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Background: Malaria was eradicated in Bahrain about 20 years ago. However, because of a large immigrant population, cases of imported malaria continued to be seen. This paper presents an evaluation of the data from 1992 to 2001 to assess the levels of indigenous and imported malaria cases and the potential for reemergence of malaria transmission in the country.Methods: Epidemiologic and parasitologic data on confirmed malaria cases during the review period were analyzed. Data on vector breeding activity were also analyzed to determine the potential for reemergence of local transmission.Results: From 1992 to 2001, 1,572 cases of malaria were reported. All were imported malaria cases. There was a consistent decline in the number of cases, from 282 (the peak level) in 1992 to 54 in 2001. Eighty-four percent (1,318/1,572) of infections were contracted as a result of travel to or previous domicile in five countries, namely India, Pakistan, Sri Lanka, Bangladesh and Sudan. Plasmodium vivax was the etiologic agent in 85.6% (1,346/1,572) of cases, with Plasmodium falciparum accounting for 14% (220/1,572). During this period, the percentage of examined breeding sites where Anopheles mosquito larvae were identified remained fairly constant, ranging between 0.05% and 0.1%.Conclusions: From 1992 to 2001, there was a consistent decline in the number of imported malaria cases in Bahrain. There were no cases of locally acquired malaria during this period. The low level of vector breeding spots with Anopheles mosquito larvae suggests that the potential for reemergence of local transmission remains low. [ABSTRACT FROM AUTHOR]

Primary Human Herpesvirus-6 (HHV-6) infection has been related to different clinical pictures and, notably, to Chronic Fatigue Syndrome (CFS). We studied 52 patients fulfilling the criteria of Centers for Disease Control (CDC) for CFS and a control group of 51 matched healthy blood donors. HHV-6 was recovered by culture and confirmed by immunofluorescence assay (IFA) and by PCR in 30/52 patients (57.7%) and in 6/51 (11.7%) of blood donors. [ABSTRACT FROM AUTHOR]

The physical properties of polymers can be significantly altered by blending them with inorganic components. This can be done during the polymerization process, but also by post-processing of already shaped materials, for example through coating by atomic layer deposition (ALD) or hybridizing through vapor phase infiltration (VPI), both of which are beneficial in their own way. Here, a new processing strategy is presented, which allows distinct control of the coating and infiltration. The process is a hybrid VPI and ALD process, allowing separate control of infiltrated and coated components. This new simultaneous vapor phase coating and infiltration process (SCIP) enhances the degrees of freedom for optimizing the properties of polymers, as shown on the example of Kevlar 29 fibers. The SCIP treated fibers show an increase of 17% of their modulus of toughness (MOT) in comparison to native Kevlar, through the nanoscale coating with alumina. At the same time their intrinsic sensitivity to 24 hours UV-irradiation was completely suppressed through another infiltrated material, zinc oxide, which absorbs the UV irradiation in the subsurface area of the fibers., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Objectives: To determine the trafficking of methicillin-resistant staphylococci between the hospital and community as well as the occurrence of co-colonization with vancomycin-resistant enterococci (VRE)., Subjects and Methods: From November 2005 to April 2006, methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus (MRCoNS)-positive patients at the Salmaniya Medical Complex, Bahrain were assessed for VRE co-colonization. Characterization of vancomycin resistance genotype by PCR was carried out. Close family contacts were screened for MRSA and pulsed-field gel electrophoresis (PFGE) analysis of MRSA isolates from patient-family member pairs was conducted., Results: One hundred and eighty-two patients (93 MRSA; 89 MRCoNS) and 356 family members were enrolled. Seven MRSA and 41 MRCoNS strains were isolated from the family members. PFGE analysis revealed the presence of variants of a single MRSA clone among patients and their relatives. A total of 112 patients (62 MRSA; 50 MRCoNS) provided stool for VRE screening. Of these 13 stool specimens (11.6%) were VRE-positive. All the VRE isolates were from MRSA-positive patients, thus positivity rate among MRSA patients was 20.9% (n/N = 13/62). These were predominantly Enterococcus gallinarum with vanC1 genotype and one strain was Enterococcus faecium (vanB genotype). Two E. gallinarum isolates harbored an additional vanB gene. The majority of VRE isolates were from patients in medical and surgical units (n/N = 10/13; 77%). Male gender, prolonged hospitalization and presence of co-morbidities were significantly associated with MRSA/VRE co-colonization (p < 0.05)., Conclusion: MRSA/VRE co-colonization with MRSA trafficking between the hospital and community environment is a public health concern occurring in our setting., (Copyright © 2011 S. Karger AG, Basel.)

