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1.
BMC Infect Dis ; 20(1): 825, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33176716

RESUMO

BACKGROUND: Light microscopy is often used for malaria diagnosis in the field. However, it is time-consuming and quality of the results depends heavily on the skill of microscopists. Automating malaria light microscopy is a promising solution, but it still remains a challenge and an active area of research. Current tools are often expensive and involve sophisticated hardware components, which makes it hard to deploy them in resource-limited areas. RESULTS: We designed an Android mobile application called Malaria Screener, which makes smartphones an affordable yet effective solution for automated malaria light microscopy. The mobile app utilizes high-resolution cameras and computing power of modern smartphones to screen both thin and thick blood smear images for P. falciparum parasites. Malaria Screener combines image acquisition, smear image analysis, and result visualization in its slide screening process, and is equipped with a database to provide easy access to the acquired data. CONCLUSION: Malaria Screener makes the screening process faster, more consistent, and less dependent on human expertise. The app is modular, allowing other research groups to integrate their methods and models for image processing and machine learning, while acquiring and analyzing their data.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Malária Falciparum/diagnóstico por imagem , Programas de Rastreamento/métodos , Microscopia/métodos , Plasmodium falciparum/isolamento & purificação , Smartphone , Confiabilidade dos Dados , Humanos , Aprendizado de Máquina , Malária Falciparum/parasitologia , Sensibilidade e Especificidade , Software
2.
BMC Infect Dis ; 20(1): 803, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33121458

RESUMO

BACKGROUND: Soil-transmitted helminths are more prevalent in tropics and sub-tropics including Ethiopia. Despite their high prevalence, direct saline microscopy with its low sensitivity has been used as a diagnostic method in almost all health facilities in Ethiopia. Alternative diagnostic methods which have higher sensitivity are not yet implemented. Therefore, this study aimed to compare and evaluate the performance of diagnostic methods for soil transmitted helminths. METHODS: A cross-sectional study among 520 school children was conducted from October to December, 2019 in Amhara National Regional State. The study participants were selected using systematic random sampling technique. Stool samples were processed via formol ether concentration, Kato-Katz, spontaneous tube sedimentation and agar plate culture techniques. Data was entered into Epi-data version 3.1 and analysis was done using SPSS version 20.0. The sensitivity, specificity, and negative predictive value were calculated against the combined result. Strength of agreement of the diagnostic methods was determined by Kappa value. RESULTS: The Overall prevalence of soil transmitted helminths was 40.8% using combination of methods. The prevalence 24.4, 22.5, and 32.4%, respectively was recorded by using formol ether concentration, Kato-Katz and spontaneous tube sedimentation. The highest prevalence of hookworm (29.2%) was detected by the agar plate culture. The sensitivity and negative predictive value of formol ether concentration were 57.9 and 78.4%, for Kato-Katz thick smear 55.2 and 76.4%, for spontaneous tube sedimentation were 79.2 and 87.5% to soil transmitted helminths detection, respectively. The sensitivity and negative predictive value of agar plate culture to hookworm detection were 86.4 and 93.5%, respectively. CONCLUSION: Spontaneous tube sedimentation shows higher sensitivity in the detection of soil transmitted helminth infections. Agar plate culture method also indicated better performance for hookworm detection than other methods. Therefore, the employment of spontaneous tube sedimentation technique for routine laboratory and agar plate culture for research purposes will significantly aid in accurate diagnosis of parasitic infections.


Assuntos
Ancylostomatoidea/isolamento & purificação , Testes Diagnósticos de Rotina/métodos , Infecções por Uncinaria/diagnóstico , Infecções por Uncinaria/transmissão , Solo/parasitologia , Adolescente , Animais , Criança , Estudos Transversais , Etiópia/epidemiologia , Fezes/parasitologia , Feminino , Formaldeído , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/parasitologia , Humanos , Masculino , Microscopia/métodos , Prevalência , Sensibilidade e Especificidade
3.
Ann Biol Clin (Paris) ; 78(5): 519-526, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33026347

