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1.
Adv Mater ; : e2402000, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738693

RESUMO

The disparity between growth substrates and application-specific substrates can be mediated by reliable graphene transfer, the lack of which currently strongly hinders the graphene applications. Conventionally, the removal of soft polymers, that support the graphene during the transfer, would contaminate graphene surface, produce cracks, and leave unprotected graphene surface sensitive to airborne contaminations. In this work, we found that polyacrylonitrile (PAN) can function as polymer medium for transferring wafer-size graphene, and encapsulating layer to deliver high-performance graphene devices. Therefore, PAN, that is compatible with device fabrication, does not need to be removed for subsequent applications. We achieved the crack-free transfer of 4-inch graphene onto SiO2/Si wafers, and the wafer-scale fabrication of graphene-based field-effect transistor (FET) arrays with no observed clear doping, uniformly high carrier mobility (∼11,000 cm2 V-1 s-1) and long-term stability at room temperature. Our work presents new concept for designing the transfer process of two-dimensional (2D) materials, in which multifunctional polymer can be retained, and offers a reliable method for fabricating wafer-scale devices of 2D materials with outstanding performance. This article is protected by copyright. All rights reserved.

2.
Nanoscale ; 16(16): 7862-7873, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38568087

RESUMO

Recent years have witnessed advances in chemical vapor deposition growth of graphene films on metal foils with fine scalability and thickness controllability. However, challenges for obtaining wrinkle-free, defect-free and large-area uniformity remain to be tackled. In addition, the real commercial applications of graphene films still require industrially compatible transfer techniques with reliable performance of transferred graphene, excellent production capacity, and suitable cost. Transferred graphene films, particularly with a large area, still suffer from the presence of transfer-related cracks, wrinkles and contaminants, which would strongly deteriorate the quality and uniformity of transferred graphene films. Potential applications of graphene films include moisture barrier films, transparent conductive films, electromagnetic shielding films, and optical communications; such applications call different requirements for the performance of transferred graphene, which, in turn, determine the suitable transfer techniques. Besides the reliable transfer process, automatic machines should be well developed for the future batch transfer of graphene films, ensuring the repeatability and scalability. This mini-review provides a summary of recent advances in the transfer of graphene films and offers a perspective for future directions of transfer techniques that are compatible for industrial batch transfer.

3.
Cell Mol Biol Lett ; 29(1): 62, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684954

RESUMO

BACKGROUND: Enhancing angiogenesis may be an effective strategy to promote functional recovery after ischemic stroke. Inflammation regulates angiogenesis. Microglia are crucial cells that initiate inflammatory responses after various brain injuries. Long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) plays a role in regulating brain injury. This study aimed to explore the effects of NEAT1-regulated microglial polarization on the neovascularization capacity of cerebrovascular endothelial cells and the underlying molecular regulatory mechanisms. METHODS: Mouse cerebral arterial endothelial cells (mCAECs) were co-cultured with BV-2 cells in different groups using a Transwell system. NEAT1 expression levels were measured by fluorescence quantitative reverse transcription PCR. Levels of IL-1ß, IL-6, TNF-α, Arg-1, IL-4, and IL-10 were determined using ELISA. Expression levels of CD86 and CD163 were detected by immunofluorescence. The neovascularization capacity of mCAECs was assessed using CCK-8, Transwell, Transwell-matrigel, and tube formation assays. Label-free quantification proteomics was carried out to identify differentially expressed proteins. Protein levels were measured by Western blotting. RESULTS: NEAT1 overexpression induced M1 polarization in BV-2 cells, whereas NEAT1 knockdown blocked lipopolysaccharide-induced M1 polarization in microglia. NEAT1-overexpressing BV-2 cells suppressed the angiogenic ability of mCAECs, and NEAT1-knocking BV-2 cells promoted the angiogenic ability of mCAECs under lipopolysaccharide treatment. Label-free quantitative proteomic analysis identified 144 upregulated and 131 downregulated proteins that were induced by NEAT1 overexpression. The AMP-activated protein kinase (AMPK) signaling pathway was enriched in the Kyoto Encyclopedia of Genes and Genomes analysis of the differentially expressed proteins. Further verification showed that NEAT1 inactivated the AMPK signaling pathway. Moreover, the AMPK activator 5-aminoimidazole-4-carboxamide ribonucleotide reversed the effect of NEAT1 on BV-2 polarization and the regulatory effect of NEAT1-overexpressing BV-2 cells on the angiogenic ability of mCAECs. CONCLUSIONS: NEAT1 inhibits the angiogenic activity of mCAECs by inducing M1 polarization of BV-2 cells through the AMPK signaling pathway. This study further clarified the impact and mechanism of NEAT1 on microglia and the angiogenic ability of cerebrovascular endothelial cells.


