Search PubMed⌕ Search

Biomedical subjects

P Sestini

Publications and source records attributed to P Sestini.

At least 37 records · Page 2Linked to original sources

Inhaled PGE2 prevents aspirin-induced bronchoconstriction and urinary LTE4 excretion in aspirin-sensitive asthma.

Bronchial overproduction of leukotrienes and inhibition of prostaglandin synthesis are involved in the pathogenesis of aspirin-induced asthma. We investigated whether inhaled prostaglandin E2 (PGE2) attenuates the response to bronchial challenge with lysine acetylsalicylate (LASA) and the associated increase in urinary leukotriene E4 (u-LTE4) in seven aspirin-sensitive subjects with asthma. Each subject performed two challenges with a single dose of LASA that caused a decrease in FEV1 of 20% or more in a preliminary test, immediately after inhaling 100 micrograms PGE2 in 4 ml saline or placebo, according to a randomized double-blind protocol. FEV1 was recorded at 30-min intervals for 4 h. u-LTE4 was measured by combined high-performance liquid chromatography enzyme immunoassay at 2-h intervals. After placebo, LASA caused an obstructive reaction in all patients, with a maximum decrease in FEV1 of 35 +/- 5% with respect to baseline. u-LTE4 rose from 911 +/- 261 picograms (pg)/mg creatinine at baseline to a maximum value of 2249 +/- 748 after challenge. Inhaled PGE2 provided almost complete protection in all patients. Baseline u-LTE4 was 883 +/- 243 pg/mg creatinine and did not change significantly during the test, reaching a maximum value of 864 +/- 290 (p < 0.05 versus placebo). These results confirm that PGE2 is highly effective in preventing aspirin-induced asthma and suggest that this effect is mediated by inhibition of sulfidopeptide leukotriene production.

Administration, Inhalation↗

Steroid-sparing effect of inhaled lysine acetylsalicylate and furosemide in high-dose beclomethasone-dependent asthma.

BACKGROUND: Inhaled lysine acetylsalicylate and furosemide exert a mutually potentiating protective activity on experimentally induced bronchoconstriction in asthma. OBJECTIVE: Our purpose was to investigate the clinical effectiveness of combined treatment of asthma with inhaled lysine acetylsalicylate and furosemide. METHODS: We performed a randomized, double-blind, crossover study in nine patients with chronic asthma requiring a high dose (2 mg/day) of inhaled beclomethasone for clinical control. Patients were treated with a combination of 720 mg inhaled lysine acetylsalicylate and 40 mg furosemide twice daily, or with matched placebo in addition to inhaled steroids. The dose of inhaled steroids was reduced by half every 15 days and eventually suspended unless a patient's respiratory condition worsened. RESULTS: During treatment with placebo, all patients had worsening of asthma at dosages of 1 or 0.5 mg/day beclomethasone (mean +/- SE, 833 +/- 83 micrograms/day). During combined treatment complete suspension of inhaled steroids in two patients and reduction to 0.5 to 0.25 mg in the remaining seven patients (mean, 250 +/- 72 micrograms/day) was achieved, with a mean reduction of 71% +/- 7%. Forced expiratory volume in 1 second, weekly peak expiratory flow rate, symptom score, and bronchodilator intake remained significantly better with combined treatment than with placebo. CONCLUSIONS: Treatment with inhaled lysine acetylsalicylate and furosemide allows a considerable sparing of inhaled steroids without significant side effects in patients with severe asthma.

Administration, Inhalation↗

Multimedia presentation of lung sounds as a learning aid for medical students.

New educational technologies might help to compensate for the decrease in time and emphasis dedicated to physical examination in medical training. This may, in particular, be applicable for improving the skills in auscultation of the chest. We investigated whether a multimedia presentation of acoustic and graphic characteristics of lung sounds could improve the learning of pulmonary auscultation by medical students, in comparison with conventional teaching methods. We studied 48 medical students without clinical experience, who had received conventional formal teaching on chest examination. Chest auscultation skills were evaluated using an inaccuracy score for the student's auscultation report on three patients, selected according to a standardized procedure. After a baseline evaluation, 27 students in groups of 5-10, participated in a multimedia seminar on lung sounds during which digitized lung sounds were played and the corresponding time-expanded waveform and frequency spectrum were commented on and displayed on a computer. The remaining 21 students received conventional bedside training, acting as control group. The following week, all the students underwent a second evaluation of chest auscultation skills. No differences in the inaccuracy score were observed between the two groups in the preliminary test. However, in the second postintervention assessment, the inaccuracy score of the students who had followed the seminar (11.2 +/- 1.3 points) was significantly lower than that of the controls (16.6 +/- 1.6 points). The answers to a feedback questionnaire confirmed that the great majority of the students found the association of the acoustic signals with their visual image to be useful for learning and understanding lung sounds.(ABSTRACT TRUNCATED AT 250 WORDS)

