Dysbiosis of fecal microbiota and high frequency of citrobacter, klebsiella spp., and actinomycetes in patients with irritable bowel syndrome and gastroenteritis

Aim: This study was aimed to characterize putative differences of fecal microbiota between irritable bowel syndrome[IBS] and gastroenteritis patients and healthy controls

Background: New evidence proposed that gut microbiota has a deep effect on the balance between health and disease

Patients and methods: The presence of Clostridium difficile, Campylobacter spp., Enterobacteriacea and Staphylococci weredetected in the samples using selective and specific culture media. Microscopic examination of the samples was done to detectActinomycetes, yeasts, Bifidobacteria, Fusobacterium spp., as well as white blood cells, red blood cells, mucus and epithelial cells

Results: Results of this study showed relatively higher frequency of Citrobacter spp., Lactobacilli, and Actinomycetes in theIBS patients. Elevated levels of WBC, RBC secretion, and increased amounts of Klebsiella, Escherichia coli and Citrobacterspp. were characterized in the patients with gastroenteritis compared with the control group

Conclusion: Depletion of gram positive cocci and gram negative bacilli also suggested dysbiosis of intestinal microbiotain these patients

Genetic profile variation in vaccine strains and clinical isolates of bordetella pertussis recovered from Iranian patients

Re-emergence of pertussis has been reported in Iran despite a high rate of vaccination coverage. Low efficacy of the vaccine might be due to the genetic divergence between Clinical versus vaccine strains. In the current study, the genetic profiles of Clinical isolates and vaccine strains of Bordetella pertussis [B. pertussis] were assessed by using Pulsed Field Gel Electrophoresis [PFGE]. Following phenotypic and molecular identification of isolates, XbaIdigested genomic DNA of 5 Clinical isolates, 2 vaccine strains and a Tohama I strain were analyzed by PFGE along with B. parapertussis as a control. Seven distinct PFGE profiles were found among all examined isolates/strains. In 5 Clinical isolates, 4 profiles were identified whereas the vaccine strains displayed 2 distinct profiles. The reference strain, Tohama I had a distinct profile. Vaccine and Clinical profiles had low similarity, with relatedness of approximately 40%. The genetic profiles of B. pertussis were different between circulating isolates and vaccine strains used in the national vaccination programs. Since new genetic profiles of B. pertussis can be disseminated periodically, the profiles of isolates circulating in the population should be monitored over the course of the re-emergence

[Isolation and identification of Nocardia asteroids complex isolated from thigh abscess in a patient with Behcet's syndrome: the first report from Iran]

Nocardia species are Gram-positive, partially acid fast, non-motile, cata-lase positive, aerobic and saprophytic actinomycetes found all around the world. They invade the human body from the environment via trauma and respiratory tract and cause cutaneous, pulmonary and systemic diseases. They are able to grow in various media.The organisms opportunistically infect both immunocompromised and immuno-competent individuals. Behcet's disease is an autoimmune disease and immunocompromised patient which may suitable host for Nocardia bacterium. The present study is the first case report of isolation of Nocardia from the thigh abscess in a patient with behcet's disease from Iran. A 39-year-old man with Behcet's disease in August 2011 was admitted to Shariati hospital Tehran, with swelling and pain in the left flank and left thigh. Microscopic identification from direct microbiological slide of thigh abscess discharge demonstrated number of lymphocytes, neutrophils and macrophages foamy and white blood cells together with filamentous bacteria. Further microbiological characterization using phenotypic and antibiogram tests with disk diffusion method, demonstrated that the isolated bacterium is Nocardia asteroides complex. The bacteria were sensitive to ampicillin, vancomycin, ceftriaxone, amikacin and cotrimoxazole but it was resistant to clindamycin, erythromycin, penicillin G, cephalothin and gentamicin. The patient was treated with cotrimoxazole. Because of the high incidence and high mortality of Nocardia infection in immunocompromised cases, rapid detection and timely treatment for these patients is necessary

[Prevalence of periodontopathogenic bacteria in patients suffering from periodontitis using culture and PCR methods]

Periodontitis is one of the most common oral diseases with the various incidence rates in different populations. A number of bacteria are considered as the major etiologic agents of periodontitis. The aim of the present study was to determine the prevalence of periodontopathogen bacteria in patients using both PCR and culture techniques. In this study, one hundred patients [including 62 females and 38 males with an average age of 49 +/- 11.5 years] with adult periodontitis referred to periodontics department of School of Dentistry/Tehran University of Medical Sciences were investigated. The samples were taken and sent immediately to the laboratory for culture and molecular evaluation. The PCR was performed using specific primers and the statistical analysis of data was performed using SPSS statistic software and McNemar test. The results demonstrated that the total detection rate in culture method was 64%. The rate of Aggregatibacter actinomycetemcomitans [Aa] was 28% which was significantly higher than that of Porphyromonas gingivalis [Pg] [6%] and Prevotella intermedia [Pi] [3%]. 27% of cases showed mixed bacterial growth. 65% of patients were positive using molecular method. The rate of Aa [30%] was significantly higher than that of Pg [7%] and Pi [5%]. The mixed PCR positive rate containing of Aa, Pg and Pi was [23%].In this study, it was found that most of the bacteria isolated using culture and molecular methods were Aa, Pg and Pi, respectively. Although the detection frequencies of both techniques were similar, the specificity, sensitivity and bacterial detection speed of the PCR technique is obviously higher. Therefore, the use of molecular techniques is strongly recommended. However, both techniques seem to be suitable for microbiological diagnostics.

