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Salmonella enterica has become progressively resistant to antimicrobial agents worldwide as a result of genes carried on different classes of integrons. The aim of the current study was to investigate the molecular diversity of these integrons and their association with antimicrobial resistance in clinical S. enterica isolates from Tehran, Iran. Antimicrobial susceptibility testing was performed according to the Clinical and Laboratory Standards Institute. The presence of integrons was investigated by PCR using specific primers. Integrons were detected in 65 (47.1%) strains, with classes 1 and 2 being observed in 54 (39%) and 11 (8%) strains, respectively. Integron-positive isolates belonged to seven different S. enterica serovars, and all showed a multidrug-resistant (MDR) phenotype. Our findings show that integrons are widely disseminated among S. enterica strains from Tehran. Furthermore, the results that class 1 integrons were more prevalent than class 2 in Salmonella isolates, and that a statistical association with MDR patterns was observed, suggest that they are more likely to be important in conferring a resistant phenotype to Salmonella strains.

BACKGROUND: Urinary tract infection is the most common health problem affecting millions of people each year, mainly caused by a large genetically heterogeneous group of Escherichia coli called uropathogenic E. coli This study investigates the genotypic analysis of E. coli strains isolated from patients with cystitis and pyelonephritis. METHODS: During 2008-2009, 90 E. coli strains were analyzed, consisting of 48 isolates causing pyelonephritis in children and 42 isolates causing cystitis. Having identified the strains by standard methods, they were subtyped by pulsed field gel electrophoresis (PFGE) and their corresponding patterns were compared using dendrogram. RESULTS: Sixty five PFGE profiles were obtained from the genome of E. coli strains by this genotyping method. Thirty six and thirty three patterns were obtained for pyelonephritis and cystitis, respectively. Most strains exhi-bited twelve and thirteen bands and the patterns with eight or nineteen bands had the lowest rate. Genome sizes of the strains were between 1610-4170 kbp. CONCLUSION: With due attention to these results, genetic patterns showed that the strains had different clonalities and it could be suggested in some cases that the strains causing pyelonephritis or cystitis have common patterns and different diseases could be explained by different gene factors.

Pseudomonas aeruginosa is an important life-threatening nosocomial pathogen and plays a prominent role in serious infections in burned patients. The current study was undertaken to characterize P. aeruginosa strains isolated from burned patients in Tehran, Iran. The study was conducted in a major burn center in Tehran, Iran in 2007. A total of seventy specimens obtained from different clinical origin with positive culture results for P. aeruginosa were included in the study. Antimicrobial susceptibility test was performed according to the standard CLSI guideline. The relationship between the strains was also determined using antimicrobial drug resistance pattern analysis and plasmid profiling. All strains were multi drug resistant. The percentage of resistance to tested antibiotics was: imipenem 97.5%, amikacin 90%, piperacillin 87.5%, ceftizoxime 72.7%, gentamicin 67.5%, ciprofloxacin 65%, ceftriaxone 60%, and ceftazidime 57.5%. Thirteen resistant phenotypes were recognized, R3 (TET, IPM, AMK, CIP, PIP, GM, CAZ, CRO, CT) was the predominant resistance pattern seen in 27.5% of isolates. Results obtained from E-test showed that 100% of P. aeruginosa strains were resistant to cefoxitin, 97% to cefotetan, 93% to ticarcillin, 89% to ticarcillin/clav, 76% to gentamicin and imipenem, 63% to piperacillin, 49% to tetracycline, and 20% to meropenem. Nine different plasmid profiles were observed among the strains. The current study showed an increase rate of resistance for some antibiotics tested among P. aeruginosa strains isolated from burned patients in Tehran. A combination of antibiotic susceptibility testing and profile plasmid analysis, which are relatively cheap and available methods, showed to be useful to characterize the clinical strains of P. aeruginosa isolated from burned patients in Iran.

