Comparative efficacy of hospital disinfectants against nosocomial infection pathogens.

BACKGROUND: Due to the increasing rate of hospital-acquired infections, it is essential to select appropriate disinfectant agents. In this study, the efficacy of hospital disinfectants against nosocomial infection pathogens was compared. METHODS: High level disinfectants (Steranios 2%, Deconex HLDPA, and Microzed Quatenol) were tested for their antibacterial effects by determining their minimum inhibitory (MIC) and minimum bactericidal concentrations (MBC) against Enterococcus faecalis ATCC 29212 and Burkholderia cepacia ATCC 10673. RESULTS: E. faecalis, as gram-positive bacterium, was more susceptible to high level disinfectants compared to gram-negative B.cepacia. The MIC = MBC values of 2% Steranios, Deconex HLDPA and Microzed Quatenol against E. faecalis and B.cepacia were 0.31, 9.77, 2.2 mg/L and 9.8, 78.13, 70.31 mg/L, respectively. CONCLUSIONS: According to the findings of this study, the most effective disinfectants against both E. faecalis and B.cepacia were Steranios 2%, Microzed Quatenol, and Deconex HLDPA in order. Considering the importance of these bacterial strains in healthcare-associated infections, the use of these effective disinfectants is recommended in the hospitals.

Evaluation of anti-bacterial effects of nickel nanoparticles on biofilm production by Staphylococcus epidermidis.

BACKGROUND AND OBJECTIVES: Staphylococcus epidermidis produces biofilm by extracellular polysaccharides, causing bacterial adherence to different surfaces. Anti-microbial effects of nickel nanoparticles on some bacterial strains such as S. aureus and Escherichia coli have been determined in limited studies. The aim of the present study is to examine the inhibitory effect of nickel nanoparticles on biofilm formation using clinical isolates of S. epidermidis and its hemolytic effect on human red blood cells. MATERIALS AND METHODS: Twenty two S. epidermidis isolates were collected and identified by standard microbiological methods. Microtiter plate method was used to determine the biofilm production in bacterial isolates. The amounts of biofilm formation by isolates in the presence of 0.01, 0.05, 0.1, and 1 mg/mL concentrations of nickel nanoparticles were measured. Hemolytic activity of different concentrations of nickel nanoparticles was measured on human RBC suspensions. RESULTS: Twenty isolates were strong, and two isolates were moderate biofilm producers. Biofilm formation significantly decreased in the presence of 0.05, 0.1, and 1 mg/mL of nickel nanoparticles (p<0.05). Although in the presence of 0.01 mg/mL of nickel nanoparticles, decrease in biofilm formation was observed but it was not statistically significant (p=0.448). Slight hemolytic activity was seen in the presence of nickel nanoparticles. CONCLUSION: In this study, the ability of biofilm production was demonstrated for all clinical isolates of S. epidermidis. On the other hand, the lowering effects of nickel nanoparticles on biofilm formation were observed.

Eradication of methicillin resistant S. aureus biofilm by the combined use of fosfomycin and ß-chloro-L-alanine.

BACKGROUND AND OBJECTIVES: Biofilm formation is an important virulence factor for methicillin-resistant Staphylococcus aureus (MRSA). Fosfomycin is a borad-spectrum antibiotic with inhibitory effects on biofilm production and ß-Chloro-L-alanine (ß-CLA) is an amino acid analog. The aim of this study was to determine effect of the combination of fosfomycin and ß-CLA on biofilm production by MRSA isolates. Also, the clonal relatedness of the isolates was evaluated. MATERIALS AND METHODS: To determine the ability of biofilm production by 42 MRSA isolates, microtiter plate method was used. Antibacterial activities of fosfomycin and ß-CLA were investigated by determining MICs and MBCs. Antibiofilm activities were measured in the presence of sub-MIC concentrations of fosfomycin, ß-CLA or a combination of both. RAPD-PCR was used for investigating the clonal relationship between isolates by the two specific primers. RESULTS: 21.4% of isolates were strong and 5% were moderate biofilm producers. The effect of fosfomycin plus ß-CLA treatment on biofilm production was significantly different from non-treated, fosfomycin and ß-CLA groups (p=0.00, 0.004 and 0.000 respectively). RAPD-PCR analysis revealed that the RAPD1 primer had more discriminatory power. The Sizes of RAPD-PCR bands ranged from 150 bp to 1500 bp and the number of bands varied from 1 to 13. CONCLUSION: Clonal relatedness of isolates showed that the majority of biofilm producing isolates had identical pattern and only three isolates showed more than 80% similarity. The combination of fosfomycin and ß-CLA could be introduced as an excellent mixture for eradication of MRSA biofilms in vitro.

