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K Taira

Publications and source records attributed to K Taira.

277 records · Page 16Linked to original sources

Radioimmunoassay for dexamethasone 17,21-dipropionate and its metabolites in plasma and urine after topical application.

A sensitive radioimmunoassay for dexamethasone 17,21-dipropionate and its four metabolites in human plasma and urine has been developed using single anti-dexamethasone antiserum. The antiserum was obtained by immunizing rabbits with dexamethasone-3-oxime-bovine serum albumin conjugate. All of the endogenous steroids tested cross-reacted less than 0.07%. Before radioimmunoassay, dexamethasone 17,21-dipropionate and dexamethasone 17-propionate were hydrolyzed to dexamethasone, and 6 beta-OH-dexamethasone 17-propionate was hydrolyzed to 6 beta-OH-dexamethasone in 3% ammonia/methanol at 5 C for 16 h. A standard curve was established with a useful range between 0.005 and 2 ng in the case of dexamethasone, between 0.05 and 5 ng in the case of 6 beta-OH-dexamethasone. Measurement of plasma concentrations and percent urinary excretion of the metabolites in healthy men was performed following occlusive dressing of dexamethasone 17,21-dipropionate cream and ointment. The main metabolites in plasma were dexamethasone 17-propionate and dexamethasone, which increased gradually and reached maximum levels (160-200 pg/mL) at 24-32 h after application. The major metabolites observed in urine were 6 beta-OH-dexamethasone 17-propionate and 6 beta-OH-dexamethasone. Total percentage of their urinary excretions within 72 h after application amounted to 0.28-0.50% of the dose administered.

Administration, Topical↗

Role of the Fas system in liver regeneration after a partial hepatectomy in rats.

Apoptosis is involved in the homeostatic control of organs. The aim of this study was to define the in vivo role of apoptosis-related proteins including the Fas system and Bcl-2 in liver regeneration following a partial hepatectomy (PH). We used 70% hepatectomized rats which were serially sacrificed from 12 h to 28 days. The expressions of Fas, Fas ligand, and Bcl-2 were examined by semiquantitative RT-PCR and immunohistochemistry. Liver regeneration, as examined by PCNA staining, peaked from 24 h to day 3, and declined from day 5. On the other hand, hepatocyte apoptosis, as examined by TUNEL staining, was seldom observed until 24 h, but increased from 1 week after PH. In the RT-PCR study, Fas showed an early decline by 24 h, followed by a later peak from days 3 to 5, and then a constant expression thereafter. Meanwhile, the Fas ligand was also low until day 3, but showed a remarkable increase from days 5 to 7, followed by a gradual decrease. On the other hand, Bcl-2 showed an early peak until 24 h, followed by a decline from day 5. In an immunohistochemical study, the time courses of these protein expressions were almost synchronous with their mRNAs in the RT-PCR study. We thus conclude that the coordinated interplay between these apoptosis-related proteins and hepatocyte apoptosis suggests the possible involvement of these proteins in the course of liver regeneration.

Animals↗

Resection of triple synchronous cancers: a case report.

We herein present a case of synchronous triple cancer, which was successfully resected in a curative manner. These cancers consisted of primary duodenal, pancreatic and lung cancers, which were diagnosed in an asymptomatic 74 year-old male, who was referred to our department on December 14, 1996. On admission, his laboratory data showed no abnormality, including tumor markers (CEA 1.0, CA 19-9 1.0, AFP 8.1 U/ml), but he did show an impaired pulmonary function (FEV1.0: 57%). Upper gastrointestinal endoscopy showed a smooth surfaced duodenal tumor measuring 4 cm in size. The second tumor was found at the head of the pancreas by computed tomography (CT), showing a hypervascular mass measuring 3.0 cm, along with neighboring multiple cysts. In endoscopic retrograde cholangiopancreatography (ERCP), marked mucous secretion was observed through the papilla, while a filling defect was found in the dilated pancreatic duct. In a routine chest X-ray, a third tumor, which measured 1.5 cm in diameter, was recognized in the right upper lobe of the lung, and a moderately differentiated squamous cell carcinoma was also detected by a percutaneous CT guided biopsy. The pancreatic and duodenal tumors were surgically resected by a pancreatoduodenectomy (Stage I) in January 1997 and, 5 months later, a lung tumor underwent partial resection (Stage I). This patient tolerated these surgical procedures well and presently leads a normal, healthy life after discharge. In summary, a successful resection of synchronous triple cancers, which has never been previously reported in this specific combination, is described.

Adenocarcinoma↗