Downregulation of LAMB3 Altered the Carcinogenic Properties of Human Papillomavirus 16-Positive Cervical Cancer Cells

Nearly all cervical cancer cases are caused by infection with high-risk human papillomavirus (HR-HPV) types. The mechanism of cervical cell transformation is related to the powerful action of viral oncoproteins and cellular gene alterations. Transcriptomic data from cervical cancer and normal cervical cells were utilized to identify upregulated genes and their associated pathways. The laminin subunit beta-3 (LAMB3) mRNAwas overexpressed in cervical cancer and was chosen for functional analysis. The LAMB3 was predominantly expressed in the extracellular region and the plasma membrane, which play a role in protein binding and cell adhesion molecule binding, leading to cell migration and tissue development. LAMB3 was found to be implicated in the pathway in cancer and the PI3K-AKT signaling pathway. LAMB3 knockdown decreased cell migration, invasion, anchorage-dependent and anchorage-independent cell growth and increased the number of apoptotic cells. These effects were linked to a decrease in protein levels involved in the PI3K-AKT signaling pathway and an increase in p53 protein. This study demonstrated that LAMB3 could promote cervical cancer cell migration, invasion and survival.

Impact of actin polymerization and filopodia formation on herpes simplex virus entry in epithelial, neuronal, and T lymphocyte cells

Herpes simplex virus type 1 (HSV-1) has been known as a common viral pathogen that can infect several parts of the body, leading to various clinical manifestations. According to this diverse manifestation, HSV-1 infection in many cell types was demonstrated. Besides the HSV-1 cell tropism, e.g., fibroblast, epithelial, mucosal cells, and neurons, HSV-1 infections can occur in human T lymphocyte cells, especially in activated T cells. In addition, several studies found that actin polymerization and filopodia formation support HSV-1 infection in diverse cell types. Hence, the goal of this review is to explore the mechanism of HSV-1 infection in various types of cells involving filopodia formation and highlight potential future directions for HSV-1 entry-related research. Moreover, this review covers several strategies for possible anti-HSV drugs focused on the entry step, offering insights into potential therapeutic interventions.

Inhibitory efficiency of Andrographis paniculata extract on viral multiplication and nitric oxide production

Andrographis paniculata (Burm. F.) Nees is a medicinal plant previously reported with broad-spectrum antivirals but the mode of inhibition remains elusive. The objective of this study was to identify the most active fraction from A. paniculata ethanol extract (APE, APE-2A, APE-2B and APE-2C) and dry powder extract (APSP) against influenza A (H3N2), representing RNA viruses, and herpes simplex virus-1 (HSV-1), representing DNA viruses. The results showed that the fractions APSP, APE, APE-2B, and APE-2C directly neutralized the HSV-1 and influenza A (H3N2) when incubated at room temperature for 60 min before infecting the cells. The results also showed that the additional APE-2A fraction also directly neutralized the influenza A (H3N2), but not the HSV-1. The APE, APE-2B and APE-2C inhibited the HSV-1 by more than 0.5 log when the fractions were introduced after infection. Similarly, the APSP and APE inhibited the influenza A (H3N2) more than 0.5 log after infection. Only 50 μg/mL APE-2C inhibited the viruses greater than 0.5 log. In addition, A. paniculata extracts were also evaluated for their interfering capacities against nitric oxide (NO) production in LPS-activated RAW 264.7 macrophages. As well, APE-2C potently inhibited NO production at the IC50 of 6.08 μg/mL. HPLC and LC-MS analysis indicated that the most actively antiviral fractions did not contain any andrographolide derivatives, whereas the andrographolide-rich fractions showed moderate activity.

HPV16E1 downregulation altered the cell characteristics involved in cervical cancer development

The primary causes of cervical cancer are human papillomavirus type 16 (HPV16) and/or other high-risk (Hr -) HPV infections. Hr-HPVE5, E6, and E7 have been identified as oncoproteins that play roles in the development of cancer. However, other HPV proteins, especially E1, may also be involved in cancer development. In this study, the role of HPV16E1 in cervical carcinogenesis was examined by siRNA knockdown experiments using SiHa cells as a model. The results showed that HPV16E1 regulated P-FOXO3a and HPV16E7 expression. Various cell functions associated with the hallmarks of cancer, including cell viability, colony formation, invasion, and anchorage-independent cell growth, were altered when HPV16E1 was downregulated. However, no effect on cell migration and apoptosis properties was found. Moreover, HPV16E1 downregulation resulted in an increase in cisplatin susceptibility. In conclusion, this is the first demonstration that HPV16E1 might be regarded as a possible novel oncoprotein involved in several processes related to oncogenesis.

Cervical Microbiome in Women Infected with HPV16 and High-Risk HPVs

Human papillomavirus type 16 (HPV16) and/or high-risk (Hr-) HPV are the main causes of cervical cancer. Another element that may contribute to the development of cervical cancer is the microbiota. To date, no study has investigated the entire cervical microbiome, which consists of bacteria, fungi, and viruses. In this study, cervical samples with different histopathology (CIN1, CIN2, and CIN3), with or without HPV16 and Hr-HPVs infection, were enrolled. From bacterial community analysis, 115 bacterial species were found and separated into 2 distinct categories based on Lactobacillus abundance: Lactobacilli-dominated (LD) and non-Lactobacilli-dominated (NLD) groups. The LD group had significantly less bacterial diversity than the NLD group. In addition, the variety of bacteria was contingent on the prevalence of HPV infection. Among distinct histological groups, an abundance of L. iners (>60% of total Lactobacillus spp.) was discovered in both groups. A few fungi, e.g., C. albicans, were identified in the fungal community. The viral community analysis revealed that the presence of HPV considerably reduced the diversity of human viruses. Taken together, when we analyzed all our results collectively, we discovered that HPV infection was a significant determinant in the diversity of bacteria and human viruses in the cervix.

Role of HPV16 E1 in cervical carcinogenesis

Cervical cancer is the fourth most common cancer in women worldwide. More than 90% of cases are caused by the human papillomavirus (HPV). Vaccines developed only guard against a few HPV types and do not protect people who have already been infected. HPV is a small DNA virus that infects the basal layer of the stratified epithelium of the skin and mucosa through small breaks and replicates as the cells differentiate. The mucosal types of HPV can be classified into low-risk and high-risk groups, based on their association with cancer. Among HPV types in high-risk group, HPV type 16 (HPV-16) is the most common, causing 50% of all cancer cases. HPV infection can occur as transient or persistent infections, based on the ability of immune system to clear the virus. Persistent infection is characterized by the integration of HPV genome. HPV-16 exhibits a different integration pattern, with only 50% reported to be integrated at the carcinoma stage. Replication of the HPV genome depends on protein E1, an ATP-dependent helicase. E1 is essential for the amplification of the viral episome in infected cells. Previous studies have shown that E1 does not only act as a helicase protein but is also involved in recruiting and interacting with other host proteins. E1 has also been deemed to drive host cell proliferation. Recent studies have emphasized the emerging role of HPV E1 in cervical carcinogenesis. In this review, a possible mechanism by which E1 drives cell proliferation and oncogenesis will be discussed.

