Since the introduction of antiretroviral therapy (ART), the lifespan and quality of life of patients infected with HIV have been significantly improved. But treatment efficacy was compromised eventually by the develop...Since the introduction of antiretroviral therapy (ART), the lifespan and quality of life of patients infected with HIV have been significantly improved. But treatment efficacy was compromised eventually by the development of resistance to antiretroviral drugs, and more new anti-HIV drugs with lower toxicity and higher activity were needed. Based on the experience and lessons learned from the treatment in the developed countries, US FDA suggested that more pharmacodynamical researches should be considered ahead of the clinical trials. To facilitate the anti-HIV drug research and development, we reviewed a few specialized issues that should be focused on drug evaluations in vitro, including: 1) Mechanism of action studies, demonstrating the candidate drug's efficacy to specifically inhibit viral replication or a virus-specific function and confirm the drug target. 2) Drug resistance studies, selecting the drug-resistant variants in vitro and determining the activities inhibiting HIV isolates resistant to approved antiretroviral drugs of the same class. 3) Antiviral activity in vitro in the presence of serum proteins, ascertaining whether an investigational product is significantly bound by serum proteins. 4) Combination activity analysis, evaluating in vitro antiviral activity of an investigational product in two-drug combinations with other drugs approved.展开更多
Currently available anti-HIV-1 drugs suppress viral replication and maintain viral levels below the detection threshold of most assays but do not eliminate cellular reservoirs. As a result, very low levels of circulat...Currently available anti-HIV-1 drugs suppress viral replication and maintain viral levels below the detection threshold of most assays but do not eliminate cellular reservoirs. As a result, very low levels of circulating virus can be detected in most people despite long-term treatment with potent anti-HIV drug combinations. Not surprisingly, viral levels rebound with discontinuation of treatment. New evidence indicates that there is a viral reservoir in bone marrow progenitor cells.展开更多
To search for the protective actions of blumea flavanones (BFs) on hepatocytes and hepatic subcellular organelle against lipid peroxidation, monkey′s hepatocytes were isolated and cultured with or without blumea flav...To search for the protective actions of blumea flavanones (BFs) on hepatocytes and hepatic subcellular organelle against lipid peroxidation, monkey′s hepatocytes were isolated and cultured with or without blumea flavanones, then damaged by FeSO 4 cysteine or CCl 4. The lipid peroxidation (malondialdehyde production) and alteration in hepatocyte membrane (leakage of GPT) were estimated. Hepatic subcellular organelles were also isolated and incubated with or without blumea flavanones, then injured by FeSO 4 ascorbate. The generation of malondialdehyde(MDA) was measured. It was found that BFs 10 and 100 μmol·L 1 inhibited the MDA generation and GPT (glutamic pyruvic transaminase) leakage out of hepatocytes that were induced by CCl 4 or FeSO 4 cysteine. BFs could prevent lipid peroxidation initiated by FeSO 4 ascorbate in subcellular organelle suspension. Among BFs, BF 2 possessed the strongest activity. Conclusion: Blumea flavanones possess antioxidation activities that protect monkey′s hepatocytes and hepatic subcellular organelle against injuries induced by FeSO4 or CCl 4.展开更多
Neutralizing antibodies are recognized to be one of the essential elements of the adaptive immune response that must be induced by an effective vaccine against HIV. However, only a limited number of antibodies have be...Neutralizing antibodies are recognized to be one of the essential elements of the adaptive immune response that must be induced by an effective vaccine against HIV. However, only a limited number of antibodies have been identified to neutralize a broad range of primary isolates of HIV-1 and attempts to induce such antibodies by inununization were unsuccessful. The difficulties to generate such antibodies are mainly due to