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75 records – page 1 of 8.

Acclimation of a non-indigenous sub-Arctic population: seasonal variation in thyroid function in interior Alaska.

https://arctichealth.org/en/permalink/ahliterature214965
Source
Comp Biochem Physiol A Physiol. 1995 Jun;111(2):209-14
Publication Type
Article
Date
Jun-1995
Author
M. Levine
L. Duffy
D C Moore
L A Matej
Author Affiliation
Department of Psychiatry, Brooke Army Medical Center, Fort Sam Houston, TX 78234, USA.
Source
Comp Biochem Physiol A Physiol. 1995 Jun;111(2):209-14
Date
Jun-1995
Language
English
Publication Type
Article
Keywords
Acclimatization - physiology
Adolescent
Adult
Alaska - ethnology
Arctic regions - ethnology
Body Weight
Humans
Male
Military Personnel
Pineal Gland - physiology
Seasons
Thyroid Gland - physiology
Thyroxine - blood
Triiodothyronine - blood
Weight Gain
Abstract
Total, as well as free, T4 and T3 levels were obtained over four seasons for young male infantry soldiers assigned to interior Alaska. Significant seasonal variations were found in both T3 and T4. Total T4 and T3 levels were highest in winter, while free T4 and T3 levels were highest in early spring. Correlations with melatonin levels from a concurrent study showed an association between late day (17.00) mean spot melatonin levels during the preceding summer and T3 levels in winter and spring. Differences in seasonal T4 and T3 levels between indigenous and newly arrived people in the sub-Arctic may be related not only to cold acclimation but also to light.
PubMed ID
7788348 View in PubMed
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Activation of flavonoid biosynthesis by solar radiation in bilberry ( Vaccinium myrtillus L) leaves.

https://arctichealth.org/en/permalink/ahliterature9570
Source
Planta. 2004 Mar;218(5):721-8
Publication Type
Article
Date
Mar-2004
Author
Laura Jaakola
Kaisu Määttä-Riihinen
Sirpa Kärenlampi
Anja Hohtola
Author Affiliation
Department of Biology/Botany, University of Oulu, POB 3000, 90014, Oulu, Finland. laura.jaakola@oulu.fi
Source
Planta. 2004 Mar;218(5):721-8
Date
Mar-2004
Language
English
Publication Type
Article
Keywords
Acclimatization - physiology - radiation effects
Acyltransferases - genetics - metabolism
Alcohol Oxidoreductases - genetics - metabolism
Flavonoids - biosynthesis - radiation effects
Fruit - metabolism - radiation effects
Gene Expression Regulation, Enzymologic - radiation effects
Gene Expression Regulation, Plant - radiation effects
Mixed Function Oxygenases - genetics - metabolism
Oxygenases - genetics - metabolism
Phenylalanine Ammonia-Lyase - genetics - metabolism
Plant Leaves - metabolism - radiation effects
Research Support, Non-U.S. Gov't
Sunlight
Vaccinium myrtillus - genetics - metabolism - radiation effects
Abstract
The effect of solar radiation on flavonoid biosynthesis was studied in bilberry ( Vaccinium myrtillus L.) leaves. Expression of flavonoid pathway genes of bilberry was studied in the upper leaves of bilberry, exposed to direct sunlight, in the shaded leaves growing lower in the same plants and in fruits. Bilberry-specific digoxigenin-dUTP-labeled cDNA fragments of five genes from the general phenylpropanoid pathway coding phenylalanine ammonia-lyase and from the flavonoid pathway coding chalcone synthase, flavanone 3-hydroxylase, dihydroflavonol 4-reductase, and anthocyanidin synthase were used as probes in gene expression analysis. Anthocyanins, catechins, proanthocyanidins, flavonols and hydroxycinnamic acids from the leaves and fruits were identified and quantified using high-performance liquid chromatography combined with a diode array detector. An increase in the expression of the studied flavonoid pathway genes was observed in leaves growing under direct sun exposure. Also, the concentrations of anthocyanins, catechins, flavonols and hydroxycinnamic acids were higher in the leaves exposed to direct sunlight. However, the concentration of polymeric procyanidins was lower in sun-exposed leaves, whereas that of prodelphinidins was slightly increased. The results give further support for the protective role of flavonoids and hydroxy cinnamic acids against high solar radiation in plants. Also, the roles of different flavonoid compounds as a defense against stress caused by sun exposure is discussed.
PubMed ID
14666422 View in PubMed
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Adaptive Changes in Basal Metabolic Rate in Humans in Different Eco-Geographical Areas.

