RESUMO
This study evaluated the effect of contamination of composite resins (CRs) handled by undergraduate students during restorative procedures, varying the time (baseline, 30 days and 60 days) and experimental condition (before and after handling, contamination with saliva [positive control] and photoactivation). Eight CR tubes were randomly distributed at the dental clinic and the samples were organized into four groups: CR fragments collected before (GB) and after (GA) the restorative procedure; CR fragments contaminated with saliva (GS) and photoactivated (GP) both collected after the procedure. These 4 groups were evaluated in 3 different times: baseline (after sealing), 30 days and 60 days of use of the CR. Samples that had positive turbidity in Brain HeartInfusion (BHI) broth were sown in BHI and Sabouraud Dextrose (SB) agars for subsequent counting of Colony Forming Units (CFU mL-1). The results showed that the handling was responsible for increasing contamination (p < 0.05) at the baseline (GB [n = 0] and GA [n = 3]), as well as after 30 (GB [n = 1] and GA [n = 6]) and 60 (GB [n = 1] and GA [n = 5]) days of use. Photoactivation was responsible for the reduction for microorganisms in T0 and T60. Additionally, the time use and conservation did not influencethe contamination of CRs. Handling was responsible for the increase of contamination of CR, the photoactivation seems to reduce the number of viable microorganisms and the time of use seems not to potentiate the effect of tube contamination.
Assuntos
Indicadores de Contaminação , Resinas Compostas/análise , Boas Práticas de Manipulação , Cura Luminosa de Adesivos Dentários/instrumentação , Estudantes de Odontologia , Interpretação Estatística de Dados , Recuperação e Remediação Ambiental , Conservantes de Alimentos/análise , Microbiologia/instrumentaçãoRESUMO
A set of three apparatus enabling RF exposure of aerosolized pathogens at four chosen frequencies (2.8 GHz, 4.0 GHz, 5.6 GHz, and 7.5 GHz) has been designed, simulated, fabricated, and tested. Each apparatus was intended to operate at high power without leakage of RF into the local environment and to be compact enough to fit within biocontainment enclosures required for elevated biosafety levels. Predictions for the range of RF electric field exposure, represented by the complex electric field vector magnitude, that an aerosol stream would be expected to encounter while passing through the apparatus are calculated for each of the chosen operating frequencies.
Assuntos
Aerossóis , Microbiologia/instrumentação , Micro-OndasRESUMO
The injection of laboratory animals with pathogenic microorganisms poses a significant safety risk because of the potential for injury by accidental needlestick. This is especially true for researchers using invertebrate models of disease due to the required precision and accuracy of the injection. The restraint of the greater wax moth larvae (Galleria mellonella) is often achieved by grasping a larva firmly between finger and thumb. Needle resistant gloves or forceps can be used to reduce the risk of a needlestick but can result in animal injury, a loss of throughput, and inconsistencies in experimental data. Restraint devices are commonly used for the manipulation of small mammals, and in this manuscript, we describe the construction of two devices that can be used to entrap and restrain G. mellonella larvae prior to injection with pathogenic microbes. These devices reduce the manual handling of larvae and provide an engineering control to protect against accidental needlestick injury while maintaining a high rate of injection.
Assuntos
Injeções/instrumentação , Microbiologia/instrumentação , Mariposas/microbiologia , Prevenção de Acidentes , Animais , Descontaminação/instrumentação , Reutilização de Equipamento , Larva/microbiologiaRESUMO
Application of the impedance spectroscopy technique to detection of bacteria has advanced considerably over the last decade. This is reflected by the large amount of publications focused on basic research and applications of impedance biosensors. Employment of modern technologies to significantly reduce dimension of impedimetric devices enable on-chip integration of interdigitated electrode arrays for low-cost and easy-to-use sensors. This review is focused on publications dealing with interdigitated electrodes as a transducer unit and different bacteria detection systems using these devices. The first part of the review deals with the impedance technique principles, paying special attention to the use of interdigitated electrodes, while the main part of this work is focused on applications ranging from bacterial growth monitoring to label-free specific bacteria detection.