intrinsic properties of HIV-1 envelope spikes, such as high sequence diversity, heavy glycosylation, and inducible and transient nature of certain epitopes. In vitro neutralizing antibodies are identified using "conventional" neutralization assay which uses phytohemagglutinin (PHA)-stimulated human PBMCs as target cells. Thus, in essence the assay evaluates HIV-1 replication in CD4^+T cells. Recently, several laboratories including us demonstrated that some monoclonal antibodies and HIV-1-specific polyclonal IgG purified from patient sera, although they do not have neutralizing activity when tested by the "conventional" neutralization assay, do exhibit potent and broad neutralizing activity in "unconventional" ways. The neutralizing activity of these antibodies and IgG fractions is acquired through post-translational modifications, through opsonization of virus particles into macrophages and inunature dendritic cells (iDCs), or through expression of antibodies on the surface of HIV-1-susceptible cells. This review will focus on recent findings of this area and point out their potential applications in the development of preventive strategies against HIV.展开更多
The synergetic cytocidal effect of ascorbic acid and mitomycin C on Ehrlich as-cites tumor cells in culture was studied. The chain scission of DNA by Cu(Ⅱ)mitomycin C/ascorbic acid system,and the chemical kinetics of...The synergetic cytocidal effect of ascorbic acid and mitomycin C on Ehrlich as-cites tumor cells in culture was studied. The chain scission of DNA by Cu(Ⅱ)mitomycin C/ascorbic acid system,and the chemical kinetics of the Cu(Ⅱ) catalyzed aerobic oxidation of ascorbic acid in the presence of mitomycin C were also discussed. Experimental results showed that ascorbic acid and mitomycin C were synergetic in destroying Ehrlich ascites tumor cells.The effect is related to the breaking action of the Cu(Ⅱ)mitomycin C/ascorbic acid system on the DNA chain, and to the quantity of the system produced ·OH, and the speed of production which are both directly proportional to the concentration of ascorbic aci.These results imply that the ·OH produced in the aerobic oxidation of ascorbic acid,and·OH induced scission of DNA chain, are important factors to he synergetic cytocidal effect of ascorbic acid and mitomycin C on Ehrlich ascites tumor cells.展开更多
HIV/AIDS is one of the most serious public health challenges globally. Despite the great efforts that are being devoted to prevent,treat and to better understand the disease,it is one of the main causes of morbidity a...HIV/AIDS is one of the most serious public health challenges globally. Despite the great efforts that are being devoted to prevent,treat and to better understand the disease,it is one of the main causes of morbidity and mortality worldwide. Currently,there are 30 drugs or combinations of drugs approved by FDA. Because of the side-effects,price and drug resistance,it is essential to discover new targets,to develop new technology and to find new anti-HIV drugs. This review summarizes the major targets and assays currently used in anti-HIV drug screening.展开更多
Squamous cell carcinoma of the anus (SCCA) is a com- mon cancer in the human immunodeficiency virus (HIV)- infected population, and its incidence continues to in- crease in male homosexuals. Combined chemoradiatio...Squamous cell carcinoma of the anus (SCCA) is a com- mon cancer in the human immunodeficiency virus (HIV)- infected population, and its incidence continues to in- crease in male homosexuals. Combined chemoradiation with mitomycin C and 5-fiuorouracil was poorly tolerated by severely immunocompromised patients in the early 1990s. In the era of highly active antiretroviral therapy (HAART), however, recent data indicate that: (1) most HIV patients with anal cancer can tolerate standard chemotherapy regimens; and (2) this approach is associ- ated with survival rates similar to those of HIV-negative patients. However, HIV-positive patients with SCCA are much younger, more likely to develop local tumor recur- rence, and ultimately die from anal cancer than immune competent patients. Taken together, these findings suggest that anal cancer is an often fatal neoplasia in mid- dle-aged HIV-positive male homosexuals. In this popula- tion, SCCA is an opportunistic disease resulting in patients with suboptimal immune function from persistent infection and prolonged exposition to oncogenic human papillomaviruses (HPVs). Large-scale cancer-prevention strategies (routine anuscopy and anal papanicolaou test- ing) should be implemented in this population. In addi- tion, definitive eradication of oncogenic HPVs within the anogenital mucosa of high-risk individuals might require a proactive approach with repeated vaccination.展开更多
