Atypical Yersinia virulence markers isolated from children with diarrhea

Background and Objective: Yersinia is a gram-negative bacillus that cause diarrhea through consumption of contaminated food and water. This study was performed to identify the atypical Yersinia virulence markers isolated from children with diarrhea

Methods: This descriptive cross -sectional study was done on 384 fecal samples of 0- 14 years old children admitted at children medical center from August 2011 to August of 2012. Fecal samples, for the enrichment, after 21 days of incubation in alkaline buffer with pH=7.2 at 4degree C, on days 7,14 and 21 samples were cultured on CIN agar and Mac agar and then confirm the differentiation atypical Yersinia from other typical Yersinia species from fermentation of different sugars. Isolates were tested for marker of virulence including calcium dependence, auto agglutination, Congo red uptake and binding of crystal violet

Results: Out of 384 stool samples, 4 [1.04%] were infected with Yersinia [Yersinia frederikseni, Yersinia kristensenii and Yersinia enterocolitica]

Out of these three, only two samples in association was positive with virulence markers

Conclusion: Phenotypic markers can be used to study the properties of phenotypic strains of Yersinia

[Evaluation of antibacterial properties of human amniotic membrane in vitro]

Amniotic membrane is the inner-most layer of the three fetal membranes. The membrane is consisted of three layers; epithelial layer, basal membrane, and connective tissue. Owing to expression of mRNA of elafin, HBD 1-3, and secretory leukocyte protease inhibitors, amniotic membrane has antimicrobial properties. The aim of the current study was to evaluate the in vitro antibacterial effect of human amniotic membrane on standard bacterial species of Salmonella enterica BAA-708, E.coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 7881, and Enterococcus faecalis ATCC 29212. Fresh amniotic membranes were obtained from Organ Transplant Bank of Imam Khomeini Hospital in Tehran. The membranes were obtained from pregnant women who had negative tests for HIV, HBV, HCV, and syphilis after elective Cesarian section. The membranes were cut into 1.5× 1.5 cm pieces under sterile conditions. The membrane pieces were placed on Müller-Hinton agar medium containing the bacterial suspensions and then incubated at 37 [degree sign]C for 24 hours. The antibacterial properties of amniotic membrane against Salmonella enterica and E. coli were demonstrated by development of the no growth halo, but for Pseudomonas aeruginosa only a very narrow halo was observed. The halo was not developed for Klebsiella pneumoniae and Enterococcus faecalis. Amniotic membrane showed antibacterial effects against a wide spectrum of bacteria. With regard to the increasing antibiotic resistance, use of amniotic membrane against pathogenic bacteria can be considered valuable

Evaluation of culture and pcr methods for diagnosis of group b streptococcus carriage in Iranian pregnant women

Group B streptococcus [GBS] is one of the most important cause of morbidity and mortality among newborns especially in developing countries. It has been shown that the screening approach rather than the identification of maternal clinical risk factors for early-onset neonatal GBS disease is more effective in preventing early-onset GBS neonatal disease. The objective of this study was to detect GBS among clinical samples of women using PCR and standard microbiological culture. Samples were taken from 375 women at 28-38 weeks of gestation during six month from January 15 till June 15, 2011 from a hospital in Tehran, Iran. Samples were tested by standard culture using Todd- Hewitt broth, blood agar and by PCR targeting the cfb gene. Among the 375 women, 35 [9.3%] were identified as carriers of group B streptococci on the basis of the results of the cultures of specimens, compared to 42 [11.2%] on the basis of PCR assay. We found that GBS can be detected rapidly and reliably by a PCR assay in vaginal secretions from women at the time of delivery. This study also showed that the rate of incidence of GBS is high in Iranian women

frequency of extended spectrum beta lactamase and CTX M-I of Escherichia coli isolated from the urine tract infection of patients by phenotypic and PCR methods in the city of Khoy in Iran

