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1.
The pattern of human late-phase skin reactions to extracts of aeroallergens   总被引:1,自引:0,他引:1  
The kinetics and dose response of cutaneous late phase reactions (LPR) (defined as greater than 5 mm induration 6 hours after intradermal challenge with allergen) were studied in 20 randomly selected subjects with atopic rhinitis. When subjects were challenged intradermally with 0.2 biologic unit (BU) of Dermatophagoides pteronyssinus or grass pollen, wheal-and-flare reactions were elicited without subsequent LPRs. With 30 BU, all subjects developed LPRs, whereas 1 and 10 BU provoked LPRs in 28% and 64%, respectively. No biphasic responses were detected. At all concentrations which progressed to form an LPR, a palpable skin reaction was continuously present and either remained constant or increased steadily in magnitude during 6 hours. Skin reactions of similar diameter provoked by histamine resolved fully within 2 hours. Thus, we confirm that the development of a macroscopic cutaneous LPR requires a higher concentration of allergen than the wheal-and-flare reaction. Together with our other findings, these results suggest that all untreated atopic individuals are capable of mounting an LPR if they are challenged with sufficient allergen. In contrast to the asthmatic response to inhaled allergen, the cutaneous wheal and LPR are not biphasic.  相似文献   

2.
BACKGROUND AND OBJECTIVES: The epidemiological association between higher dietary n-3 polyunsaturated fatty acids (PUFA) and lower prevalence of asthma, has led to interest in the role of early dietary modification in allergic disease prevention. In this study we examined the effects of maternal n-3 (PUFA)-rich fish oil supplementation on cord blood (CB) IgE and cytokine levels in neonates at risk of developing allergic disease. METHODS: In a randomized double-blind, placebo-controlled trial, 83 atopic pregnant women received either fish oil capsules (n = 40) containing 3.7 g n-3 PUFA/day or placebo capsules (n = 43) from 20 weeks gestation until delivery. CB cytokine levels (IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, TNF-alpha and IFN-gamma) and total IgE levels were measured and compared between the two groups. Fatty acid composition of red cell membranes was analysed by gas chromatography and the relationships among PUFA, cytokine and IgE levels were examined. RESULTS: Maternal fish oil supplementation resulted in a significant increase in n-3 PUFA levels (P < 0.001) in neonatal erythrocyte membranes. Neonates whose mothers had fish oil supplementation had significantly lower plasma IL-13 (P < 0.05) compared to the control group. There was also a significant inverse relationship between levels of n-3 PUFA in neonatal cell membranes and plasma IL-13. There was no difference in levels of IgE and the other cytokines measured. CONCLUSIONS: This study provides preliminary evidence that increasing neonatal n-3 PUFA levels with maternal dietary supplementation can achieve subtle modification of neonatal cytokine levels. Further assessment of immune function and clinical follow-up of these infants will help determine if there are any significant effects on postnatal immune development and expression of allergic disease.  相似文献   

3.
Cutaneous late-phase allergic reactions (LPR) are characterized by an early, immediate hypersensitivity whealing reaction followed by persistent, localized induration that peaks 6 to 8 hours later. In this study we used rodents to examine the relationship between vascular permeability (VP) and induration during LPR. Efflux of macromolecular tracers from the vasculature into skin was measured with the use of radiolabeled albumin and neutral dextran tracers having large molecular radii. To induce LPR immunologically, we used either intradermal injections of antirat IgE or passive cutaneous sensitization with IgE antidinitrophenyl followed 24 hours later by intravenous injection of albumin-dinitrophenyl. [125I]albumin and [3H]dextran tracers were injected intravenously before and at various intervals after the induction of LPR. Although a marked increase in VP occurred within the first 30 minutes after induction of mast cell degranulation, analysis of radiolabeled tracer accumulation at 2, 4, 8, and 24 hours failed to demonstrate any further increase in VP. These findings indicate that the induration observed in rodent LPR is not associated with increased VP beyond the immediate hypersensitivity stage and suggest that impairment of lymphatic drainage, cellular infiltration, and/or fibrin deposition are contributing factors.  相似文献   

