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Biomedical subjects

Z Ota

Publications and source records attributed to Z Ota.

At least 271 records · Page 15Linked to original sources
PubMed1980

Molecular sieve in renal glomerular and tubular basement membranes as revealed by electron microscopy.

Bovine glomerular basement membrane (GBM) was isolated and purified according to a modification of Spiro's method. Rat and bovine tubular basement membranes (TBM) were isolated and purified by sonic disruption or by the method of Carlson et al. Electron microscopic studies on the ultrastructure of GBM and TBM were performed after negative staining with 1% phosphotungstic acid solution, pH 7.3. When negatively stained, GBM and TBM were seen as fragments varying in size. The surface of the membranes showed a characteristic felt-like or spongy appearance. At higher magnification, GBM and TBM showed a fine meshwork composed of strands and pores which three-dimensionally resembled a crystal lattice. Pores were fairly uniform in size and shape. They were round, oval or polygonal in shape. Some of the pores were elongated to form short straight or bent channels. Strands were also uniform in diameter and surrounded a pore or channel. For an average of 50 pores, the long dimension was 3.1 +/- 0.6 nm and the short dimension 2.5 +/- 0.3 nm in bovine GBM, 3.8 +/- 1.2 and 2.5 +/- 0.7 nm in bovine TBM, and 4.9 +/- 1.5 and 2.8 +/- 0.6 nm in rat TBM, respectively. The strand was 1.8 +/- 0.3 nm in diameter in bovine GBM, 2.5 +/- 0.6 nm in bovine TBM and 3.7 +/- 0.7 nm in rat TBM for an average of 50 strands. The diameters of the pores were less than or close to the short axis of an albumin molecule. It was concluded that renal GBM and TBM were molecular sieves composed of pores and strands.

Animals↗
PubMed1980

Changes in the molecular sieve of glomerular basement membrane in rats with aminonucleoside nephrosis.

Isolated and purified glomerular basement membranes (GBM) of normal and aminonucleoside (PAN) nephrosis rats were observed by electron microscopy after negative staining. Although GBM of normal rats appeared as a molecular sieve with uniform pores, GBM of nephrotic rats showed enlargement and elongation of the pores. For an average of fifty pores, the long dimension was 40.4+/-10.7 A and the short dimension 13.8+/-3.6 A in nephrosis whereas the long dimension was 12.3+/-2.5 A and the short dimension 8.4+/-1.0 A in normal rats. Changes in the pores in GBM were thought to result in increased permeability of serum protein and hence proteinuria.

Animals↗
PubMed1979

Bartter's syndrome--case report.

A 26-year-old female with Bartter's syndrome associated with Graves' disease is reported. This patient had a history of Graves' disease from the age of 22 and anti-thyroid drug (Methimazole) had been administered for 2 years. Thyroid function returned to normal but general fatigue and polyuria continued. Hypokalemia was diagnosed at 25 years of age and she was referred to our hospital for evaluation. Blood pressure was normal and laboratory data revealed normal thyroid function, hypokalemic alkalosis, high plasma renin activity and high plasma aldosterone concentration. She showed normal pressor sensitivity to norepinephrine infusion, grossly diminished pressor sensitivity to exogenous angiotensin II infusion compared with the normal. A renal biopsy specimen showed juxtaglomerular cell hyperplasia. Electron microscopy confirmed lacis cell (agranular cell) proliferation.

Adult↗
PubMed1979

Ultrastructure of rat renal tubular basement membrane--meshwork structure demonstration by negative staining.

The tubular basement membrane (TBM) (i.e. tubular basal lamina) of rat kidney was shown to be a fine meshwork by electron microscopy after negative staining. Strands of the meshwork formed a regular three dimensional lattice work. The pores of the meshwork were polygonal. There were two main pore sizes: one approximately 30 A in diameter, the other 42--60 A. In view of our previous observation that glomerular and alveolar basement membranes were made up fine meshwork, it is quite possible that the basement membranes of other organs are also made up such fine meshwork.

Animals↗
PubMed1977

Electron microscopic demonstration of meshwork structure in human and bovine glomerular basement membranes.

With the electron microscopic and the negative staining method, the glomerular basement membrane of human and bovine kidneys was shown to have a definite fine meshwork structure. The pores of the meshwork of bovine glomerular basement membrane appeared to be pentagonal or hexagonal in shape. Strands of the meshwork branched three-dimensionally and made up the whole basement membrane. The portion of the sgrand between two neighboring branches was presumed to be a structural unit of the basement membrane. Glomerular basement membrane in man showed a structure similar to that seen in cattle, although the pore size of the meshwork was smaller in man than in cattle.

Animals↗
PubMed1976

Scanning electron microscopy of myeloma cells.

The surface structure of myeloma cells was examined by scanning electron microscopy. The cells were collected from the pleural effusion of a multiple myeloma patient and purified by Conray-Ficoll gradient sedimentation. The cell size ranged from 8 mu to 12 mu in diameter and the microvilli were from 0.8 mu to 1.2 mu in length. The surfaces of the majority of the observed myeloma cells were more villous than lymphocytes.

Aged↗