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1.
Carbohydr Polym ; 291: 119634, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35698353

RESUMEN

In this study, the fabrication of LL37-loaded chitosan nanoparticles (CS/LL37-NPs) was based on an ionotropic gelation method between sodium tripolyphosphate (TPP) and chitosan. Synthesized chitosan nanoparticles (CS-NPs) were approved by Fourier Transform Infrared (FTIR), UV-vis spectroscopy, Dynamic Light Scattering (DLS), Scanning Electron Microscope (SEM), and Transmission Electron Microscopy (TEM). The encapsulation efficiency of LL37 in this delivery system (CS/LL37-NPs) was 86.9%. According to in vitro release profile, the release of LL37 from CS/LL37-NPs was almost complete after 5 days. Additionally, CS/LL37-NPs can cause an increase in the half-life and prolonged LL37 antibacterial activity against Methicillin-resistant Staphylococcus aureus (MRSA). This delivery system demonstrated 68% biofilm formation inhibition compared to the LL37 alone. Also, icaA gene expression in the face of CS/LL37-NPs was significantly decreased. This study showed the important role of delivery systems in enhancing LL37 antibacterial and antibiofilm activity which can be suggested as a promising agent in the inhibition of bacterial growth and the prevention of biofilm formation.


Asunto(s)
Quitosano , Staphylococcus aureus Resistente a Meticilina , Nanopartículas , Antibacterianos/farmacología , Biopelículas , Quitosano/química , Quitosano/farmacología , Nanopartículas/química , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier
2.
Arch Microbiol ; 203(7): 4475-4484, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34137898

RESUMEN

Salmonella enterica is a major food borne pathogen that creates biofilm. Salmonella biofilm formation under different environmental conditions is a public health problem. The present study was aimed to evaluate the combined effects of stressful factors (temperature and pH) on the expression of biofilm, stress, and virulence genes in Salmonella Enteritidis and Salmonella Typhimurium. In this study, the effect of temperature (2, 8, 22.5, 37, 43 °C) and pH (2.4, 3, 4.5, 6, 6.6) on the expression of biofilm production genes (adr A, bap A), virulence genes (hil A, inv A) and the stress gene (RpoS) of S. Enteritidis and S. Typhimurium was evaluated. The response surface methodology (RSM) approach was used to evaluate the combined effect of the above factors. The highest expression of adr A, bap A, hil A, and RpoS gene for S. Typhimurium was at 22 °C-pH 4.5 (6.39-fold increase), 37 °C-pH 6 (3.92-fold increase), 37 °C-pH 6 (183-fold increase), and 37 °C-pH 3 (43.8-fold increase), respectively. The inv A gene of S. Typhimurium was decreased in all conditions. The adr A, bap A, hil A, inv A, and RpoS gene of S. Enteritidis had the highest expression level at 8 °C-pH 3 (4.09-fold increase), 22 °C-pH 6 (2.71-fold increase), 8 °C pH 3 (190-fold increase), 22 °C-pH 4.5 (9.21-fold increase), and 8 °C-pH 3 (16.6-fold), respectively. Response surface methodology (RSM) indicated that the temperature and pH had no significant effect on the expression level of adr A, bap A, hil A, Inv A, and RpoS gene in S. Enteritidis and S. Typhimurium. The expression of biofilm production genes (adr A, bap A), virulence genes (hil A, inv A) and the stress gene (RpoS) of S. Enteritidis and S. Typhimurium is not directly and exclusively associated with temperature and pH conditions.