https://arctichealth.org/en/permalink/ahliterature271453
Source
Coll Antropol. 2015 Dec;39(4):887-92
Publication Type
Article
Date
Dec-2015
Author
Arkady L Maximov
Victor Sh Belkin
Leonid Kalichman
Eugene D Kobyliansky
Source
Coll Antropol. 2015 Dec;39(4):887-92
Date
Dec-2015
Language
English
Publication Type
Article
Keywords
Acclimatization - physiology
Animals
Basal Metabolism - physiology
Egypt
Environment
Female
Humans
Male
Middle Aged
Military Personnel
Abstract
Our aim was to establish whether the human basal metabolic rate (BMR) shifts towards the reduction of vital functions as an adaptation response to extreme environmental conditions. Data was collected in arid and Extreme North zones. The arid zone samples included Bedouins living in the Sinai Peninsula in Egypt, Turkmen students, the Pedagogical University of Chardzhou, Turkmenistan born Russians and Russian soldiers. Soldiers were divided into 3 groups according to the length of their tour of duty in the area: 1st group: up to six months, 2nd group: up to 2 years and the 3rd group: 3-5 years. The Extreme North samples comprised Chukchi natives, 1st generation Russian immigrants born in the area and 3 groups of soldiers comparable to the soldiers from Turkmenistan. BMR values of the new recruits had the highest values of total and relative BMR (1769 ± 16 and 28.3 ± 0.6, correspondingly). The total and relative BMR tended to decrease within a longer adaptation period. The BMR values of officers who served >3 years in Turkmenistan were very similar to the Turkmenistan born Russians (1730 ± 14 vs. 1726 ± 18 and 26.5 ± 0.6 vs. 27.3 ± 0.7, correspondingly). Similarly, in Chukotka, the highest relative BMR was found in the new recruits, serving up to 6 months (28.1 ± 0.7) and was significantly (p 3 years, compared to the middle-aged Chukchi or Chukotka-born Russians (25.8 ± 0.5 vs. 25.6 ± 0.5 and 25.5 ± 0.6, correspondingly). The BMR parameters demonstrated a stronger association with body weight than with age. In extreme environmental conditions, migrant populations showed a decrease in BMR, thus reducing its vital functions. The BMR reduction effect with the adequate adaptive transformation is likely to be the key strategy for developing programs to facilitate human and animal adaptation to extreme factors. This process is aimed at preserving the optimum energy balance and homeostasis while minimizing stress on the body's vital functions.
PubMed ID
26987156 View in PubMed
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Adaptive dimensions of health research among indigenous Siberians.

https://arctichealth.org/en/permalink/ahliterature78876
Source
Am J Hum Biol. 2007 Mar-Apr;19(2):165-80
Publication Type
Article
Author
Snodgrass J Josh
Sorensen Mark V
Tarskaia Larissa A
Leonard William R
Author Affiliation
Department of Anthropology, University of Oregon, Eugene, Oregon 97403, USA. jjosh@uoregon.edu
Source
Am J Hum Biol. 2007 Mar-Apr;19(2):165-80
Language
English
Publication Type
Article
Keywords
Acclimatization - physiology
Arctic Regions
Basal Metabolism
Biomedical research
Cold - adverse effects
Cold Climate - adverse effects
Culture
Geography
Humans
Life Style
Population Groups
Siberia
Time Factors
Abstract
Present evidence suggests that modern humans were the first hominid species to successfully colonize high-latitude environments (> or =55 degrees N). Given evidence for a recent (
PubMed ID
17286259 View in PubMed
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The Arctic Aeromedical Laboratory's thyroid function study : a radiological risk and ethical analysis