Detection of Global DNA Methylation in Cervical Intraepithelial Neoplasia and Cancerous Lesions by Pyrosequencing and Enzyme-Linked Immunosorbent Assays

Background:

Cervical cancer is one of the most significant cancer found in women worldwide especially in developing countries. Previous reports showed that global DNA hypomethylation was correlated with various types of cancer including cervical cancer.

Methods:

Long interspersed nuclear element-1 (LINE1) pyrosequencing and Enzyme linked-immunosorbent assay (ELISA) assays were used for detection of global DNA methylation. The ELISA results were compared to bisulfite LINE1 pyrosequencing assay.

Results:

Different cervical cancer cell lines (CaSki, SiHa, HeLa, ME180, MS751, C33A) showed low global methylation percentage when compared to normal white blood cells by ELISA assay (1.47%-5.09% vs 8.20%, respectively) and by LINE1 pyrosequencing (20%-45% vs 62%, respectively). Global DNA methylation levels in cervical cancer samples were lower than precancerous lesions (Normal-CIN3) by LINE1 pyrosequencing (mean, 48.8% vs 56.9%, respectively, p<0.05) and ELISA assay (mean, 3.03% vs 3.85%, respectively, p<0.05).

Conclusion:

Global DNA hypomethylation was predominantly found in cervical cancer samples detected by ELISA and LINE1 pyrosequencing assays and could be used as triage tests in cervical cancer screening. ELISA assay is a suitable method for detection of global DNA methylation in large population; however, it should be further evaluated in a large clinical samples in order to be used as screening method.

HPV16 E1 dysregulated cellular genes involved in cell proliferation and host DNA damage: A possible role in cervical carcinogenesis

HPV16 is the most prominent cause of cervical cancer. HPV16 E1, a helicase required for HPV replication exhibits increased expression in association with cervical cancer progression, suggesting that E1 has a similar effect on the host as the HPV16 E6 and E7 oncoproteins. This study aimed to determine whether expression of HPV16 E1 correlated with carcinogenesis by modulating cellular pathways involved in cervical cancer. HEK293T cells were transfected with pEGFP, pEGFPE1 or truncated forms of HPV16 E1. Cell proliferation, cell death, and the impact of HPV16 E1 on host gene expression was then evaluated. HPV16 E1 overexpression resulted in a significant reduction of cell viability and cellular proliferation (p-value<0.0001). Moreover, prolonged expression of HPV16 E1 significantly induced both apoptotic and necrotic cell death, which was partially inhibited by QVD-OPH, a broad-spectrum caspase inhibitor. Microarray, real time RT-PCR and kinetic host gene expression analyses revealed that HPV16 E1 overexpression resulted in the downregulation of genes involved in protein synthesis (RPL36A), metabolism (ALDOC), cellular proliferation (CREB5, HIF1A, JMJDIC, FOXO3, NFKB1, PIK3CA, TSC22D3), DNA damage (ATR, BRCA1 and CHEK1) and immune response (ISG20) pathways. How these genetic changes contribute to HPV16 E1-mediated cervical carcinogenesis warrants further studies.

Human papillomavirus 16 L1 gene methylation as a potential biomarker for predicting anal intraepithelial neoplasia in men who have sex with men (MSM)

The human papillomavirus (HPV) 16 early promoter and L1 gene methylation were quantitatively measured using pyrosequencing assay in anal cells collected from men who have sex with men (MSM) to determine potential biomarkers for HPV-related anal cancer. The methylation patterns of HPV16 genes, including the early promoter (CpG 31, 37, 43, 52, and 58) and L1 genes (CpG 5600, 5606, 5609, 5615, 7136, and 7145), were analyzed in 178 anal samples. The samples were diagnosed as normal, anal intraepithelial neoplasia (AIN) 1, AIN2, and AIN3. Low methylation levels of the early promoter (< 10%) and L1 genes (< 20%) were found in all detected normal anal cells. In comparison, medium to high methylation (≥ 20–60%) in the early promoter was found in 1.5% (1/67) and 5% (2/40) of AIN1 and AIN2-3 samples, respectively. Interestingly, slightly increased L1 gene methylation levels (≥ 20–60%), especially at the HPV16 5’L1 regions CpGs 5600 and 5609, were demonstrated in AIN2-3 specimen. Moreover, a negative correlation between high HPV16 L1 gene methylation at CpGs 5600, 5609, 5615, and 7145 and a percentual CD4 count was found in AIN3 HIV positive cases. When comparing the methylation status of AIN2-3 to that of normal/AIN1 lesions, the results indicated the potential of using HPV16 L1 gene methylation as a biomarker for HPV-related cancer screening.

Prevalence of Human Papillomavirus Genotypes in Pterygia from Thai Individuals

Purpose: Pterygium, a common ocular growth, has an unknown pathogenesis and aetiology. Environmental factors such as ultraviolet light, genetic factors and viral infections may be implicated in the development of pterygia. Human papillomavirus (HPV), an oncogenic virus, has previous been detected in individuals with pterygia. The aim of this study was to assess the prevalence of HPV genotypes in pterygia from Thai individuals.Methods: DNA was extracted from 389 pterygia. HPV was detected by nested PCR and HPV genotyping was conducted using reverse hybridization. The DNA sequences of HPV-L1 genes were analyzed.Results: HPV was detected in only 6.8% (25/389) of pterygia from Thai individuals. The majority (16/25, 64%) of strains were genotyped as HPV-16 and the remainder (9/25, 36%) could not be typed. Four pterygia showed evidence of coinfection by HPV-16 and either HPV-18 (2/25, 8%) or HPV-58 (2/25, 8%). Nine of 11 samples showed the same HPV-16 L1 gene sequence that was identical to a HPV-16 reference sequence in GenBank. The remaining two samples each bore silent single nucleotide mutations (T1078G and T1081A) that did not result in amino acid changes.Conclusion: HPV, especially HPV-16, may be one of the pathogens causing pterygia in Thai individuals. Genotyping data suggested that HPV-16 from pterygia may be similar in sequence to HPV-16 causing cervical cancer.

Elevated HPV16 E1 Expression Is Associated with Cervical Cancer Progression

OBJECTIVES

The primary replication protein, HPV E1, has been shown to play a role in mitigating host defence and disrupting normal cell cycle processes, leading to the development of cancer. This study investigated the expression profile of HPV16 E1 in various stages of cervical cancer development and the factors that control E1 expression.

METHODS

One hundred and twenty-four HPV16-positive cervical samples ranging from normal to CIN 1, CIN 2/3, and SCC lesions were studied. E1 mRNA expression was determined by ddPCR. Methylation of promoters p97 and p670 was quantified by pyrosequencing, while PCR, qPCR, and sequencing were used to determine the physical state and variations of the HPV16 E1 genome.

RESULTS

Increased E1 mRNA expression related to disease progression (normal 0.18, CIN 1 0.41, CIN 2/3 0.65, and SCC 0.79) was demonstrated with a significant positive correlation (r = 0.661, p = 0.019). No association between physical state and E1 expression was found. Methylation of p97 and p670 promoters showed significant elevation in SCC compared to normal samples. Only 4.2% showed genomic variations of HPV16 E1 63-bp duplication.