RESUMO

Digital morphology hematology analyzers are becoming more prevalent in laboratories Aims: investigate practices and assess the benefits and limits of digital automated microscopy in hematology. METHODS: questionnaire sent by e-mail in 2018 to French public and private laboratories. RESULTS: out of 118 responses (56 private, 62 public), 117 participants had a CellaVision® microscope, 1 had a West Medica®. Practices were sometimes different, especially in the choice of smears to be digitized or for quality controls (16.1% had internal quality controls, 48.3% external quality controls); 62.1% never used the red blood cell (RBC) characterization tool; the number of cells counted varied from 100 to 400. The study reported a high rate of agreement for these benefits: traceability (95.7%), staff training (94.1%), eye strain (91.4%), risk of error (87.2%), time saving (83.6%). Among the disadvantages, apart from the inadequate search for platelets clumps (93.2%), the agreement rates were often lower: adaptation to digital images (61.2%), difficult assessment of atypical morphologies (49.6%) or RBC morphology (49.6%). CONCLUSION: despite well-established benefits, standardization of practices and technical improvement are still needed.


Assuntos
Automação Laboratorial , Testes Hematológicos/instrumentação , Hematologia/instrumentação , Processamento de Imagem Assistida por Computador , Microscopia/instrumentação , Atitude do Pessoal de Saúde , Automação Laboratorial/instrumentação , Automação Laboratorial/métodos , Automação Laboratorial/estatística & dados numéricos , Computadores , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Testes Diagnósticos de Rotina/estatística & dados numéricos , Testes Diagnósticos de Rotina/tendências , França/epidemiologia , Testes Hematológicos/métodos , Testes Hematológicos/estatística & dados numéricos , Testes Hematológicos/tendências , Hematologia/métodos , Hematologia/estatística & dados numéricos , Hematologia/tendências , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Processamento de Imagem Assistida por Computador/tendências , Satisfação no Emprego , Microscopia/métodos , Microscopia/estatística & dados numéricos , Microscopia/tendências , Prática Profissional/estatística & dados numéricos , Prática Profissional/tendências , Controle de Qualidade , Inquéritos e Questionários
4.
PLoS One ; 15(10): e0239342, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33027314

RESUMO

INTRODUCTION: Tuberculosis disease is the leading cause of death worldwide along with HIV/AIDS. Sputum smear microscopy plays an essential role for initial TB diagnosis and treatment follow up. But, misdiagnosis of sputum smear microscopy revealed a high economical crisis and missing of active TB cases. This study was aimed to determine blinded rechecking of sputum smear microscopy performance in public health facilities in Tigray region, Northern Ethiopia. MATERIALS AND METHODS: A cross sectional retrospective study was conducted from January, 2017 to December, 2018 year. Data was collected retrospectively using electronic and paper based in Tigray health research institute. The data was analyzed using the SPSS version 25 software. The sensitivity, specificity, positive predictive value, and negative predictive value of the smear readings were calculated using 2X2 contingency table. The reading agreement between the microscopic center and reference center was determined using kappa statistics. RESULTS: A total of 23,456 blinded rechecked smear results were reviewed. In average, the performances of sputum smear quality were 61%, 68%, 64%, 66%, 62% and 75% for specimen quality, staining quality, smear size, smear thickness, smear evenness and smear cleanliness respectively. Of the total error (0.48%) reported, 0.25%, 0.19% and 0.085% were false positive, false negative and quantification errors respectively. The concordance rate of health facilities for smear reading was increased to 90% by the end of 2018. Overall, the sensitivity, specificity, PPV, and NPV of the smear readings were 95%, 99.7%, 93% and 99.8% respectively. Likewise, the smear reading agreement was also perfect with kappa value, 0.87. CONCLUSION: The overall performance of public health facilities for blinded rechecking of smear microscopy was satisfactory. But, the high false positive and false negative errors found calls for continuous evaluation and monitoring of the health facilities by reference center.


Assuntos
Microscopia/métodos , Escarro/microbiologia , Tuberculose/diagnóstico , Estudos Transversais , Etiópia , Reações Falso-Negativas , Humanos , Microscopia/normas , Controle de Qualidade , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Pathol Res Pract ; 216(11): 153196, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32927307

RESUMO

We have witnessed successive stages since the Seventies in the advancements towards digital pathology. We agree with Dr Pallua et al on the tremendous changes that are taking place in pathology, all leading toward greater role of digitalization in the field of pathology, both in terms of consultation and teaching. In particular, distance teaching using digital pathology will grow into a mainstream mode of pathology teaching, something that has been reinforced by COVID-19.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/patologia , Processamento de Imagem Assistida por Computador , Patologia Clínica , Pneumonia Viral/patologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Microscopia/métodos , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia
6.
PLoS Comput Biol ; 16(9): e1008193, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32925919

