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Genes Feb 2019Whether Andean populations are genetically adapted to high altitudes has long been of interest. Initial studies focused on physiological changes in the O₂ transport... (Review)
Review
Whether Andean populations are genetically adapted to high altitudes has long been of interest. Initial studies focused on physiological changes in the O₂ transport system that occur with acclimatization in newcomers and their comparison with those of long-resident Andeans. These as well as more recent studies indicate that Andeans have somewhat larger lung volumes, narrower alveolar to arterial O₂ gradients, slightly less hypoxic pulmonary vasoconstrictor response, greater uterine artery blood flow during pregnancy, and increased cardiac O utilization, which overall suggests greater efficiency of O₂ transfer and utilization. More recent single nucleotide polymorphism and whole-genome sequencing studies indicate that multiple gene regions have undergone recent positive selection in Andeans. These include genes involved in the regulation of vascular control, metabolic hemostasis, and erythropoiesis. However, fundamental questions remain regarding the functional links between these adaptive genomic signals and the unique physiological attributes of highland Andeans. Well-designed physiological and genome association studies are needed to address such questions. It will be especially important to incorporate the role of epigenetic processes (i.e.; non-sequence-based features of the genome) that are vital for transcriptional responses to hypoxia and are potentially heritable across generations. In short, further exploration of the interaction among genetic, epigenetic, and environmental factors in shaping patterns of adaptation to high altitude promises to improve the understanding of the mechanisms underlying human adaptive potential and clarify its implications for human health.
Topics: Acclimatization; Adaptation, Physiological; Altitude; Humans; Hypoxia; Oxygen; Polymorphism, Single Nucleotide; Selection, Genetic
PubMed: 30781443
DOI: 10.3390/genes10020150 -
Physical Biology Jun 2021A common signature of cell adaptation to stress is the improved resistance upon priming by prior stress exposure. In the context of hyperthermia, priming or...
A common signature of cell adaptation to stress is the improved resistance upon priming by prior stress exposure. In the context of hyperthermia, priming or preconditioning with sublethal heat shock can be a useful tool to confer thermotolerance and competitive advantage to cells. In the present study, we develop a data-driven modeling framework that is simple and generic enough to capture a broad set of adaptation behaviors to heat stress at both molecular and cellular levels. The model recovers the main features of thermotolerance and clarifies the tradeoff principles which maximize the thermotolerance effect. It therefore provides an effective predictive tool to design preconditioning and fractionation hyperthermia protocols for therapeutic purpose.
Topics: Cell Physiological Phenomena; Heat-Shock Response; Models, Biological; Thermotolerance
PubMed: 34156353
DOI: 10.1088/1478-3975/ac02a8 -
International Journal of Environmental... Nov 2018Madagascar is cited as one of the most vulnerable countries to the effects of climate change, with significant impacts to the health of its population. In this study,... (Review)
Review
Madagascar is cited as one of the most vulnerable countries to the effects of climate change, with significant impacts to the health of its population. In this study, the vulnerability of Madagascar's health sector to climate change was assessed and appropriate adaptation measures were identified. In order to assess climate risks, vulnerability and identify adaptation options, the Madagascar Ministry of Public Health as well as the National Meteorological and Hydrological Service worked in close collaboration with a team of local experts to conduct a literature review, field surveys, and analyses of current and future climate and health trends. Four climate-sensitive diseases of primary concern are described in the study: acute respiratory infections (ARI), diarrhea, malnutrition, and malaria. Baseline conditions of these four diseases from 2000 to 2014 show acute respiratory infections and diarrheal diseases are increasing in incidence; while incidence of malnutrition and malaria decreased over this period. To assess future impacts in Madagascar, this baseline information was used with climate projections for the two scenarios-RCP 4.5 and RCP 8.5-for the periods 2016⁻2035, 2036⁻2070 and 2071⁻2100. Future climate conditions are shown to exacerbate and increase the incidence of all four climate sensitive diseases. Further analysis of the exposure, sensitivity and adaptive capacity to the climate hazards suggests that the health sector in four regions of Madagascar is particularly vulnerable. The study recommends adaptation measures to improve the monitoring and early warning systems for climate sensitive diseases, as well as to reduce population vulnerability.
