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1.
J Appl Math Comput ; 69(2): 2217-2237, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36590452

RESUMEN

A stochastic SIQS model via isolation with regime-switching is studied in this paper. The range of positive solution of the model is presented. Threshold to determine extinction and invariant measure is obtained by a new technique, which can be seen as the sufficient and almost necessary condition. Meantime, a value to judge the existence of stationary distribution is acquired by constructing the suitable hybrid Lyapunov function. Two values are proved to be consistent. Several examples are enumerated to test the theoretical results.

2.
Biochem Biophys Res Commun ; 499(2): 112-119, 2018 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-29470982

RESUMEN

Traumatic brain injury (TBI) is a leading cause of disability and mortality in young adults worldwide. The pathophysiology is not fully understood. Programmed necrosis (necroptosis) is a newly identified mechanism of cell death combining features of both apoptosis and necrosis. Receptor-interacting protein 3 (RIP3) plays an important role in programmed necrosis. However, the effect of RIP3-related pathway in TBI is little to be known. We attempted to explore the significance of RIP3 in regulating TBI in vivo. Significantly, TBI induced over-expression of RIP3 in the hippocampus of mice, as well as RIP1 and phosphorylated mixed lineage kinase domain-like protein (MLKL). Mice after TBI exhibited cognitive dysfunction and activation of glia cells, which were significantly attenuated by RIP3-knockout (KO). Moreover, inflammation and oxidative stress in hippocampus were markedly induced by TBI in wild type (WT) mice. Of note, the reduction of pro-inflammatory cytokines and oxidants was observed in RIP3-deficient mice, which was linked to the blockage of NLR pyrin domain containing 3 (NLRP3)/apoptosis-associated speck-like protein containing a CARD (ASC)/Caspase-1 and kelch-like ECH-associated protein 1 (Keap 1) pathways. Further, TBI induced hippocampus apoptosis, evidenced by the increase of cleaved Caspase-8/-3 and poly (ADP)-ribose polymerase (PARP) in WT mice, whereas being decreased by RIP3-knockout. In addition, RIP3 knockout led to phosphorylation of AMP-activated protein kinase α (AMPKα) in hippocampus of mice after TBI. And of note, the in vitro findings indicated that RIP3-ablation attenuated oxidative stress, inflammation and apoptosis in astrocytes, which was dependent on AMPKα activation. Together, suppressing RIP3 might be served as a therapeutic target against brain injury through inhibiting inflammation, oxidative stress and apoptosis.


Asunto(s)
Adenilato Quinasa/metabolismo , Apoptosis , Lesiones Traumáticas del Encéfalo/enzimología , Lesiones Traumáticas del Encéfalo/prevención & control , Inflamación/patología , Estrés Oxidativo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/deficiencia , Transducción de Señal , Animales , Astrocitos/enzimología , Astrocitos/patología , Lesiones Traumáticas del Encéfalo/patología , Lesiones Traumáticas del Encéfalo/fisiopatología , Cognición , Constricción Patológica , Eliminación de Gen , Hipocampo/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo
3.
Eur J Med Res ; 28(1): 564, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38053193

RESUMEN

OBJECTIVE: To explore the surgical techniques, advantages, and disadvantages of neuroendoscopic telovelar approach in the treatment of brainstem and fourth ventricle lesions. METHODS: The clinical data of 5 patients treated by neuroendoscopic telovelar approach from March 2020 to March 2022 were analyzed retrospectively. RESULTS: Among the 5 patients, there were 3 cavernous hemangiomas in pontine arm and 2 tumors in brainstem and fourth ventricle. All patients could successfully complete the operation, and 4 patients recovered well, other 1 patient discharged automatically for serious complications of other systems after the operation. CONCLUSION: The telovelar approach has gained popularity as a safe and effective strategy for lesions in fourth ventricular and brainstem. However, without removing the posterior arch of the atlas, it is difficult to enter the upper part of the fourth ventricle under a microscope. Transcranial neuroendoscopy can effectively compensate for the shortcomings of microscopy, whether used as an auxiliary measure for microsurgery or alone with proficient endoscopic techniques, it will provide greater application in minimally invasive surgery for fourth ventricle and brainstem lesions. By utilizing the excellent degree of freedom of transcranial neuroendoscopy, there is no need to open the posterior arch of the atlas, making the surgery more minimally invasive. However, the sample size of this study is small, and it was completed under the very mature neuroendoscopic technology of our team. Its general safety and practicality still require extensive clinical research validation.


