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1.
Brain Behav Immun ; 117: 80-99, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38190982

RESUMEN

Emerging studies have demonstrated spinal microglia play a critical role in central sensitization and contribute to chronic pain. Although several mediators that contribute to microglia activation have been identified, the mechanism of microglia activation and its functionally diversified mechanisms in pathological pain are still unclear. Here we report that injured sensory neurons-derived Galectin-3 (Gal3) activates and reprograms microglia in the spinal dorsal horn (SDH) and contributes to neuropathic pain. Firstly, Gal3 is predominantly expressed in the isolectin B4 (IB4)-positive non-peptidergic sensory neurons and significantly up-regulated in dorsal root ganglion (DRG) neurons and primary afferent terminals in SDH in the partial sciatic nerve ligation (pSNL)-induced neuropathic pain model. Gal3 knockout (Gal3 KO) mice showed a significant decrease in mechanical allodynia and Gal3 inhibitor TD-139 produced a significant anti-allodynia effect in the pSNL model. Furthermore, pSNL-induced microgliosis was compromised in Gal3 KO mice. Additionally, intrathecal injection of Gal3 produces remarkable mechanical allodynia by direct activation of microglia, which have enhanced inflammatory responses with TNF-α and IL-1ß up-regulation. Thirdly, using single-nuclear RNA sequencing (snRNA-seq), we identified that Gal3 targets microglia and induces reprogramming of microglia, which may contribute to neuropathic pain establishment. Finally, Gal3 enhances excitatory synaptic transmission in excitatory neurons in the SDH via microglia activation. Our findings reveal that injured sensory neurons-derived Gal3 programs microglia in the SDH and contribute to neuropathic pain.


Asunto(s)
Galectina 3 , Neuralgia , Animales , Ratones , Galectina 3/genética , Hiperalgesia , Microglía , Células Receptoras Sensoriales
2.
J Org Chem ; 88(22): 15717-15725, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37885137

RESUMEN

A binary catalytic system comprising tetrahydroxydiboron and tetrabutylammonium iodide (TBAI) was used to catalyze the cycloaddition of carbon dioxide (CO2) with epoxides. The tetrahydroxydiboron catalyst (9 mol %), in combination with the use of TBAI (13.5 mol %) as a nucleophile, is capable of catalyzing the cycloaddition of CO2 with various terminal epoxides under room temperature and a CO2 balloon. In addition, a range of internal epoxides, including sterically hindered bicyclic epoxides and vegetable oil-based epoxides, were suitable for the catalytic system, affording a series of cyclic carbonates in moderate to high yields. The tetrahydroxydiboron/TBAI cooperative catalytic mechanism was elucidated using Fourier transform infrared spectroscopy, nuclear magnetic resonance, and electrospray ionization-high-resolution mass spectrometry. Results reveal that the tetrahydroxydiboron catalyst exhibits dual effects, activating both CO2 and epoxides; initially, it underwent the insertion of CO2 to form a boron-CO2 adduct and subsequently activated the epoxides through interaction of the B-O bond.

3.
Phys Chem Chem Phys ; 25(36): 24332-24341, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37670676

RESUMEN

As a novel type of anisotropic two-dimensional material, extensive attention has been paid to the thermoelectric (TE) properties of FeOCl-type monolayers, such as Al2X2Se2 (X = Cl, Br, I), Sc2I2S2, and Ir2Cl2O2. Recently, theoretical works based on first-principles calculations have been powerful driving forces in field of TE research. In this work, we perform an investigation into the TE properties of Sc2X2Se2 (X = Cl, Br, I) monolayers based on density functional theory (DFT). A study on the stability, including AIMD simulation and phonon calculation, shows the stable structure of Sc2Cl2Se2, Sc2Br2Se2, and Sc2I2Se2 monolayers. Additionally, the electronic and thermal transport properties of Sc2X2Se2 monolayers are anisotropic along the x and y directions. Moreover, the combination of excellent Seebeck coefficient and ultralow lattice thermal conductivity contributes to outstanding ZT values, and the ZT values follow the order: Sc2I2Se2 > Sc2Br2Se2 > Sc2Cl2Se2. At 300 K, we obtained maximum ZT of 0.34, 0.77, and 1.97 for Sc2Cl2Se2, Sc2Br2Se2, and Sc2I2Se2, respectively, by n-type doping in the x direction. These results demonstrate that monolayer Sc2X2Se2 (X = Cl, Br, I) materials are promising thermoelectric materials, Sc2I2Se2 has more desirable properties along the x direction, and n-type doping can significantly enhance the ZT values. Our work lays a foundation for exploring the TE transport properties of FeOCl-type monolayers.

