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861.
目的了解重庆市某三甲医院消毒供应中心(CSSD)纯化水处理系统的细菌水平、消毒方法及效果。方法运用无菌技术采集重庆市某三甲医院CSSD不同时期的纯化水进行细菌培养,根据细菌培养、余氯、硬度检测结果对纯化水处理系统采取一系列措施以改善水质,并对各项措施的实施效果进行评价。结果该院CSSD纯化水存在细菌总数超标的情况,分别经过调整加盐量、更换水处理机耗材、安装含氯消毒剂加药装置并在水处理机制水时将5%84消毒液持续低流量泵入纯化水储水罐后,细菌总数明显降低,纯化水水质达标。结论该院纯化水存在细菌污染现象,医院应加强管理,CSSD需按时维护水处理设备,定期监测水质。 相似文献
862.
目的 分析2011—2020年湖南省伤寒、副伤寒流行特征和菌株耐药情况,为做好伤寒、副伤寒防控工作提供依据。方法 收集2011—2020年湖南省伤寒、副伤寒监测数据,采用描述性流行病学方法分析三间分布特征,对各市州分离上送的67株伤寒、副伤寒沙门菌采用梅里埃VITEK2 Compact 全自动细菌鉴定及药敏分析系统进行细菌鉴定和药敏分析。结果 10年间湖南省共报告伤寒、副伤寒病例9 888例,死亡0例,年均发病率1.47/10万。发病人群以农民、散居儿童、学生为主,5—9月为高发季节,主要集中在湘南和湘西地区。2011—2020年湖南省共报告4起伤寒、副伤寒暴发疫情,暴发场所均为学校,传播途径均为水型传播。67株伤寒、副伤寒菌对头孢他啶、氨曲南和厄他培南100%敏感;对哌拉西林/他唑巴坦、头孢吡肟和复方新诺明敏感率为98.5%;对氨苄西林/舒巴坦敏感率为97.0%;对头孢唑林、头孢替坦、阿米卡星、庆大霉素和妥布霉素敏感性较低(<10%)。55.3%菌株对三类及以上抗生素耐药,发现1株同时对8种抗生素耐药。结论 湖南省伤寒、副伤寒发病呈持续低发状态,局部地区存在暴发。菌株多重耐药现象严重,应加强疫情及耐药监测。 相似文献
863.
Priyanka Sharma Guojun Wu Deeptha Kumaraswamy Natalie Burchat Hong Ye Yongjia Gong Liping Zhao Yan Y. Lam Harini Sampath 《Nutrients》2021,13(2)
7,8-Dihydroxyflavone (DHF) is a naturally occurring flavonoid that has been reported to protect against a variety of pathologies. Chronic administration of DHF prevents high-fat diet (HFD)-induced obesity in female, but not male, mice. However, the mechanisms underlying this sexual dimorphism have not been elucidated. We have discovered that oral DHF supplementation significantly attenuates fat mass, hepatic lipid accumulation, and adipose tissue inflammation in female mice. In contrast, male mice were not protected from adiposity, and had a paradoxical worsening of hepatic lipid accumulation and adipose tissue inflammation upon DHF supplementation. Consistent with these sexually dimorphic effects on body weight and metabolic health, 7,8-DHF induced early and stable remodeling of the female intestinal microbiome. DHF supplementation significantly increased gut microbial diversity, and suppressed potentially detrimental bacteria, particularly Desulfovibrionaceae, which are pro-inflammatory and positively associated with obesity and inflammation. Changes in the female gut microbiome preceded alterations in body weights, and in silico analyses indicated that these early microbial changes were highly predictive of subsequent weight gain in female mice. While some alterations in the intestinal microbiome were also observed in male DHF-supplemented mice, these changes were distinct from those in females and, importantly, were not predictive of subsequent body weight changes in male animals. The temporality of microbial changes preceding alterations in body weight in female mice suggests a role for the gut microbiome in mediating the sexually dimorphic effects of DHF on body weight. Given the significant clinical interest in this flavonoid across a wide range of pathologies, further elucidation of these sexually dimorphic effects will aid the development of effective clinical therapies. 相似文献
864.
