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811.
Background
In acupuncture brain imaging trials, there are many non-acupuncture factors confounding the neuronal mapping. The modality of the placebo, subjects’ psychological attitude to acupuncture and their physical state are the three most confounding factors.Objective
To obtain more precise and accurate cerebral fMRI mapping of acupuncture.Design and Setting
A 2×2 randomized, controlled, participant-blinded cross-over factorial acupuncture trial was conducted at Xuanwu Hospital in Beijing, China.Participants
Forty-one college students with myopia were recruited to participate in our study and were allocated randomly to four groups, Group A, Group B, Group C and Group D.Interventions
Group A received real acupuncture (RA) and treatment instruction (TI); Group B received RA and non-treatment instruction (NI); Group C received sham acupuncture (SA) and TI; Group D received SA and NI.Results
Stimulation at LR3 activated some areas of the visual cortex, and the cerebral response to non-acupuncture factors was complex and occurred in multiple areas.Conclusions
The results provide more evidence regarding the credibility of acupuncture therapy and suggest that more precise experimental designs are needed to eliminate sources of bias in acupuncture controlled trials and to obtain sound results. 相似文献812.
Zhiwei Wang Lijuan Zhang Zhi Guo Lei Liu Jun Ji Jianian Zhang Xuehua Chen Bingya Liu Jun Zhang Qiulan Ding Xuefeng Wang Wei Zhao Zhenggang Zhu Yingyan Yu 《PloS one》2012,7(11)
Iron deficiency anemia is an extra-stomach disease experienced in H. pylori carriers. Individuals with type A blood are more prone to suffering from H. pylori infection than other individuals. To clarify the molecular mechanisms underlying H. pylori-associated anemia, we collected erythrocytes from A, B, O, and AB blood donors and analyzed morphology, the number of erythrocytes with H. pylori colonies attached to them, and iron contents in erythrocytes and H. pylori (NCTC11637 and SS1 strains) by means of optical microscopy, scanning electron microscopy, and synchrotron radiation soft X-ray imaging. The number of type A erythrocytes with H. pylori attached to them was significantly higher than that of other erythrocytes (P<0.05). Far more iron distribution was observed in H. pylori bacteria using dual energy analysis near the iron L2, 3 edges by soft X-ray imaging. Iron content was significantly reduced in host erythrocytes after 4 hours of exposure to H. pylori. H. pylori are able to adhere more strongly to type A erythrocytes, and this is related to iron shift from the host to the bacteria. This may explain the reasons for refractory iron deficiency anemia and elevated susceptibility to H. pylori infection in individuals with type A blood. 相似文献
813.
814.
Multidrug resistance (MDR) is a significant challenge to effective cancer chemotherapy treatment. However, the development of a drug delivery system that allows for the sustained release of combined drugs with improved vesicle stability could overcome MDR in cancer cells. To achieve this, we have demonstrated codelivery of doxorubicin (Dox) and paclitaxel (PTX) via a crosslinked multilamellar vesicle (cMLV). This combinatorial delivery system achieves enhanced drug accumulation and retention, in turn resulting in improved cytotoxicity against tumor cells, including drug-resistant cells. Moreover, this delivery approach significantly overcomes MDR by reducing the expression of P-glycoprotein (P-gp) in cancer cells, thus improving antitumor activity in vivo. Thus, by enhancing drug delivery to tumors and lowering the apoptotic threshold of individual drugs, this combinatorial delivery system represents a potentially promising multimodal therapeutic strategy to overcome MDR in cancer therapy. 相似文献
815.