Attitude of Health Personnel↗

The efficacy and safety of moguisteine in comparison with codeine phosphate in patients with chronic cough.

We conducted a multicentre, double-blind, parallel group study to compare the clinical efficacy of a new antitussive drug, moguisteine (100 mg t.i.d.), to that of a reference standard, codeine (15 and 30 mg, t.i.d.). Both drugs were given orally for a period of two days. A group of 119 patients (mean age 54 yrs; 61 females and 58 males) with chronic, dry or slightly productive cough, associated with various respiratory disorders (including chronic obstructive pulmonary disease, respiratory malignancies and pulmonary fibrosis) were enrolled at six participating centres. The percentage reduction in the number of morning coughs over a period of 6 h after the first administered dose compared to baseline assessment, was 21% with moguisteine (n = 39), 28% with codeine 15 mg (n = 38), and 29% with codeine 30 mg (n = 36). Differences between treatments were not significant. The percentage reduction in the number of nocturnal coughs per hour, after the last evening dose compared to baseline assessment, was 33, 46 and 52%, respectively. Subjective assessments (patients' visual analogue scale scores of cough frequency, cough intensity and sleep disturbance, and investigators' ranking of cough severity) indicated that there was a similar improvement in cough symptoms in all treatment groups. Adverse events were observed in two patients on moguisteine, three on codeine 15 mg, and five on codeine 30 mg. No event was serious, but discontinuation of treatment was required in two patients on codeine 30 mg. The results of our study suggest that moguisteine 100 mg t.i.d. is safe, and seems to have an antitussive activity similar to that of codeine 15-30 mg t.i.d.

Administration, Oral↗

Time-limited protective effect of inhaled frusemide against aspirin-induced bronchoconstriction in aspirin-sensitive asthmatics.

Inhaled frusemide effectively prevents the bronchial obstructive response to allergens and to a number of nonallergic stimuli. In most of the experimental models in which it has been tested, the protective effect of frusemide has been evaluated for only a short time after administration. In aspirin-sensitive patients, acetylsalicylic acid causes an asthmatic reaction which typically lasts for 2 h or more after exposure. We investigated the presence and duration of the protective effect of inhaled frusemide against the bronchial response to aspirin in sensitive patients, using a specific inhalation challenge with lysine acetylsalicylate (LASA). In the first study, eight subjects with aspirin-asthma underwent two bronchial challenges with a single dose of lysine acetylsalicylate administered through a jet nebulizer, after treatment with 40 mg inhaled frusemide or placebo, according to a randomized, double-blind protocol. Forced expiratory volume in one second (FEV1) was monitored for 120 min after challenge. In the second study in eight patients, the protocol was modified by the use of a dosimeter for delivery of lysine acetylsalicylate, by reducing the dose of lysine acetylsalicylate to avoid intense reactions, and by extending the follow-up to 4 h. In the first study, after placebo, FEV1 gradually decreased, reaching a maximum decrement of 39 +/- 3% at 120min. Inhaled frusemide exerted a significant protection at all time-points, although this activity appeared to decrease with time. In the second study, after placebo, inhaled lysine acetylsalicylate caused a gradual decrease in FEV1, which reached a maximum decrement at 180 min.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation↗

Potentiation of the antireactive, antiasthmatic effect of inhaled furosemide by inhaled lysine acetylsalicylate.

