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PubMed1992

Survival rates of some terrestrial microorganisms under simulated space conditions.

In connection with planetary quarantine, we have been studying the survival rates of nine species of terrestrial microorganisms (viruses, bacteria, yeasts, fungi, etc.) under simulated interstellar conditions. If common terrestrial microorganisms cannot survive in space even for short periods, we can greatly reduce expenditure for sterilizing space probes. The interstellar environment in the solar system has been simulated by low temperature, high vacuum (77 k, 4 x 10(-6) torr), and protons irradiation from a Van de Graaff generator. After exposure to a barrage of protons corresponding to about 250 years of irradiation in solar space, Tobacco mosaic virus, Bacillus subtilis spores, Aspergillus niger spores and Clostridiun mangenoti spores showed survival rates of 82%, 45%, 28%, and 25%, respectively. Furthermore. pathogenic Candida albicans showed 7% survival after irradiation corresponding to about 60 years in space.

Bacteria↗
PubMed1977

Determination of mercury in fish from rivers and lakes in Hungary by atomic absorption technique.

In 1975, in cooperation with 8 County Hygienic Stations, total mercury content in fish from rivers and lakes in Hungary was measured. The mercury content in fish muscle-tissue from 164 fish samples averaged 0.36 mg/kg. Average levels in different fish species ranged from 0.10 to 0.57 mg/kg. The amount of mercury in fish from rivers and lakes, with the exception of the Danube, was, in general, lower than the tolerance level (0.50 mg/kg) as adopted in many countries. Mercury levels in fish from Lake Balaton did not amount to more than 0.30 mg/kg. The circulating cold vapour atomic absorption method was used to determined the mercury content in the fish samples.

Animals↗
PubMed1990

Immunosuppression in mice induced by cold water stress.

A number of studies indicate that stress can result in suppression of the immune system in animals and man. Most of the studies have focused on alterations of lymphocyte function while only a few have investigated alterations of macrophage function or macrophage cytokine production. Macrophages play an essential role in homeostasis of the immune response. Indeed, the earliest events of the immune response occur in cells of the monocytic lineage, and their secretion of various cytokines may have both immunological and nonimmunological effects. The present studies were undertaken to determine whether alterations in macrophage physiology occur in mice subjected to a stress stimulus. Our studies in mice exposed to cold water stress for 4 days indicated reduced numbers of thymocytes and splenocytes, decreased T-cell blastogenesis, and reduced NK activity. Examination of elicited peritoneal macrophages from stressed mice revealed increased prostaglandin E2 (PGE2) secretion and decreased immune region associated antigen (Ia) expression in response to interferon-gamma. Despite elevated PGE2 levels, indomethacin was generally unable to restore depressed immune function. Of special interest was the finding that cell-associated and secreted interleukin 1 were significantly higher from unstimulated elicited macrophages from stressed mice. These results suggest that early in the response to stress, functions of a variety of cells within the immune system, especially macrophages, are altered and that dysregulated macrophage function may well contribute to the generalized suppression of the immune response in cold water stressed mice.

Animals↗
PubMed1971

Temperature Physiology of the Sea Snake Pelamis platurus: An Index of Its Colonization Potential in the Atlantic Ocean.

The yellow-bellied sea snake Pelamis platurus occurs throughout the tropical Indian and Pacific Oceans from east Africa to Central America. Its latitudinal distribution limits coincide with the 18 degrees C surface isotherm. P. platurus has upper and lower thermal tolerances of 36.0 and 11.7 degrees C. With rapid cooling, P. platurus stops feeding at 16-18 degrees C; however, it has a high resistance to cold temperature and can withstand 5 degrees C for 1 hr. After 10 days' exposure, P. platurus does not acclimate to 17 degrees C and, thus, would not be able to survive for long periods in water this cold.In the event of its transit through the proposed Central American Sea-Level Canal, P. platurus would colonize the Atlantic Ocean and, during the summer months, would be able to extend its north Atlantic distribution to as far as Cape Cod and the English Channel.

Journal Article↗
PubMedDate not supplied

Sex, gender, and blood pressure: contributions to experimental pain report.

OBJECTIVE: The current study investigated whether the relationship between sex and experimental pain report was explained by systolic blood pressure (SBP) at rest or during pain task, by gender-role socialization as assessed by the Bem Sex Role Inventory, or both. The influence of gender-role socialization on pain report is often inferred but rarely studied. METHODS: Fifty female and 54 male healthy, young adults completed the Bem Sex Role Inventory and then underwent a cold pressor task. Blood pressure was assessed before and during pain testing. RESULTS: Univariate analyses indicated significant sex-related differences in pain threshold and pain tolerance. Baseline SBP was positively related to pain tolerance but did not explain sex differences, in accord with previous research. The Bem Sex Role Inventory demonstrated a relationship with pain, but did not explain sex differences. CONCLUSIONS: We suggest that context-specific measures of gender are needed to assess gender-related pain behaviors in specific situations. Results from the current study support our contention that gender is part of sex as commonly measured. Also, blood pressure does not appear to fully account for sex-related differences in pain.

