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1.
Sci Rep ; 12(1): 9556, 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35688921

RESUMEN

Himalayan ecosystem is characterized by its fragile climate with rich repositories of biodiversity. Waste collection and disposal are becoming increasingly difficult due to topographical variations. Aporrectodea caligenosa, a versatile psychrophillic soil dweller, is a useful biocatalyst with potent bio-augmented capability for waste treatment at low temperatures. Microcosm experiments were conducted to elucidate the comprehensive nature of biogenic nitrogen transformation to NH4+ and NO3- produced by coupling of earthworm-microbes. Higher biogenic recovery of NH4+-N from coprolites of garden soil (47.73 ± 1.16%) and Himalayan goat manure (86.32 ± 0.92%) with an increment of 14.12 and 47.21% respectively over their respective control (without earthworms) with a linear decline beyond 4th week of incubation was reported. NO3--N recovery progressively sustained in garden soil and goat manure coprolites during entire incubation with highest 81.81 ± 0.45 and 87.20 ± 1.08 µg-N g-1dry weight recorded in 6th and 5th week of incubation respectively and peak increments as 38.58 and 53.71% relative to respective control (without earthworms). Declined NH4+-N in coprolites at low temperature (15.0 ± 2.0 °C) evidenced increased nitrification rates by taking over the process by abundant nitrifying microbes. Steady de-nitrification with progressive incubation on an average was 16.95 ± 0.46 ng-N g-1 per week and 21.08 ± 0.87 ng-N g-1 per week compared to 14.03 ± 0.58 ng-N g-1 per week and 4.50 ± 0.31 ng-N g-1 per week in respective control treatments. Simultaneous heterotrophic nitrification and aerobic denitrification (SHNAD) was found to be a prominent bioprocess at low temperature that resulted in high and stable total nitrogen and nitrate accumulation from garden soil and goat manure with relative recovery efficiency of 11.12%, 14.97% and 14.20%; 19.34%. A. caligenosa shows promising prospects for mass applicability in biogenic N removal from manure of Himalayan goat.


Asunto(s)
Nitrógeno , Oligoquetos , Aerobiosis , Altitud , Animales , Desnitrificación , Ecosistema , Procesos Heterotróficos , Estiércol , Nitrificación , Nitrógeno/metabolismo , Oligoquetos/metabolismo , Suelo , Aguas Residuales
3.
Commun Biol ; 5(1): 548, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35668171

RESUMEN

Ascending to high-altitude by non-high-altitude natives is a well-suited model for studying acclimatization to extreme environments. Acute mountain sickness (AMS) is frequently experienced by visitors. The diagnosis of AMS mainly depends on a self-questionnaire, revealing the need for reliable biomarkers for AMS. Here, we profiled 22 AMS symptom phenotypes, 65 clinical indexes, and plasma proteomic profiles of AMS via a combination of proximity extension assay and multiple reaction monitoring of a longitudinal cohort of 53 individuals. We quantified 1069 proteins and validated 102 proteins. Via differential analysis, machine learning, and functional association analyses. We found and validated that RET played an important role in the pathogenesis of AMS. With high-accuracies (AUCs > 0.9) of XGBoost-based models, we prioritized ADAM15, PHGDH, and TRAF2 as protective, predictive, and diagnostic biomarkers, respectively. Our findings shed light on the precision medicine for AMS and the understanding of acclimatization to high-altitude environments.


Asunto(s)
Mal de Altura , Proteínas ADAM , Enfermedad Aguda , Altitud , Mal de Altura/diagnóstico , Biomarcadores , Humanos , Proteínas de la Membrana , Proteómica
4.
Infect Dis Poverty ; 11(1): 66, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35668472

