Purpose of review Within the last two decades several members of the Coronaviridae family namely ... more Purpose of review Within the last two decades several members of the Coronaviridae family namely Severe Respiratory Syndrome (SARS-CoV) and Middle East Respiratory Syndrome (MERS-CoV) have demonstrated epidemic potential. In late, 2019 an unnamed genetic relative, later named SARS-CoV-2 realized its potential in the highly populous neighborhoods of Wuhan, China. Unchecked, the virus rapidly spread among interconnected communities and related households before containment measures could be in acted. "Appropriate" diagnostic testing in response to the SARS-CoV-2 outbreak should be urgently considered. This perspective review gives particular attention to the potential diagnostic testing of the virus in semen and seminal fluids due to its high levels of angiotensin converting enzyme 2 (ACE2) precursor. Recent findings As many infectious viruses are stable in semen and have transmitted the respective diseases, the presence of SARS-CoV-2 should be tested in semen to assess their stabilities and half-life. As in case of Ebola virus, it was present in semen for longer period in a carrier man without any symptom. Additional hypothesis is that since ACE2 could serve as a mediator for the endocytosis of the previously SARS coronavirus, SARS-CoV-2 may enter the cells through similar mechanism. From the protein expression atlas, high levels of ACE2 precursor were found in intestines and testis. Hence, the testis and seminal fluids could be the host cell and/or reservoir. The results could be used as a suggestive guideline for the sexual activities after the discharge or declaration of disease free.
Shiga toxin-producing Escherichia coli O157:H7 (E. coli O157:H7) strains are foodborne infectious... more Shiga toxin-producing Escherichia coli O157:H7 (E. coli O157:H7) strains are foodborne infectious agents that cause a number of life-threatening diseases, including hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS). Shiga toxin 1 (stx1), shiga toxin 2 (stx2), or a combination of both are responsible for most clinical symptoms of these diseases. Hence, various diagnostic methods have been developed so far to detect shiga toxins such as cell culture, ELISA, Rapid Latex Agglutination (RPLA) and hybridization, but due to high costs and labor time in addition to low sensitivity, they have not received much attention. The aim of this study was to develop a complete, rapid and reliable multiplex PCR (mPCR) method by using two pairs of specific primers to detect either the stx1 or the stx2 gene confirms the presence of E.coli O157:H7. The study results show that stx1F/stx1R primers are specific for stx1 and primers stx2F/stx2R are specific for stx2 genes in E. coli O157:H7. The mPCR method with two pairs of primers for amplifying the stx1, stx2 target genes to detect E. coli O157:H7 in food has been set up successfully. Complete method performed well in both types of food matrices with a detection limit of 3 CFU/25 g or ml of food samples. Tests on 180 food samples have shown a specificity value of 93.75% (95% confidence interval [CI], 82.83 to 100), a sensitivity of 100% (95% CI, 83.79 to 99.85%), and an accuracy of 96.66% (CI 95%, 83.41 to 99.91%). Interestingly, results indicate that the mPCR performed as well as the traditional culture methods and can reduce the diagnosis time to 2 days. Finally, complete mPCR method was applied to natural samples covering a wide variety of food types proving that the mPCR method was a rapid and reliable screening method for detection of E. coli O157:H7 in food and environmental samples.
Recently, polymorphisms in the clusterin (CLU) or Apolipoprotein J (ApoJ) gene were reported to b... more Recently, polymorphisms in the clusterin (CLU) or Apolipoprotein J (ApoJ) gene were reported to be involved in lipid metabolism, atherogenesis, and being associated with the risk of developing Alzheimer’s disease (AD). The influences from genetic variation has not been examined among Koreans. To screen genes with abnormal exon expression profiles, we developed PCR primer pairs for CLU gene. The new primer set can target specific regions of previously sequenced CLU gene. Primers were designed to target eight exon amplicons with flanking regions to optimize PCR amplification. One-hundred samples from clinically diagnosed Korean AD patients were selected for testing. We identified four single nucleotide polymorphisms (SNPs) in CLU through direct sequencing of the PCR products. These included three SNPs (rs7982, rs2279590 and rs3216167) that were previously reported variants in the SNP database (dbSNP), which could be found in NCBI. Interestingly, one new (NEW1) or extremely low-frequency mutation was found in more than one individual among the late-onset AD subjects. Our study suggests that CLU variants may also be an AD susceptibility factor among Koreans. Moreover, the findings of the study can be able to develop for simultaneous identify all of the genotypes of CLU mutation sites by DNA microarray PCR-based in the future.
Antiviral treatment of patients with active chronic hepatitis B may lead to significant reduction... more Antiviral treatment of patients with active chronic hepatitis B may lead to significant reduction in morbidity and mortality. However, after stopping nucleoside therapy, relapse rates are high in those without acquired specific immunity. We have treated two chronic hepatitis B patients with in vivo immunization. In vivo immunization aims to optimize conditions for an effective immune response: following rapid and profound virus suppression by interferon-lamivudine combination therapy, lamivudine is withdrawn intermittently for 4 weeks during continued interferon therapy. In both patients with profound virus suppression a rapid rebound in viral replication was observed after lamivudine withdrawal; despite continued interferon. These periods of renewed viral replication were followed by rises in hepatitis activity. After re-introduction of lamivudine HBV DNA became undetectable by PCR followed by normalization of serum ALT. These observations are a stimulus to further explore the concept of in vivo immunization as a novel therapeutic approach for chronic hepatitis B.
