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2.
Front Pharmacol ; 14: 1291900, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026966

RESUMO

Background: Surgical patients with aortic dissection often require multiple antihypertensive drugs to control blood pressure. However, the prescription pattern and effectiveness of antihypertensive drugs for these patients are unclear. We aimed to investigate the prescription pattern and effectiveness of different classes of antihypertensive drugs in surgical patients with aortic dissection. Methods: Newly diagnosed aortic dissection patients who underwent surgery, aged >20 years, from 1 January 2012 to 31 December 2017 were identified. Patients with missing data, in-hospital mortality, aortic aneurysms, or congenital connective tissue disorders, such as Marfan syndrome, were excluded. Prescription patterns of antihypertensive drugs were identified from medical records of outpatient visits within 90 days after discharge. Antihypertensive drugs were classified into four classes: 1) ß-blockers, 2) calcium channel blockers (CCBs), 3) renin-angiotensin system, and 4) other antihypertensive drugs. Patients were classified according to the number of classes of antihypertensive drugs as follows: 1) class 0, no exposure to antihypertensive drugs; 2) class 1, antihypertensive drugs of the same class; 3) class 2, antihypertensive drugs of two classes; 4) class 3, antihypertensive drugs of three classes; or 5) class 4, antihypertensive drugs of four classes. The primary composite outcomes included rehospitalization associated with aortic dissection, death due to aortic dissection, and all-cause mortality. Results: Most patients were prescribed two (28.87%) or three classes (28.01%) of antihypertensive drugs. In class 1, ß-blockers were most commonly used (8.79%), followed by CCBs (5.95%). In class 2, ß-blockers+CCB (10.66%) and CCB+RAS (5.18%) were the most common drug combinations. In class 3, ß-blockers + CCB+RAS (14.84%) was the most prescribed combination. Class 0 had a significantly higher hazard of the composite outcome (HR, 2.1; CI, 1.46-3.02; p < 0.001) and all-cause mortality (HR, 2.34; CI, 1.56-3.51; p < 0.001) than class 1. There were no significant differences in hazards for rehospitalization associated with aortic dissection among classes. Conclusion: Among operated patients with type A aortic dissection, no specific type of antihypertensive drug was associated with a better outcome, whereas among those with type B aortic dissection, the use of ß-blockers and CCBs was related to a significantly lower risk of the composite outcome.

3.
J Clin Med ; 12(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36902749

RESUMO

INTRODUCTION: Aortic dissection (AD) is a life-threatening disease. However, the effectiveness of different strategies of antihypertensive therapies in non-operated AD patients is still unclear. MATERIALS AND METHODS: Patients were classified into five groups (groups 0-4) based on the number of classes of antihypertensive drugs, including ß-blockers, renin-angiotensin system (RAS) agents (angiotensin-converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), and the renin-inhibitors), calcium channel blockers (CCBs), and other antihypertensive drugs, were prescribed within 90 days after discharge. The primary endpoint was a composite outcome of re-hospitalization associated with AD, referral for aortic surgery, and all-cause death. RESULTS: A total of 3932 non-operated AD patients were included in our study. The most prescribed antihypertensive drugs were CCBs, followed by ß-blockers and ARBs. Within group 1, compared to other antihypertensive drugs, patients using RAS agents (aHR, 0.58; p = 0.005) had a significantly lower risk of occurrence of the outcome. Within group 2, the risk of composite outcomes was lower in patients using ß-blockers + CCBs (aHR, 0.60; p = 0.004) or CCBs + RAS agents (aHR, 0.60; p = 0.006) than in those using RAS agents + others. CONCLUSION: For non-operated AD patients, RAS agents, ß-blockers, or CCBs should be given in a different strategy of combinations to reduce the hazard of AD-related complications compared to other agents.

