فهرست مطالب محمد یوسف علیخانی

 Uropathogenic Escherichia coli (UPEC) is the most prevalent causative agent of urinary tract infections (UTIs) in both community and hospital settings. Annually about 150 million people globally develop UTIs, resulting in increased healthcare costs. The current study examined the identification and the frequency distribution of virulence factors among fluoroquinolones-resistant (FQs-R) and fluoroquinolones-susceptible (FQs-S) UPEC strains in Hamadan hospitals, west of Iran.

 One hundred-seventy urine samples were collected consecutively from inpatients at three hospitals in Hamadan from March to September 2018. The UPEC isolates were identified using biochemical tests and polymerase chain reaction (PCR). The disk diffusion and the broth microdilution methods determined the antimicrobial susceptibility and the minimum inhibitory concentration (MIC) of Ciprofloxacin. The multiplex-PCR method investigated the prevalence of pap, aer, and hly genes.

Among 170 urine samples collected from inpatients, E. coli was the most common isolate, with a frequency of 125 (73.5%). Resistance to Nalidixic acid and fluoroquinolones, including Ciprofloxacin, Norfloxacin, and Ofloxacin, was detected in 88.8%, 71.2%, 70.4%, and 68.8% of UPEC isolates, respectively. The prevalence of hly and pap genes in FQs-R strains was significantly lower than in FQs-S strains.

 The high-level antibiotic resistance to quinolones & fluoroquinolones and heterogeneity of virulence genes among clinical UPEC isolates need strong attention.

Mycoplasma hominis is one of the smallest bacteria isolated from a natural source and is sometime as pathologic flora in plants, animals, and humans. Some of these bacteria are normal flora of the respiratory and genital systems. The aim of the study was molecular identification of M. hominis in a vaginal sample of women referred to the infertility center of Fatemieh Hospital in Hamadan.

In this Cross-sectional study, vaginal swab samples were collected from symptomatic females and M. hominis was identified by PCR and Real-Time PCR. DNA was extracted using an extraction kit. M. hominis strains were identified using 16 S rRNA gene. Finally, Statistical analysis was performed using SPSS 21 software.

A total of 234 vaginal samples were studied in women with a mean age of 39.8years. The results showed that M. hominis was identified by PCR (13%) and Real-time PCR (15%) methods, respectively. There was a significant relationship between PCR and Real-Time PCR methods (P≤0.05).

Real-time PCR assay was successfully used for rapid and accurate diagnosis of M.hominis. This method has significant potential for rapid, accurate, and is highly sensitive molecular detection of M. hominis compared to the PCR technic.

 As the most important human food source, milk and dairy products may lead to infectious diseases due to non-compliance with health standards. Brucellosis is one of the critical zoonotic diseases that affect the human population. Humans are usually infected by Brucella spp. via contaminated milk and dairy products and direct contact with infected animals.

 This study was conducted to determine the Brucella spp. contamination rate of milk and dairy products in the rural and urban areas in the city of Hamadan, west of Iran, in 2018-2019. In this descriptive-analytical study, 291 samples of nonboiling milk (227), fresh cheese (43), and cream (21) were collected from dairy products suppliers in the urban (No=103), rural areas (No=162), and industrial regions (No=26). We collected 72 samples from sheep and goats and 219 specimens from cattle. Samples were randomly selected from the target centers.

The overall contamination rate of collected samples with Brucella spp. found to be 4.1%. The milk and dairy products contamination in urban areas was 0.9%, rural 6.6%, and industrial regions 0%. Furthermore, the contamination rate varied from 9.7% to 2.5% for small ruminants and large ruminants, respectively, which was significant (P=0.01).

Given the importance of dairy consumption in the human diet and higher contamination of milk and dairy products taken from cattle, sheep, and goats with Brucella species, it is recommended that control and prevention programs in sheep and goats must be taken more seriously.

