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T Terada

Publications and source records attributed to T Terada.

At least 343 records · Page 19Linked to original sources
PubMed1992

Antitumor agents. I. DNA topoisomerase II inhibitory activity and the structural relationship of podophyllotoxin derivatives as antitumor agents.

Various podophyllotoxin derivatives from desoxypodophyllotoxin (DPT) were synthesized to examine the structural relationships between the biological significance (cytotoxic effect, effects on DNA topoisomerase II and tubulin polymerization) in vitro and antitumor activity in vivo (L 1210). An intact 6,7-methylenedioxy group of DPT is necessary to inhibit tubulin polymerization and topoisomerase II. 4'-Phenolic hydroxyl group of DPT is essential to inhibit DNA topoisomerase II and the inhibitory effect on DNA topoisomerase II contributes to a high cytotoxicity. The introduction of an aminoalkoxy group at 1-position of DPT enhances the inhibitory activity against DNA topoisomerase II and cytotoxic effect, causing the inhibitory activity against tubulin polymerization to disappear. The results of antitumor test in mice bearing L 1210 on podophyllotoxin derivatives suggest the following: 1) the strong cytotoxic effect itself is not a good indication of antitumor activity in vivo as long as it is associated with inhibition of tubulin polymerization. DNA topoisomerase II inhibitory effect contributes to an antitumor activity in vivo; 2) detailed measurements of cytotoxicity and inhibition on DNA topoisomerase II and tubulin polymerization in vitro are necessary to evaluate podophyllotoxin derivatives.

Animals↗
PubMed1992

Multiple space-occupying lesions of the spleen in a case of Gaucher's disease.

A 50-year-old female patient was admitted because of an enormously enlarged spleen and thrombocytopenia. Ultrasonography and magnetic resonance imaging revealed multiple space-occupying lesions in the spleen. She was diagnosed as having Gaucher's disease based on the low level of beta-glucosidase activity in leukocytes and Gaucher's cells present in bone marrow aspirate. Severe hypersplenism necessitated splenectomy. Pathological studies of the excised spleen, including ultrastructural examinations, demonstrated that multiple space-occupying lesions in the spleen were composed of typical Gaucher cells.

Female↗
PubMed1992

Proliferative activity of bile duct epithelium after bacterial infection in dogs.

To clarify the relationship between proliferative activity in bile duct epithelia and bacterial infection in the dog, we induced obstructive cholestasis with a bacterial infection in two lobes of the liver. The bile duct branch draining the left lateral lobes of the liver was cannulated in all mongrel dogs. The dogs were divided into three groups and treated as follows: in group 1 the cannula was clamped after the injection of 10(7) Escherichia coli (aerobic bacteria) and 10(7) Bacteroides fragilis (anaerobic bacteria) cells; in group 2 the cannula was clamped after the injection of 10(7) E. coli cells; and in group 3 the cannula was clamped without the injection of any bacteria. Three months and 9 months later dogs from each group were killed, and their livers were examined. In the group 1 dogs papillary hyperplasia and severe dysplasia were noted in association with chronic cholangitis at 3 months and 9 months, respectively, after operation. In the group 2 dogs periductal fibrosis was severe, but epithelial papillary hyperplasia was less pronounced than in the group 1 dogs at each period. In the group 3 dogs no periductal fibrosis or epithelial papillary hyperplasia was seen at either 3 or 9 months postoperatively. These findings suggest that papillary hyperplasia and/or severe dysplasia of the bile duct epithelium may be caused by aerobic and anaerobic bacterial infection of the biliary tract in combination with bile stasis.

Animals↗
PubMed1992

[Trial of in vitro fertilization via epididymal duct aspirated sperm].

We made a trial of our method by which sperm are collected directly from epididymal duct, then subjected to in vitro fertilization. The subjects were a total of 22 cases comprising 14 of obstructed azoospermia and 8 of severe oligoasthenozoospermia, on which the surgery was performed 26 times. Using the microscope, an epididymal duct was directly punctured to make a suction of the fluid or was slightly incised to make a suction of the outflow. Sperms thus collected were preincubated for 4 to 6 hours, then subjected to in vitro fertilization. Condition of collected sperms; 32 x 10(4)-15300 x 10(4) sperms were obtained in real number. Sperm motility rate was 0-82%, averaging 25.0%. Sperm forward motility were fairly good in 18 of 26 test cases. Sperm condition was so poor as to make the insemination impossible in 4 test cases (16%). Fertility rate for cases of obstructed azoospermia was 53% (8/15 test cases) and 63% (55/87 eggs) in the test cases and the number of eggs, respectively, compared with 33% (2/6 test cases) and 5.4% (2/37 eggs), respectively for cases of oligo-asthenozoospermia. Pregnancy; Successful pregnancy was obtained in 2 of the cases of obstructed azoospermia, in each of which sperms were collected from the head of the epididymis, then passed into the maternal body by zygote intra fallopian tubal transfer (ZIFT); with the one case resulting in uneventful delivery in November 1991 and the other in a miscarriage. The above results suggested the present method would become an epoch-making approach in the treatment of severe male infertility.

