Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Plant Cell Environ ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884345

RESUMO

Proanthocyanidins (PAs) are important metabolites that enhance freezing tolerance of plants. Actinidia arguta, especially freezing-tolerant germplasms, accumulate abundant PAs in dormant shoots and thereby enhance freezing tolerance, but the underlying mechanism is unknown. In this study, we used two A. arguta with contrasting cold-resistant phenotypes, KL and RB, to explore the mechanisms in response to cold tolerance. We determined that a leucoanthocyanidin reductase gene (AaLAR1) was more highly expressed in freezing-tolerant KL than in freezing-sensitive RB. Moreover, overexpressing AaLAR1 in kiwifruit promoted PAs biosynthesis and enhanced cold tolerance. The AaLAR1 promoters of various A. arguta germplasms differ due to the presence of a 60-bp deletion in cold-tolerant genotypes that forms a functional binding site for MYC-type transcription factor. Yeast one-hybrid and two-hybrid, dual-luciferase reporter, bimolecular fluorescence complementation and coimmunoprecipitation assays indicated that the AaMYC2a binds to the MYC-core cis-element in the AaLAR1 promoter with the assistance of AaMYB5a, thereby promoting PAs accumulation in the shoots of cold-tolerant kiwifruit. We conclude that the variation in the AaLAR1 promoter and the AaMYC2a-AaMYB5a-AaLAR1 module shape freezing tolerance in A. arguta. The identification of a key structural variation in the AaLAR1 promoter offers a new target for resistance breeding of kiwifruit.

2.
Animal Model Exp Med ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372410

RESUMO

BACKGROUND: Calcific aortic valve stenosis (CAVS) is one of the most challenging heart diseases in clinical with rapidly increasing prevalence. However, study of the mechanism and treatment of CAVS is hampered by the lack of suitable, robust and efficient models that develop hemodynamically significant stenosis and typical calcium deposition. Here, we aim to establish a mouse model to mimic the development and features of CAVS. METHODS: The model was established via aortic valve wire injury (AVWI) combined with vitamin D subcutaneous injected in wild type C57/BL6 mice. Serial transthoracic echocardiography was applied to evaluate aortic jet peak velocity and mean gradient. Histopathological specimens were collected and examined in respect of valve thickening, calcium deposition, collagen accumulation, osteogenic differentiation and inflammation. RESULTS: Serial transthoracic echocardiography revealed that aortic jet peak velocity and mean gradient increased from 7 days post model establishment in a time dependent manner and tended to be stable at 28 days. Compared with the sham group, simple AVWI or the vitamin D group, the hybrid model group showed typical pathological features of CAVS, including hemodynamic alterations, increased aortic valve thickening, calcium deposition, collagen accumulation at 28 days. In addition, osteogenic differentiation, fibrosis and inflammation, which play critical roles in the development of CAVS, were observed in the hybrid model. CONCLUSIONS: We established a novel mouse model of CAVS that could be induced efficiently, robustly and economically, and without genetic intervention. It provides a fast track to explore the underlying mechanisms of CAVS and to identify more effective pharmacological targets.

3.
Bioact Mater ; 35: 447-460, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38390527

RESUMO

Atherosclerosis is featured as chronic low-grade inflammation in the arteries, which leads to the formation of plaques rich in lipids. M2 macrophage-derived extracellular vesicles (M2EV) have significant potential for anti-atherosclerotic therapy. However, their therapeutic effectiveness has been hindered by their limited targeting capability in vivo. The objective of this study was to create the P-M2EV (platelet membrane-modified M2EV) using the membrane fusion technique in order to imitate the interaction between platelets and macrophages. P-M2EV exhibited excellent physicochemical properties, and microRNA (miRNA)-sequencing revealed that the extrusion process had no detrimental effects on miRNAs carried by the nanocarriers. Remarkably, miR-99a-5p was identified as the miRNA with the highest expression level, which targeted the mRNA of Homeobox A1 (HOXA1) and effectively suppressed the formation of foam cells in vitro. In an atherosclerotic low-density lipoprotein receptor-deficient (Ldlr-/-) mouse model, the intravenous injection of P-M2EV showed enhanced targeting and greater infiltration into atherosclerotic plaques compared to regular extracellular vesicles. Crucially, P-M2EV successfully suppressed the progression of atherosclerosis without causing systemic toxicity. The findings demonstrated a biomimetic platelet-mimic system that holds great promise for the treatment of atherosclerosis in clinical settings.

