Mast cell degranulation and parenchymal cell injury in the rat mesentery

OBJECTIVE

The objective of this study was to explore the degree of parenchymal cell injury after mast cell degranulation by application of compound 48/80 (CMP 48/80) in the absence of adherent leukocytes in the rat mesentery.

METHODS

Rats were rendered leukopenic by injection of an antibody against leukocytes, and the mesentery was superfused with CMP 48/80 during intravital microscopy. The extent of cell injury was determined using a fluorescent cell-viability indicator, propidium iodide (PI). In an additional group, mast cell degranulation with CMP 48/80 was prevented by using the mast cell stabilizer Ketotifen.

RESULTS

After a reduction in the number of circulating leukocytes, mast cell degranulation produced a mild increase in parenchymal cell injury. The injury levels significantly increased when individual regions of the mesentery were compared. Stabilization of the mast cells with Ketotifen reduced the injury to below baseline values.

CONCLUSIONS

In the absence of leukocyte adhesion to the endothelium, mast cell degranulation contributes to parenchymal cell injury in the mesentery.

Loratadine: a non-sedating antihistamine. Review of its effects on cognition, psychomotor performance, mood and sedation

Although equally potent at blocking the H1 receptor, first- and second-generation antihistamines can be distinguished with respect to their different effects on the central nervous system (CNS). First-generation antihistamines readily cross the blood-brain barrier leading to significant drowsiness, altered mood, reduced wakefulness, and impaired cognitive and psychomotor performance. This paper reviews of studies CNS functioning conducted with loratadine, a second-generation H1-receptor antagonist, at its therapeutic dose of 10 mg per day. Studies employing self-report measures, such as diary cards, visual analogue scales, rating scales, and mood inventories have shown that the effect of loratadine on somnolence, fatigue, and mood was comparable to those found with placebo. In studies exploring physiological indices of CNS functioning, such as EEG-evoked potentials, and sleep latency tests, loratadine has been shown to be free of CNS effects. In addition, studies have investigated the effects of loratadine on actual driving performance, and on tests of cognitive and psychomotor functioning. On all of these performance measures, loratadine has been shown to have effects comparable to placebo. In contrast, diphenhydramine, a common first-generation antihistamine, usually available without a doctor's prescription, has significant adverse effects on vigilance, divided attention, working memory and psychomotor performance. Impairment has been shown to occur even in the absence of self-reported sleepiness.

A new sample-processing unit for the fluorescent microsphere method

The use of fluorescent-labeled microspheres (FM) for measurement of regional blood flow is an attractive alternative to the use of radioactive-labeled microspheres. In the FM method the FM have to be completely recovered from the tissue samples in a time- and labor-intensive process. For this reason, a considerable loss of FM is possible. The aim of this study was to develop a filtration device that allows the tissue sample to remain in a single container throughout the procedure to make the process easier and to avoid the loss of FM. The core of the sample-processing unit (SPU) is a single-tube filtration device with a polyamide wire mesh. The protocol for processing tissue from different organs (heart, kidney, liver, spleen, intestine, muscle, bone, lung, brain) was modified and thus shortened significantly. Furthermore, the SPU allows direct filtration of the blood reference sample without previous digestion. Different experiments showed that the SPU in combination with the new protocol excludes the loss of 15-micrometers FM. The modifications of the whole procedure render it faster and highly standardized.

Mometasone furoate nasal spray is rapidly effective in the treatment of seasonal allergic rhinitis in an outdoor (park), acute exposure setting

