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[Sequential observation on the influence of artificial wind-cold environment to immunologic function of mononuclear phagocytic system in mice].

According to TCM theory of Six Evils, the Wind-Cold is one of the pathogen. In order to find the mechanism of Wind-Cold in causing disease, the effect of subacute Wind-Cold stimulation on the phagocyte immunization in mice was observed. Results showed that through exposing in the Wind-Cold environment, the reticuloendothelial system (RES) clearance function and the hydrogen-peroxide releasing of peritoneal macrophage were suppressed. Sequential observation showed that the peak of immunosuppression occurred on the 3rd day after stimulation and began to normalize at 5th day. These results suggested that Wind-Cold stimulation could inhibit temporary phagocytosis of macrophage and bacteriocidal effect. Action of immunosuppression was believed to be produced by the increase of stress hormone after stimulation. Results also suggested that the pathogenic action of Wind-Cold on disease is somewhat related with the suppression of nonspecific cellular immunity.

Animals↗

Combined antiviral and antimediator treatment of rhinovirus colds.

An antiviral agent and two antiinflammatory compounds were used in a blinded, placebo-controlled study to treat experimental rhinovirus colds. Intranasal interferon-alpha 2b and ipratropium and oral naproxen were begun 24 h after rhinovirus inoculation. Treatment was continued three times a day for 4 days. Viral shedding (mean +/- SE) was 4.4 +/- 0.3 days for controls and 2.9 +/- 0.3 days for treated volunteers (P less than .003). Geometric mean virus titers were reduced in the treated group on all days (P = .02-.06). Serum antibody responses and postinfection geometric mean antibody titers were similar in both groups (P greater than .1). Colds developed in 6 of 16 treated and 7 of 8 control subjects (P = .05). Mean total symptom scores (P = .055), rhinorrhea (P less than .01), cough (P less than .01), and malaise (P less than .001) were reduced in treated subjects. Trends in reduction of nasal obstruction and sore throat also favored the treated group. Nasal secretion weights were 12.9 +/- 4.8 g in treated and 20.3 +/- 5.4 g in control subjects (P = .4). Medications were was tolerated.

Adult↗

[Whole-body cryotherapy in rehabilitation of patients with rheumatoid diseases--pilot study].

UNLABELLED: Cryotherapy as a whole-body cold therapy (with cold air cooled by addition of nitrogen blown on the patients in an open cabin) for treatment of inflammatory rheumatic diseases already started in Bad Säckingen in 1986. In 1996, a new cold chamber (this time a closed chamber without any addition of nitrogen) based on compressor technology was introduced. The aim of our study was to test whether significant pain relief could be achieved by means of this cold therapy. Furthermore, we were interested in the practicability and acceptance of this new technique. Wellbeing during the treatment application and pain level were assessed using verbal and numerical rating scales. The sample consisted of 120 consecutive patients (75% women, age: 30-67 yrs, M = 52.6 yrs). These patients were suffering from primary fibromyalgia (40.7%), rheumatoid arthritis (17.3%), chronic low back pain (16.4%), ankylosing spondylitis (10.9%), osteoarthritis (9.1%), secondary fibromyalgia (3.6%) and other autoimmune diseases (1.8%) (mean duration of symptoms: 4 yrs). The patients were treated 2.5 minutes on average in the main chamber (mean temperature: -105 degrees C). The patients' statements concerning their pain level were analyzed by means of analyses of variance with repeated measures and paired-sample t-tests. RESULTS: The pain level after application of the cold therapy decreases significantly. The pain reduction lasts about 90 minutes. The initial pain level decreases during the whole time of treatment, no significant improvement, though, can be shown from the middle to the end of the four-weeks treatment. According to the results of our study, there is evidence that the whole-body cold therapy generates important short-term effects and somewhat weaker effects over the treatment period as a whole. Short-term pain reduction facilitates intensive application of physiotherapy and Occupational Therapy. The treatment procedure is practicable, and all in all well tolerated. From the patients' point of view, whole-body cold therapy is an essential part of the rehabilitation programme.

Adult↗

Altering gender role expectations: effects on pain tolerance, pain threshold, and pain ratings.