Some adipocytokines are cardioprotective or pro-inflammatory for cardiovascular system. Chronic infection with Chlamydia pneumoniae and Helicobacter pylori has been also considered as novel risk factors for atherosclerosis. The main aim of the current population-based study is to investigate the potential link between circulating adipocytokines and Chlamydia pneumoniae or Helicobacter pylori IgG seropositivities. A total of 250 healthy postmenopausal women who participated in a prospective cohort study were evaluated for IgG antibodies directed against C.pneumoniae and H. pylori. Omentin-1, visfatin, adiponectin, and high sensitivity C-reactive protein were measured by highly specific enzyme-linked immunosorbent assay methods. The prevalence of IgG antibodies against C. pneumoniae and H. pylori among the studied population was 20.4% (51 women) and 57.2% (143 women), respectively. There were no significant differences in adipocytokine levels between H. pylori IgG seropositive and H. pylori seronegative subjects. Similar results for visfatin and omentin-1 were found when C. pneumoniae IgG seropositive were compared with C. pneumoniae IgG seronegative subjects. However, in general linear model adjusted for age, body mass index and hs-CRP levels revealed significant difference between C. pneumoniae seropositive and C. pneumoniae seronegative subjects for circulating adiponectin. In conclusion, Chlamydia pneumoniae IgG seropositivity was associated with higher adiponectin levels in postmenopausal women. The elucidation of interaction mechanism of Chlamydia pneumoniae and a cardioprotective adipocytokine (adiponectin) will be useful in future therapeutic strategies.

Hepatitis B virus (HBV) infection, one of the major health priorities, accounts approximately for 350 million chronic cases and a global total of 33 million people were living with human immunodeficiency virus (HIV) in the world.Co-infection with HIV and the HBV presents a significant challenge to health care providers, with different prevalence rates in different parts of the world. It is important to screen all HIV infected individuals for HBV infection and reverse. Infection with HBV becomes more violent in patients co-infected with human immunodeficiency syndrome. HIV/HBV co-infected individuals are at increased risk of chronic hepatitis, cirrhosis, and hepatocellular carcinoma, and of experiencing HAART toxicity. In this review, the latest statistics on epidemiology of HIV, HBV and their co-infection has been presented along with prominent characteristics of HBV. Transmission routes which are the common between HBV and HIV are described and the most important ones are described according to the regional and age features. Also, there is a series of actions being performed once HBV infections occur to prevent HIV or to diagnose if the HBV-infected individuals are also infected with HIV. As in treatment case, some of the frequent treatment methods including applying interferon and using nucleoside and nucleotide analogues have been discussed. Finally, we would explain the new recommendations for treating patients who were co-infected with HBV and HIV, including staging HBV and HIV treatment, based on the stage of each disease. It also outlines the optimal treatment options, whether the patient is treated for HBV first, HIV first, or HIV and HBV together.

BACKGROUND: Diabetes mellitus (DM) is a very well-known risk factor for development of atherosclerosis, and it has been hypothesized that poor glycemic control and hyperglycemia plays a major role in this process. In the current study, we aimed to evaluate the associates of poor glycemic control in Iranian patients who have already undergone coronary artery bypass grafting (CABG), with especial focus on the inhabitation of infectious agents within the coronary arterial wall. METHODS: In January 2010, 52 consecutive patients with type 2 DM who undergone CABG at the Department of Cardiovascular Surgery of Baqiyatallah University of Medical Sciences (Tehran, Iran) were included into this cross-sectional study and biopsy specimens from their coronary plaques were taken and analyzed by polymerase chain reaction (PCR) methods for detecting Helicobacter species, cytomegalovirus (CMV) and Chlamydia pneumoniae, and their potential relation to the glycemic control status in these patients. RESULTS: Compared to that in diabetic patients with mean fasting blood sugar (FBS) levels FBS < 126, atherosclerotic lesions in type 2 diabetic patients with poor glycemic control (FBS > 126) were significantly more likely to be positive for CMV PCR test (41% vs. 9%, respectively; P = 0.05). In laboratorial test results, mean triglyceride level was significantly higher among patients of poor glycemic control (168 ± 89 vs. 222 ± 125 mg/dl, respectively; P = 0.033). Hypertension was also significantly more prevalent in this population (73% vs. 36%, respectively; P = 0.034). CONCLUSION: Type 2 diabetic patients with poor glycemic control can be at higher risk for developing CMV infection in their coronary arterial wall, which can promote atherosclerosis formation process in this patient population. According to the findings of this study, we recommend better control of serum glucose levels in type 2 diabetic patients to prevent formation/progression of atherosclerosis. Keywords: Diabetes Mellitus, Hyperglycemia, Coronary Artery, Cytomegalovirus, Infection&nbsp

