Molecular investigation of exoU and exoY virulence genes in Pseudomonas aeruginosa collected from hospitalized patients in North of Iran:A descriptive-analytical study

Objective:To investigate the frequency of exoU and exoY genes in patients with Pseudomonas aeruginosa infection.Methods:In this study,100 clinical isolates of Pseudomonas aeruginosa were collected from patients hospitalized in educational-therapeutic hospitals and were identified using standard microbiological tests.Then,the antibiotic resistance pattern of the isolates was determined by the disk agar diffusion method.The bacterial DNAs were extracted by the alkaline lysis method.Finally,the presence of exoU and exoY genes was evaluated by the PCR test.Results:In this study,47%,72%,29%,39%,40%,and 44%of the isolates were non-susceptible to piperacillin,aztreonam,ceftazidime,imipenem,tobramycin,and ciprofloxacin,respectively.In addition,95%and 93%of the clinical isolates carried the exoU and exoY genes.Blood and fecal isolates had both virulence genes,while only one wound isolate had neither genes.Meanwhile,all urinary isolates contained the exoY gene and only one isolate lacked the exoU gene.Also,88 isolates simultaneously had both exoU and exoY genes.Conclusions:High prevalence of exoU and exoY genes in this region indicates a significant role of typeⅢsecretion system in pathogenesis of Pseudomonas aeruginosa.The typeⅢsecretion system may be a suitable target to reduce the pathogenicity of this bacterium.

Prokaryotic Expression of Pseudomonas Aeruginosa Lipase Gene

[Objective] The aim of this study was to investigate the prokaryotic expression of pseudomonas aeruginosa Lipase gene.[Method]Lipase gene was amplified by PCR from the genome DNA of pseudomonas aeruginosa,and its nucleotide sequence was determined.The prokaryotic expression vector of Lipase gene was constructed by the gene recombination technique.The protein expression was induced for 4 hours by IPTG with the final concentration of 1.0 mmol/L,and then SDS-PAGE electrophoresis was analyzed.[Result]The sequence of mature peptides in Lipase gene cloned from pseudomonas aeruginosa had a 99.36% homology with that of pseudomonas aeruginosa lipase submitted in NCBI,so the prokaryotic expression vector of Lipase gene pET32a-Lip was successfully constructed.Furthermore,the results of SDS-PAGE electrophoresis showed that the target gene was expressed highly and effectively.[Conclusion]The cloned pseudomonas aeruginosa lipase with its signal peptide could be normally expressed in E.coli and also used for further study.

不同酚类成分及其组合对P.aeruginosa PAO1的抑制效果研究

为研究茶叶酚类成分及其复方对P.aeruginosa PAO1的体外抑制作用,筛选出用药量最低的最佳抑菌组方,采用倍比稀释法结合刃天青显色测定5种酚类成分对P.aeruginosa PAO1的最小抑菌浓度(MIC),并采用响应面法研究对P.aeruginosa PAO1具有较强抑制作用的最佳配伍。结果表明5种酚类成分对P.aeruginosa PAO1均有不同程度的抑制作用,5种茶叶活性成分对P.aeruginosa PAO1的抑菌性大小为:EGCG>TF60=ECG>EGC>EC。响应面分析结果表明,EGCG、EGC、ECG、TF60这4种酚类成分以1.0∶4.0∶4.81∶4.0的比例配伍时对P.aeruginosa PAO1具有最佳抑菌效果。

Microbiologically influenced corrosion resistance enhancement of coppercontaining high entropy alloy Fe_(x)Cu_(1−x)CoNiCrMn against Pseudomonas aeruginosa