Objective: To determine the molecular characterization of extended-spectrum beta-lactamases (ESBL) isolates from a tertiary center in Saudi Arabia using multiplex polymerase chain reaction (PCR) technique and assess their antibiotic susceptibility pattern., Methods: Prospective study conducted at the Saudi Aramco Dhahran Health Center, Dhahran, Saudi Arabia between April-December 2006. Extended-spectrum beta-lactamases phenotype of isolates identified by automated methods was confirmed using E-test. Multiplex PCR for the detection of blaTEM, blaSHV and blaCTX-M was performed. Susceptibility to a panel of antibiotics was determined., Results: One hundred isolates (Escherichia coli [E.coli] n=84; Klebsiella pneumoniae [K. pneumoniae] n=16) were studied and 71% harbored the blaCTX-M gene. For E.coli isolates 43 (51%) harbored CTX-M+TEM combination and 21 (25%) had CTX-M alone. In contrast, only one K. pneumoniae isolate (6.2%) harbored the CTX-M+TEM combination and 3 (18.8%) isolates had CTX-M only. One E.coli and 7 K. pneumoniae isolates were blaSHV positive. The blaCTX-M gene was found predominantly in urinary isolates (n=63/71; 88.7%). The presence of blaCTX-M was significantly higher in isolates from outpatients compared to inpatient (p<0.05). Sensitivity to imipenem was 100% and 78% to nitrofurantoin. Resistance to amoxicillin-sulbactam was significantly higher in blaCTX-M positive isolates (p<0.05)., Conclusion: The findings indicate a high-level of blaCTX-M positive ESBL isolates circulating in our setting with the dissemination of these in the community. The trend of multidrug resistance profile associated with carriage of blaCTX-M gene is cause for concern.

Background: The dominance of lactobacilli in healthy vaginal microbiota and its depletion in bacterial vaginosis (BV) has given rise to the concept of oral or vaginal instillation of probiotic Lactobacillus strains for the management of this condition., Objectives: To ascertain the efficacy of probiotics in the treatment of BV., Search Strategy: We searched electronic databases irrespective of publication status or language. These included: Cochrane Central Register of Controlled Trials (CENTRAL), the HIV/AIDS and STD Cochrane Review Groups' specialized registers, the Cochrane Complementary Medicine Field's Register of Controlled Trials, MEDLINE (1966 to 2008), EMBASE (1980 to 2007), ISI science citation index (1955 to 2007), CINAHL (Cumulative Index to Nursing & Allied Health Literature (1982 to 2007).We handsearched of specialty journals, conference proceedings and publications list on the website of the International Scientific Association of Probiotics and Prebiotics (http://www.isapp.net/default.asp).For unpublished studies or ongoing trials, we contacted authors from relevant publications, nutraceutical companies and probiotic-related scientific associations. We searched electronic databases on ongoing clinical trials., Selection Criteria: Randomized controlled trials using probiotics for the treatment of women of any age diagnosed with bacterial vaginosis, regardless of diagnostic method used. The probiotic preparation could be single or "cocktail" of strains, any preparation type/dosage/route of administration. Studies comparing probiotics with placebo, probiotics used in conjunction with conventional antibiotics compared with placebo or probiotics alone compared with conventional antibiotics were eligible for inclusion., Data Collection and Analysis: We screened titles and abstracts , obtained full reports of relevant trialsand independently appraised them for eligibility. A data extraction form was used to extract data from the four included studies. For dichotomous outcomes, odds ratios (OR) and 95% confidence intervals (CI) were derived for each study using RevMan (versions 4.2 and 5). We did not perform meta-analysis due to significant differences in the probiotic preparations and trial methodologies., Main Results: Analysis suggests beneficial outcome of microbiological cure with the oral metronidazole/probiotic regimen (OR 0.09 (95% CI 0.03 to 0.26)) and the probiotic/estriol preparation (OR 0.02, (95% CI 0.00 to 0.47)). For the probiotic/estriol preparation, the OR and 95% CI for physician-reported resolution of symptoms was OR 0.04 (95% CI 0.00 to 0.56)., Authors' Conclusions: The results do not provide sufficient evidence for or against recommending probiotics for the treatment of BV. The metronidazole/probiotic regimen and probiotic/estriol perparation appear promising but well-designed randomized controlled trials with standardized methodologies and larger patient size are needed.