Botao Wang Qingmin Kong Shumao Cui Xiu Li Zhennan Gu Jianxin Zhao Hao Zhang Wei Chen Gang Wang 《Nutrients》2021,13(3)
The incidence of obesity, which is closely associated with the gut microbiota and chronic inflammation, has rapidly increased in the past 40 years. Therefore, the probiotic-based modification of the intestinal microbiota composition has been developed as a strategy for the treatment of obesity. In this study, we selected four Bifidobacterium adolescentis strains isolated from the feces of newborn and elderly humans to investigate whether supplementation with B. adolescentis of various origins could alleviate obesity in mice. Male C57BL/6J mice fed a high-fat diet (HFD, 60% energy as fat) received one of the following 14-week interventions: (i) B. adolescentis N4_N3, (ii) B. adolescentis Z25, (iii) B. adolescentis 17_3, (iv) B. adolescentis 2016_7_2, and (v) phosphate-buffered saline. The metabolic parameters, thermogenesis, and immunity of all treated mice were measured. Cecal and colonic microbial profiles were determined by 16S rRNA gene sequencing. Intestinal concentrations of short-chain fatty acids (SCFAs) were measured by gas chromatography-mass spectrometry (GC-MS). The B. adolescentis strains isolated from the feces of elderly humans (B. adolescentis Z25, 17_3, and 2016_7_2) decreased the body weight or weight gain of mice, whilst the strain isolated from the newborn (B. adolescentis N4_N3) increased the body weight of mice. The B. adolescentis strains isolated from the elderly also increased serum leptin concentrations and induced the expression of thermogenesis- and lipid metabolism-related genes in brown adipose tissue. All the B. adolescentis strains alleviated inflammations in the spleen and brain and modified the cecal and colonic microbiota. Particularly, all strains reversed the HFD-induced depletion of Bifidobacterium and reduced the development of beta-lactam resistance. In addition, the B. adolescentis strains isolated from the elderly increased the relative abundances of potentially beneficial genera, such as Bacteroides, Parabacteroides, and Faecalibaculum. We speculate that such increased abundance of commensal bacteria may have mediated the alleviation of obesity, as B. adolescentis supplementation decreased the intestinal production of SCFAs, thereby reducing energy delivery to the host mice. Our results revealed that certain strains of B. adolescentis can alleviate obesity and modify the gut microbiota of mice. The tested strains of B. adolescentis showed different effects on lipid metabolism and immunity regulation, with these effects related to whether they had been isolated from the feces of newborn or elderly humans. This indicates that B. adolescentis from different sources may have disparate effects on host health possibly due to the transmission of origin-specific functions to the host. 相似文献
865.
Shujuan Li Yacong Bo Hongyan Ren Chen Zhou Xiangqian Lao Liyun Zhao Dongmei Yu 《Nutrients》2021,13(4)
Infantile anaemia has been a severe public health problem in China for decades. However, it is unclear whether there are regional differences in the prevalence of anaemia. In this study, we used data from the China Nutrition and Health Surveillance (CNHS) to assess the prevalence of anaemia and the risk factors associated with its prevalence in different regions. We included 9596 infants aged 0–23 months from the CNHS 2013 database. An infant was diagnosed with anaemia if he/she had a haemoglobin concentration of <110 g/L. We used multivariate logistic regression to investigate the potential risk factors associated with the development of anaemia. We found that anaemia was present in 2126 (22.15%) of the infants assessed. Approximately 95% of these cases were classified as mild anaemia. Based on the guidelines laid out by the World Health Organization, 5.5% and 43.6% of the surveillance sites were categorized as having severe and moderate epidemic levels of anaemia, respectively. The prevalence of infantile anaemia in Eastern, Central and Western China was 16.67%, 22.25% and 27.44%, respectively. Premature birth, low birth weight, breastfeeding and residence in Western China were significantly associated with higher odds of developing anaemia. Female sex and having mothers with high levels of education and maternal birth age >25 years were associated with lower odds of developing anaemia. In conclusion, we observed significant regional disparities in the prevalence of infantile anaemia in China. Western China had the highest prevalence of infantile anaemia, and rural regions showed a higher prevalence of anaemia than urban regions. 相似文献
866.
Xiao-Bing Liu Jia-Xi Lu Li-Juan Wang Yi-Chun Hu Rui Wang De-Qian Mao Jian Huang Li-Yun Zhao Xiao-Guang Yang Li-Chen Yang 《Nutrients》2021,13(4)
Objective: The purpose of this study was to evaluate serum zinc status of pregnant women in the China Adult Chronic Disease and Nutrition Surveillance (CACDNS) in 2015–2016. Methods: A total of 7147 apparently healthy pregnant women were randomly selected in 302 national monitoring sites. Information on age, race, residence region, education, pregnancy, and family income per annum was collected, and the concentration of serum zinc was determined. The evaluation of serum zinc status was further performed according to the recommendations by the International Zinc Nutrition Consultative Group (IZiNCG). Results: The median concentration of serum zinc was 858.9 μg/L with an interquartile range (IQR) of 712.9 μg/L and 1048.9 μg/L, while the overall prevalence of zinc deficiency was 3.5% with a 95% confidence interval (CI) of 3.0% and 3.9%. Serum zinc status of pregnant women changed greatly in the different categories, particular in pregnancy and family income per annum (p < 0.05), but no significant difference was observed in the prevalence of zinc deficiency (p > 0.05). Conclusions: The lower prevalence of zinc deficiency generally indicated a better zinc status for pregnant women in the CACDNS in 2015–2016. However, a well-designed evaluation system of zinc status for pregnant women should be continually optimized and improved by inducing more parameters such as biochemical, dietary, or functional indicators. 相似文献
867.
