Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
J Adv Nurs ; 79(1): 332-342, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36300715

RESUMO

AIM: To explore why young- and middle-aged adults ignore prodromal myocardial infarction symptoms from a life course and sociocultural perspective. DESIGN: A qualitative descriptive study. METHODS: We applied purposeful sampling to recruit participants from a tertiary hospital in Guangzhou from July to November 2021. Face-to-face interviews were performed. Interviews were audio-recorded, transcribed verbatim and analysed using thematic analysis methods. RESULTS: Twenty-four young- and middle-aged adults diagnosed with acute myocardial infarction participated in this study. Analysis revealed three main themes: I'm still young, it will not happen to me; to be somebody and different roles, multiple pressures. Age-related self-confidence led to inappropriate perceptions and responses to prodromal symptoms among young- and middle-aged adults. These individuals strived to align their behaviours and attention with social expectations and self-expectations, underestimating the importance of perceiving the warning signs of acute myocardial infarction and seeking medical treatment. Pressure from social roles also prevented them from paying enough attention to prodromal symptoms. CONCLUSION: Targeted social support, public education and technologies should be provided to these individuals since they are pillars of the family and society. We also highlight how nurses can function these strategies appropriately. IMPACTS: This study contributes to a better understanding of the neglect of prodromal symptoms among young- and middle-aged adults. Its results enhance our understanding of the perception of and coping with prodromal symptoms among this population, which will help avoid the burden caused by acute myocardial infarction. PATIENT OR PUBLIC CONTRIBUTION: The patients involved in our study shared their experiences and insights to provide new perspectives regarding the neglect of prodromal myocardial infarction symptoms among young- and middle-aged adults.


Assuntos
Infarto do Miocárdio , Sintomas Prodrômicos , Pessoa de Meia-Idade , Adulto , Humanos , Infarto do Miocárdio/diagnóstico , Pesquisa Qualitativa
2.
J Clin Nurs ; 32(21-22): 7891-7908, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37353965

RESUMO

AIMS: To describe the experiences and perceptions of acute myocardial infarction (AMI) patients with a prolonged decision-making phase of treatment-seeking. BACKGROUND: Previous attempts to reduce the treatment-seeking time of AMI have been less than optimal. Due to the coronavirus disease 2019 (COVID-19) pandemic, the situation of prehospital delay is possibly worse. Decisions to seek treatment are influenced by multiple factors and need individualised interventions. Understanding patients' external and internal experiences and psychological perceptions is essential. DESIGN: Meta-synthesis. DATA SOURCES: We searched PubMed, Embase, Cochrane Library, Web of Science, Scopus and four Chinese databases from inception to April 2022. METHODS: We screened the retrieved articles with predetermined inclusion and exclusion criteria, and reviewed articles using Thomas and Harden's (BMC Medical Research Methodology, 2008 8, 45) qualitative thematic synthesis approach. The Joanna Briggs Institute critical appraisal tool for qualitative research was used to assess the quality of studies. RESULTS: Twenty-one studies were included, identifying four themes and nine sub-themes. The four primary themes were difficulty recognising and attributing symptoms, attempt to act, unwillingness to change and self-sacrifice. CONCLUSION: Deciding to seek treatment is a complex social and psychological process, which needs comprehensive interventions considering personal and sociocultural factors and factors related to the COVID-19 pandemic. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Details of interventions for decisions to seek treatment in AMI patients need to be further designed and evaluated. IMPACT: Results would help healthcare professionals to implement individualised management of decision-making of treatment-seeking among AMI patients, and improve medical records of patients' prehospital experiences. REPORTING METHOD: The Preferred Reporting Items for Systematic Reviews 2020 checklist was used to report the findings. PATIENT OR PUBLIC CONTRIBUTION: Two AMI patients contributed to the data synthesis by giving simple feedback about the final themes.


