فاطمه نوربخش

The indiscriminate use of antibiotics has led to the emergence of antibiotic-resistant bacterial strains, highlighting the need for alternative therapeutic strategies such as probiotics. This study aimed to investigate the inhibitory effects of bacteriocin derived from Lactobacillus plantarum and the antibiotic polymyxin B on biofilm formation and certain virulence factors of Pseudomonas aeruginosa.

In this experimental study, 30 clinical isolates of P. aeruginosa were obtained from various clinical samples. The isolates were identified using standard biochemical and microbiological assays. Bacteriocin was extracted from the L. plantarum strain MT.ZH293. The effects of bacteriocin and polymyxin B on biofilm formation, surface hydrophobicity, alginate production, and bacterial motility were assessed. The minimum inhibitory concentration (MIC) was determined using the microdilution method.

For polymyxin B, the MIC was 4 µg/mL in 13.33% of isolates and 8 µg/mL in 86.6% of isolates. Regarding bacteriocin, 20% of isolates showed an MIC of 125 µg/mL, while 80% exhibited an MIC of 250 µg/mL. Following treatment with polymyxin B, 46.6% of isolates formed strong biofilms, 46.6% moderate, and 6.6% weak biofilms. In contrast, treatment with bacteriocin resulted in 13.3% of isolates forming moderate biofilms and 86.6% forming weak biofilms. Bacteriocin was more effective than polymyxin B in inhibiting biofilm formation, reducing surface hydrophobicity, and suppressing alginate production. Additionally, bacteriocin exhibited greater inhibition of twitching motility (within the range of 40 to 60 mm), while both treatments enhanced swarming motility.

The bacteriocin derived from L. plantarum demonstrated greater efficacy than polymyxin B in inhibiting biofilm formation and associated virulence factors, such as surface hydrophobicity and alginate production in P. aeruginosa. Thus, this bacteriocin may serve as a promising alternative strategy for managing antibiotic-resistant bacterial infections.

The purpose of this study was to investigate the antimicrobial activity of bacteriocins produced by lactic acid bacteria against beta-lactamase producing bacteria and to evaluate its synergism effect with some antibiotics.

In this study, bacteriocin was isolated from Lactobacillus acidophilus strains, and then the effect of produced bacteriocin against 3 pathogenic bacterial strains, Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa was investigated by serial dilution method. The effectiveness of bacteriocin extract alone and in combination with commercial antibiotics against clinical pathogens was determined using the disk diffusion method in three replicates.

The results showed that all Pseudomonas aeruginosa and Acinetobacter baumannii strains were beta-lactamase positive. This study showed a statistically significant difference in bacteriocin-antibiotic synergism activity for ceftazidime, levofloxacin, and piperacillin in Pseudomonas aeruginosa strains and in Acinetobacter baumannii strains for tetracycline, gentamicin, and ceftazidime.

Lactobacillus acidophilus bacteriocin along with some antibiotics showed synergism effect in beta-lactamase producing strains of Pseudomonas aeruginosa, Acinetobacter baumannii and Escherichia coli.

Pseudomonas aeruginosa is one of the most common opportunistic microorganisms causing infections in a wide variety of patients. Increasing intrinsic and acquired resistance to antibiotics is a global challenge for the treatment of infections. The aim of this study is to evaluate the extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase activity of Pseudomonas anrogenase isolated from clinical specimens. In this research 55 strains of Pseudomonas aeruginosa isolated from clinical patients were identified by biochemical methods and then their antibiotic resistance pattern was determined by diffusion method. The strains producing ESBLs were evaluated by combined test and AmpC by the double synergism phenotypic method. Molecular methods were also used to detect strains carrying ACC, FOX, MOX, DHA, MIR, CMY, TEM, SHV and CTX genes. In this study, the highest resistance was to the antibiotic meropenem (52.7%) and the lowest resistance was to the antibiotic colistin (1.8%). When the synergism of the double discs was examined, 61.8% of the strains were found to produce AmpC. None of the strains in this study were ESBLs. The frequencies of DHA, MOX, FOX, ACC, SHV and CTX genes were 30.9%, 12.7%, 81.8%, 27.3%, 5.5% and 5.5%, respectively. MIR, CMY and TEM genes were not observed in any of the strains in this study. The results showed the frequency of the FOX gene among the strains and the greater resistance of these strains to the antibiotic meropenem, and AmpC β-lactamase activity was evaluated as an important factor in the occurrence of antibiotic resistance.