4.
Nat Commun ; 15(1): 557, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38228638

RESUMO

Calcific aortic valve disease is a prevalent cardiovascular disease with no available drugs capable of effectively preventing its progression. Hence, an efficient drug delivery system could serve as a valuable tool in drug screening and potentially enhance therapeutic efficacy. However, due to the rapid blood flow rate associated with aortic valve stenosis and the lack of specific markers, achieving targeted drug delivery for calcific aortic valve disease has proved to be challenging. Here we find that protease-activated-receptor 2 (PAR2) expression is up-regulated on the plasma membrane of osteogenically differentiated valvular interstitial cells. Accordingly, we develop a magnetic nanocarrier functionalized with PAR2-targeting hexapeptide for dual-active targeting drug delivery. We show that the nanocarriers effectively deliver XCT790-an anti-calcification drug-to the calcified aortic valve under extra magnetic field navigation. We demonstrate that the nano-cargoes consequently inhibit the osteogenic differentiation of valvular interstitial cells, and alleviate aortic valve calcification and stenosis in a high-fat diet-fed low-density lipoprotein receptor-deficient (Ldlr-/-) mouse model. This work combining PAR2- and magnetic-targeting presents an effective targeted drug delivery system for treating calcific aortic valve disease in a murine model, promising future clinical translation.


Assuntos
Estenose da Valva Aórtica , Calcinose , Camundongos , Animais , Valva Aórtica/metabolismo , Estenose da Valva Aórtica/tratamento farmacológico , Osteogênese , Calcinose/tratamento farmacológico , Calcinose/metabolismo , Células Cultivadas , Fenômenos Magnéticos
5.
J Sci Food Agric ; 104(6): 3719-3728, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38160249

RESUMO

BACKGROUND: Skeletal muscle is a major insulin-sensitive tissue with a pivotal role in modulating glucose homeostasis. This study aimed to investigate the effect of resveratrol (RES) intervention during the suckling period on skeletal muscle growth and insulin sensitivity of neonates with intrauterine growth retardation (IUGR) in a pig model. RESULTS: Twelve pairs of normal birth weight (NBW) and IUGR neonatal male piglets were selected. The NBW and IUGR piglets were fed basal formula milk diet or identical diet supplemented with 0.1% RES from 7 to 21 days of age. Myofiber growth and differentiation, inflammation and insulin sensitivity in skeletal muscle were assessed. Early RES intervention promoted myofiber growth and maturity in IUGR piglets by ameliorating the myogenesis process and increasing thyroid hormone level. Administering RES also reduced triglyceride concentration in skeletal muscle of IUGR piglets, along with decreased inflammatory response, increased plasma fibroblast growth factor 21 (FGF21) concentration and improved insulin signaling. Meanwhile, the improvement of insulin sensitivity by RES may be partly regulated by activation of the FGF21/AMP-activated protein kinase α/sirtuin 1/peroxisome proliferator activated receptor-γ coactivator-1α pathway. CONCLUSION: Our results suggest that RES has beneficial effects in promoting myofiber growth and maturity and increasing skeletal muscle insulin sensitivity in IUGR piglets, which open a novel field of application of RES in IUGR infants for improving postnatal metabolic adaptation. © 2023 Society of Chemical Industry.


