Kaiso Sano

Modulation of Membrane Permeability, Cell Proliferation and Cytotoxicity of Antitumor Agents by External ATP in Mouse Tumor Cells

External ATP causes a remarkable change in the passive permeability of the plasma membrane in several types of transformed cells. When mouse melanoma cells, Clone‐M3, were exposed to ATP in Tris‐buffered saline, a great increase in the passive permeability was induced within several minutes. Longer exposure of Clone‐M3 cells to external ATP led to a decrease in cell viability. Similar results were obtained with Ehrlich ascites cells, but none of these ATP effects were noted in untransformed cells such as NIH 3T3 cells or BALB/c mouse embryonic fibroblasts. The in vitro cytotoxic effects of antitumor agents (5‐fluorouracil, adriamycin, mitomicin C and nimustine hydrochloride) against Clone‐M3 cells were additively potentiated by treatment with external ATP, which also synergistically enhanced the cytotoxicity of vincristine. However, the effects of these drugs on mouse embryonic fibroblasts were not modulated by ATP. These results suggest that ATP‐treatment is a useful means of enhancing a selective toxicity for tumor cells.

Duodenal atresia secondary to intrauterine midgut strangulation by an omphalocele

Presented here is the first instance of duodenal atresia due to intrauterine midgut strangulation and necrosis in a tight omphalocele defect in a newborn infant with myelomeningocele and hypoplasia of both lower extremities.

Cryosurgical hemorrhoidectomy: How to prevent the postoperative swelling and prolapse

Cryosurgical hemorrhoidectomy was performed on 171 patients with excellent results achieved in the great majority. The key to successful results is based on the prevention of prolapse of the edematous tissue after freezing. To prevent the edema, it is important to pull out the hemorrhoid as much as possible during the freezing, to freeze only on the rectal side of the anal verge, to carefully avoid freezing the anal verge, and to freeze the hemorrhoids in two or three stages when they are large. Less than satisfactory results were achieved in 11.7% of the patients. The anal discomfort and discharge in these patients were related to prolapse of the frozen tissue. Cryosurgery is an effective method of treatment for hemorrhoids if care is taken to use the proper technique.

Local Recurrence After Local Excision of Early Rectal Cancer

The advantage of local excision for early rectal cancer, excluding fiberscopic polypectomy, is that it allows preservation of the anal function of the sphincter. We treated 75 patients with early rectal cancer and carried out local excision in 29 of these cases during the period from 1974 to 1992. Three of these 29 patients were reoperated upon immediately because of massive invasion to the submucosa at the margin of the removed specimen. Two other cases experienced local recurrences and required additional surgery.

Cryosurgical Treatment For Local Recurrence Of Rectal Cancer

During the last 19 years we have used cryosurgery as part of a multidisciplinary therapy to treat 12 patients with local recurrence of rectal cancer. This treatment was chosen to provide these patients with the palliative benefits of minimal bleeding and to reduce tumor bulk. The survival time following resection therapy in 30 cases after relapse was significantly greater than that for the 12 cases receiving cryosurgical treatment. However, local destruction of the recurring cancer by cryosurgery resulted in effective control of the tumor.

A Nodule‐aggregating Lesion of the Rectum Associated with Gastric Adenoma —A Case Report—

Abstract: A 81‐year‐old female was admitted to our hospital to undergo endoscopical treatment for a gastric adenoma and received YAG‐laser therapy. The gastric adenoma was completely removed by laser therapy. However, following treatment, she complained of having mucous feces. Although she had undergone a colonoscopy twice during the previous six month, we examined her large intestine using colonoscopy and barium enema. A colonoscopy revealed a large‐flat elevated lesion of the same color as the surrounding mucosa and no transmucosal vascularity of the rectum. A well demarcated flat lesion 4 cm in size with conglomerated nodules on its surface was confirmed using the dye‐spraying contrast method with 0.2% indigo carmine solution. A lower anterior resection of the rectal lesion was performed and the patient is now living and well 16 month following surgery. We believe that, if we encounter gastric adenomas, more careful observation and use of the dye‐spraying contrast method are necessary for the detection of adenomas or cancers in the colon.