One of the characteristics of lactobacilli is their ability to produce biosurfactant compounds. In this research, the biosurfactant of Lactobacillus acidophilus and Lactobacillus casei was used to evaluate the antimicrobial and anti-biofilm potential against four pathogenic bacteria including Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii.

Biosurfactant extraction was done from Lactobacillus acidophilus and Lactobacillus casei, using the method of determining the minimum growth inhibitory concentration (MIC) was used to determine the antimicrobial potential. Also, the micro titer plate method was used to measure the anti-biofilm potential and the type of biofilm of each strain was determined in the presence of Lactobacillus acidophilus and Lactobacillus casei biosurfactant in different concentrations.

Determination of the minimum inhibitory concentration (MIC) for pathogen strains, the highest percentage was observed at the concentration of 125 and 250 mg/ml. The anti-biofilm effect of biosurfactant has been used in the approximate concentrations of 62.5 mg/ml, 125 mg/ml and 250 mg/ml. Determination of antibiotic sensitivity showed the results of sensitive, semi-sensitive and resistant states, but the results obtained for Acinetobacter baumannii shows resistance to all antibiotic discs.

The biosurfactant isolated from Lactobacillus acidophilus and Lactobacillus casei had antibacterial properties against pathogenic bacteria, also the biosurfactant of Lactobacilli showed that it has anti-biofilm capability.

Pseudomonas aeruginosa is an opportunistic pathogen and a major cause of nosocomial infections. Metallobetalactamases and carbapenemases are the most important factors in resistance to carbapenem drugs in Pseudomonas aeruginosa strains. The aim of this study was to evaluate the activity of metallobetalactamase and carbapenemase in Pseudomonas aeruginosa isolated from clinical specimens. 49 strains of Pseudomonas aeruginosa isolated from patients admitted to the intensive care unit were identified by biochemical methods, then their antibiotic susceptibility was determined by Kirby- Bauer method. MBL producing strains were identified by phenotypic method combined disk test and KPC- producing strains were evaluated by MHT method. PCR method was also used to identify strains carrying VIM, SIM, GIM, SPM and IMP genes. Antibiotic resistance to ticarcillin, meropenem, gentamicin, ciprofloxacin, cefpime and ceftazidime were 89.8%, 51%, 44.9%, 67.4%, 93.9%, 95.9%, respectively. By phenotypic analysis combined disk test, 55.1% of the strains were identified as metallo-betalactamase producing strains. Also, 38.8% of carbapenemase producing strains were observed by MHT method. The frequencies of each of these gene’s VIM, SIM and GIM were 63.3%, 38.8%, 34.7%, respectively, and SPM and IMP genes were not observed in any of the strains in this study.

B- lactam antibiotics is one of the most important antibiotic used worldwide for bacterial infectiouse diseases. By producing beta-lactamase enzymes in bacteria the central ring in beta-lactam antibiotics is hydrolyzed, and antibiotic inactivate and develop resistance.

In this article, it is discussed.a brief review of various methods of inactivation of beta-lactam antibiotics by bacteria.

This review article has been written by studying the articles that have been published in scientific journals regarding the inactivation mechanisms of various beta-lactam antibiotics. 

Beta-lactam antibiotics, by binding to the penicillin-binding protein present in the bacterial cell membrane, inhibit transpeptidases and break down the peptidoglycan, resulting in the destruction of the cell wall and the death of the bacteria. Beta-lactamase enzymes hydrolyze and inactivate beta-lactam antibiotics before they reach the penicillin-binding protein in the cytoplasmic membrane. So far, more than 140 different types of beta-lactamase have been identified, which are classified based on different criteria and effective on different classes of beta-lactam antibiotics.

The use of broad-spectrum cephalosporins in the treatment of infections has led to the emergence of a new class of beta-lactamases called metallobetalactamase, these enzymes belong to Ambler's class B beta-lactamases. Group A and B metallobetalactamases in Enterobacteriaceae cause problems in treatment. The present study was conducted with the aim of phenotypic investigation of Escherichia coli and Klebsiella pneumoniae metallobetalactamase producing strains, as well as molecular investigation of SPM, VIM, SIM, IMP and GIM genes.

