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1.
Nanotechnology ; 35(1)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37783207

RESUMO

In order to reduce the etching effect of the catalysts to carbon fibers caused by high temperature during the chemical vapor deposition (CVD) process, four multi-element catalysts, Fe-Co, Fe-Ni, Co-Ni and Fe-Co-Ni, were used to realize the low temperature growth of carbon nanotubes (CNTs) on carbon fibers at 350 °C-400 °C. The results show that the growth state of CNTs has a great relationship with the type of catalysts. The catalytic efficiency of Fe-Co catalysts is low, but the graphitization degree of CNTs is relatively high. The Fe-Co-Ni catalysts has high catalytic efficiency but low graphitization degree of CNTs. The tensile strength of carbon fiber/CNTs reinforcements prepared by Fe-Ni catalysts at 400 °C is the highest, reaching 3.99 GPa, which is 11.14% higher than that of desized fiber. The melt drop phenomenon of the catalysts was found by TEM, indicating the formation of the liquid phase catalysts during the growth of CNTs. This phenomenon can change the diffusion mode of carbon atoms in the catalyst and significantly reduce the growth activation energy of CNTs, so that CNTs can grow at lower temperatures. Based on the detailed analysis of the CVD process, a low temperature growth model of CNTs on carbon fibers was proposed.

2.
Langmuir ; 38(7): 2392-2400, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35148119

RESUMO

Two kinds of carbon nanoproducts with different microstructures, namely, carbon nanotubes (CNTs) and carbon nanofibers (CNFs), were grown on the surface of carbon fibers (CFs) by chemical vapor deposition (CVD) at low temperatures to improve the interface bonding between fibers and resins. The short-beam method and the micro-debonding method were used to test the interlaminar shear strength (ILSS) and interfacial shear strength (IFSS) of the composites. The results showed that the contribution of CNTs to the improvement of interfacial properties was better than that of CNFs. Specifically, the ILSS and IFSS of the CF-CNFs/epoxy composites increased by 18.59 and 24.39%, respectively, while the ILSS and IFSS of the CF-CNTs/epoxy composites increased by 26.97 and 47.79%, respectively. Compared with CNFs, the high degree of graphitization of CNTs and the π-interactions with the resin can better induce the formation of an interphase between the fiber and the resin, which suppressed the initiation of cracks and extended the propagation path of the cracks in the composites.

3.
Stroke ; 52(1): 213-222, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33349014

RESUMO

BACKGROUND AND PURPOSE: Aneurysmal wall enhancement (AWE) on vessel wall magnetic resonance imaging (VW-MRI) has been described as a new imaging biomarker of unstable unruptured intracranial aneurysms (UIAs). Previous studies of symptomatic UIAs are limited due to small sample sizes and lack of AWE quantification. Our study aims to investigate whether qualitative and quantitative assessment of AWE can differentiate symptomatic and asymptomatic UIAs. METHODS: Consecutive patients with UIAs were prospectively recruited for vessel wall magnetic resonance imaging at 3T from October 2014 to October 2019. UIAs were categorized as symptomatic if presenting with sentinel headache or oculomotor nerve palsy directly related to the aneurysm. Evaluation of wall enhancement included enhancement pattern (0=none, 1=focal, and 2=circumferential) and quantitative wall enhancement index (WEI). Univariate and multivariate analyses were used to identify the parameters associated with symptoms. RESULTS: Two hundred sixty-seven patients with 341 UIAs (93 symptomatic and 248 asymptomatic) were included in this study. Symptomatic UIAs more frequently showed circumferential AWE than asymptomatic UIAs (66.7% versus 17.3%, P<0.001), as well as higher WEI (median [interquartile range], 1.3 [1.0-1.9] versus 0.3 [0.1-0.9], P<0.001). In multivariate analysis, both AWE pattern and WEI were independent factors associated with symptoms (odds ratio=2.03 across AWE patterns [95% CI, 1.21-3.39], P=0.01; odds ratio=3.32 for WEI [95% CI, 1.51-7.26], P=0.003). The combination of AWE pattern and WEI had an area under the curve of 0.91 to identify symptomatic UIAs, with a sensitivity of 95.7% and a specificity of 73.4%. CONCLUSIONS: In a large cohort of UIAs with vessel wall magnetic resonance imaging, both AWE pattern and WEI were independently associated with aneurysm-related symptoms. The qualitative and quantitative features of AWE can potentially be used to identify unstable intracranial aneurysms.


