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1.
J Neuroinflammation ; 11: 8, 2014 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-24410883

RESUMO

BACKGROUND: The innate immune response is the first line of defence against invading microorganisms and it is also activated in different neurologic/neurodegenerative pathological scenarios. As a result, the family of the innate immune toll-like receptors (TLRs) and, in particular, the genetic/pharmacological manipulation of the TLR-4 signalling pathway emerges as a potential therapeutic strategy. Growing evidence relates stress exposure with altered immune responses, but the precise role of TLR-4 remains partly unknown. METHODS: The present study aimed to elucidate whether the elements of the TLR-4 signalling pathway are activated after acute stress exposure in rat brain frontal cortex and its role in the regulation of the stress-induced neuroinflammatory response, by means of its pharmacological modulation with the intravenous administration of the TLR-4 specific inhibitor TAK-242. Considering that TLR-4 responds predominantly to lipopolysaccharide from gram-negative bacteria, we checked whether increased intestinal permeability and a resultant bacterial translocation is a potential regulatory mechanism of stress-induced TLR-4 activation. RESULTS: Acute restraint stress exposure upregulates TLR-4 expression both at the mRNA and protein level. Stress-induced TLR-4 upregulation is prevented by the protocol of antibiotic intestinal decontamination made to reduce indigenous gastrointestinal microflora, suggesting a role for bacterial translocation on TLR-4 signalling pathway activation. TAK-242 pre-stress administration prevents the accumulation of potentially deleterious inflammatory and oxidative/nitrosative mediators in the brain frontal cortex of rats. CONCLUSIONS: The use of TAK-242 or other TLR-4 signalling pathway inhibitory compounds could be considered as a potential therapeutic adjuvant strategy to constrain the inflammatory process taking place after stress exposure and in stress-related neuropsychiatric diseases.


Assuntos
Translocação Bacteriana/fisiologia , Encefalite/tratamento farmacológico , Lobo Frontal/patologia , Transdução de Sinais/fisiologia , Sulfonamidas/uso terapêutico , Receptor 4 Toll-Like/metabolismo , Animais , Translocação Bacteriana/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Encefalite/etiologia , Imunidade Inata/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Lipopolissacarídeos , Masculino , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Estresse Psicológico/induzido quimicamente , Estresse Psicológico/complicações , Receptor 4 Toll-Like/genética , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo
2.
J Antimicrob Chemother ; 68(10): 2291-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23674766

RESUMO

OBJECTIVES: To explore serum and tissue pharmacodynamics of linezolid versus vancomycin against methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates with different MBC/MIC ratios. METHODS: Five strains (vancomycin MIC/MBCs, mg/L) were used: TOL-1 (2/≥64), TOL-2 (1/16), LT-1 and LT-2 (1/8) and NT (1/2). The linezolid MIC/MBC for all strains was 2/≥64 mg/L. A two-compartment dynamic computerized device was used (inocula 10(7) cfu/mL). Free concentrations obtained in serum and interstitial fluid with twice-daily regimens of 1 g of vancomycin or 600 mg of linezolid were simulated over 48 h. ABBCs (differences between control growth curves and killing curves of bacteria exposed to antibiotics; log10 cfu × h/mL) and log10 reductions in initial inocula were calculated. RESULTS: In serum simulations, vancomycin (AUC0-24/MIC = 251.8 for TOL-1 and 503.6 for the remaining strains) was bacteriostatic against strains with MBC/MIC ≥8, but bactericidal against NT. In interstitial fluid simulations (AUC0-24/MIC = 54.6 for TOL-1 and 109.2 for the remaining strains), initial inocula grew in all cases. Linezolid, both in serum (AUC0-24/MIC = 87.0) and in interstitial fluid (AUC0-24/MIC = 130.6) simulations, reduced initial inocula ≥2.2 log10 for all strains (apart from LT-1 in serum simulations that showed a bacteriostatic profile). ABBCs were similar in serum and interstitial fluid with linezolid, but significantly lower in interstitial fluid simulations with vancomycin. CONCLUSIONS: From the pharmacodynamic perspective (serum concentrations), vancomycin tolerance should include MBC/MIC ≥8 since strains exhibiting this ratio showed bacteriostatic profiles similar to those obtained with isolates with MBC/MIC ratios of 16 or 32. Insufficient concentrations of vancomycin at the simulated infected site were linked to bacteriological failure. Free concentrations of linezolid at the infection site pharmacodynamically covered MRSA.


