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1.
Rejuvenation Res ; 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39003526

RESUMO

Chronic inflammation (inflammaging) is one of the important reasons for the development of age-related diseases and aging. Carrying out aging research and mining inflammatory markers can develop anti-aging intervention targets, thus promoting healthy aging. By comparing the levels of inflammatory proteome in the serum of Chinese long-living people over 90 years and elderly aged 60~79 which was detected by Olink platform, this study found that some pro-inflammatory or pro-aging proteins increased significantly in the long-living people, such as CXCL9, accompanied by a significant increase in the levels of several anti-inflammatory or anti-aging proteins, including FGF19 and FGF23, which confirmed that compared with elderly people, pro-inflammatory and anti-inflammatory (pro-aging and anti-aging) tend to be balanced in long-living people, thus reducing the risk of age-related diseases and prolonging the life span of the elderly. These differently expressed proteins could serve as therapeutic targets and monitoring indicators for anti-aging. At the same time, a few inflammatory protein markers, especially CXCL9 and OPG, could distinguish long-living and elderly correctly which could be used to predict lifespan combined with other anti-aging markers.

2.
Neuroreport ; 35(10): 601-611, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38813902

RESUMO

Danshen injection (DI) is effective in treating cardiovascular and cerebrovascular diseases, including ischemic stroke (IS), including IS, but its mechanism is unclear. A middle cerebral artery occlusion model was used to simulate ischemia/reperfusion (I/R) injury in SD rats. Overexpression of hypoxia-inducible factor 1α (HIF-1α) was achieved by AAV-HIF-1α. Rats were treated with DI or saline. Neurological scores and infarction rates were assessed. I/R damage was examined by HE, 2,3,5-triphenyltetrazolium and Nissl stainings. Expression levels of relative proteins [TNF-α, IL-6, IL-1ß, SOD, MDA, ROS, HIF-1α, CXC chemokine receptor 4 (CXCR4) and NF-κB] were measured. DI treatment improved neurological scores and reduced infarction rates, suggesting that it inhibits inflammation and oxidative stress. The expression levels of HIF-1α, CXCR4 and NF-κB were decreased. However, the effectiveness of DI on inflammation inhibition was lost after HIF-1α overexpression. DI may directly target HIF-1α to suppress neuroinflammation and reduce I/R injury by suppressing the HIF-1α/CXCR4/NF-κB signaling pathway.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , NF-kappa B , Doenças Neuroinflamatórias , Ratos Sprague-Dawley , Receptores CXCR4 , Traumatismo por Reperfusão , Salvia miltiorrhiza , Transdução de Sinais , Animais , Receptores CXCR4/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Ratos , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/administração & dosagem , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/tratamento farmacológico
3.
Phys Chem Chem Phys ; 26(11): 8891-8899, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38426345

RESUMO

Mid-ultraviolet light (290-320 nm) can promote human vitamin D synthesis, which helps in the prevention and treatment of rickets and cartilage disease. For people who lack sufficient ultraviolet radiation all year round, it is significant to supplement the ultraviolet component in daily lighting sources. However, there are few luminous materials showing a combination of mid-ultraviolet light and white light emission on the market. Here, we designed a new material, Y2Sr(Ga1-yAly)4SiO12:xPr3+ (YSGAS:xPr3+), which achieves dual emission of 320 nm ultraviolet and white light from a single substrate with a single doped phosphor. Without Al3+ ions, the emission intensity of the Y2SrGa4SiO12:xPr3+ phosphor shows a contribution-dependent relationship, and concentration quenching due to exchange interaction. The crystal field environment was regulated by partially replacing Ga3+ ions with Al3+ ions. After introducing Al3+, YSGAS:xPr3+ phosphors exhibit dual ultraviolet emission (320 nm) and visible light emission. The emission color of YSGAS:xPr3+ can be adjusted by changing the Al3+ concentration, and Y2Sr(Ga0.6Al0.4)4SiO12:1%Pr3+ emits both ultraviolet light and white light. The LED device prepared by using the YSGAS:Pr3+ phosphor and chips shows a color temperature of 4858 K and appropriate CIE coordinates of (0.3474, 0.3390), indicating wide application prospects in the field of "health lighting" for particular populations.

