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1.
Artículo en Inglés | MEDLINE | ID: mdl-38700967

RESUMEN

We consider a robust dynamic event-driven control (EDC) problem of nonlinear systems having both unmatched perturbations and unknown styles of constraints. Specifically, the constraints imposed on the nonlinear systems' input could be symmetric or asymmetric. Initially, to tackle such constraints, we construct a novel nonquadratic cost function for the constrained auxiliary system. Then, we propose a dynamic event-triggering mechanism relied on the time-based variable and the system states simultaneously for cutting down the computational load. Meanwhile, we show that the robust dynamic EDC of original nonlinear-constrained systems could be acquired by solving the event-driven optimal control problem of the constrained auxiliary system. After that, we develop the corresponding event-driven Hamilton-Jacobi-Bellman equation, and then solve it through a unique critic neural network (CNN) in the reinforcement learning framework. To relax the persistence of excitation condition in tuning CNN's weights, we incorporate experience replay into the gradient descent method. With the aid of Lyapunov's approach, we prove that the closed-loop auxiliary system and the weight estimation error are uniformly ultimately bounded stable. Finally, two examples, including a nonlinear plant and the pendulum system, are utilized to validate the theoretical claims.

2.
New Phytol ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38515244

RESUMEN

Hydrolyzable tannins (HTs), predominant polyphenols in oaks, are widely used in grape wine aging, feed additives, and human healthcare. However, the limited availability of a high-quality reference genome of oaks greatly hampered the recognition of the mechanism of HT biosynthesis. Here, high-quality reference genomes of three Asian oak species (Quercus variabilis, Quercus aliena, and Quercus dentata) that have different HT contents were generated. Multi-omics studies were carried out to identify key genes regulating HT biosynthesis. In vitro enzyme activity assay was also conducted. Dual-luciferase and yeast one-hybrid assays were used to reveal the transcriptional regulation. Our results revealed that ß-glucogallin was a biochemical marker for HT production in the cupules of the three Asian oaks. UGT84A13 was confirmed as the key enzyme for ß-glucogallin biosynthesis. The differential expression of UGT84A13, rather than enzyme activity, was the main reason for different ß-glucogallin and HT accumulation. Notably, sequence variations in UGT84A13 promoters led to different trans-activating activities of WRKY32/59, explaining the different expression patterns of UGT84A13 among the three species. Our findings provide three high-quality new reference genomes for oak trees and give new insights into different transcriptional regulation for understanding ß-glucogallin and HT biosynthesis in closely related oak species.

3.
Endokrynol Pol ; 75(1): 71-82, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38497392

RESUMEN

INTRODUCTION: Obesity not only affects human health but also is an important risk factor for a variety of chronic diseases. Therefore, it is particularly important to analyse the epidemic trend of obesity and actively carry out the prevention and control of obesity in the population. MATERIAL AND METHODS: A total of 4565 adults were selected by multi-stage stratified random sampling in Shenmu, Shaanxi Province, China. Univariate analysis was used to explore the epidemic characteristics of obesity in this region. Multivariate logistic regression was used to analyse the relationship between obesity and chronic diseases. Finally, the prediction efficiency of different obesity indexes was analysed by drawing receiver operator characteristic curves (ROC). All statistical analysis was completed by SPSS 26.0 software. RESULTS: The prevalence rates of overweight, obesity, and central obesity were 39.9%, 18.2%, and 48.0%, respectively. After adjusting for other confounding factors, multivariate logistic regression analysis showed that overweight and obesity were risk factors for hypertension, dyslipidaemia, and hyperuricaemia. Central obesity is a risk factor for dyslipidaemia and hyperuricaemia. High level of waist-to-height ratio (WHtR) was a risk factor for dyslipidaemia and hyperuricaemia (p < 0.05). Obesity-related indicators: body mass index (BMI), waist circumference (WC), and WHtR, are strongly correlated with the increased risk of chronic diseases in northern Shaanxi, China. The optimal BMI cut-off values for predicting hypertension, dyslipidaemia, and hyperuricaemia were 24.27, 24.04, and 25.54, respectively. The optimal WC cut-off values for predicting dyslipidaemia and hyperuricaemia were 84.5 and 90.5, and WHtR cut-off values were 0.52 and 0.54, respectively. CONCLUSION: The problem of overweight, obesity, and central obesity in adults is serious in northern Shaanxi, China. Obesity of all types will increase the risk of chronic diseases. Therefore, a variety of preventive and therapeutic measures should be adopted to curb obesity and reduce the incidence of related chronic diseases.


