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M Müller J Grunewald C Olgart H?glund B Dahlén A Eklund H Stridh 《The European respiratory journal》2006,28(3):513-522
The increased number of lymphocytes in airways during an asthmatic response is believed to be the result of increased recruitment of these cells. However, it is possible that a decreased apoptotic rate could also contribute to the increased number. The aim of the present study was to investigate whether allergen airway provocation influences the apoptotic phenotype of lung and peripheral blood lymphocytes (PBL) in subjects with atopic asthma. Bronchoalveolar lavage (BAL) lymphocytes and PBL from 12 asthmatic subjects previously challenged with allergen (n = 7) or saline (n = 5) were exposed to the apoptotic stimulus tributyltin (TBT) in vitro and assayed for apoptosis. Airway allergen provocation resulted in decreased sensitivity of BAL lymphocytes to TBT-induced apoptosis, with 42.2% (range 33.9-62.5%) apoptotic cells before challenge versus 23.5% (range 15.3-42.4%) after challenge, while PBL were unaffected. The increased apoptosis resistance correlated with higher numbers of Bcl-2-expressing lymphocytes. Interestingly, baseline caspase-3-like activity was significantly elevated in viable BAL lymphocytes compared with viable PBL, and was unaltered by allergen exposure. In conclusion, allergen inhalation renders bronchoalveolar lavage lymphocytes more resistant to apoptosis while peripheral blood lymphocytes were not influenced at all, indicating that the apoptotic phenotype of airway lymphocytes may play a role in asthmatic inflammation. 相似文献
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Erika E Forbes Douglas E Williamson Neal D Ryan Boris Birmaher David A Axelson Ronald E Dahl 《Neuropsychopharmacology》2006,59(1):24-30
BACKGROUND: Changes in the hypothalamic-pituitary-adrenal (HPA) axis, as evidenced by patterns of cortisol secretion, have been of interest in understanding depression and anxiety disorders across the life span. Previous studies of pediatric depression have pointed to the period around sleep onset as a key time point for observing alterations in cortisol secretion associated with affective disorders. Evidence also indicates that pubertal development may influence the expression of HPA dysregulation. We hypothesized that adolescents with depression and youth with anxiety disorders exhibit elevated peri-sleep-onset cortisol. METHODS: Plasma cortisol was sampled every 20 min around sleep onset from children and adolescents with major depressive disorder (n = 116), anxiety disorders (n = 32), or no history of psychiatric disorder (control; n = 76). Sleep onset was determined by polysomnography. Classification of participants as children or adolescents was based on Tanner staging of pubertal maturation. RESULTS: Children with anxiety disorders had higher peri-sleep-onset cortisol than children with depression or control children. Adolescents with depression had marginally higher peri-sleep-onset cortisol than control adolescents and significantly higher peri-sleep-onset cortisol than children with depression. CONCLUSIONS: Depression and anxiety are associated with altered cortisol secretion around sleep onset, and these changes appear to be influenced by pubertal maturation. 相似文献
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The fate of isoprene inhaled by rats: comparison to butadiene 总被引:1,自引:0,他引:1
A R Dahl L S Birnbaum J A Bond P G Gervasi R F Henderson 《Toxicology and applied pharmacology》1987,89(2):237-248
Isoprene (2-methyl-1,3-butadiene), a volatile monomer occurring in the natural environment and used in the manufacture of elastomers, is a close chemical relative of the animal carcinogen 1,3-butadiene. To obtain toxicokinetic data for inhaled isoprene, male F344 rats were exposed in groups of 30 to 14C-labeled isoprene vapor at four concentrations from 8 to 8200 ppm. The percentage of the inhaled isoprene that was metabolized decreased with increasing exposure concentration. The percentage of the total metabolites (that is, non-isoprene-retained 14C) excreted in urine and feces or expired was determined as a function of vapor concentration. About 75% of the total metabolites was excreted in urine. This was independent of inhaled isoprene concentration. After exposure to 8200 ppm, a larger percentage of the metabolites was excreted in feces than after exposure to lower concentrations. Using vacuum line techniques, blood metabolite concentrations were determined as functions of both vapor