Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.251
Filtrar
1.
Methods Mol Biol ; 2278: 117-129, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33649952

RESUMO

Bifidobacteria are able to utilize a diverse range of host-derived and dietary carbohydrates, the latter of which include many plant-derived oligo- and polysaccharides. Different bifidobacterial strains may possess different carbohydrate utilization abilities. These metabolic abilities can be studied using classical bacterial growth assessment methods, such as measurement of changes in optical density or acidity of the culture in the presence of the particular carbohydrate to generate growth and acidification curves, respectively. Scientists may also be interested in the growth rate during the exponential growth phase, and the maximum OD that is reached on a particular sugar, or the length of the lag phase. Furthermore, high-performance liquid chromatography (HPLC) and high-performance anion exchange chromatography coupled to pulsed amperometric detection (HPAEC-PAD) are extensively used in carbohydrate and metabolic end-product analysis due to their versatility and separation capabilities.


Assuntos
Bifidobacterium/metabolismo , Metabolismo dos Carboidratos , Bifidobacterium/crescimento & desenvolvimento , Técnicas de Cultura de Células/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , Contagem de Colônia Microbiana/métodos
2.
Methods Mol Biol ; 2220: 3-16, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32975762

RESUMO

Conventional methods for the detection of Listeria monocytogenes in foods and environmental samples rely on selective pre-enrichment, enrichment, and plating. This is followed by confirmation of suspected colonies by testing a limited number of biochemical markers.


Assuntos
Listeria monocytogenes/isolamento & purificação , Contagem de Colônia Microbiana/métodos , Meios de Cultura/química , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Humanos , Listeriose/microbiologia
3.
Methods Mol Biol ; 2220: 189-200, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32975776

RESUMO

Listeria monocytogenes is a model intracellular pathogen that can invade the cytoplasm of host mammalian cells. Cellular invasion can be measured using standard techniques, such as the classical gentamicin protection assay, based on the quantification of colony-forming units from lysates of infected cells. In addition, there are methods based on immunofluorescence microscopy which allow for assaying invasion in a medium- to high-throughput manner. In the following sections, we detail two different assays that can be used alone or in combination to quantify the internalization of L. monocytogenes in host cells.


Assuntos
Listeria monocytogenes/fisiologia , Listeriose/patologia , Carga Bacteriana/métodos , Contagem de Colônia Microbiana/métodos , Células HeLa , Interações Hospedeiro-Patógeno , Humanos , Listeriose/microbiologia , Coloração e Rotulagem/métodos
4.
PLoS One ; 15(12): e0238901, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33338037

RESUMO

Despite the recent increase in interest in indoor air quality regarding mould, there is no universally accepted standard media for the detection of airborne fungi, nor verification of many commonly used techniques. Commonly used media including malt-extract agar (MEA), Sabouraud dextrose agar (Sab), potato dextrose agar (PDA) with and without antibiotics chloramphenicol & gentamycin (CG) were compared for their suitability in detecting a range of airborne fungi by collecting 150 L outdoor air on a number of different days and seasons via an Anderson 400-hole sampler in suburban Melbourne, Australia. There was relatively little variation in mean numbers of colony forming units (CFU) and types of fungi recovered between MEA, PDA, Sab media groups relative to variation within each group. There was a significant difference between Sab, Dichloran-18% glycerol (DG18) and V8® Original juice agar media, however. Antibiotics reliably prevented the growth of bacteria that typically interfered with the growth and appearance of fungal colonies. There was no significant evidence for a growth enhancing factor from potato, mineral supplements or various vegetable juices. Differing glucose concentrations had modest effects, showing a vague ideal at 2%-4% with peptone. Sanitisation of the aluminium Andersen 400-hole sampler top-plate by flame is possible, but not strictly required nor advisable. The use of SabCG as a standard medium was generally supported.


Assuntos
Fungos/crescimento & desenvolvimento , Ágar/metabolismo , Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/análise , Austrália , Contagem de Colônia Microbiana/métodos , Meios de Cultura/metabolismo , Monitoramento Ambiental/métodos , Estações do Ano
5.
Cochrane Database Syst Rev ; 10: CD013686, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-33047816

