Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Cold Climate”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources
PubMed1990

The effect of climate on fractures and deaths due to falls among white women.

Climatic conditions may affect the incidence of fractures and fall deaths. Analysis of national fatality data shows that among white women, those living in colder climates have higher rates of fall deaths. Fall deaths increase in winter in all regions, but especially so in colder states. In a prospective cohort study of 96,506 predominantly white female nurses 35-59 years of age, we found that, after controlling for personal and lifestyle characteristics, those women residing in colder climate also had a higher incidence of hip and forearm fracture. In colder states, fracture rates were substantially higher in winter than in summer. A cold climate appears to be a significant risk factor for both fractures and fall deaths among white women, particularly as they age.

Accidental Falls↗
PubMed1982

Effect of temperature on spore germination and vegetative cell growth of Clostridium botulinum.

Spore germination and vegetative growth of Clostridium botulinum type E strain VH at 2 to 50 degrees C were studied. At all of these temperatures, germination began immediately after the addition of the spores to the germination medium. Microscopic observations during germination revealed three types of spores: phase bright (ungerminated), phase variable (partially germinated), and phase dark (fully germinated). At all temperatures except 50 degrees C, there was a pronounced lag between the initial appearance of phase-variable spores and their eventual conversion to phase-dark spores. The number of partially germinated spores increased steadily, reaching 40 to 60% by 18 to 21 h of incubation. During this time, phase-dark, fully germinated spores developed slowly and did not exceed 28% in any of the samples. At 18 to 26 h of incubation, the rate of full germination increased abruptly four-fold. There was extensive and relatively rapid germination at 2 degrees C, the lowest temperature tested, yielding about 60% phase-variable spores by 18 h, which became phase-dark by 26 h of incubation. The optimum temperature for partial and full germination was consistently 9 degrees C. Germination at 50 degrees C was exceptionally rapid and was completed within 1 to 2 h, although 40% remained phase bright. Vegetative cells showed detectable growth at 6 to 41 degrees C, with a distinct optimum at 32.5 degrees C. No growth occurred at 50 degrees C, and only marginal growth was observed at 6 to 14 degrees C. The psychrophilic nature of the germination process coupled with the cold tolerance of vegetative growth appears to give C. botulinum type E an advantage in cold climates as well as in cold-stored foods.

Clostridium botulinum↗
PubMed2000

The relationship between mortality caused by cardiovascular diseases and two climatic factors in densely populated areas in Norway and Ireland.

BACKGROUND: Seasonal variations in mortality due to cardiovascular disease have been demonstrated in many countries, with the highest levels occurring during the coldest months of the year. It has been suggested that this can be explained by cold climate. In this study, we examined the relationship between mortality and two different climatic factors in two densely populated areas (Dublin, Ireland and Oslo/Akershus, Norway). METHODS: Meteorological data (mean daily air temperatures and wind speed) and registered daily mortality data for three groups of cardiovascular disease for the period 1985-1994 were obtained for the two respective areas. The daily mortality ratio for both men and women of 60 years and older was calculated from the mortality data. The wind chill temperature equivalent was calculated from the Siple and Passels formula. RESULTS: The seasonal variations in mortality were greater in Dublin than in Oslo/Akershus, with mortality being highest in winter. This pattern was similar to that previously shown for the two respective countries as a whole. There was a negative correlation between mortality and both air temperature and wind chill temperature equivalent for all three groups of diseases. The slopes of the linear regression lines describing the relationship between mortality and air temperature were a lot steeper for the Irish data than for the Norwegian data. However, the difference between the steepness of the linear regression lines for the relationship between mortality and wind chill temperature equivalent was considerably less between the two areas. This can be explained by the fact that Dublin is a much windier area than Oslo/Akershus. CONCLUSION: The results of this study demonstrate that the inclusion of two climatic factors rather than just one changes the impression of the relationship between climate and cardiovascular disease mortality.

Adult↗
PubMed1995

Facial cooling, but not nasal breathing of cold air, induces bronchoconstriction: a study in asthmatic and healthy subjects.