Background: To assess the prevalence of extended spectrum beta-lactamase (ESBL) producing Escherichia coli and Klebsiella strains in nosocomial and community-acquired infections., Methodology: The study was conducted at a centralized microbiology laboratory in the Eastern Province of Saudi Arabia. Laboratory records (January 2004 - December 2005) were assessed. Associated resistance to a panel of antibiotics was determined., Results: A total of 6,750 Gram-negative organisms were assessed for ESBL-phenotype. ESBL was detected in 6% (409/6,750) of isolates, the majority of which were E. coli (83%). ESBL producers were significantly higher among isolates from in-patients 15.4% (143/927) versus out-patients (4.5%; 266/5,823); p < 0.05. Old age (older than 60 years) represented a significant risk for having an ESBL-producing pathogen. Urine was the major source of ESBL isolates in in-patients (46.1%) and out-patients (74.4%). The proportion of urinary E. coli isolates which were ESBL producers was significantly higher among in-patients (53/506; 10.4%) compared to out-patients (182/4,074; 4.4%); p<0.05. Old age (older than 60 years) represented a significant risk for having an ESBL-producing pathogen. Urine was the major source of ESBL isolates in in-patients (46.1%) and out-patients (74.4%). The proportion of urinary E. coli isolates which were ESBL producers was significantly higher among in-patients (53/506; 10.4%) compared to out-patients (182/4,074; 4.4%); p<0.05. Among in-patients, 60% of the ESBL associated infections were nosocomial. All were sensitive to imipenem but high levels of resistance to gentamicin, amikacin, amoxicillin-clavulanic acid and ciprofloxacin was shown., Conclusion: The findings document evidence of the spread of multiresistant ESBL-producers into the community. This has significant implications for patient management, and indicates the need for increased surveillance and molecular characterization of these isolates.

Diarrhoea illnesses constitute a common cause of morbidity and mortality worldwide. In recent years, Campylobacter spp. has been recognized as the leading cause of bacterial enteritis in both developed and developing countries. The biology of Campylobacters as well as the mechanism by which they cause disease is yet to be fully explained. In addition, non-availability of fast and reliable diagnostic methodology and the growing trend of antibiotic resistance continue to pose significant challenges. The absence of national surveillance programs for campylobacteriosis, particularly in developing countries, makes it difficult to give an accurate picture of the true infection prevalence and the molecular epidemiology of isolates circulating in the populations, a situation which had hitherto existed in the Arabian Gulf region. However, in recent years, emerging data from studies in the Arabian Gulf region has not only enhanced our understanding of the epidemiology of Campylobacter both in humans and poultry in the region, but has also contributed to the overall understanding of the mechanism of Campylobacter enteritis, antibiotic resistance, and improved diagnostic approaches. In this review, we examine these emerging data from the Arabian Gulf region.

Objective: To examine the kinetic ability of embryonic human epithelial INT-407 cells to express messenger ribonucleic acid mRNA for various cytokines and chemokines in response to Campylobacter jejuni C. jejuni stimulation., Methods: In an experimental single-blind study, cultured embryonic human epithelial INT-407 cells were treated with different concentrations of viable C. jejuni, its sonicated, and filtered supernatant. A modified non-radioactive in situ hybridization using probe cocktails was used to measure mRNA levels for the pro-inflammatory cytokines interleukin IL-1beta, IL-6, interferon-gamma IFN-gamma, tumour necrosis factor TNF-alpha, transforming growth factor TGF-beta1, and IL-8, and the anti-inflammatory cytokines, IL-4 and IL-10. The study was carried out from September 2005 to March 2007 at the Department of Microbiology, Immunology, and Infectious Diseases, College of Medicine, Arabian Gulf University, Bahrain., Results: Viable C. jejuni, sonicated bacteria and filtered supernatant induced high mRNA expression for the pro-inflammatory cytokines IL-1beta, IL-6, IFN-gamma, TNF-alpha, TGF-beta1, and IL-8, which peaked at the 12 hours post stimulation. Anti-inflammatory cytokines IL-4 and IL-10 mRNA expression were induced maximally at 3 hours post stimulation mainly by sonicated bacteria and filtrated supernatant, however, not with living bacteria. Untreated embryonic human epithelial INT-407 cells expressed low amount of mRNA for the various cytokines and chemokines at all time points. For each cytokine, 4 samples were used per time hour., Conclusion: This study demonstrated that embryonic human epithelial INT-407 cells in response to viable C. jejuni or its cytotoxins can alter cytokine and chemokine mRNA expression patterns and kinetics suggesting a potential role for theses mediators in the immunopathogenesis of the infection caused by this pathogen, which might be relevant for future immunotherapeutic interventions during severe bacterial infections.

