Fabrication and antimicrobial properties of novel meropenem-honey encapsulated chitosan nanoparticles against multiresistant and biofilm-forming Staphylococcus aureus as a new antimicrobial agent.

BACKGROUND: Honey exhibits a broad spectrum of antibacterial activity against Gram-positive and Gram-negative bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) ones. Chitosan (Cs) is a mucoadhesive polymer that also has antibacterial properties. Special attention has been paid to the design of polymeric nanoparticles (NPs) as new nano drug delivery systems to overcome bacterial resistance and its problems. OBJECTIVES: The aim of the present study is to synthesize Cs-meropenem NPs with/without honey as an antibiofilm and antibacterial agent to inhibit Staphylococcus aureus. METHODS: This study synthesized meropenem and honey-loaded Cs nanogels and subsequently characterized them by Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FTIR), and DLS-zeta potential. Using the broth microdilution and crystal violet assays, the antibacterial and antibiofilm activity of meropenem and honey-loaded Cs nanogel, free meropenem, free honey, and free Cs NPs were investigated in vitro against MRSA strains. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) was also used to test the cytotoxicity of several Cs-NPs compound against the HEK-293 regular cell line. RESULTS: The average size of meropenem and honey-Cs-NPs was reported to be 119.885 nm, and encapsulation efficiency was 88.33 ± 0.97 with stability up to 60 days at 4°C. The NPs showed enhanced antibiofilm efficacy against S. aureus at sub-minimum inhibitory concentrations. Additionally, the cytotoxicity of meropenem and honey-encapsulated Cs against the HEK-293 normal cell line was insignificant. CONCLUSIONS: Our findings suggested that meropenem and honey-Cs-NPs might be potential antibacterial and antibiofilm materials.

Epitope mapping of Acinetobacter baumannii outer membrane protein W (OmpW) and laboratory study of an OmpW-derivative peptide.

Outer membrane protein W (OmpW) is a less-known A. baumannii antigen with potential immunogenic properties. The epitopes of this protein are not well-identified yet. Therefore, in the present study, B- and T-cell epitopes of A. baumannii OmpW were found using comprehensive in silico and partially in vitro studies. The T-cell (both class-I and class-II) and B-cell (both linear and conformational) epitopes were predicted and screened through many bioinformatics approaches including the prediction of IFN-γ production, immunogenicity, toxicity, allergenicity, human similarity, and clustering. A single 15-mer epitopic peptide containing a linear B-cell and both classes of T-cell epitopes were found and used for further assays. For in vitro assays, patient- and healthy control-derived peripheral blood mononuclear cells were stimulated with the 15-mer peptide, Phytohemagglutinin, or medium alone, and cell proliferation and IFN-γ production assays were performed. The bioinformatics studies led to mapping OmpW epitopes and introducing a 15-mer peptide. In vitro assays to some extent showed its potency in cell proliferation but not in IFN-γ induction, although the responses were not very expressive and faced some questions/limitations. In general, in the current study, we mapped the most immunogenic epitopes of OmpW that may be used for future studies and also assayed one of these epitopes in vitro, which was shown to have an immunogenicity potential. However, the induced immune responses were not strong which suggests that the present peptide needs a series of biotechnological manipulations to be used as a potential vaccine candidate. More studies in this field are recommended.

BoHV-1 affects abortion and progesterone in dairy cows Bovine alphaherpesvirus 1 (BoHV-1) seropositivity, progesterone levels and embryo loss of 30-day-old pregnant dairy cows in Zagros Industrial Dairy Farm in Shahrekord: Examination and analysis.

BACKGROUND: Bovine alphaherpesvirus 1 (BoHV-1) is a serious disease with severe negative economic effects on the global cattle sector, especially in Iran. OBJECTIVE: This cross-sectional study was carried out to examine the seroprevalence and associated risk factors of BoHV-1 infection with progesterone levels and embryo death in 30-day pregnant dairy cattle at Zagros Industrial Dairy Farm in Shahrekord, Iran. METHODS: Between December 2017 to February 2018, blood samples were obtained from 60 dairy cow herds. To determine whether BoHV-1 was present, serum samples were examined using the ELISA for serum antibodies. To find progesterone (P4) in blood, the progesterone ELISA test was used. RESULTS: 96.7 % of sera tested positive for BoHV-1 antibodies, according to the findings. Additionally, 60.34 % of blood samples that tested positive had an experience of abortion and significantly more inseminations that resulted in pregnancy, consistent with findings from other studies conducted in Iran and other nations. CONCLUSIONS: Since this study is the first to document the risk factor for BoHV-1 infection in Shahrekord, Iran, we could infer that the virus is extensively dispersed in this area.

