Association of sexually transmitted infections and human papillomavirus co-infection with abnormal cervical cytology among women in Saudi Arabia.

Human papillomavirus (HPV) is a causative agent of cervical and other cancers. Sexually transmitted Infections (STIs) may play a crucial role in HPV persistence, leading to serious complications, including cervical cancer. This study investigated the association of HPV/STI co-infection in cervical samples with cervical dysplasia among women in Saudi Arabia. HPV-positive cervical samples (n = 142) were obtained from previous studies and newly collected samples (n = 209) were obtained from women aged 19-83 years. For HPV detection and genotyping, PCR and Genoflow HPV assay kits were used. STIs were detected using a Genoflow STD array kit. Of 351 samples, 94 (27%) were positive for STIs. Among HPV-positive samples, 36 (25%) were positive for STIs; the most common pathogens were Ureaplasma urealyticum/Ureaplasma parvu (13%) and Mycoplasma hominis (6%). A global significant correlation was detected between HPV and STIs with progression of abnormal cervical cytology (χ2 = 176, P < 0.0001). Associations between cervical cytology diagnosis and HPV status, STI types (opportunistic and pathogenic), and the presence of Ureaplasma spp., and Mycoplasma hominis were significant (P < 0.05). Our results suggest that additional study in a larger population is warranted to determine the association between HPV/STI co-infection and cervical neoplasia in Saudi women.

Human papillomavirus type 16 and 18 viral loads as predictors associated with abnormal cervical cytology among women in Saudi Arabia.

The detection of HPV viral DNA is regularly conducted with cervical screening. However, using a molecular marker such as the viral load may serve as a predictor associated with disease detection and progression. The present study aimed to screen for and genotype HPV among women in Saudi Arabia, develop and validate sensitive quantitative polymerase chain reaction (qPCR) assays to detect viral load for the two most common HPV types, namely 16 and 18, and assess whether HPV viral load could be used as a marker for cervical abnormality and disease progression. This study examined 733 specimens (both formalin-fixed paraffin embedded specimens and PAP smear samples) from women who underwent cervical screening. The specimens and samples were processed for DNA extraction and then tested for HPV DNA using nested PCR. Approximately 165 specimens (18%) were positive for HPV. Those specimens were genotyped using a reverse line blotting hybridization assay. The results indicated that the most common HPV types detected were a single infection with HPV 16 (51%) or with HPV 18 (28%) followed by infections with multiple HPV types (~7%). A qPCR TaqMan assay developed and validated in-house was used to determine viral load for HPV genotypes 16 (n = 80) and 18 (n = 45). Viral loads for both HPV types were significantly associated with cervical cytology grade (P < 0.05). The odds ratio (OR) for the HPV 16 viral load was high for specimens with cervical cancer (OR, 18.8; 95% CI, 4.3-82.9) or for those with high-grade squamous intraepithelial lesions (OR, 14.7; 95% Cl, 2.43-88.49). For the HPV 18 viral load, the OR was significant only for specimens with cervical cancer (OR, 11.1; 95% Cl, 2.2-54.9). Logistic regression models for HPV 16 and for HPV 18 viral load levels were significant, with higher viral load associated with cervical abnormalities. These findings indicate that viral load is a predictor significantly associated with cytology abnormality in women who are positive for high-risk HPVs and suggest that integrating a viral load test into current clinical screening practices for HPV-positive women is warranted in Saudi Arabia.

Association of single nucleotide polymorphisms in microRNAs with susceptibility to hepatitis B virus infection and HBV-related liver complications: A study in a Saudi Arabian population.