Asunto(s)
Biopelículas , Salmonella enteritidis , Salmonella typhimurium , Estrés Fisiológico , Temperatura , Virulencia , Concentración de Iones de Hidrógeno , Salmonella enteritidis/genética , Salmonella enteritidis/patogenicidad , Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidad , Estrés Fisiológico/genética , Virulencia/genética
3.
Front Oncol ; 11: 624759, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33738260

RESUMEN

Over the years, conventional cancer treatments, such as chemotherapy with only a limited specificity for tumors, have undergone significant improvement. Moreover, newer therapies such as immunotherapy have undergone a revolution to stimulate the innate as well as adaptive immune responses against the tumor. However, it has been found that tumors can be selectively colonized by certain bacteria, where they can proliferate, and exert direct oncolytic effects as well as stimulating the immune system. Bacterial-mediated cancer therapy (BMCT) is now one example of a hot topic in the antitumor field. Salmonella typhimurium is a Gram-negative species that generally causes self-limiting gastroenteritis in humans. This species has been designed and engineered in order to be used in cancer-targeted therapeutics. S. typhimurium can be used in combination with other treatments such as chemotherapy or radiotherapy for synergistic modification of the tumor microenvironment. Considerable benefits have been shown by using engineered attenuated strains for the diagnosis and treatment of tumors. Some of these treatment approaches have received FDA approval for early-phase clinical trials. This review summarizes the use of Salmonella bacteria for cancer therapy, which could pave the way towards routine clinical application. The benefits of this therapy include an automatic self-targeting ability, and the possibility of genetic manipulation to produce newly engineered attenuated strains. Nevertheless, Salmonella-mediated anticancer therapy has not yet been clinically established, and requires more research before its use in cancer treatment.

4.
Carbohydr Polym ; 251: 117108, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33142645

RESUMEN

Chitosan nanomaterials have become a hot topic in biomedicine due to exerting antimicrobial effects with interestingly high levels of biodegradability and biocompatibility without causing toxicity. Regarded as a potential means of wound dressing with antimicrobial activity, chitosan exhibits higher efficiency when it is functionally modified with other natural compounds, metallic antimicrobial particles and antibiotics. Mechanistically, the antibacterial effect of chitosan is mostly, associated with the death-proceeding leakage of intracellular content, induced by malfunction and altered permeability of the negatively charged cell membrane, on which chitosan is adsorbed. Moreover, chitosan nanoparticles (NPs) are endowed with favorable features of NPs (i.e., large surface-to-volume ratio, high functionalization possibilities and a greater capacity for drug loading), as well as that of their chitosan base, thereby possessing strengthened antibacterial potential. In addition, polycations target negatively charged bacterial membranes, so bacteria cells are more strongly affected by polycationic chitosan NPs than pure chitosan.


Asunto(s)
Antibacterianos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Quitosano/administración & dosificación , Nanopartículas/administración & dosificación , Animales , Antibacterianos/química , Quitosano/química , Humanos , Nanopartículas/química
5.
Microb Drug Resist ; 26(1): 60-70, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31526226

RESUMEN

To characterize the resistance patterns of uropathogenic Escherichia coli (UPEC) in a Tertiary Teaching Hospital in Iran, we conducted a descriptive epidemiology study using molecular techniques. The subjects consisted of patients having acute urinary tract infection, who were enrolled in the study from 2014 to 2017. The antimicrobial susceptibility profile of 101 UPEC isolates was determined by Kirby-Bauer disc diffusion method. Extended spectrum ß-lactamase (ESBL) was detected by the double-disk synergy test. Biofilm formation was done using microtiter plates. The presence of virulence genes (pai, pap, hly, traT, pai, cnf-1, sfa, and afa) was evaluated by a PCR. Molecular typing of UPEC E. coli isolates was performed with fimH and multilocus sequence typing (MLST). 70.3% of isolates were multidrug-resistant. 37.6% of isolates were Extended spectrum ß-lactamases (ESBLs) producer. Strong biofilm formation was seen in 27.7%. Forty-seven different fimH allelic variants were identified. Among identified fimH allelic variants, the most common types were f1 (18.8%) and f14 (18.8%). ST131 (54.5%) was the most prevalent clonal group significantly correlated with the pai gene. Seven sequence types (STs) were detected only once (ST405, ST410, ST450, ST636, ST648, ST1193, and ST6451). Clonal groups showed no significant differences in terms of antibiotic resistance patterns. There was no significant difference between virulence genes and antibiotic resistance patterns in the studied clonal groups. To our knowledge, the present study is the first study in Iran that investigated the genotypic diversity of UPEC isolates by MLST and fimH typing methods. The two methods might serve as a useful molecular test for surveillance and epidemiological studies of isolates.


