Abstract： Objective To investigate the effect of intramyocardial injection of slow release microspheres of tannic acid （TA） on ventricular remodeling after acute myocardial infarction （AMI） in rats. Methods Slow release microspheres of TA were prepared and the release parameters in vitro were detected. AMI model in rats was induced. Eighty rats were enrolled and divided into 4 groups by random digital table：poly （lactic-co-glycolic acid） （PLGA） microspheres injection （PLGA group， n=24）， PLGA-TA microspheres injection （PLGA-TA group， n=24）， TA injection group （TA group， n=16） and normal saline injection group （NS group， n=16）. Heart function was evaluated by echocardiography after the injection. The structure of cardiac extracellular matrix （ECM） in the infarcted borderline area was evaluated at 4th week after the injection. Collagen content in the infarcted area was evaluated by hydroxyproline colorimetry assay at 2nd and 4th week after the injection. Results TA release was maintained at a constant rate from the microspheres for one month in vitro. Two weeks after the injection， left ventricular ejection fraction（LVEF）， left ventricular fraction shortening（LVFS）， left ventricular end-diastolic diameter（LVEDD） and left ventricular end-systolic diameter（LVESD） in PLGA-TA group and TA group were significantly better than those in the other two groups（P＜0.05）. Four weeks after the injection， LVEF， LVFS， LVEDD and LVESD in PLGA-TA group were significantly better than those in the other three groups （P＜0.05）. Four weeks after the injection， slow release microspheres of TA in the PLGA-TA group effectively improved the arrangement of ECM compared with TA group. Four weeks after the injection， collagen content in the infarcted area of PLGA-TA group was significantly higher than that in TA group（88.88±7.28 μg/mg dry weight vs. 72.43±9.02 μg/mg dry weight）， PLGA group（88.88±7.28 μg/mg drg weight vs. 71.97±6.06 μg/mg dry weight） and NS group（88.88±7.28 μg/mg dry weight vs. 68.86±7.55 μg/mg dry weight， F=7.162，P=0.003）， but there was no statistical difference in the collagen content of the infarcted area among TA group， PLGA group and NS group （P＞0.05） . Conclusion Intramyocardial injection of slow release microspheres of TA can maintain a constant release of TA for a comparatively long period， inhibit collagen matrix degradation， and effectively attenuate ventricular remodeling after AMI in rats.
Objective To study the effect of knockdown of signal transducer and activator of transcription 3 (STAT3) expression by short hairpin RNA (shRNA) on proliferation, apoptosis and invasion of human gastric cancer cell line MKN-45 in vitro . Methods Specific shRNA plasmids to STAT3 were constructed, and then transfected into MKN-45 cells by lipofectamine methods. Cells were divided into three groups: control group, psiRNA-H1 transfected group as negative group and psiRNA-H1/STAT3 transfected group. Semi-quantitative RT-PCR and Western blotting were used to detect the expression of STAT3 mRNA and protein, respectively. Proliferation and apoptosis of the transfected cells were observed by methyl thiazolyl tetrazolium (MTT) method and flow cytometry (FCM), respectively. The invasion of the transfected MKN-45 cells was measured by Boyden chamber. Results Compared with the negative control cells, semi-quantitative RT-PCR and Western blotting showed that the expressions of STAT3 mRNA and protein were down-regulated in the psiRNA-H1/STAT3 transfected group ( P ＜ 0.05) . The subcloned recombinant plasmid expressing shRNA effectively inhibited MKN-45 cell growth and proliferation while empty plasmid had no such specific effect. Cell apoptosis rate increased significantly in psiRNA-H1/STAT3 transfected group （ P ＜ 0.01）, and the invasion of MKN-45 cells was efficiently inhabited in psiRNA-H1/STAT3 transfected group as compared with control group and psiRNA-H1 transfected group( P ＜ 0.01).Conclusion Recombinant plasmid psiRNA-H1/STAT3 shRNA significantly inhibits the proliferation and invasion of MKN-45 cells and promotes their apoptosis.
OBJECTIVE To study the relationship between the changes of mRNA expression in wound tissues of diabetic ulcers and tissue repair. METHODS The mRNA expression of TGF-beta 1 and IL-6 in eight bioptic samples of diabetic ulcers were detected by RT-PCR and pathologic methods, and the surrounding normal skins from the same patients were measured as control group. RESULTS The mRNA expression levels of TGF-beta 1 were markedly decreased in the diabetic ulcers compared with control group, while the mRNA expression levels of IL-6 were increased at the same reaction conditions. CONCLUSION The different changes of mRNA expression level of TGF-beta 1 and IL-6 in wound tissue result in low production and decreased activity of TGF-beta 1 and IL-6, which lower the reparative ability of wound tissue.
