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Biomedical subjects

S Tsuchida

Publications and source records attributed to S Tsuchida.

At least 343 records · Page 19Linked to original sources
PubMed1979

Dynamics of upper urinary tract during pacemaker blockade induced by pentobarbital.

The transport efficiency of the dog's pelviureteral system was examined during pacemaker blockade induced by pentobarbital. For an analog representation of transport efficiency, changes in balance level between the input and the output were registered and recorded on a polygraph together with perfusion rate, renal pelvic pressure, ureteral electromyogram and bolus volume. Pentobarbital dramatically blocked the pacemaker activity of the renal pelvis, and the ureter simultaneously became aperistaltic. During the period of pacemaker rest, the balance level was maintained at a high level in all dogs studied, indicating that a part of the perfusion fluid was accumulated in the pelviureteral system. Furthermore, the accumulated fluid overflowed through the aperistaltic ureter as a free flow. These results are discussed in relation to the transport efficiency of normal peristaltic transport.

Animals↗
PubMed1978

Effects of ethylenediaminetetraacetic acid-4 sodium solution on the surface of renal calculi and the uroepithelium.

Tetrasodium ethylenediaminetetraacetic acid is one of the most effective agents that dissolve renal calculi, especially calculi containing calcium. To study the dissolving process of calculi in solutions, with or without trypsin, serial thin sections of renal calculi composed of calcium oxalate and/or phosphate were prepared and observed by polarizing microscopy. The effects of the solution on the surface of human renal calculi and rat uroepithelium also were studied by scanning electron microscopy. A remarkable difference in solubility was noted between the crystalline and the amorphous components in struvite calculi. Under the polarizing microscope the dissolving effect of 5 per cent tetrasodium ethylenediaminetetraacetic acid solution on struvite after 30 minutes of incubation was equivalent to the use of saline for 24 hours. The effect of trypsin was not apparent. However, under the scanning electron microscope trypsin accelerated the dissolving effect of the tetrasodium ethylenediaminetetraacetic acid solution in struvite and calcium oxalate calculi. The contradictory findings of the ineffectiveness of trypsin on the thin sections as opposed to the pronounced changes seen on the surface of the calculi could be attributed to the difference in the exposed area. The results suggest that trypsin does not seem to dissolve calculi but mainly facilitates the solution to permeate the calculi. The cellular arrangement of the uroepithelium was preserved in tetrasodium solution and in 0.04 per cent trypsin tetrasodium ethylenediaminetetraacetic acid solution.

Animals↗
PubMed1978

Kappa-type light chain crystal storage histiocytosis.

An autopsy case of systemic histiocytosis with excessive deposition of kappa-type light chain crystals was reported in a 58 year-old man who had consistently showed kappa-type light chain paraproteinemia, Bence Jones proteinuria and hypogammaglobulinemia for about 10 years until his death. However, no bony destruction was found by repeated X-ray examinations. At autopsy, extensive hyperplasia of crystal-storing histiocytes was observed in the bone marrow, spleen, liver, lymph nodes, interstitial tissues of visceral organs and loose connective tissues. In the bone marrow and some other tissues, mild proliferation of plasmocytoid cells containing small crystals were found. Histochemically the crystals positively stained with various methods for amino acids and proteins, especially with Weigerts' method for fibrin. Ultrastructurally intralysosomal crystal deposition was confirmed in the storage histiocytes and derivation of the crystals from Golgi's sacculi in the plasmocytoid cells was suggested. Biochemically the crystals were regarded as mainly consisting of dimers of a variable half of light chain immunoglobulin and immunochemically and immunohistochemically reacted to anti-kappa type light chain serum. Such a generalized storage histiocytosis may be secondarily induced by immunoglobulin synthesized in plasmocytoid cells.

Crystallization↗
PubMed1978

The simultaneous recording of the rhythmic contraction and electrical activity of the renal previs--a new in vitro method.