Assuntos
Proteínas Quinases Ativadas por AMP , Células Endoteliais , Microglia , RNA Longo não Codificante , Transdução de Sinais , Animais , Microglia/metabolismo , Microglia/efeitos dos fármacos , Camundongos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Artérias Cerebrais/metabolismo , Artérias Cerebrais/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/genética , Linhagem Celular , Polaridade Celular/efeitos dos fármacos
4.
Mol Ther ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38553852

RESUMO

Keloids are characterized by fibroblast hyperproliferation and excessive accumulation of extracellular matrix (ECM) and are a major global health care burden among cutaneous diseases. However, the function of long noncoding RNA (lncRNA)-mediated ECM remodeling during the pathogenesis of keloids is still unclear. Herein, we identified a long noncoding transcript, namely, lymphocyte-specific protein 1 pseudogene 5 (LSP1P5), that modulates ECM component deposition in keloids. First, high-throughput transcriptome analysis showed that LSP1P5 was selectively upregulated in keloids and correlated with more severe disease in a clinical keloid cohort. Therapeutically, the attenuation of LSP1P5 significantly decreased the expression of ECM markers (COL1, COL3, and FN1) both in vitro and in vivo. Intriguingly, an antifibrotic gene, CCAAT enhancer binding protein alpha (CEBPA), is a functional downstream candidate of LSP1P5. Mechanistically, LSP1P5 represses CEBPA expression by hijacking Suppressor of Zeste 12 to the promoter of CEBPA, thereby enhancing the polycomb repressive complex 2-mediated H3K27me3 and changing the chromosomal opening status of CEBPA. Taken together, these findings indicate that targeting LSP1P5 abrogates fibrosis in keloids through epigenetic regulation of CEBPA, revealing a novel antifibrotic therapeutic strategy that bridges our current understanding of lncRNA regulation, histone modification and ECM remodeling in keloids.

5.
J Orthop Surg Res ; 19(1): 198, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528538

RESUMO

PURPOSE: This study aimed to evaluate the protective effects of gentiopicroside against lipopolysaccharide-induced chondrocyte inflammation. METHODS: SW 1353 chondrosarcoma cells were stimulated with LPS (5 µg/ml) for 24 h and treated with different concentrations of gentiopicroside (GPS) for 24 h. The toxic effects of GPS on chondrocytes were determined using a CCK-8 assay and EdU staining. Western blotting, qPCR, and immunofluorescence analysis were used to examine the protective effect of GPS against the inflammatory response in chondrocytes induced by lipopolysaccharide (LPS). One-way ANOVA was used to compare the differences between the groups (significance level of 0.05). RESULTS: The CCK-8 results showed that 10, 20 and 40 µM GPS had no significant toxic effects on chondrocytes; GPS effectively reduced the production of IL-1ß and PGE2, reversed LPS-induced extracellular matrix degradation in cartilage by inhibiting the Stat3/Runx2 signaling pathway, and suppressed the hypertrophic transformation of SW 1353 chondrosarcoma cells. CONCLUSION: Our study demonstrated that GPS significantly inhibited the LPS-induced inflammatory response and hypertrophic cellular degeneration in SW 1353 chondrosarcoma cells and is a valuable traditional Chinese medicine for the treatment of knee osteoarthritis.