CONCLUSION

E1 may play a role in cancer development. The detection of E1 mRNA and promoter methylation may be useful as cancer prognostic markers.

Immunogold-agglutination assay for direct detection of HPV-16 E6 and L1 proteins from clinical specimens

HPV-16 infection is the most common cause of cervical cancer. As HPV-16 transforms the cell, E6 oncoprotein is over-expressed. Therefore, molecular detection of HPV-16 E6 mRNA is now being used for diagnosis and prediction of cancer development. Besides detecting E6 mRNA, a rapid lateral flow detecting the E6 protein using enzyme immunoassay is also now on market with a sensitivity of 53.5% for cervical intraepithelial neoplasia (CIN)-3 or more severe (CIN-3+). Here, an immunogold-agglutination assay was developed to detect not only HPV-16 E6 protein but also L1, a major capsid protein found in the productive stage of the virus. Evaluation of this test using HPV-16 DNA positive cervical samples showed that the HPV-16 E6 immunogold-agglutination assay results correlated well with the progression of the cervical lesions, i.e., 10.34% of CIN-1, 68.75% of CIN-3 and 80% of cancer (CaCx) and none for healthy normal samples. Interestingly, the HPV-16 L1 protein was found in most of the cases with cancer indicating the possibility of virion production. Immunogold-agglutination assay for E6 protein is simpler, easier to be performed with a sensitivity of 73.1% for CIN-3+ suggesting a good method for laboratory diagnostic use.

Simplified dengue virus microwell plaque assay using an automated quantification program

The plaque assay is essential for virion quantitation but the classic protocol requires considerable efforts. A simplified dengue 96-well plaque assay with automated quantitation program is an alternative to access the level of infectious virus. Dengue plaque assay was simplified using LLC/MK2 cells and virus mixing simultaneously before semisolid addition. Results were obtained using a flatbed scanner and analysis by the self-written program optimized to manual reads. The newly developed microwell system was accurate to the standard assay because 19 independent titrations from all subtypes obtained from both systems differed less than a log10 p.f.u./ml with no significance (p>0.05) with good correlation (R²=0.9058). Coefficient of variations within and between assays, indicating assay reliability and repeatability, were 19.29%, and 12.50%, respectively. This method serves various experimental designs in drug discovery that requires viral titers assessment. Effective concentrations (EC₉₀) results showed no significant difference between 24- and 96-well assays (p>0.05). Compound screening for potential antivirals and clinical isolate titrations were successfully arranged. The method contains distinguished features including protocol simplicity, less reagent consumption in microwell format, convenient and affordable data acquisition and analysis system.

One of the Mechanisms to Increase HSV-1 Uptake in HSV-1-Infected, Activated T Lymphocytes Is the Formation of Filopodia

OBJECTIVES

To explore the host transcription factor E2F-1 and/or any mechanisms that may support viral entry and its effect on the HSV-1 production in anti-CD3-activated Jurkat cells.

METHODS

The expressions of ICP4, HVEM and E2F-1 were studied using reverse transcription-PCR and Western blot. HSV-1 production was determined by plaque titration assay and HSV-1 DNA load was quantified by real-time PCR. The viral uptake was observed by electron microscopy.

RESULTS

In anti-CD3-activated Jurkat cells, there was a significant increase in the HSV-1 production. The expression of ICP4 mRNA after HSV-1 infection occurred 2 h prior to the synthesis of the ICP4 protein, which was significantly higher in activated than nonactivated T cells. There were no significant differences in the expressions of E2F-1 mRNA. The HVEM expression was positively correlated with the HSV-1 DNA in the activated T cells. From the electron micrograph, the formations of filopodia were observed only in HSV-1-infected, activated cells.

CONCLUSIONS

High expressions of viral receptor protein and filopodia formations are the key factors that enhance the HSV-1 entry into activated T lymphocytes, resulting in an increased production of the virus.

Novel p16 binding peptide development for p16-overexpressing cancer cell detection using phage display

Protein p(16INK4a) (p16) is a well-known biomarker for diagnosis of human papillomavirus (HPV) related cancers. In this work, we identify novel p16 binding peptides by using phage display selection method. A random heptamer phage display library was screened on purified recombinant p16 protein-coated plates to elute only the bound phages from p16 surfaces. Binding affinity of the bound phages was compared with each other by enzyme-linked immunosorbent assay (ELISA), fluorescence imaging technique, and bioinformatic computations. Binding specificity and binding selectivity of the best candidate phage-displayed p16 binding peptide were evaluated by peptide blocking experiment in competition with p16 monoclonal antibody and fluorescence imaging technique, respectively. Five candidate phage-displayed peptides were isolated from the phage display selection method. All candidate p16 binding phages show better binding affinity than wild-type phage in ELISA test, but only three of them can discriminate p16-overexpressing cancer cell, CaSki, from normal uterine fibroblast cell, HUF, with relative fluorescence intensities from 2.6 to 4.2-fold greater than those of wild-type phage. Bioinformatic results indicate that peptide 'Ser-His-Ser-Leu-Leu-Ser-Ser' binds to p16 molecule with the best binding score and does not interfere with the common protein functions of p16. Peptide blocking experiment shows that the phage-displayed peptide 'Ser-His-Ser-Leu-Leu-Ser-Ser' can conceal p16 from monoclonal antibody interaction. This phage clone also selectively interacts with the p16 positive cell lines, and thus, it can be applied for p16-overexpressing cell detection.

Cytotoxic function of gamma delta (gamma/delta) T cells against pamidronate-treated cervical cancer cells

The cytotoxic function of polyclonal expanded gamma/delta T cells against pamidronate-treated cervical cancer cells in vitro and in vivo were determined. The gamma/delta T cells were isolated and purified from PBMCs by using miniMACS and were later treated with 10 microM pamidronate. The expansion of gamma/delta T cells was 15 times more than the non-stimulated cells. Among the expanded gamma/delta T cells, 47% were Vgamma9/Vdelta2 T cells with a purity of 87%. Analyzing the cytotoxic function of gamma/delta T cells against 3 cervical cancer cells in vitro by LDH cytotoxicity test revealed that the killing efficacy increased if the cervical cancer cells (HeLa, SiHa and CaSki) were pretreated with pamidronate. The presence of CD107 on gamma/delta T cells indicated the degranulation of perforin and granzyme pathway is one of the mechanisms used by the gamma/delta T cells to kill cancer cells. The killing ability of gamma/delta T cells against cancer cells in vivo was preliminary assessed by using mouse baring HeLa cells. The results demonstrated that gamma/delta T cells induce apoptosis in tumor cells. Our study supports the usefulness of gamma/delta T cells in future development of immunotherapy for cervical cancer.