Many plants contain ribosome inactivating proteins (RIPs) with N-glycosidase activity, which depurinate large ribosomal RNA and arrest protein synthesis. RIPs so far tested inhibit replication of mRNA as well as DNA v...Many plants contain ribosome inactivating proteins (RIPs) with N-glycosidase activity, which depurinate large ribosomal RNA and arrest protein synthesis. RIPs so far tested inhibit replication of mRNA as well as DNA viruses and these proteins, isolated from plants, are found to be effective against a broad range of viruses such as human immunodeficiency virus (HIV), hepatitis B virus (HBV) and herpes simplex virus (HSV). Most of the research work related to RIPs has been focused on antiviral activity against HIV; however, the exact mechanism of antiviral activity is still not clear. The mechanism of antiviral activity was thought to follow inactivation of the host cell ribosome, leading to inhibition of viral protein translation and host cell death. Enzymatic activity of RIPs is not limited to depurination of the large rRNA, in addition they can depurinate viral DNA as well as RNA. Recently, Phase I/II clinical trials have demonstrated the potential use of RIPs for treating patients with HIV disease. The aim of this review is to focus on various RIPs from plants associated with anti-HIV activity.展开更多
Objective: To construct bicistronic expression vector with RANTES and SDF-1 genes, the ligands of HIV-1 principal coreceptors, and identify its expression. Methods: RANTES-KDEL was amplified from plasmid pCMV-R-K by P...Objective: To construct bicistronic expression vector with RANTES and SDF-1 genes, the ligands of HIV-1 principal coreceptors, and identify its expression. Methods: RANTES-KDEL was amplified from plasmid pCMV-R-K by PCR and cloned into eukaryotic expression vector pCMV-S/K. Gene transfection into HeLa cells was carried out by lipofectin. Indirect immumofluorescence and radioimmunoprecipitation were used to confirm the expression of RANTES and SDF-1. Results: The construction of pCMV-R-K-S-K was confirmed by enzymatic digestion and sequencing. RANTES and SDF-1 were shown expressed in HeLa cells by indirect immumofluorescence and radioimmunoprecipitation. Conclusion: pCMV-R-K-S-K was constructed and expressed in cell line Hela successfully, which will contribute to further study of gene therapy of AIDS by HIV-1 coreceptors knockout.展开更多
AIM: To analyze the influence of human immunodeficiency virus (HIV) infection on the course of hepatitis C virus (HCV) infection. METHODS: We performed a meta-analysis to quantify the effect of HIV co-infection on pro...AIM: To analyze the influence of human immunodeficiency virus (HIV) infection on the course of hepatitis C virus (HCV) infection. METHODS: We performed a meta-analysis to quantify the effect of HIV co-infection on progressive liver disease in patients with HCV infection. Published studies in the English or Chinese-language medical literature involving cohorts of HIV-negative and -positive patients coinfected with HCV were obtained by searching the PUBMED, EMBASE and CBM. Data were extracted independently from relevant studies by 2 investigators and used in a fixed-effect meta analysis to determine the difference in the course of HCV infection in the 2 groups. RESULTS: Twenty-nine trails involving 16 750 patients were identified including the outcome of histological fibrosis or cirrhosis or de-compensated liver disease or hepatocellular carcinoma or death. These studies yielded a combined adjusted odds ratio (OR) of 3.40 [95% confidence interval (CI) = 2.45 and 4.73]. Of note, studies that examined histological fibrosis/ cirrhosis, decompensated liver disease, hepatocellular carcinoma or death had a pooled OR of 1.47 (95% CI = 1.27 and 1.70), 5.45 (95% CI = 2.54 and 11.71), 0.76 (95% CI = 0.50 and 1.14), and 3.60 (95% CI = 3.12 and 4.15), respectively. CONCLUSION: Without highly active antiretroviral therapies (HAART), HIV accelerates HCV diseaseprogression, including death, histological fibrosis/ cirrhosis and decompensated liver disease. However, the rate of hepatocellular carcinoma is similar in persons who had HCV infection and were positive for HIV or negative for HIV.展开更多
