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Objective To investigate the effects of chronic intermittent hypoxia on somatotropic axis hormone levels in rats.Methods Mature male Wistar rats were exposed to air or intermittent hypoxia randomly.The serum levels of growth hormone-releasing hormone (GHRH),growth hormone (GH) and somatostatin (SS) were measured before exposure,at the 4th,8th,and 12th week after exposure.Different hormone levels in two groups were compared and analyzed.Results Compared with the control group,GHRH levels in chronic intermittent hypoxic group showed a significant decline at the 4th week [(732.77± 46.99)pg/ml vs.(893.59±40.00) pg/ml,P＜0.05],while SS levels at the 8th week [(30.71 ±2.27) pg/ml vs.(44.69±3.36) pg/ml,P＜0.05] and GH levels at the 12th week [(1.20±0.29) ng/ml vs.(2.06±0.13) ng/ml,P＜0.05]were similarly reduced.As the duration of intermittent hypoxia was prolonged,the GHRH levels did not decrease further [4th week (732.77±46.99) pg/ml vs.8th week (607.54± 131.61) pg/ml vs.12th week (730.05±40.63) pg/ml,P＞0.05].However,the serum SS levels decreased further from the 8th week to the 12th week [(30.71±2.27) pg/ml vs.(24.41±4.06) pg/ml,P＜0.05].Conclusion Chronic intermittent hypoxia might inhibit the function of somatotropic axis.Hypothalamic hormones are the earlyonesto be influenced,thereafter the entire axis.
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Objective To evaluate the accuracy of five blood glucose measurements commonly used in ICU and to determine the potential factors interfering the accuracy. Method This prospective study carried out in consecutively enrolled 49 patients stayed more than 48 hours in the medical ICU of Peking Union Medical College Hospital from November 2007 to January 2008. A total of 130 blood samples were measured to determine blood glucose with five different methods, and the biochemistry analyzer in central laboratory was regarded as reference method for comparison with other four methods, ( 1 ) capillary blood/glucometer;(2) arterial blood/glucometer; (3) arterial blood/blood gas analyzer; and (4) arterial blood/biochemistry analyzer. The accuracy of a method tested was judged by the difference in level of blood glucose between it and reference method, correlation coefficient, bias correction factor and discrepancy. The independent factors for the discrepancies were identified by multivariate logistic regression. Results The values of differences in level of blood glucose between above four methods and the reference were ( 1.7 ± 1.4) mmol/L,( 1.6 ± 1.4 ) mmol/L, ( 1.1 ± 1.2) mmol/L, and (0.5 ± 1.2 ) mmol/L, respectively. The rates of discrepancy were 66.9%, 63.8%, 40.0% and 23.8%. The correlation coefficients were 0. 844, 0. 845, 0. 895and 0. 896. The bias correction factors were 0. 821,0.831,0.914 and 0. 979. Decrease in hematocrit was statistically associated with the discrepancy between glucometer analysis methods and the reference, with OR of 0.923 for capillary blood ( P = 0.03 ) and 0. 912 for arterial blood( P = 0.014), respectively. Conclusions Glucometer analysis poorly correlated with reference method and blood gas analysis in ICU patients. Decrease in hematocrit significantly increased the degree of discrepancy in glucose measurements between glucometer analysis and the reference.
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AIM: To construct the replicative defecient adenovirus Ad-Runx3 expressing Runx3, and to express it in U251 malignant glioblastoma cells. METHODS: The runx3 gene with a flag tag was amplified by PCR using pCMV5-AML2 as a template, and was confirmed by DNA sequencing. The adenovirus shuttle vector pShuttle-CMVRunx3 was constructed by introducing runx3 DNA fragment into the sites of Kpn Ⅰ and Xho Ⅰ of pShuttle-CMV vector. This recombinant plasmid was linearized by Pmel and electronically transfected into BJ5183 cells to get the recombinant adenovirus vector Ad-Runx3. The recombinant adenovirus expressing Runx3 was infected into U251 malignant glioblastoma cells. The expression of exogenous Runx3 was observed by immonoblotting and its localization was detected by immunostaining using anti-Flag tag antibody. RESULTS: The recombinant adenovirus expressing Runx3 with a Flag tag was constructed and infected into U251 glioblastoma cells. The exogenous Runx3 protein was detected only in the nuclei. CONCLUSION: The recombinant adenovirus expressing Runx3 with a Flag tag is constructed successfully, and the Runx3 protein expressed in the nuclei of infected cells. The study laid a foundation for further research of the function of Runx3 in gliocarcinogenesis.
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AIM:To construct a recombinant adenovirus carrying Fhit gene,a tumor suppressor in many types of cancer,and to observe its biological function on the proliferation of colon cancer cells.METHODS:Fhit gene was cloned from the fetal liver cDNA library using the PCR method.The PCR product was inserted into the T vector to construct the plasmid pMD18T-Fhit.The Fhit fragment from the pMD18T-Fhit was inserted into the vector ptrack-CMV to construct a shuttle plasmid ptrack-CMV-Fhit.After PmeI digested and linearized process,ptrack-CMV-Fhit was co-transformed into Escherichia coli strain BJ5183 together with the adenovirus backbone vector pAdEasy-1 to generate a recombinant adenovirus plasmid by homologous recombination.The adenovirus plasmid was identified by PacI digestion and transfected into 293A cells to package a recombinant adenovirus which expressed the Fhit protein.Furthermore,the adenovirus rAd-Fhit was infected into colon cancer cells,and the expression of the ectogenic protein was detected by Western blotting.Finally,the proliferation of colon cancer cells was observed in adenovirus-infected cells by the MTT assay.RESULTS:Constructed the recombinant adenovirus encoding Fhit gene and expressed it in colon cancer cells successfully.Detected that the proliferation of colon cancer cells was inhibited obviously in rAd-Fhit-infected cells with comparison to the control groups.CONCLUSION:Fhit may function as a tumor suppressor in colon cancer cells,and the adenovirus-mediated Fhit can be a novel strategy for the colon cancer therapeutics.
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AIM: To study the effect and mechanism of arsenous oxide (As_2O_3) on pancreatic cancer PC_2 strain. METHODS: The pancreatic cancer PC_2 strain was chosen in this experiment. Apoptosis was detected by TUNEL test. Expression of survivin gene was detected by reverse transcriptase PCR. RESULTS: ① After administration of As_2O_3, the survival number of pancreatic cancer cells decreased significantly in a time-dependent manner (P