To enhance the microbiologically influenced corrosion(MIC)resistance of FeCoNiCrMn high entropy alloy(HEAs),a series of Fe_(x)Cu_((1−x))CoNiCrMn(x=1,0.75,0.5,and 0.25)HEAs were prepared.Microstructural characteristics,corrosion behavior(morphology observation and electrochemical properties),and antimicrobial performance of Fe_(x)Cu_((1−x))CoNiCrMn HEAs were evaluated in a medium inoculated with typical corrosive microorganism Pseudomonas aeruginosa.The aim was to identify copper-containing FeCoNiCrMn HEAs that balance corrosion resistance and antimicrobial properties.Results revealed that all Fe_(x)Cu_((1−x))CoNiCrMn(x=1,0.75,0.5,and 0.25)HEAs exhibited an FCC(face centered cubic)phase,with significant grain refinement observed in Fe_(0.75)Cu_(0.25)CoNiCrMn HEA.Electrochemical tests indicated that Fe_(0.75)Cu_(0.25)CoNiCrMn HEA demonstrated lower corrosion current density(i_(corr))and pitting potential(E_(pit))compared to other Fe_(x)Cu_((1−x))CoNiCrMn HEAs in P.aeruginosa-inoculated medium,exhibiting superior resistance to MIC.Anti-microbial tests showed that after 14 d of immersion,Fe_(0.75)Cu_(0.25)CoNiCrMn achieved an antibacterial rate of 89.5%,effectively inhibiting the adhesion and biofilm formation of P.aeruginosa,thereby achieving resistance to MIC.

Phospholipase C from Pseudomonas aeruginosa and Bacillus cereus:characterization of catalytic activity

Objective:To study characteristics of phospholipases C(PLCs),their importance for producing microorganisms us well us the potential of their use for industrial purposes.Methods:PLC from Bacillus cereus(B.cereus) D101 was selected as an example of Gram-positive PLCs and PLC from Pseudomanas aeruginosa(P.aeruginosa) D183 of Gram-negative ones.Enzymes were partially purified by ammonium sulfate precipitation followed by membrane dialysis.Partially purified preparations were used to study effect of different factors on activities as well as in substrate specificity tests which were conducted using a turbidimetric assay method.Results:Maximum activity was at pH 7 and 8 and 40 ℃ for P.aeruginosa PLC,and pH 8-10 and 37 ℃ for B.cereus PLC.Both PLCs were inhibited by Pi at 5 mM or higher,whereas,PLC from B.cereus only was inhibited by EDTA.Activity of P.aeruginosa PLC was not affected by removing Zn^(2+) ions from reaction mixture or their replacement with Ca^(2+),Ba^(2+),Mg^(2+) or Mn^(2+)ions.Vis-a-vis,activity of B.cereus PLC was found to be metal ion dependent PLCs from both isolates were relatively thermostable and showed maximum affinity toward phosphatidylcholine.Sphingomyelin and phosphatidylethanolamine were not good substrates and phosphatidylinositol,phosphatidylserine,phosphatidylglycerol and cardiolipin could be considered nonsubstrates.Conclusions:Human body physiological conditions could favor activity of P.aeruginosa and B.cereus PLCs.These enzymes may participate in phosphate scavenging and virulence of producing isolates but not in autolysis.PLCs from both isolates are potential candidates for industrial use.

Rubber Seed Kernel as Potent Solid Substrate for the Production of Lipase by Pseudomonas aeruginosa Strain BUP2

This study explored the utility of flours of rubber seed, coconut and groundnut kernels, and de-oiled cakes of coconut and groundnut as solid substrate for the production of lipase by Pseudomonas aeruginosa strain BUP2 (MTCC No. 5924), a novel bacterium reported from the rumen of Malabari goat. Various proportions (10%, 20%, 30%, 40% or 50%) of flours or cakes were prepared (w/v) with BUP medium (pH 4, 5, 6, 7 or 8), and incubated at different temperature (25°C, 28°C, 30°C or 32°C) for 24 to 96 h. The samples were assayed for lipase activity at 24 h intervals. The rubber seed flour (20%)-BUP medium supported the maximum lipase production (871 U/gds) at 48h incubation (pH 6, 28°C), followed by ground nut flour (398 U/gds), while ground nut cake supported the least lipase production (244 U/gds). From this, it is evident that the cheaply available rubber seed is an efficient substrate for the production of lipase, irrespective of its known demerit that it contains the limarin, a toxin;in fact, we could not detect limarin in the fermented matter. Thus, the utility of rubber seed for the production of a costly enzyme is reported from a novel rumen bacterium, which would be advantageous for rubber farmers.