Nonsteroid antiinflammatory drugs interfere with the diuretic activity of furosemide, implying that this effect is at least partially dependent on renal prostaglandin synthesis. To investigate whether prostaglandin production could also modulate the bronchial antireactive activity of this diuretic drug, we investigated the effect of inhaled lysine acetylsalicylate (162 mg) and of furosemide (18 mg), alone and in combination, on the bronchial obstructive response to ultrasonically nebulized water in asthmatic patients. The study was also prompted by the conflicting results obtained in previous studies of oral nonsteroid antiinflammatory drugs. Fifteen asthmatic patients underwent bronchial challenge with a mist of ultrasonically nebulized distilled water at the same time of day on four occasions, 2-4 days apart, 15 min after premedication according to a double-blind, randomized protocol. After placebo, mean PD15 to water mist did not differ from a preliminary test (2.1 +/- 0.2 and 2.5 +/- 0.4 ml, M +/- SE, respectively). After lysine acetylsalicylate, mean PD15 rose to 5.0 +/- 0.7 ml (2.8 +/- 0.6 times higher than placebo); after furosemide, to 9.0 +/- 1.5 ml (4.4 +/- 0.9 times over placebo); and after the two drugs in combination, to 32.2 +/- 5.6 ml (16.3 +/- 3.0 times higher than placebo). Similar results were obtained with inhaled indomethacin, whereas sodium salicylate had no effect. These data indicate that the bronchial antireactive activity of inhaled furosemide is greatly enhanced by inhaled lysine acetylsalicylate through a mechanism which probably involves inhibition of the local synthesis of prostaglandins, and could have therapeutic implications.

Administration, Inhalation↗

Protective effect of inhaled piretanide on the bronchial obstructive response to ultrasonically nebulized H2O. A dose-response study.

Inhaled furosemide prevents the obstructive response to several bronchoconstrictor stimuli in asthma. To verify whether this protective effect is also shared by other loop diuretics, we investigated the effect of inhaled piretanide on the bronchial obstructive response to ultrasonically nebulized distilled water (UNW) in ten patients with moderate, stable asthma. In a randomized, single-blind dose-response study, each subject performed an UNW test immediately after nebulization of different doses of piretanide between 12 and 48 mg or placebo. The effect of a single 40-mg dose of inhaled furosemide was also investigated in six subjects. Piretanide caused a significant, dose-dependent increase in UNW PD20 with respect to placebo, corresponding to 0.6 +/- 0.2 doubling doses (mean +/- SE) after 12 mg, 1.3 +/- 0.2 after 24 mg, and 2.0 +/- 0.2 after 48 mg, and had a remarkable diuretic effect; 40 mg of furosemide increased UNW PD20 by 2.3 +/- 0.3 doubling doses (p < 0.01), but showed only a modest diuretic activity. These data indicate that inhaled piretanide is as effective as furosemide in preventing UNW-induced asthma, and this effect is unrelated to their diuretic potency.

Adult↗

Inhaled loop diuretics as potential new anti-asthmatic drugs.

The observation that changes in bronchial osmolarity can induce bronchoconstriction in asthma inspired the experimental studies which, unexpectedly, revealed that frusemide is an effective bronchoprotective agent against a variety of osmotic and non osmotic stimuli. Although the mechanism of this protective effect is not fully understood, studies in vivo and in vitro suggest that frusemide may inhibit the activation of different cell types induced by bronchoconstrictor stimuli. Other loop diuretics also exert bronchoprotective activity, but frusemide appears to be the more effective bronchoprotective agent of this family, regardless of their diuretic potency and lipid solubility. Despite the relatively large amount of experimental evidence, there is currently little information on the clinical effectiveness of frusemide in asthma and a long-term controlled study is currently in progress. The observations that treatment with a combination of inhaled acetylsalicylate and frusemide results in a markedly increased bronchoprotective effect compared to either drug alone, opens a new perspective in the possible clinical use of these drugs. Preliminary studies suggest that the association of these drugs is well tolerated and may result in a remarkable steroid sparing effect in patients with steroid dependent asthma, for whom a convenient alternative to long-term steroid therapy is not currently available.

Administration, Inhalation↗

Protective activity of inhaled nonsteroidal antiinflammatory drugs on bronchial responsiveness to ultrasonically nebulized water.

