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BACKGROUND: Enterobacter cloacae complex (ECC) including different species are isolated from different human clinical samples. ECC is armed by many different virulence genes (VGs) and they were also classified among ESKAPE group by WHO recently. The present study was designed to find probable association between VGs and antibiotic susceptibility in different ECC species. METHODS: Forty-five Enterobacter isolates that were harvested from different clinical samples were classified in four different species. Seven VGs were screened by PCR technique and antibiotic susceptibility assessment was performed by disk-diffusion assay. RESULT: Four Enterobacter species; Enterobacter cloacae (33.3%), Enterobacter hormaechei (55.6%), Enterobacter kobei (6.7%) and Enterobacter roggenkampii (4.4%) were detected. Minimum antibiotic resistance was against carbapenem agents and amikacin even in MDR isolates. 33.3% and 13.3% of isolates were MDR and XDR respectively. The rpoS (97.8%) and csgD (11.1%) showed maximum and minimum frequency respectively. Blood sample isolated were highly virulent but less resistant in comparison to the other sample isolates. The csgA, csgD and iutA genes were associated with cefepime sensitivity. CONCLUSION: The fepA showed a predictory role for differentiating of E. hormaechei from other species. More evolved iron acquisition system in E. hormaechei was hypothesized. The fepA gene introduced as a suitable target for designing novel anti-virulence/antibiotic agents against E. hormaechei. Complementary studies on other VGs and ARGs and with bigger study population is recommended.
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Antibacterianos , Enterobacter cloacae , Infecções por Enterobacteriaceae , Testes de Sensibilidade Microbiana , Fatores de Virulência , Humanos , Antibacterianos/farmacologia , Enterobacter cloacae/genética , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/isolamento & purificação , Enterobacter cloacae/patogenicidade , Infecções por Enterobacteriaceae/microbiologia , Fatores de Virulência/genética , Virulência/genética , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/genética , Enterobacter/genética , Enterobacter/efeitos dos fármacos , Enterobacter/isolamento & purificação , Masculino , FemininoRESUMO
BACKGROUND: Contribution of efflux pumps in development of antimicrobial resistance has been largely addressed in Gram negative and to a much lesser extent in Gram positive bacteria. Measuring accumulation of Hoechst (H) dye is known as a safe and rapid method for monitoring efflux activity in bacteria. Antimicrobial effects of metal nanoparticles have been attributed in part to inhibition of efflux pumps. This study aimed to first determine efflux activity in enterococci by Hoechst accumulation assay, and to second characterize the role of zinc oxide nanoparticles (ZnONPs) in inhibition of these pumps. RESULTS: Increased accumulation of Hoechst dye showed more potential of ZnONPs in efflux inhibition compared with CCCP. H33258 represented more suitability for accumulation studies in enterococci. Two to six-fold reduction in minimum inhibitory concentration (MIC) values of antimicrobial agents in the presence of ZnONPs was observed. CONCLUSIONS: Efflux activity in enterococcal strains can be measured by H33258 accumulation assay. Application of ZnONPs as an efflux inhibitor, may rejuvenate the use of conventional antimicrobial agents against these bacteria.
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Anti-Infecciosos , Nanopartículas Metálicas , Óxido de Zinco , Antibacterianos/farmacologia , Enterococcus , Testes de Sensibilidade Microbiana , Óxido de Zinco/farmacologiaRESUMO
Healthcare workers (HCWs) are proposed as the potential source of transmission of Staphylococcus aureus to hospitalized patients, especially in burn units. This study aimed to investigate S. aureus from burn wound infections and those from the nose of HCWs in terms of antibiotic resistance, the presence of Panton-Valentine leucocidin-encoding gene (pvl) and the arginine catabolic mobile element (ACME), and the ability for biofilm formation. Also, the genetic diversity of isolates was assessed using staphylococcal protein A (spa) typing and staphylococcal cassette chromosome mec (SCCmec) typing. Overall, regarding the studied factors, significant differences were found neither between isolates from patients and HCWs nor between methicillin-resistant and methicillin-susceptible isolates (except for multidrug resistance which was significantly higher in MRSA). The most frequent SCCmec types were type I and III. ACME-arcA was only detected in isolates from patients and similarly the presence of ACME-opp3 was the most prevalent in this group. The presence of common clonal complexes among patient isolates and more importantly between isolates from patients and HCWs is warning. The high prevalence of virulence factors, both in MRSA and MSSA, emphasizes the importance of MSSA in burn centers. Finding no significant difference in the presence of virulence-associated factors between isolates from patients and HCWs demonstrates the need to take HCWs into account as important reservoirs.
