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Historically, tuberculosis has been the leading cause of death throughout human history. Tuberculosis infection (TB) causes by Mycobacterium tuberculosis that is very dangerous and can affect any parts of the body, especially lungs. Tuberculosis infection still remains a serious threat to human public health due to its contagious nature, capability to stay latent form in host for indefinite time and then appear as active disease. It is estimated that one third of world’s population, nearly 2 billion persons are infected with Mycobacterium tuberculosis. Transmission occurs among people through inhalation of infected droplets. Lungs and especially alveolar macrophage are primary sites of infection. Mycobacterium tuberculosis bacilli by preventing fusion of phagosome with lysosome can remain alive inside the macrophages. Such situation defined as latent infection. In fact, persons with latent tuberculosis infection (LTBI) are only infected with M. tuberculosis without any sign of infectious. Latent infection in compared with active infection is not contagious, but in about 10-5 percent of people will develop active tuberculosis especially in elderly and people who use immunosuppressive drugs. Pulmonary TB is an active form of tuberculosis infection in which bacteria can spread among people by infected droplets. So identifying and treating people with latent TB infection can significantly reduce the progression of latent form to active infection. The tuberculin skin test (TST) is the most widely used test in worldwide that is applied to determine a person who is infected with M. tuberculosis. TST provide valubale information for diagnosis LTBI however its specificity can be reduced by bacillus Calmette-Guérin (BCG) vaccination and infected with non-tuberculous mycobacteria (NTM). In TST test host hypersensitivity responses to Purified protein derivative (PPD) from mycobacterium are evaluated. TST positive reaction indicates the presence of high risk for acquiring TB infection or progression of latent tuberculosis to active form. Previous studies indicated that there is correlation between TST response and subsequent risk of active TB. Experimental evidence has shown that treatment of latent infection in the basis of positive TST reduces the risk of active TB. Although TST is far from gold standard but it's low cost and simplicity make it a suitable laboratory test especially in developing country.

After live attenuated and subunit vaccines, DNA vaccines were introduced as a third generation vaccine in the field of vaccinology. This type of vaccine is a promising approach to deal with infectious agents in the future. Although, many aspects of this type of vaccine has not yet been identified, its use has been initiated in humans and clinical trials, and several DNA vaccines have been developed against veterinary infectious diseases. This generation of vaccine has provided new approaches to deal with and control existing diseases. In addition to infectious diseases, this type of vaccine can also be used against different types of tumors. Despite numerous attempts, only one type of DNA vaccine has been approved for use in human. The present study focuses on biology, advantages, and disadvantages of DNA vaccine and investigates its capacity in stimulating different types of immune responses.

Despite advances in the vaccinology and chemotherapy in the past century, tuberculosis is still responsible for two million deaths every year. Emergence of multi-drug resistant strain and coinfection of TB-HIV make it a serious concern. Treatment and control of tuberculosis is a great health burden in every community. Active tuberculosis in children has very severe consequences especially those who are under 5-years-old, therefore vaccine indication should be taken. Bacille Calmette-Guérin (BCG) is a live attenuated strain of Mycobacterium bovis that has been used for providing immunity or protection against tuberculosis (TB). In addition, BCG provides relative protection against leprosy and Buruli ulcer, it also can be used for treatment of bladder cancer. BCG is the most widely administered vaccine around the world. It has been given to over three billion individuals over the past decades. At first it was developed in 1908 at the Pasteur Institute in Lille by Albert Calmette and Camille Guérin. In fact BCG is a strain of Mycobacterium bovis that bear deletion in its genome following too long subculture in special media. Deletion in region of deletion 1 (RD1), a specific region of Mycobacterium bovis genome, has decreased pathogenicity of BCG strain. Following culture of BCG on different media since 1921 make genetic variation in the BCG strains that have specific characteristics. BCG should begin given to only immune-competent individuals and should not be administered to immunocompromised people. This vaccine is not effective in people formerly infected or sensitized with environmental mycobacteria. Previous meta-analysis studies indicate that BCG has variable range of protection from 0 to 80 percent against pulmonary TB, but is very effective against severe disseminated forms such as meningitis and miliary form of TB. Despite many research and develop new generation vaccine against TB, BCG vaccine still remains as the only effective vaccine because many efforts to replace it with better ones were unsuccessful.

