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Biomedical subjects

K H Langer

Publications and source records attributed to K H Langer.

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

Lecithin-cholesterol-acyltransferase deficiency: autosomal recessive transmission in a large kindred.

Thirty-four members of a single Sardinian kindred with lecithin-cholesterol-acyltransferase deficiency have been studied. The kindred spans four generations and the parents of the two affected siblings are blood relatives. Segregation of the acyltransferase deficiency gene in the family clearly demonstrated an autosomal recessive mode of inheritance. Thirteen family members, including all obligate heterozygotes, had roughly half-normal acyltransferase activities (mean +/- S.D. = 0.39 +/- 0.06 mU/ml) when compared to 17 intrafamilial controls and spouses (mean +/- S.D. = 0.72 +/- 0.09 mU/ml) and 40 blood donors from Marburg/Lahn (mean +/- S.D. =0.76 +/- 0.1 mU/ml). Characterization of the heterozygotes did not reveal abnormalities in their plasma lipoproteins. LCAT deficiency and the beta-thalassaemia trait coexisting in this kindred segregated independently.

Consanguinity↗
PubMed1975

Lipoproteins in lecithin-cholesterol-acyltransferase(LCAT)-deficiency. II. Further studies on the abnormal high-density-lipoproteins.

The lipoproteins from two sibs with familial lecithin-cholesterol-acyltransferase(LCAT)-deficiency were further characterized. Comparatively lipoproteins from patients with secondary LCAT-deficiency were studied. Both groups of patients had particles of unusual size and shape in the alpha1-(HD-2)-lipoprotein subfraction. The abnormal HDL-2 particles were disk-like in appearance with a major axis of about 180 A and a minor axis of about 40 A and tended to aggregate into long coinlike stacks. The abnormal HDL-2 particles contained the normal protein constituents of HDL Apo A-I, Apo A-II and Apo C but in addition a major polypeptide with a M.W. of 39000 not seen in significant amounts in normal high-density-lipoproteins. This polypeptide was found identical in size, isoelectric focusing and immunochemically with an arginine-rich normal polypeptide constituent of very-low-density-lipoproteins designated apoprotein E. Presence of this protein marker in the HDL allowed the specific immunological detection of the abnormal HDL-2 (LP-E) in plasma. Further minor biochemical abnormalities were observed in the lipoproteins of the patients with familial LCAT-deficiency. However, the main protein constituents of their HDL, the Apo A, Apo C and Apo E polypeptides, were found to be identical electrophoretically and by analytical isoelectric focusing with their normal counterparts. The data suggest that the basic genetic defect in the hereditary disease leads to a deficient activity of the LCAT-enzyme and that all abnormalities in the lipoprotein spectrum are secondary.

Acetyltransferases↗
PubMed1975

The ultrastructural basis of permeability to proteins in normal and nephrotic glomeruli. Electron microscopic and micropuncture studies using ferritin as a tracer.

Following microinjection of ferritin into urinary space of the rat renal glomerulus in vivo, permeability of the visceral epithelial wall was examined with electron microscope. Results indicated that in normal glomeruli ferritin molecules can be retained by the slit diaphragmata of the eithelial cells; this suggests a barrier function of the slit diaphragmata. The nephrotic glomeruli, observations suggested a channel-like pathway to proteins penetrating the epithelial layer. The channel is formed by only one single cell and therefore, the term 'percellular channel' is proposed for that formation.

Animals↗
PubMed1975

[Light and electron microscopy of human vocal muscle in recurrent laryngeal nerve paresis (author's transl)].

In longstanding recurrent laryngeal nerve paresis with parmedian fixation of the vocal cord the fine structure of the vocal muscle is surprisingly well preserved. Though there are in part bundles of atrophic muscle fibers and increased connective tissue, the normal ultrastructure of the remaining muscle and of the myelinated nerves remains always intact. It is assumed that the vocal cord is prevented from regaining its motility both by the increased connective tissue which misdirects the nerve fibers and by irreverisble changes of the cricoarytaenoid joint. The results are discussed in relation to attempts of reconstructive surgery of the recurrent laryngeal nerve as well as various problems in the neurophysiology of the laryngeal muscles.

Adult↗