Differentiation between Campylobacter jejuni and Campylobacter coli is problematic in clinical specimens due to fastidious growth requirements and limited biochemical tests. This study describes a rapid, multiplex PCR protocol for the direct detection and differentiation of C. jejuni and C. coli in stools. An evaluation was carried out of this multiplex protocol based on the detection of cadF (genus specific), and hipO (C. jejuni) and asp (C. coli) genes, using stool from patients with Campylobacter enteritis and chicken. Protocol sensitivity was assessed and specificity determined using a panel of enteric bacteria, and evaluation of 30 diarrhoeic stool specimens culture negative for Campylobacter. Of the 114 specimens (54 human and 60 chicken) evaluated by the protocol, 70 (61.4 %) were identified as C. jejuni, 35 (30.7 %) as C. coli and 9 (7.9 %) as a mixed infection/colonization with both species. All mixed infections were identified as C. jejuni by culture. Among the stool specimens that were culture negative for Campylobacter, two (6.7 %) were C. jejuni positive by multiplex PCR. The protocol sensitivity limit was 0.015-0.016 ng C. jejuni and C. coli DNA mul(-1) in the specimen. There was no cross-reaction with the reference strains assessed. Comparison of hippurate test and multiplex PCR demonstrated 17 isolates with false-positive hippurate enzymic activity and 7 with false-negative activity. This rapid protocol (turnaround time 6 h) is highly sensitive and specific for direct evaluation of stool for these pathogens. It has significant application for routine clinical diagnostic and epidemiological purposes.

This nationwide study was conducted to assess the extent of adherence of primary-care physicians to the World Health Organization (WHO)-recommended guidelines on the use of oral rehydration therapy (ORT), antimicrobials, and prescribing of other drugs used in treating symptoms of acute diarrhoea in Bahrain. A questionnaire-based, cross-sectional survey was carried out in primary-care health centres. During a six-week survey period (15 August-30 September 2003), 328 (25.2%) completed questionnaires were returned from 17 of 20 health centres. In a sample of 300 patients, oral rehydration salts (ORS) solution was prescribed to 89.3% (n=268) patients; 12.3% received ORS alone, whereas 77% received ORS in combination with symptomatic drugs. Antimicrobials were prescribed to 2% of the patients. In 11.4% of the cases, rehydration fluids and other drugs were given parenterally The mean number of drugs was 2.2+0.87 per prescription. In approximately one-third of the patients, three or more drugs were used. Primary-care physicians almost always adhered to the WHO guidelines with respect to ORT and antimicrobials. However, in several instances, ORT was prescribed along with polypharmacy, including irrational use of drugs for symptomatic relief. Effective health policies are needed to reduce the unnecessary burden on the healthcare system.

The association between putative virulence genes in Campylobacter jejuni clinical isolates, in vitro invasive capability and severity of infection is yet to be clearly described. We have characterized three virulence genes and correlated their presence with the severity of infection and in vitro invasiveness. We studied eight C. jejuni strains isolated from patients whose clinical data were scored to determine severity of infection. Cytolethal distending toxin (cdtB), invasion associated marker (iam) and Campylobacter invasion antigen (ciaB) genes were detected by PCR and INT407 cells used for invasion assays. Two strains positive for all three genes were the most invasive and isolated from patients with the most severe infection. Four strains positive for two genes and two strains negative for all the three genes were identified. The two cdtB(+ve)/ciaB(+ve) strains were more invasive than the cdtB(+ve)/iam(+ve) strains. One of the cdtB(-ve)/ciaB(-ve) strains showed invasion levels similar to cdtB(+ve)/ciaB(+ve) strains, but the second strain had a non-invasive phenotype. The findings indicate a correlation between in vitro invasive capability, and the presence of all three genes. The pattern of association between invasiveness and molecular characterization suggests that the ciaB gene confers a more invasive capability.

