High altitude medicine & biology最新文献

筛选
英文 中文
Is it Possible for Individuals with Pre-Existing Mental Disorders to Perform Mountain Sports at High Altitude-First Evidence from a Pilot Cross-Sectional Questionnaire Study. 已有精神障碍的人是否有可能在高海拔地区进行登山运动--一项试点横断面问卷调查研究的初步证据。
IF 1.6 4区 医学
High altitude medicine & biology Pub Date : 2024-10-09 DOI: 10.1089/ham.2024.0056
Claudia Gstir, Timo Schurr, Roxana Ehlers, Johannes Burtscher, Barbara Sperner-Unterweger, Katharina Hüfner
{"title":"Is it Possible for Individuals with Pre-Existing Mental Disorders to Perform Mountain Sports at High Altitude-First Evidence from a Pilot Cross-Sectional Questionnaire Study.","authors":"Claudia Gstir, Timo Schurr, Roxana Ehlers, Johannes Burtscher, Barbara Sperner-Unterweger, Katharina Hüfner","doi":"10.1089/ham.2024.0056","DOIUrl":"https://doi.org/10.1089/ham.2024.0056","url":null,"abstract":"<p><p>Gstir, Claudia, Timo Schurr, Roxana Ehlers, Johannes Burtscher, Barbara Sperner-Unterweger, and Katharina Hüfner. Is it possible for individuals with pre-existing mental disorders to perform mountain sports at high altitude-First evidence from a pilot cross-sectional questionnaire study. <i>High Alt Med Biol.</i> 00:00-00, 2024. <b><i>Introduction:</i></b> Mountain sports at high altitude (HA) are gaining increasing popularity, but little is known about the effect of such activities on mental health, despite a great prevalence of mental disorders. <b><i>Methods:</i></b> Data were collected using an online self-report questionnaire assessing mental and somatic disorders in individuals performing mountain sports at HA (>2,500 m above sea level [ASL]) as well as their symptom change. Nonparametric tests were used for analyses. <b><i>Results:</i></b> 251 individuals without pre-existing disorders (noD), 34 with somatic disorders (somaD), and 38 with mental disorders (mentalD; mainly depressive, eating, and anxiety disorders) participated in this study. Overall, 44.7% of the mentalD group compared with 14.7% of somaD experienced ameliorated symptoms during mountain sports at HA, while 2.6% and 8.8%, respectively, reported a worsening (χ<sup>2</sup>[2] =8.13, <i>p</i> = 0.017). People in the mentalD compared with somaD group significantly less frequently inform tour partners (41.9% vs. 90.9%; χ<sup>2</sup>[2]=16.69, <i>p</i> < 0.001) about their condition or consult their physician (2.6% vs. 26.5%; χ<sup>2</sup>[1]=8.53, <i>p</i> = 0.003) regarding their plans to perform mountain sports at HA. 14.5% of all participants reported mental symptoms at 2,500-3,500 m ASL, 23.5% between >3,500-5,500 m ASL and 31.8% >5,500 m ASL. <b><i>Conclusion:</i></b> Individuals with mental disorders often report improved mental health during mountain sports at HA, possibly due to a combination of physical activity, the alpine natural environment, and/or moderate hypoxia. The fact that tour partners and physicians are rarely informed shows the need to reduce the stigma of mental disorders in the mountain sports community. The study was prospectively registered with the German Clinical Trials Registry (DRKS00024949).</p>","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Pushing Scuba to New Heights: Approach, Decompression, and Logistical Considerations for High-Altitude Diving. 将水肺潜水推向新高度:高海拔潜水的方法、减压和后勤考虑因素。
IF 1.6 4区 医学
High altitude medicine & biology Pub Date : 2024-10-08 DOI: 10.1089/ham.2024.0108
Taylor L Yoder, Kreager A Taber, Laurens E Howle, Richard E Moon
