Reproducibility of nasal allergen challenge in evaluating the efficacy of intranasal corticosteroid treatment.

BACKGROUND: Although nasal challenge with allergen has often been used to evaluate the efficacy of therapeutic modalities used for the treatment of allergic rhinitis, the reproducibility of this model in quantitatively evaluating efficacy has not been rigorously examined. OBJECTIVE: To examine the reproducibility of the suppressive effects of an intranasal corticosteroid on the clinical and biochemical outcomes of a nasal allergen challenge during two identical treatment periods using the same subjects. METHODS: In a single-blind study, 25 seasonal allergic subjects with positive skin tests to grass or ragweed were studied outside of their pollen season. Subjects underwent a baseline, three-dose allergen challenge. Beginning 1 week later, subjects received two 7-day courses of intranasal beclomethasone (168 microg b.i.d.) separated by a 1-month washout period. Nasal challenges with allergen were performed after each treatment period. The nasal allergic response was evaluated by counting sneezes, recording symptom scores and measuring levels of albumin (an index of vascular permeability), lysozyme (an index of serous glandular secretion) and kinins (proinflammatory peptides) in recovered nasal lavages. RESULTS: Compared with the baseline challenge, each course of beclomethasone significantly reduced sneezing, symptom scores, albumin and kinins, but not lysozyme. Reproducibility analysis of the net changes from diluent challenge in the two beclomethasone treatment periods, showed the following intraclass correlation coefficients: sneezing (0.92), lysozyme (0.82), symptom scores (0.72), albumin (0.64) and kinins (0.28). CONCLUSION: We conclude that the nasal challenge model is a reproducible method to evaluate the efficacy of anti-allergic medications. For nasal corticosteroid trials, sneezing, symptom scores and albumin levels are recommended as the most reproducibly suppressive outcome measures.

Ineffectiveness of echinacea for prevention of experimental rhinovirus colds.

The purpose of this study was to assess the effectiveness of echinacea for the prevention of experimental rhinovirus colds. Infection occurred in 44 and 57% and illness occurred in 36 and 43% of the echinacea- and placebo-treated subjects, respectively. This preparation of echinacea had no significant effect on either the occurrence of infection or the severity of illness.

An evaluation of nasal response following different treatment regimes of oxymetazoline with reference to rebound congestion.

This was a randomized, double-blind vehicle controlled study aimed at investigating the effects on nasal function of 7 days treatment with the topical decongestant oxymetazoline (0.05% w/v). Fifty healthy volunteers took part in the study and these were randomly allocated to three treatment groups (i) daily oxymetazoline (b.i.d. 150 microliters per nostril) (ii) intermittent oxymetazoline, with oxymetazoline being substituted for vehicle at the morning doses on days 1, 3, and 7; and (iii) daily vehicle (b.i.d. 150 microliters per nostril). The nasal airway was assessed by measurement of nasal airway resistance (NAR) using posterior rhinomanometry, subjective scaling of nasal patency by means of a visual analogue scale (VAS), and clinical visual examination. On days 1, 2, 3, and 7, NAR and VAS measurements were obtained before the morning dose and up to 6 hours after dosing; clinical visual examinations were also performed before dosing on these days. NAR and VAS measurements were also made following withdrawal of treatment on Days 8 and 9. Nonparametric analysis of the results showed that therapeutic tolerance to oxymetazoline did not develop over the 7-day treatment period, and visual examination of the nasal mucosa failed to find significant evidence of rhinitis. Evidence of rebound nasal congestion was found following 3 days of oxymetazoline treatment, with baseline NAR within the daily and intermittent oxymetazoline groups being significantly greater on Day 3 compared to Day 1 (p < 0.05). However, there was a trend toward increasing baseline NAR in the vehicle group over the course of the study, suggesting that the vehicle may have contributed to the rebound congestion. Following the withdrawal of treatments, only the intermittent oxymetazoline group had significantly higher NAR on Days 8 and 9 compared to Day 1 (p < 0.05). Subjective VAS measurements generally followed trends in NAR.

Characterization of daytime sleepiness and psychomotor performance following H1 receptor antagonists.