The aim of this study was to evaluate the association of 10 SNPs in different microRNAs (miRNAs) with susceptibility to hepatitis B virus (HBV) infection, HBV clearance, persistence of chronic HBV infection, and progression to liver cirrhosis and hepatocellular carcinoma (HCC). Patients were categorized into the following groups: inactive HBV carrier, active HBV carrier, HBV-cleared subject and cirrhosis+HCC. Samples were analysed for 10 SNPs in microRNAs using either PCR-based genotyping or the TaqMan assay. We found that rs1358379 was associated with susceptibility to HBV infection, HBV clearance, persistent chronic HBV infection and liver cirrhosis+HCC. In addition, we found that rs2292832 and rs11614913 were associated with risk of HBV infection, viral clearance and cirrhosis+HCC, whereas rs2910164 was associated with proneness to HBV infection, and ability to clear the virus. There was evidence of associations between rs6505162 and HBV clearance and the development of liver disease, whereas a single association was found between rs2289030 and HBV clearance. Similarly, rs7372209 and rs4919510 were specifically associated with the development of HBV-induced liver complications. SNPs in miRNAs affect the susceptibility, clearance and progression of HBV infection in Saudi Arabian patients. We found, using Gene Ontology or pathway analyses, that these genes may contribute to the pathophysiology of HBV infection and related liver complications. However, differences in the association of examined SNPs with various clinical stages indicate variations in the respective functional roles of these polymorphisms and their miRNAs, and thus, further investigation to fully explore their therapeutic potential is warranted.

Case characteristics among Middle East respiratory syndrome coronavirus outbreak and non-outbreak cases in Saudi Arabia from 2012 to 2015.

OBJECTIVES: As of 1 November 2015, the Saudi Ministry of Health had reported 1273 cases of Middle East respiratory syndrome (MERS); among these cases, which included 9 outbreaks at several hospitals, 717 (56%) patients recovered, 14 (1%) remain hospitalised and 543 (43%) died. This study aimed to determine the epidemiological, demographic and clinical characteristics that distinguished cases of MERS contracted during outbreaks from those contracted sporadically (ie, non-outbreak) between 2012 and 2015 in Saudi Arabia. DESIGN: Data from the Saudi Ministry of Health of confirmed outbreak and non-outbreak cases of MERS coronavirus (CoV) infections from September 2012 through October 2015 were abstracted and analysed. Univariate and descriptive statistical analyses were conducted, and the time between disease onset and confirmation, onset and notification and onset and death were examined. RESULTS: A total of 1250 patients (aged 0-109 years; mean, 50.825 years) were reported infected with MERS-CoV. Approximately two-thirds of all MERS cases were diagnosed in men for outbreak and non-outbreak cases. Healthcare workers comprised 22% of all MERS cases for outbreak and non-outbreak cases. Nosocomial infections comprised one-third of all Saudi MERS cases; however, nosocomial infections occurred more frequently in outbreak than non-outbreak cases (p<0.001). Patients contracting MERS during an outbreak were significantly more likely to die of MERS (p<0.001). CONCLUSIONS: To date, nosocomial infections have fuelled MERS outbreaks. Given that the Kingdom of Saudi Arabia is a worldwide religious travel destination, localised outbreaks may have massive global implications and effective outbreak preventive measures are needed.

Sociodemographic characteristics and sexual behavior as risk factors for human papillomavirus infection in Saudi Arabia.

OBJECTIVES: To determine the prevalence and the sociodemographic characteristics and sexual behavior risk factors for human papillomavirus (HPV) infection in a hospital-based cohort of women in Saudi Arabia. METHODS: Cervical specimens and questionnaire data were collected from women attending clinics in Riyadh, Saudi Arabia. Cervical specimens were examined for abnormal cytology using a standard Pap test and for the presence of HPV-DNA using PCR and reverse line blot hybridization tests. RESULTS: Approximately 73% of the 400 women tested were Saudi nationals. Nearly 50% were under 40 years old (range 22-80 years, mean±standard deviation 41.20±10.43 years). Approximately 17% of the women were HPV-positive. The most commonly detected HPV types were HPV-18 (34%) and HPV-16 (19%), with multiple infections detected in 10% of positive specimens. Multivariate analyses revealed that smoking and multiple partners were significant risk factors for HPV infection (p<0.01). CONCLUSIONS: Because of societal challenges and an unsubstantiated assumption of low HPV prevalence, few studies have examined sociodemographic characteristics or sexual behaviors associated with HPV in Saudi women. However, a high prevalence of HPV infection was found, with smoking and multiple partners as significant risk factors, in this hospital-based cohort of predominantly Saudi women.