Assuntos
Condrossarcoma , Glucosídeos Iridoides , Osteoartrite , Humanos , Condrócitos/metabolismo , Lipopolissacarídeos/toxicidade , Osteoartrite/metabolismo , Sincalida/metabolismo , Sincalida/farmacologia , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Hipertrofia , Condrossarcoma/tratamento farmacológico , Interleucina-1beta/metabolismo , NF-kappa B/metabolismo
6.
RSC Adv ; 14(11): 7572-7581, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38440267

RESUMO

The purpose of this study was to design a novel antioxidant and antibacterial film for food packaging using food-grade raw materials. The films were designed and fabricated based on carboxymethyl chitosan and pectin incorporated with procyanidins (PCs) and phycocyanin (Phy) by the tape casting method. The effects of different proportions of PCs and Phy on the properties and functions of the prepared films were studied. The results showed that the thickness of films could range from 55 to 70 µm, with dense network structure and uniform distribution of elements. Compared with C-Film group, the film loaded with PCs and Phy had lower water solubility and swelling rate, and higher tensile strength and elongation at break. FITR and XRD spectra revealed the molecular interaction mechanism among carboxymethyl chitosan, pectin, PCs and Phy, which could effectively endow the films with ultraviolet barrier properties. Moreover, the addition of PCs and Phy could effectively improve the antioxidant capacity and antibacterial effect of films, for example, the free radical scavenging abilities of most films were above 80% when the concentration of PCs was 40 µg mL-1. In view of these functional properties, the prepared film containing PCs and Phy have been successfully used in food packaging, which was proved by the preservation experiment of grapes. This study can provide theoretical and technical guidance for the preparation of biodegradable antibacterial films, and their application in the food packaging field.

7.
Chemosphere ; 352: 141364, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336034

RESUMO

Diverse paths generated by reactive oxygen species (ROS) can mediate contaminant transformation and fate in the soil/aquatic environments. However, the pathways for ROS production upon the oxygenation of redox-active ferrous iron minerals are underappreciated. Ferrihydrite (Fh) can be reduced to produce Fe(II) by Shewanella oneidensis MR-1, a representative strain of dissimilatory iron-reducing bacteria (DIRB). The microbial reaction formed a spent Fh product named mr-Fh that contained Fe(II). Material properties of mr-Fh were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). Magnetite could be observed in all mr-Fh samples produced over 1-day incubation, which might greatly favor the Fe(II) oxygenation process to produce hydroxyl radical (•OH). The maximum amount of dissolved Fe(II) can reach 1.1 mM derived from added 1 g/L Fh together with glucose as a carbon source, much higher than the 0.5 mM generated in the case of the Luria-Bertani carbon source. This may confirm that MR-1 can effectively reduce Fh and produce biogenetic Fe(II). Furthermore, the oxygenation of Fe(II) on the mr-Fh surface can produce abundant ROS, wherein the maximum cumulative •OH content is raised to about 120 µM within 48 h at pH 5, but it is decreased to about 100 µM at pH 7 for the case of MR-1/Fh system after a 7-day incubation. Thus, MR-1-mediated Fh reduction is a critical link to enhance ROS production, and the •OH species is among them the predominant form. XPS analysis proves that a conservable amount of Fe(II) species is subject to adsorption onto mr-Fh. Here, MR-1-mediated ROS production is highly dependent on the redox activity of the form Fe(II), which should be the counterpart presented as the adsorbed Fe(II) on surfaces. Hence, our study provides new insights into understanding the mechanisms that can significantly govern ROS generation in the redox-oscillation environment.


Assuntos
Compostos Férricos , Shewanella , Espécies Reativas de Oxigênio/metabolismo , Compostos Férricos/química , Minerais/química , Ferro/química , Oxirredução , Shewanella/metabolismo , Óxido Ferroso-Férrico/metabolismo , Carbono/metabolismo
8.
PeerJ ; 12: e16915, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38390389