4.
Small ; : e2400505, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477685

RESUMO

Ammonia production by electrocatalytic nitrate reduction reaction (NO3 RR) in water streams is anticipated as a zero-carbon route. Limited by dilute nitrate in natural sewage and the electrostatic repulsion between NO3 - and cathode, NO3 RR can hardly be achieved energy-efficiently. The hydrophilic Cu@CuCoO2 nano-island dispersed on support can enrich NO3 - and produce a sensitive current response, followed by electrosynthesis of ammonia through atomic hydrogen (*H) is reported. The accumulated NO3 - can be partially converted to NO2 - without external electric field input, confirming that the Cu@CuCoO2 nano-island can strongly bind NO3 - and then trigger the reduction via dynamic evolution between Cu-Co redox sites. Through the identification of intermediates and theoretical computation. it is found that the N-side hydrogenation of *NO is the optimal reaction step, and the formation of N─N dimer may be prevented. An NH3 product selectivity of 93.5%, a nitrate conversion of 96.1%, and an energy consumption of 0.079 kWh gNH3 -1 is obtained in 48.9 mg-N L-1 naturally nitrate-polluted streams, which outperforms many works using such dilute nitrate influent. Conclusively, the electrocatalytic system provides a platform to guarantee the self-sufficiency of dispersed ammonia production in agricultural regions.

5.
Front Bioeng Biotechnol ; 11: 1196922, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37614630

RESUMO

The research on biomimetic robots, especially soft robots with flexible materials as the main structure, is constantly being explored. It integrates multi-disciplinary content, such as bionics, material science, mechatronics engineering, and control theory, and belongs to the cross-disciplinary field related to mechanical bionics and biological manufacturing. With the continuous development of various related disciplines, this area has become a hot research field. Particularly with the development of practical technologies such as 3D printing technology, shape memory alloy, piezoelectric materials, and hydrogels at the present stage, the functions and forms of soft robots are constantly being further developed, and a variety of new soft robots keep emerging. Soft robots, combined with their own materials or structural characteristics of large deformation, have almost unlimited degrees of freedom (DoF) compared with rigid robots, which also provide a more reliable structural basis for soft robots to adapt to the natural environment. Therefore, soft robots will have extremely strong adaptability in some special conditions. As a type of robot made of flexible materials, the changeable pose structure of soft robots is especially suitable for the large application environment of the ocean. Soft robots working underwater can better mimic the movement characteristics of marine life in the hope of achieving more complex underwater tasks. The main focus of this paper is to classify different types of underwater organisms according to their common motion modes, focusing on the achievements of some bionic mechanisms in different functional fields that have imitated various motion modes underwater in recent years (e.g., the underwater sucking glove, the underwater Gripper, and the self-powered soft robot). The development of various task types (e.g., grasping, adhesive, driving or swimming, and sensing functions) and mechanism realization forms of the underwater soft robot are described based on this article.

6.
Sci Total Environ ; 900: 165910, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37524186

RESUMO

The contamination of heavy metal lead has a serious impact on the natural environment and organisms. Among various materials for lead removal, animal bone derived hydroxyapatite has received extensive attention. However, there are different opinions among researchers regarding the mechanism of lead removal by hydroxyapatite, possibly due to varying initial lead concentrations used in different studies and lack of accuracy in the study of lead removal mechanisms. In present work, we synthesized a carbon-containing hydroxyapatite (CHAP) through pyrolysis of bovine bone with excellent lead removal efficiency, and further investigated the lead removal mechanism of CHAP under high and low initial lead concentrations by combining XRD Rietveld refinement, FTIR, XPS, HRTEM etc. methods. The results showed that under low initial Pb2+ concentration condition, the main mechanism of lead removal by CHAP was chemical precipitation (94.1 %), with small contributions of lead complexation with carbon functional groups and cation-π interactions on the amorphous carbon in CHAP, and surface adsorption on the precipitates. Under high initial Pb2+ concentration condition, chemical precipitation remained the main mechanism (74.68 %), but the contributions of the other three mechanisms increased, and ion exchange appeared in the later stage of the removal process. This study provides new insights on the lead immobilization mechanism by CHAP at different initial Pb2+ concentrations in water.

