Assessment of metabolomic variations among individuals returning to plain areas after exposure to high altitudes: a metabolomic analysis of human plasma samples with high-altitude de-acclimatization syndrome.

Background: High altitude de-acclimatization (HADA) is gradually becoming a public health concern as millions of individuals of different occupations migrate to high-altitude areas for work due to economic growth in plateau areas. HADA affects people who return to lower elevations after exposure to high altitudes. It causes significant physiological and functional changes that can negatively impact health and even endanger life. However, uncertainties persist about the detailed mechanisms underlying HADA. Methods: We established a population cohort of individuals with HADA and assessed variations in metabolite composition. Plasm samples of four groups, including subjects staying at plain (P) and high altitude (H) as well as subjects suffering from HADA syndrome with almost no reaction (r3) and mild-to-moderate reaction (R3) after returning to plain from high altitude, were collected and analyzed by Liquid Chromatography-Mass Spectrometry metabolomic. Multivariate statistical analyses were used to explore significant differences and potential clinical prospect of metabolites. Result: Although significantly different on current HADAS diagnostic symptom score, there were no differences in 17 usual clinical indices between r3 and R3. Further multivariate analyses showed isolated clustering distribution of the metabolites among the four groups, suggesting significant differences in their metabolic characteristics. Through K-means clustering analysis, we identified 235 metabolites that exhibited patterns of abundance change consistent with phenotype of HADA syndrome. Pathway enrichment analysis indicated a high influence of polyunsaturated fatty acids under high-altitude conditions. We compared the metabolites between R3 and r3 and found 107 metabolites with differential abundance involved in lipid metabolism and oxidation, suggesting their potential role in the regulation of oxidative stress homeostasis. Among them, four metabolites might play a key role in the occurrence of HADA, including 11-beta-hydroxyandrosterone-3-glucuronide, 5-methoxyindoleacetate, 9,10-epoxyoctadecenoic acid, and PysoPC (20:5). Conclusion: We observed the dynamic variation in the metabolic process of HADA. Levels of four metabolites, which might be provoking HADA mediated through lipid metabolism and oxidation, were expected to be explore prospective indices for HADA. Additionally, metabolomics was more efficient in identifying environmental risk factors than clinical examination when dramatic metabolic disturbances underlying the difference in symptoms were detected, providing new insights into the molecular mechanisms of HADAS.

The making of the Homo Polaris: human acclimatization to the Arctic environment and Soviet ideologies in Northern Medical Institutions.

This paper examines the history of the Soviet human acclimatization project in the North and Siberia, which spanned from medical experiments in Stalin's forced labor camps to the subsequent wave of industrialization in the region. The author argues that human acclimatization in the North was a settler colonial science project aimed at facilitating Russian administrators and engineers in asserting control over the territory and its resources, while creating a new homogeneous 'indigenous population' in Siberia and the North. This envisioned population, referred to as Homo Polaris by the author, was intended to emerge through a two-way transformation: the adaptation of Indigenous peoples into Soviet ideologies and practices, and the acclimatization of settlers coming from the European part of the country to the Arctic environment. Although the administrators and medical doctors were unable to achieve this biopolitical objective, the complexities and dialogues surrounding these transformations shed light on the late Soviet settler-colonial ideologies and their impact on social life in Siberia from the 1950s to the 1980s. The research is based on a comprehensive analysis of both published and archival works by scholars involved in the project.

Effectiveness of Continuous Positive Airway Pressure in Alleviating Hypoxemia and Improving Exertional Capacity at Altitude.

