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1.
Int. microbiol ; 22(1): 131-141, mar. 2019. graf, tab
Artigo em Inglês | IBECS | ID: ibc-184821

RESUMO

The relationships between specific type IV pili (TFP) groups and antibiotic resistance, biofilm formation, and bacterial motility were determined in 190 Pseudomonas aeruginosa clinical isolates. While motility and biofilm formation were determined by phenotypic assays, the presence of TFP was determined by PCR assay and antibiotic susceptibility by disk diffusion. The results showed a high ability to form biofilm (97.4%), multidrug resistance (44.7%), and the presence of a high number of motile isolates. We also found an association between strong biofilm production and multidrug resistance. Furthermore, TFP group III was associated with strong biofilm production. In contrast, the isolates with TFP group II and those without any TFP were associated with non-strong biofilm production. Regarding motility, TFP group II was associated with higher percentages of swarming, swimming, and twitching, while TFP group I showed lower percentages of swarming and twitching, and TFP group III showed lower levels of swarming and swimming. In conclusion, these findings highlight the differences in P. aeruginosa phenotypes related to the presence of specific TFP groups and their potential implications in clinical settings


No disponible


Assuntos
Humanos , Biofilmes/crescimento & desenvolvimento , Fímbrias Bacterianas/fisiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Locomoção , Pseudomonas aeruginosa/fisiologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Reação em Cadeia da Polimerase , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética
2.
Int. microbiol ; 18(3): 151-157, sept. 2015. ilus
Artigo em Inglês | IBECS | ID: ibc-152255

RESUMO

In nature, highly efficient and diverse consortia of microbes cycle carbon and other elements while generating energy for growth. Driving these reactions are organisms with the ability to extract electrons from the chemical substrates and transfer them to insoluble and soluble electron acceptors. One bacterial group in particular, Geobacter spp., can couple their respiratory metabolism to the reduction of insoluble minerals, such as iron and manganese oxides, and soluble toxic metals such as uranium. Key to these activities is the ability of the cells to transfer respiratory electrons extracellularly using an electroactive cell envelope containing abundant metalloproteins, including c-cytochromes, and conductive protein appendages or pili (known as nanowires). Thus, in addition to been ecological drivers of the cycling of carbon and metals in nature, these organisms show promise for the bioremediation of environments impacted with toxic metals. The electrical activity of Geobacter can also be mimicked in electrochemical reactors equipped with an electrode poised at a metabolically oxidizing potential, so that the electrode functions as an unlimited sink of electrons to drive the oxidation of electron donors and support cell growth. Electrochemical reactors are promising for the treatments of agricultural, industrial, and human wastes, and the electroactivity of these microbes can be used to develop materials and devices for bioenergy and bioremediation applications (AU)


No disponible


Assuntos
Biorremediação (Saúde Ambiental)/métodos , Geobacter , Reatores Biológicos , Nanofios/microbiologia , Grupo dos Citocromos c/análise , Fímbrias Bacterianas/microbiologia , Fontes de Energia Bioelétrica/microbiologia
3.
Med. oral patol. oral cir. bucal (Internet) ; 18(1): 100-105, ene. 2013. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-108229

RESUMO

Objective: The goal of this study was to determine the genetic variability of the fimA gene in Porphyromonas gingivalis isolates from Spanish patients. Study Design: Pooled subgingival samples were taken, processed and cultured in non-selective blood agar medium. Pure cultures of one to six isolates per patient were obtained and PCR and PCR-RFLP were used for fimbrillin gene (fimA) type determination of the extracted genomic (DNA). Results: Two hundred and twenty four Porphyromonas gingivalis isolates from 65 patients were analyzed consisting of 15 non-periodontitis patients (66 isolates) and 50 with periodontitis (158 isolates). Genotype II was the most prevalent (50.9%), while the other types of fimbriae did not exceed fifteen percent of prevalence. Isolates with types II and IV of fimbriae were significantly more prevalent in periodontitis patients than isolates with genotype I. Co-infection was observed in 17.65% of the patients analyzed. Conclusion: The results suggest that in this population Porphyromonas gingivalis with type II of fimbriae are significantly more predominant in periodontitis patients than genotype I (AU)


No disponible


Assuntos
Humanos , Porphyromonas gingivalis/genética , Periodontite/microbiologia , Infecções por Bacteroidaceae/microbiologia , Fímbrias Bacterianas/genética
4.
Actas urol. esp ; 36(1): 48-53, ene. 2012.
Artigo em Espanhol | IBECS | ID: ibc-96197

