Mechanical pain is one of the most common causes of clinical pain, but there remains a lack of effective treatment for debilitating mechanical and chronic forms of neuropathic pain. Recently, neurotoxin GsMTx4, a selective mechanosensitive (MS) channel inhibitor, has been found to be effective, while the underlying mechanism remains elusive. Here, with multiple rodent pain models, we demonstrated that a GsMTx4-based 17-residue peptide, which we call P10581, was able to reduce mechanical hyperalgesia and neuropathic pain. The analgesic effects of P10581 can be as strong as morphine but is not toxic in animal models. The anti-hyperalgesic effect of the peptide was resistant to naloxone (an μ-opioid receptor antagonist) and showed no side effects of morphine, including tolerance, motor impairment, and conditioned place preference. Pharmacological inhibition of TRPV4 by P10581 in a heterogeneous expression system, combined with the use of Trpv4 knockout mice indicates that TRPV4 channels may act as the potential target for the analgesic effect of P10581. Our study identified a potential drug for curing mechanical pain and exposed its mechanism.

OBJECTIVE To explore the prognostic significance of the prognostic nutrition index(PNI)in patients with hypopharyngeal cancer undergoing surgical treatment.METHODS Clinical and pathological data of 117 patients with hypopharyngeal carcinoma who underwent surgical treatment at the center of Otolaryngology Head and Neck Surgery of Beijing Friendship Hospital,Capital Medical University from May 2014 to June 2022 were collected.The prognostic significance of hematological indicators such as PNI and neutrophil to lymphocyte ratio(NLR),platelet to lymphocyte ratio(PLR),and systemic immune inflammation index(SⅡ)were investigated.The time-dependent receiver operating characteristic(tROC)curves were used to analyze the sensitivity and specificity of various hematological indicators and to determine their optimal cutoffvalues.The Kaplan-Meier method was used to plot the postoperative survival curve,and the Cox regression model was used to analyze the correlation between PNI and overall survival(OS)and disease-free survival(DFS).RESULTS 117 patients were enrolled in this cohort,of which 109 were clinically classified as advanced stage(Ⅲ-Ⅳ).63 cases underwent surgery to preserve laryngeal function.The 5-year OS is 46.07％.According to the analysis of the tROC curve,the optimal cutoffvalue for PNI is 46.75.PNI is correlated with tumor T staging,NLR,PLR,and SⅡ.Kaplan Meier univariate analysis showed that PNI was significantly correlated with OS and DFS(P<0.05).In addition,tumor N-stage,postoperative complications,adverse pathological prognostic factors,NLR,PLR,and SⅡ were all significantly correlated with OS(P<0.05).Tumor N-stage,laryngeal preservation,postoperative complications,NLR,and SⅡ were significantly correlated with DFS(P<0.05).The Cox multivariate analysis results indicated that PNI,tumor N-stage,and postoperative complications were independent factors affecting OS and DFS.CONCLUSION Preoperative PNI,tumor N-stage,and postoperative complications are independent risk factors for OS and DFS in patients with hypopharyngeal carcinoma.PNI,as a prognostic indicator for predicting hypopharyngeal cancer patients,is superior to other hematological indicators.

This paper systematically reviews the phased development history of spacesuit technology across various nations,analyzes its core technologies and breakthroughs,points out the limitations of current spacesuit technology,and explores future directions for spacesuit development in response to deep-space exploration and commercialization demands.It clarifies that spacesuits are transitioning from passive protective gear to intelligent operational platforms,requiring interdisciplinary innovations to overcome key challenges such as lightweight design,adaptive systems,high reliability,and efficient human-machine interaction.

Objective With the development of manned space missions to the moon and space exploration,extravehicular activities become more frequent and extravehicular mission become more complex,which puts forward higher requirements for the extravehicular spacesuit.In order to ensure the ergonomics of spacesuit,the flexible joints are usually adopted in the limbs of spacesuit.The structural design of large angle of movement and low resistance joints is the basic for ensuring the ergonomics of spacesuit.Methods This study established a method of spacesuit joint structure to analysis the motion characteristic of typical joints.Firstly,the structure and activity characteristics of the spacesuit and lunar space suits were comprehensively analyzed,and the activity characteristics of different typical structure are qualitatively analyzed based on existing empirical method.Then,the dynamics of typical structure was analyzed by finite element model.By studying the change trend of motion of spacesuit joint with motion angle,and the motion characteristic curve was obtained.Finally,the model was studied according to different structural size parameters.The influence of structural parameters on the motion characteristics was analyzed,and the curves was obtained to provide a basis for design of spacesuit motion joint structure.Results Through the above analysis,the motion characteristics of different typical structure are obtained qualitatively.And the influence of different structure parameters on the motion characteristics was analyzed.This establishes the method basis for structure design.Conclusion The study was carried out a method based on finite element model for joint motion analysis,which is suitable for the design of typical joint structure of spacesuit.

