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1.
Phys Rev E ; 109(5-1): 054124, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38907442

RESUMEN

Glass formers are, in general, classified as strong or fragile depending on whether their relaxation rates follow Arrhenius or super-Arrhenius temperature dependence. There are, however, notable exceptions, such as water, which exhibit a fragile-to-strong (FTS) transition and behave as fragile and strong, respectively, at high and low temperatures. In this work, the FTS transition is studied using a distinguishable-particle lattice model previously demonstrated to be capable of simulating both strong and fragile glasses [C.-S. Lee, M. Lulli, L.-H. Zhang, H.-Y. Deng, and C.-H. Lam, Phys. Rev. Lett. 125, 265703 (2020)0031-900710.1103/PhysRevLett.125.265703]. Starting with a bimodal pair-interaction distribution appropriate for fragile glasses, we show that by narrowing down the energy dispersion in the low-energy component of the distribution, a FTS transition is observed. The transition occurs at a temperature at which the stretching exponent of the relaxation is minimized, in agreement with previous molecular dynamics simulations.

2.
Int J Biol Sci ; 20(4): 1529-1546, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38385073

RESUMEN

Myeloid-derived suppressor cells (MDSCs) expand during sepsis and contribute to the development of persistent inflammation-immunosuppression-catabolism syndrome. However, the underlying mechanism remains unclear. Exploring the mechanisms of MDSCs generation may provide therapeutic targets for improving immune status in sepsis. Here, a sepsis mouse model is established by cecal ligation and perforation. Bone marrow cells at different sepsis time points are harvested to detect the proportion of MDSCs and search for differentially expressed genes by RNA-sequence. In lethal models of sepsis, polymorphonuclear-MDSCs (PMN-MDSCs) decrease in early but increase and become activated in late sepsis, which is contrary to the expression of metastasis-associated lung adenocarcinoma transcript 1 (Malat1). In vivo, Malat1 inhibitor significantly increases the mortality in mice with late sepsis. And in vitro, Malat1 down-regulation increases the proportion of PMN-MDSCs and enhanced its immunosuppressive ability. Mechanistically, Malat1 limits the differentiation of PMN-MDSCs by accelerating the degradation of phosphorylated STAT3. Furthermore, Stattic, an inhibitor of STAT3 phosphorylation, improves the survival of septic mice by inhibiting PMN-MDSCs. Overall, the study identifies a novel insight into the mechanism of sepsis-induced MDSCs and provides more evidence for targeting MDSCs in the treatment of sepsis.


Asunto(s)
Células Supresoras de Origen Mieloide , Sepsis , Animales , Ratones , Modelos Animales de Enfermedad , Terapia de Inmunosupresión , Células Supresoras de Origen Mieloide/metabolismo , Sepsis/metabolismo
3.
Front Immunol ; 14: 1172892, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37614234

RESUMEN

Background: Degradation of the endothelial glycocalyx is critical for sepsis-associated lung injury and pulmonary vascular permeability. We investigated whether sulodexide, a precursor for the synthesis of glycosaminoglycans, plays a biological role in glycocalyx remodeling and improves endothelial barrier dysfunction in sepsis. Methods: The number of children with septic shock that were admitted to the PICU at Children's Hospital of Fudan University who enrolled in the study was 28. On days one and three after enrollment, venous blood samples were collected, and heparan sulfate, and syndecan-1 (SDC1) were assayed in the plasma. We established a cell model of glycocalyx shedding by heparinase III and induced sepsis in a mouse model via lipopolysaccharide (LPS) injection and cecal ligation and puncture (CLP). Sulodexide was administrated to prevent endothelial glycocalyx damage. Endothelial barrier function and expression of endothelial-related proteins were determined using permeability, western blot and immunofluorescent staining. The survival rate, histopathology evaluation of lungs and wet-to-dry lung weight ratio were also evaluated. Results: We found that circulating SDC1 levels were persistently upregulated in the non-alive group on days 1 and 3 and were positively correlated with IL-6 levels. Receiver operating characteristic curve analysis showed that SDC1 could distinguish patients with mortality. We showed that SDC1-shedding caused endothelial permeability in the presence of heparinase III and sepsis conditions. Mechanistically, sulodexide (30 LSU/mL) administration markedly inhibited SDC1 shedding and prevented endothelial permeability with zonula occludens-1 (ZO-1) upregulation via NF-κB/ZO-1 pathway. In mice with LPS and CLP-induced sepsis, sulodexide (40 mg/kg) administration decreased the plasma levels of SDC1 and increased survival rate. Additionally, sulodexide alleviated lung injury and restored endothelial glycocalyx damage. Conlusions: In conclusion, our data suggest that SDC1 predicts prognosis in children with septic shock and sulodexide may have therapeutic potential for the treatment of sepsis-associated endothelial dysfunction.