HIV-1 replication in HIV-infected individuals is significantly reduced when peripheral blood mononuclear cells are superinfected with HSV-1

Herpes simplex virus (HSV) can cause generalized infection in human immunodeficiency virus- (HIV-) infected patients leading to death. This study investigated HSV-1 replication in PBMCs from 25 HIV-infected individuals and 15 healthy donors and the effects of HSV-1 superinfection on HIV-1 production. Herpes viral entry mediator (HVEM) receptor on T lymphocytes was also evaluated. Our results confirmed that the number of activated (CD3+ and CD38+) T lymphocytes in HIV-infected individuals (46.51 ± 17.54%) was significantly higher than in healthy donors (27.54 ± 14.12%, P value = 0.001) without any significant differences in HVEM expression. Even though the percentages of HSV-1 infected T lymphocytes between HIV-infected individuals (79.25 ± 14.63%) and healthy donors (80.76 ± 7.13%) were not different (P value = 0.922), yet HSV-1 production in HIV-infected individuals (47.34 ± 11.14 × 10³ PFU/ml) was significantly greater than that of healthy donors (34.17 ± 8.48 × 10³ PFU/ml, P value = 0.001). Moreover, HSV-1 virions were released extracellularly rather than being associated with the cells, and superinfection of HSV-1 at a multiplicity of infection (MOI) of 5 significantly decreased HIV production (P value < 0.001).

Effects of Acanthus ebracteatus Vahl on tumor angiogenesis and on tumor growth in nude mice implanted with cervical cancer

Purpose

The aim of this study was to examine the effects of the crude extract of Acanthus ebracteatus Vahl (AE) on tumor growth and angiogenesis by utilizing a tumor model in which nude mice were implanted with cervical cancer cells containing human papillomavirus 16 DNA (HPV-16 DNA).

Materials and methods

The growth-inhibitory effect of AE was investigated in four different cell types: CaSki (HPV-16 positive), HeLa (HPV-18 positive), hepatocellular carcinoma cells (HepG2), and human dermal fibroblast cells (HDFs). The cell viabilities and IC₅₀ values of AE were determined in cells incubated with AE for different lengths of time. To conduct studies in vivo, female BALB/c nude mice (aged 6–7 weeks, weighing 20–25 g) were used. A cervical cancer-derived cell line (CaSki) with integrated HPV-16 DNA was injected subcutaneously (1 × 10⁷ cells/200 μL) in the middle dorsum of each animal (HPV group). One week after injection, mice were fed orally with AE crude extract at either 300 or 3000 mg/kg body weight/day for 14 or 28 days (HPV-AE groups). Tumor microvasculature and capillary vascularity were determined using laser scanning confocal microscopy. Tumor tissue was collected from each mouse to evaluate tumor histology and vascular endothelial growth factor (VEGF) immunostaining.

Results

The time-response curves of AE and the dose-dependent effect of AE on growth inhibition were determined. After a 48-hour incubation period, the IC₅₀ of AE in CaSki was discovered to be significantly different from that of HDFs (P < 0.05). A microvascular network was observed around the tumor area in the HPV group on days 21 and 35. Tumor capillary vascularity in the HPV group was significantly increased compared with the control group (P < 0.001). High-dose treatment of AE extract (HPV-3000AE group) significantly attenuated the increase in VEGF expression and tumor angiogenesis in mice that received either the 14- or 28-day treatment period (P < 0.001).

Conclusion

Our novel findings demonstrated that AE crude extract could inhibit cervical cancer growth, VEGF expression, and angiogenesis in a CaSki-cell transplant model in mice.

Molecular and demographic analysis of respiratory syncytial virus infection in patients admitted to King Chulalongkorn Memorial Hospital, Thailand, 2007

Please cite this paper as: Boonyasuppayakorn et al. (2010) Molecular and demographic analysis of respiratory syncytial virus infection in King Chulalongkorn Memorial Hospital admitted patients, Thailand, 2007. Influenza and Other Respiratory Viruses 4(5), 313–323.

Objectives:  To preliminary preview the molecular character and its possible clinical correlation of RSV subgroups in Thailand.

Design:  Cross‐sectional analytic design.

Setting:  Admitted acute lower respiratory tract infection patients of King Chulalongkorn Memorial Hospital, Bangkok, during Jun–Dec, 2007 were recruited.

Sample:  Nasopharyngeal aspirations were collected.

Main outcome measures:  All samples were analyzed for the presence of RSV glycoprotein G gene by reverse transcription PCR. Molecular character of each subgroup was determined by sequencing. Admission records were also analyzed for clinical correlations.

Results:  Equal infectivity and severity of both RSV subgroups to the patients was shown. Mixed infection was shown to be as common as each single infection, higher than previously reported. GA2 of subgroup A and BA‐IV of subgroup B were the most widespread genotypes and showed their monophyletic origins. From admission records, either type of infection did not show significantly preference in demographic record or clinical severity. Comorbidity, however, was statistically significant that more congenital heart disease was found in negative RSV cases, while more chronic pulmonary disease was in positive cases. Nevertheless, the clinical severity was insignificantly different suggesting that only patients with chronic pulmonary underlying were prone to be infected with RSV.

Conclusions:  This preliminary RSV study showed prevalence of subgroups, types of infection, and common genotypes in an epidemic, uncorrelated to demography or clinical severity.

Mouse acquired HPV tumor using dorsal skin-fold window chamber

Human papillomavirus (HPV) plays important role in developing several types of cancer especially cervical cancer. In order to understand the viral pathogenesis, the animal model of HPV infection is very necessary. This communication reports establishment of an animal model carrying implanted HeLa cells, a human cervical cancer cell line via dorsal skinfold window chambers. Nude mice were divided into 4 groups; each group contained different amount of HeLa cells, 2.5 x 10(5), 5 x 10(5), and 1 x 10(6) cells, and cell free medium (control), respectively. The results showed that even using the low number of HeLa cells (2.5 x l0(5)), the tumor microvasculature was developed at 2 weeks after implantation with the enlarged tumor margin which then progressed to tumor mass in the following week. The existing tumor was confirmed to be HeLa-cell type by PCR, in situ hybridization, and HPV genotyping. By using linear regression analysis, it indicated that means of tumor size from each group significantly increased in relation to number of HeLa cells used (R2 = 0.98, y = 0.1171x + 4.35). This mouse model will be useful for the further HPV studies particularly anti-cancer drugs efficacy.

Acyclovir susceptibility of herpes simplex virus isolates at King Chulalongkorn Memorial Hospital, Bangkok

OBJECTIVE

To determine the ACV susceptibility in Thai HSV clinical isolates.

MATERIAL AND METHOD

One hundred thirty HSV isolates from the Virology Laboratory Unit, King Chulalongkorn Memorial Hospital, Bangkok Thailand had typing done by immunofluoresent assay using monoclonal antibody specific to either HSV-1 or HSV-2. Their sensitivity to ACV (IC50) was determined by plaque reduction assay.

RESULTS

The IC50 of 77 HSV-1 isolates ranged from 0.07-0.97 microg/ml and that of 53 HSV-2 isolates was 0.13-1.66 microg/ml. The standard HSV-1 (KOS) and HSV-2 (Baylor 186) were included in each run. The mean + standard deviation (SD) of ACV IC50 among HSV-1 and HSV-2 isolates were 0.38 +/- 0.23 and 0.50 +/- 0.32 microg/ml while that of standard HSV-1 and HSV-2 were 0.45 +/- 0.13 and 0.57 +/- 0.04 microg/ml. Statistically significant difference between IC50 of HSV-1 and HSV-2 isolates was indicated (p = 0.02).

CONCLUSION

No ACV(r) HSV has been detected and ACV susceptibility of HSV-2 has more resistance than that of HSV-1.

