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Background: Microbial infections are important challenges to health, and health care officials have major difficulties dealing with them especially regarding their antibiotic resistance. The main aim of this study was to evaluate drug synergistic and anti-bacterial effects of cuminum cyminum essential oil on some pathogen bacteria. Materials and Methods: Cuminum cyminum essential oil was extracted from its fruit. For evaluation of antibacterial effects of the essential oil, disc diffusion method through the measurement of the inhibitory zone diameter and micro-broth dilution for determining the minimum inhibitory concentration (MIC) on several standard bacteria were used. In evaluation of the synergistic and antagonistic effects, standard bacteria were cultured in the media containing essential oil, and antibiotic discs were, then, placed on it. Results: According to the results of disc diffusion test in Agar, cuminum cyminum essential oil, with a 44 mm inhibition zone, had the greatest antibacterial activity against bacillus cereus. It had the greatest positive co-action with gentamicin (10 µg) on escherichia coli. Conclusion: The results of this study indicate that cuminum cyminum essential oil alone or in combination with antimicrobial agents may be useful in treatment of bacterial infections. Additionally, this component can enhance the effect of some antibiotics this implies its application, especially in drug resistance cases.

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Background: Pseudomonas aeruginosa is one of the most important causes of nosocomial infection which due to extended spectrum-beta lactamases (ESBLs) and metallo-beta lactamase (MBL) producing strains is resistant to a wide range of antibiotics. The aim of this study was to detect ESBL and MBL producing P.aeruginosa isolated from patients and investigate the effects of methanol extracts of Zataria multiflora, Myrtus communis, and Peganum harmala on them. Materials and Methods: In this experimental study, samples were obtained from 245 patients, referring to Shafa Hospital, Kerman, Iran. ESBLs producing strains were detected by double disk synergy test and phenotypic confirmatory test. In addition, E-test strips were used for MBL detection. P.aeruginosa MIC was determined for cefotaxime, ceftazidime, azteronam, imipenem, and meropenem. Methanol extracts of Zataria multiflora, Peganum harmala, and Myrtus communis plants were prepared by Agar perculation method. Results: Out of 245 patients referring to the burn unit, 120 P.aeruginosa isolates were detected from which 41 contained ESBL but they lacked MBL. 60% of isolates were resistant to cefotaxime, 66% to ceftazidime, 42% to azteronam, 3% to imipenem, and 5% to meropenem. Among the extracts, Zataria multiflora had the highest antibacterial effect on standard strains of P.aeruginosa in comparison with Peganum harmala and Myrtus communis. Conclusion: The prevalence of ESBL producing P.aeruginosa strains is high. In addition, noticing their high antibiotic resistance, utilization of herbs, such as Zataria multiflora may be considered an appropriate alternative for treatment however, more investigations are needed.

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Background: The major aim of this study was synthesis and assay of antimicrobial activity of peptide D28 and its new analogues derivatives as dimeric peptides. Materials and Methods: Three antimicrobial peptides known as D28, Di-D28-Lys,Di-Cys-D28 including 20, 41, 42 residues were synthesized respectively. For peptide synthesis, solid phase peptide synthesis method using blocked amino acids with flourenyl methoxy carbonyl group and for peptide purification HPLC were used. Peptides compositions were confirmed by amino acid analysis and SDS-PAGE electrophoresis. Antimicrobial tests against Staphylococcus aureus and Pseudomonas aeruginosa were performed as disk and well diffusion on plate and by adding to liquid broth culture (Broth macrodilution) in different concentrations. Results: Three required peptides (D28, Di-D28-Lys, Di-Cys-D28) successfully were synthesized. All three peptides were effective against S. aureus, but Di-Cys-D28 on the contrary to two other ones, showed no antimicrobial activity against P. aeruginosa. The inhibitory activity of Di-D28-Lys against P. aeruginosa was more than that of D28 peptide. Conclusion: Improvement of antimicrobial peptides activity through dimerization depends on the methods of dimerization and the strain of bacterium. Di-D28-Lys peptide in comparison with D28 and Di-Cys-D28 showed wide range and more antimicrobial activity. Therefore, Di-D28-Lys peptide could be a suitable antibiotic candidate for future studies.