Two peptides derivate from Acinetobacter baumannii outer membrane protein K as vaccine candidates: a comprehensive in silico study.

BACKGROUND: The lack of appropriate vaccines is an obstacle to the effective management of A. baumannii infections. Peptide vaccines offer an attractive and promising preventive strategy against A. baumannii. OBJECTIVE: In this study, we identified specific T cell epitopes of A. baumannii outer membrane protein K (OMPK) using comprehensive bioinformatics and detailed molecular docking analysis. METHODS: Both class-I and class-II T cell epitopes of A. baumannii OMPK were predicted by three tools namely IEDB, SYFPEITHI, and ProPred. The predicted epitopes were shortlisted based on several analyses including prediction scoring, clustering, exclusion of human similarity, considering immunogenicity and cytokine production, and removal of toxic and/or allergen epitopes. The epitopic peptides with high prediction scores and appropriate properties containing both class-I and class-II T cell epitopes were selected. Two of these class I/II epitopic peptides were chosen for molecular docking studies and assessing their physicochemical properties as vaccine candidates. RESULTS: The results showed many T-cell epitopes of OMPK that could be evaluated for possible immunogenicity. Two of these epitopes (containing both class-I and II epitopes) had high prediction scores, were predicted by several tools, attached to several HLAs, and had the best docking score. They had different physicochemical properties and were conserved among Acinetobacter species. DISCUSSION: We identified the A. baumannii OMPK high immunogenic class-I and class-II T cell epitopes and introduced two promising high immunogenic peptides as vaccine candidates. It is recommended to perform in vitro/in vivo investigation of these peptides to determine their true efficacy and efficiency.

Prevalence of Salmonella Typhimurium and Salmonella Enteritidis isolated from poultry meat: virulence and antimicrobial-resistant genes.

Salmonellosis, a zoonotic disease, is one of the leading causes of foodborne illness worldwide. It is responsible for most infections caused by consumption of contaminated food. In recent years, a significant increase in the resistance of these bacteria to common antibiotics has been observed, posing a serious threat to global public health. The aim of this study was to investigate the prevalence of virulent antibiotic-resistant Salmonella spp. strains in Iranian poultry markets. A total of 440 chicken meat samples were randomly selected from meat supply and distribution facilities in Shahrekord and tested for bacteriological contamination. After culturing and isolating the strains, identification was performed using the classical bacteriological method and PCR. To determine antibiotic resistance, a disc diffusion test was performed according to the recommendations of the French Society of Microbiology. PCR was used to detect resistance and virulence genes. Only 9% of the samples were positive for Salmonella. These were Salmonella typhimurium isolates. All Salmonella typhimurium serotypes tested positive for the rfbJ, fljB, invA and fliC genes. Resistance to TET, cotrimoxazole, NA, NIT, piperacillin/tazobactam and other antibiotics was found in 26 (72.2%), 24 (66.7%), 22 (61.1%) and 21 (58.3%) isolates, respectively. The sul1, sul2 and sul3 genes were present in 20, 12 and 4 of 24 cotrimoxazole-resistant bacteria, respectively. Chloramphenicol resistance was found in six isolates, but more isolates tested positive for the floR and cat two genes. In contrast, 2 (33%) of the cat three genes, 3 (50%) of the cmlA genes and 2 (34%) of the cmlB genes were all positive. The results of this investigation showed that Salmonella typhimurium is the most common serotype of the bacterium. This means that most of the antibiotics commonly used in the livestock and poultry industries are ineffective against most Salmonella isolates, which is important for public health.

Frequency distribution of virulence factors and antibiotic resistance genes in uropathogenic Proteus species isolated from clinical samples.

