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PubMed1987

The effect of indomethacin on the refractory period occurring after the inhalation of ultrasonically nebulized distilled water.

We examined the involvement of inhibitory prostaglandins in refractoriness induced by repeated ultrasonically nebulized distilled water (UNDW) challenge. Six male subjects with asthma who developed both UNDW-induced bronchoconstriction and refractoriness after UNDW were studied on 3 separate days, 1 week apart. On each study day, subjects had an initial UNDW challenge. UNDW responsiveness was assessed with dose-response curves of UNDW volume output versus the percent fall in FEV1. The output provoking a 20% fall in FEV1 (PO20 UNDW) was calculated. FEV1 was measured again at 5-minute intervals until it returned to within 5% of baseline value. UNDW challenge was then repeated. On day 1, the two successive UNDW challenges were performed in absence of any treatment (control day). Before days 2 and 3, subjects received placebo capsules or indomethacin, 100 mg per day, in a double-blind, randomized fashion for 3 days. On both the control and placebo days, repeated UNDW inhalation provoked a significant increase in PO20 UNDW (p less than 0.01), indicating refractoriness. On the indomethacin day, the mean PO20 UNDW during the second UNDW challenge was not significantly different from that obtained during the initial test on that day (p greater than 0.05), indicating that refractoriness did not occur. We suggest that inhibitory prostaglandins are involved in the development of refractoriness after UNDW inhalation.

Adolescent↗

PubMed2005

Botulinum toxin type a for the prophylaxis of chronic daily headache: subgroup analysis of patients not receiving other prophylactic medications: a randomized double-blind, placebo-controlled study.

OBJECTIVE: To assess the efficacy and safety of botulinum toxin type A (BoNT-A; BOTOX, Allergan, Inc., Irvine, CA) for the prophylaxis of headaches in patients with chronic daily headache (CDH) without the confounding factor of concurrent prophylactic medications. BACKGROUND: Several open-label studies and an 11-month, randomized, double-blind, placebo-controlled study suggest that BoNT-A may be an effective therapy for the prophylaxis of headaches in patients with CDH. DESIGN AND METHODS: This was a subgroup analysis of an 11-month, randomized double-blind, placebo-controlled study of BoNT-A for the treatment of adult patients with 16 or more headache days per 30-day periods conducted at 13 North American study centers. All patients had a history of migraine or probable migraine. This analysis involved data for patients who were not receiving concomitant prophylactic headache medication and who constituted 64% of the full study population. Following a 30-day screening period and a 30-day single-blind, placebo injection, eligible patients were injected with BoNT-A or placebo and assessed every 30 days for 9 months The following efficacy measures were analyzed per 30-day periods: change from baseline in number of headache-free days; change from baseline in headache frequency; proportion of patients with at least 30% or at least 50% decrease from baseline in headache frequency; and change from baseline in mean headache severity. Acute medication use was assessed, and adverse events were recorded at each study visit. RESULTS: Of the 355 patients randomized in the study, 228 (64%) were not taking prophylactic medication and were included in this analysis (117 received BoNT-A, 111 received placebo injections). Mean age was 42.4+/-10.90 years; the mean frequency of headaches per 30 days at baseline was 14.1 for the BoNT-A group and 12.9 for the placebo group (P=.205). After two injection sessions, the maximum change in the mean frequency of headaches per 30 days was -7.8 in the BoNT-A group compared with only -4.5 in the placebo group (P=.032), a statistically significant between-group difference of 3.3 headaches. The between-group difference favoring BoNT-A treatment continued to improve to 4.2 headaches after a third injection session (P=.023). In addition, BoNT-A treatment at least halved the frequency of baseline headaches in over 50% of patients after three injection sessions compared to baseline. Statistically significant differences between BoNT-A and placebo were evident for the change from baseline in headache frequency and headache severity for most time points from day 180 through day 270. Only 5 patients (4 patients receiving BoNT-A treatment; 1 patient receiving placebo) discontinued the study due to adverse events and most treatment-related events were transient and mild to moderate in severity. CONCLUSIONS: BoNT-A is an effective and well-tolerated prophylactic treatment in migraine patients with CDH who are not using other prophylactic medications.