There are no data describing the genetic make-up of Campylobacter strains (an important aetiological agent of diarrhoea) circulating in the Arabian Gulf region. Here, the molecular characterization of two virulence genes in Campylobacter jejuni from Bahrain and the relationship with clinical infection are reported. Molecular screening for cytolethal distending toxin (cdtB) and invasion-associated marker (iam) genes was carried out on C. jejuni stool isolates collected from January 2002 to January 2004 in Bahrain. The molecular characterization was correlated with the patients' socio-demographic and clinical parameters. Of the 96 C. jejuni strains tested, 50 (52 %) were cdtB+/iam+, 30 (31 %) were cdtB+/iam- and 16 (17 %) were cdtB-/iam-. Sixty-nine per cent (66/96) of patients were less than 3 years old, with significantly higher detection of cdtB+/iam+ and cdtB+/iam- strains (P < 0.001 and P < 0.01, respectively) in this age group. Seventy patients (73 %) were symptomatic. In the group that were less than 3 years old, 62 and 85 % of those with cdtB+/iam+ and cdtB+/iam- strains, respectively, were symptomatic compared with 100 % for those over 3 years of age. However, the presence of cdtB-/iam- strains still resulted in clinical infection in the children under 3 years but not in the older patients. This is the first report describing the molecular characterization of virulence genes in Campylobacter isolates from this region. The findings indicate that strains of different virulence genetic make-up are circulating in the population, with children under the age of 3 years being most vulnerable. Further work on the molecular characterization, gene expression and determination of the invasive phenotypes of C. jejuni strains circulating in different regions is needed.

Objective: To investigate the occurrence of human papillomavirus (HPV) infection and the associated risk factors in Bahrain's female population., Methods: This study was carried out between March to December 2004, which includes cervical scrapings for Pap smear and HPV-DNA testing using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis, obtained from 100 women attending the Gynecology Clinic at Salmaniya Medical Center and Sheikh Sabah Health Center in the Kingdom of Bahrain. We distributed questionnaires that include the sociodemographic data as well as information on risk factors such as smoking, parity, and the contraceptive used., Results: Eleven women (11%) with normal cytology were HPV-positive. The RFLP analysis detected HPV-types 16, 18, 45, 62 and 53. Positive women were significantly older (43.3 +/- 10.1 years) than negatives (36.5 +/- 9.9 years; p=0.04), however, there was no difference in age of first sexual contact (positive: 18.1 +/- 5.7 years versus negative: 20.6 +/- 4.4 years). Polygamy, smoking and hormonal contraception was not identified as risk factors, but positive women showed higher parity., Conclusion: In this study on HPV infection in Bahrain, the 11% positivity with high risk HPV types, in the presence of normal cytology suggests that in addition to the cervical cancer screening program, offer of HPV testing deserves consideration.

Objectives: To investigate the organisms causing neonatal sepsis and their modifications over an extended period, to assess their changing sensitivities to antibiotics and to verify whether the policy for screening pregnant women for group B streptococci (GBS) carriage is desirable in our settings., Subjects and Methods: Medical records of all infants with positive blood culture from the Neonatal Intensive Care Unit at Salmaniya Medical Complex between 1991 and 2001 and Bahrain Defense Force Hospital between 1999 and 2001 were reviewed., Results: Of the 7,978 neonates in both hospitals 335 (4.19%) had culture-proven bacteremia. Gram-positive bacteria were isolated at constant rate over the 11-year period. The main agents isolated were coagulase-negative Staphylococcus (CoNS) in 138 cases (41%), Staphylococcus aureus in 28 newborns (8%) and GBS in 26 patients (7.8%, 0.2/1,000 live births). All of them were sensitive to penicillin G, erythromycin and clindamycin. Gram-negative bacteria were declining but Escherichia coli was isolated in 35 cases (10%). Of special concern is the increasing percentage (5.7%) of Candida isolation. No clear trend toward increasing resistance was observed, although a major difference among the two institutions was evident. Klebsiella and Enterobacter spp. showed resistance to many of the antibiotics tested, thereby posing difficult therapeutic choices., Conclusion: Good quality specimens are essential to evaluate the role of CoNS. The increasing threat of fungal infection must be carefully tackled. Specifically tailored policies for GBS prevention must be defined according to the local epidemiology., ((c) 2006 S. Karger AG, Basel)

