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1.
J Cell Sci ; 135(5)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33975358

RESUMO

Lipid droplets (LDs) are lipid-rich organelles universally found in most cells. They serve as a key energy reservoir, actively participate in signal transduction and dynamically communicate with other organelles. LD dysfunction has been associated with a variety of diseases. The content level, composition and mobility of LDs are crucial for their physiological and pathological functions, and these different parameters of LDs are subject to regulation by genetic factors and environmental inputs. Coherent Raman scattering (CRS) microscopy utilizes optical nonlinear processes to probe the intrinsic chemical bond vibration, offering label-free, quantitative imaging of lipids in vivo with high chemical specificity and spatiotemporal resolution. In this Review, we provide an overview over the principle of CRS microscopy and its application in tracking different parameters of LDs in live cells and organisms. We also discuss the use of CRS microscopy in genetic screens to discover lipid regulatory mechanisms and in understanding disease-related lipid pathology.


Assuntos
Microscopia , Análise Espectral Raman , Biologia , Gotículas Lipídicas , Lipídeos
2.
Sensors (Basel) ; 21(21)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34770677

RESUMO

The non-invasive examination of conjunctival goblet cells using a microscope is a novel procedure for the diagnosis of ocular surface diseases. However, it is difficult to generate an all-in-focus image due to the curvature of the eyes and the limited focal depth of the microscope. The microscope acquires multiple images with the axial translation of focus, and the image stack must be processed. Thus, we propose a multi-focus image fusion method to generate an all-in-focus image from multiple microscopic images. First, a bandpass filter is applied to the source images and the focus areas are extracted using Laplacian transformation and thresholding with a morphological operation. Next, a self-adjusting guided filter is applied for the natural connections between local focus images. A window-size-updating method is adopted in the guided filter to reduce the number of parameters. This paper presents a novel algorithm that can operate for a large quantity of images (10 or more) and obtain an all-in-focus image. To quantitatively evaluate the proposed method, two different types of evaluation metrics are used: "full-reference" and "no-reference". The experimental results demonstrate that this algorithm is robust to noise and capable of preserving local focus information through focal area extraction. Additionally, the proposed method outperforms state-of-the-art approaches in terms of both visual effects and image quality assessments.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Microscopia
3.
Lab Chip ; 21(22): 4357-4363, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34723299

RESUMO

We report the Muscope, a miniature lensless holographic microscope suitable for on-chip integration. The prototype of the Muscope measured approximately only 7 mm × 4 mm × 4 mm, and was capable of offering a sub-micron half-pitch resolution. We have used, for the first time, a microLED display as the light source in a microscope. The individual pixels of a microLED display chip are used as programmable, microscopic and intense LEDs which can be spatially moved in a two-dimensional plane with a 5 µm pitch. This unique feature set of the display was used to implement computational super-resolution and wide-field imaging without any extra hardware, unlike many other lensless microscopes. We also report a new method to evaluate the magnification in our setting. The Muscope surpasses the existing lensless microscopes in compactness, scalability for production, automated operation and system integration. It provides exciting opportunities for a new class of devices with in-built optical imaging and monitoring and/or sensing capabilities.


Assuntos
Holografia , Microscopia , Imagem Óptica
4.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 33(5): 496-500, 2021 Oct 27.
Artigo em Chinês | MEDLINE | ID: mdl-34791847

RESUMO

OBJECTIVE: To re-examine the diagnosis results of reported malaria cases in Sichuan Province from 2014 to 2020, so as to assess the malaria diagnostic capability of Sichuan Provincial Malaria Diagnostic Reference Laboratory. METHODS: The blood and blood smear samples from reported malaria cases were collected by Sichuan Provincial Malaria Diagnostic Reference Laboratory from 2014 to 2020, and subjected to re-examinations using microscopy and nested PCR assay. The re-examination results were compared. RESULTS: A total of 1 710 samples from reported malaria cases were re-examined by Sichuan Provincial Malaria Diagnostic Reference Laboratory from 2014 to 2020, and 1 634 samples were identified positive, with a positive coincidence rate of 95.56% (1 634/1 710) and a 92.29% (1 508/1 634) total coincidence rate of the Plasmodium species. The coincidence rates with P. falciparum, P. vivax, P. malariae and P. ovale were 99.48% (961/966), 97.07% (430/443), 83.05% (98/118) and 67.86% (19/28), respectively, and the coincidence rate was 91.81% (1 513/1 648) between microscopic and nested-PCR results. CONCLUSIONS: The capability of microscopists remains weak at grassroot medical institutions in Sichuan Province. Further training is required among microscopists to improve the malaria surveillance capability in Sichuan Province during the post-elimination stage.