Hui Liu Guangdi Chen Yifeng Pan Zexin Chen Wen Jin Chuan Sun Chunjing Chen Xuanjun Dong Kun Chen Zhengping Xu Shanchun Zhang Yunxian Yu 《PloS one》2014,9(10)
Background
Exposure to electromagnetic field (EMF) emitted by mobile phone and other machineries concerns half the world’s population and raises the problem of their impact on human health. The present study aims to explore the effects of electromagnetic field exposures on sleep quality and sleep duration among workers from electric power plant.Methods
A cross-sectional study was conducted in an electric power plant of Zhejiang Province, China. A total of 854 participants were included in the final analysis. The detailed information of participants was obtained by trained investigators using a structured questionnaire, which including socio-demographic characteristics, lifestyle variables, sleep variables and electromagnetic exposures. Physical examination and venous blood collection were also carried out for every study subject.Results
After grouping daily occupational electromagnetic exposure into three categories, subjects with long daily exposure time had a significantly higher risk of poor sleep quality in comparison to those with short daily exposure time. The adjusted odds ratios were 1.68 (95%CI: 1.18, 2.39) and 1.57 (95%CI: 1.10, 2.24) across tertiles. Additionally, among the subjects with long-term occupational exposure, the longer daily occupational exposure time apparently increased the risk of poor sleep quality (OR (95%CI): 2.12 (1.23∼3.66) in the second tertile; 1.83 (1.07∼3.15) in the third tertile). There was no significant association of long-term occupational exposure duration, monthly electric fee or years of mobile-phone use with sleep quality or sleep duration.Conclusions
The findings showed that daily occupational EMF exposure was positively associated with poor sleep quality. It implies EMF exposure may damage human sleep quality rather than sleep duration. 相似文献816.
817.
SU6656, a selective src family kinase inhibitor, used to probe growth factor signaling 总被引:17,自引:0,他引:17 下载免费PDF全文
Blake RA Broome MA Liu X Wu J Gishizky M Sun L Courtneidge SA 《Molecular and cellular biology》2000,20(23):9018-9027
The use of small-molecule inhibitors to study molecular components of cellular signal transduction pathways provides a means of analysis complementary to currently used techniques, such as antisense, dominant-negative (interfering) mutants and constitutively activated mutants. We have identified and characterized a small-molecule inhibitor, SU6656, which exhibits selectivity for Src and other members of the Src family. A related inhibitor, SU6657, inhibits many kinases, including Src and the platelet-derived growth factor (PDGF) receptor. The use of SU6656 confirmed our previous findings that Src family kinases are required for both Myc induction and DNA synthesis in response to PDGF stimulation of NIH 3T3 fibroblasts. By comparing PDGF-stimulated tyrosine phosphorylation events in untreated and SU6656-treated cells, we found that some substrates (for example, c-Cbl, and protein kinase C delta) were Src family substrates whereas others (for example, phospholipase C-gamma) were not. One protein, the adaptor Shc, was a substrate for both Src family kinases (on tyrosines 239 and 240) and a distinct tyrosine kinase (on tyrosine 317, which is perhaps phosphorylated by the PDGF receptor itself). Microinjection experiments demonstrated that a Shc molecule carrying mutations of tyrosines 239 and 240, in conjunction with an SH2 domain mutation, interfered with PDGF-stimulated DNA synthesis. Deletion of the phosphotyrosine-binding domain also inhibited synthesis. These inhibitions were overcome by heterologous expression of Myc, supporting the hypothesis that Shc functions in the Src pathway. SU6656 should prove a useful additional tool for further dissecting the role of Src kinases in this and other signal transduction pathways. 相似文献
818.
819.
820.
Jiyang Xue Hanwei Ge Zhiyong Lin Hanlei Wang Wei Lin Yong Liu Guowei Wu Jie Xia Qifeng Zhao 《Journal of cellular and molecular medicine》2019,23(4):2849-2862
Inflammatory response plays an important role in ischaemia reperfusion injury (IRI) through a variety of inflammatory cells. Apart from neutrophils, macrophages and lymphocytes, the role of dendritic cells (DCs) in IRI has been noticed. The study was aimed at investigating whether the high‐mobility group protein box‐1/toll like receptor 4 (HMGB1/TLR4) signalling pathway regulate the migration, adhesion and aggregation of DCs to the myocardium, induce DCs activation and maturation, stimulate the expression of surface costimulatory molecules and participate in myocardial IRI. In vivo, migration, adhesion, and aggregation of DCs was enhanced; the expression of peripheral blood DCs CD80 and CD86, myocardial adhesion molecules were increased; and the infarct size was increased during myocardial ischaemia reperfusion injury myocardial ischemic/reperfusion injury (MI/RI). These responses induced by MI/RI were significantly inhibited by HMGB1 specific neutralizing antibody treatment. Cellular experiments confirmed that HMGB1 promoted the release of inflammatory cytokines through TLR4/MyD88/NF‐κB, upregulated CD80 and CD86 expression, mediated the damage of cardiomyocytes and accelerated the apoptosis. Our results indicate that DCs activation and maturation, stimulate the expression of surface costimulatory molecules by promoting the release of inflammatory factors through NF‐κB pathway and participate in myocardial IRI. 相似文献