Asunto(s)
Neuroendoscopía , Humanos , Neuroendoscopía/métodos , Cuarto Ventrículo/cirugía , Procedimientos Neuroquirúrgicos/efectos adversos , Estudios Retrospectivos , Tronco Encefálico/cirugía
4.
Am J Transl Res ; 14(4): 2617-2624, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35559390

RESUMEN

OBJECTIVE: Aneurysmal subarachnoid hemorrhage (aSAH) is an acute disease with rapid progression and critical condition. The most common complication of aSAH is cerebral vasospasm (CVS). Patients are predisposed to severe cerebral ischemia, brain injury, or even death if effective measures are not taken in time to relieve symptoms. This study mainly determines the effect of nimodipine (NM) combined with fasudil on vascular endothelial function (VEF) and inflammatory factors (IFs) in patients with aSAH induced CVS. METHODS: The clinical data of 77 patients with aSAH induced CVS treated in the Renmin Hospital of Wuhan University from March 2019 to June 2020 were analyzed retrospectively. Based on different drug therapies, patients receiving NM monotherapy were assigned to the control group (n=32), while those treated with NM combined with fasudil were included in the observation group (n=45), both received two consecutive weeks of treatment. The two arms were compared regarding the following items: clinical efficacy, average blood flow velocities (BFVs) of anterior, posterior and middle cerebral arteries, serum IFs, levels of vascular endothelial growth factor (VEGF), ET-1 and CGRP, cognitive function (Montreal Cognitive Assessment Scale, MOCA), activities of daily living (Bathel index), and adverse reactions. RESULTS: The overall response rate of the observation group was significantly higher than that of the control group (P<0.05). After treatment, the BFVs of the anterior, posterior and middle cerebral arteries in the observation group decreased significantly compared with the control group (P<0.05). ET-1 and VEGF decreased in both groups, while CGRP increased, with more significant changes in the observation group (P<0.05). Serum IFs reduced in both arms, with more evident reductions in the observation group (P<0.05). The MOCA score and Barthel index increased statistically in both arms and were higher in the observation group compared with the control group (P<0.05). There was no significant difference in the total incidence of adverse reactions between the observation group and the control group (P>0.05). CONCLUSIONS: NM combined with fasudil in the treatment of aSAH induced CVS can effectively improve the VEF, alleviate IFs, and enhance the cognitive function and quality of life of patients, which is worth popularizing in clinic.

5.
Biomed Res Int ; 2022: 1037525, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36330459

RESUMEN

Objective: Angiogenesis is one of the therapeutic targets of cerebral infarction. Long noncoding RNAs (lncRNAs) can regulate the pathological process of angiogenesis following ischemic stroke. Taurine-upregulated gene 1 (TUG1), an lncRNA, is correlated to ischemic stroke. We intended to determine the effect of TUG1 on angiogenesis following an ischemic stroke. Materials and Methods: Middle cerebral artery occlusion (MCAO) was adopted to build a focal ischemic model of the rat brain, and pcDNA-TUG1 and miR-26a mimics were injected into rats. Neurological function was estimated through modified neurological severity scores. The volume of focal brain infarction was calculated through 2,3,5-triphenyltetrazolium chloride staining. The level of TUG1 and miR-26a was measured by PCR. The expression of vascular endothelial growth factor (VEGF) and CD31 was checked using immunohistochemistry and western blot. The correlation between miR-26a and TUG1 was verified through a luciferase reporter assay. Results: TUG1 increased noticeably while miR-26a was markedly reduced in MCAO rats. Overexpression of miR-26a improved neurological function recovery and enhanced cerebral angiogenesis in MCAO rats. TUG1 overexpression aggravated neurological deficits and suppressed cerebral angiogenesis in MCAO rats. Bioinformatics analysis revealed that miR-26a was one of the predicted targets of TUG1. Furthermore, TUG1 combined with miR-26a to regulate angiogenesis. TUG1 overexpression antagonized the role of miR-26a in neurological recovery and angiogenesis in MCAO rats. Conclusions: TUG1/miR-26a, which may act as a regulatory axis in angiogenesis following ischemic stroke, can be considered a potential target for cerebral infarction therapy.


