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1.
Biomaterials ; 314: 122852, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39357149

RESUMO

Alzheimer's Disease (AD) represents one of the most significant neurodegenerative challenges of our time, with its increasing prevalence and the lack of curative treatments underscoring an urgent need for innovative therapeutic strategies. Stem cells (SCs) therapy emerges as a promising frontier, offering potential mechanisms for neuroregeneration, neuroprotection, and disease modification in AD. This article provides a comprehensive overview of the current landscape and future directions of stem cell therapy in AD treatment, addressing key aspects such as stem cell migration, differentiation, paracrine effects, and mitochondrial translocation. Despite the promising therapeutic mechanisms of SCs, translating these findings into clinical applications faces substantial hurdles, including production scalability, quality control, ethical concerns, immunogenicity, and regulatory challenges. Furthermore, we delve into emerging trends in stem cell modification and application, highlighting the roles of genetic engineering, biomaterials, and advanced delivery systems. Potential solutions to overcome translational barriers are discussed, emphasizing the importance of interdisciplinary collaboration, regulatory harmonization, and adaptive clinical trial designs. The article concludes with reflections on the future of stem cell therapy in AD, balancing optimism with a pragmatic recognition of the challenges ahead. As we navigate these complexities, the ultimate goal remains to translate stem cell research into safe, effective, and accessible treatments for AD, heralding a new era in the fight against this devastating disease.

2.
Heart Lung Circ ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39394030

RESUMO

AIM: To report the safety and effectiveness of a modified Warden procedure. METHOD: Twenty-six (26) patients underwent modified Warden surgery at our centre from September 2017 to September 2021. In all patients, the superior vena cava (SVC) was reconstructed by turning the atrial wall in the main body of the right atrium upwards and applying fresh autologous pericardial patches. There were 13 male patients and 13 female patients, and the median age of the patients was 7.0 (range, 0.3-47.0) years. The median follow-up time after surgery was 47.0 (range, 32.0-80.0) months. RESULTS: The aortic cross-clamp time was 108.50±34.72 minutes, the cardiopulmonary bypass time was 154.81±41.65 minutes, the median postoperative mechanical ventilation time was 8.5 (range, 0.0-91.0) hours, the median intensive care unit stay was 43.5 (range, 15.0-352.0) hours, and the median length of postoperative hospital stay was 7.0 (range, 6.0-19.0) days. All patients were safely and successfully discharged from the hospital. No deaths or sinus node dysfunction occurred during the follow-up period. The mean gradient of the reconstructed SVC and/or the right pulmonary vein (PV) increased in eight patients and decreased to less than 1 mmHg in six patients. One (1) adult patient had already undergone two vascular interventions, and one child had persistent stenosis but did not undergo reoperation at the time of the study. In addition, two patients were subjected to pericardial windowing. CONCLUSIONS: A modified Warden technique using a right atrial flap and autologous pericardium effectively corrected the high-plane connection between the PVs and SVC. This technique effectively avoids sinus node dysfunction; however, a short-term increase in the differential pressure of the re-established SVC or PV after the procedure is acceptable, and reintervention is required only in rare cases.

3.
J Hazard Mater ; 480: 136012, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39366046

RESUMO

Manipulating materials of different dimensions into heterogeneous nanofiltration membranes with unique physicochemical properties and molecular sieving channels provides an effective way for accurate and fast molecular separation. Here we introduce a heterogeneous structure hybrid connection strategy to fabricate biodegradable wood-based covalent organic framework (COF) composite membranes. As a proof of concept, 3D Picea jezoensis (Siebold & Zucc.) Carrière was selected as the substrate of the membrane and in situ growth of 2D iCOF selective layers. Effective modulation of iCOF layers by 1D sulfonated polyaryletherketone (SPEEK-Na) using the "needle and thread" method. The rearrangement of the above multidimensional materials formed charge-regulated properties of laminar nano-channels and smooth hydrophilic contact area, thereby endowing specific molecular transport pathways and sieving capability for efficient dye/salt separation under ultra-low pressure of 0.5 bar. The wood-based heterostructured membranes exhibited high dye rejection (>97 %), low salt rejection (<10 %), and high permeance (172.34 L m-2 h-1 bar-1), which is superior to many reported dye/salt separation membrane materials. In addition, the system exhibited a certain degree of operational stability, good antifouling, and soil biodegradability. Overall, this work enables the design and fabrication of heterostructured separation membranes to be obtained from nature and used in nature, resulting in efficient and sustainable water purification applications.