Asunto(s)
Antibacterianos/farmacología , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones Urinarias/tratamiento farmacológico , Escherichia coli Uropatógena/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Genotipo , Hospitales de Enseñanza , Humanos , Irán/epidemiología , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Tipificación Molecular , Tipificación de Secuencias Multilocus , Centros de Atención Terciaria , Infecciones Urinarias/epidemiología , Infecciones Urinarias/microbiología , Escherichia coli Uropatógena/aislamiento & purificación , Virulencia/genética
6.
Microb Pathog ; 140: 103946, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31874231

RESUMEN

This study aimed to evaluate the effects of Cinnamaldehyde, Carvacrol, and honey either alone or in combinations on the expression of exoS and ampC genes in multidrug-resistant (MDR) P. aeruginosa isolates. Thirty-five P. aeruginosa isolates were recovered from burn wound infections of patients admitted to the burn ward of Besat hospital of Hamadan, Iran, during 2018. Antibiotic susceptibility testing was performed using the Kirby-Bauer disk diffusion method to identify MDR isolates. The antibacterial effects of Cinnamaldehyde, Carvacrol, and honey either alone or in combinations with each other were compared to Imipenem (as the control group) using the broth dilution method. The expressions of exoS and ampC genes were determined in bacteria treated with sub-minimum inhibitory concentration (MIC) of the ternary combination of Cinnamaldehyde, Carvacrol, and honey by Real-Time-PCR. The data were analyzed using SPSS software applying student t-test, Kruskal-Wallis, and Mann-Whitney U tests. The P-value less than 0.05 was considered as statistically significant. The average MICs of Cinnamaldehyde, Carvacrol, and honey were 0.82-0.01, 0.01-0.6, and 62.5-250 µg/mL, respectively. The average MIC of the mentioned compounds was 430 times lower than that of Imipenem. A synergistic effect was detected between these drugs against 70% of the isolates. At sub-MIC concentration, the triple combination of Cinnamaldehyde, Carvacrol, and honey reduced the expressions of exoS and ampC genes by 6.12 and 2.85 folds, respectively. The combination of Cinnamaldehyde, Carvacrol, and honey showed a higher antibacterial effect than Imipenem. However, it needs confirmation with more isolates.


Asunto(s)
Acroleína/análogos & derivados , Antibacterianos/farmacología , Cimenos/farmacología , Farmacorresistencia Bacteriana Múltiple , Miel/análisis , Pseudomonas aeruginosa/efectos de los fármacos , ADP Ribosa Transferasas/genética , ADP Ribosa Transferasas/metabolismo , Acroleína/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Quemaduras/microbiología , Sinergismo Farmacológico , Femenino , Humanos , Imipenem/farmacología , Irán , Masculino , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Infección de Heridas/microbiología , beta-Lactamasas/genética , beta-Lactamasas/metabolismo
7.
Artículo en Inglés | MEDLINE | ID: mdl-30976386