4.
Chaos ; 33(9)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37748483

RESUMEN

The existence of a corrugated surface is of great importance and ubiquity in biological systems, exhibiting diverse dynamic behaviors. However, it has remained unclear whether such rough surface leads to the current reversal in fractional hydrodynamic memory. We investigate the transport of a particle within a rough potential under external forces in a subdiffusive media with fractional hydrodynamic memory. The results demonstrate that roughness induces current reversal and a transition from no transport to transport. These phenomena are analyzed through the subdiffusion, Peclet number, useful work, input power, and thermodynamic efficiency. The analysis reveals that transport results from energy conversion, wherein time-dependent periodic force is partially converted into mechanical energy to drive transport against load, and partially dissipated through environmental absorption. In addition, the findings indicate that the size and shape of ratchet tune the occurrence and disappearance of the current reversal, and control the number of times of the current reversal occurring. Furthermore, we find that temperature, friction, and load tune transport, resonant-like activity, and enhanced stability of the system, as evidenced by thermodynamic efficiency. These findings may have implications for understanding dynamics in biological systems and may be relevant for applications involving molecular devices for particle separation at the mesoscopic scale.

5.
Inorg Chem ; 60(1): 167-174, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33326743

RESUMEN

Anionic metal-organic frameworks (MOFs) have attracted increasing attention due to the enhanced electrostatic interactions between their anionic frameworks and counter-ionic guests. Owing to these special host-guest interactions, anionic MOFs are beginning to have a large impact in the field of absorption and separation of ionic molecules and selective sensing of metal ions. Herein, two mesoporous anionic metal-organic frameworks, namely, [(CH3)2NH2]6[In6(OX)6(TCA)4]·solvents (JOU-11) and [(CH3)2NH2]6[In6(OX)6(TCPA)4]·solvents (JOU-12) (H3TCA = tricarboxytriphenylamine; H3TCPA = tris((4-carboxyl)phenylduryl)amine; OX = oxalate), have been synthesized by using wheel-type [In6(OX)6(COO)12]6- as building blocks. Structural analyses show that JOU-11 and JOU-12 show isoreticular three-dimensional frameworks with pyr topology. Due to their anionic frameworks and tunable pore window sizes, both compounds can be exploited for absorbing and separating cationic organic dyes. In addition, JOU-11 can be developed as a fluorescence "turn-off" sensor for selectively sensing Fe3+, whereas JOU-12 can be used for fluorescence "turn-on" sensing of Cu2+ and Co2+ ions.

6.
Chaos ; 30(5): 053115, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32491875

RESUMEN

We study the transport phenomena of an inertial Brownian particle in a symmetric potential with periodicity, which is driven by an external time-periodic force and an external constant bias for both cases of the deterministic dynamics and the existence of friction coefficient fluctuations. For the deterministic case, it is shown that for suitable parameters, the existence of certain appropriate friction coefficients can enhance the transport of the particle, which may be interpreted as the negative friction coefficient; additionally, there coexist absolute, differential negative, and giant positive mobilities with increasing friction coefficients in the system. We analyze physical mechanisms hinted behind these findings via basins of attraction. For the existence of friction coefficient fluctuations, it is shown that the fluctuation can enhance or weaken, even eliminate these phenomena. We present the probability distribution of the particle's velocity to interpret these mobilities and the suitable parameters' regimes of these phenomena. In order to further understand the physical mechanism, we also study diffusions corresponding to these mobilities and find that for the small fluctuation, the negative friction appears, and there coexists absolute negative mobility, superdiffusion, and ballistic diffusion, whereas all of them vanish for the large fluctuation. Our findings may extensively exist in materials, including different defects, strains, the number of interfacial hydrogen bonds, the arrangements of ions, or graphite concentrations, which hints at the existence of different friction coefficients.

