Quasispecies of genotype 4 of hepatitis C virus genomes in Saudi patients managed with interferon alfa and ribavirin therapy

Many patients with hepatitis C virus [HCV] infection do not respond to antiviral treatment, possibly due to viral quasispecies. We aimed to investigate whether the quasispeices population could be used as a predictor of response to therapy in our patients. The quasispecies of HCV genotype 4 [HCV-4] were studied in 25 naive Saudi patients at zero, three, and six months following interferon alfa and ribavirin combination therapy. Hypervariable region 1 within the E2/NS1 gene of the virus was analyzed by the single-strand conformation polymorphism [SSCP] technique after amplification. Pretreatment DNA bands by SSCP [2-7 bands] were detected in all patients. In those who achieved a complete virological response within six months [viral load <0.2 Meq/mL; n=7], bands ranged from 2-6 [mean = 3.71 +/- 1.25]. In six of these seven patients, the number of SSCP bands remained either the same or decreased sequentially. In those patients who did not respond [viral load >0.2 Meq/mL; n=18], the bands also ranged from 2-7; mean 3.77 +/- 1.73. In six of these non-responding patients, the SSCP bands remained the same or decreased sequentially. There was no significant difference between pretreatment quasispecies composition and response [P=.53]. Two of the four patients with pretreatment high viral load and the same or decreased composition of quasispecies bands responded to the therapy. Quasispecies in our studied patients cannot be used to predict responsiveness to treatment, but may offer an explanation for failure of most HCV-4 patients to respond to interferon alfa and ribavirin therapy

Inhibition of growth of Leishmania donovani promastigotes by newly synthesized 1,3,4-thiadiazole analogs

Leishmania donovani, the causative agent of visceral leishmaniasis, is transmitted by sand flies and replicates intracellularly in their mammalian host cells. The emergence of drug-resistant strains has hampered efforts to control the spread of the disease worldwide. Forty-four 1, 3, 4-thiadiazole derivatives and related compounds were tested in vitro for possible anti-leishmanial activity against the promastigotes of L. donovani. Micromolar concentrations of these agents were used to study the inhibition of multiplication of L. donovani promastigotes. Seven compounds were identified with potential antigrowth agents of the parasite. Compound 4a was the most active at 50 micro M followed by compound 3a. These compounds could prove useful as a future alternative for the control of visceral leishmaniasis

Human papilloma virus-16/18 cervical infection among women attending a family medical clinic in Riyadh

Prevalence information is lacking on human papillomavirus types 16 and 18 [HPV-16/18] infection in cervical tissues of women residing in Riyadh, Saudi Arabia. In addition, there are no observations on progression to cervical intraepithelial neoplasia [CIN]. Pap smear and HPV-16/18 DNA detection by PCR followed by Southern blotting was performed on 120 subjects [Saudi and other Arab nationals] during routine gynecological examination. Some HPV-positive subjects were followed for 4 years, by Pap smear every 6 months and by HPV DNA detection at the end of 4 years. Overall HPV-16/18 prevalence was 31.6%. HPV-16 prevalence alone was 13.3%, HPV-16 as a mixed infection with HPV-18 was 15%, and all HPV-16 was 28.3%. HPV-18 alone was 3.3%, HPV-18 as a mixed infection with HPV-16 was 15%, and all HPV-18 was 18.3%. Ten subjects had cervical abnormalities with the Pap smear test, six of whom were HPV-16/18 positive, 1 with HPV-16, 1 with HPV-18, and 4 with a mixed infection of HPV-16/18. Of all 23 HPV-16/18-positive subjects, either as individual or mixed infection, followed for 4 years, 7 showed abnormal cytology 6 at initial examination and 1 during follow-up. Of these 7, 6 reverted to normal without treatment and 1 was treated and became normal after 3 years. None of the subjects progressed to CIN-III. A high prevalence of HPV-16/18 was found, but with a low rate of progression to CIN. A significant association with abnormal cytology was found only in patients with HPV-16/18 mixed infection

Molecular epidemiology and genotyping of TT virus isolated from Saudi blood donors and hepatitis patients

