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1.
J Med Internet Res ; 25: e41048, 2023 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-37200084

RESUMO

BACKGROUND: European national disparities in the integration of data linkage (ie, being able to match patient data between databases) into routine public health activities were recently highlighted. In France, the claims database covers almost the whole population from birth to death, offering a great research potential for data linkage. As the use of a common unique identifier to directly link personal data is often limited, linkage with a set of indirect key identifiers has been developed, which is associated with the linkage quality challenge to minimize errors in linked data. OBJECTIVE: The aim of this systematic review is to analyze the type and quality of research publications on indirect data linkage on health product use and care trajectories in France. METHODS: A comprehensive search for all papers published in PubMed/Medline and Embase databases up to December 31, 2022, involving linked French database focusing on health products use or care trajectories was realized. Only studies based on the use of indirect identifiers were included (ie, without a unique personal identifier available to easily link the databases). A descriptive analysis of data linkage with quality indicators and adherence to the Bohensky framework for evaluating data linkage studies was also realized. RESULTS: In total, 16 papers were selected. Data linkage was performed at the national level in 7 (43.8%) cases or at the local level in 9 (56.2%) studies. The number of patients included in the different databases and resulting from data linkage varied greatly, respectively, from 713 to 75,000 patients and from 210 to 31,000 linked patients. The diseases studied were mainly chronic diseases and infections. The objectives of the data linkage were multiple: to estimate the risk of adverse drug reactions (ADRs; n=6, 37.5%), to reconstruct the patient's care trajectory (n=5, 31.3%), to describe therapeutic uses (n=2, 12.5%), to evaluate the benefits of treatments (n=2, 12.5%), and to evaluate treatment adherence (n=1, 6.3%). Registries are the most frequently linked databases with French claims data. No studies have looked at linking with a hospital data warehouse, a clinical trial database, or patient self-reported databases. The linkage approach was deterministic in 7 (43.8%) studies, probabilistic in 4 (25.0%) studies, and not specified in 5 (31.3%) studies. The linkage rate was mainly from 80% to 90% (reported in 11/15, 73.3%, studies). Adherence to the Bohensky framework for evaluating data linkage studies showed that the description of the source databases for the linkage was always performed but that the completion rate and accuracy of the variables to be linked were not systematically described. CONCLUSIONS: This review highlights the growing interest in health data linkage in France. Nevertheless, regulatory, technical, and human constraints remain major obstacles to their deployment. The volume, variety, and validity of the data represent a real challenge, and advanced expertise and skills in statistical analysis and artificial intelligence are required to treat these big data.


Assuntos
Inteligência Artificial , Armazenamento e Recuperação da Informação , Humanos , Sistema de Registros , Hospitais , Big Data
2.
Bioinformatics ; 37(15): 2165-2174, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-33523112

RESUMO

MOTIVATION: The principle of Breiman's random forest (RF) is to build and assemble complementary classification trees in a way that maximizes their variability. We propose a new type of random forest that disobeys Breiman's principles and involves building trees with no classification errors in very large quantities. We used a new type of decision tree that uses a neuron at each node as well as an in-innovative half Christmas tree structure. With these new RFs, we developed a score, based on a family of ten new statistical information criteria, called Nguyen information criteria (NICs), to evaluate the predictive qualities of features in three dimensions. RESULTS: The first NIC allowed the Akaike information criterion to be minimized more quickly than data obtained with the Gini index when the features were introduced in a logistic regression model. The selected features based on the NICScore showed a slight advantage compared to the support vector machines-recursive feature elimination (SVM-RFE) method. We demonstrate that the inclusion of artificial neurons in tree nodes allows a large number of classifiers in the same node to be taken into account simultaneously and results in perfect trees without classification errors. AVAILABILITY AND IMPLEMENTATION: The methods used to build the perfect trees in this article were implemented in the 'ROP' R package, archived at https://cran.r-project.org/web/packages/ROP/index.html. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