RESUMO

Contexto: En este artículo se revisan diferentes aspectos acerca de la prevención de las infecciones del tracto urinario que incluyen: la confirmación de la existencia de dichas infecciones, la aplicación de medidas higiénico-dietéticas, la profilaxis antibacteriana-preferentemente la toma de una única dosis nocturna diaria oral de un antibiótico o quimioterápico con elevada excreción urinaria y buena tolerancia-, la administración de vacunas elaboradas con Escherichiacoli y otros bacilos gramnegativos completos con fracciones inmunoestimulantes o fimbrias tipo 1 de E. coli por vías parenteral u oral. Objetivo: Revisión de las nuevas medidas de prevención de las infecciones del tracto urinario. Adquisición y síntesis de evidencia: Se revisan diferentes aspectos microbiológicos, la fisiopatología y los factores de virulencia de E. coli uropatógenos productores de fimbrias de tipos 1y P. Se analiza la relación entre los grupos sanguíneos y la infección del tracto urinario en los individuos secretores y no secretores. Conclusiones: El uso de vacunas inactivadas con fenol y administradas por vía mucosa, el empleode inhibidores de la adherencia y de la formación de biopelículas bacterianas y el uso de estimuladores del adenosín-monofosfato cíclico se presentan como nuevas medidas preventivas de la infección urinaria, particularmente para el grupo de mayor incidencia, representado por las mujeres entre la pubertad y la menopausia (AU)


Context: This article reviews diverse aspects of the prevention of urinary tract infections, including confirmation of the diagnosis, application of hygiene and dietary measures, antibacterial prophylaxis (preferably consisting of a single nocturnal oral dose per day of an antibiotic or drug with high urinary excretion and good tolerance), and administration of vaccines made with Escherichia coli and other Gram-negative bacilli, consisting of immunostimulating fractions of E. coli strains or E. coli type-1 fimbriae administered through the parenteral or oral route. Objective: We aimed to review the new preventive measures against urinary tract infections. Acquisition and synthesis of evidence: We reviewed various microbiological aspects, as well as the physiopathology and virulence factors of uropathogenic E. coli strains expressing type-1 and P fimbriae. The association between blood groups and urinary tract infections in blood group antigen-secretors and non secretors was analyzed. Conclusions: New preventive measures against urinary tract infection consist of the use of phenol-inactivated vaccines administered via the mucosal route, inhibitors of bacterial adherence and biofilm formation and cyclic adenosine monophosphate stimulators, especially in women aged between puberty and menopause, who show the highest incidence of these infections (AU)


Assuntos
Humanos , Feminino , Infecções Urinárias/prevenção & controle , Antibioticoprofilaxia , Infecções por Escherichia coli/prevenção & controle , Avaliação de Resultado de Ações Preventivas/métodos , Vacinas contra Escherichia coli , Fímbrias Bacterianas/microbiologia , Biofilmes
6.
Int. microbiol ; 12(4): 243-251, dic. 2009. tab
Artigo em Inglês | IBECS | ID: ibc-77877

RESUMO

A collection of 69 eae-positive strains expressing 29 different intimin types and eight tir alleles was characterized with respect to their adherence patterns to HeLa cells, ability to promote actin accumulation in vitro, the presence of bfpA alleles in positive strains, and bundle-forming pilus (BFP) expression. All of the nine typical enteropathogenic Escherichia coli (tEPEC) studied harbored the enteropathogenic E. coli adherence factor (EAF) plasmid, as shown by PCR and/or EAF probe results. In addition, they were positive for bfpA, as shown by PCR, and BFP expression, as confirmed by immunofluorescence (IFL) and/or immunoblotting (IBL) assays. Localized adherence (LA) was exclusively displayed by those nine tEPEC, while localized-adherence-like (LAL) was the most frequent pattern among atypical EPEC (aEPEC) and Shiga-toxinproducing E. coli (STEC). All LA and LAL strains were able to cause attaching and effacing (AE) lesions, as established by means of the FAS test. There was a significant association between the presence of tir allele alpha1 and bfpA-positive strains, and consequently, with the LA pattern. However, intimin type or bfpA was not associated with the adherence pattern displayed in HeLa cells. Among the eight bfpA alleles detected, a new type (beta10; accession number FN391178) was identified in a strain of serotype O157:H45, and a truncated variant (beta3.2-t; accession number FN 391181) in four strains belonging to different pathotypes (AU)


No disponible


Assuntos
Humanos , Aderência Bacteriana , Actinas/metabolismo , Escherichia coli Enteropatogênica/patogenicidade , Escherichia coli Shiga Toxigênica/patogenicidade , Alelos , Fímbrias Bacterianas/fisiologia , Proteínas de Escherichia coli/genética , DNA Bacteriano/genética , Genótipo , Células HeLa , Microscopia de Fluorescência , Reação em Cadeia da Polimerase , Plasmídeos
7.
Sanid. mil ; 65(4): 246-258, oct.-dic. 2009. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-87063