Adult↗

PubMed2002

Reduction of nasopharyngeal carriage of Streptococcus pneumoniae after administration of a 9-valent pneumococcal conjugate vaccine to toddlers attending day care centers.

A double-blind, randomized study involving 264 toddlers attending day care centers was conducted to document the effect of a 9-valent pneumococcal conjugate vaccine on the carriage rate of pneumococci. Of 3750 cultures done on nasopharyngeal samples obtained from subjects during a 2-year follow-up period after vaccination, 65% were positive for Streptococcus pneumoniae. In all age windows, the rate of carriage of vaccine-type pneumococci was lower among subjects who received the pneumococcal vaccine than among control subjects, because the acquisition rate was lower in the former group. The effect was most pronounced among subjects aged < or =36 months. The sample size enabled us to study protection against carriage of S. pneumoniae serotypes 6B, 9V, 14, 19F, and 23F; significant protection against all serotypes except 19F was seen in the pneumococcal-vaccine group. The rate of carriage of serotype 6A (not included in the vaccine) was also reduced significantly, but the rate of carriage of serotype 19A (not included in the vaccine) was not. The rate of carriage of non-vaccine-type pneumococci (excluding serotype 6A) was higher in the pneumococcal-vaccine group than in the control group.

Carrier State↗

PubMed2003

Treatment of stable angina with low dose diltiazem in combination with the metabolic agent trimetazidine.

BACKGROUND: The risk/benefit of moderate to high doses of calcium antagonists in stable angina is uncertain. This study investigates the efficacy and acceptability of low dose diltiazem in combination with trimetazidine for the treatment of stable angina. METHODS: In a 28-day, randomized, double blind study, treatment with 90 mg diltiazem in combination with 60 mg trimetazidine or placebo per day was compared in 50 patients with stable angina. The primary outcomes were time to 1-mm ST segment depression and the Duke treadmill score. RESULTS: Of the 25 patients in each treatment group, the number (%) of patients responding to trimetazidine compared to placebo was, in time to 1-mm ST segment depression, 13 (52) versus 5 (20), P<0.05; in the Duke treadmill score, 18 (72) versus 8 (32), P<0.01; and in angina 17 (68) versus 3 (12), P<0.01. Compared to placebo there was an improvement with trimetazidine in mean exercise time to 1-mm ST segment depression of 128 s (95% confidence interval 45.0-208.5; P<0.01); in the mean Duke treadmill score of 57.4% (95% confidence interval 9.9-100; P<0.02); and in mean anginal attacks of 5.1 per week (95% confidence interval, 3.1-7.3, P<0.01). CONCLUSION: The combination of low dose diltiazem with trimetazidine is effective with few side-effects in the symptomatic control of patients with stable angina.

Aged↗

PubMed1995

Alpha sympathomimetic treatment of autonomic insufficiency with orthostatic hypotension.