3.
Bioinformatics ; 35(20): 4011-4019, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30865271

RESUMO

MOTIVATION: The development of high-throughput single-cell sequencing technologies now allows the investigation of the population diversity of cellular transcriptomes. The expression dynamics (gene-to-gene variability) can be quantified more accurately, thanks to the measurement of lowly expressed genes. In addition, the cell-to-cell variability is high, with a low proportion of cells expressing the same genes at the same time/level. Those emerging patterns appear to be very challenging from the statistical point of view, especially to represent a summarized view of single-cell expression data. Principal component analysis (PCA) is a most powerful tool for high dimensional data representation, by searching for latent directions catching the most variability in the data. Unfortunately, classical PCA is based on Euclidean distance and projections that poorly work in presence of over-dispersed count data with dropout events like single-cell expression data. RESULTS: We propose a probabilistic Count Matrix Factorization (pCMF) approach for single-cell expression data analysis that relies on a sparse Gamma-Poisson factor model. This hierarchical model is inferred using a variational EM algorithm. It is able to jointly build a low dimensional representation of cells and genes. We show how this probabilistic framework induces a geometry that is suitable for single-cell data visualization, and produces a compression of the data that is very powerful for clustering purposes. Our method is competed against other standard representation methods like t-SNE, and we illustrate its performance for the representation of single-cell expression data. AVAILABILITY AND IMPLEMENTATION: Our work is implemented in the pCMF R-package (https://github.com/gdurif/pCMF). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Análise de Dados , Software , Algoritmos , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Célula Única
4.
Bioinformatics ; 34(3): 485-493, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28968879

RESUMO

Motivation: The high dimensionality of genomic data calls for the development of specific classification methodologies, especially to prevent over-optimistic predictions. This challenge can be tackled by compression and variable selection, which combined constitute a powerful framework for classification, as well as data visualization and interpretation. However, current proposed combinations lead to unstable and non convergent methods due to inappropriate computational frameworks. We hereby propose a computationally stable and convergent approach for classification in high dimensional based on sparse Partial Least Squares (sparse PLS). Results: We start by proposing a new solution for the sparse PLS problem that is based on proximal operators for the case of univariate responses. Then we develop an adaptive version of the sparse PLS for classification, called logit-SPLS, which combines iterative optimization of logistic regression and sparse PLS to ensure computational convergence and stability. Our results are confirmed on synthetic and experimental data. In particular, we show how crucial convergence and stability can be when cross-validation is involved for calibration purposes. Using gene expression data, we explore the prediction of breast cancer relapse. We also propose a multicategorial version of our method, used to predict cell-types based on single-cell expression data. Availability and implementation: Our approach is implemented in the plsgenomics R-package. Contact: ghislain.durif@inria.fr. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Modelos Logísticos , Análise de Sequência de DNA/métodos , Software , Calibragem , Genômica/métodos , Genômica/normas , Análise dos Mínimos Quadrados , Análise de Sequência de DNA/normas
5.
BMC Bioinformatics ; 19(1): 314, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30189832

RESUMO

BACKGROUND: To address high-dimensional genomic data, most of the proposed prediction methods make use of genomic data alone without considering clinical data, which are often available and known to have predictive value. Recent studies suggest that combining clinical and genomic information may improve predictions. We consider here methods for classification purposes that simultaneously use both types of variables but apply dimensionality reduction only to the high-dimensional genomic ones. RESULTS: Using partial least squares (PLS), we propose some one-step approaches based on three extensions of the least squares (LS)-PLS method for logistic regression. A comparison of their prediction performances via a simulation and on real data sets from cancer studies is conducted. CONCLUSION: In general, those methods using only clinical data or only genomic data perform poorly. The advantage of using LS-PLS methods for classification and their performances are shown and then used to analyze clinical and genomic data. The corresponding prediction results are encouraging and stable regardless of the data set and/or number of selected features. These extensions have been implemented in the R package lsplsGlm to enhance their use.


Assuntos
Perfilação da Expressão Gênica , Genoma Humano , Genômica/métodos , Análise dos Mínimos Quadrados , Neoplasias/classificação , Algoritmos , Conjuntos de Dados como Assunto , Humanos , Modelos Logísticos , Neoplasias/genética
6.
Int J Med Inform ; 172: 104983, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36724730