Prevalence of human cytomegalovirus (HCMV) gB genotypes in Thai patients

Human cytomegalovirus (HCMV) infection can cause asymptomatic to symptomic diseases leading to morbidity and mortality especially in immunocompromized patients. One factor of the difference in clinical outcome is the distinction of HCMV strain. As HCMV glycoprotein (g)B plays an important role in viral entry and neutralizing antibody induction, HCMV gB genotypes were determined in 161 clinical specimens containing HCMV-DNA obtained from patients at King Chulalongkorn Memorial Hospital, Bangkok, Thailand during the year 2000 and 2004. Of the 113 (70%) samples that were able to be genotyped, mixed gB genotype was demonstrated in 35%, followed by gB1 (33%), gB3 (15%), gB2 (11%), and untyped (7%); gB4 was not detected. The distribution of HCMV gB genotypes between genders was not significantly different. Mixed gB genotype (35%) was found in HIV- infected patients.

Intra- and intergenotypic variations among human cytomegalovirus gB genotypes

OBJECTIVES

To study genotypic variations among human cytomegalovirus (HCMV) gB genotypes in clinical samples of Thai patients.

METHODS

gB genotyping of 31 HCMV-DNA-positive clinical samples were determined by PCR-RFLP, gene cloning and DNA sequencing methods.

RESULTS

Eight gB1, 7 gB2, 7 gB3, 6 gB untype (UT1 and UT2) and 3 mixed gB genotypes were first identified by PCR-RFLP. All 3 mixed gB genotype samples and 1 gB2 sample were cloned and confirmed gB genotype by PCR-RFLP. Altogether, 57 strains (27 unique types and 30 transformants) were further analyzed by DNA sequencing method. Discordant results between PCR-RFLP and DNA sequencing methods were demonstrated in 5 samples and 1 clone. The gB UT1 and UT2 were all classified as gB1 except 1 sample of UT1 (9D), suggesting a new variant. Each genotype had a similarity of more than 97%, whereas strains of different genotypes had 77.71-92.75% homology. The most divergent type was gB3.

CONCLUSIONS

Intra- and intergenotypic variations among strains were demonstrated either in individual or distinct patients. Intragenotypic variation in a person occurs possibly due mainly to a point mutation mechanism rather than reinfection of a new gB genotype.

Increase of genital HSV-1 and mixed HSV-1 and HSV-2 infection in Bangkok, Thailand

From January 1998 to December 2004, 207 out of 1125 samples were HSV isolation positive and typed. Two groups of patients, Thai and foreigner, as well as site of infection, non-genital and genital area, were identified. The prevalence of non-genital HSV-1 infection from 27 samples of Thai patients was 81.84%. Out of 180 genital samples, 39.02% HSV-1 and 43.09% HSV-2 from 123 Thai patients and 36.84% HSV-1 and 49.12% HSV-2 of 57 foreigner patients were determined. Moreover mixed infection of HSV-1 and HSV-2 was found in both Thai and foreigner groups, 17.89% and 14.04%, respectively. The prevalence of genital HSV-1 infection in Thai patients chronologically increases from 1.6% to 56.91% from of 1985 to 2004. Increase of HSV-1 genital infection and mixed HSV-1 and HSV-2 infection in Thai people might probably be due to changing of sexual behavior in the AIDS era.

The prevalence of varicella-zoster virus infection in normal healthy individuals aged above 6 months

The prevalence of varicella-zoster virus (VZV) infection was studied by determining the presence of IgG antibody to VZV (anti-VZV IgG) using ELISA method. Three hundred and fifty sera collected from Thai healthy individuals aged above 6 months (mean age +/- standard deviation = 14.9 +/- 11.4) were tested, the prevalence of VZV infection was 64.6% (225/350). All samples were randomly sampling from healthy children and blood donors who visited the hospital and clssified into 7 groups, 50 samples each, according to their age, i.e., group 1; 6 months-3 years, group 2; 4-6 years, group 3; 7-9 years, group 4; 10-14 years, group 5; 15-19 years, group 6; 20-24 years and group 7; above 25 years. The prevalence of VZV infection were 12%, 42%, 64%, 70%, 78%, 84% and 100% respectively. The mean amount of anti-VZV IgG among groups of positive VZV infection (225 samples) was 86.8 +/- 29.7 unit/ml. The mean amount of anti-VZV IgG was highest in 6 months-3 years age group (113.6 +/- 39.2 unit/ml). Significant difference of the mean amount of anti- VZV IgG was found between group 1, 3, 6 and other groups (p-value < 0.05). There was a correlation between history of varicella and the presence of anti-VZV IgG in the serum. 95.3% of individuals with positive history has already had the antibody. The important associated factors that might involve VZV infection were age, number of members in family and place of exposure to VZV infection. Other factors, such as sex and income did not show any association to VZV infection.

Establishment of real-time polymerase chain reaction-based assay for quantitation of Epstein-Barr virus DNA in healthy donors and in patients with EBV associated lymphoma

Epstein-Barr virus (EBV) is associated with several malignancies including nasopharyngeal carcinoma and lymphoma in immunocompromised patients. Quantitative monitoring of EBV DNA in these patients has recently become essential for management of the disease. In the present study the authors developed a rapid and reliable real-time PCR to quantify the EBV DNA in peripheral blood mononuclear cell (PBMC) using hybridization probe technique. The real-time primers and probes in this real-time PCR system were designed based on EBNA-1 sequence. The newly-established real-time PCR demonstrated its high sensitivity (as few as 10 copies of EBV could be detected) and specificity. The intra- and inter-assay variations of the assay were shown to be within a 0.5-log10-difference range. A total of 2 EBV-seronegative, 14 EBV-seropositive healthy donors and 4 patients with PCNSL were enrolled into the study. Our results revealed the median of EBV-DNA in lymphoma patients (7886 copies/10(6) PBMC or 15,150 copies /microg DNA) was higher than that of healthy donors (<10 copies/l0(6) PBMC or <10 copies/microg DNA) with statistic significance (P < 0.01). Assessment of this assay in larger number of donors and patients will provide clinical cut-off values which are essential for monitoring and diagnosis of EBV-associated diseases.

Intratypic variations among Thai herpes simplex virus (HSV) isolates determined by restriction fragment length polymorphism (RFLP) analysis

Whole genomic polymorphisms for 20 HSV-1 and 20 HSV-2 isolates from Thai patients were analyzed by means of Restriction Fragment Length Polymorphism (RFLP) analysis using 4 restriction endonucleases: BamHI, Kpnl, HindIII, and EcoRI. Variations in cleavage sites among the HSV-1 and HSV-2 isolates were compared to the cleavage patterns of standard HSV-1 strain KOS and HSV-2 strain Baylor 186. Although 70% of HSV-1 isolates with BamHI digestion, 50% with Kpnl, 75% with HindIII and 70% with EcoRI digestion were found to be similar to the standard HSV-1 (KOS) pattern, new BamHI restriction sites were detected in some HSV-1 isolates. For HSV-2 isolates, 85% had the same pattern as the standard HSV-2 (Baylor 186) after digestion with BamHI, HindIII, and EcoRI. No difference was observed with Kpnl digestion. When the patterns from the 4 enzymes were combined, HSV-1 isolates showed more divergence than the HSV-2 isolates. HSV-1 isolates found in both non-genital and genital lesions had more variety than the HSV-2 isolates. This suggests that intratypic variations in HSV-2 are fewer than in HSV-1.