BACKGROUND: While first generation H1-receptor antagonists are widely used, there are relatively few data describing their comparative effects on subjective daytime sleepiness and psychomotor performance. OBJECTIVE: To compare the effects of first generation H1 receptor antagonists on subjective daytime sleepiness and psychomotor performance. METHODS: We conducted two single-dose, cross-over studies. In the first, we validated our methodology in 18 healthy subjects by examining the response to diphenhydramine (50 mg), terfenadine (60 mg), and placebo. In the second trial, we evaluated the relative effects following diphenhydramine (50 mg), diphenhydramine (25 mg), chlorpheniramine (4 mg), and placebo. Psychomotor tests included choice reaction time, hand steadiness, and a test that divided attention between tracking and reaction time. Introspective drowsiness was measured using a visual analog scale and the Stanford Sleepiness Scale. Assessments were made prior to dosing and at one, three, and five hours after dosing; a 7-hour post-drug assessment was included in the second trial. RESULTS: In the first trial, 50 mg diphenhydramine produced significant impairment relative to placebo in both subjective and objective assessments (P < .05). Responses following terfenadine did not differ from placebo. In the second study, all three regimens produced subjective and objective soporific effects to a significantly greater degree than placebo. For example, significant introspective sleepiness was noted three hours following all three regimens (P < .05) and slower choice reaction times were noted one and three hours after dosing (P < .05). The general rank order of effects was diphenhydramine (50 mg), followed by diphenhydramine (25 mg), followed by chlorpheniramine (4 mg). Significant differences among the three regimens were, for the most part, confined to greater soporific effects from diphenhydramine relative to chlorpheniramine (P < .05). CONCLUSIONS: Taken together, our observations confirm that subjective and objective measures of sleepiness and psychomotor performance occur following single doses of diphenhydramine and chlorpheniramine, but not terfenadine. Differences in soporific effects do exist among regimens of first-generation compounds.

Computed tomographic study of the common cold.

BACKGROUND: Colds are common, but the abnormalities they produce in the nasal passages and sinus cavities have not been well defined. METHODS: We studied healthy adult volunteers with self-diagnosed colds of 48 to 96 hours' duration and obtained the following data: information on symptoms, computed tomographic (CT) studies of the nasal passages and sinuses, mucosal-transport times, measures of nasal-airway resistance, and viral-culture studies. Thirty-one subjects (mean age, 24 years) had complete evaluations, including CT scans, which were read without knowledge of the clinical data. An additional 79 subjects underwent the same evaluations, except the CT scans. RESULTS: Of the 31 subjects with CT scans, 24 (77 percent) had occlusion of the ethmoid infundibulum; 27 (87 percent) had abnormalities of one or both maxillary-sinus cavities; 20 (65 percent) had abnormalities of the ethmoid sinuses; 10 (32 percent) had abnormalities of the frontal sinuses; and 12 (39 percent) had abnormalities of the sphenoid sinuses. Infraorbital air cells were present in 14 subjects (45 percent), and pneumatization of the middle turbinate (concha bullosa) was noted in 11 subjects (35 percent). Also common were engorged turbinates (in 7 subjects) and thickening of the walls of the nasal passages (in 13). After two weeks, the CT studies were repeated in 14 subjects, none of whom received antibiotics. In 11 of these subjects (79 percent) the abnormalities of the infundibula and sinuses had cleared or markedly improved. Nasal-airway resistance was abnormal in 29 (94 percent) and mucosal transport in 19 (61 percent) of the 31 subjects who had CT scans. Rhinovirus was detected in nasal secretions from 24 (27 percent) of 90 subjects. CONCLUSIONS: The common cold is associated with frequent and variable anatomical involvement of the upper airways, including occlusion and abnormalities in the sinus cavities.

Therapeutic effects of an anticholinergic-sympathomimetic combination in induced rhinovirus colds.

This study's objective was to determine if the combination of pseudoephedrine hydrochloride and atropine sulfate attenuates the symptomatic and pathophysiologic response of individuals to experimental rhinovirus infection when given after illness begins. Forty-three susceptible adult volunteers were challenged with rhinovirus type 39 and randomly assigned to 1 of 2 treatment groups. Twenty-one subjects were treated with the active medication (0.3 mg atropine sulfate and 60 mg pseudoephedrine) and 22 subjects were treated with inert capsules identical in appearance. Treatments were administered 4 times daily beginning approximately 24 hours after rhinovirus challenge and extending for 5 days. Before challenge and on each of 5 treatment days, all volunteers were asked to rate symptom severity and were evaluated for secretion production (weighted tissues), nasal patency (active posterior rhinomanometry), nasal clearance (dyed saccharin technique), eustachian tube function (9-step test), and middle ear status (tympanometry). Twenty subjects in each group were infected with rhinovirus type 39 and were included in the efficacy analysis. Between-group comparisons showed no significant differences in total symptom scores, combined nasal symptom score, secretion production, or the frequencies of persons with eustachian tube obstruction or abnormal middle ear pressures. However, an objective measure of nasal congestion was significantly lower in the active treatment group. The nasal mucociliary clearance rate was significantly more impaired in that group. Side effects consistent with anticholinergic activity were reported more frequently in the active treatment group.