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Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/uso terapêutico , Unidades de Queimados , Pessoal de Saúde , Humanos , Irã (Geográfico)/epidemiologia , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/genética , Fatores de Virulência/genéticaRESUMO
OBJECTIVES: The purpose of this study was to investigate the distribution pattern of genes responsible for erythromycin and tetracycline resistance and their association with resistance phenotypes in enterococcus isolates. MATERIALS AND METHODS: Eighty-six Enterococcus faecalis and 26 E. faecium isolates were collected from 2 hospitals in Kerman, Iran. Minimum inhibitory concentration of erythromycin and tetra-cycline was determined and then genes encoding resistance to erythromycin - erm (A-C), mef, and msr - and tetracycline - tet (M), tet (O), tet (S), tet (K), and tet (L) - were investigated. RESULTS: In all resistant isolates (n = 72, 64%), high-level resistance to both tested antibiotics was found. The most prevalent erm gene was erm (B) (77.7%), followed by erm (A) (15.2%) and erm (C) (8.3%). Genes mediating erythromycin efflux were detected in 70.8% (mef) and 9.7% (msr) of resistant isolates. Regarding tetracycline, tet (M) was detected at the highest rate (50%), followed by tet (O) (31%) and tet (S) (11%). Export of tetracycline was found in 31% (tet (K)) and 12% (tet (L)) of isolates. CONCLUSION: A high prevalence of high-level resistance to both erythromycin and tetracycline was documented. Alterations at the ribosomal level was more frequently detected in erythromycin and tetracycline resistance than efflux systems. Concurrent resistance mechanisms were more involved in resistance to erythromycin than tetracycline.
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Enterococcus/efeitos dos fármacos , Enterococcus/isolamento & purificação , Eritromicina/farmacologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Tetraciclinas/farmacologia , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Enterococcus/genética , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/isolamento & purificação , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Enterococcus faecium/isolamento & purificação , Humanos , Irã (Geográfico) , Testes de Sensibilidade MicrobianaRESUMO
BACKGROUND: Combination of a cell wall-active antibiotic with an aminoglycoside confers a synergistic effect in the treatment of some severe enterococcal infections. Unfortunately, with the emergence of enterococci with high-level resistance to aminoglycosides, particularly to gentamicin, the efficacy of the synergistic combinations has decreased. In this study, high-level gentamicin-resistant (HLGR) isolates of enterococci and the diversity of the genes encoding aminoglycoside-modifying enzymes (AMEs) as well as putative clonal dissemination of HLGR isolates were investigated in a university hospital in southeastern Iran. METHODS: The minimum inhibitory concentration of gentamicin was determined and HLGR isolates were investigated for AME genes. Genetic similarity between isolates was analyzed using repetitive extragenic palindromic (rep)-Polymerase Chain Reaction (PCR) assay. RESULTS: Of 150 Enterococcus isolates, 62 isolates including Enterococcus faecalis (nâ¯= 46) and E. faecium (nâ¯= 16) were identified as HLGR. The most prevalent AME genes in both species were as follows: aph(3')-IIIa (nâ¯= 44), aac(6')-Ie-aph(2')-Ia (nâ¯= 36), and ant(4')-Ia (nâ¯= 15). The rep-PCR analysis showed clonality among E. faecalis isolates, so that 27 isolates were grouped in seven clusters representing similarity greater than 95%. CONCLUSIONS: No link between AME determinants and clusters was found. Clonal spread of HLGR isolates of E. faecalis was found within our hospital. More rigorous recommendations are required to avoid dissemination of such resistant microorganisms in the hospital setting.
