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1.
Biomark Med ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639733

RESUMO

Background: The present meta-analysis aimed to explore the association between C-reactive protein (CRP) levels and the prognosis of patients with endometrial cancer (EC). Methods: The effect of CRP level on predicting overall survival (OS) and disease-free survival (DFS) in patients with EC was evaluated according to pooled hazard ratios (HRs) and corresponding 95% CIs. Results: High CRP levels were not significantly correlated with OS (HR: 1.32 [95% CI: 0.99-1.77]; p = 0.060) or DFS (HR: 1.05 [95% CI: 0.88-1.25]; p = 0.597) in patients with EC. Conclusion: CRP levels did not significantly predict OS or DFS in patients with EC. However, according to subgroup analyses, higher CRP levels were significantly associated with poor OS in Asian patients with EC.

2.
Science ; 383(6687): eadk8838, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38452087

RESUMO

Crop yield potential is constrained by the inherent trade-offs among traits such as between grain size and number. Brassinosteroids (BRs) promote grain size, yet their role in regulating grain number is unclear. By deciphering the clustered-spikelet rice germplasm, we show that activation of the BR catabolic gene BRASSINOSTEROID-DEFICIENT DWARF3 (BRD3) markedly increases grain number. We establish a molecular pathway in which the BR signaling inhibitor GSK3/SHAGGY-LIKE KINASE2 phosphorylates and stabilizes OsMADS1 transcriptional factor, which targets TERMINAL FLOWER1-like gene RICE CENTRORADIALIS2. The tissue-specific activation of BRD3 in the secondary branch meristems enhances panicle branching, minimizing negative effects on grain size, and improves grain yield. Our study showcases the power of tissue-specific hormonal manipulation in dismantling the trade-offs among various traits and thus unleashing crop yield potential in rice.


Assuntos
Brassinosteroides , Grão Comestível , Oryza , Proteínas de Plantas , Brassinosteroides/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Regulação da Expressão Gênica de Plantas , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
Adv Mater ; : e2314380, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517171

RESUMO

Triboelectric nanogenerator (TENG) manifests distinct advantages such as multiple structural selectivity, diverse selection of materials, environmental adaptability, low cost, and remarkable conversion efficiency, which becomes a promising technology for micro-nano energy harvesting and self-powered sensing. Tribo-dielectric materials are the fundamental and core components for high-performance TENGs. In particular, the charge generation, dissipation, storage, migration of the dielectrics, and dynamic equilibrium behaviors determine the overall performance. Herein, a comprehensive summary is presented to elucidate the dielectric charge transport mechanism and tribo-dielectric material modification principle toward high-performance TENGs. The contact electrification and charge transport mechanism of dielectric materials is started first, followed by introducing the basic principle and dielectric materials of TENGs. Subsequently, modification mechanisms and strategies for high-performance tribo-dielectric materials are highlighted regarding physical/chemical, surface/bulk, dielectric coupling, and structure optimization. Furthermore, representative applications of dielectric materials based TENGs as power sources, self-powered sensors are demonstrated. The existing challenges and promising potential opportunities for advanced tribo-dielectric materials are outlined, guiding the design, fabrication, and applications of tribo-dielectric materials.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38421390