The effects of phenindamine tartrate on sleepiness and psychomotor performance.

Phenindamine, an H1-receptor antagonist that was developed almost 50 years ago, has been associated with both drowsiness and insomnia. Since its central nervous system profile has not been well characterized, we used a series of psychomotor tests to conduct two studies. In the first, 12 subjects received single oral doses of phenindamine (25 mg), diphenhydramine (50 mg), terfenadine (60 mg), or placebo in a four-way crossover study. Psychomotor tests included choice reaction time (CRT), tracking, and hand steadiness (HS). In the second trial, 15 subjects received single oral doses of phenindamine (25 mg), pseudoephedrine (60 mg), phenindamine and pseudoephedrine, diphenhydramine (50 mg), or placebo in a five-way crossover study. Psychomotor tests included CRT, HS, and a task that divided attention between tracking and reaction time. Introspective drowsiness was measured in both trials with use of a visual analog scale (VAS) and the Stanford Sleepiness Scale (SSS). All assessments were made before and 1, 3, and 5 hours after drug administration. In the first trial, diphenhydramine produced significant impairment relative to placebo (p < 0.05) in CRT, tracking, and HS tasks and higher SSS and VAS scores, with peak effect noted at 3 hours. Phenindamine did not significantly differ from placebo or terfenadine. In the second trial, diphenhydramine produced significant impairment relative to placebo (p < 0.05) in CRT, divided attention, HS, and VAS, and SSS, also peaking at 3 hours. Stanford Sleepiness Scale scores after phenindamine were greater than placebo at 3 hours (p < 0.05) but significantly less than diphenhydramine (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Otologic effects of interferon beta serine in experimental rhinovirus colds.

To evaluate the efficacy and otologic effects of recombinant interferon beta serine for experimental rhinovirus colds, 38 healthy adults received nasal drops of recombinant interferon beta serine, 12 x 10(6) U, or placebo three times daily for 4.3 days beginning 36 hours after infection. Illness rates and severity did not differ between the groups, but the frequency of virus shedding was reduced on the fourth (37% vs 74%) and sixth (11% vs 42%) postchallenge days in recipients of recombinant interferon beta serine. Abnormal eustachian tube function in at least one ear was identified by the inflation-deflation test during 44% of observations in 13 infected recipients of recombinant interferon beta serine compared with 62% of observations in five placebo recipients. Tympanometry revealed middle-ear pressure abnormalities (less than -50 or greater than 20 mm H2O) in at least one ear during 18% of observations in recipients of recombinant interferon beta serine compared with 38% of observations in placebo recipients. These results suggest that antiviral therapy may alter the course of middle-ear dysfunction associated with experimental colds.

Effects of naproxen on experimental rhinovirus colds. A randomized, double-blind, controlled trial.

OBJECTIVE: To determine whether naproxen, a propionic acid inhibitor of cyclooxygenase, alters the course of experimental rhinovirus colds. DESIGN: A randomized, double-blind, controlled trial. SETTING: Rhinovirus challenge model in volunteers cloistered in individual hotel rooms. VOLUNTEERS: Eighty-seven healthy young adults with serum neutralizing antibody titers of less than or equal to 1:2 to the challenge virus; 79 were evaluable. INTERVENTION: Thirty-nine participants received naproxen (loading dose, 400 mg or 500 mg followed by 200 mg or 500 mg three times daily for 5 days). Forty participants received placebo. Treatment was started 6 hours after viral challenge. MEASUREMENTS: Daily measurement of viral titers, symptoms, nasal mucus production, and nasal tissue use; incidence of infection and illness; and measurement of homotypic serum neutralizing antibody responses. RESULTS: Viral titers and serum homotypic antibody responses were similar in the naproxen and placebo groups. Significant reductions in headache, malaise, myalgia, and cough occurred in the naproxen group. A 29% reduction was noted in the total (5-day) symptom score in the naproxen group (95% CI, 16% to 42%). CONCLUSION: Naproxen treatment did not alter virus shedding or serum neutralizing antibody responses in participants with experimental rhinovirus colds, but it had a beneficial effect on the symptoms of headache, malaise, myalgia, and cough. Prostaglandins may be among the inflammatory mediators that play a role in the pathogenesis of rhinovirus colds.

Superficial nasal mucosal blood flow and nasal patency following topical oxymetazoline hydrochloride.