https://arctichealth.org/en/permalink/ahliterature292938
Source
National Research Council (US) Committee on Evaluation of 1950s Air Force Human Health Testing in Alaska Using Radioactive Iodine-131. Source Washington (DC): National Academies Press (US); 1996.
Publication Type
Report
Date
1996
Author
National Research Council (U.S.). Committee on Evaluation of 1950s Air Force Human Health Testing in Alaska Using Radioactive Iodine 131
Source
National Research Council (US) Committee on Evaluation of 1950s Air Force Human Health Testing in Alaska Using Radioactive Iodine-131. Source Washington (DC): National Academies Press (US); 1996.
Date
1996
Language
English
Geographic Location
U.S.
Publication Type
Report
Physical Holding
University of Alaska Anchorage
Keywords
Iodine -- Isotopes
Medical ethics -- Alaska
Human Experimentation -- Alaska
Thyroid Gland -- physiology -- Alaska
Thyroid Gland -- radiation effects -- Alaska
Acclimatization -- physiology -- Alaska
Ethics, Medical -- Alaska
Iodine Isotopes -- Alaska
Abstract
During the 1950s, with the Cold War looming, military planners sought to know more about how to keep fighting forces fit and capable in the harsh Alaskan environment. In 1956 and 1957, the U.S. Air Force's former Arctic Aeromedical Laboratory conducted a study of the role of the thyroid in human acclimatization to cold. To measure thyroid function under various conditions, the researchers administered a radioactive medical trace, Iodine-131, to Alaska Natives and white military personnel; based on the study results, the researchers determined that the thyroid did not play a significant role in human acclimatization to cold. When this study of thyroid function was revisited at a 1993 conference on the Cold War legacy in the Arctic, serious questions were raised about the appropriateness of the activity--whether it posed risks to the people involved and whether the research had been conducted within the bounds of accepted guidelines for research using human participants. In particular, there was concern over the relatively large proportion of Alaska Natives used as subjects and whether they understood the nature of the study. This book evaluates the research in detail, looking at both the possible health effects of Iodine-131 administration in humans and the ethics of human subjects research. This book presents conclusions and recommendations and is a significant addition to the nation's current reevaluation of human radiation experiments conducted during the Cold War.
Notes
RC 655.5.A73 1996
Free online version at the National Academies Press at NAP.edu
PubMed ID
25121210 View in PubMed
Less detail

Are the Antarctic dipteran, Eretmoptera murphyi, and Arctic collembolan, Megaphorura arctica, vulnerable to rising temperatures?

https://arctichealth.org/en/permalink/ahliterature261607
Source
Bull Entomol Res. 2014 Aug;104(4):494-503
Publication Type
Article
Date
Aug-2014
Author
M J Everatt
P. Convey
M R Worland
J S Bale
S A L Hayward
Source
Bull Entomol Res. 2014 Aug;104(4):494-503
Date
Aug-2014
Language
English
Publication Type
Article
Keywords
Acclimatization - physiology
Adaptation, Biological - physiology
Analysis of Variance
Animals
Antarctic Regions
Arctic Regions
Climate change
Ecosystem
Insects - physiology
Motor Activity - physiology
Statistics, nonparametric
Temperature
Abstract
Polar terrestrial invertebrates are suggested as being vulnerable to temperature change relative to lower latitude species, and hence possibly also to climate warming. Previous studies have shown Antarctic and Arctic Collembola and Acari to possess good heat tolerance and survive temperature exposures above 30 °C. To test this feature further, the heat tolerance and physiological plasticity of heat stress were explored in the Arctic collembolan, Megaphorura arctica, from Svalbard and the Antarctic midge, Eretmoptera murphyi, from Signy Island. The data obtained demonstrate considerable heat tolerance in both species, with upper lethal temperatures =35 °C (1 h exposures), and tolerance of exposure to 10 and 15 °C exceeding 56 days. This tolerance is far beyond that required in their current environment. Average microhabitat temperatures in August 2011 ranged between 5.1 and 8.1 °C, and rarely rose above 10 °C, in Ny-Ålesund, Svalbard. Summer soil microhabitat temperatures on Signy Island have previously been shown to range between 0 and 10 °C. There was also evidence to suggest that E. murphyi can recover from high-temperature exposure and that M. arctica is capable of rapid heat hardening. M. arctica and E. murphyi therefore have the physiological capacity to tolerate current environmental conditions, as well as future warming. If the features they express are characteristically more general, such polar terrestrial invertebrates will likely fare well under climate warming scenarios.
PubMed ID
24816280 View in PubMed
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[Assessment of the significance of climatogeographic conditions as health risk factors].