Background: Many species of sustainable mycotoxin-producing fungi are considered as dangerous agents for humans. Bread is one of the materials exposed to fungal infection and molds are amongst the most important pollutant microbial and chemical mycotoxin-producing agents of bread. In this study, the microbial and chemical contamination of recycled waste breads and the types of produced mycotoxins at two areas of Tehran municipality, Iran, were investigated. Methods: Using fungal culture media, twenty samples of waste bread were analyzed for microbial contaminations. To recognize contamination to mycotoxins, high-performance liquid chromatography (HPLC) method and fuorescence detector (FLD) were used. Findings: All but one sample were contaminated to mold infections such as Aspergillus, Penicillium, and yeasts including Geotricum candidum, Candidia albicans and Saccharomyces cerevisiae. Eight samples were contaminated to aflatoxins, ochratoxin A and deoxynivalenol, whereas none of them showed contamination with zearalenone. Conclusion: The results indicated that presence of microbial and toxic contamination in bread waste is inevitable, which is harmful for human health. The sanitary control of food waste to reduce or eliminate microbial hazards in food recycling is necessary.

Background: Salmonella enterica serovar enteritidis is currently the most frequent serovar causing salmonellosis in humans. The incidence of gastrointestinal infections caused by S. enteritidis increased during the last decade. The aim of this study was to evaluate the genetic diversity of S. enteritidis isolates from Tehran (Iran) hospitals using ribotyping methods. Methods: In a descriptive study from April 2008 to December 2011, clinical samples such as fecal and blood specimens of the cases having symptoms of salmonellae infection were collected from different hospitals in Tehran. Salmonella isolation was carried out by bacteriological and serological methods. The relationship between the strains was determined using ribotyping. Finding: Of 68 Salmonella spp. strains, 29 isolates were S. enteritidis. Ribotyping was able to differentiate all isolates. The size of the bands ranged from 1.4 to 16.8 kb in all ribotypes. S. enteritidis isolates were divided into three clusters (1d to 3d). Most strains (20) belonged to the 1d cluster. Conclusion: Our results indicated that S. enteritidis strains circulating in Tehran mainly belong to a limited ribotype. Keywords: Salmonella enteritidis, Salmonellosis, Ribotyping

BACKGROUND AND OBJECTIVE: Several clinical, laboratory and imaging modality was suggested for distinguishing infected from non-infected form of diabetic foot ulcer (DFU). This study was performed to compare erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and white blood cell (WBC) count as inflammatory marker in between infected and non-infected diabetic foot ulcer.METHODS: A process-research study was conducted on 90 individuals at the Baqiyatallah hospital (Tehran, Iran) between 2009 and 2010. The first group contained infected DFU according to the criteria of IDSA-IWGDF (n=30), second group contained non-infected DFU (n=30) and third group contained healthy individuals (n=30). Demographic, clinical and laboratory (ESR, CRP and WBC count) findings were compared between groups.FINDINGS: The mean and standard deviation (SD) of CRP in healthy, infected and non-infected diabetic foot groups were 1±1.4, 46.5±46.5 and 9.2±5.3 mg/dLit, respectively (p

Objective(s): Brucella spp. are facultative intracellular pathogens which can stay alive and multiply in professional and nonprofessional phagocytes. Immunity against Brucella melitensis involves antigen-specific CD4+ and CD8+ T-cells activation and humoral immune responses. Due to negative aspects of live attenuated vaccines, much attention has been focused on finding Brucella-protective antigens to introduce them as potential subunit vaccine candidates. Materials and Methods: A chimeric gene encoding trigger factor (TF), Omp3148-74 and BP2687-111 fragments (TOB) from B. melitensis was successfully cloned, expressed in Escherichia coli BL21-DE3 and purified by Ni-NTA agarose column. Antibodies to recombinant TOB (rTOB) have been investigated in Brucella-infected human sera and a pool serum prepared from B. melitensis-vaccinated rabbits. Results: Our results showed that the immunized rabbit pool serum strongly reacted with rTOB. In addition, antibodies against rTOB were detectable in 76.5% of sera obtained from infected patients. Conclusion: These findings suggest that rTOB may provide a potential immunogenic candidate which could be considered in future vaccine studies.