Assuntos
Fatores de Crescimento de Fibroblastos , Resistência à Insulina , Feminino , Suínos , Animais , Masculino , Humanos , Resveratrol/farmacologia , Resveratrol/metabolismo , Fígado/metabolismo , Retardo do Crescimento Fetal/tratamento farmacológico , Retardo do Crescimento Fetal/veterinária , Retardo do Crescimento Fetal/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Músculo Esquelético/metabolismo , Insulina/metabolismo , Desenvolvimento Muscular
6.
Int J Mol Sci ; 24(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38139080

RESUMO

Brassinosteroids (BRs) play pivotal roles in improving plant stress tolerance. To investigate the mechanism of BR regulation of salt tolerance in kiwifruit, we used 'Hongyang' kiwifruit as the test material. We exposed the plants to 150 mmol/L NaCl stress and irrigated them with exogenous BR (2,4-epibrassinolide). The phenotypic analysis showed that salt stress significantly inhibited photosynthesis in kiwifruit, leading to a significant increase in the H2O2 content of leaves and roots and a significant increase in Na+/K+, resulting in oxidative damage and an ion imbalance. BR treatment resulted in enhanced photosynthesis, reduced H2O2 content, and reduced Na+/K+ in leaves, alleviating the salt stress injury. Furthermore, transcriptome enrichment analysis showed that the differentially expressed genes (DEGs) related to BR treatment are involved in pathways such as starch and sucrose metabolism, pentose and glucuronate interconversions, and plant hormone signal transduction, among others. Among the DEGs involved in plant hormone signal transduction, those with the highest expression were involved in abscisic acid signal transduction. Moreover, there was a significant increase in the expression of the AcHKT1 gene, which regulates ion transduction, and the antioxidant enzyme AcFSD2 gene, which is a key gene for improving salt tolerance. The data suggest that BRs can improve salt tolerance by regulating ion homeostasis and reducing oxidative stress.


Assuntos
Brassinosteroides , Reguladores de Crescimento de Plantas , Brassinosteroides/farmacologia , Brassinosteroides/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Peróxido de Hidrogênio/metabolismo , Perfilação da Expressão Gênica , Estresse Salino , Transcriptoma , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico
7.
ACS Nano ; 17(13): 12072-12086, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37363813

RESUMO

Tissue engineering raised a high requirement to control cell distribution in defined materials and structures. In "ink"-based bioprintings, such as 3D printing and photolithography, cells were associated with inks for spatial orientation; the conditions suitable for one ink are hard to apply on other inks, which increases the obstacle in their universalization. The Magneto-Archimedes effect based (Mag-Arch) strategy can modulate cell locomotion directly without impelling inks. In a paramagnetic medium, cells were repelled from high magnetic strength zones due to their innate diamagnetism, which is independent of substrate properties. However, Mag-Arch has not been developed into a powerful bioprinting strategy as its precision, complexity, and throughput are limited by magnetic field distribution. By controlling the paramagnetic reagent concentration in the medium and the gaps between magnets, which decide the cell repelling scope of magnets, we created simultaneously more than a hundred micrometer scale identical assemblies into designed patterns (such as alphabets) with single/multiple cell types. Cell patterning models for cell migration and immune cell adhesion studies were conveniently created by Mag-Arch. As a proof of concept, we patterned a tumor/endothelial coculture model within a covered microfluidic channel to mimic epithelial-mesenchymal transition (EMT) under shear stress in a cancer pathological environment, which gave a potential solution to pattern multiple cell types in a confined space without any premodification. Overall, our Mag-Arch patterning presents an alternative strategy for the biofabrication and biohybrid assembly of cells with biomaterials featured in controlled distribution and organization, which can be broadly employed in tissue engineering, regenerative medicine, and cell biology research.


