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61.
A whole body plethysmograph (body box) equipped with a flow meter (see Figure 1) was used for objective quantification of the effects of single doses of clemastine fumarate 2.68 mg, chlorpheniramine 4 mg and placebo in a double-blind study of 48 patients with seasonal allergic rhinitis. This technique offers an objective means of assessing drug effects on nasal congestion and obstruction. Before the development of whole body plethysmography, only subjective assessments of antihistamines' effects on nasal blockage or congestion were available. These subjective reports usually noted that nasal blockage or congestion was refractory to antihistamines or minimally relieved by them. However, in this study, nasal and oral airway resistances, each measured by whole body plethysmography, were lowered by clemastine fumarate and chlorpheniramine. These results were corroborated by the patients' and physician's assessments of changes in symptom severity and the physician's evaluation of intranasal photographs taken for each patient. Oral airway resistance of patients treated with clemastine fumarate was improved to a significantly greater extent than in patients receiving placebo. At two hours post-drug, patients receiving clemastine fumarate usually showed a greater response in most assessments than those receiving chlorpheniramine, and the trend of most comparisons was clearly in favor of clemastine fumarate. Patients in all three treatment groups experienced drowsiness but both incidence and severity were lower with clemastine fumarate. 相似文献
62.
Nerve growth factor and substance P regulation in nasal sensory neurons after toluene diisocyanate exposure 总被引:1,自引:0,他引:1
Toluene diisocyanate (TDI) exposure produces rhinitis and nasal irritation, and increases the synthesis and release of substance P (SP) from airway sensory nerves. The mechanism leading to enhanced SP production following irritant inhalation remains unclear, but may involve actions of nerve growth factor (NGF). NGF binds trkA receptors located on sensory nerve terminals. Activation of trkA receptors initiates kinase-signaling cascades, which ultimately may increase SP. However, the effects of inhaled irritants on NGF release are not known. In this study, NGF levels in nasal lavages were examined following instillation of 10% TDI into both nasal cavities. NGF was significantly increased 2, 6, 12, and 24 h after TDI exposure compared with controls. The increase in NGF preceded the neuronal and mucosal increases in SP. Pretreatment with K252a, a nonselective tyrosine-kinase inhibitor, prevented the increase in SP-immunoreactivity in TG neurons and epithelial nerve fibers and the inflammatory response to TDI exposure. Because NGF binds to trkA tyrosine-kinase receptors, the NGF released during TDI exposure may mediate SP upregulation in airway sensory neurons, innervating the nasal cavity. 相似文献
63.
64.
We have examined the effect of reducing relative humidity (RH), with inbuilt mechanical ventilation and heat-exchange (MVHE) units, on house-dust- mite (HDM) counts and allergen levels, in a pilot study of 10 Wellington dwellings. Recent international prevalence studies in adults and children have confirmed a high prevalence of asthma in New Zealand, Sensitivity to HDM is common among the general population, and HDM is the major allergen associated with asthma. Recent studies of allergen levels have confirmed high concentrations of Der p 1 in the domestic environment. While humidity was significantly reduced in those dwellings fitted with ventilation units, no systematic effect on mites or Der p 1 was observed during the study period. When the reductions in humidity were examined in the context of the time spent below the critical equilibrium humidity (CEH), the intervention led to RH values below the CEH for only 39% of the total of 24-h periods for which measurements were made. Reducing RH by means of MVHE in New Zealand domestic dwellings does not lower humidity sufficiently, or long enough, to have any measurable effect on HDM populations. 相似文献
65.
The MDR1 polymorphisms at exons 21 and 26 predict steroid weaning in pediatric heart transplant patients 总被引:6,自引:0,他引:6
Zheng H Webber S Zeevi A Schuetz E Zhang J Lamba J Bowman P Burckart GJ 《Human immunology》2002,63(9):765-770
Various polymorphisms of the MDR1 gene that encodes for P-glycoprotein (P-gp), a transmembrane pump, have been identified. A silent mutation C3435T in exon 26 and a G2677T mutation in exon 21 have been correlated with P-gp expression and function in humans. The objectives of this study were (a) to determine whether the MDR1 exon 21 and exon 26 polymorphisms were related to steroid weaning in a pediatric heart transplant (HTx) population, and (b) to determine whether an association exist between the MDR1 exon 21 and exon 26 polymorphisms in these patients. Sixty-nine pediatric HTx patients were studied. MDR1 genotyping was determined by polymerase chain reaction amplification, sequencing the DNA, and sequence evaluation using Polyphred software (University of Washington) to identify genotypes. The steroid dose at 1 year post-transplantation was recorded. For steroid weaning at one year post-HTx for MDR1 C3435T, 12 of 18 (67%) patients in the CC genotype were still on prednisone, whereas only 18 of 47 (38%) of the CT/TT group were still receiving prednisone (p = 0.04). Similar results were observed for the MDR1 G2677T genotyping and steroid weaning. Forty-three of 46 patients (93.5%) who have MDR1 C3435T allele also have a mutant G2677T allele (p < 0.001). We conclude that (a) a significantly larger number of MDR1 3435 CC HTx patients remain on steroids at 1 year after transplantation, and (b) the MDR1 C3435T genotype is associated with the G2677 genotype in pediatric HTx patients. 相似文献
66.
