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1.
Rev. cir. (Impr.) ; 72(3): 217-223, jun. 2020. tab
Article in Spanish | LILACS | ID: biblio-1115545

ABSTRACT

Resumen Introducción: Es importante mantener programas de vigilancia bacteriana para disminuir resistencia y definir esquemas farmacológicos adecuados. Los pacientes con abdomen agudo representan un grupo microbiológico especial. Objetivos: Hacer una revisión de agentes patógenos en pacientes adultos operados en nuestro Servicio de Urgencia por patología abdominal con líquido libre y analizar los resultados obtenidos de cultivos respecto a las cepas y la susceptibilidad a los antibióticos. Materiales y Método: Estudio de cohorte prospectiva con estadística descriptiva. Se incluyen pacientes consecutivos, mayores de 18 años, operados por abdomen agudo que presentan líquido libre intraperitoneal entre noviembre de 2017 y abril de 2018. Se excluyen casos con terapia antimicrobiana, hospitalización y/o cirugía en los 3 meses previos. Se registran los cultivos positivos, cepas aisladas, susceptibilidad antimicrobiana, datos demográficos y evolución clínica. Resultados: De 63 pacientes 55% fueron hombres, edad promedio 52,2 años. Las patologías más frecuentes fueron de origen apendicular (62%) y de causa entérica (30%). En un 44% el cultivo fue positivo y en 36% con más de un germen. Escherichia coli fue el patógeno más frecuente (64,2%) seguidos de Enterococcus faecium y Streptococcus anginosus (7,1%). De los otros patógenos cultivados sólo se observó resistencia múltiple en un caso aislado de Morganella Morganii. Conclusiones: Estos datos constituyen la realidad microbiológica local en abdomen agudo. La Escherichia Coli sigue siendo el germen más frecuente, debe enfrentarse con profilaxis y tratamiento antibiótico adecuado. Es necesario mantener vigilancia microbiología local para un manejo acorde.


Introduction: It is important to maintain bacterial surveillance programs to decrease resistance and define adequate pharmacological schemes. Patients with abdomen represent a special microbiological group. Objetives: Make a review of pathogens in adult patients operated in our Emergency Service for abdominal pathology with free fluid and analyze the results obtained from cultures with respect to the strains and susceptibility to antibiotics. Materials and Method: Prospective cohort study with descriptive statistics. We include consecutive patients, older than 18 years old, operated on by abdomen who present free intraperitoneal fluid between November 2017 and April 2018. Cases with antimicrobial therapy, hospitalization and/or surgery 3 months prior are excluded. Positive cultures, isolated strains, antimicrobial susceptibility, demographic data and clinical evolution are recorded. Results: Of 63 patients, 55% were men and the average age was 52.2 years. The most frequent pathologies were of appendicular origin (62%) and of enteric origin (30%). In 44% the crop was positive and in 36% with more than one germ. Escherichia coli was the most frequent pathogen (64.2%) followed by Enterococcus faecium and Streptococcus anginosus (7.1%). Of the others, cultivated pathogens have only observed multiple resistance in an isolated case of Morganella Morganii. Conclusions: These data include the local microbiological reality in acute abdomen. Escherichia coli is still the most frequent germ that must be faced with the profile and the appropriate treatment. It is necessary to maintain local microbiology surveillance for a proper management.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Bacterial Infections/drug therapy , Abdomen, Acute/surgery , Abdomen, Acute/complications , Anti-Bacterial Agents/therapeutic use , Bacterial Infections/etiology , Bacterial Infections/prevention & control , Ascitic Fluid , Ciprofloxacin/therapeutic use , Enterococcus faecium/drug effects , Streptococcus anginosus , Escherichia coli/drug effects , Abdomen, Acute/pathology , Metronidazole
2.
Rev. chil. nutr ; 47(2): 281-285, abr. 2020. tab
Article in English | LILACS | ID: biblio-1115499

ABSTRACT

Synthetic preservatives are widely present in processed foods, but most of them have carcinogenic potential, requiring the development of new natural alternatives such as fruit extracts, for microbial control. The objective of the study was to evaluate the chemical characterization, antioxidant, and antimicrobial activity of the sugar apple pulp (Annona squamosa L.). Physicochemical characteristics were evaluated, an extract was prepared, and its antioxidant activity by DPPH method and antimicrobial by disk diffusion. Minimal inhibitory concentration and minimum bactericidal concentration against strains of Salmonella typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus were evaluated. The physicochemical analysis revealed that sugar apple pulp had 75.0% moisture, 3.0% ash, 4.0% protein, 0.2% lipids, 3.3% fibers, and 14.5% carbohydrates. The antioxidant activity of the extract by the DPPH method was 20.6%. The pulp extract from the sugar apple had inhibition zone for Staphylococcus aureus, satisfactory inhibitory effect against Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, and Salmonella Typhimurium, but did not present a bactericidal effect. Sugar apple pulp presents adequate levels of nutrients and potential for food application due to its microbiological activity and antioxidant properties.


Los conservantes sintéticos están ampliamente presentes en los alimentos procesados, pero la mayoría tienen potencial carcinogénico, lo que requiere el desarrollo de nuevas alternativas naturales para el control microbiano, como los extractos de frutas. El objetivo del estudio fue evaluar la caracterización química, la actividad antioxidante y antimicrobiana de la pulpa de manzana de azúcar (Annona squamosa L.). Se evaluaron las características fisicoquímicas, y se evaluó su actividad antioxidante mediante el método DPPH y antimicrobiano por difusión en disco, concentración inhibitoria mínima y concentración bactericida mínima contra cepas de Salmonella Typhimurium, Escherichia coli, Listeria monocytogenes y Staphylococcus aureus. El análisis fisicoquímico reveló que la pulpa de manzana de azúcar tiene 75.0% de humedad, 3.0% de cenizas, 4.0% de proteínas, 0.2% de lípidos, 3.3% de fibras y 14.5% de carbohidratos. La actividad antioxidante del extracto por el método DPPH fue del 20.6%. El extracto de pulpa de la manzana de azúcar tenía zona de inhibición para Staphylococcus aureus, efecto inhibidor satisfactorio contra Staphylococcus aureus, Escherichia coli, Listeria monocytogenes y Salmonella Typhimurium, pero no presenta efecto bactericida. La pulpa de manzana de azúcar presenta niveles adecuados de nutrientes y potencial para la aplicación de alimentos debido a su actividad microbiológica y propiedades antioxidantes.