Assuntos
Técnicas de Cultura de Células , Tinta , Engenharia Tecidual/métodos , Comunicação Celular , Técnicas Analíticas Microfluídicas , Técnicas de Cocultura , Movimento Celular , Magnetismo , Humanos , Técnicas de Cultura de Células/métodos
8.
Ther Adv Chronic Dis ; 14: 20406223231168755, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152348

RESUMO

Heart failure is typically caused by different cardiovascular conditions and has a poor prognosis. Despite the advances in treatment in recent decades, heart failure has remained a major cause of morbidity and mortality worldwide. As revealed by in vivo and in vitro experiments, inflammation plays a crucial role in adverse cardiac remodeling, ultimately leading to heart failure. Macrophages are central to the innate immune system, and they are the most indispensable cell type for all cardiac injuries and remodeling stages. The immediate microenvironment regulates their polarization and secretion. In this review, we summarize the phenotypic heterogeneity and governing roles of macrophages in the infarcted, inflamed, and aging heart and assess their significance as potential therapeutic targets in heart failure. We also highlight the current missing links and major challenges in the field that remain to be addressed before macrophages can be exploited for therapeutic applications.

9.
Cardiovasc Res ; 119(11): 2117-2129, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37183487

RESUMO

AIMS: The incidence of calcific aortic valve disease (CAVD) has risen over the last decade and is expected to continue rising; however, pharmacological approaches have proven ineffective. In this study, we evaluated the role and underlying mechanisms of human antigen R (HuR)-mediated post-transcriptional regulation in CAVD. METHODS AND RESULTS: We found that HuR was significantly upregulated in human calcified aortic valves and primary aortic valvular interstitial cells (VICs) following osteogenic stimulation. Subsequent functional studies revealed that HuR silencing ameliorated calcification both in vitro and in vivo. For the first time, we demonstrated that HuR directly interacted with the transcript of phosphatidylinositol-5-phosphate 4-kinase, type II, alpha (PIP4K2A), which mediates phosphatidylinositol signalling, facilitates autophagy, and acts as an mRNA stabilizer. HuR positively modulated PIP4K2A expression at the post-transcriptional level and consequently influenced the AKT/mTOR/ATG13 pathway to regulate autophagy and CAVD progression. CONCLUSION: Our study provides new insights into the post-transcriptional regulatory role of HuR in modulating autophagy-positive factors to regulate the pathogenesis of CAVD. Our findings highlight the potential of HuR as an innovative therapeutic target in CAVD treatment.


Assuntos
Antígenos , Estenose da Valva Aórtica , Calcinose , Processamento Pós-Transcricional do RNA , Animais , Feminino , Humanos , Masculino , Camundongos , Antígenos/fisiologia , Antígenos/uso terapêutico , Valva Aórtica/patologia , Estenose da Valva Aórtica/genética , Estenose da Valva Aórtica/metabolismo , Calcinose/genética , Calcinose/metabolismo , Células Cultivadas , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Processamento Pós-Transcricional do RNA/fisiologia , RNA Mensageiro/metabolismo
10.
Arterioscler Thromb Vasc Biol ; 43(4): 504-518, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36756881