The present descriptive-quantitative study was conducted on 185 patients hospitalized in the special care units of Milad Hospital in Tehran from March to May 2018-2019, and 45 strains of Escherichia coli and 62 strains of Klebsiella pneumoniae were selected. In order to check the antibiotic resistance of the strains, diffusion test in agar was used and also to check the phenotypic of the metallobetalactamase producing strains, the combined disc method was used. Molecular investigation of metallobetalactamase producing genes was done by PCR method. The collected data were analyzed using Fisher's test.

In the present study, the highest antibiotic resistance of Escherichia coli and Klebsiella pneumoniae strains was observed to cotrimoxazole and cefepime antibiotics, respectively. 14.5% of Klebsiella pneumoniae strains and 15.5% of Escherichia coli strains produced metallobetalactamase enzyme in the phenotypic method. Also, 88.9% of the studied Escherichia coli strains carried the SPM gene, 40% carried the VIM gene, 66.7% carried the SIM gene, and 15.6% carried the IMP gene. SPM, VIM, SIM, IMP and GIM genes were found to be 54.8, 41.9, 58.1, 3.2 and 8.1% in Klebsiella pneumoniae strains, respectively.

In the present study, there was a high percentage of genes producing metallobetalactamase enzyme in bacteria, while 14.5% of Klebsiella pneumoniae strains and 15.5% of Escherichia coli strains were producing metallobetalactamase enzyme in the phenotypic method. that genes producing enzymes exist in bacteria and are not expressed in high amounts. There waS also the possibility that these genes were expressed, but could not be checked with the usual phenotypic methods, so efforts should be made to find reliable, cheap and easy phenotypic methods for phenotypic examination.

Here, the aim was to study the Factors affecting the intention of tourists to visit the tourist attractions of Kerman province with emphasis on e-marketing. The present study is a descriptive correlation in terms of method of data collection and analysis, and the data collection tool in this study was a standard questionnaire. The validity of the questionnaire was calculated and confirmed using confirmatory factor analysis and content validity. The reliability of the questionnaire and its variables were calculated and confirmed using Cronbach's alpha coefficient. The statistical sample of the study consisted of 433 Iranian and foreign tourists who visited the tourist attractions of Kerman province in 2020-2021. Due to the prevalence of coronary heart disease, the research questionnaire was distributed and collected in person or after receiving the e-mail address. The results showed that electronic advertising with a coefficient of 0.73 and a value of t, 10.276 has an effect on word of mouth electronic marketing, and with a coefficient of 0.26 and t, 4.626 on the destination image. Also, the image of the destination affects the attitude towards it with 0.93 and t, 13.341. Finally, the results show the effect of word of mouth electronic marketing with 0.16 and t, 3.725 and attitude towards the destination with 0.81 and t, 11.978 with the intention to visit.

Psoriasis is a chronic and inflammatory skin disease, which is has no definitive cure. Several microbial agents have been identified that have a role in the exacerbation of psoriasis, one of which is Staphylococcus aureus. Increased Methicillin-resistance Staphylococcus aureus (MRSA) strains is a major problem worldwide. This study aims to evaluate the antibacterial effect of Cinnamomum zeylanicum essential oil on MRSA strains isolated from skin lesions in patients with psoriasis.

In this study, participants were 140 patients with psoriasis referred to the dermatology and rheumatology clinic of Shariati Hospital in Tehran, Iran. Diagnostic tests including gram staining, catalase test, tube coagulase test, mannitol fermentation test, and deoxyribonuclease test were performed. To identify the phenotype of MRSA strains, methicillin susceptibility testing was performed using cefoxitin by disk diffusion method. The antimicrobial activity of Cinnamomum zeylanicum essential oil was investigated by broth microdilution method and its minimum inhibitory concentration against MRSA strains was calculated.

Of 140 patients, 43.57% had infection with Staphylococcus aureus and 14.28% had MRSA infection. There was no significant relationship between gender, age and sampling area in patients with MRSA infection. The results showed that Cinnamomum zeylanicum essential oil had antimicrobial effects on MRSA strains.

The Cinnamomum zeylanicum essential oil can be a suitable alternative to antibiotics for the control and treatment of skin infections caused by Staphylococcus aureus.

