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1.
Fish contain many important nutrients and are primarily known for high n-3 polyunsaturated fatty acids (n-3 PUFA) content. Studies have shown that supplementation of fish oil-derived n-3 PUFA improves muscle mass and strength. Here, we hypothesized that fish consumption might improve muscle strength. To test this hypothesis, we performed this cross-sectional study (n = 29,084) in Tianjin, China. The frequency of fish consumption was assessed using a valid self-administered food frequency questionnaire. Handgrip strength (HGS) was used as the indicator of muscle strength, and was measured using a handheld digital dynamometer. Analysis of covariance was used to examine the relationship between fish consumption and HGS. In men, after adjusted potential confounding factors, the least square means (95% confidence intervals) of HGS across saltwater fish consumption categories were 41.5 (41.1, 43.7) kg for <1 time/week, 44.6 (43.2, 45.8) kg for 1 time/week, and 44.7 (43.3, 46.1) kg for ≥2 to 3 times/week (P for trend <0.001). In men, the least square means (95% confidence intervals) of HGS across the ascending quartiles of dietary n-3 PUFA intake were 43.6 (43.2, 44.4) kg, 43.7 (43.2, 44.6) kg, 44.4 (43.0, 45.8) kg, and 44.6 (43.1, 46.0) kg (P for trend <0.01). The results showed that saltwater fish consumption was positively related to HGS in men, but not in women, suggesting that saltwater fish contain nutrients that may be used to improve HGS.  相似文献   
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To protect groundwater as a drinking water resource from microbiological contamination, protection zones are installed. While travelling through these zones, concentrations of potential pathogens should decline to levels that pose no risks to human health. Removal of viruses during subsurface passage is influenced by physicochemical conditions, such as oxygen concentration, which also affects virus survival. The aim of our study was to evaluate the effect of redox conditions on the removal of viruses during sand filtration. Experiments in glass columns filled with medium-grained sand were conducted to investigate virus removal in the presence and absence of dissolved oxygen. Bacteriophages MS2 and PhiX174, as surrogates for human enteric viruses were spiked in pulsed or in continuous mode and pumped through the columns at a filter velocity of about 1 m/d. Virus breakthrough curves were analyzed by calculating total viral elimination and fitted using one-dimensional transport models (CXTFIT and HYDRUS-1D). While short-term experiments with pulsed virus application showed only small differences with regard to virus removal under oxic and anoxic conditions, a long-term experiment with continuous dosing revealed a clearly lower elimination of viruses under anoxic conditions. These findings suggest that less inactivation and less adsorption of viruses in anoxic environments affect their removal. Therefore, in risk assessment studies aimed to secure drinking water resources from viral contamination and optimization of protection zones, the oxic and anoxic conditions in the subsurface should also be considered.  相似文献   
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New Zealand is currently facing an obesity and non communicable diseases (NCDs) epidemic. Recent studies have largely attributed these health issues to insufficient food and low-quality diets that cause micronutrient deficiencies. Improving healthy diets requires broader thinking and collaboration, particularly around maintaining sustainable food systems, which signifies a shift from individualistic/behavioural approaches in health promotion. This paper aims to extend solutions addressing increasing rates of obesity and diet-related NCDs in New Zealand while considering diet and human health in concurrence with sustainability. In particular, the three pillars of sustainability—economic, environmental, and social—will be considered, alongside application of a food systems approach to analysing the epidemic and policy developments in New Zealand. Given its proximity to smaller Pacific islands in the region, New Zealand is in a unique position to work multisectorally and be a leader in considering food system approaches to tackling obesity and NCDs in the Pacific.  相似文献   