RESUMO

OBJECTIVE: The objective of this study was to analyze the ratio of fracture site diameter to tibial isthmus diameter (TFI ratio) as a predictor of postoperative complications, including malunion and delayed union, after tibial intramedullary nailing for middle and lower tibial fractures. METHODS: Data were collected from all adult patients older than 20 years of age who underwent tibial intramedullary nailing for middle and lower tibial fractures between January 2015 and January 2023 and were followed up for at least 1 year. Diabetes history, smoking history, fracture type, injury mechanism, surgical method, surgical approach, diameter of the medullary cavity at the fracture site, and diameter of the tibial isthmus were recorded. Logistic regression analysis was used to determine the variables affecting the occurrence of complications. The TFI ratio was used to calculate the sensitivity and specificity of the parameters, and ROC curves were generated to establish TFI ratio thresholds for predicting complications. RESULTS: A total of 123 patients with middle and lower tibial fractures were treated with intramedullary nails. The mean age of the patients was 43.72 years (range, 21-81 years); 89 were males, and 34 were females. Univariate logistic regression analysis showed that fracture type, open reduction surgery, superior patellar approach, and TFI ratio were significantly correlated with postoperative complications after intramedullary nailing of a tibial fracture. Multivariate logistic regression analysis showed that the TFI ratio was an independent risk factor for complications (P = 0.001*). By using the TFI ratio as a predictor of complications, an ROC curve was generated to establish a threshold. The ROC curve showed that a TFI ratio ≥ 1.31 had a sensitivity of 0.89, a specificity of 0.71, and an area under the ROC curve of 0.82 for predicting complications. CONCLUSIONS: The results of this study suggest that a wider intramedullary diameter and a shorter fixed length at the fracture site are associated with a higher incidence of complications after tibial intramedullary nailing. The TFI ratio may be used as a reliable parameter for predicting complications after such surgery. In patients with a high TFI ratio (≥ 1.31), additional reduction and fixation techniques may be needed to obtain and maintain fracture reduction.

5.
Adv Sci (Weinh) ; 11(13): e2307382, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38240464

RESUMO

Heat dissipation performance is crucial for the operational reliability of industrial equipment, which can be monitored by detecting the wind or airflow temperature of the radiator. The emergence of triboelectric nanogenerators (TENGs) provides new routes for wind energy harvesting and self-powered sensing. Herein, a rotary wind-driven triboelectric nanogenerator (RW-TENG) with soft-contact working mode is newly designed to achieve tunable contact areas by utilizing the reliable thermal response of NiTi shape memory alloy (SMA) to air/wind temperature. The RW-TENG can generate different triboelectric outputs under air stimulation with different speeds or temperatures, which is demonstrated as a power source for online monitoring sensors, self-powered wind speed sensing, and airflow temperature monitoring. Specifically, a self-powered sensor of wind speed is demonstrated with a sensitivity of 0.526 µA m-1 s between 2.2 and 19.6 m s-1, and a self-powered monitoring device of high airflow temperature, which show relatively short response time (109 s), strong anti-interference ability and outstanding long-term durability. This study introduces an innovative route for real-time detection of airflow temperature in wind-cooled industrial equipment, showing broad application prospects for information perception and intelligent sensing of the industrial IoTs.

6.
Sci Total Environ ; 916: 170271, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38262248

RESUMO

The global warming and other environmental problems caused by SF6 emissions can be reduced due to the widespread use of eco-friendly insulating gas, perfluoropentanone (C5F10O). However, there is an exposure risk to populations in areas near C5F10O equipment, so it is important to clarify its biosafety and pathogenesis before large-scale application. In this paper, histopathology, transcriptomics, 4D-DIA proteomics, and LC-MS metabolomics of rats exposed to 2000 ppm and 6000 ppm C5F10O are analyzed to reveal the mechanisms of toxicity and health risks. Histopathological shows that inflammatory cell infiltration, epithelial cell hyperplasia, and alveolar atrophy accompanied by alveolar wall thickening are present in both low-dose and high-dose groups. Analysis of transcriptomic and 4D-DIA proteomic show that Cell cycle and DNA replication can be activated by both 2000 ppm and 6000 ppm C5F10O to induce cell proliferation. In addition, it also leads to the activation of pathways such as Antigen processing and presentation, Cell adhesion molecules and Complement and coagulation cascades, T cell receptor signal path, Th1 and T cell receptor signal path, Th1 and Th2 cell differentiation, complement and coagulation cascades. Finally, LC-MS metabolomics analysis confirms that the metabolic pathways associated with glycerophospholipids, arachidonic acid, and linoleic acid are disrupted and become more severe with increasing doses. The mechanism of lung toxicity caused by C5F10O is systematically expounded based on the multi-omics analysis and provided biosafety references for further promotion and application of C5F10O.


