Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “FRIGIDITY”

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 199 records · Page 11Linked to original sources

Sexual dysfunction in treated breast cancer patients.

BACKGROUND: This study examined the impact of breast cancer therapy on women's sexuality. PATIENTS AND METHODS: A questionnaire concerning various sexual problems experienced before and after treatment was anonymously completed by 50 women in the outpatient clinic of our hospital's Division of Radiation Oncology. To be eligible, subjects had to be disease-free and sexually active. They also had to have undergone surgery at least one year previously and have completed CT and or RT. Fifty-eight percent of the women involved had undergone mastectomy and 42% had undergone quadrantectomy followed by RT. RESULTS: Ninety percent of the subjects continued sexual activity after treatment, but there was an increase in the incidence of sexual problems which resulted in a slight reduction in the quality of their sex lives. Sixty-four percent of the women experienced an absence of sexual desire and 48% low sexual desire, while 38% had dyspareunia, 44% frigidity and 42% lubrication problems. Vaginismus, brief intercourse and female orgasmic disorder were reported by 30% of the subjects. Thirty-six percent suffered from sexual dysfunction before treatment, which worsened in about 27%, while in 49% of women sexual problems arose mainly after chemotherapy (26%) or surgery (12%). About one-half experienced changes in the relationship with their partner. CONCLUSION: Breast cancer patients experienced sexual dysfunction: ours found it easier to discuss the problems with their partner during their illness (62%) than with doctors and psychologists (15%).

Adult↗

Learning in mature mice (Peromyscus leucopus) subjected to deep hypothermia as neonates.

In certain species of nonhibernating rodents, although young nestlings cease breathing and heart action when their body temperature is lowered to near freezing, the nestlings need only be rewarmed to recover. This remarkable capacity for immediate recovery has been known many years, but long-range consequences of deep neonatal hypothermia have never before been investigated. Mice (Peromyscus leucopus) that had been exposed to four 2.5-hr episodes of deep (2-4 degrees C) hypothermia when 4-10 days old were later compared with littermate controls in their performance on two learning tasks. The two groups did not differ in their acquisition or extinction of a lithium-induced learned taste aversion to sucrose. Nor did they differ in learning to find a hidden platform in a swimming pool. Thus in a nonhibernating rodent species, deep hypothermia experienced neonatally--unlike similar hypothermia administered in adulthood--seems not to induce deficits in subsequent learning capabilities. The resistance of neonates to damage probably represents an adaptation, for their modest thermoregulatory abilities render them vulnerable to deep hypothermia in frigid environments.

Animals↗

High abundance of Archaea in Antarctic marine picoplankton.

Archaea (archaebacteria) constitute one of the three major evolutionary lineages of life on Earth. Previously these prokaryotes were thought to predominate in only a few unusual and disparate niches, characterized by hypersaline, extremely hot, or strictly anoxic conditions. Recently, novel (uncultivated) phylotypes of Archaea have been detected in coastal and subsurface marine waters, but their abundance, distribution, physiology and ecology remain largely undescribed. Here we report exceptionally high archaeal abundance in frigid marine surface waters of Antarctica. Pelagic Archaea constituted up to 34% of the prokaryotic biomass in coastal Antarctic surface waters, and they were also abundant in a variety of other cold, pelagic marine environments. Because they can make up a significant fraction of picoplankton biomass in the vast habitats encompassed by cold and deep marine waters, these pelagic Archaea represent an unexpectedly abundant component of the Earth's biota.

Animals↗

Protein flexibility acclimatizes photosynthetic energy conversion to the ambient temperature.

Adjustment of catalytic activity in response to diverse ambient temperatures is fundamental to life on Earth. A crucial example of this is photosynthesis, where solar energy is converted into electrochemical potential that drives oxygen and biomass generation at temperatures ranging from those of frigid Antarctica to those of scalding hot springs. The energy conversion proceeds by concerted mobilization of electrons and protons on photoexcitation of reaction centre protein complexes. Following physicochemical paradigms, the rates of imperative steps in this process were predicted to increase exponentially with rising temperatures, resulting in different yields of solar energy conversion at the distinct growth temperatures of photosynthetic mesophiles and extremophiles. In contrast, here we show a meticulous adjustment of energy conversion rate, resulting in similar yields from mesophiles and thermophiles. The key molecular players in the temperature adjustment process consist of a cluster of hitherto unrecognized protein cavities and an adjacent packing motif that jointly impart local flexibility crucial to the reaction centre proteins. Mutations within the packing motif of mesophiles that increase the bulkiness of the amino-acid side chains, and thus reduce the size of the cavities, promote thermophilic behaviour. This novel biomechanical mechanism accounts for the slowing of the catalytic reaction above physiological temperatures in contradiction to the classical Arrhenius paradigm. The mechanism provides new guidelines for manipulating the acclimatization of enzymes to the ambient temperatures of diverse habitats. More generally, it reveals novel protein elements that are of potential significance for modulating structure-activity relationships in membrane and globular proteins alike.

