AIM: To investigate the inhibitory effect of a specific small survivin interfering RNA (siRNA) on cell proliferation and the expression of survivin in human gastric carcinoma cell line SGC-7901. METHODS: To knockdown ...AIM: To investigate the inhibitory effect of a specific small survivin interfering RNA (siRNA) on cell proliferation and the expression of survivin in human gastric carcinoma cell line SGC-7901. METHODS: To knockdown survivin expression, a small interfering RNA targeting against survivin was synthesized and transfected into SGC-7901 cells with lipofectamineTM2000. The downregulation of survivin expression at both mRNA and protein levels were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. Cell proliferation inhibition rates were determined by methyl thiazolyl tetrazolium (MTT) assay. The effect of survivin siRNA on cell cycle distribution and cell apoptosis was determined by flow cytometry (FCM). RESULTS: RNA interference could efficiently suppress the survivin expression in SGC-7901 cells. At 48 h after transfection, the expression inhibition rate was 44.52% at mRNA level detected by RT-PCR and 40.17% at protein level by Western blot analysis. Downregulation of survivin resulted in significant inhibition of tumor cell growth in vitro. The cell proliferation inhibition rates at 24, 48 and 72 h after survivin siRNA and non-siliencing siRNA transfection, were 34.06%, 47.61% and 40.36%, respectively. The apoptosis rate was 3.56% and the number of cells was increased in G0/G1 phase from 38.2% to 88.6%, and decreased in S and G2/M phase at 48 h after transfection. CONCLUSION: Downregulation of survivin results in significant inhibition of tumor growth in vitro. The inhibition of survivin expression can induce apoptosis of SGC-7901 cells. The use of survivin siRNA deserves further investigation as a novel approach to cancer therapy.展开更多
In face of the everlasting battle toward COVID-19 and the rapid evolution of SARS-CoV-2,no specific and effective drugs for treating this disease have been reported until today.Angiotensin-converting enzyme 2(ACE2),a ...In face of the everlasting battle toward COVID-19 and the rapid evolution of SARS-CoV-2,no specific and effective drugs for treating this disease have been reported until today.Angiotensin-converting enzyme 2(ACE2),a receptor of SARS-CoV-2,mediates the virus infection by binding to spike protein.Although ACE2 is expressed in the lung,kidney,and intestine,its expressing levels are rather low,especially in the lung.Considering the great infectivity of COVID-19,we speculate that SARS-CoV-2 may depend on other routes to facilitate its infection.Here,we first discover an interaction between host cell receptor CD147 and SARS-CoV-2 spike protein.The loss of CD147 or blocking CD147 in Vero E6 and BEAS-2B cell lines by anti-CD147 antibody,Meplazumab,inhibits SARSCoV-2 amplification.Expression of human CD147 allows virus entry into non-susceptible BHK-21 cells,which can be neutralized by CD147 extracellular fragment.Viral loads are detectable in the lungs of human CD147(hCD147)mice infected with SARS-CoV-2,but not in those of virus-infected wild type mice.Interestingly,virions are observed in lymphocytes of lung tissue from a COVID-19 patient.Human T cells with a property of ACE2 natural deficiency can be infected with SARS-CoV-2 pseudovirus in a dosedependent manner,which is specifically inhibited by Meplazumab.Furthermore,CD147 mediates virus entering host cells by endocytosis.Together,our study reveals a novel virus entry route,CD147-spike protein,which provides an important target for developing specific and effective drug against COVID-19.展开更多
AIM:To investigate the impact of postoperative antiviral treatment on tumor recurrence and survival of patients with chronic hepatitis B virus(HBV) or hepatitis C virus(HCV) infection-related primary hepatocellular ca...AIM:To investigate the impact of postoperative antiviral treatment on tumor recurrence and survival of patients with chronic hepatitis B virus(HBV) or hepatitis C virus(HCV) infection-related primary hepatocellular carcinoma(HCC) after curative therapy.METHODS:We performed a meta-analysis of randomized and non-randomized control trials from electronic search and manual search.The fixed effect model of Mantel-Haenszel method and the random effect model of Der Simonian and Laird method were used for homogeneous and heterogeneous studies,respectively.Seven HCV-related studies,three HBV-related studies and three studies on HBV or HCV-related HCC were identified.RESULTS:A total of 1224 patients were included in this analysis.The estimated odds ratios(OR) for the 1-,2-,3-and 5-year recurrence were 0.54 [15.4% vs 24.1%,95% confidence interval(CI):0.32-0.89,P=0.02],0.42(36.9% vs 58.0%,95% CI:0.19-0.90,P=0.03),0.37(47.9% vs 63.8%,95% CI:0.19-0.71,P=0.003),and 0.32(66.7% vs 74.3%,95% CI:0.15-0.66,P=0.002),respectively;and the OR for the 1-,2-,3-,5-and 7-year mortality were 0.23(1.2% vs 9.1%,95% CI:0.07-0.71,P=0.01),0.31(6.4% vs 22.1%,95% CI:0.12-0.79,P=0.01),0.43(12.7% vs 20.8%,95% CI:0.21-0.89,P=0.02),0.42(25.1% vs 42.0%,95% CI:0.27-0.66,P=0.0002) and 0.28(31.9% vs 52.2%,95% CI:0.13-0.59,P=0.0008).CONCLUSION:This meta-analysis indicates the postoperative antiviral therapy,interferon in particular,may serve as a favorable alternative to reduce recurrence and mortality in patients with HBV/HCV related HCCs.展开更多
