International Journal of Enteric Pathogens
Volume:2 Issue: 4, 2014 Nov

Sarcocystisspp. is zoonotic parasitic pathogen endangering safety of meat and derived meat products such as hamburgers which is among the most popular fast foods worldwide.. The current study aimed to design a protocol for molecular identification of Sarcocystis hominis in commercial hamburgers using PCR-RFLP with target of 18S rRNA.. A total of 25 raw commercial hamburger samples were randomly collected from supermarkets of Yazd city, Iran. Five mm slices from different parts of each sample were selected, well mixed, and then preserved in ethanol 70% at -20°C for the next steps. The genomic DNA was extracted using salting out method. Detection and identification of Sarcocystis isolates were performed using PCR-RFLP. The 18s rRNA gene sequence was mined from GenBank and the specific primer pair was designed using Primer3 software. Restriction fragment length polymorphims (RFLP) analysis was performed using BfaI and RsaI restriction enzymes. The digestion was analyzed, using agarose gel electrophoresis alongside 100base pair DNA ladder.. Among 25 commercial hamburger samples, 17 samples showed a PCR product around 900 bp which could detect Sarcocyst Spp. After RFLP with BfaI, the restriction fragments of 376 bp and 397 bp detected S. hominis or S. hirsuta and fragments of 184 bp, 371 bp and 382 bp detected S. cruzi. After RFLP with RsaI, the restriction fragments of 376 bp and 557 bp detected S. hirsuta and fragment of 926 bp, without any digestion, detected S. hominis. For verification, each species detected in samples was randomly selected and sent for sequencing and the results were analyzed with BLAST.. In conclusion, the current study developed a practical technique to detect the prevalence of S. hominis in meat products such as hamburgers..

Vibrio cholerae is a significant human pathogen worldwide and annually causes some cases of deaths. Contaminated water plays an important role in transmission of this pathogen, which indicates the importance of early diagnosis.. The current study aimed to perform Polymerase Chain Reaction (PCR) on water and wastewater samples to determine the detection limit for Vibrio cholerae.. PCR was performed on the DNA extracted from Vibrio cholerae of the contaminated water and wastewater using ctxA gene specific primers. The accuracy of PCR method to detect these bacteria was also assessed.. The result of PCR performed on the extracted DNA showed a specific 241 base pair band. The limit of bacterial detection for water and wastewater were 40 cfu/mL and 81 cfu/mL, respectively.. In the current study, PCR performance using the ctxA gene specific primers to detect Vibrio cholerae was found highly accurate and specific..

Lactic acid bacteria (LAB) are a major group of probiotics. Isolation of these bacteria is difficult, because they have a complex ecosystem in fermented dairy products.. The aim of this study was to detect Lactobacillus and Lactococcus in a conventional dairy product (Khameh) and study their probiotic characteristics.. To isolateLAB, samples were collected from four different villages. Afterwards, screening was performed in pH = 2.5. The selected strains were examined for their tolerance to acidic pH (3) and 0.3% bile salt. Moreover, the antimicrobial activity of the isolated strains against two pathogenic bacteria, Salmonella typhimurium and Staphylococcus aureus, was assessed using the disc plate method. Finally, the selected strains were identified by polymerase chain reaction (PCR) screening and sequencing.. Among the isolated samples, two strains (Lactobacillus and Lactococcus) were highly resistant to unfavorable conditions and the L1 strain showed the highest antimicrobial activity.. This study showed that the conventional dairy product (Khameh) contained probiotic bacteria, which are capable of fighting against pathogenic bacteria and living in the digestive tract..

Staphylococcus aureusis a serious agent that often colonize dairy products all over the world. Staphylococcal enterotoxins are the essential causes of food poisoningin human societies. Enterotoxin type A is an importantstaphylococcal exotoxin.. The aim of present study was to detect the enterotoxin producing Staphylococcus.aureus within different dairy products collected from Tehran, Iran.. Two hundreds twenty dairy products samples were collected from local dealers across the city. The samples were first screened for S. aureus contaminations. All isolated strains of S. aureus were then investigated for enterotoxin a gene, usind spesific primer sets.. Staphylococcus aureus was isolated from 43% of dairy samples: 22% from milk and 18% from cheese samples. The SEA genes were detected in 10 isolates (22%) originated from raw milk and in two isolates (25%) from domestic cheese.. Since, the staphylococcal enterotoxins are heat stable, heat had no effect on the toxicity of the enterotoxins within positive samples. Our primer stets confirmed previous studies that introduced PCR as rapid, sensitive, and specific method for dairy products screening system. Our data showed that routine screening and surveillance is vital for different food materials including dairy products..