Assuntos
Acetamidas/farmacologia , Antibacterianos/farmacologia , Líquido Extracelular/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Oxazolidinonas/farmacologia , Soro/química , Vancomicina/farmacologia , Acetamidas/farmacocinética , Antibacterianos/farmacocinética , Diabetes Mellitus , Humanos , Linezolida , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Modelos Teóricos , Oxazolidinonas/farmacocinética , Vancomicina/farmacocinética
3.
Infect Control Hosp Epidemiol ; 44(3): 517-519, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34933701

RESUMO

Triclosan 0.5% by scrubbing does not meet the UNE-EN12791 criteria to be used in the surgical hand preparation (SHP). Triclosan 0.5% by scrubbing followed by ethanol 70% hand rubbing is suitable without the additional characteristic of sustained effect. This limited effectiveness implies that triclosan should be avoided in SHP given the restrictions on its use in consumer antiseptic products. The trial was registered at ClinicalTrials.gov (ID: NCT04538365).


Assuntos
Anti-Infecciosos Locais , Triclosan , Humanos , Triclosan/farmacologia , Carga Bacteriana , Desinfecção das Mãos , Anti-Infecciosos Locais/farmacologia , Antissepsia
4.
Infect Control Hosp Epidemiol ; 42(11): 1382-1384, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33478620

RESUMO

A crossover trial was conducted to compare hand rub and hand scrub-brush methods for reducing bacterial loads when using propan-1-ol-60% according to European regulations. Both methods significantly reduced the bacterial load immediately after antisepsis, but only the hand rub method achieved significant bacterial load reduction 3 hours after the procedure.


Assuntos
Anti-Infecciosos Locais , Antissepsia , Carga Bacteriana , Estudos Cross-Over , Mãos , Desinfecção das Mãos , Humanos
5.
Rev Esp Quimioter ; 22(4): 224-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20082045

RESUMO

The aim of the study was to explore the structure and growth dynamics of Staphylococcus aureus resistant to methicillin (MRSA) colonies using semithin sections visualized by light microscope. One S. aureus susceptible to methicillin (MSSA) and one MRSA clinical strains were studied. Colonies in agar plates were embedded in epoxy resin after each incubation period (24 h and 48 h) at 37 degrees . Semithin sections of 0.5 µm were stained with toluidine blue and visualized by light microscope. Microscopically, no structural differences were observed between SASM and SARM colonies but differences were observed in both strains between 24 and 48 h incubation periods. Colonies showed two layers clearly differentiated at 24 h independently of the resistance to methicillin: (A) one basal layer with high density of population in contact with culture media, and (B) one superficial layer with a lower density of population. Colonies showed four layers at 48 h: (A) one basal layer with high density of population; (B) one clear layer constituted by very degraded bacterial remains in which can be observed cocci dispersed with their dyeing properties; (C) one mixed layer constituted by viable bacteria and little degraded bacterial remains (D) one superficial layer with a lower density of population than basal layer. Colonial architecture is a complex and time-dependent process.


Assuntos
Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Antibacterianos/farmacologia , Meios de Cultura
6.
Artigo em Inglês | MEDLINE | ID: mdl-29468052

RESUMO

Background: This study aimed to estimate the prevalence of methicillin-susceptible and -resistant Staphylococcus aureus (MSSA and MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE) nasopharyngeal carriage among Doctors of Podiatric Medicine (Podiatrists) and to determine the potential risk factors. Methods: A cross-sectional study was carried out in 2016-2017 among 239 podiatrists in Spain. The presence of MSSA, MRSA, and MRSE was determined by microbiological analysis of nasal exudate and antimicrobial susceptibility was determined. Each podiatrist completed a questionnaire. The questionnaire comprised various parameters such as sex, age, podiatry experience duration, underlying diseases, prior antibiotic treatment, hospitalization during the last year, and use of a protective mask, an aspiration system, or gloves. Results: The prevalence of MSSA, MRSA, and MRSE was 23.0%, 1.3%, and 23.8%, respectively. The MSSA prevalence was higher among podiatrists who did not use an aspiration system (32.3%) compared to those who did (19.3%; p = 0.0305), and among podiatrists with respiratory diseases (36.8%) compared to those without (20.8%; p = 0.0272). The MRSE prevalence was higher among men (33.7%) compared to women (8.6%; p = 0.0089), podiatrists aged ≥50 (38.5%) compared to ≤35 (17.8%; p = 0.0101), and podiatrists with ≥15 (39.3%) compared to ≤5 years of podiatry experience (12.5%; p = 0.0015). Among the S. aureus strains, 84.5% were resistant to penicillin, 22.4% to erythromycin, 20.7% to clindamycin, and 12.7% to mupirocin. The MRSE strains were resistant to penicillin (93.0%), erythromycin (78.9%), and mupirocin (73.7%). Conclusions: The prevalence of S. aureus and S. epidermidis nasal carriage is low among Spanish podiatrists compared to other health professionals.