Subject(s)
Plant Extracts/pharmacology , Annona/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Salmonella typhimurium/drug effects , Staphylococcus aureus/drug effects , Carbohydrates/analysis , Plant Extracts/chemistry , Proteins/analysis , Microbial Sensitivity Tests , Escherichia coli/drug effects , Lipids/analysis , Listeria monocytogenes/drug effects , Anti-Bacterial Agents/chemistry , Antioxidants/chemistry
3.
Braz. arch. biol. technol ; 63: e20180568, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132273

ABSTRACT

Abstract Sophorolipids are glycolipids that have natural antimicrobial properties and present great potential in the pharmaceutical field. The present study aimed to produce sophorolipids from Candida bombicola using a chicken fat-based medium and evaluate the antimicrobial activity against Gram-negative (Proteus mirabilis, Escherichia coli, Salmonella enterica subsp. enterica) and Gram-positive bacteria (Enterococcus faecium, Staphylococcus aureus and Streptococcus mutans). The production of sophorolipids reached 27.86 g L-1. Based on the structural characterization, 73.55% of the sophorolipids present a mixture of acidic monoacetylated C18:2 and lactonic diacetylated C16:0, and 26.45% were present in the diacetylated C18:1 lactonic form. Bacteria submitted to sophorolipid exposure showed a reduction in viability at doses of 500 μg mL-1 and 2,000 μg mL-1 against Gram-positive and Gram-negative bacteria, respectively. These results suggest that sophorolipids produced in chicken fat medium may be used as antimicrobial agents to prevent or eliminate contamination by different pathogens.


Subject(s)
Candida/metabolism , Glycolipids/pharmacology , Enterococcus faecium/drug effects , Gram-Negative Bacteria/drug effects , Anti-Bacterial Agents/pharmacology , Proteus mirabilis/drug effects , Glycolipids/isolation & purification , Salmonella enterica/drug effects , Escherichia coli/drug effects , Anti-Bacterial Agents/isolation & purification
4.
Biol. Res ; 53: 26, 2020. graf
Article in English | LILACS | ID: biblio-1124211

ABSTRACT

BACKGROUND: There Is an emerging field to put Into practice new strategies for developing molecules with antimicrobial properties. In this line, several metals and metalloids are currently being used for these purposes, although their cellular effect(s) or target(s) in a particular organism are still unknown. Here we aimed to investigate and analyze Au3+ toxicity through a combination of biochemical and molecular approaches. RESULTS: We found that Au3+ triggers a major oxidative unbalance in Escherichia coli, characterized by decreased intracellular thiol levels, increased superoxide concentration, as well as by an augmented production of the antioxidant enzymes superoxide dismutase and catalase. Because ROS production is, in some cases, associated with metal reduction and the concomitant generation of gold-containing nanostructures (AuNS), this possibility was evaluated in vivo and in vitro. CONCLUSIONS: Au3+ is toxic for E. coli because it triggers an unbalance of the bacterium's oxidative status. This was demonstrated by using oxidative stress dyes and antioxidant chemicals as well as gene reporters, RSH concentrations and AuNS generation.


Subject(s)
Oxidation-Reduction/drug effects , Oxidative Stress/drug effects , Escherichia coli/drug effects , Metal Nanoparticles/toxicity , Gold/toxicity
5.
Rev. Soc. Bras. Med. Trop ; 53: e20190429, 2020. tab, graf
Article in English | LILACS | ID: biblio-1057306

ABSTRACT

Abstract INTRODUCTION: Nosocomial and community acquired urinary tract infections (UTIs) are one of the most encountered infections in the world. METHODS: This study aimed to determine the antibiotic susceptibility, phylogeny, and virulence genes of 153 Escherichia coli strains isolated from UTIs. Antimicrobial susceptibility of the isolates to different classes of antimicrobials was determined by the VITEK-2 automated system. Presence of virulence genes and phylogenetic groups were investigated by PCR. RESULTS: Regarding susceptibility to antimicrobials, ampicillin resistance was most abundant (67.3%), followed by amoxicillin-clavulanic acid (50.9%); least abundant was resistance to amikacin (1.3%) and nitrofurantoin (1.3%). Multi drug resistance (MDR) was observed in 34.6% of the isolates, and all isolates were found to be susceptible to imipenem, meropenem and fosfomycine. The majority of the isolates belonged to the phylogenetic group B23 (35.9%), followed by A1 (20.9%), D1 (18.9%), D2 (12.4%), A0 (%5.9), B1 (3.9%) and B2 (1.9%). Among E. coli strains examined, 49% had iucD, 32.7% papE-F, 26.1% papC, 15% cnf2, 11.1% sfa, 7.8% cnf1, 1.3% afaE, 1.3% afaD, 1.3% hlyA, 0.7% f17a-A, 0.7% clpG and 0.7% eaeA genes. CONCLUSIONS Our research demonstrated that virulence factors were distributed among different phylogroup/subgroups, which play a role in UTIs pathogenesis in humans. For this reason, complex and detailed studies are required to determine the relationship between virulence factors and specific E. coli strains that cause UTIs in humans.


