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Showing 11 results for Pseudomonas
Blood Culture Contamination In Children’s Medical Center Of Tehran From April To July 2004
Chitsaz M, Khotaee G, Shhcheraghi F, Poorheydaree N,
Volume 63, Issue 2 (5-2005)
Abstract

Background: Blood culture is the criterion standard for identifying children with bacteremia. However, elevated false-positive rates are common and are associated with substantial health care costs. The aims of this prospective study were to: 1) determine the rate of blood culture contamination 2) determine variety and frequency of contaminant bacteria 3) compare the duration of hospital stay and antibiotic administration in patients with true bacteremia vs those have false positive blood culture.

Materials and Methods: Cross-sectional study conducted April through July 2004 among patients aged 14 years or younger who were admitted at Doctor Garib Children Medical Center of Tehran and had a blood culture obtained as part of their care. Bacterial isolates were identified to species level and medical records were reviewed in all cases with a positive blood culture. A number of clinical and laboratory criteria were used to deciding whether a blood isolate is a pathogen or a contaminant. These include the identify of the micro-organism itself, clinical features such as fever and leukocytosis the proportion of blood culture sets positive as a function of the number of sets obtained and to have an indwelling vascular catheter or prosthetic device.

Results: During the study period, 2877 sets of blood culture were evaluated and the rates of positive blood cultures associated with significant bacteremia and contamination were 1.04% and 5.4% respectively. Among the positive blood cultures, over the 84% of isolates were due to contamination and only 15.95% of isolated strains associated with true infection. The frequency of isolated bacteria with respect to true infection and contamination are as following: S. Aureus (infect: 9.0%, contam: 0.0%), S. Epidemidis (infec: 0.0%, contam: 13.3%), Micrococcus sp. (infec: 0.0%, contam: 4.3%), pseudomonas and related species other than P. aeruginosa (infec: 2.1%, contam: 60.6%), viridans group of streptococci (infec: 1.1%, contam: 2.1%), E.coli (infec: 1.06%, contam: 0.0%), Klebsiella pneumoniae (infec: 0.53%, contam: 0.0%), Enterobacter cloacae (infec: 0.53%, contam: 0.0%), and Acinetobacter baumannii (infec: 0.25%, contam: 0.53%). The mean of hospital stay for patients with true bacteremia, 14.83 days, was not significantly higher than that for patients with false-positive blood cultures (10.08 days). 43 patients had administrated one to three antibiotics after false-positive blood cultures.

Conclusion: The findings indicate that blood culture contamination rate in studied hospital is higher than standard levels, and very high rate of contamination with environmental pseudomonas species shows an unusuall epidemic condition. The findings also suggests high resource utilization and prolong patients stay due to pseudobacteremia.


Prevalence of extended spectrum beta lactamases among strains of Pseudomonas aeruginosa isolated from burn patients
Mirsalehian, Feizabadi, Akbari Nakhjavani, Jabal Ameli, ,
Volume 66, Issue 5 (8-2008)
Abstract

Background: The resistance of Pseudomonas aeruginosa strains to broad spectrum cephalosporins may be mediated by extended spectrum b-lactamases (ESBLs). These enzymes are encoded by different genes located either on chromosome or plasmids. In this study, we determined the antimicrobial resistance patterns of P. aeruginosa isolates and screened for ESBL production.

Methods: After isolation from burn patients in Tehran Hospital, identification of P. aeruginosa isolates were assessed using biochemical tests. We then performed disk agar diffusion (DAD) according to CLSI guidelines to determine the pattern of antimicrobial resistance. The frequency of ESBLs and prevalence of the OXA-10 and PER-1 genes were determined with combined disk and polymerase chain reaction (PCR) methods, respectively.

Results: One hundred strains of P. aeruginosa were isolated. The resistance of these strains to cephpodoxime, aztreonam, ciprofloxacin, ofloxacin, ceftazidime, cefepime, imipenem, meropenem, cefotaxime, levofloxacin, piperacilin- tazobactam and ceftriaxon was 100%, 90%, 83%, 92%, 85%, 88%, 63%, 66%, 98%, 89%, 70% and 91%, respectively. Of these, 40 strains (40%) were ESBL positive, 29 strains (29%) were OXA-10 positive and 18 strains (18%) were PER-1 positive.