Acclimatization↗

Lack of interaction of hyperpnoea with methacholine and histamine in asthma.

1. The thermal precipitants of asthma (exercise and hyperventilation) appear to have a unique pathogenesis that does not alter bronchial responsiveness. In the present work, we tested whether hyperpnoea interacts with other constrictor stimuli.2. To provide data on this issue, we exposed 17 subjects with asthma to isocapnic hyperventilation of frigid air (HV), methacholine (METH) and histamine (HIS) alone and in combination.3. With HV (mean ventilation=55.6+/-7.7 litres/min), METH (2.20+/-0.7 mmol/l) and HIS (10.35+/-5.04 mmol/l) alone, the decrements in forced expiratory volume in 1 s (FEV1) from baseline were 27.4+/-3.4, 27.4+/-3.8 and 32.4+/-3% respectively (n=9). Giving the agonists simultaneously did not produce additive effects (Delta FEV1 HV+METH=32.8+/-3.6%; HV+HIS=28.7+/-5.1%). None of the individual or combined responses was significantly different from each other. Changing the sequence of the experiments and giving METH at the height of the HV-induced bronchial narrowing, instead of during hyperpnoea, did not alter the findings (n=8). The maximum fall in FEV1 after both bronchoconstrictors in this experiment (Delta FEV1=32.3+/-4.3%) was not significantly different from either alone (HV=22.8+/-1.0%; METH=27.3+/-1.9%). When METH and HIS were administered together, however (n=5), a positive interaction ensued (METH=1.53+/-0.56 mmol/l, Delta FEV1=15.6+/-4.6%; HIS=4.77+/-2.07 mmol/l, Delta FEV1=18. 8+/-3.1%; METH+HIS Delta FEV1=33.4+/-5.2%; P<0.001 compared with the individual effects).4. These results indicate that HV does not interact with stimuli that directly or indirectly modulate airway calibre. It is unclear if this effect represents protection conferred from increased bronchial blood flow or derives from differences in effector mechanisms between the thermal and pharmacological agonists.

Adult↗

Undiagnosed exercise-induced bronchoconstriction in ski-mountaineers.

Because the practise conditions put the ski-mountaineering athletes potentially at risk for exercise-induced bronchoconstriction (EIB), this study was conducted to estimate the prevalence of EIB in this population. Thirty-one highly-trained ski-mountaineers with racing experience participating in the race were evaluated. EIB was determined after a European race at high altitude and frigid conditions. Pre-race investigations included pulmonary function measurements and a questionnaire enquiring about i) training habits, ii) respiratory history during training and/or competition. Pulmonary function was also tested after the race. None of the athletes reported a basal airway obstruction. Two groups were determined after post-race airway response: i) EIB (+) group exhibiting a fall in FEV (1) > or = 10 % (n = 15) and ii) EIB (-) without fall in FEV (1) or fall < 10 % (n = 16). Neither training habits nor baseline lung function were associated with the post-race airway response. Six of the 31 ski-mountaineers had a previous physician-made diagnosis of asthma and/or EIB, nevertheless 23 of our athletes complained about at least one characteristic symptom of asthma during practise. Four of our 15 EIB (+) had a previous physician-made diagnosis of asthma/EIB indicating that 73 % of EIB (+) athletes were undiagnosed for EIB. The proportion of allergic athletes was not significantly different between EIB (+) and EIB (-). This study showed that approximatively half of highly-trained ski-mountaineers with racing experience can develop EIB after a race and that 73 % of them are unaware of the problem.

Adult↗

[Bromocriptine and tamoxifen--a new therapeutic approach in suppression-resistant prolactin-secreting adenomas].