The objective of this study was to evaluate the effect of 60 micrograms oxymetazoline on nasal mucosal blood flow (NMBF) measured by laser Doppler velocimetry. Nasal airflow (measured by anterior rhinomanometry) and subjectively perceived airflow (measured by visual analog scales) were also evaluated. A reduction of NMBF (mL/100 g tissue/min) was observed following local application of 60 micrograms oxymetazoline that was not observed after the vehicle was applied. For example, NMBF at baseline was measured at 78.8 +/- 10.3 mL/100 g tissue/min (mean +/- SEM). During the five minutes following vehicle application, mean values remained at 81.8 +/- 8.8 mL/100 g tissue/min. Five minutes after topical oxymetazoline treatment, NMBF was reduced 49% to 38.3 +/- 10.2 mL/100 g tissue/min. Nasal airflow (mL/sec), which was measured before and after LDV probe placement, was not significantly increased in either the ipsilateral (281.4 +/- 33.1 to 314.3 +/- 31.6) or contralateral nostril (335.7 +/- 26.9 to 262.1 +/- 36.4), probably due to the limited surface application of drug. Subjective assessments of congestion by both the investigator and the subject showed significant improvements in the ipsilateral nostril. We conclude that, under the conditions of our study, localized application of 60 micrograms oxymetazoline significantly reduces superficial nasal blood flow and provides subjectively perceived improvements in nasal stuffiness.

A randomized controlled trial of glucocorticoid prophylaxis against experimental rhinovirus infection.

The effects of combined intranasal and systemic glucocorticoid steroids on the local inflammatory response, and symptoms due to experimental rhinovirus infection were studied in 45 adults randomized to prophylaxis with either placebo or steroids. Intranasal beclomethasone (168 micrograms twice a day) was begun 4 days before viral challenge and continued 5 days after challenge. Oral prednisone (30 mg twice daily) was given for 3 days beginning 1 day before challenge. During the first 48 h after viral inoculation, nasal obstruction, nasal mucus weights, and kinin concentrations in nasal lavages were lower in steroid recipients, but subsequent increases in these variables in the steroid group resulted in no significant cumulative differences between treatment groups. These data suggest that steroid prophylaxis may suppress nasal inflammation and cold symptoms during the first 2 days in experimental rhinovirus colds.

Ineffectiveness of recombinant interferon-beta serine nasal drops for prophylaxis of natural colds.

Two randomized, double-blind, placebo-controlled trials during early autumn of 1986 and 1987 evaluated the efficacy and tolerance of recombinant interferon-beta serine (rIFN-beta ser) nasal drops for prevention of natural rhinovirus colds. In 1986, 9 X 10(6) units of rIFN-beta ser (139 subjects) or placebo (157) were administered once daily except Sundays for 4 w. Rhinovirus colds occurred in 2.8% of rIFN-beta ser recipients and 6.0% of placebo recipients during the treatment period (52% reduction, P = .3). In 1987, 24 X 10(6) units of rIFN-beta ser (186) or placebo (197) were given daily for 25 consecutive days. Rhinovirus colds developed in 6.3% of rIFN-beta ser recipients and 5.3% of placebo recipients. In each study, illness frequency and number of days with subjective colds did not differ between the groups. Recipients of nasal drops of rIFN-beta ser at either dosage did not differ in tolerance from placebo recipients. The lack of both prophylactic efficacy and nasal toxicity are in contrast to prior observations with nasal sprays of rIFN-alpha 2b.

Evaluation of an alpha agonist alone and in combination with a nonsteroidal antiinflammatory agent in the treatment of experimental rhinovirus colds.

The pathogenesis of symptoms of the common cold and their optimal treatment are incompletely understood. To evaluate the role of an oral alpha agonist alone and in combination with a nonsteroidal anti-inflammatory drug in the treatment of experimental rhinovirus colds, 58 subjects were randomized to receive pseudoephedrine 60 mg alone, pseudoephedrine 60 mg plus ibuprofen 200 mg, or placebo, four times daily for 4 1/2 days beginning 30 hours after intranasal rhinovirus inoculation under double-blind conditions. The frequencies of infection, colds occurrence, and viral shedding did not differ significantly between the groups. Total symptom scores were reduced by 59% by pseudoephedrine plus ibuprofen (p less than 0.05) and 48% by pseudoephedrine alone compared with placebo. Nasal symptom scores tended to be lower in recipients of pseudoephedrine plus ibuprofen compared with pseudoephedrine alone (p = 0.09), but other parameters showed no significant treatment differences between the groups. Rhinorrhea, as determined by nasal secretion weights, was significantly reduced in both treatment groups compared to placebo. Nasal patency measurements tended to show the greatest improvement in recipients of pseudoephedrine plus ibuprofen. Therapy was clinically well tolerated. The results suggest that an oral alpha agonist is effective in modifying certain manifestations of experimental rhinovirus infection and that the addition of a nonsteroidal anti-inflammatory drug may provide additional benefit in nasal symptoms and patency. Studies involving large numbers of patients with natural colds are needed to determine the clinical significance of these findings.