PURPOSE: In this double-blind study, the authors compared the safety and efficacy of the investigational oral agent midodrine, a specific alpha 1-sympathomimetic agent, with ephedrine, a nonspecific alpha- and beta-adrenergic receptor agonist. Eight patients (4 men and 4 women) with refractory orthostatic hypotension resulting from autonomic failure were studied. This study was based on the notion that neurogenic orthostatic hypotension results from attenuation of adrenergic nerve traffic and not from alpha-adrenergic receptor dysfunction. Although arteriolar vasoconstrictors seem to be appropriate therapeutic agents, their success has been limited, and the search for an ideal drug is ongoing. METHODS: The authors employed a blocked, double-blind, randomized crossover design. The single-blind placebo run-in period was 2 days. The double-blind titration period with either midodrine or ephedrine was 3 to 5 days; the titration end point was to increase standing systolic blood pressure to > or = 80 mm Hg and to maintain a supine pressure below 180/100 mm Hg. The maintenance period was 3 to 5 days. A 4-day placebo washout period was interposed at the crossover point. RESULTS: The ability to stand improved in patients treated with midodrine but not with ephedrine. Midodrine significantly increased both systolic (P < 0.001) and diastolic (P < 0.001) standing blood pressure over placebo (P < 0.001) and ephedrine (P < 0.05). In contrast, ephedrine-induced changes in standing pressures did not significantly differ from placebo (P > 0.05). Midodrine treatment improved the frequency of the ability to stand as compared with ephedrine, and was associated with a significantly higher incidence of standing systolic pressures > 80 mm Hg than was placebo (P < 0.001). Both midodrine and ephedrine significantly increased supine systolic and diastolic blood pressures over placebo (P < 0.001, P < 0.01, P < 0.01, P < 0.01, respectively), but were not significantly different from each other. Ephedrine significantly increased (P < 0.05) the pulse rate as compared with placebo and midodrine, whereas midodrine produced a statistically significant (P < 0.05) but clinically minimal decrease in pulse rate compared with placebo. Neither drug affected clinical laboratory variables. CONCLUSIONS: Midodrine safely and effectively improved orthostatic hypotension caused by autonomic failure. Our data suggest that the ability to stand is improved better by midodrine than by ephedrine.

Adrenergic alpha-Agonists↗

PubMed1993

[Treatment of insomnia related to depressive disorders. Effects of zolpidem versus flunitrazepam administration and withdrawal evaluated in a double-blind study].

The effects of a 15 day treatment with zolpidem (10 mg) and with flunitrazepam (1 mg) on Insomnia Disorders Related to Depressive Disorders (DSM-III-R) have been evaluated on 30 depressive in-patients (mean age 42.3 +/- 9.8). The trial has been carried out on double blind condition after 5 days of single blind placebo administration. Withdrawal effects have been evaluated in single blind condition on a 10 day period after drugs discontinuation. Patient's diagnosis was Major Depression or Dysthymia according to DSM-III-R; inclusion criteria were insomnia (total sleep time < or = 6 h, sleep latency > or = 30 min, wake after sleep onset > or = 30 min, No of awakenings > or = 3) refractory to clomipramine administration at constant dose (75-150 mg/day among patients). Both drugs have been followed by a rapid, significant diminution of insomnia as demonstrated by significant changes at Stanford Sleepiness Scale and Saint Mary Hospital Sleep Questionnaire and by a significant reduction of HDRS total scores. No clinical phenomena of rebound insomnia were detected after zolpidem and flunitrazepam withdrawal. Drug discontinuation however was followed by the slow increase of the score on insomnia items, approximating basal values at the end of the 10 day period after zolpidem and flunitrazepam withdrawal. A parallel increase of HDRS total score was also detected; HDRS changes were mainly due to the increase of the items anxiety somatic, general somatic symptoms, gastrointestinal somatic symptoms, hypochondriasis. The study confirms the therapeutic efficacy of zolpidem and of flunitrazepam in the treatment of insomnia resistant to antidepressant drugs in depressed patients. They also suggest that early drug discontinuation is frequently associated with clinical relapse of insomnia and of several other symptoms correlated with the affective pathology.

Adult↗

PubMed2004

Sleep disturbances in young subjects with visual dysfunction.

