Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Artículo en Inglés | MEDLINE | ID: mdl-37813596

RESUMEN

BACKGROUND AND OBJECTIVES: Optical coherence tomography angiography (OCTA) is a noninvasive high-resolution imaging technique for assessing the retinal vasculature and is increasingly used in various ophthalmologic, neuro-ophthalmologic, and neurologic diseases. To date, there are no validated consensus criteria for quality control (QC) of OCTA. Our study aimed to develop criteria for OCTA quality assessment. METHODS: To establish criteria through (1) extensive literature review on OCTA artifacts and image quality to generate standardized and easy-to-apply OCTA QC criteria, (2) application of OCTA QC criteria to evaluate interrater agreement, (3) identification of reasons for interrater disagreement, revision of OCTA QC criteria, development of OCTA QC scoring guide and training set, and (4) validation of QC criteria in an international, interdisciplinary multicenter study. RESULTS: We identified 7 major aspects that affect OCTA quality: (O) obvious problems, (S) signal strength, (C) centration, (A) algorithm failure, (R) retinal pathology, (M) motion artifacts, and (P) projection artifacts. Seven independent raters applied the OSCAR-MP criteria to a set of 40 OCTA scans from people with MS, Sjogren syndrome, and uveitis and healthy individuals. The interrater kappa was substantial (κ 0.67). Projection artifacts were the main reason for interrater disagreement. Because artifacts can affect only parts of OCTA images, we agreed that prior definition of a specific region of interest (ROI) is crucial for subsequent OCTA quality assessment. To enhance artifact recognition and interrater agreement on reduced image quality, we designed a scoring guide and OCTA training set. Using these educational tools, 23 raters from 14 different centers reached an almost perfect agreement (κ 0.92) for the rejection of poor-quality OCTA images using the OSCAR-MP criteria. DISCUSSION: We propose a 3-step approach for standardized quality control: (1) To define a specific ROI, (2) to assess the occurrence of OCTA artifacts according to the OSCAR-MP criteria, and (3) to evaluate OCTA quality based on the occurrence of different artifacts within the ROI. OSCAR-MP OCTA QC criteria achieved high interrater agreement in an international multicenter study and is a promising QC protocol for application in the context of future clinical trials and studies.


Asunto(s)
Vasos Retinianos , Tomografía de Coherencia Óptica , Humanos , Consenso , Angiografía con Fluoresceína/métodos , Retina/diagnóstico por imagen
2.
Graefes Arch Clin Exp Ophthalmol ; 260(5): 1789-1797, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34962592

RESUMEN

PURPOSE: To detect SARS-CoV-2 RNA in post-mortem human eyes. Ocular symptoms are common in patients with COVID-19. In some cases, they can occur before the onset of respiratory and other symptoms. Accordingly, SARS-CoV-2 RNA has been detected in conjunctival samples and tear film of patients suffering from COVID-19. However, the detection and clinical relevance of intravitreal SARS-CoV-2 RNA still remain unclear due to so far contradictory reports in the literature. METHODS: In our study 20 patients with confirmed diagnosis of COVID-19 were evaluated post-mortem to assess the conjunctival and intraocular presence of SARS-CoV-2 RNA using sterile pulmonary and conjunctival swabs as well as intravitreal biopsies (IVB) via needle puncture. SARS-CoV-2 PCR and whole genome sequencing from the samples of the deceased patients were performed. Medical history and comorbidities of all subjects were recorded and analyzed for correlations with viral data. RESULTS: SARS-CoV-2 RNA was detected in 10 conjunctival (50%) and 6 vitreal (30%) samples. SARS-CoV-2 whole genome sequencing showed the distribution of cases largely reflecting the frequency of circulating lineages in the Munich area at the time of examination with no preponderance of specific variants. Especially there was no association between the presence of SARS-CoV-2 RNA in IVBs and infection with the variant of concern (VOC) alpha. Viral load in bronchial samples correlated positively with load in conjunctiva but not the vitreous. CONCLUSION: SARS-CoV-2 RNA can be detected post mortem in conjunctival tissues and IVBs. This is relevant to the planning of ophthalmologic surgical procedures in COVID-19 patients, such as pars plana vitrectomy or corneal transplantation. Furthermore, not only during surgery but also in an outpatient setting it is important to emphasize the need for personal protection in order to avoid infection and spreading of SARS-CoV-2. Prospective studies are needed, especially to determine the clinical relevance of conjunctival and intravitreal SARS-CoV-2 detection concerning intraocular affection in active COVID-19 state and in post-COVID syndrome.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Conjuntiva , Humanos , ARN Viral/genética , SARS-CoV-2/genética , Lágrimas/química
3.
Laryngoscope ; 132(7): 1334-1339, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34415055

