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1.
Phys Chem Chem Phys ; 26(4): 3159-3167, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38190261

RESUMO

A superior piezoelectric coefficient and diminutive lattice thermal conductivity are advantageous for the application of a two-dimensional semiconductor in piezoelectric and thermoelectric devices, whereas an imperfect piezoelectric coefficient and large lattice thermal conductivity limit the practical application of the material. In this study, we investigate how the equibiaxial strain regulates the electronic structure, and mechanical, piezoelectric, and thermal transport properties. Tensile strain can deduce the bandgap of the monolayer CrX2 (X = S, Se, Te), whereas compressive strain has an opposite effect. Additionally, the transition from a semiconductor to a metal state and the transition between direct and indirect band gaps will occur at appropriate strain values, so the electronic structure can be effectively regulated. The reason is the different sensitivities of the energy corresponding to K and Γ on the valence band to the strain due to the changes in different orbital overlaps. The tensile strain can effectively improve the flexibility of monolayers CrX2, which provides a possibility for the application of flexible electronic devices. Furthermore, the tensile strain can improve the piezoelectric strain coefficient of monolayers CrX2. Using Slacks formulation, we calculate the lattice thermal conductivity, and the tensile biaxial strain can reduce the lattice thermal conductivity. Our research provides a strategy to enhance the piezoelectric and flexible electronic applications and decrease the lattice thermal conductivity, which can benefit the thermoelectric applications.

2.
Phys Chem Chem Phys ; 25(15): 10827-10835, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37013675

RESUMO

In this paper, the electronic band structure, Rashba effect, hexagonal warping, and piezoelectricity of Janus group-VIA binary monolayers STe2, SeTe2, and Se2Te are investigated based on density functional theory (DFT). Due to the inversion asymmetry and spin-orbit coupling (SOC), the STe2, SeTe2 and Se2Te monolayers exhibit large intrinsic Rashba spin splitting (RSS) at the Γ point with the Rashba parameters 0.19 eV Å, 0.39 eV Å, and 0.34 eV Å, respectively. Interestingly, based on the k·p model via symmetry analysis, the hexagonal warping effect and a nonzero spin projection component Sz arise at a larger constant energy surface due to nonlinear k3 terms. Then, the warping strength λ was obtained by fitting the calculated energy band data. Additionally, in-plane biaxial strain can significantly modulate the band structure and RSS. Furthermore, all these systems exhibit large in-plane and out-of-plane piezoelectricity due to inversion and mirror asymmetry. The calculated piezoelectric coefficients d11 and d31 are about 15-40 pm V-1 and 0.2-0.4 pm V-1, respectively, which are superior to those of most reported Janus monolayers. Because of the large RSS and piezoelectricity, the studied materials have great potential for spintronic and piezoelectric applications.

3.
Environ Monit Assess ; 194(10): 737, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36068415

RESUMO

Solvents, components of pesticide emulsifiable concentrates (ECs), emit quantities of volatile organic compounds (VOCs) into the atmosphere. In the air, their active involvement in oxidative chemical reactions with oxidants exposed to ultraviolet solar radiation can result in the formation of ozone. The quantitative assessment of VOC emissions from agricultural pesticide applications remains hampered by many factors, especially the volatility coefficient of solvents in pesticides. Therefore, this study identified solvents in 20 widely used pesticide products in China. The volatility coefficients of the solvents were investigated based on a spraying test to evaluate VOC emissions from agricultural pesticide applications and their ozone formation potential (OFP). The results suggest that VOC emissions from agricultural pesticide applications amount to 0.60 Mt in 2017, with insecticides, fungicides, and herbicides contributing 0.39 Mt, 0.12 Mt, and 0.09 Mt of VOCs, respectively. Since VOC emission and maximum incremental reactivity (MIR) led to an OFP value (2.1 g ozone/g product) for insecticides, a primary consideration should be to decrease use of solvents with high volatility coefficients and large MIR values in insecticide products. This work could provide valuable insights regarding response options to reduce VOC emissions and ozone formation.


