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《BONE》2016
Pulsed electromagnetic fields (PEMFs) have been considered as a potential candidate for the prevention and treatment of osteoporosis, however, the mechanism of its action is still elusive. We have previously reported that 50 Hz 0.6 mT PEMFs stimulate osteoblastic differentiation and mineralization in a primary cilium- dependent manner, but did not know the reason. In the current study, we found that the PEMFs promoted osteogenic differentiation and maturation of rat calvarial osteoblasts (ROBs) by activating bone morphogenetic protein BMP-Smad1/5/8 signaling on the condition that primary cilia were normal. Further studies revealed that BMPRII, the primary binding receptor of BMP ligand, was readily and strongly upregulated by PEMF treatment and localized at the bases of primary cilia. Abrogation of primary cilia with small interfering RNA sequence targeting IFT88 abolished the PEMF-induced upregulation of BMPRII and its ciliary localization. Knockdown of BMPRII expression level with RNA interference had no effects on primary cilia but significantly decreased the promoting effect of PEMFs on osteoblastic differentiation and maturation. These results indicated that PEMFs stimulate osteogenic differentiation and maturation of osteoblast by primary cilium-mediated upregulation of BMPRII expression and subsequently activation of BMP-Smad1/5/8 signaling, and that BMPRII is the key component linking primary cilium and BMP-Smad1/5/8 pathway. This study has thus revealed the molecular mechanism for the osteogenic effect of PEMFs. 相似文献
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《结合医学学报(英文版)》2021,19(5):389-394
Clinical trial outcome reporting differs between studies integrating traditional Chinese medicine (TCM) and Western medicine, so that some clinical trials are not eligible for inclusion in a systematic review. The excluded studies are therefore less widely disseminated, and even valid studies are less likely to yield impact. This problem may be addressed by developing core outcome sets (COSs) for integrative medicine in specific healthcare areas. The first stage of development is to define the scope of the COS for integrative medicine, the second stage is to establish the need for such a COS, and the third stage is to develop a protocol and register the COS. The final stage involves three steps: (i) development of a comprehensive list of outcomes (including efficacy outcomes and safety outcomes and TCM syndromes) using systematic review, qualitative or cross-sectional research, and reviews of package inserts and medical records; (ii) merging and grouping of outcomes within domains; (iii) conducting two rounds of Delphi survey and consensus meetings with a range of stakeholders. The final COS will include a general COS and core TCM syndrome- set. Development of COSs for clinical trials of integrative medicine may help to standardize outcome reporting and reduce publication bias in the future. 相似文献
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Melamine is a raw material in the chemical industry. Because of its high nitrogen content, melamine has been utilized by unscrupulous businessmen as a food additive to enhance the indices of protein content in food and feed testing. Tetrahymena has long been used as an excellent model organism in toxicological studies. The purpose of the present study was to determine the effect of melamine on Tetrahymena. In the present study, the effects of melamine on the proliferation and mating rate of Tetrahymena were examined by microscopic counting of the cell numbers. The comet assay and DAPI nuclear staining were performed to analyze the changes in the Tetrahymena genome. Flow cytometric analysis was conducted to detect apoptosis. Furthermore, RT-PCR was performed to determine the changes in the expression of the metallothionein gene in Tetrahymena that underwent stress treatment with varying concentrations of melamine. The results indicated that melamine affected the proliferation and sexual reproduction of Tetrahymena. High melamine concentrations damaged the Tetrahymena genome to a certain extent and induced apoptosis in the organism. Expression of the metallothionein gene was upregulated in Tetrahymena exposed to melamine stress to ameliorate melamine-induced damage. These results indicated that melamine displayed significant toxicity to Tetrahymena cells. 相似文献
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As the causative agent of classical swine fever, the economically devastating swine disease worldwide, classical swine fever virus (CSFV) is currently classified into the 11 subgenotypes, of which subgenotype 2.1 is distributed worldwide and showing more genetic diversity than other subgenotypes. Prior to this report, subgenotype 2.1 was divided into three sub-subgenotypes (2.1a–2.1c). To further analyze the genetic diversity of CSFV isolates in China, 39 CSFV isolates collected between 2004 and 2012 in two Chinese provinces Guangxi and Guangdong were sequenced and subjected to phylogenetic analysis together with reference sequences retrieved from GenBank. Phylogenetic analyses based on the 190-nt and/or 1119-nt full length E2 gene fragments showed that current CSFV subgenotype 2.1 virus isolates in the world could be divided into 10 sub-subgenotypes (2.1a–2.1j) and the 39 isolates collected in this study were grouped into 7 of them (2.1a–2.1c and 2.1g–2.1j). Among the 10 sub-subgenotypes, 2.1d–2.1j were newly identified. Sub-subgenotype 2.1d isolates were circulated only in India, however the rest 9 sub-subgenotypes were from China with some of them closely related to isolates from European and neighboring Asian countries. According to the temporal and spatial distribution of CSFV subgenotype 2.1 isolates, the newly classified 10 sub-subgenotypes were further categorized into three groups: dominant sub-subgenotype, minor sub-subgenotype and silent sub-subgenotype, and each sub-subgenotype can be found only in certain geographical areas. Taken together, this study reveals the complex genetic diversity of CSFV subgenotype 2.1 and improves our understanding about the epidemiological trends of CSFV subgenotype 2.1 in the world, particularly in China. 相似文献
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