Antibiotic resistance pattern of Pseudomonas aeruginosa wound isolates among Chinese burn patients:A systematic review and meta analysis

Objective:To investigate the resistance profiles to antimicrobial agents of wound-isolated Pseudomonas(P.)aeruginosa among Chinese burn patients.Methods:Electronic databases and manual search were used to identify eligible studies published since 2010.The objectives were pooled resistance rates for eleven common antimicrobial agents,estimated by a random-effects model.Subgroup analyses were conducted by stratifying the studies into three four-year periods based on year of isolation.Results:A total of 35 studies were included.Gentamicin had the highest pooled resistance rate(56%,95%CI 48%-64%),while meropenem had the lowest pooled resistance rate(29%,95%CI 20%-40%).There was an increasing trend of resistance to common antimicrobial agents of wound-isolated P.aeruginosa over a span of twelve years(2009-2020).There remained the highest risk of gentamicin resistance over time in China.Subgroup analyses indicated significantly higher resistances to ceftazidime and levofloxacin from 2017 to 2020.Conclusions:Enhanced resistance to common antimicrobial agents in wound-isolated P.aeruginosa presents a challenge in burn wound management in China's Mainland.Effective stewardship programs should be established based on corresponding resistance profiles,thereby optimizing treatment options for hospitalized burn patients.

Efficacy of Pudilan Xiaoyan Oral Liquid in the treatment of pneumonia induced by drug-resistant Pseudomonas aeruginosa

Background:Pudilan Xiaoyan Oral Liquid(PDL)is a Chinese patent medicine with notable pharmacological properties,including anti-inflammatory and antibacterial effects.Drug-resistant Pseudomonas aeruginosa infection is a common and refractory bacterial infection in clinical practice.Due to its high drug resistance,it brings great challenges to treatment.This study aimed to assess the therapeutic efficacy of PDL in a murine model of pneumonia induced by drug-resistant Pseudomonas aeruginosa.Methods:Three different doses of PDL(11 mL/kg/d,5.5 mL/kg/d,2.75 mL/kg/d)were used to observe lung tissue pathology and inflammatory cytokine levels in pneumonia mouse models induced by multidrug-resistant Pseudomonas aeruginosa(MDR-PA).Additionally,the protective efficacy of PDL against mortality in infected mice was evaluated using a death model caused by MDR-PA.Finally sub-MIC concentration of levofloxacin was used to induce drug-resistant mice pneumonia model to evaluate the role of PDL in reversing drug resistance.Experimental data are expressed as mean±standard deviation.Statistical significance was determined by one-way analysis of variance followed by Tukey’s multiple-comparisons test.Results:Treatment effect of PDL on MDR-PA pneumonia:the medium and small doses of PDL can significantly reduce the lung index of multi-drug resistant bacteria infected pneumonia model mice(P<0.05),the lung index inhibition rates for these groups were 55.09%and 58.43%,and improve the degree of lung tissue lesions of mice;The expression of serum cytokines keratinocyte chemoattractant,tumor necrosis factor-αand monocyte chemoattractant protein-1 could be decreased in the three dosage groups of PDL(P<0.01).PDL treatment not only lowered the mortality but also extended the survival duration in mice infected with MDR-PA.It was found after sub-MIC concentration of levofloxacin induced resistance of Pseudomonas aeruginosa to pneumonia in mice.Compared with the model group,the lung index of mice in high and medium PDL doses was significantly reduced(P<0.05),with inhibition rates of 32.16%and 37.73%,respectively.Conclusion:PDL demonstrates protective effects against MDR-PA infection pneumonia,notably decreasing serum inflammatory factor levels.It shows promise in mitigating antibiotic resistance and offers potential for treating pneumonia resulting from Pseudomonas aeruginosa resistance.