RESUMEN

Background: The aim of this study was to characterize class 1,2 and 3 integrons in clinical MDR Klebsiella pneumoniae isolates in Kashan, Iran. Methods: One hundred-eighty one Klebsiella pneumoniae were recovered from clinical specimens during November 2013 to October 2014. Antimicrobial susceptibility patterns were determined by disk diffusion method according to the Clinical and Laboratory Standards Institute (CLSI) guidelines for detection of MDR strains. Of the 181 Klebsiella pneumoniae, 146 (80.7%) of isolates were isolated from nosocomial infected patients and 150 (82.9%) identified as MDR isolates. The PCR amplification was used to show presence of class 1, 2 and 3 integrons among MDR strains. The PCR method and sequencing were used for evaluation of cassette content of integrons. Results: Of the MDR K. pneumoniae isolates, 150 (100%) and 55 (36.7%) carried intI1 and intI2 genes, respectively. None of the MDR Klebsiella pneumoniae isolates carried class 3 integrons. Amplification of conserved segment (CS) of class 1 and class 2 integrons revealed 10 different arrays including: No. cassette; dfrA5, dfrA30; aadA2; aadA2, dfrA12; dfrA17, aadA5, aadA4; dfrA5, dfrA30, aadA2; dfrA5, dfrA30, aadA2, dfrA12, dfrA5, dfrA30, dfrA17, aadA5, aadA4; aadA2, aadA2, dfrA12; dfrA5, dfrA30, aadA2, aadA2, dfrA12 and 4 arrays including: No. cassette; aadA1; dfrA1-sat1; aadA1, dfrA1-sat1, respectively. Conclusions: The finding of present study revealed a high prevalence of integrons especially class 1 among MDR K. pneumoniae isolates from nosocomial infections in Kashan, which led to rapid extension of MDR strains.


Asunto(s)
Antibacterianos/farmacología , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana Múltiple , Integrones , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , ADN Bacteriano/genética , Pruebas Antimicrobianas de Difusión por Disco , Evolución Molecular , Humanos , Lactante , Irán , Klebsiella pneumoniae/efectos de los fármacos , Persona de Mediana Edad , Adulto Joven
8.
Probiotics Antimicrob Proteins ; 11(4): 1227-1235, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-30535534

RESUMEN

This study was carried out to evaluate the effects of probiotic supplementation on genetic and metabolic profiles in patients with gestational diabetes mellitus (GDM) who were not on oral hypoglycemic agents. This randomized, double-blind, placebo-controlled clinical trial was conducted in 48 patients with GDM. Participants were randomly divided into two groups to intake either probiotic capsule containing Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium bifidum, Lactobacillus fermentum (2 × 109 CFU/g each) (n = 24) or placebo (n = 24) for 6 weeks. Probiotic intake upregulated peroxisome proliferator-activated receptor gamma (P = 0.01), transforming growth factor beta (P = 0.002) and vascular endothelial growth factor (P = 0.006), and downregulated gene expression of tumor necrosis factor alpha (P = 0.03) in peripheral blood mononuclear cells of subjects with GDM. In addition, probiotic supplementation significantly decreased fasting plasma glucose (ß, - 3.43 mg/dL; 95% CI, - 6.48, - 0.38; P = 0.02), serum insulin levels (ß, - 2.29 µIU/mL; 95% CI, - 3.60, - 0.99; P = 0.001), and insulin resistance (ß, - 0.67; 95% CI, - 1.05, - 0.29; P = 0.001) and significantly increased insulin sensitivity (ß, 0.009; 95% CI, 0.004, 0.01; P = 0.001) compared with the placebo. Additionally, consuming probiotic significantly decreased triglycerides (P = 0.02), VLDL-cholesterol (P = 0.02), and total-/HDL-cholesterol ratio (P = 0.006) and significantly increased HDL-cholesterol levels (P = 0.03) compared with the placebo. Finally, probiotic administration led to a significant reduction in plasma malondialdehyde (P < 0.001), and a significant elevation in plasma nitric oxide (P = 0.01) and total antioxidant capacity (P = 0.01) was observed compared with the placebo. Overall, probiotic supplementation for 6 weeks to patients with GDM had beneficial effects on gene expression related to insulin and inflammation, glycemic control, few lipid profiles, inflammatory markers, and oxidative stress.