Assuntos
COVID-19 , Pandemias , Humanos , Pesquisa Qualitativa , Pessoal de Saúde
3.
J Nurs Manag ; 30(2): 511-520, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34890482

RESUMO

AIM: The aim of this work is to investigate nurses' perceptions of barriers constraining the implementation of the Internet Plus Nursing Service program. BACKGROUND: The Internet Plus Nursing Service programme helps meet the demands of an ageing population, people with chronic diseases, the disabled, and home convalescents, and affirms the value of nurses. However, this programme has failed to elicit nurses' active participation, and there is limited knowledge regarding nurses' perceptions of the barriers to the programme's implementation. METHODS: A qualitative study was conducted. Thematic analysis of the data was performed. RESULTS: The analysis yielded three main themes: a sense of insecurity, role conflict, and a lack of support. CONCLUSION: This study explores nurses' perspectives on the factors impeding the implementation of the programme, which are identified as being insufficient protection and support on nurses at personal, sociocultural, infrastructural, and organizationallevels. IMPLICATIONS FOR NURSING MANAGEMENT: The study results will guide the department of nursing management to foster supportive work and social environment for nurses, which will decrease their feeling of insecurity and role conflicts and provides them enough infrastructural and organizational supports through proposing emergency code system and improving training system and team collaboration.


Assuntos
Enfermeiras e Enfermeiros , Serviços de Enfermagem , Humanos , Internet , Pesquisa Qualitativa
4.
Phys Chem Chem Phys ; 19(38): 26072-26084, 2017 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-28926043

RESUMO

To date, there have been only a few studies focusing on the assignment of X-ray diffraction (XRD) patterns in graphitic carbon nitrides (g-C3N4) and contradictory determination for a broad peak around 12°-14° has been perplexing. In this study, assignments are carried out both theoretically and experimentally. The cell parameters for g-C3N4 are determined as a = b = 8.1 Å, c = 6.5 Å, α = ß = 90°, and γ = 120°. Qualitative and semi-quantitative methods such as fast Fourier transform and residual after 1st and 2nd derivatives are used to confirm and search the hidden peaks. Discrete Fourier transform is applied for the extraction of peak profiles and separation of overlapping peaks. In the broad peak around 12°-14° (with Cu Kα as referring source), two peaks are selected and determined as (100) and (001), which is fairly consistent with the (200) diffraction peak and (002) diffraction peak obtained by 2nd derivative method, respectively. In addition, g-C3N4 nanorods, MOF-doped g-C3N4 nanorods, and oxidized bulk g-C3N4 are successively investigated to present the 7.0 Å d-spacing of (100), hexagonal system of bulk g-C3N4, defect (1/2 0 0) structure with 14.0 Å d-spacing, and ABA stacking sequence. The structural transition in the oxidation of bulk g-C3N4 is presented by XRD to show accordance with the interpretation. Specific phenomena reported in other studies are also reinterpreted successfully, such as the appearance of peak at ∼12.4°.

5.
Biochem Biophys Res Commun ; 446(4): 1261-7, 2014 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-24690174

RESUMO

Previous studies from this laboratory indicated that microRNA-21 (miR-21) contributes to chemoresistance of glioblastoma multiforme (GBM) cells to teniposide, a type II topoisomerase inhibitor. We also showed that LRRFIP1 is a target of miR-21. In this study, we found that higher baseline LRRFIP1 expression in human GBM tissue (n=60) is associated with better prognosis upon later treatment with teniposide. Experiments in cultured U373MG cells showed enhanced toxicity of teniposide against U373MG cells transfected with a vector that resulted in LRRFIP1 overexpression (vs. cells transfected with control vector). Experiments in nude mice demonstrated better response of LRRFIP1 overexpressing xenografts to teniposide. These findings indicate that high baseline LRRFIP1 expression in GBM is associated with better response to teniposide, and encourage exploring LRRFIP1 as a target for GBM treatment.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Proteínas de Ligação a RNA/genética , Teniposídeo/uso terapêutico , Inibidores da Topoisomerase II/uso terapêutico , Regulação para Cima , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glioblastoma/diagnóstico , Glioblastoma/genética , Humanos , Camundongos , Camundongos Nus , MicroRNAs/genética , Prognóstico , Transfecção
6.
EMBO J ; 28(18): 2719-32, 2009 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-19696742

RESUMO

We here report that miR-17-92 cluster is a novel target for p53-mediated transcriptional repression under hypoxia. We found the expression levels of miR-17-92 cluster were reduced in hypoxia-treated cells containing wild-type p53, but were unchanged in hypoxia-treated p53-deficient cells. The repression of miR-17-92 cluster under hypoxia is independent of c-Myc. Luciferase reporter assays mapped the region responding to p53-mediated repression to a p53-binding site in the proximal region of the miR-17-92 promoter. Chromatin immunoprecipitation (ChIP), Re-ChIP and gel retardation assays revealed that the binding sites for p53- and the TATA-binding protein (TBP) overlap within the miR-17-92 promoter; these proteins were found to compete for binding. Finally, we show that pri-miR-17-92 expression correlated well with p53 status in colorectal carcinomas. Over-express miR-17-92 cluster markedly inhibits hypoxia-induced apoptosis, whereas blocked miR-17-5p and miR-20a sensitize the cells to hypoxia-induced apoptosis. These data indicated that p53-mediated repression of miR-17-92 expression likely has an important function in hypoxia-induced apoptosis, and thus further our understanding of the tumour suppressive function of p53.


