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K J Cho

Publications and source records attributed to K J Cho.

188 records · Page 11Linked to original sources
PubMedDate not supplied

Inhibitory effects of biochanin A on benzo(a)pyrene induced carcinogenesis in mice.

Biochanin A was studied for its capacity to inhibit benzo(a)pyrene (BP) induced neoplasia in female Swiss Webster mice. To investigate the effect of biochanin A on the initiation step, biochanin A (500 mg/kg) was administered orally 48 hours prior to BP (3 mg/mouse), which was also given orally. This sequence of biochanin A and BP administration was repeated once a week for a total of 4 weeks. At 26 weeks after the last treatment, all the mice were sacrificed. To investigate the effect of biochanin A on the promotion step, a single subcutaneous injection of 0.5 mg of BP was given within 24 hours after birth, and biochanin A (0.125 mg/mouse) was injected intraperitoneally 3 times a week for 6 weeks after weaning. In the initiation protocol, the concomitant administration of biochanin A showed significant inhibition of the mean number of lung tumors (P less than 0.001) and the incidence of carcinoma of the forestomach (P less than 0.02). In the promotion protocol, biochanin A significantly inhibited the incidence (P less than 0.01) and the multiplicity (P less than 0.001) of pulmonary adenoma, compared with the group treated with BP alone. These results suggest that biochanin A inhibitory potential in the initiation, as well as in the promotion step of BP carcinogenesis in female Swiss-Webster mice.

Adenoma↗
PubMedDate not supplied

Effusion cytology of endodermal sinus tumor of the colon. Report of a case.

A three-year-old boy presented with a peritoneal effusion due to an occult endodermal sinus tumor in the ascending colon. Cytologic examination of the ascitic fluid revealed clusters of round plump cells that had large hyperchromatic nuclei, finely stippled chromatin, multiple prominent nucleoli and vacuolated or mucin-containing cytoplasm, features suggesting an adenocarcinoma. The colonic primary was discovered during emergency laparotomy performed due to suspected acute hemoperitoneum. Endodermal sinus tumor should be included in the differential diagnosis when cytologic features reminiscent of adenocarcinoma are encountered in a fluid specimen from a child, especially if there is a history of a gonadal or extragonadal childhood neoplasm.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Limitations of percutaneous insertion of Greenfield filters.

Although it is technically possible to insert the standard stainless steel Greenfield filter (SGF) percutaneously using a 24 Fr. sheath, the incidence of insertion site venous thrombosis and the advantages of percutaneous technique have prompted the development of a titanium Greenfield filter (TGF) which can be inserted percutaneously through a 14 Fr. sheath or operatively. Clinical experience in 52 patients resulted in 51 placements (98%) with the majority below the renal veins (90%). One technical error resulted in caval penetration by the apex of the TGF without sequelae. One of the 19 deaths postinsertion was attributed to recurrent thromboembolism, and there was one additional event for a 4% recurrent embolism rate. At follow-up of 30 patients, averaging 5.2 months, all filters were patent and there were no proximal migrations. However, there was distal migration of 9-64 mm in 9 patients (30%) and tilting which increased from 8 patients at insertion to 12 at follow-up. Insertion site venous thrombosis occurred in 2 patients (7%) who were asymptomatic. Filter leg penetration of the vena cava was suspected in 9 patients (30%), but there were no clinical sequelae from this or the distal migrations. Since the clinical results of the TGF are comparable to the SGF, modifications of hook design should correct the tendency for wall penetration and distal migration.

Adolescent↗
PubMedDate not supplied

Effects of allyl sulfide, germanium and NaCl on the development of glutathion S-transferase P-positive rat hepatic foci initiated by diethylnitrosamine.