A rapid, simple, and sensitive immunoagglutination assay with silica nanoparticles for serotype identification of Pseudomonas aeruginosa

An agglutination test based on colored silica nanoparticles(colored SiNps) was established to detect serotypes of Pseudomonas aeruginosa. Monodisperse colored SiNps were used as agglutination test carriers. The colored SiNps were prepared through reverse microemulsion with reactive dyes, sensitized with 11 kinds of mono-specific antibodies against P. aeruginosa, and denoted as IgG-colored SiNps. Eleven kinds of IgG-colored SiNps were individually mixed with P. aeruginosa on a glass slide.Different serotypes of P. aeruginosa could be identified by agglutination test with evident agglutination. The P. aeruginosa could be detected in a range from 3.6×10^5 to 3.6×10^12 cfu mL^–1. This new agglutination test was confirmed to be a specific,sensitive, fast, easy-to-perform, and cost-efficient tool for the routine diagnosis of P. aeruginosa.

Resistant patterns of Pseudomonas aeruginosa in a Malaysian teaching hospital

Objective:Pseudomonas aeruginosa is an opportunistic pathogen and the leading cause of nosocomial infections. Currently a notable increase in the prevalence of multidrug-resistant P.aeruginosa worldwide has been reported in hospitalized patients and was associated with high morbidity and mortality.Methods:A retrospective laboratory based analysis regarding the spectrum and distribution of P.aeruginosa from a wide range of clinical samples in Hospital Universiti Sains Malaysia since January 2003 to December 2007 was done.Results: Altogether,there were 2 308 clinical isolates analyzed.The main sources of P.aeruginosa were from swab,respiratory,urine and blood specimens which accounted for 28.2%,21.8%,13.2%and 12.8% respectively.Results showed significant reduction in percentage of resistant towards three antibiotic namely ciprofloxacin,ceftazidime and imipenem.However the percentage of pan-resistant P.aeruginosa increased steadily over these years.Conclusion:This data is helpful to the clinician in guiding the choice of appropriate antibiotic to treat P.aeruginosa infection.At the same time,it warrants a more aggressive infection control activity to be implemented to control the spread of pan resistant strain in this centre.

Distribution of extended-spectrum β-lactamase genes in antibiotic-resistant strains of Pseudomonas aeruginosa obtained from burn patients in Ahvaz, Iran

Objective: To evaluate the drug susceptibility profiles and the frequency of beta-lactamase encoding genes in Pseudomonas aeruginosa (P. aeruginosa) obtained from burn patients. Methods: Totally 93 non-duplicate clinical isolates of P. aeruginosa were recovered from burn patients of Taleghani Burn Hospital of Ahvaz. Antibiotic susceptibility testing was conducted by disk diffusion method according to the CLSI 2017 recommendations. PCR assay was performed by to find beta-lactamase encoding genes. Results: In this study, most clinical specimen was obtained via wound swabs [65 (69.9%)], followed by blood [14 (15.1%)] and biopsy (7 (7.5%))Forty-two (45.16%) patients were male and 51(54.84%) were female. High resistance was observed for most of antibiotics especially for gentamicin and ciprofloxacin (Up to 85%), whereas the highest susceptibility was reported for colistin (100.0%), followed by ceftazidime (66.7%). According to PCR results, 16.1% (15), 9.7% (9) and 14.0% (13) of isolates carried blaDHA, blaVEB and blaGES genes, respectively. It also revealed that the blaVEB gene was found to coexist within 2 isolates (2.2%). Conclusions: Antibacterial resistance is high among P. aeruginosa isolates. Colistin is highly active against multi-drug resistant P. aeruginosa isolates. Antimicrobial susceptibility testing can confine indiscriminate uses of antibiotics and resistance increase, and can improve management of treatment.

Comparison of inhibitory effect between DL-tryptophan and lactoferrin on Pseudomonas aeruginosa biofilm formation in wound dressing

Objective: To compare the inhibitory effect between DL-tryptophan and bovine lactoferrin on biofilm formed by isolated Pseudomonas aeruginosa strains. Methods: The study was carried out on 40 patients suffering from surgical site infection. Wound pus was collected using sterile swabs after isolation, and identified by common bacteriological methods. Isolated Pseudomonas aeruginosa strains were grown on biofilm enhancing materials, and then the inhibitory effects of different concentrations of DL-tryptophan and lactoferrin were tested using scanning electron microscopy and microtitre plate methods. Results: There was no significant difference in the inhibitory effect between DL-tryptophan and lactoferrin at 0.5 mg/mL. While in concentration of 1 mg/mL and 2 mg/mL, tryptophan showed more significant inhibitory effect than lactoferrin. Conclusions: Both DL-tryptophan and bovine lactoferrin have inhibitory effect on Pseudomonas aeruginosa biofilm formation in a dose dependent manner, and the inhibitory effect of DL-tryptophan is stronger.