With the introduction of HAART, the HIV-1 has turned from a lethal into a chronic infection in th... more With the introduction of HAART, the HIV-1 has turned from a lethal into a chronic infection in the majority of patients. In homosexual populations, 20% of HIV-1 infected patients suffer from a chronic HBV infection, which may eventually lead to complications of the liver disease because of prolonged survival. Lamivudine is effective in reducing both HIV-1 and HBV viral replication. However, resistance for lamivudine may complicate the course of the HBV disease in HIV-1-infected patients. We, therefore, conducted a retrospective study in HIV-1-HBV co-infected patients on lamivudine therapy. All HIV-1-HBV co-infected patients who were treated with lamivudine for over 6 months in five major referral clinics in The Netherlands with HBV DNA above 2.0 x 10(5) geq ml(-1) at baseline, were evaluated. Retrospectively, the course of HBV DNA in available serum samples was established. If HBV DNA was detectable with the sensitive PCR-assay, YMDD-analyses of the polymerase gene of the hepatitis B virus was executed with the INNO-LiPA-DR-strip. Forty-six patients were evaluated. The median level of HBV DNA at start of lamivudine therapy was 1.31 x 10(9) geq ml(-1) (range 3.5 x 10(5) - 2.0 x 10(10), n=43). Of three patients no baseline sample was available, but since HBV DNA was still above 2.0 x 10(5) geq ml(-1) at week 3, 7 and 11, these patients were included. Median duration of lamivudine therapy was 97 weeks (range 27-263). The percentage of detected mutations was 25 and 52% at 1 and 2 years, respectively. Twenty-two patients ultimately developed a mutation. Both baseline Body Mass Index (BMI) and the decrease in CD4 cell count as a time dependent factor were significantly related to the emergence of mutations. In 10 out of 12 evaluated patients, HBV DNA levels returned to baseline level or even above baseline level after the development of mutant virus. One patient (5%) developed a flare of serum transaminases (ALT>10 x ULN) 24 weeks after first detection of variant virus. There is a linear time-dependent appearance of HBV mutations for lamivudine in our population. In a minority of patients (5%), development of a mutation was followed by a significant elevation of serum transaminases. A decline in CD4 cell count, which may indicate less response to HAART, induces a faster emergence of mutations and close surveillance of HBV co-infected patients on therapy may be indicated due to the prolonged survival of HIV-1 patients.
European Journal of Gastroenterology & Hepatology, 1998
Results: Clinically, the patient was in excellent condition until the development of acute hepati... more Results: Clinically, the patient was in excellent condition until the development of acute hepatitis during the lamivudine therapy period, 765 days post-OLT. Until this terminal event, serum transaminase activity was only 12 times the upper limit of normal with serum bilirubin and prothrombin ...
Cytotoxic T lymphocytes (CTL) and Kupffer cells play an important role in the immune control of h... more Cytotoxic T lymphocytes (CTL) and Kupffer cells play an important role in the immune control of hepatitis B virus (HBV), but may also induce liver injury during infection. We investigated the intrahepatic immune response in liver biopsies of chronic HBV patients in relation to inflammatory liver injury and viral control. Forty-seven liver biopsies from patients with chronic HBV with varying degrees of inflammation (ALT values) were selected. Acute hepatitis and normal liver specimens served as controls. Immune effector cells, cytotoxic effector molecules and cytokine producing cells were quantified after immunohistochemical staining in lobular and portal areas of the biopsies. The intralobular number of CD8+ T-lymphocytes was significantly decreased in biopsies of patients with high ALT (r ¼ )0.54; P < 0.001). Higher ALT-values were correlated with increased numbers of granzyme+ cells in portal areas (r ¼ 0.65; P < 0.001) and higher numbers of intralobular Fas-L+ cells (r ¼ 0.32; P ¼ 0.05). Fas-L was expressed on Kupffer and lymphoid cells. More intralobular CD8+ T-lymphocytes were found in HBeAg) than in HBeAg+ patients (P ¼ 0.002). But IFN-c and TNF-a producing cells were observed sporadically in chronic HBV patients. Hence, in chronic HBV infection, low viral replication and HBeAg negativity is related to increased presence of intralobular CD8+ T-lymphocytes. Persistence of the virus may be caused by the absence of cells producing anti-viral cytokines in the liver. Inflammatory liver injury during chronic HBV infection is probably not the result of increased numbers of infiltrating CD8+ T-lymphocytes, but of Fas-L expression by Kupffer cells and increased cytolytic activity of cells in portal areas.
Vertical transmission of hepatitis B virus (HBV) can occur occasionally despite vaccination of th... more Vertical transmission of hepatitis B virus (HBV) can occur occasionally despite vaccination of the child. This vaccination breakthrough has been associated with high maternal viraemia. We treated eight highly viraemic (HBV-DNA ‡ 1.2 · 10 9 geq/mL) mothers with 150 mg of lamivudine daily during the last month of pregnancy. HBV-DNA, hepatitis B surface antigen (HBsAg), anti-HBs and anti-HBc of their offspring were measured at birth and at 3, 6 and 12 months, respectively. Twenty-four children, born to untreated HBsAg-positive mothers with HBV-DNA levels ‡1.2 · 10 9 geq/mL served as historical controls. All children received passive-active immunization at birth and were followed-up for 12 months. In the lamivudine group one of the eight children (12.5%) was still HBsAg and HBV-DNA positive at the age of 12 months. All other children seroconverted to anti-HBs and maintained seroprotection. In three children, HBV-DNA was temporarily detected by polymerase chain reaction. In the untreated historical control group, perinatal transmission occurred in seven of 25 children (28%). In highly viraemic HBsAgpositive mothers, reduction of viraemia by lamivudine therapy in the last month of pregnancy may be an effective and safe measure to reduce the risk of child vaccination breakthrough. This approach should be evaluated in a large controlled trial.
