BACKGROUND Healthcare workers (HCWs) are at increased risk of getting influenza than the general ... more BACKGROUND Healthcare workers (HCWs) are at increased risk of getting influenza than the general population, therefore putting patients at risk of nosocomial infection. Influenza vaccination coverage among HCWs is low despite the availability of a safe and effective vaccine. However, the reasons for such a poor uptake are not well reported in Malaysia. This study aimed at assessing the rate of influenza vaccination uptake, knowledge and attitude of healthcare workers regarding influenza, and employers' policy on influenza vaccination. METHODS A cross-sectional questionnaire survey was conducted in three hospitals in the Klang Valley. Mann-Whitney test was used to assess possible differences in knowledge and attitude towards flu vaccination and the χ2 was used for categorical variables. Analyses were performed with SPSS 22.0. RESULTS A total of 690 questionnaires were distributed; 527 were returned (giving a response rate of 76.4%. The vaccine uptake was 51.4% with the majority (...
Hepatitis B virus infection is a serious health problem worldwide, and more than 350 million peop... more Hepatitis B virus infection is a serious health problem worldwide, and more than 350 million people are chronic carriers, constituting a major global threat. Southeast Asia and the Western Pacific have the highest levels of endemicity in the world, with an estimated seroprevalence ranging between 2% and 31%. Mutations in the hepatitis B surface antigen (HBsAg) have been reported in many parts of the world but are most common in Asian infants; such mutants have several clinical effects, such as the development of hepatocellular carcinoma. Diagnostic failures by commercial assays have reduced the diagnostic effectiveness of HBsAg detection. For example the substitution of an amino acid in the major hydrophilic region of the S gene reduces the binding of hepatitis B surface antibodies leading to immune escape. The safety of blood transfusion may be compromised by current screening tests due to escape from being neutralised by antibodies induced by HBsAg mutants, and undetectable levels...
Expression analysis of SIR2 and SAPs1-4 gene expression in Candida albicans treated with allicin ... more Expression analysis of SIR2 and SAPs1-4 gene expression in Candida albicans treated with allicin compared to fluconazole
Hand, foot and mouth disease (HFMD) is a common viral infection among infants and children. The m... more Hand, foot and mouth disease (HFMD) is a common viral infection among infants and children. The major causative agents of HFMD are enterovirus 71 (EV71) and coxsackievirus A16 (CVA16). Recently, coxsackievirus A6 (CVA6) infections were reported in neighboring countries. Infected infants and children may present with fever, mouth/throat ulcers, rashes and vesicles on hands and feet. Moreover, EV71 infections might cause fatal neurological complications. Since 1997, EV71 caused fatalities in Sarawak and Peninsula Malaysia. The purpose of this study was to identify and classify the viruses which detected from the patients who presenting clinical signs and symptoms of HFMD in Seri Kembangan, Malaysia. From December 2012 until July 2013, a total of 28 specimens were collected from patients with clinical case definitions of HFMD. The HFMD viruses were detected by using semi-nested reverse transcription polymerase chain reaction (snRT-PCR). The positive snRT-PCR products were sequenced and...
One of the main factors for virulence of fungus such as Candida albicans is the ability to change... more One of the main factors for virulence of fungus such as Candida albicans is the ability to change its morphology from yeast to hyphae. Allicin, one of the volatile sulfur-oil compounds from freshly crushed garlic, has a variety of antifungal activities. In this study, the effect of allicin on growth and hyphae production in C. albicans as compared to fluconazole, an antifungal drug was investigated using survival time in vitro and microscopic image at different time intervals. Additionally, the expression of selected genes involved in hyphae formation and development such as SIR2 and SAP1-4 was evaluated by semi-quantitative RT-PCR and relative real time RT-PCR. Allicin was shown to down-regulate the expression of SIR2 (5.54 fold), similar to fluconazole (3.48 fold) at 2x MIC concentrations. Interestingly, allicin had no effect on SAPs1-4 expression, whereas fluconazole was able to suppress SAP4 expression. Our findings showed that allicin was effective in suppressing hyphae develop...