LipL32, an outer membrane protein of Leptospira, as an antigen in a dipstick assay for diagnosis of leptospirosis

Microscopic agglutination test (MAT), as well as other serological assays that aimed at detecting antibodies to Leptospira, supplements the leptospirosis diagnosis based on the clinical features. Nevertheless, false positive results have been occasionally reported when the crude antigen was used in those antibody-based tests due either to the presence of antibodies stimulated by other antigenically related pathogens in the patient's serum, or the antibodies in the serum may be stimulated by a previously unrecognized Leptospira infection, especially in the disease endemic areas. Thus, the more refined antigen should improve the serodiagnostic accuracy. Among Leptospira spp., LipL32, which is a pathogenic Leptospira outer membrane protein (OMP), expressed by the bacteria grown both in vitro and in vivo. In this study, recombinant LipL32 protein was tested by a dipstick method for its potential in serodiagnosis of leptospirosis. Preliminary results suggest that the recombinant LipL32 is a good diagnostic detection reagent for specific Leptospira IgG. Diagnostic sensitivity and specificity of the Lip32 dipstick assay, when compared to those of MAT, were 100% and 98.33%, respectively.

Antiangiogenic activity of curcumin in hepatocellular carcinoma cells implanted nude mice

Antiangiogenic activity of curcumin on the tumor neogenesis was investigated by evaluating the density of neocapillaries induced by Hepatocellular carcinoma cells (HepG2) in mice, using intravital fluorescence videomicroscopy. Male BALB/c nude mice (20-25 g) were used, and a dorsal skin-fold chamber was implanted. HepG2 (30 microl of 2 x 10(6) cells) were inoculated on the upper surface of the skin within the chamber. The mice were divided into two groups as follows. Dimethyl sulfoxide solution (0.1%) was fed (HepG2 group, n=5) or curcumin solution (3000 mg/kg bw) was fed oral daily (HepG2-Cur group, n=5), one day after the inoculation of HepG. On days 7 and 14 post-tumor-inoculation, the tumor microvasculature was visualized by injecting 0.1 ml of 0.5% rhodamine B isothiocyanate-labeled dextran intravenously, and observed under an intravital fluorescence videomicroscope. Based on the recorded videoimage, the tumor neocapillary density and microvasculature were evaluated using a digital image analysis and correlated with the tumor area. The image analysis demonstrated that in the HepG2-group the neocapillary densities were significantly increased on day 7, and day 14, compared to the aged-matched Sham-group (P<0.05). In the HepG2-Cur group, the increase of tumor neocapillary density was attenuated significantly. It was suggested that high dose of curcumin might be an effective anti-angiogenic drug in the treatment against tumor.

Prevalence of dengue virus in Aedes mosquitoes during dry season by semi-nested reverse transcriptase-polymerase chain reaction (semi-nested RT-PCR)

Dengue hemorrhagic fever remains a major health concern in Thailand. Much effort has focused on the prevention and control of the disease. Detection of dengue virus infection rate in mosquitoes would evaluate dengue control programs and predict the epidemics of dengue hemorrhagic fever. To determine dengue virus infection rate in mosquitoes by Semi-nested RT-PCR. A total of 400 mosquitoes were collected from Rom Kao Community representing a crowded community and another 9 non-crowded communities in Bangkok. Mosquitoes were then divided into 40 pools, each contained 10 mosquitoes. A total of 391 Aedes aegypti and 9 Aedes albopictus were screened for dengue virus. The mosquito infection rate in the Rom Klao community was 5% of the mosquito pool equal to that found in non-crowded communities. Both groups were found to have dengue virus serotype 3. The present study suggests a circulation of dengue virus serotype 3 in both crowded and non-crowed communities, the infection rates of which are indifferent during the dry season.

Establishment of cytotoxic T lymphocytes specific for autologous Epstein-Barr virus in HIV-infected patients: the feasibility study of EBV-specific immunotherapy for patients with EBV-associated lymphoma

Cytotoxic T lymphocytes specific for Epstein-Barr virus (EBV) have previously been successfully used in immunotherapy of Posttransplant lymphoproliferative disease (PTLD) and Hodgkin's disease. A similar strategy has never been employed in HIV/AIDS patients who also have high risk of developing EBV-associated lymphoma. A total of 5 HIV-infected patients were enrolled to evaluate their EBV-specific T cell responses by Interferon-gamma (IFNgamma) ELISpot assays. Most patients had detectable T cell responses, mainly directed at Epstein-Barr nuclear antigen (EBNA-3). The authors wanted to see whether it was possible to augment magnitude and spectrum of the EBV responses by stimulating patient PBMC with cells presenting autologous EBV antigens. The authors successfully established spontaneously EBV-transformed lymphoblastoid cell lines (EBVh-BCL) and used them for generation of EBV-specific CTL (EBV-CTL). The EBVh-CTL lines established in the present study were not only highly cytotoxic against the autologous virus but also able to secrete IFNgamma detected by ELISpot. The authors are now in the process of generating these lines in a large number and in a clinical grade for adoptive immunotherapy.

Induction of apoptosis by herpes simplex virus in Jurkat cells is partly through caspase-3, -8 and -9 activation

Herpes simplex virus (HSV), a large DNA containing virus, is endemic in all human populations investigated. After infection of mucocutaneuos surfaces, HSV establishes a latent infection in nerve cells. Various immune evasion mechanisms have been shown to be utilized by HSV including apoptosis induction in Tlymphocytes. However, the mechanisms of T cell infection and apoptosis by HSV are still unknown. The present study investigated the molecular mechanisms of apoptosis induction in T cells by HSV The Jurkat T cell line was used as a representative for T cells. Apoptosis detection by Annexin Vassay demonstrated that both HSV-1 and HSV-2 induced apoptosis in Jurkat cells and caspase-3, -8, and -9 inhibitors blocked apoptosis induced by HSV-1 and HSV-2. The data suggested that HSV-1 and HSV-2 induced apoptosis in T lymphocytes by caspase-dependent pathway. However, apoptosis may occur through other mechanism(s) since caspase inhibitors used in the present study could not completely inhibit apoptosis induced by HSV infection. In addition, the data demonstrated that the number of apoptotic cells induced by HSV-2 was significantly higher than byHSV-1 at 12 hour post-infection (h p.i.) (p = 0.003). Further studies in peripheral blood T cells and the proteins of viruses involved in apoptosis induction should be further performed in order to elucidate the molecular mechanisms of apoptosis induced by these viruses.