Methicillin-resistant Staphylococcus aureus nasal carriage between healthy students of medical and nonmedical universities.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a challenge for public health, and community-acquired (CA) infections seem to be increasing among people in different areas. METHODS: A total of 700 healthy student volunteers residing in dormitories of universities in Urmia, Iran, were enrolled in this study. After identification of the isolates, antibiotic susceptibility, presence of mecA and pvl genes, and staphylococcal cassette chromosome mec (SCCmec) typing were evaluated. RESULTS: Nasal screening identified 137 (19.6%) carriers of S aureus, and 18 (13.14%) were MRSA isolates. The antimicrobial susceptibility patterns of isolates revealed high resistance to penicillin (93.4%). All isolates were sensitive to vancomycin. The SCCmec typing showed that most MRSA strains belonged to SCCmec type IV (n = 14; 77.8%). Only 1 (5.56%) MRSA isolates carried the pvl gene. CONCLUSIONS: Our findings revealed the relatively high frequency of S aureus nasal carriers and the advent of multidrug resistance among these isolates. Most MRSA isolates were SCCmec type IV; the transfer of such MRSA strains from carriers to other individuals in crowded living conditions such as dormitories can act as a risk factor for outbreak of CA MRSA and is a serious threat for the study groups.

Effect of Echinophora platyloba DC. essential oil and lycopene on the stability of pasteurized cream obtained from cow milk.

The present study was carried out to enhance shelf life of pasteurized cream using Echinophora platyloba essential oil (EEO) and lycopene. For this purpose, two concentrations of EEO (0.10% and 0.50%) and lycopene (20 and 50 ppm) alone and together as combinations were added in pasteurized creams and analyzed for microbial characteristics, sensorial properties and lipid stability during storage at 4 ˚C and 25 ˚C for 14 days. Results of microbial and chemical analyses of experimental pasteurized creams showed that pasteurized creams treated with combinations of the EEO and lycopene in their higher concentrations had the best microbial and chemical properties and the most stability than control during storage (p < 0.05). Results of sensorial evaluation demonstrated that all treatments had favorable overall acceptability, even though, the best sensorial properties were observed in creams with combinations of EEO and lycopene in their lower concentrations. Therefore, based on the results of the present study, application of EEO and lycopene as natural preservatives is especially recommend in high fat dairy products such as butter and cream.

An Association Study between INSR/NsiI (rs2059806) and INSR/PmlI (rs1799817) SNPs in Women with Polycystic Ovary Syndrome from West Azerbaijan Province, Iran.

BACKGROUND: It has been demonstrated that insulin signaling pathway related genes have important roles in polycystic ovary syndrome (PCOS) risk. The goal of present investigation was to assess the potential association between INSR/NsiI (rs2059806) and INSR/PmlI (rs1799817) SNPs and PCOS. METHODS: 50 women with PCOS and 47 normal controls entered the study. NsiI and PmlI SNPs in the INSR gene were determined by RFLP-PCR. RESULTS: INSR/NsiI (rs2059806) SNP GG, GA, AA, G and A genotypic and allelic frequencies were 45(90%), 5(10%), 0(0%), 95(95%) and 5(5%) in cases and 41 (87.2%), 6(12.8%), 0(0%), 88(93.6%) and 6(6.38%) in controls, respectively. INSR/ PmlI (rs1799817) SNPs resulted in three genotypes of CC, CT, and TT with C and T alleles. The frequencies of PmlI (rs1799817) SNPs in the INSR gene were 37(37%) and 63(63%) in cases, also 39(41.49%) and 55 (58.51%) in controls regarding T and C alleles. The frequencies of PmlI (rs1799817) SNPs in the INSR gene were 4(8%), 29(58%), and 17(34%) in cases, also 5(10.64%), 29(61.7%), and 13(27.66%) in controls regarding TT, TC, and CC genotypes, respectively. CONCLUSION: The present study as the first investigation of its own kind in Iranian Azeri Turkish women, reported no association between NsiI (rs2059806) and PmlI (rs1799817) SNPs in the INSR gene and PCOS risk.