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Human Brucellosis is an infectious disease caused by Brucella bacteria. An average of 150 cases of brucellosis among 330 million people is reported in the USA each year. This bacterium is small, gram-negative rods that grow in phagocytes. They primarily cause diseases among different animals and humans become infected when is in contact with animals or their products. Brucella can cause various symptoms in humans which is similar to human influenza. Brucellosis is diagnosed in a laboratory by finding Brucella organisms in samples of blood or bone marrow or to detect antibodies against the bacteria in two blood samples, collected 2 weeks apart. Depending on severity of illness, recovery may take as long as several months. There is no vaccine available for human except live vaccines and that should be consulted to a health care provider. DNA findings for Brucella species in the index patients focused our attention on revealed human cancers. Also, granalomatous inflammation of testes and medulloblastomas has been linked to chronic Brucellosis infection which could be similar to Helicobacter pylori that is associated with gastric tumor formation. More scientific investigation is needed to properly address the connection of Brucella with other human malignancies.

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Background: Conjunctivitis is a common cause of reference to pediatrician and general hospitals. The common method of treatment is prescription of antibiotics however, there are concerns over the development of antibiotics resistance and their adverse effects. Therefore, this study was done to compare the effects of boiled water as supplementary treatment and antibiotics on the severity of infants' conjunctivitis. Materials and Methods: In this clinical trial, 110 infants referring to the Pediatric Clinic of Amir Kabir Hospital in Arak were randomly allocated to 2 groups. The first group (intervention) received boiled water together with ophthalmic erythromycin ointment 1% and sulfastamid ophthalmic solution 10% four times a day and the second group (control) just received antibiotics. Severity of infants conjunctivitis on the first, third, and seventh days of treatment were compared between the two groups using SPSS software. Results: On the 3rd day, 18.2% of the infants in the intervention group and 9.1% of the infants in the antibiotics group were cured which did not indicate a significant difference (p=0.44). On the 7th day, the recovery rate was promoted to 32.7% and 34.5% in the intervention and control groups, respectively (p>0.05). Mild severity cases were 58.2% in the intervention and 45.5% in the control groups (p>0.05) while moderate severity cases of conjunctivitis were 9.1% and 20% in the intervention and control groups, respectively (p>0.05). Conclusion: Although the number of infants who were cured was more in the boiled water group with antibiotics group and the intensity and duration of their disease were less than the control group, these differences were not statistically significant.

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Background: Pseudomonas aeruginosa is a human opportunistic pathogen which is considered one of the agents causing nosocamial infection. Recent studies have reported increased resistance of Pseudomonas aeruginosa to imipenem. The aim of this study was to determine resistance to antipseudomonal antibiotics including imipenem in Pseudomonas aeruginosa strains. Materials and Methods: In this cross-sectional study, 100 Pseudomonas aeruginosa strains obtained from clinical samples of patients in hospitals in Arak, Iran, were identified and isolated through microbiological methods, including Gram staining, oxidase test, Indol test, and oxidative-fermentative test. Then antibiotic susceptibility test was performed for imipenem, meropenem, gentamicin, amikacin, ciprofloxacin, and ceftazidime by disk diffusion method according to NCCLS (National Committee for Clinical Laboratory Standards) .Minimum inhibitory concentration (MIC) was done for determining imipenem-resistant strains Results: Antibiotic susceptibility test showed that resistance rates to imipenem, meropenem, gentamicin, amikacin, ciprofloxacin, and ceftazidime were 35%, 35%, 14%, 9%, 23% and 15%, respectively. Also, MIC test showed that 30 strains were resistant to imipenem, 27 to ceftazidime, 35 to cefepime, and 35 to ciprofloxacin. Conclusion: The results of this study indicated a high rate of antibiotics resistant of Pseudomonas aeroginosa strains to different antibiotic groups. Therefore, new and more effective methods should be found for controlling Pseudomonas infections and preventing the outbreak of its antibiotic-resistant strains.