PURPOSE: To determine whether the type of ophthalmic disease is predictive of sleep and wakefulness disturbances in young subjects with visual dysfunction. DESIGN: Prospective cohort study. PARTICIPANTS AND CONTROLS: Twenty-five subjects (ages 12-20) were recruited from the Missouri School for the Blind. Twelve controls with normal sight were recruited from a residential school. METHODS: Daily activity was monitored for 14 days using wrist actigraphy. Sleep and wakefulness measures were derived from actigraphy records by automated analysis. Visually impaired subjects were prospectively stratified by presence or absence of optic nerve disease. MAIN OUTCOME MEASURES: Daytime napping and regularity of awakening time (wake-up time instability). RESULTS: Subjects with optic nerve disease napped in the daytime significantly more than other visually impaired children or normal sighted controls: 28.1+/-4.0 minutes per day (mean +/- standard error) versus 11.9+/-2.4 minutes per day in equally visually impaired subjects with intact optic nerve function versus 6.2+/-2.2 minutes per day in subjects with normal sight (P<0.0001). These subjects also showed significantly more variable awakening times than the other groups. Logistic regression revealed that subjects with optic nerve disease are 9.1 times more likely to demonstrate daily napping of more than 20 minutes per day than equally blind subjects without optic nerve disease (95% confidence interval [CI] = 1.4-58.7, P = 0.02). Blind subjects with optic nerve disease are 21.3 times more likely than children with normal sight to nap more than 20 minutes on average per day (95% CI = 1.2-378, P = 0.04). CONCLUSIONS: Optic nerve disease is predictive of increased daytime napping in young visually impaired subjects, suggesting that the nature and presence of ophthalmic disease affect the probability of concomitant sleep timing disorders.

Adolescent↗

PubMed1997

Improved clinical tolerance to chronic lactose ingestion in subjects with lactose intolerance: a placebo effect?

BACKGROUND: Uncontrolled studies of lactose intolerant subjects have shown that symptom severity decreases after chronic lactose consumption. Adaptation of the colonic flora might explain this improvement. AIMS: To compare the effects of regular administration of either lactose or sucrose on clinical tolerance and bacterial adaptation to lactose. METHODS: Forty six lactose intolerant subjects underwent two 50 g lactose challenges on days 1 and 15. Between these days they were given 34 g of lactose or sucrose per day, in a double blind protocol. Stool samples were obtained on days 0 and 14, to measure faecal beta-galactosidase and pH. Symptoms, breath H2 excretion, faecal weight and electrolytes, and orofaecal transit time were assessed. RESULTS: Except for faecal weight, symptoms were significantly milder during the second challenge in both groups, and covariance analysis showed no statistical difference between them. In the lactose group, but not in the sucrose group, faecal beta-galactosidase activity increased, pH dropped, and breath H2 excretion decreased. CONCLUSION: Bacterial adaptation occurred when lactose intolerant subjects ingested lactose for 13 days, and all symptoms except diarrhoea regressed. Clinical improvement was also observed in the control group which displayed no signs of metabolic adaptation. This suggests that improved clinical tolerance may be just a placebo effect.

Adult↗

PubMed2005

A multicenter, randomized, double-blind, retrospective comparison of 5- and 10-day regimens of levofloxacin in a subgroup of patients aged > or =65 years with community-acquired pneumonia.

OBJECTIVE: This subgroup analysis sought to determine the efficacy and tolerability of a 5-day regimen of levofloxacin 750 mg/d compared with a 10-day regimen of levofloxacin 500 mg/d in the treatment of community-acquired pneumonia (CAP) in elderly patients (aged > or =65 years). METHODS: This subgroup analysis was based on the outcomes in patients aged > or =65 years from a randomized, double-blind, controlled trial conducted at 70 US centers. Patients in Pneumonia Severity Index (PSI) class I/II and III/IV were randomized to receive levofloxacin 750 mg/d for 5 days or levofloxacin 500 mg/d for 10 days. Study investigators assessed clinical and microbiologic outcomes 7 to 14 days after administration of the last dose of medication and collected adverse events for 30 days after the last dose. RESULTS: This analysis included 177 elderly patients, 80 receiving levofloxacin 750 mg/d for 5 days and 97 receiving levofloxacin 500 mg/d for 10 days. Although most demographic and baseline clinical characteristics were comparable between the 2 groups, the group that received levofloxacin 500 mg/d was older than the group that received levofloxacin 750 mg/d (median age, 76.0 vs 72.5 years, respectively; P = 0.029) and had a higher mean PSI score (90.7 vs 83.1; P = 0.017). Despite the halved duration of therapy, unadjusted clinical success rates were comparable between the 2 groups (89.0% and 91.9% in the 750- and 500-mg arms, respectively; 95% CI, -7.1 to 12.7). Microbiologic eradication rates were 90.3% (28/31) in the 750-mg arm and 87.5% (14/16) in the 500-mg arm (P = NS). Multivariate analysis adjusting for baseline PSI score indicated that treatment assignment was not statistically associated with clinical success (adjusted odds ratio for clinical success with 500-mg dose, 1.92; 95% CI, 0.62 to 5.99). The incidence of treatment-emergent adverse events did not differ between the 2 study treatments. The most common adverse events in both groups were insomnia, constipation, and headache. CONCLUSIONS: This subgroup analysis found that levofloxacin 750 mg/d for 5 days was well tolerated in the treatment of CAP in elderly patients. Undajusted and adjusted rates of clinical success were statistically similar between levofloxacin 750 mg/d for 5 days and levofloxacin 500 mg/d for 10 days.

