PubMed | Islamic Azad University of Arak and Reference Health Laboratories Research Center
Type: Journal Article | Journal: Cell journal | Year: 2014
In-time diagnosis of Streptococcus pneumoniae (S. pneumonia) can play a significant role in decreasing morbidity and mortality rate. Applying molecular methods has gained popularity due to the existing limits of routine diagnostic methods. Examining the expression of different genes of this bacterium through different molecular methods suggests that lytA gene has a higher sensitivity and specificity in diagnosis of Streptococcus pneumoniae. The aim of this study was to evalutate lytA gene expression in diagnosis of invasive S. pneumonia in culture positive specimens by real-time polymerase chain reaction (PCR).IIn this a descriptive study, All received specimens were isolated to identify S. pneumoniae. DNA was then extracted and after optimizing the test and determining the detection limit, samples were tested by real-time PCR using lytA gene primers.Twenty seven isolates were diagnosed as S. pneumoniae. In all, the extracted DNA was positive in real-time method. The electrophoresis of the products also confirmed the presence of single product b along with the 53 base pair fragment. The detection limit of the test was less 6 colony forming unit (CFU).Real-Time PCR seems to provide reliable and rapid results. We suggest that this test should be conducted on the preliminary isolated specimens, since applying various biochemical tests need one extra working day.
PubMed | Tarbiat Modares University, University of The Sunshine Coast, Tehran University of Medical Sciences, Reference Health Laboratories Research Center and Islamic Azad University at Tehran
Type: Journal Article | Journal: Laboratory medicine | Year: 2015
The epidemiology of salmonellosis is complex because of the diversity and different serotypes of Salmonella enterica (S. enterica) that occur in different reservoirs and geographic incidences.To determine the genotype distribution and resistance-gene content of 2 classes of integron among S. enterica isolates.Thirty-six S. enterica species were isolated and tested for their serological distribution and the resistance-gene contents of 2 classes of integron, as well as for their genetic diversity, using the pulsed-field gel electrophoresis (PFGE) genotyping method.Serogroups E (36.1%) and D (30.5%) were dominant among the isolates. All of the isolates in serogroup D belonged to the serovar enteritidis. The aadA1 gene was found within all resistance-gene cassettes. We observed 4 common and 26 single pulsotypes among the isolates, which indicated a high degree of genetic diversity among the isolates. Using the PulseNet International standard protocol, it was found that these isolates were different from those reported previously in Iran.The presence of a few common and new pulsotypes among the isolates suggests the emergence and spread of new clones of S. enterica in Iran.
PubMed | Tehran University of Medical Sciences, Shahid Beheshti University of Medical Sciences, Islamic Azad University at Karaj, Iran National Institute of Genetic Engineering and Biotechnology and 2 more.
Type: | Journal: BMC microbiology | Year: 2015
To investigate antibiotic resistance, the occurrence and distribution of class 1 and 2 integrons in multidrug- resistant Staphylococcus aureus isolates from hospitals in Tehran, Iran. The isolates were examined for susceptibility to antimicrobial agents. The mecA gene, class 1 and 2 integrons were detected by PCR. Integrase positive strains were further analysed for the presence of resistance gene cassettes using specific primers and were sequenced.Among 139S.aureus isolates, 109 (78.4%) and 112 (80.5%) strains were considered as multidrug resistant and mecA positive, respectively. Class 1 integrons and internal variable regions were found in 72.6% (101/139) and 97% (98/101) and class 2 integrons and variable regions also in 35.2% (49/139) and 65.3% (32/49) of S.aureus clinical isolates, respectively. Twelve distinct cassette arrays were found, containing genes encoding resistance to -lactams, aminoglycosides, streptothricin, trimethoprim, chloramphenicol,a putative glucose dehydrogenase precursor and a protein with unknown function. Gene cassette arrays aadB, aadA2 and dhfrA1-sat2-aadA1 were common in S.aureus isolates. We detected a completely new gene cassettes which contained aadB, oxa2, aacA4, orfD-aacA4-catB8, aadB-catB3, orfD-aacA4 and aadB-aadA1-cmlA6 of class 1 and dhfrA1-sat2-aadA1, dhfrA11, dhfrA1-sat2 of class 2 integrons.This is the first study to report carriage of class 1 and 2 integrons and associated gene cassettes among in S.aureus isolates from Iran.