RESUMEN

BACKGROUND: Unsafe drinking water, poor sanitation and hygiene, exposure to household air pollution and low cognitive and socio-emotional stimulation are risk factors affecting children in low- and middle-income countries. We implemented an integrated home-environmental intervention package (IHIP), comprising a kitchen sink, hygiene education and a certified improved biomass cookstove, and an early child development (ECD) programme to improve children´s health and developmental outcomes in the rural high-altitude Andes of Peru. METHODS: We conducted a one-year cluster-randomised controlled trial among 317 children < 36 months divided into 4 arms (IHIP + ECD, IHIP, ECD, and Control) and 40 clusters (10 clusters per arm). ECD status (socio-emotional, fine and gross motor, communication, cognitive skills, and an overall performance) measured with the Peruvian Infant Development Scale and the occurrence of self-reported child diarrhoea from caretakers were primary outcomes. Secondary outcomes included the occurrence of acute respiratory infections and the presence of thermo-tolerant faecal bacteria in drinking water. The trial was powered to compare each intervention against its control arm but it did not allow pairwise comparisons among the four arms. Primary analysis followed the intention-to-treat principle. For the statistical analysis, we employed generalised estimating equation models with robust standard errors and an independent correlation structure. RESULTS: We obtained ECD information from 101 children who received the ECD intervention (individually and combined with IHIP) and 102 controls. Children who received the ECD intervention performed better in all the domains compared to controls. We found differences in the overall performance (64 vs. 39%, odd ratio (OR): 2.8; 95% confidence interval (CI): 1.6-4.9) and the cognitive domain (62 vs 46%, OR: 1.9; 95% CI: 1.1-3.5). Data analysis of child morbidity included 154 children who received the IHIP intervention (individually and combined with ECD) and 156 controls. We recorded 110,666 child-days of information on diarrhoea morbidity and observed 1.3 mean episodes per child-year in the children who received the IHIP intervention and 1.1 episodes in the controls. This corresponded to an incidence risk ratio of 1.2 (95% CI: 0.8-1.7). CONCLUSIONS: Child stimulation improved developmental status in children, but there was no health benefit associated with the home-environmental intervention. Limited year-round access to running water at home and the possible contamination of drinking water after boiling were two potential factors linked to the lack of effect of the home-environmental intervention. Potential interactions between ECD and home-environmental interventions need to be further investigated. TRIAL REGISTRATION: ISRCTN, ISRCTN-26548981. Registered 15 January 2018-Retrospectively registered, https://doi.org/10.1186/ISRCTN26548981 .


Asunto(s)
Salud del Niño , Agua Potable , Altitud , Niño , Desarrollo Infantil/fisiología , Diarrea/epidemiología , Diarrea/prevención & control , Agua Potable/microbiología , Humanos , Lactante , Perú/epidemiología , Población Rural
5.
Pan Afr Med J ; 41: 235, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35721656

RESUMEN

Introduction: visuospatial is a type of high-level visual perception necessary for identification, information integration, analysing of visual and spatial forms, details, structures and spatial relation. These functions are required in order to successfully complete aviation-related tasks, such as analysing movement, distance perception, and spatial navigation. The aim of this study is to examine whether hypobaric hypoxia can significantly influence changes in visuospatial function, thus increasing the risk of accident or serious incident during flight operation. Methods: this study is a quasi-experiment of pre-post study including before and after hypobaric hypoxia simulated through an altitude chamber. In this study, 42 military aircrews were exposed to different altitude zones at ground level, 10,000 ft (ft) and 25,000 ft respectively, for five minutes. At each altitude zone, the participants were instructed to complete a clock drawing test as a measurement for visuospatial function. The results were analysed using the McNemar non-parametric test. Results: among the 42 subjects, six show impaired visuospatial function at 10,000 ft and 26 participants show it at 25,000 ft. There were significant increased on the proportion of impaired visuospatial function between the ground level to 10,000 ft (p=0.031), 10,000 to 25,000 ft (p=0.0001) and ground level to 25,000 ft (p=0.0001). Conclusion: hypobaric hypoxia may have a significant influence on visuospatial function, starting from as early as 10,000 ft to 25,000 ft. This decrease of visuospatial function could affect human cognitive performance when flying and increase the risk of aviation accidents.


Asunto(s)
Medicina Aeroespacial , Aviación , Personal Militar , Altitud , Humanos , Hipoxia
6.
Rev Fac Cien Med Univ Nac Cordoba ; 79(2): 132-140, 2022 06 06.
Artículo en Español | MEDLINE | ID: mdl-35700460

RESUMEN

Introduction: Congenital abnormalities could be caused by copy number variation or homozygous variants inherited of parental consanguineous. Purpose. Objetive: To show copy number variants and regions of homozygosity in neonates with malformative syndrome or one congenital anomaly major associated to facial dysmorphia or hypotonia. Methodology: Performed chromosomal microarray analysis (CGH/SNP) to 60 neonates with congenital anomalies born in Hospital Antonio Lorena and Hospital Regional Cusco. Results: 70% of the newborns had an abnormal test (n=42); 48,3% (n=29) patients had with regions of homozygosity above to 0,5% (endogamy coefficient up to 1/64). Pathogenic or likely pathogenic copy number variations with or without region of homozygosity were present in 14,2% (n=6) newborns with congenital abnormalities. We founded five patients with uncertain pathogenic copy number variations that have not been described previously and might correlate with phenotype. Conclusion: We founded a similar frequency of CNV in newborns with congenital abnormalities compared to previous reports. Nonetheless, parental consanguinity was increased compared to other countries of South America. This is the first report in Peru that showed to CMA as a useful diagnostic method in patients with congenital abnormalities and is pioneer in relation to other countries in Latinoamerica.


