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Biomedical subjects

C Bucca

Publications and source records attributed to C Bucca.

At least 73 records · Page 4Linked to original sources
PubMed1990

Hypomagnesemia in chronic obstructive lung disease: effect of therapy.

In 95 patients with severe chronic airway obstruction (FEV1 33.2 +/- 12% of predicted; mean +/- SE), we investigated whether drug therapy had any influence on serum Mg levels. 11/95 patients had a serum Mg less than 1.45 mEq/l (lower normal limit). Multiple-regression analysis showed that the use of diuretics was associated with a significantly lower serum Mg level (1.59 +/- CI 0.06 mEq/l vs. an adjusted mean of 1.71 mEq/l; F = 11, 2, p less than 0.001). There was a significant negative correlation between serum Mg and the length of oral steroid therapy (1.64 +/- CI 0.02 mEq/l for less than 24 months of therapy vs. 1.52 +/- CI 0.06 mEq/l for greater than 24 months of therapy; F = 7, 3, p less than 0.005). No effect of theophylline, inhaled steroids or beta 2-agonists on serum Mg was observed. Because of potential negative effects of hypomagnesemia on respiratory function, routine serum magnesium determination is recommended in patients with chronic obstructive lung disease taking diuretic drugs or corticosteroids.

Administration, Inhalation↗
PubMed1990

Bronchial responsiveness in patients with mitral valve disease.

Bronchial responsiveness has been evaluated in patients with chronic lung congestion secondary to mitral valve disease. Methacholine bronchial challenge was performed by intermittent aerosol generation in 31 patients with mitral valve disease, 18 in New York Heart Association (NYHA) Class II and 13 in NYHA Class III, non-atopic and with baseline forced expiratory volume in one second/vital capacity (FEV1/VC) greater than 85% of predicted and in 30 normal controls. Haemodynamic data were available in 17 patients. The methacholine bronchial provocation dose causing a 35% fall of airway conductance (PD35sGaw) was significantly lower in patients (507 +/- C.I. 205 micrograms) than in normals (2779 +/- C.I. 358 micrograms), (p less than 0.001). In patients log PD35sGaw was significantly correlated with mean pulmonary artery pressure (r = 0.53, p less than 0.05), mean pulmonary capillary wedge pressure (r = 0.67, p less than 0.01), but not with any spirometric parameters. Bronchial hyperresponsiveness seems to be common in patients with mitral valve disease and evidence of lung congestion.

Bronchial Provocation Tests↗
PubMed1989

Hypomagnesemia and bronchial hyperreactivity. A case report.

In a 37-year-old woman, a heavy smoker and an alcoholic, bronchial hyperreactivity to histamine (PC20 FEV1 0.8 mg/ml) was related to hypomagnesemia (0.55 mmol/l). After acute magnesium repletion (24 h i.v. infusion MgSO4 6 g, serum magnesium 1.05 mmol/l), histamine PC20 FEV1 increased up to 9.8 mg/ml. The role of magnesium in modulating smooth muscle contractility is discussed and the importance of checking serum magnesium in patients with airway obstruction is suggested.

Adult↗
PubMed1989

Effect of ascorbic acid on increased bronchial responsiveness during upper airway infection.

We investigated the acute effect of ascorbic acid on histamine bronchial responsiveness (PC 20: concentration causing a 20% fall in FEV1) in 9 hospital staff members with upper respiratory tract infection (URI) and cough. Subjects were examined within 5 days from the start of illness and 6 weeks after. On day 1, the reproducibility of PC20 was assessed by 2 consecutive inhalation challenges 1 h apart; the two values were closely related (r = 0.96, p less than 0.001). Five subjects had bronchial hyperresponsiveness (PC20 less than 8 mg/ml histamine). On the following day, PC20 was measured before and 1 h after oral intake of 2 g ascorbic acid. Vitamin C produced a significant increase in average PC20 (p less than 0.01) from 7.8 +/- (SE) 1.2 to 25.1 +/- (SE) 1.2 mg/ml. None had airway hyperresponsiveness after treatment. Six weeks after the onset of URI, bronchial responsiveness was normal in all the subjects but one. The mean PC20 was 15.5 +/- (SE) 1.25 mg/ml, significantly higher than during URI (p less than 0.05); after ascorbic acid it increased nonsignificantly to 25.7 +/- (SE) 1.35 mg/ml. Our results indicate that vitamin C inhibits the transient increase in bronchial responsiveness occurring in otherwise normal subjects during URI.

Adult↗
PubMed1989

[Negative results of the scintigraphic examination in osteoid osteoma].