Assuntos
Poluentes Atmosféricos , Inseticidas , Ozônio , Praguicidas , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental/métodos , Ozônio/análise , Solventes , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
4.
Nanotechnology ; 32(45)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34348253

RESUMO

The design and search for efficient thermoelectric materials that can directly convert waste heat into electricity have been of great interest in recent years since they have practical applications in overcoming the challenges of global warming and the energy crisis. In this work, two new two-dimensional 1T-phase group-VI binary compounds Se2Te and SeTe2with outstanding thermoelectric performances are predicted using first-principles calculations combined with Boltzmann transport theory. The dynamic stability is confirmed based on phonon dispersion. It is found that the spin-orbit coupling effect has a significant impact on the band structure of SeTe2, and induces a transformation from indirect to direct band gap. The electronic and phononic transport properties of the Se2Te and SeTe2monolayer are calculated and discussed. High carrier mobility (up to 3744.321 and 2295.413 cm2V-1S-1for electron and hole, respectively) is exhibited, suggesting great applications in nanoelectronic devices. Furthermore, the maximum thermoelectric figure of meritzTof SeTe2for n-type and p-type is 2.88, 1.99 and 5.94, 3.60 at 300 K and 600 K, respectively, which is larger than that of most reported 2D thermoelectric materials. The surprising thermoelectric properties arise from the ultralow lattice thermal conductivitykl(0.25 and 1.89 W m-1K-1for SeTe2and Se2Te at 300 K), and the origin of ultralow lattice thermal conductivity is revealed. The present results suggest that 1T-phase Se2Te and SeTe2monolayer are promising candidates for thermoelectric applications.

5.
Phys Chem Chem Phys ; 23(47): 26955-26966, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34842246

RESUMO

Piezoelectric and thermoelectric materials that can directly convert mechanical and thermal energies into electricity have attracted great interest because of their practical applications in overcoming the challenges of the energy crisis. In this research, a new family of two-dimensional (2D) group-VI Janus ternary compounds with α and γ phases are predicted. After the stability testing, only the α-TeSSe monolayer has dynamic and thermal stability. The band structure and the optic, piezoelectric, and thermoelectric performances of the Janus α-TeSSe monolayer are calculated via first-principles calculations. Janus α-TeSSe is a narrow indirect bandgap semiconductor with a value of 0.953 eV at the HSE06 functional considering the spin-orbit coupling (SOC), which is beneficial to its thermoelectric performance, and its excellent absorption coefficients indicate that it may be a promising optoelectronic material. The piezoelectric calculations show that Janus α-TeSSe exhibits not only appreciable in-plane piezoelectricity (d11 = 17.17 pm V-1) but also superior vertical piezoelectricity (d31 = 0.22 pm V-1). Furthermore, a new TransOpt code is used to calculate the electrical transport coefficients with a constant electron-phonon coupling approximation, which is more accurate than the constant relaxation time approximation. The origin of ultralow lattice thermal conductivity is also discussed in detail. Finally, ultrahigh ZT values of 0.77 and 1.95 occur in n-type and p-type doping at 600 K, respectively, indicating that it is a promising thermoelectric material. Our work demonstrates that Janus α-TeSSe monolayers have potential applications in optoelectronic, piezoelectric, and thermoelectric devices, which will greatly stimulate research-related experiments.