Wound infections are the primary cause of sepsis in burn wound patients and increase burn-related morbidity and mortality. Gram-negative and Gram-positive bacteria induce infections in burn wounds. Conventional antimicrobial therapy is recognized as the most successful therapeutic intervention to combat infections of burn wounds. Unfortunately, antimicrobial resistance could be catastrophic and lead to treatment failure. Burn wound infections need topical treatment. Phages as an alternative for antibiotics can be used as a monotherapy for infections with antibiotic-resistant pathogens or can be applied in combination with antibiotic therapy. Phages are species-specific bacterial natural viruses. Worldwide, many phage-producing companies are emerging. However, not many countries implement phage therapy in their patient management. Clinical trials are needed to convince the health care system in those countries that do not have confidence in phage therapy in infectious diseases. This study reviewed several aspects of phage therapy in burn wound patients.

Candida-albicans is a normal floor and one of the opportunistic pathogens in the oral cavity. There are various treatments for this infection, including nystatin. Considering the high potential of plant extracts, including green tea, in the field of antimicrobial activity, this study was designed to investigate the effect of green tea extract on Candida albicans species.

Initially, the aqueous-alcoholic extract of green tea at different concentrations was prepared. Broth micro dilution method was used to determine the MIC. From the contents of different wells containing less concentrations of green tea and no candidate growth was observed, 10 micro liter of dextrose agar substrate was removed and the lowest amount of green tea, which showed less growth was considered as minimum fungicidal concentration (MFC). Also, 50% and 100% green tea extracts of the discs were prepared to determine the size of the growth medium in the culture medium. Data analyzed using STATA software 14. 

MIC and MFC for green tea extract start at a concentration of 256 mg / ml. It was also found that the inhibition zone was equal to zero in both concentrations of 50% and 100% for the green tea extract.

It seems, green tea has antifungal effect in very high concentration rather than oral usage and also, as mouthwash and just with direct contact.

Acinetobacter baumannii is one of the causes of nosocomial infections, especially in the intensive care unit. The emergence of multidrug-resistant strains of A. baumannii has caused many problems. One of the ways to handle the phenomenon of antibiotic resistance is the use of herbal medicines and their derivatives in place of or in combination with antibiotics. The aim of this study was to investigate the effect of inhibitory effects of berberine as a barberry derivative on clinical isolates of A. baumannii, resistant to ciprofloxacin and imipenem in Hamadan hospitals.

In this study, 70 clinical isolates of A. baumannii. were identified and diagnosed using conventional microbiology. Resistance of isolates was detected against imipenem and ciprofloxacin by disk diffusion and broth microdilution method. Minimum inhibitory concentration (MIC) of berberine as well as its combined effect with antibiotics were performed using broth microdilution method.

The results of this study showed that more than 90% of isolates are resistant to ciprofloxacin and imipenem. Imipenem and ciprofloxacin MICs  were dtermined from 8 to 28  and 4 to 32 μg / mL, respectively. The berberine decreased the imipenem and ciprofloxacin MIC from zero to two fold and zero to one-fold, respectively

High level resistance to imipenem and ciprofloxacin among A.baumannii isolates is cause of concern. Berberin, in combination with imipenem and ciprofloxacin, reduces MIC to a proper level, which can be used as an effective agent to reduce antibiotic resistance in bacteria.

A study was conducted to evaluate the effects of Bacillus amyloliquefaciens on adverse effects of aflatoxin B1 in broiler chickens. A total of 480 1-d-old broiler Ross 308 (male and female) were completely randomized disgine with a 2× 2 × 2 factorial arrangements (sex and feed additives) with 4 replicates of 15 birds. Factors includes sex (male and female); probiotic (control, 108 cfu/mL B. amyloliquefaciens); aflatoxin (control, 500 AFB1 µg/kg), Performance, the activity of liver enzymes, immune and some blood parameters were not affected by sex (p> 0.05). Body weight and feed intake of aflatoxin B1 group were significantly decreased compared other (p< 0.05). There was no significantly drffenece in feed conversion ratio compared with other groups during total period (p>0.05). Activity of liver enzymes including aspartate amino transferase, alanine amino transferase, alkaline phosphatase and lactate dehydrogenase were significantly increased in aflatoxin B1 group (p<0.05). The counts of red blood cells and withe blood cells, hematocrite and hemoglobin percentages were significantly decreased in aflatoxin B1 group compared with other (p<0.05). The aflatoxin B1 group has shown the lowest of antibody production against newcastle disease and sheep blood red cell also, the lowest of skin thickness in responding to phytohaemagglutinin (p<0.05). In conclusion, the supplementation of B. amyloliquefaciens to contaminated food could be improved performance and increased the activity of liver enzyme and immune response in broilers.