Asunto(s)
Diabetes Gestacional/tratamiento farmacológico , Probióticos/administración & dosificación , Adulto , Bifidobacterium bifidum/fisiología , Glucemia/metabolismo , Diabetes Gestacional/genética , Diabetes Gestacional/metabolismo , Método Doble Ciego , Femenino , Humanos , Insulina/sangre , Lactobacillus acidophilus/fisiología , Lacticaseibacillus casei/fisiología , Lípidos/sangre , Malondialdehído/metabolismo , PPAR gamma/genética , PPAR gamma/metabolismo , Embarazo , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Triglicéridos/sangre , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adulto Joven
9.
Mol Immunol ; 96: 88-97, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29525454

RESUMEN

Proteus mirabilis is a common pathogen in urinary tract infections (UTIs). There is no vaccine against P. mirabilis, thus a novel multi-peptide vaccine of MrpA, UcaA and Pta factors of P. mirabilis we designed and a mice model was used to evaluate its efficacy in combination with AddaVax adjuvant. According to the bioinformatics studies, 7 fragments of MrpA (31-75, 112-146), UcaA (68-117, 132-156) and Pta (210-265, 340-400, 496-570) with B and T cell epitope regions were selected for fusion construction. Mice subcutaneously vaccinated with the fusion MrpA.Pta.UcaA induced a significant increase in serum and mucosal IgG and IgA responses. The fusion also showed a significant induction in cellular responses (Th1 and Th2). The addition of AddaVax to fusion and the mixture of MrpA, UcaA, and Pta (MUP) improved the humoral and cellular responses, especially the IgG2a and IFN-γ (Th1 responses) levels. Fusion with and without AddaVax and MUP + AddaVax could maintain significant humoral responses until 6 months after the first vaccine dose. All vaccine combinations with and without adjuvant showed high effectiveness in the protection of the bladder and kidney against experimental UTI; this could be attributed to the significant humoral and cellular responses. The present study suggests that the AddaVax-based vaccine formulations especially the fusion Pta.MrpA.UcaA admixed with AddaVax as potential vaccine candidates for protection against P. mirabilis. Furthermore, AddaVax could be considered as an effective adjuvant in designing other vaccines against UTI pathogens.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Vacunas Bacterianas/inmunología , Infecciones por Proteus/prevención & control , Escualeno/inmunología , Infecciones Urinarias/prevención & control , Animales , Vacunas Bacterianas/farmacología , Modelos Animales de Enfermedad , Ratones , Polisorbatos/farmacología , Proteus mirabilis , Escualeno/farmacología , Infecciones Urinarias/microbiología , Vacunas de Subunidad
10.
Microb Pathog ; 115: 25-30, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29248513

RESUMEN

Klebsiella pneumoniae is an important human pathogen that is considered in recent years due to nosocomial infections resistant to treatment as well as the ability to form biofilms particularly in patients with urinary tract infection in ICU or hospital. The aim of this study was to evaluate the prevalence of VIM1, IMP1 genes and their ability to form biofilm in K. pneumoniae strains isolated from patients with urinary tract infection. In the study, using culture and biochemical methods, 1807 K. pneumoniae samples were isolated from patients with urinary tract infection hospitalized or referred to hospitals in Qom in 2013-2014. For isolation of MBL producing isolates, Double Disk Synergy Test (DDST) was used. Then MBL positive isolates were examined for the presence of VIM1, IMP1 genes using PCR method. Furthermore, all strains were investigated for biofilm formation by phenotypic microplate method. From 3165 urine samples cultured, 1807 isolates of K. pneumoniae were isolated and 109 strains (93.2%) were positive for MBL enzymes production. PCR results showed that the prevalence of VIM1 and IMP1 genes are 15.6 and 6.4%, respectively. The Phenotypic method indicated that 91.2% of isolates formed biofilm. Biofilm formation in K. pneumoniae isolates is high and there is a significant relationship between strong biofilm formation and prevalence of VIM1 and IMP1 genes. Also due to the presence of MBL genes in K. pneumoniae and horizontal transfer of genes to other bacteria, and to control the indiscriminate use of antibiotics, the hospital infection control methods must be considered.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Genes Bacterianos/genética , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/fisiología , beta-Lactamasas/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Niño , Preescolar , Estudios Transversales , Pruebas Antimicrobianas de Difusión por Disco , Farmacorresistencia Bacteriana Múltiple/genética , Femenino , Transferencia de Gen Horizontal , Hospitales , Humanos , Lactante , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/aislamiento & purificación , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Fenotipo , Infecciones Urinarias/microbiología , Orina/microbiología , Adulto Joven
11.
Iran J Microbiol ; 9(5): 283-287, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29296273