Orangutan herpesvirus

A male orangutan suffered from ulcers at the buccal mucosa. We obtained swab fluid from the base of both vesicles and ulcers and collected blood for further separation into serum, plasma and peripheral blood mononuclear cells (PBMC) for detection of antibody to herpesvirus by serology and herpesvirus DNA by polymerase chain reaction (PCR) using consensus degenerate primers. Serology was positive for human EBV IgG but negative for Epstein-Barr virus (EBV) immunoglobulin (IgM), as well as for both human cytomegalovirus and herpes simplex virus IgG and IgM. Upon PCR, we obtained a 232-bp product of virus DNA from PBMC, but not from lesions, serum or plasma. We confirmed the positive result by direct sequencing and compared the nucleotide sequence with other nucleotide sequences applying the BLAST program from GenBank. The sequence was similar to lymphocryptovirus of macaque (93%), marmoset (93%), gorilla (90%) and human EBV (90%). We aligned this sequence with other sequences in GenBank and performed phylogenetic analysis, showing that it probably belongs to the gammaherpesvirus group.

Increased Susceptibility of Herpes simplex Virus-1 Growth in Phytohemagglutinin-Activated T Lymphocytes Caused by Upregulation of Herpesvirus Entry Mediator A mRNA Expression

OBJECTIVES

To study herpes simplex virus (HSV) growth in human T lymphocytes (Jurkat cells) with and without phytohemagglutinin (PHA) activation and to investigate the possible mechanism of viral growth.

METHODS

The levels of HSV-1 production and adsorption were determined by plaque titration assay. The number of HSV-1-infected cells was assayed using flow cytometry. The expression of herpesvirus entry mediator A (HveA) mRNA was detected by RT-PCR.

RESULTS

HSV-1 production as well as the number of HSV-1-infected Jurkat cells were enhanced after the cells were activated by PHA. Moreover, the amount of viral entry was demonstrated to increase in PHA-activated cells. An increase in HveA mRNA was observed in PHA-activated Jurkat cells.

CONCLUSIONS

We found that HSV-1 can replicate in human T lymphocytes, and the replication was increased following PHA activation. This finding may be due to an increase in viral entry via HveA receptor.

Human herpes virus 6 antibodies in beta-thalassemia/hemoglobin E pediatric patients

Human herpesvirus 6 (HHV-6) is a viral pathogen that causes exanthem subitum in children. It has also been identified as the cause of life-threatening illness in immunocompromised pediatric patients and transplant recipients. We undertook a serological study of HHV-6 IgM and IgG antibody among 29 children (12 females and 17 males) with beta-thalassemia/HbE disease. The rate of infection was 86.2%; the rates of early recent infection (IgM positive only), recent infection (both IgM and IgG positive) and past infection (IgG positive only) were 13.8%, 41.4% and 31.0%, respectively. The geometric means of the IgM and IgG titers of the splenectomy group (9 cases) were 10.15 units and 11.18 units, respectively. The geometric means of the IgM and IgG titers of the non-splenectomy group (20 cases) were 10.10 units and 12.84 units, respectively. According to this study, the prevalence of HHV6 infection among pediatric patients with beta-thalassemia/HbE is very high; morever, the significantly higher titer among these patients may imply a high risk for further possible bone marrow transplantation. Increased awareness of HHV-6 infection among this population is necessary.

Seroprevalence of anti-RSV IgG in Thai children aged 6 months to 5 years

Respiratory syncytial virus (RSV) is the single most important cause of lower respiratory tract infection during infancy and early childhood worldwide including Thailand. The magnitude as well as the intensity of both infection and host response to the RSV infection determine the severity of disease. To determine the presence of anti-RSV IgG in children of different age groups, 124 serum samples were randomly collected from healthy children aged 6 months to 5 years. All of them were assayed for anti-RSV IgG using a commercial ELISA kit. The mean prevalence rate was found to be 68.91%. The prevalence increased with age: from 6 to 11 months, 11.76%; from 12 to 17 months, 41.67%; from 18 to 23 months, 60.87%; from 24 to 29 months, 88.24%; from 30 to 35 months, 78.57%; from 36 to 41 months, 94.44% and from 42 to 60 months, 100%. The amount of anti-RSV IgG among the groups was significantly different (p = 0.006). No sexual preponderance was found. RSV infection commonly occurred in children aged 12 to 29 months. All children older than 5 years had experienced a RSV infection.

Rectal prolapse associated with cytomegalovirus pseudomembranous colitis in a child infected by human immunodeficiency virus

We report a newly recognized presentation of cytomegalovirus (CMV) enterocolitis in a 4-year-old girl with newly diagnosed HIV disease who presented with rectal prolapse. Gross findings showed multiple whitish punctate lesions. An endoscopic examination revealed multiple shallow ulcers and pseudomembranes along the colon. A biopsy from colonic tissues demonstrated CMV-like inclusion bodies. A direct immunofluorescence assay using specific CMV monoclonal antibody was positive for CMV-infected cells in specimens from the rectal smear.

Prevalence of parvovirus B19 infection in Thai young adults

The prevalence of antibody to human parvovirus B19 in 128 Thai healthy young adults was measured. Antibodies of the immunoglobulin G (IgG) class were investigated in serum samples of 51 males and 77 females aged 18-24 years (mean 19.83; SD 1.07) by a commercial enzyme-linked immunosorbent assay (ELISA) using high specific recombinant parvovirus B 19 antigen. Only 14 out of 128 (10.94%) sera were found positive, including 6 males and 8 females. No sex preponderance was observed. The amount of antibody calculated as antibody index was not statistically significant difference between genders.

Seroprevalence of cytomegalovirus infection in children born to HIV-1 infected women

Cytomegalovirus (CMV) is a frequent opportunistic infectious agent in children infected with human immunodeficiency virus type 1 (HIV-1). It has been implicated as a factor in the progression of HIV-1 disease. The aim of the present study was to evaluate the prevalence of CMV infection in Thai children born to HIV-1 infected women. The prevalence of CMV infection was 13, 89 and 84% in HIV-infected children and 9, 61 and 75% in HIV uninfected at age ranges of 0-12, 13-36 and 37-79 months, respectively. The prevalence of CMV infection was significantly different between HIV infected children (89%) and HIV uninfected (61%) at the age of 13-36 months (p < 0.05). The presence of CMV IgM in some children of age < 1 year suggested that CMV infection could occur early in life. Early co-infection may be important as they remain a risk factor for reactivation of latent CMV infection throughout the course of the HIV diseases. Clinical monitoring and appropriate work up may be of benefit in the early diagnosis and treatment of CMV disease.

Risk factors for conjunctival squamous cell neoplasia: a matched case-control study

AIMS

To identify roles of human papillomavirus (HPV) infection and solar elastosis as the risk factors for conjunctival squamous cell neoplasia (CSCN).

METHODS

30 consecutive pathological specimens, ranging from conjunctival intraepithelial neoplasia, carcinoma in situ, to invasive squamous cell carcinoma were retrieved from tissue archives. 30 controls were disease free conjunctiva from age and sex matched patients undergoing extracapsular cataract extraction. Two masked pathologists studied haematoxylin and eosin stains on paraffin embedded conjunctival tissues. Elastic stain for solar elastosis was blindly interpreted in comparison with negative and positive controls. HPV infection was studied by polymerase chain reaction and dot hybridisation.

RESULTS

The mean age of CSCN patients was 54.9 years. The male to female ratio was 1:1. Solar elastosis was seen in 53.3% of CSCN and in 3.3% of controls with an odds ratio of 16.0 (95% CI, 2.49 to 670.96; p value = 0.0003). HPV DNA were not detected in any of the specimens.