{"title":"Pushing Scuba to New Heights: Approach, Decompression, and Logistical Considerations for High-Altitude Diving.","authors":"Taylor L Yoder, Kreager A Taber, Laurens E Howle, Richard E Moon","doi":"10.1089/ham.2024.0108","DOIUrl":"https://doi.org/10.1089/ham.2024.0108","url":null,"abstract":"<p><p>There is interest among technical, expedition, commercial, and military divers in expanding diving operations to high altitude. However, altitude diving presents unique challenges including acclimatization, increased decompression sickness (DCS) risk, and logistical and equipment considerations. Divers must plan altitude acclimatization strategies conservatively to reduce risk of acute mountain sickness and dehydration before diving. Several methods of augmenting sea level diving tables to be used at altitude have been theorized and tested both in simulated dives and high-altitude expeditions. With proper acclimatization, augmentation of standard diving tables, equipment, and safety planning, diving at high altitude may be performed in many contexts safely while minimizing risk of DCS or injury.</p>","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Acute Hypobaric Hypoxia Causes Alterations in Acetylcholine-Mediated Signaling Through Varying Expression of Muscarinic Receptors in the Prefrontal Cortex and Cerebellum of Rats' Brain. 急性低压缺氧通过改变大鼠大脑前额叶皮层和小脑中肌肉卡因受体的表达导致乙酰胆碱介导的信号转导发生改变
IF 1.6 4区 医学
High altitude medicine & biology Pub Date : 2024-10-08 DOI: 10.1089/ham.2023.0146
Narendra Kumar Sharma, Mansi Srivastava, Tikam Chand Dakal, Vipin Ranga, Pawan Kumar Maurya
{"title":"Acute Hypobaric Hypoxia Causes Alterations in Acetylcholine-Mediated Signaling Through Varying Expression of Muscarinic Receptors in the Prefrontal Cortex and Cerebellum of Rats' Brain.","authors":"Narendra Kumar Sharma, Mansi Srivastava, Tikam Chand Dakal, Vipin Ranga, Pawan Kumar Maurya","doi":"10.1089/ham.2023.0146","DOIUrl":"https://doi.org/10.1089/ham.2023.0146","url":null,"abstract":"<p><p>Sharma, Narendra Kumar, Mansi Srivastava, Tikam Chand Dakal, Vipin Ranga, and Pawan Kumar Maurya. Acute hypobaric hypoxia (HH) causes alterations in acetylcholine-mediated signaling through varying expression of muscarinic receptors in the PFC and cerebellum of rats' brain. <i>High Alt Med Biol.</i> 00:00-00, 2024. <b><i>Background:</i></b> Muscarinic receptor (CHRM) proteins are G-protein-associated acetylcholine receptors found in neuronal membranes. Five major subtypes, CHRM1-CHRM5, modulate acetylcholine in central nervous system signaling cascades. CHRM1, CHRM3, and CHRM5 are linked to Gαq/Gα11 proteins, whereas CHRM2 and CHRM4 are linked to Gαi/Gαo proteins. <b><i>Objective:</i></b> Limited research has been conducted to explore the impact of HH on CHRM gene expressions. It is caused by low oxygen availability at high altitudes, which impairs neurotransmission, cognitive performance, and physiological functions. Previous studies have shown that exposure to hypoxia leads to a reduction in CHRM receptors, which in turn causes alteration in signal transduction, physiological responses, cognitive deficits, and mood alterations. <b><i>Method:</i></b> In the present study, we have used semiquantitative PCR to measure muscarinic receptor gene expression after 6, 12, and 24 hours of HH exposure at 25,000 feet using a decompression chamber in rat brain's PFC and cerebellum. <b><i>Result:</i></b> We have found that CHRM1-CHRM5 downregulated after acute exposure to hypoxia until 12 hours, and then, the expression level of these receptors increased to 24 hours when compared with 12 hours in PFC. All subtypes have shown a similar pattern in PFC regions under hypoxia exposure. On the other hand, these receptors have shown altered expression at different time points in the cerebellum. CHRM1 and CHRM4 acutely downregulated, CHRM2 and CHRM5 downregulated, while CHRM3 upregulated after hypoxia exposure. <b><i>Conclusion:</i></b> Our study, for the first time, has shown the altered expressions of muscarinic receptors under temporal hypoxia exposure. The altered expression pattern has shown an association with acclimatization and protection against necrosis due to hypoxia. This study may pave further investigations for understanding and addressing the cognitive, behavioral, and physiological impacts of hypoxia and therapeutic development.</p>","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Noncompressible Chest Wall in Critically Buried Avalanche Victims with Cardiac Arrest: A Case Series. 重症雪崩掩埋者心脏骤停时胸壁不可压缩:病例系列。