7.
Biochem Biophys Res Commun ; 516(3): 825-830, 2019 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-31262448

RESUMEN

(-)-menthol, a major form of menthol, is one of the most commonly used chemicals. Many studies have demonstrated that (-)-menthol produces analgesic action through peripheral mechanisms which are mainly mediated by activation of TRPM8. Moreover, intrathecal injection of menthol induces analgesia as well. However, the central actions and mechanisms of (-)-menthol remain unclear. Here, we have investigated the action of (-)-menthol on excitatory synaptic transmission in spinal lamina II layer which plays a pivotal role in modulating nociceptive transmission from the periphery by using patch-clamp technique in mice spinal cord. We found that (-)-menthol increased miniature excitatory postsynaptic current frequency. The frequency increases which (-)-menthol induced were in a dose-dependent manner (EC50: 0.1079 mM). However, neither genetic knockout nor pharmacological inhibition of TRPM8 could block (-)-menthol-induced effects entirely. Furthermore, this increase was also impaired by TRPA1 antagonist HC030031, but abolished utterly by co-application of TRPM8 and TRPA1 antagonist. Our results indicate that (-)-menthol increases the excitatory synaptic transmission by activating either TRPA1 or TRPM8 channels in spinal lamina II layer.


Asunto(s)
Potenciales Postsinápticos Excitadores/efectos de los fármacos , Mentol/farmacología , Médula Espinal/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Canal Catiónico TRPA1/genética , Canales Catiónicos TRPM/genética , Acetanilidas/farmacología , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Animales , Benzamidas/farmacología , Relación Dosis-Respuesta a Droga , Potenciales Postsinápticos Excitadores/fisiología , Regulación de la Expresión Génica , Inyecciones Espinales , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microtomía , Técnicas de Placa-Clamp , Purinas/farmacología , Médula Espinal/citología , Médula Espinal/fisiología , Transmisión Sináptica/fisiología , Canal Catiónico TRPA1/antagonistas & inhibidores , Canal Catiónico TRPA1/metabolismo , Canales Catiónicos TRPM/antagonistas & inhibidores , Canales Catiónicos TRPM/deficiencia , Tetrodotoxina/farmacología , Tiofenos/farmacología , Técnicas de Cultivo de Tejidos
8.
BMC Public Health ; 19(1): 354, 2019 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-30922287

RESUMEN

BACKGROUND: Many studies have assessed the association between consumption of red and processed meat and the risk of heart failure, but the results are not consistent. This meta-analysis aimed to comprehensively evaluate the relationship between intake of red and processed meat and the risk of heart failure. METHODS: Databases of Web of Knowledge, PubMed, and Wan Fang Med Online were retrieved up to date of August 31st, 2017. Suitable publications were identified through using the defined inclusion criteria. The summarized relative risk (RR) with the corresponding 95% confidence interval (CI) was calculated. RESULTS: Six scientific literatures were included in this study. In comparison with the lowest category, the summarized RR and 95% CI of the highest category of processed meat intake for heart failure risk was 1.23 (95% CI = 1.07-1.41, I2 = 58.9%, P = 0.045). A significant connection between processed meat intake and heart failure was identified among the Europeans (RR = 1.33, 95% CI = 1.15-1.54), but not the Americans. Yet few of essential association was found between heart failure risk and red meat intake (RR = 1.04, 95% CI = 0.96-1.12). CONCLUSIONS: Findings of this meta-analysis indicated that the highest category of processed meat intake, other than red meat intake, correlated with an increased risk of heart failure.