6.
Med Sci Monit ; 27: e932404, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34493698

RESUMO

BACKGROUND Studies in ApoE knockout mice have shown that pseudolaric acid B (PB) can act as an immunomodulatory drug and attenuate atherosclerosis progression by modulating monocyte/macrophage phenotypes. Our previous study demonstrated that high salt intake could shift the phenotype of monocytes/macrophages to an inflammatory phenotype, and that this shift was related to hypertension and hypertensive left ventricular (LV) remodeling. However, no comprehensive assessment of the effects of PB on hypertensive LV remodeling has been conducted. MATERIAL AND METHODS In this study, RAW264.7 macrophages cultured with different concentrations of NaCl were used to investigate the modulating effects of PB on macrophage phenotype. Furthermore, N-nitro-L-arginine methyl ester hypertensive mice were used to investigate the modulating effects of PB on monocyte phenotype. LV remodeling was investigated by echocardiography. LV morphologic staining (for cardiomyocyte hypertrophy and collagen deposition) was performed at the time of sacrifice. RESULTS The results showed that PB significantly improved the viability of RAW264.7 cells, suppressed their phagocytic and migration abilities, and inhibited their phenotypic shift to M1 macrophages. In addition, the blood pressure of PB-treated mice was significantly decreased relative to that of control mice. Furthermore, after PB treatment, the percentage of Ly6Chi monocytes was significantly decreased while that of Ly6Clo monocytes was apparently increased. Moreover, PB preserved LV function and alleviated myocardial fibrosis and cardiomyocyte hypertrophy as measured at the end of the experimental period. The transfer of monocytes from PB-treated mice to hypertensive mice achieved the same effects. CONCLUSIONS Together, these findings indicate that PB exerts its protective effects on hypertensive LV remodeling by modulating monocyte/macrophage phenotypes and warrants further investigation.


Assuntos
Diterpenos/uso terapêutico , Ventrículos do Coração/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Cloreto de Sódio/efeitos adversos , Remodelação Ventricular/efeitos dos fármacos , Animais , Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Ecocardiografia , Hipertensão/induzido quimicamente , Hipertensão/imunologia , Hipertensão/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Fagocitose/efeitos dos fármacos , Fenótipo , Células RAW 264.7 , Remodelação Ventricular/imunologia
7.
Clin Exp Pharmacol Physiol ; 47(12): 1953-1964, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32687618

RESUMO

Destruction of endothelial cells (ECs) function is involved in the structural and functional pathophysiological processes of preeclampsia (PE). Vascular endothelial injury may pre-exist for several years in women that develop PE and may pose increased risks for hypertension, coronary artery disease, and type-2 diabetes mellitus. Previous findings showed that Elabela (ELA), the endogenous ligand of the apelin (APJ) receptor expressed mainly on ECs, may play a protective role in early pregnancy and prevent PE. However, the exact functional role and molecular mechanisms of ELA are unclear. Here, we aimed to classify whether and how ELA improves EC function via the ELA-APJ axis. Two human umbilical vein endothelial cell (HUVEC) lines, namely HUVECs and EA.hy926, were treated with ELA, and then their cellular activities were studied by performing CCK-8 tests, scratch-wound analysis, and tube-formation assays. Doses of ELA exceeding 0.01 µmol/L markedly improved the cell viability, migration, and tube formation ability of HUVECs and EA.hy926 cells. Western blot analysis indicated that the above effects caused by ELA were related to upregulation of the APJ receptor and activation of PI3K/Akt signalling. Further verification tests were performed using the PI3K inhibitor wortmannin, and the results illustrated that inhibiting PI3K/Akt signalling blocked the positive effects of ELA on EC function and APJ receptor expression. Taken together, our findings indicate that ELA may alter EC function via the ELA-APJ axis and PI3K/Akt signalling and that ELA shows promise for use in endothelial dysfunction therapy for preventing and treating PE.