IntroductionIn Yemen, devastated by war, it has been reported that the cholera epidemic disease a... more IntroductionIn Yemen, devastated by war, it has been reported that the cholera epidemic disease among the larg-est of cutting-edge times. The aim of this study is to describe the epidemiological features including the people at risk, drivers of cholera transmission and the drug resistance pattern of the aetiological agent in Sana’a- Yemen.MethodsAll the suspected cholera cases presenting at the medical health laboratory centre in Sana’a during the period from January to May 2019 were considered in this study. Epidemiological variables included in ad-dition to the results of the rapid diagnostic methods and antimicrobial susceptibility. Bacterial cultures were carried out to confirm the diagnosis.Results The cumulative total number of suspected cholera cases from 1st January 2019 to 18th May 2019 is 49096, with 969 have been confirmed as cholera-pos-itive for Vibrio cholerae O1 Ogawa strain by culture at the central public health laboratory in Sana’a and 49 associated deaths (CFR 0.1...
BACKGROUND: Occult hepatitis B is characterized by undetectable levels of surface antigen, but de... more BACKGROUND: Occult hepatitis B is characterized by undetectable levels of surface antigen, but detectable levels of viral DNA and is becoming a major global threat due to: (i) the effect on the health of children born to carrier mothers despite the presence of passive immunoglobulin at birth (ii) immune escape of current vaccines; and (iii) spread through blood and blood products in post transfusion infection, organ donation, and sexual transmission. The aim of this study is to investigate occult hepatitis B virus among vaccines. METHOD: Four hundred and eight, vaccinee were recruited for this study. All samples were tested for hepatitis B surface antigen, hepatitis B surface and core antibodies using enzyme-linked immunosorbent assay kit (DRG International Inc., USA). Positive samples were re-tested to exclude false positive results. Molecular technique using a nested polymerase chain reaction was done using primers specific to the surface gene. RESULTS: Persistence of hepatitis B surface antibodies (≥10 IU/L) was found in 62.5% (255/408) with 37.5% (153/408) having anti-HBs<10 IU/L in circulation. Hepatitis B core antibodies among vaccinated cohort were found to be 5.0% (20/408). Of which 80% (16/20) of the hepatitis B core antibodies positive, have positive hepatitis B surface antibodies (≥10 IU/L) while 20% (4/20) are negative (<10 IU/L). The former is indicating immunity as a result of previous infection and the latter group are referred to as isolated anti-core, as described in previous studies (1). However none of the samples is hepatitis B surface antigen positive. Hepatitis B viral DNA was detected in all the core antigen positive individuals, contrary to studies in Turkey and Taiwan and in line with other similar studies(2). Occult hepatitis B infections have significant clinical importance since they can become reactivated when the immune system is suppressed and can be transmitted through blood or blood product transfusion, organs transplant, and sexual intercourse. CONCLUSION: The result of this study shows occult chronic HBV infection among adults who were vaccinated against hepatitis B vaccine at infant. The anti-HBs produced were induced by the vaccine they received but do not provide protection against the mutant’s variant suggesting primary infection with mutant’s hepatitis B virus.
Background: Zoonotically acquired HEV has been described as one of the most successful zoonotic v... more Background: Zoonotically acquired HEV has been described as one of the most successful zoonotic viral infections in human history. Aim: In this study we characterized HEV comparative genomic analysis as it relates to swine HEV. Materials and methods: A total of 82 chronic hepatitis B patients were recruited from May 2015 to May 2016 for this study. We conducted a serological and molecular investigation of HEV among these patients. The detected HEV were sequenced and the genomes and deduced amino acids were characterized using molecular evolutionary genetic analysis software version 7. Results: Of the 82 chronic hepatitis B patients that were tested, 9.8% (8/82) were found to be HEV positive. Phylogenetic analysis of the HEV RNA sequences showed they are of genotype 4 and demonstrated high sequence identity with a swine isolate from China, with variation in amino acids at position 22, where leucine was present in the Malaysian human isolate while phenylalanine was present in the China swine isolate. Conclusion: Comparative analysis of the human HEV ORF-2 nucleotide sequence suggest zoonotic origin.