Assuntos
Bactérias/isolamento & purificação , Microbiologia/instrumentação , Transdutores , Impedância Elétrica , Eletrodos , HumanosRESUMO
INTRODUÇÃO: A automação laboratorial é cada vez mais utilizada em microbiologia, no entanto, poucos estudos avaliam desfechos clínicos em comparação aos métodos tradicionais. No Brasil, nenhum estudo com esse objetivo foi detectado. OBJETIVO: Analisar os impactos clínicos e microbiológicos após implantação de método fenotípico automatizado em um serviço de microbiologia. MÉTODOS: Realizamos estudo observacional e retrospectivo no laboratório de microbiologia referente a exame de hemocultura de pacientes da Unidade de Terapia Intensiva (UTI). Os dados foram coletados de pacientes internados entre janeiro/2014 a dezembro/2015. Analisou-se o tempo de internação, número de terapias empíricas, óbitos e dados relacionados ao isolamento microbiológico. A amostra foi obtida por conveniência. Para a comparação entre os desfechos foram empregados os testes t de Student e Qui-quadrado de Pearson. O programa empregado foi o Stata release, versão 11, sendo considerados significativos valores de p<0,05. RESULTADOS: Foram avaliados 472 pacientes. Não houve redução na prescrição empírica de antimicrobianos (54,7% vs 45,3%; p=0,33), tempo de internação na UTI (14,5 dias vs 15,8 dias p=0,78) e na taxa de óbitos (54,4% vs 45,6%; p=0,36). Similarmente, o perfil de agentes isolados em ambos os métodos não parece ser discrepante, no entanto, houve um aumento de 44,7% no número de isolados microbianos (76 vs 110) com melhor caracterização dos mesmos. CONCLUSÃO: A automação do laboratório de microbiologia não impactou no tempo de internação, mortalidade na UTI e no número de terapias empíricas. No entanto, a identificação e o isolamento de microrganismos melhoraram.
INTRODUCTION: Automation is increasingly used in microbiology laboratory, however, few studies assessed clinical outcomes compared to traditional methods. In Brazil, no studies with this objective were detected. OBJECTIVE: To analyze the clinical and microbiological impacts after implantation of an automated phenotypic method in a microbiology service. METHODS: Observational and retrospective study carried out on the microbiology laboratory involving blood culture test from intensive care unit (ICU) patients. Data were collected from hospitalized patients between January 2014 and December 2015. The length of hospitalization, number of empirical therapies, deaths and information related to microbiological isolation were analyzed. The sample was obtained by convenience. Pearson's Chisquare and Student's t-tests were used to compare outcomes. The program used was the Stata release, version 11, being considered significant values of p<0.05. RESULTS: A total of 472 patients were evaluated. There was no reduction in the empirical prescription of antimicrobials (54.7% vs 45.3%; p=0.33), ICU stay (14.5 days vs 15.8 days; p=0.78) and mortality (54.4% vs 45.6%; p=0.36). Similarly, profile of isolated agents in both methods did not appear to be discrepant, however, there was an increase of 44.7% in the number of microbial isolates (76 vs 110) and a better characterization of them. CONCLUSION: The microbiology laboratory automation did not modify the length of stay, ICU mortality and the number of empirical therapies. However, identification and isolation of microorganisms was improved.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Testes de Sensibilidade Microbiana/instrumentação , Testes de Sensibilidade Microbiana/métodos , Automação Laboratorial/instrumentação , Automação Laboratorial/métodos , Hemocultura/instrumentação , Hemocultura/métodos , Microbiologia/instrumentaçãoRESUMO
The aim of this study was to develop an audit tool with a built-in database using Research Electronic Data Capture (REDCap®) as part of an antimicrobial stewardship program at a regional hospital in the Central Denmark Region, and to analyse the need, if any, to involve more than one expert in the evaluation of cases of antimicrobial treatment, and the level of agreement among the experts. Patients treated with systemic antimicrobials in the period from 1 September 2015 to 31 August 2016 were included, in total 722 cases. Data were collected retrospectively and entered manually. The audit was based on seven flow charts regarding: (1) initiation of antimicrobial treatment (2) infection (3) prescription and administration of antimicrobials (4) discontinuation of antimicrobials (5) reassessment within 48â¯h after the first prescription of antimicrobials (6) microbiological sampling in the period between suspicion of infection and the first administration of antimicrobials (7) microbiological results. The audit was based on automatic calculations drawing on the entered data and on expert assessments. Initially, two experts completed the audit, and in the cases in which they disagreed, a third expert was consulted. In 31.9% of the cases, the two experts agreed on all elements of the audit. In 66.2%, the two experts reached agreement by discussing the cases. Finally, 1.9% of the cases were completed in cooperation with a third expert. The experts assessed 3406 flow charts of which they agreed on 75.8%. We succeeded in creating an audit tool with a built-in database that facilitates independent expert evaluation using REDCap. We found a large inter-observer difference that needs to be considered when constructing a project based on expert judgements. Our two experts agreed on most of the flow charts after discussion, whereas the third expert's intervention did not have any influence on the overall assessment.