In the present study the combination of tamoxifen and bromocriptine was tried for the suppression of prolactin in prolactin secreting adenomas which were resistant to suppression with bromoergocriptine alone. 10 women under treatment with 2.5-10 mg of parlodel (bromocriptine) for pituitary tumours of various sizes were additionally treated with tamoxifen 10-20 mg. (nolvadex) daily. Two patients had a previous incomplete resection for chromophobe adenomas. The other patients refused operation. Two women were also studied who did not tolerate a bromoergocriptine therapy because of side effects. In 6 of the 10 women with combination treatment a satisfactory suppression of the prolactin was observed. Four women were cleared of their amenorrhoea and galactorrhoea. One woman conceived. One woman lost her frigidity. Three women, among those the two with severe side effects from bromoergocriptine, tolerated the combined treatment well. Four women showed no success with the combined treatment. The effectiveness of the combined treatment was not correlated with the size of the tumour nor the clinical or biochemical baseline. The results lead to the conclusion that tamoxifen is capable of improving the suppression of prolactin or render the adenomas suppressible in a large number of cases.

Adolescent↗

Effect of long-term salmeterol treatment on exercise-induced asthma.

BACKGROUND: With long-term administration of salmeterol, the extent of protection afforded by the drug against experimental precipitants of asthma such as methacholine and adenosine may decrease. Whether this effect extends to a clinically relevant stimulus such as exercise is unknown. METHODS: We performed a random-order, double-blind, crossover trial in 20 patients with exercise-induced asthma. Each patient received inhaled salmeterol or placebo twice daily for a month, with a one-week washout period between treatments. The patients performed cycle ergometry while breathing frigid air 30 minutes after the morning dose and 9 hours later on the 1st, 14th, and 29th study days. The primary end point was the extent of the decrease in forced expiratory volume in 1 second (FEV1) 10 minutes after exertion. RESULTS: With placebo, significant airway narrowing developed at all times (mean [+/-SE] decrease from base line in FEV1, 19+/-2 percent in the morning and 18+/-2 percent in the evening). The morning dose of salmeterol attenuated the degree of bronchoconstriction at all times (decrease in FEV1 on day 1, 5+/-2 percent; on day 14, 10+/-3 percent; and on day 29, 9+/-3 percent; P=0.10). Its ability to act throughout the day, however, decreased with long-term administration (decrease in FEV1 from morning to evening on day 1, 6+/-2 percent; on day 14, 15+/-3 percent; and on day 29, 14+/-3 percent; P=0.003). CONCLUSIONS: Protection against exercise-induced asthma is maintained with long-term administration of salmeterol, but the length of time that the drug remains active after a single dose decreases.

Adrenergic beta-Agonists↗

Comparative effects of long-acting beta2-agonists, leukotriene receptor antagonists, and a 5-lipoxygenase inhibitor on exercise-induced asthma.

BACKGROUND: Exercise-induced asthma (EIA) is a common problem that can be controlled with long-acting beta-agonists and leukotriene-modifying compounds. There is, however, limited information on the comparative effectiveness of the two classes of drugs, as well as the relative potencies of the antileukotriene agents. OBJECTIVE: The purpose of the present study was to provide data on the above issues. METHODS: We performed a random-order, blinded, double-dummy, placebo-controlled trial in 10 patients with EIA. Each subject received standard single doses of salmeterol, montelukast, zafirlukast, zileuton, and placebo on separate days. The participants performed 4 minutes of cycle ergometry while breathing frigid air 1, 4, 8, and 12 hours after administration of the test agents. The primary endpoint was the extent of the decrement in the FEV(1) 10 minutes after exertion. RESULTS: With placebo, symptomatic airway narrowing developed at all times (mean +/- SE decrease in FEV(1) ranged between 21% +/- 5% and 26% +/- 5%). Salmeterol acted quickly and significantly blunted the obstructive response for 12 hours (DeltaFEV(1) first hour: 8% +/- 3%; DeltaFEV(1) twelfth hour: 8% +/- 3%; P <.0001 vs placebo and P =.72 vs time). The leukotriene-modifying agents produced effects within 1 hour of ingestion. Like salmeterol, montelukast and zafirlukast also offered long-lasting protection, and there were no significant differences between them (montelukast DeltaFEV(1) twelfth hour: 9% +/- 4%; zafirlukast DeltaFEV(1) twelfth hour: 11% +/- 2%; P =.75) or the beta(2)-agonist (montelukast vs salmeterol: P =.72; zafirlukast vs salmeterol: P =.48). Zileuton provided equivalent prophylaxis for the first 4 hours (DeltaFEV(1) fourth hour: 11% +/- 2%); however, by 8 hours, it was less efficacious than all of the other active compounds, and by 12 hours it did not differ from placebo (DeltaFEV(1) twelfth hour: 19% +/- 4%; P =.33). CONCLUSIONS: Single doses of the currently available leukotriene receptor antagonists provide prompt effective and persistent defense against EIA that equals that seen with a long-acting beta(2)-agonist. The synthesis inhibitor zileuton affords a comparable magnitude of prophylaxis but has a considerably shorter duration of action.