Assuntos
Malária , Plasmodium , Testes Diagnósticos de Rotina , Humanos , Laboratórios , Malária/diagnóstico , Malária/epidemiologia , Microscopia , Plasmodium/genética
5.
Artif Intell Med ; 121: 102197, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34763799

RESUMO

Melanoma is an aggressive neoplasm responsible for the majority of deaths from skin cancer. Specifically, spitzoid melanocytic tumors are one of the most challenging melanocytic lesions due to their ambiguous morphological features. The gold standard for its diagnosis and prognosis is the analysis of skin biopsies. In this process, dermatopathologists visualize skin histology slides under a microscope, in a highly time-consuming and subjective task. In the last years, computer-aided diagnosis (CAD) systems have emerged as a promising tool that could support pathologists in daily clinical practice. Nevertheless, no automatic CAD systems have yet been proposed for the analysis of spitzoid lesions. Regarding common melanoma, no system allows both the selection of the tumor region and the prediction of the benign or malignant form in the diagnosis. Motivated by this, we propose a novel end-to-end weakly supervised deep learning model, based on inductive transfer learning with an improved convolutional neural network (CNN) to refine the embedding features of the latent space. The framework is composed of a source model in charge of finding the tumor patch-level patterns, and a target model focuses on the specific diagnosis of a biopsy. The latter retrains the backbone of the source model through a multiple instance learning workflow to obtain the biopsy-level scoring. To evaluate the performance of the proposed methods, we performed extensive experiments on a private skin database with spitzoid lesions. Test results achieved an accuracy of 0.9231 and 0.80 for the source and the target models, respectively. In addition, the heat map findings are directly in line with the clinicians' medical decision and even highlight, in some cases, patterns of interest that were overlooked by the pathologist.


Assuntos
Melanoma , Neoplasias Cutâneas , Biópsia , Diagnóstico por Computador , Humanos , Melanoma/diagnóstico , Microscopia , Neoplasias Cutâneas/diagnóstico
6.
J Biomed Opt ; 26(11)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34775694

RESUMO

SIGNIFICANCE: High-speed three-dimensional (3D) super-resolution microscopy is a unique tool to investigate various biological phenomena; yet the technology is not broadly adopted due to its high cost and complex system design. AIM: We present a compact, low-cost, and high-speed 3D structured illumination microscopy (SIM) based on a digital micromirror device and binary holography to visualize fast biological events with super-resolution. APPROACH: The 3D SIM uses a digital micromirror device to generate three laser foci with individually controllable positions, phases, and amplitudes via binary holography at the back aperture of objective lens to form optimal 3D structured patterns. Fifteen raw images are sequentially recorded and processed by the 3D SIM algorithm to reconstruct a super-resolved image. RESULTS: Super-resolution 3D imaging at a speed of 26.7 frames per second is achieved with a lateral and axial resolution of 155 and 487 nm, which corresponds to a 1.65- and 1.63-times resolution enhancement, respectively, comparing with standard deconvolution microscopy. CONCLUSIONS: The 3D SIM realizes fast super-resolution imaging with optimal 3D structured illumination, which may find important applications in biophotonics.