Assuntos
Gestão de Antimicrobianos , Informática Médica/métodos , Microbiologia/instrumentação , Anti-Infecciosos/uso terapêutico , Bases de Dados Factuais , Humanos , Infectologia/instrumentação , Infectologia/métodos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Fluxo de TrabalhoRESUMO
Continuous culture techniques were developed in the early twentieth century to replace cumbersome studies of cell growth in batch cultures. In contrast to batch cultures, they constituted an open concept, as cells are forced to proliferate by adding new medium while cell suspension is constantly removed. During the 1940s and 1950s new devices have been designed-called "automatic syringe mechanism," "turbidostat," "chemostat," "bactogen," and "microbial auxanometer"-which allowed increasingly accurate quantitative measurements of bacterial growth. With these devices cell growth came under the external control of the experimenters and thus accessible for developing a mathematical theory of growth kinetics-developed mainly by Jacques Monod, Aron Novick and Leo Szilard in the early 1950s and still in use today. The paper explores the development of continuous culture devices and claims that these devices are simulators for standard cells following specific requirements, in particular involving mathematical constraints in the design and setting of the devices as well as experiments. These requirements have led to contemporary designs of continuous culture techniques realizing a specific event-based flow algorithm able to simulate directed evolution and produce artificial cells and microorganisms. This current development is seen as an alternative approach to today's synthetic biology.
Assuntos
Técnicas de Cultura/história , Microbiologia/história , Técnicas de Cultura/instrumentação , História do Século XX , Microbiologia/instrumentação , Projetos de PesquisaRESUMO
The Food and Drug Administration (FDA, Agency, or we) is classifying the assayed quality control material for clinical microbiology assays into class II (special controls). The special controls that will apply to the device are identified in this order and will be part of the codified language for the assayed quality control material for clinical microbiology assays' classification. The Agency is classifying the device into class II (special controls) to provide a reasonable assurance of safety and effectiveness of the device.
Assuntos
Segurança de Equipamentos/classificação , Técnicas Microbiológicas/classificação , Técnicas Microbiológicas/instrumentação , Microbiologia/classificação , Microbiologia/instrumentação , Controle de Qualidade , HumanosAssuntos
Bactérias/química , Bactérias/classificação , Técnicas de Tipagem Bacteriana , Técnicas de Laboratório Clínico , Educação , Microbiologia/educação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , Proteínas de Bactérias/análise , Humanos , Microbiologia/instrumentação , Proteômica/instrumentaçãoRESUMO
Microbial cells have developed sophisticated multicomponent structures and machineries to govern basic cellular processes, such as chromosome segregation, gene expression, cell division, mechanosensing, cell adhesion and biofilm formation. Because of the small cell sizes, subcellular structures have long been difficult to visualize using diffraction-limited light microscopy. During the last three decades, optical and force nanoscopy techniques have been developed to probe intracellular and extracellular structures with unprecedented resolutions, enabling researchers to study their organization, dynamics and interactions in individual cells, at the single-molecule level, from the inside out, and all the way up to cell-cell interactions in microbial communities. In this Review, we discuss the principles, advantages and limitations of the main optical and force nanoscopy techniques available in microbiology, and we highlight some outstanding questions that these new tools may help to answer.