CONCLUSION

Solar elastosis is much more frequently found in CSCN cases than in their matched controls and is a risk factor for CSCN. These data are insufficient to conclude that HPV infection is a risk factor for CSCN.

Hemodynamic profiles of patients with dengue hemorrhagic fever during toxic stage: an echocardiographic study

OBJECTIVE

To study left ventricular performance and hemodynamic abnormalities during different stages of dengue hemorrhagic fever (DHF).

DESIGN AND SETTING

Observational study in a tertiary medical school hospital.

PATIENTS

Twenty-four patients with serologically confirmed diagnosis of dengue virus infection and DHF according to the WHO criteria.

METHODS

Echocardiography was performed during toxic, convalescent stages and at least 2 weeks after discharge (recovery). Left ventricular ejection fraction, rate-corrected velocity of circumferential fiber shortening adjusted for end-systolic meridional wall stress (VCFC/ESS) Z score, end-diastolic volume Z score, cardiac index, heart rate, mean arterial pressure, and total systemic vascular resistance (SVR) were compared between different stages of DHF.

RESULTS

Ejection fraction and VCFC/ESS were significantly lower during the toxic stage than after recovery. End-diastolic volume was low during toxic stage and returned to normal during convalescence and recovery. Cardiac index was low during the toxic stage due to decreased preload (low end-diastolic volume) and depressed left ventricular ejection fraction. Cardiac index remained subnormal during convalescence due to sinus bradycardia. Wide variation in heart rate during toxic stage resulted in a small, nonsignificant increase compared to recovery. With treatment, heightened SVR resulted in relatively normal mean arterial pressure throughout the course of the illness.

CONCLUSIONS

The mechanism of decreased cardiac output during toxic stage of DHF is complex. Decreased preload is accompanied by decreased left ventricular performance, and possibly a subnormal heart rate response in some patients.

Detection and differentiation of human herpesviruses 1-5 by consensus primer PCR and RFLP

Eight human viruses of the Herpesviridae family represent a significant public health problem world-wide. Detection and typing of five of the human herpesviruses (HSV-1, HSV-2, VZV, EBV, and CMV) was performed by applying a consensus primer polymerase chain reaction (PCR). The amplified PCR products from the five human herpesviruses were typed based on their restriction enzyme digestion polymorphism with Hinf I and Alu I. Fifteen clinically suspected specimens from herpesvirus-infected patients were also evaluated. A fragment of the DNA polymerase gene from each of the five human herpesviruses was successfully amplified by the set of consensus primers. Their amplicons obtained by PCR from the template DNAs were subjected to restriction endonuclease digestion and human herpesviruses 1-5 could be clearly differentiated and typed. This method can be used to detect and differentiate between the five human herpesviruses in clinical specimens. This study demonstrates the value of testing for five human herpesviruses by consensus PCR and restricted fragment length polymorphism (RFLP). These procedures are simple and straightforward techniques for the investigation of clinical specimens.

Molecular epidemiology of gibbon hepatitis B virus transmission

Although transmission of human hepatitis B virus (HBV) variants to nonhuman primates is well documented, it remains to be elucidated whether nonhuman primate HBV is transmissible to humans. The prevalence and transmission routes of gibbon HBV were analysed in 101 captive gibbons in Thailand. Approximately 40 % of these animals showed at least one marker of HBV infection; 19 animals were chronic HBV carriers, characterized by elevated levels of alanine amino transferase and the presence of HBV DNA. Some of the chronic animals were found to be anti-HBc (HBV core antigen) negative (4 of 19), while precore promoter point mutations (nt 1762 or 1764) were determined in four animals by RFLP analysis. Phylogenetic tree analysis of the complete surface gene sequences revealed that gibbon viruses clustered separately from hepadnaviruses of other hosts. Evidence for horizontal and vertical transmission in captive gibbons was obtained. HBV DNA was also detected in the saliva of HBV carrier gibbons. Although some of the animal caretakers at the Krabok Koo Wildlife Breeding Centre were found to be chronic HBV carriers, genotype and sequence analysis did not reveal any evidence for zoonotic disease transmission.

Endothelial nitric oxide synthase expression in systemic and pulmonary circulation of streptozotocin induced diabetic rats: comparison using image analysis

To compare the level of endothelial nitric oxide synthase (eNOS) expression produced in heart and lung vascular tissue, the protein content was determined using Western blot analysis with the enhancement of image processing. Heart and lung extracts from 12 and 24 weeks from control (CON) and streptozotocin-induced diabetic (DM) rats were collected for Western blot analysis. Using monoclonal antibody against rat eNOS protein (140 kDa), the eNOS-protein bands were detected with enhanced chemiluminescence (ECL; Amersham) and exposured to film (Hyperfilm-ECL; Amersham). Images of eNOS bands on each film were then scanned and saved to digital files. Using Global Lab Image software, the number of pixels in each digital file was counted and calibrated for eNOS-protein content. For the CON and DM groups, the mean values of eNOS-protein contents were calculated and expressed as a percentage of total protein content, 5 micrograms. It was found that the eNOS level in DM hearts was significantly decreased, as compared to age-matched CON hearts. On the other hand, eNOS levels in DM lungs was increased, compared to CON lungs. Therefore, it may be concluded that high, not low, flow-mediated eNOS expression is a good measure of hyperglycemic-induced endothelial dysfunction.

Replication of herpes simplex virus in T lymphocytes

HSV is known to cause infection at various parts in the human body such as skin, mouth, eyes, genital area, and brain. In this study, the authors showed the possibility of HSV replication in Jurkat, a human leukemic T lymphocytes. Although the yield production was very low when compared to the other 2 epithelial cells, Vero and HEp-2 cells, the yield production could enhance after PHA activation. Delayed viral protein expression was observed in Jurkat cells. This might be the reason for low production. However, the exactly mechanism is unknown. Replication of viruses have been examined in a number of cell systems and the duration of successive steps in the replication cycle depends upon the types of cells, the virus strain, and the multiplicity of infection.

Survey of human papillomavirus infection in cervical intraepithelial neoplasia in Thai women

HPV infection is known to be associated with cervical cancer development. Precancerous lesions named cervical intraepithelial neoplasia (CIN) are divided into 3 grades, i.e., CIN-1, CIN-2, and CIN-3. Here, HPV infection determined by PCR and dot hybridization was observed in these 3 different grades of formalin-fixed paraffin embedded tissues. The HPV infection was demonstrated in 33.3 per cent of CIN-1, 36.8 per cent of CIN-2 and 75 per cent of CIN-3. Using type specific probes for HPV-6, 11, 16, 18 and 33, HPV-16 was the most prevalent type (44.44%) followed by HPV-18 (16.05%) in CIN-3. Only one HPV-18 was identified in CIN-1 while CIN-2 contained one HPV-6 and one HPV-18. Mixed infection was found in CIN-3 (12.35%). All of them had HPV-16. The cervicitis cases with normal histopathology were included as control. Only 2.7 per cent of HPV infection was shown. The relative risk of HPV infection was high in CIN-3 (OR = 107.25, 95% CI = 50.29-228.73). Our data confirm the association between high-risk HPV types and development of CIN.