An enzyme immunoassay (EIA) has been developed for determination of 6-amino-5-chloro-1-isopropyl-2-(4-methyl-1-piperazinyl) benzimidazole (KB-6806), a novel 5-HT₃ receptor antagonist. Anti-KB-6806 antiserum was elicited against the KB-6806-bovine serum albumin (BSA) conjugate prepared by a diazo coupling reaction through the inherent 6-amino group. β-Galactosidase-labeled 6-amino-5-chloro-1-isobutyl-2-(4-methyl-1-piperazinyl)benzimidazole was similarly prepared by diazo coupling reaction as an enzyme-labeled antigen with a hapten heterologous combination of antiserum. The modification at the 4-methyl group of the piperazine moiety of KB-6806 significantly decreased the binding affinity to the antibody. This method could quantitate KB-6806 in dog plasma in the concentration range of 0.078-10 ng/ml with good accuracy and precision. The EIA method has been successfully applied to the determination of KB-6806 in plasma after intravenous administration of KB-6806 to dogs.

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Synthetic decarboxylated S-adenosyl-L-methionine (dcAdoMet), a mixture of the absolute configuration of S and R at the sulfonium center, was evaluated as a substrate for the measurement of spermidine synthase activity. The diastereomers were separated by HPLC with an isocratic elution, and the constant for racemization at the sulfur was determined to be 2.4×10⁻⁶ s⁻¹ at 37 °C and pH 1.5 for the first-eluted biologically active isomer (S-dcAdoMet) and 2.0×10⁻⁶ s⁻¹ for the second-eluted biologically inactive isomer (R-dcAdoMet). The peak area ratio of S-dcAdoMet to R-dcAdoMet of 48 to 52 in HPLC supported the different racemization constants. Similar substrate activity of dcAdoMet to that of S-dcAdoMet was demonstrated by enzymatic spermidine synthesis. It was shown from the result that the racemized [methyl-¹⁴C]dcAdoMet prepared in this report was useful for measuring spermidine synthase activity.

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きれいな球状をした緑藻ボルボックスは，生物の教科書にもよく掲載されており，名前と形を連想できる方は多いかもしれない．現在，モデル生物としてゲノム配列の解析が行なわれているボルボックスの発見は，レーウェンフックまで遡る．ここでは，この種の研究の歴史と生活環を紹介し，そしてボルボックス胚の形態形成運動の分子機構について紹介する．

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従来の古典力場では，r^-12^項とr^-6^項からなる12-6 Lennard-Jones (LJ)モデルが用いられてきた．しかし，このモデルは，電荷-誘起双極子，双極子-誘起双極子間相互作用を考慮していないため，金属蛋白質における金属イオンの配位構造を正確に表現できない．最近，この欠点を克服するため，12-6 LJモデルにr^-4^項を加えた12-6-4 LJモデルが提案された．本研究では，12-6-4 LJモデルと12-6 LJモデルを用いて，金属蛋白質の構造と結合自由エネルギーを計算し，両モデルを比較する．

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  This review describes my work in the field of polyamine research for the last 35 years. My research started with developing the improved synthesis of decarboxylated S-adenosylmethionine and then moved to the purification of spermidine synthase from rat prostate. I also took considerable efforts to find the synthetic procedure for various polyamines with high yield in order to prepare ¹⁵N-labeled polyamines. On the basis of these methodological work, I searched for the inhibitor of spermidine synthase and found trans-4-methylcyclohexylamine (MCHA), the most effective one at the present time. I also developed a new analytical method for polyamines using stable isotope and ionspray ionization mass spectrometry (IS-MS). Based on these studies I examined the role of polyamines in liver regeneration and found that oral administration of MCHA effectively changed the concentration of polyamines and inhibited the hepatic growth. I also found the close relationship between the concentration ratio of spermidine to spermine and the extent of liver regeneration. These results may shed new light on the control of cell growth by polyamine in vivo.

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We have previously shown that abnormally fast sedimenting DNA which accumulates upon infection of mutants of T4 phage defective in gene 49 is recombination intermediates, while the mutant gives rise to the recombination deficient phenotype, judging from genetic mating tests under the semipermissible condition (Minagawa and Ryo (1979) Mol, gen. Genet. 170: 113; Minagawa et al. (1983a) Virology 126:138; Miyazaki et al. (1983) Genetics 104:1). To see the step to which the recombination process has proceeded in the DNA, we investigated by the transfection assay whether the generation of contiguous recombinant strands is completed. Such strands were found to be formed normally or nearly normally in the absence of the gene 49 function, supporting the view that the gene product is involved in resolution of branched recombinational intermediates into linear duplexes.

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Several studies have suggested that high blood pressure is associated with the risk of bone loss. Since various antihypertensive drugs are in wide use for the treatment of hypertension, it is important to investigate the influences of these drugs on bone metabolism. Osteoblasts play a pivotal role in the regulation of bone formation. During differentiation, they sequentially express type I collagen, alkaline phosphatase (ALP), other bone matrix proteins, and finally undergo mineral deposition. In this study, we examined the effects of various antihypertensive drugs on the function of osteoblast using clonal MC3T3-E1 cells. Drugs examined include dihydropyridine-type calcium channel blockers (benidipine, amlodipine, and nifedipine), angiotensin-converting enzyme (ACE) inhibitors (captopril, lisinopril, and enalapril), and angiotensin II receptor type1 (AT1) antagonists (TCV-116 and KW-3433). None of the ACE inhibitors or AT1 antagonists affected ALP activity or cellular DNA content significantly. In contrast, benidipine, amlodipine, and nifedipine increased ALP activity when used in amounts 1 pM, 100 nM, and 100 nM, respectively. Benidipine blocked calcium influx through the L-type voltage dependent calcium channel of MC3T3-E1 more potently than amlodipine or nifedipine. These calcium channel blockers did not change collagen accumulation. Benidipine significantly increased in vitro mineralization at a concentration of 1 nM and higher, while amlodipine did so at 1 μM and nifedipine did not. Comparison of the effective concentration of each calcium channel blocker in our study with the reported maximum serum concentration of each drug suggests that benidipine, but not amlodipine or nifedipine, promotes mineral deposition in human.