Assuntos
Antibacterianos/farmacologia , Nariz/microbiologia , Staphylococcus/efeitos dos fármacos , Staphylococcus/crescimento & desenvolvimento , Adulto , Fatores Etários , Estudos Transversais , Feminino , Humanos , Masculino , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Sexuais , Espanha/epidemiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/crescimento & desenvolvimento , Inquéritos e Questionários
7.
Neuropharmacology ; 103: 122-33, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26686392

RESUMO

Recent studies have suggested that depression is accompanied by an increased intestinal permeability which would be related to the inflammatory pathophysiology of the disease. This study aimed to evaluate whether experimental depression presents with bacterial translocation that in turn can lead to the TLR-4 in the brain affecting the mitogen-activated protein kinases (MAPK) and antioxidant pathways. Male Wistar rats were exposed to chronic mild stress (CMS) and the intestinal integrity, presence of bacteria in tissues and plasma lipopolysaccharide levels were analyzed. We also studied the expression in the prefrontal cortex of activated forms of MAPK and some of their activation controllers and the effects of CMS on the antioxidant Nrf2 pathway. Our results indicate that after exposure to a CMS protocol there is increased intestinal permeability and bacterial translocation. CMS also increases the expression of the activated form of the MAPK p38 while decreasing the expression of the antioxidant transcription factor Nrf2. The actions of antibiotic administration to prevent bacterial translocation on elements of the MAPK and Nrf2 pathways indicate that the translocated bacteria are playing a role in these effects. In effect, our results propose a role of the translocated bacteria in the pathophysiology of depression through the p38 MAPK pathway which could aggravate the neuroinflammation and the oxidative/nitrosative damage present in this pathology. Moreover, our results reveal that the antioxidant factor Nrf2 and its activators may be involved in the consequences of the CMS on the brain.


Assuntos
Translocação Bacteriana , Transtorno Depressivo/metabolismo , Transtorno Depressivo/microbiologia , Encefalite/metabolismo , Encefalite/microbiologia , Microbiota , Transdução de Sinais , Animais , Antibacterianos/administração & dosagem , Translocação Bacteriana/efeitos dos fármacos , Lipopolissacarídeos/sangue , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Estresse Psicológico , Proteínas de Junções Íntimas/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
8.
Int J Antimicrob Agents ; 24(1): 79-82, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15225866

RESUMO

The in vitro effect that the presence of components of non-specific immunity (serum plus polymorphonuclear neutrophils) has on the bactericidal activity of co-amoxiclav was explored against Streptococcus pneumoniae strains exhibiting an amoxicillin MIC > or =4 mg/L. Eight penicillin-resistant clinical isolates non-susceptible to co-amoxiclav with MICs of 4 (two strains), 8 (four strains) and 16 mg/L (two strains) were used. Values of MBC were identical to MIC values in all cases. Time-kill curves were performed with co-amoxiclav concentrations achievable in serum after a single oral dose administration of the new 2000/125 mg sustained-release formulation. Results were expressed as percentage of reduction of initial inocula after 3 h incubation. Control curves showed growth with no reduction of initial inocula. Against strains with MIC of 4 and 8 mg/L, the results obtained with the antibiotic alone or with the presence of factors of non-specific immunity were similar, with a weak combined effect due to the intrinsic activity of co-amoxiclav (reductions of initial inocula ranging from 70 to 99.16%). Against strains with MIC of 16 mg/L, the addition of PMN in the presence of serum increased the reduction of bacterial load provided by the aminopenicillin, even at sub-inhibitory concentrations (25.8% versus 51.1% at 0.5 x MIC concentration--8/0.5 mg/L). This combined activity against strains with an amoxicillin MIC of 16 mg/L which decreased the bacterial load may be important in preventing bacterial proliferation within the host and the transmission of resistant clones to others.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Amoxicilina/farmacologia , Quimioterapia Combinada/farmacologia , Neutrófilos/imunologia , Streptococcus pneumoniae/efeitos dos fármacos , Administração Oral , Combinação Amoxicilina e Clavulanato de Potássio/administração & dosagem , Combinação Amoxicilina e Clavulanato de Potássio/sangue , Quimioterapia Combinada/administração & dosagem , Quimioterapia Combinada/sangue , Humanos , Testes de Sensibilidade Microbiana
9.
Rev. int. cienc. podol. (Internet) ; 13(2): 131-135, 2019. graf, tab
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-186923