Assuntos
Vasos Sanguíneos/diagnóstico por imagem , Aneurisma Intracraniano/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Aneurisma Roto/diagnóstico por imagem , Angiografia Digital , Área Sob a Curva , Angiografia Cerebral , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Aneurisma Intracraniano/terapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Sensibilidade e Especificidade
4.
BMC Cancer ; 21(1): 858, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315402

RESUMO

BACKGROUND: Bladder cancer (BC) is a common malignancy neoplasm diagnosed in advanced stages in most cases. It is crucial to screen ideal biomarkers and construct a more accurate prognostic model than conventional clinical parameters. The aim of this research was to develop and validate an mRNA-based signature for predicting the prognosis of patients with bladder cancer. METHODS: The RNA-seq data was downloaded from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Differentially expressed genes (DEGs) were screened in three datasets, and prognostic genes were identified from the training set of TCGA dataset. The common genes between DEGs and prognostic genes were narrowed down to six genes via Least Absolute Shrinkage and Selection Operator (LASSO) regression, and stepwise multivariate Cox regression. Then the gene-based risk score was calculated via Cox coefficient. Time-dependent receiver operating characteristic (ROC) and Kaplan-Meier (KM) survival analysis were used to assess the prognostic power of risk score. Multivariate Cox regression analysis was applied to construct a nomogram. Decision curve analysis (DCA), calibration curves, and time-dependent ROC were performed to assess the nomogram. Finally, functional enrichment of candidate genes was conducted to explore the potential biological pathways of candidate genes. RESULTS: SORBS2, GPC2, SETBP1, FGF11, APOL1, and H1-2 were screened to be correlated with the prognosis of BC patients. A nomogram was constructed based on the risk score, pathological stage, and age. Then, the calibration plots for the 1-, 3-, 5-year OS were predicted well in entire TCGA-BLCA patients. Decision curve analysis (DCA) indicated that the clinical value of the nomogram was higher than the stage model and TNM model in predicting overall survival analysis. The time-dependent ROC curves indicated that the nomogram had higher predictive accuracy than the stage model and risk score model. The AUC of nomogram time-dependent ROC was 0.763, 0.805, and 0.806 for 1-year, 3-year, and 5-year, respectively. Functional enrichment analysis of candidate genes suggested several pathways and mechanisms related to cancer. CONCLUSIONS: In this research, we developed an mRNA-based signature that incorporated clinical prognostic parameters to predict BC patient prognosis well, which may provide a novel prognosis assessment tool for clinical practice and explore several potential novel biomarkers related to the prognosis of patients with BC.


Assuntos
Biomarcadores Tumorais , Transcriptoma , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/mortalidade , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Mutação , Estadiamento de Neoplasias , Nomogramas , Prognóstico , RNA Mensageiro , Curva ROC , Reprodutibilidade dos Testes , Neoplasias da Bexiga Urinária/patologia
5.
Nanotechnology ; 32(28)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33823501

RESUMO

Carbon nanotubes (CNTs) were continuously grown on the surface of the moving carbon fiber by chemical vapor deposition method using a custom-designed production line to prepare composite reinforcements on a large-scale. The systematic study of different parameters affecting the CNT growth revealed simple growth kinetics, which helps to control the surface morphology and structural quality of CNTs. Since hydrogen maintains the activity of the catalyst, it promotes the growth of CNTs in a continuous process. The increase of acetylene partial pressure promotes the accumulation of amorphous or graphite carbon on the catalyst surface, resulting in the decrease of CNT growth rate when acetylene concentration reaches 40%. The growth temperature significantly affects the CNT diameter and structural quality. As the temperature increases, the crystallinity of the tube wall increases obviously, and the CNT diameter increases due to the aggregate growth of the catalyst particles. According to the Arrhenius formula, the apparent activation energy is observed to be 0.67 eV, which proves that both bulk diffusion and surface diffusion exist when activated carbon passes through the catalyst to form CNTs.