4.
BACKGROUND: Anti-IgE (omalizumab) inhibited early and late asthmatic reactions and infiltration of inflammatory cells in asthmatic bronchial biopsies at baseline. The effect of chronic allergen exposure on these outcomes is unknown. Repeat allergen challenge in human skin represents a suitable model to address this question. OBJECTIVE: To study the effect of anti-IgE (omalizumab) on early-phase (EPR) and late-phase (LPR) skin reactions and cellular infiltration by using a repeat skin allergen challenge designed to imitate chronic allergen exposure. METHODS: Twenty-four atopic allergic volunteers received omalizumab or placebo for 12 weeks. Paired intradermal challenges of allergen (30 biological units) and diluent control were administered on 9 occasions at 2-week intervals. Early-phase and late-phase skin reactions and cellular infiltration in skin biopsies (using immunohistochemistry and in situ hybridization) were measured at intervals. RESULTS: Compared with placebo, omalizumab-treated patients had a progressive reduction in the LPR that was significantly greater than its effect on the EPR (median, --63% vs--24% respectively; P=.009). In addition, significant reduction of the LPR was reached within 2 weeks of commencing treatment, compared with 8 weeks for the EPR. There was a priming effect of repeated allergen challenge on infiltration of eosinophil, neutrophil, T(H)2 (CD3(+)/IL-4(+)), and total FcepsilonRI(+) cells in patients on placebo that was abrogated in those receiving omalizumab. CONCLUSION: The more marked effect of omalizumab on the LPR and prevention of the repeat-dose priming effect on several inflammatory cell types support a role for anti-IgE treatment in conditions associated with chronic allergic inflammation.  相似文献   

5.
The effect of daily dietary supplementation with 15 to 20 mL of evening primrose seed oil or fish oil was assessed by comparison with olive oil as placebo in a cross-over study in 29 asthmatics. During 10 weeks of each regimen, the patients kept record of symptoms, peak expiratory flow rates and medication. Plasma and urine TxB2, PGE2, PGF2 alpha and 6 keto-PGF1 alpha and plasma fatty acid composition of plasma cholesterol esters were measured at the end of each treatment period. There were no differences between regimes with regard to peak flow rates, symptoms, or drug consumption. Plasma PGE2 levels increased during the fish oil treatment but there were no changes in other prostanoids in plasma or urine. The fatty acid pattern of plasma cholesterol esters showed significant differences between the supplementation periods. We conclude that moderate doses of evening primrose oil or fish oil are ineffective as a supplementary treatment of bronchial asthma.  相似文献   

6.
The aim of this study was to determine the effects of dietary supplementation with a combination of fish oil, bilberry extract, and lutein on subjective symptoms of asthenopia in humans by a double- blind, randomized, parallel-group, and placebo-controlled trial. In the Active group, eleven subjects ingested a supplement containing omega-3 fatty acid-rich fish oil (docosahexaenoic acid 783 mg/day, eicosapentaenoic acid 162 mg/day), bilberry extract (anthocyanidin 59 mg/day), and lutein (17.5 mg/day) in soft gel capsule form, every day for 4 weeks. In the Placebo group, nine subjects ingested placebo capsules. Before and after supplementation, subjects completed a questionnaire to determine their asthenopia symptoms and were also assessed for mental fatigue symptom by the visual analog scale (VAS) test. Asthenopia symptoms such as "stiff shoulder, low back pain", "frustration", "dry-eye", and "stuffy head" were improved in the Active group. Furthermore, a score of mental fatigue was improved after 4 weeks of supplementation, and no side effects were observed after the 4-week supplementation and a 2-week washout period in the Active group. These results suggest that dietary supplementation with the combination of omega-3 fatty acid-rich fish oil, bilberry extract, and lutein may safely improve subjective symptoms of asthenopia and mental fatigue in humans.  相似文献   