Assuntos
Pneumopatias , Proteômica , Ratos , Animais , Pulmão , Receptores de Antígenos de Linfócitos T
7.
Acta Obstet Gynecol Scand ; 103(5): 917-926, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38146139

RESUMO

INTRODUCTION: Emergency cervical cerclage is a recognized method for preventing mid-trimester pregnancy loss and premature birth; however, its benefits remain controversial. This study aimed to establish preoperative models predicting preterm birth and gestational latency following emergency cervical cerclage in singleton pregnant patients with a high risk of preterm birth. MATERIAL AND METHODS: We retrospectively reviewed data from patients who received emergency cerclage between 2015 and 2023 in three institutions. Patients were grouped into a derivation cohort (n = 141) and an independent validation cohort (n = 61). Univariate and multivariate logistic and Cox regression analyses were used to identify independent predictive variables and establish the models. Harrell's C-index, time-dependent receiver operating characteristic curves and areas under the curves, calibration curve, and decision curve analyses were performed to assess the models. RESULTS: The models incorporated gestational weeks at cerclage placement, history of prior second-trimester loss and/or preterm birth, cervical dilation, and preoperative C-reactive protein level. The C-index of the model for predicting preterm birth before 28 weeks was 0.87 (95% CI: 0.82-0.93) in the derivation cohort and 0.82 (95% CI: 0.71-0.92) in the independent validation cohort; The C-index of the model for predicting gestational latency was 0.70 (95% CI: 0.66-0.75) and 0.78 (95% CI: 0.71-0.84), respectively. In the derivation set, the areas under the curves were 0.84, 0.81, and 0.84 for predicting 1-, 3- and 5-week pregnancy prolongation, respectively. The corresponding values for the external validation were 0.78, 0.78, and 0.79, respectively. Calibration curves showed a good homogeneity between the observed and predicted ongoing pregnant probabilities. Decision curve analyses revealed satisfactory clinical usefulness. CONCLUSIONS: These novel models provide reliable and valuable prognostic predictions for patients undergoing emergency cerclage. The models can assist clinicians and patients in making personalized clinical decisions before opting for the cervical cerclage.


Assuntos
Cerclagem Cervical , Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Nascimento Prematuro/prevenção & controle , Cerclagem Cervical/métodos , Estudos Retrospectivos , Segundo Trimestre da Gravidez , Prognóstico
8.
J Endovasc Ther ; : 15266028231220322, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38158706

RESUMO

OBJECTIVE: To conduct a meta-analysis to assess the safety and efficacy of t-Branch off-the-shelf multibranched endograft for the treatment of thoracoabdominal aortic aneurysm (TAAA). DATA SOURCES: PubMed, Embase, and Web of Science. REVIEW METHODS: Online databases were searched from June 2012 to March 2023. The data were pooled together using a random-effects model of proportions. The outcomes overall included technical success, spinal cord ischemia, target vessel occlusion, type I or III endoleak, reintervention, early mortality (30-day), and mid-term outcomes. Subgroup meta-analyses and meta-regression were performed to explore variation among studies. RESULTS: A total of 15 studies containing 1238 patients were included in the meta-analysis. The overall study quality assessment was found to be moderate to good. The pooled technical success was 97.0% (95% confidence interval [CI]=95.5-98.6, I2=53.01%, 1185/1238 cases, 15 studies). Overall, early mortality was 7.3% (95% CI=4.4-10.1, I2=74.48%, 124/1238 cases, 15 studies). Early spinal cord ischemia was 13.4% (95% CI=9.6-17.2, I2=67.24%, 160/1238 cases, 15 studies), and early type I or III endoleak was 6.0% (95% CI=3.4-8.5, I2=53.71%, 68/1032 cases, 9 studies). Mid-term outcomes showed target vessel occlusion was 4% (95% CI=1.4-6.5, I2=65.18%, 28/528 cases, 10 studies, 5-21.2 months), type I or III endoleak was 4.7% (95% CI=2-7.5, I2=49.74%, 38/512 cases, 10 studies, 5-21.2 months), reintervention was 11.2% (95% CI=8.1-14.3, I2=31.06%, 85/650 cases, 10 studies, 5-21.2 months), and pooled mortality was 13.9% (95% CI=7.2-20.7, I2=76.32%, 84/550 cases, 11 studies, 5-21.2 months). Meta-regression found a significant linear association between higher technical success and earlier publication year (p=0.014) and studies with anatomic inclusion criteria (p=0.037). Urgent patients (p=0.021) and later publication year (p=0.048) were significantly associated with higher early mortality. CONCLUSION: The use of the off-the-shelf t-Branch multibranched endograft for elective or urgent endovascular TAAA repair is associated with high technical success rates and proved to be safe and effective at early and mid-term follow-up. However, the heterogeneity between the included studies is high, and prospective, randomized studies along with future larger studies with long-term follow-up are needed. CLINICAL IMPACT: The Zenith t-Branch (Cook Medical, Bloomington, Ind) was approved as a commercially available device in Europe in June 2012. Although a decade has past, the outcomes of t-Branch have rarely been synthesized at the global level. This meta-analysis included 15 studies containing 1238 patients. The meta-analyses included technical success, major adverse events, reintervention, early mortality, and mid-term outcomes. The outcome was very meaningful and representative for the use of t-Branch. It is helpful for endovascular surgeons to make decisions on the treatment of TAAA patients.