Nowadays Among the mass media, television has shown a considerable interest and power. The objective of this research is identifying and designing the islamic marketing indicators in advertisement circuit and checking adjustment accommodation of television commercial advertisements with islamic marketing indicator. In this research , the islamic marketing indicators were exploited by using islamic resources and accommodate to expert pool in islamic management and commerce curcuit and 23 indicators were confirmed by them.In the research, among the whole commercial broadcast in channels 1,2,3 and 5, 323 of them were selected as samples from 96/1/15 to 96/3/15. Those selected advertisements were conformed with the 23 final indicators and were criticised by content analysis method.The results represent that amongst the whole indicators only 5 cases of them were perfectly observed in advertisements and other 18 indicators were totally disregarded.Hence the nonconformity of islamic marketing indicators was observable in most advertisements broadcast.

Acinetobacter baumannii is an opportunistic pathogen that remains persistent in the environment for a long time. The eradication of this bacteria is difficult, since it has the ability to acquire antibiotic resistance. The aims of this study were to identify the ampC Betalactamas genes and antibiotic sensitivity of Acinetobacter baumannii strains. Sixty three strains of Acinetobacter baumannii isolates from wound, blood, and respiratory secretions were isolated and identified by biochemical tests. Antimicrobial susceptibility testing against five antibiotics was performed by disc diffusion method for all isolates. Phenotypic methods combined disc test (CDT), was performed for idenfication AmpC Betalactamase activity in bacteria. The presence of AmpC Betalactamase and ISAba-1 and ISAba-2 genes were evaluated by PCR. Disk difiusion result showed that all of samples were resistance to 5 antibiotics ceftriaxone, cefoxitin, ceftazidime, cefotaxime and cefepime. Combined Disk test result showed that (63%) of samples were strong (30%) weak and (6%) of negative. AmpC betalactamase gene in 90.5% were positive and in 9.5% were negative. All of sampls had ISAba-1 gene (69.2%) had ISAba-2. Current study showed a high percentage of AmpC Betalactamas genes and also high prevalence of antibiotic resistance in Acinetobacter baumannii

Acinetobacter baumannii is an important bacteria because of high ability to obtain antibiotic resistance genes and creation of multi-drug resistant strains (MDR). Today, the active efflux pumps has been suggested as one of the most important mechanisms of intrinsic and acquired resistance of antibiotics in bacteria. The aim of this study was Evaluation of phenotypic and genotypic expression of efflux pumpin clinical isolates of Acinetobacter baumannii resistant to ciprofloxacin and gentamicin.

Twenty eight strains of Acinetobacter baumannii were isolated from wound of patients were admitted to Tehran heart  hospital and diagnosed by biochemical tests. Antibiotic susceptibility of isolates was determined by disc diffusion method according to CLSI. Cartwheel method was used to determine the activity of the efflux pump after determining the antibiotic resistant profile, the expression of adeA, AdeB and AbeM gene evaluated by RT-PCR

Antibiotic susceptibility test of isolated Acinetobacter baumannii show a high resistance to ciprofloxacin, gentamicin, tetracycline and imipenem antibiotics in all strains. The results of the cartwheel were identical before and after the administration of the ciprofloxacin and gentamicin antibiotics. Also Antibiotic resistance to the gene expression of adeA, adeB and abeM were up to 50%.

Evalution of phenotypic result of efflux and gene expression of the efflux pump indicates that, there is no significant relationship between the efflux pump in phenotypic method and the molecular method of gene experssion of adeA, adeB, abeM in presences of to ciprofloxacin and gentamicin.

Biofilms are microbial aggregates that adhere to a substrate as a surface and are surrounded by an exopolysaccharide matrix. The bacteria that make up biofilms are so resistant to antimicrobials and antibiotics that this has led to concerns in the medical community.The aim of this study was effect of silver nanoparticles on surface hydrophobicity and biofilm formation in Staphylococcus aureus, Acinetobacter baumannii, Pseudomonas aeruginosa and Escherichia coli. This study was performed on 40 bacterial strains including Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli and Acinetobacter baumannii isolated from Milad Hospital in Tehran. The strains were identified by biochemical tests. Also, biofilm formation by microtiter plate method, surface hydrophobicity by MATH method and sensitivity of strains to silver nanoparticles were evaluated. According to the results obtained in this study, all strains were able to form biofilms and no strains with negative biofilms were observed in the study. The highest effect of silver nanoparticles in this study was observed on strains at concentrations of 0.5, 1 and 2 μg / ml. Also, only 20% of Pseudomonas aeruginosa strains in this study were observed with moderate hydrophobicity and the others of the bacteria were weakly hydrophobic. silver nanoparticles in low concentrations with the effect of low toxicity had the ability to inhibit the biofilm formation of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Acinetobacter baumannii. Hydrophobicity in the studied bacteria were weak.