Reflex-mediated bronchoconstriction in cold climates may be more important than it has previously been thought. This issue has seldom been studied using physiological methods. We wanted to investigate, using physiological methods, what triggers the bronchoconstriction occurring at cold ambient temperature during resting nasal ventilation: cooling of the skin of the face or cooling of the nasal cavity. Three experiments were carried out in 15 stable asthmatics and 10 healthy volunteers: 1) a whole-body exposure to subfreezing temperature in an environmental chamber, during which the subjects breathed cold air through the nose; 2) a similar exposure to subfreezing temperature except that the subjects now breathed warm air through the mouth from outside the chamber; and 3) nasal breathing of subfreezing air from a heat exchanger whilst the subjects sat at room temperature. Spirometric values and facial skin temperature were measured both during and after the exposures. Maximal decrements (means +/- standard errors) of forced expiratory volume in one second (FEV1) in experiments 1, 2 and 3 were: 5.8 +/- 0.8, 5.1 +/- 0.7 and 2.1 +/- 0.5%, respectively (p < 0.001). Only the two experiments in the environmental chamber induced significant bronchoconstriction. All responses were of similar magnitude in the asthmatic and the healthy subjects. The cooling of the skin of the face seems to be the trigger for the bronchoconstriction during resting nasal ventilation at cold ambient temperature both in asthmatic and nonasthmatic subjects.

Adult↗
PubMedDate not supplied

Psychological and psychophysiological factors in prevention and treatment of cold injuries.

Cold injured patients in Alaska come from many sources. Although sport and work continues to provide large numbers of cold injured, most severe repeat injuries tend to reflect other biopsychosocial consequences. Certain behaviors can increase the probability of injury, however all persons living in cold climates are potential candidates. One can decrease risk by education, knowledge and intelligent behavior. Proper respect for adequate protection and hydration seem to be critical factors. Understanding the psychological, physiological and psychophysiological aspects of the cold environment performer helps refine the prevention and treatment strategies for cold injury. Skill training with bio-behavioral methods, such as thermal biofeedback, and the value of medical psychotherapy appear to offer continued promise by facilitating physiologic recovery from injury, as well as assisting in long term rehabilitation. Both approaches increase the likelihood of a favorable healing response by soliciting active patient participation. Medical Psychotherapy for traumatic injuries can also help identify and manage cognitive emotional issues for families and patients faced with the permanent consequences of severe thermal injuries. Thermal biofeedback therapy has the potential benefit of encouraging greater self-reliance and responsibility for self-regulating overall health by integrating self-management skills regarding physiology, diet and lifestyle. Inpatient and outpatient biofeedback training offers specific influence over vascular responses for healing, as well as providing an effective tool for pain management. Interest in cold region habitation has continued to expand our study of human tolerance to harsh, extreme environments. Biological, psychological, sociological, and anthropological views on adaptation, habituation, acclimatization, and injury in cold environments acknowledges the role of development, learning and educated responses to cold environments. The study of health, performance, and injury prevention in extreme isolated cold environments has important strategic and scientific implications. What is learned from behavioral studies of cold survival provides an opportunity to increase our scientific knowledge and understanding. These cold research findings can assist in our future exploration of cold, underwater farming at great depths, and to far distance space travel to cold planets. The relatively new research frontier "Polar Psychology" has evolved to study how interactions with cold environments can have both positive and/or negative consequences. This research simulates the psychological factors likely to be encountered while exploring isolated cold regions of distant galaxies. The psychological and psychophysiological correlates of cold experience appear to be a function of four interactive issues: the environment, genetic predisposition, learning or experience, and finally perception or cognition. Individual cold tolerance seems to relate heavily on sensation, perception and behavior.(ABSTRACT TRUNCATED AT 400 WORDS)

Acclimatization↗
PubMed1995

Survival and development of Ixodes scapularis (Acari: Ixodidae) under various climatic conditions in Ontario, Canada.