RESUMO

BACKGROUND: Many dental procedures produce aerosols (droplets, droplet nuclei and splatter) that harbour various pathogenic micro-organisms and may pose a risk for the spread of infections between dentist and patient. The COVID-19 pandemic has led to greater concern about this risk. OBJECTIVES: To assess the effectiveness of methods used during dental treatment procedures to minimize aerosol production and reduce or neutralize contamination in aerosols. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases on 17 September 2020: Cochrane Oral Health's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (in the Cochrane Library, 2020, Issue 8), MEDLINE Ovid (from 1946); Embase Ovid (from 1980); the WHO COVID-19 Global literature on coronavirus disease; the US National Institutes of Health Trials Registry (ClinicalTrials.gov); and the Cochrane COVID-19 Study Register. We placed no restrictions on the language or date of publication. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and controlled clinical trials (CCTs) on aerosol-generating procedures (AGPs) performed by dental healthcare providers that evaluated methods to reduce contaminated aerosols in dental clinics (excluding preprocedural mouthrinses). The primary outcomes were incidence of infection in dental staff or patients, and reduction in volume and level of contaminated aerosols in the operative environment. The secondary outcomes were cost, accessibility and feasibility. DATA COLLECTION AND ANALYSIS: Two review authors screened search results, extracted data from the included studies, assessed the risk of bias in the studies, and judged the certainty of the available evidence. We used mean differences (MDs) and 95% confidence intervals (CIs) as the effect estimate for continuous outcomes, and random-effects meta-analysis to combine data. We assessed heterogeneity. MAIN RESULTS: We included 16 studies with 425 participants aged 5 to 69 years. Eight studies had high risk of bias; eight had unclear risk of bias. No studies measured infection. All studies measured bacterial contamination using the surrogate outcome of colony-forming units (CFU). Two studies measured contamination per volume of air sampled at different distances from the patient's mouth, and 14 studies sampled particles on agar plates at specific distances from the patient's mouth. The results presented below should be interpreted with caution as the evidence is very low certainty due to heterogeneity, risk of bias, small sample sizes and wide confidence intervals. Moreover, we do not know the 'minimal clinically important difference' in CFU. High-volume evacuator Use of a high-volume evacuator (HVE) may reduce bacterial contamination in aerosols less than one foot (~ 30 cm) from a patient's mouth (MD -47.41, 95% CI -92.76 to -2.06; 3 RCTs, 122 participants (two studies had split-mouth design); very high heterogeneity I² = 95%), but not at longer distances (MD -1.00, -2.56 to 0.56; 1 RCT, 80 participants). One split-mouth RCT (six participants) found that HVE may not be more effective than conventional dental suction (saliva ejector or low-volume evacuator) at 40 cm (MD CFU -2.30, 95% CI -5.32 to 0.72) or 150 cm (MD -2.20, 95% CI -14.01 to 9.61). Dental isolation combination system One RCT (50 participants) found that there may be no difference in CFU between a combination system (Isolite) and a saliva ejector (low-volume evacuator) during AGPs (MD -0.31, 95% CI -0.82 to 0.20) or after AGPs (MD -0.35, -0.99 to 0.29). However, an 'n of 1' design study showed that the combination system may reduce CFU compared with rubber dam plus HVE (MD -125.20, 95% CI -174.02 to -76.38) or HVE (MD -109.30, 95% CI -153.01 to -65.59). Rubber dam One split-mouth RCT (10 participants) receiving dental treatment, found that there may be a reduction in CFU with rubber dam at one-metre (MD -16.20, 95% CI -19.36 to -13.04) and two-metre distance (MD -11.70, 95% CI -15.82 to -7.58). One RCT of 47 dental students found use of rubber dam may make no difference in CFU at the forehead (MD 0.98, 95% CI -0.73 to 2.70) and occipital region of the operator (MD 0.77, 95% CI -0.46 to 2.00). One split-mouth RCT (21 participants) found that rubber dam plus HVE may reduce CFU more than cotton roll plus HVE on the patient's chest (MD -251.00, 95% CI -267.95 to -234.05) and dental unit light (MD -12.70, 95% CI -12.85 to -12.55). Air cleaning systems One split-mouth CCT (two participants) used a local stand-alone air cleaning system (ACS), which may reduce aerosol contamination during cavity preparation (MD -66.70 CFU, 95% CI -120.15 to -13.25 per cubic metre) or ultrasonic scaling (MD -32.40, 95% CI - 51.55 to -13.25). Another CCT (50 participants) found that laminar flow in the dental clinic combined with a HEPA filter may reduce contamination approximately 76 cm from the floor (MD -483.56 CFU, 95% CI -550.02 to -417.10 per cubic feet per minute per patient) and 20 cm to 30 cm from the patient's mouth (MD -319.14 CFU, 95% CI - 385.60 to -252.68). Disinfectants ‒ antimicrobial coolants Two RCTs evaluated use of antimicrobial coolants during ultrasonic scaling. Compared with distilled water, coolant containing chlorhexidine (CHX), cinnamon extract coolant or povidone iodine may reduce CFU: CHX (MD -124.00, 95% CI -135.78 to -112.22; 20 participants), povidone iodine (MD -656.45, 95% CI -672.74 to -640.16; 40 participants), cinnamon (MD -644.55, 95% CI -668.70 to -620.40; 40 participants). CHX coolant may reduce CFU more than povidone iodine (MD -59.30, 95% CI -64.16 to -54.44; 20 participants), but not more than cinnamon extract (MD -11.90, 95% CI -35.88 to 12.08; 40 participants). AUTHORS' CONCLUSIONS: We found no studies that evaluated disease transmission via aerosols in a dental setting; and no evidence about viral contamination in aerosols. All of the included studies measured bacterial contamination using colony-forming units. There appeared to be some benefit from the interventions evaluated but the available evidence is very low certainty so we are unable to draw reliable conclusions. We did not find any studies on methods such as ventilation, ionization, ozonisation, UV light and fogging. Studies are needed that measure contamination in aerosols, size distribution of aerosols and infection transmission risk for respiratory diseases such as COVID-19 in dental patients and staff.


Assuntos
Microbiologia do Ar , Infecções Bacterianas/prevenção & controle , Controle de Infecções Dentárias/métodos , Doenças Profissionais/prevenção & controle , Viroses/prevenção & controle , Adolescente , Adulto , Aerossóis , Idoso , Filtros de Ar , Criança , Pré-Escolar , Contagem de Colônia Microbiana/métodos , Odontologia , Desinfetantes , Humanos , Controle de Infecções Dentárias/economia , Controle de Infecções Dentárias/instrumentação , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Diques de Borracha , Sucção , Adulto Jovem
6.
Rev. esp. cir. ortop. traumatol. (Ed. impr.) ; 64(5): 318-325, sept.-oct. 2020. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-197610