Increased noradrenergic metabolism in the cerebellum of the mouse mutant dystonia musculorum.

The neurological mouse mutant dystonia musculorum exhibits bizarre appendicular and truncal dystonia without known cerebellar histopathology. We evaluated striatal dopamine and cerebellar norepinephrine metabolism in this mutant and compared the results with those obtained in wild-type BALB/c and B6C3 controls. Tyrosine hydroxylase activity and dopamine metabolite levels (homovanillic acid and 3,4-dihydroxyphenylacetic acid) in the striatum of the mutant were similar to controls. Tyrosine hydroxylase activity and the steady-state level of 3-methoxy-4-hydroxyphenethyleneglycol, a metabolite of norepinephrine, in the cerebellum were 38% and 42-66%, respectively, greater in the mutant. However, the level of norepinephrine was similar (approximately 350 ng/g). Further, a Purkinje cell-specific marker, cGMP-dependent protein kinase, was unchanged in the mutant and no Purkinje cell pathology was observed with light microscopy. The lack of Purkinje cell derangement and similar levels of cerebellar norepinephrine and cGMP-dependent protein kinase activity suggest that increased norepinephrine metabolism in the cerebellum of this mutant is not a morphological response to gross target cell loss during morphogenesis. The observed changes may be a reaction to abnormal impulse traffic or altered input/output pathways to the mutant cerebellum during its development.

High-affinity [3H]choline accumulation in cultured human skin fibroblasts.

[3H]Choline can be transported across cell membranes by high-affinity (KT less than 5 microM) and low-affinity (KT much greater than 5 microM) systems. High-affinity choline accumulation (HACA) has been demonstrated in synaptosomes made from cholinergic brain regions such as the hippocampus and caudate-putamen. In cell culture, HACA has been demonstrated in glia and avian telencephalon, dissociated spinal cord, and muscle fibroblasts. We examined [3H]choline accumulation in a single normal human fibroblast line cultured from skin biopsy. [3H]Choline accumulation was temperature-dependent and linear with incubation time up to 6 min at 0.125 microM-choline. The apparent KT for [3H]choline was 5 microM, which is similar to that observed in avian fibroblasts. Isoosmotic replacement of Na+ with either Li+ (144 mM) or sucrose (288 mM) severely reduced [3H]choline accumulation (by 70-90%). Pre-incubation with ouabain (100 microM), sodium orthovanadate (100 microM), or 2,4-dinitrophenol (100 microM), or replacement of Ca2+ by Mg2+ had little or no effect on subsequent [3H]choline accumulation. [3H]Choline accumulation was inhibited by hemicholinium-3 (HC-3); after pre-incubation in HC-3 at 37 degrees C for 10 min, the IC50 (at 0.125 microM-choline) was 5.6 microM. The HC-3 sensitivity, Na+ dependence, and low KT suggest that human skin fibroblasts have a high-affinity transport system for choline.

Catechol-O-methyltransferase activity in cultured human skin fibroblasts from controls and patients with dystonia musculorum deformans.

Fibroblasts provide a source of living cells that can be obtained easily from humans and used to evaluate inherited differences in the activities of enzymes important in neurotransmitter and drug metabolism. Here, we describe biochemical characteristics of catechol-O-methyltransferase (COMT, EC 2.1.1.6) activity in homogenates of cultured human skin fibroblasts. Many properties of the enzyme, including apparent affinity for dihydroxybenzoic acid and S-adenosyl methionine, optimal pH and (Mg++), and inhibition by Ca++, are similar to those reported in lysates of human erythrocytes. Culture and assay conditions have been established for optimal and reproducible measurement of COMT activity in individual fibroblast lines. In 16 control lines, COMT activity ranged from 115 to 263 pmol/min/mg protein with a mean of 181 pmol/min/mg protein. Enzyme activity did not vary with the age or sex of the donor. The COMT activities in fibroblasts from eight patients with dystonia musculorum deformans, an inherited movement disorder of unknown etiology, were not significantly different from controls. Monoamine oxidase (MAO, EC 1.4.3.4) type A activity was measured in 12 lines from patients with dystonia, and values did not differ significantly from age- and sex-matched controls. We conclude that inherited variation in activity of these two catabolic enzymes is not sufficient to explain alterations in monoamine metabolism described in this disorder.