Background: Epidemic and endemic cholera is a major public health problem for many countries. Aim of this study was to evaluate AP-PCR for investigation of clonal relatedness among the strains of Vibrio cholerae recovered from an out­break occurred in different parts of Iran in 2005. Methods: The study was conducted during the cholera outbreak occurred in some of provinces in Iran in summer 2005. Bac­terial isolation and identification was carried out according to the standard bacteriological methods. Arbitrarily primed PCR (AP-PCR) used to study the genetic relatedness between the V.cholerae isolates. Results: Thirty-nine isolates of V.cholerae O1 were identified. All isolates belonged to serotype Inaba. AP-PCR could dif­ferentiate the isolates into five groups. AP-PCR cluster types 1 and 2 were the most prevalent groups, accounting for 36% and 41%, respectively, of V.cholerae isolates. Conclusion: The most of epidemic strains of V.cholerae O1 isolated in the year 2005 could be attributed to two pre­dominant clusters including AP-PCR cluster types 1 and 2 accounting for more than 77% of isolates. In conclusion, a few epidemic clones were responsible for the apparently epidemic occurrence of cholera in provinces studied.

Background: Multiple sclerosis (MS) is a demyelinating autoimmune disease, with an unclear mechanism, and characterized by axonal damage, demyelination and increase inflammatory. Recently, it has been found that leptin plays a role in the pathogenesis of multiple sclerosis. The current study aimed to compare serum level of leptin and aerobic capacity in relapsing and remitting duration in women with multiple sclerosis. Methods: 32 women with multiple sclerosis including 12 in relapsing and 20 in remitting phases participated in this study. Serum level of leptin was assessed using enzyme-linked immunosorbent assay (ELISA) kit and aerobic capacity was measured using ergometer cycle incremental test. Independent t and Pearson correlation tests were used for data analysis at the significant level of P ≤ 0.05. Findings: Data indicated that leptin was higher in relapsing group; but, aerobic capacity was higher in remitting group (P ≤ 0.05). In addition, a negative and significant correlation was observed between leptin and aerobic capacity in both groups and leptin and body mass index in remitting group (P ≤ 0.05). Conclusion: According to the result, increasing of leptin and decreasing of aerobic capacity associated with relapsing in patients with relapsing-remitting multiple sclerosis.

The present study was conducted to investigate serotype distribution, antimicrobial resistance patterns, carriage of class 1 integron, and clonality of Salmonella strains isolated from patients aged 0-12 years in Tehran, Iran, during 2007-2008. A total of 139 Salmonella isolates were studied. Salmonella serotypes Enteritidis, Infantis, and Typhimurium included 84.9% of isolates, Enteritidis accounting for 41.7%. The most prevalent resistances were to doxycycline (64.7%), nalidixic acid (61.2%), tetracycline (51.8%), and streptomycin (42.8%). Fifty-three (38.1%) isolates contained class 1 integron. Eight different gene cassettes were identified, aadA1 being the most frequently encountered. Pulsed-field gel electrophoresis showed that integron-positive Salmonella strains belonging to serotypes Infantis, Enteritidis, and Typhimurium were attributed to two, three, and five different pulsotypes, respectively. The findings indicated that the distribution and drug resistance pattern of most prevalent Salmonella serotypes were broadly similar to that reported globally from human isolates. Presence of class 1 integrons was common among Salmonella serotypes in Tehran, Iran. Concurrent clonal expansion and horizontal transmission events seem to contribute to increase in drug resistance prevalence among Salmonella serotypes.