Jian Zhang Ai Zhao Shiyun Lai Qingbin Yuan Xiaojiang Jia Peiyu Wang Yumei Zhang 《Nutrients》2021,13(5)
Our knowledge related to human milk proteins is still limited. The present study determined the changes in multiple human milk proteins during the first six months of lactation, investigated the influencing factors of milk proteins, and explored the impact of milk proteins on infant growth. A total of 105 lactating women and their full-term infants from China were prospectively surveyed in this research. Milk samples were collected at 1–5 days, 8–14 days, 1 month, and 6 months postpartum. Concentrations of total protein and α-lactalbumin were measured in all milk samples, and concentrations of lactoferrin, osteopontin, total casein, β-casein, αs−1 casein, and κ-casein were measured in milk from 51 individuals using ultra performance liquid chromatography coupled with mass spectrometry. The concentration of measured proteins in the milk decreased during the first six months of postpartum (p-trend < 0.001). Maternal age, mode of delivery, maternal education, and income impacted the longitudinal changes in milk proteins (p-interaction < 0.05). Concentrations of αs−1 casein in milk were inversely associated with the weight-for-age Z-scores of the infants (1 m: r −0.29, p 0.038; 6 m: r −0.33, p 0.020). In conclusion, the concentration of proteins in milk decreased over the first six months postpartum, potentially influenced by maternal demographic and delivery factors. Milk protein composition may influence infant weights. 相似文献
868.
Wenwei Lu Yadan Deng Zhifeng Fang Qixiao Zhai Shumao Cui Jianxin Zhao Wei Chen Hao Zhang 《Nutrients》2021,13(6)
Psoriasis is an immune-mediated systemic disease that may be treated with probiotics. In this study, probiotic strains that could or could not decrease interleukin (IL)-17 levels were applied to imiquimod (IMQ)-induced psoriasis-like mice via oral administration. Bifidobacterium adolescentis CCFM667, B. breve CCFM1078, Lacticaseibacillus paracasei CCFM1074, and Limosilactobacillus reuteri CCFM1132 ameliorated psoriasis-like pathological characteristics and suppressed the release of IL-23/T helper cell 17 (Th17) axis-related inflammatory cytokines, whereas B. animalis CCFM1148, L. paracasei CCFM1147, and L. reuteri CCFM1040 neither alleviated the pathological characteristics nor reduced the levels of inflammatory cytokines. All effective strains increased the contents of short-chain fatty acids, which were negatively correlated with the levels of inflammatory cytokines. By performing 16S rRNA gene sequencing, the diversity of gut microbiota in psoriasis-like mice was found to decrease, but all effective strains made some specific changes to the composition of gut microbiota compared to the ineffective strains. Furthermore, except for B. breve CCFM1078, all other effective strains decreased the abundance of the family Rikenellaceae, which was positively correlated with psoriasis-like pathological characteristics and was negatively correlated with propionate levels. These findings demonstrated effects of strain-specificity, and how probiotics ameliorated psoriasis and provide new possibilities for the treatment of psoriasis. 相似文献
869.
Over the past 4 decades, China has experienced a nutritional transition and has developed the largest population of internet users. In this study, we evaluated the impacts of internet access on the nutritional intake in Chinese rural residents. An IV-Probit-based propensity score matching method was used to determine the impact of internet access on nutritional intake. The data were collected from 10,042 rural households in six Chinese provinces. The results reveal that rural residents with internet access have significantly higher energy, protein, and fat intake than those without. Chinese rural residents with internet access consumed 1.35% (28.62 kcal), 5.02% (2.61 g), and 4.33% (3.30 g) more energy, protein, and fat, respectively. There was heterogeneity in regard to the intake of energy, protein, and fat among those in different income groups. Moreover, non-staple food consumption is the main channel through which internet access affects nutritional intake. The results demonstrate that the local population uses the internet to improve their nutritional status. Further studies are required to investigate the impact of internet use on food consumed away from home and micronutrient intake. 相似文献
870.
Manganese (Mn) is a trace nutrient necessary for life but becomes neurotoxic at high concentrations in the brain. The brain is a “privileged” organ that is separated from systemic blood circulation mainly by two barriers. Endothelial cells within the brain form tight junctions and act as the blood–brain barrier (BBB), which physically separates circulating blood from the brain parenchyma. Between the blood and the cerebrospinal fluid (CSF) is the choroid plexus (CP), which is a tissue that acts as the blood–CSF barrier (BCB). Pharmaceuticals, proteins, and metals in the systemic circulation are unable to reach the brain and spinal cord unless transported through either of the two brain barriers. The BBB and the BCB consist of tightly connected cells that fulfill the critical role of neuroprotection and control the exchange of materials between the brain environment and blood circulation. Many recent publications provide insights into Mn transport in vivo or in cell models. In this review, we will focus on the current research regarding Mn metabolism in the brain and discuss the potential roles of the BBB and BCB in maintaining brain Mn homeostasis. 相似文献