The objective of this study was to determine the time to onset of symptom relief following a single dose of mometasone furoate nasal spray (MFNS) in symptomatic patients with seasonal allergic rhinitis (SAR). This was a single-center, placebo-controlled, double-blind, randomized, parallel-group study with a 7-day run-in period followed by a single-dose administration of medication or placebo in an outdoor park setting. The park site provided an acute exposure to seasonal (tree and grass) pollens. Patients remained in the park of approximately 12 hours after dosing, during which time hourly assessments of SAR symptoms were recorded on a diary card. Two hundred thirty-nine patients with symptoms of SAR entered the study. Patients receiving any concurrent medication for treatment of their symptoms were excluded. Patients were randomized in a 1:1 ratio to receive treatment with either a single dose of MFNS (200 micrograms/or matching placebo nasal spray. Outcome measures included an assessment of overall therapeutic response and change from baseline in total nasal plus non-nasal sign/symptom severity score, total nasal sign/symptom severity score, and total non-nasal sign/symptom severity score. Improvement in total nasal symptom scores, total non-nasal symptom scores, and total nasal plus non-nasal symptom scores were greater and more sustained in patients receiving MFNS than in patients receiving placebo. The mean decrease from baseline in total nasal plus non-nasal symptom scores was significantly greater in MFNS-dosed patients than in placebo-dosed patients at 5 hours after dosing (p < 0.01). The mean decrease from baseline in total nasal symptom scores was significantly greater in MFNS-dosed patients than in placebo-dosed patients at 7 hours after dosing (p < 0.01). The between-treatment differences in total nasal plus non-nasal symptom scores and total nasal symptom scores remained significant for all subsequent hourly assessments through 12 hours post-dose. Patient assessments of overall response to therapy at end point were significantly different between treatment groups (p < 0.01) with 60.5% of MFNS-treated patients reporting complete, marked, or moderate relief compared with 46.5% of placebo-treated patients. Mometasone furoate nasal spray produces a statistically significant improvement in nasal symptom scores in patients with SAR by 7 hours after administration of a single 200 micrograms dose (100 micrograms in each nostril).

Comparison between nasal provocation tests and skin tests in patients treated with loratadine and cetirizine

BACKGROUND

The effect of H1-blockers may differ depending on the target organ.

OBJECTIVE

A double-blind, placebo-controlled study was carried out to compare the effect of a 7-day treatment with loratadine (10 mg daily) or cetirizine (10 mg daily) on nasal challenge with grass pollen grains and skin tests with allergen or histamine.

METHODS

Twenty-four patients were enrolled, but the analysis was carried out on 23. Nasal challenge was carried out by using 5-fold increasing numbers of pollen grains. Skin prick tests were done with serial concentrations of allergens and 1 concentration of histamine. Patients were tested in a cross-over design, with each treatment being administered for the previous 7 days and with a 2-week washout period.

RESULTS

By comparison with placebo, loratadine and cetirizine increased significantly the threshold number of pollen grains required to induce a positive nasal challenge (P <.001). There was no difference between loratadine and cetirizine. Skin test responses to allergen were significantly reduced by loratadine and cetirizine by comparison with placebo. Skin test responses to histamine were significantly decreased by the 2 H1-blockers, but they were more profoundly decreased by cetirizine than by loratadine.

CONCLUSIONS

Both H1-blockers reduced similarly allergen-induced skin test and nasal challenge responses. Cetirizine was more effective on histamine skin test responses.

Allergic rhinitis in Rochester, Minnesota residents with asthma: frequency and impact on health care charges

BACKGROUND

Asthma is a common and costly condition. Concomitant asthma and allergic rhinitis (AR) have been shown to increase the medication costs for people with asthma. No studies have compared medical care costs of those with and without concomitant AR.

OBJECTIVES

We sought to determine the prevalence and incremental medical care costs of concomitant AR.

METHODS

For each member of a population-based asthma cohort, we used all their medical charts within Olmsted County to record age at first diagnosis of asthma; the presence and age of any diagnosis of AR; and the total, ambulatory, and respiratory care-related costs of medical care. Costs were compared for age- and sex-specific strata of people with asthma who did and did not have AR.

RESULTS

AR was most commonly diagnosed in people whose asthma was diagnosed before age 25 (prevalence of 59%) and uncommonly diagnosed in anyone after age 40 (prevalence <15%). Yearly medical care charges were on average 46% higher for those with asthma and concomitant AR than for persons with asthma alone, controlling for age and sex. We were unable to assess the impact of treatment of AR on medical care charges.

CONCLUSIONS

Physicians should consider the diagnosis of AR (prevalence >50%) in all symptomatic children and young adults with asthma. Further evaluation is necessary to evaluate the ability of treatment to decrease the incremental costs of AR in persons with asthma.