RESUMO

BACKGROUND: Angiogenesis is a promising strategy for those with peripheral artery disease. Macrophage-centered inflammation is intended to govern the deficiency of the angiogenic response after hindlimb ischemia. However, little is known about the mechanism of macrophage activation beyond signals from cytokines and chemokines. We sought to identify a novel mechanical signal from the ischemic microenvironment that provokes macrophages and the subsequent inflammatory cascade and to investigate the potential role of Piezo-type mechanosensitive ion channels (Piezo) on macrophages during this process. METHODS: Myeloid cell-specific Piezo1 (Piezo-type mechanosensitive ion channel component 1) knockout (Piezo1ΔMΦ) mice were generated by crossing Piezo1fl/fl (LysM-Cre-/-; Piezo1 flox/flox) mice with LysM-Cre transgenic mice to assess the roles of Piezo1 in macrophages after hindlimb ischemia. Furthermore, in vitro studies were carried out in bone marrow-derived macrophages to decipher the underlying mechanism. RESULTS: We found that tissue stiffness gradually increased after hindlimb ischemia, as indicated by Young's modulus. Compared to Piezo2, Piezo1 expression and activation were markedly upregulated in macrophages from ischemic tissues in concurrence with increased tissue stiffness. Piezo1ΔMΦ mice exhibited improved perfusion recovery by enhancing angiogenesis. Matrigel tube formation assays revealed that Piezo1 deletion promoted angiogenesis by enhancing FGF2 (fibroblast growth factor-2) paracrine signaling in macrophages. Conversely, activation of Piezo1 by increased stiffness or the agonist Yoda1 led to reduced FGF2 production in bone marrow-derived macrophages, which could be blocked by Piezo1 silencing. Mechanistically, Piezo1 mediated extracellular Ca2+ influx and activated Ca2+-dependent CaMKII (calcium/calmodulin-dependent protein kinase II)/ETS1 (ETS proto-oncogene 1) signaling, leading to transcriptional inactivation of FGF2. CONCLUSIONS: This study uncovers a crucial role of microenvironmental stiffness in exacerbating the macrophage-dependent deficient angiogenic response. Deletion of macrophage Piezo1 promotes perfusion recovery after hindlimb ischemia through CaMKII/ETS1-mediated transcriptional activation of FGF2. This provides a promising therapeutic strategy to enhance angiogenesis in ischemic diseases.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Fator 2 de Crescimento de Fibroblastos , Animais , Camundongos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Canais Iônicos , Camundongos Transgênicos , Macrófagos/metabolismo , Isquemia , Perfusão , Membro Posterior/irrigação sanguínea
11.
Animals (Basel) ; 14(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38200832

RESUMO

This experiment was conducted in weaned piglets to determine the effects of exogenous protease to low soybean meal (SBM) diets on growth performance, diarrhea rate, nutrient digestibility, and intestinal morphology. Seventy-two Duroc × Landrace × Yorkshire weaned barrows (21-day-old, 5.88 ± 0.95 kg) were randomly divided into four treatments with six replicates in each following a 2 × 2 factorial arrangement of SBM levels (0 to 14 d, 9%, 7.5%; 15 to 42 d, 20%, 18.5%) and protease (0 or 150 mg/kg) for a 42-day trial. Fecal samples were collected on days 11 to 14 and 38 to 42 of the experiment, and serum, intestinal tissue, and chyme samples were taken at the end of the experiments. Adding protease in low SBM diets had a significant increase in ADG (p < 0.05) and a decrease in F/G (p < 0.05). Protease significantly reduced the diarrhea rate (p < 0.05). Low SBM level decreased the apparent total tract digestibility (ATTD) of crude protein (CP) and ash (p < 0.05) but increased the ATTD of dry matter (DM), ash, organic matter (OM), and CP after the addition of protease (p < 0.05). The apparent ileal digestibility (AID) of aspartic acid (Asp), threonine (Thr), serine (Ser), alanine (Ala), lysine (Lys), and total amino acids (AAs) were significantly increased by protease supplementation (p < 0.05). Both the SBM-reduced and protease-added diets lead to lower albumin (ALB), albumin/globulin (A/G), and urea nitrogen (UREA) (p < 0.05), but greater globulin (GLOB) with low SBM diets (p < 0.05). The SBM-reduced and protease-added diets decreased the duodenum pH, respectively (p < 0.05). The protease increased the villus:crypt (V:C) in the duodenum and ileum, and ileal villus length (p < 0.05). In conclusion, the dietary supplementation of 150 mg/kg protease improved the intestinal health and performance of the weaned piglets and reversed the negative effect of a 1.5% SBM reduction in nutrient utilization, intestinal pH, and intestinal morphological parameters of weaned piglets.

