Biofilm generation and antibiotic resistant profile of extensive and multidrug resistant Pseudomonas aeruginosa from burn patients in Ahvaz: A cross-sectional study.

Background and Aims: Multidrug and extensive drug-resistant Pseudomonas aeruginosa was extracted from burn patients referring to burn centers in southwest Iran so that biofilm generation and antibiotic resistance could be investigated. Methods: A specific primer was used to confirm all our considered 110 P. aeruginosa culture-positive reports on 345 burn patients. The resistance of P. aeruginosa to seven antibiotics and Colistin with minimum inhibitory concentration (MIC) was assessed. Biofilm formation was assessed by the phenotypic study of specimens under Congo red agar and microtiter plate assays. Results: One hundred and 10 clinical P. aeruginosa isolates taken from burn wound infections were validated. Among P. aeruginosa isolates, Piperacillin, Ceftazidime, Maeropenem, Gentamycin, and Gatifloacin had the highest resistance to antibiotics, while Ticarcillin-Clavulanic acid and Ceftolozane-Tazobactam showed the least resistance. MICs were then evaluated via the E test. Seven isolates were resistant to colistin. Colistin reference MICs for multidrug-resistant P. aeruginosa prevalence was 38%, while it was 22% for extensively drug-resistant (XDR) P. aeruginosa. One P. aeruginosa was pandrug-resistant (PDR). Under Congo red agar test, 66 isolates (67%) formed biofilms and black colonies, whereas 44 isolates (50%) had red colonies. In MTP, 76% formed biofilm. 40%, 32%, 21% of the isolates were strong, moderate, and weak biofilm formers, respectively, while 43% did not form biofilms. Conclusion: The P. aeruginosa resistance to antimicrobial agents has largely challenged the control of the infection. Accordingly, a higher resistance occurred when the isolates were transferred to the patients. Less than 50% P. aeruginosa samples generated strong biofilms. Consequently, hygienic measurements are essential to inhibit P. aeruginosa transmission to hospitalized patients.

High prevalence of multidrug-resistant Pseudomonas aeruginosa carrying integron and exoA, exoS, and exoU genes isolated from burn patients in Ahvaz, southwest Iran: A retrospective study.

Background: Pseudomonas aeruginosa as an opportunistic pathogen produces several virulence factors. This study evaluated the relative frequency of exoenzymes (exo) A, U and S genes and integron classes (I, II, and III) among multi-drug-resistant clinical P. aeruginosa isolates from burn patients in Ahvaz, southwest of Iran. Methods: In this cross-sectional study P. aeruginosa isolates were recovered from 355 wound samples. The antimicrobial susceptibility test was done by disk agar diffusion method on Muller-Hinton agar according to the Clinical and Laboratory Standards Institute. MDR isolates were defined if they showed simultaneous resistance to 3 antibiotics. Extensively drug-resistant was defined as nonsusceptibility to at least one agent in all but two or fewer antimicrobial categories. The presence of class I, II, and III integrons and virulence genes was determined using a PCR assay on extracted DNA. Results: Overall, 145 clinical P. aeruginosa isolates were confirmed with biochemical and PCR tests. Overall, 35% (52/145) of the isolates were taken from males and 64% (93/145) from female hospitalized burn patients. The highest resistance rates of P. aeruginosa isolates to antibiotics were related to piperacillin 59% (n = 86/145) and piperacillin-tazobactam 57% (n = 83/145). A total of 100% of isolates were resistant to at least one antibiotic. MDR and XDR P. aeruginosa had a frequency of 60% and 29%, respectively. The prevalence of integron classes I, II, and III in P. aeruginosa was 60%, 7.58%, and 3.44%, respectively. IntI was more common in MDR and XDR P. aeruginosa isolates. In addition, 70(48%) of P. aeruginosa isolates did not harbor integron genes. Besides, exoA, exoS, and exoU in P. aeruginosa had a frequency of 55%, 55%, and 56%, respectively. Conclusion: It was found that P. aeruginosa as a potent pathogen with strong virulence factors and high antibiotic resistance in the health community can cause refractory diseases in burn patients.

Application of lactobacillus casei and lactobacillus plantarum to develop dried functional apple and banana.