Urinary tract infection is the second most common cause of infection in the human body. Among the causes of urinary tract infection, Escherichia coli is the most common bacteria causing the urinary tract infection in both genders (male and female). Therefore, the aim of this study was to determine the antibiotic resistance pattern of bacteria causing urinary tract infection in the urine culture samples of the Shahid Beheshti Hospital Laboratory in Hamadan during 2016-2017. This descriptive cross-sectional study was conducted based on a purposive sampling for 16 months from April 2016 to July 2017 in Shahid Beheshti Hospital, Hamadan. In this study, urine specimens were collected by Midstream Clean Sugar method and then cultured in two Blood Agar and EMB culture mediums using standard loop. The results showed that, out of 1400 urine samples from outpatients referring to Shahid Beheshti Hospital in Hamadan, 235 were positive, of which 105 cases (44.7%) were related to men and 130 cases (55.4%) were women. Escherichia coli isolated with 141 (60%) cases was the most common organisms. Most of Escherichia coli isolates (126 cases) were resistant to ciprofloxacin antibiotic and only 1 case of resistance to Carbenicillin was observed. In general, the results showed that the most common bacterial agent of urinary tract infection was Escherichia coli and the highest cases of this isolate were resistance to ciprofloxacin. In addition, the highest antibiotic susceptibility was related to Nitrofurantoin.

Pharmaceutical residuals like antibiotics in livestock products and their consumption by humans from food chain can lead to the spread of bacteria resistant to antibiotics. The aim of the current study was to investigate antibiotic resistance and determine the prevalence rate of genes encoding extended spectrum beta-lactamase (ESBLs) in Acinetobacter strains isolated from raw foodstuffs. In this study, 300 samples from protein foodstuffs (mutton, beef, chicken, hamburger, hot dog, sausages) and dairy foodstuffs (raw milk and cheese) were prepared and investigated in terms of contamination with Acinetobacter baumannii from July 2015 to November 2016. The isolated bacteria were identified by biochemical tests to species level and confirmed by the PCR technique via blaOXA-51 gene. Antibiotic resistance of the isolates was studied using the diffusion disc method. Also, the presence of ESBLs enzymes in the isolates wa s done phenotypically and genetically through PCR and combined disk tests. The results showed that 43 strains of A. baumannii were isolated from the protein and dairy foodstuffs, 93% from protein foodstuffs and 7% from dairy foodstuffs. Also, 30% of the isolates had multidrug- resistance (MDR). Further, the findings of PCR illustrated that the prevalence of genes encoding ESBLs in the isolates were: TEM 21%, PER 23.5%, VEB 18.5 % and SHV35%. Foodstuffs can act as a food source for A. baumannii that can lead to transferring and spreading genes encoding antibiotic resistance to humans.

  Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli are the most important bacteria responsible for hospital infections with multiple antibiotic resistance. Problems in the treatment of infections caused by resistant isolates have been the factor for the investigation of alternative drugs, including medicinal plants. In this experimental study, antimicrobial activity of aqueous and alcoholic extract of Garlic and Aloe vera on 63 strains of P. aeruginosa, S. aureus and E. coli isolated from clinical specimens were investigated. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) was carried out by tube dilution method.
Results and In the MIC test, E. coli isolates showed the most sensitivity to the aqueous (with mean MIC, MBC 236.8 and 473.6 mg/ml, respectively) and alcoholic extract of the Garlic (with mean MIC, MBC 329.6 and 659.2 mg/ml, respectively) (P<0.05). Clinical isolates of S. aureus showed the highest susceptibility to garlic alcoholic extract, followed by aqueous extract of garlic and alcoholic extract of aloe vera (with mean MIC, 156.8, 188.8 and 198.4 mg/ml, respectively). The results showed that the isolates of P. aeruginosa were resistant to both garlic and aloe vera extracts.
Considering the significant antibacterial effects of alcoholic and aqueous extracts of garlic and alcoholic extract of aloe vera on pathogenic bacteria, that contribute to the development of various types of infectious and nosocomial infections, these extracts can be considered as natural and alternative drugs