Uropathogenic Escherichia coli (UPEC) O-serogroups with their phylogenetic background are the most prevalent causes of urinary tract infections (UTIs).. The association of O types with phylogenetic background was assessed among E. coli isolates collected from patients with UTI..Patients and In this study, 186 patients with UTI, referred to two hospitals affiliated to Zabol University of Medical Sciences in southeast of Iran, were enrolled during January to July 2013. Phylogenetic groups and serotyping were performed using multiplex-PCR method.. A total of 100 E. coli strains were isolated from the urine samples. The most common types of O antigens were O2 (16.43%), O6 (16.43%) and O18 (13.69%). The phylogenetic analysis showed that 63 O-antigen-positive isolates were mainly segregated from the phylogenetic group B2 (56%) and the substantial prevalence (30%) belonged to the phylogenetic group D.. This was the first report of E. coli serotyping in patient with UTI from southeast of Iran as well as investigation of their relation with phylogenetic pattern by multiplex-PCR. Further studies from other parts of Iran and on other serotypes are recommended..

Urinary tract infections are a significant health problem, with Escherichia coli as a primary pathogen in approximately 80% of cases. The pathogenesis of E. coli in urinary tract infections is attributed to the production of virulence factors and phylogenetic background groups.. The aim of this study was to determine differences in prevalence of virulence factors of E. coli isolates from phylogenetic groups B2 and D, collected from patients with urinary tract infections.. A total of 100 E. coli isolates were identified by conventional biochemical tests from patients with urinary tracts infections (UTIs) in teaching hospitals of Zabol, Iran. DNA was extracted using the boiling method. Analysis of phylogenetic groups, along with detection of virulence factor genes was performed by the multiplex-PCR method. Associations were assessed between type 1 fimberia-encoding gene, siderophore receptor encoding genes and hemolysin encoding gene among 55 B2 group E. coli isolates and 22 D group E. coli isolates. Statistical analysis was performed using the Fisher exact test.. Phylogenetic analysis showed that 55 and 22 of 100 isolates belonged to the B2 and D phylogenetic groups, respectively. The hlyA, iroN, iucD and fimH genes were present in 29 (52.72%), 22 (40%), 46 (83.63%) and 55 (100%) isolates belonging to the phylogenetic group B2, whereas in 2 (9.09%), 2 (9.09%), 10 (45.45%) and 22 (100%) isolates belonging to the phylogenetic group D, respectively. The comparison showed that there was a significant difference between the presence of hlyA and iroN genes in isolates belonging to the phylogenetic group B2 and D (P ≤ 0.05).. This study determined that strains belonging to group B2 are the most important and abundant E. coli strains causing urinary tract infections..

Meat products could be sources of enter pathogens. Identification of meat species in different foods could help us in molecular epidemiological studies of pathogens transmitted by meat.. In this study, we targeted cytochrome b for identification of beef in handmade hamburgers..Patients and A total of 110 raw handmade hamburgers were collected from different areas of Yazd city, Iran, during spring of 2013. Genomic DNA was extracted using the salting out method. The beef cytochrome b gene was amplified using specific primers. Analysis of the amplicons was done with agarose gel electrophoresis usinga100 base pair (bp) DNA ladder.. The results showed that among the 110 handmade hamburger samples, 10 (9.09%) samples did not containany cow meat while 100 samples contained cow meat.. We used an appropriate molecular method for controlling raw and processed products. Therefore, this study would be useful for control of correct labeling and protection of consumer’s rights..