RESUMO

Background: Type 2 diabetes mellitus (T2DM) with chronic kidney disease (CKD) poses a serious health threat and becomes a new challenge. T2DM patients with CKD fall into three categories, diabetic nephropathy (DN), non-diabetic kidney disease (NDKD), and diabetic nephropathy plus non-diabetic kidney disease (DN + NDKD), according to kidney biopsy. The purpose of our study was to compare the clinical characteristics and kidney outcomes of DN, NDKD, and DN + NDKD patients. Methods: Data on clinical characteristics, pathological findings, and prognosis were collected from June 2016 to July 2022 in patients with previously diagnosed T2DM and confirmed DN and or NDKD by kidney biopsy at Tongji Hospital in Wuhan, China. The endpoint was defined as kidney transplantation, dialysis, or a twofold increase in serum creatinine. Results: In our 6-year retrospective cohort research, a total of 268 diabetic patients were admitted and categorized into three groups by kidney biopsy. The 268 patients were assigned to DN (n = 74), NDKD (n = 109), and DN + NDKD (n = 85) groups. The most frequent NDKD was membranous nephropathy (MN) (n = 45,41.28%). Hypertensive nephropathy was the most common subtype in the DN+NDKD group (n = 34,40%). A total of 34 patients (12.7%) reached the endpoint. The difference between the Kaplan-Meier survival curves of the DN, NDKD, and DN + NDKD groups was significant (p < 0.05). Multifactorial analysis showed that increased SBP [HR (95% CI): 1.018(1.002-1.035), p = 0.025], lower Hb [HR(95% CI): 0.979(0.961-0.997), p = 0.023], higher glycosylated hemoglobin [HR(95% CI): 1.338(1.080-1.658), p = 0.008] and reduced serum ALB [HR(95% CI): 0.952(0.910-0.996), p = 0.032] were risk factors for outcomes in the T2DM patients with CKD. Conclusions: This research based on a Chinese cohort demonstrated that the risk of endpoint events differed among DN, NDKD, and DN+NDKD patients. In T2DM patients with CKD, DN patients displayed worse kidney prognosis than those with NDKD or DN + NDKD. Increased SBP, higher glycosylated hemoglobin, lower Hb, and decreased serum ALB may be correlated with adverse kidney outcomes in T2DM patients.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Insuficiência Renal Crônica , Humanos , Nefropatias Diabéticas/terapia , Estudos Retrospectivos , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas , Diálise Renal/efeitos adversos , Insuficiência Renal Crônica/complicações
9.
Front Endocrinol (Lausanne) ; 15: 1323947, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38405141

RESUMO

Introduction: Pineal cysts have long been considered a benign intracranial variation. However, in our clinical practice, it has been observed that some children with central precocious puberty (CPP) who have pineal cysts experience rapid progression in adolescent development. In recent years, there has been a significant increase in the prevalence of CPP in girls, leading to more diagnoses of CPP among children with pineal cysts. Despite this, there is no consensus regarding whether pineal cysts contribute to CPP as one of its organic factors. This study aimed to analyze the clinical characteristics of pineal cysts in children with CPP and explore the potential effects of pineal cysts on puberty development. Methods: This single-center study retrospectively analyzed clinical data from girls aged 3 to 10 years who underwent head/pituitary magnetic resonance imaging at the Children's Hospital Affiliated to Zhengzhou University between 2019 and 2022. The study categorized the detection rates of pineal cysts based on systematic disease classification and compared the rates of cyst detection between girls diagnosed with CPP and those without CPP. Subsequently, CPP-diagnosed girls with pineal cysts were examined. Among CPP-diagnosed girls meeting the study's criteria, those with pineal cysts formed the 'cyst group,' while those without cysts were matched in a 1:1 ratio based on age and body mass index to form the 'non-cyst group.' Comparative analyses were conducted to assess the clinical characteristics between these two groups. CPP-diagnosed girls with cysts were further subdivided into three groups according to cyst size (≤5 mm, 5.1-9.9 mm, and ≥10 mm) to investigate potential differences in clinical characteristics among these subgroups. The study involved an analysis of clinical data from girls diagnosed with CPP and included imaging follow-ups to explore the progression of pineal cysts over time. Results: Among the 23,245 girls who underwent head/pituitary magnetic resonance imaging scans, the detection rate of pineal cysts was 3.6% (837/23,245), with most cases being associated with endocrine diseases. The detection rate of pineal cysts in CPP patients was 6.4% (262/4099), which was significantly higher than the 3.0% (575/19,146) in patients without CPP. In comparison to the non-cyst group, the cyst group exhibited statistically significant increases in estradiol levels, peak luteinizing hormone (LH) levels, peak LH/follicle-stimulating hormone (FSH) ratios, uterine body length, and cervix length (P < 0.001). As cyst size increased, there were significant rises in LH peak, peak LH/FSH ratio, uterine body length, and cervical length (P < 0.01). Estradiol levels and left ovarian volume also showed an increasing trend (P < 0.05). Among girls who underwent follow-up imaging, 26.3% (5/19) exhibited an increase in cyst size. Conclusion: Pineal cysts are relatively common in children with CPP. They may affect the pubertal development process, with larger cysts correlating to faster pubertal development. Therefore, the authors hypothesize that pineal cysts may trigger CPP in some cases, especially when the cysts are larger than 5 mm in size, as indicated by our data.