Introducción: Las variantes en el número de copias son un tipo de cambios en el genoma provocan anomalías congénitas. Objetivo: Determinar las variantes en el número de copias y el grado de consanguinidad parental en neonatos con síndromes malformativos o una anomalía congénita mayor asociado a dismorfia facial o hipotonía. Materiales y métodos: Se realizó el análisis cromosómico por micromatrices a 60 neonatos con anomalías congénitas evaluados en los Hospitales Antonio Lorena y Regional de Cusco. Resultados: Del total de pacientes estudiados, el 70% tuvo un resultado anómalo; de los cuales en el 14,2% de los recién nacidos se encontraron variantes en el número de copias patogénicas o probablemente patogénicas asociadas o no a regiones de homocigosidad que tuvieron relación con las anomalías congénitas descritas. En el 48,3% de los recién se encontró regiones de homocigosidad mayores a 0,5% (coeficiente de endogamia superior a 1/64). Por otro lado, encontramos cinco variantes en el número de copias de patogenicidad desconocida que no se han descrito anteriormente y podrían estar relacionadas con el fenotipo. Conclusión: Nuestra tasa de detección de las variantes en el número de copias está en relación con los reportes internacionales previos. Sin embargo, el porcentaje de neonatos con consanguinidad parental se encuentra por encima de lo reportado previamente, siendo superior a otras regiones de Sudamerica. Este es el primer reporte en el Perú, y es pionero en Latinoamérica al utilizar el análisis cromosómico por micromatrices en esta cohorte específica de pacientes.


Asunto(s)
Altitud , Variaciones en el Número de Copia de ADN , Consanguinidad , Humanos , Recién Nacido , Padres , Perú , Estudios Retrospectivos
7.
BMJ Open ; 12(6): e057698, 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35701068

RESUMEN

OBJECTIVES: To examine whether a high positive end-expiratory pressure (PEEP ≥5 cmH2O) has a protective effect on the risk of postoperative pulmonary complications (PPCs) in a cohort of patients living at high altitudes and undergoing general anaesthesia. DESIGN: Retrospective, observational study. SETTING: A tertiary hospital in China. PARTICIPANTS: Adult Tibetan patients living at high altitudes (≥3000 m) and who went to the low-altitude plain to undergo non-cardiothoracic surgery under general anaesthesia, from January 2018 to April 2020. MEASUREMENTS: This study included 1905 patients who were divided according to the application of an intraoperative PEEP: low PEEP (<5 cmH2O, including 0 cmH2O) or high PEEP (≥5 cmH2O). The primary outcome was a composite of PPCs within the first 7 postoperative days. The secondary outcomes included reintubation and unplanned intensive care unit (ICU) admission within the first 7 postoperative days and total hospital stays (day). RESULTS: The study included 1032 patients in the low PEEP group and 873 in the high PEEP group. There were no differences in the incidence of PPCs between the high and low PEEP groups (relative risk (RR) 0.913; 95% CI 0.716 to 1.165; p=0.465). After propensity score matching, 643 patients remained in each group, and the incidence of PPCs in the low PEEP group (18.0%) was higher than in the high PEEP group (13.7%; RR 0.720; 95% CI 0.533 to 0.974; p=0.033). There were no differences in the incidence of reintubation, unplanned ICU admission or hospital stays. The risk factors of PPCs derived from multiple regression showed that the application of >5 cmH2O PEEP during intraoperative mechanical ventilation was associated with a significantly lower risk of PPCs in patients from a high altitude (OR=0.725, 95% CI 0.530 to 0.992; p=0.044). CONCLUSIONS: The application of PEEP ≥5 cmH2O during intraoperative mechanical ventilation in patients living at high altitudes and undergoing surgery at low altitudes may be associated with a lower risk of PPCs. Prospective longitudinal studies are needed to further investigate perioperative lung protection ventilation strategies for patients from high altitudes. TRIAL REGISTRATION NUMBER: Chinese Clinical Trial Registry (ChiCTR2100044260).