9.
Food Chem Toxicol ; 182: 114196, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37992955

RESUMO

α-Amanitin, the primary lethal toxin of Amanita, specifically targets the liver, causing oxidative stress, hepatocyte apoptosis, and irreversible liver damage. As little as 0.1 mg/kg of α-amanitin can be lethal for humans, and there is currently no effective antidote for α-amanitin poisoning. Cannabidiol is a non-psychoactive natural compound derived from Cannabis sativa that exhibits a wide range of anti-inflammatory, antioxidant, and anti-apoptotic effects. It may play a protective role in preventing liver damage induced by α-amanitin. To investigate the potential protective effects of cannabidiol on α-amanitin-induced hepatocyte apoptosis and oxidative stress, we established α-amanitin exposure models using C57BL/6J mice and L-02 cells in vitro. Our results showed that α-amanitin exposure led to oxidative stress, apoptosis, and DNA damage in both mouse hepatocytes and L-02 cells, resulting in the death of mice. We also found that cannabidiol upregulated the level of Nrf2 and antioxidant enzymes, alleviating apoptosis, and oxidative stress in mouse hepatocytes and L-02 cells and increasing the survival rate of mice. Our findings suggest that cannabidiol has hepatoprotective effects through the regulation of Nrf2 and antioxidant enzymes and may be a potential therapeutic drug for Amanita poisoning.


Assuntos
Alfa-Amanitina , Canabidiol , Humanos , Animais , Camundongos , Alfa-Amanitina/metabolismo , Alfa-Amanitina/farmacologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Canabidiol/farmacologia , Canabidiol/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Camundongos Endogâmicos C57BL , Fígado , Apoptose , Estresse Oxidativo , Hepatócitos
10.
Int J Biol Macromol ; 253(Pt 5): 127222, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37797846

RESUMO

The rapid development of modern electrical engineering puts forward urgent demand for high-performance electrical insulating materials. In this study, inspired by the layered structure of natural nacre, we present a novel biomimetic composite insulating film (referred to as M/C film) that is derived from agricultural waste corncobs and industrial waste mica tailings through a sol-gel-film transformation process. The novel insulating film has excellent tensile strength (94 MPa), high dielectric strength (68 kV mm-1), low dielectric loss, good heat resistance (T0 = 235 °C), and excellent UV shielding properties. Meanwhile, the M/C film presents environmental impacts much lower than those petrochemical-based plastic film as it can be 100 % recycled in a closed-loop recycling process and easily biodegraded in the environment (lignocellulose goes back to the carbon cycle and the mica return to the geological cycle). It is a potential alternative for petrochemical plastics and provides a possible way to utilize agricultural waste and mica tailings.