Assuntos
Cistos do Sistema Nervoso Central , Cistos , Puberdade Precoce , Criança , Feminino , Humanos , Adolescente , Hormônio Luteinizante , Puberdade Precoce/diagnóstico , Estudos Retrospectivos , Hormônio Foliculoestimulante , Cistos/complicações , Cistos/diagnóstico por imagem , Hormônio Foliculoestimulante Humano , Cistos do Sistema Nervoso Central/complicações , Cistos do Sistema Nervoso Central/diagnóstico por imagem , Estradiol
10.
Environ Res ; 249: 118387, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38336162

RESUMO

Achieving a balance between greenhouse gas mitigation and biomass production in grasslands necessitates optimizing irrigation frequency and nitrogen addition, which significantly influence grassland productivity and soil nitrous oxide emissions, and consequently impact the ecosystem carbon dioxide exchange. This study aimed to elucidate these influences using a controlled mesocosm experiment where bermudagrass (Cynodon dactylon L.) was cultivated under varied irrigation frequencies (daily and every 6 days) with (100 kg ha-1) or without nitrogen addition; measurements of net ecosystem carbon dioxide exchange, ecosystem respiration, soil respiration, and nitrous oxide emissions across two cutting events were performed as well. The findings revealed a critical interaction between water-filled pore space, regulated by irrigation, and nitrogen availability, with the latter exerting a more substantial influence on aboveground biomass growth and ecosystem carbon dioxide exchange than water availability. Moreover, the total dry matter was significantly higher with nitrogen addition compared to without nitrogen addition, irrespective of the irrigation frequency. In contrast, soil nitrous oxide emissions were observed to be significantly higher with increased irrigation frequency and nitrogen addition. The effects of nitrogen addition on soil respiration components appeared to depend on water availability, with autotrophic respiration seeing a significant rise with nitrogen addition under limited irrigation (5.4 ± 0.6 µmol m-2 s-1). Interestingly, the lower irrigation frequency did not result in water stress, suggesting resilience in bermudagrass. These findings highlight the importance of considering interactions between irrigation and nitrogen addition to optimize water and nitrogen input in grasslands for a synergistic balance between grassland biomass production and greenhouse gas emission mitigation.


Assuntos
Irrigação Agrícola , Biomassa , Pradaria , Gases de Efeito Estufa , Nitrogênio , Gases de Efeito Estufa/análise , Nitrogênio/metabolismo , Irrigação Agrícola/métodos , Óxido Nitroso/análise , Óxido Nitroso/metabolismo , Solo/química , Cynodon/crescimento & desenvolvimento , Cynodon/metabolismo , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Fertilizantes/análise
11.
Adv Mater ; 36(15): e2308950, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38288661

RESUMO

The real applications of chemical vapor deposition (CVD)-grown graphene films require the reliable techniques for transferring graphene from growth substrates onto application-specific substrates. The transfer approaches that avoid the use of organic solvents, etchants, and strong bases are compatible with industrial batch processing, in which graphene transfer should be conducted by dry exfoliation and lamination. However, all-dry transfer of graphene remains unachievable owing to the difficulty in precisely controlling interfacial adhesion to enable the crack- and contamination-free transfer. Herein, through controllable crosslinking of transfer medium polymer, the adhesion is successfully tuned between the polymer and graphene for all-dry transfer of graphene wafers. Stronger adhesion enables crack-free peeling of the graphene from growth substrates, while reduced adhesion facilitates the exfoliation of polymer from graphene surface leaving an ultraclean surface. This work provides an industrially compatible approach for transferring 2D materials, key for their future applications, and offers a route for tuning the interfacial adhesion that would allow for the transfer-enabled fabrication of van der Waals heterostructures.