Assuntos
Células Endoteliais da Veia Umbilical Humana , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Feminino , Humanos , Pré-Eclâmpsia/metabolismo , Gravidez
8.
Emerg Infect Dis ; 24(12): 2371-2373, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30457543

RESUMO

We detected Chuzan virus (CHUV) in domestic yaks from the Qinghai-Tibetan Plateau, western China, indicating CHUV probably has been transmitted to yaks in recent years. Awareness for CHUV surveillance and transmission and livestock health management in these special regions should be raised to avoid outbreaks and animal loss.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/virologia , Vírus Palyam , Infecções por Reoviridae/veterinária , Animais , Bovinos , China/epidemiologia , Genes Virais , Genoma Viral , Geografia Médica , Vírus Palyam/classificação , Vírus Palyam/genética , Filogenia , RNA Viral
9.
Cell Physiol Biochem ; 45(4): 1590-1602, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29486482

RESUMO

BACKGROUND/AIMS: Cell cycle checkpoint kinase 2 (CHK2) performs essential cellular functions and might be associated with tumorigenesis and tumor progression. Here, we explored the function and molecular mechanisms of CHK2 in the progression of papillary thyroid cancer (PTC). METHODS: The expression levels of both total CHK2 and activated CHK2 (p-CHK2) in tissues from 100 PTC patients were detected and evaluated using immunohistochemistry. The roles of CHK2 on cell proliferation, invasion, migration, apoptosis and cancer stem cell (CSC) markers were investigated by CCK-8, Transwell, flow cytometry, western blot and ALDEFLOUR assay. PTC cells cultured in suspension conditions were assayed for anoikis. The anchorage-independent condition was further detected by soft agar colony formation assay. Furthermore, anoikis associated regulatory proteins were explored by western blot and verified by forced downregulation experiment, respectively. RESULTS: We found that the levels of both CHK2 and p-CHK2 were significantly upregulated in PTC cancer tissues compared with those in tumor-adjacent tissues. The overexpression of p-CHK2 in primary tumor tissues was associated with tumor aggressiveness and metastatic potential. However, the levels of both CHK2 and p-CHK2 were decreased in metastatic lymph nodes. Our results showed that CHK2 upregulated the levels of CSC markers with no effect on cell proliferation, invasion and migration. Interestingly, we revealed a previously undescribed anoikis-promoting role for CHK2 in PTC. Specifically, the detachment of PTC cells from the extracellular matrix (ECM) triggers CHK2 degradation. Then, the forced downregulation of CHK2 rescued PTC cells from anoikis, but no effect was observed on the apoptosis of adherent PTC cells. Additionally, as a novel regulator of anoikis, CHK2 can induce cell death in a p53-independent manner via the regulation of PRAS40 activation. CONCLUSION: High expression levels of CHK2 and p-CHK2 were associated with the progression of PTC. Our results defined an unexpected role for CHK2 as a mediator of anoikis that functions through the regulation of PRAS40 activation, which may be associated with the survival of circulating tumor cells and metastatic behavior.


Assuntos
Anoikis , Carcinoma Papilar/patologia , Quinase do Ponto de Checagem 2/metabolismo , Neoplasias da Glândula Tireoide/patologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Carcinoma Papilar/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Quinase do Ponto de Checagem 2/antagonistas & inibidores , Quinase do Ponto de Checagem 2/genética , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosforilação , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima
10.
Ann Surg Oncol ; 24(8): 2189-2198, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27913945