Adrenergic beta-Agonists↗

Sexual dysfunction among infertile Nigerian women.

The sexual histories of 97 infertile women were collected using questionnaires. Sexual dysfunction was found to be common among them, particularly frigidity (78.4%), dyspaereunia (57.7%), difficulty with sexual arousal (20.6%) and difficulty in achieving orgasm (20.6%). These could affect sexual acceptance and subsequently coital frequency, thus complicating their infertility problem further. Hence, there is the need of addressing these issues when managing these patients.

Female↗

Functional antifreeze glycoprotein genes in temperate-water New Zealand nototheniid fish infer an Antarctic evolutionary origin.

The fish fauna of the Antarctic Ocean is dominated by five endemic families of the Perciform suborder Notothenioidei, thought to have arisen in situ within the Antarctic through adaptive radiation of an ancestral stock that evolved antifreeze glycoproteins (AFGPs) enabling survival as the ocean chilled to subzero temperatures. The endemism results from geographic confinement imposed by a massive oceanographic barrier, the Antarctic Circumpolar Current, which also thermally isolated Antarctica over geologic time, leading to its current frigid condition. Despite this voluminous barrier to fish dispersal, a number of species from the Antarctic family Nototheniidae now inhabit the nonfreezing cool temperate coasts of the southern continents. The origin of these temperate-water nototheniids is not completely understood. Since the AFGP gene apparently evolved only once, before the Antarctic notothenioid radiation, the presence of AFGP genes in extant temperate-water nototheniids can be used to infer an Antarctic evolutionary origin. Genomic Southern analysis, PCR amplification of AFGP genes, and sequencing showed that Notothenia angustata and Notothenia microlepidota endemic to southern New Zealand have two to three AFGP genes, structurally the same as those of the Antarctic nototheniids. At least one of these genes is still functional, as AFGP cDNAs were obtained and low levels of mature AFGPs were detected in the blood. A phylogenetic tree based on complete ND2 coding sequences showed monophyly of these two New Zealand nototheniids and their inclusion in the monophyletic Nototheniidae consisted of mostly AFGP-bearing taxa. These analyses support an Antarctic ancestry for the New Zealand nototheniids. A divergence time of approximately 11 Myr was estimated for the two New Zealand nototheniids, approximating the upper Miocene northern advance of the Antarctic Convergence over New Zealand, which might have served as the vicariant event that lead to the northward dispersal of their most recent common ancestor. Similar secondary northward dispersal likely applies to the South American nototheniid Paranotothenia magellanica, which has four AFGP genes in its DNA, but not to the sympatric nototheniid Patagonotothen tessellata, which does not appear to have any AFGP sequences in its genome at all.

Amino Acid Sequence↗

The sexually exploited child.

Sexual exploitation of children (under 14 years of age) is a common occurrence, although actual numbers are unknown. There are three major forms of sexual abuse: (1) incest, ie, sexual activity between consanguineous family members; (2) sexual assault, such as rape or molestation by adults not related to the child; and (3) habitual sexual exploitation for purposes of financial reward or perverse sexual satisfaction. Brother-sister incest has the highest incidence in the middle and upper socioeconomic levels and is probably the least damaging, psychologically, to sexual adjustment later in life. Father-daughter incest is more common in the lower socioeconomic levels and is thought to produce major disorders in the psychosexual area. Sexual assault of children, if handled supportively and with understanding by the surrounding adults, including parents, physicians, teachers, law enforcement officers, and others, can result in minimal sequelae; however, often the situation is handled with emotional reactions ranging from disgust to hysteria which result in the child's being victimized and traumatized unnecessarily. These latter situations lead to sexual acting-out in adolescence, promiscuity, perversions, or frigidity in adult sexual life. Teachers, physicians, and child welfare workers need to be attuned to the possibility to sexual abuse in the children they serve.