Assuntos
Apoptose , MicroRNAs/genética , Família Multigênica , Proteína Supressora de Tumor p53/genética , Sítios de Ligação , Células CACO-2 , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Humanos , Hipóxia , Cinética , Luciferases/metabolismo , Modelos Biológicos , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Zhonghua Nei Ke Za Zhi ; 52(11): 945-50, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24439189

RESUMO

OBJECTIVE: To set up a prediction rule for the pro-operative differential diagnosis of thyroid nodules and evaluate its clinical value. METHODS: All patients of thyroid nodules underwent thyroid operations in Changzheng hospital from June, 1997 to July, 2012 were included in this study. They were randomly divided into the derivation cohort (2/3) and the validation cohort (1/3). A prediction rule was developed based on the logistic regression model and the scoring system was established in accordance with assigning of the value of each variable ß in the model. The prediction consistency, discriminatory power and diagnostic accuracy were conducted to evaluate the clinical value of the scoring system. RESULTS: A total of 13 980 patients were enrolled in the study with 9195 in the derivation cohort and 4785 in the validation cohort. The prediction rule consisted of 18 variables, which were gender, clinical manifestations including fever, neck sore, neck mass, palpitation and sweating, serum level of thyroid stimulating hormone (TSH) , free triiodothyronine (FT3) , thyroid peroxidase antibody (TPOAb) , thyroglobulin antibody (TgAb) , thyroglobulin (Tg) , calcitonin and carcinoembryonic antigen (CEA) , ultrasonography features including nodules number, location, size, boundaries and ethological patterns and the presence and patterns of lymph nodes. The model showed good calibration consistency (P = 0.437) and discrimination power (area under the receiver operating characteristic curve was 0.928) in the derivation cohort. The sensitivity, specificity, accuracy, positive predictive value, negative predictive value, positive likelihood ratio and negative likelihood ratio of the model were 89.3%, 81.5%, 83.2%, 56.8%, 96.6%, 4.83 and 0.13, respectively. CONCLUSION: The prediction rule and its scoring system established in the study are efficacious for the calibration and discrimination of thyroid nodules in Chinese population, which could be a useful tool for the pro-operative risk stratification.


Assuntos
Nódulo da Glândula Tireoide/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
8.
ACS Appl Mater Interfaces ; 15(3): 4835-4844, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36642925

RESUMO

Three-dimensional (3D) woven Ag nanowire (AgNW) grids have great potential for enhancing the mechanical stabilities, conductivity, and transmittance of flexible transparent electrodes (FTEs). However, it is a great challenge to control the formation of 3D woven AgNW grids on various substrates, especially the poly(dimethylsiloxane) (PDMS) substrate. This work presents a microtransfer-printing method for preparing a high-wettability poly(dimethylsiloxane) (PDMS) substrate to control the formation of 3D woven AgNW grids. The as-prepared PDMS substrate shows a high wettability performance. The surface structures of the PDMS substrate can control the sharp shrinkage of the ink membrane to give rise to a uniform liquid membrane evaporation behavior, which is the key factor for preparing a uniform 3D woven nanowire network. A thin uniform 3D woven AgNW network with a low sheet resistance of 24.3 Ω/□ and high transmittance of 92% was coated on the PDMS substrate. The networks directly coated the surface of the replicated PDMS, which simplified the peeling process and protected the networks from peeling strain and mechanical deformations. Moreover, the increment of resistance retained a small value (∼5%) when bending cycles reached 9,000. An alternating current electroluminescent (ACEL) device was prepared, and the uniform electroluminescence implies that a defect-free electrode has been fabricated. These results indicate that the as-prepared FTEs have excellent mechanical performance and great potential for flexible optoelectronic applications.