RESUMO

BACKGROUND: The use of prophylactic central neck dissection (pCND) for papillary thyroid cancer (PTC) without clinical evidence of nodal metastasis (cN0) remains controversial. This study was designed to examine whether pCND for PTC affected locoregional recurrence (LRR). METHODS: A systematic review was performed to compare the LRR between patients with PTC who underwent total thyroidectomy (TT) and pCND and those who underwent TT alone. The primary outcome was LRR. Other outcomes, including postoperative radioiodine (RAI) ablation and surgically related complications, were evaluated. A meta-analysis was performed using the random-effects model. RESULTS: We included 17 studies, which comprised 4437 patients. Patients in the TT+pCND group had a significantly reduced risk of LRR (risk ratio [RR] = 0.66; 95% confidence interval [CI]: 0.49-0.90; P = 0.008). The LRR in the central neck compartment (RR = 0.35; 95% CI 0.18-0.68; P = 0.002) was significantly lower in the TT+pCND group, whereas the LRR in the lateral neck compartment was similar between the two groups. Compared with the TT alone group, patients in the TT+pCND group tended to receive higher RAI (74.6% vs. 59.9%) and experience temporary hypocalcemia (odds ratio [OR] = 2.37; 95% CI 1.89-2.96; P < 0.00001), permanent hypocalcemia (OR = 1.93; 95% CI 1.05-3.57; P = 0.03), and increased overall morbidity (OR = 2.56; 95% CI 1.75-3.74; P < 0.00001). CONCLUSIONS: This meta-analysis suggested that although pCND reduced the LRR in PTC-specifically in the central neck compartment-it was accompanied by an increased rate of postoperative hypocalcemia. However, the evidence is limited and randomized, controlled trials are needed to clarify this role further.


Assuntos
Carcinoma Papilar/cirurgia , Recidiva Local de Neoplasia/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Carcinoma Papilar/patologia , Humanos , Esvaziamento Cervical , Recidiva Local de Neoplasia/patologia , Prognóstico , Neoplasias da Glândula Tireoide/patologia
11.
Muscle Nerve ; 49(3): 325-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24464710

RESUMO

Lambert-Eaton myasthenic syndrome (LEMS) is an autoimmune disorder characterized by autoantibodies against presynaptic voltage-gated calcium channels that impair neuromuscular transmission. Malignancies, especially small cell lung cancer (SCLC), have been associated with LEMS and account for approximately 60% of cases, making malignancy management a central step in LEMS therapy. In addition, immunosuppressive therapy is also recommended for symptomatic control. Interestingly, both pathological and epidemiological data suggest that the autoimmune response can inhibit progression of tumors in malignancy-associated LEMS. Thus, conventional broad-spectrum immunosuppressants may not be effective agents for treatment of LEMS, especially in those with malignancy-associated LEMS. Recent preclinical and clinical studies have indicated that proteasome inhibitors can eliminate antibody-producing cells efficiently, block dendritic cell maturation, and have anti-tumor activity. We hypothesize that proteasome inhibitors may be promising agents for treatment of malignancy-related LEMS.


Assuntos
Síndrome Miastênica de Lambert-Eaton/tratamento farmacológico , Inibidores de Proteassoma/uso terapêutico , Animais , Células Apresentadoras de Antígenos/efeitos dos fármacos , Autoanticorpos/imunologia , Humanos , Síndrome Miastênica de Lambert-Eaton/imunologia
12.
J Hazard Mater ; 479: 135696, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39217940

RESUMO

The widespread application of pesticides in China has led to the accumulation of residues in soil. However, few regional studies have fully elucidated the characteristics of pesticide residues in soil (PRS) and the associated risks to the ecosystem and human health on a national level. Therefore, this study aims to compile a dataset on PRS in China from 2006 to 2020 and analyze the interactions and impacts between PRS and the environment. The average concentration of PRS in China was 243.96 µg/kg which was lower than the levels reported in Euro-Americans and other nations. This study revealed PRS in China predominantly originates from organochlorine pesticide residues, with DDTs and HCHs being significant contributors. Despite the high intensity of pesticide application in the Southeast China, PRS concentrations were comparable to those in the Northeast, due to environmental factors that favor pesticide degradation in the Southeast. Both legacy and in-use pesticides were transported by surface runoff or air current, resulting in their accumulation in soil of the lower Yangtze River basin or the piedmont soil of Qinling Mountains, respectively. The average soil environment carrying capacity of PRS in China was -69.5 kg. The ecological risk contributed by PRS in China was mainly at a negligible level. Carcinogenic risks of PRS to adults (4.6 ×10-4) and children (6 ×10-4) exceeded the tolerable thresholds (10-5) by a small margin.