Adaptation, Psychological↗

Nitrogen use and carbon sequestered by corn rotations in the northern corn belt, U.S.

Diversified crop rotation may improve production efficiency, reduce fertilizer nitrogen (N) requirements for corn (Zea mays L.), and increase soil carbon (C) storage. Objectives were to determine effect of rotation and fertilizer N on soil C sequestration and N use. An experiment was started in 1990 on a Barnes clay loam (U.S. soil taxonomy: fine-loamy, mixed, superactive, frigid Calcic Hapludoll) near Brookings, SD. Tillage systems for corn-soybean ( Glycine max [L.] Merr.) rotations were conventional tillage (CS) and ridge tillage (CSr). Rotations under conventional tillage were continuous corn (CC), and a 4-year rotation of corn-soybean-wheat ( Triticum aestivum L.) companion-seeded with alfalfa ( Medicago sativa L.)-alfalfa hay (CSWA). Additional treatments included plots of perennial warm season, cool season, and mixtures of warm and cool season grasses. N treatments for corn were corn fertilized for a grain yield of 8.5 Mg ha(-1) (highN), of 5.3 Mg ha(-1) (midN), and with no N fertilizer (noN). Total (1990-2000) corn grain yield was not different among rotations at 80.8 Mg ha(-1) under highN. Corn yield differences among rotations increased with decreased fertilizer N. Total (1990-2000) corn yields with noN fertilizer were 69 Mg ha-1 under CSWA, 53 Mg ha(-1) under CS, and 35 Mg ha(-1) under CC. Total N attributed to rotations (noN treatments) was 0.68 Mg ha(-1) under CSWA, 0.61 Mg ha(-1) under CS, and 0.28 Mg ha(-1) under CC. Plant carbon return depended on rotation and N. In the past 10 years, total C returned from above- ground biomass was 29.8 Mg ha(-1) under CC with highN, and 12.8 Mg ha(-1) under CSWA with noN. Soil C in the top 15 cm significantly increased (0.7 g kg(-1)) with perennial grass cover, remained unchanged under CSr, and decreased (1.7 g kg(-1)) under CC, CS, and CSWA. C to N ratio significantly narrowed (-0.75) with CSWA and widened (0.72) under grass. Diversified rotations have potential to increase N use efficiency and reduce fertilizer N input for corn. However, within a corn production system using conventional tillage and producing (averaged across rotation and N treatment) about 6.2-Mg ha(-1) corn grain per year, we found no gain in soil C after 10 years regardless of rotation.

Agriculture↗

A wetter, younger Mars emerging.

Most researchers have believed that the days were long gone when water splashed on the surface of Mars or even near it. Now continuing analyses of martian meteorites and stunning images from the Mars Global Surveyor (MGS), which has been in orbit since 1997, are breathing new life into the Red Planet. Last month's announcement that the camera aboard MGS had spied signs of geologically recent--possibly even ongoing--water seeps has caught everyone's attention. Other, perhaps more persuasive, signs also suggest that water may even now flow on or beneath the frigid surface.

Exobiology↗

A pharmacologically distinct cyclic AMP receptor is responsible for the regulation of gp80 expression in Dictyostelium discoideum.

The EDTA-resistant cell-cell adhesion expressed at the aggregation stage of Dictyostelium discoideum is mediated by a cell surface glycoprotein of Mr 80,000 (gp80). The expression of gp80 is developmentally regulated by cyclic AMP (cAMP). In vitro nuclear run-on experiments show that transcription of the gp80 gene is initiated soon after the onset of development. The basal level of gp80 transcription is significantly augmented by exogenous cAMP pulses. Interestingly, in analog studies, 2'-deoxy-cAMP, 8-bromo-cAMP, and N6-monobutyryl-cAMP are all capable of inducing a rapid accumulation of gp80 mRNA, suggesting the presence of a unique cAMP receptor that responds equally well to these analogs. To determine whether intracellular cAMP plays a role in the regulation of gp80 expression, caffeine was used to block cAMP-induced receptor-mediated adenylate cyclase activation. Expression of gp80 mRNA was blocked in caffeine-treated cells but could be substantially restored by treatment with exogenous cAMP pulses, suggesting that adenylate cyclase activation is not required. gp80 expression was also examined in the signal transduction mutants synag 7 and frigid A. In both mutants, gp80 was expressed at the basal level. Pulses of cAMP as well as 2'-deoxy-cAMP and N6-monobutyryl-cAMP were capable of restoring the normal level of gp80 expression in synag 7 cells. These results, taken together, indicate bimodal regulation of gp80 expression during development and the involvement of a novel cAMP receptor in the transmembrane signalling pathway that regulates gp80 gene expression.

