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1.
Materials (Basel) ; 17(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38730838

RESUMO

Multi-material additive manufacturing using heterogeneous powders as raw materials is one of the important development directions of metal additive manufacturing technology. The evaporation behavior of heterogeneous powders in the selective laser melting (SLM) process has a significant influence on the accuracy of chemical composition control and the quality of the final product. In this paper, the fusion process of Fe20Mn (80 wt.% Fe and 20 wt.% Mn) heterogeneous powder, Fe and Mn elemental powders, and Fe20Mn pre-alloyed powder is numerically simulated using FLOW-3D® software and partially validated through SLM experimental results. The morphology and the characteristics of the flow field and temperature field in the melt pool for four kinds of powder materials are analyzed. The influence of the elemental evaporation behavior of different powders on the mass loss of the Mn element is discussed. The results show that the excessive accumulation of heat increases the maximum temperature of the melt pool, thus increasing mass loss. The Fe20Mn heterogeneous powder has a wider heat-affected zone and a higher peak value of temperature, nearly 400 K higher than that of the Fe20Mn pre-alloyed powders, which exhibits an intensive evaporation behavior. The mass loss of the Mn element obtained from the SLM experiment for Fe20Mn heterogeneous powders forming parts is more than the Fe20Mn pre-alloyed powders' forming parts for different laser powers, up to 17 wt.% at P = 120 W. This tendency is consistent with the numerical analysis of the effect of evaporation behavior of Fe-Mn heterogeneous powder during the SLM process. This study provides the necessary theoretical reference and process guidance for realizing the precise control of the SLM composition of a heterogeneous powder in multi-material additive manufacturing caused by evaporation behavior.

2.
ACS Appl Mater Interfaces ; 14(39): 44622-44631, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36129520

RESUMO

Near-infrared (NIR) long persistent luminescent (LPL) materials have attracted the interest of many researchers as they have potential applications in many aspects. However, majority of studies on Cr3+ ion-doped LPL materials have focused on Cr3+ in an octahedral site, and the luminescence is limited to the short-wavelength NIR-I region (700-900 nm), which is detrimental to fully explore Cr3+ ion-doped LPL materials with potential applications. In this work, a novel ultra-broadband NIR LPL material, Na2CaGe6O14 (NCGO):x%Cr3+, was successfully designed and synthesized, covering the luminescence range of 600-1200 nm and having the best afterglow duration of more than 10 h. Combining the luminescence lifetime with the low-temperature spectrum, it was concluded that the luminescence of NCGO:Cr3+ consists of the co-emission of Cr3+ in octahedra and tetrahedra. And it was confirmed by electron paramagnetic resonance (EPR) spectrum and X-ray absorption near-edge spectrum (XANES). The application prospects of NCGO:x%Cr3+ in many aspects were investigated in detail. This work could not only give a reference for researchers to study Cr3+ luminescence in multiple coordination but also provide a new strategy for obtaining new ultra-broadband NIR LPL materials.

3.
Nutrients ; 14(16)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36014880

RESUMO

Increased oxidative stress and platelet apoptotic in middle-aged and elderly adults are important risk factors for atherosclerotic cardiovascular disease (ASCVD). Therefore, it is of great significance to control the oxidative stress and platelet apoptosis in middle-aged and elderly adults. Previous acute clinical trials have shown that water-soluble tomato concentrate (WSTC) from fresh tomatoes could exert antiplatelet benefits after 3 h or 7 h, but its effects on platelet apoptosis and oxidative stress are still unknown, especially in healthy middle-aged and elderly adults. This current study aimed to examine the efficacies of WSTC on platelet apoptosis and oxidative stress in healthy middle-aged and elderly adults via a randomized double-blinded placebo-controlled crossover clinical trial (10 weeks in total). A total of 52 healthy middle-aged and elderly adults completed this trial. The results showed that WSTC could increase the serum total antioxidant capacity levels (p < 0.05) and decrease the serum malondialdehyde levels (p < 0.05) after a 4-week WSTC supplementation in healthy middle-aged and elderly adults. Platelet endogenous reactive oxygen species generation (p < 0.05), mitochondrial membrane potential dissipation (p < 0.05) and phosphatidylserine exposure (p < 0.05) were attenuated. In addition, our present study also found that WSTC could inhibit platelet aggregation and activation induced by collagen or ADP after intervention (p < 0.05), while having no effects on adverse events (p > 0.05). The results suggest that WSTC can inhibit oxidative stress and its related platelet apoptosis, which may provide a basis for the primary prevention of WSTC in ASCVD.