The need for an efficacious HIV/AIDS vaccine remains the highest priority of the world HIV/AIDS agenda. The generation of an efficacious HIV/AIDS vaccine proves an enormous scientific challenge. This article reviews t...The need for an efficacious HIV/AIDS vaccine remains the highest priority of the world HIV/AIDS agenda. The generation of an efficacious HIV/AIDS vaccine proves an enormous scientific challenge. This article reviews the neutralizing antibody problem,elusive immune protection,im-munogen design,pre-existing anti-vector immunity and design of phase 3 vaccine trials and the challenges and opportunities in development of HIV/AIDS vaccine are discussed.展开更多
基金supported by Major Science and Technology Special Projects (2009 ZX09301)
文摘Since the introduction of antiretroviral therapy (ART), the lifespan and quality of life of patients infected with HIV have been significantly improved. But treatment efficacy was compromised eventually by the development of resistance to antiretroviral drugs, and more new anti-HIV drugs with lower toxicity and higher activity were needed. Based on the experience and lessons learned from the treatment in the developed countries, US FDA suggested that more pharmacodynamical researches should be considered ahead of the clinical trials. To facilitate the anti-HIV drug research and development, we reviewed a few specialized issues that should be focused on drug evaluations in vitro, including: 1) Mechanism of action studies, demonstrating the candidate drug's efficacy to specifically inhibit viral replication or a virus-specific function and confirm the drug target. 2) Drug resistance studies, selecting the drug-resistant variants in vitro and determining the activities inhibiting HIV isolates resistant to approved antiretroviral drugs of the same class. 3) Antiviral activity in vitro in the presence of serum proteins, ascertaining whether an investigational product is significantly bound by serum proteins. 4) Combination activity analysis, evaluating in vitro antiviral activity of an investigational product in two-drug combinations with other drugs approved.
文摘Currently available anti-HIV-1 drugs suppress viral replication and maintain viral levels below the detection threshold of most assays but do not eliminate cellular reservoirs. As a result, very low levels of circulating virus can be detected in most people despite long-term treatment with potent anti-HIV drug combinations. Not surprisingly, viral levels rebound with discontinuation of treatment. New evidence indicates that there is a viral reservoir in bone marrow progenitor cells.
文摘To search for the protective actions of blumea flavanones (BFs) on hepatocytes and hepatic subcellular organelle against lipid peroxidation, monkey′s hepatocytes were isolated and cultured with or without blumea flavanones, then damaged by FeSO 4 cysteine or CCl 4. The lipid peroxidation (malondialdehyde production) and alteration in hepatocyte membrane (leakage of GPT) were estimated. Hepatic subcellular organelles were also isolated and incubated with or without blumea flavanones, then injured by FeSO 4 ascorbate. The generation of malondialdehyde(MDA) was measured. It was found that BFs 10 and 100 μmol·L 1 inhibited the MDA generation and GPT (glutamic pyruvic transaminase) leakage out of hepatocytes that were induced by CCl 4 or FeSO 4 cysteine. BFs could prevent lipid peroxidation initiated by FeSO 4 ascorbate in subcellular organelle suspension. Among BFs, BF 2 possessed the strongest activity. Conclusion: Blumea flavanones possess antioxidation activities that protect monkey′s hepatocytes and hepatic subcellular organelle against injuries induced by FeSO4 or CCl 4.
基金Chinese Ministry of Science and Technology 973 program grant awarded to Paul Zhou(2006CB504308).