Asunto(s)
Altitud , Respiración con Presión Positiva , Adulto , Humanos , Pulmón , Respiración con Presión Positiva/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Estudios Prospectivos , Estudios Retrospectivos
8.
Seizure ; 99: 176-177, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35697480
9.
Sci Rep ; 12(1): 9749, 2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35697776

RESUMEN

There are conflicting reports regarding the efficacy of cortisol as a stress marker in altitude training due to the influence of the circadian rhythm. This study aimed to verify whether the automated measurement of salivary cortisol concentration via sequential sampling could detect the differences in exercise stress between two altitudes. We enrolled 12 elite female long-distance runners living near sea level. For the first higher-altitude camp, the runners lived at 1800 m and trained at 1700 m for 7 days. For the second lower-altitude camp, they lived at 1550 m and trained at 1300 m for 7 days. Their saliva was sequentially collected on the last 2 days during each camp which involved different intensity exercises in the morning and afternoon. The salivary cortisol concentrations were measured using electrochemiluminescence immunoassay. Before dinner, the basal salivary cortisol concentrations were significantly higher in the higher-altitude camp. The rate of change in the salivary cortisol concentration during the morning exercise was significantly higher in the higher-altitude camp than in lower-altitude camp (p = 0.028) despite the same exercise programs and intensities. Salivary cortisol level measurements during the athletes' circadian rhythms could detect the differences in acclimatization and exercise stress between two altitudes.


Asunto(s)
Altitud , Carrera , Aclimatación/fisiología , Ritmo Circadiano , Femenino , Humanos , Hidrocortisona , Carrera/fisiología , Saliva
10.
S D Med ; 75(2): 82-87, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35704870

RESUMEN

In rural settings, medically complicated patients may require air transport to facilities that are capable of providing higher levels of care. Extra consideration must be given to pulmonary pathologies when considering this mode of transport. Altitude changes impact both air pressure and volume as described by Boyle's law. These changes can complicate the care of these patients in several ways. We present a case of patient with respiratory failure secondary to viral infection who developed acute bilateral pneumothorax (PTX) while mechanically ventilated during a transport on a fixed-wing aircraft. In this article we outline the unique risks of air travel on the development and progression of PTX as well as the unique challenges with diagnosis and treatment during air transport.


Asunto(s)
Neumotórax , Insuficiencia Respiratoria , Aeronaves , Altitud , Humanos , Lactante , Neumotórax/diagnóstico por imagen , Neumotórax/etiología , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia
11.
Zhonghua Xin Xue Guan Bing Za Zhi ; 50(6): 577-584, 2022 Jun 24.
Artículo en Chino | MEDLINE | ID: mdl-35705467

RESUMEN

Objective: To investigate the gene expression characteristics of peripheral blood mononuclear cells from patients with high altitude pulmonary hypertension (HAPH) in Naxi residents living in Lijiang, Yunnan, and to explore the underlying pathogenesis and value for potential drug selection. Methods: This is a case-control study. Six patients with HPAH (HPAH group) and 4 normal subjects (control group) were selected from the Naxi residents who originally lived in Lijiang, Yunnan Province. The general clinical data of the two groups were collected, and the related indexes of pulmonary artery pressure were collected. Peripheral blood mononuclear cells of the subjects were collected for RNA sequencing. The differences on gene expression, regulatory network of transcription factors and drug similarity between the two groups were compared. The results were compared with the public data of idiopathic pulmonary arterial hypertension (IPAH). Biological processes and signal pathways were analyzed and compared between HPAH and IPAH patients. Results: The age of 6 patients with HAPH was (68.1±8.3) years old, and there were 2 males (2/6). The age of 4 subjects in the control group was (62.3±10.9) years old, and there were 2 males (2/4). Tricuspid regurgitation velocity, tricuspid pressure gradient and pulmonary systolic pressure in HAPH group were significantly higher than those in control group (all P<0.05). The results of RNA sequencing showed that compared with the control group, 174 genes were significantly upregulated and 169 genes were downregulated in peripheral blood mononuclear cells of HAPH group. These differentially expressed genes were associated with 220 biological processes, 52 molecular functions and 23 cell components. A total of 21 biological processes and 2 signal pathways differed between HPAH and IPAH groups, most of which were related to inflammation and immune response. ZNF384, SP1 and STAT3 were selected as highly correlated transcription factors by transcription factor prediction analysis. Trichostatin A and vorinostat were screened out as potential drugs for the treatment of HAPH by drug similarity analysis. Conclusions: There are significant differences in gene expression in peripheral blood monocytes between HAPH patients and normal population, and inflammation and immune dysfunction are the main pathogenic factors. Trichostatin A and Vorinostat are potential drugs for the treatment of HAPH.