RESUMO

INTRODUCCIÓN: Las infecciones osteoarticulares representan una complicación mayor en cirugía ortopédica. Se pretende identificar el porcentaje de cánulas de succión colonizadas y determinar la relación entre el tiempo de uso en cirugía y la colonización de estas. MATERIALES Y MÉTODOS: Estudio descriptivo y prospectivo que analiza 546 cánulas de succión utilizadas en cirugía ortopédica limpia en un centro de trauma, entre noviembre del 2017 a marzo del 2018. El extremo distal de la cánula fue cultivado para determinar la proporción de colonización. RESULTADOS: El 7,3% de las cánulas cultivadas tuvieron cultivos positivos para gérmenes patógenos, de los cuales el más frecuente fue Staphylococcus epidermidis con 27,5%. Además, se encontró asociación entre la colonización y el tiempo de uso de la cánula. La posibilidad de colonización de cánulas usadas entre 60 minutos o más, es mayor que en las que se usaron menos de 60 minutos; entre 60 y 90 minutos la posibilidad es dos veces mayor OR= 2,2 (IC:95% 1,1 - 4,1) y en las cánulas usadas por más de 90 minutos es 8 veces mayor OR= 8,49 (IC:95% 1,77 - 40,86). CONCLUSIONES: La proporción de colonización de las cánulas es menor a lo reportado en la literatura. El mayor tiempo de uso de la cánula en la cirugía aumenta el riesgo de la colonización de estas. Se considera realizar estudios de seguimiento para determinar si la colonización de las cánulas de succión se asocia a un incremento de infección postoperatoria


INTRODUCTION: Osteoarticular infections represent a major complication in orthopaedic surgery. The aim is to identify the percentage of suction cannulas colonised and to determine the relationship between the time they are used in surgery and the colonisation of these cannulas. MATERIALS AND METHODS: Descriptive and prospective study that analysed 546 suction cannulas used in clean orthopaedic surgery in a trauma centre, between November 2017 and March 2018. The distal end of the cannula was cultured to determine the colonisation rate. RESULTS: 7.3% of the cultured cannulas were positive for pathogens, the most frequent being Staphylococcus epidermidis at 27.5%. In addition, an association was found between colonisation and the length of time the cannula was used. The possibility of colonisation of cannulas used for between 60minutes or more, is greater than those used for less than 60 minutes; between 60 and 90 minutes the possibility is twice as high OR= 2.2 (CI:95% 1.1 - 4.1) and in cannulas used for more than 90 minutes it is 8 times higher OR= 8.49 (CI:95% 1.77 - 40.86). CONCLUSIONS: The colonisation rate of cannulas is lower than reported in the literature. The longer the cannula is used in surgery increases the risk of their colonisation. Follow-up studies are being considered to determine whether suction cannula colonisation is associated with increased postoperative infection


Assuntos
Humanos , Cânula/microbiologia , Sucção/instrumentação , Procedimentos Ortopédicos/estatística & dados numéricos , Doenças Ósseas Infecciosas/cirurgia , Contagem de Colônia Microbiana/métodos , Infecções Relacionadas a Cateter/microbiologia , Staphylococcus epidermidis/isolamento & purificação , Infecção da Ferida Cirúrgica/microbiologia
7.
PLoS One ; 15(8): e0237069, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32845891

RESUMO

BACKGROUND: Paro and other robot animals can improve wellbeing for older adults and people with dementia, through reducing depression, agitation and medication use. However, nursing and care staff we contacted expressed infection control concerns. Little related research has been published. We assessed (i) how microbiologically contaminated robot animals become during use by older people within a care home and (ii) efficacy of a cleaning procedure. METHODS: This study had two stages. In stage one we assessed microbial load on eight robot animals after interaction with four care home residents, and again following cleaning by a researcher. Robot animals provided a range of shell-types, including fur, soft plastic, and solid plastic. Stage two involved a similar process with two robot animals, but a care staff member conducted cleaning. The cleaning process involved spraying with anti-bacterial product, brushing fur-type shells, followed by vigorous top-to-tail cleaning with anti-bacterial wipes on all shell types. Two samples were taken from each of eight robots in stage one and two robots in stage two (20 samples total). Samples were collected using contact plate stamping and evaluated using aerobic colony count and identification (gram stain, colony morphology, coagulase agglutination). Colony counts were measured by colony forming units per square centimetre (CFU/cm2). RESULTS: Most robots acquired microbial loads well above an acceptable threshold of 2.5 CFU/cm2 following use. The bacteria identified were micrococcus species, coagulase negative staphylococcus, diptheriods, aerobic spore bearers, and staphylococcus aureus, all of which carry risk for human health. For all devices the CFU/cm2 reduced to well within accepted limits following cleaning by both researcher and care staff member. CONCLUSIONS: Companion robots will acquire significant levels of bacteria during normal use. The simple cleaning procedure detailed in this study reduced microbial load to acceptable levels in controlled experiments. Further work is needed in the field and to check the impact on the transmission of viruses.


Assuntos
Desinfecção/métodos , Contaminação de Equipamentos/prevenção & controle , Robótica/tendências , Idoso , Idoso de 80 Anos ou mais , Bactérias , Contagem de Colônia Microbiana/métodos , Infecção Hospitalar/prevenção & controle , Desinfetantes/farmacologia , Humanos , Casas de Saúde , Infecções Estafilocócicas/prevenção & controle
8.
Rev. Asoc. Odontol. Argent ; 108(2): 46-51, mayo-ago. 2020. tab
Artigo em Espanhol | LILACS | ID: biblio-1121108

RESUMO

Objetivos: Comparar ex vivo la eficacia del instrumento XP-endo Finisher y del sistema EndoActivator en la reducción/eliminación del biofilm microbiano en conductos radiculares infectados. Materiales y métodos: Se utilizaron 23 premolares inferiores humanos extraídos cuya longitud fue estandarizada en 17 mm. Todos los conductos se prepararon con el sistema WaveOne Gold Medium (#35.06). Los dientes se esterilizaron, se inocularon con Enterococcus faecalis y se separaron en dos grupos experimentales de 10 piezas cada uno. De los 3 dientes remanentes, 1 fue utilizado como control positivo y 2, como controles negativos. En el grupo 1, las soluciones irrigantes se agitaron con XP-endo Finisher. En el grupo 2, se utilizó EndoActivator. Se tomaron muestras antes de la contaminación, luego de esta y después de la agitación de los irrigantes mediante conos de papel estériles. La carga microbiana fue sembrada en agar sangre y los conos se cultivaron en caldo tripteína de soja. La remoción de la carga microbiana se determinó por la presencia o ausencia de turbiedad del medio. Las unidades formadoras de colonias (UFC) remanentes se cuantificaron y los resultados se categorizaron como R1 (≤10 UFC) o R2 (>10 UFC). Los datos fueron analizados mediante la prueba de Fisher. Resultados: No hubo diferencias significativas entre XP-endo Finisher y EndoActivator (P>0,05). El número de usos no influyó sobre la capacidad operativa de ambos instrumentos (AU)