AmpC-type beta-lactamases have been implicated in group C of Amber, which includes EBC, CIT, MOX, FOX, DHA, and ACC. The active presence of these plasmid genes in clinical isolates of P.aeruginosa has resulted in resistance to a wide range of antibiotics. Therefore, we aimed to determine the minimum inhibitory concentrations (MIC) of different antibiotic groups in clinical isolates of P. aeruginosa carrying AmpC enzyme and study their relationship pattern.
In this descriptive study, the MIC of 95 P. aeruginosa isolates was determined using E-test for cefocytosine, cefpodoxime, cefotaxime, ceftazidime, ciprofloxacin, colicitin, aztreonam, and ceftriaxone antibiotics (Liofilchem, Italy). Multiplex polymerase chain reaction was used to amplify and identify plasmid genes. The Chi-squared test was used to determine the relationship between variables.
Of the 95 P. aeruginosa isolates, 95 (100%) isolates were resistant to cefoxitin, 79 (83.5%) isolates to cefpodoxime, 2 (2.1%) isolates to ceftazidime, 87 (81.57%) isolates to ceftriaxone, and 22 (23.15%) isolates were resistant to aterranum, but none of the isolates was resistant to colistin. In addition, 21 (22.1%) isolates had FOX gene, 13 (11.57%) isolates had AAC gene, 7 (36.6%) isolates had MOX gene, 4 (21.4%) isolates had CIT gene, 2 (2.1%) isolates had DHA gene, and 1 (1.05%) isolate had EBC gene. It is worth mentioning that there was a significant relationship between the presence of plasmid genes and antibiotic resistance (level of significance: P≤0.05).
The presence of the genes encoding the AmpC enzyme can provide the ground for resistance to a broad range of antibiotics.

Today, due to the occurrence of drug resistance and the ability of bacteria to develop acute infections, investigating the antimicrobial effects of herbs has been proposed. Therefore, we aimed to examine the effects of Hypericum perforatum extract and microemulsion and Aloe vera extract on Brucella bacteria.
This experimental study was carried out with the help of a hood in a biosafety level 2 laboratory. Fifty blood serum samples were cultured in BACTEC for brucellosis, and if grown, they were transferred to Brucella Agar in an anaerojar containing 10-5% CO2 for 48-72 h. Biochemical validation tests were carried out on the grown samples. Extraction was performed by a reflux (distillation) apparatus in a 1 liter balloon and a 40 cm spiral arm. Microemulsion structure was prepared by emulsifiers from the extract. Afterwards, 1, 8.4, and 2 mg/L dilutions of the aqueous extracts of Hypericum perforatum and Aloe vera were prepared, and the antimicrobial properties of these extracts were evaluated by disc diffusion, pour plate, and extraction methods on pure culture of Brucella isolated from patients.
Evaluation of antimicrobial effects on the isolated Brucella strains showed that the mean diameters of the zones of inhibition in the studied strains for the of 8-1 mg/l concentrations of Hypericum perforatum extract were 36.6±2 and 18±3 mm, respectively, and for Aloe vera they were respectively 30.7±3 and 18±1 mm. None of the strains formed an inhibition zone at the 0.5 mg/l concentration. Evaluation of the effect of the extract in the well diffusion method also yielded similar results, but in the pour plate method, the effect of the extractes on the bacteria was not observed. Micoemulsion of the Hypericum perforatum extract did not have any effect because of over dilution.
The disk diffusion method under biosafety level 2 laboratory was highly effective, and the extract of Hypericum perforatum had the highest effect on Brucella; therefore, it is recommended for clinical studies.