Epididymis↗
PubMed1992

Ultrasound visualization of hepatic peribiliary cysts: a comparison with morphology.

We report herein a hitherto unrecognized, interesting ultrasound finding ("hilar multicystic echo complex"), the result of peribiliary cysts in the liver. This ultrasound finding was discovered around intrahepatic large bile ducts and large portal vein branches near the hepatic hilum in an autopsy case with hepatocellular carcinoma, submassive hepatic necrosis superimposed on chronic active hepatitis, and portal hypertension. Antemortem ultrasound examination revealed the hilar multicystic echo complex around the portal venous branches near the hepatic hilum. Autopsy confirmed that the hilar multicystic echo complex was due to peribiliary cysts that were present around the bile ducts at the hilum. The peribiliary cysts were thought to have arisen from cystic dilatation of preexisting intrahepatic peribiliary glands. These peribiliary cysts reportedly occur in livers with portal hypertension (e.g., cirrhosis, hepatocellular carcinoma, idiopathic portal hypertension, extrahepatic portal obstruction, and portal thromboembolism), adult-type polycystic disease of the liver and kidneys, and systemic infection. Therefore, recognition of peribiliary cysts at sonography would have diagnostic value, and may indicate that presence of one of the above described liver diseases.

Adult↗
PubMed1992

Extensive portal tumor thrombi with portal hypertension in an autopsy case of intrahepatic cholangiocarcinoma.

Vascular invasion is not a prominent feature of cholangiocarcinoma (CCC), in contrast to hepatocellular carcinoma (HCC), which frequently shows extensive vascular tumor thrombi. We report an autopsy case of CCC with extensive portal tumor thrombi and portal hypertension. A 57-yr-old man presented with abdominal pain. Liver imaging revealed no tumors, but showed intrahepatic portal venous obstruction. HCC with portal tumor thrombi was suspected clinically. His clinical course was rapid; he died of hepatic failure 50 days after admission. At autopsy, the liver (2,700 g) was studded with diffuse whitish yellow granular areas with flecks of coalescent granules. Intrahepatic portal veins were diffusely occluded by tumor thrombi. Microscopically, the tumor was poorly differentiated adenocarcinoma with mucin; tumor cells were immunohistochemically positive for carcinoembryonic antigen, CA 19-9, DU-PAN-2, and biliary type cytokeratins, but negative for alpha-fetoprotein. Tumor cells were diffuse in the liver, and there were numerous tumor thrombi in the small portal veins. Hepatic veins and small arteries were occasionally occluded by tumor thrombi. There was ascites, splenomegaly and tumor thrombi in the gastric and esophageal veins, suggesting that portal hypertension had been present. This tumor seemed to have marked affinity to invade portal veins. It must be stressed that there are CCCs with extensive portal tumor thrombi and resultant portal hypertension.

Adenoma, Bile Duct↗
PubMed1992

[A case of giant prostatic calculi].

A 83-year-old man was admitted because of fever and painful swelling of the right scrotal contents on January 23, 1989. Kidney-ureter-bladder X-ray (KUB) showed multiple big prostatic calculi which were compressed postero-laterally by benign prostate hyperplasia (BPH) according to the CT film. UCG film revealed urethral stricture in the anterior urethra. He was diagnosed as having right epididymitis, urethral stricture, BPH and giant prostatic calculi. He was treated with right orchiectomy, urethral bougie and suprapubic prostatectomy with removal of the calculi. The total weight of the prostatic calculi was 28 g of consisted of 125 pieces. The postoperative course was uneventful and two years after the operation he has been well and free from evident disease.

Aged↗
PubMed1992

[A study on the mass screening system for prostatic diseases].

Between 1984 and 1990, a mass screening for prostatic diseases was carried out on men over 55 years old in cities, towns and villages in Toyama Prefecture, Japan. The total number of subjects examined in the primary study was 1,232, which was 17.7% of the males over 55 years old in these areas. The primary study consisted of inquiry concerning urination, digital examination of the prostate, transabdominal ultrasonography, and determination of tumor markers. A secondary study was indicated for 100 subjects (8.9%) suspected to have prostatic cancer and 169 (15%) suspected to have benign prostatic hypertrophy, but only 92 (35%) of them were actually examined. Prostatic cancer was histologically diagnosed in 3 subjects (0.3%), and benign prostatic hypertrophy was established in 56 subjects (4.5%), who were referred to urologists. Though a high percentage of the population was covered by the primary study the percentage of subjects who received the secondary study among those in whom it was indicated was low. This probably was a reason for the low detection rate of prostatic cancer. An improved system is considered to be needed to increase the efficiency of mass screening for prostatic diseases.