Drug resistance is one of the most problems in controlling microbial infections which assumes to be ever-increasing problem all through the world. Production of extended-spectrum β-lactamases enzyme (ESBLS) can cause a resistance to antibiotics of gram negative bacteria. The main purpose of this study was to determine antibiotic sensitivity patterns and SHV-1 genes frequency in collected urinary samples from hospitalized patients in Ardebil. 400 isolated Enterobacteriaceae from urinary samples were recognized using an ordinary biochemical method. Antibiotic sensitivity test was conducted by Kirby and Bauer. The combined disk method was also utilized as a confirmatory test. The results were compared to clinical and laboratory standards institute (CLSI) standards. Finally، ESBL positive isolates were investigated by PCR method regarding the SHV-1 gene. From the total of 400 urinary isolates Enterobacteriaseae resistance to Ampicilin، Nalidixicacid، Co-trimoxazole، Cefotaxime، Ceftazidime، Ceftriaxone، Ciprofloxacin Ceftizoxime، Cefixime، Gentamycin، Imipenem were 82. 5، 62. 3، 67، 36، 49. 5، 50. 3، 52، 36، 41، 24. 8 and 7. 7 percents، respectively. 150 isolates (37. 5%) were positive ESBL، and among all، 28 isolates (18. 7%) contained SHV-1 gene. According to obtained results from the study، regarding high percentage of resistance to antibiotics and high reduction of ESBLS in bacteria from who suffered from urinary infections، taking some logical steps for prevention seems to be essential.

Resistant microbial strains are a serious threat to public health in different societies. A mong the extended-spectrum β-lactamases (ESBL) producing strains the Enterobacteriaceae family which is considered as the main factors producing urinary tract infections, have created many problems in treatment of this kind of infections. This study was conducted to determine the frequency of β-lactamase TEM-1 gene in Enterobacteriaceae isolated from urine samples in Ardabil city. Within 6 months, 400 urinary isolates of Enterobacteriaceae of inpatients and outpatients were collected in Ardabil hospitals and were identified by standard methods. Antimicrobial susceptibility of isolates was tested by disk diffusion method, and ESBL producer confirmatory test was conducted using combined disk. Finally, the frequency of β-lactamase TEM-1 gene in producing extended-spectrum β-lactamases strains was investigated using PCR. From 400 isolates of Enterobacteriaceae, 150 cases (37.5%) were ESBL producing. PCR results showed presence of the TEM-1 gene in 69 cases (46%). The frequency of this gene in isolates of Enterobacter (Aerogenes, Cloacae), Klebsiella (Pneumoniae, Oxytoca) and E. coli was obtained to be 62.5%, 54.5% and 44.8%, respectively. Proteus mirabilis and Serratia marcescens strains were lacking these genotypes. As regards the presence of TEM-1 gene, there is also increasing in other members of the Enterobacteriaceae family including Klebsiella and Enterobacter in addition to E. coli, therefore sufficient identification of this strains is necessary to prescribe the right medicine.

Urinary tract infections (UTIs) caused by extended-spectrum beta lactamase (ESBL)-producing bacteria have become a growing problem worldwide. The aim of this study was to investigate the prevalence of ESBL-producing bacteria in urine samples of hospitalized patients in Imam Khomeini hospital of Ardabil over a period of October 2011 to August 2012. A total of 400 urinary pathogens isolated from urine samples were included in the study. All isolates were identified by routine biochemical methods and antimicrobial susceptibility testing carried out by Kirby-Bauer method. Confirmatory test for production of ESBLs was performed by the combination disk tests. The results were interpreted according to the recommendation of CLSI. Of 400 isolated bacteria, 267 were E.coli, 39 Klebsiella pneumoniae, 17 Klebsiella oxytoca, 16 Enterobacter cloacae, 15 Enterobacter aerogenese, 6 Enterobacter agglomerans, 8 Enterobacter sakazakji, 3 Citrobacter froundi, 2 Citrobacter diversus, 3 Proteus mirabilis, 4 Edvardsiella tarta, 3 Serratia marcesecens and 17 Morganella morganii all of which then were analyzed. ESBL was detected in 36.75% (147) of isolates. Eighty nine E.coli cases (77.4%), 15 Klebsiella pneumonia (13.04%), 2 Klebsiella oxytoca (1.74%), 3 Enterobacter aerogenese (2.6%), 4 Enterobacter cloacae (3.5%), 1 Citrobacter ferundi (0.86%), and 1 Morganella morganii (0.86%) were detected as ESBLs producers, respectively. Based on the results of this study, broad-spectrum beta-lactamase production in bacterial strains isolated from patients with urinary tract infection was very high and almost 40% of all bacterial species isolates were ESBLs producers. Because of the high prevalence of ESBL-producing bacteria in the urinary tract infections in hospitalized patients of our area, we would strongly suggest that the ESBL production should be considered in these patients.