4.
Ying Yong Sheng Tai Xue Bao ; 34(1): 169-177, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36799391

RESUMO

Habitat quality assessment provides an effective interface for exploring the mechanisms linking land use change and biodiversity. We used InVEST model to assess the spatial and temporal variations of habitat quality in the Pearl River source area from 2000 to 2020, and to examine the impacts of land use change on habitat quality. The results showed that during the study period, construction land had the largest change, with an area increase of 321.48 km2, and the area of grassland decreased most significantly. Habitat quality in the Pearl River source area was generally at a high level, with a small downward trend. The low value areas were concentrated in the town centers and main agricultural production areas, while habitat quality was high in the mountainous areas in the south and north region. The cold spots of habitat quality change had the most significant aggregation effect in the Quzhan Basin along the Nanpan River. The number of hot spots was small and scattered. Among the various types of nature reserves, habitat quality of Jiache Nature Reserve in Huize County was the lowest, and that of Zhujiangyuan Nature Reserve had a slight decreasing trend, mainly due to the transformation of grassland to cropland. The contribution of habitat quality degradation driven by land function change was 5.6 times as that of improvement. The encroachment of urban and rural construction space into grassland ecological space and agricultural production space was the dominant factor driving the reduction of habitat quality in the Pearl River source area. The contribution of construction land expansion decreased from 69.9% (2000-2010) to 46.7% (2010-2020). The expansion of construction land was the main cause for the degradation of habitat quality. The degradation threat from arable land expansion overtook the traffic network construction as the secondary threat source from 2010 to 2020. It was necessary to increase control of nature reserves in the Pearl River source area and to implement land use regulation strictly to guarantee no net loss and integrity of the ecosystem.


Assuntos
Ecossistema , Rios , China , Cidades , Biodiversidade , Conservação dos Recursos Naturais
5.
ACS Appl Mater Interfaces ; 12(3): 3670-3680, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31872995

RESUMO

Na3V2(PO4)2O2F (NVPOF) is attracting great interest due to its large capacity and high working voltage. However, poor electronic conductivity limits the electrochemical performance of NVPOF. Herein, we fabricate N/P-dual-doped carbon-coated NVPOF microspheres (labeled as NVPOF@P/N/C) via a hydrothermal process followed by heat treatment. This microsphere-structured NVPOF@P/N/C composite has a relatively high tap density of 1.22 g/cm3. TEM and XPS results reveal that the dual-doped carbon layer is tightly coated on the NVPOF surface due to the bridging effect of P and has a good protective effect on NVPOF. Density functional theory (DFT) calculations confirm that a N/P-dual-doped carbon layer is advantageous to achieve higher electronic conductivity and lower migration activation energy than those of the undoped and single N- or P-doped carbon layer. As a cathode material for a sodium-ion battery (SIB), NVPOF@P/N/C exhibits high capacity (128 mAh/g at 0.5 C and 122 mAh/g at 2 C) and ultralong cycle performance (only 0.037% capacity fading rate per cycle in 500 cycles at 2 C). We believe that the NVPOF@P/N/C composite is appealing for high-performance SIBs with large energy density.

6.
ACS Appl Mater Interfaces ; 10(43): 36851-36859, 2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30295456

RESUMO

Nitrogen-doped carbon-covered Na3V2(PO4)2F3 (NVPF/C-PDPA) composites have been successfully prepared by self-polymerization of dopamine on the NVPF surface and subsequent sintering. The X-ray diffraction results show that the NVPF/C-PDPA has good crystallinity and introducing dopamine does not affect the lattice structure of NVPF. The high-resolution transmission electron microscopy, high-angle annular dark-field images, and energy dispersive X-ray spectroscopy analyses reveal that the NVPF/C-PDPA particles are covered by a complete and uniform covering layer, which is effective at preventing corrosion of NVPF in the electrolyte to greatly increase cycling stability. Furthermore, N-doping into the carbon layer can produce additional active sites to improve the capacity especially the rate capacity. Such a NVPF/C-PDPA electrode delivers a remarkable rate capacity (98.0 mA h g-1 at 10 C) and superior cycle performance (∼95.8% capacity retention at 10 C after 800 cycles). We believe that this work may be beneficial for accelerating the development of high-performance electrode materials and the commercialization of Na-ion batteries.

7.
Pak J Pharm Sci ; 28(4 Suppl): 1551-3, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26431665

RESUMO

Objective of the study was to investigate the expression and significance of XIAP and c-jun in Condyloma acuminatum. The immunohistochemistry SABC method was adopted to detect the expression of XIAP and c-jun in Condyloma acuminatum. The positive expression rate of XIAP and c-jun in Condyloma acuminatum was 80% (32/40) and 90% (36/40) separately and the intensity of expression was usually ++ ~ +++. While in control group, the positive expression rate of XIAP and c-jun was 27.8% (5/18) and 16.7 % (3/18) separately, and the intensity of expression was - ~ ++. There was statistical significance of the positive expression rate and the expression intensity of XIAP and c-jun between the two groups (P<0.05). Besides, the positive correlation existed between expression of XIAP and c-jun (r=0.306 P<0.01). The over-expression of XIAP and c-jun in Condyloma acuminatum may be associated with the growth of Condyloma acuminatum.


