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PubMed2001

Persistence of both peripheral and non-peripheral corneodesmosomes in the upper stratum corneum of winter xerosis skin versus only peripheral in normal skin.

To understand the biochemical abnormalities that underlie the reduced desquamation observed in dry skin, we analyzed corneodesmosome degradation in normal and winter xerosis skin. Western blotting of total proteins from corneocytes obtained by varnish-strippings from the legs of 56 volunteers with normal (26) or xerotic (30) skin was performed using antibodies specific for (corneo)desmosome proteins. In the whole population, the amounts of desmoglein 1 and plakoglobin were found to be correlated, but were not related to the amounts of corneodesmosin. This suggests simultaneous proteolysis for the former proteins differing from that of corneodesmosin. Neither entire desmoplakins nor any proteolysis-derived fragments were detected. The amounts of corneodesmosin, desmoglein 1, and plakoglobin detected were found to be significantly higher in xerotic compared with normal skin extracts. Conventional and freeze-fracture electron microscopy showed the absence of nonperipheral corneodesmosomes in the upper stratum corneum of normal skin but the presence of a significant number of these structures in the same layer of winter xerosis skin. These results provide a more precise description of the proteolysis of corneodesmosome components in the upper cornified layer of the epidermis. They support previous studies demonstrating the importance of corneodesmosome degradation in desquamation and reveal that the nonperipheral corneodesmosomes, which are totally degraded during maturation of the stratum corneum in normal skin, persist in winter xerosis, probably leading to abnormal desquamation.

Adult↗
PubMed2003

Serious winter sport injuries in children and adolescents requiring hospitalization.

To describe the epidemiology of serious winter sports-related injuries resulting in hospitalization in children and adolescents, we prospectively collected and analyzed records of all winter sports-related injuries requiring hospitalization at our respective institutions from 1996 to 2000. We identified 101 patients with a mean age of 10.7 years, of whom 68% were male and 32% female. Skiers accounted for 71% and snowboarders 26% of injuries; 3% of injuries were snowmobile-or luge-related. Leading mechanisms of injury were ground level falls (50%), crashes into trees, (18%), and falls from ski lift (13%). Approximately 26% of the patients met criteria for trauma-team activation. Leading diagnoses were head injury (20%), femur fracture (18%), and concussion (11%). Five patients required admission to the intensive care unit. The median injury severity score (ISS) was 7; 8% of patients had an ISS score > 15. Abbreviated Injury Scale-1990 scores of > or = 3 were noted in 34% of the patients. We conclude that Injuries sustained through participation in winter sports may be severe, especially in the case of injuries involving the head. Injury-prevention strategies should focus on head injuries.

Abbreviated Injury Scale↗
PubMed1987

[Wrist para-articular radius fractures in winter sports].

Winter sport is of great importance in the Alpine countries. In 1980 3600 persons (10.24%) of all new admittances hospitalized in our hospital were injured when practicing winter sports. In 1983 they lessened to 2597 (7.73%) and in 1985 2999 (5.74%). Analysis of all injuries caused by winter sport activities shows that the number of injured persons is decreasing, severity of the injuries however, increasing. A comparison of the distal radius fractures in 1980, 1983 and 1985 indicates that extraarticular metaphyseal fracture types have decreased, intraarticular fracture with multiple fragments however, have increased. Mainly younger patient suffer from severe fractures. We regard the high pace-risk of the age group as the main course of this fact.

Adolescent↗
PubMed1990

Differences in the quality of semen in outdoor workers during summer and winter.