Objective To study the protective effect of exogenous matrix metalloproteinases9(MMP-9) inhibitor Doxycycline against lung injury during cardiopulmonary bypass(CPB) in dogs. Methods Twenty healthy mongrel puppies(weighed 10 -12 kg) were divided into control group (n=10) and experimental group(n=10) with random number table. In control group, no measure was taken to protect lung before and after CPB. In experimental group, the feeding food was mixed with Doxycycline (30 mg/kg, body weight) daily for three days before operation. Enzymelinked immunosorbent assay(ELISA) was used to measure the plasma concentration of MMP-9. Hemodynamic and respiratory parameters in two groups were monitored. The preoperative and postoperative alveolararterial oxygen partial pressure difference (A-aDO2) and respiratory index(RI) were calculated. The myeloperoxidase（MPO）activity of bronchoalveolar lavage fluid（BALF）was determined by colorimetry. The total protein of BALF was measured by Coomassie Brilliant Blue G-250. After CPB, light microscope and electronic microscope were used to observe the morphological changes of lung tissue. The dry to wet weight index(W/D) was calculated. Results In both groups, the plasma concentrations of MMP-9 increased significantly as the time of CPB prolonged. The plasma MMP-9 at 150 min and 270 min after CPB in experimental group decreased significantly than those in control group (9.45±5.29 [CM(159mm]ng/ml vs. 18.66±5.90 ng/ml,t=3.664, P=0.005;16.63±2.90 ng/ml -vs.26.17±5.96 ng/ml, t=5.216, P=0.001). MPO activity, total protein of BALF, W/D, postoperative A-aDO2 and RI in experimental group decreased significantly than those in control group. There were significant differences between two groups（t=5.622,P=0.000; t=5.081, P=0.001; t=2.266, P=0.050; t=4.927, P=0.001; t=6.679,P=0.000）. The lung histopathology and electronic microscope showed that the lung injury reduced significantly. Conclusion Doxycycline plays a role in lung protection by inhibiting the secretion of MMP9, reducing the degradation of cell basement membrane, pulmonary neutrophil infiltration and pulmonary edema. Key words: Cardiopulmonary bypass; Acute lung injury; Matrix metalloproteinase; Doxycycline; Lung protection
This paper introduces the application and funding of evidence-based research projects on traditional Chinese medicine (TCM) of the National Natural Science Foundation of China (NSFC) in 2019 in terms of clinical research and methodology research, summarizes the primary problems existing in evidence-based research on TCM, discusses the quality of evidence-based research on TCM in clinical research, highlights the characteristics of TCM and reveals the evidence-based methodology on TCM.
Objectives To analyze evidence-based medicine (EBM) related projects funded by National Natural Science Foundation of China (NSFC) from 2000 to 2019. Methods The online NSFC database, Internet-based Science Information System, Biomart.cn, and MedSci.com were searched to obtain all EBM grants funded by NSFC. The achievements, Chinese papers and SCI-indexed papers, were obtained by searching the database of CNKI, VIP, SinoMed, WanFang Data and Web of Science. All data screened and extracted manually, and then managed and analyzed with Microsoft Excel 2016 software. Results The NSFC has funded 94 projects regarding EBM, with a total amount of 44.763 million Yuan (RMB) since 2000. Beijing, Shanghai, Guangdong and Sichuan ranked highly in the number of projects and their undertaking institutions and total amount of fundings. General programs and youth scientist programs constituted the main parts of fundings. The funded projects mainly originated from three subjects of new technologies and methods of TCM, health management and policy, clinical basis of integrated Chinese and western medicine. General programs contributed the most articles, while the distinguished young scientist programs had the highest average outputs. Three papers from Chinese EBM Center were published on BMJ and were highly cited. Conclusions Support of NSFC on EBM has increased continuously for the last twenty years, but it is still below the average. The fundings are unbalanced in areas and institutions. The supported research fields change every year, and show a trend of subjects aggregation.