Decreased regional blood flow in patients with acromegaly

BACKGROUND AND AIMS

One-third of acromegalic patients have hypertension. Acromegaly is also associated with intrinsic cardiac abnormalities known collectively as a hyperkinetic heart syndrome, which is characterized by an increased cardiac index and decreased systemic vascular resistance. As a result, blood flow should be increased in the regional vascular beds of acromegalic patients. The aim of the study was to measure, using direct methods, blood flow and vascular resistance at the level of the brachial artery in acromegalic patients with a confirmed hyperkinetic heart syndrome.

PATIENTS AND CONTROLS

Twelve patients with active acromegaly (five females, seven males; mean (+/- SD) age, 43 +/- 10 years) were studied. Twelve age- and sex-matched normal subjects served as controls.

METHODS

Right heart catheterization was used to measure the cardiac index and stroke volume and to calculate systemic vascular resistance in the acromegalic patients. Brachial haemodynamics were evaluated with a two-dimensional pulsed Doppler system (double transducer probe and range-gated time system of reception). The mean diameter of the brachial artery and mean blood velocity were measured and used to calculate mean blood flow. Vascular resistance was calculated in the brachial artery as the mean arterial pressure/blood flow ratio.

RESULTS

Age, body weight, height, body surface area and heart rate were similar in the acromegalic patients and controls, while mean arterial pressure was higher in patients. The cardiac index and stroke volume were increased in the acromegalic patients, at 4.08 +/- 0.47 (mean +/- SD) l/min/m2 body surface area and 116.7 +/- 19.4 ml, respectively, while systemic vascular resistance was low (12.5 +/- 2.1 U). Brachial artery diameter was similar in the patients and controls. Brachial artery mean blood velocity (P < 0.01) and mean blood flow (P < 0.05) were lower in the patients than in the controls (3.35 +/- 1.26 vs. 5.12 +/- 1.74 cm/s, and 16.4 +/- 9.4 vs. 25.6 +/- 11.6 ml/min/m2, respectively). The higher mean arterial pressure and lower mean blood flow resulted in higher forearm vascular resistance in the patients than in the controls (132 +/- 61 vs. 83.8 +/- 47 mmHg/ml/s/m2, respectively, P < 0.01).

CONCLUSION

While cardiac output is increased and systemic vascular resistance is decreased in active acromegaly, direct measurement of brachial artery haemodynamics showed lower regional blood flow and increased local resistance relative to healthy controls. These results suggest a heterogeneous distribution of cardiac output in acromegaly.

Hypothalamic-pituitary-adrenal axis suppression and inhaled corticosteroid therapy. 2. Review of the literature

In the first part of this two-part review it was noted that inhaled corticosteroids had become the mainstay of treatment for chronic asthma and yet the effects of long-term use of these compounds on the hypothalamic-adrenal-pituitary (HPA) axis were largely being determined by testing methods of limited reliability, especially by morning plasma cortisol measurements. It was established in our examination of the published literature and in our presentation of current knowledge of the structure and function of the HPA axis that safe, accurate and discriminating techniques to assess the functional status of the HPA axis were available. It was concluded that two state-of-the-art tests that have been insufficiently used were the ACTH stimulation test and measurement of the 24-hour integrated serial plasma cortisol concentrations. These two tests can detect adrenal suppression before the appearance of clinical effects. For part 2 of this review we conducted an exhaustive search of the English language clinical and pharmacological literature on the use of inhaled corticosteroids from 1988 until the present time to identify studies in which one or both of these testing methods have been used. We present our analysis of this limited number of studies to determine what accurately can be known of the HPA axis safety profile of three of the most commonly used and investigated inhaled corticosteroids - beclomethasone dipropionate, budesonide and fluticasone propionate. The first finding of significance was that only 50 reports were identified in which information on the HPA axis safety effects of orally inhaled steroids in asthma patients or in clinical pharmacological studies met our inclusion requirements. By analysis of the data presented in these reports we were able to reach the following conclusions: (1) inhaled corticosteroids administered chronically, and prudently, within recommended dose ranges do not endanger the functioning of the HPA axis, (2) the increasing tendency to use higher doses of inhaled corticosteroids on the assumption that there are clear dose-response benefits and no adverse HPA axis effects from long-term high-dose regimens is misguided and not supported by reliable published information, (3) the corollary - that higher corticosteroid potencies (as measured, for example, by skin-blanching activity) can have greater therapeutic effect in lung tissue without greater concomitant systemic activity - is a flawed concept, and (4) the limited clinical and pharmacological data support our part 1 conclusions that discriminating techniques to assess the functional HPA axis status should be an integral part of the drug development process and that further HPA axis function studies are required on existing inhaled corticosteroids - if they lack a rigorous testing history or long-term record of clinical safety.

