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1.
Arch Microbiol ; 206(4): 198, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558101

RESUMO

Micro- plastics (MPs) pose significant global threats, requiring an environment-friendly mode of decomposition. Microbial-mediated biodegradation and biodeterioration of micro-plastics (MPs) have been widely known for their cost-effectiveness, and environment-friendly techniques for removing MPs. MPs resistance to various biocidal microbes has also been reported by various studies. The biocidal resistance degree of biodegradability and/or microbiological susceptibility of MPs can be determined by defacement, structural deformation, erosion, degree of plasticizer degradation, metabolization, and/or solubilization of MPs. The degradation of microplastics involves microbial organisms like bacteria, mold, yeast, algae, and associated enzymes. Analytical and microbiological techniques monitor microplastic biodegradation, but no microbial organism can eliminate microplastics. MPs can pose environmental risks to aquatic and human life. Micro-plastic biodegradation involves fragmentation, assimilation, and mineralization, influenced by abiotic and biotic factors. Environmental factors and pre-treatment agents can naturally degrade large polymers or induce bio-fragmentation, which may impact their efficiency. A clear understanding of MPs pollution and the microbial degradation process is crucial for mitigating its effects. The study aimed to identify deteriogenic microorganism species that contribute to the biodegradation of micro-plastics (MPs). This knowledge is crucial for designing novel biodeterioration and biodegradation formulations, both lab-scale and industrial, that exhibit MPs-cidal actions, potentially predicting MPs-free aquatic and atmospheric environments. The study emphasizes the urgent need for global cooperation, research advancements, and public involvement to reduce micro-plastic contamination through policy proposals and improved waste management practices.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Plásticos , Biodegradação Ambiental , Indústrias , Técnicas Microbiológicas
3.
J Med Microbiol ; 73(2)2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38305344

RESUMO

The coronavirus disease 2019 pandemic accelerated developments in biotechnology that underpin infection science. These advances present an opportunity to refresh the microbial forensic toolkit. Integration of novel analytical techniques with established forensic methods will speed up acquisition of evidence and better support lines of enquiry. A critical part of any such investigation is demonstration of a robust causal relationship and attribution of responsibility for an incident. In the wider context of a formal investigation into agency, motivation and intent, the quick and efficient assembly of microbiological evidence sets the tone and tempo of the entire investigation. Integration of established and novel analytical techniques from infection science into a systematic approach to microbial forensics will therefore ensure that major perspectives are correctly used to frame and shape the evidence into a clear narrative, while recognizing that forensic hypothesis generation, testing and refinement comprise an iterative process. Development of multidisciplinary training exercises that use this approach will enable translation into practice and efficient implementation when the need arises.


Assuntos
Bioterrorismo , Microbiologia Forense , Técnicas Microbiológicas/métodos
4.
Clin Lab Med ; 44(1): 63-73, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38280798

RESUMO

Next-generation sequencing (NGS)-based assays are primarily available from reference laboratories for diagnostic use. These tests can provide helpful diagnostic data but also can be overused by ordering providers not fully understanding their limitations. At present, there are few best practice guidelines for use. NGS-based assays can carry a high cost to institutions and individual patients, requiring thoughtful use through application of diagnostic stewardship principles. This article provides an overview of diagnostic stewardship approaches as applied to these assays, focusing on principles of collaboration, differential diagnosis formation, and seeking the best patient, syndrome, sample, timing, and test for improved patient care.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Técnicas Microbiológicas
5.
Clin Lab Med ; 44(1): 33-43, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38280796

RESUMO

As infectious disease diagnostics increasingly incorporates molecular techniques, there are unique preanalytical concerns that must be considered. First, noninvasive specimen types that may be inadequate for culture-based diagnostics may be acceptable when using molecular tests. Second, specimen containers must be evaluated for the presence of substances that may interfere with amplification or sequencing reactions. Finally, the capacity of transport, storage, and processing conditions to maintain nucleic acid integrity and avoid contamination must be assessed. This review explores these issues and the effects they may have on result quality.