RESUMEN

BACKGROUND AND OBJECTIVES: New Delhi metallo-ß-lactamase (NDM) is a newly emerging metallo-ß-lactamases, which can destroy all ß-lactams including carbapenems. Therefore, this study aimed at evaluating New Delhi metallo-ß-lactamase-1-production in clinical isolates of Klebsiella pneumoniae in Kashan, Iran. MATERIALS AND METHODS: In a cross-sectional study, 181 K. pneumoniae isolates were collected from clinical samples of patients, who referred to Shahid Beheshi hospital in Kashan during November 2013 and October 2014. Antimicrobial susceptibility patterns were determined using disk diffusion method, according to CLSI guidelines. Metallo-ß-lactamase (MBL) production was identified among imipenem-resistant K. pneumoniae isolates using imipenem-EDTA double disk synergy test (EDTA-IMP DDST). PCR method and sequencing were used to detect integron Class 1 and blaNDM-1 gene. Statistical analyses were performed using SPSS software Version 16. RESULTS: Of the 181 K. pneumoniae isolates, 36 (19.9 %) were imipenem-resistant strains. A total of 28 out of 36 (77.7%) imipenem-resistant K. pneumoniae isolates were identified as MBL producer strains. Also, 150 (82.9%) K. pneumoniae isolates carried intI1 gene, and 20 (11.1%) K. pneumoniae isolates harbored blaNDM-1 gene. CONCLUSION: Our study revealed a high frequency of MBL production and the presence of blaNDM-1 among K. pneumoniae strains, especially among hospitalized patients, which is alarming. Moreover, the presence of Class 1 integrons in all multi-drug resistant K. pneumoniae isolates highlights the risk of rapid spread of the resistance genes, especially in clinical settings.

12.
Biologicals ; 45: 20-26, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27836582

RESUMEN

Burn wound infections caused by multidrug-resistant Pseudomonas aeruginosa strains are a serious challenge to therapy because of the complex pathogenesis and paucity of new effective antibiotics. Therefore, there is renewed interest in developing antibody-based therapeutic strategies. Immunotherapy strategies typically target selected virulence factors that are expressed by the majority of clinical strains of P. aeruginosa, particularly because virulence factors mediate infection. Here we used a murine model of burn wound infection to evaluate the efficacy of antibodies raised against the divalent type b flagellin and PilA (flagellin b + PilA), as acute virulence factors, to prevent and treat infection. Antibodies to flagellin b + PilA exhibited superior synergistic effects that improved opsono-phagocytosis and cell invasion compared with antibodies to each monovalent flagellin b or PilA. Further, when used for prophylaxis, the antibodies against flagellin b + PilA and combined therapeutic and prophylactic regimens markedly improved the survival of mice infected with disparate P. aeruginosa strains from 91.6% to 100% compared with treatment using imipenem. Therefore, antibodies against flagellin b + PilA interfere with the activities of their respective cognate individual target antigens and enhance coverage against clinical strains of P. aeruginosa that may not express one of these two virulence factors.


Asunto(s)
Anticuerpos Antibacterianos/farmacología , Quemaduras , Proteínas Fimbrias/inmunología , Flagelina/inmunología , Inmunoterapia , Infecciones por Pseudomonas , Pseudomonas aeruginosa/inmunología , Infección de Heridas , Animales , Anticuerpos Antibacterianos/inmunología , Quemaduras/inmunología , Quemaduras/microbiología , Quemaduras/terapia , Masculino , Ratones , Ratones Endogámicos BALB C , Infecciones por Pseudomonas/inmunología , Infecciones por Pseudomonas/terapia , Conejos , Infección de Heridas/inmunología , Infección de Heridas/microbiología , Infección de Heridas/terapia
13.
Autoimmune Dis ; 2016: 7529078, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27800178