Assuntos
Resíduos de Praguicidas , Poluentes do Solo , China , Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Medição de Risco , Humanos , Monitoramento Ambiental , Solo/química , Hidrocarbonetos Clorados/análise
13.
J Hazard Mater ; 465: 133385, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38160558

RESUMO

Volatile organic compounds (VOCs) are considered as important precursors of ozone in the air, while the contribution of VOCs from pesticide application (PVOCs) to ozone production is unknown. Utilizing data from the Ministry of Agriculture and Rural Affairs of the People's Republic of China and ChinaCropPhen1km, this paper developed PVOC emission inventories with a resolution of 1 km for the main crops (rice, maize, and wheat) from 2012 to 2019 in China. The results revealed that pesticide application is an important VOC emission source in China. Specially, the PVOC emissions from the major grain-producing regions in June accounted for approximately 30% of the annual total PVOC emissions in the local regions. The simulation with the Weather Research and Forecasting Community Multiscale Air Quality model (WRF-CMAQ) indicated that the PVOC emissions increased the mean maximum daily 8-hour average (MDA8) ozone concentration across China by 2.5 ppb in June 2019. During the same period, PVOCs in the parts of North China Plain contributed 10% of the ozone formation. Under the comprehensive emission reduction scenario, it is anticipated that by 2025, the joint implementation of measures including reducing pesticide application, improving pesticide utilization efficiency and promoting solvent substitution will decrease PVOC emissions by 60% compared with 2019, thereby mitigating ozone pollution.

14.
J Cell Biochem ; 114(5): 1020-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23129128

RESUMO

Kallikrein-binding protein (KBP) was previously identified as a serpin family member with specific inhibitory effect on tissue kallikrein and angiogenesis, while there is little knowledge about the effects on inflammation. The aim of this study is to investigate whether KBP can suppress LPS-induced inflammatory process. Our results showed that both recombinant KBP and KBP overexpression inhibited LPS-stimulated TNF-α transcription and translation in macrophage cell line RAW264.7 and primary macrophages. Furthermore, KBP treatment protected mice from endotoxin shock and repressed serum TNF-α production, increasing survival rate of mice from 10% to 50% when compared to LPS alone. Moreover, qPCR and Western blot analysis demonstrated that both suppressor of cytokine signaling 3 (SOCS3) transcription and translation were induced by KBP treatment in the present of LPS. RNA interference assay and luciferase assay showed that SOCS3 was responsible for the down-regulation of TNF-α by KBP, rather than NF-κB subunit p65 and ß-catenin. Therefore, we demonstrated that KBP suppressed LPS-induced TNF-α production via upregulating SOCS3 expression. These results present the protective effects of KBP on LPS-induced inflammation and provide novel information for the anti-inflammation mechanism.


Assuntos
Lipopolissacarídeos/farmacologia , Serpinas/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Regulação para Cima/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Endotoxinas/administração & dosagem , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Ratos , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética , Análise de Sobrevida , Transcrição Gênica/efeitos dos fármacos , beta Catenina/metabolismo
16.
Neuromodulation ; 16(5): 436-41; discussion 441-2, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23601088

RESUMO

OBJECTIVES: Eddy currents in the metal shell and copper losses in the coils generate heat in rechargeable neurostimulators, which increases the temperature of the adjacent tissue, potentially causing thermal damage of implant patients. Hence, there is an urgent need for a simple self-help method to measure the temperature of such subcutaneous devices. MATERIALS AND METHODS: A wireless rechargeable implant system was fabricated and tested with in vivo experiments in swine to measure the increasing temperatures of both the implant device and the adjacent skin. A total of three swine were used in the study with 13 wireless charging tests. RESULTS: It was found that the temperatures of both the implant and the skin rose consistently with an approximately linear relationship in most of the charging time, demonstrating that the neurosimulator temperature could be estimated from the skin temperature. The equilibrium temperature differences are all less than 2°C. CONCLUSIONS: A convenient method was then given to monitor the adjacent skin temperature to evaluate the thermal hazards with a skin temperature threshold of 41°C. The proposed approach can be easily implemented by an implant patient at home to reduce the thermal risk, ease patient anxiety, and improve clinical outcomes.