Strickland, Brian, Elan Small, Mary Ryan, and Ryan Paterson. Effectiveness of continuous positive airway pressure in alleviating hypoxemia and improving exertional capacity at altitude. High Alt Med Biol. 00:000-000, 2024. Introduction: Decreased oxygen saturation and exercise tolerance are commonly experienced at high altitude. Continuous positive airway pressure (CPAP) devices have become increasingly portable and battery powered, providing a potentially unique new therapeutic modality for treatment of altitude-related illnesses. This study evaluated the potential use of CPAP devices to improve and maintain oxygen saturation at altitude, both at rest and with exertion, to evaluate the feasibility of using this device at altitude. Methods: Subjects were taken to Mount Blue Sky and monitored while they hiked to the summit (4,350 m), maintaining a consistent level of exertion. Subjects hiked for 0.7 km both with and without CPAP set to 10 cmH2O pressure. Continuous vital signs were collected during the hike and recovery period. Results: All subjects completed the hike wearing CPAP devices at a vigorous level of exertion. Mean oxygen saturation of the CPAP group (M = 83.8%, SD = 3.72) was significantly higher than that of the control group during exertion (M = 78.7%, SD = 2.97); p = 0.005. Recovery after exertion was quicker in the CPAP group than the control group. Three subjects experienced claustrophobia requiring a brief pause, but were able to complete their exercise trial without removing equipment or experiencing adverse events. When pauses from claustrophobia were excluded, there was no difference in completion time between the groups (p = 0.06). Conclusion: CPAP reliably improved oxygen saturation at rest and during vigorous exertion at high altitude. Its ability to correct hypoxemia, even with physical exertion, may prove useful after further study as a portable self-carried device to prevent and treat altitude-related illness, or to improve safety in high-altitude rescues.

An Introduction to Plant Cell, Tissue, and Organ Culture: Current Status and Perspectives.

Plant cell, tissue, and organ cultures (PCTOC) have been used as experimental systems in basic research, allowing gene function demonstration through gene overexpression or repression and investigating the processes involved in embryogenesis and organogenesis or those related to the potential production of secondary metabolites, among others. On the other hand, PCTOC has also been applied at the commercial level for the vegetative multiplication (micropropagation) of diverse plant species, mainly ornamentals but also horticultural crops such as potato or fruit and tree species, and to produce high-quality disease-free plants. Moreover, PCTOC protocols are important auxiliary systems in crop breeding crops to generate pure lines (homozygous) to produce hybrids for the obtention of polyploid plants with higher yields or better performance. PCTOC has been utilized to preserve and conserve the germplasm of different crops or threatened species. Plant genetic improvement through genetic engineering and genome editing has been only possible thanks to the establishment of efficient in vitro plant regeneration protocols. Different companies currently focus on commercializing plant secondary metabolites with interesting biological activities using in vitro PCTOC. The impact of omics on PCTOC is discussed.

Protocol for the Acclimatization of Coconut Vitro-Plants Under Ex Vitro Conditions.

The coconut tree is a crop widely distributed in more than 90 countries worldwide. It has a high economic value derived from the large number of products obtained from the plant, with fast-growing global markets for some of them. Unfortunately, coconut production is decreasing mainly due to the old age of the plants and devastating pests and diseases, such as phytoplasma disease lethal yellowing (LY). Massive replanting is required with phytoplasma-resistant and high-yielding selected coconut plants to keep up with the market demand for fruit. For this purpose, an efficient micropropagation technology via somatic embryogenesis has been established at CICY, yielding fully developed vitro-plants grown within an in vitro environment. Hence, the last stage of the micropropagation process is the acclimatization of the vitro-plants, which are gradually adapted to live in external conditions outside the glass container and the growth room. A protocol has been developed at CICY to acclimate the coconut vitro-plants, and close to 80% survival can be obtained. This protocol is described here.

Scale-Up of Coffea canephora Somatic Embryogenesis in Temporary Immersion System.

Somatic embryogenesis (SE) is a clear example of cellular totipotency. The SE of the genus Coffea has become a model for in vitro propagation for woody species and for the large-scale production of disease-free plants that provide an advantage for modern agriculture. Temporary immersion systems (TIS) are in high demand for the propagation of plants. The success of this type of bioreactor is based on the alternating cycles of immersion of the plant material in the culture medium, usually a few minutes, and the permanence outside the medium of the tissues for several hours. Some bioreactors are very efficient for propagating one species but not another. The efficiency of bioreactors depends on the species, the tissue used to propagate, the species' nutritional needs, the amount of ethylene produced by the tissue, and many more. In this protocol, we show how we produce C. canephora plants that are being taken to the field.

The Importance of Maintaining and Improving a Healthy Gut Microbiota in Athletes as a Preventive Strategy to Improve Heat Tolerance and Acclimatization.