Molecular typing of nocardia species

Identification of clinically significant Nocardia species is essential for the definitive diagnosis, predict antimicrobial susceptibility, epidemiological purposes, and for an effective treatment. Conventional identification of Nocardia species in routine medical laboratories which is based on phenotypic [cellular morphology, colonial characteristics], biochemical and enzymatic profiles, and chemotaxonomic characteristics is often laborious, and timeconsuming. The procedure requires expertise, and newer species can be difficult to differentiate with accuracy from other related species. Alternative methods of identification, such as high performance liquid chromatography [HPLC] and molecular biology techniques allow a better characterization of species. The taxonomy of the genus Nocardia has been dramatically been revised during the last decade and more than 30 valid human clinical significance species of Nocardia have been reported. The use of molecular approaches, including 16S rRNA gene sequencing, restriction fragment length polymorphism [RFLP] or PCR restriction endonuclease analysis has been the focus of recent investigations to distinguish the isolates of Nocardia from other actinomycetes genera. The methods have revolutionized the characterization of the Nocardiae by providing rapid, sensitive, and accurate identification procedures. The present review describes the currently known medically important pathogenic species of Nocardia.

[ identification of nocardia in BAL specimens of bronchoscopic patients by using classical and molecular methods]

Nocardiosis is a rare and potentially life-threatening infection caused by several species of the Nocardia genus. The objective of this study was to develop and evaluate a rapid and new method to clinically identify relevant Nocardia species. Rapid and accurate diagnosis of Nocardia species is essential for the treatment of severe infections and prevention of cerebral abscess. One hundred and eighty patients, 103 [57.22%] male and 77 [42.78%] female, with severe symptomatic pulmonary infection were studied in the course of a 12-month period in Dr. Shariati Teaching Hospital affiliated to Tehran University of Medical Sciences in 2010. The specimens were cultured and identified using microbiological and biochemical tests. Polymerase chain reaction [PCR] was used to directly identify the organism in the broncoalveolar lavage samples collected from the patients. NG1 and NG2 primers were used to amplify a Nocardia genus-specific 598-bp fragment of 16S rRNA. Nineteen samples [10.56%] were positive with PCR and 5 samples [2.78%] with conventional methods. All samples with positive cultures were also positive by PCR. The results of this study showed that PCR has a high sensitivity and accuracy for the detection of Nocardia compared with culture and biochemical tests. Considering the rapidity, precision, high sensitivity and specificity of molecular techniques, use of these techniques is suggested in conjunction with conventional methods for the detection of Nocardia phenotypes in clinical laboratories and research centers

Molecular analysis of van HAX element in vancomycin resistant enterococci isolated from hospitalized patients in Tehran

Vancomycin [glycopeptide]-resistant enterococci [VRE or GRE] can cause serious problems for hospitalized patients due to the limited options for treatment of VRE infections. As infection with VRE increases in hospitals, further knowledge about vancomycin resistant genes is needed. Isolates of Enterococcus spp. were collected from hospitalized patients in Tehran [Iran] during 2006. Detailed molecular analysis was performed for vancomycin resistance genotype and vanHAX using conventional PCR and PCR- RFLP [restriction fragment length polymorphism], respectively. out of 830 enterococci spp., 48 VRE isolates [5.8%] were obtained. All of VRE isolates carried vanA gene. DdeI digestion of vanHAX element showed the presence of point mutation at 8234 position. This study indicates that vanA is a predominant genotype in Iranian isolates. In addition, PCR-RFLP analysis revealed the presence of two types of vanHAX element in vanA harboring transposons

Evaluation of inhibitory effects of Iranian propolis against filamentous bacteria

To investigate the antibacterial activities of propolis in samples collected from Zanjan province IRAN, against 25 pathogenic strains of bacteria. In order to evaluate the biological properties of methanol extract of propolis using agar distribution methods [disk and drop plate]. Seven concentrations of methanolic extract of propolis were prepared and added drop wise to the bacterial seed layer cultured agar media individually. The diameter of the clear zone formed in each concentration was measured and correlated to the ability of the extracts to inhibit the growth of bacteria. Nocardia asteroides and N. brasiliensis has nearly shown the same susceptibility to various concentrations of propolis extract, and the complete clear zones revealed that this effect was quite remarkable. For other bacteria, different degrees of susceptibility to propolis were observed. We came to this conclusion that zones formed by 50mg/ml Amikacin in agar was similar to that of 5% concentration of propolis, and that the potency of propolis is 80% of Amikacin potency, which is the most effective antibiotic against Nocardia