RESUMO

Con la adaptación al EEES (Espacio Europeo de Educación Superior), se ha comenzado a impartir Microbiología dentro de la materia de Biopatología, introduciendo como actividad docente los créditos prácticos de Microbiología para conseguir mejorar las competencias que deberán adquirir los estudiantes como parte de su formación integral. Se compararon los resultados de la evaluación de 34 alumnos del curso 2011-2012, analizando los resultados entre la pregunta de integración teórico-práctica (TP)y la que únicamente se había explicado en la clase teórica (T).Se encontraron diferencias significativas (p<0,001) entre la nota media que presentaron los alumnos que habían superado la asignatura y los que no la habían superado para la prueba T, mientras que estas medias no fueron estadísticamente significativas para la prueba TP .Podemos concluir que el aprendizaje evaluado en la pregunta TP ha sido satisfactorio en los dos grupos, incluso los alumnos que no han superado la asignatura han logrado alcanzar buenos resultados en esta prueba


With the adaptation to the EHEA (European Higher Education Area ), Microbiology has begun to be taught within the field of Biopathology, introducing as a teaching activity the practical credits of Microbiology in order to improve the skills that students should acquire as part of their integral training. The results of the evaluation of 34 students of the 2011-2012 academic year were compared, analyzing the results between the question of theoretical-practical integration (TP) and the one that had only been explained in the theoretical class (T). Significant differences were found ( p <0.001) between the average score of the students who had passed the course and those who had not passed it for the T test, while these means were not statistically significant for the TP test. We can conclude that the learning evaluated in the question TP has been satisfactory in both groups, even students who have not passed the course have achieved good results in this test


Assuntos
Humanos , Ensino , Microbiologia/educação , Podiatria/educação , Microbiota , Credenciamento/normas
10.
Rev. int. cienc. podol. (Internet) ; 13(2): 55-60, 2019. tab, graf
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-186916

RESUMO

Se ha planteado como objetivo la mejora de la calidad de la docencia de la Microbiología mediante la actualización de la metodología docente , introduciendo como actividad docente el aprendizaje activo basado en preguntas (inquiry-based learning:IBL) para conseguir mejorar las competencias que deberán adquirir los estudiantes como parte de su formación integral. En este estudio han participado 63 alumnos de Segundo Curso del Grado de Podología de la Universidad Complutense de Madrid (Curso 2017-2018), y se ha calculado el porcentaje de alumnos que participaron en las 4 pruebas (4IBL), 3 pruebas (3 IBL), en 2 (2 IBL), en 1 (1 IBL), y los que no participaron en ninguna y posteriormente se relacionó con las calificaciones obtenidas en la asignatura de Microbiología. Se incluyeron las preguntas IBL que se realizaron en clase en el campus virtual de la asignatura, pero incluyendo la corrección de las mismas.En los alumnos que realizaron alguna prueba IBL se obtuvieron calificaciones mejores que en aquellos que no habían participado en ninguna. Consideramos que el uso del campus virtual unido a la actualización en la metodología docente puede mejorar el rendimiento académico de los estudiantes de Microbiología


Our focus here is to improve teaching methods in University microbiology classes and the development of educational practices that explicit engage students while enhacing how they learn Microbiology. These practices including inquiry-based learning (IBL) in which students are actively engaged in the learning process for improving the skills to be acquired as part of their effective learning . This study included 63 Microbiology students of Second Year Degree in Podiatry at the Complutense University (Academic Year 2017-2018), and calculated the percentage of students who used these resources 4 IBL, 3 IBL , 2IBL , 1IBL , and that did not participate in any and ubsequently related to the student performance in the Microbiology exam . The IBL questions that were done in class ,were included in the virtual campus , including the correction .Students who prepared IBL scored higher en exam questions , findings also indicate that this activity can measure learning and improve exam preparation. We believe that the benefits of active learning methods with virtual campus over lecture instruction are consistent and can increases student performance in Microbiology


Assuntos
Humanos , Podiatria/educação , Microbiologia/educação , Estudantes/estatística & dados numéricos , 50054 , Aprendizagem , Desempenho Acadêmico
12.
Arch Oral Biol ; 58(11): 1584-93, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24112723