Exposure to passive heat (acclimation) and exercise under hot conditions (acclimatization), known as heat acclimation (HA), are methods that athletes include in their routines to promote faster recovery and enhance physiological adaptations and performance under hot conditions. Despite the potential positive effects of HA on health and physical performance in the heat, these stimuli can negatively affect gut health, impairing its functionality and contributing to gut dysbiosis. Blood redistribution to active muscles and peripheral vascularization exist during exercise and HA stimulus, promoting intestinal ischemia. Gastrointestinal ischemia can impair intestinal permeability and aggravate systemic endotoxemia in athletes during exercise. Systemic endotoxemia elevates the immune system as an inflammatory responses in athletes, impairing their adaptive capacity to exercise and their HA tolerance. Better gut microbiota health could benefit exercise performance and heat tolerance in athletes. This article suggests that: (1) the intestinal modifications induced by heat stress (HS), leading to dysbiosis and altered intestinal permeability in athletes, can decrease health, and (2) a previously acquired microbial dysbiosis and/or leaky gut condition in the athlete can negatively exacerbate the systemic effects of HA. Maintaining or improving the healthy gut microbiota in athletes can positively regulate the intestinal permeability, reduce endotoxemic levels, and control the systemic inflammatory response. In conclusion, strategies based on positive daily habits (nutrition, probiotics, hydration, chronoregulation, etc.) and preventing microbial dysbiosis can minimize the potentially undesired effects of applying HA, favoring thermotolerance and performance enhancement in athletes.

The AaERF64-AaTPPA module participates in cold acclimatization of Actinidia arguta (Sieb. et Zucc.) Planch ex Miq.

Actinidia arguta (A. arguta, kiwiberry) is a perennial deciduous vine with a strong overwintering ability. We hypothesized that trehalose metabolism, which plays a pivotal role in the stress tolerance of plants, may be involved in the cold acclimatization of A. arguta. Transcriptome analysis showed that the expression of AaTPPA, which encodes a trehalose-6-phosphate phosphatase (TPP), was upregulated in response to low temperatures. AaTPPA expression levels were much higher in lateral buds, roots, and stem cambia than in leaves in autumn. In AaTPPA-overexpressing (OE) Arabidopsis thaliana (A. thaliana), trehalose levels were 8-11 times higher than that of the wild type (WT) and showed different phenotypic characteristics from WT and OtsB (Escherichia coli TPP) overexpressing lines. AaTPPA-OE A. thaliana exhibited significantly higher freezing tolerance than WT and OtsB-OE lines. Transient overexpression of AaTPPA in A. arguta leaves increased the scavenging ability of reactive oxygen species (ROS) and the soluble sugar and proline contents. AaERF64, an ethylene-responsive transcription factor, was induced by ethylene treatment and bound to the GCC-box of the AaTPPA promoter to activate its expression. AaTPPA expression was also induced by abscisic acid. In summary, the temperature decrease in autumn is likely to induce AaERF64 expression through an ethylene-dependent pathway, which consequently upregulates AaTPPA expression, leading to the accumulation of osmotic protectants such as soluble sugars and proline in the overwintering tissues of A. arguta. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01475-8.

Comprehensive identification, characterization and expression analysis of genes underpinning heat acclimatization in Triticum durum and Aegilops tauschii.

Wheat (Triticum aestivum L.) is an important cereal crop cultivated and consumed worldwide. Global warming-induced escalation of temperature during the seedling and grain-filling phase adversely affects productivity. To survive under elevated temperatures, most crop plants develop natural mechanisms at molecular level by activating heat shock proteins. However, other heat stress-related proteins like heat acclimatization (HA) proteins are documented in hexaploid wheat but have not been explored in detail in its diploid and tetraploid progenitors, which might help to overcome elevated temperature regimes for short periods. Our study aims to explore the potential HA genes in progenitors Triticum durum and Aegilops tauschii that perform well at higher temperatures. Seven genes were identified and phylogenetically classified into three families: K homology (KH), Chloroplast protein-enhancing stress tolerance (CEST), and heat-stress-associated 32 kDa (HSA32). Protein-protein interaction network revealed partner proteins that aid mRNA translation, protein refolding, and reactive species detoxification. Syntenic analysis displayed highly conserved relationships. RT-qPCR-based expression profiling revealed HA genes to exhibit diverse and dynamic patterns under high-temperature regimes, suggesting their critical role in providing tolerance to heat stress. The present study furnishes genetic landscape of HA genes that might help in developing climate-resilient wheat with higher acclimatization potential.

