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1.
Artigo em Inglês | MEDLINE | ID: mdl-22255014

RESUMO

All patient-related medical information during a hospital stay in France, has to be collected and coded in the compilation of medical units discharge documents, according to a standardized approach. The process of describing a patient disease in terms of appropriate diagnostic codes is nevertheless, a non-intuitive operation for the physician. As a consequence, coding errors, inaccuracies and missing data are frequent, leading to potentially severe economical upshots. A coding support system developed to improve medical coding results, integrates three information processing methodologies, using the outputs from various Hospital Information System applications. Each methodology generates partial heterogeneous information, with considerable semantic variety. In order to properly synthesize these outputs, information fusion is required to produce enriched contextualized information, presented to the physician as an ordered list of suggested codes. This paper explores two information fusion approaches: voting system and possibilistic. Both methods are tested on a database of 1,000 discharge summaries, to show the interest of information fusion in this context. Results show that fusion methods perform better in most of the cases than partial information extraction methods.


Assuntos
Codificação Clínica , Diagnóstico , França , Humanos , Tempo de Internação , Probabilidade
2.
Artigo em Inglês | MEDLINE | ID: mdl-21096565

RESUMO

For the practitioner, choosing diagnosis codes is a non-intuitive operation. Mistakes are frequent, causing severe consequences on healthcare performance evaluation and funding. French physicians have to assign a code to all their activities and are frequently prone to these errors. Given that most of the time and particularly for chronic diseases indexed information is already available, we propose a tool named AnterOcod, in order to support the medical coding task. It suggests the list of most relevant plausible codes, predicted from the patient's earlier hospital stays, according to a set of previously utilized diagnosis codes. Our method applies the estimation of code reappearance rates, based on an equivalent approach to actuarial survival curves. Around 33% of the expected correct diagnosis codes were retrieved in this manner, after evaluating 998 discharge abstracts, significantly improving the coding task.


Assuntos
Análise Atuarial/métodos , Doença Crônica/classificação , Doença Crônica/mortalidade , Codificação Clínica/métodos , Codificação Clínica/estatística & dados numéricos , Análise de Sobrevida , França/epidemiologia , Humanos , Prevalência , Taxa de Sobrevida
3.
Artigo em Inglês | MEDLINE | ID: mdl-19963581

RESUMO

Choosing diagnosis codes is a non-intuitive operation for the practitioner. Mistakes are frequent with severe consequences on healthcare evaluation and funding. French physicians have to assign a code for everything they do and they are not spared with these kinds of errors. We propose a tool named REFEROCOD to support the medical coding task in order to minimize errors without losing time, by suggesting a list of codes in accordance with the physician activities and of the patient medical context. The proposed method uses probabilistic knowledge and indicates the probability to have a proper diagnosis code considering the realized procedure, age, sex and other information available in the discharge abstract.


Assuntos
Controle de Formulários e Registros , Informática Médica/instrumentação , Algoritmos , Gráficos por Computador , Técnicas de Apoio para a Decisão , Feminino , Humanos , Masculino , Erros Médicos/prevenção & controle , Informática Médica/métodos , Prontuários Médicos , Probabilidade , Software , Interface Usuário-Computador
4.
Artigo em Inglês | MEDLINE | ID: mdl-18003012

RESUMO

Clinical assessment of venous thrombosis (VT) is essential to evaluate the risk of size increase or embolism. Analyses like echogenecity and echostructure characterization, examine ancillary evidence to improve diagnosis. However, such analyses are inherently uncertain and operator dependent, adding enormous complexity to the task of indexing diagnosed images for medical practice support, by retrieving similar images, or to exploit electronic patient record repositories for data mining. This paper proposes a VT ultrasound image indexing and retrieval approach, which shows the suitability of neural network VT characterization, combined with a fuzzy similarity. Three types of image descriptors (sliding window, wavelet coefficients energy and co-occurrence matrix), are processed by three different neural networks, producing equivalent VT characterizations. Resulting values are projected on fuzzy membership functions and then compared with the fuzzy similarity. Compared to nominal and Euclidean distances, an experimental validation indicates that the fuzzy similarity increases image retrieval precision beyond the identification of images that belong to the same diagnostic class, taking into account the characterization result uncertainty, and allowing the user to privilege any particular feature.