4.
Environ Sci Technol ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39402705

RESUMO

Urban landscapes are high phosphorus (P) consumption areas and consequently generate substantial P-containing urban solid waste (domestic kitchen wastes, animal bones, and municipal sludge), due to large population. However, urbanization can also trap P through cultivated land loss and urban solid waste disposal. Trapped urban P is an overlooked and inaccessible P stock. Here, we studied how urbanization contributes to trapped urban P and how it affects the P cycle. We take China as a case study. Our results showed that China generated a total of 13 (±0.9) Tg urban trapped P between 1992-2019. This amounts to 6 (±0.5) % of the total consumed P and 9 (±0.6) % of the chemical fertilizer P used in China over that period. The loss of cultivated land accounted for 15% of the trapped urban P, and half of this was concentrated in three provinces: Shandong, Henan, and Hebei. This is primarily since nearly one-third of the newly expanded urban areas are located within these provinces. The remaining 85% of trapped urban P was associated with urban solid waste disposal. Our findings call for more actions to preserve fertile cultivated land and promote P recovery from urban solid waste through sound waste classification and recycling systems to minimize P trapped in urban areas.

5.
Heliyon ; 10(18): e37863, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39328540

RESUMO

Hydrogen energy, due to its clean and efficient nature, has shown great potential during the current transition period in the shipbuilding industry. However, the application of hydrogen energy in ship energy systems is influenced by variations in operational load and the integration of new energy sources during actual navigation. To address these issues, this paper focuses on optimizing and scheduling the operation of ships under various navigation conditions, considering the distributed nature of hydrogen energy. System simulations were conducted to model the photovoltaic (PV), proton exchange membrane fuel cells (PEMFCs), lithium batteries (LIBs), electrolytic cells (ECs), and energy storage modules of yacht energy systems. Component boundaries and objective functions were set, and two cases (excess photovoltaic state and constant power state) were designed to optimize and regulate the energy balance of hydrogen-powered yachts, enhancing their comprehensive utilization of renewable energy. By comparing the changes in ship energy under the two cases, it was concluded that case 1 ensures the maximum utilization of renewable energy. When photovoltaic power generation is insufficient, the PEMFC and LIB in the system provide the required power to achieve a supply-demand balance. Moreover, when PV power generation is sufficient, hydrogen energy is used to store renewable energy. The optimization method designed in this study can, to some extent, maximize the application of renewable energy in new energy yachts, ensuring the efficiency of the comprehensive energy system of new energy yachts, reducing emissions, and improving the sustainability and economic efficiency of the ships.

6.
Front Hum Neurosci ; 18: 1408818, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39290568

RESUMO

Upper limb actions require intersegmental coordination of the scapula, shoulders, elbows, forearms, wrists, and hand muscles. Stroke hemiparesis, presenting as an impairment of an intersegmentally coordinated voluntary movement, is associated with altered integrity of corticospinal tract (CST) transmission from the motor cortex (M1) to muscles. Motor evoked potentials (MEPs) elicited by M1 transcranial magnetic stimulation (TMS) of "at rest" muscles, or as a backup, during muscle contraction have been used to identify CST integrity and predict the outcome after hemiparesis, under the implicit assumption that MEPs present in only one or two muscles are manifest surrogates of CST integrity for other muscles of the upper limbs. This study presents a method for applying TMS during motor tasks that involve proximal and distal muscles. It focuses on evaluating multi-muscle electromyography (EMG) and MEPs across all task-relevant limb segments. Protocols are presented for assessing voluntary motor behavior in individuals with hemiparetic stroke using isometric, unimanual, bimanual, and "REST" conditions that broaden the concept of the degree of CST integrity in order to inform clinical prescription for neurorehabilitation and distinguish its potential as a prognostic tool. Data describing the recordings of multi-muscle transcranial magnetic stimulation induced motor evoked potentials (TMS-MEP) will be presented in a case of subacute hemiparetic stroke to elucidate our perspective.