7.
Environ Sci Technol ; 56(20): 14797-14807, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36175172

RESUMO

The conversion of nitrate to ammonia can serve two important functions: mitigating nitrate pollution and offering a low energy intensity pathway for ammonia synthesis. Conventional ammonia synthesis from electrocatalytic nitrate reduction reactions (NO3RR) is often impeded by incomplete nitrate conversion, sluggish kinetics, and the competition of hydrogen evolution reactions. Herein, atomic Cu sites anchored on micro-/mesoporous nitrogen-doped carbon (Cu MNC) with fine-tuned hydrophilicity, micro-/mesoporous channels, and abundant Cu(I) sites were synthesized for selective nitrate reduction to ammonia, achieving ambient temperature and pressure hydrogenation of nitrate. Laboratory experiments demonstrated that the catalyst has an ammonia yield rate per active site of 5466 mmol gCu-1 h-1 and transformed 94.8% nitrate in wastewater containing 100 mg-N L-1 to near drinking water standard (MCL of 5 mg-N L-1) at -0.64 V vs RHE. Extended X-ray absorption fine structure (EXAFS) and theoretical calculations showed that the coordination environment of Cu(I) sites (Cu(I)-N3C1) localizes the charge around the central Cu atoms and adsorbs *NO3 and *H onto neighboring Cu and C sites with balanced adsorption energy. The Cu(I)-N3C1 moieties reduce the activation energy of rate-limiting steps (*HNO3 → *NO2, *NH2 → *NH3) compared with conventional Cu(II)-N4 and lead to a thermodynamically favorable process to NH3. The as-prepared electrocatalytic cell can run continuously for 84 h (14 cycles) and produce 21.7 mgNH3 with only 5.64 × 10-3 kWh energy consumption, suitable for decentralized nitrate removal and ammonia synthesis from nitrate-containing wastewater.


Assuntos
Água Potável , Nitratos , Amônia/química , Carbono , Cobre/química , Hidrogênio , Hidrogenação , Nitratos/química , Nitrogênio , Dióxido de Nitrogênio , Óxidos de Nitrogênio , Águas Residuárias
8.
Comput Methods Programs Biomed ; 217: 106698, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35217304

RESUMO

BACKGROUND AND OBJECTIVE: Neoadjuvant chemotherapy (NAC) is a valuable treatment approach for locally advanced breast cancer. Contrast-enhanced ultrasound (CEUS) potentially enables the assessment of therapeutic response to NAC. In order to evaluate the response accurately, quantitatively and objectively, a method that can effectively compensate motions of breast cancer in CEUS videos is urgently needed. METHODS: We proposed the four-quadrant fast compressive tracking (FQFCT) approach to automatically perform CEUS video tracking and compensation for mice undergoing NAC. The FQFCT divided a tracking window into four smaller windows at four quadrants of a breast lesion and formulated the tracking at each quadrant as a binary classification task. After the FQFCT of breast cancer videos, the quantitative features of CEUS including the mean transit time (MTT) were computed. All mice showed a pathological response to NAC. The features between pre- (day 1) and post-treatment (day 3 and day 5) in these responders were statistically compared. RESULTS: When we tracked the CEUS videos of mice with the FQFCT, the average tracking error of FQFCT was 0.65 mm, reduced by 46.72% compared with the classic fast compressive tracking method (1.22 mm). After compensation with the FQFCT, the MTT on day 5 of the NAC was significantly different from the MTT before NAC (day 1) (p = 0.013). CONCLUSIONS: The FQFCT improves the accuracy of CEUS video tracking and contributes to the computer-aided response evaluation of NAC for breast cancer in mice.


