Dr. Mohammad Reza Pourshafie
Vol 9 No 1-2 (2020)
Background: Chlamydia abortus, is one of the most important causes of abortion in small ruminants. Evaluating the frequency of chlamydial infection in abortion of animals is beneficial in epidemiological surveys. The purpose of the present study is to determine the frequency of abortion caused by Chlamydia abortus using PCR method. Methods: A total of 200 fetuses were collected from 150 ewes and 50 does. The samples were collected from abomasal contents and lungs of the fetuses and using PMP gene of Chlamydia abortus, PCR was conducted. The infection occurrence with regard to the species of animals, age, gender and type of pregnancy along with age, numbers of pregnancy and numbers of abortion in the aborted animals were statistically analyzed by Chi-squared test, t-test and Spearman correlation coefficient which all were calculated using SPSS version 25. Results: The bacterium DNA was detected in 47 fetuses. The infection occurrence didn’t have significant statistical relationships with the species, age and gender of the fetuses. Chlamydial infection in the twin fetuses was significantly more than the single ones. The infection had statistical relationship with ages and parturition numbers of the aborted animals but not with the numbers of abortion. Conclusion: Regarding the high frequency of abortion caused by Chlamydia abortus in this study (23.5%), it is necessary to boost the information about the prevalence of Chlamydia abortus in different regions of our country.
Background: Staphylococcus aureus is the most important etiological agent of bioﬁlm associated-infections. It is one of the Gram-positive pathogens causing a wide range of nosocomial infections. Genes involved in biofilm formation is a defensive mechanism of this pathogen to combat the host immune response and remain stable in hostile environment. The aim of this study was to investigate prevalence of biofilm associated genes (BAGs). Methods: Eighty samples of Staphylococcus aureus isolates from human infections were collected. Thirteen BAGs including rbf, sigB, sasG, icaA, sarA, icaR, icaD, clfA, clfB, fib, fnbpB, bap and fnbpA were amplified by PCR assay. Results: The prevalence of genes were as follows: sigB (93.7%) and sarA (90%) were the most prevalent BAGs followed by rbf (83.7%), fib (80%), sasG (78.7%), icaR (78.7%), clfB (78.7%), clfA (78.7%), fnbpA (73.7%), icaD (66.2%), icaA (50%), fnbpB (22.5%). However, bap was not detected in any isolate. Conclusion: This study showed that the sensitivity and specificity of PCR is high in the identification of biofilm associated genes in S. aureus. However, researchers need new molecular methods to improve understanding of the exact role of the genes involved in biofilm formation.
Bifidobacterium bifidum does not show cell toxicity on leukemic cells of AML patients but induced cell death on K562 cell lineBackground: Leukemia is a kind of blood cancer diseases which are generally known as neoplasm. There are two types of blood cancer called acute myeloid leukemia (AML) and chronic myeloid leukemia (CML). This type of leukemia targets plasma cells and prevents the production of antibodies in the body and makes the immune system vulnerable to infections. Methods: Blood samples from 10 people with AML and 10 normal individuals were collected who were defined as the case and control groups, respectively. PBMCs were isolated by Ficoll hypaque and cultured in order to the MTT assay. Then, the cell wall of Bifidobacterium bifidum bacterium was treated in five concentrations on these cells and the MTT test was performed at 24, 48 and 72hrs. Also, K562 leukemia cell was cultured then after; the MTT test was performed in the same protocol. The expression of BAX, Bcl2, β-actin genes were assessed by real-time PCR after 48 and 72hrs of treatment. Results: The results of MTT test could not show any significant differences in extracted PBMCs from individuals as compared to control group. But, K562 cell line in treatment with the cell wall of Bifidobacterium bifidum showed a significant cell toxicity effect at 48 and 72hrs versus non-treated K562 cells. BAX gene expression was significantly increased versus β-actin gene control only on K562 cell line, but not on AML derived leukemic cells. Conclusion: According to the obtained results, Bifidobacterium bifidum, as a probiotic bacterial species, can impact the growth and/or proliferation of cancer cells; however, it could depend on the type of cancer cells.
The Study of Antimicrobial Resistance among Salmonella enterica Strains Isolated from Children with Gastroenteritisin in Tehran, IranBackground: Salmonella enterica is one of the predominant causes of the food-borne salmonellosis in humans. The aim of this study was to determine antimicrobial resistance patterns of Salmonella enterica isolated from stool samples of children with gastroenteritisin in Tehran, Iran. Methods: Stool samples of patients with diarrhea in a pediatric hospital in were collected from June 2017 to May 2018. Microbiological methods were used for identification of Salmonella. The identity of Salmonella enterica serotype enteritidis (S. enteritidis) was also confirmed by a multiplex-PCR. Antibiotic susceptibility testing was performed according to the standard procedure of the Clinical and Laboratory Standards Institute (CLSI). Results: Of 800 samples, 24 were identified as Salmonella. The most prevalent serotype was S. enteritidis (n=10, 41.7%), followed by S. paratyphi C, (n=6, 25%), S. paratyphi B (n=4, 16.7%), S. arizonae 2 (n=2, 8.3%), and S. paratyphi A (n=2, 8.3%). The highest rates of antibiotic resistance were obtained for nitrofurantoin (100%), followed by nalidixic acid (45.8%), and tetracycline (16.7%). Of 24 S. enteritidis, 9 distinct antibiotypes (Abs) were observed. In this respect, 3 isolates (12.5%) were resistant to at least three or more antibiotics. The most prevalent antibiotype was AB1 (n=8, 33%), which was indicative of resistance to nitrofurantoin. Conclusion: Considering the constant changes in antibiotic resistance patterns among food-borne pathogens over time, continuous monitoring of multidrug-resistant Salmonella isolates would definitely improve infection control strategies.