Subject(s)
Humans , Urinary Tract Infections/microbiology , Virulence Factors/genetics , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli Infections/microbiology , Anti-Bacterial Agents/pharmacology , Phylogeny , RNA, Ribosomal, 16S , Microbial Sensitivity Tests , Polymerase Chain Reaction , Escherichia coli/isolation & purification , Genotype
6.
Rev. Inst. Nac. Hig ; 50(1-2): 4-13, Diciembre 2019. Tab
Article in Spanish | LILACS, LIVECS | ID: biblio-1118292

ABSTRACT

Las infecciones del tracto urinario afectan al ser humano a lo largo de su vida y son frecuentes tanto en el ámbito comunitario como en el nosocomial. El objetivo de este estudio fue Identificar los principales agentes etiológicos y el perfil de resistencia a los antibióticos, presentado por los microorganismos más frecuentemente aislados de los urocultivos de pacientes con infección urinaria que acudieron al Laboratorio "Luis Razetti" Mérida -Venezuela, entre enero y junio de 2015. Este estudio fue de tipo observacional, de corte transversal y descriptivo. La población y muestra estuvo conformada por 149 pacientes de ambos sexos, cuyas muestras de orina fueron procesadas utilizado el método del asa calibrada y la identificación bacteriana mediante pruebas bioquímicas convencionales. La susceptibilidad antimicrobiana se determinó a través del método de difusión del disco en agar. Escherichia coli predominó en un 84,6 %, seguido de Proteus mirabilis y Enterococcus faecalis, ambos con (4,7 %). Los porcentajes más altos de resistencia para los aislados de E. coli, se observaron para ampicilina (92,06 %), ampicilina/sulbactam (68,25 %), ácido nalidíxico (38,89 %), ciprofloxacina (38,89 %) y trimetroprim­sulfametoxazol (54,76 %); y presentaron altos niveles de sensibilidad a Nitrofurantoína (80,95 %). El 5,15 % de las cepas de E. coli se mostraron fenotípicamente productoras de belalactamasa de espectro extendido y el 35,29 % de las otras Enterobacteriaceae aisladas, presentaron un perfil fenotípico compatible con la producción de la enzima Inhibitory-resistant TEM (IRT). Es importante destacar que estos estudios permiten conocer la etiología a de infecciones urinarias en la comunidad, así como los perfiles de resistencia y sensibilidad a nivel local, datos relevantes para establecer pautas de tratamiento empírico adaptadas a cada medio.


Urinary tract infections affect the human being throughout his life and are among the most frequent in both the community and nosocomial settings. The Aim of this study was to Identify the main etiological agents and antibiotic resistance profile presented by isolated microorganisms in the urocultures of patients with urinary tract infection who attended the Laboratory "Luis Razetti" Mérida -Venezuela, between January and June 2015. This study was observational, cross-sectional and descriptive. The population and sample consisted of 149 patients of both sexes, whose urine samples were processed using the calibrated handle method and bacterial identification through conventional biochemical tests. The antimicrobial susceptibility is determined through the disk diffusion method in agar. Escherichia coli dominated by 84.6 %, followed by Proteus mirabilis and Enterococcus faecalis, both with (4.7 %). The highest percentages of resistance for E. coli were observed for ampicillin (92.06 %), ampicillin/sulbactam (68.25 %), nalidixic acid (38.89 %), ciprofloxacin (38.89 %) trimetroprim-sulfamethoxazole (54.76 %); and had high levels of sensitivity to Nitrofurantoin (80.95 %). 5.15 % of E. coli strains were phenotypically producing extended-spectrum belalactamase and 35.29 % of others Enterobacteriaceae isolated had a phenotypic profile compatible with the production of the Enzyme Inhibitoryresistant TEM (IRT). It is important to note that these studies allow knowing the etiology of urinary tract infections in the community as well as resistance and sensitivity profiles at the local level, relevant data to establish empirical processing guidelines tailored to each medium.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Urinary Tract Infections/microbiology , Urinary Tract Infections/drug therapy , Drug Resistance, Bacterial , Escherichia coli/isolation & purification , Anti-Bacterial Agents/therapeutic use , Phenotype , Cross-Sectional Studies , Community-Acquired Infections/microbiology , Community-Acquired Infections/drug therapy , Escherichia coli/drug effects , Escherichia coli/genetics , Anti-Bacterial Agents/pharmacology
7.
Rev. chil. infectol ; 36(4): 447-454, ago. 2019. tab
Article in Spanish | LILACS | ID: biblio-1042661

ABSTRACT

Resumen Introducción: Escherichia coli es causa frecuente de un amplio espectro de infecciones, desde una infeccion urinaria no complicada hasta la sepsis grave y el choque septico, asociadas con desenlaces de alto impacto como ingreso a UCI y mortalidad. Objetivos: Determinar las diferencias en mortalidad. ingreso a UCI/UCE, presencia de cepas BLEE y tratamiento antimicrobiano en pacientes con sepsis grave y choque séptico por E. coli, con o sin bacteriemia, asi como su variabilidad dependiendo del foco infeccioso. Material y Métodos: Análisis secundario de estudio de cohorte prospective multicéntrico. Resultados: De 458 pacientes que tenian infeccion por E. coli, 123 tenian aislamiento solo en hemocultivo, 222 solo en urocultivo y 113 en ambas muestras. El aislamiento solo en hemocultivo se asocio mayor frecuencia de ingreso a UCI (n = 63; 5,2%). mayor necesidad de ventilacion mecánica (n = 19; 15,5%), mayor mortalidad y estancia hospitalaria (n = 22; 18%; mediana de 12 dias, RIQ= 7-17, respectivamente), pero con menor presencia de cepas productoras de BLEE en comparacion con urocultivos y hemocultivo, urocultivo (n = 20; 17,7% y n = 46; 20,7%, respectivamente). Recibieron tratamiento antimicrobiano en las primeras 24 h 424 pacientes (92,6%), con mas frecuencia piperacilina/ tazobactam (n = 256,60,3%). La proporcion de pacientes tratados empiricamente con carbapenemicos vs no carbapenemicos fue similar en los tres grupos. Discusión: El foco infeccioso. sumado a factores de nesgo para cepas productoras de BLEE, son herramientas utiles para definir pronostico y tratamiento en esta población, debido a la variabilidad clínica y microbiologica en los distintos aislados. Conclusión: Los pacientes con aislamiento de E. coli solo en hemocultivo presentan con mayor frecuencia desenlaces desfavorables en comparación con los pacientes con E. coli en urocultivo, con o sin bacteriemia. Llama la atencion en nuestro medio la menor cantidad de cepas productoras de BLEE en los pacientes con solo hemocultivo positivo.