RESUMEN

Pemphigus vulgaris are autoimmune blistering diseases that may result in significant morbidity and death. Immunosuppressive therapy of pemphigus vulgaris would predispose the patients to infections. The aim of this study was to assess the prevalence of S. aureus infection and PVL gene in patients with pemphigus admitted to dermatology clinic. Materials and Methods. This descriptive study was conducted on 196 pemphigus vulgaris patients (119 males, 77 females) admitted to dermatology clinic between 2014 and 2015. In this study, the diagnosis of pemphigus vulgaris was made by histology, immunofluorescence pattern of perilesional skin, and indirect immunofluorescence testing of serum. Data were collected through a questionnaire. Results. 59.1% of pemphigus vulgaris patients had S. aureus infection. 49 out of 116 were methicillin-resistant. PVL gene was detected in 25 out of 116 S. aureus positive patients. Conclusion. This is the first report of S. aureus infection in pemphigus patients in Iran. More than forty percent of isolates were methicillin-resistant S. aureus. PVL gene carried by methicillin-resistant S. aureus was high in this study.

14.
Arch Trauma Res ; 5(3): e33664, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27800466

RESUMEN

BACKGROUND: Metallo-ß-lactamase (MBL)-producing Pseudomonas aeruginosa is a significant pathogen in burn patients. OBJECTIVES: The aim of this study was to determine the prevalence of carbapenem-resistant P. aeruginosa isolates, including those resistant to imipenemase (IMP), in a burn unit in Isfahan, Iran. PATIENTS AND METHODS: One hundred and fifty P. aeruginosa isolates from burn patients were tested for antibiotic susceptibility by the disc diffusion method in accordance with CLSI guidelines. Production of MBL was identified with the EDTA disk method. DNA was purified from the MBL-positive isolates, and detection of the blaIMP gene was performed with PCR. RESULTS: Fifty-seven out of 150 (38%) isolates were multi-drug resistant (MDR), and 93 (62%) were extensively-drug resistant (XDR). Among all isolates, the resistance rate to ciprofloxacin, tobramycin, imipenem, meropenem, amikacin, ceftazidime, and cefepime was higher than 90%, while the resistance rates to piperacillin/tazobactam and aztreonam were 70.7% and 86%, respectively. Colistin and polymyxin B remained the most effective studied antibiotics. All of the imipenem-resistant P. aeruginosa isolates were MBL-positive, and 107 out of 144 (74.3%) of the MBL isolates were positive for the blaIMP gene. CONCLUSIONS: The results of this study show that the rate of P. aeruginosa-caused burn wound infections was very high, and many of the isolates were resistant to three or more classes of antimicrobials. Such extensive resistance to antimicrobial classes is important because few treatment options remain for patients with burn wound infections. blaIMP -producing P. aeruginosa isolates are a rising threat in burn-care units, and should be controlled by conducting infection-control assessments.

15.
Jundishapur J Microbiol ; 8(10): e22345, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26587205

RESUMEN

BACKGROUND: Pseudomonas aeruginosa possesses a variety of virulence factors and infections caused by multidrug-resistant P. aeruginosa (MDRPA) in burn patients are a public health problem. OBJECTIVES: The aim of this study was to determine the antibiotic resistance pattern, the biofilm formation, the prevalence of MDRPA and two virulence genes (nan1 and exoA) among P. aeruginosa isolated from burn patients. PATIENTS AND METHODS: A total of 144 isolates of P. aeruginosa were collected from burn patient at the Burn Centre of Tehran, Iran, between March 2013 and July 2013. Antibiotic susceptibility test was performed via agar disk diffusion method. The ability of producing biofilm was examined by crystal violet microtiter plate assay and the prevalence of the exoA and nan1 genes among the isolates was determined by polymerase chain reaction (PCR). RESULTS: A high rate of resistance was seen against ciprofloxacin (93.7%), aztreonam (86.8%), piperacillin (85.4%), ceftazidime (82.6%), amikacin (82%) and imipenem (79.2%). In total, 93.1% of the isolates were characterized as MDRPA. Biofilm formation was seen in 92.4% of the isolates. The prevalence of the exoA and nan1 genes were 75% and 11.8% among the isolates, respectively. CONCLUSIONS: The high rate of MDRPA and its ability to produce biofilm is an alarm for public health. The statistical analysis showed that biofilm production in the MDRPA isolates was significantly higher than that in the non-MDRPA isolates (P < 0.001).