Assuntos
Antioxidantes , Solanum lycopersicum , Adulto , Idoso , Antioxidantes/farmacologia , Apoptose , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Pessoa de Meia-Idade , Estresse Oxidativo , Água/farmacologia
4.
Front Nutr ; 9: 891241, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35719156

RESUMO

Background and Aims: Platelets are linked to atherosclerotic development and pathological thrombosis. Single dose of water-soluble tomato extract (WTE) which is a natural extraction can exert anti-platelet effects after 3 or 7 h in British healthy people. However, the effects of WTE supplementation on platelet function in Chinese healthy middle-aged and older individuals have not been studied, and the effects or safety of 4-week WTE supplementation also remain unclear. The present study aims to determine the effects of WTE on platelet function, and explore the safety of 4-week WTE supplementation in Chinese healthy middle-aged and older individuals. Methods: A randomized, double-blinded, and crossover clinical trial was conducted. Firstly, 105 individuals were randomly divided into two groups that received WTE (150 mg/day) or placebo for 4 weeks. Then, after a washout period of 2 weeks, two groups exchanged groups and continued for another 4-week intervention. Platelet aggregation, P-selectin, activated GPIIbIIIa, plasma platelet factor 4 (PF4), ß-thromboglobulin (ß-TG), and thromboxane B2 (TXB2) were tested at baseline, 4, 6, and 10 weeks. Results: Compared with the placebo group, 150 mg/day WTE supplement for 4 weeks significantly reduced ADP-induced or collagen-induced platelet aggregation (-10.8 ± 1.8 or -3.9 ± 1.5%, P < 0.05), ADP-induced or collagen-induced platelet P-selectin expression (-6.9 ± 1.5 or -6.6 ± 1.3%, P < 0.05), ADP-induced or collagen-induced activated GPIIbIIIa (-6.2 ± 2.0 or -3.8 ± 2.0%, P < 0.05). Besides, 4-week intervention of 150 mg WTE per day also resulted in significant reductions in plasma PF4 (-120.6 ± 33.2 ng/mL, P < 0.05) and ß-TG (-129.7 ± 27.5 ng/mL, P < 0.05) and TXB2 (-42.0 ± 4.0 ng/mL, P < 0.05), while had no effects on coagulation function and liver or renal function. Interestingly, 2-week washout period is enough to reverse the inhibitory effect of 4-week WTE supplementation on platelet function. Conclusion: WTE supplementation for 4 weeks could moderately reduce platelet activation, aggregation, and granule secretion in Chinese healthy middle-aged and older individuals, and these effects are safe. After 2-week washout period, the inhibitory effect of 4-week WTE on platelet function can be eliminated. Clinical Trial Registration: [http://www.chictr.org.cn/], identifier [ChiCTR-POR-17012927].