Relatively high doses of oral aspirin are needed to afford a significant protective effect against the bronchial obstructive reaction to ultrasonically nebulized distilled water (UNDW) in asthmatic patients. Sodium salicylate at similar doses and indomethacin at normal dose afford no protection. The present study was undertaken to assess the protective activity of these drugs taken by inhalation. Thirteen asthmatic patients performed two UNDW challenges 20 minutes and 24 hours after inhalation of 900 mg lysine acetylsalicylate (L-ASA) or placebo. The volume of UNDW causing a 20% fall in FEV1 (UNDW PD20) was calculated by linear interpolation on the dose-response curve. UNDW response after placebo was not significantly different from the preliminary test (PD20 4.3 +/- 0.7 and 4.1 +/- 04 ml, respectively, mean +/- SE), whereas after L-ASA, UNDW PD20 increased to 17 +/- 2.7 ml (p < 0.01 vs placebo) and remained significantly increased after 24 hours. In another group of 12 patients under the same experimental conditions, an equivalent dose of inhaled sodium salicylate caused no effect. Finally, in a third group of asthmatic patients pretreatment with inhaled indomethacin at two dose levels (6 patients, 25 mg; 10 patients, 50 mg) resulted in a significant dose-related protective effect. These findings indicate that inhaled indomethacin and especially L-ASA exert against UNDW-induced bronchoconstriction a potent protective effect, which appears to be mediated by inhibition of local prostaglandin synthesis in the airways. This fact could have therapeutic implications.

Administration, Inhalation↗

Hyperreactivity and bronchial obstruction.

The main obstructive components in bronchial asthma and chronic obstructive pulmonary disease (COPD) are discussed. It is underscored that bronchospasm plays a significant role also in COPD, and that it merits specific treatment (beta 2-stimulants, antimuscarinics, theophylline) even when, in some cases, obstruction appears to be 'irreversible'. The majority of COPD patients react positively, although to a lower degree than asthmatics, not only to chemical agents (histamine, methacholine), but also to 'osmotic' stimuli, such as ultrasonically nebulized distilled water. Geometric factors seem to be in part responsible for the anomalous response. Considering the potent antireactive activity of bronchodilators (beta 2-stimulants in particular), this finding is a further indication for a regular bronchodilator treatment in COPD. Whether such a therapy serves also to improve the prognosis of COPD in the long run has not yet been established.

Asthma↗

Mast cell/nerve interactions in vitro and in vivo.

In this report, we review the evidence for mast cell/nerve interactions. We believe that the morphologic and functional evidence now strongly support a purposeful and biologically significant interaction between these two cell types. This interaction has physiologic consequences and appears to be able to regulate such local events as chloride ion secretion by epithelial cells of the intestinal and respiratory tracts in experimental models. In this way, the mast cell and nerve may be considered as a functional homeostatic regulatory unit. The extent to which this unit may be involved in maintenance of normal integrity of mucous membranes or other structures, in health and in disease, is not clear at the present and will require considerably more investigation and elucidation. However, the concept of such an interaction is an interesting one and may bring new approaches of a therapeutic and diagnostic nature to bear on some old problems. The observations reviewed in this report that psychologic conditioning may itself cause mucosal mast cell degranulation and mediator release in the rat is significant. We consider that this evidence of central nervous system control of mast cell degranulation is an extension of the idea that mast cells and nerves communicate.

Animals↗

Allergic reactions of rat jejunal mucosa. Ion transport responses to luminal antigen and inflammatory mediators.

This study examined the electrophysiological responses to antigen and to various stimuli in jejunal mucosa from rats sensitized to egg albumin with alum and pertussis adjuvants. Luminal antigen caused an immediate increase in short-circuit current, a measure of net ion transport, which was one of three different patterns. All were inhibited by the chloride channel blocker diphenyl-2-carboxylate, by chloride-free buffer, and by doxantrazole, a mast cell stabilizer. Depending on the pattern, the histamine-1 antagonist diphenhydramine, the 5-hydroxytryptamine-2 antagonist ketanserin, and the cyclooxygenase inhibitor piroxicam also reduced the responses. A neural component was indicated by inhibition of the responses to luminal antigen by the neurotoxin tetrodotoxin and by neonatal capsaicin treatment, which depletes substance P-containing nerves. In the absence of antigen, histamine and substance P caused increases in short-circuit current; the magnitude of these changes was significantly greater in tissues from sensitized animals than in controls. These data suggest that sensitization itself may result in hypersecretory responses to some inflammatory mediator and neurotransmitter substances.

Animals↗

Ion transport in rat tracheal epithelium in vitro. Role of capsaicin-sensitive nerves in allergic reactions.

