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1.
Rev. esp. patol ; 57(2): 151-155, Abr-Jun, 2024. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-232423

RESUMO

Adenocarcinoma with enteroblastic differentiation is a rare histologic subtype of adenocarcinoma of the gastrointestinal tract that shows unique histologic and immunohistochemical features that resemble fetal intestinal epithelium. This histological subtype has been widely described in the stomach, where it most frequently appears, but, in other locations, it is misdiagnosed because of the poor experience in routine diagnostic setting. Here we present a case of an 87-year-old male with an adenocarcinoma of the ampulla of Vater with enteroblastic differentiation with a literature review of the cases described of this subtype in this location to date. The anatomical peculiarity of the ampulla, joined with the infrequent nature of this histological subtype, makes this case of great interest to aid to better characterize the biological behavior of these tumors. (AU)


El adenocarcinoma con diferenciación enteroblástica es un subtipo histológico poco frecuente de adenocarcinoma gastrointestinal que muestra características histológicas e inmunohistoquímicas únicas que se asemejan al epitelio intestinal fetal. Este subtipo histológico ha sido ampliamente descrito en el estómago, donde aparece con mayor frecuencia, pero en otras localizaciones es mal diagnosticado debido a la poca experiencia en el diagnóstico de rutina. Presentamos un caso de un varón de 87 años con adenocarcinoma de ampolla de Vater con diferenciación enteroblástica, junto a una revisión bibliográfica de los casos descritos de este subtipo en esta localización hasta el momento. La peculiaridad anatómica de la ampolla, sumada al carácter poco frecuente de este subtipo histológico, dotan a este caso de gran interés para ayudar a caracterizar mejor el comportamiento biológico de estos tumores. (AU)


Assuntos
Humanos , Adenocarcinoma , Ampola Hepatopancreática , Coloração e Rotulagem , Trato Gastrointestinal , Estômago
2.
J Cancer Res Clin Oncol ; 150(4): 172, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38565653

RESUMO

PURPOSE: Visualizing mitochondria in cancer cells from human pathological specimens may improve our understanding of cancer biology. However, using immunohistochemistry to evaluate mitochondria remains difficult because almost all cells contain mitochondria and the number of mitochondria per cell may have important effects on mitochondrial function. Herein, we established an objective system (Mito-score) for evaluating mitochondria using machine-based processing of hue, saturation, and value color spaces. METHODS: The Mito-score was defined as the number of COX4 (mitochondrial inner membrane) immunohistochemistry-positive pixels divided by the number of nuclei per cell. The system was validated using four lung cancer cell lines, normal tissues, and lung cancer tissues (199 cases). RESULTS: The Mito-score correlated with MitoTracker, a fluorescent dye used to selectively label and visualize mitochondria within cells under a microscope (R2 = 0.68) and with the number of mitochondria counted using electron microscopy (R2 = 0.79). Histologically, the Mito-score of small cell carcinoma (57.25) was significantly lower than that of adenocarcinoma (147.5, p < 0.0001), squamous cell carcinoma (120.6, p = 0.0004), and large cell neuroendocrine carcinoma (111.8, p = 0.002). CONCLUSION: The Mito-score method enables the analysis of the mitochondrial status of human formalin-fixed paraffin-embedded specimens and may provide insights into the metabolic status of cancer.


Assuntos
Formaldeído , Neoplasias Pulmonares , Humanos , Parafina , Inclusão em Parafina , Mitocôndrias , Coloração e Rotulagem
3.
Sci Data ; 11(1): 330, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570515

RESUMO

Variations in color and texture of histopathology images are caused by differences in staining conditions and imaging devices between hospitals. These biases decrease the robustness of machine learning models exposed to out-of-domain data. To address this issue, we introduce a comprehensive histopathology image dataset named PathoLogy Images of Scanners and Mobile phones (PLISM). The dataset consisted of 46 human tissue types stained using 13 hematoxylin and eosin conditions and captured using 13 imaging devices. Precisely aligned image patches from different domains allowed for an accurate evaluation of color and texture properties in each domain. Variation in PLISM was assessed and found to be significantly diverse across various domains, particularly between whole-slide images and smartphones. Furthermore, we assessed the improvement in domain shift using a convolutional neural network pre-trained on PLISM. PLISM is a valuable resource that facilitates the precise evaluation of domain shifts in digital pathology and makes significant contributions towards the development of robust machine learning models that can effectively address challenges of domain shift in histological image analysis.


