Biomedical subjects

K Kuroda

Publications and source records attributed to K Kuroda.

582 records · Page 33Linked to original sources

PubMedDate not supplied

Studies on interactions between traditional herbal and Western medicines. IV: lack of pharmacokinetic interactions between Saiko-ka-ryukotsu-borei-to and carbamazepine in rats.

The possibility of pharmacokinetic interactions between Saiko-ka-ryukotsu-borei-to extract powder (TJ-12), a widely used traditional Chinese herbal (Kampo) medicine, and carbamazepine (CBZ), an important anti-epileptic drug, was examined in rats. There were no significant differences in the serum protein binding of CBZ and carbamazepine- 10,11-epoxide (CBZ-E), its active metabolite, at two concentrations (1 and 10 Bg/ml) between twogroups pretreated orally with the vehicle andTJ-12 suspension (1 g/kg/d, p.o.) for 1 week. One-week repeated pretreatment with TJ- 12 (1 g/kg/d) did not influence liver weight, contents of cytochromes P450 and b5 in hepatic microsomes or the formation rate of CBZ-E from CBZ by its microsomes, while pretreatment with phenobarbital (80 mg/kg/d, i.p.) significantly increased these parameters. Neither a single nor 1-week repeated oral pretreatment with TJ-12 (1 g/kg/d) affected the plasma concentration-time profile and any pharmacokinetic parameter of CBZ or CBZ-E after oral administration of CBZ (50 mg/kg). These results indicated that oral co-administration of TJ-12 with CBZ has no effect ofthe pharmacokinetics of CBZ or CBZ-E in rats. Concomitant treatment with TJ- 12 and CBZ appears to be pharmacokinetically safe in humans.

Animals↗

PubMedDate not supplied

Mutagenicity and DNA-damaging activity of decomposed products of food colours under UV irradiation.

Five synthetic food colours Food Red Nos 3, 40 and 102 and Food Blue Nos 1 and 2, and their UV irradiated products were tested for mutagenic activity by means of the Ames test using Salmonella typhimurium strains TA98 and TA100. Food colours were irradiated with UV light for 14 days. Food Red Nos 3, 40 and 102 and Food Blue No. 1 were non-mutagenic before and after irradiation. UV irradiated products of Food Blue No. 2 were mutagenic in TA98 with or without S-9 mix. The mutagenic activity increased with increasing irradiation period, reached maximum potency on day 6, and then decreased. Moreover, Food Blue No. 2 showed DNA-damaging activity after 14 days of irradiation in rec-assay using Bacillus subtilis strains H17 and M45. The capillary electrophoresis was applied for the analysis of UV irradiated products of Food Blue No. 2. The original peak of Food Blue No. 2 was decomposed into seven peaks after UV irradiation.

Bacillus subtilis↗

PubMedDate not supplied

Intrathecal administration of thrombin inhibitor ameliorates cerebral vasospasm. Use of a drug delivery system releasing hirudin.

The role of thrombin as a spasmogen after subarachnoid hemorrhage was evaluated using the intrathecally administered thrombin inhibitor hirudin, released from a drug delivery system (DDS) based on collagen in a canine vasospasm model. The DDS was implanted into the cisterna magna with autologous blood in the hirudin-treated group. The reduction in the angiographical diameter of the basilar artery was only 19% in the hirudin-treated group on day 7, showing a significant difference between hirudin-treated and nontreated groups (p < 0.01). These results suggest that thrombin is an important cause of vasospasm. The collagen DDS has great potential for treatment in the cerebrospinal fluid milieu.

Animals↗

PubMedDate not supplied

[A case of the cerebellar atrophy and pseudo-hyperchloremia as a clue to diagnose chronic bromvalerylurea intoxication].

A 36-year-old woman was admitted to our hospital because of walking disturbance and dizziness. Her neurological examination showed psychiatric disturbance, truncal and limb ataxia, wide-based gait. She has taken 3 g of bromvalerylurea daily. The laboratory test revealed elevated levels of serum chloride (201 mEq/L) and bromide (105 mg/dl), and decreased (-43 mEq/L) anion gap. Brain MRI revealed atrophy of upper part of the vermis and cerebellar hemisphere, and widening of the primary fissure and dilatation of the forth ventricle. Bromvalerylurea, which is an easily available sedative, should be still noted as a cause of cerebellar ataxia. Increased level of serum chloride was useful information for early diagnosis of chronic bromide intoxication.

Adult↗

PubMedDate not supplied

Primary round cell liposarcoma of the omentum. A case report.

Liposarcomas are the most common of the malignant soft tissue tumors arising in the mediastinum and retroperitoneum. We have treated patients for round cell liposarcoma, an unusual histologic subtype, which is reported to be histologically mistaken for Ewing's sarcoma, lymphoma and other round cell neoplasms. The successful resection of a 2,300-g round cell liposarcoma of the omentum was recently performed at our hospital. Ultrastructural observations of this tumor are characterized by massive proliferation of the mitochondria in addition to the presence of lipid vacuoles in tumor cells. To our knowledge, no description of substantial mitochondrial proliferation in round cell liposarcoma has appeared previously in the literature; therefore, this is the first case report of histopathologic, cytopathologic and electron microscopic observations on this extremely rare tumor.

Female↗

PubMedDate not supplied

The inhibitory effect of selenium on induction of tetraploidy by dimethylarsinic acid in Chinese hamster cells.

Arsenic is a human carcinogen. On the other hand, selenium supplementation can inhibit induction of carcinogenesis by chemical carcinogens. The effect of selenium compounds on the cytotoxicity of dimethylarsinic acid (DMA) and on the induction of tetraploidy by DMA were studied using Chinese hamster V79 cells. Two selenium compounds were tested, sodium selenite and trimethylselenonium iodide (TMSeI). Trimethylselenonium is a major excretory product of selenite metabolism. The cytotoxicity of sodium selenite was 1000-fold greater than that of TMSeI. The cytotoxicity of DMA was about the same as that of TMSeI. The mitotic index for DMA administration was increased by these selenium compounds at low concentrations and decreased by them at high concentrations. The tetraploid index for DMA decreased with increasing concentrations of these selenium compounds. Tetraploidy is a form of aneuploidy, and aneuploidy is known to induce carcinogenesis. The finding that selenium inhibited induction of tetraploidy by DMA may yield clues to the role of selenium in the chemoprevention of carcinogenesis by chemical carcinogens.

Aneuploidy↗