RESUMO

Segmenting cell nuclei within microscopy images is a ubiquitous task in biological research and clinical applications. Unfortunately, segmenting low-contrast overlapping objects that may be tightly packed is a major bottleneck in standard deep learning-based models. We report a Nuclear Segmentation Tool (NuSeT) based on deep learning that accurately segments nuclei across multiple types of fluorescence imaging data. Using a hybrid network consisting of U-Net and Region Proposal Networks (RPN), followed by a watershed step, we have achieved superior performance in detecting and delineating nuclear boundaries in 2D and 3D images of varying complexities. By using foreground normalization and additional training on synthetic images containing non-cellular artifacts, NuSeT improves nuclear detection and reduces false positives. NuSeT addresses common challenges in nuclear segmentation such as variability in nuclear signal and shape, limited training sample size, and sample preparation artifacts. Compared to other segmentation models, NuSeT consistently fares better in generating accurate segmentation masks and assigning boundaries for touching nuclei.


Assuntos
Núcleo Celular/fisiologia , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Microscopia/métodos , Algoritmos , Artefatos , Biologia Computacional , Células HeLa , Humanos , Software
7.
Nat Commun ; 11(1): 4830, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973134

RESUMO

Non-invasively probing metabolites within single live cells is highly desired but challenging. Here we utilize Raman spectro-microscopy for spatial mapping of metabolites within single cells, with the specific goal of identifying druggable metabolic susceptibilities from a series of patient-derived melanoma cell lines. Each cell line represents a different characteristic level of cancer cell de-differentiation. First, with Raman spectroscopy, followed by stimulated Raman scattering (SRS) microscopy and transcriptomics analysis, we identify the fatty acid synthesis pathway as a druggable susceptibility for differentiated melanocytic cells. We then utilize hyperspectral-SRS imaging of intracellular lipid droplets to identify a previously unknown susceptibility of lipid mono-unsaturation within de-differentiated mesenchymal cells with innate resistance to BRAF inhibition. Drugging this target leads to cellular apoptosis accompanied by the formation of phase-separated intracellular membrane domains. The integration of subcellular Raman spectro-microscopy with lipidomics and transcriptomics suggests possible lipid regulatory mechanisms underlying this pharmacological treatment. Our method should provide a general approach in spatially-resolved single cell metabolomics studies.


Assuntos
Melanoma/metabolismo , Metabolômica/métodos , Microscopia/métodos , Análise Espectral Raman/métodos , Apoptose , Linhagem Celular Tumoral , Ácidos Graxos/metabolismo , Humanos , Gotículas Lipídicas , Metabolismo dos Lipídeos , Lipidômica , Lipídeos , Ácido Oleico , Estearoil-CoA Dessaturase/metabolismo , Transcriptoma
8.
PLoS One ; 15(9): e0235727, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946443

RESUMO

The objective of this study was to develop a computer-aided method to quantify the obvious degree of growth ring boundaries of softwood species, based on data analysis with some image processing technologies. For this purpose, a 5× magnified cross-section color micro-image of softwood was cropped into 20 sub-images, and then every image was binarized as a gray image according to an automatic threshold value. After that, the number of black pixels in the gray image was counted row by row and the number of black pixels was binarized to 0 or 100. Finally, a transition band from earlywood to latewood on the sub-image was identified. If everything goes as planned, the growth ring boundaries of the sub-image would be distinct. Otherwise would be indistinct or absent. If more than 50% sub-images are distinct, with the majority voting method, the growth ring boundaries of softwood would be distinct, otherwise would be indistinct or absent. The proposed method has been visualized as a growth-ring-boundary detecting system based on the .NET Framework. A sample of 100 micro-images (see S1 Fig via https://github.com/senly2019/Lin-Qizhao/) of softwood cross-sections were selected for evaluation purposes. In short, this detecting system computes the obvious degree of growth ring boundaries of softwood species by image processing involving image importing, image cropping, image reading, image grayscale, image binarization, data analysis. The results showed that the method used avoided mistakes made by the manual comparison method of identifying the presence of growth ring boundaries, and it has a high accuracy of 98%.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Árvores/crescimento & desenvolvimento , Madeira/crescimento & desenvolvimento , Cor , Microscopia/métodos
9.
Nat Commun ; 11(1): 4632, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934230