Hepatitis C virus genotype 1: how genetic variability of the core protein affects the response to pegylated-interferon and ribavirin therapy.

Hepatitis C virus subgenotypes 1a and 1b are found worldwide and cause 60% of all hepatitis C cases. It has been reported recently that viral genetic variations have a critical impact on the patient treatment outcome. In particular, polymorphisms of the HCV core protein have been linked to poor treatment response. However, most of these studies were conducted on Asian populations, Japanese in particular who are infected with HCV subgenotype 1b. Hence, we aimed in this study to examine the core protein polymorphisms in Saudi patients who are infected with chronic HCV genotype 1 (1a and 1b subtypes) and its association with treatment outcome. Direct sequencing of full-length core protein and data mining analyses were utilized. Results have shown that the response to treatment is dependent on subgenotypes. Indeed, HCV-1b showed different point mutations that are associated with treatment outcome where the point mutations at positions 70 (Arg(70) Gln) and 75 (Thr(75) Ala) in HCV-1b are significantly associated with PEG-IFN/RBV treatment response. In contrast, HCV-1a showed no significant association between core protein mutations and response to treatment. In addition, analyses of HCV-1a core protein sequences revealed a highly conserved region especially in the responder group. This study provides a new insight in the genetic variability of full-length core protein in HCV genotype 1 in Saudi infected patients.

Characterization of Enterococcus faecium isolates and first report of vanB phenotype-vanA genotype incongruence in the Middle East.

We aimed to characterize the vancomycin genotype/phenotype, carriage of putative virulence genes, and genetic relatedness of Enterococcus faecium isolates in Saudi Arabia. E. faecium isolated from inpatients at our medical center were studied. Sensitivity to ampicillin, linezolid, teicoplanin, quinupristin/dalfopristin, tetracycline, and ciprofloxacin was determined. The presence of van genes and virulence genes for aggregation substance (Asa-1), enterococcal surface proteins (esp), cytolysin (cylA, cylL, cylM), gelatinase (gelE), E. faecium endocarditis antigen (EfaA( fm )), hyaluronidase (hyl), and collagen adhesion (Ace) was assessed. Genetic relatedness was determined by pulsed-field gel electrophoresis (PFGE). Twenty-nine E. faecium isolates were obtained and the majority of isolates (n/N = 22/29) were from stool specimens. PFGE analysis identified eight pulsotypes (A-H) based on 80 % similarities. Isolates were represented in five major pulsotypes: type A (n = 5), type B (n = 3), type D (n = 6), type E (n = 5), and type F (n = 7). All isolates were vanA gene-positive. Thirteen isolates had vanA(+)/vanB(+) genotype. Of these, ten exhibited a vanB phenotype and three had a vanA phenotype. Eight isolates with vanA(+)/vanB(-) genotype exhibited vanB phenotype. Six of these eight isolates belonged to the same pulsotype. All isolates were positive for gelE, esp, and EfaA( fm ) genes. Five were CylA-positive and 24 had the hyl genes. Of the eight isolates harboring a combination of gelE, esp, EfaA( fm ), and hyl genes, five showed vanB phenotype-vanA genotype incongruence. This is the first report of vanB phenotype-vanA genotype incongruent E. faecium in the Middle East region. Molecular typing indicates clonal spread and high occurrence of virulence genes, especially esp genes, associated with epidemic clones.

The epidemiology of the first described carbapenem-resistant Klebsiella pneumoniae outbreak in a tertiary care hospital in Saudi Arabia: how far do we go?