Asunto(s)
Leucocitos Mononucleares , Transcriptoma , Anciano , Altitud , Mal de Altura , Estudios de Casos y Controles , China , Hipertensión Pulmonar Primaria Familiar , Humanos , Hipertensión Pulmonar , Inflamación , Masculino , Persona de Mediana Edad , Factores de Transcripción , Vorinostat
12.
Mol Biol Evol ; 39(6)2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35642306

RESUMEN

As the best adapted high altitude population, Tibetans feature a relatively high offspring survival rate. Genome-wide studies have identified hundreds of candidate SNPs related to high altitude adaptation of Tibetans, although most of them have unknown functional relevance. To explore the mechanisms behind successful reproduction at high altitudes, we compared the placental transcriptomes of Tibetans, sea level Hans (SLHan), and Han immigrants (ImHan). Among the three populations, placentas from ImHan showed a hyperactive gene expression pattern. Their increased activation demonstrates a hypoxic stress response similar to sea level individuals experiencing hypoxic conditions. Unlike ImHan, Tibetan placentas were characterized by the significant up-regulation of placenta-specific genes, and the activation of autophagy and the tricarboxylic acid (TCA) cycle. Certain conserved hypoxia response functions, including the antioxidant system and angiogenesis, were activated in both ImHan and Tibetans, but mediated by different genes. The coherence of specific transcriptome features linked to possible genetic contribution was observed in Tibetans. Furthermore, we identified a novel Tibetan-specific EPAS1 isoform with a partial deletion at exon six, which may be involved in the adaption to hypoxia through the EPAS1-centred gene network in the placenta. Overall, our results show that the placenta grants successful pregnancies in Tibetans by strengthening the natural functions of the placenta itself. On the other hand, the placenta of ImHan was in an inhabiting time-dependent acclimatization process representing a common hypoxic stress response pattern.


Asunto(s)
Altitud , Transcriptoma , Aclimatación/genética , Femenino , Hemoglobinas/genética , Humanos , Hipoxia/metabolismo , Placenta/metabolismo , Embarazo , Reproducción , Tibet
13.
Nature ; 606(7914): 565-569, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35650430

RESUMEN

Flowering plants (angiosperms) can grow at extreme altitudes, and have been observed growing as high as 6,400 metres above sea level1,2; however, the molecular mechanisms that enable plant adaptation specifically to altitude are unknown. One distinguishing feature of increasing altitude is a reduction in the partial pressure of oxygen (pO2). Here we investigated the relationship between altitude and oxygen sensing in relation to chlorophyll biosynthesis-which requires molecular oxygen3-and hypoxia-related gene expression. We show that in etiolated seedlings of angiosperm species, steady-state levels of the phototoxic chlorophyll precursor protochlorophyllide are influenced by sensing of atmospheric oxygen concentration. In Arabidopsis thaliana, this is mediated by the PLANT CYSTEINE OXIDASE (PCO) N-degron pathway substrates GROUP VII ETHYLENE RESPONSE FACTOR transcription factors (ERFVIIs). ERFVIIs positively regulate expression of FLUORESCENT IN BLUE LIGHT (FLU), which represses the first committed step of chlorophyll biosynthesis, forming an inactivation complex with tetrapyrrole synthesis enzymes that are negatively regulated by ERFVIIs, thereby suppressing protochlorophyllide. In natural populations representing diverse angiosperm clades, we find oxygen-dependent altitudinal clines for steady-state levels of protochlorophyllide, expression of inactivation complex components and hypoxia-related genes. Finally, A. thaliana accessions from contrasting altitudes display altitude-dependent ERFVII activity and accumulation. We thus identify a mechanism for genetic adaptation to absolute altitude through alteration of the sensitivity of the oxygen-sensing system.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Magnoliopsida , Altitud , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Clorofila/metabolismo , Regulación de la Expresión Génica de las Plantas , Hipoxia , Magnoliopsida/genética , Oxígeno/metabolismo , Protoclorofilida/metabolismo
14.
High Alt Med Biol ; 23(2): 165-172, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35708530

