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Biomedical subjects

I Zimmermann

Publications and source records attributed to I Zimmermann.

At least 55 records · Page 3Linked to original sources
PubMed1985

Artificial surfactant in preterm rabbits with and without respiratory distress syndrome: difference of in vitro and in vivo activities.

Sixty-eight rabbit fetuses of 27 days gestation were tracheotomised, artificially ventilated, and their lung mechanics studied in a body-enclosing plethysmograph. The animals were treated by tracheal instillation of natural surfactant concentrate or large unilamellar vesicles containing dipalmitoylphosphatidylcholine:egg phosphatidylglycerol, 9:1. Both preparations were highly surface active in terms of film adsorption and surface tension-lowering potential. Before treatment, the lung mechanics were analysed to indicate the presence of respiratory distress syndrome (RDS). Controls received 0.15 M saline. Differences were found between the in vitro and in vivo activities of both preparations in some animals. In 30 preterm animals with partial lung maturity and without respiratory distress syndrome, no significant effect could be achieved with either the natural or the artificial surfactant. In 38 animals with severe RDS, the tidal volume and compliance increased markedly within 15 min of substitution of both preparations. Compliance increased to 178% of the initial value in ventilated, control animals, to 391% in animals treated with natural, and to 344% in animals treated with artificial surfactant.

Animals↗
PubMed1985

Cell instability in basophil leukocytes of patients with chronic obstructive airway disease.

The histamine release from basophils induced by hypo-osmolarity was investigated in 75 healthy persons and in 43 patients with chronic obstructive airway disease. Leukocyte suspensions were diluted with destilled water in cell/water ratio volumen of 1:1, 1:3, and 1:7. Basophils, sequentially treated with increasing amounts of water, show an activation of the release process. A statistically significant age-dependent hypo-osmolar histamine liberation could be demonstrated. Furthermore, a significant higher cell stability was found for the group of patients.

Adult↗
PubMed1984

Local release of histamine, prostaglandin F2 alpha and thromboxane B2 into the tracheal lumen and its influence on airways reactivity.

The influence of tracheal lavage with ascaris extract (AE) on airway response to acetylcholine (ACH) and histamine (Hi) was investigated in a series of 24 dogs. AE administered to a restricted area of the trachea resulted in a release of various mediators such as Hi, prostaglandin F2 alpha (PGF2 alpha, measured as the metabolite 15-keto-13, 14-dihydro-PGF2 alpha) and thromboxane B2 (TXB2) into the tracheal lumen. This differed from H2O administration which resulted in no increased release of these mediators. The relatively small concentrations of these substances measured in arterial plasma argue for the role of these mediators on a local basis. On the other hand, tracheal lavage with allergen induced changes in airway response to ACH and Hi aerosols which was not observed after tracheal lavage with water. An interaction between this allergen-induced mediator release into the trachea and peripheral airways reactivity could be demonstrated.

Acetylcholine↗
PubMed1984

Properties of Streptomyces phage SLE111.

Phage SLE111 infecting Streptomyces levoris 1331 was morphological different from most actinophages described and yielded very high titres (10(11) p.f.u/ml) after lytic growth. Typical morphological changes of infected hyphae were observed by phase contrast and electron microscopy of ultrathin sections. The double-stranded, linear DNA (44.2 +/- 1.3 kb) was characterized, according to electron microscopic analysis, by absence of cohesive ends, of terminal redundance, and circular permutation. A stem-loop structure containing inverted repeats of about 200 bp was identified by electron microscopy in two alternative positions in the SLE111 genome.

Bacteriophages↗
PubMed1984

Interception of lymphatic drainage by Nd:YAG laser irradiation in rat urinary bladder.

Lymphatic drainage can be demonstrated by colloidal indian ink injection. A small intramural indian ink spot in the bladder dome is separated from the rest of the rat urinary bladder by encircling transmural Neodymium-YAG (Nd:YAG) laser irradiation. In untreated animals there is an ink flow via the lymphatic vessels to the regional lymph nodes within several hours. In treated animals, after laser irradiation, the indian ink remains in the bladder dome and a penetration of the irradiated area cannot be found by macroscopic and histologic examination. Indian ink will be found in the regional lymph nodes after the ninth day of absorption of the coagulation necrosis and recanalisation of the intercepted lymphatics. Evidence for the interception of the lymphatic drainage is demonstrated by the distinctly delayed ink flow and the injected ink's remaining in the irradiated area. From this, we conclude that Nd:YAG laser irradiation is especially suitable for tumor coagulation, since simultaneous interception of lymphatic drainage will inhibit the spreading of tumor cells.

Animals↗
PubMed1984

Effect of histamine, acetylcholine and compound 48/80 on bronchoconstriction and release of eicosanoids in the dog.

The effects of Hi and ACH aerosol and of intravenous infusion of compound 48/80 on bronchoconstriction and plasma levels of Hi, TXB2, KH2PGF2 alpha and KH2PGE2 were investigated in 11 bastard dogs. Administration of Hi and ACH aerosol induced bronchoconstriction accompanied by an increase in the plasma levels of Hi and TXB2. No effect on the plasma levels of KH2PGF2 alpha and KH2PGE2 was detected. Release of endogenous Hi by compound 48/80 induced bronchoconstriction and significant increases in the plasma levels of TXB2 as well as of KH2PGF2 alpha and KH2PGE2. The effects of a second administration of Hi and ACH aerosols after compound 48/80 did not differ qualitatively from the effects of the first aerosol administration. However, quantitatively, the second Hi aerosol induced significantly less bronchoconstriction and TXB2 release. Similarly, effects of the second ACH aerosol tended to be decreased as compared to the first ACH aerosol, although the difference was not significant. The diminished effect of the agonists could be due to receptor desensibilization and/or release of adrenaline, which in turn decreases bronchoconstriction and eicosanoid release.