6.
Sensors (Basel) ; 20(12)2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575469

RESUMO

In time-of-arrival (TOA)-based source localization, accurate positioning can be achieved only when the correct signal propagation time between the source and the sensors is obtained. In practice, a clock error usually exists between the nodes causing the source and sensors to often be in an asynchronous state. This leads to the asynchronous source localization problem which is then formulated to a least square problem with nonconvex and nonsmooth objective function. The state-of-the-art algorithms need to relax the original problem to convex programming, such as semidefinite programming (SDP), which results in performance loss. In this paper, unlike the existing approaches, we propose a proximal alternating minimization positioning (PAMP) method, which minimizes the original function without relaxation. Utilizing the biconvex property of original asynchronous problem, the method divides it into two subproblems: the clock offset subproblem and the synchronous source localization subproblem. For the former we derive a global solution, whereas the later is solved by a proposed efficient subgradient algorithm extended from the simulated annealing-based Barzilai-Borwein algorithm. The proposed method obtains preferable localization performance with lower computational complexity. The convergence of our method in Lyapunov framework is also established. Simulation results demonstrate that the performance of PAMP method can be close to the optimality benchmark of Cramér-Rao Lower Bound.

7.
Small ; 15(19): e1900484, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30941902

RESUMO

All-inorganic semiconductor perovskite quantum dots (QDs) with outstanding optoelectronic properties have already been extensively investigated and implemented in various applications. However, great challenges exist for the fabrication of nanodevices including toxicity, fast anion-exchange reactions, and unsatisfactory stability. Here, the ultrathin, core-shell structured SiO2 coated Mn2+ doped CsPbX3 (X = Br, Cl) QDs are prepared via one facile reverse microemulsion method at room temperature. By incorporation of a multibranched capping ligand of trioctylphosphine oxide, it is found that the breakage of the CsPbMnX3 core QDs contributed from the hydrolysis of silane could be effectively blocked. The thickness of silica shell can be well-controlled within 2 nm, which gives the CsPbMnX3 @SiO2 QDs a high quantum yield of 50.5% and improves thermostability and water resistance. Moreover, the mixture of CsPbBr3 QDs with green emission and CsPbMnX3 @SiO2 QDs with yellow emission presents no ion exchange effect and provides white light emission. As a result, a white light-emitting diode (LED) is successfully prepared by the combination of a blue on-chip LED device and the above perovskite mixture. The as-prepared white LED displays a high luminous efficiency of 68.4 lm W-1 and a high color-rendering index of Ra = 91, demonstrating their broad future applications in solid-state lighting fields.