9.
Opt Lett ; 36(9): 1713-5, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21540978

RESUMO

In this paper, the optical properties of the silicon nano-cone-hole (NCH) structure array are studied. The ultimate efficiency of the optimized NCH array is enhanced by 23.11% compared to an optimized nanohole array of the same thickness. The absorptance enhancement of the NCH arrays is attributed to its lowered reflectance, more supported resonant modes, and enhanced mode interaction. The angular dependence of ultimate efficiency is also investigated.

10.
Opt Lett ; 36(10): 1884-6, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21593923

RESUMO

In this Letter, the optical properties of randomly positioned silicon nanowire arrays are studied. The result shows that position randomization with a filling ratio larger than 36% renders better absorptance over a broadband ranging from 300 to 1130 nm compared to regular structures. The ultimate efficiency of a 48% filling ratio position randomized nanowire structure is 13.4% higher compared to the optimized regularly arranged nanowire structure with the same thickness. The absorptance enhancement of random structures is attributed to lowered reflectance, more supported resonant modes, and broadening of existing resonance.

11.
Zhonghua Yu Fang Yi Xue Za Zhi ; 45(11): 1026-30, 2011 Nov.
Artigo em Zh | MEDLINE | ID: mdl-22336281

RESUMO

OBJECTIVE: The present work aims to investigate the effects of subacute exposure to diesel exhaust particles (DEP) on reproductive function in female mice. METHODS: A total of 168 ICR (Institute of Cancer Research) mice were randomly divided into four groups by numeration table method, including the low (B), middle (C), high (D) dose DEP exposure groups and the control group (A). Each group consisted of 42 mice. Mice were inoculated with 30 µl DEP suspension at 0.8 (B), 3.0 (C), 12.0 (D) µg/µl, respectively, or the same volume of phosphate-buffered saline (A) on pharynx posterior wall per triduum for 4 times. The body weight and ovary weight were tested and ovary weight/body weight ratios were calculated. Rates of survival, germinal vesicle breakdown, extrusion of the first polar body, in-vitro fertilization and quantity of mitochondrial DNA for the oocytes were investigated. Ultrastructural changes of the oocytes were observed. RESULTS: The ovary weight/body weight ratios were (15.4 ± 7.3) × 10(-5), (14.1 ± 6.8) × 10(-5), (8.2 ± 0.7) × 10(-5) and (7.2 ± 2.5) × 10(-5) in groups A, B, C and D (F = 3.841, P < 0.05). In groups A, B, C and D at 48 h post-insemination, rates of oocyte survival were 64.3%, 56.8%, 39.5% and 32.9% (χ(2) = 21.575, P < 0.05), rates of extrusion of the first polar body were 75.5%, 65.3%, 37.0% and 27.1% (χ(2) = 52.772, P < 0.05), rates of 2-cell embryos were 27.9%, 39.1%, 17.6% and 12.5% (χ(2) = 20.148, P < 0.05), and rates of embryos over 2 cells were 45.3%, 32.2%, 12.5% and 13.9% (χ(2) = 32.135, P < 0.05), respectively, and were significantly lower in groups C and D compared with group A (P < 0.05). Logarithmic values of mitochondrial DNA copy numbers were 6.54 ± 0.13, 6.48 ± 0.09, 5.57 ± 0.15 and 5.41 ± 0.07 in groups A, B, C and D, respectively, and were significantly lower in groups C and D compared with group A or B (F = 89.241, P < 0.05). A number of mitochondria of the oocytes exhibited tremendous tumescence and vacuolization in groups C and D, which was contrast to a roughly normal appearance in groups A and B. CONCLUSIONS: DEP is noxious to murine female reproduction. Subacute exposure to DEP injures the ovary and oocyte resulting in compromised ovarian function and fertilizability of the oocyte.


Assuntos
Oócitos/efeitos dos fármacos , Ovário/efeitos dos fármacos , Emissões de Veículos/toxicidade , Animais , Feminino , Camundongos , Camundongos Endogâmicos ICR , Ovário/citologia
12.
Med Sci Monit ; 16(10): HY27-30, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20885358