Aim: To compare ex vivo the effectiveness of the XP-endo Finisher and the EndoActivator in biofilm reduction/ removal from infected root canals. Materials and methods: Twenty three extracted human single-rooted lower premolars were selected and standardised to 17 mm in length. All the canals were prepared with WaveOne Gold Medium reciprocating files (#35.06). The teeth were autoclaved and inoculated with Enterococcus faecalis. The infected teeth were then assigned to 2 experimental groups of 10 teeth each according to the final irrigation/agitation protocol. Of the three remaining teeth, one was used as a positive control, and the other two were used as negative controls. In Group 1 the irrigating solutions were agitated with XP-endo Finisher while in Group 2 the EndoActivator was used. All root canals were sampled before and after contamination, and again after irrigant agitation with sterile paper points. The microbial load was spread on blood agar plates and the paper points were cultured in sterile trypticase soy broth. The removal of the microbial load was determined by visual observation of the turbidity of the media and by quantification of the number of colony-forming units (UFC). The results were categorized as R1 (≤10 UFC) or R2 (>10 UFC). Data were analysed by the Fisher's exact test at P<0.05. Results: No significant differences was found between XP-endo Finisher and EndoActivator (P>0.05) regarding their effectiveness in the reduction/removal of the microbial biofilm. The number of uses of both instruments did not affect their operative performance (AU) Conclusion: XPF and EA were both equally effective for microbial biofilm reduction/removal from ex vivo infected root canals (AU)


Assuntos
Irrigantes do Canal Radicular/química , Equipamentos Odontológicos de Alta Rotação , Biofilmes , Instrumentos Odontológicos , Cavidade Pulpar/microbiologia , Técnicas In Vitro , Contagem de Colônia Microbiana/métodos , Eficácia , Análise Estatística , Enterococcus faecalis/isolamento & purificação , Meios de Cultura
9.
Enferm. glob ; 19(59): 214-227, jul. 2020. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-198889

RESUMO

OBJETIVO: Identificar la colonización por ESKAPES y las características clínicas de los pacientes hospitalizados en una Unidad de Cuidados Intensivos para Adultos de un hospital mixto en Paraná. MÉTODO: Investigación de campo, descriptiva, documental y experimental con enfoque cuantitativo, desarollada en una Unidad de Cuidados Intensivos adultos de un hospital mixto en el suroeste de Paraná, Brasil. La población del estudio consistió en pacientes con ingreso de 48 horas en la Unidad de Cuidados Intensivos, de abril a agosto de 2018 y de abril a agosto de 2019. La muestra totalizó 102 individuos. Para la recopilación de datos clínicos, se utilizó un Checklist y para el análisis microbiológico se recogieron muestras de las cavidades nasales y orales y la secreción traqueal. El análisis de los datos clínicos se produjo a través del software Statistical Package for the Social Sciences. Se realizaron pruebas de frecuencia y chi-cuadrado, teniendo en cuenta la p < 0,05 significativa. RESULTADOS: Se evaluaron un total de 102 pacientes ingresados en la Unidad de Cuidados Intensivos durante el período estudiado. De ellos, 57 (55,8%) fueron colonizados por microorganismos patógenos. En cuanto a la colonización por microorganismos, predominan Staphylococcus aureus (61,4%), seguido de Klebsiella pneumoniae (40,4%), Pseudomonas aeruginosa (26,3%) y Staphylococcus epidermidis (21,1%). Cabe destacar que Klebsiella pneumoniae y Staphylococcus aureus estuvieron presentes en las tres regiones evaluadas. CONCLUSIÓN: El estudio identificó la presencia de colonización en pacientes en estado crítico estudiados, siendo esta colonización, en su mayoría, por bacterias resistentes pertenecientes al grupo ESKAPE


OBJECTIVE: To identify colonization by ESKAPES and clinical characteristics of patients admitted in Adult Intensive Care Unit of a mixed hospital in Paraná. METHOD: Field research, descriptive, documentary and experimental quantitative approach, developed in adult Intensive Care Unit of a mixed hospital in Southwest Paraná, Brazil. The study population consisted of patients with admission from 48 hours in the Intensive Care Unit, from April to August 2018 and April to August 2019. The sample has 102 individuals. For the collection of clinical data, a checklist was used and for microbiological analysis the sample was collected from nasal and oral cavities and tracheal secretion. The analysis of clinical data occurred through the Statistical Package for the Social Sciences software. Descriptive frequency and chi-square test, considering significant p <0,05. RESULTS: A total of 102 patients admitted to the Intensive Care Unit during the period studied were evaluated. On these ones, 57 (55,8%) were colonized by pathogenic microorganisms. Regarding the colonization of microorganisms, there was predominance of Staphylococcus aureus (61,4%), followed by Klebsiella pneumoniae (40,4%), Pseudomonas aeruginosa (26,3%) and Staphylococcus epidermidis (21,1%). It is noteworthy that Klebsiella pneumoniae and Staphylococcus aureus were present in the three regions evaluated. CONCLUSION: The study identified the presence of colonization in critically ill patients studied, being this colonization, mostly, resistant bacteria belonging to the ESKAPE group


