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N Maltbaek

Publications and source records attributed to N Maltbaek.

17 recordsLinked to original sources

Quantitative computed tomography and aerosol morphometry in COPD and alpha1-antitrypsin deficiency.

Relative area of emphysema below -910 Hounsfield units (RA-910) and 15th percentile density (PD15) are quantitative computed tomography (CT) parameters used in the diagnosis of emphysema. New concepts for noninvasive diagnosis of emphysema are aerosol-derived airway morphometry, which measures effective airspace dimensions (EAD) and aerosol bolus dispersion (ABD). Quantitative CT, ABD and EAD were compared in 20 smokers with chronic obstructive pulmonary disease (COPD) and 22 patients with alpha1-antitrypsin deficiency (AAD) with a similar degree of airway obstruction and reduced diffusion capacity. In both groups, there was a significant correlation between RA-910 and PD15 and pulmonary function tests (PFTs). A significant correlation was also found between EAD, RA-910 and PD15 in the study population as a whole. Upon separation into two groups, the significance disappeared for the smokers with COPD and strengthened for those with AAD, where EAD correlated significantly with RA-910 and PD15. ABD was similar in the two groups and did not correlate with PFT and quantitative CT in either group. In conclusion, based on quantitative computed tomography and aerosol-derived airway morphometry, emphysema was significantly more severe in patients with alpha1-antitrypsin deficiency compared with patients with usual emphysema, despite similar measures of pulmonary function tests.

Aerosols↗

Short-term reproducibility of computed tomography-based lung density measurements in alpha-1 antitrypsin deficiency and smokers with emphysema.

PURPOSE: To study the short-term reproducibility of lung density measurements by multi-slice computed tomography (CT) using three different radiation doses and three reconstruction algorithms. MATERIAL AND METHODS: Twenty-five patients with smoker's emphysema and 25 patients with alpha1-antitrypsin deficiency underwent 3 scans at 2-week intervals. Low-dose protocol was applied, and images were reconstructed with bone, detail, and soft algorithms. Total lung volume (TLV), 15th percentile density (PD-15), and relative area at -910 Hounsfield units (RA-910) were obtained from the images using Pulmo-CMS software. Reproducibility of PD-15 and RA-910 and the influence of radiation dose, reconstruction algorithm, and type of emphysema were then analysed. RESULTS: The overall coefficient of variation of volume adjusted PD-15 for all combinations of radiation dose and reconstruction algorithm was 3.7%. The overall standard deviation of volume-adjusted RA-910 was 1.7% (corresponding to a coefficient of variation of 6.8%). Radiation dose, reconstruction algorithm, and type of emphysema had no significant influence on the reproducibility of PD-15 and RA-910. However, bone algorithm and very low radiation dose result in overestimation of the extent of emphysema. CONCLUSION: Lung density measurement by CT is a sensitive marker for quantitating both subtypes of emphysema. A CT-protocol with radiation dose down to 16 mAs and soft or detail reconstruction algorithm is recommended.

Absorptiometry, Photon↗

Steroid reversibility test followed by inhaled budesonide or placebo in outpatients with stable chronic obstructive pulmonary disease. The Danish Society of Respiratory Medicine.

The aim of this study was evaluate the predictive value of a 2 week course of prednisolone on the effect of 6 months treatment with inhaled budesonide in patients with stable chronic obstructive pulmonary disease (COPD). Forty patients with stable COPD entered the study, and received prednisolone (37.5 mg o.d.) for 2 weeks. They were subsequently divided into steroid-irreversible and steroid-irreversible, using 15% of baseline as a dividing point. In each group patients were randomized to receive budesonide 400 micrograms b.i.d. or placebo for 6 months. During treatment with prednisolone, three patients dropped out because of side effects. Of the remaining 37, only two patients (5%) were reversible with prednisolone forced expiratory volume in 1s [(FEV1) > 15% of baseline], and among the steroid-irreversible, 26 patients were evaluated after 6 months treatment with either placebo or budesonide. No significant differences in spirometry values, symptoms, or number of exacerbations were found between these two groups. Reversibility with prednisolone is rarely seen in COPD. In outpatients with stable COPD and no signs of asthma or atopy, 2 weeks treatment with prednisolone seems to be of no value in choosing subsequent long-term therapy.

