Search PubMed⌕ Search

Biomedical subjects

C Klessen

Publications and source records attributed to C Klessen.

At least 55 records · Page 3Linked to original sources
PubMed1982

[Use of chromogenic substrates in the clarification of disorders in the early stages of blood coagulation].

The kallikrein specific chromogenic peptide substrates S-2302 (KABI) and Chromozym PK (Boehringer) were used in the first analysis of a familial defect in the early stage of clotting. Slight to extensive prolongation of the activated partial thromboplastin time was seen in the affected persons. Using dextransulfate for activation of plasma marked deficiency in kallikrein activity was found in 3 persons. Using factor XIIa (activated Hageman factor) for activation normal prekallikrein levels were found in 2 of them whereas factor XII levels, however, were below normal. The third had a prekallikrein deficiency presumably caused by oral contraceptives. In a fourth member of the family factor XII deficiency was found with normal kallikrein activity. The application of chromogenic peptide substrates for analysing the early stage of clotting has to take into account the special mechanisms of activation.

Adolescent↗
PubMed1981

Glycogen in pancreatic islets of steroid diabetic rats. Carbohydrate histochemical detection and localization using an immunocytochemical technique.

In the islets of the rat pancreas, steroid diabetes induced by triamcinolon-acetonid leads to degranulation of the B cells and glycogen infiltration. The glycogen cannot be satisfactorily detected using methods like the chromic acid technique according to Bauer, staining with Best's carmine, or the usually applied periodic acid-Schiff (PAS) reaction. Glycogen detection is improved, however, when lead tetraacetate is used in place of periodic acid as oxidizing agent. When combining the carbohydrate detection method with the peroxidase--antiperoxidase (PAP) method used for immunocytochemical detection of the various pancreatic islet hormones, paraffin sections reveal that glycogen is primarily localized in granulated B cells; the degranulated B cells also contain glycogen, though in smaller amounts. In contrast, the islet cells containing somatostatin, glucagon and pancreatic polypeptide are nearly free of glycogen.

Animals↗
PubMed1981

Cytochemical detection of proteases in synovial fluid of arthritic joints.

A cytochemical method can be used to detect neutral proteases in polymorphonuclear leukocytes (PMN cells) in synovial fluid smears obtained from arthritic joints. Using this method, incubation of fixed smears in NaCl-borate buffer causes release of neutral PMN proteases, the enzymatic activity of which id documented in the degradation of exudate protein in ring-shaped areas centered around the neutrophils(halo effect). Such halo formation can also be detected around certain large mononuclear cells, as well as around very small particles - which may represent thrombocytes. Application of trypsin inhibitors and various antirheumatic agents causes concentration-dependent inhibition of halo formation.

Arthritis, Rheumatoid↗
PubMed1980

Cytochemical investigation of neutral proteases in polymorphonuclear (PMN) neutrophils in acute inflammatory diseases.

Neutral proteases can be released from PMN neutrophils in blood smears from healthy subjects by incubation with NaCl-borate buffer. The activity of the PMN proteases can be revealed by the degradation of erythrocytes and plasma within ring-shaped areas centered around each neutrophil (halo effect). During the acute stage of various inflammatory diseases (pneumonia, meningitis, cholecystitis, etc.) the activity of neutral PMN proteases is substantially reduced, as reflected by reduced halo formation. After recovery, halo formation returns to normal. Temporary lowering of neutral PMN proteases is thus one of a series of functional defects of PMN neutrophils which are detectable in the course of acute infectious diseases. These include reduced phagocytosis, altered chemotaxis and reduced bactericidal function. The cytochemical test for neutrophilic granulocyte function used in the present investigation is especially practical by comparison with the other techniques: it saves time and is simple to perform.

Acute Disease↗
PubMed1980

Inhibition of neutral proteases from polymorphonuclear (PMN) neutrophils by salicylazosulfapyridine (SASP).