Relationship Study between the Alkaline Protease Production and the Growth Phases of <i>Pseudomonas aeruginosa</i>Isolated from Patients

This study was conducted in Diyala University Laboratories collaboration with the Directorate of Diyala Health. Occurrence of Pseudomonas aeruginosa was investigated in 161 samples from different clinical sources included Swabs from wounds, burns, ear, eye and samples from Urine and sputum which were collected from patients. Depending on the cultural and micro features and biochemical tests 49 isolated items of this bacteria have been diagnosed and all the isolates showed the proteolytic activity by using skim milk agar through forming clear zone around the growing colonies, and tested the isolates ability of alkaline protease production by quantitative methods, the local isolation P. aeruginosa AP3 had been selected based on the higher productivity of enzyme comparing to other isolates and thus it was used in the current study. Studied the relationship between the production of alkaline protease enzymes and growth phases of P. aeruginosa to determine the time of the enzyme production and the results showed that the local isolation P. aeruginosa AP3 began production of the enzyme in the later stages of the log phase and increased production significantly in the stationary phase reaching amaximum after 48 hours as estimated the enzyme activity 159.2 units/ml in the farm leaky and keep the enzyme fully functional almost in the stationary phase.

Effect of Antibiotic Consumption on Resistance of <i>Pseudomonas aeruginosa</i>Isolated from Lebanese Patients with Emphasis on MBL Production

The relationship between antibiotic consumption and resistance has been widely evaluated. Pseudomonas aeruginosa is one of the most important opportunistic pathogens in the nosocomial setting, and its resistance to antibiotics is increaseing. Production of metallo-β-lactamases (MBLs) is currently the most fearful resistance mechanism due to the potential of dissemination. This study aimed to evaluate the correlation between antibiotic consumption (expressed in DDD/100 bed days) and resistance (expressed in % of isolates and patients) in different time periods for P. aeruginosa between 2006 and 2009 at Saint George Hospital University Medical Center (SGH-UMC), Beirut. Pearson correlation coefficients (r) were calculated and linear regression was performed. Detection of MBL-producing Imipenem resistant P. aeruginosa (IRPA) isolates between 2008 and 2009 was performed using three MBL screening methods: MBL Etest?, Imipenem/EDTA combined disk test and EDTA disk potentiation with four cephalosporins. The modified Hodge test was also performed. From 2006 till 2009, there was a trend of increasing resistance of P. aeruginosa to all antibiotics, and the highest % of resistance was for Ofloxacin. Concerning resistance expressed by isolates, high correlation coefficients resulted among Imipenem, Ciprofloxacin and Tazobactam consumption and resistance to these agents in the same year correlation;Ceftazidime and Ofloxacin consumption and resistance in the next year correlation;Gentamicin and Ofloxacin consumption and the change in resistance (ΔR). Concerning resistance expressed by patients, results were similar except for Ceftazidime and Ofloxacin correlation in the next year correlation. In MBL screening, three isolates gave accordance among 4 methods which showed a positive result. The correlation between antibiotic consumption and resistance is highly dependent on the kind of antibiotic, the organism and the time of correlation. Various MBL screening phenotypic methods on one isolate can increase accuracy and eliminate false positive and negative results.