7.
ChemSusChem ; : e202400909, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264637

RESUMO

Lactones has gained increasing attention in recent years due to wide application in polymer and pharmaceutical industries. Traditional synthetic methods of lactones often involve harsh operating temperature, use of strong alkalis and toxic oxidants. Therefore, lactonization of diols under milder conditions have been viewed as the most promising route for future commercialization. A variety of metal catalysts (Ru, Pt, Ir, Au, Fe, Cu, Co, and Zn) have been developed for highly efficient oxidant-, acceptor-, base- and additive-free lactonization processes. However, only a few initial attempts have been reported with no further details on catalytic mechanism being disclosed in literature. There demands a systematic study of the mechanistic details and the structure-function relationship to guide the catalyst design. In this work, we critically reviewed and discussed the structure-function relationship, the catalytic reaction mechanism, the catalyst stability, as well as the effect of oxidant and solvent for lactonization of diols. This work may provide additional insights for the development of other oxygen-containing functional molecules for material science and technologies.

8.
J Appl Genet ; 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39305455

RESUMO

Sorghum grain traits are important agronomic traits directly related to yield and are key factors affecting the brewing process of distill liquor. Exploring the genes controlling those traits is of great significance for understanding the genetic mechanism of sorghum grain development. In this study, we conducted genotyping using Super-GBS technology on a recombinant inbred lines (RILs) population derived from the cross between "BTx623" and "Hongyingzi," consisting of 205 lines. The grain-related traits of the RIL population were investigated in Guiyang, Anshun in Guizhou, and Ledong in Hainan in China. By inclusive composite interval mapping (ICIM) method, a total of 47 quantitative trait locus (QTL) related to four grain traits (thousand grain weight, grain length, grain width, and length-width ratio) were identified across 10 chromosomes. Among them, 20 important QTL were repeatedly detected in multiple traits or environments and distributed on chromosomes 1 (1), 2 (2), 3 (5), 4 (5), 5 (1), 6 (2), 7 (2), 8 (1), and 9 (1). Six candidate genes were identified within the confidence interval of these QTL, and they are homologous to genes controlling rice grain development (OsMADS1, RGG2, OsNST1, SMG1, OsGRF8, and OsAP2-39). The results provide a basis for further cloning and functional verification of these candidate genes.