Assuntos
Microbiologia/instrumentação , Microscopia de Força Atômica/métodos , Nanotecnologia/instrumentação , Bactérias/ultraestrutura , Adesão Celular , Membrana Celular , Fenômenos Mecânicos , Técnicas Microbiológicas , Microscopia de Força Atômica/instrumentação , Microscopia de Fluorescência/métodos , Nanotecnologia/métodos , Imagem Óptica , Fenômenos FísicosRESUMO
This paper describes mass production system of micro-tubes for microbial culture in an open environment. Microbes are used in many fields, such as food, medicine, environmental and energy. We proposed a microbe culture system using hydrogel micro-tubes, which can protect the target microbes inside from competitive microbes outside of the tubes while allow oxygen and nutrition to diffuse through. The hydrogel micro-tubes can be produced by a microfluidic device, which can precisely control the flow and therefore, the tube geometry. For practical applications of the micro-tube-based microbial culture, one of the biggest challenges is the scale-up of the micro-tube-based culture system, or mass production of the tubes. We developed a fluidic system that can produce multiple micro-tubes in parallel. We characterized the mass-produced micro channels and verified the effectiveness of the system.
Assuntos
Técnicas de Cultura/instrumentação , Microbiologia/instrumentação , Microtecnologia/instrumentação , Hidrogel de Polietilenoglicol-DimetacrilatoRESUMO
Although not laying claim to being the inventor of the light microscope, Antonj van Leeuwenhoek (1632-1723) was arguably the first person to bring this new technological wonder of the age properly to the attention of natural scientists interested in the study of living things (people we might now term 'biologists'). He was a Dutch draper with no formal scientific training. From using magnifying glasses to observe threads in cloth, he went on to develop over 500 simple single lens microscopes (Baker & Leeuwenhoek 1739 Phil. Trans. 41, 503-519. (doi:10.1098/rstl.1739.0085)) which he used to observe many different biological samples. He communicated his finding to the Royal Society in a series of letters (Leeuwenhoek 1800 The select works of Antony Van Leeuwenhoek, containing his microscopical discoveries in many of the works of nature, vol. 1) including the one republished in this edition of Open Biology. Our review here begins with the work of van Leeuwenhoek before summarizing the key developments over the last ca 300 years, which has seen the light microscope evolve from a simple single lens device of van Leeuwenhoek's day into an instrument capable of observing the dynamics of single biological molecules inside living cells, and to tracking every cell nucleus in the development of whole embryos and plants.
Assuntos
Microbiologia/história , Microbiologia/instrumentação , Microscopia/história , Microscopia/tendências , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Países BaixosRESUMO
Hyperspectral chemical imaging (HSI) is a broad term encompassing spatially resolved spectral data obtained through a variety of modalities (e.g. Raman scattering, Fourier transform infrared microscopy, fluorescence and near-infrared chemical imaging). It goes beyond the capabilities of conventional imaging and spectroscopy by obtaining spatially resolved spectra from objects at spatial resolutions varying from the level of single cells up to macroscopic objects (e.g. foods). In tandem with recent developments in instrumentation and sampling protocols, applications of HSI in microbiology have increased rapidly. This article gives a brief overview of the fundamentals of HSI and a comprehensive review of applications of HSI in microbiology over the past 10 years. Technical challenges and future perspectives for these techniques are also discussed.
Assuntos
Microbiologia , Imagem Óptica/métodos , Análise Espectral , Animais , Microbiologia/instrumentação , Imagem Óptica/instrumentação , Estatística como AssuntoRESUMO
The Food and Drug Administration (FDA) is classifying nucleic acid-based in vitro diagnostic devices for the detection of Mycobacterium tuberculosis complex (MTB-complex) and the genetic mutations associated with MTB-complex antibiotic resistance in respiratory specimens devices into class II (special controls). The Agency is classifying the device into class II (special controls) because special controls, in addition to general controls, will provide a reasonable assurance of safety and effectiveness of the device.