Assuntos
Holografia , Imageamento Tridimensional , Algoritmos , Iluminação , Microscopia
7.
Clin Lab ; 67(11)2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34758221

RESUMO

BACKGROUND: Automated microscopic platforms are increasingly used in clinical laboratories for rapid analysis of samples. However, it is important to present the results quantitatively or semiquantitatively because automated platforms use various technologies for analysis as well as different sediment preparation methods. The results of cell counting using an on screen image review program for the cobas u 701 analyzer (Roche Diagnostics Interna-tional, Rotkreuz, Switzerland) differed from those obtained by manual microscopic examination (MME). This study was performed to investigate the difference of results among analyzer, on-screen image review and MME. METHODS: Freshly collected urine specimens from outpatients were used. We calculated the mean, standard deviation, and 95% confidence interval for red and white blood cell (RBC/WBC) quantitative results obtained using the cobas u 701 analyzer. These results were compared to those obtained by manual counting. RBC and WBC counts determined with the cobas u 701 analyzer were compared to those obtained by MME per unit field. RESULTS: The semiquantitative results of MME were graded as 0 - 2, 3 - 5, 6 - 10, 11 - 20, 21 - 30, and many or numerous cells/high power field (HPF). The RBC and WBC counts determined by image analyses showed the tendency to be one grade higher than those from MME in the range of 3 to 5/HPF to many/HPF. The results of nearly all samples with 0 - 2/HPF and numerous/HPF for RBC and WBC counts were consistent with the grade found by MME. CONCLUSIONS: The one-grade difference may have been caused by the differences of preanalytical factors in the sample volume, centrifugal force, urine concentration ratio, or sediment volume/area of the slide. When reporting the results of image analyses, RBC and WBC counts should be raised by one grade to compensate for MME. Each laboratory needs to verify the on-screen review of images corresponding to the microscopic field of view according to the clinical laboratory's specific preanalytical practices.


Assuntos
Microscopia , Urinálise , Laboratórios , Contagem de Leucócitos , Leucócitos , Urina
8.
Korean J Parasitol ; 59(5): 537-542, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34724776

RESUMO

This study intended to record a species of feather mite, Neopteronyssus bilineatus Mironov, 2003, (Arachnida: Pteronyssidae), from a grey-capped pygmy woodpecker, Yungipicus canicapillus (Blyth, 1845), in the Republic of Korea. Mite samples were collected from the flight feathers of a woodpecker, preserved directly in 95% ethyl alcohol, and then observed by a light microscope after specimen preparation. Morphology of Neopteronyssus bilineatus is distinguished from other pici group species by opisthosoma part with 2 longitudinal bends, tarsal seta rIII 3 times longer than tarsus III in males, and 2 elongated hysteronotal plates extending beyond the level of setae e2 in females. In the present study, a species of feather mite, N. bilineatus, was newly recorded from Y. canicapillus in Korean fauna.


Assuntos
Aves/parasitologia , Infestações por Ácaros , Ácaros , Animais , Feminino , Masculino , Microscopia , Infestações por Ácaros/veterinária , República da Coreia
9.
Mikrobiyol Bul ; 55(4): 603-616, 2021 Oct.
Artigo em Turco | MEDLINE | ID: mdl-34666659

RESUMO

Microscopic methods are accepted as the gold standard in the diagnosis of malaria and in the followup of treatment. However, as the microscopical methods require experienced personnel, it is important to confirm the diagnosis with a different method for accurate diagnosis and treatment follow-up. In our study, we aimed to investigate the utility of the use of real time reverse transcriptase polymerase chain reaction (rRT-PCR), as well as microscopic methods for malaria treatment follow-up. In our study, we formed five groups each consisting of five male Balb/c mice. Each mouse was injected intraperitoneally with 107/ml Plasmodium berghei parasites. After 48 hours following the injection, the mice in the first, second and third groups received 50 mg/kg/day of chloroquine treatment for one, two and three days, respectively. The fourth group was not treated and the fifth group of mice received saline for three days. The parasitemia was monitored for 21 days by blood smears prepared from the end of tail of the mice and searching the presence of the target gene region of the parasite by rRT-PCR. Both the blood smears and rRT-PCR results were positive for groups I, II, IV and V. Both blood smears and rRT-PCR results of mice in groups other than the third group were found to be positive. Blood smears of the mice in third group were found to be positive on the 5th and 7th days of the infection, and the subsequent preparations were evaluated as negative. rRT-PCR results showed positivity on day seven, but no presence of the target gene region of the parasite was detected on the other days. The comparison of microscopy and rRT-PCR methods, had shown parallel results. Apart from the microscopic examination method, it was concluded that the rRT-PCR method is important in the diagnosis of malaria and in the follow-up of the patient during the treatment process, and that different methods that support each other should be used.