The goal of this research was to create dried fruits loaded with probiotic microorganisms (Lactobacillus casei and Lactobacillus plantarum). In separate bottles for each probiotic microbe, apple and banana pieces have been submerged into the impermeability solution with gentle shaking. The vacuum pressure was applied. By the conclusion of the incubation time, L. casei and L. plantarum colonies were enumerated (CFU/g). The scanning electron microscope method was applied to confirm the penetration of impregnation solutions into the intercellular spaces of fruit tissue. On day 28, the population of L. plantarum was 5 log CFU/g for apples and 5.5 log CFU/g for bananas. After storage, the number of L. casei in apples was 5 log CFU/g and 5.5 log CFU/g, respectively. L. casei was found on the surface of apple and banana tissue. After one-week, whole phenolic content of probiotic-enriched bananas and apples augmented. After storage, the antioxidant activity of all samples decreased greatly. The sensory qualities of the samples were excellent throughout storage in terms of color, quality, scent, sensitivity, chewiness, and general adequacy. As a result, dried apples and bananas infused with L. plantarum and L. casei might be a novel probiotic meal. RESEARCH HIGHLIGHTS: Dried apples and bananas infused with L. plantarum and L. casei are novel probiotic meal. After one-week, whole phenolic content of probiotic-enriched bananas and apples augmented. The sensory qualities of the samples were excellent throughout storage in terms of color, quality, scent, sensitivity, chewiness, and general adequacy.

Antimicrobial and anti-biofilm potencies of dermcidin-derived peptide DCD-1L against Acinetobacter baumannii: an in vivo wound healing model.

BACKGROUND: The global emergence of Acinetobacter baumannii resistance to most conventional antibiotics presents a major therapeutic challenge and necessitates the discovery of new antibacterial agents. The purpose of this study was to investigate in vitro and in vivo anti-biofilm potency of dermcidin-1L (DCD-1L) against extensively drug-resistant (XDR)-, pandrug-resistant (PDR)-, and ATCC19606-A. baumannii. METHODS: After determination of minimum inhibitory concentration (MIC) of DCD-1L, in vitro anti-adhesive and anti-biofilm activities of DCD-1L were evaluated. Cytotoxicity, hemolytic activity, and the effect of DCD-1L treatment on the expression of various biofilm-associated genes were determined. The inhibitory effect of DCD-1L on biofilm formation in the model of catheter-associated infection, as well as, histopathological examination of the burn wound sites of mice treated with DCD-1L were assessed. RESULTS: The bacterial adhesion and biofilm formation in all A. baumannii isolates were inhibited at 2 × , 4 × , and 8 × MIC of DCD-1L, while only 8 × MIC of DCD-1L was able to destroy the pre-formed biofilm in vitro. Also, reduce the expression of genes involved in biofilm formation was observed following DCD-1L treatment. DCD-1L without cytotoxic and hemolytic activities significantly reduced the biofilm formation in the model of catheter-associated infection. In vivo results showed that the count of A. baumannii in infected wounds was significantly decreased and the promotion in wound healing by the acceleration of skin re-epithelialization in mice was observed following treatment with 8 × MIC of DCD-1L. CONCLUSIONS: Results of this study demonstrated that DCD-1L can inhibit bacterial attachment and biofilm formation and prevent the onset of infection. Taking these properties together, DCD-1L appears as a promising candidate for antimicrobial and anti-biofilm drug development.

Effect of Helicobacter Pylori eradication on patients with ITP: a meta-analysis of studies conducted in the Middle East.

BACKGROUND: Immune thrombocytopenia (ITP) is a bleeding disorder. Helicobacter pylori is a Gram-negative bacterium that is presumed to be associated with ITP and therapeutic response of patients. To evaluate the effect of H. pylori eradication on platelet count of ITP patients, we analyzed the studies conducted on the association between H. pylori infection and response to therapy in ITP patients in Western Asia focusing on the Middle East region. METHODS: A systematic search of databases (PubMed/Medline, ISI Web of Science, Cochrane Central) and Google Scholar search engine results was conducted up until January 2020. The keywords included in the search were Helicobacter pylori and/or H. pylori, ITP and/or immune thrombocytopenia. RESULTS: Seven studies comprising a total of 228 H. pylori-infected patients (193 with successful eradication) were included in this study. The association between H. pylori eradication and ITP was expressed as odds ratios (OR) and 95% confidence intervals (CI). The findings showed that patients who received eradication treatment for H. pylori infection had significantly higher OR (OR, 8.83; 95% CI, 2.03‒38.35; P =0.004) than those in the non-eradicated group. CONCLUSION: Our results indicate a significant therapeutic effect of H. pylori eradication on the platelet count of patients with chronic ITP. Given the inherent limitations of this study, including the small number of patients, further studies with more patients are recommended.