Adolescent↗

The indoor microfungus Trichoderma viride potentiates histamine release from human bronchoalveolar cells.

Trichoderma viride (Tv) is often found in damp and mouldy buildings where people complain of adverse health effects including mucosal/respiratory symptoms. Inhaled spores can reach the alveoli and may interact with the airway epithelium. An interaction with the mucosal mast cells was studied in cells obtained by bronchoalveolar lavage (BAL) from 18 individuals. The fungal spores were found to trigger histamine release from the BAL cells, but relatively high concentrations (0.1-2 mg/ml) were needed. A similar dose response was obtained in basophil histamine release. The Tv-induced mediator release was caused by non-immunological (non-IgE-dependent) mechanisms since the histamine release was not changed by removal of IgE from the basophils before exposure of the cells to the spores. However, in very low concentrations (0.1 ng/ml) the fungal spores were found to potentiate IgE-mediated histamine release triggered by anti-IgE antibody in suspensions of BAL cells. Potentiation was also obtained in basophil histamine release, but relatively high concentrations of Tv (10(-2) mg/ ml) were needed. Our in vitro experiments show that mucosal mast cells from the airways are highly sensitive to the potentiating effect of Tv. Although inhalation studies are needed to determine the in vivo effect of the spores, the results suggest reinforcement of mediator release to be a mechanism in the adverse health implications observed in mouldy buildings.

Adult↗

[Theophylline treatment of irreversible, chronic obstructive pulmonary disease].

Even though the clinical efficacy is not well established, theophylline is commonly prescribed as a second or third line drug after inhaled beta 2-agonists and corticosteroids for patients with chronic obstructive pulmonary disease (COPD). The therapeutic index is narrow, and therefore theophylline is often given in a "safe standard dose", e.g. 300 mg b.i.d. We studied the long-term effect of sustained-release theophylline 300 mg b.i.d. over four weeks in 48 patients with severe irreversible COPD (FEV1: 0.99 +/- 0.45 l, FVC: 2.21 +/- 0.68 l) in a randomized, double-blind crossover study. During theophylline treatment there was significant improvements in dyspnoea score (p < 0.001) and morning peak-flow (p < 0.05). In spite of this, there was no significant change in the patients' "sense of well-being" or their daily use of inhaled beta-agonist. Spirometric tests or arterial blood gas values did not change significantly either. It is concluded that addition of theophylline in a "safe standard dose" (i.e. 300 mg b.i.d.) has only limited value in these patients.

Adult↗

Orally administered N-acetylcysteine may improve general well-being in patients with mild chronic bronchitis.

Oral N-acetylcysteine (NAC) exerts a beneficial action in chronic bronchitis by reducing the number of exacerbations. There have been few studies of the effect of NAC (or of any other drug) on general well-being in chronic bronchitis. We used an established psychiatric instrument (General Health Questionnaire; GHQ) and a visual analogue scale (VAS) to measure well-being in a 22-week, placebo-controlled, double-blind, parallel-group study of NAC administered as sustained release tablets 600 mg b.i.d., including during the winter months, to patients with mild chronic bronchitis. One hundred and fifty-three patients were accepted for randomized treatment, 129 finished the study (59 NAC, 70 placebo), and well-being was measured in 105 (46 NAC, 59 placebo). The number of observed exacerbations was unexpectedly low in both groups. The number was lowest in the NAC group, however, the difference did not reach statistical significance in the present study (P = 0.08). There were no statistically significant differences between NAC and placebo in subjective symptom scores, FEV1 or FVC. The distribution of GHQ score at baseline was uneven, but NAC was significantly superior to placebo in terms of a favourable effect on GHQ score. GHQ score correlated with the number of exacerbations, and VAS correlated with GHQ score. This study therefore demonstrates the validity of measuring general well-being in patients with mild chronic bronchitis. Future studies of the treatment of chronic bronchitis should use a battery of more specifically adapted instruments which are now becoming available to measure well-being.

