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1.
Phys Rev Lett ; 132(5): 056101, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38364152

RESUMO

The slow transition from an out-of-equilibrium glass towards a supercooled liquid is a complex relaxation phenomenon. In this Letter, we study the correlation between mechanical relaxation and equilibration kinetics in a Pd_{20}Pt_{20}Cu_{20}Ni_{20}P_{20} high-entropy metallic glass. The evolution of stress relaxation with aging time was obtained with an unprecedented detail, allowing us to pinpoint new interesting features. The long structural relaxation towards equilibrium contains a wide distribution of activation energies, instead of being just associated to the ß relaxation as commonly accepted. The stress relaxation time can be correlated with the equilibration rate and we observe a decrease of microstructural heterogeneity which contrasts with an increase of dynamic heterogeneity. These results significantly enhance our insight of the interplay between relaxation dynamics and thermodynamics in metallic glasses.

2.
Clin Radiol ; 79(6): e842-e853, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582632

RESUMO

AIM: We design a feasibility study to obtain a set of metabolic-hemodynamic habitats for tackling tumor spatial metabolic patterns with hemodynamic information. MATERIALS AND METHODS: Preoperative data from 69 high-grade gliomas (HGG) patients with subsequent histologic confirmation of HGG were prospectively collected (January 2016 to March 2020) after concurrent chemoradiotherapy (CCRT). Four vascular habitats were automatically segmented by multiparametric magnetic resonance imaging (MRI). The metabolic information, either at enhancing or edema tumor regions, was obtained by two neuroradiologists. The relative habitat volumes were used for weight estimation procedures for computing the coefficients of a linear regression model using weighted least squares (WLS) for metabolite semiquantifications (i.e. the Cho/NAA ratio and the Cho/Cr ratio) at vascular habitats. Multivariate Cox proportional hazard regression analyses are used to obtain the odds ratio (OR) and develop a nomogram using weighted estimators corresponding to each covariate derived from Cox regression coefficients. RESULTS: There was a strongly correlation between perfusion indexes and the Cho/Cr ratio (rCBV, r=0.71) or Cho/NAA ratio (rCBV, r=0.66) at high-angiogenic enhancing tumor habitats (HAT) habitat. Compared isocitrate dehydrogenase (IDH) mutation to their wild type, the IDH wild type had significantly decreased Cho/Cr ratio (IDH mutation: Cho/Cr ratio = 2.44 ± 0.33, IDH wildtype: Cho/Cr ratio = 2.66 ± 0.36, p=0.02) and Cho/NAA ratio (IDH mutation: Cho/Cr ratio = 4.59 ± 0.61, IDH wildtype: Cho/Cr ratio = 4.99 ± 0.66, p=0.022) at the HAT. The C-index for the median progression-free survival (PFS) prediction was 0.769 for the Cho/NAA nomogram and 0.747 for the Cho/Cr nomogram through 1000 bootstrapping validation. CONCLUSIONS: Our findings suggest that spatial metabolism combined with hemodynamic heterogeneity is associated with individual PFS to HGG patients post-CCRT.


Assuntos
Neoplasias Encefálicas , Estudos de Viabilidade , Glioma , Hemodinâmica , Intervalo Livre de Progressão , Humanos , Glioma/diagnóstico por imagem , Glioma/patologia , Glioma/terapia , Feminino , Masculino , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Pessoa de Meia-Idade , Hemodinâmica/fisiologia , Adulto , Estudos Prospectivos , Idoso , Imageamento por Ressonância Magnética Multiparamétrica/métodos
3.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(7): 647-653, 2024 Jul 12.
Artigo em Zh | MEDLINE | ID: mdl-38955750

RESUMO

Objective: To investigate the relationship between arousal threshold (ArTH) and hypertension in patients with obstructive sleep apnea hypopnea syndrome (OSA). Methods: This study recruited 648 patients diagnosed with OSA at the Sleep Center of the Second Affiliated Hospital of Soochow University from January 2020 to August 2021, including 569 males and 79 females, aged 42(35,52) years. The basic demographic information and clinical data of all patients were collected, including blood pressure measurement, and relevant questionnaire scores, and nocturnal polysomnography (PSG) parameters. A clinical predictive model based on sleep apnea hypopnea index (AHI), lowest pulse oxygen saturation (LSpaO2) and hypopnea ratio (FHypopneas) was used to access the arousal threshold of OSA patients. Patients were divided into OSA group and OSA with hypertension group according to whether they were combined with hypertension. The differences in the above indexes between the two groups were analyzed to explore the relationship between arousal threshold and hypertension in OSA patients, using a binary logistic stepwise regression analysis. Results: A total of 648 OSA patients were enrolled, including 415 in the OSA with hypertension group and 233 in the OSA group. Compared with OSA group, OSA with hypertension group had older age, higher body mass index (BMI), higher blood pressure at bedtime and at awakening, higher AHI and lower proportion of hypopnea (all P<0.05). There were no significant differences between other general data and PSG parameters (all P>0.05). The proportion of patients with low arousal threshold (AHI<30 events per hour, LSpO2>82.5%, Fhypopneas>58.3%) in OSA with hypertension group was lower, and the proportion of phenotypic patients with low arousal threshold was significantly lower (30.1% vs. 52.4% P<0.001). Binary logistic stepwise regression analysis showed that the high arousal threshold (OR=1.930, 95%CI:1.326-2.808, P=0.001) was an independent risk factor for OSA complicated with hypertension. Conclusion: The arousal threshold is associated with the development of hypertension in OSA patients, and OSA patients with a high arousal threshold have a higher risk of developing hypertension.


