Objective To identify the physiological variables associated with the development of acute mountain sickness(AMS).Methods Eighty four young Chinese men residing at low altitude were taken to an altitude of 4000 m with...Objective To identify the physiological variables associated with the development of acute mountain sickness(AMS).Methods Eighty four young Chinese men residing at low altitude were taken to an altitude of 4000 m within 40 hours.At sea level and at high altitude,we measured the heart rate,blood pressure,and peripheral oxygen saturation(SpO2)respectively.We also collect blood samples from each participants before and after the altitude elevation.The blood routine and biochemical examinations were performed for all blood samples.The revised Lake Louise Criteria was adopted to diagnose AMS after the subjects arrived at the target high altitude.The association between the presence of AMS and subjects’physiological variables were analysed statistically.Results Of 84 participants,34(40.5%)developed AMS.Compared with non AMS group,in the AMS group,the percentage of neutrophils was significantly higher(64.5%±11.2%vs.58.1%±8.8%,P=0.014),while the level of SpO2 was significantly lower(79.4%±5.4%vs.82.7%±5.6,P=0.008).Binary logistic regression analyses emphasized the association of neutrophils(OR:1.06,95%CI:1.01-1.12,P=0.034)and SpO2 level(OR:0.87,95%CI:0.79-0.95,P=0.004)with the development of AMS.Conclusion The ability to sustain SpO2 after altitude elevation and the increase of neutrophils were associated with the development of AMS in young males.展开更多
OBJECTIVE:To evaluate the protective effect of Shouzhangshen(Rhizoma Gymnadeniae Crassinervidis)extract against acute high altitude hypoxia-induced brain injury in mice.METHODS:Sixty C57BL/6J mice were selected and as...OBJECTIVE:To evaluate the protective effect of Shouzhangshen(Rhizoma Gymnadeniae Crassinervidis)extract against acute high altitude hypoxia-induced brain injury in mice.METHODS:Sixty C57BL/6J mice were selected and assigned to six groups(n=10):normal control group,low-pressure hypoxia group,positive control group(dexamethasone 500 mg/kg),and three groups treated with Shouzhangshen extract(250,500,and 750 mg/kg,respectively).The Morris water maze test was performed to evaluate alterations in spatial learning and memory deficits.Nissl staining was performed to detect Nissl bodies and neuron damage.Hypoxia-inducible factor(HIF)-1α,interleukin(IL)-1β,tumor necrosis factor(TNF)-α,vascular endothelial growth factor(VEGF),and malondialdehyde(MDA)expression in brain tissue and serum,as well as superoxide dismutase(SOD)and glutathione(GSH)activity in brain tissues were measured by enzyme-linked immunosorbent assays,quantitative real-time-polymerase chain reaction and western blots.RESULTS:The Morris water maze test results showed that Shouzhangshen extract can significantly reduce the latency and swimming distance to escape onto a visible platform,increase neuron density and hierarchy and the number of pyramidal neurons,and decrease the expression of HIF-1α,IL-1β,TNF-α,and VEGF mRNAs and proteins in both brain tissue and serum(P<0.05).Furthermore,significantly lower MDA expression and higher GSH activity were detected in the three groups treated with Shouzhangshen compared with the low-pressure hypoxia group(P<0.05).However,no significant alteration was observed for SOD activity(P>0.05).CONCLUSION:Our findings suggest that Shouzhangshen extract may have a significant effect on acute high altitude hypoxia-induced brain injury in mice.展开更多
Low pressure,low oxygen concentration,and intense ultraviolet（UV）radiation in high-altitude environments,can cause oxidative stress which can trigger mountain sickness.A recent study demonstrated that hydrogen gas w...Low pressure,low oxygen concentration,and intense ultraviolet（UV）radiation in high-altitude environments,can cause oxidative stress which can trigger mountain sickness.A recent study demonstrated that hydrogen gas with a good permeability in biological membranes can treat various disorders by exerting its selective anti-oxidation and anti-inflammatory effects,indicating that hydrogen therapy plays a role in scavenging free radicals and in balancing oxidation and anti-oxidation systems of ceils. Therefore, we hypothesize that inhaling low-dose hydrogen or drinking hydrogen-saturated water is a novel and simple method to prevent and treat oxidative stress injury caused by low pressure, low oxygen concentration and intense UV radiation in plateaus, thus reducing the risk of mountain sickness.展开更多
Some of my Tibetan friends joke that the reason I don’t get altitude sickness,even at elevations around 5,000 meters,is because,in my previous life,I was Tibetan.