Aged↗

PubMed1992

Therapeutic effects and effects on actual driving performance of chronically administered buspirone and diazepam in anxious outpatients.

Two groups of 12 outpatients each (six men and six women) with generalized anxiety disorder, participated in this study. Each patient was treated single-blind with placebo during the first 7 days (baseline), followed by a double-blind drug treatment period of 4 consecutive weeks (active) and ending again with 7 days single-blind placebo treatment (washout). One group received buspirone 5 mg three times a day in the first week and continued with 10 mg in the morning, 5 mg in the afternoon, and 5 mg in the evening during the second, third, and fourth weeks. The other group received diazepam 5 mg three times a day in all 4 weeks. On the evening of the seventh day of each treatment week the Hamilton Rating Scale for Anxiety and the Symptom Check List (90 items) were applied to assess the therapeutic effects, followed by an on-the-road driving test that started 1.5 hours after the last drug or placebo intake. The test consisted of operating an instrumented vehicle over a 100 kilometer highway circuit while attempting to maintain a constant speed and a steady lateral position within the right traffic lane. Two patients in the diazepam group were unable to complete their test after the first and second treatment week, respectively, because of serious sedative reactions. Both buspirone and diazepam were equally effective in reducing overall anxiety symptoms. The specific profiles showed that buspirone also reduced concomitant depressive symptoms and symptoms of interpersonal sensitivity and anger-hostility. In contrast, diazepam was found to be slightly more effective in reducing somatic symptoms and to positively affect sleep disturbances. Moreover, abrupt discontinuation of diazepam resulted in a relapse of psychic anxiety symptoms comparable with the placebo-baseline level and a partial relapse of somatic anxiety symptoms. Chronic treatment with buspirone had no significant effects on lateral position and speed control. In contrast, diazepam significantly impaired control of lateral position in the first 3 weeks of treatment. There was no significant impairment in the fourth treatment week and the placebo-washout week. Speed control was significantly impaired only in the first week. The relevance of the trend toward decreasing performance impairment during chronic treatment remains to be established.

Adolescent↗

PubMed1986

Flurbiprofen versus ASA in influenza symptomatology: a double-blind study.

The effectiveness and safety of flurbiprofen 100 mg b.i.d. vs acetylsalicylic acid (ASA) 500 mg b.i.d. were evaluated in a 4-day double-blind study in 30 patients suffering from influenza. The antipyretic effect of flurbiprofen was similar to that of ASA. Upper and lower respiratory symptoms, gastrointestinal symptoms, articular and muscular pain and asthenia were improved by both drugs. Only one patient on ASA discontinued the treatment.

Adult↗

PubMed1981

Lack of clinical relevance in routine terminal subculturing of blood cultures.

The usefulness of performing final blind subcultures of previously negative blood cultures was evaluated over a 21-month period. From over 14,000 blood culture bottles blindly subcultured after 7 days of incubation, only 12 potentially significant organisms were found. The finding of these 12 organisms did not influence patient care since in 11 instances the same organism had already been reported from prior positive bottles and in 1 instance the patient had already died. These results suggest that blind 7-day subcultures are of minimal value. Other factors that need to be considered before eliminating the final subculture are presented.