OBJETIVO: Identificar a colonização por ESKAPES e características clínicas de pacientes internados em uma Unidade de Terapia Intensiva Adulto de um hospital misto do Paraná. MÉTODO: Pesquisa de campo, descritiva, documental e experimental com abordagem quantitativa, desenvolvida em uma Unidade de Terapia Intensiva adulto de um hospital misto do Sudoeste do Paraná, Brasil. A população do estudo constituiu-se pelos pacientes com admissão a partir de 48 horas na Unidade de Terapia Intensiva, no período de abril a agosto de 2018 e de abril a agosto de 2019. A amostra totalizou 102 indivíduos. Para a coleta de dados clínicos foi utilizado um Checklist e para a análise microbiológica foram coletadas amostras das cavidades nasal e oral e secreção traqueal. A análise dos dados ocorreu por meio do software Statistical Package for the Social Sciences. Realizou-se frequência descritiva e teste de qui-quadrado, considerando significativo p <0,05. RESULTADOS: Foram avaliados 102 pacientes admitidos na Unidade de Terapia Intensiva durante o período pesquisado. Destes, 57 (55,8%) estavam colonizados por microrganismos patogênicos. Em relação à colonização de microrganismos, houve predominância de Staphylococcus aureus (61,4%), seguido por Klebsiella pneumoniae (40,4%), Pseudomonas aeruginosa (26,3%) e Staphylococcus epidermidis (21,1%). Vale ressaltar que, Klebsiella pneumoniae e Staphylococcus aureus estiveram presentes nas três regiões avaliadas. CONCLUSÃO: O estudo identificou a presença de colonização nos pacientes criticamente enfermos pesquisados, sendo essa colonização, em sua maioria, por bactérias resistentes pertencentes ao grupo ESKAPE


Assuntos
Humanos , Contagem de Colônia Microbiana/métodos , Farmacorresistência Bacteriana/imunologia , Acinetobacter baumannii/patogenicidade , Pseudomonas aeruginosa/patogenicidade , Klebsiella pneumoniae/patogenicidade , Enterobacter/patogenicidade , Aprovação de Drogas/organização & administração , Drogas em Investigação/administração & dosagem , Resistência a Múltiplos Medicamentos/imunologia , Infecção Hospitalar/microbiologia , Unidades de Terapia Intensiva/estatística & dados numéricos
10.
PLoS One ; 15(6): e0232869, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579562

RESUMO

Automated colony counting methods have long been known in Microbiology. Numerous methods for automated image analysis have been described and a wide range of commercial products exists. Known advantages are saving cost by reducing enumeration time, automatic documentation, reproducibility, and operator independence. Still, even today the realization of all advantages of automated image analysis makes it necessary to either invest in an expensive, high performance commercial system, or to acquire expert knowledge in image processing. This is a considerable obstacle for many laboratories, and the reason why manual colony counting is still done frequently. This article describes an easy to apply automatic colony counting system-including suggestions for sample preparation-that can be put into operation with basic knowledge of image processing and low budget.


Assuntos
Automação Laboratorial/métodos , Contagem de Colônia Microbiana/métodos , Processamento de Imagem Assistida por Computador/métodos , Ágar , Automação Laboratorial/instrumentação , Contagem de Colônia Microbiana/instrumentação , Escherichia coli , Processamento de Imagem Assistida por Computador/instrumentação , Reconhecimento Automatizado de Padrão/métodos , Software
11.
Rev. esp. quimioter ; 33(3): 200-206, jun. 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-197878

RESUMO

INTRODUCTION: Bloodstream Infections has become in one of the priorities for the antimicrobial stewardship teams due to their high mortality and morbidity rates. Usually, the first antibiotic treatment for this pathology must be empirical, without microbiology data about the microorganism involved. For this reason, the population studies about the etiology of bacteremia are a key factor to improve the selection of the empirical treatment, because they describe the main microorganisms associated to this pathology in each area, and this data could facilitate the selection of correct antibiotic therapy. MATERIAL AND METHODS: This study describes the etiology of bloodstream infections in the Southeast of Spain. The etiology of bacteremia was analysed by a retrospective review of all age-ranged patients from every public hospital in the Autonomous Community of Valencia (approximately 5,000,000 inhabitants) for five years. RESULTS: A total of 92,097 isolates were obtained, 44.5% of them were coagulase-negative staphylococci. Enterobacteriales was the most prevalent group and an increase in frequency was observed along the time. Streptococcus spp. were the second microorganisms more frequently isolated. Next, the most prevalent were Staphylococcus aureus and Enterococcus spp., both with a stable incidence along the study. Finally, Pseudomonas aeruginosa was the fifth microorganism more frequently solated. CONCLUSIONS: These data constitute a useful tool that can help in the choice of empirical treatment for bloodstream infections, since the knowledge of local epidemiology is key to prescribe a fast and appropriate antibiotic therapy, aspect capital to improve survival


INTRODUCCIÓN: Las bacteriemias se han convertido en una de las prioridades de los Programas de Optimización de uso de Antimicrobianos (PROA) debido a sus altas tasas de morbimortalidad. Normalmente, el tratamiento antibiótico tiene que ser pautado de forma empírica, sin datos del microorganismo implicado. Por esto, los estudios poblacionales sobre la etiología de las bacteriemias son un factor clave para mejorar la elección del tratamiento empírico, ya que describen los principales microorganismos asociados a esta patología en cada área, lo que facilita en gran medida la selección del antibiótico correcto. MATERIAL Y MÉTODOS: Este estudio describe la etiología de las bacteriemias en el sureste de España durante los años 2013-2017. La etología fue analizada de forma retrospectiva estudiando los microorganismos implicados en todas las bacteriemias diagnosticadas en la Comunidad Valenciana (5.000.000 de habitantes). RESULTADOS: Se obtuvieron un total de 92.097 aislados clínicos, de los cuales un 44,5% fueron Staphylococcus coagulasa negativos. Las enterobacterias fueron el grupo más prevalente, su frecuencia se incrementó durante el estudio. Los cocos grampositivos, tipo Streptococcus, fueron los siguientes microorganismos que se aislaron de forma más frecuente, su frecuencia disminuyó a lo largo del periodo estudiado. A continuación, Staphylococcus aureus y Enterococcus spp. les siguieron en prevalencia, manteniéndose sus tasas estables a lo largo del estudio. Por último, el quinto microorganismo más prevalente fue Pseudomonas aeruginosa. CONCLUSIONES: Los datos obtenidos en este estudio constituyen una herramienta que puede facilitar la elección correcta del tratamiento empírico inicial que debe aplicarse en estos procesos