Assuntos
Aprovação de Equipamentos/legislação & jurisprudência , Farmacorresistência Bacteriana/genética , Microbiologia/instrumentação , Mycobacterium tuberculosis/genética , Ácidos Nucleicos , Kit de Reagentes para Diagnóstico/classificação , Tuberculose/diagnóstico , Humanos , Microbiologia/classificação , Mutação , Tuberculose/genética , Estados UnidosRESUMO
The clinical microbiology laboratory has responsibilities ranging from characterizing the causative agent in a patient's infection to helping detect global disease outbreaks. All of these processes are increasingly becoming partnered more intimately with informatics. Effective application of informatics tools can increase the accuracy, timeliness, and completeness of microbiology testing while decreasing the laboratory workload, which can lead to optimized laboratory workflow and decreased costs. Informatics is poised to be increasingly relevant in clinical microbiology, with the advent of total laboratory automation, complex instrument interfaces, electronic health records, clinical decision support tools, and the clinical implementation of microbial genome sequencing. This review discusses the diverse informatics aspects that are relevant to the clinical microbiology laboratory, including the following: the microbiology laboratory information system, decision support tools, expert systems, instrument interfaces, total laboratory automation, telemicrobiology, automated image analysis, nucleic acid sequence databases, electronic reporting of infectious agents to public health agencies, and disease outbreak surveillance. The breadth and utility of informatics tools used in clinical microbiology have made them indispensable to contemporary clinical and laboratory practice. Continued advances in technology and development of these informatics tools will further improve patient and public health care in the future.
Assuntos
Informática Médica , Microbiologia , Automação Laboratorial , Sistemas de Informação em Laboratório Clínico/instrumentação , Notificação de Doenças , Humanos , Informática Médica/instrumentação , Informática Médica/métodos , Técnicas Microbiológicas/instrumentação , Técnicas Microbiológicas/métodos , Microbiologia/instrumentação , Microbiologia/normasRESUMO
The stratosphere is a known host to terrestrial microbes of most major biological lineages, but it is also host to incoming meteoric dust. Our goal is to (1) introduce DUSTER (Dust in the Upper Stratosphere Tracking Experiment and Retrieval), an active collector for the nondestructive collection of nano- to micrometer particles in the stratosphere between 30 and 40 km altitude, and (2) demonstrate that even a single particle can be collected free of resident atmospheric and laboratory contaminant particles. DUSTER improves the pervasive and persistent contamination problem in the field of aerobiology research. Here, we demonstrate the collector's advances by the identification of a (terrestrial) spore particle found among a population of nanometer-scale inorganic meteoric particles. This was possible because the size, shape, morphology, and chemical composition of each particle can be determined while still on the collector surface. Particles can be removed from DUSTER for specific laboratory analyses. So far, DUSTER has not been fitted for aerobiological purposes; that is, no attempts were made to sterilize the collector other than with isopropyl alcohol. Its design and laboratory protocols, however, allow adjustments to dedicated aerobiological sampling opportunities.
Assuntos
Microbiologia do Ar , Atmosfera , Poeira/análise , Microbiologia/instrumentaçãoRESUMO
The last few years have witnessed a revolution in the diagnostic microbiology laboratory with the emergence of matrix assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) as an indispensible tool in microbial identification. In many laboratories this has superseded biochemical profiling. A mass spectrum is acquired from an unknown micro-organism and this proteomic fingerprint is then compared with a database of reference spectra to ascertain the likely genus and species identity. The reproducibility of this method is facilitated by the analysis of continually produced, highly abundant proteins (mainly ribosomal proteins) in the mass range 2000 to 20â 000â Da. MALDI-TOF MS is reliable and rapid and has the ability to determine the identity of an isolate from culture in a matter of minutes rather than the hours or days required by more traditional methods. In addition to microbial identification of cultured isolates, work is underway to extend the utility of MALDI-TOF MS to include bacterial identification directly from clinical samples as well as providing timely information regarding antibiotic resistance and typing of different micro-organisms.