Adolescent↗
PubMed1987

Improved results in pancreatic transplantation by avoidance of nonimmunological graft failures.

Twenty eight consecutive combined renal and pancreatic transplantations with enteric exocrine diversion were performed between June 1984 and May 1986. The one-year actuarial patient survival and renal and pancreatic graft survival were 90%, 67%, and 69%, respectively. Nineteen pancreatic grafts and eighteen renal grafts are currently functioning at 1-24 months. Of the pancreatic graft losses only 2 were attributable to nonimmunological complications. No pancreatic graft was lost due to pancreaticoenteric leakage or vascular thrombosis. This was achieved by reducing the cold ischemia time and by adopting an aggressive anticoagulant policy. In all patients with functioning grafts the fasting blood glucose, glycosylated hemoglobin level, and oral glucose tolerance test were normal. The intravenous glucose tolerance test was normal in most of the patients but subnormal in some.

Adult↗
PubMed2005

The importance of good hydration for work and exercise performance.

This review covers published literature on the influence of whole-body hydration status on exercise performance. The majority of information in this area relates to endurance exercise performance, but information on power, strength, and sporting skills has also been investigated. These areas form the focus of the current review. It is apparent that some individuals can tolerate body water losses amounting to 2% of body mass without significant risk to physical well-being or endurance exercise performance when the environment is cold (for example 5 degrees C-10 degrees C) or temperate (for example 20 degrees C-22 degrees C). However, when exercising in a hot environment (an environmental temperature of 30 degrees C or more), dehydration by 2% of body mass impairs exercise performance and increases the possibility of suffering a heat injury.

Body Temperature Regulation↗
PubMed2006

Defective lipolysis and altered energy metabolism in mice lacking adipose triglyceride lipase.

Fat tissue is the most important energy depot in vertebrates. The release of free fatty acids (FFAs) from stored fat requires the enzymatic activity of lipases. We showed that genetic inactivation of adipose triglyceride lipase (ATGL) in mice increases adipose mass and leads to triacylglycerol deposition in multiple tissues. ATGL-deficient mice accumulated large amounts of lipid in the heart, causing cardiac dysfunction and premature death. Defective cold adaptation indicated that the enzyme provides FFAs to fuel thermogenesis. The reduced availability of ATGL-derived FFAs leads to increased glucose use, increased glucose tolerance, and increased insulin sensitivity. These results indicate that ATGL is rate limiting in the catabolism of cellular fat depots and plays an important role in energy homeostasis.

Adipocytes↗
PubMed1985

Evaluation of growth, hormonal, and hematological responses of neonatal chickens to reduced temperature brooding.

A series of experiments was conducted to examine the response of neonatal, male broiler chicks to brooding at a reduced temperature. In Trials 1 and 2, chicks brooded at 26.7 C generally had lower body weights and higher serum corticosterone levels during the first week after hatch than those brooded at 32.2 C. However, significant differences in body weight were observed only on Day 6 in Trial 1 and on Days 1 and 5 in Trial 2. Serum corticosterone levels, likewise, were not significantly different on all days in Trials 1 and 2. These hormone levels were statistically different on Days 1 and 5 in Trial 1 and on Days 1 and 3 in Trial 2. Brooding neonates at 26.7 C for 3 days in Trials 3 and 4 resulted in consistently lower body weights and gain and higher serum corticosterone, thyroxine, total protein, albumin, and globulin. Serum growth hormone levels in chicks brooded at 26.7 C were initially depressed the first day but were elevated on the 2 subsequent days, compared with chicks brooded at 32.2 C. Considering the physiological importance of corticosterone and thyroxine in the adaptation of chickens to cold environmental temperatures, it would be useful to evaluate the genetic variation associated with the responsiveness of these hormones in a randombred population and to improve tolerance of neonatal chickens to reduced temperature brooding through selection.

Animals↗
PubMed1982

The influence of low temperature on the radiation sensitivity of enzymes.