Asunto(s)
Dieta/efectos adversos , Insuficiencia Cardíaca/epidemiología , Productos de la Carne/efectos adversos , Carne Roja/efectos adversos , Dieta/estadística & datos numéricos , Humanos , Riesgo
9.
Ann Hum Genet ; 82(5): 265-271, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29682741

RESUMEN

The calcium-sensing receptor (CaSR) gene plays an important role in regulating the Ca2+ balance and reducing the risk for calcium stones. In this study, we evaluated the association of CaSR polymorphisms with calcium nephrolithiasis in the population of Yi nationality in Southwestern China. Biochemical variables were evaluated in 624 calcium nephrolithiasis patients and 470 age-matched healthy controls without a history of nephrolithiasis. CaSR polymorphisms rs7652589, rs1501899, rs1801725 (Ala986Ser), rs1042636 (Arg990Gly) and rs1801726 (Gln1011Glu) were investigated between the calcium nephrolithiasis patients and healthy controls, using direct sequencing. Compared with the healthy controls, serum creatinine and 24-hour urine calcium levels were significantly higher in calcium nephrolithiasis patients. Among these five polymorphisms, the genotypic and allelic frequency distributions of rs7652589 SNP was significantly associated with the risk of calcium nephrolithiasis. However, there were no genotypic or allelic distribution differences for rs1501899, rs1801725, rs1042636, and rs1801726 polymorphisms between calcium nephrolithiasis patients and healthy controls. Moreover, the association between rs7652589 SNP genotypes and the biochemical variables was not found. Our study showed that CaSR rs7652589 polymorphism had a significant effect on the risk of developing calcium nephrolithiasis in the population of Yi nationality in Southwestern China.


Asunto(s)
Pueblo Asiatico/genética , Etnicidad/genética , Nefrolitiasis/genética , Receptores Sensibles al Calcio/genética , Adolescente , Adulto , Anciano , Calcio , Estudios de Casos y Controles , China , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Adulto Joven
10.
Photochem Photobiol Sci ; 16(5): 753-758, 2017 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-28332693

RESUMEN

A new electron transfer type photoactive host-guest supramolecule was constructed by introducing (CH3)2NH2+ cations to the MOF framework. The resulting compound 1 exhibits reversible photochromic property without using photochromic components, resulting from photoinduced electron-transfer between the electron-rich anionic framework and the electron-deficient guest ions. In addition, a photoluminescence "on/off switch" occurs during the coloration-decoloration process. The raw materials are non-poisonous and harmless, hence compound 1 may be more cost-effective, clean, and harmless to the heath than existing photochromic materials.

11.
Front Bioeng Biotechnol ; 12: 1385076, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38872901

RESUMEN

During activities of daily living (ADLs), the wrist is mainly engaged in positioning and directing the hand. Researches have demonstrated that restoring wrist mobility can significantly enhance the manipulation ability, reduce body distortion caused by motion compensation, and improve the quality of life for amputees. However, most daily activities, particularly the delicate ones, place high demands on the ability of wrist to maintain a certain rotation angle, also known as non-back-drivable ability, which poses a challenge to the design of prosthetic wrists. To address this issue, various solutions have been proposed, including motor holding brakes, high reduction ratio reducers, and worm gears. However, the motor holding brake only functions after a power outage and cannot continuously prevent torque from the load end. The latter two solutions may alter the transmission ratio, resulting in reduced movement speed and transmission efficiency. Therefore, how to design a miniaturized non-back-drivable mechanism without changing the transmission ratio so that the forearm rotational freedom can be locked at any position for any duration is a problem to be solved in the research of prosthetic wrist designs. This paper presents a line-contact based non-back-drivable clutch (NBDC) that does not cause changes in the transmission ratio, ensuring the motion performance of the prosthetic limb. At the same time, it does not introduce additional friction in the forward transmission process, guaranteeing the overall efficiency. Most importantly, it only allows the torque transmitting from the motor to the load, prevents the load reversely from driving back even in a power failure condition, significantly improving the stability, safety, and comfort. Detailed kinematic and static analyses of the working process has been conducted, and transient dynamics simulation has been performed to verify its effectiveness. Through experiments, it is demonstrated that the self-locking torque of the output end could reach approximately 600 Nmm, and the unlocking torque of the input end is about 80 Nmm, which can be effectively integrated in prosthetic wrist rotation joints, contributing to the performance, safety and energy saving of prosthetic joint systems.