Assuntos
Técnicas Microbiológicas , Manejo de Espécimes , Manejo de Espécimes/métodos
6.
J Biol Chem ; 300(3): 105676, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38278326

RESUMO

Infectious diseases are one of the world's leading causes of morbidity. Their rapid spread emphasizes the need for accurate and fast diagnostic methods for large-scale screening. Here, we describe a robust method for the detection of pathogens based on microscale thermophoresis (MST). The method involves the hybridization of a fluorescently labeled DNA probe to a target RNA and the assessment of thermophoretic migration of the resulting complex in solution within a 2 to 30-time window. We found that the thermophoretic migration of the nucleic acid-based probes is primarily determined by the fluorescent molecule used, rather than the nucleic acid sequence of the probe. Furthermore, a panel of uniformly labeled probes that bind to the same target RNA yields a more responsive detection pattern than a single probe, and moreover, can be used for the detection of specific pathogen variants. In addition, intercalating agents (ICA) can be used to alter migration directionality to improve detection sensitivity and resolving power by several orders of magnitude. We show that this approach can rapidly diagnose viral SARS-CoV2, influenza H1N1, artificial pathogen targets, and bacterial infections. Furthermore, it can be used for anti-microbial resistance testing within 2 h, demonstrating its diagnostic potential for early pathogen detection.


Assuntos
Ensaios de Triagem em Larga Escala , Técnicas Microbiológicas , Técnicas de Diagnóstico Molecular , Hibridização de Ácido Nucleico , RNA , Sondas de DNA , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/normas , Técnicas Microbiológicas/métodos , Técnicas Microbiológicas/normas , Ensaios de Triagem em Larga Escala/métodos , Ensaios de Triagem em Larga Escala/normas , RNA/análise , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Viroses/diagnóstico , Infecções Bacterianas/diagnóstico , Linhagem Celular Tumoral , Humanos
7.
Methods Mol Biol ; 2967: 63-73, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37608103

RESUMO

Shiga toxin-producing Escherichia coli (STEC) is a group of human foodborne pathogens transmitted to humans through the consumption of different types of food. Their detection is mainly performed by targeting specific serogroups by classical microbiological methods and, later, by molecular typing with different techniques. The application of multiplex real-time PCR (qPCR) can significantly improve the turnaround time of the existing methodologies as in one single run it is possible to detect and characterize specific microorganisms. In the present chapter, a pentaplex qPCR assay is described for the identification of STEC which may also be applied for the rapid screening of these pathogens in different types of foods. The assay targets the most important virulence factors of these microorganisms, the genes stx1, stx2, and eae, along with the rfbE gene which encodes for the "O157" antigen as this is the most prevalent serogroup among all STEC, as well as an internal amplification control to rule out false-negative results due to qPCR inhibition.


Assuntos
Escherichia coli Shiga Toxigênica , Humanos , Escherichia coli Shiga Toxigênica/genética , Reação em Cadeia da Polimerase em Tempo Real , Alimentos , Bioensaio , Técnicas Microbiológicas
8.
PDA J Pharm Sci Technol ; 77(6): 514-518, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37451837

RESUMO

Adopting emerging microbiological methods is often desirable because it enables more advantageous, real-time monitoring practices. However, when the newer method measures contamination based on a different detection principle and provides results that are based on different units of measure, a paradigm shift is necessary. That shift can be one of the most difficult challenges in any such project and requires careful consideration. In this article, we explore the challenges presented by the bio-fluorescent particle counting (BFPC) technology, when considering that the traditional colony-forming unit (CFU) is the gold standard that any change is measured against. We examine why attempts to correlate newer units of measure used by biofluorescent particle counters, namely the auto-fluorescent units (AFUs), to the traditional CFUs are not necessarily appropriate. The article explores in depth why there is no consistent correlation factor between the two units of measure, and why that should not be a barrier to fully leveraging, implementing, and using such modern technologies in routine monitoring.