RESUMO

Mapping neuroanatomy is a foundational goal towards understanding brain function. Electron microscopy (EM) has been the gold standard for connectivity analysis because nanoscale resolution is necessary to unambiguously resolve synapses. However, molecular information that specifies cell types is often lost in EM reconstructions. To address this, we devise a light microscopy approach for connectivity analysis of defined cell types called spectral connectomics. We combine multicolor labeling (Brainbow) of neurons with multi-round immunostaining Expansion Microscopy (miriEx) to simultaneously interrogate morphology, molecular markers, and connectivity in the same brain section. We apply this strategy to directly link inhibitory neuron cell types with their morphologies. Furthermore, we show that correlative Brainbow and endogenous synaptic machinery immunostaining can define putative synaptic connections between neurons, as well as map putative inhibitory and excitatory inputs. We envision that spectral connectomics can be applied routinely in neurobiology labs to gain insights into normal and pathophysiological neuroanatomy.


Assuntos
Conectoma/métodos , Microscopia/métodos , Neurônios/fisiologia , Animais , Encéfalo/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Neuroanatomia , Neurônios/química , Sinapses/química , Sinapses/fisiologia
10.
PLoS Pathog ; 16(9): e1008738, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32946515

RESUMO

Microsporidia, a divergent group of single-celled eukaryotic parasites, harness a specialized harpoon-like invasion apparatus called the polar tube (PT) to gain entry into host cells. The PT is tightly coiled within the transmissible extracellular spore, and is about 20 times the length of the spore. Once triggered, the PT is rapidly ejected and is thought to penetrate the host cell, acting as a conduit for the transfer of infectious cargo into the host. The organization of this specialized infection apparatus in the spore, how it is deployed, and how the nucleus and other large cargo are transported through the narrow PT are not well understood. Here we use serial block-face scanning electron microscopy to reveal the 3-dimensional architecture of the PT and its relative spatial orientation to other organelles within the spore. Using high-speed optical microscopy, we also capture and quantify the entire PT germination process of three human-infecting microsporidian species in vitro: Anncaliia algerae, Encephalitozoon hellem and E. intestinalis. Our results show that the emerging PT experiences very high accelerating forces to reach velocities exceeding 300 µm⋅s-1, and that firing kinetics differ markedly between species. Live-cell imaging reveals that the nucleus, which is at least 7 times larger than the diameter of the PT, undergoes extreme deformation to fit through the narrow tube, and moves at speeds comparable to PT extension. Our study sheds new light on the 3-dimensional organization, dynamics, and mechanism of PT extrusion, and shows how infectious cargo moves through the tube to initiate infection.


Assuntos
Microscopia/métodos , Microsporídios/patogenicidade , Organelas/imunologia , Organelas/ultraestrutura , Esporos Fúngicos/imunologia , Esporos Fúngicos/ultraestrutura , Proteínas Fúngicas/metabolismo , Microsporídios/imunologia , Microsporídios/ultraestrutura , Esporos Fúngicos/crescimento & desenvolvimento
11.
Nat Commun ; 11(1): 3851, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737314

RESUMO

Intravascular imaging has emerged as a valuable tool for the treatment of coronary and peripheral artery disease; however, no solution is available for safe and reliable use in the tortuous vascular anatomy of the brain. Endovascular treatment of stroke is delivered under image guidance with insufficient resolution to adequately assess underlying arterial pathology and therapeutic devices. High-resolution imaging, enabling surgeons to visualize cerebral arteries' microstructure and micron-level features of neurovascular devices, would have a profound impact in the research, diagnosis, and treatment of cerebrovascular diseases. Here, we present a neurovascular high-frequency optical coherence tomography (HF-OCT) system, including an imaging console and an endoscopic probe designed to rapidly acquire volumetric microscopy data at a resolution approaching 10 microns in tortuous cerebrovascular anatomies. Using a combination of in vitro, ex vivo, and in vivo models, the feasibility of HF-OCT for cerebrovascular imaging was demonstrated.