Assuntos
Angiografia/métodos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Ultrassonografia/métodos , Trombose Venosa/diagnóstico por imagem , Humanos , Sensibilidade e Especificidade
5.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 3349-52, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17946562

RESUMO

Finding pertinent images in large picture archiving systems, for advanced medical practice support is becoming increasingly difficult. One possible solution to such emerging problem is image indexing. This work proposes to evaluate the indexing and retrieval performance of various 3D anatomical indexing approaches, in order to assist surgery planning based on similar cases. The evaluation examines the indexing performance of 5 feature descriptors (simple statistic, cord- based, shape distribution, surface curvature, and 3D Hough transform) and the retrieval performance of 5 similarity measures (the Minkowski norms L1 L2 and L(infinity), the Bhattacharyya distance, and the chi2-divergence). A database of 21 patients, with an average of 11 3D anatomical surfaces per patient was used. The combined performance of feature descriptors and similarity measurements was evaluated with the Bull-Eye Percentage score. Experimental results indicate that there are several possible optimal indexing and retrieval approaches, depending on the surface characteristics.


Assuntos
Imageamento Tridimensional/estatística & dados numéricos , Modelos Anatômicos , Cirurgia Assistida por Computador/estatística & dados numéricos , Engenharia Biomédica , Bases de Dados Factuais , Humanos
6.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 3775-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281051

RESUMO

Distant diagnostic services require the exchange of medical images and medical data in the form of specialized patient records. Given that multiple images for one patient are often used by these services, considerable demands are placed on support applications implementation, because of the processing and transmission infrastructure limitations found on isolated rural areas. This work proposes to evaluate the performance of medical image compression for such constrained scenario, based on the JPEG 2000 compression standard, in order to improve distant diagnostic services usability. Separate groups of 1 to 15 high resolution gray scale and color cytology images of fixed dimensions were compressed in one file, applying different possible bitrates, tile size and code-block size, for six discrete wavelet decomposition levels. Experimental results show that the adjustment of these parameters, allows compressing the worst data load case (135 MB with moderate lossy compression) in around two minutes, on an average current PC.

7.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 4002-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281109

RESUMO

Venous thrombosis screening exams use 2D ultrasound images, from which medical experts obtain a rough idea of the thrombosis aspect and infer an approximate volume. Such estimation is essential to follow up the thrombosis evolution. This paper proposes a method to calculate venous thrombosis volume from non-parallel 2D ultrasound images, taking advantage of a priori knowledge about the thrombosis shape. An interactive ellipse fitting contour segmentation extracts the 2D thrombosis contours. Then, a Delaunay triangulation is applied to the set of 2D segmented contours positioned in 3D, and the area that each contour defines, to obtain a global thrombosis 3D surface reconstruction, with a dense triangulation inside the contours. Volume is calculated from the obtained surface and contours triangulation, using a maximum unit normal component approach. Preliminary results obtained on 3 plastic phantoms and 3 in vitro venous thromboses, as well as one in vivo case are presented and discussed. An error rate of volume estimation inferior to 4,5% for the plastic phantoms, and 3,5% for the in vitro venous thromboses was obtained.

8.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 2224-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17282674

RESUMO

Medical image security can be enhanced using watermarking, which allows embedding the protection information as a digital signature, by modifying the pixel gray levels of the image. In this paper we propose a reversible watermarking scheme which guarantees that once the embedded message is read, alterations introduced during the insertion process can be removed from the image. Thereafter, original pixel gray levels of the image are restored. The proposed approach relies on estimation of image signal that is invariant to the insertion process, and permits to introduce a very slight watermark within the image. In fact, the insertion process adds or subtracts at least one gray level to the pixels of the original image. Depending on the image to be watermarked, in our case angiographic images of the retina, it is expected that such image alteration will not have any impact on the diagnosis quality, and consequently that the watermark can be kept within the image while this one is interpreted.