Assuntos
Humanos , Bacteriemia/epidemiologia , Sangue/microbiologia , Hemocultura/métodos , Infecções Bacterianas/epidemiologia , Staphylococcus/isolamento & purificação , Contagem de Colônia Microbiana/métodos , Espanha/epidemiologia , Estudos Retrospectivos , Infecções Estafilocócicas/microbiologia
12.
Food Microbiol ; 87: 103381, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948622

RESUMO

Indirect impedance has been used for the detection and enumeration of bacteria, however there is limited data regarding the ability of the method to measure growth and inhibition of microorganisms in food in response to preservatives. The aim of this study was to evaluate the suitability of the technique to determine maximum growth rates of Listeria innocua (used as a surrogate for Listeria monocytogenes) in complex food matrices to which multiple preservative factors had been applied and assess the suitability of the data for use in predictive microbiology. Growth of L. innocua in laboratory medium (BHI broth) and two food matrices (zucchini purée and béarnaise sauce) under varying conditions of pH (5 & 5.3), water activity (0.93, 0.96 & 0.98) and acetic and propionic acid concentration (0, 1 & 2 mM) was monitored by the conductimetric Rapid Automated Bacterial Impedance Technology (R.A.B.I.T) system by means of CO2 emission for up to 120 h. Growth rates of L. innocua were determined for several conditions across the three test matrices and a good correlation between detection times and initial inoculum level was observed in most cases (R2 ≥ 0.82). However, growth of L. innocua was not detected in a large number of conditions and comparison of growth rates determined by indirect impedance to those determined by plate counts indicated that in general, the R.A.B.I.T. system under-estimated growth. This study demonstrates that there are limitations associated with the technology, and as a result the system may be unsuitable for measuring microbial growth rates in complex food matrices under the environmental conditions tested and within the time duration of the study.


Assuntos
Contagem de Colônia Microbiana/métodos , Técnicas Eletroquímicas/métodos , Microbiologia de Alimentos/métodos , Listeria/química , Listeria/crescimento & desenvolvimento , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Impedância Elétrica , Contaminação de Alimentos/análise , Concentração de Íons de Hidrogênio , Listeria/metabolismo , Listeria monocytogenes/química , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/metabolismo , Água/análise , Água/metabolismo
13.
J Med Microbiol ; 69(2): 228-232, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31922949

RESUMO

Introduction. Rapid and reliable detection of carbapenemase-producing Enterobacterales (CPE) from surveillance cultures is critical in supporting a good infection control programme. We implemented a new algorithm for CPE detection incorporating the NG Test CARBA 5 in January 2019.Aim. Our goals were to compare turnaround time (TAT), costs and staff requirements between the old and new algorithm, and to evaluate the performance of the CARBA 5 test directly on colonies grown on CARBA Smart agar.Methodology. We analysed and compared the TAT of CPE surveillance cultures processed using the old and new CPE screening algorithm. The total actual reagent costs and staff requirements for the new CPE algorithm were compared with the estimated costs and staff requirements of the old CPE algorithm.Results. Of 197 isolates included in the evaluation of the new algorithm, 64 were positive for carbapenemases by both CARBA 5 and Xpert Carba-R assay. Of the 133 that were negative, two were found to harbour NDM and IMI genotypes. Significant improvements in TAT were achieved with 88.7 % of cultures with CPE, reported on the same day as growth was observed on CARBA Smart agar compared to none in the old algorithm. The new algorithm incurred lower costs and, based on our workload, the new algorithm is estimated to save 28.9 man-hours annually.Conclusion. CARBA 5 performs well on colonies growing on CARBA Smart agar and significant improvements in TAT can be achieved without incurring additional costs or staff requirements.


Assuntos
Proteínas de Bactérias/metabolismo , Técnicas de Laboratório Clínico/métodos , Contagem de Colônia Microbiana/métodos , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/isolamento & purificação , Ensaios Enzimáticos/métodos , Algoritmos , Proteínas de Bactérias/genética , Técnicas de Laboratório Clínico/economia , Contagem de Colônia Microbiana/economia , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/diagnóstico , Ensaios Enzimáticos/economia , Humanos , Sensibilidade e Especificidade , beta-Lactamases/genética , beta-Lactamases/metabolismo
14.
Eur J Clin Microbiol Infect Dis ; 39(1): 151-158, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31529306

RESUMO

Shiga toxin-producing Escherichia coli (STEC) and Shigella spp./enteroinvasive E. coli (EIEC) are common diarrheagenic bacteria that cause sporadic diseases and outbreaks. Clinical manifestations vary from mild symptoms to severe complications. For microbiological diagnosis, culture confirmation of a positive stool screening PCR test is challenging because of time-consuming methods for isolation of strains, wide variety of STEC pathotypes, and increased emergence of non-classical strains with unusual serotypes. Therefore, molecular assays for the rapid identification of suspect colonies growing on selective media are very useful. In this study, the performance of the newly introduced eazyplex® EHEC assay based on loop-mediated isothermal amplification (LAMP) was evaluated using 18 representative STEC and Shigella strains and 31 isolates or positive-enrichment broths that were collected from clinical stool samples following screening by BD MAX™ EBP PCR. Results were compared to real-time PCR as a reference standard. Overall, sensitivities and specificities of the eazyplex® EHEC were as follows: 94.7% and 100% for Shiga toxin 1 (stx1), 100% and 100% for stx2, 93.3% and 97.1% for intimin (eae), 100% and 100% for enterohemolysin A (ehlyA), and 100% and 100% for invasion-associated plasmid antigen H (ipaH) as Shigella spp./EIEC target, respectively. Sample preparation for LAMP took only some minutes, and the time to result of the assay ranged from 8.5 to 13 min. This study shows that eazyplex® EHEC is a very fast and easy to perform molecular assay that provides reliable results as a culture confirmation assay for the diagnosis of STEC and Shigella spp./EIEC infections.