RESUMO

OBJECTIVE: Streptococcus oralis is an early coloniser of the oral cavity that contributes to dental plaque formation. Many different genotypes can coexist in the same individual and cause opportunistic infections such as bacterial endocarditis. However, little is known about virulence factors involved in those processes. The aim was to analyze the evolving growth of S. oralis colony/biofilm to find out potentially pathogenic features. DESIGN: Thirty-three S. oralis isolates were analyzed for: (1) biofilm production, by spectrophotometric microtiter plate assay; (2) colonial internal architecture, by histological methods and light and electron microscopy; (3) agar invasion, by a new colony-biofilm assay. RESULTS: S. oralis colonies showed two different growth patterns: (1) fast growth rate without invasion or minimally invasive; (2) slow growth rate, but high invasion ability. 12.1% of strains were biofilm non-producers and 24.2% not invasive, compared to 51.5% biofilm high-producers and 39.4% very invasive. Both phenotypic characteristics tended to be mutually exclusive. However, a limited number of strains (15%) co-expressed these features at the highest level. CONCLUSIONS: Morphological plasticity of S. oralis highlighted in this study may have important ecological and clinical implications. Coexistence of strains with different growth patterns could produce a synergic effect in the formation and development of subgingival dental plaque. Moreover, invasiveness might regulate dissemination and colonisation mechanisms. Simultaneous co-expression of high-invasive and high-biofilm phenotypes gives a fitness advantage during colonisation and may confer higher pathogenic potential.


Assuntos
Biofilmes/crescimento & desenvolvimento , Placa Dentária/microbiologia , Boca/microbiologia , Streptococcus oralis/crescimento & desenvolvimento , Fatores de Virulência , Técnicas Bacteriológicas , Humanos , Espectrofotometria , Streptococcus oralis/citologia , Streptococcus oralis/patogenicidade
13.
Rev Esp Quimioter ; 26(3): 214-9, 2013 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-24080887

RESUMO

OBJECTIVES: The genus Legionella includes very pleomorphic species responsible for disease outbreaks in humans. The appearance of such has great importance to develop artificial biofilms in aquatic ecosystems. The aim of this work was to study the dynamics of growth and evolution of the internal structure of colonies of representative species of the genus as static biofilm model. METHODS: Isolated colonies of Legionella pneumophila and Legionella bozemanii grown in specific media for three and fifteen days were processed for histological methods and embedded in paraffin and epoxy resin for analysis by light microscopy, electron microscopy and image analysis. RESULTS. In colonies of both species were observed and defined specific architectural patterns, based on stratification and evolve over time. The strata differ in the amount of extracellular matrix, the morphology and population density and the proportion of dead cells. The internal structure of three days colonies showed large differences between L. pneumophila (two layers) and L. bozemanii (four layers). However, in the fifteen days colonies of both species evolved towards a common unique pattern formed by three layers. In both species the growth was also found within the culture medium, although this phenomenon was more intense in L. bozemanii with unique, central and larger invasions. CONCLUSIONS: Our results demonstrate that Legionella colonies on solid culture media are a good model of static biofilm with a complex structural dynamics characterized by the presence of morphological and functional subpopulations. We bring here an histological approach model, allowing, in further research, detailed studies in evolutionary adaptations in multicellular communities to adverse media and to antimicrobials in Legionella species of clinical interest.


Assuntos
Biofilmes/crescimento & desenvolvimento , Legionella pneumophila/crescimento & desenvolvimento , Legionella/crescimento & desenvolvimento , Meios de Cultura , Humanos , Processamento de Imagem Assistida por Computador , Legionella/fisiologia , Legionella pneumophila/fisiologia , Doença dos Legionários/microbiologia , Microscopia Eletrônica de Transmissão , Inclusão em Parafina , Inclusão em Plástico , Especificidade da Espécie
14.
Rev Esp Quimioter ; 26(2): 97-102, 2013 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-23817645

RESUMO

The aim of the study was to investigate biofilm formation in Gram negative bacteria and to quantify biofilm production applying a new developed technique that made possible to compare results about biofilm formation within the different Gram negative bacteria species. A total of 153 Gram negative strains corresponding to 12 different bacterium species were studied applying a variation of the optic density measurement technique reported by Stepanovic et al. Data obtained with optic density analysis allow to classify microorganisms in strong biofilm developers, moderate biofilm developers, weak biofilm developers and no biofilm developers. The results were expressed in two ways, using in both cases the same statistical method: without standardization, where controls were different depending on the day optic density measurements were performed, and standardized using a correction factor, using the same control for every strain of all our bacterium species in our study, which allows result homogenization. The obtained results in our study after data analysis and standardization show that over the 153 Gram negative strains in our study, 105 of them were no biofilm developers, representing 63.75% of all the studied bacterium genera. We consider that standardization and quantification of biofilm development in Gram negative bacteria can be useful in clinical practice, because biofilm development ability can lead or focus the gold treatment of pathologies produced by these microorganisms.