BACKGROUND AND METHODS: In warm climates throughout the world, there is a deficit of births during the spring season. To determine whether this deficit might reflect a deleterious effect of heat on the male reproductive capacity during the previous summer, we obtained semen specimens in summer and winter from normal men who worked outdoors in the vicinity of San Antonio, Texas, and we performed automated semen analyses with an image-analysis system. RESULTS: Pairwise comparisons among 131 men without azoospermia who contributed specimens in both summer and winter revealed significant reductions during the summer in sperm concentration, total sperm count per ejaculate, and concentration of motile sperm. The mean decreases in these values after adjustment for potential confounding characteristics were 32 percent (95 percent confidence limits, 28 and 44 percent), 24 percent (95 percent confidence limits, 18 and 43 percent), and 28 percent (95 percent confidence limits, 24 and 44 percent), respectively (P less than 0.0001). The lower a subject's average sperm concentration and motile-sperm concentration, the greater the reduction. We found no correlation, however, between the number of hours per day spent working during summer in settings without air conditioning and either the summer sperm concentration or the difference in concentration between summer and winter. Among the children of the men in the study whose wives were living near San Antonio during the year before they gave birth, a disproportionately low number were born during the spring. CONCLUSIONS: Semen quality deteriorates during the summer. This phenomenon may account at least in part for the reduction in the birth rate during the spring in regions with warm climates.

Adult↗
PubMed2001

Antibody responses to bacteriophage phi X-174 in human subjects exposed to the antarctic winter-over model of spaceflight.

BACKGROUND: It has been proposed that exposure to long-term spaceflight conditions (stress, isolation, sleep disruption, containment, microbial contamination, and solar radiation) or to ground-based models of spaceflight will alter human immune responses, but specific antibody responses have not been fully evaluated. OBJECTIVE: We sought to determine whether exposure to the 8-month Antarctic winter-over model of spaceflight would alter human antibody responses. METHODS: During the 1999 Australian National Antarctic Research Expeditions, 11 adult study subjects at Casey, Antarctica, and 7 control subjects at Macquarie Island, sub-Antarctica, received primary and secondary immunizations with the T cell-dependent neoantigen bacteriophage phi X-174. Periodic plasma samples were analyzed for specific antibody function. RESULTS: All of the subjects from Casey, Antarctica, cleared bacteriophage phi X-174 normally by 1 week after primary immunization, and all had normal primary and secondary antibody responses, including immunologic memory amplification and switch from IgM to IgG antibody production. One subject showed a high normal pattern, and one subject had a low normal pattern. The control subjects from Macquarie Island also had normal immune responses to bacteriophage phi X-174. CONCLUSIONS: These data do not support the hypothesis that de novo specific antibody responses of subjects become defective during the conditions of the Antarctic winter-over. Because the Antarctic winter-over model of spaceflight lacks the important factors of microgravity and solar radiation, caution must be used in interpreting these data to anticipate normal antibody responses in long-term spaceflight.

Adult↗
PubMed2005

Effects of supplementary food on the winter inhibition of reproduction in male and female four-striped field mice (Rhabdomys pumilio).

The effects of winter food supplementation on reproduction in the seasonally breeding four-striped field mouse Rhabdomys pumilio were investigated at Mountain Zebra National Park in the Eastern Cape Province of South Africa. On both control and supplemented grids, reproductive activity in females was inhibited; no pregnant females were collected and juveniles were only present in the first winter month. The provision of additional food resulted in an increase in body mass and mass of the male and female reproductive organs. However, all males, from both grids, were spermatogenically active. Ovarian activity was not stimulated by the provision of additional food, but the development of the uterus was and the endometrium was thicker and more vascularised in mice from the supplemented grid than from the control grid. We conclude that seasonal reproduction in R. pumilio is controlled by the females, in which reproductive activity is inhibited in winter. However, the provision of supplementary food was not sufficient to override the reproductive inhibition.

Animals↗
PubMed1988

Hatchling turtles survive freezing during winter hibernation.