8.
Eur Radiol ; 29(2): 689-698, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30019140

RESUMO

OBJECTIVES: The study aimed to determine which hemodynamic parameters independently characterize anterior communicating artery (AcomA) aneurysm formation and explore the threshold of wall shear stress (WSS) of the parent artery to better illustrate the correlation between the magnitude of WSS and AcomA aneurysm formation. METHODS: Eighty-one patients with AcomA aneurysms and 118 patients without intracranial aneurysms (control population), as confirmed by digital subtraction angiography (DSA) from January 2014 to May 2017, were included in this cross-sectional study. Three-dimensional-DSA was performed to evaluate the morphologic characteristics of AcomA aneurysms. Local hemodynamic parameters were obtained using transcranial color-coded duplex (TCCD). Multivariate logistic regression and a two-piecewise linear regression model were used to determine which hemodynamic parameters are independent predictors of AcomA aneurysm formation and identify the threshold effect of WSS of the parent artery with respect to AcomA aneurysm formation. RESULTS: Univariate analyses showed that the WSS (p < 0.0001), angle between the A1 and A2 segments of the anterior cerebral artery (ACA) (p < 0.001), hypertension (grade II) (p = 0.007), fasting blood glucose (FBG; > 6.0 mmol/L) (p = 0.005), and dominant A1 (p < 0.001) were the significant parameters. Multivariate analyses showed a significant association between WSS of the parent artery and AcomA aneurysm formation (p = 0.0001). WSS of the parent artery (7.8-12.3 dyne/cm2) had a significant association between WSS and aneurysm formation (HR 2.0, 95% CI 1.3-2.8, p < 0.001). CONCLUSIONS: WSS ranging between 7.8 and 12.3 dyne/cm2 independently characterizes AcomA aneurysm formation. With each additional unit of WSS, there was a one-fold increase in the risk of AcomA aneurysm formation. KEY POINTS: • Multivariate analyses and a two-piecewise linear regression model were used to evaluate the risk factors for AcomA aneurysm formation and the threshold effect of WSS on AcomA aneurysm formation. • WSS ranging between 7.8 and 12.3 dyne/cm 2 was shown to be a reliable hemodynamic parameter in the formation of AcomA aneurysms. The probability of AcomA aneurysm formation increased one-fold for each additional unit of WSS. • An ultrasound-based TCCD technique is a simple and accessible noninvasive method for detecting WSS in vivo; thus, it can be applied as a screening tool for evaluating the probability of aneurysm formation in primary care facilities and community hospitals because of the relatively low resource intensity.


Assuntos
Artéria Cerebral Anterior/fisiopatologia , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Adulto , Idoso , Angiografia Digital , Artéria Cerebral Anterior/diagnóstico por imagem , Artéria Cerebral Anterior/patologia , Estudos de Casos e Controles , Angiografia Cerebral/métodos , Circulação Cerebrovascular/fisiologia , Estudos Transversais , Feminino , Hemodinâmica/fisiologia , Humanos , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade , Estresse Mecânico , Ultrassonografia Doppler Transcraniana/métodos
9.
Nanotechnology ; 29(39): 395602, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-29972379

RESUMO

An effective approach has been developed for the catalytic decomposition of acetylene (C2H2) by chemical vapor deposition (CVD), to achieve homogeneous growth of carbon nanotubes (CNTs) on the surfaces of carbon fibers. The morphology of CNTs grown on carbon fiber surfaces was observed by a scanning electron microscope and high-resolution transmission electron microscope, which revealed the uniform coverage of CNTs on the carbon fiber surfaces. The single fiber tensile test demonstrated that the tensile strength of carbon fibers could be increased by more than 12% with the catalytic growth of CNTs on their surface. The reparation of the damage caused during the formation of catalyst nanoparticles, and the cross-link of neighboring graphite crystallites induced by CNTs all occurred during the CVD process, which were considered to be the main reasons for improvement. The growth mechanism model of CNTs formation was established based on the thermodynamics principle and the interface microstructure of CNT-grown carbon fiber, illuminating the detailed mechanism for the growth of CNTs and the change of the shape of catalyst particles.