Contributions of Griffith Pugh to Success on Mt. Everest and His Impact on the Advancement of Altitude and Environmental Physiology.

Griffith Pugh, MD (1909-1994), was a pioneer in altitude physiology. During World War II, he developed training protocols in Lebanon to improve soldier performance at altitude and in the cold. In 1951 he was chosen to join the British Everest team as a scientist. In preparation, he developed strategies for success on a training expedition on Cho Oyu in 1952. Results from Cho Oyu led to the use of supplemental oxygen at higher flow rates during ascent than used previously (4 L/min vs 2 L/min) and continued use (at a reduced rate of 2 L/min) during descent, enabling increased performance and improved mental acuity. Oxygen was also used during sleep, leading to improved sleep and warmth. Adequate hydration (∼3 L/day) was also stressed, and a more appealing diet led to improved nutrition and condition of the climbers. Improved hygiene practices and acclimatization protocols were also developed. These strategies contributed to the first successful summiting of Mount Everest in 1953. Pugh was then appointed as the lead scientist for a ground-breaking eight-and-a-half-month research expedition where the team was the first to overwinter at high altitude (5800 m) in the Himalayas. This current work summarizes Pugh's scientific contributions as they relate to success on Mount Everest and in inspiring future altitude research by generations of successful researchers.

Living in Western Australia induces some physiological adaptations of seasonal acclimatisation in the surgical burns team.

Seasonal acclimatization is known to result in adaptations that can improve heat tolerance. Staff who operate on burn injuries are exposed to thermally stressful conditions and seasonal acclimatization may improve their thermoeffector responses during surgery. Therefore, the aim of this study was to assess the physiological and perceptual responses of staff who operate on burn injuries during summer and winter, to determine whether they become acclimatized to the heated operating theater. Eight staff members had physiological and perceptual responses compared during burn surgeries conducted in thermoneutral (CON: 24.1 ± 1.2°C, 45 ± 7% relative humidity [RH]) and heated (HOT: 31.3 ± 1.6°C, 44 ± 7% RH) operating theaters, in summer and winter. Physiological parameters that were assessed included core temperature, heart rate, total sweat loss, sweat rate, and urinary specific gravity. Perceptual responses included ratings of thermal sensation and comfort. In summer, CON compared to winter CON, baseline (85 ± 15 bpm VS 94 ± 18 bpm), mean (84 ± 16 bpm VS 93 ± 18 bpm), and peak HR (94 ± 17 bpm VS 105 ± 19 bpm) were lower (p < 0.05), whereas core temperature was not different between seasons in either condition (p > 0.05). In HOT, ratings of discomfort were higher in summer (15 ± 3) than winter (13 ± 3; p > 0.05), but ratings of thermal sensation and sweat rate were similar between seasons (p > 0.05). The surgical team in burns in Western Australia can obtain some of the physiological adaptations that result from seasonal acclimatization, but not all. That is most likely due to a lower than required amount of outdoor heat exposure in summer, to induce all physiological and perceptual adaptations.

Roles of eyestalk in salinity acclimatization of mud crab (Scylla paramamosain) by transcriptomic analysis.

Salinity acclimatization refers to the physiological and behavioral adjustments made by crustaceans to adapt to varying salinity environments. The eyestalk, a neuroendocrine organ in crustaceans, plays a crucial role in salinity acclimatization. To elucidate the molecular mechanisms underlying eyestalk involvement in mud crab (Scylla paramamosain) acclimatization, we employed RNA-seq technology to analyze transcriptomic changes in the eyestalk under low (5 ppt) and standard (23 ppt) salinity conditions. This analysis revealed 5431 differentially expressed genes (DEGs), with 2372 upregulated and 3059 downregulated. Notably, these DEGs were enriched in crucial biological pathways like metabolism, osmoregulation, and signal transduction. To validate the RNA-seq data, we further analyzed 15 DEGs of interest using qRT-PCR. Our results suggest a multifaceted role for the eyestalk: maintaining energy homeostasis, regulating hormone synthesis and release, PKA activity, and downstream signaling, and ensuring proper ion and osmotic balance. Furthermore, our findings indicate that the crustacean hyperglycemic hormone (CHH) may function as a key regulator, modulating carbonic anhydrase expression through the activation of the PKA signaling pathway, thereby influencing cellular osmoregulation, and associated metabolic processes. Overall, our study provides valuable insights into unraveling the molecular mechanisms of mud crab acclimatization to low salinity environments.