Bacteria↗

PubMed2005

Febuxostat, a novel nonpurine selective inhibitor of xanthine oxidase: a twenty-eight-day, multicenter, phase II, randomized, double-blind, placebo-controlled, dose-response clinical trial examining safety and efficacy in patients with gout.

OBJECTIVE: Gout affects approximately 1-2% of the American population. Current options for treating hyperuricemia in chronic gout are limited. The purpose of this study was to assess the safety and efficacy of febuxostat, a nonpurine selective inhibitor of xanthine oxidase, in establishing normal serum urate (sUA) concentrations in gout patients with hyperuricemia (>or=8.0 mg/dl). METHODS: We conducted a phase II, randomized, double-blind, placebo-controlled trial in 153 patients (ages 23-80 years). Subjects received febuxostat (40 mg, 80 mg, 120 mg) or placebo once daily for 28 days and colchicine prophylaxis for 14 days prior to and 14 days after randomization. The primary end point was the proportion of subjects with sUA levels <6.0 mg/dl on day 28. RESULTS: Greater proportions of febuxostat-treated patients than placebo-treated patients achieved an sUA level <6.0 mg/dl at each visit (P < 0.001 for each comparison). The targeted sUA level was attained on day 28 in 0% of those taking placebo and in 56% of those taking 40 mg, 76% taking 80 mg, and 94% taking 120 mg of febuxostat. The mean sUA reduction from baseline to day 28 was 2% in the placebo group and 37% in the 40-mg, 44% in the 80-mg, and 59% in the 120-mg febuxostat groups. Gout flares occurred with similar frequency in the placebo (37%) and 40-mg febuxostat (35%) groups and with increased frequency in the higher dosage febuxostat groups (43% taking 80 mg; 55% taking 120 mg). During colchicine prophylaxis, gout flares occurred less frequently (8-13%). Incidences of treatment-related adverse events were similar in the febuxostat and placebo groups. CONCLUSION: Treatment with febuxostat resulted in a significant reduction of sUA levels at all dosages. Febuxostat therapy was safe and well tolerated.

Adult↗

PubMed2002

Safety and efficacy of an imported fire ant rush immunotherapy protocol with and without prophylactic treatment.

BACKGROUND: Hypersensitivity to the sting of the imported fire ant (IFA) is a growing and significant cause of morbidity and mortality in the United States. Conventional immunotherapy with IFA whole body extract (WBE) has been shown to be effective; however, rush immunotherapy (RIT) with IFA WBE has not been studied. OBJECTIVE: In this study, we evaluated the safety and efficacy of RIT with IFA WBE and sought to determine whether prophylactic pretreatment with antihistamines and steroids reduces the systemic reaction rate associated with RIT. METHODS: Patients with IFA hypersensitivity were randomized to placebo or twice-daily terfenadine 60 mg, ranitidine 150 mg, and prednisone 30 mg initiated 2 days before RIT in a double-blinded study. The 2-day RIT protocol consisted of hourly injections to achieve a final dose of 0.3 mL 1:100 wt/vol. Patients returned on day 8 to receive 2 hourly injections of 0.25 mL 1:100 wt/vol (total, 0.5 mL) and again on day 15 for a single injection of 0.5 mL 1:100 wt/vol. Efficacy of the protocol was determined on day 22, a pair of IFA sting challenges being performed 2 hours apart. RESULTS: Fifty-nine patients were enrolled into the study; a total of 58 patients (age range, 18 to 49 years) initiated the 2-day RIT. Only 3 patients (5.2%) experienced a mild systemic reaction during the protocol. Among those experiencing a systemic reaction with RIT, there was no statistical difference between the 2 premedication groups (3.6% active and 6.7% placebo; P =.87). Sting challenges were performed on 56 patients for a total of 112+ stings; only 1 mild systemic reaction occurred (efficacy, 98.2%). CONCLUSION: RIT with IFA WBE for IFA hypersensitivity is both safe and efficacious; the rate of mild systemic reactions is low. Premedication is not necessary, inasmuch as prophylactic pretreatment with antihistamines and steroids did not reduce the systemic reaction rate associated with RIT.