https://arctichealth.org/en/permalink/ahliterature143397
Source
Gig Sanit. 2010 Mar-Apr;(2):44-6
Publication Type
Article
Author
R S Rakhmanov
D A Gadzhiibragimov
M A Medzhikova
O A Kudriavtseva
Source
Gig Sanit. 2010 Mar-Apr;(2):44-6
Language
Russian
Publication Type
Article
Keywords
Acclimatization - physiology
Adolescent
Adult
Climate
Environmental Exposure
Environmental Illness - epidemiology
Health Status Indicators
Humans
Incidence
Male
Middle Aged
Risk Assessment - methods
Risk factors
Russia - epidemiology
Young Adult
Abstract
Under the conditions of hot and mountain-continental climate, the morbidity rates in the inhabitants were estimated to be significantly lower than those in young men who had not been acclimatized or adapted to living conditions and in non-acclimatized men. A role of individual physical environmental factors (temperature, relative humidity, barometric pressure, average and maximum air speed) and integral exposure by the wind chill index (a combined impact of an air speed and ambient temperature) as risk factors to human health was defined, The mountain-continental climate showed a relationship of the influence of these factors to habitation at different altitudes above sea level.
PubMed ID
20491267 View in PubMed
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Basal metabolic rate in the Yakut (Sakha) of Siberia.

https://arctichealth.org/en/permalink/ahliterature6646
Source
Am J Hum Biol. 2005 Mar-Apr;17(2):155-72
Publication Type
Article
Author
J Josh Snodgrass
William R Leonard
Larissa A Tarskaia
Vasili P Alekseev
Vadim G Krivoshapkin
Author Affiliation
Department of Anthropology, Northwestern University, Evanston, Illinois 60208, USA. j-snodgrass@northwestern.edu
Source
Am J Hum Biol. 2005 Mar-Apr;17(2):155-72
Language
English
Publication Type
Article
Keywords
Acclimatization - physiology
Adolescent
Adult
Age Distribution
Basal Metabolism - physiology
Cold Climate
Comparative Study
Female
Humans
Inuits
Life Style - ethnology
Male
Middle Aged
Regression Analysis
Research Support, Non-U.S. Gov't
Sex Distribution
Siberia - ethnology
Abstract
Human indigenous circumpolar populations have elevated basal metabolic rates (BMRs) relative to predicted values; this metabolic elevation has been postulated to be a physiological adaptation to chronic and severe cold stress. The present study examines BMR in the Yakut, an indigenous high-latitude population from the Sakha Republic of Russia to determine (1) whether the Yakut show evidence of an elevated BMR, (2) if the Yakut display evidence of age-related changes in BMR, and (3) whether lifestyle differences influence BMR. BMR was measured during the late summer in 75 women and 50 men (ages 18-56 years) from the Siberian village of Berdygestiakh. Measured BMR (+/- SEM) of the entire sample was significantly elevated (+6.5%) compared to predictions based on body mass (6,623.7 +/- 94.9 vs. 6,218.2 +/- 84.7 kJ/day; P
PubMed ID
15736182 View in PubMed
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Changes in aggressive behavior, thermoregulation, and endocrine responses in BALB/cLac and C57Bl/6J mice under cold exposure.