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Enterococcus faecalis , Enterococcus faecium , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Gentamicinas , Humanos , Irã (Geográfico)RESUMO
BACKGROUND: The Escherichia coli sequence type 131 (ST131) is a well established clone causing significant extraintestinal infections worldwide. However, no studies have been reported the phenotypic and molecular traits of ST131 isolates in comparison to other clones of E. coli from Iran. So, we determined the differences between 69 ST131 strains collected during a one year surveillance study and 84 non-ST131 isolates, including 56 clinical fluoroquinolone resistant and 28 broiler colibacillosis isolates in terms of clonality and genetic background. RESULTS: ST131 isolates were associated with phylogroup B2 (68 out of 69 isolates, 98.4%), while clinical non-ST131 and fluoroquinolone resistant broiler isolates mainly belonged to phylogroup A. The highest virulence score was observed in ST131 clone, while they showed less diversity in virulence profiles than other clinical isolates. Almost all of the ST131 isolates (95.6%) were ExPEC and had the highest virulence scores, but their resistance scores were less than clinical non-ST131 isolates. Broiler isolates showed higher prevalence of ExPEC-associated virulence genes and CTX-M-G1/G9 resistance determinants as compared to clinical non-ST131 isolates. While blaOXA-48/NDM carbapenemases were mostly found in ST131 clone, resistance rate against ertapenem was higher among clinical non-ST131 strains. According to ERIC-based fingerprinting, the ST131 strains were more genetically similar, followed by non-ST131 and broiler isolates. CONCLUSIONS: ST131 isolates possess the ability to make a balance between clonality and extent of resistance/virulence genes content, so this phenomenon gives a fitness advantage over other E. coli clones. The broilers E. coli population poses a potential zoonotic risk which could be transmitted to the community through the food chain. A number of factors are involved in the dissemination of and infections due to ST131 clone.
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Infecções por Escherichia coli/epidemiologia , Escherichia coli/classificação , Doenças das Aves Domésticas/epidemiologia , Fatores de Virulência/genética , Animais , Proteínas de Bactérias/genética , Galinhas , Farmacorresistência Bacteriana , Ertapenem/farmacologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Infecções por Escherichia coli/veterinária , Fluoroquinolonas/farmacologia , Humanos , Irã (Geográfico)/epidemiologia , Fenótipo , Prevalência , beta-Lactamases/genéticaRESUMO
Listeria monocytogenes is a foodborne pathogen that can pose serious complications during pregnancy and neonatal infection. This study aimed to determine the frequency of L. monocytogenes infection, prevalent serotypes, and virulence genes among pregnant women and those experiencing miscarriages in Kerman, Iran. Out of 200 vaginal swabs, 4.5 and 29.5% of specimens were positive for L. monocytogenes infection as identified by culture and molecular methods, respectively. The majority of isolates from positive cultures (89%) of pregnant women resulted in stillbirth, death, and blindness. The most prevalent virulence determinants were inl B, prf A, and act A. The majority of isolates were non-typable. A history of miscarriage and gestational age are known to be significantly associated with the presence of infection. This study emphasizes the importance of initial screening for L. monocytogenes in pregnant women in Iran. Molecular methods may be useful in this process. Increasing the awareness of pregnant women could be effective in reducing pregnancy-related listeriosis.
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Listeria monocytogenes , Listeriose , Complicações Infecciosas na Gravidez , Adolescente , Adulto , Estudos Transversais , Feminino , Genótipo , Humanos , Irã (Geográfico) , Listeria monocytogenes/isolamento & purificação , Listeriose/diagnóstico , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Resultado da Gravidez , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND: The increasing incidence of antimicrobial resistance has led to research on finding new antimicrobial agents or identifying drug combinations with synergistic effects. Enterococcal infections, particularly those associated with vancomycin-resistant enterococci (VREs), are therapeutic problems. Linezolid (LZD), an oxazolidinone antibiotic, shows good activity against Gram-positive bacteria including enterococci. To avoid the emergence of linezolid-resistant subpopulations and achieve enhanced activity or bactericidal effect, the use of combined therapy has been considered. METHODS: The in vitro activity of LZD in combination with five different antibiotics was evaluated using a microdilution checkerboard method and time-kill study against 12 clinical enterococcus isolates. RESULTS: With the checkerboard method, LZD plus doxycycline (DX) had the highest frequency among all synergistic combinations. This combination and the one of LZD plus ceftriaxone (CRO) were the most frequent effective combinations against VREs. Time-kill studies using selected synergistic combinations-LZD + DX and LZD + CRO-showed an indifferent interaction. One tested combination of LZD + rifampicin showed antagonism. CONCLUSIONS: Antagonistic interactions in combinations containing LZD are rare. LZD + DX and LZD + CRO may be beneficial in the treatment of VREs. However, more time-kill studies as well as in vivo experiments are required.