10.
J Chem Inf Model ; 56(10): 1979-1994, 2016 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-27529495

RESUMO

The discovery of unique substrates is important for developing potential applications of enzymes. However, the experimental procedures for substrate identification are laborious, time-consuming, and expensive. Although in silico structure-based approaches show great promise, recent extensive studies have shown that these approaches remain a formidable challenge for current biocomputational methodologies. Here we present an open-source, extensible, and flexible software platform for predicting enzyme substrates called THEMIS, which performs in silico virtual screening for potential catalytic targets of an enzyme on the basis of the enzyme's catalysis mechanism. On the basis of a generalized transition state theory of enzyme catalysis, we introduce a modified docking procedure called "mechanism-based restricted docking" (MBRD) for novel substrate recognition from molecular docking. Comprising a series of utilities written in C/Python, THEMIS automatically executes parallel-computing MBRD tasks and evaluates the results with various molecular mechanics (MM) criteria such as energy, distance, angle, and dihedral angle to help identify desired substrates. Exhaustive sampling and statistical measures were used to improve the robustness and reproducibility of the method. We used Candida antarctica lipase B (CALB) as a test system to demonstrate the effectiveness of our computational prediction of (non)substrates. A novel MM score function for CALB substrate identification derived from the near-attack conformation was used to evaluate the possibility of chemical transformation. A highly positive rate of 93.4% was achieved from a CALB substrate library with 61 known substrates and 35 nonsubstrates, and the screening rate has reached 103 compounds/day (96 CPU cores, 100 samples/compound). The performance shows that the present method is perhaps the first reported scheme to meet the requirement for practical applicability to enzyme studies. An additional study was performed to validate the universality of our method. In this verification we employed two distinct enzymes, nitrilase Nit6803 and SDR Gox2181, where the correct rates of both enzymes exceeded 90%. The source code used will be released under the GNU General Public License (GPLv3) and will be free to download. We believe that the present method will provide new insights into enzyme research and accelerate the development of novel enzyme applications.


Assuntos
Candida/enzimologia , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Sítios de Ligação , Candida/química , Candida/metabolismo , Proteínas Fúngicas/química , Lipase/química , Simulação de Acoplamento Molecular , Software , Especificidade por Substrato
11.
Phys Chem Chem Phys ; 17(1): 557-62, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25406672

RESUMO

We report here a reliable and reproducible single-step (without post-annealing) fabrication of phase-pure p-type rhombohedral CuAlO2 (r-CuAlO2) thin films by reactive magnetron sputtering. The dependence of crystallinity and phase compositions of the films on the growth temperature was investigated, revealing that highly-crystallized r-CuAlO2 thin films could be in situ grown in a narrow temperature window of ∼940 °C. Optical and electrical property studies demonstrate that (i) the films are transparent in the visible light region, and the bandgaps of the films increased to ∼3.86 eV with the improvement of crystallinity; (ii) the conductance increased by four orders of magnitude as the film was evolved from the amorphous-like to crystalline structure. The predominant role of crystallinity in determining CuAlO2 film properties was demonstrated to be due to the heavy anisotropic characteristics of the O 2p-Cu 3d hybridized valence orbitals.

12.
Transfusion ; 54(7): 1847-50, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24527852

RESUMO

BACKGROUND: The α(1,2)-fucosyltransferase gene 1 (FUT1) and 2 (FUT2), respectively, regulate H antigen synthesis in red blood cells and body fluids. Genetic polymorphisms of FUT1 and FUT2 are ethnically and geographically specific. STUDY DESIGN AND METHODS: Healthy unrelated Tibetan blood donors (n = 200) from the Tibet Autonomous Region of China were recruited for this study. The entire FUT1 and FUT2 coding regions were amplified and sequenced. The haplotypes including novel single-nucleotide polymorphisms (SNPs) were determined by clone sequencing. RESULTS: In Tibetans, the major FUT1 allele was wild-type allele with a frequency of 97.75%. One novel FUT1 allele was defined by a novel synonymous mutation (846T>G). The two most common FUT2 alleles were functional allele Se(357) with a frequency of 32.75% and nonfunctional allele se(357,385) with a frequency of 55%. Two new FUT2 alleles were found at low frequency. They were characterized by two novel SNPs on the basis of se(357,385) : 617 T>G (V206G) and 841 G>A (G281R). CONCLUSION: Three new alleles in FUT1 and FUT2 genes were identified in the study. The allelic polymorphisms of FUT1 and FUT2 in Tibetans show a population-specific manner.