7.
The effect of topical glucocorticosteroids on the allergen-induced nasal hyperresponsiveness, with special reference to treatment time, was studied in a double-blind, randomized, placebo-controlled crossover study. Ten patients who previously had shown allergen-induced nasal hyperresponsiveness participated. After pretreatment with either placebo or various periods with topical glucocorticosteroids, they were subjected to an initial challenge with three increasing doses of allergen and were rechallenged after 24 hours with the lowest allergen dose from the previous day. The nasal responses were monitored by means of symptom scores and measurements of N alpha-p-tosyl-L-arginine methyl esterase (TAME) activity in nasal lavages. Five different treatment schedules were used. In the active treatment alternatives, the glucocorticosteroid treatment was started 48, 12 or 2 hours before or 2 hours after the initial allergen challenge. All treatments were continued up to rechallenge on the second day. As the active treatment we used budesonide, 100 micrograms in each nasal cavity every 12 hours. After placebo pretreatment, as expected, there was an increase in nasal symptoms at rechallenge as compared with the initial allergen challenge with the same allergen dose. The mean (+/- SEM) number of sneezes increased from 5.1 +/- 1.7 to 9.5 +/- 2.0 (p less than 0.05), a composite nasal symptoms score increased from 3.3 +/- 0.66 to 4.4 +/- 0.7 (NS), and TAME activity increased from 14.9 +/- 2.83 to 25.3 +/- 0.5 cpm.10(3) (p less than 0.05). Topical glucocorticosteroid treatment abolished this increase in nasal symptoms and TAME activity (p less than 0.05 for all treatment alternatives).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

8.
Serum lipid responses to dietary modification are partly determined by genetic factors. The objective of the present study was to investigate the influence of the Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-gamma2 (PPAR-gamma2) gene on serum lipid and lipoprotein responses to n-3 fatty acid supplementation. A total of 76 men and 74 women (age 49+/-8 years, body mass index 26.5+/-3.0 kg/m(2)) participated in a controlled multi-center study. Subjects were randomly assigned to consume either fish oil supplements (3.6g n-3 fatty acids/day containing 2.4 g of EPA and DHA) or placebo capsules containing olive oil for 3 months. At baseline, the Pro12Ala polymorphism was not associated with serum total and lipoprotein lipid concentrations or lipoprotein lipase activity in the fasting state. After the 3-month study period, carriers of the Ala12 allele presented a greater decrease in serum triacylglycerol concentration in response to n-3 fatty acid supplementation than did subjects with the Pro12Pro genotype when the total dietary fat intake was below 37 E% (p=0.003) or the intake of saturated fatty acids was below 10 E% (p=0.006). Changes in serum total cholesterol, serum LDL cholesterol and HDL cholesterol concentrations were similar among the genotypes in the n-3 fatty acid supplementation group and in the placebo group. In conclusion, the Pro12Ala polymorphism of the PPAR-gamma2 gene may modify the inter-individual variability in serum triacylglycerol response to n-3 fatty acid supplementation.  相似文献   

9.
Background Exposure of atopic patients to a specific allergen evokes an immediate response which is followed, in many cases, by a late phase reaction (LPR) some hours later. Here we have examined the immunological mechanisms required for the expression of cutaneous LPR in mice. Methods BALB/c mice were immunized by i.p. injection of ovalbumin (OVA) and alum actively or by i.v. injection of anti-OVA IgE monoclonal antibody (mAb) passively. After challenge by intradermal injection of OVA into ears, the changes in ear thickness, the number of eosinophils, and the levels of IL4 and IFN-γ protein at the site of antigen challenge were examined. Results Actively immunized mice developed a biphasic response at the site of OVA injection, while mice passively immunized with IgE anti-OVA mAb displayed a strong early response but no LPR. Cell transfer experiments using BALB/c nu/nu mice revealed that both OVA-specific IgE mAb and OVA-primed CD4 T cells were required to evoke LPR. Moreover, LPR was associated with increased levels of IL-4 production concomitant with reduced IFN-γ production and was abolished by pretreatment with anti-IL-4 neutralizing mAb. Conclusion It is suggested that murine cutaneous LPR against OVA is a type 2 inflammatory response in which both IgH antibodies and CD4 T cells play an obligatory role.  相似文献   