Asunto(s)
Dislipidemias , Hipertensión , Hiperuricemia , Adulto , Humanos , Obesidad Abdominal/epidemiología , Obesidad Abdominal/complicaciones , Sobrepeso/complicaciones , Hiperuricemia/epidemiología , Hiperuricemia/complicaciones , Prevalencia , Obesidad/complicaciones , Dislipidemias/complicaciones , China/epidemiología
4.
World J Gastrointest Surg ; 16(2): 438-450, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38463372

RESUMEN

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR), a composite inflammatory biomarker, is associated with the prognosis in patients with colorectal tumors. However, whether the NLR can be used as a predictor of symptomatic postoperative anastomotic leakage (AL) in elderly patients with colon cancer is unclear. AIM: To assess the role of the NLR in predicting the occurrence of symptomatic AL after surgery in elderly patients with colon cancer. METHODS: Data from elderly colon cancer patients who underwent elective radical colectomy with anastomosis at three centers between 2018 and 2022 were retrospectively analyzed. Receiver operating characteristic curve analysis was performed to determine the best predictive cutoff value for the NLR. Twenty-two covariates were matched using a 1:1 propensity score matching method, and univariate and multivariate logistic regression analyses were used to determine risk factors for the development of postoperative AL. RESULTS: Of the 577 patients included, 36 (6.2%) had symptomatic AL. The optimal cutoff value of the NLR for predicting AL was 2.66. After propensity score matching, the incidence of AL was significantly greater in the ≥ 2.66 NLR subgroup than in the < 2.66 NLR subgroup (11.5% vs 2.5%; P = 0.012). Univariate logistic regression analysis revealed statistically significant correlations between blood transfusion intraoperatively and within 2 d postoperatively, preoperative albumin concentration, preoperative prognostic nutritional index, and preoperative NLR and AL occurrence (P < 0.05); multivariate logistic regression analysis revealed that an NLR ≥ 2.66 [odds ratio (OR) = 5.51; 95% confidence interval (CI): 1.50-20.26; P = 0.010] and blood transfusion intraoperatively and within 2 d postoperatively (OR = 2.52; 95%CI: 0.88-7.25; P = 0.049) were risk factors for the occurrence of symptomatic AL. CONCLUSION: A preoperative NLR ≥ 2.66 and blood transfusion intraoperatively and within 2 d postoperatively are associated with a higher incidence of postoperative symptomatic AL in elderly patients with colon cancer. The preoperative NLR has predictive value for postoperative symptomatic AL after elective surgery in elderly patients with colon cancer.

5.
Nat Genet ; 56(3): 442-457, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38361033

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is a complex disease with remarkable immune and metabolic heterogeneity. Here we perform genomic, transcriptomic, proteomic, metabolomic and spatial transcriptomic and metabolomic analyses on 100 patients with ccRCC from the Tongji Hospital RCC (TJ-RCC) cohort. Our analysis identifies four ccRCC subtypes including De-clear cell differentiated (DCCD)-ccRCC, a subtype with distinctive metabolic features. DCCD cancer cells are characterized by fewer lipid droplets, reduced metabolic activity, enhanced nutrient uptake capability and a high proliferation rate, leading to poor prognosis. Using single-cell and spatial trajectory analysis, we demonstrate that DCCD is a common mode of ccRCC progression. Even among stage I patients, DCCD is associated with worse outcomes and higher recurrence rate, suggesting that it cannot be cured by nephrectomy alone. Our study also suggests a treatment strategy based on subtype-specific immune cell infiltration that could guide the clinical management of ccRCC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Neoplasias Renales/genética , Neoplasias Renales/patología , Multiómica , Proteómica , Reprogramación Metabólica , Diciclohexilcarbodiimida , Progresión de la Enfermedad , Pronóstico
6.
J Transl Med ; 22(1): 212, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38419050