Assuntos
Malária , Animais , Cloroquina , Seguimentos , Humanos , Malária/diagnóstico , Malária/tratamento farmacológico , Masculino , Camundongos , Microscopia , Plasmodium berghei/genética , Reação em Cadeia da Polimerase em Tempo Real
10.
Medicine (Baltimore) ; 100(37): e27206, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34664854

RESUMO

RATIONALE: We report a new scleral buckling technique using a 27-gauge endoilluminator and a wide-field viewing system to overcome the limitations of conventional indirect ophthalmoscope-methods and "chandelier-assisted" surgery. PATIENT CONCERNS: A 26-year-old female patient visited the local clinic for floaters and lower visual field defects in her left eye that had occurred 5 days prior. DIAGNOSES: On fundus examination, upper retinal detachment without macular involvement and an atrophic hole was observed in her left eye. INTERVENTIONS: Under general anesthesia and after perilimbal conjunctival incision, extraocular muscle isolation, and traction with black silk, a 27-gauge trocar-cannula was inserted 90° away from the retinal break, 4 mm away from the limbus. Under wide-field viewing using a contact lens, the fundus was observed through a surgical microscope. Retinal break was evaluated and cryopexy was performed with careful movement of the endoilluminator, paying attention to damage to the lens. The surgeon could accurately and freely control the direction of the illumination tip to obtain a brighter view of the region of interest. OUTCOMES: There were no complications associated with trocar cannula incision or the illuminator. The retina was successfully reattached. LESSONS: Twenty seven gauge endoilluminator-assisted scleral buckling is an easy and safe procedure and provides better control over and free adjustment of the light direction, thus overcoming the limitations of chandelier-assisted surgery.


Assuntos
Recurvamento da Esclera/métodos , Adulto , Feminino , Humanos , Iluminação/instrumentação , Iluminação/normas , Microscopia/instrumentação , Microscopia/métodos , Recurvamento da Esclera/instrumentação , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/métodos
11.
Sensors (Basel) ; 21(19)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34640939

RESUMO

Lightfield microscopy has raised growing interest in the last few years. Its ability to get three-dimensional information about the sample in a single shot makes it suitable for many applications in which time resolution is fundamental. In this paper we present a novel device, which is capable of converting any conventional microscope into a lightfield microscope. Based on the Fourier integral microscope concept, we designed the lightfield microscope eyepiece. This is coupled to the eyepiece port, to let the user exploit all the host microscope's components (objective turret, illumination systems, translation stage, etc.) and get a 3D reconstruction of the sample. After the optical design, a proof-of-concept device was built with off-the-shelf optomechanical components. Here, its optical performances are demonstrated, which show good matching with the theoretical ones. Then, the pictures of different samples taken with the lightfield eyepiece are shown, along with the corresponding reconstructions. We demonstrated the functioning of the lightfield eyepiece and lay the foundation for the development of a commercial device that works with any microscope.


Assuntos
Iluminação , Microscopia
12.
Int J Mol Sci ; 22(19)2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34639083

RESUMO

We used infrared (IR) microscopy to monitor in real-time the metabolic turnover of individual mammalian cells in morphologically different states. By relying on the intrinsic absorption of mid-IR light by molecular components, we could discriminate the metabolism of adherent cells as compared to suspended cells. We identified major biochemical differences between the two cellular states, whereby only adherent cells appeared to rely heavily on glycolytic turnover and lactic fermentation. We also report spectroscopic variations that appear as spectral oscillations in the IR domain, observed only when using synchrotron infrared radiation. We propose that this effect could be used as a reporter of the cellular conditions. Our results are instrumental in establishing IR microscopy as a label-free method for real-time metabolic studies of individual cells in different morphological states, and in more complex cellular ensembles.