The modification potentials of allyl sulfide, germanium and NaCl on the development of preneoplastic hepatic enzyme altered foci were examined in an in vivo mid-term assay system. Rats were initially given a single dose (200 mg/kg), intraperitoneal injection of diethylnitrosamine (DEN) and, starting 2 weeks later, were treated with allyl sulfide, germanium and NaCl at a concentration of 0.5%, 0.05% and 5%, respectively, in the diet for 6 weeks and then killed. All rats were subjected to two-thirds partial hepatectomy at week 3. The modifying potential was scored by comparing the number and area per cm2 of induced glutathione S-transferase placental form-positive (GST-P+) foci in the liver with those of the corresponding control group given DEN alone. Allyl sulfide exerted an obvious inhibition of the development of GST-P+ foci as regards both number and area. On the contrary, germanium showed a significant increase in the number of GST-P+ foci, although the data for area were not altered. NaCl had no modifying effect on their development.

Allyl Compounds↗
PubMedDate not supplied

Visualization of time-dependent inactivation of human tumor cathepsin B isozymes by a peptidyl fluoromethyl ketone using a fluorescent print technique.

A peptidyl fluoromethyl ketone (Z-Phe-Ala CH2F) was found to be an effective compound in a time dependent inactivation of cathepsin B isozymes from a number of tissues including human tumors. The effect was visualized by employing an activity-specific fluorescent print technique preceded by isoelectric focusing. The technique could yield additional information of selective inhibition of isozymes as observed with rat pancreas. The fluoromethyl ketone is 30-fold more potent than the known inhibitor of cathepsin B, Z-Phe-AlaCHN2 in parallel evaluation. Furthermore, the fluoromethyl ketone may have in vivo potential in the inhibition of cathepsin B, in view of the results of toxicological studies. The findings demonstrate that the application of enzyme-directed overlay membranes, impregnated with specific substrates, following isoelectric focusing could be very useful in the study of proteases and their involvement in the oncogenic process.

Animals↗
PubMedDate not supplied

Effects of experimental embolization of superior mesenteric artery branch on the intestine.

A primary mesenteric branch of the superior mesenteric artery was embolized with Amicar-mixed clots in seven dogs and with gelatin sponges in five dogs. All of the dogs embolized with Amicar-mixed clots survived the experimental period and no mesenteric damage was found with postmortem studies. Three of the five dogs embolized with gelatin sponges showed a local stricture within the embolized segment of intestine. Collateral blood supply to the strictured segment of bowel in these three dogs developed via arterial arcades, mural branches of the vasa recta and omental arteries.

Aminocaproates↗
PubMedDate not supplied

Rhabdomyosarcoma of the head and neck in adults: MR and CT findings.

PURPOSE: To evaluate imaging findings of rhabdomyosarcoma of the head and neck in adults. METHODS: We examined 11 patients (seven men and four women; 17 to 73 years old) with pathologically proved rhabdomyosarcoma of the head and neck. The tumors originated in the paranasal sinuses (n = 6), cheek (n = 3), nasal cavity (n = 1), and infratemporal fossa (n = 1). Eight of the rhabdomyosarcomas were of the embryonal type, two were pleomorphic, and one was alveolar. Necrosis was seen in four patients, but calcification or intratumoral hemorrhage was not found. Two tumors had nodal extension. Contrast-enhanced CT was performed in 10 patients, and two patients had contrast-enhanced MR imaging. RESULTS: On CT scans, the masses enhanced to the same degree as adjacent muscle. The masses showed a homogeneous pattern in six cases and a heterogeneous pattern in four cases. The tumor margins were poorly defined in eight cases. On MR images, the masses were homogeneously isointense with muscle on T1-weighted studies and were hyperintense relative to muscle on T2-weighted studies. On both CT and MR images, 10 of 11 cases showed poorly defined, homogeneous masses destroying adjacent bony structures. CONCLUSIONS: MR imaging seems to be better than CT for initial and follow-up examination of patients with rhabdomyosarcoma because of its multiplanar capability and because it more precisely defines the extent of tumor.

Adolescent↗