Distribution of the blacklegged tick, Ixodes scapularis Say, is poorly defined in Ontario. An endemic population is known on Long Point peninsula, Lake Erie, Ontario, but I. scapularis adults have also been collected from other localities within the province. To test the hypothesis that distribution of the blacklegged tick is limited by cold climatic extremes, 35 fed female, 70 unfed adult, and 70 unfed nymphal I. scapularis were held in containers within four natural habitats on Long Point (42 degrees 36' N; 80 degrees 5' W) and at northern localities near Ottawa (45 degrees 27' N; 75 degrees 42' W), Hearst (49 degrees 40' N; 83 degrees 41' W), and Kenora (49 degrees 47' N; 94 degrees 29' W), Ontario, from early December 1991 until May 1993. At the northern localities, 84.8 and 30.5% of fed females and unfed adults survived overwinter, respectively. On Long Point, 56.4% of fed females and 23.6% of unfed adults successfully overwintered. Longevity of fed females and unfed adults was increased by > 2 mo at the northern localities compared with Long Point, although survival rates for unfed nymphs at the northern sites and on Long Point were similar. Females within the four habitats on Long Point, and at Kenora and Ottawa, laid eggs from late April to mid-May, whereas eggs were deposited in late June at Hearst. Emergence of larvae from eggs began in late July or early August on Long Point and at Ottawa. Larvae were first observed in early October at Kenora, and no larvae emerged during 1992 at Hearst. Some eggs that overwintered during 1992-1993 at the northern sites were viable; however, hatching rate was < 10%. The minimum duration of the life cycle of I. scapularis is extended when ticks are introduced into regions of the province with seasonal degree-day accumulations lower than those observed on Long Point. Delays in deposition of eggs and emergence of larvae at Hearst and Kenora were likely a result of insufficient accumulation of degree-days above threshold temperatures for development in 1992. Though some eggs can overwinter successfully, suggesting that latitude-related reduction in seasonal temperature may not limit distribution of this tick in Ontario, hatchability was low. This factor, combined with innate incremental mortality at each instar, difficulty in finding a mate, and low density of medium to large mammal hosts for adults, may mitigate against establishment of I. scapularis by introduction of individual ticks into certain northern regions.

Animals↗
PubMed2003

The Finno-Ugrian suicide hypothesis: variation in European suicide rates by latitude and longitude.

The marked variation regarding the suicide rate in 34 European countries is well described by regressing the national suicide rate on the capital cities' latitudes and on an interaction term of squared latitude multiplied with longitude. The interaction term explains 40.8% and 29.1% of men's and women's suicide rate, respectively, and latitude explains a further significant increment of 10.9% and 10.6% variance of men's and women's suicide rate, respectively. This regression model quantifies the Finno-Ugrian suicide hypothesis of Kondrichin and of Marusic and Farmer. The European countries highest in suicide rate constitute a contiguous, J-shaped belt, spanning from Finland to Austria. This area maps onto the second principal component identified for European gene distribution, representing ancestral adaptation to cold climates and the Uralic language dispersion. Thus, population differences in genetic risk factors may account for the spatial pattern in European suicide rates.

Acclimatization↗
PubMed1977

Loss of body weight and fat during exercise in a cold chamber.

Ten men spent one week in a cold climatic facility performing a simulated arctic military exercise demanding an energy expenditure of 13-16 MJ-day-1. Although the ration pack was adequate, extensive plate wastage led to a negative energy balance of 2.2 MJ-day-1. Fluid intake was also insufficient, with a 3.25% decrease of body weight, and a 9.7% decrease in skin thickness over the cold exposure. Extensive fat mobilization was indicated by a decrease of skinfold thicknesses, an increase of body density, and associated ketonuria and glycosuria. The fat breakdown far exceeded the calculated energy deficit, and it is postulated that much of the "surplus" energy was required for synthesis of additional muscle protein. In the arctic environment, both energy and fluid balances are better maintained because there are few distraction from the simple pleasure of preparing and eating meals.

Adipose Tissue↗
PubMed2002

The costal skeleton of Shanidar 3 and a reappraisal of Neandertal thoracic morphology.