5.
EBioMedicine ; 70: 103533, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34392146

RESUMO

BACKGROUND: Dyslipidemia induces platelet hyperactivation and hyper-aggregation, which are linked to thrombosis. Anthocyanins could inhibit platelet function in vitro and in mice fed high-fat diets with their effects on platelet function in subjects with dyslipidemia remained unknown. This study aimed to investigate the effects of different doses of anthocyanins on platelet function in individuals with dyslipidemia. METHODS: A double-blind, randomized, controlled trial was conducted. Ninety-three individuals who were initially diagnosed with dyslipidemia were randomly assigned to placebo or 40, 80, 160 or 320 mg/day anthocyanin groups. The supplementations were anthocyanin capsules (Medox, Norway). Platelet aggregation by light aggregometry of platelet-rich plasma, P-selectin, activated GPⅡbⅢa, reactive oxygen species (ROS), and mitochondrial membrane potential were tested at baseline, 6 weeks and 12 weeks. FINDINGS: Compared to placebo group, anthocyanins at 80 mg/day for 12 weeks reduced collagen-induced platelet aggregation (-3.39±2.36%) and activated GPⅡbⅢa (-8.25±2.45%) (P < 0.05). Moreover, compared to placebo group, anthocyanins at 320 mg/day inhibited collagen-induced platelet aggregation (-7.05±2.38%), ADP-induced platelet aggregation (-7.14±2.00%), platelet ROS levels (-14.55±1.86%), and mitochondrial membrane potential (7.40±1.56%) (P < 0.05). There were dose-response relationships between anthocyanins and the attenuation of platelet aggregation, mitochondrial membrane potential and ROS levels (P for trend <0.05). Furthermore, significantly positive correlations were observed between changes in collagen-induced (r = 0.473) or ADP-induced (r = 0.551) platelet aggregation and ROS levels in subjects with dyslipidemia after the 12-week intervention (P < 0.05). INTERPRETATION: Anthocyanin supplementation dose-dependently attenuates platelet function, and 12-week supplementation with 80 mg/day or more of anthocyanins can reduce platelet function in individuals with dyslipidemia. FUNDING: None.


Assuntos
Antocianinas/farmacologia , Dislipidemias/tratamento farmacológico , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Adulto , Idoso , Antocianinas/administração & dosagem , Antocianinas/uso terapêutico , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Selectina-P/sangue , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/uso terapêutico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Espécies Reativas de Oxigênio/sangue
6.
Nutrients ; 13(7)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202823

RESUMO

Little is known about which currently available a priori dietary indexes provide best guidance for reducing cardiometabolic risk factors (CMRF) among hyperlipidemic patients. This study was designed to compare the associations between four a priori dietary indexes, including Diet Balance Index (DBI-16), Chinese Healthy Eating Index (CHEI), Mediterranean Diet Score (MDS) and Dietary Approaches to Stop Hypertension (DASH) and CMRF among hyperlipidemic patients. A total of 269 participants were enrolled into the cross-sectional study. DBI-16, CHEI, MDS, and DASH scores were calculated using established methods. CMRF was measured using standard methods. DBI-total scores (DBI-TS) were inversely associated with triglyceride concentrations and TC:HDL-C ratio, and positively associated with HDL-C and ApoA1 concentrations (all p < 0.05), while the results for DBI-low bound scores (DBI-LBS) were opposite. DBI-high bound scores (DBI-HBS) and DASH scores were positively and inversely associated with glucose concentrations, respectively (both p < 0.05). Higher diet quality distance (DQD) was positively associated with higher TC, LDL-C and ApoB concentrations, and TC:HDL-C and LDL-C:HDL-C ratios, and lower HDL-C and ApoA1 concentrations and ApoA1:ApoB ratio (all p < 0.05). CHEI scores were inversely associated with triglyceride concentrations (p = 0.036). None of the dietary indexes was associated with blood pressures. DBI-16 provided most comprehensive evaluations of the overall diet quality and balance for optimizing cardiometabolic health among hyperlipidemic individuals.


Assuntos
Dieta Saudável/métodos , Hiperlipidemias/dietoterapia , Avaliação Nutricional , Apolipoproteína A-I/sangue , Fatores de Risco Cardiometabólico , HDL-Colesterol/sangue , Estudos Transversais , Dieta Mediterrânea/estatística & dados numéricos , Abordagens Dietéticas para Conter a Hipertensão/estatística & dados numéricos , Método Duplo-Cego , Feminino , Humanos , Hiperlipidemias/sangue , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Triglicerídeos/sangue
7.
Clin Nutr ; 40(4): 1871-1878, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33131908