Assuntos
Neoplasias da Mama , Terapia Neoadjuvante , Animais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Computadores , Meios de Contraste , Feminino , Humanos , Camundongos , Terapia Neoadjuvante/métodos , Resultado do Tratamento , Ultrassonografia/métodos , Ultrassonografia Mamária/métodos
9.
Commun Biol ; 4(1): 415, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33772211

RESUMO

Approaches to reliably predict the developmental potential of embryos and select suitable embryos for blastocyst culture are needed. The development of time-lapse monitoring (TLM) and artificial intelligence (AI) may help solve this problem. Here, we report deep learning models that can accurately predict blastocyst formation and usable blastocysts using TLM videos of the embryo's first three days. The DenseNet201 network, focal loss, long short-term memory (LSTM) network and gradient boosting classifier were mainly employed, and video preparation algorithms, spatial stream and temporal stream models were developed into ensemble prediction models called STEM and STEM+. STEM exhibited 78.2% accuracy and 0.82 AUC in predicting blastocyst formation, and STEM+ achieved 71.9% accuracy and 0.79 AUC in predicting usable blastocysts. We believe the models are beneficial for blastocyst formation prediction and embryo selection in clinical practice, and our modeling methods will provide valuable information for analyzing medical videos with continuous appearance variation.


Assuntos
Algoritmos , Blastocisto/metabolismo , Aprendizado Profundo , Desenvolvimento Embrionário , Imagem com Lapso de Tempo , Humanos
10.
Ann Transl Med ; 9(2): 108, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33569410

RESUMO

BACKGROUND: Transthoracic echocardiography (TTE) is widely used in clinics to evaluate left ventricular hypertrophy (LVH). However, TTE is usually insufficient for the etiological diagnoses when morphological and functional features are nonspecific. With the booming of computer science and artificial intelligence (AI), previous literature has reported the application of radiomics based on cardiac magnetic resonance imaging, cardiac computed tomography and TTE in diagnosing several myocardial abnormalities, such as myocardial infarction, myocarditis, cardiac amyloidosis, and hypertrophic cardiomyopathy (HCM). In this study, we explored the possibility of using myocardial texture features in differentiating HCM, hypertensive heart disease (HHD) and uremic cardiomyopathy (UCM) based on echocardiography. To our knowledge, this was the first study to explore TTE myocardial texture analysis for multiple LVH etiology differentiation. METHODS: TTE images were reviewed retrospectively from January 2018 to collect 50 cases for each group of HHD, HCM and UCM. The apical four chamber view was retrieved. Seventeen first-order statistics and 60 gray level co-occurrence matrix (GLCM) features were extracted for statistics and classification test by support vector machine (SVM). RESULTS: Of all the parameters, entropy of brightness (EtBrt), standard deviation (Std), coefficient of variation (CoV), skewness (Skew), contrast7 (Cont7) and homogeneity5 (Hm5) were found statistically significant among the three groups (all P<0.05) and with acceptable reproducibility (intraobserver and interobserver ICC >0.50). As a result, HCM showed the most homogeneous myocardial texture, and was significantly different from HHD and UCM (all six features: P≤0.005). HHD appeared slightly more homogeneous than UCM, as only EtBrt and CoV were significant (P=0.011 and P=0.008). According to higher areas under the receiver operating characteristic curve (AUC) (>0.50), EtBrt, Std, and CoV were selected for test of classification as a combination of features. The AUC derived from SVM model was slightly improved compared with those of EtBrt, Std and CoV individually. CONCLUSIONS: AI-based myocardial texture analysis using ultrasonic images may be a potential approach to aiding LVH etiology differentiation.