Assuntos
Adesão Celular , Metaboloma , Microscopia/métodos , Análise de Célula Única/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Síncrotrons/instrumentação , Glicólise , Células HEK293 , Humanos , Raios Infravermelhos
13.
Anal Chem ; 93(42): 14146-14152, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34648265

RESUMO

Second-harmonic generation (SHG) microscopy has been proved to be a powerful method for investigating the structures of biomaterials. SHG spectra were also generally used to probe the adsorption and cross-membrane transport of molecules on lipid bilayers in situ and in real time. In this work, we applied SHG and two-photon fluorescence (TPF) spectra to investigate the dynamics of an amphiphilic ion with an SHG and TPF chromophore, D289 (4-(4-diethylaminostyry)-1-methyl-pyridinium iodide), on the surface of human chronic myelogenous leukemia (K562) cells and the subcellular structures inside the cells. The adsorption and cross-membrane transport of D289 into the cells and then into the organelles such as mitochondria were revealed. SHG images were also recorded and used to demonstrate their capability of probing molecular dynamics in organelles in K562 cells. This work demonstrated the first SHG investigation of the cross-membrane transport dynamics on the surface of subcellular organelles. It may also shed light on the differentiation of different types of subcellular structures in cells.


Assuntos
Microscopia de Geração do Segundo Harmônico , Humanos , Microscopia , Simulação de Dinâmica Molecular , Organelas , Análise Espectral
14.
Rev Chilena Infectol ; 38(4): 558-561, 2021 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-34652403

RESUMO

One of the works, probably less known, of Antoine van Leeuwenhoek (1632-1723) is his Arcana naturae detecta (Detected secrets of nature) published in its first edition in 1695. This work is a compilation of 38 letters on scientific issues and it is beautifully illustrated. A notable section of the work is the observation and description for the first time of fermentation yeasts and his experiments on the spontaneous generation of microorganisms.


Assuntos
Microscopia
15.
Nature ; 598(7879): 65-71, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34616057

RESUMO

The human eye can distinguish as many as 10,000 different colours but is far less sensitive to variations in intensity1, meaning that colour is highly desirable when interpreting images. However, most biological samples are essentially transparent, and nearly invisible when viewed using a standard optical microscope2. It is therefore highly desirable to be able to produce coloured images without needing to add any stains or dyes, which can alter the sample properties. Here we demonstrate that colorimetric histology images can be generated using full-sized plasmonically active microscope slides. These slides translate subtle changes in the dielectric constant into striking colour contrast when samples are placed upon them. We demonstrate the biomedical potential of this technique, which we term histoplasmonics, by distinguishing neoplastic cells from normal breast epithelium during the earliest stages of tumorigenesis in the mouse MMTV-PyMT mammary tumour model. We then apply this method to human diagnostic tissue and validate its utility in distinguishing normal epithelium, usual ductal hyperplasia, and early-stage breast cancer (ductal carcinoma in situ). The colorimetric output of the image pixels is compared to conventional histopathology. The results we report here support the hypothesis that histoplasmonics can be used as a novel alternative or adjunct to general staining. The widespread availability of this technique and its incorporation into standard laboratory workflows may prove transformative for applications extending well beyond tissue diagnostics. This work also highlights opportunities for improvements to digital pathology that have yet to be explored.


Assuntos
Colorimetria/instrumentação , Colorimetria/métodos , Técnicas Histológicas/instrumentação , Microscopia/instrumentação , Animais , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Estudos de Coortes , Modelos Animais de Doenças , Feminino , Humanos , Antígeno Ki-67/análise , Camundongos , Camundongos Endogâmicos C57BL
16.
Nat Commun ; 12(1): 5934, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34635658

RESUMO

Estimating the orientation and 3D position of rotationally constrained emitters with localization microscopy typically requires polarization splitting or a large engineered Point Spread Function (PSF). Here we utilize a compact modified PSF for single molecule emitter imaging to estimate simultaneously the 3D position, dipole orientation, and degree of rotational constraint from a single 2D image. We use an affordable and commonly available phase plate, normally used for STED microscopy in the excitation light path, to alter the PSF in the emission light path. This resulting Vortex PSF does not require polarization splitting and has a compact PSF size, making it easy to implement and combine with localization microscopy techniques. In addition to a vectorial PSF fitting routine we calibrate for field-dependent aberrations which enables orientation and position estimation within 30% of the Cramér-Rao bound limit over a 66 µm field of view. We demonstrate this technique on reorienting single molecules adhered to the cover slip, λ-DNA with DNA intercalators using binding-activated localization microscopy, and we reveal periodicity on intertwined structures on supercoiled DNA.