Characteristics of the intrahepatic virus-specific T-cell response in patients with acute hepatit... more Characteristics of the intrahepatic virus-specific T-cell response in patients with acute hepatitis B virus (HBV) infection have not been studied due to the risk of complications associated with standard liver biopsies. In this study we aimed to characterize the virus-specific CD8 + T-cell response in the liver of patients with acute HBV infection using fine-needle aspiration-biopsy (FNAB). In HLA-A2 positive patients with acute HBV infection a FNAB was performed at first presentation, at the time of HBsAg-seroconversion and 3 months after HBsAg-seroconversion. HLA-A2 tetramers were used to identify HBV-specific CD8 + T-cells in FNAB-cytology and peripheral blood (PB). At first presentation there was a correlation between the frequency of intrahepatic CD8 + T-cells and the degree of liver damage. At all time points there was sequestering of HBV-specific CD8 + T-cells in the liver, and the percentage of intrahepatic HLA-DR expressing HBV-specific CD8 + T-cells was higher than in PB. Three months after HBsAg-seroconversion the frequency of intrahepatic HBV-specific CD8 + T-cells remained high. HBV-specific CD8 + T-cells are compartmentalized in the liver during acute HBV infection. Their presence in the liver may suggest a role in the resolution of the infection. Intrahepatic HBV-specific CD8 + T cells remain detectable at high frequencies after HBsAg-seroconversion.
Only in a minority of patients with chronic hepatitis B (CHB) will treatment with interferon (IFN... more Only in a minority of patients with chronic hepatitis B (CHB) will treatment with interferon (IFN)-alpha or nucleoside analogues lead to sustained virological response. In vivo immunization (IVI) following virus suppression aims to optimize conditions for an effective immune response: following rapid and profound virus suppression by interferon-lamivudine combination therapy, lamivudine is withdrawn intermittently during continued interferon therapy. It is thought that withdrawal of lamivudine will lead to increased viral replication and increased antigen expression with subsequent immune stimulation. The aim of this prospective pilot study was to evaluate IVI as a therapeutic approach for CHB. Fourteen HBeAg-positive CHB patients were treated for 42 weeks with a combination of pegylated interferon-alpha 2b and lamivudine. After 12 weeks of combination therapy lamivudine was withdrawn intermittently for three consecutive periods of 4 weeks until it was permanently stopped on week 36. At the end of follow-up (week 52) all patients had remained HBeAg positive and the median viral load was similar to baseline. During the initial 12 weeks of treatment, there was a reduction of both the hepatitis B virus (HBV)-specific proliferation capacity of Th-cells and the frequencies of IFNgamma-producing cells. During the lamivudine interruption-cycle there was an inverse relation between the increase of HBV-DNA, and the decrease in proliferation capacity and frequency of IFN-gamma-producing cells. The intrahepatic fraction of CD8(+) T-cells increased during lamivudine withdrawal. In conclusion, IVI was able to transiently stimulate the HBV-specific immune responsiveness of T-cells, but the magnitude of the response was insufficient to cause a beneficial virological effect.
Several types of neurodegenerative diseases were described, including Alzheimer’s disease (AD), f... more Several types of neurodegenerative diseases were described, including Alzheimer’s disease (AD), frontotemporal dementia (FTD), amyotrophic lateral sclerosis (ALS), prion disease, and Parkinson’s disease (PD). Since the potential treatment strategies of these disorders might be more successful in the pre-clinical stages than in the actual clinical setup, new diagnostic methods were needed. The involvement of heredity in neurodegenerative disorders was established, but several neurodegenerative disorders such as AD, PD, ALS, FTD and Huntington’s disease (HD) are highly complex. Sanger sequencing was used to detect mutations that are causative or risk factors for diseases. The problem with standard sequencing is its high cost and low speed. Recently, next generation sequencing (NGS) strategies were developed, which could provide a more complex genetic analysis of patients with neurodegenerative diseases. In this study, 50 genes were selected, which were established as causative genes for neurodegenerative diseases, but we also included several risk factor genes and candidate genes. Primers (maximum 400-bp length) were designed to screen for mutations and variants in them. We plan to use these primers for NGS screening to create a more detailed genetic profile for these patients. This study could enhance disease diagnosis and would be also helpful in estimating the risk for disease onset in the future.
Apolipoprotein E (APOE) is a lipid-transport protein abundantly expressed in most neurons in the ... more Apolipoprotein E (APOE) is a lipid-transport protein abundantly expressed in most neurons in the central nervous system. APOE-dependent alterations of the endocytic pathway can affect different functions. APOE binds to cell-surface receptors to deliver lipids and to the hydrophobic amyloid-β peptide, regulating amyloid-β aggregations and clearances in the brain. Several APOE isoforms with major structural differences were discovered and shown to influence the brain lipid transport, glucose metabolism, neuronal signaling, neuroinflammation, and mitochondrial function. This review will summarize the updated research progress on APOE functions and its role in Alzheimer’s disease, Parkinson’s disease, cardiovascular diseases, multiple sclerosis, type 2 diabetes mellitus, Type III hyperlipoproteinemia, vascular dementia, and ischemic stroke. Understanding the mutations in APOE, their structural properties, and their isoforms is important to determine its role in various diseases and to advance the development of therapeutic strategies. Targeting APOE may be a potential approach for diagnosis, risk assessment, prevention, and treatment of various neurodegenerative and cardiovascular diseases in humans.
SUMMARY:
The objective of this study was developing the multiplex PCR method using two pairs of ... more SUMMARY:
The objective of this study was developing the multiplex PCR method using two pairs of specific primers to detect E.coli O157 in food. The study results show that stx1F/stx1R primer sare specific for stx1 and primers stx2F/stx2R are specific for stx2 genes in E.coli O157. The multiplex PCR method with two pairs of primers for amplifying the stx1, stx2 target genes to detect E. coli O157 in food has been set up successfully. The results of evaluating of method show that the multiplex PCR method have sensitivityis 98%, accuracy is 98%, specificity is 100%, the false positive rate is 0% and false negative rate is 4%. The above results indicate the multiplex PCR has been set up and the standard method according to ISO16654:2001 are equivalent for detection of E. coli O157 in food, but the time for analysis of multiplex PCR is shorter,only 2 days.