The AA. report an unusual case of intraarticular osteoid osteoma of the elbow. Therefore the lesion was strongly suspected; the diagnosis was made only one year after the onset of symptoms by the use of Tc99m MDP bone scan specifically on the blood-pool image. Two earlier bone scans were made with negative results. Considerations have been made by the AA. on the metabolic behaviour of the tumor as shown by scintigraphic scans.

Adult↗
PubMed1989

[Osteoid osteoma: ultrastructural aspects].

The authors take into consideration the ultrastructural aspects of osteoid osteoma and discuss the cellular and subcellular features of this neoplasm. Special attention is given to functional adaptability, which is specific for this type of cell, related to the degree of development of the neoformation.

Calcaneus↗
PubMed1989

Mucosal oedema and airway hyperreactivity.

Mucosal oedema and airway hyperreactivity are common features of asthma, in which they seem to share a common pathogenesis, i.e. airway inflammation. The relationship between oedema and hyperreactivity has not yet been properly investigated. Some speculations are advanced, based on the available experimental evidence. Mucosal oedema may amplify bronchial responsiveness by increasing epithelial permeability, by altering airway mechanics, or by stimulating neural pathways. On the other hand, bronchoconstriction may contribute to oedema by increasing hydrostatic pressure in postcapillary venules.

Asthma↗
PubMed1989

Effects of vitamin C on airway responsiveness to inhaled histamine in heavy smokers.

Histamine bronchial threshold, the provocation concentration of histamine causing a 25% fall in maximal expiratory flow at 50% of forced vital capacity from the control value (PC25MEF50), was measured in seven heavy smokers and in seven sex- and age-matched nonsmokers before and one hour after ingestion, double-blind, of vitamin C (2 g) or placebo. Smokers had significantly lower baseline values of serum ascorbate, maximal expiratory flow at 50% of forced vital capacity (MEF50) and PC25MEF50: the latter was negatively related to serum ascorbate (r = -0.85; p less than 0.001). Acute treatment with vitamin C produced a significant decrease in PC25MEF50 in smokers (95% confidence limit (CL) from 4.87-3.36 to 2.91-2.01 mg.ml-1; p = 0.017), whilst it had no effect in nonsmokers. A preliminary open study on the effect of prolonged administration of vitamin C (1 g daily) was performed in smokers. One week of treatment produced a further significant decrease in PC25MEF50 (p less than 0.0001). Our results suggest that in heavy smokers histamine bronchial responsiveness may be attenuated by chronic ascorbate deficiency. In these circumstances, acute and short-term treatment with vitamin C may increase the bronchoconstrictive response to inhaled histamine.

Adult↗
PubMed1989

Scintigraphy in osteoid osteoma: problems related to differential diagnosis.

Scintigraphy is currently the most widely used and most reliable diagnostic instrumental test for the diagnosis of osteoid osteoma. Indications for its use are based on two considerations: 1) the need for preoperative confirmation of a suspected diagnosis based on clinical and radiographic findings; 2) the preoperative differential diagnosis from lesions which, either due to site or to atypical features, can mimic osteoid osteoma and are not easily identified. However, the high sensitivity of the test is associated with low specificity. In order to increase the specificity, the authors use angioscintigraphy and illustrate some cases where this method permitted differential diagnosis with other bone lesions that simulate the clinical and radiographic features of osteoid osteoma.

Adolescent↗
PubMed1988

A freeze-fracture study of human bronchial epithelium in normal, bronchitic and asthmatic subjects.

Tight junctions (TJ) play a major role in maintaining the integrity of epithelia. Damage of conducting airway surface epithelium is commonly observed in asthma, and recent data suggest that epithelial cells modulate airway smooth muscle tone by the production of relaxant factor(s). To evaluate the ultrastructure of tight junctions (TJ) in human bronchial epithelium of normal and diseased lung, biopsy samples were obtained by fiberoptic bronchoscopy in three normal healthy subjects, four asthmatic patients with bronchial hyperreactivity to methacholine and one heavy smoker with chronic bronchitis. Specimens were examined by electron microscopy, using both thin sections and freeze-fracture techniques. In normal subjects two types of TJ were identified, based on 27 type I, 23 type II junctional areas. Epithelium from the patient with chronic bronchitis showed extensive mucous metaplasia and only junctions of the second type. Extensive epithelial damage was detected in asthmatic subjects, so that a few TJ could be found. Varying degrees of TJ abnormalities were observed and the possible role of such ultrastructural derangements was discussed.

Adult↗
PubMed1988

Acute effect of intravenous magnesium sulfate on airway obstruction of asthmatic patients.

The bronchodilating effect of magnesium sulfate (MgSO4) was studied in ten asthmatic patients with moderate to severe airway obstruction. Two grams of MgSO4 or saline in double-blind crossover design was administered IV for 20 minutes (0.40 mmol/min) and forced expiratory capacity and forced expiratory volume in one second (FEV1) were studied at intervals. Only at the end of MgSO4 infusion did FEV1 increase significantly (109% of initial values). The bronchodilating effect was short lasting and far less than that observed after salbutamol.