RESUMO

OBJECTIVE: Artificial Intelligence (AI) offers potential opportunities to optimize clinical pharmacy services in community or hospital settings. The objective of this systematic literature review was to identify and analyse quantitative studies using or integrating AI for clinical pharmacy services. MATERIALS AND METHODS: A systematic review was conducted using PubMed/Medline and Web of Science databases, including all articles published from 2000 to December 2021. Included studies had to involve pharmacists in the development or use of AI-powered apps and tools.. RESULTS: 19 studies using AI for clinical pharmacy services were included in this review. 12 out of 19 articles (63.1%) were published in 2020 or 2021. Various methodologies of AI were used, mainly machine learning techniques and subsets (natural language processing and deep learning). The datasets used to train the models were mainly extracted from electronic medical records (6 studies, 32%). Among clinical pharmacy services, medication order review was the service most targeted by AI-powered apps and tools (9 studies), followed by health product dispensing (4 studies), pharmaceutical interviews and therapeutic education (2 studies). The development of these tools mainly involved hospital pharmacists (12/19 studies). DISCUSSION AND CONCLUSION: The development of AI-powered apps and tools for clinical pharmacy services is just beginning. Pharmacists need to keep abreast of these developments in order to position themselves optimally while maintaining their human relationships with healthcare teams and patients. Significant efforts have to be made, in collaboration with data scientists, to better assess whether AI-powered apps and tools bring value to clinical pharmacy services in real practice.


Assuntos
Serviços Comunitários de Farmácia , Serviço de Farmácia Hospitalar , Médicos , Humanos , Inteligência Artificial , Farmacêuticos , Hospitais
7.
Ann N Y Acad Sci ; 1067: 337-42, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16804008

RESUMO

Effects of active ingredients from topical and systemic skincare products on structure and organization of epidermis, dermal-epidermal junction (DEJ), and dermis were examined using an in vitro reconstructed skin equivalent (SE). Imedeen Time Perfection (ITP) ingredients (a mixture of BioMarine Complex, grape seed extract, tomato extract, vitamin C) were supplemented systemically into culture medium. Kinetin, an active ingredient from Imedeen Expression Line Control Serum, was applied topically. Both treatments were tested separately or combined. In epidermis, all treatments stimulated keratinocyte proliferation, showing a significant increase of Ki67-positive keratinocytes (P < 0.05). Kinetin showed a twofold increase of Ki67-positive cells, ITP resulted in a fivefold, and ITP+kinetin showed a nine-fold increase. Differentiation of keratinocytes was influenced only by kinetin since filaggrin was found only in kinetin and kinetin+ITP samples. At the DEJ, laminin 5 was slightly increased by all treatments. In dermis, only ITP increased the amount of collagen type I. Both kinetin and ITP stimulated formation of fibrillin-1 and elastin deposition. The effect of kinetin was seen in upper dermis. It stimulated not only the amount of deposited fibrillin-1 and elastin fibers but also their organization perpendicularly to the DEJ. ITP stimulated formation of fibrillin-1 in deeper dermis. In summary, the combination of topical treatment with kinetin and systemic treatment with ITP had complementary beneficial effects in the formation and development of epidermis and dermis.


Assuntos
Derme/citologia , Células Epidérmicas , Higiene da Pele , Pele Artificial , Administração Tópica , Adulto , Técnicas de Cultura de Células , Células Cultivadas , Interações Medicamentosas , Elastina/metabolismo , Feminino , Fibrilina-1 , Fibrilinas , Proteínas Filagrinas , Glicosaminoglicanos/administração & dosagem , Glicosaminoglicanos/farmacologia , Humanos , Proteínas de Filamentos Intermediários/análise , Proteínas de Filamentos Intermediários/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , Antígeno Ki-67/metabolismo , Cinetina/farmacologia , Proteínas dos Microfilamentos/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Proteínas/administração & dosagem , Proteínas/farmacologia , Pele
8.
Dalton Trans ; 41(43): 13423-8, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23007791

RESUMO

Chemoenzymatic dynamic kinetic resolution (DKR) of rac-1-phenyl ethanol into R-1-phenylethanol acetate was investigated with emphasis on the minimization of side reactions. The organometallic hydrogen transfer (racemization) catalyst was varied, and this was observed to alter the rate and extent of oxidation of the alcohol to form ketone side products. The performance of highly active catalyst [(pentamethylcyclopentadienyl)IrCl(2)(1-benzyl,3-methyl-imidazol-2-ylidene)] was found to depend on the batch of lipase B used. The interaction between the bio- and chemo-catalysts was reduced by employing physical entrapment of the enzyme in silica using a sol-gel process. The nature of the gelation method was found to be important, with an alkaline method preferred, as an acidic method was found to initiate a further side reaction, the acid catalyzed dehydration of the secondary alcohol. The acidic gel was found to be a heterogeneous solid acid.