ABSTRACT: The ethyl acetate fraction (Et-F) of Polygonum tomentosum Willd was separated by silica... more ABSTRACT: The ethyl acetate fraction (Et-F) of Polygonum tomentosum Willd was separated by silica gel vacuum chromatography to give 11 subfractions (PTE1-PTE11). The antioxidative activity of subfractions was determined by qualitative assay by TLC assays. The result of qualitative assay showed that all 11 subfractions had antioxidative activity. The results of ex vivo hepatoprotection of 11subfractions showed that PTE7, PTE8 and PTE9 had higher ex vivo hepatoprotective activities than those of the other subfractions. PTE8 was further studied by silica gel chromatography to obtain A1compound, which was identified as quercitrin. (To the best of our knowledge) This is the first report on the occurrence of quercitrin in P. tomentosum. Quercitrin had signifying both ex vivo and in vivo hepatoprotective effects on injury liver mice induced by carbon tetracloride (CCl4). The results in the present study indicated that P. tomentosum is a potential source of natural hepatoprotection
Introduction: Houttuynia cordata Thunb. is a medicinal herb that generally be used in Vietnamese ... more Introduction: Houttuynia cordata Thunb. is a medicinal herb that generally be used in Vietnamese traditional medicine. Many studies have shown that flavonoids exhibited a wide range of biological or physiological effects including anti-inflammatory, anti-allergic, and anti-cancer activities. However, no reports to be discussed about the relationship between the levels of H. cordata flavonoids and its biological characteristics.
Method: In our present study, the hepatoprotective activities of the Houttuynia cordata extracts with different solvents were performed on carbon tetrachloride (CCl4) induced cytotoxicity model modified by Kiso procedure. Suspension of isolated mouse hepatocytes was incubated in EMEM medium under a 95% O2 and 5% CO2, 37oC in 2h before the addition of 1.5% CCl4 and incubated in 45 min. CCl4 administration significantly.
increased serum alanine aminotransferase (ALT) activity, a biochemical marker of hepatocyte injury, in medium.
Results: The methanol extract of Houttuynia cordata have reduced the level of ALT and protected mice liver cells at a concentration of 0.05 mg/ml.
Conclusion: the methanol extract of Houttuynia cordata have reduced the level of ALT and protected mice liver cells.
ABSTRACT: Orthosiphon aristatus Blume, a member of the Lamiaceac family, is a medicinal herb kno... more ABSTRACT: Orthosiphon aristatus Blume, a member of the Lamiaceac family, is a medicinal herb known useful as a diuretic agent, used popularly in Vietnam and the nations in the world. In our previous research, it is found that O. aristatus had strong antioxidant in both methods of the ferric reducing/antioxidant power assay and the 1,1-diphenyl-2-picryl-hydrazyl free radical scavenging assay. The purpose of the present study was to examine the methanolic extract of O. aristatus with strong antioxidative activity against carbon tetrachloride (CCl4) induced cytotoxicity in isolated mouse hepatocytes using a modified procedure of Kiso. Suspension of isolated mouse hepatocytes incubated in E’MEM medium under a gas 95% O2 and 5% CO2, 37oC in 2h before the addition of 1.5% CCl4 and incubated in 45’. CCl4 administration significantly increased serum alanine aminotransferase (ALT) activity, a biochemical marker of hepatocyte injury in medium. Pretreatment with different concentration of methanolic extract of O. aristatus reduced ALT level. Methanolic extract with concentration of 0.1 và 0.25 mg/ml, were decreased ALT activity 60% compared to toxic group, remaining of the serum ALT was 104% compared to control group. The results of the present study showed that strong antioxidative activity of methanolic extract plays a crucial role in providing protection against such hepatocyte damage, and also supported the traditional believes on hepatoprotective effect of O. aristatus extract.
Keywords: Hepatocytes, Orthosiphon aristatus, CCl4, hepatoprotective effect
Purpose of review Within the last two decades several members of the Coronaviridae family namely ... more Purpose of review Within the last two decades several members of the Coronaviridae family namely Severe Respiratory Syndrome (SARS-CoV) and Middle East Respiratory Syndrome (MERS-CoV) have demonstrated epidemic potential. In late, 2019 an unnamed genetic relative, later named SARS-CoV-2 realized its potential in the highly populous neighborhoods of Wuhan, China. Unchecked, the virus rapidly spread among interconnected communities and related households before containment measures could be in acted. "Appropriate" diagnostic testing in response to the SARS-CoV-2 outbreak should be urgently considered. This perspective review gives particular attention to the potential diagnostic testing of the virus in semen and seminal fluids due to its high levels of angiotensin converting enzyme 2 (ACE2) precursor. Recent findings As many infectious viruses are stable in semen and have transmitted the respective diseases, the presence of SARS-CoV-2 should be tested in semen to assess their stabilities and half-life. As in case of Ebola virus, it was present in semen for longer period in a carrier man without any symptom. Additional hypothesis is that since ACE2 could serve as a mediator for the endocytosis of the previously SARS coronavirus, SARS-CoV-2 may enter the cells through similar mechanism. From the protein expression atlas, high levels of ACE2 precursor were found in intestines and testis. Hence, the testis and seminal fluids could be the host cell and/or reservoir. The results could be used as a suggestive guideline for the sexual activities after the discharge or declaration of disease free.