Assuntos
Silicatos de Alumínio , Lignina , Resistência à Tração
11.
Adv Mater ; 35(48): e2307003, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37748200

RESUMO

The integration of electronic effects into complexes for the construction of novel materials has not yet attracted significant attention in the field of energy storage. In the current study, eight one-dimensional (1D) nickel-based salicylic acid  complexes (Ni-XSAs, X = pH, pMe, pMeO, mMe, pBr, pCl, pF, and pCF3 ), are prepared by ligand engineering. The coordination environments in the Ni-XSAs are explored using X-ray absorption fine structure spectroscopy. The charge transfer of the complexes is modulated according to the difference in the electron-donating ability of the substituents, in combination with frontier orbital theory. Furthermore, density functional theory is used to investigate the effect of the substituent position on the electronic properties of the complexes. Ni-mMeSA exhibits better electrical conductivity than Ni-pMeSA. The electrochemical performance of Ni-mMeSA as an aqueous battery cathode is remarkably improved with a maximum energy density of 0.30 mWh cm-2 (125 Wh kg-1 ) and a peak power density of 33.72 mW cm-2 (14.03 kW kg-1 ). This study provides ideas for the application of new coordination chemistry in the field of energy materials science.

12.
Artigo em Inglês | MEDLINE | ID: mdl-37713223

RESUMO

Existing works mainly focus on crowd and ignore the confusion regions which contain extremely similar appearance to crowd in the background, while crowd counting needs to face these two sides at the same time. To address this issue, we propose a novel end-to-end trainable confusion region discriminating and erasing network called CDENet. Specifically, CDENet is composed of two modules of confusion region mining module (CRM) and guided erasing module (GEM). CRM consists of basic density estimation (BDE) network, confusion region aware bridge and confusion region discriminating network. The BDE network first generates a primary density map, and then the confusion region aware bridge excavates the confusion regions by comparing the primary prediction result with the ground-truth density map. Finally, the confusion region discriminating network learns the difference of feature representations in confusion regions and crowds. Furthermore, GEM gives the refined density map by erasing the confusion regions. We evaluate the proposed method on four crowd counting benchmarks, including ShanghaiTech Part_A, ShanghaiTech Part_B, UCF_CC_50, and UCF-QNRF, and our CDENet achieves superior performance compared with the state-of-the-arts.

13.
J Low Genit Tract Dis ; 27(4): 331-336, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37589311

RESUMO

OBJECTIVE: This study aimed to investigate the triage value obtained in DNA ploidy analysis of cervical exfoliated cells in women with high-risk human papillomavirus (HR-HPV)-positive status in the primary screening of cervical cancer. METHODS: The authors selected 3,000 HR-HPV-positive women for cervical exfoliated cell sampling and conducted DNA ploidy analysis, liquid-based cytology (LBC), colposcopy, and cervical biopsy. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of high-grade squamous intraepithelial lesion (HSIL)-positive detection between DNA ploidy analysis and LBC were compared according to histopathology diagnosis as the golden criteria, and the efficacy of predicting HSIL-positive immediate risk was evaluated. RESULTS: A total of 2,892 HR-HPV-positive women were enrolled in the investigation. For HSIL+ women, the DNA ploidy group showed a significantly higher sensitivity (CIN2+: 79.21% vs 65.35%, p = .022; CIN3+: 81.48% vs 70.37%, p = .013), lower specificity (CIN2+: 85.00% vs 96.59%, p < .001; CIN3+: 84.14% vs 93.41%, p < .001), and lower PPV (CIN2+: 16.23% vs 29.33%, p = .001; CIN3+: 8.92% vs 16.89%, p = .002) compared with the LBC group, whereas the NPV showed no significant difference. Compared with LBC alone in diagnosing HSIL, DNA ploidy combined with LBC showed higher specificity (CIN2+: 99.21% vs 96.59%, p = .003; CIN3+: 96.48% vs 93.41%, p < .001) and higher PPV (CIN2+: 41.35% vs 29.33%, p = .022; CIN3+: 24.81% vs 16.89%, p = .028), whereas no significant difference was observed in the sensitivity (CIN2+: 54.46% vs 65.35%, p = .063; CIN3+: 61.11% vs 70.37%, p = .221) and NPV ( p > .05). Among the HR-HPV-positive women positive for DNA ploidy, the imminent risk of CIN2+ and CIN3+ were 15.62% and 8.92%, respectively, above the threshold for the colposcopy positive rate. Among the positive cases both for DNA ploidy and the LBC result of negative for intraepithelial lesion or malignancy, the immediate risk of CIN3+ was 3.31%, below the threshold for colposcopy positive rate. Besides, for women with LBC result of ASC-US and above, the immediate risk of CIN3+ was greater than 4%. CONCLUSIONS: The DNA ploidy analysis can be used as an effective triage method for HR-HPV-positive women during the primary screening of cervical cancer, although it can provide higher specificity when combined with LBC and reduce the referral rate for colposcopy.