Antimicrobial Resistance Profiles and Clonal Relatedness of <i>Pseudomonas aeruginosa</i>Strains Recovered from Wounds Infections of Outpatient Population Presenting in a Rural Hospital in Kenya

Pseudomonas aeruginosa is a leading cause of hospital infections and is intrinsically resistant to most antibiotics. Emergence of multidrug resistant (MDR) strains has been reported in the world and poses a great challenge in the management of infections associated with this species. While a substantial amount of research has been done on strains from most of other infection caused by this species in developed countries, little is known about the susceptibility profiles of strains recovered from African countries in general and Kenya in particular. Furthermore, there is paucity of data regarding strain, phenotype and genetic diversity of strains recoverable from wounds among patients in Kenya. The possible risk factors for acquisition of MDR strains and possible factors that could fuel clonal expansion in hospital and community settings remain undetermined. This cross-sectional study conducted in Tigoni Hospital, a rural area in Central Kenya sought to determine risk factors associated with carriage of MDR Pseudomonas aeruginosa in wounds among rural population. We also analyzed antimicrobial resistance profiles among these isolates. Prevalence of P. aeruginosa in wounds was 28% with 85 isolates recovered from wounds of 299 participants. Most antimicrobial resistance prevalence was recorded towards Ceftazidime (64%) and Cefepime (52%) while Piperacillin-tazobactam was the most effective antimicrobial agent with a resistance prevalence rate of 20%. Resistance towards new classes of aminoglycosides such as Gentamicin was at 45% while that towards Amikacin was at 40%. Compared to other related studies, relatively lower resistance towards Ciprofloxacin (25%) and Meropenem (40%) were recorded. Some of the risk factors identified for carriages of MDR strains were self-medication (p: 0.001, C.I: 3.01 - 8.86, O.R: 5.17) and non-completion of dosage (p: 0.12, C.I: 0.9 - 2.5, O.R: 1.5).

Comparative Study of Synergistic Effects of Antibiotics with Triangular Shaped Silver Nanoparticles, Synthesized Using UV-Light Irradiation, on <i>Staphylococcus aureus</i>and <i>Pseudomonas aeruginosa</i>

In the present work, a comparative study of antibacterial activity and synergistic effects of triangular silver nanoparticles in combination with two standard antibiotics is discussed for Staphylococcus aureus and Pseudomonas aeruginosa. A green route was developed to synthesise silver nanoparticles in which silver oxalate was taken as precursor, black tea leaves extract as surfactant and chitin as a stabilizing agent. A grey coloured colloidal solution of silver nanoparticles was obtained which was characterized by using various techniques like X-ray diffractometer (XRD), transmission electron microscopy (TEM) and UV-visible spectroscopy. Anti-bacterial studies gave approximately equal inhibition zones for both the combinations which states that silver nanoparticles are to be equally effective and synergistic effects were clearly observed in case of P. aeruginosa.

Preliminary Study on the Antibacterial Activity of Six Medicinal Plants against Two Naso-Pharyngeal Pathogens—Streptococccus pyogenes and Pseudomonas aeruginosa

Objective: The objective is to study the antibacterial activity of six medicinal plants against two naso-pharyngeal pathogens and determination of total phenol contents in ethanol extracts of those plants. Methods: Different serial concentrations (0.05 g/mL, 0.1 g/mL, 0.2 g/mL, 0.4 g/mL) of ethanolic and acetone extracts of Piper nigrum L. (Piperaceae), Ocimum sanctum Linn., Plectranthus amboinicus L. (Lamiaceae), Ayapana triplinervis M.Vahl. (Asteraceae), Cinnamomum zeylanicum L. (Lauraceae), Allium schoenoprasum Linn. (Liliaceace) were evaluated for the antibacterial activity using disc diffusion method against gram positive Streptococcus pyogenes and gram negative Pseudomonas aeruginosa. The extracts were prepared from different parts of the plants. The total phenol content was estimated using folin-ciocaltau reagent in catechol equivalents. Results: Majority of the extracts had inhibitory effect against the tested bacteria at different concentrations. In ethanol extracts, Plectranthus amboinicus exhibited the maximum zone of inhibition (14 mm) at 0.05 g/mL concentration against Streptococcus pyogenes, and Ocimum sanctum showed highest zone of bacterial inhibition (19 mm) at 0.05 g concentration against Pseudomonas aeruginosa. In acetone extracts, Piper nigrum had the maximum zone of bacterial inhibition (17 mm) in 0.4 g/mL concentration against Streptococcus pyogenes and Cinnamomum zeylanicum and Allium schoenoprasum exhibited the highest zone of bacterial inhibition (0.4 g/mL) against Pseudomonas aeruginosa. The ethanol extract of Plectranthus amboinicus contained the highest amount of phenol (0.8 mg/mL) and Allium schoenoprasum contained the lowest amount (0.62 mg/mL). In acetone, Cinnamomum zeylanicum contained highest phenol content (0.78 mg/mL). Conclusion: All these investigations pave way to the molecular modeling of the lead phyto compounds present in the studied plants, and also in finding out their biochemical action in various metabolic pathways and reactions of infection.