Different clinical specimens play a decisive role in the type and nature of drug resistance in pathogenic organisms. Occasionally, the presence of certain antibiotic resistance genes is associated with the type of clinical specimen. The aim of this study was to determine the relationship between the presence of chromosomal and plasmid-encoded AmpC genes and type of clinical specimen in Pseudomonas aeruginosa.
In this descriptive and experimental study, 114 isolates of Pseudomonas aeruginosa, and clinical specimens including blood, urine, wound secretion, burn injuries were collected from teaching hospitals in Hamadan. The presence of chromosomal and plasmid-encoded AmpC genes was evaluated using multiplex PCR technique.
FINDINGS: The plasmid-encoded AmpC genes were observed more than chromosomal genes in Pseudomonas aeruginosa isolates. The FOX gene with a value of 29 (37.66%) (p≤0.037) and DHA gene with a value of 5(6.4%) (p≤0.015) in plasmid-encoded AmpC genes, while FOX gene with a value of 39 (48.75%) (p≤0.001) and MOX gene with a value of 2 (7.36%) in chromosomal AmpC genes had the highest and lowest frequency, respectively.
The results of the study showed that the presence of chromosomal and plasmid-encoded AmpC genes may have various frequencies according to the type of clinical specimen.

The Mycoplasma Hominis bacterium lives on in the female reproductive system. Recent studies have shown that the presence of this bacterium is associated with disorders such as vaginosis, infertility, abortion and preterm labor. This study was performed with aim to determine the frequency of Mycoplasma hominis in women referred to Infertility Clinic of Hamadan Fatemieh Hospital.
This epidemiologic-descriptive study was performed on 234 patients referred to the infertility clinic of Hamadan Fatemieh Hospital in 2016. Screening was performed using swabs from the endocervix of 234 female patients who had at least one of the symptoms of vaginosis, infertility, abortion and preterm labor. The culture medium was removed by filtration and the PCR molecular technique was used to trace the 16s rRNA gene as two methods for detection of bacteria. Data was analyzed by SPSS software and McNemar's test. P The frequency of Mycoplasma hominis in both methods was 13.7%. The correlation coefficient between culture and PCR methods was relatively desirable for detection of this bacterium (k=0.5). 41 patients (24.4%) with history of at least one abortion and 148 (14.2%) with vaginosis were diagnosed as positive Mycoplasma agar. The highest prevalence of Mycoplasma hominis was observed in the age range of 30-39 years.
Although the PCR molecular technique has high sensitivity to diagnose Mycoplasma hominis, but the modified culture method has an acceptable sensitivity to detect this bacterium.

Resistance to methicillin and the presence of the ccr gene in Staphylococcus aureus have provided the basis for the emergence of methicillin resistant strains. The aim of this study was to identify the ccr cassette alleles in methicillin-resistant S.aureus strains and to determine the relationship between the presence of these casts with a multivariate process.
In this study, 135 clinical isolates of methicillin-resistant S.aureus was isolated by genotypic methods. ccr gene cassette was evaluated qualitatively by multiplex PCR method. Data was analyzed using SPSS version 16 and also, the chi - square test was used.
FINDINGS: Out of 135 strains of S.aureus resistant to methicillin, penicillin and erythromycin antibiotic resistance were the most frequent, more than 90%, respectively. Also, ccr gene cassette in the study on genes ccrA/B1, ccrA/B2, ccrA/B3, ccrA/B4, ccrA2/B, ccrC had taken place, respectively, in 2 isolates (1.3%) for gene ccrA/B1, 12 isolates (8.2%) ccrA/B2, 15 isolates (10.34 %) ccrA/B3, 2 isolates (1.3%) ccrA/B4, 4 isolates (8.2 percent) ccrA2/B and 22 isolates (15.87 %) were positive for the gene ccrC. A significant correlation between the presence of these genes and antibiotic distribution was observed (p=0.05).
The ccr gene cassette can provide a background of resistance to various antibiotics in methicillin-resistant S.aureus strains.