Adult↗
PubMed1988

Dose-related effect of inhaled magnesium sulfate on histamine bronchial challenge in asthmatics.

The effects of various doses of inhaled MgSO4 on the histamine bronchoprovocation test were studied in nine asthmatics in clinical remission (FEV1 greater than 80% of predicted). The minimal effective dose of MgSO4 was 0.20 mmol, which increased the dose of histamine which produced a 20% decrease in control FEV1 (PD20) from 2.88 +/- 1.4 to 5.62 +/- 1.38 mumol, p less than 0.05. A greater increase of histamine PD20 was observed after inhalation of MgSO4 at 0.40 mmol (6.90 +/- 1.6 mumol of histamine, p less than 0.05 in comparison with baseline PD20). The decrease in bronchial hyper-reactivity produced by MgSO4 suggests that it influences smooth muscle contractility and may prove to be clinically important in the treatment of asthma.

Adolescent↗
PubMed1987

[Respiratory functional decline after 5 years in patients with silicosis and asbestosis].

A retrospective study of 561 patients with silicosis and 234 with asbestosis was performed to assess whether lung function decline in five years is related to the type (restrictive or obstructive) and/or to the degree of initial damage. Based on lung function tests, three groups of patients were identified: NC with normal lung function tests, CR with restrictive impairment and CO with airway obstruction. The degree of impairment was classified as mild, moderate and severe. Patients were considered worse if five years later they presented a higher degree of impairment. The prevalence of CR was significantly higher in asbestosis, that of NC and CO in silicosis (p less than 0.01). Among subjects with normal starting lung function, 9% only developed CR or CO 5 years later. The prevalence of subjects with worsened lung function in the CR groups was significantly higher (p less than 0.001) in asbestotics (36%) than in silicotics (14%) and was closely related to starting functional impairment. In the CO group the prevalence of worsened subjects was significantly higher than in CR (p less than 0.001), similar in the two diseases and independent of starting lung impairment.

Adult↗
PubMed1987

Reduction of histamine-induced bronchoconstriction by magnesium in asthmatic subjects.

The effects of inhaled MgSO4 on histamine bronchoprovocation test (BPT) were studied in nine asthmatics in clinical remission (FEV1 greater than 80% of predicted). Patients performed histamine BPT on 2 separate days, one day after saline and the other after MgSO4 inhalation, in a randomized double-blind design. Spirometry and flow/volume curve were recorded on each test day before and 5 min after NaCl or MgSO4. No significant difference was observed in lung function measurements 2 days before and after either NaCl or MgSO4. The dose of histamine which produced a 20% decrease in control FEV1 (PD20FEV1) was significantly increased by aerosolized MgSO4 (from 0.177 +/- 0.036 mg after NaCl to 0.350 +/- 0.085 after MgSO4, P less than 0.05. After MgSO4 the dose-steps of histamine concentration increased two-fold in two subjects and one-fold in five.

Administration, Inhalation↗
PubMed1987

Effect of verapamil on pulmonary function changes induced by fluid overloading in normal subjects.

The acute effects of the intravenous administration of 10 mg verapamil on pulmonary function changes induced by rapid saline infusion were studied in six normal subjects. Rapid intravenous fluid overloading caused on increase of closing volume (from 6.55 +/- 1.74 to 9.53 +/- 1.77%, p less than 0.05). After verapamil, the closing volume did not increase after infusion in three subjects and the mean increase was not significant (7.08 +/- 1.82 to 8.43 +/- 1.86%). These results suggest that the rapid administration of intravenous verapamil blunts respiratory function abnormalities caused by overhydration interstitial lung oedema.

Adult↗
PubMed1987

Magnesium attenuates methacholine-induced bronchoconstriction in asthmatics.

The effects of inhaled MgSO4 on methacholine bronchoprovocation test (BPT) were studied in 16 asthmatics in clinical remission (FEV1 greater than 80% of predicted). The patients performed methacholine BPT on two separate days, one day after saline, the other day after MgSO4 inhalation, in double-blind cross-over design. Spirometry was recorded on each test day before and 5 min after NaCl or MgSO4. Neither NaCl nor MgSO4 was found to have a significant effect on spirometric measurements. A significant inhibition of reactivity to methacholine was observed with an increase in log PD20 FEV1 from 1.31 +/- 0.11 inhalation units after NaCl to 1.56 +/- 0.11 inhalation units after MgSO4 (p less than 0.01). The most attractive hypothesis to explain the latter, is that Mg2+ might interfere with Ca2+ handling in the bronchial smooth muscle cells similar to that shown for other types of smooth muscle.

Adolescent↗