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1.
Comput Methods Programs Biomed ; 220: 106827, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35500505

RESUMEN

BACKGROUND: Recent attempts on adopting artificial intelligence algorithm on coronary diagnosis had limitations on data quantity and quality. While most of previous studies only used vessel image as input data, flow features and biometric features should be also considered. Moreover, the accuracy should be optimized within gray zone as the purpose is to decide stent insertion with estimated fractional flow reserve. OBJECTIVES: The main purpose of this study is to develop an artificial intelligence-based coronary vascular diagnosis system focused on performance in the gray zone, from CT image extraction to FFR estimation. Three main issues should be considered for an algorithm to be used for pre-screening: algorithm optimization in the gray zone, minimization of labor during image processing, and consideration of flow and biometric features. This paper introduces a full FFR pre-screening system from automatic image extraction to an algorithm for estimating the FFR value. METHOD: The main techniques used in this study are an automatic image extraction algorithm, lattice Boltzmann method based computational fluid dynamics analysis of a synthetic model and patient data, and an AI algorithm optimization. For feature extraction, this study focused on an automatic process to reduce manual labor. The algorithm consisted of two steps: the first algorithm calculates flow features from geometrical features, and the second algorithm estimates the FFR value from flow features and patient biometric features. Algorithm selection, outlier elimination, and k-fold selection were included to optimize the algorithm. CONCLUSION: Eight types of algorithms including two neural network models and six machine learning models were optimized and tested. The random forest model shows the highest performance before optimization, whereas the multilayer perceptron regressor shows the highest gray zone accuracy after optimization.


Asunto(s)
Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Algoritmos , Inteligencia Artificial , Biometría , Angiografía Coronaria/métodos , Hemodinámica , Humanos , Valor Predictivo de las Pruebas , Estudios Retrospectivos
2.
Plasmid ; 67(1): 35-43, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22133745

RESUMEN

The pCB42 plasmid from Leuconostoc citreum CB2567, a strain isolated from kimchi, was characterized, and a shuttle vector for Escherichia coli and lactic acid bacteria (LAB) was constructed. The pCB42 plasmid has a circular structure of 4312bp, a low G+C content, and no single-stranded DNA intermediates during replication, which indicates that pCB42 replicates via the theta-type replication mechanism. In silico analysis of this plasmid revealed 6 open reading frames: 1 transposase gene, 1 DNA-binding gene, 2 putative replication genes, and 2 unknown genes. The fragment encompassing ORF5 contains a functional plasmid replicon. This plasmid was capable of replicating in various LAB, including L. citreum, L. mesenteroides, Lactobacillus plantarum, Lb. reuteri, Lactococcus lactis, Streptococcus thermophilus, Weissella confusa, and Oenococcus oeni. The LAB-E. coli shuttle vector was constructed by ligating pCB42 and pEK104, and the resulting shuttle vector, pLeuCM42, showed a high segregational stability in L. citreum CB2567 after 100 generations of cell division. By using this shuttle vector, the ß-gal gene from Lb. plantarum was successfully expressed in the host strain, L. citreum CB2567. The pLeuCM42 shuttle vector can serve as a useful gene-delivery and expression tool for the genetic study or metabolic engineering of various strains of LAB.


Asunto(s)
Vectores Genéticos/genética , Lactobacillaceae/genética , Lactobacillaceae/aislamiento & purificación , Leuconostoc/genética , Leuconostoc/aislamiento & purificación , Plásmidos/genética , Replicón/genética , Verduras/microbiología , Secuencia de Aminoácidos , Secuencia de Bases , Western Blotting , Replicación del ADN , ADN Bacteriano/genética , ADN de Cadena Simple/genética , Lactobacillaceae/clasificación , Lactobacillaceae/metabolismo , Leuconostoc/metabolismo , Ingeniería Metabólica , Datos de Secuencia Molecular , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Transformación Bacteriana , beta-Galactosidasa/metabolismo
3.
Biotechnol Lett ; 31(11): 1783-8, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19618275

RESUMEN

To develop a gene expression system for Leuconostoc genus, construction of expression vector and expression of a heterologus protein in Leuconostoc was performed. Alpha-amylase gene from Lactobacillus amylovorus was cloned into a Leuconostoc cloning vector, pLeuCM, with its own signal peptide. pLeuCMamy was introduced into Leuconostoc citreum CB2567 and a successful expression of alpha-amy gene was confirmed by enzyme activity assays. About 90% of alpha-amylase activity was detected in the culture broth, revealing most of expressed alpha-amylase was secreted out cells. The signal sequence of alpha-amy gene is a good candidate for the secretion of heterologous protein by using Leuconostoc host-vector system.


Asunto(s)
Lactobacillus acidophilus/enzimología , Leuconostoc/metabolismo , alfa-Amilasas/metabolismo , Clonación Molecular , Genes Bacterianos , Lactobacillus acidophilus/genética , Leuconostoc/citología , Leuconostoc/crecimiento & desarrollo , Plásmidos/genética , Mapeo Restrictivo , Análisis de Secuencia de ADN , Transformación Genética , alfa-Amilasas/genética
4.
Biochem Biophys Res Commun ; 364(1): 157-62, 2007 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-17936248

RESUMEN

Paraoxonase-1 (PON1) is an enzyme associated with HDL in blood and it is considered as an anti-oxidant factor due to its capability to prevent lipid oxidation. In vivo mouse studies also have shown that PON1 is one of the genetic risk factors contributing to atherosclerosis. In this study, we evaluated the serum PON1 activities of sex-age matched Korean healthy control and ischemic stroke patients, and investigated the association of PON1 activity with other metabolic parameters. Statistical analyses revealed that PON1 activity and HDL_cholesterol (HDL_C) in stroke patients were significantly decreased when compared with those of healthy control. Additionally, PON1 activity was negatively correlated with age, whereas it was positively correlated with HDL_C in a stroke group. Overall, the results of this study indicated that decreased serum PON1 activity should be considered as a risk factor for ischemic stroke in Koreans.


Asunto(s)
Arildialquilfosfatasa/sangre , Accidente Cerebrovascular/etiología , Anciano , HDL-Colesterol/sangre , Femenino , Humanos , Corea (Geográfico)/epidemiología , Masculino , Persona de Mediana Edad , Factores de Riesgo
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