Campylobacter is a common type of bacteria in humans and poultry, which generally accounts for various diseases in humans, such as gastroenteritis. The poultry digestive system contains a high level of these bacteria. The aim of this study was to evaluate the prevalence of C. jejuni and C. coli in the poultry liver packed for marketing and determine the antibiotic resistance of the isolates.
This cross-sectional study was conducted in the spring of 2016 in the city of Hamadan, Iran. A total of 80 samples of packed chicken liver were collected from the stores supplying meat and poultry products in Hamadan. The enrichment of the liver samples was performed in brucella broth; subsequently, separation was carried out on Campylobacter selective agar. The presence of bacteria was confirmed by the implementation of chemical diagnostic tests and direct microscopic observation. Finally, the antibiotic resistance of the isolates was tested using disk diffusion method.
According to the results, Campylobacter had a prevalence rate of 90%, 73.61% and 26.39% of which were C. jejuni and C. coli, respectively. Out of the 12 antibiotic discs used in this study, the highest resistance (79%) and sensitivity (99%) rates were observed for cotrimoxazole (10 µg) and gentamycin (10 µg), respectively.
The packed poultry liver in Hamadan had a relatively high prevalence of C. jejuni and C. coli. Therefore, the consumers should be careful about the cooking time and using this food. Accordingly, they can prevent the dissemination of this bacteria by cooking the liver at a temperature of above 70°C for 20 min and properly washing the devices before cooking this product. Additionally, the elderly, children, and those with immunodeficiency are recommended to avoid eating poultry liver.

Rapid and timely detection of Staphylococcus aureus can play a significant role in the treatment of staphylococcal infections.Impresingly, by precise designing methods which have acceptable sensitivity and specificity, can identify species and even antibiotic-resistant strains. The purpose of this study was to evaluate the real time PCR diagnostic method based on the melting curve analysis for the detection of clinical isolates of S. aureus and the methicilin resistance gene.
In this experimental study, clinical isolated of S. aureus was used from the Microbiology Bank of Hamadan University of Medical Sciences. The primer design was done by selecting (ITS) target for S. aureus and the mecA gene for methicillin-resistant strains. Real-time PCR and DNA melting curves analysis were used to determine the analytical specificity and sensitivity of the designed primers.
The analytical specificity of the primers was 83.79 ° C for S. aureus and 76.6 ° C for methicillin resistant Staphylococcus aureus respectively. The analytical sensitivity of the primers was 15 CFU/ml bacteria for ITS gene and 25 CFU/ml bacteria for mecA gene.
By selecting appropriate primers and using sensitive molecular techniques, which could be the main factors for designing of both quick and accurate method, it is possible to identify invasive bacteria such as S. aureus.

Pseudomonas aeruginosa is one of the most important reasons of morbidity and mortality due to infections in hospitals. The biochemical methods to detect Pseudomonas aeruginosa are time consuming, therefore, the objective of this study was to evaluate the ability of Multiplex-PCR method in the detection of Pseudomonas aeruginosa. Multiplex PCR optimizing and evaluation of its specificity and sensitivity was performed using three specific genes of Pseudomonas aeruginosa (oprL, oprI, and 16s rDNA). PCR products 256,172 and 956 bp were amplified by primers. To make sure the amplified fragment are specific products of related genes , negative control with no DNA samples were included which didn’t show any amplification. This method has a sensitivity of 80 copies of target DNA and using the DNA samples of other organisms, undesired applicant was not observed. Multiplex PCR is a faster method than biochemical tests and also due to the use of three genes provides a reliable method to identify Pseudomonas aeruginosa.

In recent years, the role of integrons has been identified in the transfer of antibiotic resistance genes. The aim of this study was to determine the antibiotic resistance pattern and to identify class I and II integrons and associated gene cassettes in clinical isolates of methicillin-resistant Staphylococcus aureus.
In this descriptive cross-sectional study, 100 isolates of S. aureus were isolated from clinical samples in 2015. After cultivation, the isolates were verified by standard biochemical tests. Then, PCR test was used on nuc gene for final confirmation of the isolates and presence of methicillin-resistance gene. Then, methicillin-resistant isolates were tested for susceptibility to 9 antibiotics. Finally, identification of Class I and II integrons genes and associated gene cassettes was performed on mecA gene using PCR method. Data analysis was carried out using Chi square test.
Forty-one out of 100 S. aureus isolates carried mecA gene. The most frequent antibiotic resistance was for cefoxitin and tetracycline (41 and 36 isolates, respectively) and the lowest resistance was reported for vancomycin (0). In this study, The prevalence of 38 isolates (92.68%) and 3 isolates (7.31%) produced class I and II integrons. One type of gene cassette was identified in these isolates, which was related to aadA1 gene cassette.
The results of the current study were indicative of high prevalence of antibiotic resistance and class I integrons in S. aureus isolates carrying mecA gene.