Effects of the Consumption of Probiotic Yogurt Containing Bifidobacterium lactis Bb12 on the Levels of Streptococcus mutans and Lactobacilli in Saliva of Students with Initial Stages of Dental Caries: A Double-Blind Randomized Controlled Trial.

Dental caries, caused by oral microbiota, is one of the most common human diseases. The present study aimed to investigate the effect of consumption of probiotic yogurt containing Bifidobacterium lactis Bb12 on salivary Streptococcus mutans and lactobacilli in students with initial stages of dental caries. In this double-blind randomized placebo-controlled clinical trial, 66 students (18-30 years) with initial stages of dental caries were selected and randomly assigned into 2 groups: the intervention group received 300 g/day of probiotic yogurt and the control group received 300 g/day of conventional yogurt for 2 weeks. An unstimulated fasting saliva sample was collected pre- and post-intervention. Bacterial counting was performed for salivary S. mutans and lactobacilli. A significant reduction in salivary S. mutans and lactobacillus counts was observed in the intervention group compared to their baseline and compared to the control group. In conclusion, it is suggested that the consumption of probiotic yogurt containing B. lactis Bb12 may modify the oral biofilm.

Genetic Variations in VDR could Modulate the Efficacy of Vitamin D3 Supplementation on Inflammatory Markers and Total Antioxidant Capacity among Breast Cancer Women: A Randomized Double Blind Controlled Trial.

Background: Low levels of vitamin D are found in a great part of breast cancer women. Study subjects using vitamin D3 supplement had lower rates of cancers and fewer markers of inflammation. Additionally, recent studies demonstrate the power of vitamin D supplementation to lower inflammation and oxidative stress biomarkers associate with VDR polymorphism to reduce inflammation. This study was aimed to assess the impact of vitamin D3 supplementation on the serum concentration of inflammatory markers and antioxidant capacity with regard to VDR polymorphism in the VDR gene in breast cancer women. Methods: A randomized, double-blind, placebo-controlled trial was conducted on 56 breast cancer women. Participants were assigned to 2 treatment arms: placebo and vitamin D3 for 2 months intervention. Supplementation group received 50,000 IU of vitamin weekly. Blood samples were collected at baseline and after the intervention to measure the 25(OH) D3, TNF-α, TGF- ß and TAC. Genotyping was performed for FokI, BsmI, ApaI, and TaqI polymorphism. Results: After eight weeks supplementation, the intervention group showed a significant increase in the serum concentration of 25(OH) D3 (28±2.6 to 39±3.5; p=0.004 and TAC (48.9±13.3 to 63.5±13.3; p= 0.017). Changes in TNF-α, TGF- ß1 were not significant. Serum TAC levels of participants with the TT/Tt, Ff genotypes were more responsive to supplementation. Conclusions: Supplementation with a vitamin D3 increased the TAC in breast cancer women, although it had no effect on inflammatory markers. Serum TAC in the TT/Tt, Ff were more responsive to vitamin D supplement compared with those with the FF/ff and tt genotypes.

Emergence of High-level Gentamicin Resistance among Enterococci Clinical Isolates from Burn Patients in South-west of Iran: Vancomycin Still Working.