When enzymes are exposed to ionizing radiation at low temperatures there is a progressive decrease in radiation sensitivity: considerably more enzymatic activity remains after the same dose of radiation at low temperature compared to room temperature. Detailed studies of five enzymes reveals the quantitative relationship between radiation sensitivity and temperature during exposure. Although 25 enzymes are shown to display this same relationship, recent reports have denied this effect in three enzymes. In this paper, we investigate two possible artifacts that could cause these discrepancies: 1) inaccurate determination of the temperature of the sample during irradiation, and 2) use of temperature-sensitive dosimeters to measure radiation dose. Procedures are described that carefully control these parameters. Thermoluminescent dosimeters are shown to be independent of temperature effects. These methods are used to investigate one of the enzymes, malate dehydrogenase, that has been reported to have a temperature-insensitive radiation inactivation. The radiation sensitivity of this enzyme is found to show the same temperature dependence as 24 other enzymes.

Cold Temperature↗
PubMed2003

Remodelling of membrane phospholipids during transition to diapause and cold-acclimation in the larvae of Chymomyza costata (Drosophilidae).

The composition of molecular species of phosphatidylethanolamines (PEs) and phosphatidylcholines (PCs) was analysed in fat body and muscle tissues of Chymomyza costata larvae of different physiological states that markedly differed in their level of freeze-tolerance. Actively moving and feeding 3rd instar larvae had low (zero) capacity of freeze-tolerance and similar phospholipid (PL) compositions irrespective of their developmental destiny (non-diapause vs. diapause). Extensive remodelling of PL composition was found in these larvae in response to: (a) chilling of non-diapause larvae at 5 degrees C for 1 month; (b) developmental transition to diapause; and (c) chilling of diapause larvae. Transition to diapause and chilling led to an increase in freeze-tolerance. The increase in molar proportion of molecular species containing palmitic/linoleic (16:0/18:2) fatty acyls (FAs) esterified to sn-1/sn-2 positions of glycerol was the most prominent change, which was tightly statistically correlated with increasing freeze-tolerance. The increase of PLs with combination of 16:0/18:2 FAs was registered consistently in PEs and PCs in fat body and muscle tissues in response to chilling and to diapause onset. This increase was countered by a decreases of various molecular species, depending on tissue and lipid class. Most decreasing species shared one common theme: they had a saturated FA (palmityl, margaryl, stearyl) esterified at sn-1 position and a monounsaturate (palmitoleyl, oleyl) esterified at sn-2 position of glycerol. Possible adaptive meaning of PL molecular species remodelling is discussed.

Acclimatization↗
PubMed1986

Metabolic arrest.

In hypoxia sensitive cells and tissues, the rates of glucose and O2 consumption are inversely related (Pasteur Effect). Under O2 limiting conditions the demands for glucose (glycogen) in such cells may drastically rise as a means for maintaining ATP turnover close to normoxic rates; nevertheless ion and electrical potentials cannot be sustained due to energy insufficiency and high membrane permeability; metabolic and membrane functions, in effect, are decoupled. 'Good' animal anaerobes resolve these problems with a number of biochemical and physiological mechanisms; of these metabolic arrest and stabilized membrane functions are the most effective strategies for extending hypoxia tolerance. Metabolic arrest is achievable by means of a reversed or negative Pasteur Effect (reduced or unchanging glycolytic flux at reduced O2 availability) while coupling of metabolic and membrane function is achievable in spite of the lower energy turnover rates by maintaining membranes of low permeability (probably via reduced densities of ion-specific channels). Although the strategy of combining metabolic arrest with channel arrest has been recognized as a possible intervention, to date success has been minimal, mainly because cold depression of metabolism is the usual arrest mechanism used and this hypothermia in itself perturbs controlled cell function in most endotherms. The only endothermic systems currently known which appear able to use the dual strategy for extending hypoxia tolerance are hypoperfused hypometabolic tissues and organs of diving marine mammals.

Acute Kidney Injury↗
PubMed2006

Wheat EST resources for functional genomics of abiotic stress.

BACKGROUND: Wheat is an excellent species to study freezing tolerance and other abiotic stresses. However, the sequence of the wheat genome has not been completely characterized due to its complexity and large size. To circumvent this obstacle and identify genes involved in cold acclimation and associated stresses, a large scale EST sequencing approach was undertaken by the Functional Genomics of Abiotic Stress (FGAS) project. RESULTS: We generated 73,521 quality-filtered ESTs from eleven cDNA libraries constructed from wheat plants exposed to various abiotic stresses and at different developmental stages. In addition, 196,041 ESTs for which tracefiles were available from the National Science Foundation wheat EST sequencing program and DuPont were also quality-filtered and used in the analysis. Clustering of the combined ESTs with d2_cluster and TGICL yielded a few large clusters containing several thousand ESTs that were refractory to routine clustering techniques. To resolve this problem, the sequence proximity and "bridges" were identified by an e-value distance graph to manually break clusters into smaller groups. Assembly of the resolved ESTs generated a 75,488 unique sequence set (31,580 contigs and 43,908 singletons/singlets). Digital expression analyses indicated that the FGAS dataset is enriched in stress-regulated genes compared to the other public datasets. Over 43% of the unique sequence set was annotated and classified into functional categories according to Gene Ontology. CONCLUSION: We have annotated 29,556 different sequences, an almost 5-fold increase in annotated sequences compared to the available wheat public databases. Digital expression analysis combined with gene annotation helped in the identification of several pathways associated with abiotic stress. The genomic resources and knowledge developed by this project will contribute to a better understanding of the different mechanisms that govern stress tolerance in wheat and other cereals.