Assuntos
Técnicas Microbiológicas , Células-Tronco , Técnicas Microbiológicas/métodos , Contagem de Colônia Microbiana
9.
Diagn Microbiol Infect Dis ; 107(2): 116025, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37480620

RESUMO

The aim of this study was to comprehensively evaluate metagenomic next-generation sequencing (mNGS), Acid-fast bacillus stain (AFB), MGIT960 culture, polymerase-chain-reaction (PCR), and Xpert MTB/RIF in the diagnosis of tuberculous meningitis (TBM). A cohort of 280 patients who presented with suspected TBM (ie, headache or altered mental status with clinical signs of meningism) were analyzed. The sensitivities of the 5 assays for the diagnosis of TBM ranged from 10.0% to 70.0%. The AFB had the lowest sensitivity of 10.0% (0.5-45.9), while mNGS and PCR had the highest sensitivity, both at 70.0% (35.4-91.9). mNGS demonstrated a distinct advantage in identifying a wider array of pathogens, including viruses, in CSF samples. PCR was a cost-effective option with excellent sensitivity and specificity. However, no single method was statistically significantly better than any other in the diagnosis of TBM. New diagnostic techniques are urgently needed for the independent, rapid and accurate detection of Mycobacterium tuberculosis to guide the diagnosis of TBM.


Assuntos
Mycobacterium tuberculosis , Tuberculose Meníngea , Humanos , Tuberculose Meníngea/diagnóstico , Técnicas Microbiológicas , Mycobacterium tuberculosis/genética , Bioensaio , Sequenciamento de Nucleotídeos em Larga Escala
10.
Front Cell Infect Microbiol ; 13: 1153693, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37384222

RESUMO

Campylobacter spp. are considered the most frequent cause of acute gastroenteritis worldwide. However, outside high-income countries, its burden is poorly understood. Limited published data suggest that Campylobacter prevalence in low- and middle-income countries is high, but their reservoirs and age distribution are different. Culturing Campylobacter is expensive due to laboratory equipment and supplies needed to grow the bacterium (e.g., selective culture media, microaerophilic atmosphere, and a 42°C incubator). These requirements limit the diagnostic capacity of clinical laboratories in many resource-poor regions, leading to significant underdiagnosis and underreporting of isolation of the pathogen. CAMPYAIR, a newly developed selective differential medium, permits Campylobacter isolation without the need for microaerophilic incubation. The medium is supplemented with antibiotics to allow Campylobacter isolation in complex matrices such as human feces. The present study aims to evaluate the ability of the medium to recover Campylobacter from routine clinical samples. A total of 191 human stool samples were used to compare the ability of CAMPYAIR (aerobic incubation) and a commercial Campylobacter medium (CASA, microaerophilic incubation) to recover Campylobacter. All Campylobacter isolates were then identified by MALDI-TOF MS. CAMPYAIR showed sensitivity and specificity values of 87.5% (95% CI 47.4%-99.7%) and 100% (95% CI 98%-100%), respectively. The positive predictive value of CAMPYAIR was 100% and its negative predictive value was 99.5% (95% CI 96.7%-99.9%); Kappa Cohen coefficient was 0.93 (95% CI 0.79-1.0). The high diagnostic performance and low technical requirements of the CAMPYAIR medium could permit Campylobacter culture in countries with limited resources.


Assuntos
Infecções por Campylobacter , Campylobacter , Meios de Cultura , Técnicas Microbiológicas , Meios de Cultura/normas , Aerobiose , Campylobacter/classificação , Campylobacter/crescimento & desenvolvimento , Campylobacter/isolamento & purificação , Infecções por Campylobacter/diagnóstico , Infecções por Campylobacter/microbiologia , Fezes/microbiologia , Valor Preditivo dos Testes , Técnicas Microbiológicas/métodos , Técnicas Microbiológicas/normas
11.
J AOAC Int ; 106(6): 1564-1573, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37341625