9.
Bioengineering (Basel) ; 11(8)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39199763

RESUMO

BACKGROUND: Diffusion-weighted imaging (DWI), a pivotal component of multiparametric magnetic resonance imaging (mpMRI), plays a pivotal role in the detection, diagnosis, and evaluation of gastric cancer. Despite its potential, DWI is often marred by substantial anatomical distortions and sensitivity artifacts, which can hinder its practical utility. Presently, enhancing DWI's image quality necessitates reliance on cutting-edge hardware and extended scanning durations. The development of a rapid technique that optimally balances shortened acquisition time with improved image quality would have substantial clinical relevance. OBJECTIVES: This study aims to construct and evaluate the unsupervised learning framework called attention dual contrast vision transformer cyclegan (ADCVCGAN) for enhancing image quality and reducing scanning time in gastric DWI. METHODS: The ADCVCGAN framework, proposed in this study, employs high b-value DWI (b = 1200 s/mm2) as a reference for generating synthetic b-value DWI (s-DWI) from acquired lower b-value DWI (a-DWI, b = 800 s/mm2). Specifically, ADCVCGAN incorporates an attention mechanism CBAM module into the CycleGAN generator to enhance feature extraction from the input a-DWI in both the channel and spatial dimensions. Subsequently, a vision transformer module, based on the U-net framework, is introduced to refine detailed features, aiming to produce s-DWI with image quality comparable to that of b-DWI. Finally, images from the source domain are added as negative samples to the discriminator, encouraging the discriminator to steer the generator towards synthesizing images distant from the source domain in the latent space, with the goal of generating more realistic s-DWI. The image quality of the s-DWI is quantitatively assessed using metrics such as the peak signal-to-noise ratio (PSNR), structural similarity index (SSIM), feature similarity index (FSIM), mean squared error (MSE), weighted peak signal-to-noise ratio (WPSNR), and weighted mean squared error (WMSE). Subjective evaluations of different DWI images were conducted using the Wilcoxon signed-rank test. The reproducibility and consistency of b-ADC and s-ADC, calculated from b-DWI and s-DWI, respectively, were assessed using the intraclass correlation coefficient (ICC). A statistical significance level of p < 0.05 was considered. RESULTS: The s-DWI generated by the unsupervised learning framework ADCVCGAN scored significantly higher than a-DWI in quantitative metrics such as PSNR, SSIM, FSIM, MSE, WPSNR, and WMSE, with statistical significance (p < 0.001). This performance is comparable to the optimal level achieved by the latest synthetic algorithms. Subjective scores for lesion visibility, image anatomical details, image distortion, and overall image quality were significantly higher for s-DWI and b-DWI compared to a-DWI (p < 0.001). At the same time, there was no significant difference between the scores of s-DWI and b-DWI (p > 0.05). The consistency of b-ADC and s-ADC readings was comparable among different readers (ICC: b-ADC 0.87-0.90; s-ADC 0.88-0.89, respectively). The repeatability of b-ADC and s-ADC readings by the same reader was also comparable (Reader1 ICC: b-ADC 0.85-0.86, s-ADC 0.85-0.93; Reader2 ICC: b-ADC 0.86-0.87, s-ADC 0.89-0.92, respectively). CONCLUSIONS: ADCVCGAN shows excellent promise in generating gastric cancer DWI images. It effectively reduces scanning time, improves image quality, and ensures the authenticity of s-DWI images and their s-ADC values, thus providing a basis for assisting clinical decision making.

10.
Artigo em Inglês | MEDLINE | ID: mdl-39210580

RESUMO

The study aimed to assess the impact of changes in blood pressure on cardiovascular events in the Chinese population. It enrolled 33 179 Chinese participants aged ≥35 years (57.1% women) without CVD at baseline. BP status was defined according to the 2017 ACC/AHA hypertension guidelines. The type of BP change was defined as change in BP status from baseline to the end of follow-up, included stable BP <130/80, <130/80 to ≥130/80, ≥130/80 to <130/80 mm Hg, persistent BP ≥130/80 mm Hg. The hazard ratio (HR) of incident CVD by change in BP category was estimated using Cox proportional hazards and Fine-Gray models. During median follow-up of 3.17 years, 2023 CVD events occurred. Compared with BP <120/80, 120-129/<80 mm Hg at baseline (HR = 1.66, 95% CI: 1.09-2.53), 130-139/80-89 mm Hg (HR = 1.35, 95% CI: 0.94-1.95), and ≥140/90 mm Hg (HR = 2.46, 95% CI: 1.78-3.40) were risk factors for CVD. Compared with the group with stable BP <130/80 mm Hg, the risk of CVD was 1.88 (95% CI: 1.40-2.53) in the group with persistent BP ≥130/80 mm Hg and 1.40 (95% CI: 1.01-1.94) in the group of BP decreased to <130/80 mm Hg. These results showed that BP 120-129/<80, 130-139/80-89, and ≥140/90 mm Hg were associated with a high risk of CVD. Over time, persistent BP ≥130/80 mm Hg increased the risk of CVD, but a return to <130/80 mm Hg from hypertension decreased the risk of CVD.

