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51.
Mothers are often responsible for preparing nutritious foods in their households. However, the quality of mother's diets is often neglected, which may affect both mother's and child's nutrition. Because no single food contains all necessary nutrients, diversity in dietary sources is needed to ensure a quality diet. We aimed to study the association between mother's dietary diversity and stunting in children <2 years attending Dhaka Hospital of icddr,b, a diarrhoeal disease hospital in Dhaka, Bangladesh. A case–control study (n = 296) was conducted from November 2016 to February 2017. Data were collected from mothers of stunted children <2 years (length‐for‐age z score [LAZ] < ?2) as “cases” and nonstunted (LAZ ≥ ?1) children <2 years as “controls.” Mothers were asked to recall consumption of 10 defined food groups 24 hr prior to the interview as per Guidelines for Minimum Dietary Diversity for Women. Among the mothers of cases, 58% consumed <5 food groups during the last 24 hr, compared with 45% in control mothers (P = 0.03). Children whose mothers consumed <5 food groups were 1.7 times more likely to be stunted than children whose mothers consumed ≥5 food groups (P = 0.04). Intake of food groups such as pulses, dairy, eggs, and vitamin A rich fruit was higher in control mothers. Proportion of mother's illiteracy, short stature, monthly family income <BDT 11,480, absence of bank account, and poor sanitation was also found to be higher in stunted group. Further study particularly intervention or longitudinal study to see the causality of mother's dietary diversity with child stunting is recommended.  相似文献   
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In recent times engineered nanoparticles have been receiving much attention from researchers due to their extensive use in a variety of chemical, biological, and industrial areas. Their physiochemical properties have led to a number of uses in commercial products. Considering their broad applications, with increasing human contact the risks of exposure are also increasing. In vivo toxicity experiments involving administering nanoparticles to living organisms have shown their adverse effects on organ development and reproduction. Nanoparticles can be considerably more toxic than the large-sized particles since they can move relatively freely compared to bulkier molecules. Henceforth, it is our duty to assess the harmful health consequences associated with human exposure to nanoparticles in order to improve safe production and use. We will review the current applications of nanoparticles, and issues related to their toxicity. We will focus on safety regulations, risk assessment and regulatory guidelines of nanoparticles. The validation and standardization of nanotoxicity tests will further promote safe applications of nanotechnology in our daily lives.  相似文献   
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The effects of Duranta repens fruits were investigated on H2O2 induced oxidative cell death to evaluate its antioxidative potential in vitro. HEK293T cells were treated with different concentrations [0–1000 µg/ ml] of ethanol extract (E-Ex) and methanol extract (M-Ex) of D. repens for 24h, and then treated with 100 µM H2O2 for 24h. Cell viability, antioxidant parameters of cells, and antioxidant constituents of the extracts were determined. Treatment with limited dose of E-Ex or M-Ex increased the survival rate of H2O2-treated HEK293T cells, however the extra-high dose showed growth inhibitory effect. Treatment with E-Ex or M-Ex protected cellular lipid per-oxidation. In vitro analyses showed the 2,2-diphenyl-1-picrylhydrazyl and H2O2 scavenging activities as well as reducing potential of the extracts. We report here that the limited dose of E-Ex and M-Ex possess antioxidative potential, which can protect H2O2-induced oxidative cell damage.  相似文献   
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Asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous inflammatory disorders of the respiratory tract characterized by airflow obstruction. It is now clear that the environmental factors that drive airway pathology in asthma and COPD, including allergens, viruses, ozone and cigarette smoke, activate innate immune receptors known as pattern-recognition receptors, either directly or indirectly by causing the release of endogenous ligands. Thus, there is now intense research activity focused around understanding the mechanisms by which pattern-recognition receptors sustain the airway inflammatory response, and how these mechanisms might be targeted therapeutically. One pattern-recognition receptor that has recently come to attention in chronic airways disease is the receptor for advanced glycation end products (RAGE). RAGE is a member of the immunoglobulin superfamily of cell surface receptors that recognizes pathogen- and host-derived endogenous ligands to initiate the immune response to tissue injury, infection and inflammation. Although the role of RAGE in lung physiology and pathophysiology is not well understood, recent genome-wide association studies have linked RAGE gene polymorphisms with airflow obstruction. In addition, accumulating data from animal and clinical investigations reveal increased expression of RAGE and its ligands, together with reduced expression of soluble RAGE, an endogenous inhibitor of RAGE signalling, in chronic airways disease. In this review, we discuss recent studies of the ligand–RAGE axis in asthma and COPD, highlight important areas for future research and discuss how this axis might potentially be harnessed for therapeutic benefit in these conditions.  相似文献   
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Given the growing popularity of T1‐weighted/T2‐weighted (T1w/T2w) ratio measurements, the objective of the current study was to evaluate the concordance between T1w/T2w ratios obtained using conventional fast spin echo (FSE) versus combined gradient and spin echo (GRASE) sequences for T2w image acquisition, and to compare the resulting T1w/T2w ratios with histologically validated myelin water fraction (MWF) measurements in several subcortical brain structures. In order to compare these measurements across a relatively wide range of myelin concentrations, whole‐brain T1w magnetization prepared rapid acquisition gradient echo (MPRAGE), T2w FSE and three‐dimensional multi‐echo GRASE data were acquired from 10 participants with multiple sclerosis at 3 T. Then, after high‐dimensional, non‐linear warping, region of interest (ROI) analyses were performed to compare T1w/T2w ratios and MWF estimates (across participants and brain regions) in 11 bilateral white matter (WM) and four bilateral subcortical grey matter (SGM) structures extracted from the JHU_MNI_SS ‘Eve’ atlas. Although the GRASE sequence systematically underestimated T1w/T2w values compared to the FSE sequence (revealed by Bland–Altman and mountain plots), linear regressions across participants and ROIs revealed consistently high correlations between the two methods (r2 = 0.62 for all ROIs, r2 = 0.62 for WM structures and r2 = 0.73 for SGM structures). However, correlations between either FSE‐based or GRASE‐based T1w/T2w ratios and MWFs were extremely low in WM structures (FSE‐based, r2 = 0.000020; GRASE‐based, r2 = 0.0014), low across all ROIs (FSE‐based, r2 = 0.053; GRASE‐based, r2 = 0.029) and moderate in SGM structures (FSE‐based, r2 = 0.20; GRASE‐based, r2 = 0.17). Overall, our findings indicated a high degree of correlation (but not equivalence) between FSE‐based and GRASE‐based T1w/T2w ratios, and low correlations between T1w/T2w ratios and MWFs. This suggests that the two T1w/T2w ratio approaches measure similar facets of subcortical tissue microstructure, whereas T1w/T2w ratios and MWFs appear to be sensitized to different microstructural properties. On this basis, we conclude that multi‐echo GRASE sequences can be used in future studies to efficiently elucidate both general (T1w/T2w ratio) and myelin‐specific (MWF) tissue characteristics.  相似文献   
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