RESUMO

OBJECTIVE: The present investigation studies the efficacy of an automated growth-based system for a quantitative determination of Candida albicans and Aspergillus brasiliensis in several personal care products. The main purpose of this validation study was to prove that the alternative method's entire performance is not inferior to the conventional pour-plate method for a quantitative determination of yeasts and molds. Thus, a performance equivalence was established in accordance with the United Stated Pharmacopeia (USP-NF) Validation of Alternative Microbiological Methods ˂1223˃. METHODS: C. albicans and A. brasiliensis were pooled to use as inoculum (equivalent to 1.0 × 108 CFU/mL) in the suitability of the method test. PCP's preservatives were chemically neutralized leading to the yeast and mold recovery by means of the alternative microbiological method (AMM) and the pour-plate method. A correlation curve was generated for each PCP by plotting DTs relative to the corresponding log CFU values. RESULTS: Thirty PCPs have been tested for quantification of yeasts and molds using an AMM. An equivalence of results was made through the construction of correlation curves that allowed the establishment of numerically equivalent results between the enumeration data from the reference method (CFU) and the alternative method (Detection times, DTs). Thus, following the guidelines of USP Ch.1223, essential validation parameters were tested, such as equivalence of results (Correlation coeficient, CC >0.95), linearity (R2 >0.9025), accuracy (% recovery >70%), operating range, precision (CV <35%), ruggedness (one-way ANOVA, P > 0.05), specificity, LOD, and LOQ. CONCLUSION: It was shown that all the test results obtained from the alternative method were in statistical agreement with the standard plate-count method (PCM). Thus, this new technology was found to meet all the validation criteria needed to be considered for an alternative method for yeast and mold quantification in the PCPs tested. HIGHLIGHTS: In accordance with the United Stated Pharmacopeia (USP-NF) Validation of Alternative Microbiological Methods ˂1223˃, the implementation of alternative methods can offer benefits in execution and automation while improving accuracy, sensitivity, and precision and reduce the microbiological process time compared to the traditional ones.


Assuntos
Fungos , Leveduras , Contagem de Colônia Microbiana , Técnicas Microbiológicas
12.
J Microbiol Methods ; 208: 106727, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37127093

RESUMO

A simple method for the automatic inoculation of broth culture tubes is described. An incubator is plugged into an electrical outlet timer. Heating of the incubator causes wax-like coconut oil to melt and allow an inoculum-coated bead to drop into sterile liquid medium.


Assuntos
Óleo de Coco , Técnicas Microbiológicas
13.
J Clin Microbiol ; 61(6): e0015423, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37154734

RESUMO

Diagnosis of bone and joint infections (BJI) relies on microbiological culture which has a long turnaround time and is challenging for certain bacterial species. Rapid molecular methods may alleviate these obstacles. Here, we investigate the diagnostic performance of IS-pro, a broad-scope molecular technique that can detect and identify most bacteria to the species level. IS-pro additionally informs on the amount of human DNA present in a sample, as a measure of leukocyte levels. This test can be performed in 4 h with standard laboratory equipment. Residual material of 591 synovial fluid samples derived from native and prosthetic joints from patients suspected of joint infections that were sent for routine diagnostics was collected and subjected to the IS-pro test. Bacterial species identification as well as bacterial load and human DNA load outcomes of IS-pro were compared to those of culture. At sample level, percent positive agreement (PPA) between IS-pro and culture was 90.6% (95% CI 85.7- to 94%) and negative percent agreement (NPA) was 87.7% (95% CI 84.1 to 90.6%). At species level PPA was 80% (95% CI 74.3 to 84.7%). IS-pro yielded 83 extra bacterial detections over culture for which we found supporting evidence for true positivity in 40% of the extra detections. Missed detections by IS-pro were mostly related to common skin species in low abundance. Bacterial and human DNA signals measured by IS-pro were comparable to bacterial loads and leukocyte counts reported by routine diagnostics. We conclude that IS-pro showed an excellent performance for fast diagnostics of bacterial BJI.