Assuntos
Carcinoma in Situ , Carcinoma de Células Escamosas , Infecções por Papillomavirus , Lesões Intraepiteliais Escamosas , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico , Papillomavirus Humano , Infecções por Papillomavirus/diagnóstico , Triagem , Ploidias , DNA
14.
Sensors (Basel) ; 23(15)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37571631

RESUMO

To meet the real demand for broadband full-band high-gain antenna sensors in the process of partial discharge (PD) Ultra-High frequency (UHF) detection test and online monitoring of power equipment, this paper builds a resonant cavity monopole UHF antenna sensor based on Fabry-Perot resonant cavity antenna technology, conducts the sensor Voltage Standing Wave Ratio (VSWR) optimization study using curved flow technology, conducts the sensor gain optimization study using slot dual resonant structure, and, finally, tests the sensor performance using the built PD detection test platform. The resonant cavity monopole antenna exhibits outstanding VSWR performance in the frequency range of 0.37 GHz-3 GHz, according to simulation and test data: the average gain in the frequency range of 0.3 GHz-3 GHz is 4.92 dBi, and the highest gain at the primary resonant frequency of 1.0 GHz is 7.16 dBi, with good radiation performance over the whole frequency spectrum. The electromagnetic pulse signal sensed by the UHF sensor developed in this paper can demonstrate the energy spectrum distribution characteristics of PD radiation electromagnetic wave signal more comprehensively, laying a firm technical foundation for thoroughly understanding the electromagnetic wave radiation characteristics of various types of PD insulation defects of various power equipment and the selection of a specific direction for its supporting optimization.

15.
ISA Trans ; 142: 693-701, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37500412

RESUMO

Herein we first introduce the relationship between the photoacoustic (PA) signals' intensity of hydrogen sulfide (H2S) versus multiple parameters of optical path conditions, following by the construction of response surface method (RSM)-based models of the PA signals' intensity versus the distance l1 from the laser head to the convex lens, the distance l2 from the convex lens to the PA cell (PAC), and the distance l3 from the geometric center line of the light beam to the acoustic sensor. After that, we perform the significance analysis. The results show that the RSM model with a third-order configuration is relatively preferred. The distances l1, l2 and l3 all have significant influences on the PA signals' intensity. Additionally, we ameliorated the performance of the full third-order model by removing the non-significant terms.

16.
Sensors (Basel) ; 23(10)2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37430636

RESUMO

Spiral antenna sensors are commonly used in partial discharge (PD) ultra-high frequency (UHF) detection in gas-insulated switchgears (GISs). However, most of the existing UHF spiral antenna sensors are based on a rigid base and balun, such as FR-4. The safe built-in installation of antenna sensors requires the complex structural transformation of GISs. To solve this problem, a low-profile spiral antenna sensor is designed based on a polyimide (PI) flexible base, and its performance is optimized by improving the clearance ratio. The simulation and measurement results show that the profile height and diameter of the designed antenna sensor is 0.3 mm and 137 mm, which is 99.7% and 25.4% smaller than the traditional spiral antenna. Under a different bending radius, the antenna sensor can maintain VSWR ≤ 5 in 650 MHz~3 GHz, and its maximum gre is up to 6.1 dB. Finally, the PD detection performance of the antenna sensor is carried out on a real 220 kV GIS. The results show that, after being built in, the PD with a weak discharge magnitude of 4.5 pC can be effectively detected by the antenna sensor, and the antenna sensor has the ability to quantify the severity of PD. In addition, through the simulation, the antenna sensor has potential for the detection of micro water in GISs.