One of the most important problems in treatment centers is the infectious diseases caused by antibiotic resistant Acinetobacter Bumanni. This study aimed to isolate and identify carbapenemase and metallo-beta-lactamase producing strains using phenotypic and molecular methods.

In this study 79 strains of Acinetobacter Bumanni were isolated from patients hospitalized in Tehran Heart Hospital and identified by biochemical tests. Antibiotic susceptibility of isolates was performed by disc diffusion method. Phenotypic methods such as combined disk test (CDT), double disk synergy test (DDST), and Modified Hodge test (MHT) were performed to identify carbapenemase and metallo-beta-lactamase activity. PCR was performed using specific primers for OXA- 48, OXA-23, and NDM genes.

In this study, the highest resistance in A. baumanii was observed to imipenem and ertapenem by disk diffusion method. By CDT, 96.2% of isolates showed carbapenemase activity and 94.93% showed metallo-beta-lactamase activity in presence of imipenem. Also, by DDST, 86.07% and 91.13% of isolates showed Carbapenemase and metallo-beta-lactamase activity, respectively, and 91.14% of isolates were positive by MHT. The molecular method showed that OXA-48 gene was in 100% of isolates and OXA-23 gene was in 98.73% of isolates and NDM gene did not exist in isolates.

Based on the results, CDT has high susceptibility in other phenotypic methods for identifying carbapenemase and metallo-beta-lactamase activity. Frequency of OXA-48 and OXA-23 genes revealed antibiotic resistance in A. baumanii isolates.

Staphylococcus aureus is an important human pathogenic bacterium and one of the pathogens that commonly causes biofilm infections in the clinic. Antibiotic resistance has spread worldwide in Staphylococcus aureus and is a serious problem for the treatment of patients. In this study, the effect of thyme essential oil of Shirazi and cinnamon on the formation of biofilm in Staphylococcus aureus strains has been investigated.

In this study, 20 clinical samples of Staphylococcus aureus were isolated from the urine of patients admitted to the intensive care unit of Taleghani Hospital in Tehran. The microdilution test was performed to determine the minimum inhibitory concentration (MIC) of Zataria multiflora and cinnamon essential oils on strains. The ability of biofilm formation in the collected strains was assessed by microtiterplate and the effects of Zataria multiflora and cinnamon essential oils were evaluated on biofilm formation.

In this study, 75% of Staphylococcus aureus strains formed strong biofilm and 25% moderate biofilm. Treatment of Staphylococcus aureus strains with Zataria multiflora essential oils in MIC concentration revealed that biofilm formation were 40% weak and 60% strains did not form biofilm. Treatment of strains with cinnamon essential oil at MIC concentration was observed to be 25% strong biofilm and 75% moderate biofilm. The present study shows the effect of essential oils of Zataria multiflora and cinnamon in reducing the biofilm formation of Staphylococcus aureus strains.

In the wake of recent financial crisis, large banks have been considered as important factors in financial markets in the world, since these bankschr(chr('39')39chr('39')) failure could affect the whole economy by extending systemic risk. With regard to this issue, when large banks face insolvency or bankruptcy, larger part of economy would be affected, and with the interconnectedness between banks and financial institutions, the effects of large bankschr(chr('39')39chr('39')) bankruptcy will have greater impact on the real economy. After financial crisis, many studies have concentrated on the failure of TBTF banks, and the role of these banks in the incident of financial crisis. Number of specialists emphasize on bank size and Basel Committee on Banking Supervision regulated by the classification of banks and their systemically important banks. The study of risk among systemically important banks is important to Basel Committee on Banking Supervision. Many studies confirm that larger banks tend to have less capital, less stability and sustainability of resources, and higher risk-taking activities, therefore, larger banks have become fragile in financial markets.