Topics: Acclimatization; Adaptation, Physiological; Climate Change; Diarrhea; Environmental Monitoring; Health Status Indicators; Humans; Incidence; Madagascar; Malaria; Malnutrition; Population Surveillance; Public Health Surveillance; Respiratory Tract Infections
PubMed: 30486244
DOI: 10.3390/ijerph15122643 -
Global Change Biology May 2021Marine microalgae are a diverse group of microscopic eukaryotic and prokaryotic organisms capable of photosynthesis. They are important primary producers and carbon... (Review)
Review
Marine microalgae are a diverse group of microscopic eukaryotic and prokaryotic organisms capable of photosynthesis. They are important primary producers and carbon sinks but their physiology and persistence are severely affected by global climate change. Powerful experimental evolution technologies are being used to examine the potential of microalgae to respond adaptively to current and predicted future conditions, as well as to develop resources to facilitate species conservation and restoration of ecosystem functions. This review synthesizes findings and insights from experimental evolution studies of marine microalgae in response to elevated temperature and/or pCO . Adaptation to these environmental conditions has been observed in many studies of marine dinoflagellates, diatoms and coccolithophores. An enhancement in traits such as growth and photo-physiological performance and an increase in upper thermal limit have been shown to be possible, although the extent and rate of change differ between microalgal taxa. Studies employing multiple monoclonal replicates showed variation in responses among replicates and revealed the stochasticity of mutations. The work to date is already providing valuable information on species' climate sensitivity or resilience to managers and policymakers but extrapolating these insights to ecosystem- and community-level impacts continues to be a challenge. We recommend future work should include in situ experiments, diurnal and seasonal fluctuations, multiple drivers and multiple starting genotypes. Fitness trade-offs, stable versus plastic responses and the genetic bases of the changes also need investigating, and the incorporation of genome resequencing into experimental designs will be invaluable.
Topics: Acclimatization; Climate Change; Ecosystem; Microalgae; Oceans and Seas
PubMed: 33547698
DOI: 10.1111/gcb.15546 -
International Journal of Molecular... May 2020Iron (Fe) is essential for life because of its role in protein cofactors. Photosynthesis, in particular photosynthetic electron transport, has a very high demand for Fe... (Review)
Review
Iron (Fe) is essential for life because of its role in protein cofactors. Photosynthesis, in particular photosynthetic electron transport, has a very high demand for Fe cofactors. Fe is commonly limiting in the environment, and therefore photosynthetic organisms must acclimate to Fe availability and avoid stress associated with Fe deficiency. In plants, adjustment of metabolism, of Fe utilization, and gene expression, is especially important in the chloroplasts during Fe limitation. In this review, we discuss Fe use, Fe transport, and mechanisms of acclimation to Fe limitation in photosynthetic lineages with a focus on the photosynthetic electron transport chain. We compare Fe homeostasis in Cyanobacteria, the evolutionary ancestors of chloroplasts, with Fe homeostasis in green algae and in land plants in order to provide a deeper understanding of how chloroplasts and photosynthesis may cope with Fe limitation.
Topics: Acclimatization; Biological Evolution; Chlorophyta; Chloroplasts; Cyanobacteria; Electron Transport; Homeostasis; Iron; Photosynthesis; Plants
PubMed: 32403383
DOI: 10.3390/ijms21093395 -
Deutsches Arzteblatt International Sep 2017The randomized, controlled trial (RCT) is the gold standard of scientific evidence for the attribution of clinical effects (benefits and harms) to medical interventions.... (Review)
Review
BACKGROUND
The randomized, controlled trial (RCT) is the gold standard of scientific evidence for the attribution of clinical effects (benefits and harms) to medical interventions. Many different designs for RCTs have been developed in order to counter legitimate critical objections and to better adapt the trials to the continually changing challenges that face clinical research.