Acetylcysteine↗

N-acetylcysteine by metered dose inhaler in the treatment of chronic bronchitis: a multi-centre study.

Sixty-five patients with chronic bronchitis were studied at five different centres in a double-blind, randomized trial. Two parallel groups were treated with either N-acetylcysteine or placebo by metered dose inhalers for 16 weeks. Following a 1-week run-in period, each patient recorded subjective impressions of the drug action on their bronchitic symptoms in a diary once a week. In addition, exacerbations were registered. Lung function testing and adverse effects were evaluated by four visits to the chest clinics during the 16 weeks. We could not demonstrate that N-acetylcysteine by metered dose inhalers had any significant effect on patients' feeling of well-being, sensation of dyspnoea, intensity of coughing, mucus production, or expectoration or lung function. Its effect in reducing exacerbations could not be estimated because of a very low number of exacerbations reported. N-acetylcysteine inhalation was safe when used over a 16-week period.

Acetylcysteine↗

[AIDS and dementia].

Two case histories are presented of patients with AIDS. In both cases, the initial symptom, apart from the generalized symptoms, was rapidly progressive dementia. The most important neurological symptoms in the AIDS dementia complex are reviewed and the CNS complications of AIDS are mentioned. In patients with atypical neurological clinical pictures, the diagnosis of AIDS should be considered.

AIDS Dementia Complex↗

[Peroral terbutaline in the treatment of patients with severe irreversible obstructive pulmonary disease].

This investigation assesses the effect of oral terbutaline in doses of 7.5 mg twice daily as compared with placebo in patients with moderate to severe chronic airflow limitation (CAL) without reversibility. Seventeen patients completed this double-blind randomised cross-over trial. Diaries with reports of dyspnoea during activities of daily living and peak-flow measurements, were obtained. Measurement of pulmonary function, walking distance and various scorings of function after treatment for three and five weeks were assessed. The investigation demonstrates that in patients with CAL treatment with terbutaline tablets may lead to improvement of several subjective effect variables although no real improvement in the majority of objective effect variables is observed. In patients with irreversible obstructive reduction of pulmonary function, in whom no other form of treatment can be considered, oral treatment with beta-2-agonists may be attempted. If no effect is obtained, the treatment should be withdrawn after one to two months.

Administration, Oral↗

A dental technician with pulmonary fibrosis: a case of chromium-cobalt alloy pneumoconiosis?

A 45 yr old male developed pulmonary fibrosis after 29 yrs of employment as a dental technician. He subsequently developed adenocarcinoma of the lung. Diffuse interstitial fibrosis was seen using light microscopy. Neutron activation analysis of non-neoplastic lung tissue demonstrated high levels of chromium and cobalt suggesting the possibility of a chromium-cobalt alloy pneumoconiosis.

Biopsy↗

[Steroid response after long-term treatment with oral N-acetylcysteine in patients with chronic obstructive bronchitis].

The significance of long-term treatment with N-acetylcystein (NAC) for the steroid response on pulmonary function and general symptoms was investigated in patients with chronic bronchitis and moderate respiratory obstruction. All of the patients had received preliminary treatment with oral NAC in a dosage of 1,200 mg daily (Mucomyst Retard) or a placebo for 22 weeks in a double-blind design. After the conclusion of the long-term treatment but before the code was revealed, 37 non-allergic patients with irreversible respiratory obstruction participated in a follow-up investigation with 30 mg prednisone daily for 14 days. The peak flow was measured twice daily and the symptoms of bronchitis were registered by completion of 13 visual analogue scales. Pulmonary function was measured by means of spirometry on days 0, 7 and 14, respectively. In both of the treated groups, slight increase in the daily registered peak flow was found but no changes in the results of spirometry or the symptoms. Comparison between the groups revealed a significantly greater increase in the evening peak flow in the group which had received preliminary treatment with NAC. It is concluded that, in this investigation, no clinically relevant effect of long-term preliminary treatment with NAC on the results of a steroid test was observed in patients with chronic bronchitis and moderate respiratory obstruction.