Enterococcus faecalis and Enterococcus faecium are among the main agents associated with nosocomial infections with high mortality in immunocompromised patients. Antibiotic resistance, especially against gentamicin and vancomycin among Enterococci , is a risk factor that could increase the morbidity and mortality rate. 179 Enterococci isolates from burn patients were included in this study. Antibiotic susceptibility testing was done using the disk diffusion test and minimum inhibitory concentration (MIC) was evaluated by agar microdilution. Vancomycin and gentamicin resistance associated genes including vanA , vanB , vanC , aac (6')-Ie aph(2''), aph(3')-IIIa and ant(4')-Ia were detected by PCR and their statistical relation with antibiotic resistance was evaluated. E. faecalis was the more prevalent strain among our local isolates and showed a higher antibiotic resistance in comparison to E. faecium . Vancomycin had a good antibacterial effect on the Enterococcus spp. isolates; however, resistance to this antibiotic and a high-level gentamicin resistance (HLGR) phenotype were observed. Among van operon genes, vanA was the most prevalent gene and among the gentamicin resistance genes, aph (3')-IIIa was more frequent. The HLGR Enterococci are a real challenge in nosocomial infections. Vancomycin is a key antibiotic to treat such infections but emergence of VRE in our region could be a real concern and, therefore, phenotypic and molecular surveillance must be considered.Enterococcus faecalis and Enterococcus faecium are among the main agents associated with nosocomial infections with high mortality in immunocompromised patients. Antibiotic resistance, especially against gentamicin and vancomycin among Enterococci, is a risk factor that could increase the morbidity and mortality rate. 179 Enterococci isolates from burn patients were included in this study. Antibiotic susceptibility testing was done using the disk diffusion test and minimum inhibitory concentration (MIC) was evaluated by agar microdilution. Vancomycin and gentamicin resistance associated genes including vanA, vanB, vanC, aac (6')-Ie aph(2''), aph(3')-IIIa and ant(4')-Ia were detected by PCR and their statistical relation with antibiotic resistance was evaluated. E. faecalis was the more prevalent strain among our local isolates and showed a higher antibiotic resistance in comparison to E. faecium. Vancomycin had a good antibacterial effect on the Enterococcus spp. isolates; however, resistance to this antibiotic and a high-level gentamicin resistance (HLGR) phenotype were observed. Among van operon genes, vanA was the most prevalent gene and among the gentamicin resistance genes, aph (3')-IIIa was more frequent. The HLGR Enterococci are a real challenge in nosocomial infections. Vancomycin is a key antibiotic to treat such infections but emergence of VRE in our region could be a real concern and, therefore, phenotypic and molecular surveillance must be considered.

Molecular Characterization of Methicillin-Resistant Staphylococcus aureus Isolates, Isolated from a Burn Hospital in Southwest Iran in 2006 and 2014.

OBJECTIVES: Incidence of methicillin-resistant Staphylococcus aureus (MRSA) is increasing every year, especially in burn patients with a high rate of morbidity and mortality. Molecular and epidemiologic studies are useful practices for understanding the relatedness of isolates in a single patient or a hospital. This study aimed at determining molecular characterizations of isolates collected in 2006 and 2014 using S. aureus-specific staphylococcal protein A (Spa) typing and Multilocus Sequence Typing (MLST) methods. MATERIALS AND METHODS: Totally, 71 MRSA isolates were collected during the last two studies (2006 and 2014) from burn patients at Taleghani Burn Centre. After confirmation, all isolates were analysed using MLST and Spa typing methods. RESULTS: We reported the emergence of Spa type t021, ST-30-IV MRSA isolates, which were PVL-positive in 14.6% of the cases and t12366, ST-8-IV isolates, which were PVL-negative in 9.8% of the cases. In 2014 study, Spa typing of MRSA isolates revealed five different spa types. Overall, in two studies, t037, ST-239, SCCmec III, and CC8 were predominant clones and they were reported in 63% of the cases. CONCLUSION: The predominance of ST-239 in this region during the last eight years is a major concern. It also has a disturbing impact on the management of staphylococcal infections. Moreover, the SCCmec type IV strain is able to disseminate rapidly in hospital environments, demanding an improvement in infection-control policy.

Antimicrobial resistance patterns and virulence factors of enterococci isolates in hospitalized burn patients.

OBJECTIVE: The objective of this study was to determine the frequency of the antimicrobial resistance and genes encoding virulence factors of enterococci isolated in hospitalized burn patients in a major burn center in Ahvaz, southwest of Iran. A total of 340 bacterial isolates were collected from the burn center from February 2014 to February 2015. The antimicrobial susceptibility and MIC of vancomycin were determined using the disk diffusion and micro-agar dilution techniques. The genus and species-specific genes, potential virulence genes, and vanA and vanB genes were detected by polymerase chain reaction. RESULTS: According to our results, out of the 340 bacterial isolates, 16.4% (n = 56) were identified as enterococci. Out of the 56 enterococcal isolates, 35 (62.5%) were Enterococcus faecalis and 21 (37.5%) were Enterococcus faecium. More than 20% (n = 5) of E. faecium demonstrated resistance to vancomycin. The gelE and asa genes were the most prevalent virulence genes in E. faecalis (48.5%) and E. faecium (43%) isolates. The emergence of vancomycin resistant E. faecium strains which have several virulence factors should be considered as a major cause of concern for burn centers. Control and management of infections induced by enterococci should be regarded as highly important in burn patients.