IF 1.6 4区 医学
High altitude medicine & biology Pub Date : 2024-09-30 DOI: 10.1089/ham.2024.0104
David Eidenbenz, Alexandre Kottmann, Ken Zafren, Pierre-Nicolas Carron, Roland Albrecht, Mathieu Pasquier
{"title":"Noncompressible Chest Wall in Critically Buried Avalanche Victims with Cardiac Arrest: A Case Series.","authors":"David Eidenbenz, Alexandre Kottmann, Ken Zafren, Pierre-Nicolas Carron, Roland Albrecht, Mathieu Pasquier","doi":"10.1089/ham.2024.0104","DOIUrl":"https://doi.org/10.1089/ham.2024.0104","url":null,"abstract":"<p><p>David Eidenbenz, Alexandre Kottmann, Ken Zafren, Pierre-Nicolas Carron, Roland Albrecht, and Mathieu Pasquier. Noncompressible chest wall in critically buried avalanche victims with cardiac arrest: a case series. <i>High Alt Med Biol.</i> 00:00-00, 2024. <b><i>Introduction:</i></b> In avalanche victims with cardiac arrest, a noncompressible chest wall or frozen body is a contraindication to initiating cardiopulmonary resuscitation. The evidence sustaining this recommendation is low. <b><i>Objective:</i></b> To describe the characteristics and prehospital management of critically buried avalanche victims declared dead on site, with and without noncompressible chest walls. <b><i>Methods:</i></b> Retrospective study including all critically buried avalanche victims declared dead on site by physicians of a helicopter emergency medical service in Switzerland, from 2010 to 2019. The primary outcome was the proportion of victims with a noncompressible chest wall reported in medical records. Secondary outcomes included victims' characteristics and the relevance of the criterion, noncompressible chest wall, for management. <b><i>Results:</i></b> Among the 53 included victims, 12 (23%) had noncompressible chest walls. Victims with noncompressible chest walls had significantly longer burial durations (median 1,125 vs. 45 minutes; <i>p</i> < 0.001) and lower core temperatures (median 14 vs. 32°C; <i>p</i> = 0.01). The criterion, noncompressible chest wall, assessed in six victims, was decisive for declaring death on site in four victims. <b><i>Conclusion:</i></b> The presence of a noncompressible chest wall does not appear to be a sufficient criterion to allow to declare the death of critically buried avalanche victims. Further clinical information should be sought.</p>","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142345583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The Profiles of Venous Thromboembolism at Different High Altitudes. 不同高海拔地区的静脉血栓栓塞概况
IF 1.6 4区 医学
High altitude medicine & biology Pub Date : 2024-09-01 Epub Date: 2024-04-29 DOI: 10.1089/ham.2023.0081
Shiqiang Xiong, Jun Hou, Haixia Yang, Meiting Gong, Xin Ma, Xuhu Yang, Hongyang Zhang, Yao Ma, Liang Gao, Haifeng Pei
{"title":"The Profiles of Venous Thromboembolism at Different High Altitudes.","authors":"Shiqiang Xiong, Jun Hou, Haixia Yang, Meiting Gong, Xin Ma, Xuhu Yang, Hongyang Zhang, Yao Ma, Liang Gao, Haifeng Pei","doi":"10.1089/ham.2023.0081","DOIUrl":"10.1089/ham.2023.0081","url":null,"abstract":"<p><p>Xiong, Shiqiang, Jun Hou, Haixia Yang, Meiting Gong, Xin Ma, Xuhu Yang, Hongyang Zhang, Yao Ma, Liang Gao, and Haifeng Pei. The profiles of venous thromboembolism at different high altitudes <i>High Alt Med Biol.</i> 25:223-225, 2024.-This study investigated the incidence of venous thromboembolism (VTE) in high altitude (HA) and very HA areas. Patients with deep vein thrombosis (DVT) or pulmonary embolism (PE) diagnosed between 2004 and 2022 in Yecheng, China, were retrospectively analyzed. The results showed that patients with PE at very HA had a higher risk of lower extremity DVT (OR 16.3 [95% CI 1.2-223.2], <i>p</i> = 0.036), than those at HA, especially in the early stages of very HA entry, and the harsh environment of very HA further exacerbated the risk of VTE. These findings emphasize the higher risk of PE development in very HA and the need for enhanced prevention and treatment in this area.</p>","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":" ","pages":"223-225"},"PeriodicalIF":1.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140858738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Evaluation and Management of the Individual with Recurrent High Altitude Pulmonary Edema. 复发性高海拔肺水肿患者的评估和管理。