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Antibacterianos , Farmacorresistência Bacteriana Múltipla , Enterococcus , Antibacterianos/farmacologia , Sinergismo Farmacológico , Quimioterapia Combinada , Enterococcus/efeitos dos fármacos , Humanos , Linezolida/farmacologia , Testes de Sensibilidade Microbiana , Enterococos Resistentes à Vancomicina/efeitos dos fármacosRESUMO
Methicillin-resistant Staphylococcus aureus (MRSA) is a global threat to public health. This study is the first report of the emergence of vancomycin-resistant MRSA in Kerman, Iran. During a period of 15 months, a total of 205 clinical isolates of S. aureus were collected from three university hospitals affiliated with the Kerman University of Medical Science, Kerman, Iran. Screening of methicillin and vancomycin resistance was carried out by phenotypic methods. The resistance and virulence genes of vancomycin-resistant isolates were detected by polymerase chain reaction (PCR). Staphylococcal cassette chromosome mec (SCCmec) and spa typing were used for molecular typing of vancomycin-resistant isolates. Two S. aureus isolates were considered vancomycin-resistant by phenotypic and genotypic methods. Both isolates showed a minimum inhibitory concentration (MIC) ≥ 64 µg/ml and belonged to SCCmec III and spa type t030. Finding vancomycin-resistant S. aureus (VRSA) isolates represents a serious problem. More stringent infection control policies are recommended to prevent transmission of such life-threatening isolates in the hospital setting.
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Antibacterianos/uso terapêutico , Unidades de Terapia Intensiva , Infecções Estafilocócicas , Resistência a Vancomicina , Vancomicina/uso terapêutico , Humanos , Irã (Geográfico) , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus , Vancomicina/farmacologiaRESUMO
In spite of widespread emergence of aminoglycoside resistance, these drugs are still used in the treatment of staphylococcal infections. This study aimed to investigate the distribution of aminoglycoside resistance and genes encoding aminoglycoside - modifying enzymes (AMEs) as well as Staphylococcal Cassette Chromosome mec (SCCmec) type in coagulase negative staphylococci (CoNS) in pediatric patients. Totally, 93 CoNS isolates were examined for susceptibility to aminoglycosides using disk diffusion and/or E-test methods. AMEs genes and SCCmec types were detected using multiplex PCR. Strain typing was performed using repetitive extragenic palindromic (REP) - PCR assay. The non-susceptibility rates to kanamycin, tobramycin, gentamicin, amikacin and netilmicin were 73%, 59%, 49.5%, 16% and 7.5%, respectively. aac(6')-Ie-aph(2â³)-Ia, ant(4')-Ia and aph(3')-IIIa were encountered in 56 (60.2%), 38 (40.8%) and 18 (19.3%) isolates, respectively. In aac(6')-Ie-aph(2â³)-Ia- positive isolates, the non- susceptibility rates to kanamycin, gentamicin, tobramycin, amikacin and netilmicin were 83%, 74%, 73%, 49% and 43%, respectively. SCCmec types included type IV (n = 31), I (n = 17), II (n = 5), III (n = 4), and V (n = 2). Three isolates had two types; I + III (n = 2) and III + IV (n = 1) whereas 11 isolates were non-typeable. AMEs genes carriers were distributed frequently into type IV. We found diverse fingerprint patterns among our isolates. In conclusion, there was a strong correlation between alarming rate of aminoglycoside resistance and methicillin resistance. Discordances between phenotypic and genotypic detection of aminoglycoside resistance were discernible. AMEs genes might be related to SCCmec types.