A new in vitro method which enables the simultaneous recording of the electromyogram from various regions of the renal pelvis and the pressure changes associated with those electrical activities is described in an experiment on canine kidney. At the proximal end of the renal pelvis, the interval of the electromyogram was constant and pelvic pressure changes showed rhythmic activity, while the discharge interval of the proximal end was the same as the pressure interval. However, the discharge intervals of both the pelvic center and the pelviureteric junction were found to be multiples of that of the proximal end of the pelvis.

Animals↗
PubMed1978

Effect of urinary bladder distension on renal blood flow, blood pressure and plasma renin activity.

The effects of urinary bladder distension on renal blood flow, blood pressure and plasma renin activity (PRA) were studied in 50 mongrel dogs anesthetized with chloralose. The dogs were divided into three groups. Group I was composed of dogs intact except for having undergone the surgical procedure for measurement and instillation of 0.9% saline to the bladders. Group II was composed of dogs whose bilateral ureters had been cut. Group III was composed of anephric dogs. Renal blood flow showed reduction during bladder distension in Group I and Group II. This reduction was produced not only by hydraulic mechanisms through the ureters during bladder distension, because the reduction was also observed in the dogs whose ureters had been cut. The rise in blood pressure and increase in PRA were observed in Group I and Group II, while the anephric dogs showed the rise in blood pressure during bladder distension despite the absence of PRA. Therefore, it appeared that the renin-angiotensin system did not directly relate to the rise in blood pressure during bladder distension.

Animals↗
PubMed1977

A new operative fiberpyeloscope.

We describe a flexible fiberpyeloscope with which it is possible to extract renal pelvic and caliceal stones easily. The tip of the fiberpyeloscope can be deflected 90 degrees up or down from the basic position with a hand-manipulated angle deflector know on the fiberpyeloscope grip. This flexibility allows the inside of the renal pelvis to be observed clearly from every direction. Specially designed stone forceps can be inserted through the channel of the fiberpyeloscope into the renal pelvis to grasp pelvic stones under direct visual observation. The fiberpyeloscope has been used in 4 cases of renal pelvic stones in which the pelvis was exposed by a subcostal flank incision. The stones were extracted successfully with the fiberpyeloscope, which was introduced through a small incision on the pelvis.

Endoscopes↗
PubMed1977

A constant electrical activity of the renal pelvis correlated to ureteral peristalsis.

Using a bipolar macroelectrode, simultaneous recordings of both pelvic and ureteral electromyograms (EMG) were carried out in dogs. The recordings were performed at 3 stages of urine flow; oliguric, increasing and diuretic stages. The results showed that the interval of the pelvic discharge was constant while its speed of propagation was slower than that of the ureter (1.32 cm/sec and 2.12 cm/sec, respectively). At oliguric stage the interperstaltic interval in the ureter constituted a multiple of the pelvic discharge interval. Ureteral peristaltic rate reached that of the renal pelvis with increasing urine flow. These results are discussed in relation to a hypothesis of a renal pacemaker.

Animals↗
PubMed1977

A method to register a dynamic balance of the upper urinary tract.

Using a specially designed circuit with an UP-DOWN counter, a new method is briefly described for investigation of the upper urinary tract. It allows sequential measurements of the balance level between input and output of the pelviureteral system in animal experiments.

Animals↗
PubMed1976

Hypertension and plasma renin activity in experimentally induced chronic pyelonephritis.

The present authors conducted a series of experiments with mongrel dogs, in which unilateral chronic pyelonephritis was induced and postoperative changes in blood pressure and plasma renin activity were observed over a period of 3 months. The pyelonephritis infection was brought about by a method involving vesicoureteral reflux and ureteral dysfunction, as described in a previous paper. Pre- and postoperative levels of systolic pressure were compared, but no definite trends were found for the first 3 weeks after operation. At 30, 60 and 90 days the pressures were found to have risen by 21.2 +/- 14.6 and 17.1 +/- 16.7 mm Hg, respectively. No appreciable change in the plasma renin activity was found, however, at any stage. From these results it was concluded that experimentally induced chronic pyelonephritis in dogs caused a rise in blood pressure. No connection between the pyelonephritis and the renin angiotensin system was found.

Animals↗