11.
Colloids Surf B Biointerfaces ; 244: 114139, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39121571

RESUMO

Alzheimer's disease (AD) remains one of the most challenging neurodegenerative disorders to treat, with oxidative stress playing a significant role in its pathology. Recent advancements in nanoenzymes technology offer a promising approach to mitigate this oxidative damage. Nanoenzymes, with their unique enzyme-mimicking activities, effectively scavenge reactive oxygen species and reduce oxidative stress, thereby providing neuroprotective effects. This review delves into the underlying mechanisms of AD, focusing on oxidative stress and its impact on disease progression. We explore the latest developments in nanoenzymes applications for AD treatment, highlighting their multifunctional capabilities and potential for targeted delivery to amyloid-beta plaques. Despite the exciting prospects, the clinical translation of nanoenzymes faces several challenges, including difficulties in brain targeting, consistent quality production, and ensuring safety and biocompatibility. We discuss these limitations in detail, emphasizing the need for rigorous evaluation and standardized protocols. This paper aims to provide a comprehensive overview of the current state of nanoenzymes research in AD, shedding light on both the opportunities and obstacles in the path towards effective clinical applications.


Assuntos
Doença de Alzheimer , Estresse Oxidativo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Humanos , Estresse Oxidativo/efeitos dos fármacos , Animais , Enzimas/metabolismo , Enzimas/química , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas/química , Fármacos Neuroprotetores/farmacologia , Peptídeos beta-Amiloides/metabolismo
12.
Curr Res Food Sci ; 9: 100810, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39114432

RESUMO

Our meta-analysis aimed to assess the effectiveness of probiotics in weight loss and glucose and lipid metabolism in overweight or obese women. PubMed, EMBASE, Cochrane Library, and Web of Science were used from inception until March 2024 to identify randomized controlled trials (RCT's) literature. Finally, 11 RCTs were included. Following critical appraisal, a meta-analysis was conducted using the fixed effects model and the random effects model found that probiotic consumption significantly decreased waist circumference (WC) (SMD = -0.39 cm, 95% CI: -0.60, -0.18 cm, P < 0.00001, I2 = 33%), insulin (SMD = -0.45 mcU/ml; 95% CI: -0.72, -0.18 mcU/ml; P = 0.04, I2 = 40%) and low-density lipoprotein cholesterol (LDL-C) levels (SMD = -0.51 mmol/L; 95% CI: -0.92, -0.11 mmol/L; P = 0.02, I2 = 75%) in overweight or obese women. Moreover, subgroup analyses revealed that the effects of probiotic supplementation were significantly influenced by the intervention duration and diet and/or exercise intervention. This meta-analysis suggested that probiotic supplementation has a moderate and statistically significant effect on weight loss and glucose and lipid metabolism in overweight and obese women.

13.
Circ Res ; 135(6): 651-667, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39082138

RESUMO

BACKGROUND: ß-adrenergic receptor (ß-AR) overactivation is a major pathological cue associated with cardiac injury and diseases. AMPK (AMP-activated protein kinase), a conserved energy sensor, regulates energy metabolism and is cardioprotective. However, whether AMPK exerts cardioprotective effects via regulating the signaling pathway downstream of ß-AR remains unclear. METHODS: Using immunoprecipitation, mass spectrometry, site-specific mutation, in vitro kinase assay, and in vivo animal studies, we determined whether AMPK phosphorylates ß-arrestin-1 at serine (Ser) 330. Wild-type mice and mice with site-specific mutagenesis (S330A knock-in [KI]/S330D KI) were subcutaneously injected with the ß-AR agonist isoproterenol (5 mg/kg) to evaluate the causality between ß-adrenergic insult and ß-arrestin-1 Ser330 phosphorylation. Cardiac transcriptomics was used to identify changes in gene expression from ß-arrestin-1-S330A/S330D mutation and ß-adrenergic insult. RESULTS: Metformin could decrease cAMP/PKA (protein kinase A) signaling induced by isoproterenol. AMPK bound to ß-arrestin-1 and phosphorylated Ser330 with the highest phosphorylated mass spectrometry score. AMPK activation promoted ß-arrestin-1 Ser330 phosphorylation in vitro and in vivo. Neonatal mouse cardiomyocytes overexpressing ß-arrestin-1-S330D (active form) inhibited the ß-AR/cAMP/PKA axis by increasing PDE (phosphodiesterase) 4 expression and activity. Cardiac transcriptomics revealed that the differentially expressed genes between isoproterenol-treated S330A KI and S330D KI mice were mainly involved in immune processes and inflammatory response. ß-arrestin-1 Ser330 phosphorylation inhibited isoproterenol-induced reactive oxygen species production and NLRP3 (NOD-like receptor protein 3) inflammasome activation in neonatal mouse cardiomyocytes. In S330D KI mice, the ß-AR-activated cAMP/PKA pathways were attenuated, leading to repressed inflammasome activation, reduced expression of proinflammatory cytokines, and mitigated macrophage infiltration. Compared with S330A KI mice, S330D KI mice showed diminished cardiac fibrosis and improved cardiac function upon isoproterenol exposure. However, the cardiac protection exerted by AMPK was abolished in S330A KI mice. CONCLUSIONS: AMPK phosphorylation of ß-arrestin-1 Ser330 potentiated PDE4 expression and activity, thereby inhibiting ß-AR/cAMP/PKA activation. Subsequently, ß-arrestin-1 Ser330 phosphorylation blocks ß-AR-induced cardiac inflammasome activation and remodeling.