Group B streptococci (GBS) are the major cause of neonatal and maternal infections. They are susceptible to penicillin, ampicillin and first-generation cephalosporins. However, resistance to other antibiotics such as erythromycin and clindamycin is common among GBS strains. The aim of this study was to evaluate the antimicrobial activity of allicin against colonizing GBS strains in vitro. Garlic extract was prepared and allicin was purified using semi-preparative HPLC procedure. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of allicin were determined for 52 GBS strains using microdilution method in Todd Hewitt broth medium. MIC of allicin was 64-128 µg/mL (MIC90 = 128) and MBC of allicin was 128 to 512µg/mL (MBC90= 256) for GBS strains. The results of this study showed that allicin can inhibit growth of GBS in vitro. Further studies on allicin might be worthy of evaluation as a therapeutic agent in treatment of GBS infections.

Brucellosis is one of the most common zoonotic diseases in Iran. In most cases، the diagnosis of brucellosis is difficult not only because of its clinical similarity to many infectious and noninfectious diseases، but also because diagnostic methods often fail to detect organisms. PCR is a rapid and safe diagnostic method applied to the diagnosis of brucellosis. The purpose of this study was to determine the sensitivity and specificity of PCR for diagnosis of human brucellosis by using serum samples. This study which was done to evaluate diagnostic tests included30 serum samples from patients with clinical presentation of brucellosis with positive Wright test and serum samples of30 healthy people with negative Wright test. These samples were examined by PCR. PCR results were positive for 15 samples of the patients group in comparison with 4 samples from the 30 healthy subjects. The sensitivity and specificity of PCR were 50% and 86. 6%، respectively. Although in some studies، the preferred sample for diagnosis of brucellosis was serum، in this study، PCR on serum samples did not indicate high sensitivity and specificity in diagnosis of brucellosis. Hence، using a combination of methods for diagnosis of human brucellosisis suggested.

Industrial wastewater included the cyanide is one of the important sources of environmental pollution which founded in Industrial wastewater which are harmful for human health and environment. Therefore, the purpose of this research that was fundamental designed is investigation of Removal of cyanide from aquatic solution by using of iron and copper powder in experimental scale. At first, pilot was designed. Then, acquired pH optimum equal to 2,7 for copper and iron by variation pH= (2,4,6,8,12) and constant other parameters. The effect of initial cyanide concentration (40,60,80 mg/l), initial iron and copper dosage (0.08-1 g/100CC) and contact time (15-12 min) studied at the constant of optimum pH. The result showed removal efficiency Increased from 46.6% to 90.56% and 31% to 93.78% for copper and iron by increasing of contact time from 15to 120 minute in constant conditions, respectively. Also result showed Removal efficiency decreased and increased by increasing initial cyanide concentration and initial iron and copper dosage. The results showed equilibrium data were explained acceptably by Langmuir isotherms and kinetic parameters were obtained by application of Langmuir&Hinshelwood equation. The results showed that removal of cyanide can be quick and effective done by iron and copper in experimental scale.

Different factors increase risk of disease transmission in women's barbershop and disinfection of instruments, as a major preventive measure, plays an important role in the control of disease transmission. Therefore, present study was conducted to investigate the quality of barber tools disinfection in women salons in Ardabil in 2009. In a cross-sectional study, 96 women salons were randomly selected. Data were compiled using a questionnaire, observation, and recording results of microbial cultures from barbering tools and analyzed using χ2 and descriptive statistics. Personal shaving kits were being used only in 5.2% of barbershops and 56 % of barbers applied Micro 10 as a disinfectant of barbershop tools. 64.6 % of samples were microbiologically positive and Staphylococcus aureus was detected in 53% of positive samples. Positive results were significantly higher in barbershops that did not follow standard procedure of tools disinfection (p < 0.0001). As a result of our study we suggest the following points to improve population health in the barbershops: training on proper disinfection techniques, promotion of Micro10 application and avoid of unhealthy behaviors in barbershops.

E. coli is an opportunistic and pathogenic bacterium in human. It is a fecal contamination indicator of the water. The aim of this study is to investigate the efficiency of ultra violet radiation in disinfection of E. coli in aquatic environments in a batch system. At first, reactor was designed and made. The effects of pH, exposure time and initial inoculum were studied. Kinetic parameters were obtained by application of zero, first and second-order equations. The result showed that removal efficiency decreased with increase of initial inoculum and the kinetics of disinfection was described by first-order model. The result also showed that removal efficiency augmented with increasing exposure time and pH. The results of this study shows that ultra violet radiation can be used as an effective disinfection method for E. coli in aquatic environments.