16.
Jundishapur J Microbiol ; 8(6): e18591, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26301061

RESUMEN

BACKGROUND: Coagulase-negative staphylococci (CoNS) are opportunistic pathogens. Methicillin resistance is common in CoNS and may play an important role as reservoir of staphylococcal cassette chromosome mec (SCCmec) for Staphylococcus aureus. OBJECTIVES: The aim of this study was to determine molecular characteristics of nasal carriage of methicillin-resistant coagulase negative staphylococci among students. MATERIALS AND METHODS: MR-CoNS from both nares of students were collected. Resistance to methicillin was determined by cefoxitin (30µg) disk diffusion test. SCCmec typing was performed using multiplex PCR by mec complex classes and ccr genes. Antimicrobial susceptibility profiles were determined on Mueller-Hinton agar according to CLSI. RESULTS: A total of 600 consecutive students were enrolled in this study; 430 of whom (71.7%) had CoNS. Seventy-two MR-CoNS strains, 21 (29.2%) S. lugdunensis, 17 (23.6%) S. haemolyticus, 17 (23.6%) S. saprophyticus, 9 (12.5%) S. epidermidis and 8 (11.1%) S. schleiferi were isolated. MR-CoNS rate in nasal carriage was 16.7%. All strains were susceptible to vancomycin. Forty-eight (66.7%) had a single SCCmec type including types I (n = 5), II (n = 4), III (n = 7), IV (n = 19) and V (n = 13), whereas 5 (6.9%) had two types including III + IV (n = 2), III + V (n = 1) and IV + V (n = 2). Nineteen strains (26.4%) were non-typeable for their SCCmec and ccr. Types IV and V SCCmec were associated with S. lugdunensis and S. haemolyticus, respectively. CONCLUSIONS: SCCmec types IV and V were prevalent in MR-CoNS and few isolates could harbor more than one type.

17.
Jundishapur J Microbiol ; 8(4): e15576, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26034530

RESUMEN

BACKGROUND: Chlamydia trachomatis is one of the major bacterial agents of the sexually transmitted diseases worldwide, especially among young females. There is no data regarding the prevalence of genital Chlamydia infection among young females in Kashan, Iran. OBJECTIVES: The current study aimed to determine the prevalence of endocervical C. trachomatis infection among females aged 17 - 35 years in Kashan, Iran. PATIENTS AND METHODS: In the current descriptive study, 255 endocervical swab samples were collected from the obstetrics and gynecology clinics of Kashan, Iran from December 2012 to July 2013. Cervical swabs were placed in transport media and sent to the laboratory. To identify C. trachomatis in the samples Polymerase Chain Reaction (PCR) was performed to amplify a sequence in the cryptic plasmid, generating a fragment of about 512base pair. Demographic data was collected considering the relevant risk factors by a standard questionnaire. RESULTS: A total of 255 females were tested. The prevalence of genital C. trachomatis was 2.4% (95% confidence interval [CI] 0.54% - 4.26%); 3.2% of the females in the ≤ 25-year-old group were positive versus 1.8% in the 26 - 35-year-old group. The most general presented symptoms of genital C. trachomatis infection were vaginal discharge (66.6%) and lumbar pain (50%). No significant relationships were found between C. trachomatis infection and the risk factors. CONCLUSIONS: To the authors' knowledge this is the first study to describe endocervical C. trachomatis infection in this area. The obtained results also emphasized the importance of routine diagnosis of C. trachomatis to control of the infection.

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