17.
Toxicol Lett ; 383: 89-97, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37329965

RESUMO

Amanitin poisoning is one of the most life-threatening mushroom poisonings. α-Amanitin plays a key role in Amanita phalloides intoxication. α-Amanitin shows toxic effects on the liver. However, the mechanism by which α-amanitin induces liver injury has not been elucidated. Autophagy plays a crucial role in maintaining cellular homeostasis and is closely related to the occurrence of a variety of diseases. Studies have shown that autophagy may play an important role in the process of α-amanitin-induced liver injury. However, the mechanism of α-amanitin-induced autophagy remains unclear. Thus, this study aimed to explore the mechanisms of α-amanitin in inducing hepatotoxicity in Sprague Dawley (SD) rats and the normal human liver cell line L02 cells. The SD rats and L02 cells exposed to α-amanitin were observed to determine whether α-amanitin could induce the autophagy of rat liver and L02 cells. The regulatory relationship between autophagy and the AMPK-mTOR-ULK pathway by exposing the autophagy agonist (rapamycin (RAPA)), autophagy inhibitor (3-methylademine (3-MA)), and AMPK inhibitor (compound C) was also explored. Autophagy-related proteins and AMPK-mTOR-ULK pathway-related proteins were detected using Western blot. The results of the study indicated that exposure to different concentrations of α-amanitin led to morphological changes in liver cells and significantly elevated levels of ALT and AST in the serum of SD rats. Additionally, the expression levels of LC3-II, Beclin-1, ATG5, ATG7, AMPK, p-AMPK, mTOR, p-mTOR, and ULK1 were significantly increased in the rat liver. And we found that L02 cells exposed to 0.5 µM α-amanitin for 6 h significantly induced autophagy and activated the AMPK-mTOR-ULK1 pathway. Pretreated with RAPA, 3-MA, and compound C for 1 h, the expression levels of autophagy-related proteins and AMPK-mTOR-ULK pathway-related proteins significantly changed. Our results indicates that autophagy and the AMPK-mTOR-ULK pathway are involved in the process of α-amanitin-induced liver injury. This study may foster the identification of actionable therapeutic targets for A. phalloides intoxication.


Assuntos
Proteínas Quinases Ativadas por AMP , Doença Hepática Crônica Induzida por Substâncias e Drogas , Ratos , Animais , Humanos , Proteínas Quinases Ativadas por AMP/metabolismo , Alfa-Amanitina , Ratos Sprague-Dawley , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Transdução de Sinais , Proteínas Relacionadas à Autofagia , Autofagia , Hepatócitos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
18.
ACS Omega ; 8(12): 11414-11424, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37008096

RESUMO

The C4F7N/CO2/O2 gas mixture received a great deal of attention for its potential use in eco-friendly gas-insulated equipment (GIE). The evaluation of the compatibility between C4F7N/CO2/O2 and sealing rubber is necessary and significant considering the high working pressure (0.14-0.6 MPa) of GIE. Herein, we explored the compatibility between C4F7N/CO2/O2 and fluororubber (FKM) and nitrile butadiene rubber (NBR) for the first time by analyzing the gas components, rubber morphology, elemental composition, and mechanical properties. The interaction mechanism of the gas-rubber interface was further investigated based on the density functional theory. We found that C4F7N/CO2/O2 is compatible with FKM and NBR at 85 °C, while the surface morphology changed at 100 °C, with white granular and agglomerated lumps appearing on FKM and multi-layer flakes being generated on NBR. The accumulation of the fluorine element occurred, and the compressive mechanical properties of NBR deteriorated after the gas-solid rubber interaction. Overall, the compatibility between FKM and C4F7N/CO2/O2 is superior, which could be employed as the sealing material for C4F7N-based GIE.