12.
Account Res ; : 1-21, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38164053

RESUMO

Despite the increasing prominence of research collaboration, a growing number of studies have confirmed that increasing team size can have limited performance benefits. However, the mechanism of this phenomenon has yet to be established. This study, therefore, quantified responsibility diffusion based on author contribution information and explored its mediating role in the relationship between collaboration size and citation impact (citation count in a four-year window). The results show the following: (1) An inverted U-shaped relationship exists between team size and citation count. (2) Responsibility diffusion plays a partial mediating role between team size and citation count. (3) As team size increases, the degree of responsibility diffusion increases. Lastly, (4) responsibility diffusion has an inverted U-shaped curvilinear relationship with citation count (e.g., a moderate degree of responsibility diffusion has the highest impact). These findings offer a new understanding of the mechanism by which collaboration size influences research performance. This study also has practical implications for solving research collaboration dilemmas based on a group-cognition perspective.

13.
BMC Oral Health ; 24(1): 95, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233785

RESUMO

BACKGROUND: The reconstruction of segmental defect of the mandible has always been a challenge. The customized reconstruction plate without a bone graft is also considered a transitional means of rehabilitation and reconstruction in some cases. METHODS: This study evaluated the biomechanical behaviors of customized plates with different structural designs comparing with commercial plates using the finite element method in reconstrution of the lateral mandible defect. RESULTS: Simulations revealed the stress state in the plate bodies, bone tissues and screws were associated with the width, height, thickness of the plates as well as the distribution of screws. In all of the groups, the system of 16 mm-high, 2.8 mm-thick customized reconstruction plate with 10 screws was considered to be the most ideal design because of the most harmonious biomechanical state. What's more, the stress shielding effects were not obvious in this experiment. Based on the above findings, we conducted a clinical case analysis to verify the mechanical properties of customized reconstruction and obtained a satisfactory operation result. CONCLUSIONS: The results show that by adjusting the contour parameters of the reconstruction plates, an ideal and reliable customized plate can be manufactured. And the customized 3D-printed Ti alloy implant will be a new way to achieve mandibular reconstruction in patients unable to perform autologous bone graft surgery. TRIAL REGISTRATION: The present trial has been registered with ChiCTR, the registration number is ChiCTR 2,000,038,973 on 11/10/2020.


Assuntos
Mandíbula , Titânio , Humanos , Análise de Elementos Finitos , Estresse Mecânico , Mandíbula/cirurgia , Impressão Tridimensional
14.
Biogerontology ; 25(1): 53-69, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37725294

RESUMO

With the increase of population aging, the prevalence of type 2 diabetes (T2D) is also rising. Aging affects the tissues and organs of the whole body, which is the result of various physiological and pathological processes. Adipose tissue has a high degree of plasticity and changes with aging. Aging changes the distribution of adipose tissue, affects adipogenesis, browning characteristics, inflammatory status and adipokine secretion, and increases lipotoxicity. These age-dependent changes in adipose tissue are an important cause of insulin resistance and T2D. Understanding adipose tissue changes can help promote healthy aging process. This review summarizes changes in adipose tissue ascribable to aging, with a focus on the role of aging adipose tissue in insulin resistance and T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Humanos , Resistência à Insulina/fisiologia , Tecido Adiposo , Envelhecimento , Adipogenia/fisiologia
15.
Clin Cancer Res ; 30(4): 673-679, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38048044

RESUMO

In recent years, there has been increased interest in incorporation of backfilling into dose-escalation clinical trials, which involves concurrently assigning patients to doses that have been previously cleared for safety by the dose-escalation design. Backfilling generates additional information on safety, tolerability, and preliminary activity on a range of doses below the maximum tolerated dose (MTD), which is relevant for selection of the recommended phase II dose and dose optimization. However, in practice, backfilling may not be rigorously defined in trial protocols and implemented consistently. Furthermore, backfilling designs require careful planning to minimize the probability of treating additional patients with potentially inactive agents (and/or subtherapeutic doses). In this paper, we propose a simple and principled approach to incorporate backfilling into the Bayesian optimal interval design (BOIN). The design integrates data from the dose-escalation and backfilling components of the design and ensures that the additional patients are treated at doses where some activity has been seen. Simulation studies demonstrated that the proposed backfilling BOIN design (BF-BOIN) generates additional data for future dose optimization, maintains the accuracy of the MTD identification, and improves patient safety without prolonging the trial duration.