RESUMEN

OBJECTIVES/HYPOTHESIS: Tumor-infiltrating lymphocytes (TILs) predict better outcome in several types of cancers. However, the prognostic value of TILs in sinonasal mucosal melanoma (SNMM) is uncertain. Here, we investigated whether TILs can be used as a prognostic indicator for survival in SNMM. STUDY DESIGN: Retrospective cohort study. METHODS: Patient history and histologic specimens from 27 patients with primary SNMM were retrospectively analyzed. TIL grade was determined and associations between TILs and AJCC tumor stage, overall survival, and recurrence-free survival were analyzed. RESULTS: Patients with TILs in the primary tumor classified as brisk or non-brisk survived significantly longer than patients with SNMMs lacking lymphocyte infiltrates. Brisk TILs were associated with the lower T3 stage and increased recurrence-free and 5-year survival. CONCLUSION: Our results indicate that TIL density is a strong prognostic factor for better survival in SNMM. Prospective studies with larger case numbers are warranted to determine whether TILs should be included in future AJCC staging guidelines. LEVEL OF EVIDENCE: 3 Laryngoscope, 132:1334-1339, 2022.


Asunto(s)
Melanoma , Neoplasias de los Senos Paranasales , Neoplasias Cutáneas , Humanos , Linfocitos Infiltrantes de Tumor/patología , Neoplasias de los Senos Paranasales/patología , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Neoplasias Cutáneas/patología
5.
Sci Signal ; 8(402): ra112, 2015 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-26554816

RESUMEN

Megakaryoblastic leukemia 1 (MKL1) is a coactivator of serum response factor (SRF) that promotes the expression of genes associated with cell proliferation, motility, adhesion, and differentiation-processes that also involve dynamic cytoskeletal changes in the cell. MKL1 is inactive when bound to monomeric globular actin (G-actin), but signals that activate the small guanosine triphosphatase RhoA cause actin polymerization and MKL1 dissociation from G-actin. We found a new mechanism of MKL1 activation that is mediated through its binding to filamin A (FLNA), a protein that binds filamentous actin (F-actin). The interaction of FLNA and MKL1 was required for the expression of MKL1 target genes in primary fibroblasts, melanoma, mammary and hepatocellular carcinoma cells. We identified the regions of interaction between MKL1 and FLNA, and cells expressing an MKL1 mutant that was unable to bind FLNA exhibited impaired cell migration and reduced expression of MKL1-SRF target genes. Induction and repression of MKL1-SRF target genes correlated with increased or decreased MKL1-FLNA interaction, respectively. Lysophosphatidic acid-induced RhoA activation in primary human fibroblasts promoted the association of endogenous MKL1 with FLNA, whereas exposure to an actin polymerization inhibitor dissociated MKL1 from FLNA and decreased MKL1-SRF target gene expression in melanoma cells. Thus, FLNA functions as a positive cellular transducer linking actin polymerization to MKL1-SRF activity, counteracting the known repressive complex of MKL1 and monomeric G-actin.


Asunto(s)
Movimiento Celular/fisiología , Filaminas/metabolismo , Factor de Respuesta Sérica/metabolismo , Transactivadores/metabolismo , Células 3T3 , Actinas/química , Actinas/metabolismo , Animales , Línea Celular , Línea Celular Tumoral , Células Cultivadas , Filaminas/química , Filaminas/genética , Regulación de la Expresión Génica , Células Hep G2 , Humanos , Ratones , Modelos Biológicos , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Invasividad Neoplásica , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Transactivadores/química , Transactivadores/genética , Técnicas del Sistema de Dos Híbridos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...