Assuntos
Queimaduras por Corrente Elétrica/etiologia , Fontes de Energia Elétrica/efeitos adversos , Neuroestimuladores Implantáveis/efeitos adversos , Temperatura Cutânea/fisiologia , Animais , Suínos , Temperatura , Fatores de Tempo
17.
Chemosphere ; 316: 137814, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36638924

RESUMO

To improve the ecological environment, provinces in China have set ambitious goals for the electrification of fossil-fuel-powered vehicles (FVs) and the promotion of electric vehicles (EVs). Hainan is the first province to propose a clean energy target that schedules the banning of new FVs sales from 2030. Therefore, Hainan is a good case study to illustrate how this policy might improve regional air quality over the coming years. This study first developed an anthropogenic emission inventory of seven major air pollutants in 2017 in Hainan. The total emissions of CO, NOx, NH3, volatile organic compounds (VOCs), PM10 and PM2.5 and SO2 in 2017 were estimated as 247.56, 69.61, 61.87, 41.38, 37.02, 19.82, and 8.55 kt, respectively. Using the developed emission inventory, multiple scenarios of economic development were considered to assess the benefits to air quality from Hainan's goal of electrification. In comparison with 2017, the reductions in emissions of SO2, NOx, CO, PM10, PM2.5, VOCs, and NH3 by 2045 were projected to be 5.45 (11.11%), 275.07 (57.32%), 675.51 (34.07%), 8.39 (5.73%), 7.73 (8.24%), 81.15 (9.76%), and 4.89 (0.91%) kt, respectively, under the all-electric vehicle scenarios. These results indicate that this policy will not only reduce the emission of air pollutants but also avoid complex O3 pollution in the future. The findings of this work elucidate the effects of vehicle electrification policies on regional air quality and provide scientific support for policymakers in developing pollution control strategies.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Poluição do Ar/análise , China , Monitoramento Ambiental , Material Particulado/análise , Melhoria de Qualidade , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
18.
World J Gastrointest Oncol ; 15(9): 1644-1652, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37746653

RESUMO

BACKGROUND: Endoscopic mucosal resection is an innovative method for treating early gastric cancer and has been widely used in clinical practice. AIM: To analyze the factors associated with the development of heterochronic gastric cancer in patients with early gastric cancer who had undergone endoscopic mucosal dissection (EMD). METHODS: A cohort of patients with early gastric cancer treated using EMD was retrospectively analyzed, and patients who developed heterochronic gastric cancer after the surgery were compared with those who did not. The effects of patient age, sex, tumor size, pathological type, and surgical technique on the development of heterochronic gastric cancer were assessed using statistical analysis. RESULTS: Of the 300 patients with early gastric cancer, 150 patients developed heterochronic gastric cancer after EMD. Statistical analysis revealed that patient age (P value = XX), sex (P value = XX), tumor size (P value = XX), pathological type (P value = XX), and surgical technique (P value = XX) were significantly associated with the occurrence of heterochronic gastric cancer. CONCLUSION: Age, sex, tumor size, pathological type, and surgical technique are key factors influencing the occurrence of heterochronic gastric cancer after EMD in patients with early gastric cancer. To address these factors, postoperative follow-up and management should be strengthened to improve the prognosis and survival rate of patients.