The already available expensive conventional therapies for cancer like chemotherapy and radiother... more The already available expensive conventional therapies for cancer like chemotherapy and radiotherapy have a number of side effects such as myelosuppression and neurological, cardiac, pulmonary, and renal toxicity, which pose serious harm to the quality of there is a need to develop treatment options that include more potent and less toxic anticancer drugs as compared to existing drugs. and vegetables because of phytochemical compounds ex activity of antioxidant and free radicals which in turn showing anti semi agents are primarily used in com treatment of a variety of cancers. VLB is used for the treatment of leukaemia, lymphomas, advanced testicular cancer, breast and lung cancers, and Kaposi's sarcoma, and VCR, in addition to the treat acute lymphocytic leukaemia in childhood. VRLB has shown activity against non lung cancer and advanced breast cancer. based, natural process in order to stop the growth of cancer cells. This approach can limit the damage to normal cells and the accompanying side effects caused by conventional chemot agents. drug development. The current findings and known anticancer agents from natural sources are discussed, and recent therapeutic advances in this field Keywords:
Background: Occult hepatitis B infections are becoming a major global threat, but the available d... more Background: Occult hepatitis B infections are becoming a major global threat, but the available data on its prevalence in various parts of the world are often divergent. Objective: This study aimed to detect occult hepatitis B virus in hepatitis B surface antigen-negative serum using anti-HBc as a marker of previous infection. Patient and methods: A total of 1000 randomly selected hepatitis B surface antigen-negative sera from blood donors were tested for hepatitis B core antibody and hepatitis B surface antibody using an ELISA and nested polymerase chain reaction was done using primers specific to the surface gene (S-gene). Results: Of the 1000 samples 55 (5.5%) were found to be reactive, of which 87.3% (48/55) were positive for hepatitis B surface antibody, indicating immunity as a result of previous infection however, that does not exclude active infection with escaped mutant HBV. Nested PCR results showed the presence of hepatitis B viral DNA in all the 55 samples that were positive for core protein, which is in agreement with the hepatitis B surface antibody result. Conclusion: This study reveals the 5.5% prevalence of occult hepatitis B among Malaysian blood donors as well as the reliability of using hepatitis B core antibody in screening for occult hepatitis B infection in low endemic, low socioeconomic settings.
Human respiratory syncytial virus (RSV) is the leading cause of severe lower respiratory tract in... more Human respiratory syncytial virus (RSV) is the leading cause of severe lower respiratory tract infection in infants and young children globally and is a significant pathogen of the elderly and immunocompromised. The M2-2 protein of respiratory syncytial virus (RSV) is particularly important in regulation of viral RNA transcription and replication that could be a potential anti-viral candidate against RSV infection. In this study, we designed and validated siRNAs that specifically target the RSV M2-2 gene. Four siRNAs targeting different regions of the M2-2 gene were designed using web tool. In-vitro evaluation of silencing effect was performed by using RSV infected Vero cell line. Viral M2-2 linked GFP recombinant plasmid was co-transfected with non-targeted siRNA, Pooled siRNA, siRNA 1, siRNA 2, siRNA 3 and siRNA 4 using synthetic cationic polymer. The silencing effect of M2-2 gene at the protein level was measured both qualitatively and quantitatively by using fluorescence microscopy and flow cytometry. Meanwhile, the silencing effect at the mRNA level was assessed by using RT-qPCR. This study showed that all four designed siRNAs can effectively and efficiently silence M2-2 gene. siRNA 2 showed the highest (98%) silencing effect on protein level and siRNA 4 with 83.1% at the mRNA level. The viral assay showed no significant cytopathic effects observed after 6 days post-infection with siRNAs. In conclusion, this study showed the effectiveness of siRNA in silencing M2-2 gene both at the protein and mRNA level which could potentially be used as a novel therapeutic agent in the treatment of RSV infection. However, further study is warranted to investigate the silencing effect of M2-2 protein and inhibition of RSV infection.
The efficacy of allicin compared with fluconazole in alleviating systemic Candida albicans infect... more The efficacy of allicin compared with fluconazole in alleviating systemic Candida albicans infections was evaluated both in vitro and in vivo through a systemic candidiasis mouse model. Determination of in vitro minimum inhibitory concentrations (MICs) for different C. albicans isolates revealed that both allicin and fluconazole showed different MICs that ranged from 0.05 to 12.5 mg mL À1 and 0.25 to 16 mg mL À1 , respectively. A time-kill study showed a significant effect of allicin (P o 0.01) against C. albicans, comparable to that of fluconazole. Scanning electron microscopy observation revealed that, similar to fluconazole, allicin produced structural destruction of C. albicans cell surface at low MIC and lysis or puncture at high MIC concentrations. Treatment of BALB/c mice systemically infected with C. albicans showed that although the allicin treatment (at 5 mg kg À1 day À1) was slightly less efficacious than fluconazole treatment in terms of the fungal load reduction and host survival time, it was still effective against C. albicans in terms of mean survival time, which increased from 8.4 to 15.8 days. These results demonstrate the efficacy of anticandidal effects of allicin both in vitro and in an animal model of candidiasis and affirm the potential of allicin as an adjuvant therapy to fluconazole.