Mark W. Musch Erin M. Davis-Amaral Herman H. Vandenburgh L. Goldstein 《Pflügers Archiv : European journal of physiology》1998,436(3):415-422
Cell volume expansion stimulates the efflux of solutes, including the amino acid taurine, to accomplish a regulatory volume
decrease (RVD). One protein that may play a role in taurine efflux is the cytosolic protein ICln. In rat neonatal cardiac
myocytes under isotonic conditions, ICln is found predominantly (greater than 90%) in the cytosol. However, after cell volume
expansion by exposure to hypotonic medium, ICln rapidly translocates to the particulate fraction (the Triton X-114-insoluble
fraction). After 2 min in hypotonic medium the percentage of ICln in the particulate fraction increases to 30%, 46% at 5 min,
40% at 10 min, and 25% at 30 min. The time course of this response is similar to that of hypotonicity-stimulated taurine efflux.
Hypotonicity-stimulated taurine efflux as well as ICln translocation parallel the reduction in medium osmolarity. As osmolarity
decreases, taurine efflux and ICln movement increase. The movement of ICln from the particulate back to the cytosolic fraction
is accelerated when volume-expanded cells are returned to isotonic medium. When ICln is analyzed under non-denaturing conditions,
a dimer is detected in the particulate fraction of volume-expanded cells, along with the monomer. This dimer is not detected
in the cytosol. Treatment of the particulate fraction from volume-expanded cells with the lyotropic agent KSCN caused release
of ICln but not Na-K-ATPase into the soluble fraction, indicating that translocated ICln associates with membranes in the
particulate fraction rather than inserting into them.
Received: 31 October 1997 / Received after revision and accepted: 23 March 1998 相似文献
67.
Elizabeth Dormandy Martin C Gulliford Erin P Reid Katrina Brown Theresa M Marteau 《The British journal of general practice》2008,58(548):154-159
BACKGROUND: Antenatal sickle cell and thalassaemia screening sometimes occurs too late to allow couples a choice regarding termination of affected fetuses. The target gestational age for offering the test in the UK is 10 weeks. AIM: To describe the proportion of women screened before 70 days' (10 weeks') gestation and the delay between pregnancy confirmation in primary care and antenatal sickle cell and thalassaemia screening. DESIGN OF STUDY: Cohort study of reported pregnancies. SETTING: Twenty-five general practices in two UK inner-city primary care trusts offering universal screening. METHOD: Anonymised data on all pregnancies reported to participating general practices was collected for a minimum of 6 months. RESULTS: There were 1441 eligible women intending to proceed with their pregnancies, whose carrier status was not known. The median (interquartile range [IQR]) gestational age at pregnancy confirmation was 7.6 weeks (6.0-10.7 weeks) and 74% presented before 10 weeks. The median gestational age at screening was 15.3 weeks (IQR = 12.6-18.0 weeks), with only 4.4% being screened before 10 weeks. The median delay between pregnancy confirmation and screening was 6.9 weeks (4.7-9.3 weeks) After allowing for practice level variation, there was no association between delay times and maternal age, parity, and ethnic group. CONCLUSION: About 74% of women consulted for pregnancy before 10 weeks' gestation but fewer than 5% of women were screened before the target time of 10 weeks. Reducing the considerable delay between pregnancy confirmation in primary care and antenatal sickle cell and thalassaemia screening requires methods of organising and delivering antenatal care that facilitate earlier screening to be developed and evaluated. 相似文献
68.
