agar and Kidney-Calculi

A simple and easy-to-handle method for measuring calcium oxalate crystal formation in whole urine samples using a gel system is described. To prove reliability of the method, the crystallization-inhibiting effect of a number of well-known, so-called inhibitors of crystallization is demonstrated. In testing urine samples from recurrent stone formers and healthy controls, we found a significant difference in the inhibitor index, the stone formers producing more crystals than the controls. Experiments in test persons with oral loading of magnesium compounds and alkalinizing substances suggest that this effect is probably caused by alteration of the urine composition, e.g., a lower excretion of inhibitors by the stone formers.

Topics: Agar; Calcium Oxalate; Citrates; Citric Acid; Crystallization; Humans; Kidney Calculi; Magnesium; Magnesium Chloride; Models, Biological; Risk

A procedure for studying urinary stones by various microscopic techniques is described. The stones are sectioned into approximately 0.2 to 1.0 mm. thick pieces using a low-speed saw. The sections are then embedded in agar and decalcified using 0.25 M ethylenediaminetetracetic acid at pH 7.2. The decalcified residue is then processed for light microscopy and scanning and transmission electron microscopy as with any other biological tissue. The results indicate that the ethylenediaminetetracetic acid-insoluble stone matrix keeps its architectural integrity and can be studied like other biological materials.

Topics: Agar; Edetic Acid; Humans; Kidney Calculi; Microscopy, Electron; Microscopy, Electron, Scanning

Topics: Agar; Bacteriuria; Culture Media; Glomerulonephritis; Humans; Kidney; Kidney Calculi; Mycoplasma; Mycoplasma Infections; Phenacetin; Punctures; Pyelonephritis; Ureter; Urinary Bladder; Urine