Explaining the Educational Needs of Iranian First-Time Parents for Adaptation to Parental Role: A Qualitative Study.

Background: The transition to parenthood is one of the most challenging experiences in a couple's life, which can be stressful and difficult. A positive transition period affects the quality of parents' behavior and the baby's health. This qualitative study aimed to explain the educational needs of adaptation to parental role among first-time parents in Iran. Materials and Methods: In this qualitative study, 25 participants from a variety of ethnic backgrounds were recruited in Ahvaz, Iran, using purposive sampling. In-depth interviews were used to collect the data which were analyzed by qualitative content analysis. Results: Three main categories emerged from the data analysis: "The need for knowledge improvement training," "The need for psychological adaptation training," and "The need for sociocultural adaptation training." Conclusions: To adapt to the parental role, first-time parents should be equipped with the knowledge to turn the challenges of this period into an opportunity for growth. Moreover, they need to be supported by their family members, the healthcare team, and the government.

Impact of high-altitude acclimatization and de-acclimatization on the intestinal microbiota of rats in a natural high-altitude environment.

Introduction: Intestinal microorganisms play an important role in the health of both humans and animals, with their composition being influenced by changes in the host's environment. Methods: We evaluated the longitudinal changes in the fecal microbial community of rats at different altitudes across various time points. Rats were airlifted to high altitude (3,650 m) and acclimatized for 42 days (HAC), before being by airlifted back to low altitude (500 m) and de-acclimatized for 28 days (HADA); meanwhile, the control group included rats living at low altitude (500 m; LA). We investigated changes in the gut microbiota at 12 time points during high-altitude acclimatization and de-acclimatization, employing 16S rRNA gene sequencing technology alongside physiological indices, such as weight and daily autonomous activity time. Results: A significant increase in the Chao1 index was observed on day 14 in the HAC and HADA groups compared to that in the LA group, indicating clear differences in species richness. Moreover, the principal coordinate analysis revealed that the bacterial community structures of HAC and HADA differed from those in LA. Long-term high-altitude acclimatization and de- acclimatization resulted in the reduced abundance of the probiotic Lactobacillus. Altitude and age significantly influenced intestinal microbiota composition, with changes in ambient oxygen content and atmospheric partial pressure being considered key causal factors of altitude-dependent alterations in microbiota composition. High-altitude may be linked to an increase in anaerobic bacterial abundance and a decrease in non-anaerobic bacterial abundance. Discussion: In this study, the hypobaric hypoxic conditions at high-altitude increased the abundance of anaerobes, while reducing the abundance of probiotics; these changes in bacterial community structure may, ultimately, affect host health. Overall, gaining a comprehensive understanding of the intestinal microbiota alterations during high-altitude acclimatization and de-acclimatization is essential for the development of effective prevention and treatment strategies to better protect the health of individuals traveling between high- and low-altitude areas.

Changes in hypoxic and hypercapnic ventilatory responses at high altitude measured using rebreathing methods.

Ventilatory responses to hypoxia and hypercapnia play a vital role in maintaining gas exchange homeostasis, and in adaptation to high-altitude environments. This study investigates the mechanisms underlying sensitization of hypoxic and hypercapnic ventilatory responses (HVR and HCVR, respectively) in individuals acclimatized to moderate high altitude (3800 m). Thirty-one participants underwent chemoreflex testing using the Duffin modified rebreathing technique. Measures were taken at sea level and after 2 days of acclimatization to high altitude. Ventilatory recruitment thresholds (VRT), HCVR, and HVR were quantified. Acclimatization to high altitude resulted in increased HVR (p<0.001) and HCVR (p<0.001), as expected. We also observed that the decrease in VRT under hypoxic test conditions significantly contributed to the elevated HVR at high altitude since the change in VRT across hyperoxic and hypoxic test conditions was greater at high altitude compared to baseline sea level tests (p=0.043). Pre-VRT ventilation also increased at high altitude (p<0.001), but the change did not differ between oxygen conditions. Taken together, this data suggests that the increase in HVR at high altitude is at least partially driven by a larger decrease in the VRT in hypoxia versus hyperoxia at high altitude compared to sea level. This study highlights the intricacies of respiratory adaptations during acclimatization to moderate high altitude, shedding light on the roles of the VRT, baseline respiratory drive, and two-slope HCVR in this process. These findings contribute to our understanding of how the human respiratory control responds to hypoxic and hypercapnic challenges at high altitude.