Assuntos
DNA Super-Helicoidal/ultraestrutura , DNA/ultraestrutura , Imageamento Tridimensional/métodos , Microscopia/métodos , Sítios de Ligação , DNA/metabolismo , DNA Super-Helicoidal/metabolismo , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/metabolismo , Imageamento Tridimensional/instrumentação , Substâncias Intercalantes/química , Substâncias Intercalantes/metabolismo , Microscopia/instrumentação
17.
Transl Vis Sci Technol ; 10(12): 30, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34668935

RESUMO

Purpose: Two-photon excitation fluorescence (2PEF) reveals information about tissue function. Concerns for phototoxicity demand lower light exposure during imaging. Reducing excitation light reduces the quality of the image by limiting fluorescence emission. We applied deep learning (DL) super-resolution techniques to images acquired from low light exposure to yield high-resolution images of retinal and skin tissues. Methods: We analyzed two methods: a method based on U-Net and a patch-based regression method using paired images of skin (550) and retina (1200), each with low- and high-resolution paired images. The retina dataset was acquired at low and high laser powers from retinal organoids, and the skin dataset was obtained from averaging 7 to 15 frames or 70 frames. Mean squared error (MSE) and the structural similarity index measure (SSIM) were outcome measures for DL algorithm performance. Results: For the skin dataset, the patches method achieved a lower MSE (3.768) compared with U-Net (4.032) and a high SSIM (0.824) compared with U-Net (0.783). For the retinal dataset, the patches method achieved an average MSE of 27,611 compared with 146,855 for the U-Net method and an average SSIM of 0.636 compared with 0.607 for the U-Net method. The patches method was slower (303 seconds) than the U-Net method (<1 second). Conclusions: DL can reduce excitation light exposure in 2PEF imaging while preserving image quality metrics. Translational Relevance: DL methods will aid in translating 2PEF imaging from benchtop systems to in vivo imaging of light-sensitive tissues such as the retina.


Assuntos
Aprendizado Profundo , Processamento de Imagem Assistida por Computador , Humanos , Imageamento por Ressonância Magnética , Microscopia , Fotofobia
18.
BMC Bioinformatics ; 22(1): 531, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34715773

RESUMO

BACKGROUND: Time-lapse microscopy live-cell imaging is essential for studying the evolution of bacterial communities at single-cell resolution. It allows capturing detailed information about the morphology, gene expression, and spatial characteristics of individual cells at every time instance of the imaging experiment. The image analysis of bacterial "single-cell movies" (videos) generates big data in the form of multidimensional time series of measured bacterial attributes. If properly analyzed, these datasets can help us decipher the bacterial communities' growth dynamics and identify the sources and potential functional role of intra- and inter-subpopulation heterogeneity. Recent research has highlighted the importance of investigating the role of biological "noise" in gene regulation, cell growth, cell division, etc. Single-cell analytics of complex single-cell movie datasets, capturing the interaction of multiple micro-colonies with thousands of cells, can shed light on essential phenomena for human health, such as the competition of pathogens and benign microbiome cells, the emergence of dormant cells ("persisters"), the formation of biofilms under different stress conditions, etc. However, highly accurate and automated bacterial bioimage analysis and single-cell analytics methods remain elusive, even though they are required before we can routinely exploit the plethora of data that single-cell movies generate. RESULTS: We present visualization and single-cell analytics using R (ViSCAR), a set of methods and corresponding functions, to visually explore and correlate single-cell attributes generated from the image processing of complex bacterial single-cell movies. They can be used to model and visualize the spatiotemporal evolution of attributes at different levels of the microbial community organization (i.e., cell population, colony, generation, etc.), to discover possible epigenetic information transfer across cell generations, infer mathematical and statistical models describing various stochastic phenomena (e.g., cell growth, cell division), and even identify and auto-correct errors introduced unavoidably during the bioimage analysis of a dense movie with thousands of overcrowded cells in the microscope's field of view. CONCLUSIONS: ViSCAR empowers researchers to capture and characterize the stochasticity, uncover the mechanisms leading to cellular phenotypes of interest, and decipher a large heterogeneous microbial communities' dynamic behavior. ViSCAR source code is available from GitLab at https://gitlab.com/ManolakosLab/viscar .