https://arctichealth.org/en/permalink/ahliterature11761
Source
Physiol Behav. 1993 Mar;53(3):535-8
Publication Type
Article
Date
Mar-1993
Author
M P Moshkin
M A Potapov
O F Frolova
V I Evsikov
Author Affiliation
Biological Institute, Siberian Branch of Russia's Academy of Sciences, Novosibirsk.
Source
Physiol Behav. 1993 Mar;53(3):535-8
Date
Mar-1993
Language
English
Publication Type
Article
Keywords
11-Hydroxycorticosteroids - blood
Acclimatization - physiology
Aggression - physiology
Agonistic Behavior - physiology
Animals
Body Temperature Regulation - physiology
Comparative Study
Energy Metabolism - physiology
Glucocorticoids - blood
Male
Mice
Mice, Inbred BALB C
Mice, Inbred C57BL
Norepinephrine - physiology
Species Specificity
Testosterone - blood
Abstract
Effect of cold exposure on aggressive behavior, on the concentrations of testosterone and glucocorticoids, as well as on the oxygen consumption at different ambient temperatures, and calorigenic effect of noradrenaline have been studied in BALB/cLac and C57Bl/6J males. Under normal temperature conditions, there have been no significant interstrain differences. After cold exposure (5 weeks at 6-8 degrees C), C57Bl/6J mice exhibited more pronounced adaptive changes in thermoregulation and endocrine status (increase of glucocorticoids and decrease of testosterone concentrations were less expressed in C57Bl/6J than in BALB/cLac). At the same time, males of this strain demonstrated more intensive aggression than BALB/cLac mice. Some relations between physiological and behavioral changes caused by cold exposure are discussed.
PubMed ID
8451320 View in PubMed
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Changes in cold tolerance due to a 14-day stay in the Canadian Arctic.

https://arctichealth.org/en/permalink/ahliterature210669
Source
Int J Biometeorol. 1996 Nov;39(4):182-6
Publication Type
Article
Date
Nov-1996
Author
S D Livingstone
T. Romet
A A Keefe
R W Nolan
Author Affiliation
Defence and Civil Institute of Environmental Medicine, North York, Ontario, Canada.
Source
Int J Biometeorol. 1996 Nov;39(4):182-6
Date
Nov-1996
Language
English
Publication Type
Article
Keywords
Acclimatization - physiology
Adult
Arctic Regions
Body Temperature Regulation - physiology
Canada
Case-Control Studies
Cold Climate
Humans
Male
Time Factors
Abstract
Response to cold exposure tests both locally and of the whole body were examined in subjects who stayed in the arctic (average maximum and minimum temperatures -11 and -21 degrees C respectively) for 14 days of skiing and sleeping in tents. These changes were compared to responses in subjects living working in Ottawa, Canada (average max. and min. temperatures -5 and -11 degrees C respectively). The tests were done before the stay in the Arctic (Pre), immediately after the return (Post 1) and approximately 32 days after the return (Post 2). For the whole-body cold exposure each subject, wearing only shorts and lying on a rope mesh cot, was exposed to an ambient temperature of 10 degrees C. There was no consistent response in the changes of metabolic or body temperature to this exposure in either of groups and, in addition, the changes over time were variable. Cold induced vasodilatation (CIVD) was determined by measuring temperature changes in the middle finger of the nondominant hand upon immersion in ice water for 30 min. CIVD was depressed after the Arctic exposure whilst during the Post 2 testing, although variable, did not return to the Pre values; the responses of the control group were similar. These results indicate that normal seasonal changes may be as important in adaptation as a stay in the Arctic. Caution is advised in the separation of seasonal effects when examining the changes in adaptation after exposure to a cold environment.
PubMed ID
9008430 View in PubMed
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75 records – page 1 of 8.