The literature demonstrating sex differences in pain is sizable. Most explanations for these differences have focused on biologic mechanisms, and only a few studies have examined social learning. The purpose of this study was to examine the contribution of gender-role stereotypes to sex differences in pain. This study used experimental manipulation of gender-role expectations for men and women. One hundred twenty students participated in the cold pressor task. Before the pain task, participants were given 1 of 3 instructional sets: no expectation, 30-second performance expectation, or a 90-second performance expectation. Pain ratings, threshold, and tolerance were recorded. Significant sex differences in the "no expectation" condition for pain tolerance (t = 2.32, df = 38, P <.05) and post-cold pressor pain ratings (t = 2.6, df = 37, P <.05) were found. Women had briefer tolerance times and higher post-cold pressor ratings than men. When given gender-specific tolerance expectations, men and women did not differ in their pain tolerance, pain threshold, or pain ratings. This is the first empirical study to show that manipulation of expectations alters sex differences in laboratory pain.

Adult↗

Transformation of tobacco with a gene for the thermophilic acyl-lipid desaturase enhances the chilling tolerance of plants.

The desC gene for the acyl-lipid Delta9-desaturase from the thermophilic cyanobacterium Synechococcus vulcanus was introduced into Nicotiana tabacum under control of the 35S promoter. Expression of the desaturase was confirmed by Western blotting. Lipid analysis revealed that lipid content and the extent of fatty acid unsaturation significantly increased in leaves of transgenic plants. Chilling tolerance of those plants also increased, as estimated by the electrolyte leakage from the tissues damaged by cold treatments. Seeds of plants that expressed the desC gene imbibed at low temperatures demonstrated higher chilling tolerance than those of the control plants. The results demonstrate that the cyanobacterial thermophilic acyl-lipid desaturase was efficiently expressed in tobacco at ambient temperatures, and its expression resulted in the enhanced chilling tolerance of the transgenic plants.

Acclimatization↗

Perception and gut reflexes induced by stimulation of gastrointestinal thermoreceptors in humans.

1. Experimental studies in animals suggest the existence of thermoreceptors in the gastrointestinal tract. Our aim was to investigate the distribution and specificity of upper gut thermoreceptors in humans. 2. In healthy subjects, thermal stimulation of the stomach (n = 8) and the small intestine (n = 6) was produced by means of a thermostat, which recirculates water at adjusted temperatures through an ultrathin intraluminal bag. Progressively warm (42, 47 and 52 degrees C) and cold (32, 22 and 12 degrees C) stimuli of 3 min duration were alternately applied at 13 min intervals. Perception was scored on a scale of 0-6 and gastric tone responses were measured with a barostat. 3. Thermal stimuli induced specific responses: cold stimuli induced abdominal cold sensation and a reflex contraction of the stomach, whereas warm stimuli induced warm sensation and a reflex gastric relaxation. 4. Thermal stimuli induced similar stimulus-related perception in the stomach and small intestine (temperatures between 12 and 49.5 +/- 0.5 degrees C were tolerated). 5. The reflex responses were site specific. Warm and cold stimulation of the stomach induced gastric reflexes (76 +/- 26 ml isobaric expansion at 47 degrees C, and 68 +/- 10 ml contraction at 12 degrees C; P < 0.05 for both). However, only warm, not cold, stimulation of the intestine induced enterogastric reflexes. 6. These results indicate that in humans, warm and cold receptors are distributed along the gastrointestinal tract and project afferent input both into perception and reflex circuits with specific topographic organization.

Adult↗

Thymic epithelium and the induction of transplantation tolerance in nude mice.

Immunological tolerance of self has been studied experimentally by the induction of unresponsiveness to antigens of the major histocompatibility complex (MHC) in neonatal mice. The specific unresponsiveness resulting from such neonatal tolerance induction is first demonstrable in the thymus, suggesting that neonatal tolerance is induced by some cellular component of the thymus, or at some prethymic stage. Recent transplantation studies suggest that thymic epithelium, derived by organ culturing fetal mouse thymus in the presence of deoxyguanosine, survives in an allogeneic host environment despite the continued expression of MHC donor antigens, but fails to induce allotolerance. We demonstrate here that embryonic thymus lobes organ cultured at 24 degrees C, a treatment that deletes the lymphohaematopoietic component of thymus leaving the epithelial matrix intact, when transplanted to intact histoincompatible recipients, similarly survive for a prolonged period and do not induce tolerance to donor MHC antigens. However, when such culture-derived thymic epithelium is allografted to athymic nude mice, host-derived lymphocytes from both the epithelial graft and recipient spleen are unresponsive to the MHC antigens of the epithelial donor. The results suggest that, when investigated in a system which precludes the possible involvement of extrinsic mature T cells, processed by the syngeneic host thymus, thymic epithelium may induce transplantation tolerance.