Assuntos
Artéria Basilar/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Artérias Cerebrais/diagnóstico por imagem , Microscopia/métodos , Tomografia de Coerência Óptica/métodos , Artéria Vertebral/diagnóstico por imagem , Angiografia/instrumentação , Angiografia/métodos , Animais , Cadáver , Circulação Cerebrovascular/fisiologia , Humanos , Microscopia/instrumentação , Suínos , Tomografia de Coerência Óptica/instrumentação
12.
J Steroid Biochem Mol Biol ; 202: 105727, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32682060

RESUMO

Systematic studies on the influence of selected ring-oxidized (7α-hydroxycholesterol, 7α-OH; 7ß-hydroxycholesterol, 7ß-OH; 7-ketocholesterol, 7-K) and chain-oxidized (25-OH) sterols on lipid layer of myelin were performed. Myelin sheath was modeled as five-component Langmuir monolayer (Chol:PE:SM:PS:PC 50:20:12:9:9). Particular oxysterols have been incorporated into the model myelin sheath by replacing cholesterol totally or partially (1:1). The effect of oxysterol incorporation was characterized with surface pressure and electric surface potential - area isotherms and visualized with Brewster angle microscopy (BAM) and atomic force microscopy (AFM). It has been noticed that model myelin loses its homogeneous structure (due to the appearance of domains) at physiological bilayer conditions (30-35 mN/m). In the presence of oxysterols, the fluidity of myelin model increases and the organization of lipids is altered, which is reflected in the decrease of electric surface potential changes (ΔV). The strongest myelin/oxysterol interactions have been observed for 7-K and 25-OH, being the most cytotoxic oxysterols found in biological tests.


Assuntos
Modelos Biológicos , Bainha de Mielina/fisiologia , Oxisteróis , Microscopia/métodos , Doenças Neurodegenerativas , Propriedades de Superfície
13.
Nat Protoc ; 15(8): 2611-2644, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32632318

RESUMO

While a host of molecular techniques are utilized by evolutionary developmental (evo-devo) biologists, tools for quantitative evaluation of morphology are still largely underappreciated, especially in studies on microscopic animals. Here, we provide a standardized protocol for geometric morphometric analyses of 2D landmark data sets using a combination of the geomorph and Morpho R packages. Furthermore, we integrate clustering approaches to identify group structures within such datasets. We demonstrate our protocol by performing exemplary analyses on stomatal shapes in the model nematodes Caenorhabditis and Pristionchus. Image acquisition for 80 worms takes 3-4 d, while the entire data analysis requires 10-30 min. In theory, this approach is adaptable to all microscopic model organisms to facilitate a thorough quantification of shape differences within and across species, adding to the methodological toolkit of evo-devo studies on morphological evolution and novelty.


Assuntos
Caenorhabditis/citologia , Microscopia/métodos , Animais , Evolução Biológica , Reprodutibilidade dos Testes
15.
Int J Infect Dis ; 98: 408-419, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32659450

RESUMO

BACKGROUND: Diagnosis is a challenging issue for eliminating malaria. Loop-mediated isothermal amplification (LAMP) could be an alternative to conventional methods. This study aimed to evaluate the diagnostic accuracy of LAMP for malaria compared with microscopy, polymerase chain reaction (PCR) and rapid diagnostic tests (RDTs). METHODS AND DESIGN: MEDLINE, Web of Science and Scopus were searched from inception to 1 July 2019. Prospective and retrospective, randomised and non-randomised, mono-center and multi-center studies, including symptomatic or asymptomatic patients, that reported one LAMP method and one comparator (microscopy, RDT or PCR) were included. PROSPERO registration number: CRD42017075186. RESULTS: Sixty-six studies published between 2006 and 2019 were included, leading to the analysis of 30,641 LAMP tests. The pooled sensitivity of LAMP remained between 96% and 98%, whichever the comparator. The pooled specificity of LAMP was around 95%, but was a little higher if the best PCR studies were considered. The AUC was found to be >0.98, whichever the subgroup of studies was considered. Diagnostic odds ratio (DOR) was found to be around 1000 for all subgroups, except for Plasmodium vivax. CONCLUSION: This meta-analysis confirmed that the LAMP method is robust for diagnosing malaria, both in symptomatic and asymptomatic people. Thus, the impact of LAMP for controlling malaria is expected to be important.