Humans↗
PubMed1992

[Pitfalls of endovascular treatment for cerebral aneurysms].

Seventeen cases of unclippable aneurysms were treated by the endovascular balloon technique. Nine of them involved the anterior circulation, and eight involved the posterior circulation. Eleven of them were treated by parent artery occlusion with detachable balloons. Three were treated by endosaccular balloon embolization, and three cases combined with AVMs were occluded using ethylene vinyl alcohol copolymer (EVAL) including feeding arteries of the AVMs. Embolic complications occurred in one case of an IC bifurcation giant aneurysm treated by parent artery occlusion. Ischemic complications also appeared in two cases of aneurysms treated by endosaccular balloon embolization. In one case, the thrombus in the aneurysm propagated into the parent artery and occluded it later. In another case, the displaced balloon had obliterated the parent artery 6 hours after the embolization. Parent artery occlusion is a safe way to treat internal carotid giant aneurysms. However, endosaccular treatment still has some problems, i.e., 1) maintaining the balloon's position to preserve the parent artery, 2) balloon migration into the clot, 3) rupture of the aneurysm during or after treatment. Our studies indicate that endosaccular balloon embolization is still a high risk procedure and should be used only in selected cases, until new embolic agents, such as detachable coils, become available.

Adult↗
PubMed1992

The "duct-ectatic" variant of mucinous cystic neoplasm of the pancreas: clinical and radiologic studies of seven cases.

Seven cases of the "duct-ectatic" variant of mucinous cystic neoplasm of the pancreas are presented. This new entity, the duct-ectatic variant of mucinous cystic neoplasm of the pancreas, probably masquerades as pancreatic pseudocyst clinically and radiologically. However, it has the characteristic pathologic findings of the classic "megacystic" type of mucinous cystic neoplasm. If there are cysts visualized on pancreaticogram which are in a diffusely duct-ectatic configuration and are in communication with the main pancreatic duct, the duct-ectatic variant of mucinous cystic neoplasm should be strongly suspected rather than the pancreatic pseudocyst.

Adult↗
PubMed1992

Glutathione S-transferase isozymes in rat lens.

Rat lens contains two classes of glutathione S-transferase (GST) isozymes; one is class mu, Yb1-Yb1, and the other is class pi, Yp-Yp, judged from their molecular weights, immunological properties and N-terminal amino acid sequences. The expression pattern of GST isozymes in the rat lens is different from that in pig and bovine lenses which have only class pi and class mu isozymes, respectively.

Amino Acid Sequence↗
PubMed1991

Pig lens glutathione S-transferase belongs to class Pi enzyme.

Class Pi glutathione S-transferase was purified to homogeneity from pig lens cytosol. This enzyme was composed of two identical 22 kDa subunits and had isoelectric point of 8.5 from the results of SDS gel electrophoresis, gel filtration, amino acid sequence analysis and isoelectric focusing. Amino acid sequence of N-terminal 15 residues was almost identical to class Pi enzymes from human, rat and mouse. Antibody against the pig enzyme crossreacted to human glutathione S-transferase-pi and anti-rat glutathione S-transferase-P antibody crossreacted to pig enzyme.

Amino Acid Sequence↗
PubMed1991

Improved methods for purification of an enterotoxin produced by Bacillus cereus.

An enterotoxin (ET) produced by Bacillus cereus was purified by ammonium sulfate precipitation followed by chromatography on SP-Sephadex C-25, chromatofocusing, and gel filtration on Sephacryl S-300. Purified ET was electrophoretically homogeneous with a molecular mass of 45,000 and with an isoelectric point of 5.5. It showed vascular permeability activity in rabbits, was lethal to mice, and caused fluid accumulation in mouse ligated intestinal loops. It showed cytotoxicity to Vero cells, but did not show any hemolytic or phospholipase C activities. These biological activities were found to be easily inactivated by heating at 56 degrees C for 5 min, by digestion with trypsin and pepsin, and by exposure to pH below 3.0 or higher than 11.

Animals↗
PubMed1991

Inactivation of human placenta glutathione S-transferase by SH/SS exchange reaction with biological disulfides.

The oxidized glutathione inhibited the activity of glutathione S-transferase purified from human placenta just through competitive inhibition. On the other hand, cystine and cystamine inactivated the activity by pseudo first-order in low concentrations, accompanying the stoichiometric incorporation of the radioactivity of [14C]-cystine to the enzyme protein until a half mole per one subunit. This and the protective effect of glutathione analogues suggested that the SH/SS exchange reaction occurred between the disulfide and the SH group near the glutathione binding site of the enzyme to form a mixed disulfide.

Cystine↗