Assuntos
Doadores de Sangue , Fucosiltransferases/genética , Alelos , Sequência de Bases , Frequência do Gene , Genética Populacional , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Tibet , Galactosídeo 2-alfa-L-Fucosiltransferase
13.
J Neurooncol ; 116(3): 465-76, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24381070

RESUMO

Glioblastoma multiforme (GBM) is the most malignant glioma. In the current study, 149 astrocytoma gene expression datasets were classified by prediction analysis of microarray. Strikingly, disks large homolog 3 (DLG3), a membrane-associated guanylate kinase-family gene, had the highest score in the GBM subset. DLG3 mRNA expression is significantly down-regulated in GBM relative to normal tissue and grade II or grade III astrocytoma according to the results of real-time polymerase chain reaction, and its protein expression shows an obvious difference by immunohistochemistry. Further assays show that DLG3 over-expression induces mitotic cell cycle arrest and apoptosis, and it inhibits proliferation and migration. However, DLG3 over-expression has almost no affect on invasion. The DLG3 protein expression in human brain GBM tissue and its effects on GBM cell invasion were not expected. Our data suggest that DLG3 is down-regulated in this cancer type. To our knowledge, this is the first report to clearly demonstrate the possible involvement of DLG3 in GBM.


Assuntos
Neoplasias Encefálicas/patologia , Encéfalo/metabolismo , Regulação para Baixo/fisiologia , Glioblastoma/patologia , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Adulto , Idoso , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Encéfalo/patologia , Neoplasias Encefálicas/fisiopatologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Colecistocinina/farmacologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glioblastoma/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Fragmentos de Peptídeos/farmacologia , Estudos Retrospectivos , Fatores de Tempo , Fatores de Transcrição/genética
14.
J Cancer ; 15(9): 2627-2645, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577616

RESUMO

The incidence and mortality of gynecological tumors are progressively increasing due to factors such as obesity, viral infection, unhealthy habits, as well as social and economic pressures. Consequently, it has emerged as a significant threat to women's health. Numerous studies have revealed the remarkable metabolic activity of tumor cells in glycolysis and its ability to influence malignant biological behavior through specific mechanisms. Therefore, it is crucial for patients and gynecologists to comprehend the role of glycolytic proteins, regulatory molecules, and signaling pathways in tumorigenesis, progression, and treatment. This article aims to review the correlation between abnormal glucose metabolism and gynecologic tumors including cervical cancer (CC), endometrial carcinoma (EC), and ovarian cancer (OC). The findings from this research will provide valuable scientific insights for early screening, timely diagnosis and treatment interventions while also aiding in the prevention of recurrence among individuals with gynecological tumors.

15.
Neurosurgery ; 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38047687

RESUMO

BACKGROUND AND OBJECTIVES: Stent-assisted coiling (SAC) of acutely ruptured aneurysms has been controversial. Moreover, for aneurysms originating from small diameter vessels, the SAC presents more challenges. This study aimed to investigate the predictors of perioperative complications after SAC with Leo baby stent of acutely ruptured aneurysms. METHODS: We performed a retrospective multicenter analysis of 425 patients with acutely ruptured aneurysms treated with Leo baby. We compared clinical characteristics and outcomes among patients with perioperative complications and those without. Subgroup analysis, including thromboembolic and hemorrhagic complications, was also performed. RESULTS: Immediate postoperative angiograms showed Raymond 1 in 357 aneurysms (84.2%), 2 in 53 (12.5%), and 3 in 14 (3.3%). A total of 372 patients (87.5%) were independent (modified Rankin Scale [mRS] score 0-2) at discharge. Perioperative complications occurred in 18 cases (4.2%) harboring 13 cases (3.1%) of thromboembolic complications and 5 cases (1.2%) of hemorrhagic complications. Patients with perioperative complications had a higher rate of unfavorable outcomes at discharge (P = .018), especially with thromboembolic complications (P = .043). Multivariate analysis showed that higher preoperative mRS score (P = .004), irregular shape (P = .017), and larger aneurysms (P = .049) were independent predictors of the overall complications, whereas higher preoperative mRS score (P = .022) was an independent predictor for ischemic complications. The follow-up angiogram was available for 245 patients, and the follow-up angiograms revealed Raymond 1 in 223 aneurysms (91.0%), 2 in 19 (7.8%), and 3 in 3 (1.2%). CONCLUSION: Worse clinical condition, irregular shape, and larger aneurysms were independently associated with overall complications, whereas worse clinical condition was viewed as an independent predictor for thromboembolic complications. Attention to these factors is essential for the safe treatment and prognosis of patients with acutely ruptured aneurysms.

