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Biomedical subjects

V Hartmann

Publications and source records attributed to V Hartmann.

At least 37 records · Page 2Linked to original sources
PubMed1981

[Significance of measurement of the oscillatory resistance to respiration in children. (author's transl)].

The oscillatory resistance to respiration (Ros) was measured in 218 children and 260 adults using the Siregnost FD5 (Siemens, Erlangen), and compared with whole body plethysmography (Raw) and with spirometry. There was a markedly better correlation between Ros and Raw (r=0.82;n=88) in children than in adults (r=0.53;n=260). Whereas additional recording of the phase angle in children does not yield any substantial additional information, it is of diagnostic importance in adults. Comparison of Ros with the spirometric values yielded the following sequence of decreasing correlation coefficients (linear regression): FEV1.0, PEF, V 75, MMEF, V 50, V 25, whereas in adults these relationships cannot be described by means of a linear correlation. The results enable us to conclude that in paediatric pneumology an alternative use of whole-body plethysmography and of oscillatory method appears justified.

Adolescent↗
PubMed1981

Modulation of histamine-induced bronchoconstriction with inhaled, oral, and intravenous clemastine in normal and asthmatic subjects.

Although histamine plays an important role in the pathophysiology of asthma through stimulation of H1 receptors, H1 antagonists are of only limited use in this disease when given orally. In order to investigate the pharmacological response to a specific H1 antagonist administered by different routes, we measured the effect of inhaled clemastine on airway responsiveness to histamine aerosol and compared the results with those after oral and intravenous administration in normal and asthmatic subjects. Inhalation of 0.6 mg clemastine provided significant protection without side effects and was comparable to intravenous administration of 1.0 mg in both groups. In normal subjects 2.0 mg clemastine orally was significantly less effective than the two other routes of administration whereas in asthmatics an enhanced reaction to histamine was observed.

Administration, Oral↗
PubMed1981

Measurement of respiratory mechanics with forced oscillations. Comparison of two methods (Siregnost FD 5 versus a pseudorandom noise technique).

Two methods for measuring respiratory mechanics by forced oscillations were compared, one using a frequency spectrum of 2-32 Hz produced by a pseudorandom noise generator (PRN), the other (Siregnost FD 5) a constant frequency of 10 Hz. In normals and patients with various lung diseases real part of impedance, Re, and phase angle, psi, determined at 10Hz with the two devices correlated well; however, Re measured by Siregnost FD 5 was always higher when compared to PRN. In patients with airway obstruction frequency dependence of resistance and reactance could be shown to be related to the severity of the disease. This important information cannot be obtained by Siregnost FD 5. As Siregnost FD 5 is a simple and reliable method, it is a valuable completion of standard lung function methods. However, for detailed analysis the respiratory system should be investigated at a variety of frequencies.

Airway Resistance↗
PubMed1980

Lung function studies in a patient with diffuse pulmonary fibroleiomyomas.

Diffuse pulmonary fibroleiomyomas were detected by open-lung biopsy in a 33-year-old male patient. Lung function studies revealed severe airflow obstruction, hyperinflation, grossly impaired single-breath-diffusing capacity and a decrease in PaO2 during exercise, i.e. data which are compatible with pulmonary emphysema. However, static lung compliance was within normal limits excluding the existence of pure emphysema. Additional special lung function tests confirmed the assumption that in diffuse fibroleiomyomas of the lung, functional patterns characteristic of obstructive and restrictive lung disease are present that are in agreement with the histological features of this disease.

Adult↗
PubMed1980

[The effect of aminophylline (Euphyllin) on the mechanics of breathing and the gaseous exchange in persons with bronchial asthma (author's transl)].