Plasma cortisol responses after intramuscular corticotropin 1-24 in healthy men

Intravenous infusion of corticotropin 1-24 (ACTH 1-24) followed by a plasma cortisol measurement after 60 minutes of less than 20 microg/dL indicates clinically important glucocorticoid deficiency. In this study, we evaluated the morning plasma cortisol response to an intramuscular (IM) injection of ACTH 1-24 (250 microg) in 64 healthy men. Plasma cortisol increased significantly 30 and 60 minutes after IM ACTH 1-24 (P < .0001). In most subjects, a maximal response was obtained at 60 minutes. The cortisol response correlated positively with the morning basal cortisol concentration. The lowest cortisol peak and the lowest increment observed after IM ACTH 1-24 were, respectively, 12.6 and 3.5 microg/dL after 30 minutes and 16.3 and 5.3 microg/dL after 60 minutes. We conclude that a plasma cortisol level less than 16.0 microg/dL 60 minutes after IM ACTH 1-24 can be used as an index of glucocorticoid deficiency.

Hypothalamic-pituitary-adrenal axis suppression and inhaled corticosteroid therapy. 1. General principles

The safety of long-term inhaled corticosteroid therapy at commonly prescribed doses is an issue of growing concern to physicians and international regulatory bodies. This is so because long-term use of these drugs has become the mainstay of chronic asthma management and their introduction now is widely recommended in official treatment guidelines at the 'mild persistent' stage of asthma, where regular daily therapy is first begun. In addition to more frequent use of inhaled corticosteroids, there is a further trend to use higher doses of existing inhaler therapies and to use the newer and more potent compounds that have recently become available. At the same time as these developments have been taking place, there has not been a concurrent move to a more rigorous examination of the safety profile of these inhaled corticosteroid treatments - especially to assess their effects on the hypothalamic-pituitary-adrenal (HPA) axis. Most safety data with respect to HPA axis effects have been derived from testing methods that are limited in their ability to detect HPA system impairment and, more seriously, that can give the impression of functional integrity in the HPA axis when there may be moderate (or even greater) impairment. In this first part of a two-part review of the HPA axis effects of inhaled corticosteroids and of how these effects should be assessed, we examine the currently used and the currently available testing methodologies and also review the present state of knowledge concerning the structure and function of the HPA axis and the effects of its suppression. It is clear that there are state-of-the-art tests to assess in a discriminating manner the safety profile of inhaled corticosteroids. These tests have been insufficiently employed, including during the drug development process, yet they are readily available, relatively inexpensive and can detect adrenal suppression before the appearance of clinical effects. In part 2 of this review we examine what can be learned about the effects of inhaled corticosteroid therapy on the HPA axis from the limited amount of reliable published information from clinical and pharmacological studies describing their use and safety.

A comparison of triamcinolone acetonide MDI with a built-in tube extender and beclomethasone dipropionate MDI in adult asthmatics

STUDY OBJECTIVE

In this study, the efficacy and safety of triamcinolone acetonide (TA) metered-dose inhaler with a built-in tube extender and beclomethasone dipropionate (BDP) metered-dose inhaler without a spacer device were compared. Both treatments were dosed at their most commonly used daily doses (within labeling).

DESIGN

A 56-day, randomized, double-blind, double-dummy, placebo-controlled trial.

SETTING

Seventeen asthma/allergy centers.

PATIENTS

We enrolled 339 patients 18 to 65 years of age, with a documented history of bronchial asthma (FEV1, 50 to 90% of predicted value) for > or = 2 years who required inhaled corticosteroid therapy.

INTERVENTIONS

Patients were randomized to receive BDP 336 microg/d (4 puffs bid) plus TA placebo (4 puffs bid), TA 800 microg/d (4 puffs bid) plus BDP placebo (4 puffs bid), or TA and BDP placebos (4 puffs of each bid). The only other asthma medication permitted was inhaled albuterol that was used as a rescue medication. All medications were administered via the closed-mouth inhalation technique.