19.
Acta Biomater ; 166: 524-535, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37088161

RESUMO

Cerebral ischemia-reperfusion injury (CIRI) is a complex pathological condition with high mortality. In particular, reperfusion can stimulate overproduction of reactive oxygen species (ROS) and activation of inflammation, causing severe secondary injuries to the brain. Despite tremendous efforts, it remains urgent to rationally design antioxidative agents with straightforward and efficient ROS scavenging capability. Herein, a potent antioxidative agent was explored based on iridium oxide nano-agglomerates (Tf-IrO2 NAs) via the facile transferrin (Tf)-templated biomineralization approach, and innovatively applied to treat CIRI. Containing some small-size IrO2 aggregates, these NAs possess intrinsic hydroxyl radicals (•OH)-scavenging ability and multifarious enzyme activities, such as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx). Moreover, they also showed improved blood-brain barrier (BBB) penetration and enhanced accumulation in the ischemic brain via Tf receptor-mediated transcytosis. Therefore, Tf-IrO2 NAs achieved robust in vitro anti-inflammatory and cytoprotection effects against oxidative stress. Importantly, mice were effectively protected against CIRI by enhanced ROS scavenging activity in vivo, and the therapeutic mechanism was systematically verified. These findings broaden the idea of expanding Ir-based NAs as potent antioxidative agents to treat CIRI and other ROS-mediated diseases. STATEMENT OF SIGNIFICANCE: (1) The ROS-scavenging activities of IrO2 are demonstrated comprehensively, which enriched the family of nano-antioxidants. (2) The engineering Tf-IrO2 nano-agglomerates present unique multifarious enzyme activities and simultaneous transferrin targeting and BBB crossing ability for cerebral ischemia-reperfusion injury therapy. (3) This work may open an avenue to enable the use of IrO2 to alleviate ROS-mediated inflammatory and brain injury diseases.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Camundongos , Animais , Espécies Reativas de Oxigênio/metabolismo , Transferrina/farmacologia , Irídio/farmacologia , Irídio/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/patologia , Estresse Oxidativo , Antioxidantes/farmacologia , Reperfusão
20.
J Endovasc Ther ; : 15266028231159245, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36942722

RESUMO

OBJECTIVE: Type II endoleak (T2EL) worsens the long-term results of endovascular aneurysm repair (EVAR). How to prevent T2ELs remains controversial. This study aimed to evaluate the efficacy and safety of fibrin glue sac filling (FGSF) to prevent T2ELs after EVAR. METHODS: A prospective randomized controlled trial was conducted. Patients were randomly divided into group A (standard EVAR + FGSF) and group B (standard EVAR). The follow-up plans included outpatient or telephone consultation at 1 and 3 months and computed tomography (CT) angiography at 6 months, 1 year, and once a year after EVAR. RESULTS: A total of 64 abdominal aortic aneurysm (AAA) patients were randomized to the 2 groups. All patients were followed up for more than 6 months. The 2 groups showed similar baseline characteristics. The rate of T2ELs on immediate angiography in group A (9.6%) was significantly lower than that in group B (33.3%, p=0.033). Moreover, the sac area change was significantly reduced in group A at 6 months after EVAR (p=0.021). However, T2EL incidence was similar at the 6-month (p=0.055) and 1-year (p=0.057) follow-ups, and AAA diameter change was also similar at 1 year. There were similar operation times, radiation doses, severe adverse events (SAEs), and reinterventions between the 2 groups. CONCLUSION: Fibrin glue sac filling could prevent short-term type II endoleaks and promote AAA shrinkage after 6 months. The FGSF procedure is swift and straightforward; however, patients are at risk of bowel ischemia, especially after previous bowel resections or concomitant superior mesenteric artery (SMA) disease. CLINICAL IMPACT: Standard endovascular aneurysm repair (EVAR) couldn't prevent type II endoleak (T2EL). In this study, we found fibrin glue sac filling (FGSF) could prevent T2EL and promote AAA shrinkage in a short term. And the FGSF procedure is easy, it will be a useful supplement to standard EVAR for clinicians. And FGSF might have potential usefulness on ruptured aneurysms, although without direct evidence.Fibrin glue is often used to hemostasis and tissue adhesion in surgical patients and burn patients, we firstly carry out a randomized controlled study and prove that fibrin glue sac filling could prevent T2EL and promote sac remodeling.

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