Tracheas from control rats or rats sensitized to egg albumin (EA) were studied in vitro in Ussing chambers, and changes in short-circuit current (Isc) induced by the addition of antigen or agonists on the mucosal (luminal) side were recorded. Addition of EA (100 micrograms/ml) to tracheas from sensitized but not from control rats caused a slow increase of Isc beginning after 15 to 30 s and maximal at 3 to 4 min. This response was inhibited in the presence of doxantrazole, a mucosal mast-cell-stabilizing agent, but not by sodium cromoglycate. A separate group of rats was treated neonatally with capsaicin to deplete peptide neurotransmitters. Responses to EA were significantly lower in capsaicin-treated, sensitized rats than in untreated, sensitized control littermates. No difference was seen in the level of serum EA-specific IgE in these two groups. In tracheas from untreated rats, addition of substance P, capsaicin, platelet-activating factor, and acetylcholine caused an immediate and marked increase in Isc. Responses to substance P and acetylcholine were unaffected by capsaicin treatment. However, responses to capsaicin itself and also to PAF were reduced. These data indicate that changes of net ion transport across the airway epithelium are early phenomena of local hypersensitivity reactions, and that neurotransmitters such as substance P may play an important role in the control of these phenomena.

Animals↗

Protective effect of inhaled furosemide on allergen-induced early and late asthmatic reactions.

The movement of ions and water across the membranes of bronchial cells is part of the control of the bronchial obstructive response to physical stimuli. In a double-blind, randomized, crossover study, we compared the effect of an aerosol of the loop diuretic furosemide with that of a placebo on the early (within 60 minutes) and late (4 to 12 hours) asthmatic responses to a specific inhaled allergen. We studied 11 subjects with mild allergic asthma, who had both early and late asthmatic responses to a specific inhaled allergen in a preliminary challenge. After placebo administration, the maximal changes (mean +/- SE) from base line in the forced expiratory volume in one second (FEV1) and specific airway resistance were, respectively, a decrease of 35 +/- 4 percent and an increase of 288 +/- 56 percent between 0 and 60 minutes after inhalation of the allergen (early response) and a decrease of 35 +/- 5 percent and an increase of 301 +/- 40 percent between 4 and 12 hours (late response). After furosemide administration (4 ml; 10 mg per milliliter), the early response to inhaled allergen was markedly attenuated in all the subjects, and the late response in all but one. The maximal changes in the FEV1 and specific airway resistance were, respectively, a decrease of 11 +/- 2 percent and an increase of 61 +/- 2 percent between 0 and 60 minutes and a decrease of 20 +/- 4 percent and an increase of 178 +/- 25 percent between 4 and 12 hours (P less than 0.05 for all comparisons). No significant differences were seen in the bronchoconstrictor response to inhaled methacholine after furosemide or placebo administration. We conclude that a furosemide-sensitive mechanism in the airways is involved in the pathogenesis of the reactions of patients with allergic asthma. Whether inhaled furosemide might be useful in the treatment of allergic asthma is uncertain and will require further study.

Adolescent↗

Antigen-induced lung solute clearance in rats is dependent on capsaicin-sensitive nerves.

Chemosensitive sensory nerves have an important effector role in the control of vascular permeability in rat airways after neurogenic inflammation. To investigate whether they also have a role in antigen-induced lung inflammation, we have studied the changes in lung solute clearance (LSC) in sensitized rats after aerosol challenge with allergen and the effect of prior capsaicin-induced denervation on these changes. Sprague-Dawley rats were immunized with egg albumin (EA), using aluminum hydroxide and Bordetella pertussis as adjuvants. After 11 days, the animals were challenged for 5 min with aerosolized EA, and the clearance from the lungs of aerosolized 99mTc diethylenetriamine pentaacetic acid (99mTc-DTPA) over 7.5 min (LSC 7.5) was subsequently measured at various times after challenge as an index of epithelial permeability or integrity. Sensitized animals responded to the challenge with immediate respiratory symptoms and with an increased 99mTc-DTPA clearance rate that was detectable at 20 min (mean +/- SE LSC 7.5: baseline, 6 +/- 1%; 20 min, 17 +/- 3%; p less than 0.05), persisted at 4 h (14 +/- 1%; p less than 0.05), and returned to normal values after 24 h. Unsensitized rats exposed to EA and sensitized rats exposed to PBS or to bovine serum albumin did not show any change. Bronchoalveolar lavage failed to show significant changes of cell populations until 24 h, when an increased presence of lymphocytes, PMN, and eosinophils was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Aerosols↗