MEASUREMENTS AND RESULTS

At 8 weeks and at study end point, both active treatment groups had statistically significant and comparable improvements in FEV1 relative to baseline, and statistically significant increases relative to placebo. At study end point, improvements in forced expiratory flow (FEF25.75%), clinic peak expiratory flow (PEFR), and FVC were statistically significant for the active treatment groups compared with placebo. At end point, the mean difference between BDP and TA for mean change in FEV1 from baseline in the efficacy population was 0.02 and the 95% confidence interval was -0.11, 0.15. Asthma symptoms recorded at clinic visits showed statistically significant improvements for the BDP and TA groups compared with the placebo group. Treatment-related adverse events occurred with similar frequency in all patient groups-25.5% of placebo-treated patients, 22.3% of BDP patients, and 20.4% of TA patients. The incidence of oropharyngeal adverse events, including cough, thrush, and dysphonia, was not statistically different between the two active treatment groups.

CONCLUSION

In this randomized, double-blind, placebo-controlled study of adult asthmatics treated with either BDP without a spacer or TA with its built-in tube extender, BDP and TA were comparable in efficacy as measured by FEV1 and other pulmonary function tests, and by improvement in asthma symptoms. Both active treatments were significantly more effective than placebo. All treatment groups were comparable in safety as measured by the incidence of adverse events.

Subjective and objective assessments in patients with seasonal allergic rhinitis: effects of therapy with mometasone furoate nasal spray

BACKGROUND

Efficacy of topical nasal steroid therapy for allergic rhinitis is usually evaluated by patient and clinician assessments of subjective symptom changes in diaries and at clinical interviews.

OBJECTIVE

We sought to complement the subjective measures with objective measures of nasal cytology, biochemistry, and function.

METHODS

In this double-blind, randomized study patients with seasonal allergic rhinitis (SAR) 12 years of age or older received 200 microg mometasone furoate nasal spray (n = 80) or placebo spray (n = 41) once daily for 2 weeks. Subjective assessments by clinician and patient comprised symptom/sign scores and overall therapeutic response evaluations. Objective measures included nasal cytology, nasal biochemistry, nasal airway resistance (NAR), mucociliary clearance, and olfactory functions.

RESULTS

Mometasone furoate produced a significantly greater decrease than placebo in subjective measures of SAR for total symptom score (-46% vs -30%, p < 0.05), total nasal score (-47% vs -30%, p < 0.024), individual nasal symptom scores, and overall therapeutic response. The objective measures of eosinophil, basophil, and neutrophil counts and mucociliary clearance were significantly better in mometasone furoate- than in placebo-treated patients. Similarly, within-treatment statistically significant improvements were produced by mometasone furoate but not by placebo sprays for levels of eosinophilic cationic protein, tryptase and albumin, NAR, and odor identification. Significant positive correlations were found between NAR and nasal stuffiness and between eosinophils, basophils, and neutrophils and both eosinophilic cationic protein and albumin.

CONCLUSION

Subjective measures of SAR were significantly improved in the mometasone furoate group by comparison with placebo-treated patients. Objective assessments supported the subjective findings because within-treatment measures were frequently significantly improved after mometasone furoate treatment but not after placebo treatment.

Impact of dextran on microvascular disturbances and tissue injury following ischemia/reperfusion in striated muscle

The aim of this study was to evaluate the effect of dextran (Dx) 1 versus Dx 60 (molecular weights 1,000 and 60,000) on microvascular disturbances and tissue injury in striated muscle after ischemia/reperfusion (I/R). Experiments were performed using a 4 h pressure-induced ischemia model in the hamster dorsal skinfold chamber. Three groups (n=6) of animals received a continuous infusion (45 min, 3 microL/min) of either Dx 1 or Dx 60 (total dose 5 mg/kg) or saline solution beginning 15 min before reperfusion. Intravital fluorescence microscopy allowed for quantification of functional capillary density, leukocyte adherence, extravasation of fluorescein isothiocyanate-Dx, and nonviable (propidium-positive) cell count before ischemia and .5, 2, and 24 h after reperfusion. Experiments were terminated with tissue preservation for electron microscopy. Postischemic functional capillary density was significantly improved by Dx 60 (at 24 h, 88% vs. 51% in controls). In animals receiving postischemic Dx 1 or Dx 60, leukocyte adherence was significantly reduced (at .5 h, 44% and 58%, respectively) as compared with controls, whereas macromolecular extravasation was unchanged. Nonviable cell count was significantly decreased by both Dx fractions (at 24 h, Dx 1, 75%; Dx 60, 87%), indicating a reduction of tissue injury, which was also confirmed by electron microscopy. These results provide evidence that Dx 60 at 5 mg/kg attenuates I/R injury more effectively than Dx 1. Leukocytes play a major role in the development of I/R injury, but macromolecular extravasation does not always correlate with the leukocyte-endothelium interaction and the manifestation of I/R injury.