12.
Stem Cells Int ; 2022: 3705637, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248256

RESUMO

Background: The poor survival rates of transplanted mesenchymal stem cells (MSCs) in harsh microenvironments impair the efficacy of MSCs transplantation in myocardial infarction (MI). Extrinsic apoptosis pathways play an important role in the apoptosis of transplanted MSCs, and Fas apoptosis inhibitory molecule (FAIM) is involved in regulation of the extrinsic apoptosis pathway. Thus, we aimed to explore whether FAIM augmentation protects MSCs against stress-induced apoptosis and thereby improves the therapeutic efficacy of MSCs. Methods: We ligated the left anterior descending coronary artery (LAD) in the mouse heart to generate an MI model and then injected FAIM-overexpressing MSCs (MSCsFAIM) into the peri-infarction area in vivo. Moreover, FAIM-overexpressing MSCs were challenged with oxygen, serum, and glucose deprivation (OGD) in vitro, which mimicked the harsh microenvironment that occurs in cardiac infarction. Results: FAIM was markedly downregulated under OGD conditions, and FAIM overexpression protected MSCs against OGD-induced apoptosis. MSCsFAIM transplantation improved cell retention, strengthened angiogenesis, and ameliorated heart function. The antiapoptotic effect of FAIM was mediated by cellular-FLICE inhibitory protein (c-FLIP), and FAIM augmentation improved the protein expression of c-FLIP by reducing ubiquitin-proteasome-dependent c-FLIP degradation. Furthermore, FAIM inhibited the activation of JNK, and treatment with the JNK inhibitor SP600125 abrogated the reduction in c-FLIP protein expression caused by FAIM silencing. Conclusions: Overall, these results indicated that FAIM curbed the JNK-mediated, ubiquitination-proteasome-dependent degradation of c-FLIP, thereby improving the survival of transplanted MSCs and enhancing their efficacy in MI. This study may provide a novel approach to strengthen the therapeutic effect of MSC-based therapy.

13.
Artigo em Inglês | MEDLINE | ID: mdl-36078657

RESUMO

Medical errors have been identified as one of the greatest evils in the field of healthcare, causing millions of patient deaths around the globe each year, especially in developing and poor countries. Globally, the social, economic, and personal impact of medical errors leads to a multi-trillion USD loss. Undoubtedly, medical errors are serious public health concerns in modern times, which could be mitigated by taking corrective measures. Different factors contribute to an increase in medical errors, including employees' risk of burnout. Indeed, it was observed that hospital employees are more exposed to burnout situations compared to other fields. In this respect, managing hospital employees through transformational leadership (TL) may reduce the risk of burnout. However, surprisingly, studies on the relationship between TL and burnout are scarce in a healthcare system, indicating the existence of a critical knowledge gap. This study aims to fill this knowledge gap by investigating the role of TL in reducing the risk of burnout among hospital employees. At the same time, this study also tests the mediating effects of resilience and role clarity with the conditional indirect effect of intrinsic motivation in the above-proposed relationship. To test different hypotheses, a hypothetical model was developed for which we collected the data from different hospital employees (n = 398). Structural equation modeling (SEM) was considered for statistical validation of hypotheses confirming that TL significantly reduces burnout. The results further indicated that resilience and role clarity mediate this relationship significantly. Lastly, the conditional indirect effect of intrinsic motivation was also confirmed. Our results provide meaningful insights to the hospital administrators to combat burnout, a critical reason for medical errors in hospitals. Further, by incorporating the TL framework, a hospital may reduce the risk of burnout (and, hence, medical errors); on the one hand, such a leadership style also provides cost benefits (reduced medical errors improve cost efficiency). Other different theoretical and practical contributions are discussed in detail.


Assuntos
Esgotamento Profissional , Liderança , Esgotamento Profissional/prevenção & controle , Hospitais , Humanos , Motivação , Recursos Humanos em Hospital
14.
JACC Basic Transl Sci ; 7(7): 697-712, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35958694

RESUMO

There are currently no pharmacological therapies for calcific aortic valve disease (CAVD). Here, we evaluated the role of protein tyrosine phosphatase 1B (PTP1B) inhibition in CAVD. Up-regulation of PTP1B was critically involved in calcified human aortic valve, and PTP1B inhibition had beneficial effects in preventing fibrocalcific response in valvular interstitial cells and LDLR-/- mice. In addition, we reported a novel function of PTP1B in regulating mitochondrial homeostasis by interacting with the OPA1 isoform transition in valvular interstitial cell osteogenesis. Thus, these findings have identified PTP1B as a potential target for preventing aortic valve calcification in patients with CAVD.