One of the most common causes of urinary tract infections (UTIs) is Proteus species. Because there is little information on the pathogenicity of Proteus species isolated from Iran, we assessed their virulence characteristics and antibiotic resistance in this study. In Shahrekord, Iran, 260 isolates of Proteus causing UTIs were identified from patients. Polymerase chain reaction for gene amplification was used to determine virulence features and antibiotic resistance gene distribution in uropathogenic Proteus spp. After biochemical and molecular analysis, 72 (27.69%) of the 260 collected samples were recognized as Proteus mirabilis, and 127 (48.84%) specimens were Pr. vulgaris in both male and female forms. A significant interaction effect between Pr. mirabilis and Pr. vulgaris infections and the sex of patients was seen in both the male and female groups. No statistically significant difference was observed between Pr. mirabilis infection and season in different year seasons. However, in different seasons of the year, a statistically significant difference was observed between infection with Pr. vulgaris in autumn and other seasons. There was a considerable difference between Pr. mirabilis and Pr. vulgaris infections at different ages in various age groups. As people aged, infections occurred more frequently. Fim,pap,kspMT, and set1 genes had the highest expression in both Pr. vulgaris and Pr. mirabilis. Also, the highest rate of antibiotic resistance of Pr. vulgaris and Pr. mirabilis is attributed to the high expression of aac(3)-IV,tet(A), and blaSHV genes. In conclusion, identifying these genes as the key controllers of Proteus virulence factors might help with better infection management.

Relationship between Biofilm Formation and Antibiotic Resistance and Adherence Genes in Staphylococcus aureus Strains Isolated from Raw Cow Milk in Shahrekord, Iran.

The production of biofilms by S. aureus contributes significantly to treatment failures. The present study aims to establish the relationship between biofilm formation and antibiotic resistance and adhesion genes in Staphylococcus aureus strains isolated from raw cow milk in Shahrekord, Iran. A total of 90 samples of raw cow's milk were collected. Presumptive S. aureus strains were obtained using Baird-Parker plates after enrichment in tryptone soy broth, and final colonies were selected from brain heart infusion. Additional tests such as coagulase were done, and the identification was confirmed by the detection of the aroA gene. Biofilm producing strains were screened using a spectrophotometry method applied to microplates. Crystal violet staining was used to quantify the formation of biofilm. An antibiotic susceptibility test was performed using the Kirby-Bauer disc diffusion method. PCR was used to detect several biofilm and antibiotics resistance related genes. The chi-square test and Fisher's exact test were used to establish a statistically significant relationship between biofilm reaction and antibiotic resistance (p value <0.05). Results show a moderate (38.88%) recovery rate of S. aureus in milk and 65.71% of the isolates were strong biofilm producers. Antibiotic susceptibility tests show an alarming rate of resistance to beta-lactam antibiotics, especially penicillin (100%), ampicillin (91.42%), and oxacillin (71.42%). This finding correlates with antibiotic resistance gene detection, in which the gene blaZ was most found (71.42%), followed by mecA and Aac-D (42.85%). Detection of biofilm-related genes shows that all the genes targeted were found among S. aureus isolates. Statistical tests show a significant correlation between biofilm production and antibiotic resistance in S. aureus. This study revealed that there is a significant correlation between biofilm production and antibiotic resistance in S. aureus isolated from raw milk. These results highlight the need for regular surveillance of the occurrence of S. aureus strains in milk and milk products in Iran.

Prevalence, antimicrobial resistance, virulence gene profile and molecular typing of Campylobacter species isolated from poultry meat samples.

BACKGROUND: Campylobacter jejuni and Campylobacter coli are the most significant Campylobacter species responsible for severe gastrointestinal disorders. Raw poultry meat is considered a source of Campylobacter transmission to the human population. OBJECTIVES: The present study was aimed to assess the prevalence rate, antibiotic resistance properties, virulence characters and molecular typing of C. jejuni and C. coli strains isolated from raw poultry meat samples. METHODS: Three hundred and eighty raw poultry meat samples were collected and analysed for the presence of Campylobacter spp. using the microbial culture. Species identification was done using the Polymerase Chain Reaction. Disk diffusion was developed to assess the antimicrobial resistance pattern of isolates. The distribution of virulence and antimicrobial resistance genes was determined by PCR. Enterobacterial Repetitive Intergenic Consensus-PCR was used for molecular typing. RESULTS: Campylobacter species were isolated from 6.25% of examined samples. C. jejuni and C. coli contamination rates were found to be 57.44% and 48.14%, respectively. C. jejuni strains harboured the highest resistance rate against serythromycin (42.59%), ampicillin (38.88%), ciprofloxacin (33.33%), chloramphenicol (31.48%) and tetracycline (31.48%). C. coli isolates harboured the highest resistance rate against ampicillin (73.07%), ciprofloxacin (73.07%), erythromycin (65.38%) and chloramphenicol (50%). AadE1 (44.44%), blaOXA-61 (42.59%) and tet(O) (35.18%) were the most commonly detected resistance genes in C. jejuni and cmeB (34.61%) and blaOXA-61 (34.61%) were the most commonly detected among C. coli strains. The most frequent virulence factors among the C. jejuni isolates were flaA (100%), ciaB (100%), racR (83.33%), dnaJ (81.48%), cdtB (81.48%), cdtC (79.62%) and cadF (74.07%). The most frequent virulence factors among the C. coli isolates were flaA (100%), ciaB (100%), pldA (65.38%) and cadF (61.53%). CONCLUSIONS: The majority of C. jejuni and C. coli strains had more than 80% similarities in their ERIC-PCR pattern, which may show their common source of transmission. The role of goose and quebec meat samples as reservoirs of virulent and antimicrobial resistant Campylobacter spp. was determined.