In recent years there has been a significant upsurge in research on the characterisation and verification of the potential health benefits associated with the use of probiotics. In addition, the market for probiotics continues to expand exponentially as consumers (mostly healthy individuals) rely on health claims made by manufacturers to make their choices. This review appraises the available evidence for and against the health claims associated with probiotics. The use of probiotics in promoting gastrointestinal health and immunity, and their use in the prevention of urogenital infections, allergies and cancer are reviewed. Furthermore, issues surrounding the use of probiotics in healthy individuals, the safety of probiotics and regulatory concerns are addressed. There is scientific evidence that specific strains of probiotic microorganisms confer health benefits on the host and are safe for human use. However, this evidence cannot be extrapolated to other strains, as these effects are strain-specific. Probiotics have potential health benefits for conditions such as gastrointestinal infections, genitourinary infections, allergies and certain bowel disorders, all of which afflict a considerable proportion of the global population. However, considerable work is still needed to confirm these potential health benefits.

Objectives: To investigate the effect of pre-exposure antibiotics on cytolethal distending toxin (CDT) production and toxigenic effect of C. jejuni., Methods: Sonicates and filtrates were prepared from known cdt+ and cdt- isolates of C. jejuni which had been pre-exposed to varying concentrations (MIC, 1/2 MIC, 1/4 MIC, 1/8 MIC) of erythromycin and ciprofloxacin. The CDT toxigenic effect was examined using INT 407 and HeLa cells., Results: A trend of increased toxigenic effect was observed with pre-exposure to antibiotics. This was more pronounced with erythromycin pre-exposure compared to ciprofloxacin. Although a trend of increasing toxigenic effect with decreasing antibiotic concentration was demonstrable, some differences were observed between isolates. In one isolate the increased toxigenic effect was statistically significant (P<0.05) at 1/4 MIC in INT 407 cells and at 1/8 MIC in HeLa cells., Conclusions: This study provides evidence of an association between CDT production by C. jejuni and pre-exposure to antibiotics. Pre-exposure to ciprofloxacin and erythromycin at concentrations below MICs could potentiate CDT activity. Further work is needed to elucidate the mechanism involved. We recommend that these antibiotics be used in the treatment of C. jejuni enteritis only when strongly indicated and with careful monitoring of patients.

Objectives: To investigate the production of dynamic alpha and beta chemokines represented by interleukin-8 (IL-8) as alpha chemokine and CCL2 (monocyte-chemoattractant protein-1, CCR2 ligand), CCL4 (macrophage-inflammatory protein-1beta, CCR5 ligand), CCL3 (macrophage-inflammatory protein-1alpha, CCR1/5 ligand), (CCL5, regulated upon activation, normal T-cell expressed and secreted (RANTES, CCR5 ligand) as beta chemokines by the human intestinal cell line INT407 stimulated with factors produced by living Campylobacter jejuni (C. jejuni) and those present within sonicated and filtrated bacteria., Methods: We used immunohistochemical technique modified to detect intracellular production of cytokines protein and RT-PCR to read RNA messages for evaluation of de novo cytokine synthesis., Results: Living bacteria induced increased numbers of IL-8, CCL4 and CCL2 but not CCL3 or CCL5 producing cells. Low numbers of IL-8, CCL4 and CCL2 producing cells were detected with filtrated supernatant compared to living and sonicated bacteria. A non-significant low number of chemokine producing cells was noted when comparing numbers of chemokine producing cells stimulated with living C. jejuni to those stimulated with sonicated bacteria, indicating that the triggering factors involved in stimulation with living bacteria were still active after sonication, but they were largely lost upon filtration. The mRNA signals for IL-8 were noted in conformity with its protein levels as increased IL-8 mRNA signals were registered after stimulation with living and sonicated bacteria but not with filtrated supernatant., Conclusions: Preferential production of chemokines probably induced by membrane associate factors of C. jejuni acting on intestinal epithelial cells is presented. These chemokines are suggested to be part of an inflammatory network affecting cell types that contribute to initiation and/or resolution of the infection.