Assuntos
Biofilmes/crescimento & desenvolvimento , Bactérias Gram-Negativas/crescimento & desenvolvimento , Carga Bacteriana , Técnicas Bacteriológicas , Densitometria , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Padrões de Referência , Espanha , Especificidade da Espécie
15.
Rev Esp Quimioter ; 26(1): 34-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23546460

RESUMO

OBJECTIVES: The in-depth growth in solid culture media is a common feature in filamentous fungi and yeasts. However, there are very few bacterial species in which this phenomenon has been documented. The aim of this work was to assess the agar invasiveness of a wide range of Gram-positive and Gram-negative bacterial species of clinical interest. MATERIAL AND METHODS: Three different clinical isolates for each of eleven bacterial species were plated onto Columbia blood agar and let grow up to 15 days. Isolated colonies were processed by histological methods, embedded in epoxy resin, and then, semithin sections were stained with toluidine blue and visualized by light microscopy. RESULTS: Growth within the agar was observed in at least one strain in 9 of the 11 studied species. Invasions of Gram-negative rods were small, not plentiful, and round or triangle-shaped. In Gram-positive cocci, invasions were of big size, abundant and of variable shape (lentiform, globular, irregular, arrowhead) depending on the species. CONCLUSIONS: We propose that the growth within the agar can indicate a survival strategy common to many bacterial species, and so far, not previously reported. This strategy could be either a nutrient gradient tropism or the spread and colonization of new ecological niches, with potential implications in pathogeny.


Assuntos
Meios de Cultura , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Ágar , Contagem de Colônia Microbiana , Corantes , Fenótipo , Especificidade da Espécie , Cloreto de Tolônio
16.
J Microbiol Methods ; 94(3): 267-73, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23838131

RESUMO

Invasion of the culture medium is a feature frequently studied in yeasts, in which it has been related to a greater virulence, but it is practically unknown in bacteria. Recently, it has been demonstrated that several clinically relevant bacterial species were also able of invading agar media, so it was necessary to design a microbiological assay to study the expression of this character in bacteria. Accordingly, a bacterial agar invasion test based on colony/biofilm development was designed, which allows qualitative and quantitative characterization of bacterial growth into the agar culture medium. Once the culture conditions were optimized, the test was applied to 90 strains from nine bacterial species, validating its usefulness for differentiating invasive strains (positive) from those non invasive (negative). The test also allows sorting invasive strains according to agar invasion intensity (low, moderate, high) and topographic invasion pattern (peripheral, homogeneous, mixed). Moreover, an image analysis routine to quantify the invasion was developed. Implemented method enables direct measuring of two invasion parameters (invasion area and number of invasion dots), automated calculation of three relative variables (invasion relative area, invasion dots relative density, and invasion dot average area), and the establishment of strain specific frequency histograms. This new methodology is simple, fast, reproducible, objective, inexpensive and can be used to study a great number of specimens simultaneously, all of which make it suitable for incorporation to the routine of any microbiology laboratory. It could also be a useful tool for additional studies related to clinical aspects of bacterial isolates such as virulence and antimicrobial response.


Assuntos
Ágar/metabolismo , Bactérias , Técnicas Bacteriológicas/métodos , Biofilmes , Bactérias/citologia , Bactérias/crescimento & desenvolvimento , Bactérias/patogenicidade , Fenômenos Fisiológicos Bacterianos , Meios de Cultura/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Microscopia/métodos , Virulência/fisiologia
17.
Histol Histopathol ; 28(10): 1351-60, 2013 10.
Artigo em Inglês | MEDLINE | ID: mdl-23645570