12.
Biomimetics (Basel) ; 9(6)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38921210

RESUMEN

In humanitarian aid scenarios, the model of cumulative capacitated vehicle routing problem can be used in vehicle scheduling, aiming at delivering materials to recipients as quickly as possible, thus minimizing their wait time. Traditional approaches focus on this metric, but practical implementations must also consider factors such as driver labor intensity and the capacity for on-site decision-making. To evaluate driver workload, the operation times of relief vehicles are typically used, and multi-objective modeling is employed to facilitate on-site decision-making. This paper introduces a multi-objective cumulative capacitated vehicle routing problem considering operation time (MO-CCVRP-OT). Our model is bi-objective, aiming to minimize both the cumulative wait time of disaster-affected areas and the extra expenditures incurred by the excess operation time of rescue vehicles. Based on the traditional grey wolf optimizer algorithm, this paper proposes a dynamic grey wolf optimizer algorithm with floating 2-opt (DGWO-F2OPT), which combines real number encoding with an equal-division random key and ROV rules for decoding; in addition, a dynamic non-dominated solution set update strategy is introduced. To solve MO-CCVRP-OT efficiently and increase the algorithm's convergence speed, a multi-objective improved floating 2-opt (F2OPT) local search strategy is proposed. The utopia optimum solution of DGWO-F2OPT has an average value of two fitness values that is 6.22% lower than that of DGWO-2OPT. DGWO-F2OPT's average fitness value in the algorithm comparison trials is 16.49% less than that of NS-2OPT. In the model comparison studies, MO-CCVRP-OT is 18.72% closer to the utopian point in Euclidean distance than CVRP-OT.

13.
Heliyon ; 10(3): e24604, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38322876

RESUMEN

This paper aimed to investigate the role of lncRNA HCG18 (HCG18) in the progression of diabetic cardiomyopathy (DCM) and potential mechanisms. Streptozocin (STZ) was used to induce DCM model in rats, which was confirmed by blood glucose concentration, body weight, and HE staining. Myocardial apoptosis was detected by TUNEL. H9c2 cardiomyocytes were used to construct cell models of DCM through treatment of high glucose. The results showed that HCG18 was overexpressed in STZ induced DCM rat model and high glucose induced H9c2 cardiomyocytes. Si-HCG18 significantly increased cell viability, reduced cell apoptosis, attenuated activities of myocardial enzymes and enhanced activities of antioxidant enzymes in STZ induced DM model and high glucose induced H9c2 cardiomyocytes, while the results of upregulation of HCG18, in high glucose induced H9c2 cardiomyocytes, were opposite with that of si-HCG18. MiR-9-5p was a target of HCG18, and which was down-regulated in cardiomyocytes of DCM. The overexpression of miR-9-5p could neutralize the high glucose induced cardiomyocyte injury, and the silence of miR-9-5p could reverse the effect of si-HCG18 on high glucose induced cardiomyocytes. MiR-9-5p could directly target to IGF2R, and IGF2R was overexpressed in cardiomyocytes of DCM. Up-regulation of IGF2R can reverse the protective effect of si-HCG18 on cardiomyocytes. Taken together, HCG18 is significantly increased in cardiomyocytes of DCM. Down-regulation of HCG18 can improve cardiomyocyte injury through miR-9-5p/IGF2R axis in DCM.