The purpose of this investigation was to describe the first documented carbapenem-resistant Klebsiella pneumoniae (CRKP) outbreak in a tertiary care facility in Saudi Arabia. We initiated a prospective study to follow all cases of CRKP as well as the active surveillance of patients in areas where cases were identified. We also conducted a retrospective review of the microbiology database for any missed cases of CRKP. Pulsed field gel electrophoresis (PFGE) was conducted for the available CRKP isolates. During March 2010, a cluster of eight CRKPs was detected primarily in the adult intensive care unit (ICU). Patients with CRKPs were put under strict contact isolation, along with appropriate infection control measures. A retrospective review of K. pneumoniae isolates over the previous 6 months revealed two more CRKPs. The PFGE results during the outbreak period showed that the majority of strains were genetically indistinguishable or closely related. The majority of patients had prolonged hospital stay (91%), indwelling devices (81%), surgical procedures (74%), carbapenem use (62%), and colonization/infection with other multiple drug-resistant organisms (MDROs) (57%). Two-fifths of patients with CRKP had clinical infection and 38% died during the current hospitalization. Contact isolation, hand hygiene, environmental cleaning, and staff education may control CRKP outbreak in the acute care setting, but did not prevent endemicity.

Typing of human cytomegalovirus clinical isolates from Saudi patients by PCR-RFLP.

BACKGROUND: Information on strain types of human cytomegalovirus (HCMV) isolates from Saudi Arabian patients is lacking. MATERIALS AND METHODS: 80 clinical isolates of HCMV from Saudi Arabian patients were analyzed by PCR amplification of three regions (DNA polymerase, glycoprotein B, and glycoprotein H) of the virus genome. The resultant amplicons (2.0-2.7 kb) were further studied by restriction fragment length polymorphism (RFLP) using four enzymes (HaeIII, HhaI, MspI, and RsaI). RESULTS: Combined analysis of the cleavage patterns generated by the enzymes identified five strains, S1-S5, and several mixed and unique strains. 18 isolates belonged to S1 strain and were similar to laboratory strain AD169. Eight isolates were present in each of S2 and S3 strains. Six isolates and four isolates were found in S4 and S5 strains, respectively. 12 isolates contained a mixture of S3 and S5, which may have resulted from a dual infection. Each of the 24 remaining isolates had a different strain pattern. CONCLUSION: Our findings show that 80 HCMV clinical isolates were distributed into 30 different strains using PCRRFLP analysis of multiple viral subgenomic regions. However, the number of isolates is not uniformly distributed among strains (p < 0.02).

Peginterferon alpha-2b plus ribavirin compared with interferon alpha-2b plus ribavirin for initial treatment of chronic hepatitis C in Saudi patients commonly infected with genotype 4.

AIM: Comparing the efficacy of peginterferon alpha-2b plus ribavirin with interferon alpha -2b plus ribavirin in Saudi patients with chronic hepatitis C virus (HCV) commonly infected with genotype 4. METHODS: A total of 96 patients with chronic HCV infection were randomly assigned to two treatment groups. Forty-eight patients received once weekly 100 microg of peginterferon alpha-2b plus ribavirin given orally 800 mg/day (peginterferon group). Another 48 patients received thrice weekly 3 million units of interferon alpha-2b plus ribavirin 800 mg/day (interferon group). At the end of treatment (48 weeks) and sustained (72 weeks) biochemical and virologic responses were determined. RESULTS: In the peginterferon group, 70.8% (34/48) patients attained both biochemical and virologic responses at the end of the treatment as against 52.1% (25/48) patients in the interferon group. (P=0.09 for both). Similarly, sustained biochemical and virologic responses in the peginterferon group were attained in 52.1% (25/48) and 43.8% (21/48) patients as against 43.8% (21/48) and 29.2% (14/48) patients in the interferon group, respectively (P=0.54 and 0.20, respectively). The sustained virologic response rates in patients with genotype 4 were 42.9% (12/28) in the peginterferon group and 32.3% (10/31) in the interferon group (P=0.43). Patients in peginterferon group had higher, although statistically not significant adverse reactions. CONCLUSIONS: Saudi patients with chronic HCV attained a higher, although statistically not significant sustained virologic response with pegylated interferon plus ribavirin compared with interferon plus ribavirin.

Evidence of DNA repair/processing defects in cultured skin fibroblasts from breast cancer patients.