At high altitudes,which typically exceed 2500 m,approximately 80 million people reside permanently,with over a million visitors annually.The primary effect of high altitude is hypobaric hypoxia,which leads to decrease...At high altitudes,which typically exceed 2500 m,approximately 80 million people reside permanently,with over a million visitors annually.The primary effect of high altitude is hypobaric hypoxia,which leads to decreased oxygen availability and a cascade of physiological responses.However,inadequate or excessive responses can lead to malacclimatization,resulting in hypoxemia and various high-altitude illnesses,including acute mountain sickness(AMS),high-altitude cerebral edema(HACE),high-altitude pulmonary edema(HAPE),chronic mountain sickness(CMS),and high-altitude pulmonary hypertension(HAPH).Acute altitude illnesses(AMS,HACE,and HAPE)stem from inadequate acclimatization,whereas chronic conditions(CMS and HAPH)reflect prolonged or excessive adaptive responses.This review briefly summarizes the current knowledge on the clinical manifestations,epidemiology,and risk factors for high-altitude diseases.Additionally,this review systematically discusses the most recent pathophysiological mechanisms underlying these conditions,with a special emphasis on genetic susceptibility and chronic altitude illness(CMS and HAPH).Furthermore,a comprehensive overview of current prevention and treatment strategies is provided,emphasizing the promising effects of natural medicines,especially traditional Tibetan medicines.Despite extensive research,the exact mechanisms underlying these illnesses remain elusive,and options for their management are still limited.This review aims to provide novel insights into the pathogenic mechanisms of these complex conditions and guide future research directions to improve the prevention and management of high-altitude illnesses.展开更多
Background:A combination of molecular docking,molecular dynamics simulations,and herbal network pharmacology was used to investigate the shared key targets and potential mechanisms underlying the preventive effects of...Background:A combination of molecular docking,molecular dynamics simulations,and herbal network pharmacology was used to investigate the shared key targets and potential mechanisms underlying the preventive effects of Ginkgo biloba active compounds against acute mountain sickness(AMS)and ischemic stroke(IS).Material and Methods:The Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform was used to screen the main active compounds of Ginkgo biloba and their corresponding targets.We obtained AMS-related genes by mining several databases and cross-correlated them with key active compounds of Ginkgo biloba to identify relevant action targets for treating AMS.The STRING database was used to construct a protein–protein interaction network of the effect of Ginkgo biloba active compounds on AMS targets.The expression of genes in the network was analyzed in an IS dataset to identify common key targets of Ginkgo biloba active compounds for both AMS and IS prevention.Results:The intersection between the targets of Ginkgo biloba active compounds and AMS-related genes identified 43 overlapping genes.Analysis of the protein–protein interaction network showed that VEGFA,TP53,SERPINE1,and PTGS2 were among the key hub genes.Analysis of the IS dataset identified significant differences in the expression levels of CAT,TP53,CXCL8,NFKBIA,and PTGS2.These genes were used to construct a visual nomogram prediction model for IS prognosis with promising clinical implications.Molecular docking and molecular dynamics simulations indicated that sesamin stably targeted and bound to PTGS2.Conclusions:Active ingredients of Ginkgo biloba,including luteolin,quercetin,and sesamin,have the potential to modulate the development of AMS and IS through targeted interactions with key proteins,including TP53,CXCL8,NFKBIA,PTGS2,and CAT.展开更多
The method presented in the article is based on a complex simulation model of gas-dynamic processes that take place in sectioned cabins during depressurization.This model allows the theoretical calculation of decompre...The method presented in the article is based on a complex simulation model of gas-dynamic processes that take place in sectioned cabins during depressurization.This model allows the theoretical calculation of decompression parameters(decompression time,cabin pressure,gas leakage from the cabin)depending on flight parameters and design features of the aircraft pressurised cabin(height,cabin volume,defect area,etc.)and determine the interdependence of pressure control parameters in critical operating modes.In computational experiments simulating decompression during depressurisation,the rate of cabin pressure drop as a function of the defect area,residual overpressure,decompression time,values of drops between compartment sections and mass flow rate during pressure changes;safe descent height and other parameters were determined.On the basis of computational experiments,a methodology for assessing the portability of decompression was developed,taking into account different levels of impact tolerance,allowing for a rational choice of hermetic and gas dynamic parameters of the cabin,as well as flight performance characteristics,taking into account the possible decompression of the cabin in flight or,conversely,with the specified parameters of the cabin and flight data at the design stage of the aircraft to assess the degree of danger in case of depressurization and to provide in advance a set of security measures.The transition for decompression safety analysis along the Chadov V.I.curve has advantages since it is applicable for various types of aircraft from spacecraft to aircraft and for various atmospheres with different combinations of pressures and concentrations.展开更多
基金Fund supported by the National Science and Technology Major Projects for Major New Drugs Innovation and Development(No.2014ZX09J14102-02A)~~
文摘Objective To identify the physiological variables associated with the development of acute mountain sickness(AMS).Methods Eighty four young Chinese men residing at low altitude were taken to an altitude of 4000 m within 40 hours.At sea level and at high altitude,we measured the heart rate,blood pressure,and peripheral oxygen saturation(SpO2)respectively.We also collect blood samples from each participants before and after the altitude elevation.The blood routine and biochemical examinations were performed for all blood samples.The revised Lake Louise Criteria was adopted to diagnose AMS after the subjects arrived at the target high altitude.The association between the presence of AMS and subjects’physiological variables were analysed statistically.Results Of 84 participants,34(40.5%)developed AMS.Compared with non AMS group,in the AMS group,the percentage of neutrophils was significantly higher(64.5%±11.2%vs.58.1%±8.8%,P=0.014),while the level of SpO2 was significantly lower(79.4%±5.4%vs.82.7%±5.6,P=0.008).Binary logistic regression analyses emphasized the association of neutrophils(OR:1.06,95%CI:1.01-1.12,P=0.034)and SpO2 level(OR:0.87,95%CI:0.79-0.95,P=0.004)with the development of AMS.Conclusion The ability to sustain SpO2 after altitude elevation and the increase of neutrophils were associated with the development of AMS in young males.