Asunto(s)
Accidente Cerebrovascular Isquémico , MicroARNs , ARN Largo no Codificante , Ratas , Animales , MicroARNs/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Taurina , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Neovascularización Patológica/genética , Infarto de la Arteria Cerebral Media/genética
6.
Sci Rep ; 12(1): 19258, 2022 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-36357434

RESUMEN

To explore the clinical advantages of 3D Slicer combined with Sina/MosoCam multimodal system in preoperative planning of brain lesions surgery. By collecting the data of brain lesions patients undergoing craniotomy under the preoperative positioning of 3D Slicer combined Sina/MosoCam multimodal system in the people's Hospital of Wuhan University from January 2021 to October 2021, the preoperative planning of patients was introduced, and the size of surgical bone window, operation time, preoperative and postoperative neurological dysfunction were counted. We collected the case data of 35 patients who were reconstructed by 3D Slicer and located by Sina/MosoCam projection. There were 14 cases of malignant tumors (7 cases of glioma, 2 cases of diffuse large B-cell lymphoma, 5 cases of metastatic cancer) and 21 cases of benign tumors (17 cases of meningioma, 1 case of central neurocytoma, 2 cases of cavernous hemangioma and 1 case of arachnoid cyst). All 35 patients were located accurately before operation, the lesions were found quickly during operation, and the postoperative imaging data confirmed that the lesions were removed completely, of which 28 cases (80%) had significantly improved neurological symptoms one month after operation. 3D Slicer combined with Sina/MosoCam multimodal system has many advantages, such as simple and easy to learn, convenient operation, accurate positioning and free. It is considered to be a new technology that is practical, reliable, convenient for diagnosis and preoperative planning. It is suitable for popularization and use in neurosurgery and other operating rooms of all medical institutions.


Asunto(s)
Glioma , Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/diagnóstico por imagen , Meningioma/cirugía , Glioma/cirugía , Procedimientos Neuroquirúrgicos/métodos , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/cirugía , Encéfalo , Imagenología Tridimensional , Estudios Retrospectivos
7.
Sci Rep ; 12(1): 20421, 2022 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-36443477

RESUMEN

To explore the clinical advantages of 3D-Slicer + 3D printing guide combined with transcranial neuroendoscopic in minimally invasive neurosurgery. By collecting the datum of patients who underwent craniotomy under 3D-Slicer + 3D printing guide plate positioning combined with transcranial neuroendoscopic in our hospital from October 2021 to February 2022, this paper introduces the accurate planning and positioning lesions of patients before operation and the minimally invasive operation of intraoperative neuroendoscopic and analyses clinical data such as lesion size and surgical bone window size. We collected the case datum of 16 patients who underwent craniocerebral surgery with 3D-Slicer + 3D printing guide combined with transcranial neuroendoscopic, including 5 males and 11 females, aged 46-76 years, including 6 brain tumors (3 meningiomas, 1 glioblastoma, 2 lung cancer brain metastases), 2 cavernous hemangioma, 7 hydrocephalus and 1 chronic subdural hematoma. The lesions of the 16 patients were located accurately before operation and the target areas were reached quickly during operation. Postoperative imaging datum confirmed that the lesions was removed fully, and the ventricular end of shunt tube was in good position. The technology of 3D-Slicer + 3D printing guide plate combined with transcranial neuroendoscopic is not difficult, which has many advantages such as inexpensive equipment, simple operation, easy learning, accurate positioning, and minimally invasive surgery. It is considered to be a practical technology that is feasible, reliable, convenient for diagnosis, preoperative planning and minimally invasive surgery. It is suitable for promotion in neurosurgery and other surgical departments of all medical institutions.


