ABSTRACT
Legg-Calvé-Perthes disease (LCPD) is an idiopathic necrosis of the femoral head in childhood, the deformities of the femoral head occurring in the progress of disease could result in osteoarthritis. Treatment can be surgical or nonsurgical, but the timing and indications remain unclear. Understanding of the prognostic factors of LCPD is helpful to predict the outcome and guide the clinical management. This study reviewed the literatures about the prognosis of LCPD since 2000, the prognostic factors were summarized from three categoriesas general factors, disease factors and intervention factors. The general factors were the characteristic information of patient that can be obtained at the first time clinically. The age of onset is the most definite prognostic factor, the younger the age, the better the prognosis, and 6-8 years is an important watershed. Disease factors refer to the disease characteristic information obtained through evaluation. The modified Waldenstr?m stage of the disease needs to be confirmed first, early treatment can ensure better prognosis. Then the severity was evaluated, including the involvement of necrosis, morphological changes and extrusion of the femoral head. The more severe the disease, the worse the prognosis. Most predicters, such as Catterall grading and Herring lateral column typing, have to be used in late-stage of LCPD. The degree of femoral head perfusion evaluated in enhanced MRI or DWI-MRI is an early predictor of LCPD, but it is still in the preliminary exploratory. Intervention factors are the effects of different methods of treatment on prognosis, including the comparison of surgery or non-surgery, different non-surgical and different surgical methods. The determination of surgical or non-surgical treatment mainly depends on the age of onset and severity of disease, and the younger and milder cases tend to be non-surgical treatment, but the specific indications are still controversial.
ABSTRACT
Dioxins, polybrominated diphenyl ethers, and benzo(a)pyrene are common organic pollutants in food. They have been of concern to academics and government administrations due to high residue and persistence, easy accumulation and strong harmful effects. The National Research Council of the United States of America published Toxicity Testing in the 21st Century: A Vision and Strategy in 2007, which proposed a new concept of toxicity testing that toxicity testing should take full consideration of population exposure data and base on in vitro tests, human cell lines, toxicity pathways and high-throughput screening. Meanwhile, systems biology, bioinformatics and rapid assay technologies will be used to better understand toxicity pathways—the cellular response pathways that can lead to adverse health effects when sufficient perturbing induced by chemicals exposure. The new toxicity testing strategy has changed the traditional testing pattern and has brought a wide impact on the international relevant fields. The European Union, the World Health Organization, and the United States Environmental Protection Agency, the Food and Drug Administration, and the National Center for Toxicological Research have organized relevant discussions and exploratory studies to address the new toxicity testing concept and how to evaluate and utilize the results of traditional toxicity test researches. Compared to the discussion, 'whether to do it’, ten years ago, the question, 'how to do it’, has become the concern of the current discussion. Therefore, how to respond to the concept of toxicity testing and how to effectively utilize and excavate traditional toxicity test data have been the focus of multi-disciplines and interdisciplinary academia such as toxicology, food hygiene and environmental science. Therefore, this article provides an overview of the exposure levels of dioxin, polybrominated diphenyl ethers and benzo[a]pyrene, which are typical persistent organic pollutants in food in China and the current research status of toxic pathways based on whole animal experiments. The exposure level, toxic effect and toxicity mechanism of three contaminants are analyzed and summarized in order to provide basis for future results based on the 21st century toxicity test compared with traditional tests and data mining analysis of these two kinds of data. Meanwhile, it also lays the foundation for the establishment of a toxicity testing framework based on exposure characteristics, toxic pathways, and biomarkers.
ABSTRACT
The safety assessment of nanomaterials in food is essential for safeguarding supervision and maintaining public health. However, there are still no safety assessment procedures for nanomaterials established in national-level in China and no specific toxicology and safety assessment procedures about nanomaterials for food, too. These factors lead to restriction on food safety protection and supervision. Current methods of evaluating the safety of nanomaterials mainly rely on traditional toxicological assessment that are extrapolated based on animal experiment from high doses to low doses and from animals to humans. These uncertainties restrict the accuracy of safety assessment for nanomaterials and also limit the development of scientific and effective evaluation procedures and regulatory measures. Currently, the key issues need to be solved including exposure assessment and evaluation methods of nanomaterials in food and the established methods of the toxicity test for nanomaterials that are consistent with the objectives of toxicity test in the 21st century vision and strategy. In this article, we reviewed current administrative regulatory, situations, and existing issues of food nanomaterials either in China or some developed countries in order to provide a scientific basis in establishing safety assessment procedures for nanomaterials in food in the future.