Assuntos
Neoplasias , Projetos de Pesquisa , Humanos , Teorema de Bayes , Simulação por Computador , Dose Máxima Tolerável , Relação Dose-Resposta a Droga , Neoplasias/tratamento farmacológico
16.
Plant Sci ; 340: 111965, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38142750

RESUMO

Drought stress is increasing worldwide due to global warming, which severely reduces apple (Malus domestica) yield. Clarifying the basis of drought tolerance in apple could accelerate the molecular breeding of drought-tolerant cultivars to maintain apple production. We identified a transcription factor MdWRKY50 by yeast two-hybrid (Y2H) assays as an interactor of the drought-tolerant protein MdWRKY17, and confirmed their interaction by bimolecular fluorescence complementation (BiFC) and pull-down assays. MdWRKY50 was induced by drought and when overexpressed in apple, conferred transgenic apple plants enhanced drought tolerance by directly binding to the promoter of anthocyanin synthetic gene Chalcone synthase (MdCHS) to upregulate its expression for higher anthocyanin. Increased anthocyanin relieves apple plants from oxidative damage under drought stress. MdWRKY50 RNA-interference transgenic apple plants showed opposite phenotypes. The dimerization of MdWRKY50 with mutated MdWRKY17DP mimicking drought-induced phosphorylation by the mitogen-activated protein kinase kinase 2 (MEK2)-MPK6 cascade, compared with MdWRKY17AP and MdWRKY17, further promoted anthocyanin biosynthesis, suggesting dimerization with MdWRKY17 makes MdWRKY50 more powerful in promoting anthocyanin biosynthesis under drought stress. Taken together, we isolated an entire MEK2-MAPK6-MdWRKY17-MdWRKY50-MdCHS pathway for drought tolerance and generated transgenic apple germplasm with enhanced drought tolerance and higher anthocyanin levels.


Assuntos
Malus , Malus/metabolismo , Antocianinas/metabolismo , Resistência à Seca , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
17.
Gait Posture ; 108: 177-182, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38100956

RESUMO

BACKGROUND: Children with unilateral spastic cerebral palsy (USCP) have muscle hypertonia, balance, and coordination defects that affect gross motor skills, especially walking. Understanding the gait characteristics and lower limb muscle activation patterns of USCP children can provide an objective and quantitative basis for patient assessment and treatment plan formulation. OBJECTIVE: This study compared the gait and lower limb muscle activation characteristics of children with USCP and with typical development (TD) during walking. METHODS: We recorded gait and sEMG data of 20 children with USCP, and 20 with typical development. sEMG signals were acquired from the bilateral tibialis anterior (TA) and lateral gastrocnemius muscles (LG) during walking. The root mean square (RMS) value, integrated electromyographic (iEMG) value and co-contraction ratio (CR) were used to evaluate muscle activity. Student's t Test and non-parametric rank sum Test were used to compare the differences between the data groups (significance level of 0.05). RESULTS: The stance time, step length, speed, single leg support time ratio, ground impact, pre-swing angle, and muscle strength of the affected side were significantly decreased compared to those of the unaffected side in children with USCP (P < 0.05), while the swing phase, muscle tonus of LG were significantly prolonged (P < 0.05). Compared with TD children, children with USCP exhibited reduced bilateral walking ability, particularly noticeable in their smaller pre-swing angle(P < 0.05), diminished muscle strength of the TA and LG, as well as LG spasms(P < 0.05). SIGNIFICANCE: Children with USCP have decreased ambulatory gait stability. Step length, pull acceleration, pre-swing angle, and CR can be used as sensitive indicators for gait assessment. Strengthening the TA muscle and reducing ankle spasm may help improve gait and postural stability in children with USCP.