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Background: Enterococcus is known as an important pathogen in Iran like all around the world. The increasing use of vancomycin makes vancomycin-resistant enterococci (VRE) an important nosocomial pathogen. Vancomycin in combination with an aminoglycoside can provide effective treatment for severe enterococcus infections, while resistance to vancomycin antibiotic is increasing in enterococci. In this study, the pattern of antibiotic resistance and prevalence of vancomycin resistance enterococci have been explored. Materials and Methods: In this experimental study, after isolating and identifying 150 strains of enterococci from clinical specimens, the antibiotic resistance pattern of these strains to erythromycin, teicoplanin, vancomycin, ciprofloxacin, tetracycline, gentamicin, co-trimoxazole and linezolid was examined. The MIC test by using micro dilution broth method was performed for the vancomycin resistance enterococci specimens with the vancomycin and teicoplanin antibiotics. Results: Antibiotic susceptibility test showed 14% and 5.3% of the samples were resistant to vancomycin and teicoplanin respectively. Resistant to erythromycin, co-trimoxazole, ciprofloxacin, tetracycline, linezolid and gentamicin were 64, 40, 38.6, 6.6, 0, 38.76 percent respectively. Fourteen samples had high resistance to vancomycin which MIC were ≥ 256 µg/ml. Conclusion: Based on the results of present study, there are vancomycin-resistant enterococci in Arak as well as other parts of the world. The percentage of vancomycin resistance enterococci is high in Arak and appropriate treatment of infections caused by enterococcus is essential

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Background: Nowadays, international concern about the impact of antibiotic residues on the environment increased and their removal has received a lot of consideration. The aim of this study was to investigate the efficiency of Fenton’s advanced oxidation process (H2O2/Fe+2) in sulfadiazine antibiotic removal from aqueous solutions. Materials and Methods: An experimental-laboratory scale study was done on a synthetic wastewater containing sulfadiazine antibiotic with 0.079, 0.19, and 0.47 mM concentrations under Fenton’s process. Then optimal values of affecting parameters, such as initial antibiotic concentration, molar ratio of reagents, [Fe+2] and [H2O2] concentration, detention time, and pH, were determined. The discharged effluent analyzed by HPLC-UV to identify the antibiotic residues. Results: The results showed that the optimal parameters in the Fenton’s oxidation process to remove the sulfadiazine included antibiotics at pH 3.5, molar ratio of [H2O2] / [Fe +2] equal to 1.5, and contact time of 15 minutes, respectively. In these optimal conditions, the efficiency of removal of antibiotic in concentrations of 0.079, 0.19, and 0.47 mM were 99.82%, 97.97% and 78.23% and the wastewater COD removal degrees were 83.33%, 78.57%, and 78.57%, respectively. Conclusion: The experiments showed the efficient removal of sulfadiazine antibiotic in wastewater by Fenton’s oxidation process. The efficiency of this method can also be considered in eliminating other antibiotics resistant to biological treatment

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Background: Staphylococcus aureus is considered a common pathogenic factor in infections. Increase in infections caused by this bacterium in developing countries has led to many problems. The aim of this study is to identify the antibiotic patterns of methicillin-resistant Staphylococcus aureus isolated from patients in the central hospital of Arak.

Materials and Methods: In this descriptive cross-sectional study, a total of 100 samples were isolated from hospital patients during one year. The isolates sensitivity to cefoxitin and oxacilin disks were evaluated through disk diffusion. Using polymerase chain reaction (PCR), the isolates were tested for the presence of mecA gene. Finally, antibacterial resistance patterns of the isolates to 13 antibiotics were determined.