Assuntos
Técnicas Histológicas , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Redes Neurais de Computação , Coloração e Rotulagem , Humanos , Amarelo de Eosina-(YS) , Processamento de Imagem Assistida por Computador/métodos , Histologia
4.
Med Image Anal ; 94: 103149, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574542

RESUMO

The variation in histologic staining between different medical centers is one of the most profound challenges in the field of computer-aided diagnosis. The appearance disparity of pathological whole slide images causes algorithms to become less reliable, which in turn impedes the wide-spread applicability of downstream tasks like cancer diagnosis. Furthermore, different stainings lead to biases in the training which in case of domain shifts negatively affect the test performance. Therefore, in this paper we propose MultiStain-CycleGAN, a multi-domain approach to stain normalization based on CycleGAN. Our modifications to CycleGAN allow us to normalize images of different origins without retraining or using different models. We perform an extensive evaluation of our method using various metrics and compare it to commonly used methods that are multi-domain capable. First, we evaluate how well our method fools a domain classifier that tries to assign a medical center to an image. Then, we test our normalization on the tumor classification performance of a downstream classifier. Furthermore, we evaluate the image quality of the normalized images using the Structural similarity index and the ability to reduce the domain shift using the Fréchet inception distance. We show that our method proves to be multi-domain capable, provides a very high image quality among the compared methods, and can most reliably fool the domain classifier while keeping the tumor classifier performance high. By reducing the domain influence, biases in the data can be removed on the one hand and the origin of the whole slide image can be disguised on the other, thus enhancing patient data privacy.


Assuntos
Corantes , Neoplasias , Humanos , Corantes/química , Coloração e Rotulagem , Algoritmos , Diagnóstico por Computador , Processamento de Imagem Assistida por Computador/métodos
5.
J Biochem ; 175(4): 377-381, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38616641

RESUMO

Understanding the mechanisms of drug action in the brain, from the genetic to the neural circuit level, is crucial for the development of new agents that act upon the central nervous system. Determining the brain regions and neurons affected by a drug is essential for revealing its mechanism of action in the brain. c-Fos, a marker of neuronal activation, has been widely used to detect neurons activated by stimuli with high spatial resolution. In this review, the use of c-Fos for the visualization and manipulation of activated neurons is introduced. I also explain that a higher temporal resolution can be achieved by changing the staining method for visualization of c-Fos. Moreover, a new method that allows labeling and manipulating commonly activated neurons using two different stimuli is proposed.


Assuntos
Encéfalo , Neurônios , Coloração e Rotulagem
6.
Mymensingh Med J ; 33(2): 526-532, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38557536

RESUMO

Meconium-stained amniotic fluid is the passage of meconium by a fetus in utero during the antenatal period or in labour. It has for long been considered to be a bad predictor of fetal distress and meconium aspiration syndrome (MAS). The objective of this study was to find out the fetal outcome of MSAF and clear amniotic fluid. This cross- sectional comparative study was carried out in Upazilla Health Complex, Palash, Narshingdi from July 2016 to June 2017. A total of 100 pregnant women among them 50 women with MSAF and 50 women with clear liquor were studied to see the record of ANC, mode of delivery and fetal outcome by APGAR score. Study showed that among MSAF group 76.0% (n=38) had irregular ANC and 24.0% (n=12) had regular ANC whereas in clear liquor 86.0% (n=43) had regular ANC 14.0% had irregular ANC. Among MSAF (50 cases) thick meconium was in 20 cases (40.0%) and thin meconium was in 30 cases (60.0%). Regarding mode of delivery 52.0% (n=26) MSAF cases had instrumental delivery and Caesarean section compared to 24.0% (n=12) in clear liquor group. Regarding thick MSAF among 40.0% (n=20), (n=14) had low APGAR score and (n=6) had normal score at one minute and (n=9) low APGAR score and (n=11) normal score at five minutes. In clear liquor, among 100.0% (n=50), 20.0% (n=10) had low APGAR score and 80.0% (n=40) had normal score at one-minute and at five minutes 8.0% (n=4) had low APGAR score and 92.0% (n=46) had normal score. Among MSAF 26.0% (n=13) were admitted to SCBU compare to 12.0% (n=6) in clear liquor group. The mean SCBU stay was 3.1 days in MSAF whereas 1.2 days in clear liquor. Among MSAF babies 4.0% (n=2) had MAS compared to no MAS in clear liquor group. Regarding Survivalist 92.0% (n=46) were alive in MSAF whereas 100.0% all (n=50) were alive in clear liquor group.