METHODS
The diversity and adaptability of randomized trial designs are presented and discussed on the basis of a selective literature review and specific illustrative examples.
RESULTS
A wide range of RCT designs enables adaptation to special research tasks and clinical framework conditions. These include (among others) crossover trials, n=1 trials, factorial RCT designs, and cluster-randomized trials. In addition, adaptive designs such as modern platform trials and pragmatic RCTs with simplified clinical questions and less severely restricted patient groups make broad recruitment of patients possible even in routine clinical practice.
CONCLUSION
Only the randomized allocation of subjects to the treatment and control groups, which is the defining property of RCTs, can adequately ensure that traits of the subjects which might disturb or bias a comparison of two or more medical interventions, will be evenly distributed across groups, regardless of whether these traits are known or unknown. The methodological variants and further elaborations of the RCT that are discussed here will help protect patients by enabling the assessment of the benefits and harms of medical methods and products on the basis of robust evidence even in the present era of rapid innovation.
Topics: Cross-Over Studies; Randomized Controlled Trials as Topic; Research Design
PubMed: 29017690
DOI: 10.3238/arztebl.2017.0635 -
Frontiers in Public Health 2022Implementation strategies supporting the translation of evidence into practice need to be tailored and adapted for maximum effectiveness, yet the field of adapting...
INTRODUCTION
Implementation strategies supporting the translation of evidence into practice need to be tailored and adapted for maximum effectiveness, yet the field of adapting implementation strategies remains nascent. We aimed to adapt "Getting To Outcomes" (GTO), a 10-step implementation playbook designed to help community-based organizations plan and evaluate behavioral health programs, into "Getting To Implementation" (GTI) to support the selection, tailoring, and use of implementation strategies in health care settings.
METHODS
Our embedded evaluation team partnered with operations, external facilitators, and site implementers to employ participatory methods to co-design and adapt GTO for Veterans Health Administration (VA) outpatient cirrhosis care improvement. The Framework for Reporting Adaptations and Modifications to Evidenced-based Implementation Strategies (FRAME-IS) guided documentation and analysis of changes made pre- and post-implementation of GTI at 12 VA medical centers. Data from multiple sources (interviews, observation, content analysis, and fidelity tracking) were triangulated and analyzed using rapid techniques over a 3-year period.
RESULTS
Adaptations during pre-implementation were planned, proactive, and focused on context and content to improve acceptability, appropriateness, and feasibility of the GTI playbook. Modifications during and after implementation were unplanned and reactive, concentrating on adoption, fidelity, and sustainability. All changes were collaboratively developed, fidelity consistent at the level of the facilitator and/or implementer.
CONCLUSION
GTO was initially adapted to GTI to support health care teams' selection and use of implementation strategies for improving guideline-concordant medical care. GTI required ongoing modification, particularly in steps regarding team building, context assessment, strategy selection, and sustainability due to difficulties with step clarity and progression. This work also highlights the challenges in pragmatic approaches to collecting and synthesizing implementation, fidelity, and adaptation data.
TRIAL REGISTRATION
This study was registered on ClinicalTrials.gov (Identifier: NCT04178096).
Topics: Humans; Ambulatory Care; Patient Care Team; Psychiatry
PubMed: 36684876
DOI: 10.3389/fpubh.2022.980958 -
International Journal of Molecular... Jan 2022Due to the economic and ecological importance of forest trees, modern breeding and genetic manipulation of forest trees have become increasingly prevalent. The... (Review)
Review
Due to the economic and ecological importance of forest trees, modern breeding and genetic manipulation of forest trees have become increasingly prevalent. The CRISPR-based technology provides a versatile, powerful, and widely accepted tool for analyzing gene function and precise genetic modification in virtually any species but remains largely unexplored in forest species. Rapidly accumulating genetic and genomic resources for forest trees enabled the identification of numerous genes and biological processes that are associated with important traits such as wood quality, drought, or pest resistance, facilitating the selection of suitable gene editing targets. Here, we introduce and discuss the latest progress, opportunities, and challenges of genome sequencing and editing for improving forest sustainability.