Background: Escherichia coli is a common cause of a broad spectrum of infections, from non-complicated urinary tract infection, to severe sepsis and septic shock, that are associated to high impact outcomes, such as ICU admission and mortality. Aims: To establish differences in mortality, ICU admission, ESBL positive strains and antibiotic treatment, between patients with E. coli related severe sepsis and septic shock, with or without bacteremia and its variability based on the source of infection. Method: Secondary data analysis of a multicentric prospective cohort study. Results: From 458 patients with E. coli isolation, 123 had E. coli exclusively in blood culture, 222 solely in urine culture, and 113 in both samples. Escherichia coli isolation exclusively in blood culture was associated with higher frequency of ICU admission (n = 63; 51.2%), higher rate of mechanical ventilation requirement (n = 19; 15.5%), higher mortality and longer hospital stay (n = 22; 18%; median of 12 days, IQR= 7 - 17, respectively); but with a lower occurrence of ESBL strains, compared to patients with positive urine culture and positive blood/urine cultures (n = 20; 17.7% and n = 46; 20.7%, respectively). 424 patients (92.6%) received antibiotic treatment in the first 24 hours. The most commonly prescribed was piperacilin/tazobactam (n = 256;60.3%). The proportion of patients empirically treated with carbapenems vs non-carbapenems was similar in the three groups. Discussion: The source of infection, associated with ESBL strains risk factors, are useful tools to define prognosis and treatment in this population, because of their clinical and microbiological variability. Conclusion: Patients with E. coli isolation exclusively in the blood culture had higher frequency of non-favorable outcomes in comparison to patients with E. coli in urine culture with or without bacteremia. Additionally, in our population patients with E. coli solely in blood culture have lower prevalence of ESBL positive strains.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Shock, Septic/microbiology , Sepsis/microbiology , Emergency Service, Hospital/statistics & numerical data , Escherichia coli/isolation & purification , Escherichia coli Infections/mortality , Shock, Septic/mortality , Shock, Septic/drug therapy , Prospective Studies , Colombia/epidemiology , Sepsis/mortality , Sepsis/drug therapy , Escherichia coli/drug effects , Escherichia coli Infections/drug therapy
8.
Braz. j. infect. dis ; 23(3): 203-206, May-June 2019. graf
Article in English | LILACS | ID: biblio-1039226

ABSTRACT

ABSTRACT Global dissemination of mcr-like genes represents a serious threat to public health since it jeopardizes the effectiveness of colistin, an antibiotic used as a last-resort treatment against highly antibiotic-resistant bacteria. In 2017, a mcr-1-positive isolate of Escherichia coli was found in Chile for the first time. Herein we report the genetic features of this strain (UCO-457) by whole-genome sequencing (WGS) and conjugation experiments. The UCO-457 strain belonged to ST4204 and carried a 285 kb IncI2-type plasmid containing the mcr-1 gene. Moreover, this plasmid was transferred by conjugation to an E. coli J53 strain at high frequency. The isolate harbored the cma, iroN, and iss virulence genes and did carry resistance genes to trimethoprim/sulfamethoxazole and fluoroquinolones. Other antibiotic resistance determinants such as β-lactamases-encoding genes were not detected, making the isolate highly susceptible to these antibiotics. Our results revealed that such susceptible isolates could be acting as platforms to disseminate plasmid-mediated colistin resistance. Based on this evidence, we consider that mcr-like prevalence deserves urgent attention and should be examined not only in highly resistant bacteria but also in susceptible isolates.


Subject(s)
Humans , Escherichia coli Proteins/genetics , Escherichia coli/genetics , Escherichia coli Infections/microbiology , Outpatients , Chile , Escherichia coli/drug effects , Disk Diffusion Antimicrobial Tests , Anti-Bacterial Agents/pharmacology
9.
Arq. bras. oftalmol ; 82(1): 25-31, Jan.-Feb. 2019. tab
Article in English | LILACS | ID: biblio-973871

ABSTRACT

ABSTRACT Purpose: To compare effects of 5% topical povidone iodine with prophylactic topical azithromycin and moxifloxacin on bacterial flora in patients undergoing intravitreal injection. Methods: A total of 132 patients were randomly assigned to receive treatment with azithromycin or moxifloxacin, or no treatment (control group). In total, 528 specimens were obtained at the time of admission, 4 days before intravitreal injection, 4 days after intravitreal injection, and 8 days after intravitreal injection. Samples were immediately sent to the microbiology laboratory for incubation. Results: The microorganism observed most frequently was coagulasenegative Staphylococcus (23.8%). When the results of samples obtained on Day 4 before injection were assessed, growth of coagulase-negative Staphylococcus was significantly lower in the moxifloxacin group, compared with controls (p=0.049). Acinetobacter baumannii continued to grow after administration of azithromycin (p=0.033). When the results of four days after intravitreal injection were evaluated, growth of coagulase-ne gative Staphylococcus was higher in controls, compared with patients who received azithromycin or moxifloxacin (p=0.004). Eradication rate was significantly higher in the moxifloxacin group than in the control group (p=0.001). Samples obtained on Day 8 after intravitreal injection showed similar levels of bacterial growth in all groups (p=0.217). Conclusion: Moxifloxacin was more effective than 5% povidone iodine in controlling the growth of conjunctival bacterial flora. Use of moxifloxacin in combination with 5% povidone iodine resulted in a synergistic effect.


RESUMO Objetivo: Comparar os efeitos de iodopovidona tópico a 5% com azitromicina e moxifloxacina profiláticas sobre a flora bacteriana em pacientes submetidos à injeção intravítrea. Métodos: Um total de 132 pacientes foram aleatoriamente designados para receber tratamento com azitromicina ou moxifloxacina ou nenhum tratamento (grupo controle). No total, 528 amostras foram obtidas no momento na admissão, 4 dias antes da injeção intravítrea, 4 dias após a injeção intravítrea e 8 dias após a injeção intravítrea. As amostras foram imediatamente enviadas para o laboratório de microbiologia para incubação. Resultados: O microorganismo mais frequentemente observado foi o Staphylococcus coagulase-negativo (23,8%). Quando os resultados das amostras obtidas no dia 4 antes da injeção foram avaliados, o crescimento do Staphylococcus coagulase-negativo foi significativamente menor no grupo mo xifloxacina, em comparação com os controles (p=0,049). Acinetobacter baumannii continuou a crescer após a administração de azitromicina (p=0,033). Quando os resultados de 4 dias após a injeção intravítrea foram avaliados, o crescimento do Staphylococcus coagulase-negativo foi maior no controle, em comparação com pacientes que receberam azitromicina ou moxifloxacina (p=0,004). A taxa de erradicação também foi significativamente maior no grupo moxifloxacina do que no grupo controle (p=0,001). As amostras obtidas no dia 8 após injeção intravítrea mostraram níveis semelhantes de crescimento bacteriano em todos os grupos (p=0,217). Conclusão: A moxifloxacina foi mais eficaz do que 5% de iodopovidona no controle do crescimento da flora bacteriana conjuntival. O uso de moxifloxacina em combinação com 5% de iodopovidona resultou em um efeito sinérgico.