RESUMO

ABCG2, which encodes an ATP-binding cassette transporter protein, is associated with the phenotype of cancer stem cells and is used to define the pluripotential side population cells by flow cytometry and slide-cytometry. MicroRNAs control a wide array of biological processes (e.g., cell differentiation, proliferation and apoptosis) whose dysregulation is a hallmark of cancer. MicroRNA-328 (miR-328) is underexpressed in many cancers including glioblastoma multiforme and contributes to tumor resistance to chemotherapy. ABCG2 is associated with multi-drug resistance and is also highly expressed in glioblastoma. Some preliminary studies have shown that ABCG2 is the target gene for miRNA-328. Thus, we hypothesize that modulating ABCG2 expression by targeting miRNA-328 in glioblastoma cancer stem cells could represent a promising strategy for therapeutic manipulation to increase the efficacy of chemotherapeutic agents for glioblastoma, a highly lethal type of cancer.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Neoplasias Encefálicas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/genética , MicroRNAs/genética , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/biossíntese , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Neoplasias Encefálicas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Expressão Gênica , Glioblastoma/metabolismo , Humanos , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia
13.
Eur Radiol ; 19(2): 517-20, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19153746

RESUMO

Epithelioid hemangioendothelioma is a rare, low-grade malignant hemangioendothelioma first reported in 1982. The disease is more likely to occur between 20 and 30 years with a 2:1 male-to-female ratio. Epithelioid hemangioendothelioma may occur in multiple organs and tissues, but it rarely involves the skeleton. We present a case in a thoracic vertebra.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Hemangioendotelioma Epitelioide/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Dor nas Costas , Neoplasias Ósseas/patologia , Meios de Contraste/farmacologia , Feminino , Gadolínio DTPA/farmacologia , Hemangioendotelioma Epitelioide/patologia , Humanos , Vértebras Torácicas/patologia , Tomografia Computadorizada por Raios X/métodos
14.
Zhong Yao Cai ; 32(7): 1125-8, 2009 Jul.
Artigo em Zh | MEDLINE | ID: mdl-19873741

RESUMO

OBJECTIVE: To determine the parameters of refining process of Flos Chrysanthemi extract with macroporous adsorption resin. METHODS: According to the chlorogenic acid and total flavonoids, to investigate the kind of macoroporous resin, the maximum quantity of physic liquor, and the type and quantity of elution solvent. Then combining with the retention rate of luteolin, to verify the parameters of the process. RESULTS: The maximum adsorption quantity of chlorogenic acid was 10.8 mg/g dry resin, and the elution solvent was 5-fold column volume of 80% alcohol; the purity of total flavonoids, chlorogenic acid and luteolin were 589.2%, 605.4%, 650.1%, respectively. CONCLUSION: The resin F can enrich the active components of Flos Chrysanthemi effectively.


Assuntos
Chrysanthemum/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Flores/química , Resinas Sintéticas/química , Tecnologia Farmacêutica/métodos , Adsorção , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Etanol/química , Flavonoides/análise , Luteolina/análise , Plantas Medicinais/química
15.
Nanoscale Res Lett ; 14(1): 360, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792627

RESUMO

Hybrid heterojunctions based on two-dimensional (2D) and conventional three-dimensional (3D) materials provide a promising way toward nanoelectronic devices with engineered features. In this work, we investigated the band alignment of a mixed-dimensional heterojunction composed of transferred MoS2 on ß-Ga2O3([Formula: see text]01) with and without nitridation. The conduction and valence band offsets for unnitrided 2D-MoS2/3D-ß-Ga2O3 heterojunction were determined to be respectively 0.43 ± 0.1 and 2.87 ± 0.1 eV. For the nitrided heterojunction, the conduction and valence band offsets were deduced to 0.68 ± 0.1 and 2.62 ± 0.1 eV, respectively. The modified band alignment could result from the dipole formed by charge transfer across the heterojunction interface. The effect of nitridation on the band alignments between group III oxides and transition metal dichalcogenides will supply feasible technical routes for designing their heterojunction-based electronic and optoelectronic devices.

16.
Nanoscale Res Lett ; 13(1): 246, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30136254

RESUMO

Ultra-wide bandgap beta-gallium oxide (ß-Ga2O3) has been attracting considerable attention as a promising semiconductor material for next-generation power electronics. It possesses excellent material properties such as a wide bandgap of 4.6-4.9 eV, a high breakdown electric field of 8 MV/cm, and exceptional Baliga's figure of merit (BFOM), along with superior chemical and thermal stability. These features suggest its great potential for future applications in power and optoelectronic devices. However, the critical issue of contacts between metal and Ga2O3 limits the performance of ß-Ga2O3 devices. In this work, we have reviewed the advances on contacts of ß-Ga2O3 MOSFETs. For improving contact properties, four main approaches are summarized and analyzed in details, including pre-treatment, post-treatment, multilayer metal electrode, and introducing an interlayer. By comparison, the latter two methods are being studied intensively and more favorable than the pre-treatment which would inevitably generate uncontrollable damages. Finally, conclusions and future perspectives for improving Ohmic contacts further are presented.