Asunto(s)
Neoplasias Encefálicas , Neoplasias Meníngeas , Neuroendoscopía , Neurocirugia , Femenino , Masculino , Humanos , Procedimientos Neuroquirúrgicos , Impresión Tridimensional , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía
8.
J Healthc Eng ; 2021: 5679665, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34737849

RESUMEN

This study was to use the partial differential mathematical model to analyze the magnetic resonance imaging (MRI) images of cerebral ischemia-reperfusion injury (CIRI) and to dynamically observe the role of L-theanine in CIRI based on this. 30 patients with cerebral ischemia in a hospital in a certain area were selected and divided into a cerebral ischemia group and a L-theanine treatment group. The two groups of patients were examined by MRI within 48 hours, and the relative apparent diffusion coefficient (rADC) of the cerebral ischemic part of the patients was determined. The partial differential mathematical model was used for data processing to obtain the function of cerebral ischemia time and infarct area, and the data of patients in the cerebral ischemia group and L-theanine treatment group were compared and analyzed. The results showed that the partial differential mathematical model could effectively analyze the linear relationship between the rADC value and time in the treatment of CIRI using L-theanine. The rADC values of the four points of interest in the L-theanine treatment group all increased with time, and there was a positive correlation between the variables X and Y. In observing the efficacy indicators of L-theanine, the L-theanine treatment group showed a significant advantage in the neurospecific enolase (NSE) content compared with the cerebral ischemia group (P < 0.01), and the neurological function score of the L-theanine treatment group gradually decreased and showed a statistically obvious difference on the 7th day of treatment (P < 0.05). In summary, it was verified in this study that the role of L-theanine in the treatment of CIRI was of a great and positive significance for the subsequent treatment of patients with cerebral ischemia, providing reliable theoretical basis and data basis for clinical treatment of CIRI.


Asunto(s)
Isquemia Encefálica , Glutamatos/uso terapéutico , Daño por Reperfusión , Adulto , Anciano , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/tratamiento farmacológico , Imagen de Difusión por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Modelos Teóricos , Daño por Reperfusión/diagnóstico por imagen
9.
Arq Neuropsiquiatr ; 77(6): 375-380, 2019 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-31314838

RESUMEN

OBJECTIVE: To analyze the risk factors and prognosis related to early post-traumatic epilepsy (EPTE). METHODS: One hundred and eighty-six patients with traumatic brain injury were enrolled. Their full clinical data were collected. Single factor analysis and logistic regression analysis of risk factors related to EPTE were performed. The prognosis of patients was determined. RESULTS: Single factor analysis showed that there were significant differences of age (p = 0.011), epilepsy history (p < 0.001), injury site (p = 0.004), injury type (p < 0.001) and injury degree (p < 0.001) between the EPTE group (40 patients) and non-EPTE group (146 patients). Logistic regression analysis showed that the injury site, injury type and injury degree were the main risk factors for EPTE. The odds ratio values of injury site, injury type and injury degree were 1.977 (1.473-2.679), 2.096 (1.543-2.842) and 2.376 (1.864-3.609), respectively. The logistic regression equation was P = Exp (-1.473 + 0.698 × injury site + 0.717 × injury type + 0.935 × injury degree). The sensitivity and specificity of injury site, injury type and injury degree for predicting EPTE were 79.2% and 80.5%, 78.9% and 85.7% and 84.2% and 81.0%, respectively. The analysis of prognosis showed that the Glasgow Outcome Scale/Activity of Daily Living Scale scores in the EPTE group were significantly lower than those in non-EPTE group (p < 0.05). CONCLUSIONS: Injury site, injury type and injury degree are the main risk factors for EPTE. The prognosis of patients with traumatic brain injury can be affected by EPTE.


Asunto(s)
Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/terapia , Epilepsia Postraumática/etiología , Epilepsia Postraumática/terapia , Adulto , Análisis Factorial , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Índices de Gravedad del Trauma , Adulto Joven
10.
Comput Math Methods Med ; 2018: 7325938, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30622626

RESUMEN

Similarity measure is an important tool in multiple criteria decision-making problems, which can be used to measure the difference between the alternatives. In this paper, some new similarity measures of single-valued neutrosophic sets (SVNSs) and interval-valued neutrosophic sets (IVNSs) are defined based on the Euclidean distance measure, respectively, and the proposed similarity measures satisfy the axiom of the similarity measure. Furthermore, we apply the proposed similarity measures to medical diagnosis decision problem; the numerical example is used to illustrate the feasibility and effectiveness of the proposed similarity measures of SVNSs and IVNSs, which are then compared to other existing similarity measures.