IF 1.6 4区 医学
High altitude medicine & biology Pub Date : 2024-09-01 Epub Date: 2024-04-29 DOI: 10.1089/ham.2024.0024
Andrew M Luks, Colin K Grissom
{"title":"Evaluation and Management of the Individual with Recurrent High Altitude Pulmonary Edema.","authors":"Andrew M Luks, Colin K Grissom","doi":"10.1089/ham.2024.0024","DOIUrl":"10.1089/ham.2024.0024","url":null,"abstract":"<p><p>Luks AM, Grissom CK. Evaluation and Management of the Individual with Recurrent HAPE. <i>High Alt Med Biol.</i> 25:238-246, 2024. Individuals with a history of acute altitude illness often seek recommendations from medical providers on how to prevent such problems on future ascents to high elevation. Although many of these cases can be managed with pharmacologic prophylaxis and counseling about the appropriate rate of ascent alone, there are some situations in which further diagnostic evaluation may also be warranted. One such situation is the individual with recurrent episodes of high altitude pulmonary edema (HAPE), as one of several predisposing factors may be present that warrants additional interventions beyond pharmacologic prophylaxis and slow ascent and may even preclude future travel to high altitude. This review considers this situation in greater detail. Structured around the case of an otherwise healthy 27-year-old individual with recurrent episodes of HAPE who would like to climb Denali (6,190 m), the review examines the known risk factors for disease and then provides guidance regarding when and how to evaluate such individuals and appropriate steps to prevent HAPE on further ascents to high elevation. Except in rare circumstances, a history of recurrent HAPE does not preclude further ascent to high elevation, as a multipronged approach including pharmacologic prophylaxis, careful planning about the rate of ascent, and the degree of physical effort and other strategies, such as preacclimatization, staged ascent, and use of hypoxic tents, can be employed to reduce the risk of recurrence with future travel.</p>","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":" ","pages":"238-246"},"PeriodicalIF":1.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140863778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Changes in Fingertip Cold-Induced Vasodilatation (Hunting Reaction) on Acute Exposure to Altitude. 指尖冷诱导的血管舒张(狩猎反应)在急性暴露于海拔高度时的变化。
IF 1.6 4区 医学
High altitude medicine & biology Pub Date : 2024-09-01 Epub Date: 2024-05-13 DOI: 10.1089/ham.2023.0106
Alexandre Fossati, Aleid C J Ruijs
{"title":"Changes in Fingertip Cold-Induced Vasodilatation (Hunting Reaction) on Acute Exposure to Altitude.","authors":"Alexandre Fossati, Aleid C J Ruijs","doi":"10.1089/ham.2023.0106","DOIUrl":"10.1089/ham.2023.0106","url":null,"abstract":"<p><p>Fossati, Alexandre, and Aleid C. J. Ruijs. Changes in fingertip cold-induced vasodilatation (hunting reaction) on acute exposure to altitude. <i>High Alt Med Biol</i>. 