In Vitro Shoot Multiplication and Rooting of 'Kashan' and 'Hervy Azerbaijan' Damask Rose (Rosa damascena Mill.) Genotypes for Cosmetic and Ornamental Applications.

The damask rose (Rosa damascena Mill.) is an ornamental-medicinal plant from the Rosaceae family, and its aromatic compounds and essential oils are applied globally in the food, cosmetic, and pharmaceutical industries. Due to its economic value, this research aimed to establish a protocol for an efficient, rapid, and cost-effective method for in vitro shoot multiplication and rooting of the R. damascena 'Kashan' and 'Hervy Azerbaijan' genotypes. Nodal segments (as primary explants) were cultured on the Murashige and Skoog (MS) medium with combinations of various plant growth regulators (PGRs) such as gibberellic acid (GA3), 6-benzylaminopurine (BAP), and indole-3-butyric acid (IBA), as well as a PGR-like substance, phloroglucinol (PG), vitamins such as ascorbic acid (AA), and activated carbon in the form of active charcoal (AC). For the establishment stage, 0.1 mg·L-1 PG, 0.2 mg·L-1 GA3, and 1 mg·L-1 BAP were added to the media. Secondary explants (nodal segments containing axillary buds produced from primary explants) were obtained after 30 days of in vitro culture and transferred to the proliferation media supplemented with different concentrations of BAP (0, 0.5, 1, 1.5, 2, and 2.5 mg·L-1) and GA3 (0, 0.1, 0.2, 0.4, 0.8, and 1 mg·L-1) together with 0.1 mg·L-1 PG and 20 mg·L-1 of AA. The rooting media were augmented with different concentrations of BAP and GA3 with 0.1 mg·L-1 of IBA, PG and 20 mg·L-1 of AA and AC. The results showed that the highest regeneration coefficient (4.29 and 4.28) and the largest number of leaves (23.33-24.33) were obtained in the explants grown on the medium supplemented with 2 mg·L-1 BAP and 0.4 mg·L-1 GA3 for the 'Kashan' and 'Hervy Azerbaijan' genotypes, respectively. Likewise, this PGR combination provided the shortest time until bud break (approximately 6.5 days) and root emergence (approximately 10 days) in both genotypes. The highest number of shoots (4.78 per explant) and roots (3.96) was achieved in this medium in the 'Kashan' rose. Stem and root lengths, as well as stem and root fresh and dry weights, were also analyzed. In most measured traits, the lowest values were found in the PGRs-free control medium. Rooted plantlets were transferred to pots filled with perlite and peat moss in a 2:1 proportion and were acclimatized to ambient greenhouse conditions with a mean 90.12% survival rate. This research contributes significantly to our understanding of Damask rose propagation and has practical implications for the cosmetic and ornamental plant industries. By offering insights into the manipulation of regeneration processes, our study opens up new possibilities for the effective production of high-quality plant material.

Micropropagation and Genetic Fidelity of Fegra Fig (Ficus palmata Forssk.) and Grafting Compatibility of the Regenerated Plants with Ficus carica.

Ficus palmata is an important fig species that produces edible and nutritious fruit and possesses several therapeutic uses. This study reports an effective method for the micropropagation of F. palmata using nodal explants. In vitro shoots were cultured for 7 weeks onto MS medium fortified with different concentrations of cytokinins, light intensities, sucrose concentrations, and light/dark incubation treatments. Optimal axillary shoot proliferation (10.9 shoots per explant) was obtained on a medium containing 30 g/L sucrose and supplemented with 2 mg/L 6-benzylaminopurine (BAP) under 35 µmol/m2/s light intensity. Dark incubation limited the foliage growth but favored shoot elongation and rooting compared with light incubation. Elongated shoots, under dark conditions, were rooted (100%; 6.67 roots per explant) onto MS medium containing 1 mg/L indole-3-acetic acid (IAA) and 1.5 g/L activated charcoal. The micropropagated plantlets were acclimatized with a 95% survival rate. In this study, the genetic fidelity of micropropagated F. palmata clones along with their mother plant was tested using randomly amplified polymorphic DNA (RAPD), inter-simple sequence repeats (ISSR), and start codon targeted (SCoT) molecular markers. The genetic similarity between the micropropagated plantlets and the mother plant of F. palmata was nearly 95.9%, assuring high uniformity and true-to-type regenerated plants. Using micropropagated F. palmata plantlets as a rootstock proved appropriate for the grafting F. carica 'Brown Turkey'. These findings contribute to the commercial propagation and production of the fig crop.

