Search PubMed⌕ Search

Biomedical subjects

K Meyer

Publications and source records attributed to K Meyer.

At least 235 records · Page 13Linked to original sources
PubMed1985

Sequential administration of human and porcine factor VIII for surgical treatment of a parotid tumour in a patient with a factor VIII inhibitor.

The sequential use of human and porcine factor VIII for the treatment of a patient with a moderately high titre (38 Bethesda units) factor VIII inhibitor enabled us to provide adequate haemostatic cover for 17 days. In this period a pleomorphic adenoma of the parotid gland was removed. Bleeding did not occur and wound healing was uneventful.

Adenoma, Pleomorphic↗
PubMed1985

Polyamine and prostaglandin markers in focal cerebral ischemia.

This study examines the pathophysiology of stroke secondary to focal cerebral ischemia. The interaction of arachidonic acid metabolites and polyamines, a class of ubiquitous ornithine-derived molecules with important membrane effects on edema, Ca++-dependent endocytosis, platelet function, and prostaglandin (PG) formation, are correlated with regional changes in H2 clearance, cerebral blood flow (rCBF), ischemic edema, and somatosensory evoked responses (SSERs) after middle cerebral artery (MCA) occlusion. Thirty cats were studied up to 3 hours before and 6 hours after right MCA occlusion. Four areas of brain showing different levels of perfusion after MCA occlusion were sampled for tissue levels of PGs: 6-keto-PGF1 alpha, PGE2, and as well as thromboxane B2 (TXB2), ornithine decarboxylase activity (ODC) (a measure of polyamine activity) and gravimetric determination of cerebral edema. After right MCA occlusion, right hemisphere SSER amplitude decreased and interpeak latency increased markedly. rCBF was distributed into zones of dense, partial, and no ischemia ranging from 12.6 to 59.4 ml/100 g/minute. Ischemic edema was distributed inversely to rCBF and was increased in areas of dense ischemia (85.2 +/- 0.5%) and ischemia (82.7 +/- 0.7%), but not in partially ischemic or control areas. 6-Keto-PGF1 alpha (1257.3 pg/mg), PGE2 (1628.5 pg/mg), and TXB2 (1572.8 pg/mg) were all significantly (P less than 0.05) increased in areas of partial ischemia that had not yet developed edema. ODC levels were significantly elevated (3812 pmole/g/hour, P less than 0.05) and increased with time in areas of slightly denser ischemia that showed an intermediate increase in edema, but not the presence of infarction. This is the first demonstration that ODC, the rate-limiting enzyme for polyamine synthesis, is stimulated by cerebral ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)

6-Ketoprostaglandin F1 alpha↗
PubMed1985

[Significance of fixed anaerobic threshold, training lactate and training heart rate for bicycle ergometer training with myocardial infarct patients].

UNLABELLED: 302 male myocardial infarction patients were divided into 4 groups according to their symptom-limited physical working capacity and examined during bicycle ergometer training. Lactic acid and heart rate during training were measured. RESULTS: Arterial lactic acid and training heart rate decreased proportionally with the reduction of the maximal symptom-limited working capacity. Arterial lactic acid levels in 4 training groups of 100, 75, 50 and 25 watts were 2.23 (2.56) mmol/l, 1.87 (2.32) mmol/l, 1.58 (1.73) mmol/l and 1.20 (1.11) mmol/l, respectively, p less than 0.001 (in bracket = with beta blocker). Decrease in arterial lactic acid levels according to the reduction of working capacity corresponded to a decrease of training heart rate. In patients with beta blocker therapy results were less pronounced. Intensity of training corresponded to about 80% of VO2 measured as maximal symptom-limited physical working capacity. Training heart rate corresponded to about 85% of maximal heart rate as measured at symptom-limited physical working capacity. The so-called fixed anaerobic threshold of 4 mmol/l lactic acid was not reached by patients with myocardial infarction up to a training intensity of 100 watts (approximately 1.3 watts/kg). From this study it can be concluded that fixed anaerobic threshold and lactic acid are of secondary importance in determining the intensity of endurance training in patients with myocardial infarction.

Adrenergic beta-Antagonists↗
PubMed1985

Maximum likelihood estimation of variance components for a multivariate mixed model with equal design matrices.

