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861.
Reliable exposure information for cosmetic and other personal care products and ingredients is needed in order to conduct safety assessments. Essential information includes both the amount of product applied, and the frequency of use. To obtain current data, studies to assess consumer use practices were undertaken. Six widely used personal care product types were included in the studies. Five of the products were cosmetics (spray perfume, hairspray, liquid foundation, shampoo, body wash) and one product was a cosmetic/over-the-counter drug product (solid antiperspirant). Three hundred and sixty women, ages 19–65 years, who regularly use the products of interest, were recruited at 10 different geographical locations within the US. The number of recruits was chosen to ensure a minimum of three hundred completed responses per product type. Subjects were provided with a new container of the brand of product they normally use and kept diaries and recorded detailed daily usage information over a two week period. Products were weighed at the start and completion of the study in order to determine the total amount of product used. Statistical analyses of the data were conducted to derive summary distributions of use patterns. The geometric mean and median usage per application, respectively, for the six product types were: spray perfume, 0.33 g and 0.23 g; hairspray, 2.58 g and 1.83 g (aerosol); 3.64 g and 2.66 g (pump); liquid foundation, 0.54 g and 0.36 g; shampoo, 11.76 g and 9.56 g; body wash, 11.3 g and 9.5 g; and solid antiperspirant, 0.61 g and 0.45 g. The mean and median usage per day for the six product types were: spray perfume, 0.53 g and 0.34 g; hairspray, 3.57 g and 2.71 g (aerosol); 5.18 g and 3.74 g (pump); liquid foundation, 0.67 g and 0.45 g; shampoo, 12.80 g and 10.75 g; body wash, 14.5 g and 12.9 g; and solid antiperspirant, 0.79 g and 0.59 g. The mean number of applications per day for spray perfume, hairspray, liquid foundation, shampoo, body wash, and solid antiperspirant was 1.67, 1.49 (aerosol) and 1.51 (pump), 1.24, 1.11, 1.37, and 1.3, respectively. This study provides current exposure information for commonly used products which will be useful for risk assessment purposes.  相似文献   
862.
Vitamin B12 deficiency, mostly of maternal origin in newborns, is a well-treatable condition but can cause severe neurologic sequelae in infants. Early detection of vitamin B12 deficiency allows the pre-symptomatic treatment of affected children. This evaluation assesses the characteristics of maternal vitamin B12 deficiency detected by newborn screening. In a prospective single-center study, a systematic screening strategy for vitamin B12 deficiency using a combination of two second-tier strategies was applied. In addition to confirmatory diagnostics in children, the systematic work-up of vitamin B12 status was also performed for their mothers. Maternal characteristics were assessed including ethnic origin, diet, and vitamin supplementation during pregnancy. For affected mothers, a work-up by internal medicine was recommended. In total, 121 mother–infant couples were analyzed. 66% of mothers adhered to a balanced diet including meat. The cause of maternal vitamin B12 deficiency was unknown in 56% of cases, followed by dietary causes in 32%, and organic causes in 8%. All mothers following a vegan diet and most mothers with a vegetarian diet took vitamin preparations during pregnancy, whereas only 55.8% of mothers with a balanced diet took folic acid or other vitamins. Maternal vitamin B12, folic acid, and homocysteine levels were significantly correlated with the child’s folic acid levels, and with homocysteine, methylmalonic, and methylcitric acid levels in first and second NBS dried blood spots. Most children had normal blood counts and showed normocytosis. Although 36.7% of mothers showed anemia, only one presented with macrocytosis. Adherence to vitamin supplementation in pregnancy is low despite the recommendation for supplementation of folic acid. Ideally, the evaluation of mothers for vitamin B12 levels and appropriate therapy should be initiated in early pregnancy. In infants detected through newborn screening, the multidisciplinary assessment and therapy of both children and mothers should be performed.  相似文献   
863.
864.
Multiple sclerosis (MS) is an autoimmune inflammatory and neurodegenerative disease of the central nervous system (CNS) with increasing incidence and prevalence. MS is associated with inflammatory and metabolic disturbances that, as preliminary human and animal data suggest, might be mediated by disruption of circadian rhythmicity. Nutrition habits can influence the risk for MS, and dietary interventions may be effective in modulating MS disease course. Chronotherapeutic approaches such as time-restricted eating (TRE) may benefit people with MS by stabilizing the circadian clock and restoring immunological and metabolic rhythms, thus potentially counteracting disease progression. This review provides a summary of selected studies on dietary intervention in MS, circadian rhythms, and their disruption in MS, including clock gene variations, circadian hormones, and retino-hypothalamic tract changes. Furthermore, we present studies that reported diurnal variations in MS, which might result from circadian disruption. And lastly, we suggest how chrononutritive approaches like TRE might counteract MS disease activity.  相似文献   
865.
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