AIM: To investigate the effect of L-NAME on nitric oxide and gastrointestinal motility alterations in cirrhotic rats. METHODS: Rats with cirrhosis induced by carbon tetrachloride were randomly divided into two groups,...AIM: To investigate the effect of L-NAME on nitric oxide and gastrointestinal motility alterations in cirrhotic rats. METHODS: Rats with cirrhosis induced by carbon tetrachloride were randomly divided into two groups, one n =13 receiving 0.5mg.kg(-1) per day of N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, for 10 days, whereas the other group (n =13) and control (n =10) rats were administrated the same volume of 9g.L(-1) saline. Half gastric emptying time and 2h residual rate were measured by SPECT, using (99m)Tc-DTPA-labeled barium sulfate as test meal. Gastrointestinal transition time was recorded simultaneously. Serum concentration of nitric oxide (NO) was determined by the kinetic cadmium reduction and colorimetric methods. Immunohistochemical SABC method was used to observe the expression and distribution of three types of nitric oxide synthase (NOS) isoforms in the rat gastrointestinal tract. Western blot was used to detect expression of gastrointestinal NOS isoforms. RESULTS: Half gastric emptying time and trans-gastrointestinal time were significantly prolonged(124.0 +/- 26.4 min; 33.7 +/- 8.9 min; 72.1 +/- 15.3 min; P【0.01), (12.4 +/- 0.5h; 9.5 +/- 0.3h; 8.2 +/- 0.8h; P【0.01), 2h residual rate was raised in cirrhotic rats than in controls and cirrhotic rats treated with L-NAME (54.9 +/- 7.6%,13.7 +/- 3.2%, 34.9 +/- 10.3%, P【0.01). Serum concentration of NO was significantly increased in cirrhotic rats than in the other groups (8.20 +/- 2.48) micromol.L(-1), (5.94 +/-1.07) micromol.L(-1) and control (5.66 +/- 1.60 micromol.L(-1), P【0.01. NOS staining intensities which were mainly located in the gastrointestinal tissues were markedly lower in cirrhotic rats than in the controls and cirrhotic rats after treated with L-NAME. CONCLUSION: Gastrointestinal motility was remarkably inhibited in cirrhotic rats, which could be alleviated by L-NAME. Nitric oxide may play an important role in the inhibition of gastrointestinal motility in cirrhotic rats.展开更多
The middle Jurassic Zhiluo Formation in the Dongsheng is comprised of a big set of green sandstone/mudstone with most of uranium orebodies occurring in close proximity to its footwall.By synthesizing field observation...The middle Jurassic Zhiluo Formation in the Dongsheng is comprised of a big set of green sandstone/mudstone with most of uranium orebodies occurring in close proximity to its footwall.By synthesizing field observations,region analysis,data collected from previous coal and uranium borehole,a regional north-south geological profile across the entire orefield is conducted.Experiments on sandstone/mudstone including rock mineral identification,clastic micromorphology and element geochemistry were carried out.Information from the geological profile indicates that green sandstone/mudstone is widely present in a stable horizon with clear boundaries to the country rock.Microscopic observations and geochemical data on sandstone/mudstone exhibit similar mineral composition with almost identical slightly flat,minor Eu enriched,Ce depleted chondrite-normalized REE patterns.Furthermore,the green clay membrane of the clasts has a complex composition containing chlorite/smectite,green smectite,chlorite,and green kaolinite,with elements including Fe,Mg,Si,and Al.These above results indicate that the green sandstone/mudstone underwent resemble sedimentary diagenetic processes as the country rock without transformation by large-scale regional fluid,while the existence of Fe2+-rich membrane is the main factor to the green sandstone/mudstone.Further concentration of the pre-enrichment uranium during diagenetic process led to the final formation for uranium deposits.The above studies are conducive to enrich the metallogenic mechanism of sandstone type uranium deposits and could provide certain reference for uranium exploration and deployment.展开更多