Results: In this study, 80 samples in a total of 100 isolates of Staphylococcus aureus were methicillin-resistant. Evaluation and assessment of antibiotic resistance showed the greatest resistance to penicillin (100%), tetracycline (88.50%), levofloxacin (85.70%), and ciprofloxacin (85.70%), respectively, while the lowest levels of resistance were observed to antibiotics chloramphenicol (5.70%), netilmicin (5.70%), and mupirocin (0%), respectively.

Conclusion: This study showed increased resistance to different antibiotics in Staphylococcus aureus that is a serious warning to the treatment of infections caused by this bacterium in the region. Therefore, in order to prevent increased resistance to other antibiotics, it is essential to withhold prescriptions and unessential use of available antibiotics.

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Background: The overuse of therapeutic antibiotics results in the drug resistance. The excessive use of antibiotics causes the mutations in the microorganisms and the emergence of new microorganisms which are resistant against the common antibiotics. With regard to limitations and known side effects of antibiotics, the exploring of antimicrobial compounds seems necessary. The purpose of this study is to evaluate the antimicrobial effects of aqueous and ethanolic extracts of Chevil against Staphylococcus epidermidis PTCC 1435, Yersinia enterocolitica PTCC 1221 and Enterobacter aeruginosa PTCC 1151 and to compare them with the common therapeutic antibiotics.

Materials and Methods: In this experimental study, after collecting plants from the highlands of Chaharmahal va Bakhtiari province, the extraction was carried out by the maceration method. To evaluate the antimicrobial activity, Disc diffusion test with Kirby-Bauer method was used. The Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentration (MBC) were determined by using the dilution method.

Results: The highest inhibition zone diameter in 40 mg/ml was related to Staphylococcus epidermidis and the minimum diameter in this concentration was related to Gram-negative bacteria, Enterobacter aeruginosa. MIC of aqueous and ethanolic extracts for Enterobacter aeruginosa 64 and 32 mg/ml and MBC of ethanolic and aqueous extracts of Enterobacter aeruginosa were 128 and 64 mg/ml respectively.

Conclusion: The ethanolic extract of the Chevil compared with the common therapeutic antibiotics had more inhibitory effect on studied bacteria. Furthermore, Chevil extracts showed greater inhibitory effect on Gram-positive bacteria in comparison with Gram-negative bacteria.

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Background: Drugs residual discharge into the environment through municipal and hospital wastewaters is one of the emergent environmental problems. Imipenem as a professional hospital antibiotic is widely used against gram- positive and negative bacteria and with entrance to the aquatic environments could prompt a lot of risks such as bacteria resistance, allergies, spoiling alga and daphnia and interrupting in wastewater treatment processes. Therefore there is a command to develop a method for extraction and determination of Imipenem from hospital sewage.

Materials and Methods: Solid phase extraction (SPE) was used to extract Imipenem from samples. Recovery percentage calculated at different pH of 3 and 7. The extracted samples analyzed by High Performance Liquid Chromatography (HPLC) equipped with UV detector. HPLC operated using borate buffer/methanol as mobile phase at flow rate of 0.7 ml/min, column temperature of 20 °C, and UV wavelength of 280-300 nm.

Results: Maximum recovery percentage was obtained 68% at pH=7. The best condition for HPLC was 80:20 ratio of borate buffer/methanol with pH=7.5 and at UV wavelength of 300 nm. Linearity calculated 0.9829, primary and intermediate precision both were more than 95%. Limit of detection (LOD) and limit of quantification (LOQ) were 3 and 10 µg/l respectively.

Conclusion: The method could simply and with significant reliability be applied to extract and determinate Imipenem in complex hospital wastewater matrixes.

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Background: Vesicoureteral Reflux (VUR) is the most common urologic anomaly in children. In spite of prescribing prophylactic antibiotics in children with VUR, in some cases breakthrough infection (BTI) occurs while receiving prophylactic antibiotics which may cause pyelonephritis that can ultimately lead in renal scarring.

