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Human exposure to engineered nanoparticles has become inevitable in today’s extensive commercial use and large-scale production of engineered nanoparticles. Even though several studies have characterised the exposure to nanomaterials during wakeful state (related to occupational exposures and exposures from commercially available particles), very few studies on human exposure during sleep exist. As the study of exposure to all possible nanomaterials during sleep is extensive, this study focuses on exposure to specifically silver nanoparticles which are present in beddings and mattresses. The reasoning behind the use of silver nanoparticles in bedding and related materials, possible routes of entry to various population groups in several sleep positions, exposure characterisation and toxicity potential of such silver nanoparticles are reviewed in this study. The toxicity potential of silver nanoparticles in vivo tests with relation to mammals and in vitro tests on human cells has been tabulated to understand the risks associated during oral, dermal and inhalation exposure to silver nanoparticles. The exposure to humans with regard to dermal absorption and oral intake has been summarised. Although potential inhalation exposure to silver nanoparticles is increasing, only a few studies address the possible toxic effect of inhaled silver particles. Determination of exposure to silver nanoparticles in beddings is a topic that has been less researched, and this review aims to provide background information for future research and help establish a comprehensive risk assessment during sleep in the times of increasing usage of nanoparticles in our daily activities. Despite the current limitations of our understanding, risk assessments must utilise the available data and apply extrapolation procedures in the face of uncertainty, in order to address the needs of regulatory programs. This would enable safe use of the antimicrobial properties of silver nanoparticles without negatively impacting human health. Until then, it would be better to adopt a conservative approach on the usage of silver nanoparticles in daily used commercial items.

  相似文献   
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There are hundreds of contaminated sites with remediation systems that require evaluation and modification to accomplish cleanup goals. These systems are operating well past projected cleanup schedules, cost more than projected to operate, and may not be as protective of human health and the environment as planned. Remediation process optimization (RPO) is an effective method to assess the progress of a system toward achieving cleanup goals within desired time frames and to make the necessary changes in order to reach those goals. Eight main components to the RPO process are evaluated during a review and an implementation plan of recommended changes to the system is developed. Follow‐up and tracking are essential to successful RPO programs. In this article, the authors present a summary of a recent Technical and Regulatory (TechReg) Guidance Document (Interstate Technology and Regulatory Council [ITRC], 2004) and related Technology Overview Series on Advanced Topics in RPO (ITRC, 2006) in a distilled form. © 2007 Wiley Periodicals, Inc.  相似文献   
3.
Administration of endosulfan significantly increased microsomal protein, cytochrome P-450 content and the activity of aminopyrine N-demethylase. Effect of endosulfan and actinomycin D either alone or together on microsomal protein, cytochrome P-450, NADPH cytochrome c reductase, aniline hydroxylase, aminopyrine N-demethylase, phosphatidylcholine content, incorporation of 3H-choline and 14C-methionine were studied in rats given amino acid deficient and supplemented diets. Administration of endosulfan significantly increased the above parameters in both the dietary groups, whereas administration of actinomycin D did not have any effect in rats fed supplemented diets, however, significant decrease in the PC and the incorporation of choline and methionine into PC of rats fed deficient diet were observed. A positive correlation in the effect of endosulfan on hepatic mixed function oxidase activity and hepatic phosphatidylcholine is observed.  相似文献   
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Objective

Carrier screening with reflex to single-gene noninvasive prenatal testing (sgNIPT) is an alternative approach for identifying pregnancies at risk for inherited autosomal recessive conditions without the need for a sample from the reproductive partner. This study is the largest clinical validation of this approach in a general population setting.

Methods

The clinical performance of carrier screening with reflex to sgNIPT for cystic fibrosis, spinal muscular atrophy, alpha thalassemias, and beta hemoglobinopathies was assessed by collecting pregnancy outcome data on patients who underwent this testing and comparing the neonatal outcome to the assay-predicted fetal risk.

Results

Of 42,067 pregnant individuals who underwent screening, 7538 carriers (17.9%) had reflex sgNIPT, and neonatal or fetal outcomes were obtained for 528 cases, including 25 affected pregnancies. Outcomes demonstrated high concordance with sgNIPT, for example, all pregnancies with 9 in 10 personalized fetal risk results were affected (positive predictive value (PPV) of 100% for the sub-group) and the sgNIPT assay showed a sensitivity of 96.0% (95% CI: 79.65%–99.90%), specificity of 95.2% (95% CI: 92.98%–96.92%), average PPV of 50.0% (95% CI: 35.23%–64.77%), and negative predictive value (NPV) of 99.8% (95% CI: 98.84%–99.99%). The end-to-end performance of carrier screening with reflex to sgNIPT was calculated to have a sensitivity of 92.4% and specificity of 99.9%, which are unaffected by partner carrier screening or misattributed paternity unlike a traditional carrier screening workflow, which has a 35% sensitivity and a maximum of 25% PPV (1 in 4) in a real-life setting.

Conclusion

This study builds upon earlier findings to confirm that carrier testing with reflex to sgNIPT is highly accurate for general population screening. Given this high accuracy and an NPV of 99.8%, this workflow should be considered as an option for most of the general pregnant population. When the biological partner sample is unavailable, this workflow should be recommended as the first-line approach.  相似文献   
6.
Abstract

Administration of endosulfan significantly increased microsomal protein, cytochrome P‐450 content and the activity of aminopyrine N‐demethylase. Effect of endosulfan and actinomycin D either alone or together on microsomal protein, cytochrome P‐450, NADPH cytochrome c reductase, aniline hydroxylase, aminopyrine N‐demethylase, phosphatidylcholine content, incorporation of 3H‐choline and 14C‐methionine were studied in rats given amino acid deficient and supplemented diets. Administration of endosulfan significantly increased the above parameters in both the dietary groups, whereas administration of actinomycin D did not have any effect in rats fed supplemented diets, however, significant decrease in the PC and the incorporation of choline and methionine into PC of rats fed deficient diet were observed. A positive correlation in the effect of endosulfan on hepatic mixed function oxidase activity and hepatic phosphatidylcholine is observed.  相似文献   
7.
Capturing flue gases often require multiple stages of scrubbing, increasing the capital and operating costs. So far, no attempt has been made to study the absorption characteristics of all the three gases (NO, SO2 and CO2) in a single stage absorption unit at alkaline pH conditions. We have attempted to capture all the three gases with a single wet scrubbing column. The absorption of all three gases with sodium carbonate solution promoted with oxidizers was investigated in a tall absorption column. The absorbance was found to be 100% for CO2, 30% for NO and 95% for SO2 respectively. The capture efficiency of sodium carbonate solution was increased by 40% for CO2 loading, with the addition of oxidizer. Absorption kinetics and reaction pathways of all the three gases were discussed individually in detail.  相似文献   
8.
CO2 utilizations are essential to curbing the greenhouse gas effect and managing the environmental pollutant in an energy-efficient and economically-sound manner.This paper seeks to critically analyze these technologies in the context of each other and highlight the most important utilization avenues available thus far.This review will introduce and analyze each major pathway,and discuss the overall applicability,potential extent,and major limitations of each of these pathways to util...  相似文献   
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