Assuntos
Escherichia coli Êntero-Hemorrágica/isolamento & purificação , Microbiologia de Alimentos/métodos , Escherichia coli Shiga Toxigênica/isolamento & purificação , Shigella/isolamento & purificação , Adulto , Pré-Escolar , Contagem de Colônia Microbiana/métodos , Meios de Cultura/química , DNA Bacteriano/isolamento & purificação , Disenteria Bacilar/diagnóstico , Disenteria Bacilar/microbiologia , Escherichia coli Êntero-Hemorrágica/genética , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Feminino , Humanos , Técnicas de Amplificação de Ácido Nucleico/métodos , Estudos Prospectivos , Sensibilidade e Especificidade , Escherichia coli Shiga Toxigênica/genética , Shigella/genética
15.
Cold Spring Harb Protoc ; 2019(12)2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792144

RESUMO

Many plasmid vectors (e.g., the pUC series, Bluescript, pGem, and their derivatives) carry a short segment of Escherichia coli DNA containing the regulatory sequences and the coding information for the first 146 amino acids of ß-galactosidase. Vectors of this type are used in host cells that express the carboxy-terminal portion of ß-galactosidase. Although neither the host-encoded fragments nor the plasmid-encoded fragments of ß-galactosidase are themselves active, they can associate to form an enzymatically active protein. This type of complementation, in which deletion mutants of the operator-proximal segment of the lacZ gene are complemented by ß-galactosidase-negative mutants that have the operator-proximal region intact, is called α-complementation. The lac+ bacteria that result from α-complementation are easily recognized because they form blue colonies in the presence of the chromogenic substrate X-Gal. However, insertion of a fragment of foreign DNA into the polycloning site of the plasmid almost invariably results in production of an amino-terminal fragment that is no longer capable of α-complementation. Bacteria carrying recombinant plasmids therefore form white colonies. To screen bacterial colonies, the chromogenic substrate X-Gal and the gratuitous inducer IPTG are mixed with suitable dilution of a culture, combined with molten top agar, and then spread on agar plates containing the appropriate antibiotic. The efficiency of transformation is slightly higher when the bacteria are plated in top agar rather than on the surface of agar plates. Perhaps the transformed bacteria prefer the slightly anaerobic state within the soft agar or the isosmolarity provided by the agar medium.


Assuntos
Contagem de Colônia Microbiana/métodos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/isolamento & purificação , Galactosídeos/metabolismo , Indóis/metabolismo , Isopropiltiogalactosídeo/metabolismo , Plasmídeos/genética , Recombinação Genética
16.
Sensors (Basel) ; 19(24)2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31817434

RESUMO

The measurement of microbial contamination is of primary importance in different fields, from environmental monitoring to food safety and clinical analysis. Today, almost all microbiology laboratories make microbial concentration measurements using the standard Plate Count Technique (PCT), a manual method that must be performed by trained personnel. Since manual PCT analysis can result in eye fatigue and errors, in particular when hundreds of samples are processed every day, automatic colony counters have been built and are commercially available. While quick and reliable, these instruments are generally expensive, thus, portable colony counters based on smartphones have been developed and are of low cost but also not accurate as the commercial benchtop instruments. In this paper, a novel computer vision sensor system is presented that can measure the microbial concentration of a sample under test and also estimate the microbial growth kinetics by monitoring the colonies grown on a Petri dish at regular time intervals. The proposed method has been in-house validated by performing PCT analysis in parallel under the same conditions and using these results as a reference. All the measurements have been carried out in a laboratory using benchtop instruments, however, such a system can also be realized as an embedded sensor system to be deployed for microbial analysis outside a laboratory environment.


Assuntos
Bactérias/crescimento & desenvolvimento , Contagem de Colônia Microbiana/métodos , Algoritmos , Bactérias/citologia , Contagem de Colônia Microbiana/instrumentação , Processamento de Imagem Assistida por Computador , Cinética
17.
Molecules ; 24(22)2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31717511

RESUMO

This study aims to investigate the effect of essential oils extracted from wood residues of Picea abies on the growth of Escherichia coli. The essential oils were extracted by supercritical carbon dioxide, leading to a yield of 3.4 ± 0.5% (w/w) in 120 min. The antimicrobial effect was tested at 37 °C by isothermal calorimetry. The heat-flow (dq/dt vs. time) was integrated to give a fractional reaction curve (α vs. time). Such curves were fitted by a modified Gompertz function to give the lag-time (λ) and the maximum growth rate (µmax) parameters. The results showed that λ was linearly correlated with E. coli concentration (λ = 1.4 h/log (CFU/mL), R2 = 0.997), whereas µmax was invariant. Moreover, the overall heat was nearly constant to all the dilutions of E. coli. Instead, when the essential oil was added (with concentrations ranging from 1 to 5 mg/L) to a culture of E. coli (104 CFU/mL), the lag-time increased from 14.1 to 33.7 h, and the overall heat decreased from 2120 to 2.37 J. The results obtained by the plate count technique were linear with the lag-time (λ), where (λ = -7.3 × log (CFU/mL) + 38.3, R2 = 0.9878). This suggested a lower capacity of E. coli to metabolize the substrate in the presence of the essential oils. The results obtained in this study promote the use of essential oils from wood residues and their use as antimicrobial products.