Asunto(s)
Lesión Pulmonar , Sepsis , Choque Séptico , Animales , Ratones , Células Endoteliales , Permeabilidad Capilar , Glicocálix , Lipopolisacáridos , Sepsis/tratamiento farmacológico , Glicosaminoglicanos/farmacología , Peso Corporal
4.
J Phys Chem B ; 127(15): 3452-3462, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37042489

RESUMEN

Water has anomalous thermodynamic and kinetic properties distinct from ordinary liquids. The famous examples are the density maximum at 4 °C and the viscosity decrease upon pressurization. The presence of the second critical point has been considered to be responsible for these anomalies since its discovery in ST2 water. Recently, its existence has been confirmed firmly in TIP4P/2005, which is one of the most successful classical models of water, by Debenedetti et al. [Debenedetti et al. Science 2020, 369, 289]. Here, we study the water structure and thermodynamic and dynamic quantities in a wide temperature (T)-pressure (P) range, including the vicinity of the second critical point, by extensive molecular dynamics simulation of this water model. We reveal that a hierarchical two-state model with the cooperative formation of water tetrahedral structures via hydrogen bonding can describe the T, P-dependences of structure, thermodynamic and kinetic anomalies, and criticality of TIP4P/2005 water in a unified manner. TIP4P/2005 water shows very similar behaviors to real water in all these aspects, suggesting a possible existence of the second critical point in the water. Our physical description based on the two order parameters, the density and the fraction of locally favored tetrahedral structures, indicates that the latter is the relevant order parameter for the second critical point, which is supported by the analysis of the critical fluctuations. The different nature of the density and the fraction of tetrahedral arrangements, conserved and nonconserved, may be key to unambiguously identifying the relevant order parameter.

5.
Traffic Inj Prev ; 24(5): 402-408, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37052988

RESUMEN

OBJECTIVE: Traffic accidents are mainly caused by driver-to-pedestrian collisions or driver-to-driver collisions. Prosocial driving behavior indicates that drivers exhibit altruistic behavior toward other drivers on roads. Yielding behavior demonstrates that drivers grant the right of passage to pedestrians at unsignalized crossings, while yielding attitude presents the subjective emotional and cognitive inclination to yield to pedestrians at unsignalized crossings. This study aims to explore the effect of altruism and drivers' perceived stress on prosocial driving behavior, yielding behavior, and yielding attitude. In addition, we endeavor to explore the effect of stress on prosocial driving behavior exhibiting an inverted "U-type" curve as Yerkes-Dodson's law suggests and test the moderating role of perceived stress on altruism and prosocial driving behavior/yielding behavior/yielding attitude. METHODS: Using a survey method, we asked 454 participants to complete an altruism scale from the IPIT measuring altruism, a Perceived Stress Scale-10 measuring drivers' perceived stress, a prosocial driving scale from the PADI measuring prosocial driving behavior, and items on yielding behavior and yielding attitude. Then, a correlational matrix, a hierarchical multiple nonparametric regression analysis, and a moderating analysis of perceived stress were employed in sequence to reach our objective. RESULTS: The hierarchical multiple nonparametric regression analysis showed that altruism positively predicts yielding attitude (F = 41.56, p < 0.001), yielding behavior (z = 8.46, p < 0.001, odds ratio = 4.90) and prosocial driving behavior (F = 110.66, p < 0.001), but stress predicts only prosocial driving behavior (F = 7.63, p < 0.001), not yielding attitude (F = 0.51, p > 0.05) or yielding behavior (z = 0.12, p > 0.05), which exhibits an inverted "U-type" curve. Moderating analyses showed that stress only moderates the relationship between altruism and yielding attitude (B = -0.24, t = -2.62, p < 0.01). CONCLUSIONS: Altruism is positively related to prosocial driving behavior, yielding behavior, and yielding attitude. Stress influences prosocial driving behavior only and exhibits an inverted "U-type" curve. Stress does not directly influence the yielding behavior. Instead, stress moderates the relationship between altruism and yielding attitude only and may further increase the possibility of yielding behavior.