Assuntos
Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Compostos Organometálicos/química , Catálise , Proteínas Fúngicas/química , Géis/química , Hidrogênio/química , Hidrogênio/metabolismo , Cinética , Lipase/química , Oxirredução , Álcool Feniletílico/química , Álcool Feniletílico/metabolismo , Dióxido de Silício/química
9.
Biogerontology ; 8(2): 97-109, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17028931

RESUMO

Cultured skin equivalent (SE, Mimeskin) was generated by co-culturing skin fibroblasts and keratinocytes on a collagen-glycosaminoglycan-chitosan dermal substrate. In order to examine donor age effect, fibroblasts from 19- (young) or 49- (aged) year-old females were used. Culture medium was supplemented with nutrients complex containing soy extract, tomato extract, grape seed extract, white tea extract, sodium ascorbate, tocopherol acetate, zinc gluconate and BioMarine complex. Epidermal and dermal structure and composition were examined after 42 and 60 days of culture. In untreated samples, SE generated from young fibroblasts was superior to SE from aged fibroblasts in all characteristics. Those include number and regularity of keratinocyte layers, number of keratinocytes expressing proliferation marker Ki67, content of collagen type I, fibrillin-1, elastin, and SE lifespan. Effects of nutritional supplementation were observed in SE from both young and aged fibroblasts, however, those effects were more pronounced in SE from aged fibroblasts. In epidermis, the treatment increased number of keratinocyte layers and delayed epidermal senescence. The number of cells expressing Ki67 was nine folds higher than those of controls, and was similar to that of young cell SE. In dermis, the treatment increased mRNA synthesis of collagen I, fibrillin-1 and elastin. In conclusion, skin cell donor age had major important effect on formation of reconstructed SE. Imperfections in epidermal and dermal structure and composition as well as life span in SE from aged cells can be improved by supplementation with active nutrients.


Assuntos
Envelhecimento/fisiologia , Órgãos Bioartificiais , Derme/efeitos dos fármacos , Epiderme/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Glicosaminoglicanos/farmacologia , Queratinócitos/efeitos dos fármacos , Proteínas/farmacologia , Pele Artificial , Adulto , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Derme/citologia , Derme/metabolismo , Elastina/genética , Elastina/metabolismo , Células Epidérmicas , Epiderme/metabolismo , Feminino , Fibrilina-1 , Fibrilinas , Fibroblastos/metabolismo , Expressão Gênica/efeitos dos fármacos , Glicosaminoglicanos/química , Humanos , Queratinócitos/metabolismo , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Pessoa de Meia-Idade , Proteínas/química , RNA Mensageiro/metabolismo , Regeneração/efeitos dos fármacos , Fatores de Tempo , Engenharia Tecidual/métodos
10.
Bioinformatics ; 21(7): 1104-11, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15531609

RESUMO

MOTIVATION: One important aspect of data-mining of microarray data is to discover the molecular variation among cancers. In microarray studies, the number n of samples is relatively small compared to the number p of genes per sample (usually in thousands). It is known that standard statistical methods in classification are efficient (i.e. in the present case, yield successful classifiers) particularly when n is (far) larger than p. This naturally calls for the use of a dimension reduction procedure together with the classification one. RESULTS: In this paper, the question of classification in such a high-dimensional setting is addressed. We view the classification problem as a regression one with few observations and many predictor variables. We propose a new method combining partial least squares (PLS) and Ridge penalized logistic regression. We review the existing methods based on PLS and/or penalized likelihood techniques, outline their interest in some cases and theoretically explain their sometimes poor behavior. Our procedure is compared with these other classifiers. The predictive performance of the resulting classification rule is illustrated on three data sets: Leukemia, Colon and Prostate.


Assuntos
Biomarcadores Tumorais/metabolismo , Perfilação da Expressão Gênica/métodos , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reconhecimento Automatizado de Padrão/métodos , Algoritmos , Biomarcadores Tumorais/genética , Diagnóstico por Computador/métodos , Humanos , Análise dos Mínimos Quadrados , Modelos Genéticos , Modelos Estatísticos , Proteínas de Neoplasias/genética , Neoplasias/diagnóstico , Análise de Regressão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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