12.
J Antibiot (Tokyo) ; 53(5): 474-8, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10908110

RESUMO

A novel bioactive macrolide, IB-96212 has been isolated from the fermentation broth of a marine actinomycete, L-25-ES25-008. The strain belongs to the genus Micromonospora. The macrolide showed a very strong cytotoxic activity against P-388, and lower but significant activity against A-549, HT-29, and MEL-28 cell lines. We describe the isolation, taxonomy and fermentation of the producing strain as well as the isolation of IB-96212.


Assuntos
Antibacterianos/farmacologia , Macrolídeos , Micromonospora/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular , Ensaios de Seleção de Medicamentos Antitumorais , Fermentação , Humanos , Testes de Sensibilidade Microbiana , Micromonospora/ultraestrutura , Microscopia Eletrônica de Varredura , Estrutura Molecular
13.
J Antibiot (Tokyo) ; 53(5): 479-83, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10908111

RESUMO

IB-96212, is a new member of spiroketal containing macrolide class of fermentation-derived natural products isolated from mycelial extracts of Micromonospora sp. The structure consists of a new aglycone which possesses a 26-membered macrolide ring system and of one deoxy sugar identified as L-rhodinose, this structure represents the first reported spiroketal macrolide natural product related to other macrolides, such as oligomycins, dunaimycins, citovaricin, rutamycin and ossamycin.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Macrolídeos , Micromonospora/metabolismo , Estrutura Molecular , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Análise Espectral
14.
Artif Intell Med ; 19(2): 155-83, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10814908

RESUMO

Cardiac motion analysis enables to identify pathologies related to myocardial anomalies or coronary arteries circulation deficiencies. Conventionally, bi-dimensional (2D) left ventricle contour images have been extensively used, to perform quantitative measurements and qualitative evaluations of the cardiac function. Nevertheless, there are other cardiac anatomical structures, the coronary arteries, imaged on routine procedures, upon which complementary motion interpretation can be conducted. This paper presents an experimental methodology to perform dynamic cardiac scenes interpretation, studying three-dimensional (3D) coronary arteries spatial-temporal behavior. Being an alternative way to approach computer assisted cardiac motion interpretation, it reveals a wide range of rarely explored spatial-temporal situations and proposes how to address them. Considering the challenges to achieve dynamic scene interpretation, it is explained how spatial and temporal knowledge, are connected to specialist knowledge and measured parameters, to obtain a dynamic scene interpretation. Global and local motion features are modeled according to cardiac motion and geometrical knowledge, before its transformation into symbols. Anatomical knowledge and spatial-temporal knowledge are applied, along with spatial-temporal reasoning schemes, to access symbols meaning. Experimental results obtained using real data are presented. Complexity of interpretation envisioning is discussed, taking the given results as an example.


Assuntos
Inteligência Artificial , Coração/fisiologia , Vasos Coronários/anatomia & histologia , Vasos Coronários/fisiologia , Ventrículos do Coração/anatomia & histologia , Humanos , Função Ventricular
15.
J Antibiot (Tokyo) ; 52(11): 983-7, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10656570

RESUMO

Agrochelin, a new alkaloid cytotoxic substance, was produced by the fermentation of Agrobacterium sp. The compound was obtained from the bacterial cells by solvent extraction and purified by silica gel chromatography. Agrochelin (1) and its acetyl derivative (2) exhibited cytotoxic activity.


Assuntos
Antibióticos Antineoplásicos/isolamento & purificação , Rhizobium/classificação , Tiazóis/isolamento & purificação , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Fermentação , Humanos , Camundongos , Rhizobium/metabolismo , Tiazóis/química , Tiazóis/farmacologia , Células Tumorais Cultivadas
16.
Artif Intell Med ; 13(3): 207-37, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9698154

RESUMO

The aim of this paper is to describe a knowledge-based system that interprets three-dimensional (3D) coronary artery movement, using data from digital subtraction angiography image sequences. Dynamic information obtained from artery centerline 3D reconstruction and optical flow estimation, is classified according to experimental evidence indicating that artery displacements are quasi-homogeneous by a segment analysis. Characteristic motion features like displacement direction, perpendicular/radial components, rotation direction, curvature and torsion are qualitatively described from an image sequence using symbolic labels. These facts are then related and interpreted using anatomical-functional knowledge provided by a specialist, as well as spatial and temporal knowledge, applying spatio-temporal reasoning schemes. Facts, knowledge and reasoning rules are stated in a declarative form. Detailed examples of local and global interpretation results, using a real reconstructed angiographic biplane image sequence are presented in order to illustrate how our system suitably interprets coronary artery dynamic behavior.