Asunto(s)
Accidentes de Tránsito , Conducción de Automóvil , Humanos , Altruismo , Seguridad , Actitud
6.
J Clin Med ; 11(23)2022 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-36498566

RESUMEN

AIM: The ERAS protocol consists of multiple items that aim to improve the outcomes of patients receiving surgery. Adhering to the protocol is difficult. We wondered whether surgeons practicing the ERAS protocol in a group would improve patient outcomes. Methods: All patients who underwent colorectal resection for benign disease or malignancy from November 2017 to December 2018 were collected and reviewed retrospectively. According to the physician's ward round strategy, the patients were categorized into two groups, either by solo practice or group practice. Results: This study enrolled 724 patients and divided them into two groups according to the practice method: group practice (n = 256) and solo practice (n = 468). The group practice cohort had less postoperative morbidity (14.0% vs. 21.4%, p = 0.048) and shorter postoperative hospital stays (mean: 6.6 ± 3.2 vs. 8.6 ± 5.5, p < 0.05) than the solo practice cohort. Group practice (p < 0.001), natural orifice specimen extraction (NOSE) procedure (p < 0.001), and blood loss >50 mL (p = 0.039) significantly affected discharge within 5 days postoperatively in multivariate analyses. Conclusions: Group practice based on a modified ERAS protocol shortens postoperative hospital stays with fewer morbidities compared with solo practice in which patients receive elective minimally invasive colorectal surgery.

7.
Accid Anal Prev ; 177: 106824, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36063570

RESUMEN

Drivers with a high level of trait anger feel more intensity of anger on road, contributing to more risky driving behavior and further increasing the probability of collisions. It seems that trait anger directly correlates with risky driving behavior, but how it works in detail remains unknown and previous research indicated executive function and hazard cognition may play a mediation role in it. Our research aims to explore the relationship among these variables and test if there is a multiple mediation model. We sampled 302 valid participants and used online questionnaires, containing trait anger scale (TAS), executive function index (EFI), hazard cognition scale (HCS; representing attitudes towards risky driving behavior), driver behavior questionnaire (DBQ), and self-reported traffic violations (e.g., accidents, penalty points, fines). Hierarchical multiple linear regression of DBQ results show trait anger is a medium but statistically significant predictor of risky driving behavior and drivers' attitude towards risky situations can significantly predict risky driving behavior at medium effect. But risky driving behavior cannot be predicted by executive function. Interestingly, opposing to prior research, zero-inflated Poisson regression analysis of self-reported traffic violations suggests trait anger negatively predicts accidents and fines in the zero-inflation model, and hazard cognition negatively predicts penalty points. Notably, the executive function negatively predicts penalty points and fines in the count model, which confirms our hypothetical direction. They all represent a small effect size in this nonlinear regression model. Path analysis suggested that trait anger influences risky driving behavior through executive function, and hazard cognition both separately and jointly. This study provides a theoretical framework for the transaction model of aggressive driving behavior and offers some possible interventions toward the effect of trait anger on risky driving behavior.


Asunto(s)
Accidentes de Tránsito , Conducción de Automóvil , Ira , Cognición , Función Ejecutiva , Humanos , Asunción de Riesgos , Encuestas y Cuestionarios
8.
J Healthc Eng ; 2022: 5120556, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35299681

RESUMEN

A multiuser motion-monitoring system based on MEMS is proposed for fitness movement, it is used to monitor the three important parameters of movement type, movement times, and movement cycle in the body movement and supports the simultaneous use of multiple users. The specific content of the method: (1) In terms of system design, a motion-monitoring system framework based on the Internet of things is proposed considering the motion-monitoring scene oriented to intelligent fitness. (2) In the aspect of algorithm, the relevant research of motion pattern recognition and cycle calculation method is carried out. For action pattern recognition, SVM-based algorithm to adapt to different computing capabilities of the scene is applied. (3) Experiments on 7 kinds of actions show that the proposed deep neural network has a good learning effect on small datasets, the recognition accuracy of the proposed deep neural network reaches 97.61%, and the recognition accuracy of SVM also reaches over 96%. In the 50 times of operation cycle calculation experiments, the frequency statistics algorithm has reached 100% of the calculation accuracy, and the calculation results of the operation cycle are close to the real value, which proves the validity of the method of cycle calculation. The experiment proves that the zero-crossing detection and wavelet analysis methods have a good overall effect and can accurately count and calculate the period when the number of actions is more, improve fitness efficiency, and provide guarantee for human health.