25:212-217, 2024. <b><i>Objective:</i></b> Cold-induced vasodilation (CIVD) of the extremities is an interesting part of human physiology. Although the physiology of the CIVD reaction remains unknown, there are indications that hypoxia influences our CIVD reaction. The objective of this study is to measure the influence of acute hypoxia on the CIVD reaction of the fingertips. <b><i>Methods:</i></b> The CIVD reaction was measured using immersion of one hand in a water bath of 0°C in 12 healthy volunteers at low (1,235 m) and high (3,800 m) altitude during 35 minutes. High altitude was reached by a 20-minute cable car ride. Testing was performed indoors (room temperature, 22-25°C) at both altitudes. Data analysis was performed measuring the parameters of the CIVD reaction. Differences were found using the paired Student's <i>t-test</i>. <b><i>Results:</i></b> There was no significant difference in baseline finger temperature, onset time, peak time, and frequency of the CIVD reaction. However, at high altitude, maximum temperature and amplitude were significantly higher, slope was steeper, and minimum temperature was lower. <b><i>Conclusion:</i></b> We did not find evidence for a diminished CIVD reaction at high altitude due to hypoxia.</p>","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":" ","pages":"212-217"},"PeriodicalIF":1.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140911692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Letter to the Editor: When Mountain Sickness Meets COVID-19 Infection: A Rare Ocular Cotton-Wool Spot Presentation. 致编辑的信当登山病遇上 COVID-19 感染:罕见的眼部棉絮斑表现。
IF 1.6 4区 医学
High altitude medicine & biology Pub Date : 2024-09-01 Epub Date: 2024-05-17 DOI: 10.1089/ham.2023.0117
Fei Han, Tao Luo, Xudong Wen, Wei Jiang, Yan Wu, Yubo Li, Pan Long
{"title":"<i>Letter to the Editor:</i> When Mountain Sickness Meets COVID-19 Infection: A Rare Ocular Cotton-Wool Spot Presentation.","authors":"Fei Han, Tao Luo, Xudong Wen, Wei Jiang, Yan Wu, Yubo Li, Pan Long","doi":"10.1089/ham.2023.0117","DOIUrl":"10.1089/ham.2023.0117","url":null,"abstract":"","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":" ","pages":"251-253"},"PeriodicalIF":1.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140955898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Nitric Oxide Ameliorates the Effects of Hypoxia in Mice by Regulating Oxygen Transport by Hemoglobin. 一氧化氮通过调节血红蛋白的氧转运改善小鼠缺氧的影响
IF 1.6 4区 医学
High altitude medicine & biology Pub Date : 2024-09-01 Epub Date: 2024-05-14 DOI: 10.1089/ham.2023.0044
Xiaoying Zhou, Wenting Su, Quanwei Bao, Yu Cui, Xiaoxu Li, Yidong Yang, Chengzhong Yang, Chengyuan Wang, Li Jiao, Dewei Chen, Jian Huang
{"title":"Nitric Oxide Ameliorates the Effects of Hypoxia in Mice by Regulating Oxygen Transport by Hemoglobin.","authors":"Xiaoying Zhou, Wenting Su, Quanwei Bao, Yu Cui, Xiaoxu Li, Yidong Yang, Chengzhong Yang, Chengyuan Wang, Li Jiao, Dewei Chen, Jian Huang","doi":"10.1089/ham.2023.0044","DOIUrl":"10.1089/ham.2023.0044","url":null,"abstract":"<p><p>Xiaoying Zhou, Wenting Su, Quanwei Bao, Yu Cui, Xiaoxu Li, Yidong Yang, Chengzhong Yang, Chengyuan Wang, Li Jiao, Dewei Chen, and Jian Huang. Nitric oxide ameliorates the effects of hypoxia in mice by regulating oxygen transport by hemoglobin. <i>High Alt Med Biol</i>. 25:174-185, 2024.-Hypoxia is a common pathological and physiological phenomenon in ischemia, cancer, and strenuous exercise. Nitric oxide (NO) acts as an endothelium-derived relaxing factor in hypoxic vasodilation and serves as an allosteric regulator of hemoglobin (Hb). However, the ultimate effects of NO on the hematological system <i>in vivo</i> remain unknown, especially in extreme environmental hypoxia. Whether NO regulation of the structure of Hb improves oxygen transport remains unclear. Hence, we examined whether NO altered the oxygen affinity of Hb (Hb-O<sub>2</sub> affinity) to protect extremely hypoxic mice. Mice were exposed to severe hypoxia with various concentrations of NO, and the survival time, exercise capacity, and other physical indexes were recorded. The survival time was prolonged in the 5 ppm NO (6.09 ± 1.29 minutes) and 10 ppm NO (6.39 ± 1.58 minutes) groups compared with the 0 ppm group (4.98 ± 1.23 minutes). Hypoxia of the brain was relieved, and the exercise exhaustion time was prolonged when mice inhaled 20 ppm NO (24.70 ± 6.87 minutes vs. 20.23 ± 6.51 minutes). In addition, the differences in arterial oxygen saturation (SO<sub>2</sub>%) (49.64 ± 7.29% vs. 42.90 ± 4.30%) and arteriovenous SO<sub>2</sub>% difference (25.14 ± 8.95% vs. 18.10 ± 6.90%) obviously increased. In <i>ex vivo</i> experiments, the oxygen equilibrium curve (OEC) left shifted as P50 decreased from 43.77 ± 2.49 mmHg (0 ppm NO) to 40.97 ± 1.40 mmHg (100 ppm NO) and 38.36 ± 2.78 mmHg (200 ppm NO). Furthermore, the Bohr effect of Hb was enhanced by the introduction of 200 ppm NO (-0.72 ± 0.062 vs.