14.
J Pain ; 24(5): 782-795, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36509176

RESUMEN

Temporomandibular disorder (TMD) pain that involves inflammation and injury in the temporomandibular joint (TMJ) and/or masticatory muscle is the most common form of orofacial pain. We recently found that transient receptor potential vanilloid-4 (TRPV4) in trigeminal ganglion (TG) neurons is upregulated after TMJ inflammation, and TRPV4 coexpresses with calcitonin gene-related peptide (CGRP) in TMJ-innervating TG neurons. Here, we extended these findings to determine the specific contribution of TRPV4 in TG neurons to TMD pain, and examine whether sensory neuron-TRPV4 modulates TMD pain via CGRP. In mouse models of TMJ inflammation or masseter muscle injury, sensory neuron-Trpv4 conditional knockout (cKO) mice displayed reduced pain. Coexpression of TRPV4 and CGRP in TMJ- or masseter muscle-innervating TG neurons was increased after TMJ inflammation and masseter muscle injury, respectively. Activation of TRPV4-expressing TG neurons triggered secretion of CGRP, which was associated with increased levels of CGRP in peri-TMJ tissues, masseter muscle, spinal trigeminal nucleus, and plasma in both models. Local injection of CGRP into the TMJ or masseter muscle evoked acute pain in naïve mice, while blockade of CGRP receptor attenuated pain in mouse models of TMD. These results suggest that TRPV4 in TG neurons contributes to TMD pain by potentiating CGRP secretion. PERSPECTIVE: This study demonstrates that activation of TRPV4 in TG sensory neurons drives pain by potentiating the release of pain mediator CGRP in mouse models of TMJ inflammation and masseter muscle injury. Targeting TRPV4 and CGRP may be of clinical potential in alleviating TMD pain.


Asunto(s)
Artritis , Trastornos de la Articulación Temporomandibular , Ratones , Animales , Péptido Relacionado con Gen de Calcitonina/metabolismo , Canales Catiónicos TRPV , Trastornos de la Articulación Temporomandibular/complicaciones , Células Receptoras Sensoriales/metabolismo , Dolor Facial , Ganglio del Trigémino/metabolismo , Inflamación
15.
J Hazard Mater ; 441: 129875, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36067554

RESUMEN

Although iron-based metal-organic frameworks (Fe-MOFs) have displayed the photocatalytic activity, there is still abundant room for improving their photocatalytic performance through tuning the structures. In this work, four novel iron-based metal-organic frameworks (Fe-MOFs) were successfully synthesized via ligand modulation for better photocatalytic Cr(VI) reduction, in which MTBDC-TPT-Fe had the highest catalytic activity (MTBDC = 2,5-bis(methylthio)terephthalic acid, TPT = 2,4,6-tri(4-pyridyl)- 1,3,5-triazine). The boosted photocatalytic reduction may be mainly ascribed to the enhanced electron push-pull effect between iron-oxygen clusters and organic ligands. The introduction of -SCH3 groups can enhance the light absorption and donate electrons to iron center under visible-light irradiation, meanwhile the separation and transfer of photogenerated charge carriers can be enhanced resulting from the electron-pulling effect when introducing TPT. Moreover, enhanced specific surface areas and positive skeleton charge due to the introduction of TPT may improve active sites exposure and Cr(VI) adsorption, thereby enhancing photocatalytic Cr(VI) reduction activity without the presence of any assisted scavengers. In addition, the photocatalytic mechanism (i.e. active species) were also studied and presented. This work confirmed an effective structure-performance regulation strategy on Fe-MOFs for photocatalytic Cr(VI) reduction.