15.
Sensors (Basel) ; 22(16)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36015886

RESUMO

Images captured in a low-light environment are strongly influenced by noise and low contrast, which is detrimental to tasks such as image recognition and object detection. Retinex-based approaches have been continuously explored for low-light enhancement. Nevertheless, Retinex decomposition is a highly ill-posed problem. The estimation of the decomposed components should be combined with proper constraints. Meanwhile, the noise mixed in the low-light image causes unpleasant visual effects. To address these problems, we propose a Constraint Low-Rank Approximation Retinex model (CLAR). In this model, two exponential relative total variation constraints were imposed to ensure that the illumination is piece-wise smooth and that the reflectance component is piece-wise continuous. In addition, the low-rank prior was introduced to suppress the noise in the reflectance component. With a tailored separated alternating direction method of multipliers (ADMM) algorithm, the illumination and reflectance components were updated accurately. Experimental results on several public datasets verify the effectiveness of the proposed model subjectively and objectively.

16.
Artigo em Inglês | MEDLINE | ID: mdl-36011417

RESUMO

This paper examines the impact of environmental uncertainty and environmental regulation on enterprises' green technological innovation, using a panel data of Chinese A-share listed companies in Shanghai and Shenzhen from 2005 to 2019 to conduct an empirical study using an OLS model and Poisson regression model. We employ environmental complexity and environmental dynamism to measure environmental uncertainty, and we have the following findings: first, both environmental uncertainty and environmental regulation promote enterprises' green technological innovation, while environmental regulation has positive moderating effects on the relationship between environmental uncertainty and enterprises' green technological innovation; second, environmental complexity positively affects enterprises' green technological innovation, while environmental dynamism has negative effects on enterprises' green technological innovation; third, environmental regulation accentuates the relationship between environmental complexity and green technological innovation, while it weakens the relationship between environmental dynamism and green technological innovation.


Assuntos
Invenções , China , Incerteza
17.
Int J Mol Sci ; 23(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35887372

RESUMO

Kiwifruit is loved by consumers for its unique taste and rich vitamin C content. Kiwifruit are very sensitive to adverse soil environments owing to fleshy and shallow roots, which limits the uptake of water and nutrients into the root system, resulting in low yield and poor fruit quality. Lateral roots are the key organs for plants to absorb water and nutrients. Improving water and fertilizer use efficiency by promoting lateral root development is a feasible method to improve yield and quality. Expansin proteins plays a major role in lateral root growth; hence, it is important to identify expansin protein family members, screen key genes, and explore gene function in root development. In this study, 41 expansin genes were identified based on the genome of kiwifruit ('Hongyang', Actinidia chinensis). By clustering with the Arabidopsis thaliana expansin protein family, the 41 AcExpansin proteins were divided into four subfamilies. The AcExpansin protein family was further analysed by bioinformatics methods and was shown to be evolutionarily diverse and conserved at the DNA and protein levels. Based on previous transcriptome data and quantitative real-time PCR assays, we screened the candidate gene AcEXPA23. Overexpression of AcEXPA23 in kiwifruit increased the number of kiwifruit lateral roots.


Assuntos
Actinidia , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Água/metabolismo
18.
J Magn Reson ; 339: 107229, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35512441

RESUMO

Two dimensional homonuclear correlation spectra like COSY, TOCSY and NOESY are classic two-dimensional spectra for analyzing coupling networks and delivering structural information of molecules. Two main challenges of the homonuclear correlation spectra are resolution and efficiency. Because of the complexity of the molecular structure and the effect of scalar coupling, spectral resolution is still difficult to meet the demand, and a higher resolution is needed to improve the quality of the homonuclear correlation spectrum. On the other hand, although some homonuclear correlation spectra are often used together (such as COSY and TOCSY), they are generally sampled separately, and as the number of sampling points in the indirect dimension increases, experiment time increases dramatically. Here, we propose a scheme that can be used to simultaneously obtain indirect dimension pure shift COSY and TOCSY or indirect dimension pure shift COSY and NOESY to improve the resolution of them, while reducing the sampling time and improving the efficiency.