Therapeutic effect of sodium alginate in experimental chronic ulcerative colitis

The aim of this study was to test the therapeutic efficacy of sodium alginate in a rat model of trinitrobenzene sulfonic acid [TNBS]-induced inflammatory bowel disease. This experiment was carried out using 77 Sprague-Dawley rats which were divided into six groups; normal, control, prophylactic, therapeutic and two experimental groups. Rats were sacrificed 1, 2, 3 and 6 weeks after colitis induction. Severity of colitis was graded macroscopically and assessed using serum and colonic mucosal cytokines and eicosanoids. Intrarectal TNBS [30 mg] produced a significant chronic ulcerative colitis. The lesions were most severe on day seven after TNBS instillation, and then declined, but lesions were still observed after six weeks. TNBS administration also significantly enhanced the serum and colonic mucosal cytokines [TNF-alpha and IL-6] and eicosanoids [LTB4 and PGE2] levels, which paralleled with the severity of colitis. Low viscosity sodium alginate [LVA] solution as therapeutic agent was administered orally as drinking water at concentration of 0.5% [W/V] for six weeks. Results showed that pre-treatment [in prophylactic group] and treatment with LVA were significantly able to reduce colonic damage score, serum level and colonic mucosal production of TNF-alpha, IL-6, LTB4 and PGE2 in pre-treated and treated animals compared with non-treated controls. LVA therapy is able to suppress chronic ulcerative colitis in experimental model

Oral actinomyces strain isolates in patients suffering from progressive periodontitis and dentoalveolar abscess

The purpose of this study was to isolate and characterize of the Gram-positive anaerobic pleomorphic bacilli in particular Actinomyces strains from subgingival plaque and periapical abscesses specimens. One hundred twenty six subgingival plaque samples from 100 patients with progressive periodontitis and 45 pus samples from 32 patients with dentoalveolar abscesses were included in this study. Sample collection criteria were contained deep pocket [over 3 mm], no recent antibacterial therapy and lack of systemic infection. The paper points specimens collected were transferred and cultured using appropriate media. The only strain of A. viscosus was obtained from a patient with progressive periodontitis with pocket depth of 6 mm and two strains of A. naeslundii with pocket depth of 4 mm. The peak incidence number of progressive periodontitis [35%] was in the third decade [31-40] and the lowest incidence [10%] was in the first decade [<20]. Forty patients complained of bleeding of teeth and gingival disease with the lower incidence of [42.5%] in female. Of the 32 patients with dentoalveolar abscesses, the peak incidence of the dentoalveolar abscesses [25%] was seen in the group aged 31-35, while the low incidence [6.3%] was in the group aged 16-20 years. The causes of the progression of dentoalveolar abscesses were found as nineteen patients [59.4%] with dental carries, seven patients [21.9%] with a dental extraction and six patients [18.8%] with uncompleted endodontics treatment. The present research indicates that most patients have neglected dental care and poor oral hygiene, suffer from the gingival disease and bleeding gum. The Columbia blood-agar with 10 micro L/mL cephadroxyl is recommended for the isolation of Actinomyces species, at; 37 for 5-7 days in anaerobic conditions. To obtain a higher recovery of these microorganisms, the Columbia blood-agar without antibiotic, in candle jars is recommended

Antibacterial effect of glycyrrhetinic acid on 55 hospital strains of staphylococcus aureus and 32 actinobacillus actinomycetemcomitans.

Glycyrrhetinic acid is a major component of a traditional plant called Licorice. This substance has been found to have some pharmacological properties including anti-inflammatory, anti-viral, anti-bacterial, anti-fungal, anti-allergic, anti-carcinogenic and anti-peptic-ulcer. Glycyrrhetinic acid also affects against some parasites such as Trichomonas vaginalis. In this study, 55 hospital strains of Staphylococcus aureus and 32 Actinobacillus actinomycetemcomitans, were isolated from patient's specimens by culture method. Antibacterial activities of glycyrrhetinic acid against those microorganisms were investigated by determining minimum inhibitory concentration [MIC] and minimum bactericidal concentration [MBC] methods. The MIC for S. aureus and A. actinomycetemcomitans were 64 and 8 micro g/ml respectively. The MBC for S. aureus and A. actinomycetemcomitans were 64 and 16 micro g/ml respectively. It is concluded that Glycyrrhetinic acid is effective against Staphylococcus aureus and Actinobacillus actinomycetemcomitans in appropriate concentrations