文摘AIM: To investigate the inhibitory effect of a specific small survivin interfering RNA (siRNA) on cell proliferation and the expression of survivin in human gastric carcinoma cell line SGC-7901. METHODS: To knockdown survivin expression, a small interfering RNA targeting against survivin was synthesized and transfected into SGC-7901 cells with lipofectamineTM2000. The downregulation of survivin expression at both mRNA and protein levels were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. Cell proliferation inhibition rates were determined by methyl thiazolyl tetrazolium (MTT) assay. The effect of survivin siRNA on cell cycle distribution and cell apoptosis was determined by flow cytometry (FCM). RESULTS: RNA interference could efficiently suppress the survivin expression in SGC-7901 cells. At 48 h after transfection, the expression inhibition rate was 44.52% at mRNA level detected by RT-PCR and 40.17% at protein level by Western blot analysis. Downregulation of survivin resulted in significant inhibition of tumor cell growth in vitro. The cell proliferation inhibition rates at 24, 48 and 72 h after survivin siRNA and non-siliencing siRNA transfection, were 34.06%, 47.61% and 40.36%, respectively. The apoptosis rate was 3.56% and the number of cells was increased in G0/G1 phase from 38.2% to 88.6%, and decreased in S and G2/M phase at 48 h after transfection. CONCLUSION: Downregulation of survivin results in significant inhibition of tumor growth in vitro. The inhibition of survivin expression can induce apoptosis of SGC-7901 cells. The use of survivin siRNA deserves further investigation as a novel approach to cancer therapy.
基金supported by the National Science and Technology Major Project of China(2019ZX09732-001)the Key R&D Plan Projects in Shaanxi Province(2020ZDXM2-SF-01)Young Talent fund of the University Association for Science and Technology in Shaanxi,China(20200304).
文摘In face of the everlasting battle toward COVID-19 and the rapid evolution of SARS-CoV-2,no specific and effective drugs for treating this disease have been reported until today.Angiotensin-converting enzyme 2(ACE2),a receptor of SARS-CoV-2,mediates the virus infection by binding to spike protein.Although ACE2 is expressed in the lung,kidney,and intestine,its expressing levels are rather low,especially in the lung.Considering the great infectivity of COVID-19,we speculate that SARS-CoV-2 may depend on other routes to facilitate its infection.Here,we first discover an interaction between host cell receptor CD147 and SARS-CoV-2 spike protein.The loss of CD147 or blocking CD147 in Vero E6 and BEAS-2B cell lines by anti-CD147 antibody,Meplazumab,inhibits SARSCoV-2 amplification.Expression of human CD147 allows virus entry into non-susceptible BHK-21 cells,which can be neutralized by CD147 extracellular fragment.Viral loads are detectable in the lungs of human CD147(hCD147)mice infected with SARS-CoV-2,but not in those of virus-infected wild type mice.Interestingly,virions are observed in lymphocytes of lung tissue from a COVID-19 patient.Human T cells with a property of ACE2 natural deficiency can be infected with SARS-CoV-2 pseudovirus in a dosedependent manner,which is specifically inhibited by Meplazumab.Furthermore,CD147 mediates virus entering host cells by endocytosis.Together,our study reveals a novel virus entry route,CD147-spike protein,which provides an important target for developing specific and effective drug against COVID-19.
基金Supported by National Natural Science Foundation of China, No 30970623 and No 30600729International Science and Technology Cooperation Projects, 2010DFA31840
文摘AIM:To investigate the impact of postoperative antiviral treatment on tumor recurrence and survival of patients with chronic hepatitis B virus(HBV) or hepatitis C virus(HCV) infection-related primary hepatocellular carcinoma(HCC) after curative therapy.METHODS:We performed a meta-analysis of randomized and non-randomized control trials from electronic search and manual search.The fixed effect model of Mantel-Haenszel method and the random effect model of Der Simonian and Laird method were used for homogeneous and heterogeneous studies,respectively.Seven HCV-related studies,three HBV-related studies and three studies on HBV or HCV-related HCC were identified.RESULTS:A total of 1224 patients were included in this analysis.The estimated odds ratios(OR) for the 1-,2-,3-and 5-year recurrence were 0.54 [15.4% vs 24.1%,95% confidence interval(CI):0.32-0.89,P=0.02],0.42(36.9% vs 58.0%,95% CI:0.19-0.90,P=0.03),0.37(47.9% vs 63.8%,95% CI:0.19-0.71,P=0.003),and 0.32(66.7% vs 74.3%,95% CI:0.15-0.66,P=0.002),respectively;and the OR for the 1-,2-,3-,5-and 7-year mortality were 0.23(1.2% vs 9.1%,95% CI:0.07-0.71,P=0.01),0.31(6.4% vs 22.1%,95% CI:0.12-0.79,P=0.01),0.43(12.7% vs 20.8%,95% CI:0.21-0.89,P=0.02),0.42(25.1% vs 42.0%,95% CI:0.27-0.66,P=0.0002) and 0.28(31.9% vs 52.2%,95% CI:0.13-0.59,P=0.0008).CONCLUSION:This meta-analysis indicates the postoperative antiviral therapy,interferon in particular,may serve as a favorable alternative to reduce recurrence and mortality in patients with HBV/HCV related HCCs.