Molecular characterization of Enterobacter aerogenes isolated from urinary tract infections in Iran.

The prevalence of multidrug-resistant Enterobacter aerogenes strains in UTIs is increasing. Therefore, the purpose of this study was to examine the mechanisms of resistance in Enterobacter aerogenes strains isolated from the urinary tract of infected patients. To achieve this goal, 786 urine samples from Shahrekord, Iran, were collected from June 2019 to February 2020. After isolating and identifying E. aerogenes samples, antibiotic susceptibility testing was done on the strains using Kirby-Bauer's disk diffusion method. The biofilm formation assays were performed to study the link between antibiotic resistance and biofilm formation and virulence genes. As a result, amongst the 786 urine samples, 50 strains were identified as E. aerogenes. The lowest rate of resistance was observed with imipenem (30%). This study also reports that all the strains of E. aerogenes are biofilm producers, with 50% of isolates producing a large amount, 30% a moderate amount, and 20% a small amount of biofilm. 42% were identified in the phenotypic study of ESBLs. In the PCR test, (64%) produced broad-spectrum beta-lactamases. Prevalence of qnrC, qnrB, qnrA, tetA, tet B, acc(3)IIa, acc(2)IIa, ant(2)Ia and Sul1 in strong producing isolates reported 100%, 80.95%,% 58.14, 87.5%, 81.58%, 86.67%, 82.14, 81.48% and 90% respectively. In the statistical analysis based on the chi-square test, a statistically significant relationship was reported between qnrA, qnrB, tetA, tetB, Sul1, ant(2)Ia, ant(3)I, aac(3)II, and biofilm formation. Resistance to cephalothin, ceftriaxone, cefotaxime and ceftazidime were reported 40%, 34%, 30% and 30%, respectively. Out of 50 Enterobacter aerogenes, 32 isolates (64%) were identified in the phenotypic study of ESBLS, prevalence of blaCTX-M, blaTEM and blaSHV reported 30%, 20% and 14% respectively. There is a significant relationship between resistance to ceftriaxone and blaCTX-M. Prevalence of csgA, ybtS, markD, rmpA, csgD and fimH in strong biofilm formation isolates reported 84%, 83.33%, 80%, 80%, 80% and 66% respectively. The chi-square test showed a statistically significant relationship between biofilm production and resistance genes fimH, csgA, csgD, ybtS, and mrkD. The findings of this study indicate that the ability to produce biofilms is associated with the increase of antibiotic resistance and virulence genes. These agents enable bacteria to produce biofilms that ultimately lead to colonization and bacterial survival in the body.

Genotyping, antibiotic resistance and prevalence of Arcobacter species in milk and dairy products.