RESUMO

BACKGROUND & AIMS: Plasma ceramides have been identified as novel risk factors for metabolic and cardiovascular diseases. We aimed to evaluate the effects of dietary anthocyanins on plasma ceramides and to disentangle whether the alterations in ceramides could be related with those in other cardiometabolic risk factors in the dyslipidemia. METHODS: In a randomized double-blinded placebo-controlled trial, 176 eligible dyslipidemia subjects were randomly assigned into four groups receiving placebo, 40, 80, or 320 mg/day anthocyanins, respectively for 12 weeks. RESULTS: A total of 169 subjects completed the study. After 12-week intervention, dietary anthocyanins dose-dependently reduced plasma concentrations of all six ceramide species in the dyslipidemia subjects (all Ptrend values < 0.05). Specifically, 320 mg/day anthocyanins effectively lowered plasma N-palmitoylsphingosine (Cer 16:0, mean change: -28.3 ± 41.2 versus 2.9 ± 38.2, nmol/L, P = 0.018) and N-tetracosanoylsphingosine (Cer 24:0, mean change: -157.1 ± 493.9 versus 10.7 ± 439.9, nmol/L, P = 0.002) compared with the placebo. The declines in plasma Cer 16:0 and Cer 24:0 were significantly correlated with the decreases in plasma non-high-density lipoprotein cholesterol (nonHDL-C, Spearman's r = 0.32, P = 0.040 for Cer 16:0; Spearman's r = 0.35, P = 0.026 for Cer 24:0), apolipoprotein B (Spearman's r = 0.33, P = 0.031 for Cer 16:0; Spearman's r = 0.48, P = 0.002 for Cer 24:0), and total cholesterol (Spearman's r = 0.34, P = 0.026 for Cer 16:0; Spearman's r = 0.31, P = 0.042 for Cer 24:0) after 12-week 320 mg/day anthocyanin administration. Besides, we found that anthocyanins at 320 mg/day also markedly enhanced cholesterol efflux capacity in the dyslipidemia, the changes of which were positively associated with the reductions in Cer 16:0 (Spearman's r = 0.42, P = 0.006) independent of HDL-C and apolipoprotein A-I. CONCLUSIONS: Reductions in plasma Cer 16:0 and Cer 18:0 after 12-week anthocyanin intervention were dose-dependently associated with improvements in plasma lipids and cholesterol efflux capacity in the dyslipidemia. CLINICAL TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov with the identifier No. NCT03415503.


Assuntos
Antocianinas/farmacologia , Ceramidas/sangue , Colesterol/sangue , Suplementos Nutricionais , Dislipidemias/tratamento farmacológico , Lipídeos/sangue , Adulto , Idoso , Antocianinas/sangue , China , Relação Dose-Resposta a Droga , Método Duplo-Cego , Dislipidemias/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Zhongguo Gu Shang ; 29(8): 764-766, 2016 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-29282939

RESUMO

OBJECTIVE: To summarize clinical result of the modified posterior approach for the treatment of the mid and distal segment humeral fractures. METHODS: Between January 2006 and December 2010, 26 patients with the mid and distal segment humeral fractures were treated with the open reduction and plate fixation by the modified posterior approach including 17 males and 9 females with an average of (37.1±1.5) years old ranging from 24 to 50 years old. The time from humeral fractures to operation were from 8 hours to 6 days with an average of (3.3±0.6) d. The elbow function were assessed by Morrey-Bryan. RESULTS: There was no procedure related complications occurred. No neurologic injury and wound infection after operation occurred. All patients were followed up from 22 to 48 months with an average of (30.1±1.6) months. The humeral fractures were confirmed healing. The clinical results of Morrey and Bryan were excellent in 19 cases (94.6±1.8), good in 7 cases (86.5±1.2). CONCLUSIONS: The modified posterior approach avoided injury of triceps muscle and improved postoperative triceps function. The technique may be particularly useful in the treatment of the mid and distal segment humeral fractures.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/métodos , Fraturas do Úmero/cirurgia , Adulto , Articulação do Cotovelo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético , Resultado do Tratamento
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