10.
BACKGROUND: Butterbur or Petasites hybridus is an herbal remedy that exhibits antihistamine and antileukotriene activity and has been shown to attenuate the response to adenosine monophosphate challenge in patients with allergic rhinitis and asthma. However, no data are available regarding its effects on the histamine and allergen cutaneous response. OBJECTIVE: To evaluate the effects of butterbur compared with fexofenadine and montelukast on the histamine and allergen wheal and flare cutaneous responses. METHODS: Atopic patients were randomized into a double-blind, double-dummy, crossover study to receive for 1 week butterbur, 50 mg twice daily (8 AM and 10 PM); fexofenadine, 180 mg once daily (10 PM), and placebo once daily (8 AM); montelukast, 10 mg once daily (10 PM), and placebo once daily (8 AM); or placebo twice daily (8 AM and 10 PM). Patients attended the department at 10 AM and had measurements of the cutaneous wheal and flare responses to histamine, allergen, and saline control at 10-minute intervals for 60 minutes. RESULTS: Twenty patients completed the study. The mean +/- SE histamine wheal and flare responses, respectively, were significantly attenuated (P < .05) by fexofenadine (9.4 +/- 1.8 mm2 and 13.5 +/- 3.2 mm2) compared with placebo (15.5 +/- 3.3 mm2 and 179.8 +/- 74.3 mm2) but not by butterbur (16.4 +/- 2.1 mm2 and 297.7 +/- 121.2 mm2) or montelukast (19 +/- 1.9 mm2 and 240.2 +/- 66.6 mm2). The allergen wheal and flare responses, respectively, were also significantly attenuated (P < .05) by fexofenadine (31.1 +/- 6.3 mm2 and 256.9 +/- 86.5 mm2) compared with placebo (65.4 +/- 15.2 mm2 and 1,014.5 +/- 250.0 mm2) but not by butterbur (50.4 +/- 9.2 mm2 and 1,110.3 +/- 256.1 mm2) or montelukast (58.8 +/- 9.1 mm2 and 1,463.6 +/- 295.6 mm2). CONCLUSIONS: Butterbur did not produce any significant effects on the histamine and allergen cutaneous response compared with placebo, whereas mediator antagonism with fexofenadine but not montelukast produced significant attenuation. This finding would suggest that butterbur may not be effective in allergic skin disease.  相似文献   

11.
BACKGROUND: There is growing interest in the potential role of anti-inflammatory n-3 polyunsaturated fatty acids (n-3 PUFAs) in the prevention of allergic disease. OBJECTIVE: We sought to determine whether maternal dietary supplementation with n-3 PUFAs during pregnancy could modify immune responses in infants. METHODS: In a randomized, controlled trial 98 atopic, pregnant women received fish oil (3.7 g n-3 PUFAs per day) or placebo from 20 weeks' gestation until delivery. Neonatal PUFA levels and immunologic response to allergens were measured at birth. RESULTS: Eighty-three women completed the study. Fish oil supplementation (n = 40) achieved significantly higher proportions of n-3 PUFAs in neonatal erythrocyte membranes (mean +/- SD, 17.75% +/- 1.85% as a percentage of total fatty acids) compared with the control group (n = 43, 13.69% +/- 1.22%, P <.001). All neonatal cytokine (IL-5, IL-13, IL-10, and IFN-gamma) responses (to all allergens) tended to be lower in the fish oil group (statistically significant only for IL-10 in response to cat). Although this study was not designed to examine clinical effects, we noted that infants in the fish oil group were 3 times less likely to have a positive skin prick test to egg at 1 year of age (odds ratio, 0.34; 95% confidence interval, 0.11 to 1.02; P =.055). Although there was no difference in the frequency of atopic dermatitis at 1 year of age, infants in the fish oil group also had significantly less severe disease (odds ratio, 0.09; 95% confidence interval, 0.01 to 0.94; P =.045). CONCLUSIONS: These data suggest a potential reduction in subsequent infant allergy after maternal PUFA supplementation. More detailed follow-up studies are required in larger cohorts to establish the robustness of these findings and to ascertain their significance in relation to longer-term modification of allergic disease in children.  相似文献   