We evaluated the performances of a newly designed real-time polymerase chain reaction (PCR) assay using TaqMan® probes to detectSalmonellaTyphi. TaqMan® real-time PCR assays were performed by designed primers and probe based on thestaGgene for detectingS.Typhi. The specificity of the assay was evaluated on 15Salmonellaserovars. The analytical specificity was evaluated on 20 non-Salmonellamicroorganisms. The analytical sensitivity was assessed using decreasing DNA quantities ofS.Typhi ATCC 19430. Finally the detection capability of the TaqMan® real-time PCR assay on isolates recovered from patients withSalmonellainfections was compared to the conventional PCR assay. OnlyS.Typhi strain had positive results when subjected to the assay using Typhi-specific real-time PCR. No amplification products were observed in real-time PCR with any of the non-Salmonellamicroorganisms tested. The TaqMan® real-time PCR was more sensitive than the conventional PCR. In conclusion, we found that the easy-to-use real-time PCR assays were faster than conventional PCR systems. ThestaG-based TaqMan® real-time PCR assay showed to be specific and sensitive method for the safe and rapid detection of theS.Typhi.

Microbial typing is often employed to determine the source and routes of infections, confirm or rule out outbreaks, trace cross-transmission of healthcare-associated pathogens, recognize virulent strains and evaluate the effectiveness of control measures. Conventional microbial typing methods have occasionally been useful in describing the epidemiology of infectious diseases. However, these methods are generally considered too variable, labour intensive and time-consuming to be of practical value in epidemiological investigations. Moreover, these approaches have proved to be insufficiently discriminatory and poorly reproducible. DNA-based typing methods rely on the analysis of the genetic material of a microorganism. In recent years, several methods have been introduced and developed for investigation of the molecular epidemiology of microbial pathogens. Each of them has advantages and limitations that make them useful in some studies and restrictive in others. The choice of a molecular typing method therefore will depend on the skill level and resources of the laboratory and the aim and scale of the investigation. This study reviews the most popular DNA-based molecular typing methods used in the epidemiology of bacterial pathogens together with their advantages and limitations.

To investigate global epidemiology of Shigella sonnei, we performed multilocus variable number tandem repeat analysis of 1,672 isolates obtained since 1943 from 50 countries on 5 continents and the Pacific region. Three major clonal groups were identified; 2 were globally spread. Type 18 and its derivatives have circulated worldwide in recent decades.

Shigellosis, one of the most common bacterial diarrhoeal diseases, is endemic throughout the world. It is one of the major causes of morbidity in children with diarrhoea in Iran [1-4]. Antibiotic therapy is useful and effective for shigellosis. Treatment is critical for persons with severe disease, particularly children and immunosuppressed patients. Use of an appropriate antibiotic therapy can shorten the duration of symptoms, significantly reduce the risk of transmission, and also prevent potentially lethal complications [5-7]. However, high frequencies of resistance in

Background Shigella spp. are major cause of diarrhoeal disease in both developing and developed countries. Shigella sonnei is the serogroup of Shigella most frequently responsible for sporadic and epidemic enteritis in developed countries. In recent years the emergence and spread of S. sonnei biotype g carrying class 2 integron have been frequently reported in many countries. Recently, S. sonnei has been reported as the prevalent serogroup of Shigella in Iran. The present study was carried out to investigate phenotypic and genetic characteristics of Shigella sonnei isolates identified in the years 2002 and 2003 in Tehran, Iran. Methods Biotyping, drug susceptibility testing, pulsed field gel electrophoresis (PFGE) and analysis of class 2 integrons have been carried out on 60 S. sonnei isolates, including 57 sporadic isolates from paediatric cases of shigellosis occurring in 2002 and 2003, two sporadic isolates recovered in 1984 and the ATCC 9290 strain. Results Biotype g and resistance to streptomycin, sulfamethoxazole-trimethoprim and tetracycline were exhibited by 54 of the 57 recent isolates. Of the 54 biotype g isolates, 28 exhibited a class 2 integron of 2161 bp, and 24 a class 2 integron of 1371 bp, respectively. Class 2 integrons were not detected in four isolates only, including the two endemic isolates recovered in 1984 and two strains from recent sporadic cases. PFGE divided the strains into eight pulsotypes labeled A to H, three major pulsotypes – A to C – including the large majority of the recent sporadic S. sonnei isolates. Pulsotypes A and C were the most prevalent groups, accounting for 41.6% and 35.0%, respectively, of the isolates under study. Conclusion The results suggest that biotype g, class 2 integron carrying S. sonnei are prevalent in our geographic area. S. sonnei isolated in the years 2002 and 2003 could be attributed to a few predominant clusters including, respectively, strains with pulsotypes B and C carrying a 2161 bp class 2 integron, and those having pulsotype A and a 1371 bp class 2 integron. A few epidemic clones are responsible for the apparently endemic occurrence of shigellosis in Tehran, Iran.