Hand, foot and mouth disease (HFMD) is a common viral infection among infants and children. The m... more Hand, foot and mouth disease (HFMD) is a common viral infection among infants and children. The major causative agents of HFMD are enterovirus 71 (EV71) and coxsackievirus A16 (CVA16). Recently, coxsackievirus A6 (CVA6) infections were reported in neighboring countries. Infected infants and children may present with fever, mouth/throat ulcers, rashes and vesicles on hands and feet. Moreover, EV71 infections might cause fatal neurological complications. Since 1997, EV71 caused fatalities in Sarawak and Peninsula Malaysia. The purpose of this study was to identify and classify the viruses which detected from the patients who presenting clinical signs and symptoms of HFMD in Seri Kembangan, Malaysia. From December 2012 until July 2013, a total of 28 specimens were collected from patients with clinical case definitions of HFMD. The HFMD viruses were detected by using semi-nested reverse transcription polymerase chain reaction (snRT-PCR). The positive snRT-PCR products were sequenced and...
The epidemiology and antibiotic susceptibility of Shigella species changes over time. Updated sus... more The epidemiology and antibiotic susceptibility of Shigella species changes over time. Updated susceptibility knowledge is necessary for appropriate empirical antibiotic treatment. Thus, this research aimed to study these changes in 2 time periods with an interval of 10 years. Two hundreds and three Shigella strains, isolated from stool samples of diarrheic patients at the Central Health Laboratory in Sana'a, Yemen in 2 time periods (1993 and 2003) with a 10-year interval, were examined for serotyping and drug resistance pattern. Resistance patterns of the strains to 12 commonly used antimicrobial agents and minimum inhibitory concentrations of the antibiotics were tested. Shigella flexneri (60%) was found to be the most common isolate of the total Shigella species, followed by Shigella dysenteriae (28.6%) and Shigella boydii (11.3%). In Shigella flexneri strains, Shigella flexneri 3 (30.5%) was the most prevalent serotype, followed by Shigella flexneri 6 (17.2%), and Shigella fl...
BACKGROUND Healthcare workers (HCWs) are at increased risk of getting influenza than the general ... more BACKGROUND Healthcare workers (HCWs) are at increased risk of getting influenza than the general population, therefore putting patients at risk of nosocomial infection. Influenza vaccination coverage among HCWs is low despite the availability of a safe and effective vaccine. However, the reasons for such a poor uptake are not well reported in Malaysia. This study aimed at assessing the rate of influenza vaccination uptake, knowledge and attitude of healthcare workers regarding influenza, and employers' policy on influenza vaccination. METHODS A cross-sectional questionnaire survey was conducted in three hospitals in the Klang Valley. Mann-Whitney test was used to assess possible differences in knowledge and attitude towards flu vaccination and the χ2 was used for categorical variables. Analyses were performed with SPSS 22.0. RESULTS A total of 690 questionnaires were distributed; 527 were returned (giving a response rate of 76.4%. The vaccine uptake was 51.4% with the majority (...
Hepatitis B virus infection is a serious health problem worldwide, and more than 350 million peop... more Hepatitis B virus infection is a serious health problem worldwide, and more than 350 million people are chronic carriers, constituting a major global threat. Southeast Asia and the Western Pacific have the highest levels of endemicity in the world, with an estimated seroprevalence ranging between 2% and 31%. Mutations in the hepatitis B surface antigen (HBsAg) have been reported in many parts of the world but are most common in Asian infants; such mutants have several clinical effects, such as the development of hepatocellular carcinoma. Diagnostic failures by commercial assays have reduced the diagnostic effectiveness of HBsAg detection. For example the substitution of an amino acid in the major hydrophilic region of the S gene reduces the binding of hepatitis B surface antibodies leading to immune escape. The safety of blood transfusion may be compromised by current screening tests due to escape from being neutralised by antibodies induced by HBsAg mutants, and undetectable levels...