基金Supported by the Project of the Regional Collaborative Innovation Center of Tibetan Medicine(2018XTCX013)the Central Support for the Reform and Development of Local Colleges and Universities:Rescue Protection and Construction of Tissue Culture Platform for Endangered and Precious Tibetan Medicinal Materials+3 种基金the Fund for Less Developed Regions of the National Natural Science Foundation of China(No.81960727)the Science and Technology Plan Project of Tibet(XZ201901-GA-01)the Science Research Cultivation Project of the Medical College of Tibet University(2019XSZX02)the Fund for Research Cultivation Program of Tibet University-Growth Project(ZDCZJH19-15)。
文摘OBJECTIVE:To evaluate the protective effect of Shouzhangshen(Rhizoma Gymnadeniae Crassinervidis)extract against acute high altitude hypoxia-induced brain injury in mice.METHODS:Sixty C57BL/6J mice were selected and assigned to six groups(n=10):normal control group,low-pressure hypoxia group,positive control group(dexamethasone 500 mg/kg),and three groups treated with Shouzhangshen extract(250,500,and 750 mg/kg,respectively).The Morris water maze test was performed to evaluate alterations in spatial learning and memory deficits.Nissl staining was performed to detect Nissl bodies and neuron damage.Hypoxia-inducible factor(HIF)-1α,interleukin(IL)-1β,tumor necrosis factor(TNF)-α,vascular endothelial growth factor(VEGF),and malondialdehyde(MDA)expression in brain tissue and serum,as well as superoxide dismutase(SOD)and glutathione(GSH)activity in brain tissues were measured by enzyme-linked immunosorbent assays,quantitative real-time-polymerase chain reaction and western blots.RESULTS:The Morris water maze test results showed that Shouzhangshen extract can significantly reduce the latency and swimming distance to escape onto a visible platform,increase neuron density and hierarchy and the number of pyramidal neurons,and decrease the expression of HIF-1α,IL-1β,TNF-α,and VEGF mRNAs and proteins in both brain tissue and serum(P<0.05).Furthermore,significantly lower MDA expression and higher GSH activity were detected in the three groups treated with Shouzhangshen compared with the low-pressure hypoxia group(P<0.05).However,no significant alteration was observed for SOD activity(P>0.05).CONCLUSION:Our findings suggest that Shouzhangshen extract may have a significant effect on acute high altitude hypoxia-induced brain injury in mice.
基金supported by the National Natural Science Foundation of China(Grant No.81301134,81371444)
文摘Low pressure,low oxygen concentration,and intense ultraviolet（UV）radiation in high-altitude environments,can cause oxidative stress which can trigger mountain sickness.A recent study demonstrated that hydrogen gas with a good permeability in biological membranes can treat various disorders by exerting its selective anti-oxidation and anti-inflammatory effects,indicating that hydrogen therapy plays a role in scavenging free radicals and in balancing oxidation and anti-oxidation systems of ceils. Therefore, we hypothesize that inhaling low-dose hydrogen or drinking hydrogen-saturated water is a novel and simple method to prevent and treat oxidative stress injury caused by low pressure, low oxygen concentration and intense UV radiation in plateaus, thus reducing the risk of mountain sickness.
文摘Some of my Tibetan friends joke that the reason I don’t get altitude sickness,even at elevations around 5,000 meters,is because,in my previous life,I was Tibetan.