Subject(s)
Humans , Povidone-Iodine/administration & dosage , Azithromycin/administration & dosage , Conjunctiva/microbiology , Intravitreal Injections/methods , Moxifloxacin/administration & dosage , Anti-Infective Agents, Local/administration & dosage , Anti-Bacterial Agents/administration & dosage , Time Factors , Acinetobacter/isolation & purification , Acinetobacter/drug effects , Conjunctivitis, Bacterial/microbiology , Conjunctivitis, Bacterial/prevention & control , Endophthalmitis/microbiology , Endophthalmitis/prevention & control , Treatment Outcome , Conjunctiva/drug effects , Escherichia coli/isolation & purification , Escherichia coli/drug effects
10.
Braz. j. infect. dis ; 23(1): 15-21, Jan.-Feb. 2019. tab, graf
Article in English | LILACS | ID: biblio-1001499

ABSTRACT

ABSTRACT Objective: To evaluate the influence of sub-minimum inhibitory concentrations (MICs) of ciprofloxacin (CIP) on biofilm formation and virulence factors of Escherichia coli clinical isolates. Methods: Sub-MICs of CIP were determined using growth curve experiments. The biofilm-forming capacity of E. coli clinical isolates and E. coli ATCC 25922 treated or untreated with sub-MICs of CIP was assessed using a crystal violet staining assay. The biofilm structure of E. coli isolate was assessed with scanning electron microscopy (SEM). The expression levels of the virulence genes fim, usp, and iron and the biofilm formation genes of the pgaABCD locus were measured using quantification RT-PCR (qRT-PCR) in E. coli isolates and E. coli ATCC 25922. Results: Based on our results, the sub-MICs of CIP were 1/4 MICs. Sub-MICs of CIP significantly inhibited biofilm formation of E. coli clinical isolates and E. coli ATCC 25922 (p < 0.01). SEM analyses indicated that the biofilm structure of the E. coli changed significantly after treatment with sub-MICs of CIP. Expression levels of the virulence genes fim, usp, and iron and the biofilm formation genes of the pgaABCD locus were also suppressed. Conclusions: The results revealed that treatment with sub-MICs of CIP for 24 h inhibited biofilm formation and reduced the expression of virulence genes and biofilm formation genes in E. coli.


Subject(s)
Ciprofloxacin/pharmacology , Biofilms/drug effects , Virulence Factors , Escherichia coli/drug effects , Escherichia coli/genetics , Anti-Bacterial Agents/pharmacology , Reference Values , Time Factors , Microscopy, Electron, Scanning , Microbial Sensitivity Tests , Gene Expression/drug effects , Reverse Transcriptase Polymerase Chain Reaction , Gentian Violet
11.
Arq. gastroenterol ; 55(4): 390-396, Oct.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-983850

ABSTRACT

ABSTRACT BACKGROUND: Enteroaggregative Escherichia coli (EAEC) is one of the main acute and chronic diarrhea causes both in children and adults, mainly in developing countries. OBJECTIVE: The aim of the present study is to characterize EAEC strains isolated from faecal samples and to identify genes potentially contributing to virulence, biofilm production and antimicrobial resistance in children admitted to a pediatric hospital in Porto Velho, Rondônia State. METHODS: The total of 1,625 E. coli specimens were isolated from 591 children in the age group 6 years or younger who were hospitalized in Cosme and Damião Children Hospital in Porto Velho, between February 2010 and February 2012, with acute gastroenteritis. Colonies suggestive of E. coli were subjected to polymerase chain reaction testing in order to identify the virulence factors. The in vitro adhesion assays using HEp-2 adherence were tests. Biofilm detection through spectrophotometry and antimicrobial susceptibility tests were conducted in the disk diffusion method. RESULTS: The mentioned study examined 591 stool samples from children with diarrhea. Diarrheogenic E. coli was found in 27.4% (162/591) of the children. EAEC was the diarreagenic E. coli most frequently associated with diarrhea 52.4% (85/162), which was followed by enteropathogenic E. coli 43.8% (71/162), enterotoxigenic E. coli 2.4% (4/162), and enterohemorrhagic E. coli 1.2% (2/162). The aggR gene was detected in 63.5% (54/85) of EAEC isolates; moreover, statistically significant correlation was observed among typical EAEC (aggR) and aatA (P<0.0001), irp2 (P=0.0357) and shf (P=0.0328). It was recorded that 69% (59/85) of the 85 analyzed EAEC strains were biofilm producers; 73% (43/59) of the biofilm producers carried the aggR gene versus 42.3% (11/26) of non-producers (P=0.0135). In addition, there was association between the aatA gene and biofilm production; 61% (36/59) of the samples presented producer strains, versus 19.2% (5/26) of non-producers (P<0.0004). Antibiotic sensitivity test evidenced that most EAEC were ampicillin 70.6% (60/85), sulfamethoxazole 60% (51/85), tetracycline 44.7% (38/85) and cefotaxime 22.4% (19/85) resistant. CONCLUSION: As far as it is known, the present study is pioneer in Northern Brazil to investigate EAEC virulence factors and to show the antimicrobial susceptibility of EAEC strains isolated from children with diarrhea.