The production of Extended Spectrum Beta Lactamases [ESBLs] by Escherichia coli is the main cause of resistance to Cephalosporins. In the past decade, CTX-M enzymes have become the most prevalent ESBLs in Europe, Canada, and Asia. In this study, the frequency of ESBL- producing E.coli and molecular detection of the CTX-M-I group was investigated. A total of 400 urine samples were collected from both hospitalized and out-patients in Khoy's hospitals between November 2009 and April 2010. Out of these samples, 188 were identified as E.coli by standard biochemical tests. The antibiotic Susceptibility tests to 10 antibiotics were performed by the-disk-agar diffusion [DAD] method. ESBL production was screened by phenotypic test that including disk diffusion agar and combined disk as recommended by the Clinical and Laboratory Standards Institute [CLSI] Screened isolates were investigated by PCR assay for detection of CTX-M-I group genes. The results show that out of 188 E.coli isolates identified, 56 [29.8%] were producing ESBls by phenotypic test. All isolates were sensitive to imipenem. Overall, 49 [87.5%] isolates were confirmed as CTX-M-I producer by PCR. The results of this study showed that about 30% of the identified E.coli were producing ESBL Therefore, we recommend to use molecular methods in such researches

[Synergistic effect polymyxin B sulphate and trimethoprim on yersinia enterocolotica and closely related species]

Previous studies have shown that polymyxin B sulfate and trimthoprim antibiotics are not individually effective on Yersinia enterocolitica and their closely related species. The aim of this study was to evaluate the synergistic effect of above antibiotics on Y. enterocolitica and their closely related species, from the clinical and the natural environment specimen collected in Iran, and compare them with the isolates that that were obtained from the Pasteur institute collection in France. In total, 73 species from Iran and 25 from the Pasteur institute in France were tested. The microdilution method was used for the MIC according to the standard protocol. The synergistic effect was seen in all tested samples. However, the human species from the Pasteur institute were more sensitive than the Iranian human and the environmental species were less sensitive than clinical specimens [1.6+16 micro gr, 0.4+4 micro gr in French Samples]. The Y. enterocolitica isolates were less sensitive than the related species such as Y. intermedia, Y. fredriksenii, and Y. kristensenii. The synergistic effect polymyxin B sulfate and trimthoprim were more evident on other closely related Yersinia species Y. enterocolitica

[Autologous transplantation of peripheral blood mononuclear stem cells in patients with buerger's disease following stem cell mobilization with granulocyte-colony stimulating factor: a report of three cases]

Treatment with autologous peripheral blood mononuclear stem cells [PB-MNCs] has shown benefits in patients with Buerger's disease. The purpose of this study was to evaluate the feasibility, safety and efficacy of PB-MNCs transplantation in patients with Buerger's disease. Three patients were treated by PB-MNCs transplantation. The patients received G-CSF at a dose of 5 ug/kg/day prior to the treatment. Stem cells were harvested from peripheral blood and injected directly into the muscle of the affected limbs. Patients reported pain relief after approximately one month. Venous oxygen saturation in the affected lower limb increased and clinical symptoms showed improvement. Angiographic scores were significantly improved in the transplanted patients. Satisfactory clinical improvements were observed by injecting PB-MNCs after G-CSF mobilization, suggesting that this novel cell therapy method is feasible, safe and efficient. No adverse effects were observed following the intramuscular administration of stem cells

Evaluation of PCR method for diagnosis of Group B Streptococcus carriage in pregnant women