Assuntos
Espectroscopia de Ressonância Magnética , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular
19.
Adv Healthc Mater ; 11(8): e2102059, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34969157

RESUMO

Heart valves have extraordinary fatigue resistance which beat ≈3 billion times in a lifetime. Bioprosthetic heart valves (BHVs) made from fixed heteroplasm that are incrementally used in heart valve replacement fail to sustain the expected durability due to thrombosis, poor endothelialization, inflammation, calcification, and especially mechanical damage induced biocompatibility change. No effective strategy has been reported to conserve the biological properties of BHV after long-term fatigue test. Here, a double-network tough hydrogel is introduced, which interpenetrate and anchor into the matrix of decellularized porcine pericardium (dCell-PP) to form robust and stable conformal coatings and reduce immunogenicity. The ionic crosslinked hyaluronic acid (HA) network mimics the glycocalyx on endothelium which improves antithrombosis and accelerates endothelialization; the chemical crosslinked hydrophilic polyacrylamide (PAAm) network further enhances antifouling properties and strengthens the shielding hydrogels and their interaction with dCell-PP. In vitro and rabbit ex vivo shunt assay demonstrate great hemocompatibility of polyacrylamide/HA hydrogel hybrid PP (P/H-PP). Cell experiments and rat subcutaneous implantation confirm satisfactory endothelialization, biocompatibility, and anticalcification properties. For hydrodynamic experiment, P/H-PP gains full mark at different flow conditions and sustains excellent biomechanical and biological properties after 200 000 000 cycles. P/H double-network hydrogel armoring dCell-PP is a promising progress to extend BHV durability for clinical implantation therapy.


Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Animais , Valvas Cardíacas , Hidrogéis/química , Hidrogéis/farmacologia , Pericárdio/química , Coelhos , Ratos , Suínos
20.
FEMS Microbiol Lett ; 368(20)2021 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-34755861

RESUMO

Non-Saccharomyces yeasts are important players during winemaking and may come from grapes grown in vineyards. To study the diversity of non-Saccharomyces yeasts on grape berry surfaces, 433 strains were isolated from different Cabernet Sauvignon vineyards grown in Henan Province. Our results demonstrated that these strains were classified into 16 morphotypes according to their growth morphology on Wallerstein Laboratory agar medium, and were identified as seven species from four genera-Hanseniaspora opuntiae, Hanseniaspora vineae, Hanseniaspora uvarum, Pichia occidentalis, Pichia kluyveri, Issatchenkia terricola and Saturnispora diversa-based on a series of molecular biological experiments. Hanseniaspora opuntiae was obtained from all sampling sites except Changyuan County, while Pichia kluyveri and Saturnispora diversa were only found in sites of Zhengzhou Grape Resource Garden and Minquan County, respectively. The site Minquan was home of the greatest species richness, while only one single species (Hanseniaspora opuntiae) was detected at NAPA winery from Zhengzhou or at Anyang County. Finally, this study suggested that the geographic distribution and diversity of non-Saccharomyces yeast populations on Cabernet Sauvignon grape berries were likely to be determined by a combination of grape varieties and environmental factors.


Assuntos
Biodiversidade , Frutas , Vitis , Leveduras , China , Fazendas , Fermentação , Frutas/microbiologia , Hanseniaspora/classificação , Hanseniaspora/isolamento & purificação , Pichia/classificação , Pichia/isolamento & purificação , Saccharomycetales/classificação , Saccharomycetales/isolamento & purificação , Vitis/microbiologia , Vinho/microbiologia , Leveduras/classificação , Leveduras/isolamento & purificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...