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Aminoglicosídeos/farmacologia , Coagulase/metabolismo , Infecções Estafilocócicas/microbiologia , Staphylococcus/efeitos dos fármacos , Staphylococcus/enzimologia , Criança , Coagulase/genética , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana/genética , Genes Bacterianos , Gentamicinas/farmacologia , Humanos , Recém-Nascido , Irã (Geográfico) , Testes de Sensibilidade Microbiana , Staphylococcus/genética , Staphylococcus/isolamento & purificaçãoRESUMO
BACKGROUND: Colorectal cancer (CRC) treatment using time-saving and cost-effective targeted therapies with high selectivity and low toxicity drugs, is a great challenge. In primary investigations on Gallocin, as a most proposed factor in CRC pathogenesis caused by Streptococcus gallolyticus, it was surprisingly found that this bacteriocin has four α-helix structures and some anti- cancer sequences. OBJECTIVE: The aim of this study was to determine the ability of Gallocin-based anticancer peptides (ACPs) against epidermal growth factor receptor (EGFR) and vascular epidermal growth factor receptor (VEGFR) and the evaluation of their pharmacokinetics properties using bioinformatics approaches. METHODS: Support vector machine algorithm web-based tools were used for predicting ACPs. The physicochemical characteristics and the potential of anti-cancer activity of Gallocin-derived ACPs were determined by in silico tools. The 3D structure of predicted ACPs was modeled using modeling tools. The interactions between predicted ACPs and targets were investigated by molecular docking exercises. Then, the stability of ligand-receptor interactions was determined by molecular dynamic simulation. Finally, ADMET analysis was carried out to check the pharmacokinetic properties and toxicity of ACP. RESULTS: Four amino acid sequences with anti-cancer potential were selected. Through molecular docking, Pep2, and Pep3 gained the best scores, more binding affinity, and strong attachments by the formation of reasonable H-bonds with both EGFR and VEGFR. Molecular simulation confirmed the stability of Pep3- EGFR. According to pharmacokinetic analysis, the ACPs were safe and truthful. CONCLUSION: Designed peptides can be nominated as drugs for CRC treatment. However, different in-vitro and in-vivo assessments are required to approve this claim.
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Background: Among several causes of infertility, urogenital infections seem to be influencing factors. The effect of bacterial or viral sexually transmitted infections (STIs) on human fertility is not well understood. The aim of this study was to determine the frequency of STIs in cervical samples of infertile and fertile women and study the relationship between these agents and infertility. Methods: In this case-control study, cytobrush was used for collecting of cervical sample from each infertile and fertile woman (n=95) who attended Research and Clinical Centers for Infertility in Kerman, Iran. PCR and real-time PCR methods were used to detect the presence of bacterial (genital Ureaplasma species, genital Mycoplasma species, Chlamydia trachomatis (C. trachomatis), and Gardnerella vaginalis) and viral (herpes simplex virus, human papillomavirus (HPV), and Epstein-Barr virus) agents, respectively. Fisher's exact test and the logistic regression with the significance level of ≤5% were used for statistical analyses. Results: In general, 78.94% and 14.73% of specimens were positive for one or more studied microorganisms, respectively. Among studied agents, only the infection with HPV was significantly different between infertile and fertile groups (p=0.005) which may enhance the likelihood of female infertility (OR=5.30, 95% CI:1.47-19.11, p< 0.05). After adjusting for age, irregular menstrual cycle, abnormal vaginal discharge, and ectopic pregnancy, the odds ratio of infertility in HPV-infected women increased (OR=7.02, 95% CI:1.52-32.3, p<0.05). Conclusion: Since HPV infection is asymptomatic, periodic screening of women in reproductive age especially infertile couples is recommended for early diagnosis and prevention of infection progression and cross contamination.