Shiga toxin-producing Escherichia coli O157:H7 (E. coli O157:H7) strains are foodborne infectious... more Shiga toxin-producing Escherichia coli O157:H7 (E. coli O157:H7) strains are foodborne infectious agents that cause a number of life-threatening diseases, including hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS). Shiga toxin 1 (stx1), shiga toxin 2 (stx2), or a combination of both are responsible for most clinical symptoms of these diseases. Hence, various diagnostic methods have been developed so far to detect shiga toxins such as cell culture, ELISA, Rapid Latex Agglutination (RPLA) and hybridization, but due to high costs and labor time in addition to low sensitivity, they have not received much attention. The aim of this study was to develop a complete, rapid and reliable multiplex PCR (mPCR) method by using two pairs of specific primers to detect either the stx1 or the stx2 gene confirms the presence of E.coli O157:H7. The study results show that stx1F/stx1R primers are specific for stx1 and primers stx2F/stx2R are specific for stx2 genes in E. coli O157:H7. The mPCR method with two pairs of primers for amplifying the stx1, stx2 target genes to detect E. coli O157:H7 in food has been set up successfully. Complete method performed well in both types of food matrices with a detection limit of 3 CFU/25 g or ml of food samples. Tests on 180 food samples have shown a specificity value of 93.75% (95% confidence interval [CI], 82.83 to 100), a sensitivity of 100% (95% CI, 83.79 to 99.85%), and an accuracy of 96.66% (CI 95%, 83.41 to 99.91%). Interestingly, results indicate that the mPCR performed as well as the traditional culture methods and can reduce the diagnosis time to 2 days. Finally, complete mPCR method was applied to natural samples covering a wide variety of food types proving that the mPCR method was a rapid and reliable screening method for detection of E. coli O157:H7 in food and environmental samples.
Recently, polymorphisms in the clusterin (CLU) or Apolipoprotein J (ApoJ) gene were reported to b... more Recently, polymorphisms in the clusterin (CLU) or Apolipoprotein J (ApoJ) gene were reported to be involved in lipid metabolism, atherogenesis, and being associated with the risk of developing Alzheimer’s disease (AD). The influences from genetic variation has not been examined among Koreans. To screen genes with abnormal exon expression profiles, we developed PCR primer pairs for CLU gene. The new primer set can target specific regions of previously sequenced CLU gene. Primers were designed to target eight exon amplicons with flanking regions to optimize PCR amplification. One-hundred samples from clinically diagnosed Korean AD patients were selected for testing. We identified four single nucleotide polymorphisms (SNPs) in CLU through direct sequencing of the PCR products. These included three SNPs (rs7982, rs2279590 and rs3216167) that were previously reported variants in the SNP database (dbSNP), which could be found in NCBI. Interestingly, one new (NEW1) or extremely low-frequency mutation was found in more than one individual among the late-onset AD subjects. Our study suggests that CLU variants may also be an AD susceptibility factor among Koreans. Moreover, the findings of the study can be able to develop for simultaneous identify all of the genotypes of CLU mutation sites by DNA microarray PCR-based in the future.
Antiviral treatment of patients with active chronic hepatitis B may lead to significant reduction... more Antiviral treatment of patients with active chronic hepatitis B may lead to significant reduction in morbidity and mortality. However, after stopping nucleoside therapy, relapse rates are high in those without acquired specific immunity. We have treated two chronic hepatitis B patients with in vivo immunization. In vivo immunization aims to optimize conditions for an effective immune response: following rapid and profound virus suppression by interferon-lamivudine combination therapy, lamivudine is withdrawn intermittently for 4 weeks during continued interferon therapy. In both patients with profound virus suppression a rapid rebound in viral replication was observed after lamivudine withdrawal; despite continued interferon. These periods of renewed viral replication were followed by rises in hepatitis activity. After re-introduction of lamivudine HBV DNA became undetectable by PCR followed by normalization of serum ALT. These observations are a stimulus to further explore the concept of in vivo immunization as a novel therapeutic approach for chronic hepatitis B.
With the introduction of HAART, the HIV-1 has turned from a lethal into a chronic infection in th... more With the introduction of HAART, the HIV-1 has turned from a lethal into a chronic infection in the majority of patients. In homosexual populations, 20% of HIV-1 infected patients suffer from a chronic HBV infection, which may eventually lead to complications of the liver disease because of prolonged survival. Lamivudine is effective in reducing both HIV-1 and HBV viral replication. However, resistance for lamivudine may complicate the course of the HBV disease in HIV-1-infected patients. We, therefore, conducted a retrospective study in HIV-1-HBV co-infected patients on lamivudine therapy. All HIV-1-HBV co-infected patients who were treated with lamivudine for over 6 months in five major referral clinics in The Netherlands with HBV DNA above 2.0 x 10(5) geq ml(-1) at baseline, were evaluated. Retrospectively, the course of HBV DNA in available serum samples was established. If HBV DNA was detectable with the sensitive PCR-assay, YMDD-analyses of the polymerase gene of the hepatitis B virus was executed with the INNO-LiPA-DR-strip. Forty-six patients were evaluated. The median level of HBV DNA at start of lamivudine therapy was 1.31 x 10(9) geq ml(-1) (range 3.5 x 10(5) - 2.0 x 10(10), n=43). Of three patients no baseline sample was available, but since HBV DNA was still above 2.0 x 10(5) geq ml(-1) at week 3, 7 and 11, these patients were included. Median duration of lamivudine therapy was 97 weeks (range 27-263). The percentage of detected mutations was 25 and 52% at 1 and 2 years, respectively. Twenty-two patients ultimately developed a mutation. Both baseline Body Mass Index (BMI) and the decrease in CD4 cell count as a time dependent factor were significantly related to the emergence of mutations. In 10 out of 12 evaluated patients, HBV DNA levels returned to baseline level or even above baseline level after the development of mutant virus. One patient (5%) developed a flare of serum transaminases (ALT&gt;10 x ULN) 24 weeks after first detection of variant virus. There is a linear time-dependent appearance of HBV mutations for lamivudine in our population. In a minority of patients (5%), development of a mutation was followed by a significant elevation of serum transaminases. A decline in CD4 cell count, which may indicate less response to HAART, induces a faster emergence of mutations and close surveillance of HBV co-infected patients on therapy may be indicated due to the prolonged survival of HIV-1 patients.