Acetylcysteine↗

Effects of oral terbutaline in chronic airflow limitation.

A randomized, double-blind, crossover study was conducted to assess the efficacy of five weeks' treatment with terbutaline, 15 mg daily, compared with placebo in 17 evaluable patients with moderate to severe chronic airflow limitation (CAL) with a minor reversible component. A significant improvement after terbutaline treatment compared with placebo was observed in subjective assessments of breathlessness after two of the activities of daily living, and in daily peak flow measurements recorded in patient diaries. At the clinical assessment after five weeks' terbutaline therapy, 12 of 17 patients had improved pulmonary symptom scores compared with placebo, and a slight increase in FEV1 was observed relative to placebo (0.09 L, p less than 0.05). Thus, five weeks' treatment with oral terbutaline in patients with CAL resulted in significant improvements in several subjective assessments, despite a lack of effect on the majority of the objective variables.

Administration, Oral↗

Small opacities among dental laboratory technicians in Copenhagen.

After a case of advanced pneumoconiosis occurred in a dental laboratory technician, 31 other dental technicians and 30 control subjects controlled for smoking habits, sex, and age were investigated. More technicians (55%) than controls (30%) had at least grade 1 dyspnoea (p greater than 0.05). Multiple regression analysis showed that 13 technicians who had produced dental prostheses for at least 15 years had consistently lower lung function (FVC, FEV1, FEV1/FVC, MEF50, and DCO single breath), although the differences were not statistically significant. All mean lung function values for technicians and controls were within normal limits. Increases in MEF50 after breathing 80% helium and 20% O2 failed to show small airways dysfunction among the technicians. Of the six with radiological pneumoconiosis (5 simple, 1 advanced) four had symptoms. All three biopsy specimens showed varying degrees of pulmonary fibrosis. DCO single breath was diminished in four of the six. One male dental technician had scleroderma and possibly Erasmus syndrome. Blind readings showed an increased number of suspicious chest x rays films (greater than or equal to category 0/1) among older smokers and ex-smokers (p = 0.013) regardless of occupation. Our results support other evidence that dental technicians are at risk of developing pneumoconiosis. Therefore, adequate hygienic control of dental laboratories is indicated.

Adolescent↗

Haemodynamic effects of atenolol, pindolol and propranolol during adrenaline infusion in man.

In a double blind, cross over study the haemodynamic effects of an i.v. infusion of adrenaline during concomitant administration of atenolol, pindolol, propranolol or placebo were examined in 7 healthy volunteers. During coadministration with placebo, adrenaline caused an increase in systolic blood pressure (SBP) of 26 mm Hg and a decrease in diastolic blood pressure (DBP) of 20 mm Hg. Heart rate (HR) and stroke volume (SV) were increased by about 20-30%. Total peripheral resistance (TPR) fell significantly. When the subjects were pretreated with atenolol, the adrenaline increased SBP by 16 mm Hg, the DBP did not change, HR and SV increased by 19 and 30%, and TPR fell. During concomitant administration of the non-selective betablocker pindolol, which has strong intrinsic sympathomimetic activity (ISA), adrenaline increased SBP by 11 mm Hg and DBP by 17 mm Hg. This pure pressor response led to a significant reduction in HR and SV and an increase in TPR, probably mediated through the baroreceptors. The haemodynamic response to adrenaline during coadministration of propranolol was very similar to that seen after pindolol. It is concluded that a beta1-selective blocker interferes very little with the haemodynamic response to adrenaline, whereas it is changed to a pure pressor response during coadministration of a non-selective betablockers. ISA did not significantly modify the pressor response.

Adult↗