Correction to: Acquisition of Tn6018-3' CS regions increases colistin MICs against Acinetobacter baumannii isolates harboring new variants of AbaRs.

The published online version of this article contained a mistake. The correct affiliation of Alireza Ekrami should have been "Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran" . The authors regret this error.

Circulating 25-Hydroxy Vitamin D Relative to Vitamin D Receptor Polymorphism after Vitamin D3 Supplementation in Breast Cancer Women: A Randomized, Double-Blind Controlled Clinical Trial

Objective: The influence of vitamin D receptor (VDR) genetic variation on serum 25-hydroxyvitamin D levels [25(OH)D] after vitamin D3 supplementation remains unclear. We aimed to investigate changes of 25(OH)D in a randomized, double-blind, placebo-controlled clinical trial, according to VDR genotype, after provision of vitamin D3 to breast cancer cases for a 2-month period. Methods: Participants were assigned to two treatment arms: placebo (n = 28) and vitamin D3 supplementation (n =28). The supplementation group received 50,000 IU of vitamin D every week for 2 months. Blood samples were collected at baseline and after intervention to measure serum 25(OH)D3. Genotypes were assessed for FokI, BsmI, ApaI, and TaqI polymorphisms. Results: After eight weeks supplementation, the intervention group showed a significant increase in the serum concentration of 25 (OH)D3 (28±2.6 to 39±3.5; p=0.004). Subjects were then classified into twelve subgroups according to different VDR genotypes. Subjects with ff/Ff, TT/Tt, and Bb genotypes had significantly higher increases in serum 25(OH)D compared to those with FF, tt, and BB/bb genotypes post-intervention. Serum vitamin D3 levels with the AA genotype were lower than with aa/ Aa. No differences were found among other subgroups. Conclusion: Vitamin D3 supplementation increases serum 25(OH)D in women with breast cancer. Serum vitamin D3 in TT/Tt, ff/Ff, and Bb carriers was more responsive to vitamin D supplementation than in those with FF/ff and tt genotypes. Other subgroups might gain less from vitamin D3 supplementation.

Acquisition of Tn6018-3' CS regions increases colistin MICs against Acinetobacter baumannii isolates harboring new variants of AbaRs.

Colistin is the last hope to treat extensively drug resistance (XDR) Acinetobacter baumannii (A. baumannii) infections, but resistance to colistin is currently reported in clinical centers all over the world. Here, we studied two colistin-resistant A. baumannii isolates with a difference in minimum inhibitory concentrations (MICs) that were isolated from a single burn patient during treatment in the hospitalization period. The international clonal (IC) lineage, multilocus sequence typing (MLST), and multiple loci variable number tandem repeat (VNTR) analysis (MLVA) typing were used to characterize the relatedness of A. baumannii isolates. Lipopolysaccharides (LPS) and PmrAB system analysis by PCR sequencing, polyacrylamide gel electrophoresis (PAGE), and real-time PCR were performed to determine the intactness and probable modifications of the LPS as the main resistance mechanisms to colistin. A combination of PCR, sequencing, and restriction fragment length polymorphism (RFLP) was used for A. baumannii resistance islands (AbaR) mapping as resistance-determinant reservoirs. Two isolates were identical at all MLST and VNTR marker loci that indicated the isolates were the same strain. In comparison to colistin-heteroresistant A. baumannii strain TEH267 (MIC = 1.5 mg/L), colistin-resistant A. baumannii strain TEH273 (MIC ≥256 mg/L) acquired two genomic regions including Tn6018-topA sequence and topA sequence-3' CS in its AbaR structure containing ispA and cadA genes which, it would appear, could be associated with eightfold increase in colistin MIC. Both isolates had new variants of AbaR-like structures which could be derivatives of the typical AbaR3. According to the results of this study, AbaRs could be associated with an increase in MIC to colistin.

Plasmid borne Carbapenem-Hydrolyzing Class D ß-Lactamases (CHDLs) and AdeABC efflux pump conferring carbapenem-tigecycline resistance among Acinetobacter baumannii isolates harboring TnAbaRs.