12.
A new H1 antihistamine, cetirizine, was studied to determine its effects on mediators and cellular infiltration during the cutaneous late-phase response (LPR). Ten ragweed-allergic subjects, who had previously demonstrated a cutaneous LPR, were examined in a double-blind, crossover study. Either cetirizine, 20 mg, or placebo was administered orally once daily for 2 days before and the morning of placement of a skin chamber overlying an unroofed heat/suction-induced blister to which was added antigen or buffer. Skin test erythema was significantly reduced by cetirizine at 15 minutes, 2 hours, and 4 hours by 56%, 40%, and 39%, respectively (all, p less than or equal to 0.01), but by 6 and at 8 hours, the cutaneous erythema was not significantly lessened. Histamine release was not altered by cetirizine treatment, but prostaglandin D2 (PGD2) production, which peaked at 3 to 5 hours, was clearly reduced by cetirizine treatment, being lower at all time points during the reaction; this was significant by analysis of variance (p less than or equal to 0.04). The inhibition was most marked during the fifth hour of the reaction when there was a 50% suppression of the PGD2 level by cetirizine (0.193 ng/ml to 0.075 ng/ml [p less than or equal to 0.03]). The most dramatic effect of cetirizine was attenuation of the inflammatory cell migration into the chamber. Eosinophil infiltration was decreased by about 75% during hours 6, 7, and 8 (p less than or equal to 0.04), whereas the number of neutrophils was reduced by the same magnitude at the same times (p less than or equal to 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

13.
The cutaneous late-phase reaction (LPR) to ragweed was studied in untreated ragweed-allergic individuals and patients receiving 3 to 5 years of immunotherapy demonstrating clinical improvement. The magnitude of immediate skin reactions and the initial levels of the specific IgE and IgG antiragweed antibodies were similar in both groups. The LPR was elicited by administering a skin test with ragweed extract at 10 times the concentration required to elicit a 4 + immediate reaction and appeared as an erythematous-edematous lesion associated with pruritus. In the untreated group 94% developed an LPR (59 +/- 32 mm at 4 hours and 67 +/- 30 mm at 8 hours) at this dose. In the treated group only one third developed an LPR, one third had partial response measurable at one of these two times, and one third failed to develop any LPR (21 +/- 20 mm at 4 hours, p less than 0.002, and 20 +/- 22 mm at 8 hours, p less than 0.001). Therapy resulted in a twentyfold increase of IgG antiragweed level and in a decline of IgE antiragweed. The size of the LPR correlated inversely with the level of IgG antiragweed (p less than 0.01; r = -0.52) but not with IgE antibody. Thus, in a retrospective analysis immunotherapy was associated with the suppression of the skin LPR, and the magnitude of the LPR was correlated with the level of IgG antiragweed. We suggest that the clinical efficacy of immunotherapy is related in part to effects on the LPR.  相似文献   

14.
BACKGROUND: Although there has been much study of the histologic features of the late-phase reactions (LPR) seen 6 to 24 hours after intradermal injection of allergens, much less is known about the events occurring during development of such LPR. OBJECTIVE: Our purpose was to compare sequential gross and histologic inflammatory responses during developing skin LPR within 6 hours after challenge. METHODS: Gross reactions were measured and biopsy specimens obtained at 20 minutes and 1, 2, and 6 hours after intradermal allergen (Ag) and buffer diluent control (B) injections in 7 atopic subjects with known immediate and LPR. Inflammatory cell responses were compared, as detected by immunohistochemistry in Ag and B sites. These findings were then compared with those at 24 hours. RESULTS: Gross LPR evolved without a hiatus from the immediate wheal responses over the next 6 hours (P =.04 vs that in B sites) and then decreased by 24 hours. Prominent PMN accumulation started by 20 minutes, peaking at 1 hour (P <.01). Eosinophil accumulation was significant, starting at 1 hour (P <.001) and peaking at 6 hours (P < .001). Many eosinophils were activated (EG(2)(+)). T-cell accumulation started at 2 hours (P =.01) and was most prominent at 24 hours. The frequency of vessels expressing E-selectin increased at 1 hour (P <.005), correlating with the degree of local PMN accumulation. The frequency of vessels expressing vascular cell adhesion molecules started increasing at 6 hours (P = .02), well after eosinophil accumulation was prominent. CONCLUSIONS: Skin LPR is characterized by evolution of a gross indurated reaction from the immediate whealing response over the first 6 hours after intradermal Ag challenge, with an early accumulation of PMN and eosinophils, not directly attributable to lymphocyte entry or vascular cell adhesion molecule expression. Likely, multiple other factors may also play roles in the complex pathogenesis of LPR.  相似文献   