Assuntos
Síndrome de Aspiração de Mecônio , Mecônio , Feminino , Recém-Nascido , Humanos , Gravidez , Líquido Amniótico , Cesárea , Coloração e Rotulagem
7.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557883

RESUMO

Quantitative phase imaging (QPI) provides 3D structural and morphological information for label free living cells. Unfortunately, this quantitative phase information cannot meet doctors' diagnostic requirements of the clinical "gold standard," which displays stained cells' pathological states based on 2D color features. To make QPI results satisfy the clinical "gold standard," the virtual staining method by QPI for label free lymphocytes based on self-supervised iteration Cycle-Consistent Adversarial Networks (CycleGANs) is proposed herein. The 3D phase information of QPI is, therefore, trained and transferred to a kind of 2D "virtual staining" image that is well in agreement with "gold standard" results. To solve the problem that unstained QPI and stained "gold standard" results cannot be obtained for the same label free living cell, the self-supervised iteration for the CycleGAN deep learning algorithm is designed to obtain a trained stained result as the ground truth for error evaluation. The structural similarity index of our virtual staining experimental results for 8756 lymphocytes is 0.86. Lymphocytes' area errors after converting to 2D virtual stained results from 3D phase information are less than 3.59%. The mean error of the nuclear to cytoplasmic ratio is 2.69%, and the color deviation from the "gold standard" is less than 6.67%.


Assuntos
Algoritmos , 60704 , Coloração e Rotulagem
8.
Methods Mol Biol ; 2787: 265-279, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38656496

RESUMO

Polyacrylamide gel electrophoresis (PAGE) is a widely used technique for separating proteins from complex plant samples. Prior to the analysis, proteins must be extracted from plant tissues, which are rather complex than other types of biological material. Different protocols have been applied depending on the protein source, such as seeds, pollen, leaves, roots, and flowers. Total protein amounts must also be determined before conducting gel electrophoresis. The most common methodologies include PAGE under native or denaturing conditions. Both procedures are used consequently for protein identification and characterization via mass spectrometry. Additionally, various staining procedures are available to visualize protein bands in the gel, facilitating the software-based digital evaluation of the gel through image acquisition.


Assuntos
Eletroforese em Gel de Poliacrilamida , Proteínas de Plantas , Plantas , Eletroforese em Gel de Poliacrilamida/métodos , Proteínas de Plantas/análise , Proteínas de Plantas/isolamento & purificação , Plantas/química , Proteômica/métodos , Software , Coloração e Rotulagem/métodos , Espectrometria de Massas/métodos
9.
Sci Rep ; 14(1): 9066, 2024 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643213