Assuntos
Artrite Infecciosa , Técnicas Microbiológicas , Infecções Relacionadas à Prótese , Humanos , Artrite Infecciosa/diagnóstico , Artrite Infecciosa/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/microbiologia , Testes de Diagnóstico Rápido/instrumentação , Testes de Diagnóstico Rápido/normas , Líquido Sinovial/citologia , Líquido Sinovial/microbiologia , Sensibilidade e Especificidade , DNA/genética , Técnicas Microbiológicas/instrumentação , Técnicas Microbiológicas/normas
14.
Microbiol Spectr ; 11(3): e0089723, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37162344

RESUMO

BD Phoenix CPO Detect panels can identify and classify carbapenemase-producing organisms (CPOs) simultaneously with antimicrobial susceptibility testing (AST) for Gram-negative bacteria. Detection and classification of carbapenemase producers were performed using the BD Phoenix CPO Detect panels NMIC/ID-441 for Enterobacterales, NMIC/ID-442 for nonfermenting bacteria, and NMIC-440 for both. The results were compared with those obtained using comparator methods. A total of 133 strains (32 Klebsiella pneumoniae, 37 Enterobacter cloacae complex, 33 Pseudomonas aeruginosa, and 31 Acinetobacter baumannii complex strains), including 60 carbapenemase producers (54 imipenemases [IMPs] and 6 OXA type), were analyzed. Using panels NMIC-440 and NMIC/ID-441 or NMIC/ID-442, all 54 IMP producers were accurately identified as CPOs (positive percent agreement [PPA], 100.0%; 54/54). Among the 54 IMP producers identified as CPOs using panels NMIC-440 and NMIC/ID-441, 12 and 14 Enterobacterales were not resistant to carbapenem, respectively. Among all 54 IMP producers, 48 (88.9%; 48/54) were correctly classified as Ambler class B using panel NMIC-440. Using panels NMIC-440 and NMIC/ID-442, all four OXA-23-like carbapenemase-producing A. baumannii complex strains (100.0%, 4/4) were correctly identified as CPOs, and three (75.0%, 3/4) were precisely classified as class D using panel NMIC-440. Both carbapenemase producers harboring the blaISAba1-OXA-51-like gene were incorrectly identified as non-CPOs using panels NMIC-440 and NMIC/ID-442. For detecting carbapenemase producers, the overall PPA and negative percent agreement (NPA) between panel NMIC-440 and the comparator methods were 96.7% (58/60) and 71.2% (52/73), respectively, and the PPA and NPA between panels NMIC/ID-441 or NMIC/ID-442 and the comparator methods were 96.7% (58/60) and 74.0% (54/73), respectively. BD Phoenix CPO Detect panels can successfully screen carbapenemase producers, particularly IMP producers, regardless of the presence of carbapenem resistance and can be beneficial in routine AST workflows. IMPORTANCE Simple and efficient screening methods of detecting carbapenemase producers are required. BD Phoenix CPO Detect panels effectively screened carbapenemase producers, particularly IMP producers, with a high overall PPA. As the panels enable automatic screening for carbapenemase producers simultaneously with AST, the workflow from AST to confirmatory testing for carbapenemase production can be shortened. In addition, because carbapenem resistance varies among carbapenemase producers, the BD Phoenix CPO Detect panels, which can screen carbapenemase producers regardless of carbapenem susceptibility, can contribute to the accurate detection of carbapenemase producers. Our results report that these panels can help streamline the AST workflow before confirmatory testing for carbapenemase production in routine microbiological tests.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Técnicas Microbiológicas , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Testes de Sensibilidade Microbiana , Enterobacteriáceas Resistentes a Carbapenêmicos/classificação , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Técnicas Microbiológicas/métodos , Técnicas Microbiológicas/normas , Reprodutibilidade dos Testes , Especificidade da Espécie
15.
Braz J Microbiol ; 54(2): 761-768, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37160839

RESUMO

To maintain asepsis in production environments, contamination must be constantly controlled. To this end, microbiological monitoring is constantly used with the objective of evaluating the incidence of microorganisms prevalent in the sampling of air, surface, and people, in the area of an environment considered aseptic, isolated, and identified using the rapid and automated phenotypic microbiological methodology, highlighting the MALDI-TOF mass spectrometry analysis technique (MS), being identified at the level of genus and/or species. For that purpose, microbiological control of environmental monitoring of environments considered aseptic in a pharmaceutical industry was conducted for 12 months. The isolated microorganisms were identified using the mass spectrometry identification method (MALDI-TOF). In area classification A, the most prevalent microorganisms were bacteria in the sampling person. The microbial population was composed of bacteria of the genus Micrococcus sp. and Staphylococcus sp. Based on the results, it is possible to observe that in an environment where the process requires human operations, possible microbial contamination is inevitable and requires the identification of microorganisms at least at the level of species and/or genus. The microorganisms identified and found in the sampling of the aseptic environment must be evaluated with frequency to ensure that the productive environment guarantees the quality of the product produced.