Acclimatization↗
PubMed2004

Relationship between alcohol dehydrogenase activity and low-temperature in two maize genotypes, Silverado F1 and Adh1-Adh2- doubly null.

We have examined the role of alcohol dehydrogenase (ADH, E.C.1.1.1.1) in chilling tolerance using maize (Zea mays L.) Adh1(-)Adh2(-) doubly null mutant. Adh1(-)Adh2(-) doubly null seedlings were found to have lowered survival rates compared to non-doubly null maize seedlings (Silverado F(1)) when held at 2 degrees C for varying periods. Exposure to ethanol did not increase the chilling tolerance in either Silverado F(1) or Adh1(-)Adh2(-) doubly null. ADH activity in Silverado F(1) remained steady when held at 2 degrees C for up to 3 d. ADH1 protein accumulation in chilled Silverado F(1) seedlings remained unchanged throughout the period of cold exposure. Chilling led to a significant inhibition of the P-H(+)-ATPase (E.C. 3.6.3.6) activity in Adh1(-)Adh2(-)doubly null, but minimal inhibition was seen in Silverado F(1). Though P-H(+)-ATPase activity in Adh1(-)Adh2(-) decreased, P-H(+)-ATPase protein levels remained constant during the chilling period. Levels of ATP slightly fluctuated in both types of seedlings during the duration of chilling. Lipid peroxidation levels in Adh1(-)Adh2(-) doubly null increased with chilling exposure, but not in the Silverado F(1). We suggest that ADH activity may play a role in chilling tolerance that is not related to maintenance of glycolysis and ATP production as has been observed during oxygen depravation.

Adenosine Triphosphatases↗
PubMed2002

Effectiveness of the MSC cold cap system in the prevention of chemotherapy-induced alopecia.

OBJECTIVE: To study the effectiveness of the MSC cold cap system to prevent chemotherapy-induced alopecia. METHODS: The system was applied in 83 cancer patients (mean age 49.8 years) undergoing chemotherapy with alopecia-causing agents. Seven patients did not tolerate the system. Seventy-six patients were evaluable for assessment; 26 received anthracycline (group A), 33 taxane (group T), 5 anthracycline plus taxane (group AT), 7 intravenous etoposide (group E) and 5 ifosfamide with or without other alopecia-causing drugs (group I). In group A, 18 patients received conventional (subgroup Ac) and 8 high doses (subgroup Ah). In group T, 8 patients received docetaxel (subgroup D) and 25 paclitaxel (subgroup P). Alopecia grade 0-1 (Dean's system) was considered as treatment success. RESULTS: Grade 0-1 alopecia was achieved in 49/76 (64.5%) patients: group T 23/33 (69.6%), subgroup P 16/25 (64%) and subgroup D 7/8 (87.5%); group A 18/26 (69.2%), subgroup Ac 16/18 (88.8%) and subgroup Ah 2/8 (25%); group AT 1/5 (20%); group E 6/7 (85.7%), and group I 1/5 (20%). CONCLUSIONS: The MSC cold cap system is effective in preventing alopecia from anthracycline, etoposide or taxane but not from anthracycline-taxane combinations or ifosfamide-containing regimens.

Adult↗
PubMed1987

[New pharmacologic developments in physical urticaria--therapeutic consequences].

Recent evidence suggests that mast cell derived mediators other than histamine are likely to be involved in the pathogenesis of physical urticarias. Much of the work has been performed in idiopathic cold contact urticaria where the presence of neutrophil and eosinophil chemotactic factors, and platelet activating factor-like lipid substances have been previously demonstrated. Now, an increase in prostaglandin D2 measured by GC-MS has been demonstrated in venous blood draining the cold challenged area. This appeared a few minutes later than histamine, but then both substances paralleled the onset, development and subsidence of the urticarial reaction. There appeared to be no quantitative relationship between histamine and PGD2 release. A similar rise in histamine and PGD2 occurred on heat challenge of a subject with the rare localized form of heat urticaria. This rise of both substances was considerably reduced after combined treatment with induction of tolerance and oral indomethacin. The concentrations of PGD2 measured suggested that it plays an indirect role.

Cold Temperature↗

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