RESUMO

This in vitro study aimed to evaluate the feasibility of quantitative light-induced fluorescence (QLF) technology for detecting the presence and severity of microleakage of pit and fissure sealants. The areas of interest (AOIs) were 160 pits and fissures of 40 extracted permanent teeth. Fluorescent images were acquired using a QLF device, and the maximum fluorescence loss ΔFmax of each AOI was analyzed. After staining and cross-sectioning of the teeth, histological dye penetration was scored on a scale of 0 to 3. The relationship between ΔFmax and microleakage depth was analyzed, and the areas under the curve (AUCs) were calculated. The │ΔFmax│ increased as microleakage depth increased. The ΔFmax values of microleakage areas showed a strong significant correlation with the histological scores of dye penetration (r = - 0.72, P = 0.001). AUC analysis showed a high diagnostic accuracy for microleakage depth (AUC = 0.83-0.91). The highest AUC of 0.91 was found when differentiating the outer half microleakage of the sealant (histological score 0 vs. 1-3). QLF technology is effective in assessing the presence and severity of microleakage, suggesting its potential for noninvasive detection and monitoring of sealant microleakage in clinical settings.


Assuntos
Selantes de Fossas e Fissuras , Fluorescência Quantitativa Induzida por Luz , Projetos de Pesquisa , Corantes , Coloração e Rotulagem
10.
Clin Lab ; 70(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38623674

RESUMO

BACKGROUND: The purpose of this study was to determine the staining conditions and appropriate fan1 start time (FAN1ST) for Sysmex SP-50 to produce blood smears (BS) that reflect the true lymphocyte morphology of patient samples. METHODS: Using different start times of fan1, we obtained a set of 84 blood smear slides from 21 blood samples and measured 10,920 lymphocyte areas, which were then converted to compare lymphocyte sizes. We also performed a leukocyte differential count using Sysmex DI-60 on 202 blood smear slides prepared before and after the change in staining conditions and compared the results. RESULTS: The mean lymphocyte sizes at FAN1ST 0 second, 5 seconds, 10 seconds, and 30 seconds were 12.55 µm, 12.14 µm, 11.27 µm, and 10.50 µm, respectively. The mean differences in the preclassification of neutrophils, lymphocytes, monocytes, eosinophils, and basophils in DI-60, according to the SP-50 staining conditions, were 0.88, -1.58, -0.24, 0.37, and 0.07, respectively. CONCLUSIONS: Wright-Giemsa staining of blood smears prepared on the SP-50 showed that changing the pH of the concentrated phosphate buffer to 6.6 and adjusting the staining time did not affect the results of the leukocyte differential count. However, since fan1 was used to dry the blood smear on the SP-50 and the lymphocyte size gradually decreased as the start time was delayed, it was necessary to set a start time for fan1 that did not affect the lymphocyte size.


Assuntos
Monócitos , Neutrófilos , Humanos , Contagem de Leucócitos , Eosinófilos , Coloração e Rotulagem
11.
Eur J Histochem ; 68(2)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38624064

RESUMO

Antibody-based fluorescence analysis of female reproductive tissues in research of sexually transmitted diseases allows for an in-depth understanding of protein localization, interactions, and pathogenesis. However, in many cases, cryosectioning is not compatible with biosafety regulations; at all times, exposure of lab personnel and the public to potentially harmful pathogens from biological infectious material must be avoided; thus, formaldehyde fixation is essential. Due to formaldehyde's cross-linking properties, protein detection with antibodies can be impeded. To allow effective epitope binding during immunofluorescence of formalin-fixed paraffin-embedded vaginal tissue, we investigated two antigen retrieval methods. We tested these methods regarding their suitability for automated image analysis, facilitating reproducible quantitative microscopic data acquisition in sexually transmitted disease research. Heat-based retrieval at 80°C in citrate buffer proved to increase antibody binding to eosinophil protein and HSV-2 visibly and tissue morphology best, and was the most efficient for sample processing and quantitative analysis.