Many valuable drugs have now lost their effect on Acinetobacter baumannii, and the drug resistance of A. baumannii is a major cause of failure in the treatment of hospital infections. The aim of this study was to investigate the effect of Thymus vulgaris essential oil and ZnO nanoparticles on multidrug resistant Acinetobacter baumannii.

This study was performed on 46 strains of A. baumannii isolated from clinical samples of patients at Tehran Heart Hospital. Antibiotic susceptibility of the isolates was determined by disk diffusion method according to CLSI 2018 standard. Micro-dilution broth test was then performed to determine the minimum inhibitory concentration (MIC) for amikacin, ciprofloxacin , imipenem antibiotics, T. vulgaris essential oil and ZnO nanoparticles.

Based on the results of disk diffusion sensitivity tests, it was found that the highest resistance to imipenem and ciprofloxacin antibiotics were 97.82%. In the present study the most susceptible strains to the T. vulgaris essential oil were observed at concentration 0.5 µg/ml and the least sensitivity at concentrations 0.312 and 0.625 µg/ml. also based on the results obtained in this stady the highest susceptible strains to ZnO nanoparticles was at concentrations 4096 µg/ml and the lowest sensitivity at concentrations 256 µg/ml.

the results of this study indicate the potent inhibitory effect of T. vulgaris essential oil and ZnO nanoparticles on Acinetobacter baumannii

Acinetobacter baumannii is the important cause of nosocomial infections worldwide due to its propensity to rapidly acquire resistance determinants to a wide range of antibiotics and is the major of Multidrug resistant bacteria. There are many different mechanisms for occurrence of MDR in A. baumannii isolates that efflux pumps, beta-lactamases, integrons, insertion sequence(IS) and structural proteins. 79 strains of Acinetobacter baumannii wereisolated from clinical specimens of patients were admitted to Hearth Tehran hospital and diagnosed by biochemical tests. Antibiotic susceptibility of isolates was determined by disc diffusion method according to CLSI 2015. Finally, DNA were extracted and presence of adeA, adeB and adeC genes was evaluated by PCR. The resistance to amikacin, ceftazidime, ciprofloxacin, meropenem, imipenem, tetracycline and trimetoprim were 83.75%,86.25%,82.5%,86.25%,91.25%, 58.75%t 93.75%   respectively. The frequency of adeA,adeB was similar 96.2%  and for adeC gene the frequency was 91.1 % .There was a significant relationship between imipenem and meropenem resistance and frequency of efflux pump genes. According to high prevalence of AdeABC efflux system genes may be play an important role in antibiotic resistance of A. baumannii clinicalisolates specially imipenem and meropenem resistace. Althouth it must be mentioned the role of efflux pumps gene expression in antibiotic resistance.

Wastewaters are the main source of many water pollutants in Iran and the world. Widespread environmental pollution is a danger that threatens future generations. Microfiber fuel cell (MFC) as a multi-purpose renewable energy technology can be used in the treatment of various wastewater and generation of electricity or bio-hydrogen, simultaneously. In this review paper, the performance of MFCs with the criteria of power generation, removal of toxic pollutants such as heavy metals and wastewater treatment efficiency with parameters such as chemical oxygen demand (COD) and coulombic efficiency (CE) are presented. According to the high diversity of wastewater that has been investigated over the past few years, the presented subjects in this paper has been divided into several groups of synthetic, food and food-processing, industrial, municipal wastewaters.

  Septicemia or blood infection is one of the most important causes of mortality in patients hospitalized in different parts of hospitals, which is considered as an emergency medical emergency. This study was conducted to investigate the role of Gram-negative bacteria in the development of blood infection in Rokhayee hospital in Karaj. This study was performed on 3500 patients with septicemia suspicious symptoms admitted to Shahid Rajaee Hospital. Samples were taken from patients for blood culture. The bacteria developed in blood cultures were isolated and identified using conventional bacteriological methods. Out of 3500 patients under study during one year, 70 cases of Gram-negative bacteria were isolated in blood cultures, 13 of which were in the first six months of the year and 57 of them were in the second six months. In total, six types of Gram-negative bacteria were isolated from patients (Escherichia coli, Enterobacter, Pseudomonas, Acinetobacter, Yersinia, and Klebsiella). Escherichia coli was the most common bacteria responsible for the infection of the blood. The results of this study showed that Gram-negative bacteria were the main causes of blood infection and mortality and the prevalence of blood infections in the second month was higher

