Gut Microbiota and Neuropsychiatric Disorders.

Numerous studies in humans and animals hypothesize that gut microbiota dysbiosis is involved in the development of behavioral and neurological diseases such as depression, autism spectrum disorder, Parkinson disease, multiple sclerosis, stroke and Alzheimer's disease. Some of the most salient works so far regarding the brain-gut axis are mentioned below. The current knowledge on the impact of gut microbiota on nervous system diseases is far from being directly used for pharmacologic or nutritional advice toward restoration of normal bodily functions. It seems that a more comprehensive approach should be followed so that the individual effect of each kind of intervention on the patient's somatic or psychological status is determined. Future research must address global need for regimens which could reestablish normal composition of gut microorganisms after each neuropsychological disorder.

Determination of pilus-islands profile and antibiotic susceptibility of Streptococcus agalactiae isolated from urine of pregnant women.

Background and Objectives: Group B Streptococcus (GBS) is one of the most important causes of neonatal diseases and postpartum fever. GBS infection can be transmitted from the infected mother to her baby during delivery. This bacterium is also involved in causing urinary tract infections and asymptomatic bacteriuria, pyelonephritis, cystitis and urethritis. In addition to capsule, Pilus is known as a virulence factor of GBS. The aim of this study was to evaluate the frequency of pilus islands and antibiotic resistance in GBS isolated from urine of pregnant women in Yazd, Iran. Materials and Methods: In this cross-sectional study, 33 GBS samples isolated from the urine of pregnant women were studied by the multiplex polymerase chain reaction (PCR) method for the presence of pilus islands PI-1, PI-2a and PI-2b. Antibiotic resistance phenotype of tetracycline, penicillin, gentamicin, erythromycin, levofloxacin and clindamycin was determined by disk diffusion method. Data were analyzed using SPSS, version 16. Results: PI-1+PI-2a was the most frequent pilus island in the GBS isolates 28 (84.8%) and the frequency of PI-2b was 5 (15.2%). The frequency of PI-1+PI-2a was 50% in serotype III and 25%, 14.3%, 7.1% and 3.6% in serotypes Ia, II, Ib and V respectively (P=0.492). The sensitivity of all GBS isolates to penicillin was 93.9% and highest resistance to tetracycline (97%), clindamycin (24.2%) and erythromycin (21.2%). Conclusion: Most of the GBS urine isolates examined carried the PI-1+PI-2a gene, which increases bacterial potency in colonization and resistance to the immune system. Penicillin was best choice for prevention.

Effects of chloramphenicol, povidone-iodine 1% and 5% eye drops on the colonisation of conjunctival flora in patients undergoing cataract surgery.

Objectives: the aim was to compare 2 drops of either 5% chloramphenicol, 1% povidone-iodine or 5% povidone-iodine before cataract surgery on reducing the colonisation of bacterial flora in the conjunctiva. Design: This was a double-blind, randomised clinical trial study. Setting: Patients referred to Shahid Sadoughi Hospital in Yazd, Iran, for cataract surgery were studied. Participants: Totally 260 patients were enrolled. Intervention: The affected lower fornix was gently sampled with a sterile swab and cultured on appropriate microbiological media. Then one of the 3 solutions mentioned above was instilled into the conjunctival sac of the cases in groups 1, 2 and 3, respectively. After thirty minutes, new conjunctival swabs were taken and cultured. Main outcome measures: The type of bacteria isolated and their colony-forming unit per mL (CFU/mL) number were primary end-points. The statistical tests of Phi and Cramer's V and Wilcoxon and Kruskal-Wallis were applied to evaluate the relationship between the studied variables and culture results as the secondary end-point. Results: The studied patients were 129 (49.6%) males and 131 (50.4%) females. Bacterial growth was observed in 49 cases (18.85%); the most commonly isolated bacteria were Staphylococcus epidermidis (71.42%). In the povidone-iodine 5% and chloramphenicol groups (but not the povidone-iodine 1%), the decrease in the number of CFU/mL was statistically significant (P = 0.032 and P = 0.005, respectively, Wilcoxon test). Conclusion: A single dose of povidone-iodine 5% and chloramphenicol effectively reduces the colonisation of normal conjunctival bacteria and can be used as effective prophylaxis. Funding: This study was part of an MSc thesis of Nasrin Tofighi. Shahid Sadoughi University of Medical Sciences, Yazd, Iran, funded this work.

The effect of lipopolysaccharide from uropathogenic Escherichia coli on the immune system, testis tissue, and spermatozoa of BALB/c mice.

OBJECTIVE: Uropathogenic Escherichia coli is known to cause urinary tract infections, and the endotoxin (lipopolysaccharide [LPS]) of this bacterium may cause deficiencies of sperm quality and morphology. In the present study, the effects of LPS on mouse sperm were studied, and the levels of interleukin (IL)-17A and possible changes in testis tissue were evaluated. METHODS: LPS of uropathogenic E. coli was extracted using the methanol-chloroform method, followed confirmation using sodium dodecyl sulfate-polyacrylamide electrophoresis. Purified LPS (100 µg/kg) or phosphate-buffered saline was injected intraperitoneally into BALB/c mice for 7 days consecutively in the test and control groups, Mice were sacrificed on days 3, 7, and 42 after the first injection. Blood was tested for levels of IL-17A using the enzyme-linked immunosorbent assay method. Testis tissue and sperm were collected from each mouse and were studied according to standard protocols. RESULTS: The mean sperm count and motility significantly decreased (p=0.03) at 3, 7, and 42 days after the injections. The level of IL-17A in the test groups increased, but not significantly (p=0.8, p=0.11, and p=0.15, respectively). Microscopic studies showed no obvious changes in the morphology of the testis tissue; however, significant changes were observed in the cellular parenchyma on day 42. CONCLUSION: LPS can stimulate the immune system to produce proinflammatory cytokines, resulting in an immune response in the testis and ultimately leading to deficiency in sperm parameters and testis tissue damage. In addition, the presence of LPS could significantly impair sperm parameters, as shown by the finding of decreased motility.