Assuntos
Paralisia Cerebral , Criança , Humanos , Paralisia Cerebral/complicações , Marcha/fisiologia , Caminhada/fisiologia , Extremidade Inferior , Músculo Esquelético/fisiologia , Eletromiografia
18.
Polymers (Basel) ; 15(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37836004

RESUMO

Lithium-sulfur (Li-S) batteries are considered one of the most promising energy storage systems due to their high theoretical capacity, high theoretical capacity density, and low cost. However, challenges such as poor conductivity of sulfur (S) elements in active materials, the "shuttle effect" caused by lithium polysulfide, and the growth of lithium dendrites impede the commercial development of Li-S batteries. As a crucial component of the battery, the separator plays a vital role in mitigating the shuttle effect caused by polysulfide. Traditional polypropylene, polyethylene, and polyimide separators are constrained by their inherent limitations, rendering them unsuitable for direct application in lithium-sulfur batteries. Therefore, there is an urgent need for the development of novel separators. This review summarizes the applications of different separator preparation methods and separator modification methods in lithium-sulfur batteries and analyzes their electrochemical performance.

19.
Nano Lett ; 23(16): 7716-7724, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37539976

RESUMO

Graphene films that can theoretically block almost all molecules have emerged as promising candidate materials for moisture barrier films in the applications of organic photonic devices and gas storage. However, the current barrier performance of graphene films does not reach the ideal value. Here, we reveal that the interlayer distance of the large-area stacked multilayer graphene is the key factor that suppresses water permeation. We show that by minimizing the gap between the two monolayers, the water vapor transmission rate of double-layer graphene can be as low as 5 × 10-3 g/(m2 d) over an A4-sized region. The high barrier performance was achieved by the absence of interfacial contamination and conformal contact between graphene layers during layer-by-layer transfer. Our work reveals the moisture permeation mechanism through graphene layers, and with this approach, we can tailor the interlayer coupling of manually stacked two-dimensional materials for new physics and applications.

20.
J Orthop Surg Res ; 18(1): 547, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37518000

RESUMO

PURPOSE: To investigate the changes in 30° and 60° position sense in patients with anterior cruciate ligament (ACL) injury at different time points after injury and reconstruction. METHODS: Patients were divided into six groups according to time after ACL injury and reconstruction: group A (ACL injury 1.5-6 months), group B (ACL injury 6-12 months), group C (ACL injury > 12 months), group D (postoperative ACL reconstruction 1-6 months), group E (postoperative ACL reconstruction > 6 months), and group F consisting of 14 healthy adults (control group). The ability of the affected leg to reproduce the same joint position during knee flexion was tested using active joint position sense assays to assess proprioception in both the lower extremities of the patient or between groups. RESULTS: Proprioception decreased rapidly during the early stages of ACL injury. Significant difference in the affected side at 30° compared to the healthy side (Group A: 4.70 (4.78, 9.00) vs 4.15 (3.35, 6.13), P = 0.03; Group B: 2.90 (0.48, 4.56) vs 8.30 (4.18, 10.43), P = 0.001; Group E: 6.25 (2.55, 11.60) vs 9.60 (3.90, 12.73), P = 0.009). However, no significant differences were detected for a double lower limb contrast of 60° (Group A: 5.1 (1.00, 8.00) vs 3.00 (0.75, 3.55), P = 0.044). Finally, the affected side of patients in groups C, D and E had significant differences in position perception at 30° compared with healthy subjects (P < 0.01), and the affected side of patients in groups C and E had significant differences in position sense at 60° compared with healthy subjects (P < 0.01). CONCLUSION: ACL injury had a greater impact on the patient's 30° position sense, with only a small impact for 60°. Further, the early and middle proprioception recovery stages after ACL injury were the best before surgery. Finally, proprioception recovery training should be performed soon after injury.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Adulto , Humanos , Lesões do Ligamento Cruzado Anterior/cirurgia , Propriocepção , Extremidade Inferior/cirurgia , Articulação do Joelho/cirurgia
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