An algorithm is described for estimating variance and covariance components by restricted maximum likelihood for a multivariate mixed two-way classification with equal design matrices. The procedure involves a transformation to canonical scale, effectively reducing a q-variate analysis to q corresponding univariate analyses. A small numerical example is given as well as a large-scale practical application.

Analysis of Variance↗
PubMed1984

Natural killer (NK)-cell activity and antibody-dependent cellular cytotoxicity (ADCC) in primary preleukemic syndrome.

In 13 patients with a multi-parameter based diagnosis of primary acquired preleukemic syndrome (PPS), natural killer (NK) cell activity and antibody-dependent cellular cytotoxicity (ADCC) were investigated on peripheral blood mononuclear cell (MNC) fractions. In all but two patients a defective NK activity was found. Lymphocyte-monocyte mixture experiments demonstrated that this was not due to suppressor monocytes. Furthermore, NK activity was defective when both myeloid and non-myeloid target cell lines were used. Addition of human leukocyte interferon to the NK cultures augmented the cytotoxicity, which exhibited the same kinetics as that of normal controls, but NK activity levels remained subnormal. These data strongly indicate that the decreased NK activity seen in the patients is due to a decreased number of circulating NK cells. In contrast ADCC was within the normal range both when MNC suspensions as well as when purified peripheral blood lymphocytes were used as effector cells thus ruling out subnormal lymphocyte ADCC masked by the presence of monocyte ADCC. These results demonstrate that PPS patients have a selective NK defect with an intact lymphocyte ADCC function. Whether this defect will prove to be valuable in the assessment of a malignant transformation in a given patient will await further longitudinal NK studies and clinical follow-up of the patients.

Adult↗
PubMed1983

A baseline study of periodontal conditions among youths and adults in Portugal.

A study was undertaken in 1979 to obtain baseline data of periodontal disease and treatment needs among rural and urban Portuguese. From Montemor-o-Novo, Alentejo and from Lisbon, 255 persons (121 males, 134 females) aged 15-44 yr were selected by a stratified quota sampling method and examined under field conditions using both Russell's Periodontal Index (P.I.), slightly modified, and components of a proposed new WHO method. The latter formed the basis for estimation of treatment need according to the Community Periodontal Index for Treatment Needs (CPITN). Periodontal disease as assessed by the P.I. exhibited epidemiologic characteristics which in several respects were similar to those reported in other populations. Severity increased with increasing age and there were trends towards more severe disease in males than in females, and more severe disease in rural than in urban districts. Relatively few cases of advanced periodontitis were detected by the P.I. as applied in this study. The underestimation of disease prevalence inherent in the scoring method, the high tooth mortality and the fact that only relatively young individuals were studied may have contributed to this finding. Great need for various types of periodontal therapy were found through CPITN assessments. However, relatively few individuals were in need of "complex periodontal therapy" as assessed by the CPITN.

Adolescent↗
PubMed1983

Isolation and characterization of ichthyosan from tuna vitreous.

Ichthyosan has been prepared from tuna vitreous. Glucuronic acid was found to account for the total uronic acid content of the macromolecule, while the hexosamine content was a mixture of N-acetyl-glucosamine and N-acetyl-galactosamine. When ichthyosan was gel filtered on Sepharose 2B or Sephacryl S-300, using sodium or calcium chloride, the elution profile of the column gave only one peak indicating no separation between glucosamine and galactosamine containing fractions. Similar results were obtained when ichthyosan was chromatographed on DEAE-cellulose using a salt gradient both in the presence and absence of 7.0 M urea. When ichthyosan was gel filtered in 4.0 M guanidine-HCL and subsequently chromatographed on DEAE-Sephacel or DEAE-cellulose, three well separated fractions were present. The two major fractions (II and III) were characterized as chondroitin and hyaluronic acid respectively; while fraction I representing about 3-5% of the total polysaccharide content of ichthyosan was identified as a keratan-like molecule. The same pattern was obtained when ichthyosan was digested with proteolytic enzymes and subsequently chromatographed on DEAE-cellulose or DEAE-Sephacel. Based on these findings it is concluded that in ichthyosan chondroitin, hyaluronate and keratan-like molecular chains are bound to proteins in non-covalent linkages.

Animals↗
PubMed1982

Evidence that a reducible xylosyl-lysine is the protein linkage of dermatan sulfate.