17.
J Gastrointest Surg ; 22(5): 872-883, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29313290

RESUMO

BACKGROUND: Chronic HBV plays an important role in hepatocellular carcinoma pathogenesis. Previously, most studies have been focusing on HBV DNA levels before the primary curative hepatectomy. However, the association of virus level before repeat hepatectomy with the degrees of inflammation and fibrosis on histopathology and prognosis has not been surveyed. METHODS: From January 2002 to December 2009, all patients who were seropositive for hepatitis B surface antigen (HBsAg) were enrolled and assigned into four groups based on their HBV DNA levels before the primary and repeat hepatectomies. The cancer prognoses of these four groups of patients after the first and second operations were assessed and compared. The disease-free survival and overall survival were estimated by the Kaplan-Meier method. Univariate and multivariate analyses were performed to identify risk factors for the primary and repeat hepatectomies. RESULTS: For the 385 patients in this study, a low level of serum HBV DNA before repeat hepatectomy, but not primary hepatectomy, was significantly associated with improvement in prognosis, in terms of tumor recurrence, liver fibrosis, and liver-related mortality. CONCLUSION: The levels of HBV DNA before hepatectomies were crucial prognostic risk factors of HBV-related hepatocellular carcinoma patients. Surveillance of serum HBV DNA levels at multiple time points, rather than at a single time point, and antiviral therapy to suppress the virus to a low level had beneficial effects for these patients.


Assuntos
Carcinoma Hepatocelular/cirurgia , DNA Viral/sangue , Vírus da Hepatite B , Hepatite B Crônica/sangue , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/sangue , Carga Viral , Carcinoma Hepatocelular/virologia , Intervalo Livre de Doença , Hepatectomia , Hepatite B Crônica/complicações , Humanos , Estimativa de Kaplan-Meier , Cirrose Hepática/virologia , Neoplasias Hepáticas/virologia , Recidiva Local de Neoplasia/virologia , Período Pré-Operatório , Prognóstico , Reoperação , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
18.
Cell Stem Cell ; 23(1): 114-122.e3, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29937200

RESUMO

Chronic liver injury can cause cirrhosis and impaired liver regeneration, impairing organ function. Adult livers can regenerate in response to parenchymal insults, and multiple cellular sources have been reported to contribute to this response. In this study, we modeled human chronic liver injuries, in which such responses are blunted, without genetic manipulations, and assessed potential contributions of non-parenchymal cells (NPCs) to hepatocyte regeneration. We show that NPC-derived hepatocytes replenish a large fraction of the liver parenchyma following severe injuries induced by long-term thioacetamide (TAA) or 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) treatment. Through lineage tracing of biliary epithelial cells (BECs), we show that BECs are a source of new hepatocytes and gain an Hnf4α+CK19+ bi-phenotypic state in periportal regions and fibrotic septa. Bi-phenotypic cells were also detected in cirrhotic human livers. Together, these data provide further support for hepatocyte regeneration from BECs without genetic interventions and show their cellular plasticity during severe liver injury.


Assuntos
Células Epiteliais/patologia , Hepatócitos/patologia , Cirrose Hepática/patologia , Animais , Doença Crônica , Humanos , Cirrose Hepática/induzido quimicamente , Camundongos , Camundongos Endogâmicos , Tioacetamida
19.
Nanoscale Res Lett ; 12(1): 499, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28815429

RESUMO

The surface polarization of Ga-face gallium nitride (GaN) (2 nm)/AlGaN (22 nm)/GaN channel (150 nm)/buffer/Si with Al2O3 capping layer is investigated by angle-resolved X-ray photoelectron spectroscopy (ARXPS). It is found that the energy band varies from upward bending to downward bending in the interface region, which is believed to be corresponding to the polarization variation. An interfacial layer is formed between top GaN and Al2O3 due to the occurrence of Ga-N bond break and Ga-O bond forming during Al2O3 deposition via the atomic layer deposition (ALD). This interfacial layer is believed to eliminate the GaN polarization, thus reducing the polarization-induced negative charges. Furthermore, this interfacial layer plays a key role for the introduction of the positive charges which lead the energy band downward. Finally, a N2 annealing at 400 °C is observed to enhance the interfacial layer growth thus increasing the density of positive charges.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA