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BACKGROUND:The effect of advanced glycation end products (AGEs) on bone resorption is controversial. Our previous study has shown that bone resorption is significantly inhibited when AGEs present with pre-osteoclast cells RAW 264.7, while the effect of AGEs on osteoclastic acidification remains unknown. OBJECTIVE:To investigate the effect of AGEs on osteoclastic acidification and the underlying mechanism. METHODS:RAW 264.7 cells were induced by RANKL (15μg/L;normal group) to generate osteoclasts, and AGEs (50-400 mg/L;experimental group) or bovine serum albumin (100 mg/L;control group) were added at the beginning of the induction. The effect of AGEs on bone resorption was evaIuated by anaIyzing the area of bone resorption on the Osteo Assay Surface plates, and the effect of AGEs on osteoclastic acidification was evaluated by acridine orange staining. Furthermore, the expression levels of V-ATPase a3 and CIC-7 were detected to investigate the underlying mechanism. RESULTS AND CONCLUSION:The bone resorption area in the AGEs group was significantly decreased compared with the normal group (P<0.05). Acridine orange staining reveaIed that the red fluorescence (620 nm) intensity in the AGEs group was significantly decreased compared with the normal group (P<0.05), and this inhibitory effect became obvious with the increase of AGEs concentration. Immunocytochemistry, western blot assay and PCR findings showed that the expression levels of V-ATPase a3 and CIC-7 in the AGEs group were decreased significantly compared with the normal group (P<0.05). To conclude, AGEs exert inhibitory effect on osteoclastic acidification, probably by inhibiting the expression of V-ATPase a3 and CIC-7.
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Objective To investigate the effect of the teaching method of self design experiment in biochemistry experiment teaching.Methods A total 196 students of Grade 2013 majored in clinical medicine from the Medical College of Shanxi Datong University,were randomly divided into two groups.Students in the control group used traditional teaching method,while students in experimental group were taught with designed experiment teaching method,choosing the experimental project independently,designing and operating the experimental,then summarizing the experiment.After the end of the experiment,the experimental results of each group were evaluated,and the questionnaires were distributed to two groups of students.The teaching effect and the influence on the students were investigated.SPSS 13.0 was used for data processing and the data was made test and t test.Results The experimental grade analysis showed that experimental group was obviously higher than control group in the total score[(83.50 ± 3.27) vs.(65.62 ± 4.20)] and grade of test report[(25.27 ± 1.55) vs.(19.21 ± 2.01)],there was statistically significant (t=33.24,P=0.034;t=23.59,P=0.025),experimental group had significant(t=13.71,P=0.000) higher scores than control group in experimental test scores [(23.41 ± 2.27) vs.(19.42±1.78)],but there was no statistically significant difference (t=23.12,P=0.136) in usually scores[(34.29 ± 2.17) vs.(26.91 ± 2.30)].Survey results showed that the design experiment teaching had very obvious advantages than the traditional teaching method in students' self-study ability (P=0.000),the ability to solve problems (P=0.000) and team spirit of cooperation (P=0.000) culture.Conclusion Compared with traditional teaching method,the self-designed experimental teaching method was better in stimulating students' study interest and analyzing and solving the problem,laying a good foundation for clinical practice of Medical College Students.
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BACKGROUND:The effects of advanced glycation end products (AGEs) on osteoclast-induced bone resorption is controversial and the underlying mechanisms remain unclear. Most of the studies indicate that AGEs can enhance bone resorption, while some othersshowthe opposite effects. OBJECTIVE:To investigate the effects of AGEs on osteoclast-induced inorganicmatrixdissolution and organic componentdegradation and the underlying mechanisms. METHODS:RAW 264.7 cels were induced to generate osteoclasts,and AGEs (50-400 μg/mL) or control-bovine serum albumin (100 μg/mL) was added since the beginning of the induction. The effect of AGEs on bone resorption was evaluated by analyzing the area of resorption pits on the Osteo Assay Surface plates and the expression of cathepsin K. Furthermore, the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cels, nuclei per osteoclasts and the expression of integrinανβ3were detected. RESULTS AND CONCLUSION:The area of resorption pits and expression of cathepsin K in AGEs groups were significantly decreased compared withthecontrol group, and this inhibiting effect became more obvious with the increase of AGEs concentration. TRAP staining also showed that number of TRAP-positivemultinucleated celsand nuclei per osteoclast were significantly reduced in an AGE dose-dependent manner. Quantitative PCR revealed that the expression of integrin ανβ3decreased significantly with the extension of AGEs incubation time. These data indicate that AGEs can exert inhibitory effects on organic and inorganicmatrixdegradation induced by osteoclasts. The underlying mechanism may be involved in the inhibitory effects of AGEs on directed differentiation and cel fusion of osteoclast precursor cels, and migration and adhension of osteoclasts.
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<p><b>OBJECTIVE</b>To evaluate the feasibility of combined high dose leucovorin plus 5-fluorouracil infusion for head-neck and digestive tract cancers.</p><p><b>METHODS</b>Fifty-six patients with head-neck and digestive tract cancer were treated by combined high dose leucovorin (HD-CF) plus 5-fluorouracil (5-Fu) 48 hour continuous infusion with each patient receiving an average of 3.8 cycles (2-6 cycles). Twenty-five of these 56 patients were untreated and 31 recurrent. Their clinical stages were II 4, III 13 and IV 39.</p><p><b>RESULTS</b>The over all response rate (CR + PR) was 35.7% and the clinical beneficial response rate was 80.4%. The main side effects were peripheral phlebitis, suppression of bone marrow, oral ulcer, nausea and vomiting of grade I to II.</p><p><b>CONCLUSION</b>High dose leucovorin plus 5-fluorouracil 48 hour continuous infusion is useful with favorable cost/utility ratio for head-neck and digestive tract cancer patients. Further studies are warranted.</p>