PubMed | Middle East Liver Diseases Center, Mashhad University of Medical Sciences, Tehran University of Medical Sciences, Reference Health Laboratories Research Center and Shahid Beheshti University of Medical Sciences
Type: Journal Article | Journal: Hepatitis monthly | Year: 2014
Histopathologic assessment of liver tissue is an essential step in management and follow-up of non-alcoholic fatty liver disease (NAFLD) while inter- and intra-observer variations limit the accuracy of these assessments.The aim of this study was to assess the inter- and intra-observer reproducibility of histopathologic assessment of liver biopsies based on NAFLD activity score (NAS) scoring system.The anonymous liver biopsy samples of 100 consecutive NAFLD suspected adults were randomly assigned to four pathologists. Then, the samples were randomly reassigned to the pathologists for the second time in a way that each sample would be evaluated by two different pathologists. Biopsies were revisited by their first evaluator after two months. The results were reported based on NAS scoring system.Inter-observer agreement of the pathology scores based on NAS scoring system was acceptable for steatosis, lobular inflammation, and fibrosis, but not for hepatocyte ballooning. The intra-observer agreement was acceptable in all scales, with lowest intra-class correlation observed for lobular inflammation.NAS scoring system has good overall inter- and intra-observer agreement, but more attention should be given to defining the hepatocyte ballooning and lobular inflammation, and training the pathologists to improve the accuracy of pathology reports.
PubMed | Tarbiat Modares University, Shahid Beheshti University, Ahvaz Jundishapur University of Medical Sciences and Reference Health Laboratories Research Center
Type: Journal Article | Journal: Iranian biomedical journal | Year: 2016
Enteric viruses, particularly human rotavirus and norovirus, have been shown to replace bacteria and parasites, as the most common pathogens responsible for acute diarrhea. However, there are still few epidemiological data on the simultaneous occurrence of these viruses in Iran. In this regard, the aim of this study was to assess the useful epidemiological data on the gastroenteritis associated with rotavirus-norovirus mixed infection and to examine the prevalence of norovirus genogrouping among children aged less than five years old in Iran.A total of 170 stool samples were collected from children under five years of age with the clinical signs and symptoms of acute gastroenteritis, from May 2013 to May 2014. For the detection of both rotavirus and norovirus, total RNA was extracted from all samples, followed by reverse transcription polymerase chain reaction (RT-PCR). For both detected rotaviruses and noroviruses, genogrouping was performed.Of 170 samples, 49 (28.8%) and 15 (8.8%) samples were found to be positive for rotavirus and norovirus infections by RT-PCR. Interestingly, 6 (3.5%) patients were positive for both infections. Among the 15 norovirus-positive patients, 13 (86.6%) and 2 (13.3%) belonged to genogroups GII and GI.The norovirus genogroup GII and rotavirus lead to the serious infections in children with acute gastroenteritis. However, more well-designed studies are needed to further elucidate the role of other enteric viruses in acute gastroenteritis.
Aghaei A.A.,Kerman Medical University |
Rassi Y.,Tehran University of Medical Sciences |
Sharifi I.,Kerman Medical University |
Vatandoost H.,Tehran University of Medical Sciences |
And 4 more authors.
Asian Pacific Journal of Tropical Medicine | Year: 2014
Objective: To identify the Leishmania species in infected sand flies by Real-time PCR coupled with HRM analysis. Methods: Real-time PCR coupled with HRM analysis targeting the first internal transcribed spacer (ITS1) of nuclear ribosomal DNA as the genetic marker was used to identify and distinguish Leishmania species in sand flies specimens. Results: Three out of 115 females of Phlebotomus sergenti (P. sergenti) (2.6%) were positive to Leishmania tropica (L. tropica). Conclusions: This is the first report on P. sergenti as the main and proven vector of anthroponitic cutaneous leishmaniasis in Dehbakri County using Real-time PCR coupled with HRM analysis. This method is rapid, sensitive and specific for diagnosing of parasites in infected Sand flies and ideal for large scale genotyping projects. © 2014 Hainan Medical College.
Oshaghi M.A.,Tehran University of Medical Sciences |
Rassi Y.,Tehran University of Medical Sciences |
Hazratian T.,University of Tabriz |
Fallah E.,University of Tabriz |
Rafizadeh S.,Reference Health Laboratories Research Center
Journal of Vector Borne Diseases | Year: 2013
Background & objectives: Zoonotic visceral leishmaniasis is caused by Leishmania infantum, which is transmitted to humans by bites of phlebotomine sandflies and is one of the most important public health problems in Iran. To detect and identify the Leishmania parasites and their corresponding vector(s), an investigation was carried out in Azarshahr County, a new and important focus of the disease in East Azerbaijan province in northwestern Iran during late April to late October 2010. Methods: Sandflies were sampled using sticky papers (A4 white paper soaked in castor oil) from inside and outside of the houses and animal shelters, close to the vegetation and crevices. The head and three last abdomen segments of the specimens were removed and mounted in Puri's medium for species identification. The rest of body was subjected to molecular methods for detection of leishmanial parasites. Results: Among 400 female sandflies tested by polymerase chain reaction (PCR) of kDNA, ITS1-rDNA, and CPB genes of the parasite followed by restriction fragment length polymorphism (RFLP), only 2 out of 8 Phlebotomus tobbi were positive to L. infantum parasites. Conclusion: The results indicated that, P. tobbi was the only species found infected by L.infantum and the principal vector of the disease agent to human.