Asunto(s)
Toma de Decisiones Clínicas/métodos , Diagnóstico por Computador/métodos , Lógica Difusa , Algoritmos , Biología Computacional , Diagnóstico por Computador/estadística & datos numéricos , Estudios de Factibilidad , Humanos , Conceptos Matemáticos
11.
Springerplus ; 5(1): 1980, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27917351

RESUMEN

This paper considers the distribution of some extremum on the risk process whose income depend on the current reserve. We first construct the defective renewal sequence and obtain the density function of them. By the presented renewal measure and the strong Markov property, the distribution of the first hitting time is obtained explicitly. Then, the ruin probability and the probability that the surplus process less than x is obtained. Furthermore, the distribution of supreme profits before ruin, the joint distributions of the supreme profit and the deficit before the time of the surplus process first up-crossing level zero after ruin, and the joint distributions of the supreme profit and the deficit before the surplus process leave zero ultimately are derived. Finally, the exact calculating results for them are obtained when the individual claim amounts in the compound Poisson risk model are exponentially distributed.

12.
Int J Clin Exp Med ; 8(7): 11456-62, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26379963

RESUMEN

The aim of this study was to investigate the surgical method of hypertensive intracerebral hemorrhage (HIH) and how to control the postoperative blood pressure. 96 HIH patients were performed the craniotomic hematoma dissection (CHD) and the hematoma-cavity drilling drainage (HCDD), respectively. Meanwhile, the intracranial pressure and mean arterial pressure of each patient were continuously monitored for 7 days, the postoperative 1(st), 3(rd), 7(th) and 14(th)-day average flow velocities and pulsatility indexes of the bilateral middle cerebral arteries were monitored. CHD exhibited the significant difference in the long-term quality of life (ADL classification 6 months later) of patients with hematoma >50 ml than HCDD; furthermore, the postoperative 1(st), 3(rd), 7(th) and 14(th)-day TCD parameter analysis revealed that CHD exhibited better results in relieving the intracranial pressure and improving the cerebral blood flow than HCDD, and the postoperative ICP and MAP monitoring towards all patients could effectively control the blood pressure and prevent the further bleeding. The patients with hematoma >50 ml should choose CHD, and all HIH patients should be routinely performed the ICP and MAP monitoring.

13.
Arq. neuropsiquiatr ; 77(6): 375-380, June 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1011359

RESUMEN

ABSTRACT Objective To analyze the risk factors and prognosis related to early post-traumatic epilepsy (EPTE). Methods One hundred and eighty-six patients with traumatic brain injury were enrolled. Their full clinical data were collected. Single factor analysis and logistic regression analysis of risk factors related to EPTE were performed. The prognosis of patients was determined. Results Single factor analysis showed that there were significant differences of age (p = 0.011), epilepsy history (p < 0.001), injury site (p = 0.004), injury type (p < 0.001) and injury degree (p < 0.001) between the EPTE group (40 patients) and non-EPTE group (146 patients). Logistic regression analysis showed that the injury site, injury type and injury degree were the main risk factors for EPTE. The odds ratio values of injury site, injury type and injury degree were 1.977 (1.473-2.679), 2.096 (1.543-2.842) and 2.376 (1.864-3.609), respectively. The logistic regression equation was P = Exp (-1.473 + 0.698 × injury site + 0.717 × injury type + 0.935 × injury degree). The sensitivity and specificity of injury site, injury type and injury degree for predicting EPTE were 79.2% and 80.5%, 78.9% and 85.7% and 84.2% and 81.0%, respectively. The analysis of prognosis showed that the Glasgow Outcome Scale/Activity of Daily Living Scale scores in the EPTE group were significantly lower than those in non-EPTE group (p < 0.05). Conclusions Injury site, injury type and injury degree are the main risk factors for EPTE. The prognosis of patients with traumatic brain injury can be affected by EPTE.