In Saudi Arabia, the epidemiology and clinical significnance of Torque Teno virus [TTV] infection alone and in patients with hepatitis virus infections have not been determined in a single study. In this paper, we molecularly investigated the rate and genotypes of TTV infection among Saudi Arabian blood donors and patients with viral hepatitis. The effect of TTV coinfection on viral hepatitis was also examined. DNA was extracted from the sera of 200 healthy blood volunteers, 45 hepatitis B virus patients, 100 hepatitis C virus patients, 19 hepatitis G virus patients, and 56 non-A-G hepatitis patients. TTV DNA was amplified using primers derived from the ORF1 and 5'UTR regions. The alanine aminotransferase [ALT] level was determined for each specimen. Sequencing of ORF1 amplicons was carried out to investigate TTV genotypes. Using primers derived from ORF1 and 5'UTR, TTV DNA was detected in 5.5% and 50.5%, respectively, of healthy blood donors, in 2.2% and 88.8% in hepatitis B patients, in 2.0% and 70% of hepatitis C patients, in 15.8% and 100% of hepatitis G patients, in 5.4% and 12.5% of non-A-G hepatitis patients and in 4.8% and 56.4% overall. No detrimental effect of TTV coinfection in viral hepatitis patients was noted. An overall prevalence of 4.8% and 56.4% was established. Phylogenetic analysis indicated that the most common genotype of TTV among Saudis is 2c. The rate of TTV infection among Saudi Arabians seems to be lower than that stated in previous reports on Saudi Arabia and in some other countries. The virus does not seem to worsen the status of those who are suffering from viral hepatitis infection

comparative study on the application of 3 molecular methods in epidemiological typing of bacterial isolates using MRSA as a prototype

To evaluate and compare 3 widely used molecular techniques, namely, restriction endonuclease analysis of plasmid deoxyribonucleic acid [REAP], randomly amplified polymorphic DNA [RAPD] and pulsed-field gel electrophoresis [PFGE] for their suitability and usefulness in the typing and fingerprinting of bacterial isolates. Twenty-four epidemiologically unrelated methicillin-resistant Staphylococcus aureus [MRSA] isolates were used to evaluate the molecular typing methods [REAP, RAPD and PFGE]. The study was conducted at the Research and Diagnostic Laboratories of King Faisal Specialist Hospital and Research Center from January 2002 through January 2003. Only 20.8% of all isolates studied were of the same genotypes by all 3 methods. Two major clusters of strains each representing 33% of the total number of isolates were identified by REAP analysis. Each of RAPD and PFGE however, identified one major cluster represented by 54% and 83% of the total number of isolates, All 3 typing methods, therefore, showed the clonal genetic relatedness among distant MRSA isolates. However inter-strain comparison of fingerprint data generated from each method revealed differences in clonal representation of the MRSA isolates. Although a variety of molecular assays are available for typing of bacterial species, there is no single standardized protocol for routine analysis. Reproducibility and interpretation of genotypic data are therefore, highly dependent on methodologies employed by the individual laboratory. Our findings illustrate the importance of using a combination of methods in typing schemes of bacterial isolates. In terms of reproducibility and typeability we found that PFGE is superior to REAP and RAPD and, therefore, more suitable for routine, standardized tracing of nosocomial bacterial isolates

Genotyping of hepatitis C virus isolates from Saudi patients by analysis of sequences from pcr-amplified core region of the virus genome

We investigated the genotype distribution of hepatitis C virus [HCV] among Saudi patients with chronic hepatitis C. Serum specimens from 119 native Saudi Arabian patients with chronic hepatitis C, as documented by serology and polymerase chain reaction [PCR] for HCV RNA, were used. Genotyping was performed by reverse transcription-PCR, using specific primers at the core region of HCV genome, and DNA sequencing of the resultant amplicons. It was found that the majority of samples [47.9%] belong to genotype 4, followed by subtype Ib [16.8%], and subtype la [10.1%]. Twenty samples [16.8%] were not able to be typed by our method. We confirmed the results by cloning at least one PCR amplicon from each genotype, and determining the nucleotide sequence of the clones. Our findings suggest that genotype 4 is the most common among native Saudi Arabian patients with chronic hepatitis C infection. Genotypes Ib and la were also prevalent

Incidence of rotaviral gastroenteritis at a referral centre in Saudi Arabia

The incidence of gastroenteritis caused by rotavirus was investigated at a referral hospital in Saudi Arabia over a period of 4.5 years. Of the 1,729 patients with suspected infection, 547 [31.6%] were positive for rotavirus infection. Most were inpatients [65] and 75.7% of the patients were under 12 years of age. Of the 414 positive patients under 12 years of age, 63% were inpatients. Similarly, 74.4% of the 25-year and older group were inpatients. However, 40.3% of them were abnormal hosts because they either harbored neoplasms or had undergone bone marrow transplantation