15.
A number of recent studies have assessed the impact of dietary omega-3 polyunsaturated fatty acids (n-3 PUFAs) on behavioral outcomes; however, very little attention has been given to their impact upon brain function in physiological terms. Sixty-five healthy adults aged 18-29 yrs took part in this double-blind, placebo-controlled study assessing the effects of 12 weeks daily dietary supplementation with docosahexaenoic acid-rich fish oil (1 g, 2 g) or placebo (olive oil). Relative changes in the concentration of oxyhemoglobin and deoxyhemoglobin were assessed in the prefrontal cortex using near-infrared spectroscopy during performance of nine computerized cognitive tasks. Supplementation with both doses of fish oil, in comparison with placebo, resulted in significantly increased concentrations of oxyhemoglobin and total levels of hemoglobin, indicative of increased cerebral blood flow, during the cognitive tasks. Changes in hemodynamic response to tasks were not accompanied by consistent changes in cognitive performance.  相似文献   

16.
To determine whether oral slow-release theophylline inhibits asthmatic reactions and the associated increase of airway responsiveness to methacholine induced by allergens, we examined six asthmatic subjects who developed a dual asthmatic reactions after allergen bronchoprovocation with Dermatophagoides pteronyssinus or with grass pollen. We gave oral slow-release theophylline and placebo to each subject for seven days in two series of experiments in a double-blind, randomized, crossover study. The individual daily dose of theophylline (4.7 to 16.6 mg/kg/day, divided into two doses) was calculated for each subject by measuring individual theophylline clearance and optimal daily dosage. During treatment with placebo, the subjects developed dual asthmatic reactions, ie, FEV1 decreased from 4.1 +/- 0.17 L before bronchoprovocation to 3.2 +/- 0.14 L at 15 minutes and to 3.2 +/- 0.19 L at seven hours after allergen bronchoprovocation. By contrast, during active treatment FEV1 decreased from 4.2 +/- 0.28 L to 3.9 +/- 0.26 L at 15 minutes, and to 3.8 +/- 0.13 L at seven hours (both cases, P less than .03 compared with placebo). Mean serum theophylline concentration was 13.2 +/- 0.6 mg/L. Although 1 week's treatment with slow-release theophylline did not modify significantly either prechallenge airway responsiveness to methacholine or its increase after allergen inhalation challenge, in five out of six subjects theophylline significantly inhibited the increase of airway responsiveness to methacholine induced by allergens compared to placebo and control day (P less than .05). These results suggest that slow-release theophylline may inhibit allergen-induced asthmatic reactions and the associated increase of airway responsiveness, suggesting some antiinflammatory effects for this drug.  相似文献   

17.
There has been considerable debate about how copper status may affect the biochemical and cellular processes associated with atherogenesis. We have investigated the effects of graded dietary copper supplementation on processes likely to contribute to atherogenesis, using the cholesterol-fed New Zealand White rabbit model. Rabbits (n = 40) were fed a 0.25-1% cholesterol diet deficient in copper. Animals received either 0, 1, 3 or 20 mg copper/day and were killed after 13 weeks. Plasma cholesterol levels were similar in each dietary group. Aortic concentrations of copper were higher in the 20 mg copper/day animals compared to those receiving 0 mg copper/day (3.70 +/- 0.78 vs. 1.33 +/- 0.46 microg/g wet tissue; P < 0.05). Aortic superoxide dismutase activity was higher in animals receiving 20 mg copper/day (323 +/- 21 IU/mg tissue) compared to the other groups (187 +/- 21; 239 +/- 53; 201 +/- 33 IU/mg tissue) (P > 0.05). En face staining of aortae with oil red O showed that both high copper supplementation (20 mg/day) (67.1 +/- 5.5%) and a deficient diet (0 mg/day) (63.1 +/- 4.8%) was associated with significantly larger lesions (P < 0.05) compared to moderately supplemented animals (1 mg/day and 3 mg/day) (51.3 +/- 6.3 and 42.8 +/- 7.9%). These data indicate that in the cholesterol-fed rabbit, there is an optimal dietary copper intake and that dietary copper deficiency or excess are associated with an increased susceptibility to aortic atherosclerosis. Many Western diets contain insufficient copper and these findings indicate that a moderate dietary copper content may confer a degree of cardiac protection to the human population.  相似文献   