Objectives: To study the action of factors produced by living Campylobacter jejuni (C. jejuni) against those present within sonicated and filtrated bacteria on induction of potential cytokines by the human intestinal cell line INT407., Methods: We used immunohistochemical technique modified to detect intracellular production of cytokines protein and RT-PCR to read RNA messages for evaluation of de novo cytokine synthesis., Results: The data herein display dissociation of cytokine profiles induced on by living C. jejuni. Exposure of INT407 cells to 10(6) live bacteria showed the highest numbers of cytokine producing cells of all examined cytokines. IFN-gamma was the highest induced cytokine followed by IL-10, TNF-alpha and lastly IL-4. Also, abrogation of induction of the proinflammatory cytokines IFN-gamma and TNF-alpha but not the antiinflammatory cytokines IL-4 and IL-10 by sonicated and filtrated bacteria was depicted. At the mRNA level, TNF-alpha signals were noted in accordance with its protein levels since increased TNF-alpha mRNA signals were registered only after stimulation with living bacteria. Very low or no induction of TNF-alpha was registered with non-stimulated cells., Conclusions: These results illustrate for the first time a role for factors from living bacteria in directing the immune response towards Th1 type. Characterization of such factors may be essential for future immunotherapeutic interventions during severe bacterial infections.

Objectives: To assess the impact of the introduction of a new quality control/quality assurance (QA/QC) protocol on the processing and reporting of respiratory specimens., Methods: After implementation of guidelines for processing respiratory specimens, an investigation was carried out over a six-month period on 200 specimens, 105 sputa, and 95 deep tracheal aspirates (DTAs), assessed blindly by two independent investigators. Data regarding disagreement were arranged into two subgroups. A minor disagreement was defined as a difference in the two assessments of < 10 or 10-25 for white blood cell (WBC) or squamous epithelial cell (SEC) counts. A major disagreement was defined as one assessor reporting < 10 and the other > 25 for either WBC count or SEC count, or one assessor reporting the specimen as non-assessable, or both assessors having a minor disagreement in both the WBC count and the SEC count., Results: Agreement was obtained on 111 samples. For 45 specimens, a major disagreement was documented, and in 44 cases, a minor disagreement was recorded, WBC being the most common cause of divergence. Data for sputa and DTAs were examined separately: of 45 major disagreements, 64.4% were observed for DTAs, while minor disagreements were recorded mostly for sputa. The role of the settings in which samples were taken in affecting quality was studied. Among the 105 sputa, 27 were from Community Health Centers (CHCs) and 78 from hospitalized patients. Agreement between the two observers was obtained in 48.1% of CHC cases versus 60.2% of hospital samples. To investigate how many of the rejected samples presented WBC > 25 suggestive of infection, we looked at the 107 samples rejected during the six-month period, grouped according to the suspected diagnosis. The highest number of rejected samples falls in the category of unrelated (non-respiratory) diagnosis, and clinical suspicion is not helpful in Gram stain interpretation. The annual saving (not culturing, not testing, and not treating) derived from this simple QC procedure totals about 5000 Euro., Conclusions: Standardization in microscopic screening of respiratory samples is difficult to achieve. Criteria for rejection must be adapted to local conditions after discussion with clinicians to increase their compliance with the newly introduced guidelines and to avoid sending unnecessary specimens. The effects on patient management and cost control are significant.

Objectives: To investigate the enteropathogens in children with diarrhea attending Salmaniya Medical Complex, Bahrain., Methods: Fecal samples from 805 children up to 15 years were examined for parasites, ova and cysts by direct wet preparation, formol-ether concentration and modified Ziehl-Neelsen stain, during the period November 1998 through to June 2000. Samples were cultured for Salmonella, Shigella, Campylobacter and Enteropathogenic Escherichia coli. Antibiotic sensitivity tests were performed on the relevant clinical isolates by agar disk diffusion method. All stools from children below 3 years of age (653 samples) were processed for adenovirus and rotavirus using a commercially available latex agglutination test (Diarlex). In addition, reverse transcription-polymerase chain reaction was performed on 200 randomly selected samples using oligonucleotide primers for Rotavirus A, B and C., Results: Four subjects were found positive for parasites. Eighty-three (10.3%) samples were found positive for Salmonella (46 isolates), Shigella (26 isolates), Campylobacter jejuni (7 isolates), and Enteropathogenic Escherichia coli (4 isolates). Rotavirus was found in 91 (13.9%) samples and 4 samples (0.6%) were found positive for adenovirus. Out of 200 samples examined by reverse transcription-polymerase chain reaction, 73 (36.5%) were positive for group A rotavirus., Conclusions: Rotavirus type A appeared to be the most common single agent in our pediatric population, followed by the classical bacterial pathogens. Adenovirus and parasites appeared to play a very minor role in diarrhea. Thus, we suggest the introduction of rotavirus diagnostic tests in microbiological examination of diarrheic stools of children below 3 years of age.