RESUMO Objetivo Analisar os fatores de risco e prognóstico relacionados à epilepsia pós-traumática precoce (EPTE). Métodos Cento e oitenta e seis pacientes com lesão cerebral traumática foram incluídos. Seus dados clínicos completos foram coletados. A análise fatorial única e a análise de regressão logística dos fatores de risco relacionados à EPTE foram realizadas. O prognóstico dos pacientes foi observado. Resultados A análise fatorial única mostrou que houve diferenças significativas de idade (p = 0,011), história de epilepsia (p < 0,001), local da lesão (p = 0,004), tipo de lesão (p < 0,001) e grau de lesão (p < 0,001) entre o grupo EPTE (40 casos) e o grupo não-EPTE (146 casos), respectivamente. A análise de regressão logística mostrou que o local da lesão, tipo de lesão e grau de lesão foram os principais fatores de risco para EPTE. Os valores de razões de chance do local da lesão, tipo de lesão e grau de lesão foram 1.977 (1.473-2.679), 2.096 (1.543-2.842) e 2.376 (1.864-3.609), respectivamente. A equação de regressão logística foi P = Exp (-1,473 + 0,698 × local de lesão + 0,717 × tipo de lesão + 0,935 × grau de lesão). A sensibilidade e especificidade do local da lesão, tipo de lesão e grau de lesão para a predição da EPTE foram de 79,2% e 80,5%, 78,9% e 85,7% e 84,2% e 81,0%, respectivamente. A análise do prognóstico mostrou que o escore da Escala de Desfechos de Glasgow / Atividade de Vida Diária no grupo EPTE foi significativamente menor do que no grupo não-EPTE (P <0,05). Conclusões O local da lesão, tipo de lesão e grau de lesão são os principais fatores de risco para EPTE. A EPTE pode afetar o prognóstico de pacientes com lesão cerebral traumática.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Adulto Joven , Epilepsia Postraumática/etiología , Epilepsia Postraumática/terapia , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/terapia , Pronóstico , Modelos Logísticos , Índices de Gravedad del Trauma , Estudios Retrospectivos , Factores de Riesgo , Curva ROC , Análisis Factorial , Medición de Riesgo
14.
J Genet Genomics ; 35(3): 183-8, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18355762

RESUMEN

An entropy-based statistic T(PE) has been proposed for genomic association study for disease-susceptibility locus. The statistic T(PE) may be directly adopted and/or extended to quantitative-trait locus (QTL) mapping for quantitative traits. In this article, the statistic T(PE) was extended and applied to quantitative trait for association analysis of QTL by means of selective genotyping. The statistical properties (the type I error rate and the power) were examined under a range of parameters and population-sampling strategies (e.g., various genetic models, various heritabilities, and various sample-selection threshold values) by simulation studies. The results indicated that the statistic T(PE) is robust and powerful for genomic association study of QTL. A simulation study based on the haplotype frequencies of 10 single nucleotide polymorphisms (SNPs) of angiotensin-I converting enzyme genes was conducted to evaluate the performance of the statistic T(PE) for genetic association study.


Asunto(s)
Entropía , Predisposición Genética a la Enfermedad , Genómica/métodos , Sitios de Carácter Cuantitativo , Ligamiento Genético , Marcadores Genéticos/genética , Estudio de Asociación del Genoma Completo , Haplotipos , Modelos Genéticos , Polimorfismo de Nucleótido Simple , Renina/genética , Reproducibilidad de los Resultados
15.
J Genet Genomics ; 34(4): 373-80, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17498636

RESUMEN

By comparing the entropy and conditional entropy in a marker, an entropy-based index for fine-scale linkage-disequilibrium gene mapping is presented using high-density marker maps in extreme samples for quantitative trait. The entropy-based index is the function of LD between the marker and the trait locus and does not depend on marker allele frequencies across the loci. It is parallel to Hardy-Weinberg disequilibrium (HWD) measure for QTL fine mapping, but its power of fine mapping QTL is higher than that of HWD measure. Through simulations, the fine mapping performance of this entropy-based index is investigated extensively under various genetic parameters. The results show that the indices presented here are both robust and powerful.


Asunto(s)
Mapeo Cromosómico/métodos , Entropía , Sitios de Carácter Cuantitativo/genética , Simulación por Computador , Marcadores Genéticos , Desequilibrio de Ligamiento , Modelos Genéticos , Probabilidad
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