Topics: Acclimatization; CRISPR-Cas Systems; Forests; Gene Editing; Genome, Plant; Plant Breeding; Trees; Whole Genome Sequencing
PubMed: 35055150
DOI: 10.3390/ijms23020966 -
Ear and Hearing 2021Audiologists and hearing aid users (HAUs) generally agree that an adaptation period is needed following the first hearing aid (HA) experience. The main purpose of this... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVES
Audiologists and hearing aid users (HAUs) generally agree that an adaptation period is needed following the first hearing aid (HA) experience. The main purpose of this study is to investigate the acclimatization of older adult listeners with hearing loss to HAs using listening effort and behavioral measures.
DESIGN
Participants (N=47) were older adults with mild to moderately severe sensorineural hearing loss. Thirty-two participants were new HAUs and 15 participants were experienced HAUs. New HAUs were randomly assigned to one of two groups: noise reduction algorithms and directional microphones activated or noise reduction algorithms and directional microphones deactivated. Speech recognition in noise and listening effort were assessed on 8 different occasions during a 10-month period. A dual-task paradigm was used to measure the listening effort deployed to recognize speech in noise. The primary task consisted of the Hearing in Noise Test which also served as the behavioral speech in noise measure. The secondary task was a tactile pattern-recognition task in which participants had to identify a sequence of three tactile stimuli that varied in duration. The two listening effort outcomes were the proportional dual-task cost and the response time on the secondary task. Cognitive abilities, including working memory and speed of processing, were evaluated using the Reading Span Test and the Digit Symbol Substitution Test, respectively.
RESULTS
Results show a significant time*group interaction. Both groups of new HAUs showed improvement over time in speech in noise performances (change of ~2 dB signal to noise ratio) and the experienced HAUs did not improve over time. The acclimatization effect was observed over a period of 4 weeks. There was no significant change over time on both measures of listening effort. There was no association between amplitude of acclimatization and the cognitive abilities measured.
CONCLUSION
An acclimatization effect following HA experience was observed. Specifically, the new HAUs displayed a clinically significant change of 2 dB in signal to noise ratio on the Hearing in Noise Test 4 weeks following their initial fitting. The acclimatization effect is not correlated to cognitive abilities.
Topics: Acclimatization; Aged; Hearing Aids; Hearing Loss, Sensorineural; Humans; Noise; Speech Perception
PubMed: 32769437
DOI: 10.1097/AUD.0000000000000913 -
Current Opinion in Plant Biology Aug 2020In the context of the global challenge of climate change, mitigation strategies are needed to adapt crops to novel environments. The main goal to address this is an... (Review)
Review
In the context of the global challenge of climate change, mitigation strategies are needed to adapt crops to novel environments. The main goal to address this is an understanding of the genetic basis of crop adaptation to different agro-ecological conditions. The movement of crops during the Colombian Exchange that started with the travels of Columbus in 1492 is an example of rapid adaptation to novel environments. Many diversification-related traits have been characterised in multiple crop species, and association-mapping analyses have identified loci involved in these. Here, we present an overview of current knowledge regarding the molecular basis related to the complex patterns of crop adaptation and dissemination, particularly outside their centres of origin. Investigation of the genomic basis of crop expansion offers a powerful contribution to the development of tools to identify and exploit valuable genetic diversity and to improve and design novel resilient crop varieties.
Topics: Acclimatization; Adaptation, Physiological; Climate Change; Crops, Agricultural; Phenotype
PubMed: 32057695
DOI: 10.1016/j.pbi.2019.12.011