Assuntos
Proteínas Quinases Ativadas por AMP , Isoproterenol , Miócitos Cardíacos , beta-Arrestina 1 , Animais , Fosforilação , beta-Arrestina 1/metabolismo , beta-Arrestina 1/genética , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Isoproterenol/toxicidade , Isoproterenol/farmacologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Camundongos Endogâmicos C57BL , Masculino , Receptores Adrenérgicos beta/metabolismo , Serina/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Agonistas Adrenérgicos beta/toxicidade , Células Cultivadas , Transdução de Sinais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Humanos
14.
Microorganisms ; 12(7)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39065098

RESUMO

Ectomycorrhizal fungi have huge potential value, both nutritionally and economically, but most of them cannot be cultivated artificially. To better understand the influence of abiotic and biotic factors upon the growth of ectomycorrhizal fungi, mycosphere soil and bulk soil of five ectomycorrhizal fungi (Calvatia candida, Russula brevipes, Leucopaxillus laterarius, Leucopaxillus giganteus, and Lepista panaeola) were used as research objects for this study. Illumina MiSeq sequencing technology was used to analyze the community structure of the mycosphere and bulk soil bacteria of the five ectomycorrhizal fungi, and a comprehensive analysis was conducted based on soil physicochemical properties. Our results show that the mycosphere soil bacteria of the five ectomycorrhizal fungi are slightly different. Escherichia, Usitatibacter, and Bradyrhizobium are potential mycorrhizal-helper bacteria of distinct ectomycorrhizal fungi. Soil water content, soil pH, and available potassium are the main factors shaping the soil bacterial community of the studied ectomycorrhizal fungi. Moreover, from the KEGG functional prediction and LEfSe analysis, there are significant functional differences not only between the mycosphere soil and bulk soil. 'Biosynthesis of terpenoidsand steroids', 'alpha-Linolenic acid metabolism', 'Longevity regulating pathway-multiple species', 'D-Arginine and D-ornithine metabolism', 'Nitrotoluene degradation' and other functions were significantly different in mycosphere soil. These findings have pivotal implications for the sustainable utilization of ectomycorrhizal fungi, the expansion of edible fungus cultivation in forest environments, and the enhancement of derived economic benefits.

15.
Diagnostics (Basel) ; 14(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38928672

RESUMO

Currently, brain tumors are extremely harmful and prevalent. Deep learning technologies, including CNNs, UNet, and Transformer, have been applied in brain tumor segmentation for many years and have achieved some success. However, traditional CNNs and UNet capture insufficient global information, and Transformer cannot provide sufficient local information. Fusing the global information from Transformer with the local information of convolutions is an important step toward improving brain tumor segmentation. We propose the Group Normalization Shuffle and Enhanced Channel Self-Attention Network (GETNet), a network combining the pure Transformer structure with convolution operations based on VT-UNet, which considers both global and local information. The network includes the proposed group normalization shuffle block (GNS) and enhanced channel self-attention block (ECSA). The GNS is used after the VT Encoder Block and before the downsampling block to improve information extraction. An ECSA module is added to the bottleneck layer to utilize the characteristics of the detailed features in the bottom layer effectively. We also conducted experiments on the BraTS2021 dataset to demonstrate the performance of our network. The Dice coefficient (Dice) score results show that the values for the regions of the whole tumor (WT), tumor core (TC), and enhancing tumor (ET) were 91.77, 86.03, and 83.64, respectively. The results show that the proposed model achieves state-of-the-art performance compared with more than eleven benchmarks.