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Enterococci act as symbionts in human gastrointestinal tract. The present study aimed to evaluate the characteristics of fecal enterococci isolated from infants and adults, and to compare them to the known probiotic bacteria, including lactobacilli species and E. faecalis Symbioflor 1. In total, sporadic distribution of virulence genes was detected among the studied enterococci. Furthermore, the frequency of genes encoding for sex pheromones (ccf and cob), collagen adhesion (ace), cell wall adhesion (efaAfs), and gelatinase (gelE) was observed to be significantly higher in those isolates obtained from infants compared to those obtained from adults. Although the ability of biofilm formation was found in all isolates, the strong biofilm formation was observed in enterococci from infants and strong correlation was observed between the capacities to form biofilm and attachment to Caco-2 cells. Cell-free culture supernatant showed some inhibitory effects on indicator strains, which were related to the production of organic acids (against P. aeruginosa and enteropathogenic E. coli) or both organic acids and proteinaceous antimicrobial agents (against L. monocytogenes and E. faecalis). Approximately, 79% and 71% of the isolates showed strong inhibitory effects on P. aeruginosa and L. monocytogenes, respectively. Unlike lactobacilli, enterococcal cell-free supernatants had no toxicity on intestinal cells. In conclusion, this study shows that some enterococcal isolates obtained from fecal microbiota have characteristics, which are comparable with the known probiotic bacteria. Therefore, these isolates should be considered to find probiotic candidate. The proteinaceous identity of antimicrobial substances derived from these isolates highlighted the probable contribution of bacteriocins into this issue.
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Microbioma Gastrointestinal , Probióticos , Humanos , Enterococcus , Células CACO-2 , Escherichia coli , Fatores de Virulência/genética , Antibacterianos/farmacologia , Enterococcus faecalisRESUMO
BACKGROUND: Wide use of biocidal agents such as benzalkonium chloride (BCC) and chlorhexidine digluconate (CHX) in hospitals and non-hospital environments, has raised concerns over the emergence of non-susceptible strains. Efflux pumps are of known main mechanisms in biocide tolerance which have been rarely addressed in enterococci - members of gut microbiota which can cause serious problems particularly in hospitalized patients. The purpose of this study was to investigate the susceptibility of enterococci from different sources (clinical and fecal isolates) toward BCC and CHX, and its correlation with efflux associated genes. Also, possible link between biocide tolerance and antibiotic resistance was examined. MATERIALS AND METHODS: One hundred and four enterococcus isolates including clinical (n = 54) and fecal isolates (n = 50) were studied for susceptibility toward BCC, CHX, ciprofloxacin, gentamicin and vancomycin. Twelve efflux associated genes were investigated by polymerase chain reaction assay. RESULTS: In clinical isolates, reduced susceptibility to CHX and resistance to gentamicin and ciprofloxacin were significantly higher than fecal isolates. Vancomycin resistance was associated with increasing minimum inhibitory concentration of CHX. Among all investigated genes, only three ones, efrA, efrB and emeA were detected which were significantly associated with reduced susceptibility to CHX and were more frequent among clinical isolates. Also, high level resistance to gentamicin was significantly associated with the presence of efrA/B as well as with reduced susceptibility to CHX. CONCLUSION: As expected, reduced susceptibility to CHX, was significantly higher in clinical isolates. However, the presence of a vancomycin-resistant enterococci among fecal isolates of healthy people which showed resistance/tolerance to studied antimicrobial agents, was unexpected and highlights the need to investigate other non-hospital environments to avoid dissemination of antimicrobial resistance. Correlation between reduced susceptibility to CHX and high level resistance to gentamicin, substantiates monitoring of biocide tolerance particularly in the healthcare settings to control the establishment of antimicrobial resistant strains.
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Background: The role of genital Ureaplasma species, genital Mycoplasma (M) species, and Chlamydia (C.) trachomatis, the most prevalent sexually transmitted bacteria, in male infertility are still not clear. Different reports about the impact of these bacteria on semen quality are controversial. Objective: This study was proposed to determine the frequency of bacteriospermia in men and investigate the relationship between the presence of these bacteria and semen quality using molecular assay. Materials and Methods: In this cross-sectional study, 200 semen samples obtained from men attending the research and clinical centers for fertility in Kerman, Iran, between July and December 2019 were analyzed for semen volume, progressive motility, non-progressive motility, total progressive motility, and viability according to the World Health Organization guidelines. The polymerase chain reaction was used for the detection of related bacteria. Results: The mean values of volume, progressive motility, non-progressive motility, total progressive motility, and viability were significantly lower in infertile men (p < 0.001). Statistically significant correlations were observed between the presence of M. genitalium and progressive sperm motility, M. hominis and semen volume, Ureaplasma parvum and the sperm normal form, and C. trachomatis and the sperm progressive motility and viability. Logistic regression analysis showed that M. genitalium (OR = 8.06, p < 0.001) and C. trachomatis (OR = 16, p = 0.01) were significantly associated with male infertility. Conclusion: During the infertility assessment, clinicians should consider of role C. trachomatis and M. genitalium in male infertility. Screening test particularly for asymptomatic individuals is recommended.