Adolescent↗

PubMed2000

A new cyclooxygenase-2 inhibitor, rofecoxib (VIOXX), did not alter the antiplatelet effects of low-dose aspirin in healthy volunteers.

The present study examined whether rofecoxib (VIOXX), a new specific inhibitor of cyclooxygenase-2 (COX-2), would interfere with the desired antiplatelet effects of aspirin. Thus, the effects of rofecoxib on inhibition of ex vivo serum-generated thromboxane B2 (TXB2) and platelet aggregation by low doses (81 mg) of aspirin were examined in healthy volunteers. This was a double-blind, randomized, placebo-controlled, parallel study of two treatment groups (n = 12 per group) in which subjects received 50 mg of rofecoxib or placebo for 10 days in a blinded fashion. Subjects also received 81 mg aspirin once on each of days 4 through 10 in an open-label fashion. Blood for measurement of serum TXB2 production and platelet aggregation studies was collected on day 1 (prior to rofecoxib/placebo), on day 4 (prior to aspirin), and on day 10 (before and 4 hours following the seventh dose of aspirin). Platelet-derived serum TXB2 (COX-1 assay) was measured in blood clotted for 1 hour at 37 degrees C. Platelet aggregation was independently induced employing 1 mM arachidonic acid and 1 microgram/mL collagen as agonists. Rofecoxib administered alone had no significant effect on serum TXB2 production or platelet aggregation (day 4). TXB2 production was inhibited 98.4% by aspirin coadministered with either rofecoxib or placebo (day 10). Similarly, platelet aggregation induced by arachidonic acid was inhibited 93.7% and 93.5% by aspirin coadministered with either rofecoxib or placebo, respectively (day 10). The comparable values for inhibition of collagen-induced platelet aggregation were 86.8% and 90.8%, respectively. No important clinical or laboratory adverse experiences were observed. In conclusion, rofecoxib alone (50 mg QD for 4 days) did not inhibit serum TXB2 production or platelet aggregation. In addition, rofecoxib (50 mg QD for 10 days) did not alter the antiplatelet effects of low-dose aspirin (inhibition of platelet aggregation and TXB2 production). Rofecoxib was generally well tolerated when administered alone or in combination with low-dose aspirin.

Adolescent↗

PubMed2003

Effect of montelukast on time-course of exhaled nitric oxide in asthma: influence of LTC4 synthase A(-444)C polymorphism.

Leukotrienes (LT) mediate inflammation in asthma. The fraction of exhaled nitric oxide (FE(NO)) is thought to be a sensitive and reproducible method for assessing airway inflammation in asthmatics and the anti-inflammatory effects of drugs. A number of factors are known to contribute to intrapatient variation in FE(NO) which can confound interpretation. The aims of this study were to characterize the time-course of FE(NO), determine the effect of montelukast on the time-course of FE(NO), and evaluate the influence of the LTC(4) synthase A(-444)C polymorphism on montelukast-evoked changes in FE(NO). Following a 2-week run-in, 7 males and 5 females with asthma, 10-16 years old, received 5 or 10 mg of montelukast or an identical placebo at bedtime for 7 days in double-blind, crossover fashion, followed by a 7-day washout. FE(NO)was quantified every 30 min for 3 or 6 hr at baseline and on days 1, 2, 3, and 7 of treatment. A time-averaged value for FE(NO) was calculated (FE(NO)*), and % changes in FE(NO)* relative to baseline vs. time following placebo and montelukast were compared. The genotype of the A(-444)C polymorphism was determined by PCR and RFLP. FE(NO) varied markedly as a function of time in each patient. Time-averaged values of FE(NO) (FE(NO)*) during placebo and montelukast treatment were similar. Montelukast significantly reduced the slope of the % change in FE(NO)* vs. time curve in heterozygotes (n = 4), but not in A/A homozygotes (n = 8). These data suggest that heterozygotes respond better to montelukast compared to A/A homozygotes, at least with respect to changes in FE(NO). We conclude that assessment of inflammation or the anti-inflammatory effects of drugs in asthma based on single determinations of FE(NO) can be misleading. We further conclude that the A(-444)C polymorphism in the LTC(4) synthase gene probably contributes to interpatient variability in montelukast-evoked changes in FE(NO)* and warrants further study.

