Genetic Characterization of Campylobacter Jejuni and C. coli Isolated From Broilers Using flaA PCR-Restriction Fragment Length Polymorphism Method in Shiraz, Southern Iran

Virulence Factors as Promoters of Chronic Vulvovaginal Candidosis: A Review

INTRODUCTION

The vast majority of the species of the genus Candida spp. is commensal in humans; however, some are opportunistic pathogens that can cause infection, called candidosis. Among the different types of candidosis, we highlight the vulvovaginal (VVC) which can occur in two main clinical variants: chronic (cVVC) and episodic or sporadic. The incidence of cVVC has been worrying the scientific community, promoting the research on genotypic and phenotypic causes of its occurrence. We summarize important findings on factors that favor chronic vulvovaginal candidosis with respect to molecular epidemiology and the expression of various virulence factors, while clarifying the terminology involving these infections.

AIM AND METHODOLOGY

The aim of this review was to gather research that linked virulence factors to VVC and its persistence and recurrence, using two databases (Pubmed and Google Scholar). Predisposing factors in women for the occurrence of cVVC and some studies that refer new preventive and alternative therapies were also included, where appropriate.

RESULTS AND DISCUSSION

Several studies have been shedding light on the increasing number of persistence and recurrences of VVC. The expression of virulence factors has been related to both chronic forms of VVC and antifungal resistance. Other studies report mutations occurring in the genome of Candida spp. during the infection phase which may be important indications for new therapies. The introduction of preventive therapies and new therapies has revealed great importance and is also highlighted here.

in a Greek Poultry Slaughterhouse

Campylobacter species are one of the leading causes of foodborne disease. Poultry is a major reservoir and source of its transmission to humans. The aim of this study was to estimate the prevalence and antimicrobial resistance of Campylobacter spp. isolated from chicken carcasses, the environment, and processing equipment of a poultry slaughterhouse in Greece, to identify the dominant Campylobacter species and to determine if there are clonal relationships among the isolates. Fifty poultry samples and 25 environmental samples were examined using microbial cultures and PCR. Forty-nine of 50 poultry samples (98%) were found to be positive for Campylobacter spp. The environment of the slaughterhouse was also found to be significantly contaminated with Campylobacter spp. Thirty-seven isolates were found to be susceptible to all antimicrobials tested (56.1%) and 29 isolates showed resistance to at least two of the antimicrobials tested (43.9%). We observed 24 different PFGE-types among the 53 isolates with 14 of them isolated only once, while five PFGE-types were represented by two isolates. The remaining 29 isolates were represented by five PFGE-types each consisting of three to 12 isolates. Regarding the relationship of the PFGE types and corresponding resistance profiles, all strains of each PFGE-type shared the same antimicrobial resistance profile. This study reports evidence for Campylobacter spp. cross-contamination among broiler carcasses in a Greek slaughterhouse.

Typing of Campylobacter jejuni isolated from poultry on the basis of flaA-RFLP by various restriction enzymes

RFLP analysis of the flagellin (flaA) gene was compared using three different restriction endonucleases i.e DdeI, HinfI and DpnII to determine the genetic diversity among 43 Campylobacter jejuni isolates of poultry origin from the same geographical area. flaA gene was amplified in all the isolates and RFLP analysis showed variations. Dde-based RFLP was found most efficient in discriminating C. jejuni isolates by generating 15 different Dde-RFLP patterns with discriminatory index (D.I) of 0.9258 whereas DpnII produced seven Dpn-RFLP patterns (D.I .= 0.8427). While HinfI enzyme produced only six Hinf-RFLP patterns (D.I .= 0.6977). The discrimination of Dpn-RFLP was comparable to discrimination given by Dde-RFLP analysis, which is generally used to study flaA gene RFLP.

PCR-RFLP Provides Discrimination for Total flaA Sequence Analysis in Clinical Campylobacter jejuni Isolates

The aims of this study were to determine the genetic relatedness among 20 clinical Campylobacter jejuni samples isolated from children with diarrhea in Iran and to introduce the best method of discrimination based on flagellin gene (flaA) sequence divergence. A total of 400 stool specimens were obtained from children under 5 years of age from July 2012 to June 2013. Primers were designed based on conserved sequences flanking the flaA gene that encompassed and amplified the entire flaA gene and followed by sequencing and data analysis with MEGA version 6.0.6 software. Ninety amino acids and 560 nucleotide polymorphic sequences were detected within 1,681 bp of the flaA sequence of which 43 (2.5%) and 12 (0.7%) were singletons, respectively. New repeat boxes within the flaA sequences were found in this study. Unweighted Pair Group Method with Arithmetic Mean dendrogram based on nucleotides of the full length flaA gene, the flaA short variable region gene and the in silico flaA phylogenic tree of DdeI restriction fragment length polymorphism (RFLP) profiles produced very similar clustering with a diversity index of 0.86 for each of the 3 methods. We conclude that flaA typing based on DdeI RFLP of the PCR products is a cheap, rapid, and reliable method for the epidemiological study of C. jejuni isolates of clinical origin in resource-limited regions or in large-scale population surveillance.