Comparative clinical study of inhaled beclomethasone dipropionate and triamcinolone acetonide in persistent asthma

At this time, no placebo-controlled studies in the clinical literature compare the efficacy and safety of the most widely prescribed oral inhaled corticosteroids when dosed at their recommended daily doses. This study compared the efficacy and safety of beclomethasone dipropionate (BDP) 336 microg/day administered by metered dose inhaler (MDI) alone, and triamcinolone acetonide (TA) 800 microg/day by MDI with a built-in tube extender in adults with persistent asthma.

METHODS

This 56-day, randomized, double-blind, double-dummy, placebo-controlled, multicenter trial was conducted in 328 adults with mild to moderately severe asthma (FEV1 50% to 90% of predicted while maintained on inhaled corticosteroids). Patients were seen at a baseline visit and on study days 28 and 56. Efficacy variables included pulmonary function tests, physician and patient assessments of asthma condition, and use of rescue medication.

RESULTS

Statistically significant improvements from baseline in most efficacy measures were demonstrated for both active treatments versus placebo, and with the following exception were the same between active treatments: mean increase in FEV1 in the beclomethasone dipropionate group was statistically significantly greater than in the triamcinolone acetonide group on day 28. Throughout the study, BDP was statistically superior to TA with respect to mean change from baseline in total asthma symptom scores and for 3 of 8 weeks in reducing the mean average weekly use of rescue albuterol (the two active treatments were comparable for this variable at all other time points). Beclomethasone dipropionate and TA were comparable in safety.

CONCLUSION

In adult patients with mild to moderately severe persistent asthma, treatment with BDP consistently conferred greater improvement from baseline in mean FEV1 than TA. This difference achieved statistical significance after 28 days of therapy but was not maintained to endpoint. Decreases in overall asthma symptom scores and in the use of rescue albuterol were statistically significantly greater for the BDP group compared with the TA group. Based on these findings, we conclude that BDP is at least as effective as TA in the treatment of persistent asthma in adults, and judged by some measures, may be superior.

Mechanisms of cell injury in rat mesentery and cremaster muscle

The events responsible for cell injury after a tissue stimulation are only incompletely understood. The purpose of this study was to examine mechanisms of cell injury in two tissues, rat mesentery and cremaster muscle, after tissue stimulation with N-formylmethionyl-leucyl-phenylalanine (FMLP) and platelet-activating factor (PAF). The response was studied in the same animal in random order using normal and leukopenic rats. The tissues were exteriorized after pentobarbital anesthesia. Five to six vascularized areas were chosen in each tissue, and cell injury and hydroperoxide production were assessed visually by continuous superfusion with 1 microM propidium iodide and 5 microM dichlorofluorescin diacetate (DCFH), respectively. FMLP (1 x 10(-8) M) and then PAF (1 x 10(-8) M) were added to the superfusate, and measurements were made at several time points. The second tissue was then examined using the same protocol. In the cremaster, there was little hydroperoxide production, and the tissue injury was eliminated after leukopenia. Leukopenia had no effect on tissue injury in the mesentery. Although hydroperoxide production was observed, there was no correlation between it and the tissue injury. The level of preactivation showed no correlation with either tissue injury or hydroperoxide production. In light of these results, mast cell degranulation may be an important mechanism of tissue injury in the mesentery.

[Oxaceprol reduced leukocyte adhesion and extravasation and preserves perfusion of tissue after ischemia/reperfusion]

The present data indicate that treatment with Oxaceprol results in a significant protection of the microvasculature against I/R injury. The infusion of Oxaceprol during reperfusion leads to a significant reduction in the post-ischemic leukocyte adherence and extravasation as well as an improvement of the nutritive perfusion of the skin muscle. Thus, Oxaceprol treatment would appear to be a promising therapy for the reduction of I/R injury.