Assuntos
Angiografia Digital , Inteligência Artificial , Vasos Coronários/fisiologia , Humanos
17.
J Antibiot (Tokyo) ; 51(1): 64-7, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9580130

RESUMO

Sesbanimides are cytotoxic compounds, originally isolated in 1983 from seeds of the leguminous plants Sesbania drummondii and Sesbania punicea. In this paper we describe the bacterial production of sesbanimides by two "marine Agrobacterium"; strain PH-103 which produces Sesbanimide-A and strain PH-A034C which produces Sesbanimide-C. The isolation and taxonomy of the producing microorganisms, fermentation and isolation of sesbanimides are reported.


Assuntos
Alcaloides , Antineoplásicos Fitogênicos/isolamento & purificação , Dissacarídeos/isolamento & purificação , Piperidinas/isolamento & purificação , Rhizobium/química , Antineoplásicos Fitogênicos/química , Dissacarídeos/química , Fermentação , Biologia Marinha , Piperidinas/química , Rhizobium/classificação , Rhizobium/metabolismo , Microbiologia da Água
18.
IEEE Trans Med Imaging ; 17(6): 857-71, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10048843

RESUMO

This paper aims to define and describe features of the motion of coronary arteries in two and three dimensions, presented as geometrical parameters that identify motion patterns. The main left coronary artery centerlines, obtained from digital subtraction angiography (DSA) image sequences, are first reconstructed. Thereafter, global and local motion features are evaluated along the sequence. The global attributes are centerline and point trajectory lengths, displacement amplitude, and virtual reference point, while local attributes are displacement direction, perpendicular/radial components, rotation direction, and curvature and torsion. These kinetic features allow us to obtain a detailed quantitative description of the displacements of arteries' centerlines, as well as associated epicardium deformations. Our modeling of local attributes as quasi-homogeneous on a segment analysis, enables us to propose a novel numeric to symbolic image transformation, which provides the required facts for knowledge-based motion interpretation. Experimental results using real data are consistent with cardiac dynamic behavior.


Assuntos
Angiografia Digital/métodos , Angiografia Coronária/métodos , Algoritmos , Angiografia Digital/estatística & dados numéricos , Angiografia Coronária/estatística & dados numéricos , Vasos Coronários/fisiologia , Humanos , Movimento , Rotação , Anormalidade Torcional
19.
J Antibiot (Tokyo) ; 50(9): 734-7, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9360617

RESUMO

A novel bioactive depsipeptide, thiocoraline, was isolated from the mycelial cake of a marine actinomycete strain L-13-ACM2-092. Based on morphological, cultural, physiological, and chemical characteristics, strain L-13-ACM2-092 was ascribed to the genus Micromonospora. Thiocoraline showed a potent cytotoxic activity against P-388, A-549 and MEL-28 cell lines, and also a strong antimicrobial activity against Gram-positive microorganisms. This compound binds to supercoiled DNA and inhibits RNA synthesis.


Assuntos
Antibacterianos/isolamento & purificação , Antibióticos Antineoplásicos/isolamento & purificação , Depsipeptídeos , Peptídeos , Animais , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/farmacologia , Fermentação , Leucemia P388/tratamento farmacológico , Testes de Sensibilidade Microbiana , Micromonospora , Células Tumorais Cultivadas/efeitos dos fármacos
20.
J Antibiot (Tokyo) ; 50(9): 738-41, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9360618

RESUMO

Thiocoraline (1) is a new antitumor antibiotic isolated from the mycelium of Micromonospora sp. L-13-ACM2-092. Its structure was elucidated to be a novel cyclic thiodepsipeptide on the basis of spectroscopic methods.


Assuntos
Antibacterianos/química , Antibióticos Antineoplásicos/química , Depsipeptídeos , Peptídeos , Estrutura Molecular
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