but they appeared different from homologeous proteins expressed in response to thermal-stress. Tissue-print immunolocalization experiments showed that HSP17.9 and HSP17.6 were homogeneously distributed in every tissue of desiccation-tolerant dry seeds and young seedlings under non-stress conditions. These results demonstrate developmental regulation of specific, cytoplasmic, plant LMW HSPs, suggesting also their involvement in water-stress tolerance.  相似文献   
194.
Cysteine proteinases predominate in the midgut fluid (MF) and oral secretion (OS) of adult western corn rootworm (WCR) based on their mild acidic pH optima (pH 6.0), enhanced activities after treatment with thiol reducing agents, and inhibition by selective cysteine proteinase inhibitors (PIs). Four cysteine PIs including E-64, calpeptin, calpain inhibitor II, and leupeptin (also a serine PI) strongly inhibited azocaseinolytic activity in a dose-dependent manner in both the MF and OS. The most significant effect on adult female WCR of cysteine PI consumption with corn pollen was the reduction in fecundity, but female survival was not apparently affected. Mean fresh weights for all PI-fed females were also lower than control groups. All PI-fed groups [E-64, calpain inhibitor I (Cal I) and leupeptin] had a significantly lower daily egg production than respective corn pollen-fed controls. E-64 was more potent than leupeptin and Cal I on inhibiting fecundity, which correlates with their relative anti-proteinase potency in vitro. E-64, Cal I, and leupeptin at 1.5-2 nmol/beetle/day reduced fecundity down to 25-45% of control values. Reduced egg production by PI-fed beetles results from a combination of the direct inhibition of protein digestion and a post-ingestive negative feedback mechanism, which reduces food intake. The supplement of ten essential amino acids into the E-64-treated pollen enhanced up to 3.7-fold the number of eggs laid compared to the E-64-fed group without these amino acids, suggesting that egg production is dependent on the supply of essential amino acids from corn pollen proteolysis.  相似文献   
195.
增强型绿色荧光蛋白(EGFP)是生物领域常用的标记物. 本实验首先利用高碘酸法活化低分子肝素(LMWH),与EGFP连接得到LMWH EGFP.然后用Sephacryl S-200 HR对其进行初步分离,再用Sephadex G-10 HR进行脱盐纯化. 采用Sephacryl S 200 HR检测LMWH EGFP的纯度,为单一对称峰. 经检测,LMWH-EGFP具有良好的热稳定性和耐碱性. 通过荧光分光检测器检测LMWH-EGFP的λEx为488 nm,λEm为509 nm. 通过抗凝实验发现LMWH EGFP仍具有抗凝活性. 本实验建立了LWMH荧光标记的方法,为多糖的荧光标记提供了新的选择.  相似文献   
196.
Individuals with overweight and obesity are subject to enormous bias and discrimination across domains. This bias constitutes a considerable public health problem beyond the effects of excess weight on health. Unfortunately, the few interventions that have been implemented to reduce this bias have not been successful. Evidence that the presence of an animal makes individuals and settings appear more attractive, desirable, approachable, and relaxed, as well as happier and safer, suggests that dog ownership may be a simple way to reduce weight bias. Accordingly, we tested whether the presence of a dog can reduce weight bias in a sample of 314 online participants. Each participant was presented with a stimulus image representing one of three conditions (person with dog, person with plant, or person alone), and was then asked to rate the human model using three measures. Two sets of stimuli (featuring different models) were used to ensure that findings were not restricted to a particular model. Contrary to our predictions, we found no evidence that the presence of a dog affects endorsement of weight-related stereotypes, general evaluations, or desire for social distance. These findings contrast with a large body of literature showing that dogs enhance perceptions of a range of individuals and settings. The effect of dogs on perceptions may be restricted in the case of weight bias because of the pervasive, explicit, and severe nature of this bias. Dogs may have stronger effects on attitudes that are less openly endorsed. Promising avenues where dogs are very likely to influence attitudes include perceptions of individuals of different racial and ethnic backgrounds, gender identities, and even political parties.  相似文献   
197.
Cysteine (Cys) residues are major causes of crystallin disulfide formation and aggregation in aging and cataractous human lenses. We recently found that disulfide linkages are highly and partly conserved in β- and γ-crystallins, respectively, in human age-related nuclear cataract and glutathione depleted LEGSKO mouse lenses, and could be mimicked by in vitro oxidation. Here we determined which Cys residues are involved in disulfide-mediated crosslinking of recombinant human γD-crystallin (hγD). In vitro diamide oxidation revealed dimer formation by SDS-PAGE and LC-MS analysis with Cys 111-111 and C111-C19 as intermolecular disulfides and Cys 111-109 as intramolecular sites. Mutation of Cys111 to alanine completely abolished dimerization. Addition of αB-crystallin was unable to protect Cys 111 from dimerization. However, Cu2+-induced hγD-crystallin aggregation was suppressed up to 50% and 80% by mutants C109A and C111A, respectively, as well as by total glutathionylation. In contrast to our recently published results using ICAT-labeling method, manual mining of the same database confirmed the specific involvement of Cys111 in disulfides with no free Cys111 detectable in γD-crystallin from old and cataractous human lenses. Surface accessibility studies show that Cys111 in hγD is the most exposed Cys residue (29%), explaining thereby its high propensity toward oxidation and polymerization in the aging lens.  相似文献   
198.