Assuntos
Formaldeído , Herpesvirus Humano 2 , Feminino , Humanos , Epitopos , Fixação de Tecidos/métodos , Eosinófilos/química , Imuno-Histoquímica , Antígenos/análise , Coloração e Rotulagem , Caminhada , Inclusão em Parafina
12.
J Biomed Opt ; 29(3): 036004, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38532927

RESUMO

Significance: There is a significant need for the generation of virtual histological information from coronary optical coherence tomography (OCT) images to better guide the treatment of coronary artery disease (CAD). However, existing methods either require a large pixel-wise paired training dataset or have limited capability to map pathological regions. Aim: The aim of this work is to generate virtual histological information from coronary OCT images, without a pixel-wise paired training dataset while capable of providing pathological patterns. Approach: We design a structurally constrained, pathology-aware, transformer generative adversarial network, namely structurally constrained pathology-aware convolutional transformer generative adversarial network (SCPAT-GAN), to generate virtual stained H&E histology from OCT images. We quantitatively evaluate the quality of virtual stained histology images by measuring the Fréchet inception distance (FID) and perceptual hash value (PHV). Moreover, we invite experienced pathologists to evaluate the virtual stained images. Furthermore, we visually inspect the virtual stained image generated by SCPAT-GAN. Also, we perform an ablation study to validate the design of the proposed SCPAT-GAN. Finally, we demonstrate 3D virtual stained histology images. Results: Compared to previous research, the proposed SCPAT-GAN achieves better FID and PHV scores. The visual inspection suggests that the virtual histology images generated by SCPAT-GAN resemble both normal and pathological features without artifacts. As confirmed by the pathologists, the virtual stained images have good quality compared to real histology images. The ablation study confirms the effectiveness of the combination of proposed pathological awareness and structural constraining modules. Conclusions: The proposed SCPAT-GAN is the first to demonstrate the feasibility of generating both normal and pathological patterns without pixel-wisely supervised training. We expect the SCPAT-GAN to assist in the clinical evaluation of treating the CAD by providing 2D and 3D histopathological visualizations.


Assuntos
Doença da Artéria Coronariana , Tomografia de Coerência Óptica , Humanos , Coração , Artefatos , Coloração e Rotulagem , Processamento de Imagem Assistida por Computador
13.
Sci Data ; 11(1): 295, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486039

RESUMO

In computational pathology, automatic nuclei instance segmentation plays an essential role in whole slide image analysis. While many computerized approaches have been proposed for this task, supervised deep learning (DL) methods have shown superior segmentation performances compared to classical machine learning and image processing techniques. However, these models need fully annotated datasets for training which is challenging to acquire, especially in the medical domain. In this work, we release one of the biggest fully manually annotated datasets of nuclei in Hematoxylin and Eosin (H&E)-stained histological images, called NuInsSeg. This dataset contains 665 image patches with more than 30,000 manually segmented nuclei from 31 human and mouse organs. Moreover, for the first time, we provide additional ambiguous area masks for the entire dataset. These vague areas represent the parts of the images where precise and deterministic manual annotations are impossible, even for human experts. The dataset and detailed step-by-step instructions to generate related segmentation masks are publicly available on the respective repositories.


Assuntos
Núcleo Celular , Aprendizado de Máquina , Animais , Humanos , Camundongos , Núcleo Celular/patologia , Processamento de Imagem Assistida por Computador/métodos , Coloração e Rotulagem
14.
Sci Adv ; 10(13): eadn3426, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38536925

RESUMO

Intraoperative histology is essential for surgical guidance and decision-making. However, frozen-sectioned hematoxylin and eosin (H&E) staining suffers from degraded accuracy, whereas the gold-standard formalin-fixed and paraffin-embedded (FFPE) H&E is too lengthy for intraoperative use. Stimulated Raman scattering (SRS) microscopy has shown rapid histology of brain tissue with lipid/protein contrast but is challenging to yield images identical to nucleic acid-/protein-based FFPE stains interpretable to pathologists. Here, we report the development of a semi-supervised stimulated Raman CycleGAN model to convert fresh-tissue SRS images to H&E stains using unpaired training data. Within 3 minutes, stimulated Raman virtual histology (SRVH) results that matched perfectly with true H&E could be generated. A blind validation indicated that board-certified neuropathologists are able to differentiate histologic subtypes of human glioma on SRVH but hardly on conventional SRS images. SRVH may provide intraoperative diagnosis superior to frozen H&E in both speed and accuracy, extendable to other types of solid tumors.