RESUMEN

Heiniger, Grégory, Simon Walbaum, Claudio Sartori, Alban Lovis, Marco Sazzini, Andrew Wellman, and Raphael Heinzer. Altitude-Induced Sleep Apnea Is Highly Dependent on Ethnic Background (Sherpa Vs. Tamang). High Alt Med Biol. 23:165-172, 2022. Rationale: High altitude-induced hypocapnic alkalosis generates central sleep apnea (CSA). In Nepal, two ethnic groups live at medium-to-high altitude: Tamangs originate from low-altitude Tibeto-Burman populations, whereas Sherpas descend from high-altitude Tibetans. Objective: To compare apnea severity at low and high altitude between Sherpas and Tamangs. Methods: Polygraphy recordings, including airflow and oxygen saturation, were performed in Nepal at "low" (2,030 m) and "high" (4,380 m) altitudes. Resting ventilation (V̇E) and mixed-exhaled CO2 (FECO2) were also measured at the same altitudes. Differences in apnea-hypopnea index (AHI), oxygen desaturation index (ODI), and % of nocturnal periodic breathing (NPB) at the two altitudes were compared between ethnicities. Measurements and Main Results: Twenty Sherpas and 20 Tamangs were included (males, median [interquartile range] age: 24.5 [21.5-27.8] years vs. 26.0 [21.5-39.8] years, body mass index: 23.9 [22.1-26.1] kg/m2 vs. 25.21 [20.6-27.6] kg/m2). Compared with Tamangs, Sherpas showed a lower increase in AHI (+7.5 [2.6-17.2]/h vs. +31.5 [18.2-57.3]/h, p < 0.001), ODI (+13.8 [5.5-28.2]/h vs. +42.0 [22.6-77.6]/h, p < 0.001), and NPB proportion (+0.9 [0-3.5]% vs. +12.8 [3.1-27.4]%, p < 0.001) from low to high altitude. Resting V̇E was higher in Sherpas versus Tamangs at both low (8.45 [6.89-10.70] l/min vs. 6.3 [4.9-8.3] l/min, p = 0.005) and high (9.7 [8.5-11] l/min vs. 8.74 [7.39-9.73] l/min, p = 0.020) altitudes, whereas the mean ± standard deviation FECO2 decrease between low and high altitude was greater in Tamangs versus Sherpas (-0.50% ± 0.44% vs. -0.80% ± 0.33%, p < 0.023). Conclusion: Overall, altitude-adapted Sherpas showed a 3.2-times smaller increase in sleep-disordered breathing between low and high altitude compared with Tamangs, and higher ventilation and a smaller drop in FECO2 at high altitude. These data suggest that genetic differences in breathing control can be protective against CSA.


Asunto(s)
Mal de Altura , Síndromes de la Apnea del Sueño , Apnea Central del Sueño , Adulto , Altitud , Dióxido de Carbono , Humanos , Masculino , Oxígeno , Síndromes de la Apnea del Sueño/etiología , Apnea Central del Sueño/etiología , Adulto Joven
15.
High Alt Med Biol ; 23(2): 173-184, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35708531

RESUMEN

Li, Xiao-lin, Wei-gang Wang, Mao-xing Li, Tian-long Liu, Xiu-yu Tian, and Lan Wu. Effects of altitude and duration of differing levels of hypoxic exposure on hypoxia-inducible factor-1α in rat tissues. High Alt Med Biol. 23:173-184, 2022. Objective: This research aimed to evaluate the effects of hypoxia at different altitudes and durations on the expression of hypoxia-inducible factor-1α (HIF-1α) in rat tissues. Methods: A total of 72 Wistar rats were used to investigate the effect of hypoxia at different durations on rat tissues and 72 Wistar rats were used to investigate the effect of hypoxia at different altitudes. Hematoxylin and Eosin (HE) staining was performed to observe the pathological changes of hippocampus tissues, and the expression of HIF-1α of rats under conditions of hypoxia was detected by quantitative real-time polymerase chain reaction and western blotting. Results: According to the pathological results, we found that the degree of the brain, lung, and heart damage and HIF-1α expression, showed an increasing trend as the altitude (1,500, 3,000, 4,500, 6,000, 7,500, and 8,000 m for 12 hours) and duration (0, 6, 12, 24, 36, and 72 hours at 7,500 m) of hypoxia increased. Although there is a significant difference at 8,000 m, considering model stability, animal ethics and cost, we chose 7,500 m as a fixed altitude during hypoxia at different durations. Compared with the normoxic group, the expression of HIF-1α mRNA in the 7,500 m significantly increased by 30.48%, 21.00%, and 12.62%, in brain, lung, and heart tissue (p < 0.01), and HIF-1α mRNA in the 72-hour hypoxic exposure group significantly increased by 52.58%, 20.39%, 27.88% in tissues (p < 0.05). Compared with the normoxic group, HIF-1α protein expressions in the 7,500 m significantly increased by 10.26%, 31.71%, and 13.33% in brain, lung, and heart tissue (p < 0.01, p < 0.01, p < 0.05), and HIF-1α protein expressions in the 72-hour hypoxic exposure group significantly increased by 18.89%, 22.89%, and 29.75% in tissues (p < 0.05). Conclusion: HIF-1α expression in the rat was correlated with altitude and duration of hypoxic exposure.