16.
Immunology ; 136(4): 385-96, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22486354

RESUMO

Hepatitis C virus (HCV) has chronically infected an estimated 170 million people worldwide. There are many impediments to the development of an effective vaccine for HCV infection. Dendritic cells (DC) remain the most important antigen-presenting cells for host immune responses, and are capable of either inducing productive immunity or maintaining the state of tolerance to self and non-self antigens. Researchers have recently explored the mechanisms by which DC function is regulated during HCV infection, leading to impaired antiviral T-cell responses and so to persistent viral infection. Recently, DC-based vaccines against HCV have been developed. This review summarizes the current understanding of DC function during HCV infection and explores the prospects of DC-based HCV vaccine. In particular, it describes the biology of DC, the phenotype of DC in HCV-infected patients, the effect of HCV on DC development and function, the studies on new DC-based vaccines against HCV infection, and strategies to improve the efficacy of DC-based vaccines.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/virologia , Hepacivirus/imunologia , Hepatite C/imunologia , Vacinas contra Hepatite Viral/imunologia , Animais , Hepatite C/prevenção & controle , Hepatite C/virologia , Humanos , Fígado/imunologia , Camundongos , Vacinação
17.
Dalton Trans ; 51(11): 4532-4540, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35234780

RESUMO

The development of active and cost-effective bifunctional catalysts is crucial for water dissociation through electrolysis. In this study, bifunctional catalysts with Ni nanoparticles (NPs) anchored on MoO2 nanorods have been synthesized via in situ dissolution of NiMoO4-ZIF under an inert atmosphere without using hydrogen gas. The Ni-MoO2 catalyst exhibits high electrocatalytic activity by modulating the calcination temperature. Benefitingfrom the MOF transformation and accompanying Ni particles' outward diffusion, a precisely designed interface heterostructure between Ni and MoO2 was constructed. As a result, the optimized Ni-MoO2 catalyst achieves extremely low overpotentials of only 24 mV and 275 mV at 10 mA cm-2 for the hydrogen evolution reaction and oxygen evolution reaction, respectively. Furthermore, the catalyst required a small cell voltage of 1.55 V to deliver a current density of 10 mA cm-2 and remained stable over 20 h for overall water splitting. The proposed MOF-derived heterojunction protocol provides a general approach for designing and fabricating transition metal oxide catalysts for water electrolysis.

18.
Nanoscale ; 14(8): 3112-3122, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35142322

RESUMO

Two-dimensional hexagonal boron nitride (hBN) atomic crystals are excellent charge scattering screening interlayers for advanced electronic devices. Although wafer-scale single crystalline hBN monolayer films have been demonstrated on liquid Au and solid Cu (110) and (111) vicinal surfaces, their reproducible growth still remains challenging. Here, we report the facile self-aligned stitching growth of centimeter-scale quasi-single-crystalline hBN monolayer films through synergistic chemical vapor deposition growth kinetics and liquid Cu rheological kinetics control. The sublimation temperature of the ammonia borane precursor, H2 content and melting temperature of the Cu substrate are revealed to be the dominant factors that regulate hBN nucleation, growth and alignment. The flowing liquid Cu catalytic surface promotes efficient rotation of floating triangular hBN domains and provokes uniform self-alignment upon merging at a critical high temperature of 1105 °C. Identical aligned grains are constantly observed at multiple regions, which corroborate the homogeneous in-plane orientation and uniform stitching over the whole growth area. Continuous quasi-single-crystalline hBN monolayer films are produced by seamless stitching of aligned domains with the same polarity. The quasi-single-crystalline hBN monolayers are successfully included as charge scattering and trap site screening interlayers in the hBN/SiO2 gate insulator stack to build high performance InGaZnO field-effect transistors (FETs). Full suppression of hysteresis and twofold enhancement of field-effect mobility are realized for InGaZnO FETs built with hBN as the interface dielectric. The facile growth of large quasi-single-crystalline hBN monolayers on liquid Cu paves the way for future high-performance electronics.