文摘Neutralizing antibodies are recognized to be one of the essential elements of the adaptive immune response that must be induced by an effective vaccine against HIV. However, only a limited number of antibodies have been identified to neutralize a broad range of primary isolates of HIV-1 and attempts to induce such antibodies by inununization were unsuccessful. The difficulties to generate such antibodies are mainly due to intrinsic properties of HIV-1 envelope spikes, such as high sequence diversity, heavy glycosylation, and inducible and transient nature of certain epitopes. In vitro neutralizing antibodies are identified using "conventional" neutralization assay which uses phytohemagglutinin (PHA)-stimulated human PBMCs as target cells. Thus, in essence the assay evaluates HIV-1 replication in CD4^+T cells. Recently, several laboratories including us demonstrated that some monoclonal antibodies and HIV-1-specific polyclonal IgG purified from patient sera, although they do not have neutralizing activity when tested by the "conventional" neutralization assay, do exhibit potent and broad neutralizing activity in "unconventional" ways. The neutralizing activity of these antibodies and IgG fractions is acquired through post-translational modifications, through opsonization of virus particles into macrophages and inunature dendritic cells (iDCs), or through expression of antibodies on the surface of HIV-1-susceptible cells. This review will focus on recent findings of this area and point out their potential applications in the development of preventive strategies against HIV.
文摘The synergetic cytocidal effect of ascorbic acid and mitomycin C on Ehrlich as-cites tumor cells in culture was studied. The chain scission of DNA by Cu(Ⅱ)mitomycin C/ascorbic acid system,and the chemical kinetics of the Cu(Ⅱ) catalyzed aerobic oxidation of ascorbic acid in the presence of mitomycin C were also discussed. Experimental results showed that ascorbic acid and mitomycin C were synergetic in destroying Ehrlich ascites tumor cells.The effect is related to the breaking action of the Cu(Ⅱ)mitomycin C/ascorbic acid system on the DNA chain, and to the quantity of the system produced ·OH, and the speed of production which are both directly proportional to the concentration of ascorbic aci.These results imply that the ·OH produced in the aerobic oxidation of ascorbic acid,and·OH induced scission of DNA chain, are important factors to he synergetic cytocidal effect of ascorbic acid and mitomycin C on Ehrlich ascites tumor cells.
文摘HIV/AIDS is one of the most serious public health challenges globally. Despite the great efforts that are being devoted to prevent,treat and to better understand the disease,it is one of the main causes of morbidity and mortality worldwide. Currently,there are 30 drugs or combinations of drugs approved by FDA. Because of the side-effects,price and drug resistance,it is essential to discover new targets,to develop new technology and to find new anti-HIV drugs. This review summarizes the major targets and assays currently used in anti-HIV drug screening.
文摘Squamous cell carcinoma of the anus (SCCA) is a com- mon cancer in the human immunodeficiency virus (HIV)- infected population, and its incidence continues to in- crease in male homosexuals. Combined chemoradiation with mitomycin C and 5-fiuorouracil was poorly tolerated by severely immunocompromised patients in the early 1990s. In the era of highly active antiretroviral therapy (HAART), however, recent data indicate that: (1) most HIV patients with anal cancer can tolerate standard chemotherapy regimens; and (2) this approach is associ- ated with survival rates similar to those of HIV-negative patients. However, HIV-positive patients with SCCA are much younger, more likely to develop local tumor recur- rence, and ultimately die from anal cancer than immune competent patients. Taken together, these findings suggest that anal cancer is an often fatal neoplasia in mid- dle-aged HIV-positive male homosexuals. In this popula- tion, SCCA is an opportunistic disease resulting in patients with suboptimal immune function from persistent infection and prolonged exposition to oncogenic human papillomaviruses (HPVs). Large-scale cancer-prevention strategies (routine anuscopy and anal papanicolaou test- ing) should be implemented in this population. In addi- tion, definitive eradication of oncogenic HPVs within the anogenital mucosa of high-risk individuals might require a proactive approach with repeated vaccination.