RESUMO CONTEXTO: A Escherichia coli enteroagregativa (EAEC) é um dos principais agentes causadores de diarreia aguda e crônica em crianças e adultos, principalmente em países em desenvolvimento. OBJETIVO: Caracterizar cepas de EAEC isoladas de amostras fecais e identificar genes que potencialmente contribuem para a virulência, produção de biofilme e resistência antimicrobiana em crianças internadas em um hospital pediátrico em Porto Velho, Rondônia. MÉTODOS: Um total de 1.625 cepas de E. coli foram isolados de 591 crianças com gastroenterite aguda na faixa etária de 6 anos que foram internadas no Hospital Infantil Cosme e Damião na cidade de Porto Velho, entre fevereiro de 2010 e fevereiro de 2012. Colônias sugestivas de E. coli foram submetidas a reação em cadeia da polimerase para identificação de fatores de virulência. O ensaio de adesão in vitro foi desenvolvido com célula HEp-2. A detecção de biofilme foi realizada através do teste de espectrofotometria e os testes de susceptibilidade aos antimicrobiana foram realizados através do método de difusão em disco. RESULTADOS: A E. coli diarreiogênica foi encontrada em 27,4% (162/591) das crianças e a EAEC foi a E. coli diarreiogênica mais frequentemente associada à diarreia com 52,4% (85/162), seguida pela E. coli enteropatogênica 43,8% (71/162), E. coli enterotoxigênica 2,4% (4/162) e E. coli enterohemorrágica 1,2% (2/162). O gene aggR foi detectado em 63,5% (54/85) dos isolados de EAEC com correlação estatisticamente significante entre esse gene com os genes aatA (P<0,0001), irp2 (P=0,0357) e shf (P=0,0328). Neste estudo 69% (59/85) das cepas de EAEC eram produtoras de biofilme, destas 73% (43/59) possuíam o gene aggR, ao passo que entre as não produtoras 42,3% (11/26) possuíam o gene (P=0,0135). Essa associação também foi observada com o gene aatA, presente em 61% (36/59) das cepas produtoras e em 19,2% (5/26) das não produtoras (P<0,0004). O teste de sensibilidade aos antibimicrobianos evidenciou que a maioria das EAEC eram resistentes a ampicilina 70,6% (60/85), ao sulfametoxazol 60% (51/85), a tetraciclina 44,7% (38/85) e a cefotaxima 22,4% (19/85). CONCLUSÃO: Este é o primeiro estudo no Norte do Brasil sobre a investigação dos fatores de virulência de EAEC mostrando a susceptibilidade antimicrobiana de cepas de EAEC isoladas de crianças com diarreia.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Biofilms/growth & development , Diarrhea/microbiology , Escherichia coli/isolation & purification , Escherichia coli/physiology , Escherichia coli Infections/microbiology , Virulence/genetics , Brazil/epidemiology , Microbial Sensitivity Tests , Polymerase Chain Reaction , Prevalence , Diarrhea/epidemiology , Escherichia coli/drug effects , Escherichia coli Infections/epidemiology , Feces/microbiology , Genes, Bacterial/genetics
13.
Article in Spanish | LILACS | ID: biblio-1007328

ABSTRACT

Propolis is a substance manufactured by Apis mellifera and has been widely used in folk medicine due to its high concentration of bioactive compounds. The purpose of the following study was to characterize and evaluate in vitro the antimicrobial properties of propolis on clinical samples and ATCC strains. The chemical characterization of propolis presents a concentration of total polyphenols of 247 ± 9 mg EAG g-1 MS, flavones and flavonols 75± 4 mg EQ g-1 MS, flavanonones and flavanonols 118 ± 11 EP g-1 MS. HPLC-DAD identified apigenin, galangin, phenethyl ester of caffeic acid and pinocembrin, in addition to 16 compounds by HPLC MS/MS. Chilean propolis is a natural antimicrobial, showing effectiveness in strains ATCC Staphylococcus aureus, Candida albicans, Trichophyton rubrum and clinical samples of Staphylococcus aureus unlike Escherichia coli. These results demonstrate the antimicrobial effectiveness of the synergy of compounds present in propolis against different human pathogens.


El propóleos es una substancia fabricada por Apis mellifera y ha sido utilizado ampliamente en la medicina popular debido a su alta concentración de compuestos bioactivos. El propósito del siguiente estudio fue caracterizar y evaluar in vitro las propiedades antimicrobianas del propóleos sobre muestras clínicas y cepas ATCC. La caracterización química de propóleos presenta una concentración de polifenoles totales de 247 ± 9 mg EAG g-1 de MS, flavonas y flavonoles 75 ± 4 mg EQ g-1 de MS, flavanononas y flavanonoles 118 ± 11 EP g-1 de MS. Mediante HPLC-DAD se identificó apigenina, galangina, fenetil éster del ácido cafeico y pinocembrina, además de 16 compuestos mediante HPLC MS/MS. El propóleos chileno es un antimicrobiano natural, observándose efectividad en cepas ATCC Staphylococcus aureus, Candida albicans, Trichophyton rubrum y muestras clínicas de Staphylococcus aureus a diferencia de Escherichia coli. Estos resultados demuestran la efectividad antimicrobiana de la sinergia de compuestos presentes en el propóleos ante diferentes patógenos humanos.


Subject(s)
Humans , Propolis/pharmacology , Staphylococcus aureus/drug effects , Candida albicans/drug effects , Escherichia coli/drug effects , Anti-Infective Agents/pharmacology , Pharynx/microbiology , Propolis/chemistry , Trichophyton/drug effects , Flavonoids/analysis , Microbial Sensitivity Tests , Apis mellifica , Chile , Chromatography, High Pressure Liquid , Escherichia coli/drug effects , Gas Chromatography-Mass Spectrometry , Anti-Infective Agents/chemistry , Mouth/microbiology
14.
West Indian med. j ; 67(4): 344-349, Oct.-Dec. 2018. tab
Article in English | LILACS | ID: biblio-1045862

ABSTRACT

ABSTRACT Objective: To determine the role of extended-spectrum β-lactamases in carbapenem-resistant Gram-negative bacteria from south-western Nigeria. Methods: Twenty-seven carbapenem-resistant isolates that were found to be non-carbapenemase producers (15 Escherichia coli, 9 Klebsiella pneumoniae and 3 Pseudomonas aeruginosa) were further studied. These isolates were subjected to analysis including phenotypic and genotypic detection of various β-lactamases, efflux activity, outer membrane protein, plasmids replicon typing, detection of transferable genes and resistances and typing using random amplified polymorphic DNA tests. Results: No isolates demonstrated de-repression of efflux, but all showed either complete loss or reduced production of outer membrane proteins. Transconjugants from these strains contained various genes including plasmid-mediated quinolone resistance and extended-spectrum beta-lactamases. All the transconjugants carried the blaCTX-M-15 gene. The transconjugants had varying minimum inhibitory concentrations of carbapenems ranging from 0.03 μg/ml to 8 μg/ml. Varying resistances to other antimicrobial agents were also transferred with the plasmids. The donor isolates were not clonally related by molecular typing. Conclusion: Resistance to carbapenem antibiotics in this sample was not mediated only by carbapenemases but also by production of extended-spectrum β-lactamases (largely CTX-M-15), accompanied by protein loss. This was an important mechanism underpinning carbapenem resistance in these clinical isolates of various species.