Group B Streptococcus [GBS] [Streptococcus agalactiae] is the leading cause of morbidity and mortality of newborn infants and accounted as a leading factor causing septicemia after birth in mothers. Infections in infants are usually acquired by contact with the genital tract of the mothers during labor and delivery. In two last decades, significant progress toward detection, prevention and treatment of pregnant women carrying GBS has been achieved. A rapid screening test for GBS that could accurately identify pregnant women carrying the bacteria at the time of delivery would obviate the need for prenatal screening. The standard method for the diagnosis of GBS colonization consists of culturing vaginal and anal secretions in a selective broth medium which inhibits the growth of other microorganisms. Today, it is accepted that PCR has a high sensitivity and specifically in diagnosis. The goal of this study was to screen pregnant woman carrying GBS by PCR. Samples were taken from anal and vaginal mucus of 125 pregnant women who were at 28-38 weeks of ingestion by swab. Samples were tested by standard culture using Todd Hewitt Broth and Blood Agar and also by PCR using primers specific for cfb gene. Culture identified 10 [8%] women as carriage of GBS out of 125 women tested. On the other hand, the PCR assay could identify 12 [9/6%] women positive for GBS. In comparison to culture results, sensitivity, NPV, specificity, and PPV of PCR were 100%, 100%, 98%, and 83%, respectively. The time required for PCR assay and culture were 2h and 36h, respectively. We found that GBS can be detected rapidly and reliably by a PCR assay using combined vaginal and anal secretions from pregnant women at the time of delivery. Also this study shows that the rate of incidence of GBS is high in Iranian pregnant women. We, therefore, recommend screening of pregnant women for detecting of GBS emphatically

[Comparison of the prevalence of microbial contamination in packed and unpacked redmeat and chicken mea tat retail outlets and department stores in southern Tehran]

Despite advances in disease prevention and food materials technology, food borne diseases are still a major problem in both developed and developing countries. Moreover, meat plays a key role in transfer of bacteria, especially "Zoonotic" to humans. Therefore, we decided to investigate the outbreak of pathogenic bacteria such as Salmonella,Campylobacter. Yersinia and Aeromonas in red meat and chicken offered as packed and unpacked in areas under the authority of Tehran university of medical sciences 630 samples including 315 raw chicken meat and 315 raw red meat samples were collected and tested for a period of one year from July, 2004 to August.2005. Samples were collected from shops selling packed meat and chicken as well as shops selling unpacked meat and chicken in different parts of the south of Tehran The methods used for the laboratory investigation were based on Iranian National Standard Procedure No. 2394. Of the 630 samples of chicken and meat, 183 samples [29%] were contaminated. 49.2 percent of the contaminated samples were chicken meat and 8.9 percent were red meat. From the total, 71 samples were contaminated with salmonella [11.3%], 68 samples with Campylobacter [10.8%], 26 samples with Yersinia entrocolitica [4.1%] and 18 samples with Aeromonas [2.9%]. In red meat samples, microbial contamination was observed in 4.9% of packed and 10.3 percent of unpacked samples. Contamination rate of chicken samples was higher including 59.3% of packed and 45.7% of unpacked chicken samples. The observed difference between the remitting samples of packed and unpacked chicken was statistically significant. [P< 0.05] Our results indicated that although the centers selling packed and unpacked red meat from south of Teheran showed different microbial contamination rate, the differences were statistically insignificant. [P> 0.05]

[Prevalence of Yersinia spp. in meat and chicken marketed in southern Tehran]

Yersinia is an important water- and food-borne bacterium causing gastroenteritis in humans. From December 2002 to July 2003, a total of 250 samples -including 158 meat samples and 92 chicken samples- were taken from butcheries and poultry shops operating under the supervision of Tehran University of Medical Sciences. We used a two-step enrichment procedure: phosphate buffer saline was used as primary enrichment within 3 weeks in refrigerator [cold enrichment]. Then we applied KOH treatment as secondary enrichment and performed cultures on CIN agar. In this study, 44.4% of all samples showed Yersinia contamination. The prevalence of Yersinia was 29.1% in meat and 70.7% in poultry. Of the 155 Yersinia isolates, 53 [34.2%] were identified as Y. enterocolitica, 47[30.3%] as Y. intermedia, 42 [27%] as Y. fredriksenii and one [0,6%] as Y. kristensenii. Biotyping of Y. enterocolitica showed that 51 strains [39.7%] corresponded to biotype 1A, 13 strains [24.6%] to biotype 1B, one [1.8%] to biotype 2, three [5,7%] to biotype 3 and one [1.8%] to biotype 4. Fourteen strains [26.4%] could not be classified. The high prevalence rates in meat and poultry implies that these products could be widely contaminated with Yersinia, thus serving as important vehicles for transmission to humans