BACKGROUND: Arcobacter spp. has been considered an emerging foodborne pathogen and a hazard to human health. The dairy chain has been isolated from different sources; nevertheless, data on Arcobacter occurrence in raw milk and dairy products in Iran are still scant. OBJECTIVE: The present study investigates the prevalence, antimicrobial susceptibility and the presence of virulence genes of Arcobacters species isolated from milk and dairy products. METHODS: Then, a total of 350 raw milk samples and 400 dairy product samples were collected from dairy supply centers in Isfahan, Iran. Presumptive Arcobacter strains were obtained by enriching samples in Oxoid Arcobacter enrichment broth (AEB) followed by the filtration of enrichment product through 0.45-µm pore size membrane filters laid onto non-selective blood at 30°C under microaerophilic conditions. Molecular identification of Arcobacter cryaerophilus and A. butzleri was performed by Polymerase chain reaction (PCR) amplification of the 16S rRNA gene, followed by sequencing. The disc diffusion method was used to determine the antimicrobial susceptibility of isolates. Targeted resistance and virulence genes were detected using multiplex PCR. RESULTS: The results show a low recovery rate of Arcobacter spp. in milk. Arcobacters were found in all types of milk, except raw camel milk, but were absent from all dairy products. Arcobacter butzleri was the predominant species in raw milk. Detection of virulence genes shows that all virulence genes targeted were found among A. butzleri, and six (cadF, cj1349, irgA, mviN, pldA, tlyA) were found among A. cryaerophilus. All A. butzleri strains and some A. cryaerophilus strains isolated from milk were resistant to amoxicillin-clavulanic acid and tetracycline. All A. cryaerophilus isolates from milk were susceptible to gentamycin, streptomycin, erythromycin and ciprofloxacin. The distribution of resistance genes in Arcobacter strains in milk shows that all isolates carried tet(O) and blaOXA-61 genes. CONCLUSIONS: In conclusion, the results indicate a low recovery rate of Arcobacter spp. in milk and milk products. However, a significant number of Arcobacter strains with putative virulence genes may be potential pathogens for humans and an overall increase in Arcobacter resistance to first-line antibiotics. These results highlight the need for regular surveillance of Arcobacter strains in milk and milk products in Iran.

Novel NAD-independent Avibacterium paragallinarum: Isolation, characterization and molecular identification in Iran.

BACKGROUND: Infectious coryza (IC) is an invasive upper respiratory disease caused by Avibacterium paragallinarum that affects birds, particularly chickens. The objective of this study is to isolate, characterize and molecularly identify the bacterium A. paragallinarum in poultry birds, as well as to determine its antibiotic sensitivity and resistance. METHODS: A total of 10 chickens from four different Iranian farms with typical IC symptoms were used in this study. The nasal swabs were streaked onto chocolate agar plates and blood agar plates and incubated at 37°C in 5% CO2 for 24 to 48 h. As part of the identification of bacteria, bacteriological observations and polymerase chain reaction (PCR) testing are conducted. The antibiotic sensitivity tests were also performed using the disk diffusion method against A. paragallinarum and the prevalence in different farms was determined. RESULTS: By using biochemical assays and PCR analyses, seven strains of A. paragallinarum were isolated from samples of four chicken farms with typical IC clinical signs. Most isolates (4/7) showed the typical requirement for nicotinamide adenine dinucleotide (NAD) and an enriched CO2 atmosphere for growth. Three of the seven strains of A. paragallinarum were found to be novel NAD-independent under anaerobic conditions. There was one biochemical biovar identified in terms of carbohydrate fermentation patterns, although changes in maltose carbohydrate fermentation patterns were detected in the No. 5 strain. All isolates were sensitive to gentamicin and spectinomycin. Three novel NAD-independent strains (Nos.1, 5 and 7) were found to be multidrug-resistant (MDR) and resistant to at least three classes of antibiotics. There was greater antibiotic resistance in the three NAD-independent isolates than in normal NAD-dependent bacteria. CONCLUSION: By discovering NAD-independent forms of A. paragallinarum, these species have a greater range than previously believed. A clear, cautious approach should be taken in diagnosing and possibly controlling IC.

Molecular characterization and antimicrobial resistance of Enterococcus faecalis isolated from seafood samples.

BACKGROUND: Enterococcus faecalis is considered an opportunistic foodborne pathogen. The present study aimed to assess the prevalence, antimicrobial resistance, virulence characters, and molecular typing of E. faecalis strains isolated from seafood samples. METHODS: Two hundred and seventy-six seafood samples were collected. E. faecalis was isolated from samples using bacterial culture. Furthermore, the disk diffusion assessed their antimicrobial resistance. Also, the distribution of virulence factors was determined using polymerase chain reaction (PCR) assay. Random amplified polymorphic DNA (RAPD) method was used for their molecular typing. RESULTS: Fifty-six of 276 (20.2%) seafood samples were contaminated with E. faecalis. Fish harboured the highest contamination rate (30.0%). Isolates harboured the highest resistance rate towards oxacillin (100%), tetracycline (100%), erythromycin (100%), cefoxitin (89.2%), cefazolin (87.5%), trimethoprim-sulfamethoxazole (85.7%), rifampin (69.6%), clindamycin (69.6%), and gentamicin (64.2%) antimicrobials. Efa (100%), ebpA (89.2%), ebpB (58.9%), ebpC (53.5%), and esp (51.7%) were the most commonly detected virulence factors among E. faecalis isolates. RAPD-PCR analysis showed 11 different molecular clusters considering the closeness of more than 80%. CONCLUSION: Seafood samples were considered reservoirs of virulence and resistant E. faecalis strains. Different molecular clusters of isolates may reflect their diverse sources of contamination.