Expression analysis of SIR2 and SAPs1-4 gene expression in Candida albicans treated with allicin ... more Expression analysis of SIR2 and SAPs1-4 gene expression in Candida albicans treated with allicin compared to fluconazole
Hand, foot and mouth disease (HFMD) is a common viral infection among infants and children. The m... more Hand, foot and mouth disease (HFMD) is a common viral infection among infants and children. The major causative agents of HFMD are enterovirus 71 (EV71) and coxsackievirus A16 (CVA16). Recently, coxsackievirus A6 (CVA6) infections were reported in neighboring countries. Infected infants and children may present with fever, mouth/throat ulcers, rashes and vesicles on hands and feet. Moreover, EV71 infections might cause fatal neurological complications. Since 1997, EV71 caused fatalities in Sarawak and Peninsula Malaysia. The purpose of this study was to identify and classify the viruses which detected from the patients who presenting clinical signs and symptoms of HFMD in Seri Kembangan, Malaysia. From December 2012 until July 2013, a total of 28 specimens were collected from patients with clinical case definitions of HFMD. The HFMD viruses were detected by using semi-nested reverse transcription polymerase chain reaction (snRT-PCR). The positive snRT-PCR products were sequenced and...
One of the main factors for virulence of fungus such as Candida albicans is the ability to change... more One of the main factors for virulence of fungus such as Candida albicans is the ability to change its morphology from yeast to hyphae. Allicin, one of the volatile sulfur-oil compounds from freshly crushed garlic, has a variety of antifungal activities. In this study, the effect of allicin on growth and hyphae production in C. albicans as compared to fluconazole, an antifungal drug was investigated using survival time in vitro and microscopic image at different time intervals. Additionally, the expression of selected genes involved in hyphae formation and development such as SIR2 and SAP1-4 was evaluated by semi-quantitative RT-PCR and relative real time RT-PCR. Allicin was shown to down-regulate the expression of SIR2 (5.54 fold), similar to fluconazole (3.48 fold) at 2x MIC concentrations. Interestingly, allicin had no effect on SAPs1-4 expression, whereas fluconazole was able to suppress SAP4 expression. Our findings showed that allicin was effective in suppressing hyphae develop...
IntroductionIn Yemen, devastated by war, it has been reported that the cholera epidemic disease a... more IntroductionIn Yemen, devastated by war, it has been reported that the cholera epidemic disease among the larg-est of cutting-edge times. The aim of this study is to describe the epidemiological features including the people at risk, drivers of cholera transmission and the drug resistance pattern of the aetiological agent in Sana’a- Yemen.MethodsAll the suspected cholera cases presenting at the medical health laboratory centre in Sana’a during the period from January to May 2019 were considered in this study. Epidemiological variables included in ad-dition to the results of the rapid diagnostic methods and antimicrobial susceptibility. Bacterial cultures were carried out to confirm the diagnosis.Results The cumulative total number of suspected cholera cases from 1st January 2019 to 18th May 2019 is 49096, with 969 have been confirmed as cholera-pos-itive for Vibrio cholerae O1 Ogawa strain by culture at the central public health laboratory in Sana’a and 49 associated deaths (CFR 0.1...
BACKGROUND: Occult hepatitis B is characterized by undetectable levels of surface antigen, but de... more BACKGROUND: Occult hepatitis B is characterized by undetectable levels of surface antigen, but detectable levels of viral DNA and is becoming a major global threat due to: (i) the effect on the health of children born to carrier mothers despite the presence of passive immunoglobulin at birth (ii) immune escape of current vaccines; and (iii) spread through blood and blood products in post transfusion infection, organ donation, and sexual transmission. The aim of this study is to investigate occult hepatitis B virus among vaccines. METHOD: Four hundred and eight, vaccinee were recruited for this study. All samples were tested for hepatitis B surface antigen, hepatitis B surface and core antibodies using enzyme-linked immunosorbent assay kit (DRG International Inc., USA). Positive samples were re-tested to exclude false positive results. Molecular technique using a nested polymerase chain reaction was done using primers specific to the surface gene. RESULTS: Persistence of hepatitis B surface antibodies (≥10 IU/L) was found in 62.5% (255/408) with 37.5% (153/408) having anti-HBs<10 IU/L in circulation. Hepatitis B core antibodies among vaccinated cohort were found to be 5.0% (20/408). Of which 80% (16/20) of the hepatitis B core antibodies positive, have positive hepatitis B surface antibodies (≥10 IU/L) while 20% (4/20) are negative (<10 IU/L). The former is indicating immunity as a result of previous infection and the latter group are referred to as isolated anti-core, as described in previous studies (1). However none of the samples is hepatitis B surface antigen positive. Hepatitis B viral DNA was detected in all the core antigen positive individuals, contrary to studies in Turkey and Taiwan and in line with other similar studies(2). Occult hepatitis B infections have significant clinical importance since they can become reactivated when the immune system is suppressed and can be transmitted through blood or blood product transfusion, organs transplant, and sexual intercourse. CONCLUSION: The result of this study shows occult chronic HBV infection among adults who were vaccinated against hepatitis B vaccine at infant. The anti-HBs produced were induced by the vaccine they received but do not provide protection against the mutant’s variant suggesting primary infection with mutant’s hepatitis B virus.