RESUMEN

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is known for abnormal lipid metabolism and widespread activation of HIF-2α. Recently, the importance of autophagy in ccRCC has been focused, and it has potential connections with HIF-2α and lipid metabolism. However, the specific regulatory mechanism between HIF-2α, autophagy, and lipid metabolism in ccRCC is still unclear. METHODS: In this study, Bioinformatics Analysis and Sequencing of the whole transcriptome were used to screen our target. The expression of TBC1D5 in renal clear cell carcinoma was confirmed by database analysis, immunohistochemistry, PCR and Western blot. The effects of TBC1D5 on tumor cell growth, migration, invasion and lipid metabolism were examined by CCK8, Transwell and oil red staining, and the mechanism of TBC1D5 on autophagy was investigated by Western blot, fluorescence microscopy and electron microscopy. Chloroquine and rapamycin were used to verified the key role of autophagy in effects of TBC1D5 on tumor cell. The regulatory mechanism of TBC1D5 in renal clear cell carcinoma (RCC) was investigated by shhif-2α, shTBC1D5, mimic, inhibitor, ChIP and Luciferase experiments. The animal model of ccRCC was used to evaluate the biological function of TBC1D5 in vivo. RESULTS: In this study, TBC1D5 was found to be an important bridge between autophagy and HIF-2α. Specifically, TBC1D5 is significantly underexpressed in ccRCC, serving as a tumor suppressor which inhibits tumor progression and lipid accumulation, and is negatively regulated by HIF-2α. Further research has found that TBC1D5 regulates the autophagy pathway to reverse the biological function of HIF-2α in ccRCC. Mechanism studies have shown that HIF-2α regulates TBC1D5 through hsa-miR-7-5p in ccRCC, thereby affecting tumor progression and lipid metabolism through autophagy. CONCLUSIONS: Our research reveals a completely new pathway, HIF-2α/hsa-miR-7-5p/TBC1D5 pathway affects ccRCC progression and lipid metabolism by regulating autophagy.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Animales , Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Metabolismo de los Lípidos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica
7.
Environ Manage ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38376512

RESUMEN

Pb soil pollution poses a serious health risk to both the environment and humans. Immobilization is the most common strategy for remediation of heavy metal polluted soil. In this study, municipal sewage sludge was used as an amendment for rehabilitation of Pb-contaminated soils, for agricultural use, near a lead-acid battery factory. The passivation effect was further improved by the addition of phosphate fertilizer. It was found that the leachable Pb content in soils was decreased from 49.6 mg kg-1 to 16.1-36.6 mg kg-1 after remediation of sludge for 45 d at applied dosage of municipal sewage sludge of 4-16 wt%, and further decreased to 14.3-34.3 mg kg-1 upon extension of the remediation period to 180 d. The addition of phosphate fertilizer greatly enhanced the Pb immobilization, with leachable Pb content decreased to 2.0-23.6 mg kg-1 with increasing dosage of phosphate fertilizer in range of 0.8-16 wt% after 180 d remediation. Plant assays showed that the bioavailability of Pb was significantly reduced by the soil remediation, with the content of absorbed Pb in mung bean roots decreased by as much as 87.0%. The decrease in mobility and biotoxicity of the soil Pb is mainly attributed to the speciation transformation of carbonate, Fe-Mn oxides and organic matter bound Pb to residue Pb under the synergism of reduction effect of sludge and acid dissolution and precipitation effect of phosphate fertilizer. This study suggests a new method for remediation of Pb-contaminated soil and utilization of municipal sewage sludge resources.