Materials and Methods: In this discreptive-analytic study, 288 children with primary vesicoureteral reflux under Cotrimoxazole(2mg/kg) treatment have been under supervision for duration of at least one year. Based on the collected data, predictive effect of some factors like gender, mean age of VUR diagnosis, VUR grade, unilateral versus bilateral and presence of abnormal renal scar on the breakthrough infection under prophylactic treatment, were examined.

Results: Breakthrough infection while receiving prophylactic antibiotics was observed among 111(38.54%) patients consisting of 88 girls (79.28%) and 23 boys (20.72%). The moderate to high VUR grades (grade III-V), presence of renal scar and female gender were found to be the important risk factors for BTI. However, no statistically significant relationship between mean age of VUR diagnosis and unilateral versus bilateral VUR with BTI was found.

Conclusion: Results of the current study will help improving parents' and physicians' awareness of the risk factors associated with BTI which may potentially lead to renal damage.

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Background: Pseudomonas aeruginosa is one of the major etiologic agents of nosocomial infection among burn patients that has high resistance to antibiotics. Integrons can extend antibiotic resistance genes among bacteria. The aim of this study was to investigate the antibiotic resistance pattern and the prevalence of integron among P. aeruginosa isolates.

Materials and Methods: In this cross-sectional study, a total of 73 P. aeruginosa isolated from burn wound infections among hospitalized patients in Ahvaz Taleghani hospital. Antibiotic resistance pattern of these bacteria was investigated to 9 antibiotics by Disk Agar Diffusion method. Polymerase chain reaction (PCR) method was used to investigate the prevalence of class 1, 2 and 3 integrons. The data were analyzed by Chi-square test. A P-value of <0.05 was considered as a statistical significance level.

Results: The most antibiotic resistance level was seen against ofloxacin (94.5%), aztreonam (94.5%), and ceftazidime (93.6%). Fifteen isolates of P. aeruginosa were resistance to all of the antibiotics. The study of molecular results showed that class 1 integron was detected in 35.6% of isolates, while none of them harbored class 2 and 3 integron.

Conclusion: The rates of antibiotic resistance in pseudomonas aeruginosa to antibiotics such as ceftazidime, oflaxacin, aztreonam, cefepime, and ceftriaxone is very high. Although, class 1 integron were detected in 35.6% of isolates, there was no statistically significant differences between the presence of integron and resistance to a specific antibiotic, that it shows the role of the other antibiotic resistance mechanisms among pseudomonas aeruginosa.

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Background: Agr systems, is responsible for control and coordination in production of virulence factors, exotoxins secretory and hemolysins in Staphylococcus aureus. The aim of this study was to determine and identify the frequency of agr genes in susceptible and methicillin-resistant Staphylococcus aureus strains in clinical samples and carriers employed in remedial centers.

Materials and Methods: This descriptive study was done among a total of 200 strains of Staphylococcus aureus isolated from clinical samples and healthy carriers in Hamadan. Antibiotic susceptibility pattern of all isolates was determined by disk diffusion methods. After DNA extraction, the presence of mecA and agr genes was investigated using PCR. SPSS software package version 20 was used to perform statistical tests.

Results: All 200 Staphylococcus aureus strains were susceprible to vancomycin. The prevalence of mecA was 50%. The PCR results showed that agrA was the most perevalent gene followed by the agrC in all isotated Staphylococcus aureus strains. None of the isolates harbored the agrB and agrD gene.

Conclusion: Pathogenesis of Staphylococcus is dependent on some proteins other superficial or excreted which under controlling of agr system. In the present study, the feequency of agrA gene in the methicillin-resistant strains, methicillin-sensitive strains isolated from clinical samples and carriers employed in remedial centers was higher than the other agr types. Therefore, presumably, agrA gene plays an important role Staphylococcal infections.

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Background: Brucellosis is one of the most important diseases among humans and animals. Clinical management of brucellosis due to an increased rate of treatment failure and recurrence is extremely worrying. The aim of this study was to determine the antimicrobial susceptibility pattern of the brucella isolates.

