Displacement measurement that uses transient photoelectromotive force effects in CdTe:V with frequency-modulated lasers.

A new method of displacement measurement that uses the transient photoelectromotive force effects that arise in semiconductors illuminated by two frequency-modulated lasers is proposed and demonstrated experimentally. A height resolution of 0.85 microm was achieved experimentally; theoretical analysis charts the path toward eventual improvement of this resolution.

A rosette assay for the determination of C 1 q receptor-bearing cells.

A rosette assay for the identification of cells with receptors for C 1 q is described. Glutaraldehyde-treated bovine erythrocytes bound C 1 q specifically, and the reagent thus prepared provided a valid indicator for rosette formation mediated by C 1 q receptors. The presence of these receptors on the membrane of a subset of human peripheral lymphocytes (mainly non-G cells) and on B-derived lymphoblastoid cells was confirmed. Rosette formation was dependent on the number of C 1 q molecules bound per indicator cell and was specifically inhibited by soluble native C 1 q and pepsin-resistant C 1 q fragments. These data, together with the reduced binding activity of C 1 r-C 1 s-associated C 1 q, indicated that the C 1 q binding sites for lymphoid membranes are expressed on the collagen-like moiety, C 1 q rosette formation provided a simple new procedure for fractionation of human lymphocyte populations and separation from phagocytes that do not express receptors for C 1 q.

The second component of complement (C2) as an index of hereditary angioneurotic edema.

Measurements of C2 hemolytic activity were performed in the sera of 13 patients with Hereditary Angioneurotic Edema. Prior to treatment, C2 values correlated with the severity of the disease in each patient. During androgen therapy with Danazol, C2 measurements reflected the clinical benefit of the drug more accurately than C4 levels, thus explaining the effectiveness of low drug doses. This study also suggests that breakdown products of C2 may play an essential role in the pathogenesis of the edema.

[Detection of circulating immune complexes by the C1q complement fraction deviation test. 1st application in the study of human glomerulopathies]. / Recherche de complexes immuns circulants par le test de déviation de la fraction C1q du complément. Premières applications à l'étude des glomérulopathies humaines

The C1q deviation test measures the interference of circulating immune complexes in the fixation of radioactive C1q on target cells. The test was carried out in a large sample of cases of glomerular nephropathies, on the serum of patients with hypertension and on control sera. Positive results were frequently obtained with the sera of patients suffering from acute glomerulonephritis and membranous glomerulonephritis. Positive results were rarer in cases of minimal change discase and of membranoproliferative glomerulonephritis. These results suggest that the deviation of C1q in the serum of patients with various types of glomerulone phropathy may be due to circulating complexes but also to other substances. They indicate that efforts should be continued to isolate and biochemically identify the C1q binding substances in pathological sera.