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Purpose
This article describes preclinical development of cell-based medicinal products for European markets and discusses European regulatory mechanisms open to developers to aid successful product development. Cell-based medicinal products are diverse, including cells that are autologous or allogeneic, have been genetically modified, or not, or expanded ex vivo, and applied systemically or to an anatomical site different to that of their origin; comments applicable to one product may not be applicable to others, so bespoke development is needed, for all elements - quality, preclinical and clinical.Methods
After establishing how the product is produced, proof of potential for therapeutic efficacy, and then safety, of the product need to be determined. This includes understanding biodistribution, persistence and toxicity, including potential for malignant transformation. These elements need to be considered in the context of the intended clinical development.Results
This article describes regulatory mechanisms available to developers to support product development that aim to resolve scientific issues prior to marketing authorization application, to enable patients to have faster access to the product than would otherwise be the case.Conclusions
Developers are encouraged to be aware of both the scientific issues and regulatory mechanisms to ensure patients can be supplied with these products.25.
Graham F. Whale James Dawick Christopher B. Hughes Delina Lyon Peter J. Boogaard 《Critical reviews in toxicology》2018,48(4):273-296
Gas-to-liquid (GTL) products are synthetic hydrocarbons produced from natural gas using a catalytic process known as the Fischer–Tropsch process. This process yields a synthetic crude oil that consists of saturated hydrocarbons which can subsequently be refined to a range of products analogous to those obtained from petroleum refining. However, in contrast to their petroleum-derived analogs, GTL products are essentially free of unsaturated or aromatic compounds and do not contain any sulfur-, oxygen-, or nitrogen-containing compounds. Under new chemical substance notification requirements, an extensive testing program covering the entire portfolio of GTL products has been undertaken to assess their hazardous properties to human health and environment. The results of these studies have been summarized in a two-part review. Part 1 provides an overview of the mammalian toxicity hazardous properties of the various GTL products. This second part of the review focuses on the aquatic, sediment, terrestrial, and avian toxicity studies which assess the ecotoxicological hazard profile of the GTL products. Many challenges were encountered during these tests relating to dosing, analysis and interpretation of results. These are discussed with the intent to share experiences to help inform and shape future regulatory mandates for testing of poorly soluble complex substances. As was the case with the mammalian toxicology review, there were a few cases where adverse effects were found, but overall the GTL products were found to exert minimal adverse ecotoxicological effects and these were less severe than effects observed with their conventional, petroleum-derived analogs. 相似文献
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Virginia Signal Stephanie Huang Diana Sarfati James Stanley Katherine A. McGlynn 《Nutrition and cancer》2018,70(5):710-736
Dairy consumption has been studied extensively in terms of its relationship with testicular cancer (TC), yet this relationship remains unclear. In this systematic review, we aimed to answer whether TC development is associated with (a) high amounts of dairy product consumption, (b) the type of dairy product consumed, (c) increasing levels of dairy product consumption, and (d) dairy consumption during certain periods during the lifecourse. Following a systematic review of the literature, eight studies (all case-control studies) were included in our review. The included studies varied in terms of the dairy product(s) investigated (milk, cheese, cream, butter, and yoghurt) as well as the type of exposure to dairy consumption (e.g., high vs. low exposure, dose-response, and timing during lifecourse). We found that there was no strong evidence that high levels of dairy consumption are associated with risk of TC, conflicting evidence of a dose–response relationship, inconsistent evidence on whether certain types of dairy are more strongly associated with TC than others, and conflicting evidence that exposure during certain life-course periods affects TC risk more than other periods. There is no consistent evidence to support the premise that dairy product consumption is associated with the risk of TC development. 相似文献
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Arjun K. Venkatesan Robert B. Reed Sungyun Lee Xiangyu Bi David Hanigan Yu Yang James F. Ranville Pierre Herckes Paul Westerhoff 《Bulletin of environmental contamination and toxicology》2018,100(1):120-126
Single particle inductively coupled plasma mass spectrometry (spICP-MS) was used to detect Ti-containing particles in heavily-used bathing areas of a river (Salt River) and five swimming pools. Ti-containing particle concentrations in swimming pools ranged from 2.8?×?103 to 4.4?×?103 particles/mL and were an order of magnitude lower than those detected in the Salt River. Measurements from the Salt River showed an 80% increase in Ti-containing particle concentration over baseline concentration during peak recreational activity (at 16:00 h) in the river. Cloud point extraction followed by transmission electron microscopy with energy dispersive X-ray analysis confirmed presence of aggregated TiO2 particles in river samples, showing morphological similarity to particles present in an over-the-counter sunscreen product. The maximum particle mass concentration detected in a sample from the Salt River (659 ng/L) is only slightly lower than the predicted no effect concentration for TiO2 to aquatic organisms (<?1 μg/L). 相似文献
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ABSTRACTDespite significant health benefits of regular physical activity, over 60 percent of college women do not meet recommended physical activity guidelines to promote their health and health-related quality of life (HRQoL), a comprehensive construct including physical and psychosocial health functioning. The major purpose of this study was to examine the influences of individual (e.g., self-efficacy, enjoyment), social (e.g., family and friend support), and physical environmental factors (e.g., crime safety) on college women’s physical activity and HRQoL. Participants were 235 (Mean age = 21.0 years) college women from a public research university located in the southwest region of the United States. They completed validated surveys assessing their perceptions of physical activity, HRQoL, and social ecological factors during the spring semester of 2012. The findings of three multiple linear regressions, entering individual factors first, followed by social and physical environmental factors, revealed that self-efficacy and crime safety were significantly related to physical activity. For HRQoL-physical functioning, significant factors were self-efficacy, enjoyment, and crime safety. Enjoyment was the only factor related to HRQoL-psychosocial functioning. These findings indicated that physical activity professionals need to foster safe environments, enhance self-efficacy, and provide enjoyable activities to promote college women’s physical activity and HRQoL. 相似文献