The physiological effect of intravenous application of aminophylline on the mechanics of breathing and the gaseous exchange in persons with bronchial asthma was studied in 7 out-patients before, during and up to 90 minutes after intravenous injection of 0,48 g of Euphillin, and the data were related to the respective serum levels of the drug. The patients suffered from long-standing bronchial asthma, generally associated with moderate airways obstruction. The bronchodilating effect of Euphyllin could be substantiated for the whole time of the trial solely in respect of the changes in oscillatory impedence; the other parameters showed only temporary changes which had disappeard by the end of the trial although the serum levels of aminophylline were in the therapeutic range (mean +/- SD: 12,5 +/- 3,0 microgram/ml). The data indicate that in some patients with bronchial asthma the effect of Euphyllin on lung function is unpredictable. The suggestion is made to measure the responsiveness of the patient to aminophylline by means of simple lung function tests in order to decide whether or not other bronchodilatory substances should be aded to the therapy.

Adult↗
PubMed1979

[Comparison of the oscillatory measurement of airway resistance with plethysmography and spirometry in juvenile patients].

In 78 children (age 4 to 17 years, height 102 to 179 cm) with and without clinical signs of airway obstruction, spirometric and plethysmographic measurements were compared with the forced oscillation method for determination of resistance to breathing (Ros). Ros was measured with a recently developed apparatus (Siregnost FD5. Siemens) and showed a close correlation with resistance (r = 0.84; n = 78). The spirometric values did not, however, exhibit a definite relationship to Ros. This study demonstrates that airway obstruction in children can be equally well estimated by oscillatory and plethysmographic techniques. Compared with plethysmography, determination of Ros has the particular advantage of being better tolerated by young subjects.

Adolescent↗
PubMed1979

Dco at various breath-holding times: comparison in patients with chronic bronchial asthma and emphysema.

Measurement of Dco is known to be dependent upon functional inhomogeneities. Because different types of inhomogeneities are operative in patients with bronchial asthma and patients with emphysema, different changes of Dco with increasing breath-holding time, tA, are to be expected. We studied the change of Dco with increasing breath-holding time in healthy subjects, patients with asthma bronchiale and patients with emphysema. In the patients the severity of airway obstruction was about the same. The following results were obtained: (a) in healthy subjects and in the asthmatics Dco decreased with tA, in a similar manner, approaching a value (ml . min-1 . Terror-1) of 34.7 and 31.6 at 10 sec, respectively, and (b) in patients with emphysema Dco increased with tA, yielding negative values at small tA: 1.5 sec-23.4; 10 sec: 11.7. From these results we suggest that in healthy subjects and in patients with bronchial asthma parallel inhomogeneities influence the course of Dco. In emphysema the time couse of Dco is best explained with a faster intrapulmonary mixing of He compared to CO. This behavior indicates that in emphysema low Dco values can be mainly attributed to large diffusional resistances (stratification) within the lungs.

Adult↗
PubMed1979

[An experimental and clinical study of the effect of ketotifen in the treatment of extrinsic bronchial asthma (author's transl)].

The therapeutic value of ketotifen (Zaditen), a new anti-allergic drug, was studied in patients with extrinsic bronchial asthma. a) In 8 persons the protective effect on bronchial provocation tests with allergen was examined 3 and 14 days after treatment and compared with cromoglycate (Intal); b) 19 patients were treated for 6 months with 2 x 1 milligram ketotifen (n = 7), 2 x 2 mg ketotifen (n = 7), 2 x 1 mg clemastine (Tavegil) (n = 5). The results were as follows: a) The amount of inhaled allergen causing a fall of 20% in FEV1.0/VC was 9-12 times larger with both therapeutic regimens. b) Ketotifen definitely improved the asthmatic symptoms as compared with clemastine. The improvement was independent of the dosage. Side-effects occurred more frequently with clemastine. The study confirms the in vitro demonstrated anti-analphylactic properties of ketotifen; that it can be taken by mouth is of particular clinical interest.

Asthma↗
PubMed1979

[The value of measurements of oscillatory resistance in the evaluation of lung function. A comparative study in adults and children (author's transl)].

Measurements of total oscillatory impedance (ROS) together with spirometric and body plethysmographic determinations were made in adults and children and the results were compared. In adults (n = 260) correlation was less close (r = 0.53) than it was in 88 children (r = 0.82). Even if ROS was of similar magnitude the phase shift between pressure and flow tended to be more negative than it was in children. These differences are presumably due to anatomical differences between the adult and the growing lung. In interpretation of the results it is suggested that the differences in the ratio: airways compliance/airways resistance reflect changes arising from age and disease processes.