Genotyping of Chlamydia abortus using multiple loci variable number of tandem repeats analysis technique.

BACKGROUND: The correlation between various factors (geographical region, clinical incidence, and host type) and the genomic heterogeneity has been shown in several bacterial strains including Chlamydia abortus. METHODS: The aim of this study was to survey the predominant types of C. abortus strains isolated from ruminants in Iran by the multiple loci variable number of tandem repeats (VNTR) analysis (MLVA) method. C. abortus infection was evaluated in a total of 117 aborted fetuses by real-time PCR. The isolation was done via the inoculation of the positive samples in chicken embryo and the L929 cell line. Genotyping was carried out by MLVA typing technique. RESULTS: Forty samples (34.2%) were detected with C. abortus infection; however, chlamydial infection in ruminants of Charmahal/Bakhtiari (3 bovines and 35 sheep) was higher than that of Khuzestan (2 sheep). All MLVA types (MT1-MT8) were detected in the collected samples from Charmahal/Bakhtiari but only 2 types (MT1 and MT3) were reported in samples from Khuzestan. The main MT type was MT1 (32% of aborted fetuses). Although in this study only 9 cow samples were investigated, they possessed similar clusters to those obtained from sheep (MT1 and MT6). Variation of type in sheep samples (MT1 to MT8) was more than that of bovine samples (MT1, and MT6). CONCLUSION: By this research revealed that C.abortus was responsible for a significant percentage of ruminant abortion in two studied regions. The main MT type was MT1 (32% of aborted fetuses) and also 7 different genotypes were involved in infections. So it is concluded that diversity in C.abortus genotyping is high in two regions.

Prevalence of Virulence Genes and Antibiotic Resistance Pattern in Enterococcus Faecalis Isolated from Urinary Tract Infection in Shahrekord, Iran.

BACKGROUND: This study aims to specify the antimicrobial resistance pattern and virulence genes of Enterococcus faecalis isolated from urinary tract infections in Shahrekord, Iran. METHODS: Urine samples of 1000 people suspected of having urinary tract infections referred to Shahrekord medical diagnostic laboratories were examined. Biofilm assays were performed by microtiter plate test through reading the OD490. Polymerase Chain Reaction (PCR) was applied to study the virulence factors. RESULTS: Enterococcus faecalis was detected in 60 samples. After performing microbiological tests, all samples were positive in the molecular analysis. Strong, moderate and weak biofilm reactions reported 66.67%, 25%, and 8.33% respectively. The most resistance reported to cotrimoxazole, vancomycin and amikacin and the lowest resistance to nitrofurantoin (8.33%) was reported. Statistical analysis with Fisher's exact test showed a statistically significant relationship between biofilm production and resistance to cotrimoxazole, vancomycin and cefotaxime. Prevalence of efe A, ace, gel E, esp, cyl M, agg, cyl A and cyl B in strong biofilm formation isolates was reported 100%, 87.5%, 82%, 62.5%, 55%, 37.5% 25% and 22.5% respectively. There was a significant relationship between the frequency of efa A and strong biofilm reaction. CONCLUSION: The presence of E. faecalis strains resistant to co-trimoxazole and vancomycin and present of some virulence factors is alarming the researchers. Since antibiotic resistance genes are probably transmitted among enterococci, and Staphylococci, controlling infections made by enterococci as well as the appropriate administration of antibiotics could treat the nosocomial infections effectively.

Insight into population structure of Mycobacterium tuberculosis isolates in the multiethnic province of Alborz, Iran.