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INTRODUCTION: Enterococcus faecalis is one of the most common pathogens in urinary tract infections (UTIs). Fluoroquinolones have been frequently used to treat E. faecalis UTIs, and the emergence of fluoroquinolone-resistant E. faecalis strains has recently been reported in several countries. This study aimed to elucidate the mechanisms involved in fluoroquinolone resistance in clinical E. faecalis isolates by analyzing mutations in quinolone- resistance-determining regions (QRDRs) of gyrA and parC and investigating the role of some efflux pumps. METHODS: In total, 70 clinical E. faecalis isolates collected from UTIs were identified by phenotypic and genotypic methods. Antimicrobial susceptibility testing was performed and multidrug-resistant (including ciprofloxacin resistant) isolates were studied for minimum inhibitory concentrations to ciprofloxacin, levofloxacin, and ofloxacin. In the following, mutations in QRDRs of gyrA and parC and expression of EfrA, EfrB, and EmeA efflux pumps were investigated in 20 high-level ciprofloxacin resistant and two ciprofloxacin susceptible isolates. RESULTS: High-level resistance to ciprofloxacin was detected in 97.5% of isolates. Sequencing of QRDRs revealed that 65% and 75% of isolates carried mutations in gyrA and parC, respectively. The presence of efflux genes was detected in all studied isolates, but expression of efrA, emeA, and efrB was demonstrated in 50%, 40%, and 30% of resistant isolates, respectively. Neither QRDR mutation nor the expression of efflux genes showed any significant association with MIC. CONCLUSION: Co-incidence of mutation and efflux gene expression in more than half of isolates (13/20) suggests that both mechanisms may play a role in fluoroquinolone resistance. The other unknown mechanisms including different efflux pumps and probably other QRDRs mutations may contribute to fluoroquinolone resistance in E. faecalis.
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Staphylococcus aureus is an important infectious agent in hemodialysis patients. This study was conducted to determine the frequency of S. aureus nasal carriage in hemodialysis patients (HD) and health-care workers (HCW) at the main dialysis center of Bam city, located in southeast of Iran. In this cross-sectional study, a total of 52 nasal swabs were obtained from health-care workers and hemodialysis patients to detect methicillin-sensitive S. aureus (MSSA) isolates. The resistance to different antibacterial agents was determined by disk diffusion method. Also, Panton-Valentine Leukocidin (PVL) - encoding gene as well as Staphylococcal protein A (spa) type were determined. The nasal carriage rate of S. aureus was found to be 24.4% and 18.8% in patients on hemodialysis and health-care workers, respectively. Among identified isolates, no methicillin-resistant S. aureus (MRSA) was found. Only two MSSA isolates (16.7%) were resistant to trimethoprim/sulfamethoxazole. One isolate (8.6%) was positive for pvl gene. Moreover, 8 spa types were found. According to BURP analysis, six out of the 12 S. aureus isolates (50%) belonged to the same clone, indicating a prevalence of a major clone among MSSA in carriage, including patients and HCW. Mupirocin is still the appropriate drug for reducing nasal colonization in our setting. Accumulation of isolates from patients and staff in one spa clonal complex is alarming for the necessity of more serious infection control in this center. Therefore, it is necessary to screen patients and health-care workers as a health priority, in order to prevent cross transmission.