European Journal of Gastroenterology & Hepatology, 1998
Results: Clinically, the patient was in excellent condition until the development of acute hepati... more Results: Clinically, the patient was in excellent condition until the development of acute hepatitis during the lamivudine therapy period, 765 days post-OLT. Until this terminal event, serum transaminase activity was only 12 times the upper limit of normal with serum bilirubin and prothrombin ...
Cytotoxic T lymphocytes (CTL) and Kupffer cells play an important role in the immune control of h... more Cytotoxic T lymphocytes (CTL) and Kupffer cells play an important role in the immune control of hepatitis B virus (HBV), but may also induce liver injury during infection. We investigated the intrahepatic immune response in liver biopsies of chronic HBV patients in relation to inflammatory liver injury and viral control. Forty-seven liver biopsies from patients with chronic HBV with varying degrees of inflammation (ALT values) were selected. Acute hepatitis and normal liver specimens served as controls. Immune effector cells, cytotoxic effector molecules and cytokine producing cells were quantified after immunohistochemical staining in lobular and portal areas of the biopsies. The intralobular number of CD8+ T-lymphocytes was significantly decreased in biopsies of patients with high ALT (r ¼ )0.54; P < 0.001). Higher ALT-values were correlated with increased numbers of granzyme+ cells in portal areas (r ¼ 0.65; P < 0.001) and higher numbers of intralobular Fas-L+ cells (r ¼ 0.32; P ¼ 0.05). Fas-L was expressed on Kupffer and lymphoid cells. More intralobular CD8+ T-lymphocytes were found in HBeAg) than in HBeAg+ patients (P ¼ 0.002). But IFN-c and TNF-a producing cells were observed sporadically in chronic HBV patients. Hence, in chronic HBV infection, low viral replication and HBeAg negativity is related to increased presence of intralobular CD8+ T-lymphocytes. Persistence of the virus may be caused by the absence of cells producing anti-viral cytokines in the liver. Inflammatory liver injury during chronic HBV infection is probably not the result of increased numbers of infiltrating CD8+ T-lymphocytes, but of Fas-L expression by Kupffer cells and increased cytolytic activity of cells in portal areas.
Vertical transmission of hepatitis B virus (HBV) can occur occasionally despite vaccination of th... more Vertical transmission of hepatitis B virus (HBV) can occur occasionally despite vaccination of the child. This vaccination breakthrough has been associated with high maternal viraemia. We treated eight highly viraemic (HBV-DNA ‡ 1.2 · 10 9 geq/mL) mothers with 150 mg of lamivudine daily during the last month of pregnancy. HBV-DNA, hepatitis B surface antigen (HBsAg), anti-HBs and anti-HBc of their offspring were measured at birth and at 3, 6 and 12 months, respectively. Twenty-four children, born to untreated HBsAg-positive mothers with HBV-DNA levels ‡1.2 · 10 9 geq/mL served as historical controls. All children received passive-active immunization at birth and were followed-up for 12 months. In the lamivudine group one of the eight children (12.5%) was still HBsAg and HBV-DNA positive at the age of 12 months. All other children seroconverted to anti-HBs and maintained seroprotection. In three children, HBV-DNA was temporarily detected by polymerase chain reaction. In the untreated historical control group, perinatal transmission occurred in seven of 25 children (28%). In highly viraemic HBsAgpositive mothers, reduction of viraemia by lamivudine therapy in the last month of pregnancy may be an effective and safe measure to reduce the risk of child vaccination breakthrough. This approach should be evaluated in a large controlled trial.
Characteristics of the intrahepatic virus-specific T-cell response in patients with acute hepatit... more Characteristics of the intrahepatic virus-specific T-cell response in patients with acute hepatitis B virus (HBV) infection have not been studied due to the risk of complications associated with standard liver biopsies. In this study we aimed to characterize the virus-specific CD8 + T-cell response in the liver of patients with acute HBV infection using fine-needle aspiration-biopsy (FNAB). In HLA-A2 positive patients with acute HBV infection a FNAB was performed at first presentation, at the time of HBsAg-seroconversion and 3 months after HBsAg-seroconversion. HLA-A2 tetramers were used to identify HBV-specific CD8 + T-cells in FNAB-cytology and peripheral blood (PB). At first presentation there was a correlation between the frequency of intrahepatic CD8 + T-cells and the degree of liver damage. At all time points there was sequestering of HBV-specific CD8 + T-cells in the liver, and the percentage of intrahepatic HLA-DR expressing HBV-specific CD8 + T-cells was higher than in PB. Three months after HBsAg-seroconversion the frequency of intrahepatic HBV-specific CD8 + T-cells remained high. HBV-specific CD8 + T-cells are compartmentalized in the liver during acute HBV infection. Their presence in the liver may suggest a role in the resolution of the infection. Intrahepatic HBV-specific CD8 + T cells remain detectable at high frequencies after HBsAg-seroconversion.
