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J Takada

Publications and source records attributed to J Takada.

89 records · Page 5Linked to original sources
PubMed1990

[Preparation of monoclonal antibodies against human bone gamma-carboxyglutamic acid containing protein (BGP) and its immunohistochemical application to various human tissues].

Bone gamma-carboxyglutamic acid containing protein (BGP) has been considered to play an important role in mineralization of bone, because this protein is capable of binding to calcium ions. However, the function and localization of BGP in normal bones have not yet been fully understood. In this study, we prepared monoclonal antibodies against human BGP, by immunizing BALB/c mice with human BGP. All five monoclonal antibodies obtained were shown to bind specifically to human BGP, but not to the other bone-derived proteins. In immunohistochemical analysis, these antibodies were shown to react with osteoblasts and osteocytes in normal human bone tissues, but not with chondrocytes, osteoclasts and osteoid tissues. These antibodies are expected to be useful for the diagnosis of human osteoblastic tumors and also for the analysis of the role of BGP in the ossification process in bone.

1-Carboxyglutamic Acid↗
PubMed1987

Occurrence of vanadium ion in serum albumins.

Vanadium was shown to be a contaminant in Sigma-grade serum albumins, fraction V. The levels of vanadium detected by neutron activation analysis were: bovine 16.7, ovine 10.0, rabbit 9.1, porcine 3.9, and human 0.19 micrograms/g protein. According to the ESR spectra, the vanadate form (+5 oxidation state) was strongly suggested as a chemical form present in albumins. Dialysis against a chelating agent was quite effective for removal of the metal ion.

Animals↗
PubMed1985

Partition of divalent and total manganese in organs and subcellular organelles of MnCl2-treated rats studied by ESR and neutron activation analysis.

The possibility that Mn2+ is converted to other valency states in vivo was examined by measuring the ratio of Mn2+, determined by ESR, to total manganese, determined by neutron activation analysis combined with chemical separation, in various organs of control rats and rats treated with MnCl2. In control rats, the total manganese content was high in the thyroid, hypophysis, adrenal, pancreas, liver and kidney, but the Mn2+ contents of these organs were low. In rats treated with Mn2+, the total manganese contents of all organs increased, but the Mn2+ contents still remained low. With regard to subcellular distribution, the total manganese content was high in the nuclear and mitochondrial fractions of the liver and kidney, and in the microsomal and supernatant fractions of the pancreas. The ratio of Mn2+ to total manganese was relatively high in the microsomes of the liver and kidney of control rats, and in the nuclear fraction of the pancreas of Mn2+-treated rats. Thus, the distribution and behavior of manganese in the pancreas were different from those in other organs. Purified liver nuclei and mitochondria were demonstrated to contain manganese, indicating that manganese is tightly bound in each cellular compartment.

Animals↗
PubMedDate not supplied

Pure red cell aplasia associated with parvovirus B19 infection in T-large granular lymphocyte leukemia.

There have been few reports of large granular lymphocyte (LGL) leukemia with neutropenia complicated with pure red cell aplasia (PRCA) that developed after human parvovirus (HPV) B19 infection. We report here the case of a 35-year-old female who developed HPV B19-associated PRCA with T-LGL leukemia. LGL count of peripheral blood was lower than 2 x 10(9) l(-1), although phenotypic analysis of LGL showed CD3+, CD16-, CD56-, CD57+ with double positive for CD3 and CD57, and genetic study showed the clonal rearrangement of T-cell receptor gene. Microscopically, the patient's bone marrow showed characteristic giant proerythroblasts. A serologic study of HPV B19 was positive for IgM, but negative for IgG, with a positive result on Dot-blot hybridization assay for HPV B19 DNA. Severe anemia and reticulocytopenia ameliorated without treatment 10 days after the initial examination, but slight anemia, neutropenia, a moderate increase of LGL counts with rearrangement of TCR gene, and positive result of HPV B19 DNA has persisted 7 months after the initial examination. We suggest that this viral infection may play an etiologic role in some patients with LGL leukemia who develop PRCA.

Adult↗
PubMedDate not supplied

A newly synthesized pyridine derivative, (Z)-5-methyl-2-[2-(1-naphthyl)ethenyl]-4-piperidinopyridine hydrochloride (AU-1421), as a reversible gastric proton pump inhibitor.

A newly synthesized pyridine derivative, (Z)-5-methyl-2-[2-(1-naphthyl)ethenyl]-4-piperidinopyridine hydrochloride (AU-1421), was found to inhibit the gastric proton pump in vitro and in vivo. In the leaky membrane vesicles of hog gastric mucosa, AU-1421 inhibited the K(+)-stimulated H, K-ATPase activity competitively with respect to K+, with a Ki value of 0.18 microM at pH 7.4 and 0.10 microM at pH 6.4. This inhibition was not affected by the length of the preincubation time of the enzyme with AU-1421, and activity was restored by dialysis. In the intact hog gastric membrane vesicles, which developed a pH gradient in the presence of valinomycin, AU-1421 also inhibited the gastric proton pump activity as measured by the quench of acridine orange fluorescence. In the isolated rabbit gastric glands, AU-1421 inhibited the histamine-, dibutyryl cAMP- and K(+)-stimulated uptake of [14C]aminopyrine into gastric glands with similar IC50 values of about 1 microM. Furthermore, AU-1421 suppressed gastric acid secretion in acute fistula rats and Heidenhain-pouch dogs with the same potency as cimetidine. These results suggest that AU-1421 is an antisecretory agent which reversibly inhibits the H,K-ATPase.

Adenosine Triphosphatases↗