8.
IEEE Trans Pattern Anal Mach Intell ; 46(6): 4188-4205, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38227419

RESUMEN

Existing studies on knowledge distillation typically focus on teacher-centered methods, in which the teacher network is trained according to its own standards before transferring the learned knowledge to a student one. However, due to differences in network structure between the teacher and the student, the knowledge learned by the former may not be desired by the latter. Inspired by human educational wisdom, this paper proposes a Student-Centered Distillation (SCD) method that enables the teacher network to adjust its knowledge transfer according to the student network's needs. We implemented SCD based on various human educational wisdom, e.g., the teacher network identified and learned the knowledge desired by the student network on the validation set, and then transferred it to the latter through the training set. To address the problems of current deficiency knowledge, hard sample learning and knowledge forgetting faced by a student network in the learning process, we introduce and improve Proportional-Integral-Derivative (PID) algorithms from automation fields to make them effective in identifying the current knowledge required by the student network. Furthermore, we propose a curriculum learning-based fuzzy strategy and apply it to the proposed PID control algorithm, such that the student network in SCD can actively pay attention to the learning of challenging samples after with certain knowledge. The overall performance of SCD is verified in multiple tasks by comparing it with state-of-the-art ones. Experimental results show that our student-centered distillation method outperforms existing teacher-centered ones.


Asunto(s)
Algoritmos , Estudiantes , Humanos , Aprendizaje Automático , Lógica Difusa , Conocimiento
9.
Chem Commun (Camb) ; 60(16): 2176-2179, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38289337

RESUMEN

d-π overlap, which represents overlap between metal-d and graphene-π orbitals to facilitate electron transfer, has rarely been reported. Ni/PtNi-G2 exhibits exceptional performance in seawater hydrogen evolution due to the electron-rich surface on Pt resulting from enhanced d-π overlap and subsequent electron transfer from graphene and Ni to Pt.

10.
Eur J Cardiothorac Surg ; 64(6)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37975876

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the performance of consolidation-to-tumour ratio (CTR) and the radiomic models in two- and three-dimensional modalities for assessing radiological invasiveness in early-stage lung adenocarcinoma. METHODS: A retrospective analysis was conducted on patients with early-stage lung adenocarcinoma from Guangdong Provincial People's Hospital and Shenzhen People's Hospital. Manual delineation of pulmonary nodules along the boundary was performed on cross-sectional images to extract radiomic features. Clinicopathological characteristics and radiomic signatures were identified in both cohorts. CTR and radiomic score for every patient were calculated. The performance of CTR and radiomic models were tested and validated in the respective cohorts. RESULTS: A total of 818 patients from Guangdong Provincial People's Hospital were included in the primary cohort, while 474 patients from Shenzhen People's Hospital constituted an independent validation cohort. Both CTR and radiomic score were identified as independent factors for predicting pathological invasiveness. CTR in two- and three-dimensional modalities exhibited comparable results with areas under the receiver operating characteristic curves and were demonstrated in the validation cohort (area under the curve: 0.807 vs 0.826, P = 0.059) Furthermore, both CTR in two- and three-dimensional modalities was able to stratify patients with significant relapse-free survival (P < 0.000 vs P < 0.000) and overall survival (P = 0.003 vs P = 0.001). The radiomic models in two- and three-dimensional modalities demonstrated favourable discrimination and calibration in independent cohorts (P = 0.189). CONCLUSIONS: Three-dimensional measurement provides no additional clinical benefit compared to two-dimensional.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/cirugía , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Recurrencia Local de Neoplasia , Adenocarcinoma del Pulmón/patología
11.
J Orthop Surg Res ; 18(1): 740, 2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37775789