Here we studied the prevalence and mechanisms of simultaneous resistance to carbapenem and tigecycline and accumulation of resistance determinants reservoirs in genome of Acinetobacter baumannii (A. baumannii) clinical isolates. Susceptibility of the isolates were measured to 18 antimicrobial agents. Genetic diversity of the microbial population was determined using the International Clonal lineage typing (IC typing), multiple locus VNTR analysis (MLVA) and plasmid profiling methods. To detect the AbaRs, Carbapenem-Hydrolyzing Class D ß-Lactamases (CHDLs) genes, AdeABC efflux pump genes and resistance determinants, PCR was used. Filter mating experiments were used to prove that if carbapenem resistance genes are located on conjugative plasmids or not. Among the A. baumannii clinical isolates, 40.8% were carbapenem-tigecycline resistant and in this population, 46.9% were belonging to IC I, IC II or IC III and 53.1% were IC variants. These isolates had fallen in 40 MLVA types and were harboring plasmids in multiple numbers and sizes. In this study, blaOXA-23-like was the most prevalent CHDL and conjugation analysis proved that the carbapenem resistance genes are located on conjugative plasmids. All efflux pump genes, except for adeC, were detected in all carbapenem-tigecycline resistant A. baumannii (CTRAb) isolates. Resistance determinants were distributed in both TnAbaRs and R plasmids with a shift toward the R plasmids. Emerging of carbapenem resistant A. baumannii (CRAB) with simultaneous resistance to the last line therapy including tigecycline represent emerging of extensively drug resistance (XDR) and pandrug resistance (PDR) phenotypes that would be a great threat to our public health system.

Molecular characterization of Shigella spp. isolates from a pediatric hospital in Southwestern Iran.

AIM: In This study focused on the detection of dominant clones and genetic relationship of Shigella spp. isolated from children with diarrhea in the main pediatric hospital in Ahvaz by multi-locus sequence typing (MLST) technique. BACKGROUND: Shigellosis is considered as one of the problematic bacterial infections for public health in the world. Khuzestan province in the Southwestern part of Iran is a known endemic area for infections due to Shigella. There are limited molecular epidemiological data for Shigella spp. in this area. METHODS: A total of 50 Shigella spp. were isolated from January-June 2015 based on conventional microbiology and serology tests. The Sequence types (ST) of Shigella isolates which are characterized by Enterobacterial repetitive intergenic consensus (ERIC-PCR) were detected by MLST technique. RESULTS: Among 50 Shigella isolates, a total of 31(62%), 16(32%) and 3 (6%) of Shigella isolates were identified as S. flexneri, S.sonneii, and S.boydii, respectively. Two different sequence types (ST152 and ST245) were identified in Shigella isolates. ST152 was detected in S.sonnei and ST245 in S. flexneri and S. boydii isolates. CONCLUSION: Based on MLST data, the stable and genetically linked Shigella clones are the cause of Shigella infections in children in Southwestern Iran.

Hematological and liver toxicity of anti-tuberculosis drugs.

INTRODUCTION: Tuberculosis (TB) is a major global health problem, and anti-tuberculosis drugs can cause severe adverse reactions. The aim of this study was to determine hematological and biochemical changes and associated risk factors in smear positive pulmonary tuberculosis patients undergoing treatment with standard protocols. METHODS: In a descriptive study, a total of 40 tuberculosis patients aged between 15-60 years were collected from hospitals in Khuzestan Province (Iran) from March 2013 to March 2014. The patients were treated with drugs (isoniazid, rifampicin, ethambutol, and pyrazinamide) during the initial two months, followed by isoniazid and rifampicin for the next four to six months. Activities of liver enzymes (ALT, AST, and ALP) and hematological parameters were recorded before and after treatment. Data were analyzed using paired samples t-test and Wilcoxon test by SPSS 16. RESULTS: After using drug treatments, hematological parameters (RBC, Hb, HCT, MCV, MCH, and MCHC), except platelet count, were changed significantly (p ≤ 0.001). Liver enzyme activities (ALT, AST, and ALP) were decreased significantly (p ≤ 0.001) after treatment. CONCLUSION: In this study, changes of hematological and biochemical parameters have been observed in patients with pulmonary tuberculosis. It can be concluded that the anti-tuberculosis treatment is associated with changes of hematological parameters and liver enzymes.

Characterization of Toxin-Antitoxin (TA) Systems in Pseudomonas aeruginosa Clinical Isolates in Iran.