Distribution of Pilus island and antibiotic resistance genes in Streptococcus agalactiae obtained from vagina of pregnant women in Yazd, Iran.

BACKGROUND AND OBJECTIVES: Due to the important role of Streptococcus agalactiae, Group B streptococci (GBS), in production of invasive disease in neonates, investigation regarding the pathogenicity and antibiotic resistance factors is necessary in selecting the appropriate therapeutic agents. Beside capsule, the pilus has been currently recognized as an important factor in enhancing the pathogenicity of GBS. Resistance of GBS to selected antibiotics is noticeably increasing which is mainly due to the anomalous use of these drugs for treatment. The aim of this study was to determine the prevalence of pili genes followed by antibiotic susceptibility of GBS, previously serotyped, isolated from pregnant women in the city of Yazd, Iran. MATERIALS AND METHODS: Fifty seven GBS from pregnant women were subjected to multiplex PCR for determination of PI-1, PI-2a and PI-2b pilus-islands and simultaneously, the phenotype of antibiotic resistance to penicillin, tetracycline, erythromycin, clindamycin, gentamycin and levofloxacin was determined. Antibiotic resistance genes (ermA, ermB, mefA, tetM, int-Tn) were further diagnosed using PCR and multiplex PCR. RESULTS: PI-1+PI-2a with 71.9%; followed by PI-2a (21.1%) and PI-2b (7%) were observed. PI-1+PI-2a in serotype III was (73.2%), serotype II, Ia, Ib and V were 12.2%, 9.8%, 2.4% and 2.4% respectively. GBS penicillin sensitive was 89.5% and 96.5% resistance to tetracycline. The frequency of resistance genes were as follows: tetM (93%), ermA (33.3%), ermB (8.8%), int-Tn (80.7%) and mefA (0). CONCLUSION: Majority of GBS contained PI-1+PI-2a. Hence presence of this pilus stabilizes the colonization, therefore designing a program for diagnosing and treatment of infected pregnant women seems to be necessary.

Molecular Characterization of Streptococcus agalactiae Isolates From Pregnant and Non-Pregnant Women at Yazd University Hospital, Iran.

BACKGROUND: Streptococcus agalactiae (Group B streptococcus, GBS) that colonize the vaginas of pregnant women may occasionally cause neonatal infections. It is one of the most common causes of sepsis and meningitis in neonates and of invasive diseases in pregnant women. It can also cause infectious disease among immunocompromised individuals. The distribution of capsular serotypes and genotypes varies over time and by geographic era. The serotyping and genotyping data of GBS in Iranian pregnant and non-pregnant women seems very limited. OBJECTIVES: The aim of this study was to investigate the GBS molecular capsular serotype and genotype distribution of pregnant and non-pregnant carrier women at Yazd university hospital, in Iran. . PATIENTS AND METHODS: In this cross-sectional study, a total of 100 GBS strains isolated from 237 pregnant and 413 non-pregnant women were investigated for molecular capsular serotypes and surface protein genes using the multiplex PCR assay. The Chi-square method was used for statistical analysis. RESULTS: Out of 650 samples, 100 (15.4%) were identified as GBS, with a predominance of capsular serotypes III (50%) [III-1 (49), III-3 (1)], followed by II (25%), Ia (12%), V (11%), and Ib (2%), which was similar with another study conducted in Tehran, Iran, but they had no serotype Ia in their report. The surface protein antigen genes distribution was rib (53%), epsilon (38%), alp2/3 (6%), and alpha-c (3%). CONCLUSIONS: The determination of serotype and surface proteins of GBS strains distribution would be relevant for the future possible formulation of a GBS vaccine.

Comparison of PCR, Wright agglutination test and blood culture for diagnosis of brucellosis in suspected patients.

Brucellosis has long been prevalent in Iran, with considerable medical and economic importance. Timely diagnosis is needed for early management and effective prevention of its consequences in human beings and animals. Current diagnostic methods impose peculiar challenges in terms of analytical method performance. This study compares diagnostic sensitivity, specificity, predictive Value of Positive (PVP) and Predictive Value of Negative (PVN) for Polymerase Chain Reaction (PCR), Wright agglutination test and blood culture used for patients suspected of brucellosis. In 120 patients clinically suspected of brucellosis and referred by physicians to the Yazd central Medical Laboratory, some relevant demographic, occupational, nutritional and clinical data were collected. Also, venous blood samples were drawn for diagnosis of brucellosis using PCR, Wright agglutination test and blood culture techniques. The most frequent symptom of patients was arthralgia (82 cases, 68.3%). PCR was positive in 25 cases (20.8%), wright test in 21 patients (17.5%) and blood culture in 6 cases (5%). In 20 out of 21 wright-positive cases, PCR was positive and all of the culture-positive patients had positive PCR. Sensitivity, specificity, PVP and PVN of blood culture compared to PCR (as the gold standard test) were 24, 100, 100 and 86%, respectively, but the above parameters when PCR is compared with blood culture (as gold standard) were 100, 83, 24 and 95%, respectively. PCR has better analytical performances than blood culture for diagnosis of brucellosis and is suitable for confirmation of Wright-positive cases.