concentration and exposure duration. At one exposure concentration (1480 ppm) metabolites were measured in the nose, lungs, liver, kidney, and fat, as well as in blood. A mutagenic metabolite, isoprene diepoxide, was tentatively identified in all tissues examined. Between 0.0018 and 0.031% of the inhaled 14C label was tentatively identified as this metabolite in blood. The relative amount of the metabolites present in blood was highest for low concentrations of inhaled isoprene and for shorter exposure durations. Body fat appeared to be a reservoir for both isoprene metabolites and isoprene itself. The appearance of metabolites in the respiratory tract after short exposure durations together with low blood concentrations of isoprene indicated that substantial metabolism of inhaled isoprene in the respiratory tract may occur. 相似文献
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Clonidine (10 micrograms X kg-1) reduced by almost 50% the increase in plasma neuropeptide (NPY)-like immunoreactivity (-LI) induced by preganglionic nerve stimulation at 8 Hz. This effect was reversed by yohimbine (1 mg X kg-1) which caused a three-fold increase of the plasma NPY-LI. Prazosin (1 mg X kg-1) had no such effect. Guanethidine (5 mg X kg-1) reduced the stimulation-evoked increase in plasma NPY-LI. It is concluded that the release of NPY-LI evoked by nerve stimulation from sympathetic nerve terminals is controlled by a presynaptic alpha 2-adrenoceptor-mediated mechanism. 相似文献
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Clinical aspects of pelvic inflammatory disease 总被引:2,自引:0,他引:2
Pelvic inflammatory disease (PID) is a common and poorly managed condition.
Untreated or inadequately treated, it leads to tubal infertility, ectopic
pregnancy and chronic pelvic pain. Diagnostic difficulties are compounded
by the wide variety of clinical presentations and the insensitivity and
poor specificity of laboratory tests. Better recognition of mild and
atypical disease needs a high index of suspicion whenever young, sexually
active women present with gynaecological symptoms. Laparoscopy supplemented
by microbiological tests and fimbrial minibiopsy should be regarded as the
diagnostic 'gold standard' for research studies; new studies are required
to identify techniques which might reduce under- and over-diagnosis. Early
treatment reduces the risk of an adverse effect on fertility. Any
therapeutic regimen selected should be effective against the common
aetiological agents Chlamydia trachomatis, Neisseria gonorrhoeae, genital
mycoplasmas and aerobic and anaerobic bacteria. Since at least 60% of cases
of PID can be attributed to infection with a sexually transmitted organism,
partner notification forms an essential part of management.
相似文献
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Effect of nicotine, silver acetate, and ordinary chewing gum in combination with group counselling on smoking cessation. 下载免费PDF全文
Four hundred and ninety six smokers participated in a randomised comparison of the effect of silver acetate, nicotine, and ordinary chewing gum on smoking cessation. All were motivated to stop smoking abruptly and all had smoked at least 10 cigarettes a day for at least five years. Side effects and taste acceptability were related to outcome after six months. The participants attended nine meetings over a year, at which lectures, support, and advice about stopping smoking were given. Tobacco abstinence was confirmed by measurement of carbon monoxide in expired air. The chewing gums were used for 12 weeks. After 12 weeks there was a trend towards more abstainers in the nicotine group (59%) than in the silver acetate (50%) and ordinary (45%) chewing gum groups that was not quite significant (p = 0.07). At 26 and 52 weeks the number of cigarette abstainers was similar in the three treatment groups. Subjects in the nicotine chewing gum group had a longer mean time before relapse than those in the silver acetate and ordinary chewing gum groups. Mean success rates for all subjects combined at 12, 26, and 52 weeks were 52.8%, 39.7%, and 23.3%. The side effects of nicotine and silver acetate chewing gum were generally mild and transient, and unimportant except for mouth irritation from silver acetate, which had a negative effect on outcome, and the low taste acceptability of nicotine, which had a strong negative influence on the success rate. The results suggest a short term effect on nicotine chewing gum on smoking cessation, but the abstinence rates after one year were generally disappointing. 相似文献