Joji Ohno

Reassessment of Selectivity Index in Nephrotic Syndrome with Special Reference to the Clinical Significance of a Small-Molecular IgG Fraction in the Urine

The selective index O and the transR IgG have been valuable in clinical use, but they do not appear to always correctly reflect the GBM sieving effect on plasma protein and thus do not correctly predict the response to steroids. We applied a new technique to 22 nephrotic patients with the following results. (a) Fragments of IgG molecules (M-IgG, MW 5-10 X 10(4); S-IgG, MW 1-5 X 10(4)) were present in the urine in addition to normal IgG (L-IgG). These fragments were immunologically identical with the intact IgG molecule and therefore, could falsely portray GMB permeability. (b) The data strongly suggest that the S-IgG fragment found in the nephrotic urine is the IgG-Fc fragment present in increased amounts in such urine. (c) IgG L/S shows a positive correlation with O and transR IgG and can be used as a new and better selectivity index of GBM permeability. This, in turn, may provide a more accurate means of predicting the response to steroid therapy. For example, in the cases we analyzed, the transR IgG and O were incorrect in 31.9% and 22.7%, respectively, whereas with our new method they were incorrect in only 13.6%.

Biochemical Properties of Glomerular Basement Membrane in Daunomycin Nephrosis and Nephrotoxic Serum Nephritis

Glomerular basement membrane (GBM) were isolated from the kidneys of rats suffering from daunomycin nephrosis or nephrotoxic serum nephritis. The GBM from daunomycin nephrotic rats contained significantly less hydroxyproline, hydroxylysine and glycine than that of control rats. There was an increase in glucosamine content in the membrane. No significant change was found in the neutral sugar content. In nephrotoxic serum nephritis, the relative amounts of hydroxyproline, glycine and half-cystine were decreased, whereas the relative amounts of aspartic acid, alanine, lysine and hydroxylysine were increased. The ratio of hydroxyproline to proline and the ratio of hydroxylysine to lysine were decreased. An increase in sialic acid content and a decrease in fucose and hexosamine content and glucosyl-galactosyl-hydroxylysine content were noted in nephrotoxic nephritic GBM. These chemical structural alterations could accounted for the functional disorders of diseased GBM.

Study on the optimum concentration of bicarbonate in dialysate for a reformed dialysate delivery system

Acetate透析用透析液供給装置Centry 2®を重炭酸透析用に改良し臨床応用した. 改良は容易で安価であり, acetate透析で不安定透析となる症例には有用な結果がえられた.電解質液と重炭酸液との混合は定比例混合方式とし, conductivity control potentiometer操作で透析液重炭酸濃度 (D-BC) やNa濃度を変更することが可能で, 試運転中両者の測定値は安定していた. 透析液供給装置内に炭酸Ca・Mg塩析出がみられたが, 4% acetate液の再循環洗浄で解決できた. この改良は, 本来のacetate透析機能にはまったく影響しない.臨床応用は, acetate透析で不安定となる糖尿病性腎症2例と低体重の慢性腎炎1例である. D-BC 27mEq/lで使用中, 神経・精神症状を伴った原因不明の著明な代謝性アルカローシスが糖尿病性腎症例に発生した. 原因として, D-BC 27mEq/l自体高濃度であることが推定された. そこで, D-BC 27以上, 26, 24, 22, 20mEq/lの5種類の透析法を作成し至適D-BCを検討した. 前3透析液使用5時間目での血中重炭酸濃度 (B-BC) は27mEq/l以上となり, 後2透析液使用時ではほぼ24mEq/lの正常域への是正であった. 次にD-BC 22と20mEq/lの透析液につき, B-BCを透析器入口と出口部で検討した. B-BCは3時間目までは出口部, 5時間目では入口部で高値を示した. B-BCの適切な是正と透析後半でのB-BC喪失の少なさより22mEq/l D-BCが至適と考えられた.