RESUMO

Bacillus subtilis has been used as a classic model to study biofilm formation and sporulation process. Colonies of wild-type strains usually have a complex external morphology, but the details of their internal architecture are still undisclosed. Since bacterial biofilms fulfill the criteria to be considered tissues, the aim of this work was to analyse B. subtilis colony-biofilm internal architecture evolution and sporulation dynamics using histological techniques. Transversal sections of colony-biofilms incubated from 24 hours up to 20 days were stained using histochemical techniques to analyse the internal structure by light and electron microscopy. A morphometric study of the different structural biofilm components was performed by image analysis, and an application to quantify spores was developed. Internal biofilm architecture was characterised by a stratified pattern, which evolved from 3 strata at 24 hours, up to 5 strata at 20 days. At 48 hours, strata at the central area of the biofilm was folded, resulting in elevated structures (vein-like structures) that could reach up to 465 µm in height. Sporulation started at 48 hours, at the top of the vein-like structures, at the interface between the two uppermost strata. At 20 days spores formed a continuous central layer, representing 7.5% of the total biofilm. In summary, our results demonstrate that B. subtilis colony-biofilm has a complex and organized internal architecture, evolving over time, and taking place in different cell subpopulations with different functionalities. Furthermore, in situ spore quantification described in this work could be a good alternative to the classical chamber counting.


Assuntos
Bacillus subtilis/metabolismo , Bacillus subtilis/fisiologia , Biofilmes , Esporos Bacterianos/fisiologia , Animais , Aderência Bacteriana , Escherichia coli/metabolismo , Microscopia , Microscopia Eletrônica , Modelos Estatísticos , Staphylococcus aureus/metabolismo , Fatores de Tempo
18.
Rev Esp Quimioter ; 25(4): 269-73, 2012 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-23303259

RESUMO

INTRODUCTION: In cystic fibrosis, the Pseudomonas aeruginosa cells grow inside the thick mucus layer. In spite of being an obligate aerobe, P. aeruginosa is able to grow in a limited oxygen environment. Bacterial cells could be suddenly exposed to high oxygen levels due to the movements of the mucus mass. The aim of study was to determine the impact of a previous anaerobic incubation on the antimicrobial susceptibility of P. aeruginosa strains isolated from patients with cystic fibrosis. MATERIALS AND METHODS: Four P. aeruginosa strains were used in this study (ATCC 23389 and 3 clinical isolates). The disk diffusion method was used to determine the antimicrobial susceptibility. RESULTS: The anaerobic pre-incubation produced changes on the susceptibility in all studied strains. All susceptible strains after an aerobic incubation remained susceptible after an anaerobic incubation except one clinical strain, which became resistant to betalactams. The response was strain-dependent and the most significant increase in susceptibility was observed in two of the three clinical isolates when ciprofloxacin was used. CONCLUSIONS: The antimicrobial susceptibility of P. aeruginosa strains varies after their exposure to anaerobic conditions. Treatments promoting mucus fluidization could contribute to increase the antimicrobial efficacy.


Assuntos
Fibrose Cística/complicações , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana/fisiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Aerobiose , Anaerobiose , Antibacterianos/farmacologia , Expectorantes/farmacologia , Humanos , Viabilidade Microbiana , Muco/microbiologia , Oxigênio/metabolismo , Infecções por Pseudomonas/complicações , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/metabolismo , Sistema Respiratório/microbiologia
19.
Rev. esp. quimioter ; 30(1): 34-39, feb. 2017. tab
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-159557

RESUMO

Objetivo. Valorar si existe una diferencia significativa en tasa de infección tras cirugía de extracción dentaria en dos hospitales de Noruega y España, donde se aplican protocolos de profilaxis quirúrgica diferentes. Material y Métodos. Se realizó un estudio observacional analítico, tipo cohortes retrospectivo, analizando pacientes sanos, sin factores de riesgo, operados de tercer molar incluido en los servicios de maxilofacial de dos hospitales diferentes: St. Olav de Trondheim (Noruega) y Clínico San Carlos de Madrid (España). Se recogieron las variables: edad, número de piezas extraídas, tipo de anestesia, y observaciones recogidas en la historia clínica sobre el curso de la operación. Para valorar el desarrollo infección postoperatoria se recogieron los datos de los pacientes que escogieron el hospital como lugar de retirada de los puntos en el Hospital St. Olav, y en el Hospital Clínico San Carlos se llevó a cabo una encuesta telefónica para conocer el curso de la operación meses después. Resultados. El 11,1% de los pacientes operados en el Hospital St. Olav recibió pauta antibiótica durante una semana tras la operación, mientras que en el Hospital Clínico San Carlos fue del 100%. La tasa de infección tras ésta fue del 15% en el Hospital de St. Olav y del 7,5% en el Hospital Clínico siendo estas diferencias no estadísticamente significativas. Conclusiones. La administración sistemática de antibiótico a pacientes sanos sin factores de riesgo sometidos a extracción quirúrgica del tercer molar retenido es una práctica rutinaria en clínica que no parece estar justificada (AU)