ObjectiveTo understand the current situation and challenges of basic research on respiratory diseases in China.MethodsTo summarize and analyze the application and projects funded in the field of respiratory medicine (Code: H01 and H1615) from National Natural Science Foundation of China (NSFC) during 2010 to 2017.ResultsA total of 2 191 projects of 11 766 applications were funded by NSFC in the field of respiratory medicine and the total subsidy fund reached ￥981 279 000. A total of 1 130 projects of 5 915 applications were funded in the Research Projects, including 1 021 General Program projects, 14 Key Program projects, 16 Major Research Plan projects, 1 Major Research Program project, 2 Program projects of Joint Funds, 30 International (Regional) Cooperation and Exchange Program projects, and 46 Emergency Management Program projects. A total of 1 061 projects of 5 851 applications were funded in the Talent Projects, including 853 Young Scientists Fund projects, 191 projects of Fund for Less Developed Regions, 4 projects of Distinguished Young Scholars, 4 projects of Excellent Young Scientists Fund, and 9 projects of the Research Fund for International Young Scientists. The projects funded were mainly distributed in the field of respiratory inflammation and infection, asthma, chronic obstructive pulmonary disease, pulmonary circulation and pulmonary vascular disease. The top three research directions were asthma (19.0%), acute lung injury and acute respiratory distress syndrome (15.4%), chronic obstructive pulmonary disease (12.7%), pulmonary circulation and pulmonary vascular disease (12.7%) in sequence. Average funding rate of respiratory tumor (application code: H1615) was 17.2%.ConclusionsSince the Department of Health Science of NSFC was established in 2009, with the increasing of NSFC budget, the basic research in the field of Respiratory Medicine has been developed rapidly. With the efforts of scientific researchers and clinical medical workers, research in the field of respiratory medicine will achieve rapid development in China.
Abstract: Objective To study the expression of E-selectin on vascular endothelial cells of nude mice liver induced by esophageal carcinoma cells, in order to find out the function of E-selectin in the metastasis of esophageal carcinoma into the liver. Methods Twelve Balb/c nude mice aged from 6 to 8 weeks with their weight ranged between 20 and 25 grams were selected in our research. The mice were equally distributed into the experimental group and the control group(n=6). EC9706 cell solution (5×10.6/0.02 ml) were injected beneath the splenic capsule of the mice in the experimental group. One hour later, spleen was removed. For the mice in the control group, after laparotomy, phosphate buffer without EC 9706 was injected beneath the splenic capsule and spleen was also removed one hour after the injection. Eight hour later, we resected the liver of the nude mice, and expression of E-selectin on vascular endothelial cells of the liver was detected with reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC). Results In the experimental group, 8 hours after injection of EC9706 cells (5×10.6), the results of RT-PCR showed expression of E-selectin mRNA in the liver, and IHC showed a positive protein expression of E-selectin in the cytosol and membrane of hepatic sinus vessels.However, no E-selectin mRNA expression was found in the control group and IHC showed a negative protein expression of E-selectin. Conclusion Human esophageal carcinoma cell line EC9706 can induce balb/c mice liver vascular endothelial cell E-selectin expression, which shows that EC9706 may stay in the liver and form etastatic focus.
Objective To investigate the relationship of p53 codon 72 polymorphism and susceptibility to gastric cancer in high incidence area of Hexi area of Gansu province. Methods The Arg/Pro polymorphism of p53 gene was detected by real-time PCR in 140 patients with gastric cancer, 110 patients with gastric precancerous lesion and 125 healthy controls; Helicobacter pylori (Hp) infection was detected by Warthin-Starry silver method． Results The Pro allele frequencies of p53 gene in gastric cancer cases (0.543) were higher than those in gastric precancerous lesion (0.482) and controls (0.472). The Pro genotype had a more than 1.846 fold increased risk of gastric cancer 〔OR=1.846; 95% 〗CI (1.006-3.387); P =0.046〕． With statistical analysis， the genotype of p53 gene was correlated with location and Laurens histological type （ P ＜ 0.05）. A significantly higher risk of gastric cancer was also seen in cases with p53 Pro genotype, food, Hp infection, positive mind factor and positive family history． Conclusion There is a b correlation between the p53 gene codon 72 Arg/Pro polymophism and susceptibility to gastric cancer in Hexi area of Gansu province and the Pro/Pro genotype may be one of the major risk factors in patients with gastric cancer.
Objective To investigate the application and advancement of hepatocyte t ransplantation ( HCT) .Methods Literatures about the advancement of HCT were reviewed and analyzed. Results There have been manynovel technologies and advancement s in the application of HCT. For example , gene modified cell can be used as seedcell , subcutaneous t ransplantation can be taken when combined with giant molecule material and the encap sulationpreconditioning technique can also carried before operation to improve the rate of survival. Conclusion With moreand deeper understanding of hepatocyte t ransplantation and the development of advanced techniques such as the application of giant molecule , HCT will be extensively used in the clinical t reatment of acute and chronic hepatic diseases.