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Meticilina/farmacologia , Diálise Renal , Infecções Estafilocócicas , Staphylococcus aureus/classificação , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Estudos Transversais , Humanos , Irã (Geográfico)/epidemiologia , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Tipagem Molecular , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacosRESUMO
In this study, clinical ampicillin-resistant Enterococcus faecium isolates with minimum inhibitory concentrations (MICs) for ampicillin in the ranges from 128 to Ë512 µg/mL (n = 17) and two ampicillin-susceptible isolates (MIC 1 µg/mL) were investigated. No ß-lactamase production was detected in these isolates. Alterations in the C-terminal part of pbp5 and levels of pbp5 mRNA expression were investigated by sequencing and quantitative real-time qRT-PCR, respectively. Sequencing analysis revealed five different pbp5 alleles (A to E) having differences in 18 amino acid positions spanning from residue 426 to 642. Allele A (V-462 â A, H-470 â Q, M-485 â A, N-496 â K, A-499 â T, E-525 â D, N-546 â T, A-558 â T, G-582 â S, E-629 â V, K-632 â Q, and P-642 â L) was the most frequent allele. The presence of just two susceptible isolates in allele E suggests a possible correlation between amino acid patterns and MIC, even if there is no discernible correlation with specific single amino acid differences. Also, these were the only isolates that showed much lower expression of class B penicillin-binding protein 5 (PBP5) compared to isolates with MIC of 128 or greater. Thus, ampicillin MICs were correlated with PBP5 expression.
Assuntos
Resistência a Ampicilina/genética , Proteínas de Bactérias/genética , Enterococcus faecium/genética , Expressão Gênica/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Proteínas de Ligação às Penicilinas/genética , Alelos , Substituição de Aminoácidos/genética , Ampicilina/farmacologia , Resistência a Ampicilina/efeitos dos fármacos , Antibacterianos/farmacologia , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , RNA Mensageiro/genéticaRESUMO
Enzymatic alteration of aminoglycosides by aminoglycoside-modifying enzymes (AMEs) is the major mechanism of resistance to aminoglycosides. The purpose of this study was to determine the frequency of AME genes, staphylococcal chromosomal cassette mec (SCCmec) types, and molecular analysis of the coagulase (coa) gene in Staphylococcus aureus strains isolated from clinical specimens. Totally, 102 S. aureus were tested by disk diffusion and microbroth dilution methods for susceptibility to aminoglycosides. AMEs genes and SCCmec types were determined by multiplex polymerase chain reaction (PCR). For polymorphism analysis, the 3' end region of the coa gene was amplified by PCR and the products were then subjected to restriction digestion with HaeIII enzyme. Of the 102 S. aureus, 42 (41.2%) were methicillin-resistant S. aureus (MRSA). Thirty-five (83%) of MRSA strains were resistant to kanamycin, 32 (76.2%) to tobramycin, 30 (71.4%) to gentamicin, 25 (59.5%) to amikacin, and 10 (23.8%) to netilmicin. The aac(6')-Ie-aph(2â³) was the most frequent gene among MRSA isolates 19 (45.2%), followed by aph(3')-IIIa 8 (19%), ant(4')-Ia 6 (14.3%), and aph(2â³)-Id 2 (4.8%). SCCmec types included type I 10 (23.8%), II 1 (2.4%), III 21 (50%), and IV 7 (16.7%). Three (7.2%) isolates were nontypeable. Digestion of the PCR products of the coa gene yielded 19 distinct restriction fragment length polymorphism patterns. In conclusion, given the alarming rate of resistance to aminoglycosides among MRSA, the monitoring of aminoglycoside resistance and AME genes should be performed to limit the spread of aminoglycoside resistance among MRSA isolates. Several variants of the coa gene were found in the studied isolates, although the majority of the MRSA isolates belonged to a limited number of coagulase types.
Assuntos
Aminoglicosídeos/metabolismo , Proteínas de Bactérias/genética , Coagulase/genética , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus/genética , Antibacterianos/farmacologia , Humanos , Meticilina/farmacologia , Testes de Sensibilidade Microbiana/métodos , Polimorfismo de Fragmento de Restrição/genética , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologiaRESUMO
Frequent isolation of Enterococcus faecalis from root canal treated teeth with apical periodontitis, has proposed the role of this organism in endodontic treatment failures. Different factors have been suggested in the pathogenicity of this organism. In this study, 22 E. faecalis isolates from canals of root-filled teeth were identified, and phenotypic and genotypic characteristics were investigated. No resistance to vancomycin and gentamicin was noted, and most isolates (91%) were susceptible to ampicillin. Biofilm formation was detected in 73% of the isolates and may be considered as the most important virulence factor involved in the pathogenesis of these isolates.