Using modified Fenn diagrams to assess ventilatory acclimatization during ascent to high altitude: Effect of acetazolamide.

High altitude (HA) ascent imposes systemic hypoxia and associated risk of acute mountain sickness. Acute hypoxia elicits a hypoxic ventilatory response (HVR), which is augmented with chronic HA exposure (i.e., ventilatory acclimatization; VA). However, laboratory-based HVR tests lack portability and feasibility in field studies. As an alternative, we aimed to characterize area under the curve (AUC) calculations on Fenn diagrams, modified by plotting portable measurements of end-tidal carbon dioxide ( P ETC O 2 ${P_{{\mathrm{ETC}}{{\mathrm{O}}_{\mathrm{2}}}}}$ ) against peripheral oxygen saturation ( S p O 2 ${S_{{\mathrm{p}}{{\mathrm{O}}_{\mathrm{2}}}}}$ ) to characterize and quantify VA during incremental ascent to HA (n = 46). Secondarily, these participants were compared with a separate group following the identical ascent profile whilst self-administering a prophylactic oral dose of acetazolamide (Az; 125 mg BID; n = 20) during ascent. First, morning P ETC O 2 ${P_{{\mathrm{ETC}}{{\mathrm{O}}_{\mathrm{2}}}}}$ and S p O 2 ${S_{{\mathrm{p}}{{\mathrm{O}}_{\mathrm{2}}}}}$ measurements were collected on 46 acetazolamide-free (NAz) lowland participants during an incremental ascent over 10 days to 5160 m in the Nepal Himalaya. AUC was calculated from individually constructed Fenn diagrams, with a trichotomized split on ranked values characterizing the smallest, medium, and largest magnitudes of AUC, representing high (n = 15), moderate (n = 16), and low (n = 15) degrees of acclimatization. After characterizing the range of response magnitudes, we further demonstrated that AUC magnitudes were significantly smaller in the Az group compared to the NAz group (P = 0.0021), suggesting improved VA. These results suggest that calculating AUC on modified Fenn diagrams has utility in assessing VA in large groups of trekkers during incremental ascent to HA, due to the associated portability and congruency with known physiology, although this novel analytical method requires further validation in controlled experiments. HIGHLIGHTS: What is the central question of this study? What are the characteristics of a novel methodological approach to assess ventilatory acclimatization (VA) with incremental ascent to high altitude (HA)? What is the main finding and its importance? Area under the curve (AUC) magnitudes calculated from modified Fenn diagrams were significantly smaller in trekkers taking an oral prophylactic dose of acetazolamide compared to an acetazolamide-free group, suggesting improved VA. During incremental HA ascent, quantifying AUC using modified Fenn diagrams is feasible to assess VA in large groups of trekkers with ascent, although this novel analytical method requires further validation in controlled experiments.

Effect of Cold Adaptation on the State of Cardiovascular System and Cardiac Tolerance to Ischemia/Reperfusion Injury.

Despite the unconditional success achieved in the treatment and prevention of AMI over the past 40 years, mortality in this disease remains high. Hence, it is necessary to develop novel drugs with mechanism of action different from those currently used in clinical practices. Studying the molecular mechanisms involved in the cardioprotective effect of adapting to cold could contribute to the development of drugs that increase cardiac tolerance to the impact of ischemia/reperfusion. An analysis of the published data shows that the long-term human stay in the Far North contributes to the occurrence of cardiovascular diseases. At the same time, chronic and continuous exposure to cold increases tolerance of the rat heart to ischemia/ reperfusion. It has been demonstrated that the cardioprotective effect of cold adaptation depends on the activation of ROS production, stimulation of the ß2-adrenergic receptor and protein kinase C, MPT pore closing, and KATP channel.