BACKGROUND AND OBJECTIVES: Genetic diversity of Mycobacterium tuberculosis clinical isolates from tuberculosis patients in the multiethnic province of Alborz, Iran was assessed. MATERIALS AND METHODS: A total of 17 isolates in the period of 2012-2013 were collected and subjected to a Multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) consisted of 6 variable numbers of tandem repeats (VNTRs) including ETR-A, ETR-B, ETR-C, ElTR-D, ETR-E, ETR-F, 5 Mycobacterial Interspersed Repetitive Units including MIRU10, MIRU16, MIRU26, MIRU39, MIRU40, and 1 Queen University of Belfast locus, QUB11. RESULTS: This classified all isolates into 17 distinct MIRU-VNTR types, a reflection of a highly heterogenic population. Within the 12 used VNTR loci, ten proved highly or moderately discriminant according to the calculated HGDI scores. No cluster of isolates was identified in the study panel, giving a clustering rate of 0%, several events of SVL (N=5) and DVL (N=4) and TVL (N=3) were detected. CONCLUSION: The greater heterogeneity observed here by MLVA-VNTR analysis is most likely due to limited background data in the study region rather than a genuine more heterogeneous population compared to other provinces of the country.

Pomegranate peel extract inhibits internalization and replication of the influenza virus: An in vitro study.

OBJECTIVE: Influenza virus, which is associated with high level of morbidity and mortality, has been recently considered a public health concern; however, the methods of choice to control and treat it are limited. Our previous study showed anti-influenza virus activity of pomegranate peel extract (PPE). In this study, the mechanism through which PPE acts against influenza virus A/Puerto Rico/8/34 (H1N1; PR8) was investigated. MATERIALS AND METHODS: Ethyl alcohol extract of pomegranate (Punica granatum L.) peel was prepared, and the action mechanism of PPE in inhibiting influenza replication was studied by time-of-drug-addition assay, virucidal activity, RNA replication, hemagglutination inhibition assay, viral mRNA expression, and western blot analysis. RESULTS: PPE inhibited viral polymerase activity, viral RNA replication, and viral protein expression but could not affect hemagglutination inhibition and virucidal activity. According to time-of-drug-addition assay results, PPE inhibited the virus adsorption and early steps of influenza replication. CONCLUSION: This study demonstrated that the antiviral effect of PPE on influenza virus is most probably associated with inhibition of viral adsorption and viral RNA transcription.

Recognition of (Sesc) for Easy Identification of Staphylococcus Epidermidis and Molecular and Phenotypic Study of Β-Lactam Resistance in Staphylococcus Epidermidis Isolates in Isfahan.

BACKGROUND: Not only is it crucial to rapidly detect Staphylococcus epidermidis (S. epidermidis) isolates from a broad range of bacteria, but recognizing resistance agents can greatly improve current diagnostic and therapeutic strategies. METHODS: The current cross-sectional study investigated 120 clinical isolates from a nosocomial S. epidermidis infection. The isolates were identified using common biochemical tests, and specific S. epidermidis surface protein C (SesC) primers were used to confirm the presence of S. epidermidis. PCR and special primers were used to detect the ß-lactamase gene (blaZ). Methicillin resistance was measured using the agar screening method and antibiotic susceptibility was measured by disk diffusion. RESULTS: 100 samples were characterized as S. epidermidis using a phenotypic and genotypic methods. From the 100 specimens examined, 80% contained blaZ. According to agar screening, 60% of isolates were methicillin-resistant. S. epidermidis isolates demonstrated the highest resistance to penicillin (93%) and the highest sensitivity to cefazolin (39%). CONCLUSION: The increased resistance to ß-lactam antibiotics in S. epidermidis isolates is alarming, and certain precautions should be taken by healthcare systems to continuously monitor the antimicrobial pattern of S. epidermidis, so that an appropriate drug treatment can be established.

Prevalence and phenotypic pattern of antibiotic resistance of Acinetobacter baumannii isolated from different types of raw meat samples in Isfahan, Iran.