16.
BMC Plant Biol ; 24(1): 507, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844853

RESUMO

BACKGROUND: Powdery mildew, caused by Eeysiphe heraclei, seriously threatens Heracleum moellendorffii Hance. Plant secondary metabolites are essential to many activities and are necessary for defense against biotic stress. In order to clarify the functions of these metabolites in response to the pathogen, our work concentrated on the variations in the accumulation of secondary metabolites in H. moellendorffii during E. heraclei infection. RESULTS: Following E. heraclei infection, a significant upregulation of coumarin metabolites-particularly simple coumarins and associated genes was detected by RNA-seq and UPLC-MS/MS association analysis. Identifying HmF6'H1, a Feruloyl CoA 6'-hydroxylase pivotal in the biosynthesis of the coumarin basic skeleton through ortho-hydroxylation, was a significant outcome. The cytoplasmic HmF6'H1 protein was shown to be able to catalyze the ortho-hydroxylation of p-coumaroyl-CoA and caffeoyl-CoA, resulting in the formation of umbelliferone and esculetin, respectively. Over-expression of the HmF6'H1 gene resulted in increased levels of simple coumarins, inhibiting the biosynthesis of furanocoumarins and pyranocoumarins by suppressing PT gene expression, enhancing H. moellendorffii resistance to powdery mildew. CONCLUSIONS: These results established HmF6'H1 as a resistance gene aiding H. moellendorffii in combatting E. heraclei infection, offering additional evidence of feruloyl-CoA 6'-hydroxylase role in catalyzing various types of simple coumarins. Therefore, this work contributes to our understanding of the function of simple coumarins in plants' defense against powdery mildew infection.


Assuntos
Ascomicetos , Cumarínicos , Metaboloma , Doenças das Plantas , Transcriptoma , Cumarínicos/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Ascomicetos/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Apiaceae/metabolismo , Apiaceae/genética , Resistência à Doença/genética
17.
Anal Chim Acta ; 1307: 342640, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719417

RESUMO

BACKGROUND: The analysis of cell membrane permeability plays a crucial role in improving the procedures of cell cryopreservation, which will affect the specific parameter settings in loading, removal and cooling processes. However, existing studies have mostly focused on deriving permeability parameters through osmotic theoretical models and cell volume response analysis, and there is still a lack of the direct experimental evidence and analysis at the single-cell level regarding the migration of cryoprotectants. RESULTS: In this work, a side perfusion microfluidics chips combined with Raman spectroscopy system was built to monitor in situ the Raman spectroscopy of extracellular and intracellular solution during loading and elution process with different cryoprotectant solution systems (single and dual component). And it was found that loading a high concentration cryoprotectant solution system through a single elution cycle may result in significant residual protective agent, which can be mitigated by employing a multi-component formula but multiple elution operations are still necessary. Furthermore, the collected spectral signals were marked and analyzed to was perform preliminary relative quantitative analysis. The results showed that the intracellular concentration changes can be accurately quantified by the Raman spectrum and are closely related to the extracellular solution concentration changes. SIGNIFICANCE AND NOVELTY: By using the method of small flow perfusion (≤20 µL/min) in the side microfluidic chip after the gravity sedimentation of cells, the continuous loading and elution process of different cryoprotectants on chip and the spectral acquisition can be realized. The intracellular and extracellular concentrations can be quantified in situ based on the ratio of spectral peak intensities. These results indicate that spectroscopic analysis can be used to effectively monitor intracellular cryoprotectant residues.