Only in a minority of patients with chronic hepatitis B (CHB) will treatment with interferon (IFN... more Only in a minority of patients with chronic hepatitis B (CHB) will treatment with interferon (IFN)-alpha or nucleoside analogues lead to sustained virological response. In vivo immunization (IVI) following virus suppression aims to optimize conditions for an effective immune response: following rapid and profound virus suppression by interferon-lamivudine combination therapy, lamivudine is withdrawn intermittently during continued interferon therapy. It is thought that withdrawal of lamivudine will lead to increased viral replication and increased antigen expression with subsequent immune stimulation. The aim of this prospective pilot study was to evaluate IVI as a therapeutic approach for CHB. Fourteen HBeAg-positive CHB patients were treated for 42 weeks with a combination of pegylated interferon-alpha 2b and lamivudine. After 12 weeks of combination therapy lamivudine was withdrawn intermittently for three consecutive periods of 4 weeks until it was permanently stopped on week 36. At the end of follow-up (week 52) all patients had remained HBeAg positive and the median viral load was similar to baseline. During the initial 12 weeks of treatment, there was a reduction of both the hepatitis B virus (HBV)-specific proliferation capacity of Th-cells and the frequencies of IFNgamma-producing cells. During the lamivudine interruption-cycle there was an inverse relation between the increase of HBV-DNA, and the decrease in proliferation capacity and frequency of IFN-gamma-producing cells. The intrahepatic fraction of CD8(+) T-cells increased during lamivudine withdrawal. In conclusion, IVI was able to transiently stimulate the HBV-specific immune responsiveness of T-cells, but the magnitude of the response was insufficient to cause a beneficial virological effect.
Several types of neurodegenerative diseases were described, including Alzheimer’s disease (AD), f... more Several types of neurodegenerative diseases were described, including Alzheimer’s disease (AD), frontotemporal dementia (FTD), amyotrophic lateral sclerosis (ALS), prion disease, and Parkinson’s disease (PD). Since the potential treatment strategies of these disorders might be more successful in the pre-clinical stages than in the actual clinical setup, new diagnostic methods were needed. The involvement of heredity in neurodegenerative disorders was established, but several neurodegenerative disorders such as AD, PD, ALS, FTD and Huntington’s disease (HD) are highly complex. Sanger sequencing was used to detect mutations that are causative or risk factors for diseases. The problem with standard sequencing is its high cost and low speed. Recently, next generation sequencing (NGS) strategies were developed, which could provide a more complex genetic analysis of patients with neurodegenerative diseases. In this study, 50 genes were selected, which were established as causative genes for neurodegenerative diseases, but we also included several risk factor genes and candidate genes. Primers (maximum 400-bp length) were designed to screen for mutations and variants in them. We plan to use these primers for NGS screening to create a more detailed genetic profile for these patients. This study could enhance disease diagnosis and would be also helpful in estimating the risk for disease onset in the future.
Apolipoprotein E (APOE) is a lipid-transport protein abundantly expressed in most neurons in the ... more Apolipoprotein E (APOE) is a lipid-transport protein abundantly expressed in most neurons in the central nervous system. APOE-dependent alterations of the endocytic pathway can affect different functions. APOE binds to cell-surface receptors to deliver lipids and to the hydrophobic amyloid-β peptide, regulating amyloid-β aggregations and clearances in the brain. Several APOE isoforms with major structural differences were discovered and shown to influence the brain lipid transport, glucose metabolism, neuronal signaling, neuroinflammation, and mitochondrial function. This review will summarize the updated research progress on APOE functions and its role in Alzheimer’s disease, Parkinson’s disease, cardiovascular diseases, multiple sclerosis, type 2 diabetes mellitus, Type III hyperlipoproteinemia, vascular dementia, and ischemic stroke. Understanding the mutations in APOE, their structural properties, and their isoforms is important to determine its role in various diseases and to advance the development of therapeutic strategies. Targeting APOE may be a potential approach for diagnosis, risk assessment, prevention, and treatment of various neurodegenerative and cardiovascular diseases in humans.
SUMMARY:
The objective of this study was developing the multiplex PCR method using two pairs of ... more SUMMARY:
The objective of this study was developing the multiplex PCR method using two pairs of specific primers to detect E.coli O157 in food. The study results show that stx1F/stx1R primer sare specific for stx1 and primers stx2F/stx2R are specific for stx2 genes in E.coli O157. The multiplex PCR method with two pairs of primers for amplifying the stx1, stx2 target genes to detect E. coli O157 in food has been set up successfully. The results of evaluating of method show that the multiplex PCR method have sensitivityis 98%, accuracy is 98%, specificity is 100%, the false positive rate is 0% and false negative rate is 4%. The above results indicate the multiplex PCR has been set up and the standard method according to ISO16654:2001 are equivalent for detection of E. coli O157 in food, but the time for analysis of multiplex PCR is shorter,only 2 days.
ABSTRACT: The ethyl acetate fraction (Et-F) of Polygonum tomentosum Willd was separated by silica... more ABSTRACT: The ethyl acetate fraction (Et-F) of Polygonum tomentosum Willd was separated by silica gel vacuum chromatography to give 11 subfractions (PTE1-PTE11). The antioxidative activity of subfractions was determined by qualitative assay by TLC assays. The result of qualitative assay showed that all 11 subfractions had antioxidative activity. The results of ex vivo hepatoprotection of 11subfractions showed that PTE7, PTE8 and PTE9 had higher ex vivo hepatoprotective activities than those of the other subfractions. PTE8 was further studied by silica gel chromatography to obtain A1compound, which was identified as quercitrin. (To the best of our knowledge) This is the first report on the occurrence of quercitrin in P. tomentosum. Quercitrin had signifying both ex vivo and in vivo hepatoprotective effects on injury liver mice induced by carbon tetracloride (CCl4). The results in the present study indicated that P. tomentosum is a potential source of natural hepatoprotection
Introduction: Houttuynia cordata Thunb. is a medicinal herb that generally be used in Vietnamese ... more Introduction: Houttuynia cordata Thunb. is a medicinal herb that generally be used in Vietnamese traditional medicine. Many studies have shown that flavonoids exhibited a wide range of biological or physiological effects including anti-inflammatory, anti-allergic, and anti-cancer activities. However, no reports to be discussed about the relationship between the levels of H. cordata flavonoids and its biological characteristics.