RESUMEN

BACKGROUND: Aging and diabetes can impair the balance function of the elderly and diabetic patients and increase their fall risk. This study aimed to assess the shaking amplitude of the center-of-pressure (CoP) during static standing, to analyze the effects of aging and diabetes on the balance control. MATERIALS AND METHODS: This cross-sectional observational study, compared the balance performance of 20 healthy younger adults (27.65 ± 5.60 years), 16 healthy older adults (58.88 ± 3.54 years) and 15 diabetic patients (58.33 ± 5.33 years) in four static standing conditions on a force plate: horizontal, anteroposterior (AP), left and right slope planes (5° angles on AP, left and right directions, respectively). The trajectory coordinates of the CoP over time were recorded and analyzed by principal components analysis to obtain the 95% confidence ellipse and its parameters: angle, major and minor axes lengths, and area. The balance indicators were compared among the three groups using one-way analysis of variance (ANOVA), Brown-Forsythe test or Kruskal-Wallis H test, depending on the normality and homogeneity of variance assumptions. RESULTS: The diabetic group had a significantly larger confidence ellipse area than the healthy younger adults on the horizontal plane (P = 0.032) and than the healthy older adults on the horizontal (P = 0.036), AP slope (P = 0.023), and right ML slope (P = 0.037) planes. There were no significant differences in the major axis length of the confidence ellipse among the three groups. The diabetic group had a significantly longer minor axis length than the healthy younger adults on the AP slope (P = 0.039), left ML slope (P = 0.045) and right ML slope (P = 0.016) planes and than the healthy older adults on the AP slope (P = 0.007), left ML slope (P = 0.035) and right ML slope (P = 0.012) planes. CONCLUSIONS: The balance control of diabetic patients is decreased compared with healthy younger and older people, and the body swing amplitude increases mainly in the direction of minor axis of confidence ellipse during static standing, while the swing amplitude in the direction of the major axis has no significant change. Evaluating the balance function of diabetic patients can help clinicians identify people with fall risk early and intervene early, thereby reducing the occurrence of fall events in this population.


Asunto(s)
Diabetes Mellitus , Equilibrio Postural , Humanos , Anciano , Análisis de Componente Principal , Estudios Transversales , Envejecimiento
12.
Elife ; 122023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37751231

RESUMEN

The hippocampus executes crucial functions from declarative memory to adaptive behaviors associated with cognition and emotion. However, the mechanisms of how morphogenesis and functions along the hippocampal dorsoventral axis are differentiated and integrated are still largely unclear. Here, we show that Nr2f1 and Nr2f2 genes are distinctively expressed in the dorsal and ventral hippocampus, respectively. The loss of Nr2f2 results in ectopic CA1/CA3 domains in the ventral hippocampus. The deficiency of Nr2f1 leads to the failed specification of dorsal CA1, among which there are place cells. The deletion of both Nr2f genes causes almost agenesis of the hippocampus with abnormalities of trisynaptic circuit and adult neurogenesis. Moreover, Nr2f1/2 may cooperate to guarantee appropriate morphogenesis and function of the hippocampus by regulating the Lhx5-Lhx2 axis. Our findings revealed a novel mechanism that Nr2f1 and Nr2f2 converge to govern the differentiation and integration of distinct characteristics of the hippocampus in mice.


Asunto(s)
Hipocampo , Neurogénesis , Ratones , Animales , Hipocampo/fisiología , Neurogénesis/genética , Receptores Citoplasmáticos y Nucleares/genética
13.
Orthop Surg ; 15(11): 2777-2785, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37749776