Assuntos
Encéfalo , Corantes , Humanos , Inclusão em Parafina/métodos , Coloração e Rotulagem , Amarelo de Eosina-(YS) , Formaldeído
15.
Analyst ; 149(8): 2232-2235, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38445898

RESUMO

Multidrug efflux pumps excrete a range of small molecules from bacterial cells. In this study, we show that bacterial efflux pumps have affinity for a range of SYTO™ dyes that are commonly used to label bacteria. Efflux pump activity will there lead to false negative results from bacterial staining and SYTO™ dyes should be used with caution on live samples.


Assuntos
Corantes , Proteínas de Membrana Transportadoras , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Membrana Transportadoras/farmacologia , Bactérias/metabolismo , Transporte Biológico , Coloração e Rotulagem , Proteínas de Bactérias/metabolismo , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla
16.
Med Image Anal ; 94: 103143, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38507894

RESUMO

Nuclei detection and segmentation in hematoxylin and eosin-stained (H&E) tissue images are important clinical tasks and crucial for a wide range of applications. However, it is a challenging task due to nuclei variances in staining and size, overlapping boundaries, and nuclei clustering. While convolutional neural networks have been extensively used for this task, we explore the potential of Transformer-based networks in combination with large scale pre-training in this domain. Therefore, we introduce a new method for automated instance segmentation of cell nuclei in digitized tissue samples using a deep learning architecture based on Vision Transformer called CellViT. CellViT is trained and evaluated on the PanNuke dataset, which is one of the most challenging nuclei instance segmentation datasets, consisting of nearly 200,000 annotated nuclei into 5 clinically important classes in 19 tissue types. We demonstrate the superiority of large-scale in-domain and out-of-domain pre-trained Vision Transformers by leveraging the recently published Segment Anything Model and a ViT-encoder pre-trained on 104 million histological image patches - achieving state-of-the-art nuclei detection and instance segmentation performance on the PanNuke dataset with a mean panoptic quality of 0.50 and an F1-detection score of 0.83. The code is publicly available at https://github.com/TIO-IKIM/CellViT.


Assuntos
Núcleo Celular , Redes Neurais de Computação , Humanos , Amarelo de Eosina-(YS) , Hematoxilina , Coloração e Rotulagem , Processamento de Imagem Assistida por Computador
17.
Clin Exp Dent Res ; 10(2): e869, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38433287

RESUMO

OBJECTIVE: This study aimed to compare the color change of computer-aided design (CAD)/computer-aided manufacturing (CAM) polymethyl methacrylate (PMMA) denture teeth and conventional acrylic teeth after immersion in three staining beverages (coffee, red tea, and cola) for a day, 7 days, and 30 days. MATERIALS AND METHODS: Group 1: Conventional acrylic teeth (n = 32). Group 2: Milled CAD/CAM teeth out of PMMA disc (n = 32). The specimens of each material were further divided into four subgroups: (1) Control group, distilled water (n = 16). (2) Red tea solution (n = 16). (3) Coffee solution (n = 16). (4) Cola (n = 16). The color change ( ∆ E $\unicode{x02206}E$ ) was assessed using a spectrophotometer at four time points: at the baseline (t0 ), on the 1st day (t1 ), on the 7th day (t2 ), and the 30th day (t3 ) of immersion. Kolmogorov-Smirnov test was applied, followed by performing independent samples t test, one-way analysis of variance and post-hoc Tukey tests to compare the color change values at different time points. RESULTS: The mean score of NBS values of the coffee solution indicates perceivable color change at the end of the 30th day in the conventional acrylic teeth group. It was 0.843 ± 0.395 at t1 , then increased to 1.017 ± 0.477 at t2 and to 2.259 ± 1.059 at t3 . There is a statistically significant difference (p < 0.05) in color change values between both tooth types at the end of the 30th day of immersion in red tea solution and a statistically significant difference at the end of the 7th day (p < 0.05) and the 30th day (p < 0.05) of immersion in coffee solution. CONCLUSIONS: CAD/CAM PMMA teeth are more color stable than conventional acrylic teeth after 30 days of immersion in coffee and red tea solution.