Resistant Acinetobacter baumannii isolates are not only known as opportunistic nosocomial bacteria but may also be regarded as emerging bacterial contaminants in foods of animal origins. The present investigation was done to assess the prevalence and antibiotic resistance pattern of A. baumannii isolated from different types of raw meat samples. One hundred and ninety-four raw meat samples were collected and cultured for A. baumannii isolates. Culture-positive bacteria were also approved using the loop-mediated isothermal amplification (LAMP) technique. The disc diffusion method was used for antibiotic susceptibility testing. Out of 194 raw meat samples, 39 (20.10%) were positive for A. baumannii isolates. Ovine raw meat was the most commonly contaminated samples (32.14%). All of the culture-positive A. baumannii isolates were also approved using the LAMP assay. A. baumannii isolates harboured the highest prevalence of resistance against gentamicin (87.17%), tetracycline (79.48%), erythromycin (74.35%), azithromycin (66.66%), ciprofloxacin (58.97%), trimethoprim/sulphamethoxazole (56.41%) and rifampin (51.28%). The lowest prevalence of resistance was found against imipenem (17.94%) and chloramphenicol (28.20%). Raw bovine, ovine, caprine, camel and poultry meat samples were considered as the important sources of isolates resistant to some of the categories of antimicrobials used to treat infections caused by A. baumannii. Further studies are required to find the exact role of resistant A. baumannii isolates in the dissemination of antibiotic resistance to human population.

Virulence factors and antibiotic resistance properties of the Staphylococcus epidermidis strains isolated from hospital infections in Ahvaz, Iran.

BACKGROUND: Resistant Staphylococcus epidermidis strains are considered to be one of the major causes of human clinical infections in hospitals. The present investigation was done to study the pattern of antibiotic resistance and the prevalence of virulence and antibiotic resistance genes amongst the S. epidermidis strains isolated from human hospital infections. METHODS: One hundred hospital infectious samples were collected and S. epidermidis strains were identified using culture and biochemical tests. Isolated strains were subjected to disk diffusion and PCR. RESULTS: Forty-six out of 100 hospital infectious samples (46%) were positive for S. epidermidis. S. epidermidis strains harbored the highest prevalence of resistance against penicillin (95.65%), tetracycline (91.30%), erythromycin (82.60%), cefazolin (78.26%), and trimethoprim-sulfamethoxazole (73.91%). All S. epidermidis strains had resistance against at least three different types of antibiotics, while the prevalence of resistance against more than seven types of antibiotics was 17.39%. AacA-D (69.56%), tetK (56.52%), mecA (45.65%), msrA (39.13%), and tetM (39.13%) were most commonly detected antibiotic resistance genes. The prevalence of vatC (4.34%), ermA (8.69%), vatA (8.69%), vatB (13.04%), ermC (13.04%), and linA (10.86%) were lower than other detected antibiotic resistance genes. ClfA (32.60%), agrIII (17.39%), and etB (13.04%) were the most commonly detected virulence factors. CONCLUSIONS: The presence of virulent and multi-drug resistance S. epidermidis strains showed an important public health issue in hospitals.

Phenotypic and molecular characterization of antimicrobial resistance in Trueperella pyogenes strains isolated from bovine mastitis and metritis.

BACKGROUND: Trueperella pyogenes is one of the most clinically imperative bacteria responsible for severe cases of mastitis and metritis, particularly in postpartum dairy cows. The bacterium has emergence of antibiotic resistance and virulence characters. The existing research was done to apprise the phenotypic and genotypic evaluation of antibiotic resistance and characterization of virulence factors in the T. pyogenes bacteria of bovine mastitis and metritis in postpartum cows. METHODS: Two-hundred and twenty-six bovine mastitic milk and 172 uterine swabs were collected and transferred to laboratory. Samples were cultured and T. pyogenes isolates were subjected to disk diffusion and DNA extraction. Distribution of virulence and antibiotic resistance genes was studied by PCR. RESULTS: Thirty-two out of 226 (14.15%) mastitic milk and forty-one out of 172 (23.83%) uterine swab samples were positive for T. pyogenes. Isolates of mastitic milk harbored the highest prevalence of resistance toward gentamicin (100%), penicillin (100%), ampicillin (90.62%), amoxicillin (87.50%) and trimethoprim-sulfamethoxazole (87.50%), while those of metritis harbored the highest prevalence of resistance toward ampicillin (100%), amoxicillin (100%), gentamicin (97.56%), penicillin (97.56%) and cefalexin (97.56%). AacC, aadA1, aadA2 and tetW were the most generally perceived antibiotic resistance genes. All bacteria harbored plo (100%) and fimA (100%) virulence factors. NanP, nanH, fimC and fimE were also the most generally perceived virulence factors. CONCLUSIONS: All bacteria harbored plo and fimA virulence factors which showed that they can use as specific genetic markers with their important roles in pathogenicity of T. pyogenes bacteria. Phenotypic pattern of antibiotic resistance was confirmed by genotypic characterization of antibiotic resistance genes.