16.
Phys Rev E ; 105(2-1): 024204, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35291109

RESUMEN

We numerically investigate the rectification of the probability flux and dynamical relaxation of particles moving in a system with and without noise. The system, driven by two external forces, consists of two substrate potentials that have identical shapes and different potential barriers with different friction coefficients. The deterministic model exhibits the perfect rectification of the probability flux, ratchet effect, and the dependence of the unpredictability of the dynamics on basin of attraction. In contrast, the stochastic model displays that the rectification is sensitive to the temperature and an external bias. They can induce kinetic phase transitions between no transport and a finite net transport. These transitions lead to an unexpected phenomenon, called negative rectification. The results are analyzed through the corresponding time-dependent diffusion coefficient, information entropy (IE), etc. At a low temperature, anomalous diffusions occur in system. For the occurrence of the flux in certain parameter regimes, the larger the diffusion is, the smaller the corresponding IE is, and vice versa. We also present the selected parameter regimes for the emergence of the rectification and negative rectification. Additionally, we study the rectification of the interacting particles in the system and find that the flux may depend on the coupling strength and the number of the interacting particles, and that collective motions occur for the forward flux. Our work provides not only a way of the rectification for the transport of various particles (e.g., ions, electrons, photons, phonons, molecules, DNA chains, nanoswimmers, dust particles, etc.) in physics, chemistry, biology, and material science, but also a design of various circuits.

17.
Phys Rev E ; 106(3-1): 034208, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36266857

RESUMEN

Stochastic resetting causes kinetic phase transitions, whereas its underlying physical mechanism remains to be elucidated. We here investigate the anomalous transport of a particle moving in a chaotic system with a stochastic resetting and a rough potential and focus on how the stochastic resetting, roughness, and nonequilibrium noise affect the transports of the particle. We uncover the physical mechanism for stochastic resetting resulting in the anomalous transport in a nonlinear chaotic system: The particle is reset to a new basin of attraction which may be different from the initial basin of attraction from the view of dynamics. From the view of the energy landscape, the particle is reset to a new energy state of the energy landscape which may be different from the initial energy state. This resetting can lead to a kinetic phase transition between no transport and a finite net transport or between negative mobility and positive mobility. The roughness and noise also lead to the transition. Based on the mechanism, the transport of the particle can be tuned by these parameters. For example, the combination of the stochastic resetting, roughness, and noise can enhance the transport and tune negative mobility, the enhanced stability of the system, and the resonant-like activity. We analyze these results through variances (e.g., mean-squared velocity, etc.) and correlation functions (i.e., velocity autocorrelation function, position-velocity correlation function, etc.). Our results can be extensively applied in the biology, physics, and chemistry, even social system.

18.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 31(6): 794-8, 2011 Jun.
Artículo en Zh | MEDLINE | ID: mdl-21823426

RESUMEN

OBJECTIVE: To study the effect o f Bushen Huoxue Decoction (BHD) on neurobiochemical markers in the hippocampus of female rats with repeated immobilization stress. METHODS: Sixty female rats were randomly divided into the normal group, the model group, the positive control group (treated with Liuwei Dihuang Pill at the dose of 3.3 g crude drug/kg), and the high, middle, and low BHD treated groups (at the dose of 8, 4, 2 g crude drug/kg), ten in each group. Chronic psychological stress was induced using repeated immobilization stress in rats. Medication was conducted by gastrogavage while modeling once a day for twenty successive days. The hippocampal neurohumoral levels were detected with high-performance liquid chromatography. The expression levels of BDNF and its receptor in the hippocampus were detected by Westem blot. Effect of BHD on neurobiochemical markers in the hippocampus of rats with repeated immobilization stress was observed. RESULTS: The levels of Glu, GABA, and BDNF in the hippocampus of the normal group were 1280.0 +/- 258.3 ng/mg, 588.3 +/- 115.1 ng/mg, and 13.26 +/- 2.57 gray value, respectively. But the hippocampal neurohumoral levels and the expression of BDNF in the model group obviously decreased when compared with the normal group, being 1016.9 +/- 215.9 ng/mg, 485.1 +/- 71.0 ng/mg, and 7.23 +/- 0.61 gray value, respectively. The levels of Glu (ng/mg) in hippocampus of the three BHD treated groups were 1459.1 +/- 413.5, 1894.7 +/- 542.8, and 1373.3 +/- 345.7, respectively. GABA levels (ng/mg) inthe hippocampus were 631.6 +/- 161.4, 899.1 +/- 262.1, and 656.4 +/- 140.8, respectively. BDNF levels (gray value) were 16.57 +/- 1.52, 29.85 +/- 1.37, and 24.44 +/- 3.81, respectively, significantly higher than that of the model group (P<0.05, P<0.01). The level of Glu in the positive control group (1216.5 +/- 193.8 ng/mg) was significantly higher than that of model group (P<0.05). CONCLUSION: BHD showed significant accommodation on the hippocampal neurohumoral levels and the expression of BDNF in the female rats with repeated immobilization stress.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Hipocampo/metabolismo , Restricción Física , Estrés Psicológico/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Femenino , Ácido Glutámico/metabolismo , Hipocampo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptor trkB/metabolismo , Ácido gamma-Aminobutírico/metabolismo
19.
J Interv Card Electrophysiol ; 60(3): 529-533, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32424664