Uropathogenic Escherichia coli are the most common cause of urinary tract infections,and quinolones-resistant strains cause growing concern in developing countries. This study provides relevant data in relation to the molecular epidemiology of these isolateswith respect to the distribution of integron among them and in doing so, to control the infections and adopt efficient strategies. This study was performed on 96 strains of E. coliisolated from patients with community acquired urinary tract infections in Jahrom, Iran. Having determined the antibiotic susceptibility patterns, isolates were resistant to quinolones (Ciprofloxacin, Norfloxacin and Nalidixic acid) screened for integron classes by polymerase chain reaction (PCR). Then the genetic patterns of the strains were compared by pulsed field gel electrophoresis. Of the 96 samples, 30 were resistant to at least one of the above mentioned antibiotics. Integrons were detected in 20.8, 25 and 25% of the Nalidixic acid, Ciprofloxacin and Norfloxacin resistant isolates, respectively. By using pulsed field gel electrophoresis among the 30 samples, we obtained 30 genetic patterns. The patterns revealed no clonal relationships between the strains. The gene cassettes observed in class 1 and 2 integrons did not correlate completely with the quinolone resistance observed in these isolates. Key words: Quinolones-resistant uropathogenic Escherichia coli, pulsed field gel electrophoresis, integrons.

Background and Objectives: The emergence of extended-spectrum β-lactamase (ESBL)-producing Shigella spp. is of increasing clinical concern specially in children worldwide. The aim of this study was to investigate the occurrence of extended-spectrum β-lactamase producing Shigella spp. in Tehran, Iran. Materials and Methods: The study included all Shigella isolates recovered from pediatric patients aged less than 12 years admitted to a major pediatric hospital in Tehran, Iran, from 2008 to 2010. Bacterial identification, antimicrobial susceptibility testing, extended spectrum β-lactamases (ESBLs) screening and confirmatory tests were performed according to the standard guidelines. Conjugal transfer experiments and plasmid analysis were also carried out. Polymerase chain reaction and sequencing were used to identify the genetic determinants responsible for ESBL production. Results: Four out of 55 Shigella isolates, including three S. sonnei and one S. flexneri, showed an ESBL-positive phenotype. Plasmid transfer of the ESBL phenotype was successful for the S. flexneri isolate only. By PCR and sequencing, one S. sonnei isolate tested positive for the CMY-59 gene, while the other two S. sonnei and the S. flexneri isolates tested positive for the blaTEM-1 and blaCTX-M-15 genes. Conclusion: We found the prevalence of ESBL producing Shigella isolates was higher than detection rates observed in many other countries. Our finding raise concerns about the dissemination of ESBL among the strains of endemic S. sonnei throughout the country, because this species is now the most frequently isolated Shigella species in Iran and shigellosis by such strains in the community can pose a significant threat to patients and presents a challenge for disease management.

Background: Shigellosis is one of the major causes of morbidity in children with diarrhea in Iran. The present study was undertaken to characterize apparently sporadic Shigella boydii strains isolated from pediatric patients in Iran. Findings: Ten S. boydii strains isolated from pediatric cases of gastroenteritis and acute diarrhea in Tehran between December 2002 and November 2003 were submitted to serotyping, antimicrobial susceptibility testing, plasmid profile analysis, ribotyping and pulsed field gel electrophoresis (PFGE). Seven isolates were attributed to serotype 2, whereas the remaining three belonged to serotypes 14, 18, 19, respectively. Six drug resistance phenotypes (R1 to R6) were defined with R4 - streptomycin (STR), ampicillin (AMP), sulfamethoxazole-trimethoprim (SXT) - being the most prevalent. Plasmid analysis resulted in seven different plasmid profiles with one to five DNA bands. All strains, but one, shared the same ribotype, but PFGE differentiated them in four groups. Conclusion: Based upon ribotyping and PFGE results, endemic circulation of S. boydii in Tehran, Iran, could be attributed to a few clones. Resistance pattern and plasmid profile analysis proved to be very effective in discriminating apparently unrelated strains of S. boydii