Animals↗

Rapid responses to high temperature and desiccation but not to low temperature in the freeze tolerant sub-Antarctic caterpillar Pringleophaga marioni (Lepidoptera, Tineidae).

A broad definition of rapid cold hardening (RCH) is that it is the process whereby insects increase their survival of a sub-zero temperature after a brief (h) pre-exposure to a less severe low temperature. The effects of various pre-treatments on survival of two h at -7.9 degrees C were investigated in the freeze tolerant sub-Antarctic caterpillar Pringleophaga marioni (Lepidoptera: Tineidae), the first time RCH has been investigated in a freeze tolerant arthropod. All caterpillars froze when exposed to -7.9 degrees C, and none of the low temperature pre-treatments (-5, 0, 5 and 15 degrees C, as well as -5 degrees C and 0 degrees C with a delay before freezing) nor slow cooling (0.1 degrees C/min) elicited any improvement in survival of -7.9 degrees C as compared to controls. However, high temperature treatments (25, 30 and 35 degrees C), desiccation and acclimation for 5 days at 0 degrees C did result in significant increases in survival of the test temperature, possibly as a result of heat shock protein production. Haemolymph osmolality was elevated only by the 35 degrees C pre-treatment. It is suggested that the unpredictable environment of Marion Island means that P. marioni must always be physiologically prepared to survive cold snaps, and that this year-round cold hardiness therefore supersedes a rapid cold hardening response.

Acclimatization↗

Effects of exercise in cool water on body weight loss.

Seven obese women (greater than 30 per cent body fat, mean = 43 per cent) performed moderate exercise (30 to 40 per cent of maximal oxygen consumption) for 90 min during head-out immersion in cool water (17 to 22 degrees C) five times per week for eight weeks to determine if cold exposure and the attendant caloric deficit in body heat stores would lead to body weight loss. Exercise was on a cycle ergometer that was modified for underwater use. Body weight, body fat, fat-free body weight, and caloric intake did not change significantly as a result of the exercise program in cool water. The significant heat debts incurred were presumably repaid without an increase in energy expenditure. The caloric balance and the thermal data obtained suggest that body heat stores were slowly repaid during recovery by resting metabolic heat production associated with a reduced rate of body heat loss. Maximal oxygen uptake did not increase significantly. No metabolic or thermal evidence was found to support cold adaptation in the obese women. Ergometer exercise in water as well-tolerated, as evidenced by no exercise-related injuries and an adherence rate of 93 per cent. It was concluded that, while cold exposure does not increase caloric expenditure significantly in obese individuals, exercising regularly in cool water may be beneficial as it may motivate obese people to exercise at higher intensity for thermal comfort and the water environment may help prevent injuries.

Adipose Tissue↗

Hsp104 is required for tolerance to many forms of stress.

Heat-shock proteins (hsps) are induced by many types of stress. In Saccharomyces cerevisiae, a mutation in the HSP104 gene, a member of the highly conserved hsp100 gene family, reduces the ability of log-phase fermenting cells to withstand high temperatures after mild, conditioning pretreatments. Here, we examine the expression of hsp104 and its importance for survival under many different conditions. Hsp104 is expressed at a higher level in respiring cells than in fermenting cells and is required for the unusually high basal thermotolerance of respiring cells. Its expression in stationary phase cells and spores is crucial for the naturally high thermotolerance of these cell types and for their long-term viability at low temperatures. The protein is of critical importance in tolerance to ethanol and of moderate importance in tolerance to sodium arsenite. Thus, the hsp104 mutation establishes the validity of a long-standing hypothesis in the heat-shock field, namely, that hsps have broadly protective functions. Further, that a single protein is responsible for tolerance to heat, ethanol, arsenite and long-term storage in the cold indicates that the underlying causes of lethality are similar in an extraordinary variety of circumstances. Finally, the protein is of little or no importance in tolerance to copper and cadmium, suggesting that the lethal lesions produced by these agents are fundamentally different from those produced by heat.

Cadmium↗

Isolation of mutations affecting the development of freezing tolerance in Arabidopsis thaliana (L.) Heynh.