Assuntos
Crioprotetores , Análise de Célula Única , Análise Espectral Raman , Análise Espectral Raman/métodos , Crioprotetores/química , Crioprotetores/farmacologia , Crioprotetores/isolamento & purificação , Dispositivos Lab-On-A-Chip , Humanos , Técnicas Analíticas Microfluídicas/instrumentação , Criopreservação/métodos , Animais
18.
Opt Lett ; 49(9): 2309-2312, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691706

RESUMO

Zinc gallium oxide (ZnGa2O4) has attracted considerable interest in deep-ultraviolet photodetectors, due to the ultrawide bandgap, high transmittance in the ultraviolet (UV) region, and excellent environmental stability. In this study, ZnGa2O4 thin films were deposited on p-GaN epi-layers using pulsed laser deposition, resulting in improved crystalline quality. The ZnGa2O4 film exhibited a bandgap of 4.93 eV, calculated through absorption spectra. A heterojunction photodetector (PD) was constructed, demonstrating a rectification effect, an on/off ratio of 12,697 at -5.87 V, a peak responsivity of 14.5 mA/W, and a peak detectivity of 1.14 × 1012 Jones (262 nm, -6 V). The PD exhibited a fast response time (39 ms) and recovery time (30 ms) under 262 nm illumination. The band diagram based on the Anderson model elucidates the photoresponse and carrier transport mechanism. This work paves the way for advancing next-generation optoelectronics.

19.
Sci Rep ; 14(1): 11455, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769329

RESUMO

Cone-beam computed tomography (CBCT) is a crucial component of adaptive radiation therapy; however, it frequently encounters challenges such as artifacts and noise, significantly constraining its clinical utility. While CycleGAN is a widely employed method for CT image synthesis, it has notable limitations regarding the inadequate capture of global features. To tackle these challenges, we introduce a refined unsupervised learning model called improved vision transformer CycleGAN (IViT-CycleGAN). Firstly, we integrate a U-net framework that builds upon ViT. Next, we augment the feed-forward neural network by incorporating deep convolutional networks. Lastly, we enhance the stability of the model training process by introducing gradient penalty and integrating an additional loss term into the generator loss. The experiment demonstrates from multiple perspectives that our model-generated synthesizing CT(sCT) has significant advantages compared to other unsupervised learning models, thereby validating the clinical applicability and robustness of our model. In future clinical practice, our model has the potential to assist clinical practitioners in formulating precise radiotherapy plans.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Redes Neurais de Computação , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Aprendizado de Máquina não Supervisionado
20.
Ren Fail ; 46(1): 2338217, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38584147

RESUMO

BACKGROUND: Elderly hemodialysis (HD) patients have a high risk of death. The effect of different types of HD membranes on survival is still controversial. The purpose of this study was to determine the relationship between the use of low-flux or high-flux membranes and all-cause and cardiovascular mortality in elderly hemodialysis patients. METHODS: This was a retrospective clinical study involving maintenance hemodialysis patients which were categorized into low-flux and high-flux groups according to the dialyzer they were using. Propensity score matching was used to balance the baseline data of the two groups. Survival rates were compared between the two groups, and the risk factors for death were analyzed by multivariate Cox regression. RESULTS: Kaplan-Meier survival analysis revealed no significant difference in all-cause mortality between the low-flux group and the high-flux group (log-rank test, p = 0.559). Cardiovascular mortality was significantly greater in the low-flux group than in the high-flux group (log-rank test, p = 0.049). After adjustment through three different multivariate models, we detected no significant difference in all-cause mortality. Patients in the high-flux group had a lower risk of cardiovascular death than did those in the low-flux group (HR = 0.79, 95% CI, 0.54-1.16, p = 0.222; HR = 0.58, 95% CI, 0.37-0.91, p = 0.019). CONCLUSIONS: High-flux hemodialysis was associated with a lower relative risk of cardiovascular mortality in elderly MHD patients. High-flux hemodialysis did not improve all-cause mortality rate. Differences in urea distribution volume, blood flow, and systemic differences in solute clearance by dialyzers were not further analyzed, which are the limitations of this study.


Assuntos
Doenças Cardiovasculares , Falência Renal Crônica , Humanos , Idoso , Falência Renal Crônica/complicações , Estudos Retrospectivos , Membranas Artificiais , Diálise Renal/efeitos adversos
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