Objective The effect of lunar dust adhesion performance by fiber surface characteristics were investigated for the lunar dust adhesion mitigation of spacesuits.Methods In this research,an adhesion test method under ultraviolet ray radiation in vacuum was developed to measure the adhesion quantity of simulated lunar dust on fiber materials.Based on the microscopic image of the fiber sample after test,the influence of conductive and surface energy characteristics of the fiber materials on the lunar dust adhesion performance was studied.Results The simulated lunar dust were activated under ultraviolet ray radiation,which induced an increase of the adhesion quantity of simulated lunar dust on fiber materials;Lower surface energy or higher conductive characteristics of the fiber was both beneficial to reduce the adhesion quantity of simulated lunar dust.Conclusion The static electric forces were likely to be the major forces between the fiber and the lunar dust under ultraviolet ray radiation in vacuum.In addition to reducing surface energy,improving conductive characteristics of the fiber was more beneficial to reduce the adhesion quantity of simulated lunar dust.

Ripple structure is widely used in space suits,and the predicted trajectory motion is realized according to its large deformation behavior.Due to the complexity of irregular bellows structure,the existing researches are mostly based on the display dynamic method,and lack the systematic analysis of geometric nonlinearity and the effect of shell section thickness under the framework of statics.This study combines statics and arc length method(Riks),introduces linear buckling mode defects,and analyzes the ultimate bending behavior of irregular bellows with different shell thicknesses.It is concluded that the thick-shell model exhibits higher apparent deformation tolerance due to geometric softening effect,and the contact force distribution between ripples can be accurately extracted by static analysis,which provides a basis for the inversion of external force loads.The deformation mode of bellows after introducing defects based on statics-Riks is proposed,and the control mechanism of shell section thickness on deformation path is revealed.

When conducting extravehicular activities under low-gravity conditions like on the moon,the weight of the spacesuit is one of the loads that human body has to bear.The centroid position of the spacesuit will affect the motion control of the human-spacesuit system.In order to reveal the influence of the centroid position of the lunar spacesuit on human motion under lunar-gravity,a suspended 1/6 gravity simulation system was used for the experiment.When subjects were under different load centroids which include front and back on sagittal plane,left and right on coronal plane,up and down on cross-section plane,near to coordinate origin,the postures and plantar pressures of subjects during three typical movements:standing,single-knee standing and walking were captured.Inverse dynamics solution is adopted to analyze the joint torques of human body in above conditions.Combined with the subjective evaluation,the appropriate load centroid area was analyzed by comparative.The experiment shows that,human is non-sensitive to the up and down change of load centroid,the after is back change,the front and right load centroid are the mostly avoided.The results obtained by this study will provide a reference for the layout design of the lunar spacesuit.

Objective Maintain a sable differential pressure inside the Underwater Positive Pressure Protective Suit(UPPPS)to ensure normal breathing and safe underwater operations for the diver.Methods Utilize a pressure regulator as the UPPPS's pressure control valve to automatically maintain the differential pressure inside the suit.Results By establishing a physical model,the relationship between the steady-state differential pressure with the ventilation flow rate and the ambient pressure was obtained.(1)The ventilation flow rate is positively correlated with the steady-state differential pressure,the higher the ventilation flow rate,the greater the steady-state differential pressure.(2)At the same ventilation flow rate,the larger the ambient pressure is,the smaller the steady-state differential pressure is.Underwater unmanned and manned experiments using the UWT suit were conducted.The expermental results are in agreement with the theoretical analysis.Conclusion The performance of pressure regulator has been verified by the underwater experiments,it effectively stabilizes the differential pressure within the UPPPS.

Aiming at the problem that the amount of Oxygen remaining and available time can not be accurately predicted while an astronaut conducting extravehicular activities(EVAs)in EVA spacesuit.Research the oxygen consumption process of EVA spacesuit.The model and algorithm of oxygen consumption are established by the gas state equation including compressibility and temperature coefficient,combined with human metabolism and micro leakage characteristics of spacesuit.Experimental data show that the orecast model and algorithm hasing high accuracy and practicability.