We screened for mutations deleterious to the freezing tolerance of Arabidopsis thaliana (L.) Heynh. ecotype Columbia. Tolerance was assayed by the vigor and regrowth of intact plants after cold acclimation and freezing. From a chemically mutagenized population, we obtained 13 lines of mutants with highly penetrant phenotypes. In 5 of these, freezing sensitivity was attributable to chilling injury sustained during cold acclimation, but in the remaining 8 lines, the absence of injury prior to freezing suggested that they were affected specifically in the development of freezing tolerance. In backcrosses, freezing sensitivity from each line segregated as a single nuclear mutation. Complementation tests indicated that the 8 lines contained mutations in 7 different genes. The mutants' freezing sensitivity was also detectable in the leakage of electrolytes from frozen leaves. However, 1 mutant line that displayed a strong phenotype at the whole-plant level showed a relatively weak phenotype by the electrolyte leakage assay.

Adaptation, Physiological↗

Evaluation of oral terfenadine for treatment of the common cold.

This study was a single center trial comparing the effects of the nonsedating antihistamine terfenadine, at a dose of 120 mg twice a day, with placebo in the treatment of rhinitis symptoms associated with the common cold. Forty-nine subjects were treated with terfenadine, 120 mg twice each day, and 48 subjects were treated with placebo twice each day for four or five days. Evaluations by both subjects and physicians suggest that terfenadine at 120 mg given twice daily marginally improved sneezing and total symptom scores at day 4. When comparing terfenadine to placebo, neither the symptoms nor signs of the common cold improved in a clinically or statistically significant manner. Terfenadine was well tolerated and had a low incidence of side effects. Terfenadine was found to be ineffective in the treatment of the signs and symptoms of the common cold.

Administration, Oral↗

Efficacy and safety of oral pleconaril for treatment of colds due to picornaviruses in adults: results of 2 double-blind, randomized, placebo-controlled trials.

The novel capsid-binding antiviral pleconaril inhibits in vitro replication of most rhinoviruses and enteroviruses. Oral pleconaril treatment was studied in 2 parallel randomized, double-blind, placebo-controlled trials. Among 1363 picornavirus-infected participants (65%) in the studies combined, the median time to alleviation of illness was 1 day shorter for pleconaril recipients than for placebo recipients (P<.001). Cold symptom scores and frequency of picornavirus cultured from nasal mucus specimens were lower among pleconaril recipients by day 2 of treatment. No treatment effects were seen in those without picornavirus infection. Pleconaril was associated with a higher incidence of nausea (6% vs. 4%) and diarrhea (9% vs. 7%) and with small increases in mean serum cholesterol levels and platelet counts, compared with baseline measurements. A subsequent 6-week prophylaxis study found that pleconaril induces cytochrome P-450 3A enzymes, which metabolize a variety of drugs, including ethinyl estradiol. Early pleconaril treatment was well tolerated and significantly reduced the duration and severity of colds due to picornaviruses in adults.

Administration, Oral↗

Active oxygen detoxifying enzymes and phenylalanine ammonia-lyase in the ethylene-induced chilling tolerance in citrus fruit.

The effects of applying ethylene (2 microL x L(-)(1)) during cold storage of Fortune mandarins on the development of chilling-induced peel damage and on changes in the activities of the enzymes of the antioxidant system, superoxide dismutase, catalase (CAT), ascorbate peroxidase, guaiacol peroxidase, and glutathione reductase, and on phenylalanine ammonia-lyase (PAL) have been investigated. Chilling damage was reduced by applying ethylene during fruit storage at 1.5 degrees C. PAL activity increased in response to cold stress and was higher in fruit held under ethylene than under air during the whole storage period, whereas CAT was temporarily higher in ethylene-treated fruit. In contrast, the activities of the other enzymes were not increased by ethylene. The global results suggest that the ethylene-induced chilling tolerance in Fortune mandarins might be due to increased PAL and CAT activities.

Ascorbate Peroxidases↗

Cognitive control of pain: four serendipitous results.

The experiment was designed to determine whether specific cognitive strategies are effective in reducing pain. Subjects were tested either on cold pain or pressure pain. Although the cognitive strategies did not significantly alter pain tolerance or pain intensity, the following four findings emerged: (a) males and females responded in a similar manner to the painful stimuli, (b) both the experimental subjects and the controls had surprisingly high tolerance of pain, (c) subjects typically generated their own thoughts and images to control pain, and (d) subjects responded to cold pain and to pressure pain in a similar manner.