Implementing orthodontic treatment can cause severe caries in teeth in the shape of light spot. The present study planned to evaluate the ability of green tea varnish in the prevention of caries caused by fixed orthodontic.
In the present experimental study, a total number of 45 premolar healthy teeth were selected and categorized into 3 equal groups (N=15) after placing brackets on them. Group 1 (control group): after placing brackets, teeth received no treatment. Group 2: green tea varnish was applied around the brackets in 48 hours intervals for a 21 days period of time. Group 3: green tea varnish was applied around the brackets in 24 hours intervals for a 21 days period of time. After this period, the 40 Micron sections were prepared cervical than the location of the brackets in order to study the avarage of caries depth in micrometers using polarized light in three points at a distance of 500 Micron from each other. The measurment data were analyzed by the SPSS 16.0 software using Kruskal-Wallis and Mann-Whitney nonparametric statistical tests. A significance level of 0.05% was considered.
The average and standard deviation of the caries depth in groups 1, 2, and 3 is 452.03±290.72, 44.91±92.92 and zero respectively. The control group have the most caries depths compared to other groups. Results of groups 1 and 2 had no significant differenc (P=0.878); but, the groups 1 and 2 and also grous 1 and 3 had significant difference with each other (P The results of this study showed that the utilization of green tea varnish in 21-day period at 24 and 48 hours intervals reduces tooth caries around the orthodontic brackets.

Background and Brucellosis is a zoonotic disease. Given that serologic test has some specific characteristics such as difficult growth, problems associated with culture, and cross-reactions with otherbacteria, in this study multiplex real-time polymerase chain reaction (PCR) method was used to detect the most common species of Brucella spp.
This experimental study was performed in Hamedan University of Medical Sciences, Hamedan, Iran, 2015, in two bioinformatical and analytical stages. A universal primer was designed to detect Brucella genus and two primers were prepared for B. melitensis and B. abortus, which are the most common species. The target genes for universal Brucella, B. melitensis, and B. abortus primers were ITS, BMEII-0466, and BruAB2-0168, respectively. In the analytical stage, specificity and sensitivity of the primers were evaluated.
In this study, the universal primer of Brucella was detected in 83 bp at melt temperature of 82∘C. Moreover, B. melitensis and B. abortus primers were specifically identified in 121 bp and 285 bp at melt tempretures of 84∘C and 87∘C, respectively. The sensitivity for the universal Brucella primer and B. abortus was 50 fg, while it was 100 fg for the B. melitensis primer.
The identified primers revealed high levels of sensitivity and specificity. Therefore, they can be considered along with culture in clinical trials.

To date, surgery has been the treatment of choice for hydatid cyst, with regard to danger of leakage of hydatid cyst contents into viscera and production of secondary cysts, after spread of protoscolices. Different scolicidal agents get injected into cyst for preventing the secondary cyst production, which may cause different side effects in host, especially in the surrounding tissues. In this research, the scolicidal effects of bacterial extract isolated from infected hydatid cyst was evaluated.
In this experimental-laboratorial study, at first, isolation and identification of the infecting bacteria of hydatid cyst were performed at the level of species. Then, total the bacterial extract was prepared by sonication method, and serial dilutions (1.1, 1.2, 1.4, 1.8, 1.16, 1.32 and 1.64) were prepared using sterile saline as the solvent. The obtained alive larvae at the times of 5, 10, 20, 40 and 60 minutes were placed in those dilutions and mean of dead protoscoleces were determined using eosin exclusive staining method.
The identified bacteria isolated from the infected hydatid cysts were as follows: E. coli, Staphylococcus aureus, S. saprophyticus, Proteus mirabilis and Pseudomonas aeruginosa. The extract of isolated bacteria at the mentioned times had no considerable scolicidal effects. For example, the whole extract of P. aeruginosa after 60 minutes of exposure showed a maximum of 13.17%. scolicidal effect.
The results of this study showed low scolicidal effect of bacterial extracts isolated from hydatid cyst. Degeneration of scolices in infected cysts can be due to other reasons than bacterial extract.