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Iron is an essential element for proper functioning of cells within mammalian organ systems; in particular, iron homeostasis is critical for joint health. Excess iron can induce oxidative stress damage, associated with the pathogenesis of iron-storage and ageing-related diseases. Therefore, iron levels in body tissues and cells must be tightly regulated. In the past decades, excess iron content within joints has been found in some patients with joint diseases including hemophilic arthropathy, hemochromatosis arthropathy, and osteoarthritis (OA). Currently, increased evidence has shown that iron accumulation is closely associated with multiple pathological changes of these arthropathies. This review summarizes system-level and intracellular regulation of iron homeostasis, and emphasizes the role of iron in synovial alterations, cartilage degeneration, and subchondral bone of several arthropathies. Of note, we discuss the potential link between iron homeostasis and OA pathogenesis. Finally, we discuss the therapeutic potential of maintaining iron homeostasis in these arthropathies.  相似文献   
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Evidence suggests an association between exposure to cadmium and dysglycemia. To investigate this matter, we examined the relationship between urinary cadmium and prediabetes in the cross sectional National Health and Nutrition Examination Survey (NHANES). NHANES participants for the years 2005 through 2010 aged ≥40 years were included in the analysis. Participants with nephropathy, overt diabetes, or missing required data were excluded. To assess the non-linear relationship between cadmium and Prediabetes, non-parametric logistic regression with B spline expansion of urinary cadmium/creatinine ratio was performed. This analysis revealed a complex non-linear association between higher cadmium levels and prediabetes. This relationship persisted, though with varying magnitudes across smoking groups (never smokers, moderate smokers, heavy smokers). In a conventional logistic regression analysis, this relationship was less evident with significantly increased OR for prediabetes was found in the highest quintile of urine cadmium compared to the lowest quintile in the overall population and in moderate smokers. In an age stratified analysis, a significant linear association was found only in the age groups 60–69 and ≥70. We conclude that there is a significant non-linear, complex relationship between urinary Cd levels, age, smoking habits and odds of prediabetes.  相似文献   
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目的 以结肠癌细胞HCT116为研究对象,评价DNA依赖蛋白激酶催化亚基(DNA-PKcs)抑制剂NU7026对癌干细胞的放射增敏作用及其机制。方法 以CD133+/CD44+为标志物,流式细胞术检测癌干细胞亚群。将HCT116细胞分为对照组、单纯药物(20 μmol/L NU7026)组、单纯照射(2 Gy γ射线)组和药物+照射(20 μmol/L NU7026联合2 Gy γ射线)组,照射前2 h加入NU7026。细胞集落形成实验检测HCT116细胞增殖,流式细胞术检测细胞周期和凋亡, γ-H2AX foci的免疫荧光激光共聚焦分析DNA双链断裂损伤修复。结果 体外培养HCT116细胞中CD133+/CD44+癌干细胞亚群比例高达(88.14±0.47)%,HCT116细胞低密度接种无血清培养基中集落形成率为(84.75±1.35)%。与单纯照射组比较,药物+照射组细胞存活率显著降低(t=7.22,P<0.01)。受照后48 h,药物+照射组的癌干细胞亚群比例较单纯照射组显著降低(t=9.55,P<0.01)。受照后24 h,NU7026明显增加G2/M期阻滞(t=7.67,P<0.01),48 h细胞早期凋亡发生率也明显增加(t=8.24,P<0.05)。药物+照射组在照后2、4、8和24 h DNA双链断裂(γ-H2AX foci)残留比单纯照射组明显增多(t=19.58、11.95、7.01和9.45,P<0.01)。结论 NU7026对癌干细胞为优势亚群的结肠癌HCT116细胞具有明显的放射增敏作用,显著增加对癌干细胞的杀伤效应,增敏机制包括抑制DNA修复,诱发不可逆G2/M期阻滞和增加细胞凋亡。  相似文献   
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Occupational studies show a high risk of lung cancer related to arsenic exposure by inhalation; however, only a few studies, and with conflicting results, previously examined a potential link between arsenic exposure at work and skin cancer. The aim of this study is to assess airborne arsenic exposures at the workplace and to quantify associations with nonmelanoma skin cancer (NMSC). The study sample consists of 618 incident cases of NMSC and 527 hospital‐based controls aged 30–79 years from Hungary, Romania and Slovakia. Exposures were evaluated by local experts using occupational histories. Information on host factors and other exposures was collected and used to adjust the associations of interest using multivariable logistic regression. The lifetime prevalence of exposure to work‐related arsenic is 23.9% for cases and 15.5% for controls. No significant association between arsenic exposure in the workplace and NMSC was detected, although an increased adjusted odd ratio was observed for participants with higher cumulative lifetime workplace exposure to arsenic in dust and fumes compared to referents [odds ratios (OR) = 1.94, 95% confidence interval (CI) = 0.76–4.95]. There is evidence for modification of the workplace arsenic–NMSC association by work‐related sunlight exposure in women, with a markedly increased adjusted OR in the presence of workplace sunlight exposure (OR = 10.22, 95% CI = 2.48–42.07). Workplace coexposure to arsenic and sunlight may thus pose an increased risk of NMSC.  相似文献   
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