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過栄養は肥満、糖尿病、脂質異常症などの生活習慣病に直結し、その食事・栄養管理はそれらの疾患の根本的な治療法として認識され、その重要性に関しては論を待たない。高齢者においても過栄養状態は存在し、若年者、成人と同様に生活習慣病に関わり健康障害に関与していることは間違いない。しかし、一方で高齢者においては、特に後期高齢者においては、栄養障害のリスクを持ち合わせているという点で過栄養とは真逆の低栄養に関する注意も必要である。さらに高齢者における過栄養は若年成人ではあまり考慮に入れる必要のない、高齢者に特有な病態にも関与していることを強調したい。

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A 72-year-old man with a malignant retroperitoneal soft tissue tumor was treated with ifosfamide (IFO) for 5 consecutive days (1.8 g/m²/d×5 d, expected dose 9 g/m²). The patient developed neurological symptoms such as mild somnolence, seizures, and inability to write from Day 1, and became delirious on Day 3, so IFO was discontinued on Day 4 (dose: 7.2 g/m²). Since there are reports of drug interactions that increase the frequency of encephalopathy when combined with aprepitant (Apr), Dexamethasone was increased and IFO was administered without the use of Apr after the second course, and there was no recurrence of encephalopathy in the second and third courses. IFO-induced encephalopathy is considered to occur due to an increase in blood concentration of IFOs caused by high dosage, decreased renal function, or other factors. In this case, encephalopathy was observed even though the dose of IFO was reduced due to the patient’s advanced age and impaired renal function. The combination use of Apr with IFO should be considered with caution for the occurrence of adverse events, including encephalopathy, and if possible, control of gastrointestinal toxicity with other antiemetic agents should be considered.

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1α,25-dihydroxyvitamin D₃ [1,25-(OH)₂D₃] phosphorylates the extracellular signal-regulated kinase (ERK), a member of the mitogen-activated protein kinase (MAPK) family, within 30 sec in primary cultured chick skeletal muscle cells. MAPK of HeLa cell lines, which had been stably transfected with a cDNA library derived from mRNA of chick skeletal muscle cells, was also rapidly phosphorylated by 1,25-(OH)₂D₃. These cell lines have the potential to be a good tool for further investigation of rapid non-genomic mechanism activated by 1,25-(OH)₂D₃.

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We examined the effects of vitamin D₃ on extracellular signal-related kinase (ERK). 1,25-(OH)₂D₃, a form active in inducing transcription, caused rapid and transient ERK activation. 24R,25-(OH)₂D₃, an inactive form, also activated ERK. In contrast, (22R)-22-methyl-20-epi-1,25-(OH)₂D₃, a synthetic agonist of 1,25-(OH)₂D₃, was not effective. These data provide evidence of selective roles of vitamin D₃ in nongenomic and genomic actions.

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Immobilized enzyme reactors (IMERs) integrated into an LC-NMR system were developed for rapid and detailed structural identification of enzymatic reaction products. An on-column enzymatic reaction was achieved for immobilized cytochrome-c and dog microsomes. After the reaction, these products were analyzed by LC-NMR without any work-up processes. The immobilized cytochrome-c column integrated into LC-NMR was used to characterize the reaction product formed on N-demethylation by measurement of ¹H-NMR. In the case of reaction taking place on the microsome column, a glucuronidation product was identified by ¹H-NMR and ¹H–¹H correlated spectroscopy. The chemical structures of the enzymatic reaction products could be elucidated by IMER-LC-NMR without the need for authentic samples or isolation processes.

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Relations between the traction performance of a wheel tractor and the wheel slippage were studied. The slip ratio which gives maximum tractive power lies in a little lower value from the slip ratio which gives maximum tractive force.
Maximum traction slippage differs according to the traction speed, but it was observed that slippage is closely related to the slip speed. In these experiment, maximum traction was observed at the slip speed of 0.2m/s. In this case, maximum tractive power is expected at the driving speed of 0.5m/s, which is the rating speed of the first gear.
For the stability of the traction, operating point should not exceed the maximum traction slippage. Motion of the tractor in the unstable zone may be described by the Van del Pol equation. Solution of the equation using electronic analog computer gives fair agreement with the experimental results.

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Vitamin D deficiency has been reported to result in impaired glucose tolerance and decreased insulin secretion when glucose is administered either intravenously or in-traperitoneally. The aim of the present study was to study oral glucose tolerance and glucose absorption in a vitamin D-deficient rat model, Oral glucose tolerance tests were carried out in vitamin D-deficient and control rats, and this was found to be unaltered in the deficient state. Intestinal absorption of glucose was drastically reduced in the deficient animal and was found to be due to a reduction in the sodium-dependent component of glucose trans-port. Thus the unaltered oral glucose tolerance in the vitamin D-deficient rat is probably due to impaired absorption of glucose.

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