Acetylcholine↗
PubMed1984

[Bronchoconstrictor reaction pattern of the upper respiratory tract and peripheral bronchial system].

Ascaris suum hypersensitive dogs were exposed to ascaris aerosol, histamine, and acetylcholine at different time intervals separately to the upper part of the airtract and to the lower airways. Before and during the exposure the plasma histamine concentrations were measured. Acetylcholine and histamine delivered at the upper part of the airtract do not cause bronchoconstriction. Histamine diffuses in relatively high amounts through the mucosa of the upper part of the airtract into the arterial plasma. Ascaris extract causes bronchoconstriction from the upper part of the airtract as well as from the lower airways. Histamine possibly changes the diffusibility and the sensitivity of the histamine receptor. The correlation between Edyn during acetylcholine and histamine aerosol inhalation was statistically significant. The bronchoconstrictive reaction pattern caused by challenge of the upper part of the airtract is probably different from this caused by challenge of the lower airways.

Acetylcholine↗
PubMed1984

[Influence of vagus nerve, histamine, prostaglandin and catecholamine on airway obstruction].

In three series of experiments, aerosols of acetylcholine, histamine, and Ascaris were administered in a maximal concentration before and after bilateral vagus transection. Vagotomy induced a clear reduction of the dynamic elastance increase by maintaining a constant breath volume. The persisting reaction of the dynamic elastance after vagotomy depends on the intensity of the reaction before vagus transection. Acetylcholine induced the largest reaction. Changes in epinephrine and norepinephrine were found to be variable, but an increase related to dynamic elastance increase could be assumed. Acetylcholine induced a maximal increase in thromboxane B2, and Ascaris induced preferentially a maximal increase in the prostaglandin F2 alpha metabolite 15-Keto-13, 14-dihydro-PGF2 alpha. Vagotomy showed no influence on changes of thromboxane B2, prostaglandin F2 alpha metabolite, or histamine in arterial plasma. The variability in changes of these metabolites may be the cause of the clinical differences in obstructive airway diseases.

Acetylcholine↗
PubMed1984

Partial sensory denervation of the upper respiratory tract on allergen- and histamine-induced bronchoconstriction.

The influence of partial denervation of the upper part of the respiratory tract on histamine- and antigen-induced bronchoconstriction was investigated in a series of 12 boxer dogs. To achieve this purpose, the superior laryngeal, hypoglossal and glossopharyngeal nerves were sectioned. The prophylactic effect of unilateral transection of these nerves on antigen-induced bronchoconstriction originating in the upper respiratory tract could be demonstrated.

Aerosols↗
PubMed1984

Influence of a minimal surgical transection around the trachea on bronchoconstriction in cats.

The influence of a minimal surgical transection around the trachea on ACH- and allergen-induced bronchoconstriction was studied in a series of 21 cats. A significant smaller bronchoconstriction was observed after surgical transection around the trachea. The trachea isolation itself induced a smaller nonsignificant bronchoconstrictive response. This diminished response of the airways after this surgical intervention assumes an interruption of syncytial connections, which alters the response to bronchoconstricting stimuli of the whole bronchial system. The exact role of these syncytial connections has yet to be clarified.

Acetylcholine↗
PubMed1983

Histamine release into tracheal lumen and bronchial reactivity. Effect of local allergen administration on histamine release and bronchial reactivity.

The influence of tracheal lavage with an allergen on the airway response to bronchial challenge with histamine, acetylcholine, and ascaris extract was investigated in 36 dogs. High histamine concentrations were measured in the tracheal solution after lavage with allergen. This amine, released on the mucosal surface, was observed in only very small concentrations in the circulation. Airway response to acetylcholine inhalation was significantly increased after tracheal lavage with allergen. This hyperreactivity of the lower airways induced by tracheal lavage with an allergen suggests that a reflex mechanism is involved. After histamine inhalation a significantly larger antigen-induced histamine release to tracheal lumen was observed. No influence on airway response was found after tracheal lavage with H2O.

Acetylcholine↗
PubMed1983

Histamine release into tracheal lumen and bronchial reactivity. The histamine liberation of proteolytic enzymes in the tracheal lumen in relation to the bronchomotoric reactivity.

The influence of tracheal lavage in a restricted area, with a proteolytic enzyme (Pronase) on the bronchial response to challenge with ACH and AE was studied in 15 dogs. Histamine concentrations measured in the tracheal liquid after lavage with Pronase were smaller than the values after tracheal lavage with allergen. Airway response to ACH inhalation was significantly increased after tracheal lavage with Pronase. Effects of proteolytic enzymes and allergens on the tracheal wall are compared. Allergens and proteolytic enzymes evidence a different mode of action in increasing reactivity of peripheral airways.

Allergens↗
PubMed1983

Histamine level in bronchial mucus and in blood.

Antigen-induced bronchoconstriction can be brought about by provocation of either the upper or lower airways. Rising plasma histamine concentrations can be measured at the time of an increase in airway resistance and at the onset of bronchoconstriction. Relatively high histamine concentrations can be measured in the mucus from patients with chronic obstructive bronchitis. The arterial plasma concentration of histamine was significantly increased in these patients. Histamine administered to a limited area of the tracheal mucosa can induce an increase in airway sensitivity to acetylcholine, but not to allergen or histamine. The role of histamine release in antigen-induced reflex bronchoconstriction originating from the upper airway is questioned.

Acetylcholine↗