Hatchlings of the painted turtle (Chrysemys picta marginata) are unique as the only reptile and highest vertebrate life form known to tolerate the natural freezing of extracellular body fluids during winter hibernation. Turtles survived frequent exposures to temperatures as low as -6 degrees C to -8 degrees C in their shallow terrestrial nests over the 1987-1988 winter. Hatchlings collected in April 1988 had a mean supercooling point of -3.28 +/- 0.24 degrees C and survived 24 hr of freezing at -4 degrees C with 53.4% +/- 1.98% of total body water as ice. Recovery appeared complete after 20 hr of thawing at 3 degrees C. However, freezing at -10.9 degrees C, resulting in 67% ice, was lethal. A survey of possible cryoprotectants revealed a 2- to 3-fold increase in glucose content of liver and blood and a 3-fold increase in blood glycerol in response to freezing. Although quantitatively low, these responses by spring turtles strongly indicate that these may be the winter-active cryoprotectants. The total amino acid pool of blood also increased 2.25-fold in freezing-exposed turtles, and taurine accounted for 52% of the increase. Most organs accumulated high concentrations of lactate during freezing, a response to the ischemic state imposed by extracellular freezing. Changes in glycogen phosphorylase activity and levels of glucose 6-phosphate and fructose 2,6-bisphosphate were also consistent with a dependence on anaerobic glycolysis during freezing. Studies of the molecular mechanisms of natural freeze tolerance in these turtles may identify protective strategies that can be used in mammalian organ cryopreservation technology.

Animals↗
PubMed2005

Winter survival of larvae and pupae of the blowfly, Lucilia sericata (Diptera: Calliphoridae).

The mortality of larvae and pupae of the blowfly Lucilia sericata (Meigen) were examined during winter and spring, for two or three years. In soil cores in the field, 70-95% of the larvae died overwinter. Larvae congregated in the top 10 cm of the soil core and did not move extensively throughout the column during the winter. Larvae and pupae at greater depth were less likely to pupariate and emerge successfully than larvae closer to the surface. Under semi-natural conditions, where pupae were placed outside in sawdust filled tubes, in the absence of the usual biotic mortality factors, the mortality of larvae was considerably lower and was also unaffected by low winter temperatures. Hence, low temperatures did not appear to be the primary cause of high overwintering mortality in the field which, it is suggested, is more likely to be the result of the action of biotic mortality factors, such as entomopathogenic nematodes and fungi.

Animals↗
PubMedDate not supplied

Dark Winter and the spring of 1972: deflecting the social lessons of smallpox.

This article examines how the master status of bioterrorism has distracted professional and political attention from the social lessons of smallpox. I illustrate this by comparing an influential bioterrorism simulation known as Dark Winter with the social history surrounding the Yugoslavian smallpox epidemic of 1972. Dark Winter's epidemiological premises were largely based upon what was learned from the Yugoslavian outbreak. Yet, although this epidemic was non-deliberate, the exercise did not attend to the social conditions within which it developed. Most notably, it did not consider that this epidemic was mainly borne by marginalized communities of Kosovan Albanians and that difficulties in controlling it were linked to the relative lack of pre-existing public health infrastructure among these people; instead, the Dark Winter exercise mainly focused upon the proximate determinants of violence and its immediate management. This distraction from the social dynamics of infectious diseases has major implications for the prevention and management of future outbreaks, regardless of whether or not they are deliberately initiated.

Bioterrorism↗
PubMedDate not supplied

A randomized, controlled lower leg growth study of vitamin D supplementation to healthy children during the winter season.

BACKGROUND: The deceleration of longitudinal growth in children during winter occurs simultaneously with a decrease in the number of daylight hours and a reduction in vitamin D status. Due to worries about deleterious effects on bone of a relative insufficiency, vitamin D supplementation to healthy children has been suggested. AIM: To see whether supplementation of vitamin D to healthy children during winter affects seasonal growth. SUBJECTS AND METHODS: Twelve girls and eight boys aged 6.2-13.7 (mean 9.8) years, all healthy, were enrolled in a double-blind, randomized, placebo-controlled cross-over study with two 4-week treatment periods and 2-week run-in and wash-out periods. Vitamin D(3) 600 IU was given in one tablet ABCDin daily. Knemometry of the right lower leg was performed on the first and last day of each period. RESULTS: Lower leg growth rates (mean +/- SEM) during placebo and vitamin D(3) administration were identical: 0.28 +/- 0.04 mm per week (p = 0.94, t = 0.1, 95% CI: - 0.12-0.13 mm per week). CONCLUSION: Supplementation with vitamin D(3) 600 IU day(-1) to healthy children during winter may not improve seasonal growth. Therefore, supplementation may not be recommended on the grounds of concerns about growth; however firm conclusions await randomized long-term studies.