Molecular Genetic Analysis of the Variable Number of Tandem-Repeat Alleles at the Phenylalanine Hydroxylase Gene in Iranian Azeri Turkish Population.

BACKGROUND: The variable numbers of tandem-repeat (VNTR) alleles at the phenylalanine hydroxylase (PAH) gene have been used in carrier detection and prenatal diagnosis in phenylketonuria families. This study was carried out to analyze VNTR alleles at the PAH gene in Iranian Azeri Turkish population. METHODS: In this study, 200 alleles from general population were studied by PCR. RESULTS: The frequencies of VNTR alleles were 45%, 46%, 2%, 3%, 1%, and 3% in studied group regarding 3, 8, 9, 11, 12, and 13 repeat copies, respectively. Statistically significant differences were not found between expected and observed frequencies of VNTR genotypes (P > 0.05). CONCLUSIONS: VNTR alleles with three and eight repeats were frequent, and the VNTR alleles with 13 repeats showed 3% frequency in the tested group. This study is the first report on tested population genetic structure using VNTR alleles at the PAH gene.

Chemical composition and in vitro antibacterial activity of essential oil and methanol extract of Echinophora platyloba D.C against some of food-borne pathogenic bacteria.

Echinophora Platyloba D.C as a medicinal plant is used for preservation of foods and treatment of many diseases in different regions of Iran. The present study was undertaken to determine the chemical composition and investigation of the antibacterial effects of essential oil as well as methanol extract from aerial part of Echinophora Platyloba D.C against S. aureus, L. monocytogenes, S. Thyphimurium and E. coli. Chemical analysis using gas chromatography and mass spectrophotometry (GC/MS) showed that ocimene (26.51%), 2,3-Dimethyl-cyclohexa-1,3-diene (9.87%), alpha-pinene (7.69%) and gamma-dodecanolactone (5.66%) were dominant components of essential oil and the main constituents of methanol extract were o-Cymene (28.66%), methanol (8.50%), alpha-pinene (7.42%) and gamma-decalactone (5.20%). The essential oil showed strong antimicrobial activity against tested bacteria, whereas the methanol extract almost remained inactive against gram-negative bacteria. The most sensitive bacteria to essential oil and extract of Echinophora Platyloba D.C were L. mono-cytogenes and S. aureus. Minimum inhibitory concentration (MIC) values of essential oil against L. monocytogenes and S. aureus were 6250 and 12500 ppm, respectively. MIC of methanol extract against S. aureus and L. monocytogenes was 25000 ppm. Therefore, purifying and evaluation of antibacterial effects of the active substances of the essential oil and methanol extract of this plant for future application as antibacterial agents and food preservatives to combat pathogenic and toxigenic microorganisms is recommended.

Vitamin D Receptor TaqI Gene Variant in Exon 9 and Polycystic Ovary Syndrome Risk.

BACKGROUND: Polycystic ovary syndrome (PCOS) is known as a metabolic disorder. The results of recent studies implied that vitamin D receptor (VDR) genetic variants may impact PCOS and insulin resistance in women with PCOS. The aim of the present study was to determine the VDR TaqI gene variant in exon 9 (T/C) (rs731236) in normal controls and patients with PCOS for the first time in Iranian Azeri women. MATERIALS AND METHODS: In this case control study between April 2011 and June 2012, a total of 76 women aged 18-40 years (38 patients with PCOS and 38 healthy women as normal controls) participated. Genotypes of VDR TaqI in exon 9 (T/C) (rs731236) were determined using the PCR-RFLP method. RESULTS: The frequencies of VDR TaqI T anc C alleles were 0.605 and 0.395 in cases and 0.697 and 0.303 in controls. Also, the genotypic frequencies of VDR TaqI were 16) (42.11), 14(36.84), and 8(21.05) in cases, and 17(44.74), 19(50), and 2(5.26) in controls for TT, TC and CC genotypes respectively. There was no difference in genotype and allele frequencies between PCOS and controls (p value>0.05) with the exception of the CC genotype (p value=0.04). CONCLUSION: This report, a first of its own kind in Iranian Azeri patients, suggests that the CC genotype of VDR TaqI in exon 9 (rs731236) is associated with PCOS.