Yoshihisa Ohtawara

Usefulness of Fiberoptic Pyeloureteroscope in the Diagnosis of the Upper Urinary Tract Lesions

Fiberscopes for the observation of the upper urinary tract (pyeloureteroscopes) have improved markedly in terms of resolution and durability. With these improved pyeloureteroscopes, transurethral observation of upper urinary tract lesions was performed 42 times in 40 cases from April 1979 to May 1983. The guide tube method (J. Urol. 112: 176-178, 1974) was used for insertion of the fiberscope into the ureter. At present, our transurethrally passed pyeloureteroscope is useful in the diagnosis of some upper urinary tract lesions which are not visualized or confirmed by other current image diagnostic procedures. However, it should be noted that it does not visualize all parts of the upper urinary tract - especially the lower calyx. Insertion to the target is also sometimes difficult and we must be careful in the interpretation of findings because of inevitable image distortion and the similarity between inflammation and urothelial tumor.

Telomerase activity as an indicator of potentially malignant adrenal tumors.

Telomerase is an enzyme that adds repeated telomere sequences to the ends of chromosome arms. It helps maintain both the length of telomere and infinite cell proliferation. In recent years, telomerase activity has been considered an important characteristic that differentiates between normal and cancerous cells. Because the authors often encountered difficulties in distinguishing between benign and malignant adrenal tumors, they investigated whether the expression of telomerase activity could distinguish potentially malignant adrenal tumors.

Operative Fiberoptic Nephroureteroscopy: Removal of Upper Ureteral and Renal Calculi

We tested 2 prototypes of an operating fiberoptic nephroureteroscope, measuring 3.5 and 4.5 mm. in diameter, that have an adequate working channel for auxiliary instruments and irrigation. Difficulty in passing the fiberscope through the ureteral orifice was overcome by dilation with balloon and polytetrafluoroethylene (Teflon) dilators. Our initial trial for stone retrieval under fiberscopic control was performed on 21 patients with upper ureteral and renal calculi. A stone was removed successfully in 15 of the 21 patients (71 per cent). After electrohydraulic lithotripsy calculi were extracted successfully in 9 of 11 patients (82 per cent). Three patients suffered ureteral perforation. The fiberscope was especially helpful when an upper ureteral stone moved back to the kidney during stone manipulation.

Laparoscopic Nephrectomy for Atrophic Kidney Associated with Ectopic Ureter in a Child

An atrophic right kidney located in the pelvic cavity associated with an ectopic ureter was completely removed from a 4-year-old girl by laparoscopic surgery. There were no serious complications during the operation or the postoperative period. The light shining from the tip of a fine fiberscope inserted into the ureter was used to delineate this structure during laparoscopic surgery.

Bredinin treatment in clinical kidney allografting

Bredinin, a new nucleoside antibiotic isolated from Eupenicillium brefeldianum, and steroids were used as immunosuppressive agents in 31 renal transplant patients; 17 of them received grafts from living-related donors and 14 from cadavers. The one-year graft survival rates were 100% in renal recipients from living donors and 69.2% in cadaver kidney recipients. There was no serious complication from the use of these immunosuppressive agents.

Morphological analysis of renal cell culture models of calcium phosphate stone formation

Cell culture models of calcium phosphate renal stone formation were established using the MDCK cell line. Renal microliths were detected within pseudocysts in three-dimensional soft agar cultures, and were also observed in the basal region of cells lining the cell sheet, and immediately beneath domes or blisters in monolayers and collagen gel cultures. Light and scanning electron microscopy indicated that these microliths had a similar lamellated and spherical appearance to those in humans. These microliths were first detected microscopically after 21 days of culture, and were found to be composed of calcium phosphate by X-ray and microinfrared spectroscopic analyses. These culture models may provide a powerful new tool to study the pathogenesis of renal stone diseases and/or calcium phosphate stone formation in humans and animals.

Laparoscopy-assisted radical nephrectomy without pneumoperitoneum.

A small renal cell carcinoma of the right kidney was completely removed from a 59-year-old women by laparoscopic radical nephrectomy without requiring a pneumoperitoneum. A 5-cm midline laparotomy incision was made and 3 small retractors were used for suspending the abdominal wall. Under laparoscopic observation, we safely positioned three trocars. The kidney was then removed en bloc together with the adrenal gland, perinephric fat and Gerotas fascia. The resected mass was enclosed in an entrapment sac and removed via the 5-cm abdominal incision without morcellation of the tissues. Three trocars could be positioned safely under direct observation and there were no adverse hemodynamic or ventilatory effects because the operation was performed without intraperitoneal carbon dioxide insufflation. There were no significant operative or postoperative complications. This procedure appears to be advantageous for the treatment of small renal cell carcinomas.

Hydronephrosis in ACI/N rats

Of 45 ACI/N rats 9 were found with renal agenesis and 2 with hydronephrosis. The hydronephrosis may have been due to faulty development of the mesonephric duct.

Microlith Formation In Vitro by Madin Darby Canine Kidney (MDCK) Cells

Background: The mechanism of renal stone genesis as well as the location of stone crystal formation in the kidney remains unclear. Possible sites of stone generation are either in the tubular lumen or tubular cell.

Expression of structure-specific recognition protein mRNA in fetal kidney and Fe-nitrilotriacetate-induced renal carcinoma in the rat

Specific expression of the structure-specific recognition protein (SSRP) gene was investigated in rat fetal, adult, and tumor tissues using a 2.0-kb partial sequence of rat SSRP cDNA isolated from a cDNA library of rat renal cell carcinoma. The results revealed that it was rather specifically expressed in rat fetal kidney and renal cell carcinoma induced by Fenitrilotriacetate, but not in adult kidney, when various organs were tested by Northern blot analysis. In situ hybridization further demonstrated that it was located in the neoplastic cells of renal cell carcinoma and in the epithelial cells of fetal kidney but undetectable in any cells of normal adult kidney. These observations seem to imply the involvement of SSRP gene, which is believed to recognize structural alterations of DNA, in kidney development and carcinogenesis of certain types of kidney cancer.