Benzyl-14C-1- [bis (4-fluorophenyl) methyl] -4- (2, 3, 4-trimethoxybenzyl) piperazine dihydrochloride (14C-KB-2796), a new cerebral vasodilator, was synthesized in order to investigate the metabolic fate. The synthesis of carboxy-14C-2, 3, 4-trimethoxybenzoic acid (IV) was accomplished by the reaction of 2, 3, 4-trimethoxybromobenzene (II) with tert-butyllithium followed by carboxylation with14C-carbon dioxide generated from14C-barium carbonate. Formyl-14C-2, 3, 4-trimethoxybenzaldehyde (VI) was prepared by the reduction of the methyl ester of IV. The free base of14C-KB-2796 was obtained by the condensation of VI with bis (4-fluorophenyl) methylpiperazine, and converted to I. An overall radiochemical yield from14C-barium carbonate was 39%, the specific activity was 1816.7MBq/mmol (49.1mCi/mmol) and its radiochmical purity was 99% in reverse isotope dilution analysis and thin layer chromatographic method.
We studied the tumor-localizing characteristics of alicyclic a-amino acid analogs (a-j) without α-hydrogen, because of the selective affinity of synthetic nonmetabolizing amino acids such as 1-aminocyclopentanecarboxylic acid (ACPC) and α-aminoisobutyric acid (α-AIB) to tumor tissues. Ten different alicyclic α-amino acids (a-j) were labeled with 14C using a modified Bucherer synthesis for amino acids. The tissue distributions and whole-body autoradiographic study of these 14C-labeled alicyclic α-amino acid analogs (a-j) were investigated in mice bearing Ehrlich tumor. These results showed that the tumor uptakes and tumor to tissue concentration ratios increased with decreasing ringsize in homologous series (8- through 4-membered ring systems) and alicyclic α-amino acid analogs containing 3- or 4-methyl group had the higher tumor to tissue concentration ratios. On the other hand, alicyclic α-amino acid analogs containing 2-methyl group and 4-phenyl group showed the lower tumor uptakes and the lower tumor to tissue concentration ratios. These results suggest that the small ringsize alicyclic α-amino acid analogs containing 3-methyl group such as 3-methyl-l-aminocyclopentanecarboxylic acid (3-McACPC) may be effective for the early detection of tumors.
Regional cerebral blood flow (rCBF) was measured in 20 patients with ruptured aneurysm. rCBF images are obtained by 133Xe inhalation method using a ring type gamma camera (SET-020, Shimadzu Co.) with high sensitivity collimator. Examinations are performed at acute stage (1-7 days after onset) and at subacute stage (8-14 days after onset) . In acute stage, rCBF in the affected cerebral hemisphere has tendency to be low in 12 patients with angiospasm after the aneurysmal rupture comparing to those in patients without angiospasm. Low rCBF areas in cerebral hemisphere at acute stage were apt to become normal in subacute stage. rCBF measurement by 133Xe inhalation method seemed to be an useful method to evaluate rCBF in patients with ruptured aneurysm.
Ambient dose equivalent rate constant (which is the quotient of l2H* (10) by A, where H* (10) is ambient dose equivalent rate at 10 mm depth due to photons at a distance l from a point source of the nuclide having an activity A) is calculated for 50 nuclides. The limitation of the validity of the quantity is also discussed.
The amino sequence recognizable parathyroid hormones (PTH) in lower and non-lower magnesemic groups in randamized samples were measured by using various kinds of the well established PTH kits. The levels of carboxy terminal, mid-region and intact PTH in lower magnesemic group were more decreased than these in non-lower magnesemic group. It is likely that the shortage of magnesium in serum makes a suppression of PTH secretion.
The clinical significance of osteocalcin in sera of bone tumors were measured in sera of various kinds of bone tumors. The levels of osteocalcin were higher in bone tumors than those in normal subjects. Serum osteocalcin levels in hypercalcemic groups of bone metastasis and myeloma showed a remarkable increase in a parallelism with serum ALPand LDH levels. These results suggested to be directly or indirectly activated on osteoblast by bone tumors and to be synthesized osteocalcin in osteoblast.