Assuntos
Testes Diagnósticos de Rotina/normas , Malária/diagnóstico , Microscopia/normas , Técnicas de Amplificação de Ácido Nucleico/normas , Plasmodium/isolamento & purificação , Reação em Cadeia da Polimerase/normas , Testes Diagnósticos de Rotina/métodos , Humanos , Malária/parasitologia , Microscopia/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Plasmodium/classificação , Plasmodium/genética , Plasmodium/fisiologia , Reação em Cadeia da Polimerase/métodos , Estudos Prospectivos , Estudos Retrospectivos , Sensibilidade e Especificidade
16.
BMC Infect Dis ; 20(1): 548, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727388

RESUMO

BACKGROUND: Bacteriological confirmation (BC) proportion among notified pulmonary TB patients in China is among the lowest in the world. This study was to understand the yield of BC using different testing strategies and patient-level factors associated with BC among pulmonary TB patients in Tianjin, China during 2017-2018. METHODS: A retrospective study was conducted, enrolling pulmonary TB patients reported to National TB Information Management System (TBIMS) in Tianjin during 2017-2018. BC was defined as a positive result by any of the followings: smear microscopy, culture, or nucleic acid amplification test. Individual characteristics were compared between patients with positive and negative bacteriological results using contingency tables and χ2 test. Multivariable logistic regression was applied to analyze factors associated with BC, calculating adjusted odds ratios (aOR) and 95% confidence intervals (CI) (α = 0.05). RESULTS: Of 6364 reported patients, 4181 (65.7%) were bacteriologically confirmed. Positivity proportion was 43.1% (2746/6364) for smear microscopy, 57.7% (3380/5853) for culture, 61.7% (1608/2605) for Xpert® MTB/RIF assay (Xpert) and 73.4% (1824/2484) for combination of the three. The unemployed (aOR = 1.5, 95% CI: 1.0-2.2) and farmers (aOR = 1.7, 95% CI: 1.1-2.8) compared with students; diagnosis by inpatient hospitals compared with TB clinics (aOR = 3.4, 95% CI: 2.6-4.4); having symptoms for ≥2 weeks (aOR = 1.4, 95% CI: 1.1-1.8); cough (aOR = 2.2, 95% CI: 1.8-2.8); blood sputum (aOR = 1.5, 95% CI: 1.0-2.2); cavitation on chest X-ray (aOR = 3.3, 95% CI: 2.5-4.3); bilateral lung lobes affected (aOR = 1.7, 95% CI: 1.4-2.2) were factors associated with BC. CONCLUSIONS: Combination test was an effective way to improve BC among pulmonary TB patients. Being unemployed, farmers, having prolonged symptoms, and more severe in TB condition were factors associated with BC. We recommend combination of tests to improve BC for pulmonary TB patients, especially who are in early stage of the disease or with conditions tend to be bacteriologically negative.


Assuntos
Microscopia/métodos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologia , Adulto , Idoso , China/epidemiologia , Fazendeiros , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Escarro/microbiologia , Tuberculose Pulmonar/microbiologia , Desemprego , Adulto Jovem
17.
PLoS Negl Trop Dis ; 14(7): e0008296, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32614828

RESUMO

The World Health Organization (WHO) has defined moderate-to-heavy intensity (M&HI) infections with soil-transmitted helminths (Ascaris lumbricoides, Trichuris trichiura and the two hookworms, Ancylostoma duodenale and Necator americanus) based on specific values of eggs per gram of stool, as measured by the Kato-Katz method. There are a variety of novel microscopy and DNA-based methods but it remains unclear whether applying current WHO thresholds on to these methods allows for a reliable classification of M&HI infections. We evaluated both WHO and method-specific thresholds for classifying the M&HI infections for novel microscopic (FECPAKG2, McMaster and Mini-FLOTAC) and DNA-based (qPCR) diagnostic methods. For this, we determined method-specific thresholds that best classified M&HI infections (defined by Kato-Katz and WHO thresholds; reference method) in two multi-country drug efficacy studies. Subsequently, we verified whether applying these method-specific thresholds improved the agreement in classifying M&HI infections compared to the reference method. When we applied the WHO thresholds, the new microscopic methods mainly misclassified M&HI as low intensity, and to a lesser extent low intensity infection as M&HI. For FECPAKG2, applying the method-specific thresholds significantly improved the agreement for Ascaris (moderate → substantial), Trichuris and hookworms (fair → moderate). For Mini-FLOTAC, a significantly improved agreement was observed for hookworms only (fair → moderate). For the other STHs, the agreement was almost perfect and remained unchanged. For McMaster, the method-specific thresholds revealed a fair to a substantial agreement but did not significantly improve the agreement. For qPCR, the method-specific thresholds based on genome equivalents per ml of DNA moderately agreed with the reference method for hookworm and Trichuris infections. For Ascaris, there was a substantial agreement. We defined method-specific thresholds that improved the classification of M&HI infections. Validation studies are required before they can be recommended for general use in assessing M&HI infections in programmatic settings.


