Shigella flexneri has been the most frequent cause of shigellosis in children in Iran. To evaluate the changes in frequency of serogroups, 302 Shigella species were isolated in 2003 from hospitalized children, aged less than 12 years, with acute diarrhoea in Tehran, Iran. The number of collected S. sonnei, S. flexneri, S. boydii, and S. dysenteriae isolates was 178 (58.9%), 110 (37.4%), 10 (3.3%), and 4 (1.3%) respectively. Most (94%) S. sonnei isolates were resistant to co-trimoxazole. They were, however, relatively or completely sensitive to 15 commonly-used antibiotics. The extracted plasmids showed 12 different profiles with two closelyrelated patterns constituting 70% of the total isolates. Ribotyping, using PvuII, HindIII or SalI restriction enzymes, generated a single pattern for all S. sonnei isolates. Data suggest that S. sonnei has become the predominant serogroup in children in the hospitals of Tehran.

OBJECTIVES:Leptospirosis is a zoonosis caused by leptospires, in which transmission occurs through contact with contaminated biological fluids from infected animals. Rodents can act as a source of infection for humans and animals. The disease has a global distribution, mainly in humid, tropical and sub-tropical regions. The aim of this study was to compare culture assays, the microscopic agglutination test (MAT), polymerase chain reaction (PCR), and nested PCR (n-PCR), for the diagnosis of leptospirosis in rodents in Mazandaran Province, northern Iran.METHODS:One hundred fifty-one rodents were trapped alive at 10 locations, and their urine and kidney samples were collected and used for the isolation of live Leptospira. The infecting serovars were identified and the antibody titres were measured by MAT, using a panel of 20 strains of live Leptospira species as antigens. The presence of leptospiral DNA was evaluated in urine and kidney samples using PCR and n-PCR.RESULTS:No live leptospires were isolated from the kidney and urine samples of the rodents. Different detection rates of leptospirosis were observed with MAT (21.2%), PCR (11.3%), and n-PCR (3.3%). The dominant strain was Leptospira serjoehardjo (34.4%, p=0.28), although other serotypes were also found. The prevalence of positive leptospirosis tests in rodents was 15.9, 2.6, and 2.6% among Rattus norvegicus, R. rattus, and Apodemus sylvaticus, respectively.CONCLUSIONS:Leptospirosis was prevalent in rodents in Mazandaran Province, northern Iran. MAT was able to detect leptospires more frequently than culture or PCR. The kidney was a more suitable site for identifying leptospiral DNA by n-PCR than urine. Culture was not found to be an appropriate technique for clinical diagnosis.

Significance and Impact of the Study: Several aetiologic mechanisms are suspected in IBD, including an imbalance between pro-inflammatory and anti-inflammatory signal transduction pathways. JAK/STAT plays various roles in association with different types of cytokines that might influence the status of IBD. Balancing and modulating the immune system and strain-specific anti-inflammatory abilities are two of the crucial features of probiotics. Bifidobacterium spp. could play an important role in modulating JAK/STAT and NF-kB signalling pathways.

Leptospirosis as a zoonotic disease is caused by Leptospira bacteria. Transmission occurs by contact with contaminated biological fluids of the infected animals. Rodents are major sources of infection for humans or other animals. The disease is distributed mainly in tropical regions with rainfall like northern part of Iran. The aim of this study was to find association of prevalent Leptospira species with different rodents of three Northern Provinces in Iran using microscopic agglutination test (MAT). Methods: In this study, 404 rodents were captured alive at 10 different parts of each Mazandaran, Gilan and Golestan Provinces. Identification of the infecting serovars and the antibody titers were done by MAT in the sera samples using a panel of 20 strains of live Leptospira spp. as the source of antigens. RESULTS: Antibodies against one or more serovars were detected in 94 (23.27%) sera at dilution ≥1:200 and 76.73% were detected to be negative. The prevalent Leptospira serovars were detected as L. autumnalis (25.53%), L. serjoehardjo (24.47%) and L. cynopteri (6.38%). The majority of rodents were identified during this study in three provinces included Rattus norvegicus (67.33%), Apodemus sylvaticus (13.86%) and Rattus rattus (13.61%). The common prevalent rodent in three provinces was Rattus norvegicus, which was associated with L. serjoehardjo in Mazandaran (81.8%), L. autumnalis in Gilan (67.2%) and L. canicula in Golestan (50.0%). Conclusion: The dominant srovars of leptospira were L. autumnalis, L. serjoehardjo and L. cynopteri and the most prevalent rodents as reservoir were Rattus norvegicus, Apodemus sylvaticus and Rattus rattus in three Northern provinces of Iran. The results indicated a moderate prevalence of leptospirosis in rodents during this study in north of Iran. This study provided the first epidemiological data about the association between leptospirosis with rodents in Iran.

Background: Inflammatory bowel disease is a chronic inflammatory disease of the gastrointestinal tract. The gut microbiota is an important factor in the pathogenesis of IBD. Due to a link between the gut microbiota and IBD, studying microbiota changes using an accurate, sensitive and rapid method for detection of the disease seems necessary. This study aimed to compare the composition of gut microbiota in three groups of people, including IBD patients, CIBD, and healthy groups. Methods: For this study, 45 stool samples (15 from each group) were collected. Using real-time PCR, the abundance of 11 bacterial 16S rRNA gene sequences was examined. Results: In the IBD group, the number of three bacterial phyla, including Firmicutes, Actinobacteria, and Bacteroidetes, decreased (p < 0.01, p < 0.01, and p < 0.001, respectively), while the population of γ-Proteobacteria increased significantly (p < 0.0001). In the CIBD group, the number of Actinobacteria enhanced (p < 0.01), but that of Bacteroidetes and Firmicutes decreased (p < 0.01, and p < 0.05, respectively). Conclusion: Findings of this study indicate that decrease in Firmicutes and increase in γ-Proteobacteria could be used as an indicator of IBD instead of employing invasive and costly detection methods such as colonoscopy and other tests.