RESUMEN Objetivo: Determinar el papel de las betalactamasas de espectro extendido en la resistencia al carbapenem en las bacterias gramnegativas en Nigeria. Métodos: Veintisiete aislados resistentes al carbapenem que fueron hallados productores de no carbapenemasas (15 Escherichia coli, 9 Klebsiella pneumoniae, y 3 Pseudomonas aeruginosa) fueron estudiados con mayor profundidad. Estos aislados fueron sometidos a análisis incluyendo la detección fenotípica y genotípica de varias betalactamasas, la actividad de eflujo, las porinas de la membrana externa, la tipificación del replicón plasmídico, la detección de genes transferibles y resistencias y tipificación usando pruebas de ADN polimórficas amplificadas aleatorias. Resultados: Ninguno de los aislamientos mostró desrepresión de eflujo, pero todos demostraron la pérdida completa o la producción reducida de porinas externas de la membrana. Los transconjugantes de estas cepas contenían varios genes incluyendo resistencia a la quinolona mediada por plásmidos y betalactamasas de espectro extendido. Todos los transconjugantes portaban el gen blaCTX-M-15. Los transconjugantes tenían diversas concentraciones inhibitorias mínimas de carbapenemas que oscilaban entre 0.03 μg/ml y 8 μg/ml. Varias resistencias a otros agentes antimicrobianos fueron también transferidas con los plásmidos. Los aislamientos del donante no estuvieron relacionados clonalmente por tipificación molecular. Conclusión: La resistencia al antibiótico carbapenem en esta muestra no fue mediada solamente por las carbapenemasas, sino también por la producción de betalactamasas de espectro extendido (en gran parte CTX-M-15), acompañado por pérdida de porina. Éste era un mecanismo importante que sustentaba la resistencia al carbapenem en estos aislados clínicos de varias especies.


Subject(s)
Humans , Pseudomonas aeruginosa/drug effects , beta-Lactamases/biosynthesis , Escherichia coli/drug effects , Klebsiella pneumoniae/drug effects , Anti-Bacterial Agents/pharmacology , Phenotype , Pseudomonas aeruginosa/enzymology , Drug Resistance, Microbial , Microbial Sensitivity Tests , Escherichia coli/enzymology , Genotype , Klebsiella pneumoniae/enzymology , Nigeria
15.
Braz. j. microbiol ; 49(3): 569-574, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951794

ABSTRACT

Abstract Multidrug-resistant microorganisms are of great concern to public health. Genetic mobile elements, such as plasmids, are among the most relevant mechanisms by which bacteria achieve this resistance. We obtained an Escherichia coli strain CM6, isolated from cattle presenting severe diarrheic symptoms in the State of Querétaro, Mexico. It was found to contain a 70 kb plasmid (pMEX01) with a high similarity to the pHK01-like plasmids that were previously identified and described in Hong Kong. Analysis of the pMEX01 sequence revealed the presence of a blaCTX-M-14 gene, which is responsible for conferring resistance to multiple β-lactam antibiotics. Several genes putatively involved in the conjugative transfer were also identified on the plasmid. The strain CM6 is of high epidemiological concern because it not only displays resistance to multiple β-lactam antibiotics but also to other kinds of antibiotics.


Subject(s)
Animals , Cattle , Plasmids/genetics , Cattle Diseases/microbiology , Drug Resistance, Bacterial , beta-Lactams/pharmacology , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli Infections/veterinary , Anti-Bacterial Agents/pharmacology , Plasmids/metabolism , beta-Lactamases/genetics , beta-Lactamases/metabolism , Microbial Sensitivity Tests , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Escherichia coli/metabolism , Escherichia coli Infections/microbiology , Mexico
16.
Braz. j. microbiol ; 49(3): 656-661, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951809

ABSTRACT

Abstract Hamelia patens, is a plant traditionally used to treat a variety of conditions among the Huastec people of Mexico. The objective of this study is to characterize the phenolic content and critically examine the antimicrobial activity of leaf extracts H. patens, obtained by maceration, Soxhlet and percolation, using ethanol as 70% solvent. Phenolic compounds are characterized by liquid chromatography, coupled to a High Resolution Mass Spectrometry, and the antimicrobial activity was studied from the inhibitory effect of each extract for Escherichia coli, Staphylococcus aureus, Salmonella typhi and S. paratyphi, and by the Minimum Bactericidal Concentration, the percentage of activity and the Index of Bacterial Susceptibility of each extract. The phenolic compound identified in different concentrations in the three extracts was epicatechin. The extracts obtained by the three methods had antimicrobial activity, however, there was no significant difference (p < 0.05) between the Minimum Bactericidal Concentration of the extracts obtained by maceration, percolation and Soxhlet. The results of this study contribute to the body of knowledge on the use of extracts in controlling microorganisms with natural antimicrobials.