Assuntos
Bactérias , Staphylococcus , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Técnicas Microbiológicas/métodos
16.
Nucleic Acids Res ; 51(W1): W310-W318, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37166960

RESUMO

Microbiome studies have become routine in biomedical, agricultural and environmental sciences with diverse aims, including diversity profiling, functional characterization, and translational applications. The resulting complex, often multi-omics datasets demand powerful, yet user-friendly bioinformatics tools to reveal key patterns, important biomarkers, and potential activities. Here we introduce MicrobiomeAnalyst 2.0 to support comprehensive statistics, visualization, functional interpretation, and integrative analysis of data outputs commonly generated from microbiome studies. Compared to the previous version, MicrobiomeAnalyst 2.0 features three new modules: (i) a Raw Data Processing module for amplicon data processing and taxonomy annotation that connects directly with the Marker Data Profiling module for downstream statistical analysis; (ii) a Microbiome Metabolomics Profiling module to help dissect associations between community compositions and metabolic activities through joint analysis of paired microbiome and metabolomics datasets; and (iii) a Statistical Meta-Analysis module to help identify consistent signatures by integrating datasets across multiple studies. Other important improvements include added support for multi-factor differential analysis and interactive visualizations for popular graphical outputs, updated methods for functional prediction and correlation analysis, and expanded taxon set libraries based on the latest literature. These new features are demonstrated using a multi-omics dataset from a recent type 1 diabetes study. MicrobiomeAnalyst 2.0 is freely available at microbiomeanalyst.ca.


Assuntos
Biologia Computacional , Técnicas Microbiológicas , Microbiota , Biomarcadores , Biologia Computacional/métodos , Metabolômica/métodos , Técnicas Microbiológicas/instrumentação , Técnicas Microbiológicas/métodos , Internet , Interface Usuário-Computador
17.
Curr Pharm Des ; 29(15): 1166-1172, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37190804

RESUMO

Moxifloxacin (MOX) is a fourth-generation fluoroquinolone used in the form of tablets, infusion solutions and ophthalmic solutions. It does not have a physical-chemical or microbiological analytical method described in an official compendium. However, the literature shows some analysis methods for pharmaceuticals and biological matrices. In this context, the objective is to show the analytical methods present in the literature for the investigation of MOX by physical-chemical and microbiological techniques, as well as discussing them according to the requirements of current pharmaceutical analyses and green analytical chemistry. Among the physical-chemical methods present in the literature for MOX evaluation, 33% are HPLC, 21% are UV-Vis and 17% are capillary electrophoresis. On the other hand, among the microbiological methods, all of them are based on diffusion in agar. There is still scope in the literature to incorporate new and improved analytical methods for MOX evaluation, which adopt the concepts of green and sustainable analytical chemistry, either by using less (or not using) toxic organic solvents, reducing waste generation or even reducing the analysis time according to the intended objectives.


Assuntos
Técnicas Microbiológicas , Humanos , Moxifloxacina , Cromatografia Líquida de Alta Pressão
18.
Indian J Ophthalmol ; 71(5): 1698-1705, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37203021

RESUMO

Ocular microbiology deals with miniscule samples from ocular infections, which are difficult to collect, process, and analyze, necessitating special skills, and the knowledge of troubleshooting errors to reach a specific diagnosis. In this article, we highlight several practical points in ocular microbiology, common mistakes, and various approaches to resolve them. We have covered sample collection from different ocular compartments, processing for smear preparation and culture, transport of samples, staining and reagents issues, artifacts and contaminants, and interpretation of in-vitro antimicrobial susceptibility testing reports. This review aims to help both ophthalmologists and microbiologists in making the practice of ocular microbiology and the interpretation of reports more reliable, hassle-free, and precise.


