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1.
Endocr Connect ; 10(7): 707-714, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34077391

RESUMO

BACKGROUND: Thyroid nodules diagnosed as 'atypia of undetermined significance/follicular lesion of undetermined significance' (AUS/FLUS) or 'follicular neoplasm/suspected follicular neoplasm' (FN/SFN), according to Bethesda's classification, represent a challenge in clinical practice. Computerized analysis of nuclear images (CANI) could be a useful tool for these cases. Our aim was to evaluate the ability of CANI to correctly classify AUS/FLUS and FN/SFN thyroid nodules for malignancy. METHODS: We studied 101 nodules cytologically classified as AUS/FLUS (n = 68) or FN/SFN (n = 33) from 97 thyroidectomy patients. Slides with cytological material were submitted for manual selection and analysis of the follicular cell nuclei for morphometric and texture parameters using ImageJ software. The histologically benign and malignant lesions were compared for such parameters which were then evaluated for the capacity to predict malignancy using the classification and regression trees gini model. The intraclass coefficient of correlation was used to evaluate method reproducibility. RESULTS: In AUS/FLUS nodule analysis, the benign and malignant nodules differed for entropy (P < 0.05), while the FN/SFN nodules differed for fractal analysis, coefficient of variation (CV) of roughness, and CV-entropy (P < 0.05). Considering the AUS/FLUS and FN/SFN nodules separately, it correctly classified 90.0 and 100.0% malignant nodules, with a correct global classification of 94.1 and 97%, respectively. We observed that reproducibility was substantially or nearly complete (0.61-0.93) in 10 of the 12 nuclear parameters evaluated. CONCLUSION: CANI demonstrated a high capacity for correctly classifying AUS/FLUS and FN/SFN thyroid nodules for malignancy. This could be a useful method to help increase diagnostic accuracy in the indeterminate thyroid cytology.

2.
Endocr Connect ; 7(8): 907-913, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29973373

RESUMO

BACKGROUND: Computerized image analysis seems to represent a promising diagnostic possibility for thyroid tumors. Our aim was to evaluate the discriminatory diagnostic efficiency of computerized image analysis of cell nuclei from histological materials of follicular tumors. METHODS: We studied paraffin-embedded materials from 42 follicular adenomas (FA), 47 follicular variants of papillary carcinomas (FVPC) and 20 follicular carcinomas (FC) by the software ImageJ. Based on the nuclear morphometry and chromatin texture, the samples were classified as FA, FC or FVPC using the Classification and Regression Trees method. RESULTS: We observed high diagnostic sensitivity and specificity rates (FVPC: 89.4% and 100%; FC: 95.0% and 92.1%; FA: 90.5 and 95.5%, respectively). When the tumors were compared by pairs (FC vs FA, FVPC vs FA), 100% of the cases were classified correctly. CONCLUSION: The computerized image analysis of nuclear features showed to be a useful diagnostic support tool for the histological differentiation between follicular adenomas, follicular variants of papillary carcinomas and follicular carcinomas.

3.
An Acad Bras Cienc ; 88(3): 1511-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27556225

RESUMO

The most common cause of spinal cord injury are high impact trauma, which often result in some motor impairment, sensory or autonomic a greater or lesser extent in the distal areas the level of trauma. In terms of survival and complications due to sequelae, veterinary patients have a poor prognosis unfavorable. Therefore justified the study of experimental models of spinal cord injury production that could provide more support to research potential treatments for spinal cord injuries in medicine and veterinary medicine. Preclinical studies of acute spinal cord injury require an experimental animal model easily reproducible. The most common experimental animal model is the rat, and several techniques for producing a spinal cord injury. The objective of this study was to describe and evaluate the effectiveness of acute spinal cord injury production technique through inflation of Fogarty(r) catheter using rabbits as an experimental model because it is a species that has fewer conclusive publications and contemplating. The main requirements of a model as low cost, handling convenience, reproducibility and uniformity. The technique was adequate for performing preclinical studies in neuro-traumatology area, effectively leading to degeneration and necrosis of the nervous tissue fostering the emergence of acute paraplegia.


Assuntos
Catéteres , Modelos Animais de Doenças , Compressão da Medula Espinal/etiologia , Animais , Espaço Epidural , Coelhos , Reprodutibilidade dos Testes
4.
Cell Biochem Biophys ; 68(2): 247-57, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23793960

RESUMO

Resveratrol (RSV) is known for its antioxidant properties; however, this compound has been proposed to have cytotoxic and pro-oxidant effects depending on its concentration and time of exposure. We previously reported the cell cycle arrest effect of low doses of RSV in GRX cells, an activated hepatic stellate cell model. Here, we evaluated the effects of RSV treatment (0.1-50 µM) for 24 and 120 h on GRX viability and oxidative status. Only treatment with 50 µM of RSV reduced the amount of live cells. However, even low doses of RSV induced an increased reactive species production at both treatment times. While being diminished within 24 h, RSV induced an increase in the SOD activity in 120 h. The cellular damage was substantially increased at 24 h in the 50 µM RSV-treated group, as indicated by the high lipoperoxidation, which may be related to the significant cell death and low proliferation. Paradoxically, this cellular damage and lipoperoxidation were considerably reduced in this group after 120 h of treatment while the surviving cells proliferated. In conclusion, RSV induced a dose-dependent pro-oxidant effect in GRX cells. The highest RSV dose induced oxidative-related damage, drastically reducing cell viability; but this cytotoxicity seems to be attenuated during 120 h of treatment.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Catalase/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Resveratrol , Estilbenos/química , Superóxido Dismutase/metabolismo , Fatores de Tempo
5.
Mol Cell Biochem ; 315(1-2): 1-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18454344

RESUMO

Resveratrol (RSV) exerts anti-proliferative and pro-apoptotic actions in different cell lines. Hepatic stellate cells (HSCs) are major fibrogenic cell types that contribute to collagen accumulation during chronic liver disease. In the present study, the inhibitory effects of RSV on cell proliferation, cell cycle, and apoptosis were evaluated in the mouse hepatic stellate cell line GRX. Cells treated with 1 nM-1 muM of RSV demonstrated a decrease in cell growth of about 35% after 5 days. GRX cells, treated with RSV (100 nM or 1 muM), were analyzed by flow cytometry; RSV induced an increase in the number of GRX cells in the S- and sub-G1 phases. The increase in sub-G1 phase cells and the nuclear condensation and fragmentation shown by DAPI staining identified a possible pro-apoptotic effect of RSV on GRX cells. Furthermore, the RSV anti-proliferative effects could be explained by an S-phase accumulation caused by a decrease in the progression through the cell cycle or an inhibition of S or G2 phase transition. It is notable that these RSV actions are mediated at nanomolar levels, compatible with the concentrations of free RSV in biological fluids after ingestion of polyphenol-rich foods, suggesting a possible effect of these foods as an adjuvant treatment in chronic liver diseases.


Assuntos
Ciclo Celular/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Resveratrol , Fase S/efeitos dos fármacos
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