Cognition↗

[Characteristics of Yunnan Province rice landrace core collections under phosphorus deficiency].

Soil phosphorus (P) deficiency is a major yield-limiting factor in rice production. Employing 526 rice landrace accessions from 5 rice-planting regions and 16 prefectures in Yunnan Province, this paper studied their P-deficiency tolerance characteristics by comparing the relative plant dry weight under acid red soil condition. The results showed that Northwest Yunnan cold highland japonica rice-planting region was most abundant in P-deficiency tolerance core collection of indica, and there was no significant difference in japonica among five ecological zones of rice landraces. Nujiang, Lijiang, Dehong, Wenshan, Xishuangbana and Yuxi were most abundant in P-deficiency tolerance core collection of indica, and Lijiang, Wenshan and Chuxiong were most abundant in P-deficiency tolerance core collection of japonica. Indica had a higher P-deficiency tolerance than japonica. The P-deficiency tolerance of rice was significantly related with its genetic diversity, rice breeding and acid red soils.

Breeding↗

Obviation of opioid withdrawal syndrome by concomitant administration of naltrexone in microgram doses: two psychonautic bioassays.

Two psychonautic bioassays (self-experiments) in stepwise and abrupt cessation of long-term daily oral ingestion habits of 800 mg of codeine phosphate are presented. Concomitant administration of minute doses (about 0.5 mcg) of the opioid antagonist naltrexone with each dose of codeine was found in both cases to obviate the expected opioid withdrawal syndrome, resulting in asymptomatic and uneventful transitions from physical opioid dependency states to exogenous opioid-free metabolism. These experiments are analyzed in the context of a conjectured, rapid, iterative reduction and complete elimination of opioid tolerance, once acquired. It was found that coadministration of naltrexone with codeine phosphate obviated the development of both tolerance and physical dependency over several months of four daily oral doses of 200 mg, allowing abrupt ("cold turkey"), asymptomatic and uneventful withdrawal. This points the way to the biochemical substrate of opioid tolerance itself, and shows that this can easily and inexpensively be blocked, even over months of iterative oral administration of substantial doses of opioid analgesics. Finally, it suggests the opioid withdrawal syndrome is directly related to the physiology of opioid tolerance, and can be prevented by blocking tolerance itself. Even when tolerance has been acquired, this can be reduced stepwise over a matter of days, with no symptoms of opioid withdrawal syndrome.

Codeine↗

An open-label, single-center, phase IV clinical study of the effectiveness of zinc gluconate glycine lozenges (Cold-Eeze) in reducing the duration and symptoms of the common cold in school-aged subjects.

Each year, more than 62 million cases of the common cold in the United States require medical attention and more than 80% affect school-aged children. The objective of this prospective, intent-to-treat, phase IV study was to determine the therapeutic and prophylactic effectiveness of zinc gluconate glycine lozenges (Cold-Eeze) for the common cold. Zinc lozenges were administered once daily during the cold season for prophylaxis. For therapeutic purposes, lozenges were given 4 times per day. The primary objective of the study was the treatment effect on cold duration, and the secondary objective was the effect on the number of common colds. A putative control from our previous study was used for comparison. A total of 178 children, ages 12 to 18 years, was enrolled, of which 134 met criteria for efficacy analysis. The average cold duration with therapeutic lozenge use was 6.9 +/- 3.1 days, significantly shorter than the 9.0 +/- 3.5 days found in the control group (P < 0.001). The mean number of colds was 1.28 +/- 1.03 with zinc lozenge prophylaxis versus 1.7 +/- 1.91 without prophylaxis (P < 0.05), a 25% reduction. With prophylaxis, 25% of the subjects did not experience a cold and two-thirds never had a cold or only had 1 cold. There was no antibiotic use for any cold, and there were no adverse events reported. Results of this study are consistent with those from our previous retrospective study showing significantly shorter cold duration and fewer colds with the use of zinc gluconate glycine lozenges. The zinc gluconate glycine lozenges are well tolerated and are an easy-to-administer therapy that has the potential to substantially reduce cold-related school absences and antibiotic use and misuse as well as to provide a cost saving.

Adolescent↗