[Study on epidemiological patterns of Mycobacterium tuberculosis by fingerprinting]

Despite the availability of effective anti tubercle chemotherapy for more than 50 years and major advances in the biology of M. tuberculosis, TB remains the leading cause of adult mortality attributable to a single pathogen. The analysis of tuberculosis and tracing of the source of infection require the ability to discriminate among Mycobacterium tuberculosis strain. In present study Restriction Fragment Length Polymorphism [RFLP] analysis was used to study the molecular epidemiology of tuberculosis in Tehran. Mycobacterium tuberculosis isolates from 292 patients with culture positive tuberculosis during 2002-2003. Extraction of bacterial DNA and DNA fingerprinting with RFLP using lS6110 as probe, was performed by standard protocols. The digested DNA is separated according to fragment size on agarose gel by electrophoresis and southern transferred on to a membrane. The DNA probe was labeled with [HRP] and hybridizing to the genomic targets. Among 292 culture M. tuberculosis, 232 [79.4%] belonged to clusters and 60 [21.6%] did not. 39 Drugs resistant M. tuberculosis isolates were examined 33%of these were identical pattern lS6110. 4.9% of the isolates represented the Beijing genotype. Based on the obtained data it appears that tuberculosis among the study population in Tehran mainly from reactivation of latent infection

Plasmid profile, antibiotic resistance, and phenotypic virulent strains of S. flexneri

Shigellosis is an acute gastroenteritis caused by Shigella species. The purpose of this study was to determine plasmid profile, antibiotic resistance and phenotypic virulent by Congo red between S. flexneri strains. The isolated bacteria were identified by standard bacterial and biochemical methods. Plasmids were isolated by alkaline lysis method. Antibiotic susceptibility test was performed according to "kirby-Bauer" method. Serological reactions were carried by slide agglutination tests with both polyclonal and monoclonal antiserum kits. Virulent strains were isolated on a TSA plate contained Congo red dye concentration. From 350 isolated Shigella species, 142 [40.57%] were S. flexneri. Eleven distinct plasmid profile patterns were identified. Of S. flexneri isolates, 95% were resistant to tetracycline, 85.6% to SXT and 75.3% to ampicillin. All the isolates were sensitive to ciprofloxacin. Our results showed that 39% were serotype II. 45.56% of S. flexneri were Congo red positive. Antibiotic resistant determination in each case may prevent drug resistance increase. Since Congo red binding test is cheap and simple it can be used to determine virulence properties of S. flexneri

[ prevalence of acinetobacter in sergical ICU in Rasoul Akram Hospital in 2004-2005]

Acinetobacters are opportunistic pathogens. Nowadays these bacteria are are among the pathogens causing nosocomial infections, so the aim of this study was to identify of acinetobacter in surgical Intensive Care Unit [ICU] in Rasoul Akram hospital and to assess the possibility of transferring antibiotic resistance by conjugation method. In this study 100 samples were collected from respiratory tubes, respiratory secretion, intensive care unit room, food trays, beds' wheels, serum tubes and bed sheets of patients in hospitalized at Rasoul Akram hospital. Bacteria were isolated and identified by using standard bacteriological methods. After identification, antibiogram tests were done performed to determine the antibiotic sensitivity. After this phas, conjugation were done between donor and recipient strains in BHI broth medium. From all 100 collected samples, 21 samples acinetobacter was isolated. Isolated acinetobacters showed 100% resistance to rifampin, penicillin, erythromycin and tetracycline, 95/2% resistance to gentamicin, nalidicsicacid, amikacin, seftizokcim, streptomycin, sephazolin, and cloroamphenicol, 90/5% resistance to seftazidim and cyprofelocsazin. They showed maximum sensitivity 28/6% to sulfumetoxasol. Isolation of acinetobacter from surgical intensive care unit showed the contamination of this unit with this opportunistic pathogen bacteria. So more care for sterilization of this unit and tools that are used are suggested. Suitable use of antibiotics for prevention of producing multiresistant bacteria and nosocomial infections are necessary too

Study of lactobacillus as probiotic bacteria

Because of inhibitory effect, selected probiotic lactobacilli may be used as biological preservative, so, the aim of this study was to present some data on lactobacillus as probiotic bacteria. Lactic acid bacteria were isolated from sausage. Each isolate of lactobacillus species was identified by biochemical tests and comparing their sugar fermentation pattern. Antibacterial activities were done by an agar spot, well diffusion and blank disk method. Enzyme sensitivity of supernatant fluid and concentrated cell free culture after treatment with alpha-amylase, lysozyme and trypsin was determined. The isolated bacteria were Lacto. plantarum, Lacto delbruekii, Lacto. acidophilus, Lacto. brevis. The isolated bacteria had strong activity against indicator strains. The antibacterial activity was stable at 100°C for 10 min and at 56°C for 30 min, but activity was lost after autoclaving. The maximum production of plantaricin was obtained at 25 - 30°C at pH 6.5. Because, lactobacilli that used to process sausage fermentation are producing antimicrobial activity with heat stability bacteriocin, so, these bacteria may be considered to be a healthy probiotic diet. Lactobacilli originally isolated from meat products are the best condidates as probiotic bacteria to improve the microbiological safety of these foods

Study of nutrition status and urinary tract infection in elderly people at nursing home

Malnutrition is a common problem among nursing home residents and encompasses adverse outcomes. This study was conducted to determine malnutrition and urinary tract infections as well as antibiotic resistance of isolated bacteria at Kahrisak nursing home in Tehran city, capital of Iran. Nutritional status was determined by direct detection of kitchen, checking the menue of weekly foods, quality and quantity of each meal for each person. The mean age of patients in this descriptive study was 77.2 years old, [ranging from 60 to 103]. Samples of midstream urine from these patients were collected and bacteria were identified by st and ard bacteriological methods. Then, antibiotic resistance of bacteria was determined. On the basis of nutritional status, the quality and quantity of food for each meal was good and enough. From 520 samples of urine, bacteria were grown only from 81 samples. E. coli was the most common bacteria and the other bacteria were Proteus, Klebsiella, Staphylococci aureus, Alcaligenes faecalis, Pseudomonas aeruginosa and Providencia. All of bacteria were resistant at different rate to ampicillin, tetracycline, cephalothin and co-trimoxazol, but sensitive to ciprofloxacin and nitrofurantoin. Malnutrition in this study was less than 30%. This may be due to people helping, qualified foods, well nursing and suitable facility at Kahrizak nursing home

survery of food borne bacterial contamination in the hospitals of Iran University of Medical Sciences

Nosocomial infection and its heavy financial cost is a well recognized problem. A variety of sources of organisms involved in nosocomial infection have been identified in recent years. One potential route of bacterial infection is contamination. In order to assess the importance of food contamination, we carried out a survey of bacterial examination of food and the kitchen environment of 14 hospitals. 456 samples were examined. Bacterial growth was observed in 40% and salad yielded the highest frequencies of isolation of bacteria [P<0.001]. Our results strongly suggest that some foods and hospital kitchens are contaminated, and can be sources of endemic infection for hospitalized patients. So we emphasize on increasing awareness, and efforts should be made for improvement of hospital hygiene to control infections