Cultured skin fibroblasts from 14 breast cancer (BC) patients were compared with those from 8 healthy subjects and 4 ataxia-telangiectasia (A-T) cases for sensitivity to low dose-rate (0.007 Gy/min) gamma-irradiation assessed by a colony-forming assay and for postirradiation DNA synthesis inhibition determined by the method of [(3)H]thymidine incorporation. Fibroblasts from all but two BC patients exhibited moderately enhanced radiosensitivity in the colony-forming assay, occupying an intermediate position between the controls and the A-T cases. Fibroblasts from the radiosensitive BC patients also showed an intermediate response with respect to radio-induced DNA synthesis inhibition compared with those from controls and A-T cases. In a host cell reactivation assay using an irradiated herpes simplex virus for plaque-forming ability, the fibroblasts from 7 BC patients, used as host cells, resulted in a significantly reduced (P < 0.0001) recovery of the virus relative to the 8 control fibroblasts, suggesting a deficiency in DNA repair in the former. A number of the BC fibroblasts analyzed in an assay for potentially lethal damage repair confirmed the repair deficiency in the fibroblasts from the BC patients. Defects in DNA repair and/or DNA processing after exposure to genotoxic agents would lead to genomic instability and hence would be responsible for cancer predisposition. Our data suggest that most BC patients may carry various genes resulting in such defects, and additional studies on normal cells from a larger cohort of BC patients and their family members are warranted to establish a connection between mutations or polymorphisms in specific DNA repair genes and susceptibility to breast cancer.

Effect of deficiency of the double-stranded RNA-dependent protein kinase, PKR, on antiviral resistance in the presence or absence of ribonuclease L: HSV-1 replication is particularly sensitive to deficiency of the major IFN-mediated enzymes.

Control of viral replication by interferon (IFN) is thought to be principally mediated by the 2',5'-oligoadenylate synthetase (OAS)/RNAse L, double-stranded dependent protein kinase (PKR), and myxovirus resistance protein (Mx) pathways. In this study, we monitored the constitutive and IFN-induced antiviral activity in mouse embryo fibroblasts lines derived from mice with targeted disruption of either PKR or PKR/RNAse L genes. At high multiplicity of infection (moi = 10), the absence of PKR had no effect on replication of vesicular stomatitis virus (VSV) but moderately enhanced encephalomyocarditis virus (EMCV) growth and greatly increased replication of herpes simplex virus-1 (HSV-1). Replication of EMCV, HSV-1, and VSV was modestly higher in PKR-/- RNAse L-/- fibroblasts when compared with control cells. Although the antiviral action of IFN-alpha was unaffected by the absence of PKR, IFN action was significantly impaired in the double knockout cells but was dependent on the stage of the virus cycle. At early stages, it appeared that anti-EMCV and anti-HSV-1 action of IFN-alpha was significantly compromised, although weak residual antiviral activity was seen. The action of IFN-alpha against VSV was specifically compromised at a late stage of virus replication. The results showed that PKR is an important mediator in constitutive resistance against HSV-1 and that RNAse L is also necessary for the full antiviral activity of IFN against a variety of viruses. These results supported the existence of novel pathways aimed toward specific stages of the virus life cycle.

Hand contamination with hepatitis C virus in staff looking after hepatitis C-positive hemodialysis patients.

BACKGROUND: Hepatitis C virus (HCV) is a major cause of hepatitis in hemodialysis (HD) patients. Routes other than blood transfusion play a role in the spread of HCV in HD patients. Molecular studies of HCV implicate nosocomial transmission of the virus in HD units. We conducted a clinicovirological study in our HD unit to investigate if the hands of dialysis personnel could represent a mode of transmission of HCV among HD patients. METHODS: One liter of sterile water was used for each handwashing of dialysis personnel. The washing was collected in a sterile container and tested for HCV-RNA by polymerase chain reaction (PCR) within 3 h of collection. Eighty handwashings from nurses dialyzing HCV-positive patients (groupe A) and 100 handwashing from nurses dialyzing HCV-negative patients (group B) were tested for HCV-RNA. As a control, 60 handwashings were collected from the dialysis personnel before entering the dialysis unit (group C) and tested for HCV-RNA. RESULTS: HCV-RNA was positive in 19 (23.75%) of samples of group A, in 8 (8%) of samples of group B (p < 0.003) and in 2 (3.3%) of samples of group C (p < 0. 35). These two positive samples of group C were from nurses who had dialyzed HCV-negative patients. CONCLUSION: These results indicate the presence of HCV-RNA on the hands of some dialysis personnel in our HD unit, in spite fo adherence to the standard precautions. The hands of dialysis personnel are therefore a potential mode for facilitating transmission of HCV between HD patients.

