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Biomedical subjects

W D Kuhlmann

Publications and source records attributed to W D Kuhlmann.

At least 55 records · Page 3Linked to original sources
PubMed1978

Early atherosclerotic lesions in rat aorta. Effect of cholesterol feeding and immunization.

Germ-free and conventional rats were fed cholesterol or normal pellets and part of both groups were immunized repeatedly with horseradish peroxidase (HRP). Four days after the last injections all the rats were killed, aortas removed and prepared for immunocytology and chemical analysis. Free peroxidase was not detected in the arterial wall and in all immunized rats only faint staining of free anti-HRP antibodies occurred in the intima. In contrast there was a consistent deposition of HRP-anti-HRP antibody complexes in the inner two thirds of the arterial wall in all HRP-immunized animals. Immunization and cholesterol feeding increased the cholesterol content of the aorta and produced early lesions, whereas cholesterol feeding or immunization alone was less effective.

Animals↗
PubMed1978

Immunohistochemical studies on human gastric mucosa. Procedures for routine demonstration of gastric proteins by immunoenzyme techniques.

Two different fixatives were applied to human gastric mucosa for the study of antigenic marker substances. The first consists of 96% ethanol and 1% acetic acid (EA method), the second of 4% formaldehyde, 0.5% picric acid and 0.25% glutaraldehyde (FPG method). Samples of resected gastric specimens were fixed, dehydrated and cleared in benzene and embedded in paraplast. The morphology of gastric tissue was well preserved by both methods and permitted the simultaneous application of classical staining procedures and the immunoenzyme peroxidase technique for the demonstration of antigenic substances. The following marker substances could be demonstrated: Pepsinogen I and II group, surface epithelial antigen, parietal cell antigen, chief cell antigen, antral mucous cell antigen, carcinoembryonic antigen, goblet cell antigen and common site antigen of leucocytes. Various factors responsible for nonspecific reactions, such as endogeneous peroxidase activity and protein interactions were studied. The latter were circumvented by the use of highly purified antibodies or immunoglobulin fractions. The EA method proved to be the method of choice for future routine application of combined classical histology and immunoenzyme histology in gastric and intestinal diseases.

Antigens↗
PubMed1977

Diaminobenzidine cytochemistry in cryo-ultramicrotomy for the detection of peroxidases.

Rat erythrocytes and lymphoid cells were fixed by glutaraldehyde and encapsulated in bovine serum albumin plus rabbit IgG globulins for cryo-ultramicrotomy. A technical procedure is described by which endogenous peroxidases of erythrocytes in ultrathin frozen sections were detected by hydrogen peroxide and diaminobenzidine as hydrogen donor. Modifications of this classical cytochemical procedure proved also useful in cryoultramicrotomy for immunoperoxidase labeling of antigenic determinants in rabbit IgG globulins which have been crosslinked within the supporting matrix of cells.

3,3'-Diaminobenzidine↗
PubMed1977

Intrapulmonary receptors in the Tegu lizard: I. Sensitivity to CO2.

Single unit vagal recordings from intrapulmonary receptors were obtained in decerebrate, paralyzed lizards both during pump ventilation and during unidirectional ventilation on the cannulated, sack-shaped lung. Two types of receptors were identified: (1) CO2-receptors, which increased their discharge frequency as intrapulmonary CO2 concentration decreased but were not sensitive to stretch of the lung. (2) Mechanoreceptors, which rapidly increased discharge frequency when the lung was stretched. These receptors' CO2 sensitivity varied. Lungs of lizards thus appeared to possess both CO2 receptors, which have functional characteristics similar to those in birds, and mechanoreceptors with properties similar to stretch receptors in mammals.

Animals↗
PubMed1977

Intrapulmonary receptors in the Tegu lizard: II. Functional characteristics and localization;.

Intrapulmonary receptors identified in the Tegu lizard by single-unit vagal recording (Fedde et al., 1977) were subjected to a number of stimuli and localized within the lung. Some carbon dioxide receptors could follow periodic changes in intrapulmonary CO2 concentrations as rapidly as 1.3 Hz; No oxygen sensitivity was observed with this receptor type, and halothane markedly depressed the discharge frequency. In response to intravenously injected acetazolamide they increased their discharge frequency and became almost totally insensitive to CO2, suggesting molecular per se is not the direct controller of receptor discharge; These receptors show many of the functional characteristics described for those in the avian lung. Afferent activity from both CO2 and mechanoreceptors could be elicited by electrically stimulating the lung surface. The CO2 receptors appeared to be organized in a receptive field covering more than 1 cm2 of lung surface, multiple receptors being innervated by a single afferent fiber. Activity in afferent fibers from mechanoreceptors could be evoked from only one distinct spot on the lung surface. Conduction velocities of afferent fibers from CO2 receptors ranged from 1 to 3 m-sec-1; from mechanoreceptors, from 1.9 to 5.2 m-sec-1.

Acetazolamide↗
PubMed1977

Evidence for mechanoreceptors in the muscular stomach of the chicken.

Single-fiber, vagal recordings were made from mechanoreceptors in the muscular stomach of the chicken. These receptors increased discharge frequency (i) during gentle compression of the wall of this organ and (ii) when coordinated contractions of the organ were induced pharmacologically.

Animals↗
PubMed1975

Purification of mouse alpha1-fetoprotein and preparation of specific peroxidase conjugates for its cellular localization.

Mouse alpha1-fetoprotein (AFP) was isolated from amniotic fluid by immunoadsorbent columns and preparative electrophoresis. Specific antibodies were isolated from monospecific hyperimmunsera by use of immunoadsorbents, and subsequently coupled with horseradish peroxidase. At the light microscopical level, purified antibody-peroxidase conjugates were used for the cellular localization of AFP in fetal liver by direct and indirect staining methods. Fixatives containing ethanol or aldehydes were tried for antigen staining. Prior to immunocytological reactions, endogenous peroxidases were inhibited by hydrogen peroxide.

Animals↗
PubMed1975

Lymphocyte differentiation and antibody synthesis in the secondary immune response of peroxidase stimulated lymph nodes of rat.

Lymphocyte differentiation and specific antibody synthesis were studied in the course of the secondary immune response of horseradish-peroxidase immunized rat popliteal lymph nodes by electron microscopic immunocytochemistry. From primary immunization, mature plasma cells containing specific antibody remained as long as 10 months. Antihorseradish peroxidase antibodies were localized in lymphocytic blast cells on Day 3 after restimulation with antigen. In the subsequent days blast cells were still present, and shifting to mature stages occured. During immunocyte differentiation and maturation vesicles and tubules of the Golgi complex became filled with specific antibody suggesting occasional secretion of antibody via the Golgi apparatus. At very mature cell stages, antibody was accumulated in distended cisternae.

Animals↗