Rafizadeh S.,Reference Health Laboratories Research Center |
Rafinejad J.,Tehran University of Medical Sciences |
Rassi Y.,Tehran University of Medical Sciences
Journal of Arthropod-Borne Diseases | Year: 2013
Background: Scorpion sting is a major health problem in Iran. The aim of current study was to measure the incidence rates of scorpion stings, mortality, recovery, and affected age groups. The results of treatment with and without anti venom also were considered in the entire country during 2009.Methods: All the data were collected from emergency section of different hospitals and then were analyzed by related software. The responsibility of such data collection and surveillance is related to the Department of Violence and Injury, Ministry of Health and Medical Education of Iran.Results: A total incidence of 59.5/100000 was found for the 12-month period. During the study period the most and the least cases were reported from Khuzestan and Mazandaran Provinces with incidence of 541 and 0 per 100000 respectively. Totally 40220 anti venom vials were used, i.e., the ratio of 91 vial/ 100 affected cases. The stings occur mainly in rural areas (57.7%). Young people with theage group of 15-24 years old were the most victims of stings.The mortality and recovery rates of cases who had received anti venom less than 6 h of stings were calculated as 0.01% and 99.9% respectively.Conclusion: The high incidence of scorpion stings in Iran especially in Khuzestan suggests the necessity of preventive programmes for decreasing the incidence. Such programmes could start by community educating in the high prevalent areas. In addition prompt and local treatment is particularly important for infants and pre-school children.
PubMed | Tarbiat Modares University and Reference Health Laboratories Research Center
Type: Journal Article | Journal: Iranian journal of microbiology | Year: 2015
Salmonella is an important food-borne pathogen in humans. Strains of Salmonella spp. that producing extended-spectrum -Lactamases have become a concern in medicine regarding both antimicrobial treatment and infection control program. The objective of this study was to describe the antibiotic susceptibility, ESBL production and determining the prevalence of the bla CTX-M-1 group among clinical isolates of Salmonella spp.A total of 110 Salmonella isolates collected from four Tehran hospitals during May 2012 and April 2013. The specific monovalan Salmonella antisera were used for serogrouping of Salmonella isolates. Antibacterial susceptibility was determined by disk diffusion and ESBL phenotype was confirmed by combination disk method. The bla CTX-M-1 group was identified by PCR with specific primers. The transferability of the bla CTX-1 group was tested by conjugation with broth matting method.The prevalence of Salmonella serogroups consist of 56.4% serogroup D, 13.6 % serogroup C, 10 % serogroup B, and 1.8 % serogroup A and 18.2% other serogroups. Maximal resistance in Salmonella isolates was noticed against trimethoprim-sulfamethoxazole (63.6%) and nalidixic-acid (47/3%). All isolates were susceptible to imipenem and ciprofloxacin. Four isolates (3.6%) showed ESBLs phenotype. All Salmonella spp. that produce ESBls have bla CTX-1 genes group. A conjugative plasmid containing bla CTX-1 group was found in one Salmonella isolate.This study demonstrates the predominant presence of the gene encoding CTX-M-1 group among ESBLs producing of Salmonella spp. They can transmit to bacteria of this genus or even other genera of enteric bacteria.
Anjarani S.,Reference Health Laboratories Research Center |
Safadel N.,Reference Health Laboratories Research Center |
Dahim P.,Reference Health Laboratories Research Center |
Amini R.,Reference Health Laboratories Research Center |
And 2 more authors.
Iranian Journal of Public Health | Year: 2013
In September 2007 national standard manual was finalized and officially announced as the minimal quality require-ments for all medical laboratories in the country. Apart from auditing laboratories, Reference Health Laboratory has performed benchmarking auditing of medical laboratory network (surveys) in provinces. 12th benchmarks performed in Tehran and Alborz provinces, Iran in 2010 in three stages. We tried to compare different processes, their quality and accordance with national standard measures between public and private hospital laboratories. The assessment tool was a standardized checklist consists of 164 questions. Analyzing process show although in most cases implementing the standard requirements are more prominent in private laboratories, there is still a long way to complete fulfillment of requirements, and it takes a lot of effort. Differences between laboratories in public and private sectors especially in laboratory personnel and management process are significant. Probably lack of motivation, plays a key role in obtain-ing less desirable results in laboratories in public sectors.