GB virus C/hepatitis G virus infection in Saudi Arabian blood donors and patients with cryptogenic hepatitis.

Viral hepatitis is a common infection in the developing countries. Aside from Hepatitis A-E viruses, a novel hepatitis virus termed GBV-C, or HGV, was recently described. We have studied the prevalence of this virus among Saudi Arabian healthy blood donors (n = 200) and patients with cryptogenic (non-A-E) hepatitis (n=71). After serum extraction and RNA reverse transcription, amplification was carried out by the polymerase chain reaction (PCR), using primers for the 5' noncoding region (NCR), NS5A region and NS3 helicase region. Among the patients with cryptogenic hepatitis, PCR-positivity was 18/71 (25.4%) for the 5' NCR, 14/71 (19.7%) for the NS5A region, and 15/71 (21.1%) for the NS3 helicase region. Among the healthy blood donors, PCR-positivity was 4/200 (2%) for the 5' NCR, 0/200 (0%) for the NS5A region, and 1/200 (0.5%) for the NS3 helicase region. Since the 5' NCR is considered the most conserved segment of the virus genome, it is not unusual to find higher positivity rate when that region is used for amplification. It is noted that the positivity rate is not far different among the three amplified regions, indicating that the heterogeneity of GBV-C/HGV is not as extensive as in hepatitis C virus. Phylogenetic analysis of 5'NCR DNA sequences showed that all isolates in this study belong to genotype 2. We conclude that the prevalence of GBV-C/HGV is similar to what is reported worldwide among the general Saudi population but relatively higher among Saudi patients with cryptogenic hepatitis.

Plasmid profile and antibiotic resistance in coagulase-negative staphylococci isolated from polluted water.

Four different species of coagulase-negative staphylococci (CNS) were isolated from polluted waters in Fez, Morocco and found to be Staphylococcus simulans, Staph. lenticus, Staph. hyicus and Staph. xylosus. Eight isolates belonging to these four species were analysed for their plasmid content. Southern blot hybridizations were performed to define the resistance determinants of the plasmids harboured by these species. These determinants were found to be carried mainly by Class I staphylococcal plasmids (1-5 kb). A plasmid (4.3 kb) carrying a tetracycline resistance gene was present in five isolates from all identified species. Plasmids carrying a chloramphenicol resistance gene were more frequently encountered and found to be of different sizes. Plasmids carrying erythromycin, neomycin, and streptomycin resistance genes were less frequent and were the same size. The results indicate that the occurrence of multi-resistant CNS in polluted waters may constitute a reservoir for disseminating antibiotic-resistance into the community.

The alpha chemokine, interleukin 8, inhibits the antiviral action of interferon alpha.

Interferon (IFN) exhibits a potent antiviral activity in vitro and plays a major role in the early defense against viruses. Like IFN, the proinflammatory chemokine, interleukin (IL)-8, is induced by viruses and appears in circulation during viral infections. In an in vitro cytopathic effect assay for IFN, we found that IL-8 can inhibit IFN-alpha activity in a dose-dependent manner. This action was reversed by specific monoclonal antibodies to IL-8. The chemokine was able to attenuate the IFN-mediated inhibition of viral replication as determined by measuring infectious virus yield. IL-8 also diminished the ability of IFN to inhibit an early stage of viral replication since IL-8 attenuated the inhibition of the formation of viral proteins. It appeared that IL-8 interfered with a late rather than an early step of IFN-mediated pathway such as early gene expression. The IL-8 inhibitory action on IFN-alpha antiviral activity was associated with reduced 2',5'-A oligoadenylate synthetase activity, a pathway well correlative with the anti- encephalomyocarditis virus action of IFN-alpha. Understanding pathways that antagonize IFN action may lead to novel approaches to potentiate endogenous and therapeutic IFN.