Adolescent↗
PubMed1997

Characteristics of winter and summer aerosol mass and light extinction on the Colorado plateau.

This paper focuses on the spatial variability of fine mass and extinction budgets taking data from the winter and summer months of 1992. The study area included southern California, southern Nevada, southern Utah, Arizona, and parts of New Mexico. Two types of monitoring sites were operated: intensive and secondary or satellite. At the intensive sites, all major aerosol species were measured as well as extinction or scattering. At the satellite sites, trace elements including sulfur and hydrogen, absorption, and gravimetric fine mass were measured. Where all aerosol species are measured, the spatial variability of extinction budgets is examined assuming an externally mixed aerosol. At the satellite sites, an approximated fine mass budget is derived and the variability of these budgets in space and time are examined. This effort was part of a study called Project MOHAVE (Measurement of Haze and Visual Effects) carried out with the principal objective of understanding the relative contribution of regional and local sources to visibility impairment on the Colorado Plateau and specifically, the Grand Canyon. Generally, the contribution of sulfates, organics, and absorption to extinction are about equal at 20-30% with the coarse mass fraction being about 10-20%. The one exception is in southern California where the nitrate contribution tends to be higher in the winter than summer. During the summer, concentration gradients tend to be spread out across the study area, while during the winter months, variability in concentration and budgets tends to occur on a smaller scale.

Aerosols↗
PubMed2005

Summer and winter nonmethane hydrocarbon emissions from on-road motor vehicles in the Midwestern United States.

On-road vehicle emission rates of nonmethane hydrocarbons (NMHCs) were measured in two tunnels in Milwaukee, WI, in summer 2000 and winter 2001. Seasonal ambient temperatures in the Midwestern United States vary more widely than in locations where most studies of NMHC emissions from vehicle fleets have been conducted. Ethanol is the added fuel oxygenate in the area, and, thus, emissions measured here are of interest as other regions phase out methyl tertiary butyl ether and increase the use of ethanol. Total emissions of NMHCs in three types of tunnel tests averaged 4560 +/- 800 mg L(-1) fuel burned (average +/- standard error). To investigate the impact of cold start on vehicle emissions, samples were collected as vehicles exited a parking structure in subzero temperatures. NMHC emissions in the subzero cold-start test were 8830 +/- 190 mg L(-1) fuel-nearly double the tunnel emissions. Comparison of ambient data for the Milwaukee area with tunnel emissions showed the impact of seasonal differences in fuels and emissions on the urban atmosphere. Composition of fuel samples collected from area gas stations in both seasons was correlated with vehicle emissions; the predominant difference was increased winter emissions of lighter hydrocarbons present in winter gasoline. A chemical mass balance model was used to determine the contributions of whole gasoline and gasoline headspace vapors to vehicle emissions in the tunnel and cold-start tests, which were found to vary with season. Results of the mass balance model also indicate that partially combusted components of gasoline are a major contributor to emissions of aromatic compounds and air toxic compounds, including benzene, toluene, xylenes, napthalene, and 1,3-butadiene, whereas air toxics hexane and 2,2,4-trimethylpentane are largely attributed to gasoline and headspace vapors.

Air Pollutants↗
PubMed2006

Processes influencing secondary aerosol formation in the San Joaquin Valley during winter.