Assuntos
Nível de Alerta , Hipertensão , Polissonografia , Apneia Obstrutiva do Sono , Humanos , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/complicações , Feminino , Masculino , Pessoa de Meia-Idade , Hipertensão/fisiopatologia , Hipertensão/complicações , Adulto , Fatores de Risco , Pressão Sanguínea , Modelos Logísticos , Saturação de Oxigênio , Inquéritos e Questionários
5.
Nan Fang Yi Ke Da Xue Xue Bao ; 44(1): 9-16, 2024 Jan 20.
Artigo em Zh | MEDLINE | ID: mdl-38293971

RESUMO

OBJECTIVE: To investigate the role of RNA-binding motif protein X-linked (RBMX) in regulating the proliferation, migration, invasion and glycolysis in human bladder cancer cells. METHODS: A lentivirus vectors system and RNA interference technique were used to construct bladder cancer 1376 and UC-3 cell models with RBMX overexpression and knockdown, respectively, and successful cell modeling was verified using RT-qPCR and Western blotting. Proliferation and colony forming ability of the cells were evaluated using EdU assay and colony-forming assay, and cell migration and invasion abilities were determined using Transwell experiment. The expressions of glycolysis-related proteins M1 pyruvate kinase (PKM1) and M2 pyruvate kinase (PKM2) were detected using Western blotting. The effects of RBMX overexpression and knockdown on glycolysis in the bladder cancer cells were assessed using glucose and lactic acid detection kits. RESULTS: RT-qPCR and Western blotting confirmed successful construction of 1376 and UC-3 cell models with RBMX overexpression and knockdown. RBMX overexpression significantly inhibited the proliferation, clone formation, migration and invasion of bladder cancer cells, while RBMX knockdown produced the opposite effects. Western blotting results showed that RBMX overexpression increased the expression of PKM1 and decreased the expression of PKM2, while RBMX knockdown produced the opposite effects. Glucose consumption and lactate production levels were significantly lowered in the cells with RBMX overexpression (P < 0.05) but increased significantly following RBMX knockdown (P < 0.05). CONCLUSION: RBMX overexpression inhibits bladder cancer progression and lowers glycolysis level in bladder cancer cells by downregulating PKM2 expression, suggesting the potential of RBMX as a molecular target for diagnosis and treatment of bladder cancer.


Assuntos
Piruvato Quinase , Neoplasias da Bexiga Urinária , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Glucose/farmacologia , Glicólise , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Neoplasias da Bexiga Urinária/genética
6.
Nat Commun ; 15(1): 6782, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39117648

RESUMO

Intermetallic alloys have traditionally been characterized by their inherent brittleness due to their lack of sufficient slip systems and absence of strain hardening. However, here we developed a single-phase B2 high-entropy intermetallic alloy that is both strong and plastic. Unlike conventional intermetallics, this high-entropy alloy features a highly distorted crystalline lattice with complex chemical order, leading to multiple slip systems and high flow stress. In addition, the alloy exhibits a dynamic hardening mechanism triggered by dislocation gliding that preserves its strength across a wide range of temperatures. As a result, this high-entropy intermetallic circumvents precipitous thermal softening, with extensive plastic flows even at high homologous temperatures, outperforming a variety of both body-centered cubic and B2 alloys. These findings reveal a promising direction for the development of intermetallic alloys with broad engineering applications.

7.
Braz. j. med. biol. res ; 48(2): 167-173, 02/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-735851

RESUMO

High levels of low-density lipoprotein cholesterol (LDL-C) enhance platelet activation, whereas high levels of high-density lipoprotein cholesterol (HDL-C) exert a cardioprotective effect. However, the effects on platelet activation of high levels of LDL-C combined with low levels of HDL-C (HLC) have not yet been reported. We aimed to evaluate the platelet activation marker of HLC patients and investigate the antiplatelet effect of atorvastatin on this population. Forty-eight patients with high levels of LDL-C were enrolled. Among these, 23 had HLC and the other 25 had high levels of LDL-C combined with normal levels of HDL-C (HNC). A total of 35 normocholesterolemic (NOMC) volunteers were included as controls. Whole blood flow cytometry and platelet aggregation measurements were performed on all participants to detect the following platelet activation markers: CD62p (P-selectin), PAC-1 (GPIIb/IIIa), and maximal platelet aggregation (MPAG). A daily dose of 20 mg atorvastatin was administered to patients with high levels of LDL-C, and the above assessments were obtained at baseline and after 1 and 2 months of treatment. The expression of platelets CD62p and PAC-1 was increased in HNC patients compared to NOMC volunteers (P<0.01 and P<0.05). Furthermore, the surface expression of platelets CD62p and PAC-1 was greater among HLC patients than among HNC patients (P<0.01 and P<0.05). Although the expression of CD62p and PAC-1 decreased significantly after atorvastatin treatment, it remained higher in the HLC group than in the HNC group (P<0.05 and P=0.116). The reduction of HDL-C further increased platelet activation in patients with high levels of LDL-C. Platelet activation remained higher among HLC patients regardless of atorvastatin treatment.


Assuntos
Adolescente , Criança , Feminino , Humanos , Masculino , Logro , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Atenção/fisiologia , Análise de Variância , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Estudos de Coortes , Escolaridade , Escalas de Graduação Psiquiátrica , Sensibilidade e Especificidade
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