Assuntos
Helmintíase/classificação , Microscopia/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Solo/parasitologia , Helmintíase/diagnóstico , Helmintíase/transmissão , Humanos , Organização Mundial da Saúde
18.
Nat Cell Biol ; 22(8): 1011-1023, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32719553

RESUMO

Detection and conversion of mechanical forces into biochemical signals controls cell functions during physiological and pathological processes. Mechanosensing is based on protein deformations and reorganizations, yet the molecular mechanisms are still unclear. Using a cell-stretching device compatible with super-resolution microscopy and single-protein tracking, we explored the nanoscale deformations and reorganizations of individual proteins inside mechanosensitive structures. We achieved super-resolution microscopy after live stretching on intermediate filaments, microtubules and integrin adhesions. Simultaneous single-protein tracking and stretching showed that while integrins followed the elastic deformation of the substrate, actin filaments and talin also displayed lagged and transient inelastic responses associated with active acto-myosin remodelling and talin deformations. Capturing acute reorganizations of single molecules during stretching showed that force-dependent vinculin recruitment is delayed and depends on the maturation of integrin adhesions. Thus, cells respond to external forces by amplifying transiently and locally cytoskeleton displacements, enabling protein deformation and recruitment in mechanosensitive structures.


Assuntos
Actinas/fisiologia , Forma Celular , Animais , Fenômenos Biomecânicos , Células Cultivadas , Técnicas Citológicas , Humanos , Integrinas/metabolismo , Camundongos , Microscopia/métodos , Nanoestruturas , Dobramento de Proteína , Transporte Proteico , Talina/metabolismo , Vinculina/metabolismo
19.
PLoS Comput Biol ; 16(6): e1007902, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32603371

RESUMO

We present the software platform 2CALM that allows for a comparative analysis of 3D localisation microscopy data representing protein distributions in two biological samples. The in-depth statistical analysis reveals differences between samples at the nanoscopic level using parameters such as cluster-density and -curvature. An automatic classification system combines multiplex and multi-level statistical approaches into one comprehensive parameter for similarity testing of the compared samples. We demonstrated the biological importance of 2CALM, comparing the protein distributions of CD41 and CD62p on activated platelets in a 3D artificial clot. Additionally, using 2CALM, we quantified the impact of the inflammatory cytokine interleukin-1ß on platelet activation in clots. The platform is applicable to any other cell type and biological system and can provide new insights into biological and medical applications.


Assuntos
Plaquetas/metabolismo , Proteínas de Membrana/metabolismo , Microscopia/métodos , Modelos Biológicos , Trombose/metabolismo , Humanos , Aprendizado de Máquina , Selectina-P/metabolismo , Estudo de Prova de Conceito
20.
Artigo em Inglês | MEDLINE | ID: mdl-32667389

RESUMO

Blastocystis sp. is a protist commonly found in stool samples of humans and animals. Biological and genetic factors of this organism remain controversial. The present study aimed to develop and implement the Blastocystis in vitro culture of Brazilian human isolates for routine use. The fecal isolates (n = 20) were maintained in our laboratory by several passages in Pavlova's medium. Cultures were monitored every 72 h by light microscopy. Genomic DNA was extracted to identify the subtypes (STs). In most isolates, the vacuolar form was prevalent. The amoeboid, granular and cystic forms were observed during in vitro cultivation. STs 1, 2, 3, 4 and 7 were identified. Our preliminary results show the generation time and forms present in the in vitro culture of Blastocystis subtypes isolated from Brazilian human isolates. Therefore, we emphasize the use of in vitro culture as a tool in future studies for the better understanding of the biological aspects of Blastocystis sp.


Assuntos
Infecções por Blastocystis/parasitologia , Blastocystis/genética , Técnicas de Cultura de Células/métodos , Fezes/parasitologia , Microscopia/métodos , Reação em Cadeia da Polimerase/métodos , Animais , Blastocystis/citologia , Blastocystis/isolamento & purificação , Infecções por Blastocystis/diagnóstico , Brasil , Humanos , Prevalência
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