Selecting efficient disinfectants and use standard disinfectant methods can be effective in reducing nosocomial infections.
In this study samples were collected from different parts of social security hospitals randomly¡ bacteria causing hospital infection including Staphylococcus Aureus¡ Staphylococcus epidermidis¡ Pseudo-monas aerogenes¡ and E. coli were isolated. The effect of various parameters including minimum inhibitory concentration¡ minimum bactericidal concentration¡ and diameter of bacterial growth inhibition zone of the pit and disk was evaluated.
The results showed Sayaspt IH¡ HP¡ Astranyvs¡ and Sayaspt in terms of sensitivity to antimicro-bial agent (the diameter of inhibition zone around the disc and in the pit) were very efficient¡ respectively¡ While Percidine (1%) was relatively weak. In this study¡ Sayaspt IH and Percidine had a suitable efficiency.
In accordance with the results Sayaspt IH¡ Sayaspt HP and Astranyvs were efficient¡ while Percidine was relatively weak. Therefore¡ these compounds can be used as strong and effective disinfect-ants in hospital setting.Keywords:

Multidrug-resistant bacteria make many problems in clinical therapy, design and manufacture of synthetic drugs. Pseudomonas aeruginosa is one of the most important multidrug-resistance bacteria leads to variety infections in human especially in immunocompromised, patients with severe burns, and nosocomial infections. It Recent years, this organism makes a big challenge in clinical treatment of infections using a wide range of antibiotics. Medicinal herbs for thousands of years to prevent or treat infectious diseases were considered. Today, pharmacists have high interest of using medicinal herbs to prepare a new antimicrobial compounds. The goal of this study was to investigation the effect of aqueous and alcoholic extract of fresh garlic on the expression of genes encoding elastase and exotoxin A virulence factors, in P. aeruginosa PAO1 strain.
Present study was an experimental study and performed from 2015 to 2016 in Hamadan University of Medical Science, Iran. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of aqueous and alcoholic extract of garlic was determined. Then in order to investigation the gene expression of elastase and exotoxin A genes, quantitative real-time polymerase chain reaction (qPCR) method was performed at sub-MBC concentrations.
According to the results aqueous extracts of garlic had better impact in comparison with alcoholic alone. At concentration of 64 and 8 mg/ml of aqueous extract the expression of both elastase and exotoxin A genes were decreased. Although, the expression of elastase gene was most affected by garlic at different concentrations than exotoxin A.
The results suggested that the compositions of garlic extracts can inhibit the production of virulence factors in P. aeruginosa. So in order to treat infectious diseases in the near future, medicinal plants known as new antimicrobial drugs can be used alone or with antibiotic drugs against pathogenic bacteria.

Identification of sulfur-degrading microorganisms is a major step in microbial desulfurization of organic compounds, especially oil. Microbial desulphurization is ecologically safe and economically justifiable; hence, the importance of knowledge on the identification, isolation, and adaptation of microorganisms from operational, economic, and environmental viewpoints. The objective of this descriptive‒applied research was to identify and isolate sulfur-degrading bacteria in the sludge from Tehran refinery wastewater treatment plant. For this purpose, 120 samples (10 samples per month over a 12‒month period) were collected from different locations and elevations of the sedimentation basin. The samples were then stirred and homogenized before they were transferred to the laboratory where they were cultured on specific and differential media to allow the microorganisms to grow. Finally, tests were performed and the following bacteria were identified in the samples: Brevundiomonas vesicularis, Acinetobacter spp, Clostridium spp, Alcaligenes spp, E.coli, Bacillus spp, Klebsiella spp, Acromobacter spp, and Desulfovibrio spp. Results indicate that all the bacteria identified in the samples used sulfur as their only source of energy. Another important contribution of this study is that Brevundiomonas vesicularis is for the first time identified in this study as a sulfur-degrading one.