Conclusion: Our results confirm the need for proper antimicrobial therapy in burn hospitals, considering the resistance pattern and frequency of strains producing ESBLs and the presence of the OXA-10 and PER-1 genes. Since an increase in the prevalence of ESBL in P. aeruginosa strains might lead to the transfer of these ESBL genes to other gram-negative bacteria, we recommend the use of appropriate drugs, especially cephalosporins, in burn hospitals.


Prevalence of MBL-producing Pseudomonas aeruginosa isolated from burn patients
Mirsalehian A, Akbari Nakhjavani F, Bahador A, Jabal Ameli F, Bigverdi R, Goli H,
Volume 68, Issue 10 (1-2011)
Abstract
Background: Pseudomonas aeruginosa is an important opportunistic pathogen causes clinical infections among burn patients. Metallo-β-lactamases (MBLs) are important mechanisms of Carbapenem (drug of choice) resistance among Pseudomonas aeruginosa isolates. The aims of this study were to determine the antibiotic susceptibility pattern and to detect the prevalence of MBLs among Pseudomonas aeruginosa
Methods: Initially, the antibiotic resistance patterns of 170 clinical strains isolated from burn patients in Motahari Hospital in Tehran, Iran were determined by Kirby-Bauer disc diffusion method. All of the clinical isolates using two phenotypic and genotypic methods.  Pseudomonas aeruginosa isolates resistant to Imipenem were screened for production of MBL by E test with Imipenem / Imipenem plus EDTA (E test MBL). PCR assay was performed for detection of blaVIM genes.
Results: Based on the study results, the percentage of resistance was as below: Imipenem (10 μg) 52.9%, Amikacin (30 μg) 81.7%, Carbenicilin (100 μg) 74.7%, Polymixine B (300 unit) 10%, Ticarcilin (75 μg) 84.7%, Tobramycin (10 μg) 88.2%, Colisitin (10 μg) 34.1, Colisitin (25 μg) 28.3%. Of 90 Carbapenem resistant isolates, 10(11/1%) isolates were positive by E test, all were sensitive to Colisitin and Polymixine B. All of the Imipenem resistant Pseudomonas aeruginosa isolates were examined by PCR for the presence of the blaVIM genes. All MBL-producing isolates carried blaVIM-1 genes.
Conclusion: Considering the high prevalence and clinical importance of MBL-producing isolates, rapid identification of them and use of the appropriate infection control measures are necessary to prevent further spread of infections by these organisms.


The effect of amniotic membrane transplantation in healing of primary stages of pseudomonas keratitis
Soltan Dallal Mm, Nikkhahi F, Khirkhah A, Molaei S, Hosseyni Sk, Rastegar Lari A, Rahimi Foroushani A, Khoshzaban A, Kalafi Z,
Volume 69, Issue 10 (1-2012)
Abstract

Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background: Human amniotic membrane (HAM) forms the inner wall of the membranous sac that surrounds and protects the embryo during gestation. The main advantages of amniotic membrane transplantation (AMT) in the treatment of bacterial keratitis are its epithelial bandage properties. Previous studies have documented the presence of some antimicrobial proteins and peptides in amniotic fluid such as lactoferrin, lysozyme, bactericidal or permeability increasing protein, calprotectin (MRP8/14 protein complex), LL37, and neutrophil defensins (Human Neutrophil Peptides, HNP 1-3). Furthermore, the amniotic membrane does not express HLA-A, B, C or DR surface antigens, which may help avoid rejection after its transplantation. Thus, it can be used as a biological immune barrier. The purpose of this study was to evaluate the effectiveness of the amniotic membrane's healing properties in rabbits with pseudomonas keratitis.
Methods : By using an animal model, 14 rabbits were divided into two groups of controls and cases. A syringe was used to inoculate the corneal stroma of the animals by Pseudomonas aeruginosa ATCC27853. After 20 hours pseudomonas keratitis was created and amniotic membrane was transplanted to the cornea of the case group. The infiltration size were observed on the first, third and seventh days after the experiment.
Results : Corneal perforation was seen in the controls (P<0.001) but amniotic membrane prevented perforation in the case group (P=0.02).
Conclusion: Transplantation of amniotic membrane in the primary stages of pseudomonas keratitis treatment remarkably prevents corneal perforation and it can be used to control the disease process.