Air quality data collected in the California Regional PM10/ PM(2.5) Air Quality Study (CRPAQS) are analyzed to qualitatively assess the processes affecting secondary aerosol formation in the San Joaquin Valley (SJV). This region experiences some of the highest fine particulate matter (PM(2.5)) mass concentrations in California (< or = 188 microg/m3 24-hr average), and secondary aerosol components (as a group) frequently constitute over half of the fine aerosol mass in winter. The analyses are based on 15 days of high-frequency filter and canister measurements and several months of wintertime continuous gas and aerosol measurements. The phase-partitioning of nitrogen oxide (NO(x))-related nitrogen species and carbonaceous species shows that concentrations of gaseous precursor species are far more abundant than measured secondary aerosol nitrate or estimated secondary organic aerosols. Comparisons of ammonia and nitric acid concentrations indicate that ammonium nitrate formation is limited by the availability of nitric acid rather than ammonia. Time-resolved aerosol nitrate data collected at the surface and on a 90-m tower suggest that both the daytime and nighttime nitric acid formation pathways are active, and entrainment of aerosol nitrate formed aloft at night may explain the spatial homogeneity of nitrate in the SJV. NO(x) and volatile organic compound (VOC) emissions plus background O3 levels are expected to determine NO(x) oxidation and nitric acid production rates, which currently control the ammonium nitrate levels in the SJV. Secondary organic aerosol formation is significant in winter, especially in the Fresno urban area. Formation of secondary organic aerosol is more likely limited by the rate of VOC oxidation than the availability of VOC precursors in winter.

Aerosols↗
PubMed1992

Metal levels in regrown feathers: assessment of contamination on the wintering and breeding grounds in the same individuals.

Birds are useful indicators of environmental contamination because they are relatively large, conspicuous, top predators in food chains. However, concentrations of contaminants in a bird's tissues reflect the bird's exposure over wide temporal and spatial scales. Birds are most useful as monitors of exposure when these scales are known. In this paper we report concentrations of lead, cadmium, mercury, and selenium in breast feathers of common terns (Sterna hirundo) and roseate terns (S. dougallii) trapped during incubation at breeding colonies in New York and Massachusetts. Terns arrived on the breeding grounds with breast feathers grown on their wintering grounds, and regrew certain feathers that were plucked for analysis. The regrown feathers were themselves plucked, and both sets of feathers were analyzed. For roseate terns at Cedar Beach and common terns at both sites there was a significant increase in mercury levels in the feathers grown on the breeding grounds compared to those grown on the wintering ground. The differences in mercury were far greater at Bird Island than at Cedar Beach. Selenium levels at Cedar Beach were higher for the regrown feathers than the initial feathers for roseate terns, but not for common terns. Lead and cadmium levels were not significantly different at either site for either species. These results suggest that terns are exposed to significantly higher levels of mercury in the northeastern United States than they are in the wintering grounds in South America.

Animals↗
PubMed1979

[The supply of wild ruminants with major and trace elements. 2. The manganese content of winter grazing and the manganese status of red deer, fallow deer, roes and mouflons].

The winter grazing of wild ruminants on mantles of slate waste in the Harz mountains and in Gera county were richest in Mn whereas those on mantles of granite waste in the Erzgebirge were poorest. The flora of the shell-limestone, keuper and loess areas contains much less Mn than that of those acid habitats. The Mn-requirement of the wild ruminants grazing in the forests is met however, since bilberry plants (2,080 mg/kg), spruce twigs (984 mg/kg), spruce bark (827 mg/kg), oak twigs (791 mg/kg) and heather (754 mg/kg dry matter) in addition to many other plant species store extremely high amounts of Mn. Solely sallow twigs were poor in Mn (28 mg/kg). Based on 601 samples examined, the Mn supply of wild ruminants is extensively described. The rumen content reflected the plentiful Mn-supply of the wild ruminants living in forests (greater than 400 mg/kg) and the far worse one of field roes, particularly in Mn-deficiency areas for domesticated ruminants (mantle of shell-limestone waste 37 mg Mn/kg dry matter of rumen content). The indicator organs of the Mn-status (liver, covering hair, kidneys) verify the statements made concerning red deer, fallow deer and mouflons, of which a total of 170 head from 14 biotopes were examined. An Mn-deficit of field roes in Mn-deficiency habitats in winter cannot completely be excluded. Mouflons have not yet been able to adapt themselves to the excessive Mn-supply of the acid forest habitats in Central Europe. They stored significantly higher amounts of Mn in liver, covering hair, kidneys, cerebrum and ribs than the other wild ruminants and sheep and cattle. The normal Mn-content of the liver and the cerebrum of red deer, fallow deer and roes corresponds to that of sheep and cattle. Roes and fallow deer have winter covering hair poor in Mn (less than 4.0 mg/kg) in comparison to sheep and cattle.

