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1.
J Am Chem Soc ; 141(22): 8694-8697, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31117646

RESUMO

5-Hydroxymethylcytosine (5hmC) arises from the oxidation of 5-methylcytosine (5mC) by Fe2+ and 2-oxoglutarate-dependent 10-11 translocation (TET) family proteins. Substantial levels of 5hmC accumulate in many mammalian tissues, especially in neurons and embryonic stem cells, suggesting a potential active role for 5hmC in epigenetic regulation beyond being simply an intermediate of active DNA demethylation. 5mC and 5hmC undergo dynamic changes during embryogenesis, neurogenesis, hematopoietic development, and oncogenesis. While methods have been developed to map 5hmC, more efficient approaches to detect 5hmC at base resolution are still highly desirable. Herein, we present a new method, Jump-seq, to capture and amplify 5hmC in genomic DNA. The principle of this method is to label 5hmC by the 6- N3-glucose moiety and connect a hairpin DNA oligonucleotide carrying an alkyne group to the azide-modified 5hmC via Huisgen cycloaddition (click) chemistry. Primer extension starts from the hairpin motif to the modified 5hmC site and then continues to "land" on genomic DNA. 5hmC sites are inferred from genomic DNA sequences immediately spanning the 5-prime junction. This technology was validated, and its utility in 5hmC identification was confirmed.


Assuntos
5-Metilcitosina/análogos & derivados , Genômica , 5-Metilcitosina/metabolismo , DNA/química , DNA/genética , DNA/metabolismo , Técnicas de Amplificação de Ácido Nucleico
2.
J Stat Comput Simul ; 89(5): 815-830, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32981982

RESUMO

This article focuses on the clustering problem based on Dirichlet process (DP) mixtures. To model both time invariant and temporal patterns, different from other existing clustering methods, the proposed semi-parametric model is flexible in that both the common and unique patterns are taken into account simultaneously. Furthermore, by jointly clustering subjects and the associated variables, the intrinsic complex shared patterns among subjects and among variables are expected to be captured. The number of clusters and cluster assignments are directly inferred with the use of DP. Simulation studies illustrate the effectiveness of the proposed method. An application to wheal size data is discussed with an aim of identifying novel temporal patterns among allergens within subject clusters.

3.
Biomed Res Int ; 2022: 2863379, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35655485

RESUMO

This research was developed to accurately evaluate the unstable fractures of thoracolumbar before and after surgery and discuss the treatment timing and methods. Three-dimensional (3D) finite element method was adopted to construct the T12-L5 segment model of human body. The efficiency of percutaneous kyphoplasty (PKP) and percutaneous vertebroplasty (PVP), two commonly used internal fixation procedures, was retrospectively compared. A total of 150 patients with chest fracture who received PKP or PVP surgery in our hospital, and 104 patients with the same symptoms who received conservative treatment were collected and randomly rolled into PVP group (75 cases), PKP group (75 cases), and control group (104 cases). Visual analog scale (VAS) score and Oswestry disability index (ODI) of patients were collected before and after surgery and 2, 12, and 24 months after surgery. Then, the anterior and central height of the patient's cone and the kyphosis angle were calculated by X-ray. Lumbar minimally invasive fusion system and lumbar pedicle screw rod system were established by computer-aided design (CAD), and the biomechanical characteristics were analyzed. The results showed that there was no substantial difference in VAS score and ODI score between PKP and PVP (P > 0.05), but they were higher than those of the control group (P < 0.05). The anterior edge and middle height of vertebra in the two groups were higher than those in control group (P < 0.05), and the increase in PKP group was more substantial (P < 0.05). The kyphosis of the two groups was smaller than that of the control group (P < 0.05), and the decrease of the kyphosis of the PKP group was more substantial (P < 0.05). In summary, the thoracolumbar segment model established by 3D finite element method was an effective model, and it was verified on patients that both PKP and PVP could achieve relatively satisfactory efficacy. The implantation of the new internal fixation system had no obvious effect on the lumbar movement. This work provided a novel idea and method for the treatment of senile thoracolumbar unstable fracture, as well as experimental data of biomechanics for the operation of senile unstable fracture.


Assuntos
Cifose , Anormalidades Musculoesqueléticas , Fraturas da Coluna Vertebral , Idoso , Transplante Ósseo , Humanos , Cifose/diagnóstico por imagem , Cifose/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/lesões , Vértebras Lombares/cirurgia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/lesões , Vértebras Torácicas/cirurgia
4.
PLoS One ; 16(2): e0246935, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33617564

RESUMO

In this study, a new flexible lifetime model called Burr XII moment exponential (BXII-ME) distribution is introduced. We derive some of its mathematical properties including the ordinary moments, conditional moments, reliability measures and characterizations. We employ different estimation methods such as the maximum likelihood, maximum product spacings, least squares, weighted least squares, Cramer-von Mises and Anderson-Darling methods for estimating the model parameters. We perform simulation studies on the basis of the graphical results to see the performance of the above estimators of the BXII-ME distribution. We verify the potentiality of the BXII-ME model via monthly actual taxes revenue and fatigue life applications.


Assuntos
Distribuições Estatísticas , Simulação por Computador , Análise dos Mínimos Quadrados , Funções Verossimilhança , Modelos Estatísticos
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