Designing of the specific DNA primers for detection of the exoA, oprL and algD pathogenicity genes for rapid diagnosis of Pseudomonas aeruginosa
Mohammad Najafimosleh , Sedighe Rashnotaie , Ehsanollah Ghaznavi Rad, Hamid Abtahi , Gholamreza Taleie ,
Volume 71, Issue 8 (11-2013)
Abstract
Background: The aim of this study was compared the efficacy of  the designed primers and already published primers for detection of the exoA, oprL and algD genes by PCR assay  for finding a rapid, accurate and highly sensitive and specific procedure to detect the Pseudomonas aeruginosa in the serious and fatal infections such as cystic fibrosis disease, burned individual.
Methods: A total of 150 clinical specimens were inoculated in to routine and selective culture media for Pseudomonas aeruginosa isolation. Specific primers were designed by bioinformatics analysis for detection of the virulence genes exoA, oprL and algD. The available sequences of these three genes were obtained from NCBI and multiple alignments were performed to find the conserved sequences of each gene for primer designing. Both multiple alignment and primer designing steps were carried out by AlleleID software, version 7.0.
Results: Microbiological culture methods were showed that 70 Pseudomonas aeruginosa strains isolated from the 150 clinical specimens. PCR assay performed by using the designed primers shown 68, 70 and 69 positive results from 70 direct specimens for exoA, oprL and algD respectively that shown 97.2%, 100% and 98.6% sensitivity for above genes. PCR assay performed by using the already published primers shown 57, 49 and 28 positive results for above genes respectively that shown 81.5%, 70% and 40% sensitivity.
Conclusion: The present study shows that by using the high specific primers for detection of the mentioned genes of the Pseudomonas aeruginosa. The conventional PCR assay detected the early colonization of the organism in Cystic Fibrosis patients with more sensitivity and specificity before several mounts to obtain positive culture. Indeed PCR assay with high specific primers has more sensitivity and specificity as a rapid and accurate diagnosis of the organism in other deadly infections by using the direct clinical specimens.

Evaluation of exotoxin A gene and frequency of polymerase chain reaction sensitivity in detection of pseudomonas aeruginosa isolated from burn patients
Rasoul Yousefi Mashouf, Rasoul Esmaeili, Mohammad Yousef Alikhani , Mehdi Ghanbari ,
Volume 72, Issue 3 (6-2014)
Abstract
Background: Pseudomonas aeruginosa is a gram-negative pathogens opportunism which causes severe infections in human beings. The most common infection include: endocarditis, meningitis, septicemia and chronic lung infections in cystic fibrosis pa-tients. This bacterium has many pathogenic factors including exotoxin A, lipopoly-sacharide, phospholipase C, pili, elastase and alkaline protease. The purpose of this study was to evaluate the frequency of exotoxin A gene (ETA) as a strong virulence factor and sensitivity determination of polymerase chain reaction (PCR) in pseudomonas aeruginosa isolated from second and third-degree burn patients. Methods: This study has performed in Besat University Hospital in Hamadan from January to December 2012. We used 170 isolated samples. The samples were isolated from blood and skin biopsy in second and third-degree burn patients. We had 79 strains positive culture of pseudomonas aeruginosa. Forward and reverse primers used for PCR were designed by DNASIS and Oligo software. Then genomic of known strains were extracted by DNA purification kit and indentified by PCR. The quality and quantity of the extracted DNA was determined using spectrophotometry. For determination of PCR sensitivity was used culture test as gold standard. DNA of pseudomonas aeruginosa (ATCC 27853) was used as a positive control. Finally data was analyzed using SPSS software. Results: Out of 170 isolated samples, 79 strains of pseudomonas aeruginosa isolated from burn patients had positive culture. PCR of isolated positive culture demonstrated that 5 strains (6.33%) were with out this virulence factor and 74 strains (93.67%) had ETA gene. So the sensitivity of test based on sensitivity formula was 94.04%. Conclusion: Our results showed that sensitivity of PCR mediated ETA gene in detection of pseudomonas aeruginosa strains is considerable and this factor can be used as a good factor identifying of pseudomonas aeruginosa. It seems more studies with larger sample size is necessary in this area.
Epidemiology, etiology and outcomes of burn patients in a Referral Burn Hospital, Tehran
Mohammad Mehdi Soltan Dallal , Mohammad Kazem Sharifi Yazdi, Abbas Rahimiforoushani , Mohammad Reza Akhoondinasab ,
Volume 74, Issue 5 (8-2016)
Abstract

Background: Burns and its complications are regarded as a major problem in the society. Skin injuries resulted from ultraviolet radiation, radioactivity, electricity or chemicals as well as respiratory damage from smoke inhalation are considered burns. This study aimed to determine the epidemiology and outcome of burn patients admitted to Motahari Hospital, Tehran, Iran.