Materials and Methods: From April to September 2014 a total of 30 brucella isolates that were cultured on brucella agar has been studied. The species identification was carried out and to determine the effect of antibiotics on bacteria antibiogram testing was performed by disk diffusion.

Results: In this study, 30 brucella strains were isolated from cultured specimens and antibiogram testing was performed. All microbial positive specimens were sequenced by PCR. All isolates were Brucella melitensis. According to the tests, suceptibility to tetracycline, minocycline, gentamicin, tigecyclin was 100%, to doxycycline 93.3%, co-amoxiclave 66.7%, rifampin 44.7%, streptomycin 86.7%, ciprofloxacin 80%, cotrimoxazole 76.7% and ceftriaxone 73.3%.

Conclusion: This study shows that the predominant strain in our patients was Brucella melitensis. Also, due to high levels of resistance to rifampin to use the other effective drugs like gentamicin, streptomycin, ciprofloxacin or cotrimoxazole in combination with doxycycline or tetracycline.

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Background: The efflux pumps are one of the main mechanisms of resistance to antibiotics in E. coli and K. pneumoniae strains. The aim of this study is to study the association between genes coding efflux pumps AcrAB and Qep A and ciprofloxacin resistance among E. coli and K. pneumoniae clinical strains

Materials and Methods: This study was done on 100 strains of E. coli isolated from Taleghani and Labbafinejad Hospitals and 100 strains of K. pneumoniae isolated from Taleghani and Mofid Children Hospitals. Antimicrobial susceptibility tests were performed by disk diffusion method based on CLSI guidelines. Identification of genes encoding efflux pumps Acr AB and Qep A was done by PCR technique.

Results: In this study, fosfomycin and imipenem had the best effect against E. coli clinical isolates and fosfomycin and tigecycline had the best effect against K. pneumoniae clinical isolates. PCR assay demonstrated that the prevalence of AcrA, AcrB and QepA genes among E. coli isolates were 92%, 84% and 0%, respectively and among K. pneumoniae isolates were 94%, 87% and 4%, respectively.

Conclusion: The prevalence of genes encoding efflux pumps in E. coli and K. pneumoniae clinical strains, which causes resistance to fluoroquinolones, is cause for concern. Therefore, controlling infection and preventing the spread of drug-resistant bacteria needs to manage medication carefully and identify resistant isolates.

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Background and Aim: The widespread use of antibiotics has been led to increased emergence of antibiotic resistant bacteria and high mortality and morbidity rates due to infectious diseases. Pseudomonas aeruginosa is one of the most important causes of nosocomial infections, which shows high resistance to a wide range of antibiotics. So, finding new and effective antimicrobial compounds in order to overcome antibiotic resistant infectious diseases is so critical. Screening of native actinobacteria can be an effective strategy to find novel antimicrobial compounds. The aim of current study was isolation, screening and identification of rare actinobacteria to find the strains which produce antimicrobial compounds against P. aeruginosa. Material and Methods: Thirty samples of water and sediments were collected from Persian Gulf and Oman Sea and used for isolation of actinobacterial strains. After isolation of actinobacteria, their metabolites were extracted and their anti-P. aeruginosa activities were investigated. Minimum inhibitory concentration (MIC) of the most efficient extract was determined using broth microdilution method. Finally, the most efficient strain was identified. Ethical Considerations: In this study, all principles of biosafety and bioethics have been considered. Findngs: Fifty actinobacteria were isolated from water and sediments. Five isolates had considerable antimicrobial activity. MIC value of the most efficient extract against P. aeruginosa was 100 µg/ml. Molecular analysis of 16SrRNA showed that the most effective fermentation broth extract belongs to Micromonospora and has 99.8% similarity to M. chalcea. Conclusion: The current study revealed that the water of southern Iran and their sediments are promising sources of potent rare Actinobacteria in the production of antimicrobial compounds against P. aeruginosa.

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