Assuntos
Infecções Oculares , Manejo de Espécimes , Humanos , Infecções Oculares/diagnóstico , Infecções Oculares/microbiologia , Técnicas Microbiológicas
19.
Biosens Bioelectron ; 231: 115284, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37031508

RESUMO

Bacterial spores are problematic in agriculture, the food industry, and healthcare, with the fallout costs from spore-related contamination being very high. Spores are difficult to detect since they are resistant to many of the bacterial disruption techniques used to bring out the biomarkers necessary for detection. Because of this, effective and practical spore disruption methods are desirable. In this study, we demonstrate the efficiency of a compact microfluidic lab-on-chip built around a coplanar waveguide (CPW) operating at 2.45 GHz. We show that the CPW generates an electric field hotspot of ∼10 kV/m, comparable to that of a commercial microwave oven, while using only 1.2 W of input power and thus resulting in negligible sample heating. Spores passing through the microfluidic channel are disrupted by the electric field and release calcium dipicolinic acid (CaDPA), a biomarker molecule present alongside DNA in the spore core. We show that it is possible to detect this disruption in a bulk spore suspension using fluorescence spectroscopy. We then use laser tweezers Raman spectroscopy (LTRS) to show the loss of CaDPA on an individual spore level and that the loss increases with irradiation power. Only 22% of the spores contain CaDPA after exposure to 1.2 W input power, compared to 71% of the untreated control spores. Additionally, spores exposed to microwaves appear visibly disrupted when imaged using scanning electron microscopy (SEM). Overall, this study shows the advantages of using a CPW for disrupting spores for biomarker release and detection.


Assuntos
Dispositivos Lab-On-A-Chip , Técnicas Microbiológicas , Micro-Ondas , Esporos Bacterianos , Biomarcadores/análise , Estimulação Elétrica , Técnicas Microbiológicas/instrumentação , Técnicas Microbiológicas/métodos , Microscopia Eletrônica de Varredura , Pinças Ópticas , Espectrometria de Fluorescência , Análise Espectral Raman , Esporos Bacterianos/química , Esporos Bacterianos/metabolismo , Esporos Bacterianos/efeitos da radiação , Esporos Bacterianos/ultraestrutura
20.
PDA J Pharm Sci Technol ; 77(4): 268-280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37085183

RESUMO

Alternative and rapid microbiological methods can be effective replacements for more traditional plating approaches for ensuring quality and safety in the pharmaceutical industry. This article compares the efficacy of the Soleris automated method and the traditional plate-count method for the quantitative detection of yeasts and molds at three different microbial bioburden levels. Validation testing was carried out using an antacid oral suspension (aluminum hydroxide 4% + magnesium hydroxide 4% + simethicone 0.4%). Equivalence of data between detection time and colony-forming units was established for both the alternative and the conventional methodologies. Using probability of detection, linear Poisson regression, Fisher's test, and multifactorial analysis of variance (ANOVA), all results from the rapid method were shown to be in statistical agreement with the those of the reference plating procedures. The limits of detection and quantification were statistically similar for both methods (Fisher's exact test, P > 0.05), showing that the alternative method is not inferior in performance to the reference method. Essential validation parameters such as precision (standard deviation <5, coefficient of variance <35%), accuracy (>70%), linearity (R2 >0.9025), ruggedness (ANOVA, P < 0.05), operative range, and specificity were determined. It was shown that all the test results obtained using the alternative method were in statistical agreement with the those of the standard plate-count method. Thus, this new technology was found to meet all the validation criteria needed to be considered as an alternative method for yeast and mold quantification in the antacid oral suspension tested. However, taking into account that the present validation was carried out utilizing A. brasiliensis and C. albicans as suitable models for yeasts and molds and with an antacid oral suspension as a pharmaceutical matrix, further investigation will be required to qualify Soleris technology for other environmental isolates and recovery of these isolates from production batches.


Assuntos
Antiácidos , Leveduras , Contagem de Colônia Microbiana , Fungos , Técnicas Microbiológicas/métodos
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