-0.65 ± 0.051), possibly allowing Hb to more easily offload oxygen in tissue at lower pH. The crystal structure reveals a greater distance between Asp94β-His146β in nitrosyl -Hb(NO-Hb), NO-HbβCSO93, and S-NitrosoHb(SNO-Hb) compared to tense Hb(T-Hb, 3.7 Å, 4.3 Å, and 5.8 Å respectively, versus 3.5 Å for T-Hb). Moreover, hydrogen bonds were less likely to form, representing a key limitation of relaxed Hb (R-Hb). Upon NO interaction with Hb, hydrogen bonds and salt bridges were less favored, facilitating relaxation. We speculated that NO ameliorated the effects of hypoxia in mice by promoting erythrocyte oxygen loading in the lung and offloading in tissues.</p>","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":" ","pages":"174-185"},"PeriodicalIF":1.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140922133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Clinical Analysis of Myocardial Injury in Highlanders with Pulmonary Hypertension. 肺动脉高压高地人心肌损伤的临床分析
IF 1.6 4区 医学
High altitude medicine & biology Pub Date : 2024-09-01 Epub Date: 2024-06-20 DOI: 10.1089/ham.2023.0075
Maolin Zhao, Qianjin Wu, Wangsheng Duanmu, Junxian Shen, Weixin Yuan, Yingbin Sun, Xu Zhang, Jinbao Zhang, Siyi He
{"title":"Clinical Analysis of Myocardial Injury in Highlanders with Pulmonary Hypertension.","authors":"Maolin Zhao, Qianjin Wu, Wangsheng Duanmu, Junxian Shen, Weixin Yuan, Yingbin Sun, Xu Zhang, Jinbao Zhang, Siyi He","doi":"10.1089/ham.2023.0075","DOIUrl":"10.1089/ham.2023.0075","url":null,"abstract":"<p><p><b><i>Background:</i></b> Pulmonary hypertension (PH) is a prevalent adverse cardiovascular event at high-altitude environments. Prolonged exposure to high altitudes may result in myocardial injury, which is associated with poor clinical outcomes. This study aims to investigate the clinical characteristics of myocardial injury in patients with PH at high altitude. <b><i>Methods:</i></b> Consecutive patients admitted to a general tertiary hospital at the altitude of 3,650 m were selected into this retrospective study. Clinical and biochemical data were collected, as well as based on cardiac troponin I (cTnI) and echocardiography, patients were divided into myocardial injury group and non-myocardial injury group. <b><i>Results:</i></b> A total of 231 patients were enrolled, among whom 29 (12.6%) had myocardial injury. We found that body mass index, left ventricular end-diastolic dimension, and serum level of creatine kinase-MB (CK-MB) in myocardial injury group were significantly higher than non-myocardial injury group. Spearman correlation analysis revealed that cTnI has a significant positive correlation with CK-MB and lactic dehydrogenase instead of aspartate aminotransferase. A receiver operating characteristic curve was drawn to demonstrate that CK-MB could significantly predict the occurrence of myocardial injury with an area under the curve of 0.749, and a level of 3.035 (sensitivity = 59.3%, specificity = 90.5%) was optimal cutoff value. <b><i>Conclusion:</i></b> The incidence of myocardial injury in highlanders with PH is significant. CK-MB, as a convenient and efficient marker, has been found to be closely associated with cTnI and plays a predictive role in the occurrence of myocardial injury with PH in individuals exposed to high altitude.</p>","PeriodicalId":12975,"journal":{"name":"High altitude medicine & biology","volume":" ","pages":"205-211"},"PeriodicalIF":1.6,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141431773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信