Subject(s)
Phenols/isolation & purification , Phenols/pharmacokinetics , Plant Extracts/isolation & purification , Plant Extracts/pharmacokinetics , Hamelia/chemistry , Chemical Fractionation/methods , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Phenols/chemistry , Staphylococcus aureus/drug effects , Plant Extracts/chemistry , Microbial Sensitivity Tests , Escherichia coli/drug effects , Mexico , Anti-Bacterial Agents/chemistry
17.
Braz. j. microbiol ; 49(3): 471-480, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951821

ABSTRACT

Abstract Escalating burden of antibiotic resistance that has reached new heights present a grave concern to mankind. As the problem is no longer confined to clinics, we hereby report identification of a pandrug resistant Escherichia coli isolate from heavily polluted Delhi stretch of river Yamuna, India. E. coli MRC11 was found sensitive only to tobramycin against 21 antibiotics tested, with minimum inhibitory concentration values >256 µg/mL for amoxicillin, carbenicillin, aztreonam, ceftazidime and cefotaxime. Addition of certain heavy metals at higher concentrations were ineffective in increasing susceptibility of E. coli MRC11 to antibiotics. Withstanding sub-optimal concentration of cefotaxime (10 µg/mL) and mercuric chloride (2 µg/mL), and also resistance to their combinatorial use, indicates better adaptability in heavily polluted environment through clustering and expression of resistance genes. Interestingly, E. coli MRC11 harbours two different variants of blaTEM (blaTEM-116 and blaTEM-1 with and without extended-spectrum activity, respectively), in addition to mer operon (merB, merP and merT) genes. Studies employing conjugation, confirmed localization of blaTEM-116, merP and merT genes on the conjugative plasmid. Understanding potentialities of such isolates will help in determining risk factors attributing pandrug resistance and strengthening strategic development of new and effective antimicrobial agents.


Subject(s)
Metals, Heavy/pharmacology , Drug Resistance, Multiple, Bacterial , Rivers/microbiology , Escherichia coli/drug effects , Anti-Bacterial Agents/pharmacology , Operon , beta-Lactamases/genetics , beta-Lactamases/metabolism , Microbial Sensitivity Tests , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Escherichia coli/isolation & purification , Escherichia coli/enzymology , Escherichia coli/genetics , India
18.
Rev. Soc. Bras. Med. Trop ; 51(4): 533-536, July-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-1041470

ABSTRACT

Abstract INTRODUCTION This aim of this study was to evaluate the antibacterial activity of fractions and isolates of Maytenus guianensis, a plant species used in Amazonian folk medicine. METHODS A disk diffusion technique was used to investigate the antibacterial potential. RESULTS The hexanic fractions and tingenone B isolate showed inhibitory effects against Staphylococcus aureus and Streptococcus pneumoniae. CONCLUSIONS These results indicate the antibacterial potential of this species and will enable future studies to identify novel therapeutic alternatives from this species.


Subject(s)
Staphylococcus aureus/drug effects , Streptococcus pneumoniae , Plant Extracts/pharmacology , Maytenus/chemistry , Escherichia coli/drug effects , Klebsiella pneumoniae/drug effects , Anti-Bacterial Agents/pharmacology , Disk Diffusion Antimicrobial Tests , Anti-Bacterial Agents/isolation & purification
20.
Rev. chil. infectol ; 35(4): 343-350, ago. 2018. tab
Article in Spanish | LILACS | ID: biblio-978043

ABSTRACT

Resumen Introducción: En las infecciones por enterobacterias productoras de β-lactamasas de espectro extendido (BLEE), los β-lactámicos preferidos para tratamiento son los carbapenémicos. Sin embargo, estudios clínicos muestran eficacia de piperacilina/tazobactam en ciertas infecciones por Escherichia coli productoras de BLEE. Objetivo: Determinar la cura clínica y microbiológica con piperacilina/tazobactam en pacientes con infecciones por E. coli productoras de BLEE, tipo CTX-M. Materiales/Métodos: Estudio descriptivo, retrospectivo, con adultos internados en un hospital universitario. Incluimos infecciones del tracto urinario (ITU), intra-abdominales (IIA) e infecciones de tejidos blandos (ITB). Resultados: Estudiamos 40 pacientes, donde 65% correspondían a ITU, 25% IIA y 10 % ITB. La cura clínica global se logró en 89,4%, con mejores resultados en las ITU (100%), seguidas de ITB (80%) e IIA (70%). El 85% de las cepas tenía concentraciones inhibitorias mínimas (CIM) ≤ 8 μg/mL y 70% con CIM ≤ 4 μg/mL. La tasa de fracaso fue mayor en las infecciones con inóculos altos intraabdominales. La BLEE del tipo CTX-M-15 se encontró en 62,5%. Conclusiones: Piperacilina/tazobactam logró cura clínica y microbiológica, en pacientes con infecciones por E. coli productoras de BLEE susceptibles, especialmente en ITU e IPB y en menor medida en IIA.


Background: Carbapenems are the preferred β-lactamics for treatment for infections caused by enterobacteria producing extended-spectrum β-lactamases (ESBL); however, clinical studies show effectiveness of piperacillin/tazobactam in certain infections by Escherichia coli ESBL producers. Aim: To determine the clinical and micro-biological cure with piperacillin/tazobactam in patients with infections caused by E. coli ESBL producers, CTXM type. Methods: Retrospective descriptive study with adults hospitalized in a university hospital. We included urinary tract infections (UTI), intra-abdominal infections (IAI), soft tissue infections (STI) and/or bacteremia. Results: We studied 40 patients, where 65% corresponded to UTI, 25% to IAI and 10% were STI. The overall clinical cure was achieved in 89.4%, with the best results in the ITU (100%), followed by STI (80%) and 70% in IAI. The 85% of the strains had minimum inhibitory concentrations (MIC) ≤8 μg/ml and 70% with MIC ≤4 μg/mL, however the rate of failure were high in intra-abdominal infections with high inocula or not controlled; CTX-M-15 was found in the 62.5%. Conclusions: Piperacillin/tazobactam was efficient to obtain clinical and microbiological cure in patients with infections caused by ESBL producers but susceptible E. coli, especially in UTI and STI and to a lesser extent in IAI.


Subject(s)
Humans , Male , Female , Adult , Aged , beta-Lactamases/drug effects , Escherichia coli Proteins/drug effects , Escherichia coli Infections/drug therapy , Piperacillin, Tazobactam Drug Combination/therapeutic use , Anti-Bacterial Agents/therapeutic use , Retrospective Studies , Treatment Outcome , Escherichia coli/isolation & purification , Escherichia coli/drug effects , Escherichia coli Infections/enzymology , Escherichia coli Infections/microbiology
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