RESUMEN

BACKGROUND: Different treatment methods have been developed for acute Achilles tendon rupture (ATR), including conservative treatment, minimally invasive or transdermal surgery, and open surgery, and there is no consensus about which method is superior. It is important to clarify the presence of Achilles tendon (AT) degeneration, the rupture site, and the rupture shape before surgery to determine whether minimally invasive or open surgery should be selected, thereby reducing the re-rupture rate following acute ATR. The aim of this study was to investigate the diagnostic value of MRI in identifying the presence of AT degeneration, the rupture site, and the rupture shape for acute closed ATR. METHODS: From January 2016 to December 2019, patients with acute closed ATR who had undergone repair surgery were retrospectively enrolled. All patients received MRI examination, and the distance between the insertion site and broken end and the rupture shape (types I, II, and III) were independently determined by two observers. Then, the stump of the AT was exposed during the operation. The rupture site and rupture shape were recorded and compared and analyzed with the MRI results. Consistency analyses (using Cohen's kappa coefficient or intraclass correlation coefficient-ICC) and calculation of diagnostic performance indexes were, respectively, conducted to evaluate the diagnostic value of the MRI. RESULTS: This study included 47 consecutive patients with acute ATR, with an average age of 38.4 years. Among them, 40 were male, and seven were female. The intraoperative exploration demonstrated a total of 34 (72.3%), 10 (21.3%), and three (6.4%) patients with type I, II, and III ruptures, respectively. The average distance between the insertion site and the proximal broken end measured intraoperatively was 4.07 ± 1.57 cm. High or excellent consistencies were found for ATR classifications (kappa: 0.739-0.770, p < 0.001) and rupture sites (ICC: 0.962-0.979, p < 0.001) between two observers and between observers 1 and 2 and intraoperative findings. Tendinopathy was identified in 22 patients by MRI and confirmed during surgery. CONCLUSIONS: MRI scanning of acute closed ATR can help determine whether there is degeneration of the AT, as well as the location and shape of the rupture, which can guide the selection of the optimal operation method for orthopedic surgeons. Therefore, it is necessary to take preoperative MRI scans for patients with acute Achilles tendon ruptures.


Asunto(s)
Tendón Calcáneo , Procedimientos Ortopédicos , Traumatismos de los Tendones , Humanos , Masculino , Femenino , Adulto , Estudios Retrospectivos , Tendón Calcáneo/diagnóstico por imagen , Tendón Calcáneo/cirugía , Traumatismos de los Tendones/diagnóstico por imagen , Traumatismos de los Tendones/cirugía , Procedimientos Ortopédicos/métodos , Imagen por Resonancia Magnética , Rotura/diagnóstico por imagen , Rotura/cirugía , Enfermedad Aguda , Resultado del Tratamiento
14.
iScience ; 26(9): 107680, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37680468

RESUMEN

Progressive damage of retinal ganglion cells (RGCs) is observed in early diabetic retinopathy. Intracellular Ca2+ overload mediated by Ca2+ influx through voltage-gated Ca2+ channels (VGCCs) is involved in neurodegeneration, whereas glucagon-like peptide-1 (GLP-1) provides neuroprotection. However, whether GLP-1 plays a neuroprotective role in diabetic retinas by modulating VGCCs remains unknown. We found that eye drops of exendin-4, a long-acting GLP-1 receptor (GLP-1R) agonist, prevented the increase of L-type Ca2+ current (ILCa) densities of RGCs induced by 4-week hyperglycemia and promoted RGC survival by suppressing L-type VGCC (L-VGCC) activity in streptozotocin-induced diabetic rats. Moreover, exendin-4-induced suppression of ILCa in RGCs may be mediated by a GLP-1R/Gs/cAMP-PKA/ryanodine/Ca2+/calmodulin/calcineurin/PP1 signaling pathway. Furthermore, exendin-4 functionally improved the light-evoked spiking ability of diabetic RGCs. These results suggest that GLP-1R activation enhances cAMP to PP1 signaling and that PP1 inactivates L-VGCCs by dephosphorylating them, thereby reducing Ca2+ influx, which could protect RGCs against excitotoxic Ca2+ overload.