18.
This study is of the effect of the blockade of histamine H1 receptors by a long-acting antihistamine on the immediate and late clinical response to antigen (Ag) and on the recruitment of eosinophils in the late-phase cutaneous reaction. Ten adult volunteers with late-phase reactions to the intradermal injection of either Dermatophagoides pteronyssinus or Phleum pratense (timothy) pollen performed a double-blind, crossover study. Each volunteer took astemizole, 10 mg, or identical placebo, daily for 2 weeks. Ag in the concentration that induced a late reaction in the screening visit was injected intradermally at the end of each drug period. The early reaction was measured serially for 30 minutes and the late reaction at 4 and 6 hours. Biopsies of the Ag and control sites were also performed at 6 hours. After a 6-week washout period, subjects then took the opposite medication for 2 weeks and returned for skin testing and biopsy. Skin testing demonstrated that astemizole inhibited the immediate response to both histamine and allergen but had no effect on the late response at 4 hours and at 6 hours. Biopsy specimens revealed no significant effect on eosinophil recruitment at 6 hours. We conclude that histamine H1-receptor blockade has no effect on the late cutaneous reaction to Ag.  相似文献   

19.
A comparison of adrenocortical function before and after treatment with either intranasal triamcinolone acetonide aerosol (ITAA), prednisone, or placebo was done. Sixty-two male subjects with allergic rhinitis were treated for 6 weeks with either ITAA (220 or 440 micrograms/day), oral prednisone (10 mg/day), or placebo in double-blind, parallel-group fashion. Adrenocortical function was assessed by 6-hour cosyntropin stimulation before and at the end of the treatment period. The placebo-treated and two ITAA-treated groups produced no changes in adrenocortical function with treatment, and the ITAA-treated groups were not different from the placebo-treated group with mean +/- SEM changes in stimulated plasma cortisol (micrograms per deciliter) as follows: placebo, -2.68 +/- 1.77; ITAA 220 micrograms, -2.69 +/- 1.18; ITAA 440 micrograms, -2.96 +/- 1.81. The prednisone-treated group had a mean reduction in adrenocortical function (mean +/- SEM change in stimulated plasma cortisol of -19.8 +/- 1.77 micrograms/dl) that was significant (p less than 0.0001) compared with that of the placebo-treated group. The results of this study indicate that 6 weeks of treatment with 220 micrograms/day or 440 micrograms/day of ITAA has no effect on adrenocortical function, but prednisone, at a dosage of 10 mg/day for 6 weeks, produces partial adrenocortical suppression.  相似文献   

20.
The protective effects of deflazacort against the inflammation that follows the conjunctival provocation test (CPT) by specific allergen were assessed in 24 patients with rhinoconjunctivitis caused by Parietaria judaica in a double-blind study. After a screening CPT, patients were randomized into four treatment groups, each being given deflazacort (oral tablets) at 6, 30, and 60 mg once daily, or matching placebo, for 3 d, outside the pollen season. Clinical evaluation (itching, hyperemia, lacrimation, and swelling of eyelids) and cytologic assessment (number of inflammatory cells in conjunctival scraping and evaluation of ICAM (intercellular adhesion molecule)-1/CD54 expression on epithelial cells) were performed at base line, 30 min (early-phase reaction (EPR), 6 h and 24 h (late-phase reaction (LPR)) after specific CPT, and before and after treatment. Neither the EPR clinical reactions nor the EPR total number of inflammatory cells was modified by deflazacort. However, the LPR clinical effects were significantly reduced by deflazacort at 30 or 60mg/d ( P <0.01), as compared with placebo. The total number of inflammatory cells during LPR was significantly reduced by deflazacort at 30 or 60 nig/d (( P <0.01), as compared with placebo. Furthermore, CD54 expression was significantly reduced by deflazacort at 30 or 60 mg/d both in the EPR (( P <0.01) and LPR (( P <0.01), as compared with placebo. None of the studied indicators were modified at the 6 mg/d dose. This study shows that deflazacort has a highly protective action against clinical and cellular LPR effects induced by the specific CPT, In addition, deflazacort markedly reduces CD54 expression on the conjunctival epithelium during both EPR and LPR.  相似文献   

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