19.
Hypertens Pregnancy ; 42(1): 2256863, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37735976

RESUMO

BACKGROUND: Preeclampsia (PE) mainly occurs in pregnant women and is hereditary. Several genome-wide association studies (GWAS) on Caucasian samples have reported some gene loci that are associated with preeclampsia. However, these studies have not reached consistent conclusions. No previous GWAS has examined preeclampsia in the Chinese Han population. METHOD: This study aimed to identify common genetic variations associated with preeclampsia in the Chinese Han population through two-stage case‒control studies. The discovery cohort included 92 patients with severe preeclampsia and 187 healthy controls. The validation cohort included 52 patients with preeclampsia and 104 controls. A genome-wide association study was performed to identify putative preeclampsia genes in the discovery cohort, with validation in the validation cohort. RESULTS: In the discovery cohort, GWAS demonstrated that 19 single-nucleotide polymorphisms (SNPs) were associated with preeclampsia (P < 10-5). The pathway analysis revealed that these 19 SNP representative genes were mainly enriched in the adenylyl cyclase-inhibiting G-protein coupled receptor signaling pathway. After validation in the validation cohort, rs13176432 and rs13210237 remained closely related to preeclampsia (P<0.05). In the combined data set, the frequency of the G allele in rs13176432 was significantly higher in cases with preeclampsia than in controls (P = 5 × 10-6). The frequency of the A allele in rs13210237 was higher in the preeclampsia group (P = 8 × 10-6). The rs13210237 representative genes include HSF2 and GJA1, while the rs13176432 representative gene is TRIM36. There were no differences in genotype distribution between the early-onset and late-onset preeclampsia groups (P > 0.05). Furthermore, rs13210237 and rs13176432 were related to preeclampsia in the adjusted regression model (P < 0.000). CONCLUSION: In this study of two independent cohorts, we found that rs13210237 and rs13176432 might be novel preeclampsia-susceptible genetic factors in the Han population in China. However, there was no association between the onset of preeclampsia and these genotypes.


Assuntos
Estudo de Associação Genômica Ampla , Pré-Eclâmpsia , Humanos , Feminino , Gravidez , Pré-Eclâmpsia/genética , Alelos , Genótipo , China , Proteínas de Choque Térmico , Fatores de Transcrição , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Conexina 43
20.
Exp Ther Med ; 25(4): 148, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36911373

RESUMO

The role of autophagy in high-salt (HS) intake associated hypertensive left ventricular (LV) remodeling remains unclear. The present study investigated the LV autophagic change and its association with the hypertensive LV remodeling induced by chronic HS intake in spontaneously hypertensive rats (SHR). Wistar Kyoto (WKY) rats and SHR were fed low-salt (LS; 0.5% NaCl) and HS (8.0% NaCl) diets and were subjected to invasive LV hemodynamic analysis after 8, 12 and 16 weeks of dietary intervention. Reverse transcription-quantitative PCR and western blot analysis were performed to investigate the expression of autophagy-associated key components. The LV morphologic staining was performed at the end of the study. The rat H9c2 ventricular myoblast cell-associated experiments were performed to explore the mechanism of HS induced autophagic change. A global autophagy-associated key component, as well as increased cardiomyocyte autophagic vacuolization, was observed after 12 weeks of HS intake. During this period, the heart from HS-diet-fed SHR exhibited a transition from compensated LV hypertrophy to decompensation, as shown by progressive impairment of LV function and interstitial fibrosis. Myocardial extracellular [Na+] and the expression of tonicity-responsive enhancer binding protein (TonEBP) was significantly increased in HS-fed rats, indicating myocardial interstitial hypertonicity by chronic HS intake. The global autophagic change and overt deterioration of LV function were not observed in LS-fed SHR and HS-fed WKY rats. The study of rat H9c2 cardiomyocytes demonstrated a cytosolic [Na+] elevation-mediated, reactive oxygen species-dependent the autophagic change occurred when exposed to an increased extracellular [Na+]. The present findings demonstrated that a myocardial autophagic change participates in the maladaptive LV remodeling induced by chronic HS intake in SHR, which provides a possible target for future intervention studies on HS-induced hypertensive LV remodeling.

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