Cell Adhesion Molecules↗

Effects of inhaled sympathomimetics on obstructive response to respiratory heat loss.

To investigate the influence of inhaled sympathomimetics on the obstructive response to airway cooling, we had six asymptomatic atopic asthmatics perform eucapnic hyperventilation with frigid air at various levels of ventilation after pretreatment with aerosols of metaproterenol or placebo in a random blind fashion. In control experiments, eucapnic hyperventilation produced a progressive decrease in 1-s forced expiratory volume in a stimulus-response fashion as the level of ventilation rose in successive challenges. Metaproterenol did not produce an all-or-none blockade, but rather a parallel shift in the stimulus-response curve so that its protective effects could be overcome by increasing the stimulus. There was no effect on respiratory heat loss. These results explain, in a quantitative fashion, why a treatment schedule that permits a person with asthma to perform a given exercise task without difficulty becomes ineffective as the thermal burden or severity of the task increases.

Adult↗

Thermal mapping of the airways in humans.

To characterize the intrathoracic thermal events that occur during breathing in humans, we developed a flexible probe (OD 1.4 mm) containing multiple thermistors evenly spaced over 30.2 cm, that could be inserted into the tracheobronchial tree with a fiberoptic bronchoscope. With this device we simultaneously recorded the airstream temperature at six points from the trachea to beyond the subsegmental bronchi in six normal subjects while they breathed ambient and frigid air at multiple levels of ventilation (VE). During quiet breathing of room air the average temperature ranged from 32.0 +/- 0.05 degrees C in the upper trachea to 35.5 +/- 0.3 degrees C in the subsegmental bronchi. As ventilation was increased, the temperature along the airways progressively decreased, and at a VE of 100+ 1/min the temperature at the above two sites fell to 29.2 +/- 0.5 and 33.9 +/- 0.8 degrees C, respectively. Interval points were intermediate between these extremes. With cold air, the changes were considerably more profound. During quiet breathing, local temperatures approximated those recorded in the maximum VE room-air trial, and at maximum VE, the temperatures in the proximal and distal airways were 20.5 +/- 0.6 and 31.6 +/- 1.2 degrees C, respectively. During expiration, the temperature along the airways progressively decreased as the air flowed from the periphery of the lung to the mouth: the more the cooling during inspiration, the lower the temperature during expiration. These data demonstrate that in the course of conditioning inspired air the intrathoracic and intrapulmonic airways undergo profound thermal changes that extend well into the periphery of the lung.

Adult↗

Cold-induced bronchoconstriction: role of cutaneous reflexes vs. direct airway effects.

To determine the relative contributions of direct airway vs. reflex cutaneous thermal receptor stimulation in cold-induced bronchoconstriction, we isolated these two aspects of cold exposure in 10 asthmatics and 13 normal subjects. Ice packs were applied to the skin of the face, chest, thigh, and upper arm in random sequence while serially measuring specific conductance. In this fashion a limited mapping of skin-mediated bronchoconstriction was established. Warm packs were applied to the same areas of control for any potential nonspecific stimulatory effects. Cooling the skin induced bronchoconstriction to a similar degree in both groups; this effect was very small, did not induce symptoms, and was only seen with stimulation of the face. At another time, the subjects performed isocapnic hyperventilation of frigid air to ascertain their response to direct airway cooling. A moderate but significant correlation existed between skin and airway sensitivity; however, the magnitude of the two responses differed markedly. Breathing cold air at rest had no effect on lung function; however, elevating ventilation promptly produced bronchial narrowing. Hence, in a cold environment, the most potent stimulus for the development of airway obstruction in asthmatics derives from a direct airway effect.

Adult↗