Assuntos
Processamento de Imagem Assistida por Computador , Filmes Cinematográficos , Bactérias/genética , Humanos , Microscopia , Software
19.
J Contemp Dent Pract ; 22(7): 735-738, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34615776

RESUMO

AIM AND OBJECTIVE: This study aimed to compare microleakage of resin-modified glass ionomer cement (RMGIC) and alkasite with and without adhesive system in class V cavity. MATERIALS AND METHODS: Thirty class V cavities were prepared on the buccal surface. All prepared samples were randomly divided into three groups. Group I was restored with RMGIC, group II was restored with Cention N after the application of adhesive system, and group III was restored with alkasite. Samples were subjected to 200 thermocycles between temperature baths at 5ºC and 55ºC. Samples were stained with 2% methylene blue. The teeth were sectioned longitudinally, and the sections were then observed under stereomicroscope at a magnification of 20×. RESULTS: Statistical analysis showed that there was less microleakage in Cention N using adhesive system in both occlusal margin and gingival margin. CONCLUSION: There were significant differences between RMGIC, alkasite with adhesive system, and alkasite without adhesive system in class V cavity. Least microleakage at the occlusal margin and gingival margin was seen with Cention N using adhesive system and highest microleakage at the RMGIC. CLINICAL SIGNIFICANCE: Cention N using the adhesive system affects the microleakage in the class V restoration. The study theorizes that the material restorations showed less microleakage in the occlusal margin than in the gingival margin.


Assuntos
Cimentos Dentários , Cimentos de Ionômeros de Vidro , Microscopia , Projetos de Pesquisa
20.
J Contemp Dent Pract ; 22(7): 812-828, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34615789

RESUMO

AIM: The assessment of hyalinization to determine aggressive behavior in oral pathological lesions is a scarcely researched field that requires further exploration. The current study aims to predict the biological behavior of oral hyalinizing extraosseous lesions (OHEOL) by employing four differential stains with clinicopathologic correlation. MATERIALS AND METHODS: The study was performed on retrospectively diagnosed formalin-fixed paraffin-embedded cases of salivary gland tumors (SGTs) (n = 13), benign soft tissue (BST) lesions (n = 24), and oral submucous fibrosis (OSMF) (n = 53). The hematoxylin and eosin-stained sections were analyzed for the severity of hyalinization (SOH). Differential stains periodic acid Schiff (PAS), Alcian blue, safranin O, and picrosirius red with polarizing microscopy were used to assess the components of hyalinized tissue. The SOH was correlated with differential staining characteristics and clinicopathologic features to analyze possible correlation with aggressive potential in BST, advancement of disease in OSMF, and recurrence in SGT. RESULTS: Intensity of picrosirius red stain significantly correlated with SOH of SGTs (p = 0.044). The intensity of PAS stain (p = 0.040), picrosirius red polarizing greenish-yellow color (p = 0.002), and pattern of distribution of picrosirius red (p = 0.023) significantly correlated with recurrence of SGTs. The intensity of differential stains increased with the SOH in BST lesions indicating their correlation with SOH. The intensity (p = 0.008) and pattern (p = 0.010) of Alcian blue staining and intensity of safranin O stain (p = 0.003) significantly correlated with SOH in OSMF. Picrosirius red polarizing color reddish and yellowish red (p = 0.002) significantly correlated with SOH distinguishing early and advanced OSMF. CONCLUSION: Picrosirius red and PAS stains are reliable indicators of SOH and recurrence potential in SGT. Alcian blue, safranin O, and picrosirius red polarizing colors enable detection of SOH and accurately distinguish early from advanced OSMF. CLINICAL SIGNIFICANCE: SOH can be considered as a histological predictor of aggressive biologic behavior in OHEOL. These findings will result in appropriate management protocols.


Assuntos
Corantes , Microscopia , Estudos Retrospectivos , Coloração e Rotulagem
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