Assuntos
Condiloma Acuminado/metabolismo , Proteínas Proto-Oncogênicas c-jun/análise , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/análise , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Nanoscale ; 7(33): 13981-90, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26228305

RESUMO

Due to their excellent anti-oxidation performance, CeO2 nanoparticles receive wide attention in pharmacological application. Deep understanding of the anti-oxidation mechanism of CeO2 nanoparticles is extremely important to develop potent CeO2 nanomaterials for anti-oxidation application. Here, we report a detailed study on the anti-oxidation process of CeO2 nanoparticles. The valence state and coordination structure of Ce are characterized before and after the addition of H2O2 to understand the anti-oxidation mechanism of CeO2 nanoparticles. Adsorbed peroxide species are detected during the anti-oxidation process, which are responsible for the red-shifted UV-vis absorption spectra of CeO2 nanoparticles. Furthermore, the coordination number of Ce in the first coordination shell slightly increased after the addition of H2O2. On the basis of these experimental results, the reactivity of coordination sites for peroxide species is considered to play a key role in the anti-oxidation performance of CeO2 nanoparticles. Furthermore, we present a robust method to engineer the anti-oxidation performance of CeO2 nanoparticles through the modification of the defect state and reducibility by doping with Gd(3+). Improved anti-oxidation performance is also observed in cell culture, where the biocompatible CeO2-based nanoparticles can protect INS-1 cells from oxidative stress induced by H2O2, suggesting the potential application of CeO2 nanoparticles in the treatment of diabetes.


Assuntos
Cério/química , Nanopartículas/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Complexos de Coordenação/química , Gadolínio/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/toxicidade , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Espectroscopia Fotoeletrônica , Ratos , Espécies Reativas de Oxigênio/química , Análise Espectral Raman , Espectroscopia por Absorção de Raios X
9.
Chem Commun (Camb) ; 51(9): 1608-11, 2015 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-25501620

RESUMO

Carbon coated K0.8Ti1.73Li0.27O4 (KTLO) has been synthesized by a facile flux method followed by ball-milling and gaseous carbon coating. The carbon coated KTLO delivers a reversible specific capacity of 119.6 mA h g(-1) at 20 mA g(-1) with no capacity loss after 250 cycles as an anode material in sodium ion batteries, exhibiting an improved rate capability of 66 mA h g(-1) at 200 mA g(-1). It was found that carbon coating of KTLO not only enhances its electronic conductivity, but also improves the structure stability, proving that the carbon coated KTLO is a promising anode material for sodium ion batteries.

10.
Sci Rep ; 4: 5064, 2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-24860942

RESUMO

Cadmium-incorporated Li2FeSiO4/C composites have been successfully synthesized by a solid-state reaction assisted with refluxing. The effect and mechanism of Cd-modification on the electrochemical performance of Li2FeSiO4/C were investigated in detail by X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, Raman spectra, transmission electron microscopy, positron annihilation lifetime spectroscopy and Doppler broadening spectrum, and electrochemical measurements. The results show that Cd not only exists in an amorphous state of CdO on the surface of LFS particles, but also enters into the crystal lattice of LFS. Positron annihilation lifetime spectroscopy and Doppler broadening spectrum analyses verify that Cd-incorporation increases the defect concentration and the electronic conductivity of LFS, thus improve the Li(+)-ion diffusion process. Furthermore, our electrochemical measurements verify that an appropriate amount of Cd-incorporation can achieve a satisfied electrochemical performance for LFS/C cathode material.

11.
ACS Appl Mater Interfaces ; 5(23): 12304-9, 2013 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-24195648

RESUMO

Reduced graphene oxide modified Li2FeSiO4/C (LFS/(C+rGO)) composite is successfully synthesized by a citric-acid-based sol-gel method and evaluated as cathode material for lithium ion batteries. The LFS/(C+rGO) shows an improved electronic conductivity due to the conductive network formed by reduced graphene oxide nanosheets and amorphous carbon in particles. Electrochemical impedance spectroscopy results indicate an increased diffusion coefficient of lithium ions (2.4 × 10(-11) cm(2) s(-1)) for LFS/(C+rGO) electrode. Compared with LFS with only amorphous carbon, the LFS/(C+rGO) electrode exhibits higher capacity and better cycling stability. It delivers a reversible capacity of 178 mAh g(-1) with a capacity retention ratio of 94.5% after 40 cycles at 0.1 C, and an average capacity of 119 mAh g(-1) at 2 C. The improved performance can be contributed to the reduced crystal size, good particle dispersion, and the improved conductive network between LFS particles.