Asunto(s)
Internet de las Cosas , Algoritmos , Arritmias Cardíacas , Electrocardiografía , Humanos , Internet , Movimiento , Redes Neurales de la Computación
9.
Sensors (Basel) ; 18(9)2018 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-30181441

RESUMEN

To detect perimeter intrusion accurately and quickly, a stream computing technology was used to improve real-time data processing in perimeter intrusion detection systems. Based on the traditional density-based spatial clustering of applications with noise (T-DBSCAN) algorithm, which depends on manual adjustments of neighborhood parameters, an adaptive parameters DBSCAN (AP-DBSCAN) method that can achieve unsupervised calculations was proposed. The proposed AP-DBSCAN method was implemented on a Spark Streaming platform to deal with the problems of data stream collection and real-time analysis, as well as judging and identifying the different types of intrusion. A number of sensing and processing experiments were finished and the experimental data indicated that the proposed AP-DBSCAN method on the Spark Streaming platform exhibited a fine calibration capacity for the adaptive parameters and the same accuracy as the T-DBSCAN method without the artificial setting of neighborhood parameters, in addition to achieving good performances in the perimeter intrusion detection systems.

10.
Plant Mol Biol ; 83(3): 219-33, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23748738

RESUMEN

Aquaporins (AQPs) are multifunctional membrane channels and facilitate the transport of water across plant cell membranes. Among the plant AQPs, plasma membrane intrinsic proteins (PIPs), which cluster in two phylogenetic groups (PIP1 and PIP2), play a key role in plant growth. Our previous work has indicated that RhPIP2;1, a member of PIP2, is involved in ethylene-regulated cell expansion of rose petals. However, whether PIP1s also play a role in petal expansion is still unclear. Here, we identified RhPIP1;1, a PIP1 subfamily member, from 18 PIPs assemble transcripts in rose microarray database responsive to ethylene. RhPIP1;1 was rapidly and significantly down-regulated by ethylene treatment. RhETRs-silencing also clearly decreased the expression of RhPIP1;1 in rose petals. The activity of the RhPIP1;1 promoter was repressed by ethylene in rosettes and roots of Arabidopsis. RhPIP1;1 is mainly localized on endoplasmic reticulum and plasma membrane. We demonstrated that RhPIP1;1-silencing significantly inhibited the expansion of petals with decreased petal size and cell area, as well as reduced fresh weight when compared to controls. Expression of RhPIP1;1 in Xenopus oocytes indicated that RhPIP1;1 was inactive in terms of water transport, while coexpression of RhPIP1;1 with the functional RhPIP2;1 led to a significant increase in plasma membrane permeability. Yeast growth, ß-Galactosidase activity, bimolecular fluorescence complementation, and colocalization assay proved existence of the interaction between RhPIP1;1 and RhPIP2;1. We argue that RhPIP1;1 plays an important role in ethylene-regulated petal cell expansion, at least partially through the interaction with RhPIP2;1.


Asunto(s)
Acuaporinas/fisiología , Etilenos/metabolismo , Flores , Rosa/fisiología , Animales , Acuaporinas/genética , Regulación hacia Abajo , Silenciador del Gen , Genes de Plantas , Regiones Promotoras Genéticas , Rosa/genética , Fracciones Subcelulares/metabolismo , Xenopus
11.
J Chromatogr Sci ; 40(4): 187-90, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12004936

RESUMEN

The electroosmotic flow (EOF) is measured as a function of tetradecyltrimethylammonium bromide (TTAB) concentration and is shown to have distinct zones that are pH dependent. The data is correlated with previously proposed surface structures ranging from unimolecular adsorption to hemimicelles and micelles of TTAB adsorbed on the hydrated fused silica. A plot of the TTAB concentration at zero EOF versus pH shows that the zero point of charge (zpc) is pH dependent and that a linear extrapolation of the data intercepts close to the pH value for the zpc of a fused-silica surface. This shows that different surface properties at different pH values at any given TTAB concentration are generally dealt with. Therefore, these pH-dependent structures of the fused-silica surface have to be taken into account while studying these phenomena.

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