19.
Int J Gen Med ; 15: 325-342, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035230

RESUMO

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is a commonly occurring tumor. Through a deeper understanding of the immune regulatory mechanisms in the tumor microenvironment, immunotherapy may serve as a potential treatment for cancer patients. This study aimed at identifying the survival-related immune cells and hub genes, which could be potential targets for immunotherapy in ccRCC. METHODS: The gene expression profiles and clinical data of ccRCC patients were extracted from UCSC Xena and Gene Expression Omnibus (GEO) databases. Kaplan-Meier (KM) survival and Least Absolute Shrinkage and Selection Operator (LASSO) regression analyses were utilized to select the survival-related tumor-infiltrating immune cells. Multivariate Cox regression was utilized to develop a signature based on the tumor-infiltrating immune cells (TIICs). Based on the signature, the risk score was calculated, following which the samples were divided into high-risk and low-risk groups. Differentially expressed genes (DEGs) between the two risk groups were identified. Functional enrichment analysis was performed and cytoHubba plug-in of Cytoscape was used to identify the hub genes. Multiple datasets were utilized to validate these hub genes, including the Gene Expression Profiling Interactive Analysis (GEPIA), UALCAN, and the Human Protein Atlas (HPA), and the GEO datasets. Finally, a correlation analysis was performed to evaluate the relationship between the hub genes and TIICs. RESULTS: Four immune survival-related cells, including T cell CD4 memory-activated, T cell regulatory (Tregs), eosinophils, and mast cell resting were identified. Nine immune-specific hub genes were identified, which included APOE, CASR, CTLA4, CXCL8, EGF, F2, KNG1, MMP9, and IL6. Furthermore, these hub genes were significantly correlated with clinical traits and closely associated with some TIICs. CONCLUSION: A total of four survival-related immune cell types and nine hub genes were found to be closely associated with ccRCC. These findings may have implications for the development of novel potential immunotherapeutic targets for ccRCC.

20.
Front Mol Biosci ; 9: 1022725, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438660

RESUMO

Triple-negative breast cancer (TNBC) is a heterogeneous and invasive breast cancer (BC) subtype that is estrogen receptor-negative, progesterone receptor-negative, and human epidermal growth factor receptor 2 (Her2)-negative. So far, the treatment of TNBC is still ineffective due to the lack of well-defined molecular targets. Exosomes are nanosized extracellular vesicles composed of lipid bilayers. They originate from various types of donor cells and release a complex mixture of contents including diverse nucleic acid types (miRNA, LnRNA, siRNA, and DNA) and proteins; after binding to recipient cells the exosomes release their contents that execute their biological functions. Exosomes have been reported to play an important role in the tumorigenesis of TNBC, including tumor initiation, metastasis, angiogenesis, cell proliferation, immune escape, and drug resistance. On the other hand, exosomes can be valuable biomarkers for diagnosis, monitoring, and treatment of TNBC. More interestingly, exosomes can be harnessed as a nanosized drug-delivery system specifically targeting TNBC. In this review, we present the most recent mechanistic findings and clinical applications of exosomes in TNBC therapy, focusing on their use as diagnostic and prognostic biomarkers, nanoscale drug delivery platforms, and immunotherapeutic agents. In addition, the associated challenges and future directions of using exosomes for TNBC treatment will be discussed.

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