Asunto(s)
Altitud , Subunidad alfa del Factor 1 Inducible por Hipoxia , Animales , Hipoxia/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Wistar
16.
Front Public Health ; 10: 900539, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35646801

RESUMEN

Objective: To investigate the use of video display terminal (VDT) in high-altitude regions by medical students and the resulted risk factors of eye discomfort. Methods: A cross-sectional study was conducted in 686 medical students randomly selected from high-altitude regions, Kunming, Yunnan Province. The prevalence of video display terminal syndrome (VDTs) and related risk factors in medical students were analyzed by instructing students to fill in the eye discomfort symptom questionnaire [Ocular Surface Disease Index (OSDI) scale]. Results: There were 686 participants in this study, including 213 males (31.0%) and 473 females (69.0%). The results of questionnaire survey showed that 184 patients (26.8%) didn't have eye discomfort symptoms and 502 patients (73.2%) had eye discomfort symptoms. The comparison of demographic and ocular characteristics of eye discomfort symptoms group and no eye discomfort symptoms group showed that medical students in the group with ocular discomfort symptoms had longer total duration of video terminal use, longer duration of each VDT use, higher total scores of ocular discomfort symptom scores, and a higher percentage of the ocular discomfort severity group, all with statistically significant differences. There was no significant difference in the remaining parameters between the two groups of participants. The results of multivariate logistic regression model analysis showed that the relationship between total sleep time, total duration of VDT use and eye discomfort symptom score was statistically significant (P < 0.05). Besides, ordinal logistic regression was applied further to investigate related factors of the severity of eye discomfort. The model demonstrated that total sleep duration and total VDT using duration were significantly associated with the severity of eye discomfort symptom (P < 0.05).The severity of eye discomfort symptom was significantly negatively related to the increased total sleep duration and it was significantly positively related to the increased VDT use duration. Conclusion: The prevalence of VDTs is high in medical students at high-altitude regions. The longer total duration of daily use of VDT and shorter sleep duration are risk factors associated with VDTs. The severity of eye discomfort symptom was significantly negatively related to the increased total sleep duration and it was significantly positively related to the increased total VDT using duration.


Asunto(s)
Oftalmopatías , Enfermedades Profesionales , Estudiantes de Medicina , Altitud , China/epidemiología , Terminales de Computador , Estudios Transversales , Oftalmopatías/epidemiología , Oftalmopatías/etiología , Femenino , Humanos , Masculino , Enfermedades Profesionales/complicaciones , Enfermedades Profesionales/epidemiología
17.
FASEB J ; 36(7): e22391, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35661419

RESUMEN

Aerobic energy demands have led to the evolution of complex mitochondrial reticula in highly oxidative muscles, but the extent to which metabolic challenges can be met with adaptive changes in physiology of specific mitochondrial fractions remains unresolved. We examined mitochondrial mechanisms supporting adaptive increases in aerobic performance in deer mice (Peromyscus maniculatus) adapted to the hypoxic environment at high altitude. High-altitude and low-altitude mice were born and raised in captivity, and exposed as adults to normoxia or hypobaric hypoxia (12 kPa O2 for 6-8 weeks). Subsarcolemmal and intermyofibrillar mitochondria were isolated from the gastrocnemius, and a comprehensive substrate titration protocol was used to examine mitochondrial physiology and O2  kinetics by high-resolution respirometry and fluorometry. High-altitude mice had greater yield, respiratory capacity for oxidative phosphorylation, and O2 affinity (lower P50 ) of subsarcolemmal mitochondria compared to low-altitude mice across environments, but there were no species difference in these traits in intermyofibrillar mitochondria. High-altitude mice also had greater capacities of complex II relative to complexes I + II and higher succinate dehydrogenase activities in both mitochondrial fractions. Exposure to chronic hypoxia reduced reactive oxygen species (ROS) emission in high-altitude mice but not in low-altitude mice. Our findings suggest that functional changes in subsarcolemmal mitochondria contribute to improving aerobic performance in hypoxia in high-altitude deer mice. Therefore, physiological variation in specific mitochondrial fractions can help overcome the metabolic challenges of life at high altitude.