An essential element in the control of tuberculosis is the rapid, sensitive and specific identification of the causative agent. Until now, screening and diagnosis are largely based on clinical signs, radiological examination, tuberculin tests, sputum examination under the microscope, or culture for mycobacteria. Tuberculin tests lack specificity and only give an indication of previous exposure to mycobacteria. Direct microscopic examination of sputum is neither specific nor sensitive enough, and mycobacterial isolation is time-consuming. As an alternative to these classical methods, new nucleic acid-based technologies show promise as a more rapid, sensitive, and specific means of identification of mycobacteria. Two commercial standardized nucleic acid-based amplification techniques have been reported to yield reliable results within 5 to 7 hrs. Roche Amplicor MTB (Roche Diagnostic System, Somerville, N.J.) and Gen-Probe AMTB (Gen-Probe Inc., San Diego, Calif.). The amplified target is part of the 16S rRNA gene which is common to all the mycobacteria. An attempt has been made to describe the use of the target DNA, SenX3-RegX3, in a multiplex PCR to detect and differentiate M. tuberculosis from other mycobacteria directly from clinical specimens.

Background/aim: There is evidence of a possible etiological role of human papillomaviruses (HPVs) in the development of esophageal tumors. Loss of function of the wild-type p53 tumor suppressor gene product by binding to E6 oncoproteins of high-risk HPVs is considered an important event in tumor development. The aim of this study was to verify the prevalence of HPV infection and p53 mutation in esophageal tumor tissue samples and in the adjacent normal mucosa in patients from a high-risk area in Italy., Methods: DNA from 33 biopsy specimens (17 tumor sample biopsies and 16 samples of adjacent normal mucosa) was screened for HPV DNA using two polymerase chain reaction based procedures. Restriction fragment length polymorphism analysis was used for typing. Screening of p53 mutations was performed with polymerase chain reaction-single strand conformation polymorphism analysis and DNA sequencing., Results: Overall, 8 of 17 patients presented HPV DNA; HPV 16 was detected in 4 of 8 samples. Samples from tumors and adjacent mucosa were positive for mucosal HPVs in 7 of 17 and 4 of 16 cases, respectively. In 1 case, HPV DNA was detected in the normal mucosa only. None of the samples contained HPVs of the epidermodysplasia verruciformis or cutaneous groups. Mutations of p53 were detected in two HPV DNA negative samples. In both cases, the mutation was present in the tumor only., Conclusions: Our results are in favor of the involvement of both aberrant p53 expression and HPV infection in the development of esophageal tumors. The high HPV infection rate in patients from a high-risk region suggests that subjects harboring HPVs (in particular HPV 16) in the esophagus should be considered at risk of esophageal malignancies., (Copyright 2001 S. Karger AG, Basel)

Gram-negative anaerobes belonging to the genera Fusobacterium, Prevotella and Porphyromonas were investigated for the presence of tetQ and ermF, which have been shown to be spread by conjugal elements. One hundred isolates from either sites of infection or various body sites in healthy subjects were studied. PCR was used to detect tetQ, and DNA-DNA hybridization studies on EcoRI chromosomal digests were undertaken to detect the presence of tetQ and ermF. Antibiotic sensitivity assays were performed on selected isolates to detect tetracycline, erythromycin and penicillin resistance. Twenty Fusobacterium isolates lacked tetQ, and were tetracycline sensitive. Twenty per cent of Prevotella spp. isolates both from clinical specimens and from healthy subjects were found to possess tetQ. Of 20 Porphyromonas isolates tested, one (Porphyromonas levii) from a case of bacterial vaginosis was shown to possess tetQ in the chromosome. The presence of tetQ was always associated with tetracycline resistance. Four isolates of Prevotella melaninogenica and one isolate of Prevotella were ermF-positive, although expression of erythromycin resistance was not consistently associated with detection of this gene. Antibiotic resistance phenotypes of Prevotella isolates were shown to be related to specific chromosomal restriction patterns by hybridization studies: tetracycline resistance and tetracycline/erythromycin resistance are conferred by Bacteroides tetracycline-resistant ERL elements, whereas the tetracycline/penicillin resistance phenotype could be due to spread of elements identified in Prevotella only. Tetracycline/erythromycin-resistant and tetracycline/erythromycin/penicillin-resistant P. melaninogenica isolates were found in this study. It appeared that the presence of tetQ and ermF in Bacteroides and Prevotella contributed to the persistence of antibiotic resistance isolates within the host and to potential spread to other organisms through conjugal elements.