Toni Marie Torres-McGehee Dawn M. Emerson Erin M. Moore Stacy E. Walker Kelly Pritchett Allison B. Smith Taylor A. Lyles Greg Wakefield Kacey Ohlemeyer 《Journal of Athletic Training》2021,56(3):311
ContextResearch exists on energy balances (EBs) and eating disorder (ED) risks in physically active populations and occupations by settings, but the EB and ED risk in athletic trainers (ATs) have not been investigated.ObjectiveTo assess ATs'' energy needs, including the macronutrient profile, and examine ED risk and pathogenic behavioral differences between sexes (men, women) and job statuses (part time or full time) and among settings (college or university, high school, nontraditional).DesignCross-sectional study.SettingFree living in job settings.Patients or Other ParticipantsAthletic trainers (n = 46; male part-time graduate assistant ATs = 12, male full-time ATs = 11, female part-time graduate assistant ATs = 11, female full-time ATs = 12) in the southeastern United States.Main Outcome Measure(s)Anthropometric measures (sex, age, height, weight, body composition), demographic characteristics (job status [full- or part-time AT], job setting [college/university, high school, nontraditional], years of AT experience, exercise background, alcohol use), resting metabolic rate, energy intake (EI), total daily energy expenditure (TDEE), EB, exercise energy expenditure, macronutrients (carbohydrates, protein, fats), the Eating Disorder Inventory-3, and the Eating Disorder Inventory-3 Symptom Checklist.ResultsThe majority of participants (84.8%, n = 39) had an ED risk, with 26.1% (n = 12) engaging in at least 1 pathogenic behavior, 50% (n = 23) in 2 pathogenic behaviors, and 10.8% (n = 5) in >2 pathogenic behaviors. Also, 82.6% of ATs (n = 38) presented in negative EB (EI < TDEE). Differences were found in resting metabolic rate for sex and job status (F1,45 = 16.48, P = .001), EI (F1,45 = 12.01, P = .001), TDEE (F1,45 = 40.36, P < .001), and exercise energy expenditure (F1,38 = 5.353, P = .026). No differences were present in EB for sex and job status (F1,45 = 1.751, P = .193); χ2 analysis revealed no significant relationship between ATs'' sex and EB (= 0.0, P = 1.00) and job status and EB ( = 2.42, P = .120). No significant relationship existed between Daily Reference Intakes recommendations for all macronutrients and sex or job status.ConclusionsThese athletic trainers experienced negative EB, similar to other professionals in high-demand occupations. Regardless of sex or job status, ATs had a high ED risk and participated in unhealthy pathogenic behaviors. The physical and mental concerns associated with these findings indicate a need for interventions targeted at ATs'' health behaviors. 相似文献
69.
Tudor Kate Maloney Shannon Raja Anam Baer Ruth Blakemore Sarah-Jayne Byford Sarah Crane Catherine Dalgleish Tim De Wilde Katherine Ford Tamsin Greenberg Mark Hinze Verena Lord Liz Radley Lucy Opaleye Emerita Satiro Taylor Laura Ukoumunne Obioha C. Viner Russell Kuyken Willem Montero-Marin Jesus 《Prevention science》2022,23(6):934-953
Prevention Science - There is evidence that universal school-based mindfulness training (SBMT) can have positive effects for young people. However, it is unknown who benefits most from such... 相似文献
70.
Leah R. Ketcheson Erin E. Centeio Erin E. Snapp Hayley B. McKown Jeffrey J. Martin 《Disability and health journal》2021,14(1):100952
BackgroundChildren with intellectual and developmental disabilities (IDD) often experience increased barriers to engaging in physical activity (PA) which can stem from lack of gross motor function (GMF) development. Intervening on GMF at an early age can create better opportunities for children with IDD to engage in regular PA. In turn, increased PA can improve health outcomes and increase social skills.ObjectiveThe primary objective of this pilot study was to explore the effectiveness of a community-based GMF-focused PA intervention for improving overall motor skills and PA for children with IDD.MethodsAll study participants (n = 24) engaged in 10 weeks of programming for 1 h each week. A convenience sample was utilized.ResultsResults indicated no statistically significant changes pre to post for motor skill scores. However, a visual analysis of mean changes showed a consistent pattern of increased scores from pre to post on most skills. Additionally, we found that a change in participant locomotor skills significantly predicted change in Moderate to Vigorous Physical Activity (MVPA), F (1,11) = 5.16, Adj R2 = .26, p = .04.ConclusionsThese results suggest individualized attention on GMF may help to increase motor skills for children with IDD. This study adds to the small but growing amount of research examining the efficacy of community based adapted PA interventions. Further, study results should support continued exploration of effective approaches to address the motor delays experienced by children with IDD. 相似文献