Asunto(s)
Altitud , Peromyscus , Animales , Hipoxia , Mitocondrias , Mitocondrias Musculares , Músculo Esquelético , Peromyscus/fisiología
18.
Artículo en Inglés | MEDLINE | ID: mdl-35564444

RESUMEN

Meaningful, positive, emotional and challenging adventurous activities may generate personal growth or recovery from ill health or injury. In this study, we used a distinctive longitudinal and immersive research approach to explore the psychological impact of a high-altitude expedition to the Nepalese Himalaya on 10 (9 males) UK military veterans with longstanding well-being concerns. In the 12 months prior to the expedition, participants took part in three training weekends in the UK mountains. During the expedition, instructors-who were all experienced health coaches-facilitated reflective practices with the beneficiaries throughout, focusing on experiential transfer to day-to-day lives after the expedition. Follow-up interviews, conducted up to 18-months post-expedition, identified that the most desirable changes aligned with the three innate psychological needs of self-determination theory: autonomy, competence and relatedness. The routines established during the preparation stage and during the expedition itself activated a renewed energy for personal improvement. At 18 months post-expedition, the key changes reflected altered perspective, employment skills and work-life balance, increased physical activity and enhanced personal awareness and mindfulness. Importantly, supported by regular health coaching and focused on the transfer of learning, expeditions can activate meaningful long-term changes to the well-being and personal development of military veterans.


Asunto(s)
Expediciones , Montañismo , Veteranos , Altitud , Humanos , Masculino , Montañismo/fisiología , Reino Unido
19.
Sci Total Environ ; 838(Pt 1): 155615, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-35508230

RESUMEN

Due to the gradual phase-out of brominated flame retardants, the consumption of organophosphate esters (OPEs) as suitable alternatives has increased in recent years. These compounds could be trapped and accumulate in the widely developed glaciers such as Laohugou Glacier No. 12 in the Tibetan Plateau (TP), as snow is an effective scavenger of organic pollutants in the atmosphere. However, large gaps in knowledge still exist regarding the occurrence, distribution, and source analysis of OPEs in TP glaciers. In this study, eight surface snow samples collected at different altitudes on Laohugou Glacier No. 12 on the northeastern edge of the TP in order to investigate sources and distribution of OPEs. The results showed that the concentrations of ∑7OPEs varied from 54.53 ng/L to 169.15 ng/L, with a mean of 99.84 ng/L. ∑Chlorinated-OPEs (Cl-OPEs) were dominant in these samples, accounting for 83% of the total OPE concentrations. ∑OPEs concentration increases with altitude on Laohugou Glacier No. 12, implying an altitudinal magnification effect on OPEs deposition. Principal component analysis suggests that OPEs primarily originated from traffic emissions and their variations were largely driven by dust transport. Analyses of backward trajectories of air masses and the wind field indicate that these OPEs might have come from urban emissions northwest of Laohugou Glacier No. 12. This study provides the first valuable insight into the environmental behavior of OPEs in Tibetan glaciers.


Asunto(s)
Retardadores de Llama , Nieve , Altitud , China , Monitoreo del Ambiente , Ésteres/análisis , Retardadores de Llama/análisis , Organofosfatos/análisis , Tibet
20.
J Exp Biol ; 225(12)2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35552735

RESUMEN

Highland native deer mice (Peromyscus maniculatus) have greater rates of lipid oxidation during maximal cold challenge in hypoxia (hypoxic cold-induced V̇O2,max) compared with their lowland conspecifics. Lipid oxidation is also increased in deer mice acclimated to simulated high altitude (cold hypoxia), regardless of altitude ancestry. The underlying lipid metabolic pathway traits responsible for sustaining maximal thermogenic demand in deer mice is currently unknown. The objective of this study was to characterize key steps in the lipid oxidation pathway in highland and lowland deer mice acclimated to control (23°C, 21 kPa O2) or cold hypoxic (5°C, 12 kPa O2) conditions. We hypothesized that capacities for lipid delivery and tissue uptake will be greater in highlanders and further increase with cold hypoxia acclimation. With the transition from rest to hypoxic cold-induced V̇O2,max, both highland and lowland deer mice showed increased plasma glycerol concentrations and fatty acid availability. Interestingly, acclimation to cold hypoxia led to increased plasma triglyceride concentrations at cold-induced V̇O2,max, but only in highlanders. Highlanders also had significantly greater delivery rates of circulatory free fatty acids and triglycerides due to higher plasma flow rates at cold-induced V̇O2,max. We found no population or acclimation differences in fatty acid translocase (FAT/CD36) abundance in the gastrocnemius or brown adipose tissue, suggesting that fatty acid uptake across membranes is not limiting during thermogenesis. Our data indicate that circulatory lipid delivery plays a major role in supporting the high thermogenic rates observed in highland versus lowland deer mice.


Asunto(s)
Consumo de Oxígeno , Peromyscus , Aclimatación , Altitud , Animales , Frío , Ácidos Grasos , Hipoxia , Termogénesis , Triglicéridos
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