Klebsiella pneumoniais producer of carbapenemase (KPC) an emerging pathogen with propensity to malady in weak patients, increasing their morality rates.Carbapenemaseis an enzyme that destroys all beta-lactam antibiotics and is the therapeutic choice for infections with extended-spectrum beta-lactamase (ESBL)-producing organisms.ESBLESBLs are penicillin, narrow spectrum also third-generation cephalosporin, and monobactams hydrolyser and checkrein by clavulanic acid.. The present study was performed to separate and identify the carbapenemase resistance pattern of multidrug-resistant (MDR) and ESBL-positive K.pneumoniaas well as its prevalence among different wards and various clinical specimens in Isfahan..Patients and Over 500 different clinical samples were collected from different sections of great teaching hospitals in Isfahan, in which K. pneumonia isolates were identified by IMVIC and urease standard biochemical tests and also were confirmed by determination of the ureD Gene. Antimicrobial susceptibility tests were performed as standard disk-diffusion on Mueller-Hinton agar (Merck, Germany) based on the instructions of Clinical Laboratory Standards Institute (CLSI, 2013). Sieving and phenotype conformation of ESBL isolates were performed by double disc synergy test (DDST), and then, the strains identified as ESBL were test by carbapenem, ertapenem, imipenem andmeropenem. Finally, the statistical analyses were performed using the WHONET software version 5.6.. Of clinical isolates of K.pneumonia, 142 were confirmed using biochemical methods and then the molecular confirmation was performed by PCR of the ureD gene. Of the total isolates, 57% were from males and 43% from females; 120(84%) of isolates were recognized as MDR. The highest rates of resistance were related to piperacillin (80%), ceftazidime (76%), and cefotaxime (73%). Among these MDR isolates, 101 (71%) were detected as ESBL, using DDST. The ward and the clinical specimen with the most prevalence were ICU with 55 (38.7%) and urine with 61(42.9%) samples, respectively. The lowest prevalence was related to the neurosurgery ward with 8 (5.6%) samples and the clinical specimen with the lowest prevalence was cerebrospinal fluid (CSF) with 2 (1.4%) samples. The susceptibility patterns to carbapenem agents were as follows: ertapenem50.7%, meropenem 44.8% and imipenem35.8%.. In this study, the prevalence of carbapenem-resistant K.pneumoniae was high in positive ESBL isolates, which can create significant therapeutic problems. According to the resistance pattern of ESBL-positive isolates for carbapenems in this research, ertapenem can probably serve as a suitable therapeutic option for uncomplicated infections by ESBL-producing K.pneumoniae instead of imipenem and meropenem..

Salmonella is one of the most widespread zoonotic enter pathogenic microorganisms found in the global food chain. Poultry and Poultry products have been identified as one of the important foodborne sources of Salmonella. Pulsed-Field Gel Electrophoresis (PFGE) is a gold standard typing method for identification of Salmonella isolates during outbreaks and epidemiological investigations.. The aim of this study was to carry out molecular typing of Salmonella enterica spp. by PFGE technique.. All 47 Salmonella isolates were serotyped and then subjected to PFGE. Total isolates were analyzed by means of the molecular technique XbaI PFGE.. In the current work, PFGE and serotyping were used to subtype 47 Salmonella isolates belonging to 22 different serotypes and derived from poultry. Thirty-nine PFGE patterns out of 47 isolates were obtained. The Discrimination Index (DI) by serotyping (0.93) was lower than PFGE (DI = 0.99).. In conclusion, molecular methods such as PFGE can be used for epidemiological characterization of Salmonella serotypes..

Nano composites are widely used in medical sciences recently. Identification of chemical mutagens is an important issue in drug safety.. The aim of this study was to investigate mutagenicity and antibacterial activity of various generations of poly (amid amine) (PAMAM) dendrimers and agonic acid poly (amid amine) (PAMAM) Nano composite G2 on enteric pathogenic bacteria.. Disc diffusion method, MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) determination were performed for antibacterial activity survey. Mutagenic properties were determined by Ames assay.. Various dilutions of PAMAM generations (G2, G3, G4 and G5) and agonic acid PAMAM Nano composite G2 had antibacterial effect on Escherichia coli, Salmonella enterica, Salmonella typhimurium, Enterococcus faecalis and Staphylococcus aureus. In Ames assay, reverted colonies were increased by PAMAM generations increasing. Moreover, reverted colonies Ames assay were lower when Nano composite G2 was applied.. PAMAM generations and agonic acid PAMAM Nano composite G2 contain compounds with therapeutic potential and antibacterial characteristics, which can be used in medicine. Because some chemicals have mutagenic and carcinogenic properties, identification of these chemical is of great importance..