Typing of urinary JC virus DNA offers a novel means of tracing human migrations.

Although polyomavirus JC (JCV) is the proven pathogen of progressive multifocal leukoencephalopathy, the fatal demyelinating disease, this virus is ubiquitous as a usually harmless symbiote among human beings. JCV propagates in the adult kidney and excretes its progeny in urine, from which JCV DNA can readily be recovered. The main mode of transmission of JCV is from parents to children through long cohabitation. In this study, we collected a substantial number of urine samples from native inhabitants of 34 countries in Europe, Africa, and Asia. A 610-bp segment of JCV DNA was amplified from each urine sample, and its DNA sequence was determined. A worldwide phylogenetic tree subsequently constructed revealed the presence of nine subtypes including minor ones. Five subtypes (EU, Af2, B1, SC, and CY) occupied rather large territories that overlapped with each other at their boundaries. The entire Europe, northern Africa, and western Asia were the domain of EU, whereas the domain of Af2 included nearly all of Africa and southwestern Asia all the way to the northeastern edge of India. Partially overlapping domains in Asia were occupied by subtypes B1, SC, and CY. Of particular interest was the recovery of JCV subtypes in a pocket or pockets that were separated by great geographic distances from the main domains of those subtypes. Certain of these pockets can readily be explained by recent migrations of human populations carrying these subtypes. Overall, it appears that JCV genotyping promises to reveal previously unknown human migration routes: ancient as well as recent.

Interleukin-8 selectively enhances cytopathic effect (CPE) induced by positive-strand RNA viruses in the human WISH cell line.

Interleukin-8 (IL-8), a proinflammatory chemokine, is induced by viruses and appears in circulation during viral infections. We found that IL-8 enhanced cytopathic effect induced by the positive strand RNA virus, encephalomyocarditis virus (EMCV), in the human WISH cell line. The enhancement was dependent on IL-8 dose and virus dose and was reversible by specific monoclonal antibodies to IL-8. The chemokine was also able to increase EMC viral RNA synthesis and infectious virus yield. This IL-8 enhancing action was not observed in the case of the negative strand RNA virus, vesicular stomatitis virus (VSV), in WISH cells. We examined the activity of constitutive 2',5'-oligoadenylate synthetase (OAS), a pathway that was implicated in protection from EMCV but not VSV. The IL-8 action in EMCV-infected cells, unlike VSV-infected cells, was associated with decreased OAS activity in a manner that was independent of OAS gene expression. Understanding mechanisms of cytokine enhancement of viral activity may lead to novel ways to control viral infections.

Three different GB virus C/hepatitis G virus genotypes. Phylogenetic analysis and a genotyping assay based on restriction fragment length polymorphism.

The 5'-untranslated region (5'-UTR) sequences of 33 GB virus C/hepatitis G virus (GBV-C/HGV) obtained from different geographic areas were determined through reverse-transcription polymerase chain reaction and dideoxy chain termination sequencing, the alignment of sequences, the estimation of the number of nucleotide substitution per site, and construction of phylogenetic trees. The 5'-UTR of GBV-HGV was found to be heterogeneous, with 70.9-99.5% homology. Three distinct phylogenetic branches were observed consistently in all phylogenetic trees. GBV-C is the prototype for one, HGV for another, and there is a new branch which consisted of GBV-C/HGV isolates from Asia. Genotype-specific restriction sites for the restriction enzymes, ScrFI and BsmFI, were identified, and a simple restriction fragment polymorphism analysis was developed for genotyping. These data provide evidence that GBV-C/HGV consists of three different genotypes. Our simple genotyping assay will also provide a tool for epidemiological studies of GBV-C/HGV infection.