Staphylococcus aureus is one of the most important pathogens acquired of hospital and community. The aim of this study is molecular typing SCCmec cassette chromosome genes in S. aureus strains resistant to methicillin. In this study 106 clinical isolates of Staphylococcus aureus were collected of hospitalized patients in the milad hospital. Antibiotic susceptility test was performed in 106 isolates of Staphylococcus aureus by oxacillin and cefoxitin by disk diffusion method according to CLSI protocol. Fifthy resistant strains were isolated. DNA Extenation of resistant strains were performed by boiling method, SCCmec genotype was determined by PCR and multiplex PCR.A total of 50(47.15%) isolates of S.aureus were MRSA. PCR and typing showed that type I 11 (22%), type II 20 cases (40%), type III (28%), type IVa 7 (14%), type IVb 5 (10%), type IVc 12 ( 24%), type V 9 (18%) were observed and SCCmec type IVd was not observed in isolates. Different Sccmec type is related to the origine of strains isolation and differ in susceptibility to Antibiotics. In this study, type IVa was least Sccmectype and type III and type II were most common genotype in strains, which induce multi drug resistance in strains.

Clindamycin is prescribed to treat the different infections but in some cases, it does not have any medical effect because of different resistance mechanisms in bacteria. A method to counter the resistant bacteria is to use liposomal formulation. Making liposomal formulation needs to measure the content of injected drug into liposome. In this study, a method was proposed to measure the content of clindamycin in liposomal formulation. Criteria of verification based on ICH Q2B protocol included linearity, accuracy, precision, selectivity, sensitivity of diagnosis and determination limits. Initially, each sample was solved in methanol and 0.1M soda with 8:1 and then intensity of attraction for each sample was measured with 201 nm wavelength by UV spectrophotometer. It was possible to draw the calibration curve for clindamycin in range of 0.2 to 8.1 mg/ml with correlation coefficient of 0.999 by this mechanism. This study showed that liposomal formulation obtained by phospholipid (% 2.6), cholesterol (%0.8) and clindamycin (%0.1) and diluted with methanol for 50 times does not have any attraction in 201 nm. Therefore, it is possible to measure the concentration of clindamycin without molecules forming liposome. The capacity of reproducing clindamycin in range of 0.80 and 0.120 is 80% and 83% respectively. The standard deviation for intra- and inter-day precision is lower than 4% and diagnosis and determination limits are 0.43 and 0.131 mg/ml respectively. The result showed that this method can be suitable to measure the content of clindamycin in liposomal formulation.

Salmonella is one of the most important zoonotic pathogens responsible for food-borne infections all over the world. Poultry products are widely acknowledged to be a significant reservoir for Salmonella. This study was done to evaluate the antibiotic resistant of Salmonella enterica producer of beta lactamase spectrum in poultry.
In this descriptive – laboratort study 70 Salmonella enterica serotypes were collected from poultry. All Salmonella isolates were tested to antimicrobial susceptibility testing by the Kirby-Bauer disk diffusion according to Clinical Laboratory Standards Institute (CLSI). Twenty-nine antibiotics were used in this study. Klebsiella pneumoniae; ATCC 700603 was used as quality control strains. The isolates were determined to be ESBL-producing Salmonella by the conventional double-disk synergy and genotypic method.
Among 70 salmonella isolates, the most prevalent serotypes were S.typhimurium and S.enteritidis. All serotypes were susceptible to gentamicin, ciprofloxacin, oflaxacin, imipenem, enrofloxacin. The common resistance was observed to cephalexin (96%), cefazolin (96%) and cephalotin (65%). Among the 70 Salmonella isolates studied, multi-drug resistance was observed in 59 (84%) isolates. Forty-seven (67%) isolates were found to be ESBL-producing isolates. PCR assay of all isolates showed that 17 isolates (33.3%) carried bala CMY2 gene.
This study showed that antibiotic resistance to Salmonella enterica serotypes is due to beta lactamase enzyme in this strain is considerably increased in poultry.