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1.
Med Image Anal ; 72: 102115, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34134084

RESUMO

Scoliosis is a common medical condition, which occurs most often during the growth spurt just before puberty. Untreated Scoliosis may cause long-term sequelae. Therefore, accurate automated quantitative estimation of spinal curvature is an important task for the clinical evaluation and treatment planning of Scoliosis. A couple of attempts have been made for automated Cobb angle estimation on single-view x-rays. It is very challenging to achieve a highly accurate automated estimation of Cobb angles because it is difficult to utilize x-rays efficiently. With the idea of developing methods for accurate automated spinal curvature estimation, AASCE2019 challenge provides spinal anterior-posterior x-ray images with manual labels for training and testing the participating methods. We review eight top-ranked methods from 12 teams. Experimental results show that overall the best performing method achieved a symmetric mean absolute percentage (SMAPE) of 21.71%. Limitations and possible future directions are also described in the paper. We hope the dataset in AASCE2019 and this paper could provide insights into quantitative measurement of the spine.


Assuntos
Escoliose , Coluna Vertebral , Algoritmos , Humanos , Radiografia , Escoliose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Raios X
2.
Med Image Anal ; 73: 102166, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34340104

RESUMO

Vertebral labelling and segmentation are two fundamental tasks in an automated spine processing pipeline. Reliable and accurate processing of spine images is expected to benefit clinical decision support systems for diagnosis, surgery planning, and population-based analysis of spine and bone health. However, designing automated algorithms for spine processing is challenging predominantly due to considerable variations in anatomy and acquisition protocols and due to a severe shortage of publicly available data. Addressing these limitations, the Large Scale Vertebrae Segmentation Challenge (VerSe) was organised in conjunction with the International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI) in 2019 and 2020, with a call for algorithms tackling the labelling and segmentation of vertebrae. Two datasets containing a total of 374 multi-detector CT scans from 355 patients were prepared and 4505 vertebrae have individually been annotated at voxel level by a human-machine hybrid algorithm (https://osf.io/nqjyw/, https://osf.io/t98fz/). A total of 25 algorithms were benchmarked on these datasets. In this work, we present the results of this evaluation and further investigate the performance variation at the vertebra level, scan level, and different fields of view. We also evaluate the generalisability of the approaches to an implicit domain shift in data by evaluating the top-performing algorithms of one challenge iteration on data from the other iteration. The principal takeaway from VerSe: the performance of an algorithm in labelling and segmenting a spine scan hinges on its ability to correctly identify vertebrae in cases of rare anatomical variations. The VerSe content and code can be accessed at: https://github.com/anjany/verse.


Assuntos
Benchmarking , Tomografia Computadorizada por Raios X , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Coluna Vertebral/diagnóstico por imagem
3.
Opt Lett ; 34(18): 2861-3, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19756130

RESUMO

This research investigated the feasibility of employing beam-profile-adapted optical feedback to conduct commercial multi-transverse-mode vertical-cavity surface-emitting lasers (VCSELs) to emit a single transverse mode with a wide tuning range. Experimentally, for a VCSEL with its solitary spectrum consisting of almost no fundamental transverse mode, the fundamental transverse mode could be conducted to lase with a tuning range of about 1285 GHz and side-mode suppression ratio of around 20 dB. These results can greatly enhance the performance of VCSELs in many applications.

4.
Mar Drugs ; 6(4): 595-606, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19172197

RESUMO

Many biomedical products have already been obtained from marine organisms. In order to search more therapeutic drugs against cancer, this study demonstrates the cytotoxicity effects of Cladiella australis, Clavularia viridis and Klyxum simplex extracts on human oral squamous cell carcinoma (SCC4, SCC9 and SCC25) cells using cell adhesion and cell viability assay. The morphological alterations in SCCs cells after treatment with three extracts, such as typical nuclear condensation, nuclear fragmentation and apoptotic bodies of cells were demonstrated by Hoechst stain. Flow cytometry indicated that three extracts sensitized SCC25 cells in the G(0)/G(1) and S-G(2)/M phases with a concomitant significantly increased sub-G(1) fraction, indicating cell death by apoptosis. This apoptosis process was accompanied by activation of caspase-3 expression after SCC25 cells were treated with three extracts. Thereby, it is possible that extracts of C. australis, C. viridis and K. simplex cause apoptosis of SCCs and warrant further research investigating the possible anti-oral cancer compounds in these soft corals.


Assuntos
Antozoários/química , Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Bucais/tratamento farmacológico , Animais , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/metabolismo , Caspase 3/metabolismo , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citometria de Fluxo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Bucais/metabolismo , Extratos de Tecidos/farmacologia
5.
Gene ; 561(1): 115-23, 2015 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-25680291

RESUMO

Wild Chinese horseshoe bats have been proven to be natural reservoirs of SARS-like coronaviruses. However, the molecular characterization of key proteins in bats still needs to be explored further. In this study, we used cloning and bioinformatics to analyze the sequence of RIG-I, STAT-1 and IFN-ß in the immortalized cell lines from Rhinolophus affinis and Rhinolophus sinicus. Then, we treated different bat cells, mouse embryonic fibroblasts (MEF) and splenocytes with polyinosinic-polycytidylic acid (polyI:C) and vesicular stomatitis virus (VSV) to assess and compare antiviral immune responses between bats and mice. Our results demonstrated that bat RIG-I, STAT-1 and IFN-ß showed close homology with human, mouse, pig and rhesus monkey. RIG-I and STAT-1 were both highly expressed in bat spleen. Furthermore, IFN-ß was induced by polyI:C and VSV in both bat and mouse cells. These findings have provided new insight into the potential characteristics of the bat innate immune system against viral infection.


Assuntos
Quirópteros/imunologia , Interferon beta/genética , Fator de Transcrição STAT1/genética , Ubiquitina-Proteína Ligases/genética , Estomatite Vesicular/imunologia , Sequência de Aminoácidos , Animais , Antivirais/farmacologia , Sequência de Bases , Linhagem Celular , Quirópteros/genética , Humanos , Imunidade Inata/imunologia , Interferon beta/biossíntese , Camundongos , Dados de Sequência Molecular , Poli I-C/farmacologia , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência , Vírus da Estomatite Vesicular Indiana/imunologia
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