基金supported by the Qinghai Provincial Department of Science and Technology(Grant No.2025-ZJ-748)to R.G.the Noncommunicable Chronic Diseases-National Science and Technology Major Project(Grant No.2024ZD0526900)to C.C.
文摘At high altitudes,which typically exceed 2500 m,approximately 80 million people reside permanently,with over a million visitors annually.The primary effect of high altitude is hypobaric hypoxia,which leads to decreased oxygen availability and a cascade of physiological responses.However,inadequate or excessive responses can lead to malacclimatization,resulting in hypoxemia and various high-altitude illnesses,including acute mountain sickness(AMS),high-altitude cerebral edema(HACE),high-altitude pulmonary edema(HAPE),chronic mountain sickness(CMS),and high-altitude pulmonary hypertension(HAPH).Acute altitude illnesses(AMS,HACE,and HAPE)stem from inadequate acclimatization,whereas chronic conditions(CMS and HAPH)reflect prolonged or excessive adaptive responses.This review briefly summarizes the current knowledge on the clinical manifestations,epidemiology,and risk factors for high-altitude diseases.Additionally,this review systematically discusses the most recent pathophysiological mechanisms underlying these conditions,with a special emphasis on genetic susceptibility and chronic altitude illness(CMS and HAPH).Furthermore,a comprehensive overview of current prevention and treatment strategies is provided,emphasizing the promising effects of natural medicines,especially traditional Tibetan medicines.Despite extensive research,the exact mechanisms underlying these illnesses remain elusive,and options for their management are still limited.This review aims to provide novel insights into the pathogenic mechanisms of these complex conditions and guide future research directions to improve the prevention and management of high-altitude illnesses.
基金Chinese PLA General Hospital Innovative Talent Construction Project,Grant/Award Number:20230409。
文摘Background:A combination of molecular docking,molecular dynamics simulations,and herbal network pharmacology was used to investigate the shared key targets and potential mechanisms underlying the preventive effects of Ginkgo biloba active compounds against acute mountain sickness(AMS)and ischemic stroke(IS).Material and Methods:The Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform was used to screen the main active compounds of Ginkgo biloba and their corresponding targets.We obtained AMS-related genes by mining several databases and cross-correlated them with key active compounds of Ginkgo biloba to identify relevant action targets for treating AMS.The STRING database was used to construct a protein–protein interaction network of the effect of Ginkgo biloba active compounds on AMS targets.The expression of genes in the network was analyzed in an IS dataset to identify common key targets of Ginkgo biloba active compounds for both AMS and IS prevention.Results:The intersection between the targets of Ginkgo biloba active compounds and AMS-related genes identified 43 overlapping genes.Analysis of the protein–protein interaction network showed that VEGFA,TP53,SERPINE1,and PTGS2 were among the key hub genes.Analysis of the IS dataset identified significant differences in the expression levels of CAT,TP53,CXCL8,NFKBIA,and PTGS2.These genes were used to construct a visual nomogram prediction model for IS prognosis with promising clinical implications.Molecular docking and molecular dynamics simulations indicated that sesamin stably targeted and bound to PTGS2.Conclusions:Active ingredients of Ginkgo biloba,including luteolin,quercetin,and sesamin,have the potential to modulate the development of AMS and IS through targeted interactions with key proteins,including TP53,CXCL8,NFKBIA,PTGS2,and CAT.
文摘The method presented in the article is based on a complex simulation model of gas-dynamic processes that take place in sectioned cabins during depressurization.This model allows the theoretical calculation of decompression parameters(decompression time,cabin pressure,gas leakage from the cabin)depending on flight parameters and design features of the aircraft pressurised cabin(height,cabin volume,defect area,etc.)and determine the interdependence of pressure control parameters in critical operating modes.In computational experiments simulating decompression during depressurisation,the rate of cabin pressure drop as a function of the defect area,residual overpressure,decompression time,values of drops between compartment sections and mass flow rate during pressure changes;safe descent height and other parameters were determined.On the basis of computational experiments,a methodology for assessing the portability of decompression was developed,taking into account different levels of impact tolerance,allowing for a rational choice of hermetic and gas dynamic parameters of the cabin,as well as flight performance characteristics,taking into account the possible decompression of the cabin in flight or,conversely,with the specified parameters of the cabin and flight data at the design stage of the aircraft to assess the degree of danger in case of depressurization and to provide in advance a set of security measures.The transition for decompression safety analysis along the Chadov V.I.curve has advantages since it is applicable for various types of aircraft from spacecraft to aircraft and for various atmospheres with different combinations of pressures and concentrations.