Cytochemical methods were used to demonstrate the inhibitory effect of salicylazosulfapyridine (SASP) on the activity of neutral proteases produced by neutrophilic granulocytes (PMN proteases). The SASP metabolites (5-aminosalicylic acid and sulfapyridine), produced by splitting of SASP by bacteria in the colon, did not inhibit the activity of PMN proteases. Paradoxically, sulfapyridine intensified PMN protease activity. A similar effect however could not be demonstrated for 5-aminosalicylic acid.

Adult↗
PubMed1979

[Demonstration of neutrophil leukocytes on blood smears by a modified colloidal iron reaction (author's transl)].

Using a modified colloidal iron reaction two positively reacting components in neutrophil leukocytes are discernible: 1. In neutrophils of unfixed smears the outer membrane or surface coat is stained. 2. After fixation with buffered formalin, formalin-sublimate or Helly's fluid a strongly reacting cytoplasmic component is demonstrable. After fixation with formalin-sublimate or Helly's fluid the latter has been proven to be sensitive against treatment with sialidase thus indicating the presence of sialic acid residues in neutrophil granulocytes.

Binding Sites↗
PubMed1979

[On the cytochemical demonstration of glycogen in neutrophil granulocytes: periodic acid-Schiff reaction and diastase (amylase) digestion test (author's transl)].

The results of the present investigation indicate clearly that treatment of blood smears with diastase resp. amylase is unsuitable to identify glycogen in neutrophil granulocytes. This may be attributed to the contamination with proteases of commonly used preparations of diastase resp. amylase. Thus strong PAS-reactive material which presents most probably not glycogen but PAS-positive glycoproteins may be eliminated by the proteolytic activity of the contaminants. - In detail it has been shown that susceptibility resp. resistance of the PAS-positive material against treatment with diastase resp. amylase is highly dependent on both type of fixation and fixation time: Fixation with formol free absolute alcohol (ethanol, methanol), leads also after prolonged fixation time to a complete loss of PAS-staining after preliminary treatment with diastase resp. amylase. On the other side after fixation with formol containing fixatives (for example formol/ethanol and acetic acid/formol/ethanol) only after short term fixation practically a complete loss of PAS-staining material is observed. However, after long term fixation more or less complete resistance of the PAS-stainable material against treatment with diastase resp. amylase has been found.

Amylases↗
PubMed1978

The histochemical demonstration of sialic acid residues in pancreatic islets.

Using a modified colloidal iron reaction in connection with neuraminidase extraction test 3 different sialic acid-containing components have been demonstrated in pancreatic islets comprising golgi region and glycocalyx layer of islet cells and intrainsular capillary walls. The colloidal iron positive cationophilia increased markedly after treatment with alkali; an effect which might be due to deesterification, thus exposing additional free carbonyl groups of sialic acid residues.

Animals↗
PubMed1978

[Demonstration of an alkali PAS-effect using periodic acid at low concentration (author's transl)].

It has been shown that an isolated KOH PAS-effect of epithelial mucosubstances in the colonic mucosae of the rat can be demonstrated also without the conventionally used preliminary oxidation/reduction step. The method is based on the use of strongly diluted periodic acid after previous treatment of tissue sections with ethanolic KOH. As the positive reacting material has been proven to be sensitive against treatment with neuraminidase the modified KOH PAS-reaction should be related to the presence of acylated sialic acid residues in mucosubstances of the colonic mucosae of the rat.

Animals↗
PubMed1978

On testing the activity of proteases from human polymorphonuclear neutrophils on blood smears.

A cytochemical method is presented for the demonstration of proteases in human polymorphonuclear (PMN) neutrophils on fixed blood smears. This new technique is based on solubilization of proteases from PMN neutrophils by incubation with 0.25 M NaCl in borate buffer at pH 8.5 which leads to degradation of erythrocytes and plasma in a disclike zone (halo) around centrally situated PMN neutrophils, an effect that is visualized by staining smears using a modified colloidal iron reaction. Halo formation is inhibited by trypsin inhibitors of soya-bean as well as of chicken egg white mucoid and by phenylmethyl-sulfonylfluoride.

Histocytochemistry↗