15.
ACS Appl Mater Interfaces ; 15(34): 40963-40974, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37599413

RESUMEN

High-voltage and high-power devices are indispensable in spacecraft for outer space explorations, whose operations require aerospace materials with adequate vacuum surface insulation performance. Despite persistent attempts to fabricate such materials, current efforts are restricted to trial-and-error methods and a universal design guideline is missing. The present work proposes to improve the vacuum surface insulation by tailoring the surface trap state density and energy level of the metal oxides with varied bandgaps, using coating on a polyimide (PI) substrate, aiming for a more systematical workflow for the insulation material design. First-principle calculations and trap diagnostics are employed to evaluate the material properties and reveal the interplay between trap states and the flashover threshold, supported by dedicated analyses of the flashover voltage, secondary electron emission (SEE) from insulators, and surface charging behaviors. Experimental results suggest that the coated PI (i.e., CuO@PI, SrO@PI, MgO@PI, and Al2O3@PI) can effectively increase the trap density and alter the trap energy levels. Elevated trap density is demonstrated to always yield lower SEE. In addition, increasing shallow trap density accelerates surface charge dissipation, which is favorable for improving surface insulation. CuO@PI exhibits the most remarkable increase in shallow trap density, and accordingly, the highest flashover voltage is 42.5% higher than that of pristine PI. This study reveals the critical role played by surface trap states in flashover mitigation and offers a novel strategy to optimize the surface insulation of materials.

16.
Naunyn Schmiedebergs Arch Pharmacol ; 396(12): 3503-3528, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37535076

RESUMEN

Mitochondria serve as a vital energy source for nerve cells. The mitochondrial network also acts as a defense mechanism against external stressors that can threaten the stability of the nervous system. However, excessive accumulation of damaged mitochondria can lead to neuronal death. Mitophagy is an essential pathway in the mitochondrial quality control system and can protect neurons by selectively removing damaged mitochondria. In most neurological disorders, dysfunctional mitochondria are a common feature, and drugs that target mitophagy can improve symptoms. Here, we reviewed the role of mitophagy in Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's disease, stroke, and traumatic brain injuries. We also summarized drug and non-drug approaches to promote mitophagy and described their therapeutic role in neurological disorders in order to provide valuable insight into the potential therapeutic agents available for neurological disease treatment. However, most studies on mitophagy regulation are based on preclinical research using cell and animal models, which may not accurately reflect the effects in humans. This poses a challenge to the clinical application of drugs targeting mitophagy. Additionally, these drugs may carry the risk of intolerable side effects and toxicity. Future research should focus on the development of safer and more targeted drugs for mitophagy.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Parkinson , Animales , Humanos , Mitofagia/fisiología , Mitocondrias/metabolismo , Enfermedad de Parkinson/metabolismo , Enfermedad de Alzheimer/metabolismo
17.
Nat Med ; 29(7): 1793-1803, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37414900

RESUMEN

Identification of individuals at highest risk of coronary artery disease (CAD)-ideally before onset-remains an important public health need. Prior studies have developed genome-wide polygenic scores to enable risk stratification, reflecting the substantial inherited component to CAD risk. Here we develop a new and significantly improved polygenic score for CAD, termed GPSMult, that incorporates genome-wide association data across five ancestries for CAD (>269,000 cases and >1,178,000 controls) and ten CAD risk factors. GPSMult strongly associated with prevalent CAD (odds ratio per standard deviation 2.14, 95% confidence interval 2.10-2.19, P < 0.001) in UK Biobank participants of European ancestry, identifying 20.0% of the population with 3-fold increased risk and conversely 13.9% with 3-fold decreased risk as compared with those in the middle quintile. GPSMult was also associated with incident CAD events (hazard ratio per standard deviation 1.73, 95% confidence interval 1.70-1.76, P < 0.001), identifying 3% of healthy individuals with risk of future CAD events equivalent to those with existing disease and significantly improving risk discrimination and reclassification. Across multiethnic, external validation datasets inclusive of 33,096, 124,467, 16,433 and 16,874 participants of African, European, Hispanic and South Asian ancestry, respectively, GPSMult demonstrated increased strength of associations across all ancestries and outperformed all available previously published CAD polygenic scores. These data contribute a new GPSMult for CAD to the field and provide a generalizable framework for how large-scale integration of genetic association data for CAD and related traits from diverse populations can meaningfully improve polygenic risk prediction.