BACKGROUND: Pseudomonas aeruginosa is among the most problematic hospital and community-acquired pathogens. Toxin-antitoxin (TA) systems are maintenance regulatory systems in bacteria and have recently been considered new targets for antimicrobial therapy. The prevalence and transcription of these systems in clinical isolates are still unknown. OBJECTIVES: The aim of this study was to characterize three types of TA systems (parDE, relBE, and higBA) among P. aeruginosa clinical isolates. MATERIALS AND METHODS: We typed our clinical isolates by ERIC-PCR (enterobacterial repetitive intergenic consensus sequence-based polymerase chain reaction) and BOX-PCR. We then investigated 174 P. aeruginosa clinical isolates from three hospitals in Ahvaz, Iran, for the presence of TA system genes, and determined whether these systems were encoded on chromosomes or plasmids by amplification of the flanking regions. RESULTS: Our results showed that in the 174 P. aeruginosa isolates, relBE and higBA were universal, but parDE was less prevalent. Both of the flanking regions of the parDE genes in all positive isolates were amplified. The flanking regions of nearly all relBE genes were amplified. Amplification was observed for the downstream sequence of every higBA locus, as well as for the region upstream of higBA, except in 14 strains. CONCLUSIONS: Based on the presence of TA systems in the majority of P. aeruginosa isolates, these could be used as a novel target for antimicrobial therapy.

Methicillin Resistant Staphylococci: Prevalence and susceptibility patterns in a burn center in Ahvaz from 2013-2014.

BACKGROUND AND OBJECTIVES: Methicillin resistance Staphylococcus aureus (MRSA) and coagulase negative staphylococci (MRCoNS) have recognized as the major cause of nosocomial infections that threat the burn patient's life. The aims of this study were to determine the frequency of MRSA and MRCoNS and their antibiotic resistance patterns among burn patients in a burn center in Ahvaz, Iran. MATERIAL AND METHODS: A total of 340 clinical specimens: (80%) wound and (20%) blood were obtained from patients in Taleghani burn hospital during February 2013-2014. Staphylococci species identification and antibiogram were performed by standard procedures using disk diffusion method. The Methicillin resistance strains were detected by Etest and PCR using mecA specific primers. RESULTS: Out of 30.2% (103) isolates that were recognized as staphylococci, 82 % (84) and 18% (19) were identified as S. aureus and coagulase negative staphylococci (CoNS) respectively. Resistance to methicillin was detected in 60% and 63% of the S. aureus and CoNS isolates respectively. Seven different antimicrobial resistance patterns observed among methicillin resistant staphylococci. The MRSA and MRCoNS strains showed closed resistance phenotypes. All the methicillin resistant isolates showed a high rate resistance to the other studied antibiotics in comparison to methicilin sensitive isolates. Vancomycin and imipenem showed the greatest effect against methicillin resistant isolates. During 8 years in the studied burn hospital, no significant changes in the methicillin resistance staphylococci frequency were detected. CONCLUSION: The presence of multi resistant MRSA and MRCoNS strains is cause of concern in burn hospitals. Vancomycin remains as a drug of choice for methicillin resistance staphylococci infections.

Bioconjugated fluorescent silica nanoparticles for the rapid detection of Entamoeba histolytica.

Rapid detection of Entamoeba histolytica based on fluorescent silica nanoparticle (FSNP) indirect immunofluorescence microscopy was evaluated. Silica nanoparticles were synthesized using Stöber's method, with their surface activated to covalently bind to, and immobilize, protein A. For biolabeling, FSNP was added to conjugated E. histolytica trophozoites with monoclonal anti-E. histolytica IgG1 for microscopic observation of fluorescence. Fluorescent silica nanoparticle sensitivity was determined with axenically cultured E. histolytica serially diluted to seven concentrations. Specificity was evaluated using other intestinal protozoa. Fluorescent silica nanoparticles detected E. histolytica at the lowest tested concentration with no cross-reaction with Entamoeba dispar, Entamoeba moshkovskii, Blastocystis sp., or Giardia lamblia. Visualization of E. histolytica trophozoites with anti-E. histolytica antibody labeled with fluorescein isothiocyanate (FITC) was compared with that using anti-E. histolytica antibody bioconjugated FSNP. Although FITC and FSNP produced similar results, the amount of specific antibody required for FITC to induce fluorescence of similar intensity was fivefold that for FSNP. Fluorescent silica nanoparticles delivered a rapid, simple, cost-effective, and highly sensitive and specific method of detecting E. histolytica. Further study is needed before introducing FSNP for laboratory diagnosis of amoebiasis.