12.
Sci Rep ; 3: 1125, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23350032

RESUMO

A cobalt-based thermoelectric compound Ca(3)Co(2)O(6) (CCO) has been developed as new cathode material with superior performance for intermediate-temperature (IT) solid-oxide fuel cell (SOFC). Systematic evaluation has been carried out. Measurement of thermal expansion coefficient (TEC), thermal-stress (σ) and interfacial shearing stress (τ) with the electrolyte show that CCO matches well with several commonly-used IT electrolytes. Maximum power density as high as 1.47 W cm(-2) is attained at 800°C, and an additional thermoelectric voltage of 11.7 mV is detected. The superior electrochemical performance, thermoelectric effect, and comparable thermal and mechanical behaviors with the electrolytes make CCO to be a promising cathode material for SOFC.

13.
ACS Appl Mater Interfaces ; 4(6): 3047-53, 2012 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-22658801

RESUMO

Three types of MnO2 nanostructures, viz., α-MnO2 nanotubes, hollow ß-MnO2 bipyramids, and solid ß-MnO2 bipyramids, have been synthesized via a simple template-free hydrothermal method. Cyclic voltammetry and galvanostatic charge/discharge measurements demonstrate that the hollow ß-MnO2 bipyramids exhibit the highest specific capacity and the best cyclability; the capacity retains 213 mAh g(-1) at a current density of 100 mA g(-1) after 150 cycles. XRD patterns of the lithiated ß-MnO2 electrodes clearly show the expansion of lattice volume caused by lithiation, but the structure keeps stable during lithium insertion/extraction process. We suggest that the excellent performance for ß-MnO2 can be attributed to its unique electrochemical reaction, compact tunnel-structure and hollow architecture. The hollow architecture can accommodate the volume change during charge/discharge process and improve effective diffusion paths for both lithium ions and electrons.


Assuntos
Fontes de Energia Elétrica , Lítio/química , Compostos de Manganês/química , Óxidos/química , Técnicas Eletroquímicas , Eletrodos , Íons/química , Nanotubos/química
14.
Adv Mater ; 24(15): 2047-50, 2012 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-22422374

RESUMO

Nitrogen-doped carbon nanofiber webs (CNFWs) with high surface areas are successfully prepared by carbonization-activation of polypyrrole nanofiber webs with KOH. The as-obtained CNFWs exhibit a superhigh reversible capacity of 943 mAh g(-1) at a current density of 2 A g(-1) even after 600 cycles, which is ascribed to the novel porous nanostructure and high-level nitrogen doping.


Assuntos
Carbono/química , Fontes de Energia Elétrica , Lítio/química , Nanofibras/química , Nanotecnologia/métodos , Nitrogênio/química , Capacitância Elétrica , Eletrodos , Porosidade , Propriedades de Superfície
15.
J Am Chem Soc ; 128(45): 14454-5, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17090017

RESUMO

Multiferroic rare-earth manganates TbMn2O5 and TbMnO3 were synthesized selectively via a one-pot hydrothermal route. The different morphologies can be obtained by changing the ratio of reactants MnCl2.4H2O and KMnO4. SEM and TEM images showed a high quality for the products that was also confirmed by XPS patterns and Raman spectra.

16.
Science ; 312(5771): 254-7, 2006 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-16614219

RESUMO

Extensive efforts to develop a solid-oxide fuel cell for transportation, the bottoming cycle of a power plant, and distributed generation of electric energy are motivated by a need for greater fuel efficiency and reduced air pollution. Barriers to the introduction of hydrogen as the fuel have stimulated interest in developing an anode material that can be used with natural gas under operating temperatures 650 degrees C < T < 1000 degrees C. Here we report identification of the double perovskites Sr2Mg(1-x)MnxMoO(6-delta) that meet the requirements for long-term stability with tolerance to sulfur and show a superior single-cell performance in hydrogen and methane.

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