Assuntos
Café , Polimetil Metacrilato , Bebidas , Desenho Assistido por Computador , Coloração e Rotulagem , Dentaduras , Chá
18.
Int Ophthalmol ; 44(1): 139, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488945

RESUMO

PURPOSE: Endothelial cell loss (ECL) during Descemet membrane endothelial keratoplasty (DMEK) graft preparation has been shown to affect graft survival and the need for re-grafting. The purpose of this study was to quantitatively assess the impact of the plastic and glass mediums in contact with DMEK donor tissue during intra-operative graft staining on ECL. METHODS: Retrospective study that included patients who underwent DMEK surgery between January 2019 and June 2021 at Hôpital Maisonneuve-Rosemont and the Jewish General Hospital in Montreal, Canada. DMEK grafts were stained with 0.06% Trypan blue ophthalmic solution (VisionBlue®, Dutch Ophthalmic, USA, Exeter, NH) for 120 s in either a plastic or glass medium prior to delivery into the recipient's eye. The ECL was compared between the two groups 12-30 months post-operatively. RESULTS: ECL at 12-30 months was significantly less in the eyes that had received grafts stained in a plastic medium compared to those stained in a glass medium. Graft survival and re-bubbling was higher in the glass group however this difference was not statistically significant. CONCLUSION: Staining of the DMEK graft in a plastic medium caused less ECL compared to the glass medium.


Assuntos
Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Endotélio Corneano , Humanos , Perda de Células Endoteliais da Córnea/diagnóstico , Estudos Retrospectivos , Lâmina Limitante Posterior/cirurgia , Células Endoteliais , Azul Tripano , Coloração e Rotulagem , Sobrevivência de Enxerto , Doadores de Tecidos , Contagem de Células
19.
Methods Enzymol ; 695: 29-43, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38521589

RESUMO

G-quadruplexes (G4) are functionally important nucleic acid structures, involved in many cellular pathways. They are often dynamically regulated in cells, which makes detecting them in vivo challenging and dependent on sophisticated technical equipment. Therefore, in vitro studies are commonly performed as a first step to confirm a candidate sequence folds into a G4. Several methods have been developed, each with its individual pros and cons. A highly accessible and quick approach, without the need for specialized equipment, is the detection of G4s in native gels using light-up probes. These molecules become fluorescent after specifically binding to G4s. Several different classes have been discovered, emitting light in various colors, and some possess specificity for certain G4 topologies, which makes them highly versatile tools for G4 visualization. Here, we will explore the general procedure using the light-up probe NMM on RNA G4s and discuss advantages and limitations of this method.


Assuntos
Quadruplex G , RNA/química , Corantes Fluorescentes/química , DNA/metabolismo , Coloração e Rotulagem
20.
J Histochem Cytochem ; 72(4): 233-243, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38553997

RESUMO

Xylene is the commonest clearing agent even though it is hazardous and costly. This study evaluated the clearing properties of coconut oil as an alternative cost-effective clearing agent for histological processes. Ten (10) prostate samples fixed in formalin were taken and each one was cut into 4 before randomly separating them into four groups (A, B, C and D). Tissues were subjected to ascending grades of alcohol for dehydration. Group A was cleared in xylene and Groups B, C, and D were cleared at varying times of 1hr 30mins, 3hrs, and 4hrs in coconut oil respectively before embedding, sectioning, and staining were carried out. Gross and histological features were compared. Results indicated a significant shrinkage in coconut oil-treated specimen compared with the xylene-treated specimen and only the tissues cleared in coconut oil for 4hrs were as rigid as the tissues cleared in xylene (p > 0.05). No significant difference was found in either of the sections when checked for cellular details and staining quality (p > 0.999). Coconut oil is an efficient substitute for xylene in prostate tissues with a minimum clearing time of 4hrs, as it is environmentally friendly and less expensive, but causes significant shrinkage to prostate tissue.


Assuntos
Formaldeído , Xilenos , Óleo de Coco , Xilenos/química , Coloração e Rotulagem , Indicadores e Reagentes
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