Background: Zoonotically acquired HEV has been described as one of the most successful zoonotic v... more Background: Zoonotically acquired HEV has been described as one of the most successful zoonotic viral infections in human history. Aim: In this study we characterized HEV comparative genomic analysis as it relates to swine HEV. Materials and methods: A total of 82 chronic hepatitis B patients were recruited from May 2015 to May 2016 for this study. We conducted a serological and molecular investigation of HEV among these patients. The detected HEV were sequenced and the genomes and deduced amino acids were characterized using molecular evolutionary genetic analysis software version 7. Results: Of the 82 chronic hepatitis B patients that were tested, 9.8% (8/82) were found to be HEV positive. Phylogenetic analysis of the HEV RNA sequences showed they are of genotype 4 and demonstrated high sequence identity with a swine isolate from China, with variation in amino acids at position 22, where leucine was present in the Malaysian human isolate while phenylalanine was present in the China swine isolate. Conclusion: Comparative analysis of the human HEV ORF-2 nucleotide sequence suggest zoonotic origin.
The already available expensive conventional therapies for cancer like chemotherapy and radiother... more The already available expensive conventional therapies for cancer like chemotherapy and radiotherapy have a number of side effects such as myelosuppression and neurological, cardiac, pulmonary, and renal toxicity, which pose serious harm to the quality of there is a need to develop treatment options that include more potent and less toxic anticancer drugs as compared to existing drugs. and vegetables because of phytochemical compounds ex activity of antioxidant and free radicals which in turn showing anti semi agents are primarily used in com treatment of a variety of cancers. VLB is used for the treatment of leukaemia, lymphomas, advanced testicular cancer, breast and lung cancers, and Kaposi's sarcoma, and VCR, in addition to the treat acute lymphocytic leukaemia in childhood. VRLB has shown activity against non lung cancer and advanced breast cancer. based, natural process in order to stop the growth of cancer cells. This approach can limit the damage to normal cells and the accompanying side effects caused by conventional chemot agents. drug development. The current findings and known anticancer agents from natural sources are discussed, and recent therapeutic advances in this field Keywords:
Background: Occult hepatitis B infections are becoming a major global threat, but the available d... more Background: Occult hepatitis B infections are becoming a major global threat, but the available data on its prevalence in various parts of the world are often divergent. Objective: This study aimed to detect occult hepatitis B virus in hepatitis B surface antigen-negative serum using anti-HBc as a marker of previous infection. Patient and methods: A total of 1000 randomly selected hepatitis B surface antigen-negative sera from blood donors were tested for hepatitis B core antibody and hepatitis B surface antibody using an ELISA and nested polymerase chain reaction was done using primers specific to the surface gene (S-gene). Results: Of the 1000 samples 55 (5.5%) were found to be reactive, of which 87.3% (48/55) were positive for hepatitis B surface antibody, indicating immunity as a result of previous infection however, that does not exclude active infection with escaped mutant HBV. Nested PCR results showed the presence of hepatitis B viral DNA in all the 55 samples that were positive for core protein, which is in agreement with the hepatitis B surface antibody result. Conclusion: This study reveals the 5.5% prevalence of occult hepatitis B among Malaysian blood donors as well as the reliability of using hepatitis B core antibody in screening for occult hepatitis B infection in low endemic, low socioeconomic settings.