RESUMO

Bacterial biofilms are stratified microbial communities imbibed in an extracellular polymer and adhered to a solid surface in an aquatic environment. They might be integrated by one or several species and are organized in complex communities selfregulated by an efficient communication system. They protect themselves against hostile agents assembling with their own materials a peculiar architecture with an interior network of channels guaranteeing the supply of water, nutrients and gases to the majority of its components. Moreover, through the modulation of these chemical signals, individual cells or small groups detach themselves and occupy new grounds initiating the slow but inexorable invasion of a habitat. The damage to the warships’ hull; biocorrosion of the weaponry and other alloy materials –or non metallic ones– susceptible to moisture; biodegradation of excess of trinitrotoluene; foodborne diseases due to cross contaminations; oral pathologies; persistent infections in chronic wounds; contamination of the water supply in military barracks; development of slime on the walls of the water tanks, in cisterns or fountains of the military barracks dining-halls; persistence of Legionella spp in the cooling towers or the antibiotic resistance in infections after implantation of joint prosthesis or any other clinical device; these are frequent situations in which biofilm-producing microorganisms participate in their emergence and evolution. In this article the different phases leading to their development are described, the regulation mechanisms and the strategies that allow their survival in a hostile environment against the action of the biocides or the immune response of the host (AU)


Los biofilmes bacterianos o biopelículas son comunidades estratificadas de células embebidas en un polímero extracelular y adheridas a una superficie sólida en un medio acuático; están constituidos por una única especie o por especies diferentes. Se organizan en comunidades complejas autorreguladas gracias a un eficaz sistema de comunicación, protegiéndose frente a los agentes hostiles mediante la construcción con materiales propios, de una estructura de arquitectura particular y dotada de una red interior de canalizaciones, que garantiza el abastecimiento de agua, nutrientes y gases a la mayoría de los integrantes. Además, a través de modificaciones de estas señales químicas, células individuales o pequeños grupos se destacan en avanzadas sobre el terreno y, tras afianzarse sobre la posición, retoman la pausada pero inexorable invasión de un hábitat. El deterioro de los cascos de los buques de guerra; la biocorrosión del armamento y de otros materiales de aleación −o no metálicos− susceptibles de humedecerse; la biodegradación de excedentes de trinitrotolueno; la presentación de infecciones alimentarias por contaminaciones cruzadas; la incidencia de patologías bucodentales; las infecciones pertinaces en las heridas crónicas; la contaminación de las redes de distribución de agua de los acuartelamientos; la aparición de limos en las paredes de los depósitos de instalaciones interiores, en los aljibes o en las fuentes de los comedores colectivos militares; la persistencia de Legionella spp. en las torres de refrigeración o la antibiorresistencia de infecciones surgidas tras la implantación de prótesis articulares o de cualquier otro dispositivo de uso clínico, son situaciones frecuentes en cuya gestación y evolución posterior, intervienen microorganismos formando biofilmes. En este trabajo se describen las distintas etapas que conducen a su desarrollo, los mecanismos de regulación y las estrategias que les permiten sobrevivir en un medio desfavorable, venciendo la acción de los biocidas o la respuesta inmunitaria del hospedador (AU)


Assuntos
Biofilmes/crescimento & desenvolvimento , Biodiversidade , Aderência Bacteriana/fisiologia , Adesinas Bacterianas , Praguicidas/farmacocinética , Fímbrias Bacterianas , Lectinas
8.
Int. microbiol ; 9(4): 241-246, dic. 2006. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-055831

RESUMO

Fimbrial extracts from porcine enterotoxigenic Escherichia coli (ETEC) strains carrying F6 (987P) intestinal colonization factor antigen were obtained using the thermal shock method. The extracts were analyzed by SDSPAGE and immunoblotting using different fimbriae-specific antisera. Two major protein bands with molecular masses of 17.5 and 21.9 kDa were detected. The 21.9-kDa band was identified as the major subunit of F6 fimbrial antigen in strains of serogroups O9 and O141. The 17.5-kDa band was associated with porcine strains of serogroups O9 and O20 (AU)


Los extractos de fimbrias obtenidos usando el método de choque térmico a partir de cepas de origen porcino de Escherichia coli (ETEC) enterotoxigénica con el antígeno de colonización intestinal F6 (987P) fueron analizados por SDS-PAGE e immunotransferencia usando diferentes antisueros específicos frente a antígenos de fimbrias. Se detectaron dos bandas principales de proteínas de 17,5 kDa y 21,9 kDa según la cepa ensayada. La banda de 21,9 kDa fue identificada como la subunidad estructural principal del antígeno de fimbria F6 y se observó en las cepas de los serogrupos O9 yO141. La banda de 17,5 kDa se asoció a las cepas porcinas de los serogrupos O9 y O20 (AU)


Assuntos
Animais , Escherichia coli/patogenicidade , Infecções por Escherichia coli/microbiologia , Fímbrias Bacterianas/microbiologia , Suínos/microbiologia , Diarreia/microbiologia
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