基金National Natural Science Foundation of China,No.39970901
文摘AIM: To investigate the effect of L-NAME on nitric oxide and gastrointestinal motility alterations in cirrhotic rats. METHODS: Rats with cirrhosis induced by carbon tetrachloride were randomly divided into two groups, one n =13 receiving 0.5mg.kg(-1) per day of N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, for 10 days, whereas the other group (n =13) and control (n =10) rats were administrated the same volume of 9g.L(-1) saline. Half gastric emptying time and 2h residual rate were measured by SPECT, using (99m)Tc-DTPA-labeled barium sulfate as test meal. Gastrointestinal transition time was recorded simultaneously. Serum concentration of nitric oxide (NO) was determined by the kinetic cadmium reduction and colorimetric methods. Immunohistochemical SABC method was used to observe the expression and distribution of three types of nitric oxide synthase (NOS) isoforms in the rat gastrointestinal tract. Western blot was used to detect expression of gastrointestinal NOS isoforms. RESULTS: Half gastric emptying time and trans-gastrointestinal time were significantly prolonged(124.0 +/- 26.4 min; 33.7 +/- 8.9 min; 72.1 +/- 15.3 min; P【0.01), (12.4 +/- 0.5h; 9.5 +/- 0.3h; 8.2 +/- 0.8h; P【0.01), 2h residual rate was raised in cirrhotic rats than in controls and cirrhotic rats treated with L-NAME (54.9 +/- 7.6%,13.7 +/- 3.2%, 34.9 +/- 10.3%, P【0.01). Serum concentration of NO was significantly increased in cirrhotic rats than in the other groups (8.20 +/- 2.48) micromol.L(-1), (5.94 +/-1.07) micromol.L(-1) and control (5.66 +/- 1.60 micromol.L(-1), P【0.01. NOS staining intensities which were mainly located in the gastrointestinal tissues were markedly lower in cirrhotic rats than in the controls and cirrhotic rats after treated with L-NAME. CONCLUSION: Gastrointestinal motility was remarkably inhibited in cirrhotic rats, which could be alleviated by L-NAME. Nitric oxide may play an important role in the inhibition of gastrointestinal motility in cirrhotic rats.
基金This work was financially and technically supported by National Key Basic Research Program(2015CB453000)of Ministry Science and TechnologyGeological Survey Projects(DD20160127 and DD20160128)from China Geological Surveythe International Geoscience Program(IGCP675)from UNESCO.
文摘The middle Jurassic Zhiluo Formation in the Dongsheng is comprised of a big set of green sandstone/mudstone with most of uranium orebodies occurring in close proximity to its footwall.By synthesizing field observations,region analysis,data collected from previous coal and uranium borehole,a regional north-south geological profile across the entire orefield is conducted.Experiments on sandstone/mudstone including rock mineral identification,clastic micromorphology and element geochemistry were carried out.Information from the geological profile indicates that green sandstone/mudstone is widely present in a stable horizon with clear boundaries to the country rock.Microscopic observations and geochemical data on sandstone/mudstone exhibit similar mineral composition with almost identical slightly flat,minor Eu enriched,Ce depleted chondrite-normalized REE patterns.Furthermore,the green clay membrane of the clasts has a complex composition containing chlorite/smectite,green smectite,chlorite,and green kaolinite,with elements including Fe,Mg,Si,and Al.These above results indicate that the green sandstone/mudstone underwent resemble sedimentary diagenetic processes as the country rock without transformation by large-scale regional fluid,while the existence of Fe2+-rich membrane is the main factor to the green sandstone/mudstone.Further concentration of the pre-enrichment uranium during diagenetic process led to the final formation for uranium deposits.The above studies are conducive to enrich the metallogenic mechanism of sandstone type uranium deposits and could provide certain reference for uranium exploration and deployment.