Dermatan sulfate, purified by standard methods, displayed one spot at the position of the standard after two-dimensional cellulose acetate electrophoresis and was 99% in GalN, 21.5% in sulfate, and 0.6% in protein; Gal and Xyl (2:1) were the only neutral sugars detected. Its glucuronic acid/iduronic acid ratio was 0.15 and its Mr was approximately equal to 16,000. On reaction with 0.4 M NaOH, its reducing group(s) determined as Glc increased by 71% with concomitant separation of protein and polysaccharide and no alteration of the amino acids; when this reaction was repeated in the presence of 0.3 M NaBH4, only 31% of Lys was detected by standard amino acid analysis and none by TLC of the dansylated amino acids; alkaline cleavage in these conditions yielded only 30% of the original Xyl, xylitol, and a ninhydrin-positive substance different from GalN, which had the retention time of xylitol on Affi-Gel 601 and was also obtained from reduction of dermatan sulfate with a 400-eq excess of Na3BH4 in water under conditions that did not cleave the dermatan sulfate-protein bond. The data indicate that a reducible xylosyl-lysine is the protein linkage of dermatan sulfate from calf ligamentum nuchae.

Amino Acids↗
PubMed1981

Sequential hydrolysis of hyaluronate by beta-glucuronidase and beta-N-acetylhexosaminidase.

1. Hyaluronate extracted from rooster comb was digested by a mixture of beta-N-acetylhexosaminidase and beta-glucuronidase with simultaneous dialysis for 96 h. 2. The produjct, yielding 99.6% of a mixture of mono- and oligo-saccharides, was purified by gel chromatography and analysed for glucuronic acid, N-acetylglucosamine and other sugars. 3. The oligosaccharide portion was chromatographed on DEAE-cellulose, and the effluent fractions were analysed for glucuronic acid and N-acetylglucosamine, reduced with NaBH4, digested by beta-N-acetylhexosaminidase and subjected to acid hydrolysis and glucosamine determination. 4. GlcNAc-GlcA-GlcNAc, GlcA-GlcA-GlcNAc and GlcA-GlcA-GlcA-GlcNAc were the oligosaccharides obtained, which resulted from the transferase activity of the enzymes and represented 57% of the digestion products. The results demonstrate that this hyaluronate is an unbranched polymer of approximatey equal amounts of glucuronic acid and N-acetylglucosamine. The data also indicate that if this glycosaminoglycan contains any of the neutral sugars for which it was analysed, their concentration must be less than 0.020% of the sum of the known components.

Acetylglucosamine↗
PubMed1981

[Immunological investigations of patients after thermic injury (author's transl)].

A burn toxin, which is important for the manifestation of clinical and septical processes during the burn disease, was isolated from burned skin of mice. Using this antigen we have studied the immunological reactions against burn toxin in 10 patients following thermic trauma. We determined the specific antibodies against the burn toxin by means of the passive hemagglutination test, the level of IgM, IgG and IgA in the serum using Mancini-immunodiffusion, the burn toxin binding cells by means of the antigen specific rosette technique and the cell-mediate immunity using the macrophage electrophoretic mobility test (MEM-test). A rise of the burn toxin-specific cells could be observed with maximum at day 4 and a second peak at day 10 and cell mediated immunity between day 10 and day 15. The titer of specific antibodies increased, most following an initial decrease, after day 6, a correlation seemed to exist between this titer and the level of immunoglobulins in the serum.

Antibody Formation↗
PubMed1980

[Differential diagnosis of liver and biliary tract diseases in a regional hospital].

Between 1 Jan 1977 and 31 Dec 1979 459 patients were admitted as cases of hepatitis and with suspicion of hepatitis. Opposite to this number stood 613 patients with diseases of the biliary ducts. Only by the large-scale use of invasive-diagnostic methods we could perform and adequate diagnostics, the results of which are demonstrated in this paper. Clinic and results of serological examinations, the value of which is without doubt, are at the present date not yet suited to substitute the liver blind puncture and the laparoscopy in the same value. Recently decisive progress was achieved in the field of diagnosis by the introduction of sensitive radiotests and enzyme immune tests for the proof of virus hepatitides. By means of these new investigation methods prerequisites have been created to reduce the still high dark number in cases of anicteric hepatitis and subclinical cases of hepatitis.

Biliary Tract Diseases↗