Asunto(s)
Enfermedad de la Arteria Coronaria , Humanos , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/genética , Estudio de Asociación del Genoma Completo , Predisposición Genética a la Enfermedad/genética , Factores de Riesgo , Fenotipo
18.
Int J Biol Macromol ; 246: 125633, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37406903

RESUMEN

Poplar is an important tree species for ecological protection, wood production, bioenergy and urban greening; it has been widely planted worldwide. However, the catkin fibers produced by female poplars can cause environmental pollution and safety hazards during spring. This study focused on Populus tomentosa, and revealed the sucrose metabolism regulatory mechanism of catkin fibers development from morphological, physiological and molecular aspects. Paraffin section suggested that poplar catkin fibers were not seed hairs and produced from the epidermal cells of funicle and placenta. Sucrose degradation via invertase and sucrose synthase played the dominant role during poplar catkin fibers development. The expression patterns revealed that sucrose metabolism-related genes played important roles during catkin fibers development. Y1H analysis indicated that there was a potential interaction between sucrose synthase 2 (PtoSUS2)/vacuolar invertase 3 (PtoVIN3) and trichome-regulating MYB transcription factors in poplar. Finally, the two key genes, PtoSUS2 and PtoVIN3, had roles in Arabidopsis trichome density, indicating that sucrose metabolism is important in poplar catkin fibers development. This study is not only helpful for clarifying the mechanism of sucrose regulation during trichome development in perennial woody plants, but also establishes a foundation to solve poplar catkin fibers pollution through genetic engineering methods.

19.
Int J Bioprint ; 9(5): 760, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37457931

RESUMEN

The application of three-dimensional (3D) bioprinting has increased in the biomedical field. The lack of bioinks with both biocompatibility and printability is still a problem to be solved. Silk fibroin materials have good biocompatibility and have a broad application prospect in the field of biomedical materials. At present, most research usually involves Bombyx mori silk fibroin (BSF). However, BSF has low cell adhesion. Compared with BSF, Antheraea pernyi silk fibroin (ASF) isolated from typical non-mulberry silk exhibits a unique arginine-glycine-aspartate (RGD) sequence with good cell adhesion enhancement. In this study, we developed a bioink based on ASF for digital light processing (DLP) 3D bioprinting. The ASF-based bioinks (ASF-MA) were produced by a methacryloylation process using methacrylic anhydride (MA) to achieve the properties of photopolymerization reaction. The ASF-MA hydrogel has mechanical properties, biocompatibility, and especially cell adhesion. Meanwhile, we found that the ASF-MA hydrogels promoted the adhesion, migration, and proliferation of S16 cells. Hence, the ASF-MA hydrogels had the potential applications in biomedical fields.

20.
J Agric Food Chem ; 71(19): 7239-7249, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37158241

RESUMEN

The specific conation of our research is to invent a series of indole derivatives containing a 4,5-dihydro-1H-pyrazoline motif with effective antiviral activity. The anti-potato virus Y (PVY) activities of target compounds were systematically investigated. Most target compounds exhibited good PVY activities. Compound D40, which exhibited outstanding anti-PVY activities, was sieved using a three-dimensional quantitative structure-activity relationship. Based on the anti-PVY activity assessments, the curative and protective activities of D40 were found to be 64.9 and 60.8%, respectively, which were superior to those of the commercial drug Ningnanmycin (50.2 and 50.7%, respectively). In addition, defensive enzyme activities and proteomics results indicate that D40 can increase the three crucial defense-related enzyme activities and regulate the carbon fixation pathway in photosynthetic organisms to intensify the resistance of plants to PVY. Therefore, our study suggests that compound D40 might be used as a suitable crop protection pesticide.


Asunto(s)
Potyvirus , Virus del Mosaico del Tabaco , Antivirales/química , Indoles/farmacología , Indoles/química , Diseño de Fármacos , Relación Estructura-Actividad Cuantitativa , Enfermedades de las Plantas/prevención & control
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