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Klebsiella pneumoniae can cause a variety of infectious diseases, especially in immunocompromised population. The emergence of multidrug-resistant hypervirulent Klebsiella pneumoniae has greatly limited the choice of treatment for Klebsiella pneumoniae infection, and the exploration of new treatment strategies is imminent. In the process of infection, there is a complex interaction between the programmed cell death of host cells and the invasion of Klebsiella pneumoniae. This paper mainly reviewed the research progress in several mechanisms of programmed cell death such as pyroptosis, apoptosis, necroptosis and autophagy caused by Klebsiella pneumoniae.
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BACKGROUND:Currently, the research about effect of non-dextran coated superparamagnetic iron oxide nanoparticles on cellproliferation and cytotoxicity is relatively much less. OBJECTIVE:To evaluate the effects of 0, 25, 50, 75, 100 mg/L non-dextran coated superparamagnetic iron oxide nanoparticles on the proliferation and cytotoxicity of rat bone marrow mesenchymal stem cels. METHODS:Culture media containing 0, 25, 50, 75, 100 mg/L non-dextran coated superparamagnetic iron oxide nanoparticles were prepared for culture of bone marrow mesenchymal stem cels. After 24 hours of culture, the cels were confirmed using Prussian blue staining, and cellcounting was detected using cellcounting kit-8. Meanwhile, lactate dehydrogenase activity in the supernatant and intracelular superoxide dismutase activity were detected. RESULTS AND CONCLUSION:Loading of non-dextran coated superparamagnetic iron oxide nanoparticles in BMSCs was confirmed by Prussian blue staining. The percentage of cels labeled with non-dextran coated superparamagnetic iron oxide nanoparticles was up to 100% when the cels were incubated with a non-dextran coated superparamagnetic iron oxide nanoparticle solution of 50 mg/L and above, but 25 mg/L was insufficient to label al of the cels. Furthermore, as the concentration of non-dextran coated superparamagnetic iron oxide nanoparticles decreased, the cellproliferation rate decreased gradualy. The 25 mg/L group had a minimum cellproliferation rate, but the 25 and 50 mg/L groups showed no statisticaly significant difference (P > 0.05). Therefore, 50 mg/L is considered as the appropriate concentration of non-dextran coated superparamagnetic iron oxide nanoparticles, under which, the labeling efficiency is higher and the cytotoxicity is lower.
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BACKGROUND: Weightlessness is one of the important reasons to cause lower limb muscle atrophy of the astronauts, which is serious harm to the health of astronauts. OBJECTIVE: To explore the progress of weightlessness that cause lower limb muscle atrophy. METHODS: A computer-based online search of PubMed database and CNKI database was performed to search related articles between May 1981 and March 2013 with the key words of “weightless, weightlessness, muscle, atrophy, space” in English and Chinese, respectively. Literatures related to progress of weightlessness that cause lower limb muscle atrophy were selected; in the same field, the literatures published lately in authoritative journals were preferred. RESULTS AND CONCLUSION: A total of 409 literatures were primarily selected, and 47 documents were involved for summary according to the inclusion criteria. The progress of weightlessness that cause muscle atrophy is the hot topic among the space medical research. The main reasons that cause weightlessness muscular atrophy include the reduced muscle spindle neurotrophic factor synthesis caused by reduced information transmission of peripheral sensory nerve, damage of muscle cel ultrastructure, substantial decline in mitochondrial myofibrils, troponin decreasing, decreased intracel ular calcium content, and decreased antigravity muscle blood flow in lower limbs.
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Learning modes based on the initiatives of students has become a new way in the development of medical students' quality.The second clinical medical college of Southern Medical University performed an improved teaching method:meliorated PBL based on TBL and taking clinical and scientific research ability as the core,which combined the advantages of PBL and TBL in view of the importance of clinical and scientific research ability for medical students.Practice proved that this teaching method was effective in improving comprehensive quality of medical students and cultivating more comprehensive talents for the society.