Methods: Two hundred patients with second-degree burns admitted to Motahari Referral Center of Burn in Tehran, Iran. They were studied during a period of 12 months from May 2012 to May 2013. During the first week of treatment swabs were collected from the burn wounds after cleaning the site with sterile normal saline. Samples were inoculated in blood agar and McConkey agar, then incubation at 37 C for 48 hours. Identification was carried out according to standard conventional biochemical tests. Treatment continued up to epithelial formation and wound healing. Results of microbial culture for each patient was recorded. Healing time of the burn wounds in patients was recorded in log books. Chi-square test and SPSS Software v.19 (IBM, NY, USA) were used for data analysis.

Results: Our findings indicate that the most causes of burns are hot liquids in 57% of cases and flammable liquid in 21% of cases. The most cases of burns were found to be in the range of 21 to 30 percent with 17.5% and 7% in male and female respectively. Gram-negative bacteria were dominated in 85.7% and among them pseudomonas spp. with 37.5% were the most common cause of infected burns, followed by Enterobacter, Escherichia coli, Staphylococcus aureus, Acinetobacter and Klebsiella spp.

Conclusion: The results of this study showed that the most cause of burns in both sex is hot liquid. Men were more expose to burn than women and this might be due to the fact that men are involved in more dangerous jobs than female. Pseudomonas aeruginosa was the most common organism encountered in burn infection.


The effect of garlic extract on the expression of genes elastase and exotoxin A in Pseudomonas aeruginosa
Batoul Kavyani , Mohammad Yousef Alikhani , Mohammad Reza Arabestani , Shirin Moradkhani , Mohammad Taheri ,
Volume 74, Issue 8 (11-2016)
Abstract

Background: 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.

Methods: 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.

Results: 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.

Conclusion: 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.


In vitro selective growth inhibition of breast adenocarcinoma cell lines by Pseudomonas sp. UW4 metabolites
Maedeh Pasiar , Leila Rouhi , Zahra Bamzadeh , Seyed Hossein Hejazi ,
Volume 74, Issue 9 (12-2016)
Abstract

Background: Breast cancer is a malignant proliferation of epithelial cells that lining the ducts or lobules of the breast. It is the second common cancer, after lung cancer in women. Since growth inhibition is an important strategy in cancer treatment, many attempts are in program to find new apoptotic inducer agents. Today there is some reports about effect of metabolites of Pseudomonas on cancer cells, hence, metabolites of Pseudomonas sp. UW4, were isolated and anti-cancer and anti-microbial activity of these metabolites was studied.

Methods: This experimental study was performed in cellular and developmental biology of Shahrekord Islamic Azad University from April 2015 to August 2015. Anti-microbial activity of metabolites of Pseudomonas sp. UW4 was tested against a pathogenic bacteria, including Escherichia coli, Bacillus cereus and Staphylococcus aureus. For anti-cancer activity, in this study SKBR3 cells and normal fibroblast cells (HU-02) were cultured in DMEM medium with 10% fetal bovine serum (FBS). The cells were treated by various concentrations of these metabolites 5, 10, 15 and 20 mg/ml for 24, 48 and 72 h. Cell viability was assessed by MTS assay. Cells were seeded at 5×103 cells/ml in 96 well plates and incubated for 24 hr. Then metabolites of bacteria were added, after indicated times MTS (20 µl) was added and the absorbance was measured at 492 nm using ELISA plate reader.

Results: Pseudomonas sp. UW4 was able to produce antimicrobial metabolites against Staphylococcus aureus. Metabolites decreases the viability of SKBR3 cell line in a time and dose dependent manner, so that the most effective concentration of this substance was 20 mg/ml and 72 h after treatment (P< 0.01). While Pseudomonas sp. UW4 in various concentrations had no significant effect on normal fibroblast cells (P= 0.24).