Method: In our present study, the hepatoprotective activities of the Houttuynia cordata extracts with different solvents were performed on carbon tetrachloride (CCl4) induced cytotoxicity model modified by Kiso procedure. Suspension of isolated mouse hepatocytes was incubated in EMEM medium under a 95% O2 and 5% CO2, 37oC in 2h before the addition of 1.5% CCl4 and incubated in 45 min. CCl4 administration significantly.
increased serum alanine aminotransferase (ALT) activity, a biochemical marker of hepatocyte injury, in medium.
Results: The methanol extract of Houttuynia cordata have reduced the level of ALT and protected mice liver cells at a concentration of 0.05 mg/ml.
Conclusion: the methanol extract of Houttuynia cordata have reduced the level of ALT and protected mice liver cells.
ABSTRACT: Orthosiphon aristatus Blume, a member of the Lamiaceac family, is a medicinal herb kno... more ABSTRACT: Orthosiphon aristatus Blume, a member of the Lamiaceac family, is a medicinal herb known useful as a diuretic agent, used popularly in Vietnam and the nations in the world. In our previous research, it is found that O. aristatus had strong antioxidant in both methods of the ferric reducing/antioxidant power assay and the 1,1-diphenyl-2-picryl-hydrazyl free radical scavenging assay. The purpose of the present study was to examine the methanolic extract of O. aristatus with strong antioxidative activity against carbon tetrachloride (CCl4) induced cytotoxicity in isolated mouse hepatocytes using a modified procedure of Kiso. Suspension of isolated mouse hepatocytes incubated in E’MEM medium under a gas 95% O2 and 5% CO2, 37oC in 2h before the addition of 1.5% CCl4 and incubated in 45’. CCl4 administration significantly increased serum alanine aminotransferase (ALT) activity, a biochemical marker of hepatocyte injury in medium. Pretreatment with different concentration of methanolic extract of O. aristatus reduced ALT level. Methanolic extract with concentration of 0.1 và 0.25 mg/ml, were decreased ALT activity 60% compared to toxic group, remaining of the serum ALT was 104% compared to control group. The results of the present study showed that strong antioxidative activity of methanolic extract plays a crucial role in providing protection against such hepatocyte damage, and also supported the traditional believes on hepatoprotective effect of O. aristatus extract.
Keywords: Hepatocytes, Orthosiphon aristatus, CCl4, hepatoprotective effect
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The objective of this study was developing the multiplex PCR method using two pairs of specific primers to detect E.coli O157 in food. The study results show that stx1F/stx1R primer sare specific for stx1 and primers stx2F/stx2R are specific for stx2 genes in E.coli O157. The multiplex PCR method with two pairs of primers for amplifying the stx1, stx2 target genes to detect E. coli O157 in food has been set up successfully. The results of evaluating of method show that the multiplex PCR method have sensitivityis 98%, accuracy is 98%, specificity is 100%, the false positive rate is 0% and false negative rate is 4%. The above results indicate the multiplex PCR has been set up and the standard method according to ISO16654:2001 are equivalent for detection of E. coli O157 in food, but the time for analysis of multiplex PCR is shorter,only 2 days.
Keywords: Polygonum tomentosum, antioxidative activity, DPPH, CCl4, hepatoprotective effect, quercitrin.
Method: In our present study, the hepatoprotective activities of the Houttuynia cordata extracts with different solvents were performed on carbon tetrachloride (CCl4) induced cytotoxicity model modified by Kiso procedure. Suspension of isolated mouse hepatocytes was incubated in EMEM medium under a 95% O2 and 5% CO2, 37oC in 2h before the addition of 1.5% CCl4 and incubated in 45 min. CCl4 administration significantly.
increased serum alanine aminotransferase (ALT) activity, a biochemical marker of hepatocyte injury, in medium.
Results: The methanol extract of Houttuynia cordata have reduced the level of ALT and protected mice liver cells at a concentration of 0.05 mg/ml.
Conclusion: the methanol extract of Houttuynia cordata have reduced the level of ALT and protected mice liver cells.
Key words: hepatocyte, Houttuynia cordata, CCl4, hepatoprotective activity.
Keywords: Hepatocytes, Orthosiphon aristatus, CCl4, hepatoprotective effect
The objective of this study was developing the multiplex PCR method using two pairs of specific primers to detect E.coli O157 in food. The study results show that stx1F/stx1R primer sare specific for stx1 and primers stx2F/stx2R are specific for stx2 genes in E.coli O157. The multiplex PCR method with two pairs of primers for amplifying the stx1, stx2 target genes to detect E. coli O157 in food has been set up successfully. The results of evaluating of method show that the multiplex PCR method have sensitivityis 98%, accuracy is 98%, specificity is 100%, the false positive rate is 0% and false negative rate is 4%. The above results indicate the multiplex PCR has been set up and the standard method according to ISO16654:2001 are equivalent for detection of E. coli O157 in food, but the time for analysis of multiplex PCR is shorter,only 2 days.
Keywords: Polygonum tomentosum, antioxidative activity, DPPH, CCl4, hepatoprotective effect, quercitrin.
Method: In our present study, the hepatoprotective activities of the Houttuynia cordata extracts with different solvents were performed on carbon tetrachloride (CCl4) induced cytotoxicity model modified by Kiso procedure. Suspension of isolated mouse hepatocytes was incubated in EMEM medium under a 95% O2 and 5% CO2, 37oC in 2h before the addition of 1.5% CCl4 and incubated in 45 min. CCl4 administration significantly.
increased serum alanine aminotransferase (ALT) activity, a biochemical marker of hepatocyte injury, in medium.
Results: The methanol extract of Houttuynia cordata have reduced the level of ALT and protected mice liver cells at a concentration of 0.05 mg/ml.
Conclusion: the methanol extract of Houttuynia cordata have reduced the level of ALT and protected mice liver cells.
Key words: hepatocyte, Houttuynia cordata, CCl4, hepatoprotective activity.
Keywords: Hepatocytes, Orthosiphon aristatus, CCl4, hepatoprotective effect