基金Indo-Swiss Joint research Program (ISJRP)#17/2011
文摘Many plants contain ribosome inactivating proteins (RIPs) with N-glycosidase activity, which depurinate large ribosomal RNA and arrest protein synthesis. RIPs so far tested inhibit replication of mRNA as well as DNA viruses and these proteins, isolated from plants, are found to be effective against a broad range of viruses such as human immunodeficiency virus (HIV), hepatitis B virus (HBV) and herpes simplex virus (HSV). Most of the research work related to RIPs has been focused on antiviral activity against HIV; however, the exact mechanism of antiviral activity is still not clear. The mechanism of antiviral activity was thought to follow inactivation of the host cell ribosome, leading to inhibition of viral protein translation and host cell death. Enzymatic activity of RIPs is not limited to depurination of the large rRNA, in addition they can depurinate viral DNA as well as RNA. Recently, Phase I/II clinical trials have demonstrated the potential use of RIPs for treating patients with HIV disease. The aim of this review is to focus on various RIPs from plants associated with anti-HIV activity.
文摘Objective: To construct bicistronic expression vector with RANTES and SDF-1 genes, the ligands of HIV-1 principal coreceptors, and identify its expression. Methods: RANTES-KDEL was amplified from plasmid pCMV-R-K by PCR and cloned into eukaryotic expression vector pCMV-S/K. Gene transfection into HeLa cells was carried out by lipofectin. Indirect immumofluorescence and radioimmunoprecipitation were used to confirm the expression of RANTES and SDF-1. Results: The construction of pCMV-R-K-S-K was confirmed by enzymatic digestion and sequencing. RANTES and SDF-1 were shown expressed in HeLa cells by indirect immumofluorescence and radioimmunoprecipitation. Conclusion: pCMV-R-K-S-K was constructed and expressed in cell line Hela successfully, which will contribute to further study of gene therapy of AIDS by HIV-1 coreceptors knockout.
文摘AIM: To analyze the influence of human immunodeficiency virus (HIV) infection on the course of hepatitis C virus (HCV) infection. METHODS: We performed a meta-analysis to quantify the effect of HIV co-infection on progressive liver disease in patients with HCV infection. Published studies in the English or Chinese-language medical literature involving cohorts of HIV-negative and -positive patients coinfected with HCV were obtained by searching the PUBMED, EMBASE and CBM. Data were extracted independently from relevant studies by 2 investigators and used in a fixed-effect meta analysis to determine the difference in the course of HCV infection in the 2 groups. RESULTS: Twenty-nine trails involving 16 750 patients were identified including the outcome of histological fibrosis or cirrhosis or de-compensated liver disease or hepatocellular carcinoma or death. These studies yielded a combined adjusted odds ratio (OR) of 3.40 [95% confidence interval (CI) = 2.45 and 4.73]. Of note, studies that examined histological fibrosis/ cirrhosis, decompensated liver disease, hepatocellular carcinoma or death had a pooled OR of 1.47 (95% CI = 1.27 and 1.70), 5.45 (95% CI = 2.54 and 11.71), 0.76 (95% CI = 0.50 and 1.14), and 3.60 (95% CI = 3.12 and 4.15), respectively. CONCLUSION: Without highly active antiretroviral therapies (HAART), HIV accelerates HCV diseaseprogression, including death, histological fibrosis/ cirrhosis and decompensated liver disease. However, the rate of hepatocellular carcinoma is similar in persons who had HCV infection and were positive for HIV or negative for HIV.
基金National High Technology Research and Development Program of China(2005AAZ18040)
文摘The need for an efficacious HIV/AIDS vaccine remains the highest priority of the world HIV/AIDS agenda. The generation of an efficacious HIV/AIDS vaccine proves an enormous scientific challenge. This article reviews the neutralizing antibody problem,elusive immune protection,im-munogen design,pre-existing anti-vector immunity and design of phase 3 vaccine trials and the challenges and opportunities in development of HIV/AIDS vaccine are discussed.