In order to compare the petroleum tolerance and phytoremediation ability of a native grass, Agropyron desertorum (desert Wheatgrass) with Cynodon spp. (Bermuda grass) in a petroleum hydrocarbon-contaminated soil, a 7-month greenhouse experiment was performed. There were 4 soil treatments with 0% (uncontaminated soil), 2%, 4%, and 12% (woil/wsoil) petroleum concentration. Parameters including shoot and root fresh weight and dry weight, root penetration depth and root density depth, soil respiration, and total petroleum hydrocarbons (TPH) degradation were measured during and after experiments. The results showed an increase in shoot fresh weight of A. desertorum in soil polluted with 2% petroleum sludge compared to the uncontaminated soil, whereas the growth of Bermuda grass significantly decreased in corresponding treatment. Root growth of A. desertorum was decreased in 2% and 4% petroleum sludge, whereas it was increased in Bermuda grass species. Overall, root fresh weight of Bermuda grass was higher than that of A. desertorum in all treatments. Significant increase in microorganisms' activity was observed in the presence of petroleum sludge and plants in soil compared with uncontaminated soil without plants, and the highest soil respiration (37.6 mg C-CO2/kg soil day) has been observed in the rhizosphere of Bermuda grass in treatment with 12% petroleum sludge. Plants had a significant role in the degradation of soil contaminants as TPH degradation in planted soils was significantly higher than that in unplanted soil (TPH degradation (%) was 30.4 and 38.9 in A. desertorum and Bermuda grass, respectively, whereas it was just 13.3 in unplanted soil). The rhizosphere of Bermuda grass had significantly less residual TPHs compared to A. desertorum. The results indicated that both Cynodon spp. and A. desertorum had a peculiar tolerance to petroleum pollution. Therefore, as Bermuda grass has already been suggested to be a typical and efficient species for phytoremediating petroleum-contaminated sites, A. desertorum may also prove to be a suitable native alternative.  相似文献   
199.
Birth and first-48-hr death records were analyzed for 10,024 liveborn infants in Mexico City and 12,786 liveborn infants in Santa Cruz, Bolivia. The objective of the analysis was to characterize the early postnatal mortality rates for different types of fetal growth retardation and prematurity. Infants who were delivered prior to 37 weeks of gestation had 23-100 times the mortality risk of infants born at full term and normal weight. Light-for-gestational-age infants (birth weight less than 2,900 g) were further divided into proportionately growth-retarded with normal Rohrer's index (weight/height) and disproportionately growth-retarded with low Rohrer's index. The proportionately growth-retarded infant had nearly twice the mortality of the full-term, appropriate-weight infants, whereas the disproportionately growth-retarded infants had 2.9-5.7 times the mortality rate of the full-term, appropriate-weight infants. There were some differences between samples in mortality rates and prevalence of the different classes of small infants, but the pattern of mortality within samples was consistent between samples.  相似文献   
200.
摘要 目的:探讨注射罗格列酮对多发性骨髓瘤小鼠细胞免疫功能与Caspase-3表达的影响。方法:多发性骨髓瘤小鼠随机平分为三组-模型组、红细胞组与罗格列酮组,红细胞组与罗格列酮组分别给予经尾静脉注射重组鼠源促红细胞生成素5.0 mg/kg与罗格列酮5 mg/kg 100 μL,模型组给予尾静脉注射等体积生理盐水,每天给药1次,检测细胞免疫功能与Caspase-3表达变化情况。结果:三组治疗第7 d与治疗第14 d的肿瘤体积高于治疗第1 d(P<0.05),红细胞组与罗格列酮组低于模型组(P<0.05),罗格列酮组低于红细胞组(P<0.05)。红细胞组与罗格列酮组治疗第7 d与治疗第14 d的血清白介素(Interleukin,IL)-6与肿瘤坏死因子(Tumor necrosis factor,TNF)-α水含量低于模型组(P<0.05),罗格列酮组低于红细胞组(P<0.05)。红细胞组与罗格列酮组治疗第14 d与治疗第28 d的脾脏B淋巴细胞、T淋巴细胞比例对比高于模型组(P<0.05),罗格列酮组高于红细胞组(P<0.05)。红细胞组与罗格列酮组治疗第14 d与治疗第28 d的脑黑质Caspase-3蛋白表达水平低于模型组(P<0.05),罗格列酮组低于红细胞组(P<0.05)。结论:注射罗格列酮在多发性骨髓瘤小鼠的应用能改善细胞免疫功能,抑制脑黑质Caspase-3的表达,同时也能促进小鼠体重恢复,抑制炎症因子的表达。  相似文献   
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