11.
Front Oncol ; 10: 1719, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042816

RESUMO

Purpose: To explore the value of ultrasound radiomics in the preoperative identification of true and pseudo gallbladder polyps and to evaluate the associated diagnostic accuracy. Methods: Totally, 99 pathologically proven gallbladder polyps in 96 patients were enrolled, including 58 cholesterol polyps (55 patients) and 41 gallbladder tubular adenomas (41 patients). Features on preoperative ultrasound images, including spatial and morphological features, were acquired for each lesion. Following this, two-stage feature selection was adopted using Fisher's inter-intraclass variance ratios and Z-scores for the selection of intrinsic features important for differential diagnosis achievement with support vector machine use. Results: Eighty radiomic features were extracted from each polyp. Eight intrinsic features were identified after two-stage selection. The contrast 14 (Cont14) and entropy 6 (Entr6) values in the cholesterol polyp group were significantly higher than those in the gallbladder adenoma group (4.063 ± 1.682 vs. 2.715 ± 1.867, p < 0.001 for Cont14; 4.712 ± 0.427 vs. 4.380 ± 0.720, p = 0.003 for Entr6); however, the homogeneity 13 (Homo13) and energy 8 (Ener8) values in the cholesterol polyp group were significantly lower (0.500 ± 0.069 vs. 0.572 ± 0.057, p < 0.001 for Homo13; 0.050 ± 0.023 vs. 0.068 ± 0.038, p = 0.002 for Ener8). These results indicate that the pixel distribution of cholesterol polyps was more uneven than that of gallbladder tubular adenomas. The dispersion degree was also significantly lower in the cholesterol polyp group than the gallbladder adenoma group (0.579 ± 0.054 vs. 0.608 ± 0.041, p = 0.005), indicating a lower dispersion of high-intensity areas in the cholesterol polyps. The long axis length of the fitting ellipse (Maj.Len), diameter of a circle equal to the lesion area (Eq.Dia) and perimeter (Per) values in the cholesterol polyp group were significantly lower than those in the gallbladder adenoma group (0.971 ± 0.485 vs. 1.738 ± 0.912, p < 0.001 for Maj.Len; 0.818 ± 0.393 vs. 1.438 ± 0.650, p < 0.001 for Eq.Dia; 2.637 ± 1.281 vs. 5.033 ± 2.353, p < 0.001 for Per), demonstrating that the cholesterol polyps were smaller and more regular in terms of morphology. The classification accuracy, sensitivity, specificity, and area under the curve values were 0.875, 0.885, 0.857, and 0.898, respectively. Conclusions: Ultrasound radiomic analysis based on the spatial and morphological features extracted from ultrasound images effectively contributed to the preoperative diagnosis of true and pseudo gallbladder polyps and may be valuable in their clinical management.

12.
Chem Commun (Camb) ; 55(59): 8532-8535, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31232417

RESUMO

Organic crystals are generally considered to be brittle, inelastic materials, which pose challenges for application in flexible devices. Inspired by α helical proteins for their key structural role in flexible hair, here, we describe the construction of a spring-like hydrogen bonded network through the self-assembly of a-OH/e-OH cyclohexanol derivatives.

13.
Chem Commun (Camb) ; 53(91): 12266-12269, 2017 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-29058012

RESUMO

Cocrystallization of nifedipine (NFD) and isonicotinamide (INA) resulted in two monotropic cocrystal polymorphs. The thermodynamically more stable polymorph presents superior photostability compared to the other. Cocrystallization can be an efficient approach to address the stability deficit of dihydropyridine drugs.


Assuntos
Bloqueadores dos Canais de Cálcio/química , Di-Hidropiridinas/química , Niacinamida/química , Nifedipino/química , Cristalização , Conformação Molecular , Oxirredução , Processos Fotoquímicos , Termodinâmica
14.
Chem Commun (Camb) ; 52(17): 3572-5, 2016 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26845759

RESUMO

Drug-drug co-crystallization could realize combination drugs at a molecular level. Two polymorphic co-crystals between VD2 and VD3 were successfully designed and synthesized. These enantiotropic polymorphs exhibit significantly different physicochemical stabilities.


Assuntos
Colecalciferol/química , Cristalização , Ergocalciferóis/química , Preparações Farmacêuticas/química , Cromatografia Líquida de Alta Pressão , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Difração de Pó , Termogravimetria
15.
ScientificWorldJournal ; 2014: 498934, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25379536

RESUMO

A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine.


Assuntos
Ar Comprimido , Desenho de Equipamento/instrumentação , Modelos Estatísticos , Simulação por Computador , Humanos , Pressão , Torque , Emissões de Veículos
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