Efficacy and safety of loratadine plus pseudoephedrine in patients with seasonal allergic rhinitis and mild asthma

BACKGROUND

Antihistamines have been shown to have a variety of therapeutic effects in asthma. Although nasal obstruction may play an important role in modulating lower airway function, no prior trial has used a decongestant in combination with an antihistamine in patients with allergic rhinitis and concomitant asthma.

OBJECTIVE

We sought to determine the efficacy and safety of loratadine (5 mg) plus pseudoephedrine (120 mg) (L/P) twice daily in patients with seasonal allergic rhinitis and mild asthma.

METHODS

We conducted a randomized, double-blind, placebo-controlled trial of L/P in 193 subjects during the fall allergy season. Nasal and chest symptoms, albuterol use, and peak expiratory flow rates were recorded daily for 6 weeks. Spirometry was measured at baseline and after 1, 2, 4, and 6 weeks of therapy, and health-related quality of life was rated at the beginning and end of the study.

RESULTS

Total rhinitis and asthma symptom severity scores were significantly reduced in patients receiving active therapy compared with those receiving placebo throughout the 6-week study. Peak expiratory flow rates improved significantly in patients treated with L/P during weeks 2 through 6 (peak effect [mean +/- SEM]: L/P, 26.23 +/- 4.64 L/min vs placebo, 8.52 +/- 3.53 L/min, p = 0.002) as did FEV1 (peak effect [mean +/- SEM]: L/P, 170 +/- 53 ml vs placebo, 20 +/- 40 ml, p = 0.01) at all clinic visits. In addition, select measures of asthma-specific quality of life improved significantly relative to placebo.

CONCLUSIONS

L/P significantly improved nasal and asthma symptoms, pulmonary function, and quality of life in patients with seasonal allergic rhinitis and concomitant mild asthma.

Initial and steady-state effects of diphenhydramine and loratadine on sedation, cognition, mood, and psychomotor performance

BACKGROUND

The classic, first-generation histamine1-receptor antagonists used to treat allergic disorders frequently cause sedation. In contrast, sedation is reduced or absent after administration of recommended doses of second-generation histamine1-receptor antagonists. We measured the initial and steady-state effects of diphenhydramine, a first-generation antihistamine, and loratadine, a second-generation antihistamine, by means of a comprehensive battery of psychometric tests that mirror real-world tasks.

METHODS

Healthy volunteers (N = 98) were randomly assigned in a double-blind fashion to receive loratadine (n = 33), diphenhydramine (n = 32), or placebo (n = 33). A computerized test battery was administered at baseline, on day 1 after administration of the initial dose, and on days 3 and 5.

RESULTS

After the initial dose, subjects taking diphenhydramine demonstrated poorer cognitive performance than subjects taking loratadine or placebo on tasks of divided attention, working memory, speed, and vigilance. Subjects taking diphenhydramine also reported greater fatigue and sleepiness and lower levels of motivation, and rated the quality of their performance as lower than subjects taking loratadine or placebo. On day 3, subjects taking diphenhydramine continued to show more fatigue and lower motivation, and rated the quality of their test performance as poorer than subjects taking loratadine or placebo. There were no differences between loratadine and placebo after the initial dose or steady-state (day 5) dosing for any measure of cognitive or psychomotor test performance, mood, or sedation.

CONCLUSIONS

Patients taking diphenhydramine may be at risk of lapses and significant errors that may lead to potential hazards and decreased work productivity.

An improved intravital microscopy system

The use of intravital microscopy as a tool for studying the microcirculation has increased greatly over the last several decades. Early microscopes provided the first pictures of the microcirculation, but were cumbersome to use and subjected the tissue to a high light intensity, a problem which has recently become the subject of much discussion. The goal of this project was therefore to build a more ergodynamic microscope which minimizes the light exposure to the tissue. The automation of the microscope controls provides a platform on which other options can be built into the microscope, such as an autofocus feature. Furthermore, the use of the Optimas software also opens the possibility for on-line data processing.