For over a century, Neandertal rib remains have engendered frequent discussions of "barrel-shaped" thoraces, largely in the absence of systematic comparison and hard data. We present here a description of the relatively complete ribcage of the Near Eastern Shanidar 3 Neandertal. We also furnish metric and non-metric comparisons of the Shanidar 3 ribs with other Near Eastern and European Neandertals, the Nariokotome (Homo erectus/ergaster) specimen, Levantine archaic/early modern humans, early and later European modern humans, and a sample of recent Euroamerican males. It is clear from these comparisons that Neandertals share with modern humans the fundamentally human thoracic "bauplan" that first evolved in the early Pleistocene. Yet it is also apparent that the ribcage of Neandertals differ in several anatomical details from those of fully modern humans. Rib curvature, posterior angle, mid-shaft cross-sectional size and shape, and muscle scarring varies considerably among Neandertals and across all samples when considered in isolated ribs. However, normalized metric and discrete patterning across the greater thorax clearly distinguishes Neandertals from our comparative samples. This is most marked in the inferior thorax where Neandertals (and probably earlier Homo) exhibit larger, more rounded and rugose ribs, and a greater costal area (thoracic volume). Greater lower rib cross-sectional robusticity and muscle scarring indicates relatively elevated ventilatory levels. Greater thoracic volume in Neandertals probably reflects greater body mass compared with modern humans since lung volume scales isometrically to body mass among mammals. Neandertal and modern human pulmonary capacity, normalized for body mass differences, was therefore roughly equivalent in the context of detailed differences in thoracic shape. To the extent that cold-climate adaptation is involved, Near Eastern Neandertals appear less "hyper-polar" in thoracic shape than their European counterparts as is also true for several other body proportion measures that are clinally distributed across the known Neandertal range.

Adaptation, Physiological↗
PubMed2005

The sweet thing about Type 1 diabetes: a cryoprotective evolutionary adaptation.

The reasons for the uneven worldwide distribution of Type 1 diabetes mellitus have yet to be fully explained. Epidemiological studies have shown a higher prevalence of Type 1 diabetes in northern Europe, particularly in Scandinavian countries, and Sardinia. Recent animal research has uncovered the importance of the generation of elevated levels of glucose, glycerol and other sugar derivatives as a physiological means for cold adaptation. High concentrations of these substances depress the freezing point of body fluids and prevent the formation of ice crystals in cells through supercooling, thus acting as a cryoprotectant or antifreeze for vital organs as well as in their muscle tissue. In this paper, we hypothesize that factors predisposing to elevated levels of glucose, glycerol and other sugar derivatives may have been selected for, in part, as adaptive measures in exceedingly cold climates. This cryoprotective adaptation would have protected ancestral northern Europeans from the effects of suddenly increasingly colder climates, such as those believed to have arisen around 14,000 years ago and culminating in the Younger Dryas. When life expectancy was short, factors predisposing to Type 1 diabetes provided a survival advantage. However, deleterious consequences of this condition have become significant only in more modern times, as life expectancy has increased, thus outweighing their protective value. Examples of evolutionary adaptations conferring selection advantages against human pathogens that result in deleterious effects have been previously reported as epidemic pathogenic selection (EPS). Such proposed examples include the cystic fibrosis mutations in the CFTR gene bestowing resistance to Salmonella typhi and hemochromatosis mutations conferring protection against iron-seeking intracellular pathogens. This paper is one of the first accounts of a metabolic disorder providing a selection advantage not against a pathogenic stressor alone, but rather against a climatic change. We thus believe that the concept of EPS should now include environmental factors that may be nonorganismal in nature. In so doing we propose that factors resulting in Type 1 diabetes be considered a result of environmental pathogenic selection (EnPS).

Acclimatization↗
PubMed2000

Accidental hypothermia in the elderly.

Accidental hypothermia is known to be a hazard to elderly people in temperate and cold climate. This is a review of the literature focusing on risk factors, clinical presentation and treatment of hypothermia in the elderly. The most important risk factors are connected to ageing itself and to the morbidity often found in elderly hypothermia victims. Knowledge about treatment of severe accidental hypothermia in elderly people is based on experience from few cases and some minor prospective studies mainly on rewarming of younger patients. Clinical treatment protocols seems to be based on experience from younger patients. Based on general knowledge in geriatric medicine and experience from three recent cases of hypothermia in the elderly, the use of careful, active external rewarming and a low stress strategy are recommended for elderly patients.