Objective. To assess whether there is a significant difference in infection rate after surgery tooth extraction in two different hospitals from Norway and Spain where different surgical antimicrobial prophylaxis protocols are applied. Methods. An analytical observational study was conducted, retrospective cohorts type, analyzing healthy patients with no risk factors, who were third molar tooth operated in maxillofacial services of two different hospitals: St. Olav in Trondheim (Norway) and Clínico San Carlos in Madrid (Spain). The collected variables were: age, number of tooth removed, anesthesia type, and observations about the course of the operation registered in the clinical history. To assess the development of postoperative infection, patient’s data of those who chose the hospital as the place to remove the suture thread were collected in Norway, whereas in Spain a telephone survey was conducted to determine the course of the operation months later. Results. In St. Olav Hospital 11.1% of patients operated received antibiotic regimen after surgery, while in Hospital San Carlos were 100%. The infection rate was 15% in St.Olav Hospital and 7.5% in Hospital San Carlos. These differences were no statistically significant. Conclusions. The routine administration of antibiotics to healthy patients with no risk factors undergoing impacted third molar surgical removal is a common clinical practice which it does not seem to be justified (AU)


Assuntos
Humanos , Masculino , Feminino , Padrões de Prática Odontológica/normas , Prescrições de Medicamentos/normas , Dente Impactado/tratamento farmacológico , Dente Impactado/prevenção & controle , Profilaxia Dentária/métodos , Dente Serotino , Dente Serotino/cirurgia , Estudos Retrospectivos , Estudos de Coortes
20.
Rev. int. cienc. podol. (Internet) ; 10(2): 85-94, 2016. tab, graf
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-151224

RESUMO

Se ha planteado como objetivo la mejora de la calidad de la docencia de la Microbiología mediante la actualización de la metodología docente, introduciendo como actividad docente el aprendizaje activo basado en preguntas (inquirybased learning:IBL) para conseguir mejorar las competencias que deberán adquirir los estudiantes como parte de su formación integral. En este estudio han participado 55 alumnos de Segundo Curso del Grado de Podología (Curso 2014-2015), y se ha calculado el porcentaje de alumnos que participaron en las 3 pruebas (3 IBL), en 2 (2 IBL), en 1 (1 IBL), y los que no participaron en ninguna y posteriormente se relacionó con las calificaciones obtenidas en la asignatura de Microbiología. Se incluyeron las preguntas IBL que se realizaron en clase en el campus virtual de la asignatura, pero sin incluir la corrección de las mismas. En los alumnos que realizaron alguna prueba IBL se obtuvieron calificaciones mejores en las preguntas diseñadas para analizar la síntesis de conocimientos y el análisis de datos que en aquellos que no habían participado en ninguna. Al finalizar la actividad se realizó un estudio transversal a través de un cuestionario autocumplimentado en el que se valoraba la opinión de los alumnos sobre el aprendizaje activo mediante IBL valorando positivamente esta actividad para medir el aprendizaje y mejorar la preparación del examen. Consideramos que el uso del campus virtual unido a la actualización en la metodología docente puede mejorar el rendimiento académico de los estudiantes de Microbiología (AU)


Our focus here is to improve teaching methods in University microbiology classes and the development of educational practices that explicit engage students while enhacing how they learn Microbiology. These practices including inquiry-based learning (IBL) in which students are actively engaged in the learning process for improving the skills to be acquired as part of their effective learning . This study included 55 Microbiology students of Second Year Degree in Podiatry (Academic Year 2014-2015), and calculated the percentage of students who used these resources 3 IBL, 2IBL, 1IBL, and that did not participate in any and subsequently related to the student performance in Microbiology exam. The IBL questions that were done in class ,were included in the virtual campus , but not including the correction. Students who prepared IBL scored higher en exam questions designed to test synthesis of knowledge and analysis of data. In order to assess the perceived impact of the active learning, the students were asked to fill out a questionnaire evaluating IBL positively considering that this activity can measure learning and improve exam preparation. We believe that the benefits of active learning methods over lecture instruction are consistent and can increases student performance in Microbiology (AU)


Assuntos
Humanos , Podiatria/educação , Microbiologia/educação , Currículo , Avaliação Educacional , Interface Usuário-Computador
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