Adolescent↗
PubMed1978

Dihydroergotoxine: separation and determination of four components by high-performance liquid chromatography.

The evaluation of a new high-performance liquid chromatographic method is described. It permits the separation and determination of the four components of dihydroergotoxine (dihydroergocristine, dihydroergocornine, dihydro-alpha-ergocryptine, and dihydro-beta-ergocryptine) in a single step. On reversed-phase microparticles, complete baseline separation is possible with different mobile phases containing about 10(-2) M base. The analysis of dihydroergotoxine mesylate drug substance or its dosage forms can be carried out in about 15 min. No reference substance is required for the determination of the proportions of the components. This method is simple and exhibits high accuracy, reproducibility, and selectivity. It permits the analytical control of dosage forms containing dihydroergotoxine mesylate to ensure that they comply with the specifications for the drug substance used in clinical and pharmacological studies.

Chemical Phenomena↗
PubMed1977

[Stability of liquid ergotalkaloid preparations as a function of the solvent polarity (author's transl)].

The degradation of dihydroergotamine-, dihydroergocornine-, dihydroergocryptine- (both isomers) and dihydroergocristine-mesilate in solution was studied as a function of the temperature and the dielectric constant of the composition. The degradation reactions of the studied hydrogenated ergopeptide alkaloids gave pseudo first-order kinetics. The pseudo first-order rate constants at room temperature were calculated using the Arrhenius equation. It was found that the stability of the studied hydrogenated ergopeptide alkaloids in solution is a function of the dielectric constant of the composition, and that stable solutions can be obtained by the use of water-alcohol mixtures having dielectric constants between 30 and 45. Solutions of the hydrogenated ergot alkaloids in predominantly organic media have the advantage that the degradation to the corresponding aci-forms, hydrolysis products and oxidation products is reduced. For this reason it is not necessary to carry out the filling operation under an inert gas atmosphere in order to protect the hydrogenated ergot alkaloids from oxidation. These results present an important technological advance.

Chemical Phenomena↗
PubMedDate not supplied

Development of a sterilizing in-place application for a production machine using Vaporized Hydrogen Peroxide.

The use of steam in sterilization processes is limited by the implementation of heat-sensitive components inside the machines to be sterilized. Alternative low-temperature sterilization methods need to be found and their suitability evaluated. Vaporized Hydrogen Peroxide (VHP) technology was adapted for a production machine consisting of highly sensitive pressure sensors and thermo-labile air tube systems. This new kind of "cold" surface sterilization, known from the Barrier Isolator Technology, is based on the controlled release of hydrogen peroxide vapour into sealed enclosures. A mobile VHP generator was used to generate the hydrogen peroxide vapour. The unit was combined with the air conduction system of the production machine. Terminal vacuum pumps were installed to distribute the gas within the production machine and for its elimination. In order to control the sterilization process, different physical process monitors were incorporated. The validation of the process was based on biological indicators (Geobacillus stearothermophilus). The Limited Spearman Karber Method (LSKM) was used to statistically evaluate the sterilization process. The results show that it is possible to sterilize surfaces in a complex tube system with the use of gaseous hydrogen peroxide. A total microbial reduction of 6 log units was reached.

Disinfectants↗
PubMedDate not supplied

Brain metastases of an amelanotic melanoma as the primary manifestation in a 15-year old boy.

A 15-year old boy was admitted to hospital with an acute left hemiparesis because of a 3.5 cm-diameter-tumor in the right frontoparietal region. In CCT 4 other tumors were to be seen in both hemispheres after giving contrast medium. Upon a diagnostic operation, a hemorrhage into a metastasis of an amelanotic melanoma was found. The boy survived 2.5 months. In the pathological examination the primary tumor was not found, but there were 12 other intracerebral metastases and two metastases in the left lung and the thyroid gland. Histologically it was an amelanotic melanoma.

Adolescent↗