Human respiratory syncytial virus (RSV) is the leading cause of severe lower respiratory tract in... more Human respiratory syncytial virus (RSV) is the leading cause of severe lower respiratory tract infection in infants and young children globally and is a significant pathogen of the elderly and immunocompromised. The M2-2 protein of respiratory syncytial virus (RSV) is particularly important in regulation of viral RNA transcription and replication that could be a potential anti-viral candidate against RSV infection. In this study, we designed and validated siRNAs that specifically target the RSV M2-2 gene. Four siRNAs targeting different regions of the M2-2 gene were designed using web tool. In-vitro evaluation of silencing effect was performed by using RSV infected Vero cell line. Viral M2-2 linked GFP recombinant plasmid was co-transfected with non-targeted siRNA, Pooled siRNA, siRNA 1, siRNA 2, siRNA 3 and siRNA 4 using synthetic cationic polymer. The silencing effect of M2-2 gene at the protein level was measured both qualitatively and quantitatively by using fluorescence microscopy and flow cytometry. Meanwhile, the silencing effect at the mRNA level was assessed by using RT-qPCR. This study showed that all four designed siRNAs can effectively and efficiently silence M2-2 gene. siRNA 2 showed the highest (98%) silencing effect on protein level and siRNA 4 with 83.1% at the mRNA level. The viral assay showed no significant cytopathic effects observed after 6 days post-infection with siRNAs. In conclusion, this study showed the effectiveness of siRNA in silencing M2-2 gene both at the protein and mRNA level which could potentially be used as a novel therapeutic agent in the treatment of RSV infection. However, further study is warranted to investigate the silencing effect of M2-2 protein and inhibition of RSV infection.
The efficacy of allicin compared with fluconazole in alleviating systemic Candida albicans infect... more The efficacy of allicin compared with fluconazole in alleviating systemic Candida albicans infections was evaluated both in vitro and in vivo through a systemic candidiasis mouse model. Determination of in vitro minimum inhibitory concentrations (MICs) for different C. albicans isolates revealed that both allicin and fluconazole showed different MICs that ranged from 0.05 to 12.5 mg mL À1 and 0.25 to 16 mg mL À1 , respectively. A time-kill study showed a significant effect of allicin (P o 0.01) against C. albicans, comparable to that of fluconazole. Scanning electron microscopy observation revealed that, similar to fluconazole, allicin produced structural destruction of C. albicans cell surface at low MIC and lysis or puncture at high MIC concentrations. Treatment of BALB/c mice systemically infected with C. albicans showed that although the allicin treatment (at 5 mg kg À1 day À1) was slightly less efficacious than fluconazole treatment in terms of the fungal load reduction and host survival time, it was still effective against C. albicans in terms of mean survival time, which increased from 8.4 to 15.8 days. These results demonstrate the efficacy of anticandidal effects of allicin both in vitro and in an animal model of candidiasis and affirm the potential of allicin as an adjuvant therapy to fluconazole.
Hand, foot and mouth disease (HFMD) is a common viral infection among infants and children. The m... more Hand, foot and mouth disease (HFMD) is a common viral infection among infants and children. The major causative agents of HFMD are enterovirus 71 (EV71) and coxsackievirus A16 (CVA16). Recently, coxsackievirus A6 (CVA6) infections were reported in neighboring countries. Infected infants and children may present with fever, mouth/throat ulcers, rashes and vesicles on hands and feet. Moreover, EV71 infections might cause fatal neurological complications. Since 1997, EV71 caused fatalities in Sarawak and Peninsula Malaysia. The purpose of this study was to identify and classify the viruses which detected from the patients who presenting clinical signs and symptoms of HFMD in Seri Kembangan, Malaysia. From December 2012 until July 2013, a total of 28 specimens were collected from patients with clinical case definitions of HFMD. The HFMD viruses were detected by using semi-nested reverse transcription polymerase chain reaction (snRT-PCR). The positive snRT-PCR products were sequenced and...
The epidemiology and antibiotic susceptibility of Shigella species changes over time. Updated sus... more The epidemiology and antibiotic susceptibility of Shigella species changes over time. Updated susceptibility knowledge is necessary for appropriate empirical antibiotic treatment. Thus, this research aimed to study these changes in 2 time periods with an interval of 10 years. Two hundreds and three Shigella strains, isolated from stool samples of diarrheic patients at the Central Health Laboratory in Sana'a, Yemen in 2 time periods (1993 and 2003) with a 10-year interval, were examined for serotyping and drug resistance pattern. Resistance patterns of the strains to 12 commonly used antimicrobial agents and minimum inhibitory concentrations of the antibiotics were tested. Shigella flexneri (60%) was found to be the most common isolate of the total Shigella species, followed by Shigella dysenteriae (28.6%) and Shigella boydii (11.3%). In Shigella flexneri strains, Shigella flexneri 3 (30.5%) was the most prevalent serotype, followed by Shigella flexneri 6 (17.2%), and Shigella fl...
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