Age Factors↗
PubMed2005

A hyperactive, Ca2+-dependent antifreeze protein in an Antarctic bacterium.

In cold climates, some plants and bacteria that cannot avoid freezing use antifreeze proteins (AFPs) to lessen the destructive effects of ice recrystallization. These AFPs have weak freezing point depression activity, perhaps to avoid sudden, uncontrolled growth of ice. Here, we report on an uncharacteristically powerful bacterial AFP found in an Antarctic strain of the bacterium, Marinomonas primoryensis. It is Ca(2+)-dependent, shows evidence of cooperativity, and can produce over 2 degrees C of freezing point depression. Unlike most AFPs, it does not produce obvious crystal faceting during thermal hysteresis. This AFP might be capable of imparting freezing avoidance to M. primoryensis in ice-covered Antarctic lakes. A hyperactive bacterial AFP has not previously been reported.

Antarctic Regions↗
PubMed1998

Pituitary-gonadal hormones during prolonged residency in Antarctica.

Plasma luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL) and testosterone levels were measured in nine eugonadal men in New Delhi and during the 1st week of different months of their stay at Dakshin Gangotri in Antarctica. During their 12-month stay in Antarctica, they were exposed to a severely cold climate, long polar nights and polar days, high wind velocity, increased amounts of solar and ultraviolet radiation and geomagnetism, as well as physical and social isolation. Plasma testosterone tended to increase in March, but a significant increase (P < 0.05) was not seen until April. The mean testosterone levels in May, June, September and November were also significantly higher than the March or New Delhi values. The absolute values of LH, FSH and PRL did not show any month-to-month changes in Antarctica. However, when the hormone levels were expressed as a percentage of the individual annual Antarctic mean, significant differences as a percentage of the individual annual Antarctic mean, significant differences were observed. The testosterone peak in April, May and June was associated with an increase in LH. The nadirs of testosterone, LH, FSH and PRL were seen in either July or August. FSH showed the highest values in March, whereas the highest PRL values were seen in November. These observations suggest the presence of circannual variations in gonadotropin, PRL and LH in Antarctica which are independent of polar days and polar nights. It appears that factors other than the duration of daylight might be involved in regulating these changes. The significance of maintenance of testosterone levels in the supra-physiological range in Antarctica remains unknown but may be important in acclimatization/habituation to the extreme polar cold by increasing basal metabolic rate, protein synthesis and erythropoiesis.

Acclimatization↗
PubMed1994

Arrhythmias and ST segment deviation during prolonged exhaustive exercise (ski marathon) in healthy middle-aged men.

To evaluate the occurrence of arrhythmias and silent ischaemia during a prolonged exhaustive exercise in cold climate conditions, we monitored 37 healthy middle-aged men (age 40-56 years) who were randomly selected from participants of a ski marathon. Completing the 75-90 km race took 7-12 h. The highest and lowest mean hourly heart rates during skiing were 150 +/- 9 (mean +/- SD) and 138 +/- 11 beats.min-1. The maximum heart rate was 161 +/- 9 beats.min-1, and occurred in most skiers during the first hour. Ventricular premature complexes (VPCs) were present in 33 of 37 men (89%) with a median frequency of five beats during skiing (range 0-425). Complex forms occurred in eight men (22%), and atrial ectopics appeared in 33 of 35 participants (94%). The frequency of the arrhythmias did not increase over the skiing period. At control monitoring during a representative period the highest mean hourly heart rate was 74 +/- 12 beats.min-1 and VPCs were seen in 21 men (57%) at a median frequency of one beat during the control period (range 0-338) and complex forms occurred in three men (8%). Three men had asymptomatic ST segment depression of 0.2-0.3 mV lasting 2-10 min during the first hour of skiing. One of them had marginal ST segment depression (0.1 mV) at exercise electrocardiography, but all had normal results at exercise thallium scintigraphy and echocardiography. Thus, arrhythmias were significantly (P < 0.001) increased in middle-aged men during exhaustive prolonged exercise as compared to those observed during a similar period of time of normal daily life.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1963

COLD PANNICULITIS.

Explore the source record for details and available documents.

Black People↗