Acetates↗

PubMed2003

Clinical features of the retinopathy, globe enlarged (rge) chick phenotype.

The purpose of the study reported here was to characterize the clinical aspects of the autosomal recessive retinopathy, globe enlarged (rge) phenotype in chicks (Gallus gallus). Rge/rge, rge/+ and +/+ chicks were studied from hatch to 336 days of age by general clinical examination, post-mortem examination, vision testing with an optokinetic device, ophthalmoscopy, biomicroscopy, tonometry, central corneal pachymetry, a-mode ultrasonography, infrared photoretinoscopy and photokeratometry. Additionally, preliminary electroretinographic and histopathologic investigations were performed. There is a variable degree of vision loss in rge/rge chicks at 1 day of age with further chicks losing vision over the next few weeks until all chicks become functionally blind by 30 days of age (although some optokinetic responses remain in some of the rge/rge chicks). Over the first few weeks of life rge/rge chicks develop thicker corneas with a larger radius, hyperopia, shallower anterior chambers and enlarged globes both radially and axially, compared to controls. A preliminary ERG study showed that 1 day old rge/rge chicks have an elevated response threshold, a lower amplitude a-wave with a markedly shallow leading slope, a lack of both oscillatory responses and c-waves and, at brighter flashes, an increased b-wave amplitude. Light microscopy revealed no gross retinal abnormalities in young chicks to account for the blindness. A thinning of all retinal layers developed in parallel with globe enlargement. The rge defect is a unique progressive retinal dystrophy that results in a severe visual deficit, abnormal electroretinographic waveforms, and secondary globe enlargement.

Analysis of Variance↗

PubMed1996

Effects of losartan on renal function in patients with essential hypertension.

We examined the renal hemodynamic modifications induced by a selective angiotensin II (AII) AT1 receptor antagonist, losartan, in 10 patients with essential hypertension. In this single-blind study, renal hemodynamic parameters were determined twice (patients were their own controls) first after a 15-day single-blind placebo run-in period and again after a 1-month losartan period. The dosage of losartan was 50 mg/day. Glomerular filtration rate (GFR, inulin clearance), renal plasma flow [RPF; para-aminohippurate (PAH) clearance], microalbuminuria, sodium excretion, proximal sodium tubular reabsorption (lithium clearance), and acid uric metabolism were measured. After 1-month losartan treatment, systolic and diastolic BP (SBP, DBP) decreased significantly throughout the 210-min recording whereas heart rate (HR) was unchanged. GFR (100 +/- 19 vs. 96 +/- 17 ml/min/1.73 m2) and RPF (471 +/- 118 vs. 468 +/- 108 ml/ min/1.73 m2) were not altered by losartan. Rather than occurrence of any modification in filtration fraction (FF), a significant decrease in microalbuminuria was evident (57 +/- 77 vs. 40 +/- 59 mg/24 h, p < 0.05). Urinary sodium excretion was not modified, but an almost significant (p = 0.07) decrease in proximal sodium reabsorption was observed (72.9 +/- 7.7 vs. 68.1 +/- 6.4% of filtered sodium). The increase in renal uric clearance accounted for the significant decrease in serum uric acid (195 +/- 49 vs. 183 +/- 43 microM; p < 0.05). After 1-month losartan treatment, renal function was well preserved; the decrease in uric acid may be of clinical interest when adjuvent diuretic therapy is required.

Albuminuria↗