RESUMEN

BACKGROUND: New-onset atrial fibrillation (AF) is common after cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) ablation. The meta-analysis was conducted to evaluate the benefit of prophylactic pulmonary vein isolation (PVI) in typical AFL patients. METHODS: Randomized controlled trials (RCT) comparing prophylactic PVI to CTI ablation alone in typical AFL patients without prior documentation of AF were identified in the MEDLINE, EMBASE, and Cochrane databases. RESULTS: Four RCTs met the inclusion criteria. A total of 357 patients with follow-up of 20 ± 9 months were included. More patients in prophylactic PVI group were free from atrial arrhythmias (AA) compared with those in CTI group (69% versus 50%, OR = 2.36, 95% CI: 1.51 to 3.68; P = 0.0001). In the subgroup of age > 55, prophylactic PVI showed even higher incidence of freedom from AA. There is a lower occurrence of AF in prophylactic PVI group (27% versus 46%, OR = 0.45, 95% CI: 0.28 to 0.73; P = 0.001) and no difference of complications between prophylactic PVI group and CTI group (4% versus 2%; P = 0.33). CONCLUSION: Our study indicated the efficacy and safety of prophylactic PVI during CTI ablation in typical AFL patients without AF history, especially for elder patients. Large prospective RCTs are warranted to confirm the benefit of prophylactic PVI in typical AFL.


Asunto(s)
Fibrilación Atrial , Aleteo Atrial , Ablación por Catéter , Venas Pulmonares , Anciano , Fibrilación Atrial/cirugía , Aleteo Atrial/cirugía , Humanos , Venas Pulmonares/cirugía , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Resultado del Tratamiento
20.
Mol Neurobiol ; 58(6): 2836-2850, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33515176

RESUMEN

Orofacial pain, including temporomandibular joint disorders pain, trigeminal neuralgia, dental pain, and debilitating headaches, affects millions of Americans each year with significant population health impact. Despite the existence of a large body of information on the subject, the molecular underpinnings of orofacial pain remain elusive. Two decades of research has identified that transient receptor potential (TRP) ion channels play a crucial role in pathological pain. A number of TRP ion channels are clearly expressed in the trigeminal sensory system and have critical functions in the transduction and pathogenesis of orofacial pain. Although there are many similarities, the orofacial sensory system shows some distinct peripheral and central pain processing and different sensitivities from the spinal sensory system. Relative to the extensive review on TRPs in spinally-mediated pain, the summary of TRPs in trigeminally-mediated pain has not been well-documented. This review focuses on the current experimental evidence involving TRP ion channels, particularly TRPV1, TRPA1, TRPV4, and TRPM8 in orofacial pain, and discusses their possible cellular and molecular mechanisms.


Asunto(s)
Dolor Facial/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo , Animales , Dolor Facial/fisiopatología , Humanos , Neuralgia/metabolismo , Neuralgia/fisiopatología , Neuralgia del Trigémino/metabolismo , Neuralgia del Trigémino/fisiopatología
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