Assuntos
Anti-Infecciosos/farmacologia , Escherichia coli/efeitos dos fármacos , Picea/química , Extratos Vegetais/farmacologia , Abies/química , Contagem de Colônia Microbiana/métodos , Óleos Voláteis/farmacologia
18.
J Microbiol Methods ; 167: 105778, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31733264

RESUMO

This study demonstrates an effective technique for separating and purifying viable bacteria from samples that interfere with viability staining. The viability of Bifidobacterium longum ATCC 15707 was assessed using Percoll Buoyant Density Gradient Centrifugation (PBDC) to separate bacteria from complex non-dairy food matrices and Quantitative Fluorescence Microscopy (QFM) to determine individual cells using LIVE/DEAD BacLight bacterial viability staining. Water agar (3%) was used to retain cells of B. longum and offered a lower fluorescence background with BacLight viability staining, compared with fixation on polycarbonate (PC) black membrane. The effect of drying temperatures and non-dairy foods on viability of B. longum was assessed. B. longum coated on oat, peanut or raisin was separated by filtration, low- and high-speed centrifugation, flotation and sedimentation buoyant density centrifugation. Purified cells were subsequently deposited on water agar for rehydration followed by LIVE/DEAD BacLight viability staining and enumeration. Conventional plate counting was also conducted to compare viability results. Finally, this method was applied to assess cell membrane damages of B. longum incorporated onto non-dairy foods during 24 h drying. Furthermore, viability assessment of B. longum coated onto oat, peanut, or raisin was much lower by plate counting compared to viability staining. Drying appeared to have a greater impact when viability was assessed by plate counting compared to viability staining. IMPORTANCE: Enumeration of viable beneficial bacteria from function foods presents a significant bottleneck for product development and quality control. Interference with microscopic and/or fluorescent techniques by ingredients, time required to incubate plated microbes, and the transient nature of the colony forming unit make rapid assessment of viable bacteria difficult. Viability assessment of Bifidobacterium longum ATCC 15707 by Percoll Buoyant Density Gradient Centrifugation with LIVE/DEAD BacLight viability staining on water agar (3%) was in agreement with serial dilution enumeration. Without the need for incubation viability assessment by staining provided a more rapid means to assess the impact of drying on the viability of B. longum coated onto oat, peanut or raisin.


Assuntos
Bifidobacterium longum/crescimento & desenvolvimento , Microbiologia de Alimentos/métodos , Viabilidade Microbiana , Microscopia de Fluorescência/métodos , Centrifugação com Gradiente de Concentração/métodos , Contagem de Colônia Microbiana/métodos , Povidona , Dióxido de Silício , Coloração e Rotulagem/métodos
19.
J Microbiol Methods ; 167: 105725, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31629913

RESUMO

The Acridine orange direct count (AODC) enables the determination of total cell count (TCC) in building materials. The AODC technique is considered as an analytic standard in many different areas but is not common in the indoor environment. In this paper AODC was tested with various building materials to investigate TCC. Colony forming units (CFU) only detect viable cells in contrast to the TCC assay which estimates total microbial contamination. The results show that the total cell count is a reliable and sensitive method to investigate the indoor environment.


Assuntos
Laranja de Acridina , Bactérias/isolamento & purificação , Técnicas Bacteriológicas/métodos , Materiais de Construção/microbiologia , Fungos/isolamento & purificação , Poluição do Ar em Ambientes Fechados/análise , Contagem de Colônia Microbiana/métodos , Esporos Fúngicos/isolamento & purificação , Coloração e Rotulagem/métodos
20.
Acta Med Port ; 32(9): 568-575, 2019 Sep 02.
Artigo em Português | MEDLINE | ID: mdl-31493359

RESUMO

INTRODUCTION: Urinary tract infections in the community setting are quite common. It is necessary to be aware of antibiotic susceptibility patterns in order to provide rational empirical therapy. The aim of this study is to determine the frequency and antimicrobial susceptibility of the strains responsible for urinary tract infections in primary health care, in the district of Coimbra, Portugal. MATERIAL AND METHODS: In this observational and cross-sectional study, we analyzed 7134 positive urine cultures of outpatient laboratories in the district of Coimbra, over one year. In most cases, a positive culture was defined by a threshold of 105 colony-forming units per milliliter and was conducted by the automated system VITEK® 2, by bioMérieux. We used descriptive and inferential statistics to determine the prevalence and antimicrobial susceptibility of bacteria and to ascertain whether there were differences associated with sex and age. RESULTS: From the total of positive cultures, 83.4% pertained to females and 41.0% to individuals over 75 years old. Escherichia coli was the most frequent strain (63.9%), although its prevalence was lower (p < 0.001) in males and individuals over 75 years old. Its susceptibility to fosfomycin and nitrofurantoin was higher than 95% and with ciprofloxacin and trimethoprim/sulfamethoxazole it was lower than 80%. Resistances were more frequent (p < 0.001) in males and in the elderly. DISCUSSION: Escherichia coli was the most frequent strain, revealing less resistance to fosfomycin and nitrofurantoin. Antimicrobial susceptibility was lower in the elderly and in males, populations in whom empirical therapy may be less successful. CONCLUSION: In order to improve clinical results, we recommend periodic surveillance of antimicrobial susceptibility, which could enable the provision of efficient information to clinicians, namely those who prescribe empirically for such infections, as well as standardization of identification methods of bacterial strains diagnosis and of the antibiotic kits to be tested.


Assuntos
Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Infecções Urinárias/tratamento farmacológico , Fatores Etários , Anti-Infecciosos Urinários/farmacologia , Técnicas Bacteriológicas/métodos , Contagem de Colônia Microbiana/métodos , Estudos Transversais , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Feminino , Humanos , Masculino , Portugal , Fatores Sexuais , Infecções Urinárias/microbiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...