Conclusion: Bioactive compounds produced by of Pseudomonas sp. UW4 could be used for elimination of infections and treatment of breast cancer SK-BR3.

A review on the types of immunotoxins and their use in cancer treatment: review article
Saber Soltani , Abolfazl Davoodabadi, Abbas Farahani, Mahsa Dastranj , Masomeh Amini , Navid Momenifar , Shirin Poorabdi , Hojat Veisi ,
Volume 76, Issue 1 (4-2018)
Abstract
Immunotoxins such as pseudomonas exotoxin are Molecules with a unique structure like toxin-antibody part. These immunotoxins are two functional which crossing the cell membrane and enters the target cell and destroy the cell. Toxin-based treatments are a widespread research field and can have broad applications in the biology and public health. Immunotoxins act selectively against cancer cells and have a good potential for detecting and targeting cancer cells. Specific immunotoxins to target immune cells due to the selection type antibody and antibodies are responsible for the identification of the target cells. Cancer is becoming a major cause of death in most developed countries. In order to have a strong factor in cancer repression, that agent must target the cancer cells directly and specifically. Often, but not always, immunotoxins are produced for disabling and killing cancer cells, that this issue is one of new therapeutic approaches in recently. Clinical aims to designing and create new cancer therapies focused with this approach, a lot of information about the toxin and intracellular pathways have been obtained. So, toxins in medicine are useful for the treatment of human disease and study of professional cellular functions. So, immunotoxins have a high potential for cancer treatment. Other applications of immunotoxins, including immune system regulation and treatment of viral diseases and parasites diseases. More research is needed to improve the immunotoxin effects and to reduce their side effects. On the whole, with design creative, clever and experienced programs, many human diseases, particularly cancers can be in a short period of time and faster than other methods of treatment that the treatment of long, to be treated. Following the design and implementation of clinical trials, the effects of immunotoxins on animal tumorigenic models were performed. In fact, in this study, we focus on the use of protein-bound toxins with bacterial and herbal sources and more specifically Pseudomonas immunotoxins which attached to antibodies to target cancer cells.

Determining a pattern for antibiotic resistance in clinical isolations of pseudomonas aeruginosa
Shahram Shahraki Zahedani , Mojdeh Jahantigh , Yousef Amini ,
Volume 76, Issue 8 (11-2018)
Abstract
Background: Pseudomonas aeruginosa is an opportunistic pathogen and one of the important factors of hospital infection. It causes many issues such as urinary tract infections, respiratory infection in cystic fibrosis patients, and wound infection in burn patients, septicemia and meningitis. Antibiotic resistance through various mechanisms is one of the challenges for the treatment of pseudomonad-caused infections. According to the inherent and acquired capacity of this bacterium in creating resistance against the antimicrobial factors, it is very important to identify a pattern for its antibiotic resistance. The aim of this study was to deliberate the frequency of pattern antibiotic resistance of pseudomonas aeruginosa strains.
Methods: In this cross-sectional study, 200 pseudomonas aeruginosa isolations (from 86 males and 114 females) were collected from different samples such as urine, blood, wound, catheter and other samples from teaching hospitals in Zahedan City during nine-month period in 2017. After conducting biochemical tests and confirming bacterium type, based on Clinical Laboratory Standards Institute (CLSI), the antibiotic resistance of strains for 10 antibiotics was determined using disk diffusion method. In addition, the minimum inhibitory concentration of three antibiotics such as imipenem, piperacillin/tazobactam and ceftazidime were determined through E-test. The Chi-square test was used for statistical analysis through the SPSS software, version 16 (IBM SPSS, Armonk, NY, USA).
Results: Out of 200 pseudomonas aeruginosa isolations (from 86 males and 114 females), the maximum resistance was related to ciprofloxacin (37%) and gentamicin (28.5%). The minimum resistance was related to piperacillin/tazobactam (6.5%) and ceftazidime (6%). The highest separated strain was from urine sample (54%), blood sample (23.5%) and wound sample (10.5%). Additionally all strains were sensitive to colistin. In this study, the percentage of multidrug-resistance (MDR) and extensively drug-resistant (XDR) strains were investigated, which were 13% and 5.5%, respectively.
Conclusion: In this study, pseudomonas aeruginosa isolates had the lowest resistance to ceftazidime which this antibiotic could be the main treatment option. The high prevalence of MDR strains is a serious warning.

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