A prospective multicenter trial of octreotide in 24 patients with visual defects caused by nonfunctioning and gonadotropin-secreting pituitary adenomas. French Multicenter Octreotide Study Group

OBJECTIVE

The somatostatin analog octreotide has been demonstrated to improve optic tract compression caused by pituitary macroadenomas within hours of its administration and/or reduce tumor size in some patients. We report the results of a prospective multicenter study of the effects of octreotide on visual function and tumor size in patients with nonfunctioning pituitary adenomas or gonadotropin-secreting adenomas.

METHODS

Twenty-four patients with visual defects caused by histologically confirmed macroadenomas were administered octreotide via continuous subcutaneous infusion, as follows: 100 micrograms the 1st day and, if necessary, 200 micrograms the 2nd and then 100 or 200 micrograms three times daily if visual function improved. Vision was assessed after 4 days, 1 month, and 2 months, including tumor size evaluation. Visual improvement was defined by a net gain of at least 2/10 in acuity and/or of more than 20% of the surface of one isopter (a reduction in tumor volume of > or = 20% of the initial measurement); opposite changes were defined as deterioration.

RESULTS

Visual improvement was noted in 13 of 24 patients, 10 of 23 patients and 9 of 22 patients, and was not noted in 11 of 24 patients, 14 of 23 patients, and 13 of 22 patients after 4 days, 1 month, and 2 months, respectively. After 2 months, three adenomas had shrunk, three had not changed in size, and one had increased; visual function improved in the seven patients with these adenomas. Octreotide was discontinued in 13 patients for lack of efficacy.

CONCLUSION

The incidence of visual improvement and tumor shrinkage noted in this study was higher than previously reported. Our data suggest that early onset of visual improvement might help in deciding which patients profit from octreotide. However, concomitant gain in visual acuity with deterioration in visual fields or visual improvement with an increase (moderate) in tumor size can occur.

Ischemia and reperfusion in pancreas

Ischemic diseases of heart and brain are the primary causes of mortality in industrialized nations. The ischemic injury with the consecutive reperfusion is responsible for the disturbance of microcirculation with ensuing tissue damage and organ dysfunction. Recent evidence suggests that oxygen-derived free radicals and activated polymorphonuclear leukocytes produced in ischemic tissue are instrumental in the development of ischemic cell injury. In pancreas, ischemia/ reperfusion is proposed as a potentially damaging factor accounting in part for the pathogenesis of acute pancreatitis. Apart from ischemia/reperfusion injury, the kallikrein-kinin system mediates acute inflammation associated with enhanced capillary permeability and accumulation of polymorphonuclear leukocytes, cardinal features of ischemia/reperfusion injury also in acute pancreatitis. Therefore, it seems reasonable to use bradykinin-antagonists to influence postischemic reperfusion injury of the pancreas. In the following, we describe the pathophysiology of ischemia/reperfusion injury with special reference to the pancreatic microcirculation and morphological changes as observed in a model of complete and reversible ischemia. Furthermore, we will discuss the effects of two bradykinin-antagonists (HOE 140 and CP-0597) on functional integrity of the pancreas after ischemia/ reperfusion.

Role of leukocyte plugging and edema in skeletal muscle ischemia-reperfusion injury

The purpose of this study was to examine the relationship of increased capillary network resistance due to leukocyte-capillary plugging and tissue edema through macromolecular leakage to tissue injury after ischemia-reperfusion (I/R). After a 3-h complete ischemia in the dorsal skinfold chamber of the awake Syrian hamster, the following parameters were measured: vessel diameter, macromolecular leakage, erythrocyte velocity, adherent leukocytes, rolling leukocytes, freely flowing leukocytes, functional capillary density (FCD), propidium iodide (PI)-positive cell nuclei, and increase in network flow resistance due to leukocyte-capillary plugging. These measurements were made under baseline conditions and after 0.5 and 2 h of reperfusion for I/R alone, I/R with phalloidin (PL) treatment (to block leakage), and I/R with both PL and cytochalasin D (CD) (to block both leakage and plugging). Neither treatment had an effect on the leukocyte adherence or rolling. PL treatment preserved the endothelial barrier, improved FCD, and reduced the amount of PI measured tissue damage. CD treatment eliminated the increase in network resistance due to leukocyte plugging but did not improve FCD or tissue damage. Thus, in this I/R model, macromolecular leakage plays a role in tissue injury, whereas leukocyte plugging does not appear to be an important mechanism.