A Nursing Case Report: The Laryngectomy Patient Secondary to <i>Pseudomonas aeruginosa</i>Pneumonia with Conscious Disturbance

The paper presents a description of the experience of the nursing for the Pseudomonas aeruginosa pneumonia patient with partial laryngectomy. The nursing of Pseudomonas aeruginosa pneumonia, conscious disturbance, electrolyte disorder, affection supports and mental nursing was provided in the process of the postoperative treatment. Our experience may provide useful insight for the nursing of laryngectomy patients secondary to pneumonia with conscious disturbance. A deeper knowledge about improving the quality of clinic special nursing for the partial or total laryngectomy patient is necessary, with the development of modern medical technologies and medicine.

Investigation of Pseudomonas aeruginosa Resistance Pattern against Antibiotics in Clinical Samples from Iranian Educational Hospital

Pseudomonas aeruginosa (P. aeroginosa) is one of the opportunistic pathogens, which is the main cause of prevalent hospital infections worldwide. The aim of this study was to determine the prevalence of antibiotic resistance pattern against P. aeroginosa from clinical samples in our population. This study was performed during March 2009 to September 2011. During this period 233 clinical isolated samples from hospital patients were examined. In these studies, different strains of P. aeroginosa were isolated from samples, then microbiologically tested. Bacterial susceptibility was performed by the disc-diffusion tests with Kirby Baur disc diffusion tests in Muller-Hinto environment. Our results showed maximum antibiotic resistance (99.5%) of P. aeruginosa against Trimetoprime Solfametoxasole and Ciprofloxacin (55.33%), Amikacin (61%), Imipenem (33%), which were identified as the most effective antibiotics in this study. In conclusion, indeed most Pseudomonas aeruginosa strains infections are treated as soon as possible due to their severe resistance against antibiotics. So, we have to apply an accurate antibiotic treatment discipline, according to the finding, based on antibiogram, in order to prevent its spread and also, monitoring and optimization of antimicrobial use should be considered carefully.

Characterization of Imipenem Unsusceptible Pseudomonas Aeruginosa Isolates from Inpatients without Carbapenem Treatment

Objective To identify the risk factors for imipenem resistance development and transmission of clinical Pseudomonas aeruginosa isolates.Methods Thirty-seven imipenem unsusceptible Pseudomonas aeruginosa isolates collected from patients in absence of carbapenem treatment were characterized by antimicrobial susceptibility test,pulsed field gel electrophoresis(PFGE)and carbapenem resistant mechanism analysis.Results Before the collection of imipenem unsusceptible Pseudomonas aeruginosa isolates,the average time of patients treated with more than one antimicrobial(20.0±9.5 days,n=16)was significantly longer than those treated with only one antimicrobial(12.6±4.4 days,n=21;t-test,Welch,t=-2.9004,P<0.01).And 32 isolates showed resistance to more than 3 classes of antimicrobials.Six PFGE clusters were identified and 26 isolates were grouped into one dominant cluster(C2).An ISpa1328 sequence insertion in oprD was detected in 33 isolates and the function of efflux was observed in all 37 isolates in the presence of a wide spectrum efflux inhibitor.Conclusions Our data demonstrated that exposure to non-carbapenem drug classes,especially fluoroquinolones andβ-lactams,may be important risk factors for the spread of carbapenem resistant Pseudomonas aeruginosa.