This study was prepared to determine the frequency of Staphylococus aureus nasal colonization among intravenous drug abusers with respect to this fact that the rate of colonization is dependent on various factor including addiction behaviours. There wasnt any native study on this subject. The purpose of this study was to prepare the basic data of S.aureus nasal colonization among intervenous drug abusers, in order to reducing the incidence and nasal carriage rates of S.aureus infections. This was a prospective cross sectional study that included all of intravenous drug abusers who referred to three hospitals of Tehran from 2005 to 2006. Specimens for culture were obtained by swabbing anterior nares. Swabs were inoculated into nasal chapman broth and incubated at 35 °C for 48 hours. Isolated colonies were further subjected to identification and antimicrobial susceptibility testing. The related data were collected using patients` medical files and analyzed with using SPSS 11. Staphylococcus aureus was grown in 38 cultures (26.2%). We did not find any significant relationship between variables such as, economic condition, methods of using drugs, frequency of drug use, infection with different viruses, gender and colonization by Staphylococcus aureus. We observed lower nasal colonization with Staphylococcus aureus among patients. We suggest preparing similar study in order to clarify the role of different factors that have effect on the rate of nasal colonization with Staphylococcus aureus.

Tuberculosis is more prevalent in developing countries and death from tuberculosis meningitis is strongly associated with delays in diagnosis and treatment. Polymerase chain reaction (PCR) has been incorporated as a diagnostic tool for the diagnosis of tuberculosis. The rapid results and greater sensitivity compared to traditional microbiological methods makes PCR a suitable technique in tuberculosis, especially in tuberculosis meningitis, when diagnosis is difficult or when rapid diagnosis is needed. However, the possibility of false positive and false negative results must be considered. The aim of this study was to compare the conventional bacteriology (culture Ziehl- Neelsen staining) with polymerase chain reaction (PCR) technique for rapid diagnosis of tuberculosis meningitis. This study included 25 clinically diagnosed patients that were suspected to have tuberculosis meningitis and 10 other bacterial or viral meningitis patients were investigated. DNA was extracted from CSF and the NESTED PCR using specific primers were done. In 25 samples, Mycobacterium tuberculosis DNA was detected in 9 (36%) by PCR, 2(8%) and 1(4%) with culture and direct smear was obtained, respectively. whereas no DNA bands were detected in patient with the other 10 meningitis. The entire procedure was repeated and the same result was obtained. The findings of this study indicated that PCR is a powerful method for rapid and sensitive diagnosis of tuberculosis meningitis. In a way that it decreases obtaining the results from several weeks in bacteriological methods to one to two days, especially in smear negative patients. This is very important in tuberculosis meningitis because it is a medical urgency and needs rapid diagnosis and early treatment.

Brucellosis is one of the most common zoonotic diseases in Iran and is endemic in all parts of the country. Patients recorded in 1988 were 71,051(132. 4 per 100,000). Brucella species are facultative intracellular bacteria, and therefore a limited number of antibiotics are effective against these organisms. The aim of this study was theevaluation of in vitro sensitivity of various antimicrobial agents against 47 brucella melitensis strains isolated from blood culture. The susceptibility of 47 Brucella melitensis isolates derived from clinical samples were tested in vitro. The minimum inhibitory concentrations (MICs) of the tested antimicrobials were measured by the agar dilution method.MIC90 and MIC50 values were defined as the lowest concentration of the antibiotic at which 90 and 50 percent of the isolateswere inhibited, respectively. The NCCLS criteria for slow growing bacteria were considered to interpret the results. Tetracycline (MIC50: 0.13μg/ml, MIC90: 0.25 μg/ml) and streptomycin (MIC50:0.003 μg/ml, MIC90:0.25 μg/ml) had the lowest MICs in vitro against the B. melitensis strains. Norfloxacin had the highest (8 μg/ml) MIC90 value. More than halfisolates presented reduced susceptibility to rifampin (MIC value: 2μg/ml). Brucella isolates remain susceptible in vitro to most antibiotics used for treatment of brucellosis. There is no significantly important resistance problem for antibiotics targeted against Brucella species in Iran. However, since rifampin is commonly used for prevalent diseases such as tuberculosis, the regional susceptibility pattern of rifampin should be assessed periodically.