Animal Nutritional Physiological Phenomena↗
PubMed2003

Winter respiratory viruses and health care use: a population-based study in the northwest United States.

To quantify health care use among adults during influenza and respiratory syncytial virus (RSV) seasons, we identified a cohort of veterans aged >or=18 years who used Department of Veterans Affairs (VA) facilities in Oregon and Washington states as their source of health care. During 1998-2000, veterans accrued 237,159 person-years of follow-up. Using VA data sources, we measured acute cardiopulmonary hospitalizations and primary care and urgent care visits. Differences between rates of study events when influenza and/or RSV were circulating and event rates when neither virus was circulating were used to calculate winter virus-attributable morbidity. Inpatient and outpatient event rates were consistently higher during winter virus season, compared with non-winter virus season. Annual rates of cardiopulmonary hospitalizations attributable to influenza or RSV infection ranged from 0.8 (95% confidence interval [CI], 0.1-1.5) per 1000 low-risk individuals aged 18-49 years, to 10.6 (95% CI, 7.5-13.6) per 1000 high-risk individuals aged >or=65 years. Each year, circulation of influenza and RSV coincide with predictable increases in medical care use.

Adolescent↗
PubMed2006

Body protein stores and isotopic indicators of N balance in female reindeer (Rangifer tarandus) during winter.

We studied bred and unbred female reindeer (Rangifer tarandus tarandus) during 12 wk of winter when ambient temperatures were low and nitrogen (N) demand for fetal growth is highest in pregnant females. Animals were fed a complete pelleted diet ad lib. that contained 2.54% N in dry matter that was 80% +/- 2% (X +/- SD) digestible. Female reindeer lost 64% +/- 14% of body fat but gained 34% +/- 11% of lean mass from 10 wk prepartum to parturition. These changes were equivalent to average balances of -14.14 +/- 2.35 MJ d(-1) and 10 +/- 3 g N d(-1). Blood cells, serum, and urine declined in (15)N/(14)N in late winter as body protein was gained from the diet. Blood cells of newborn calves were more enriched in (15)N and (13)C than that of their mothers, indicating the deposition of fetal protein from maternal stores. To quantify pathways of N flow in reindeer, N balance was measured by confining animals to cages for 10 d at 4 wk from parturition. N balance was inversely related to (15)N/(14)N in urea-N but not related to (15)N/(14)N of blood cells, creatinine, and feces. The proportion of urea-N derived from body protein increased above 0.46 as N balance fell below -200 mg N kg(-0.75) d(-1). Proportions of urea-N from body protein were -0.01 +/- 0.21 in pregnant females before and after caging and were consistent with average body protein gain in winter. Storage of protein allows reindeer and caribou to tolerate diets that are low in N without impairing fetal development.

Alaska↗
PubMed2004

Influenza and the winter increase in mortality in the United States, 1959-1999.

In economically developed countries, mortality increases distinctly during winter. Many causes have been suggested, including light-dark cycles, temperature/weather, and infectious agents. The authors analyzed monthly mortality in the United States during the period 1959-1999 for four major disease classes. The authors isolated the seasonal component of mortality by removing trends and standardizing the time series. They evaluated four properties: coincidence in mortality peaks, autocorrelation structure and autoregressive integrated moving average (ARIMA) models, magnitude, and age distribution. Peak months of mortality for ischemic heart disease, cerebrovascular disease, and diabetes mellitus coincided appropriately with peaks in pneumonia and influenza, and coefficients of autocorrelation and ARIMA models were essentially indistinguishable. The magnitude of the seasonal component was highly correlated with traditional measures of excess mortality and was significantly larger in seasons dominated by influenza A(H2N2) and A(H3N2) viruses than in seasons dominated by A(H1N1) or B viruses. There was an age shift in mortality during and after the 1968/69 pandemic in each disease class, with features specific to influenza A(H3N2). These findings suggest that the cause of the winter increase in US mortality is singular and probably influenza. Weather and other factors may determine the timing and modulate the magnitude of the winter-season increase in mortality, but the primary determinant appears to be the influenza virus.

Aged↗