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Biomedical subjects

K Imai

Publications and source records attributed to K Imai.

At least 1,279 records · Page 71Linked to original sources
PubMed1986

[Bilateral renal cell carcinoma: report of a case].

A case of asynchronous bilateral renal cell carcinoma is reported. The patient was a 71-year-old man who visited our clinic with complaints of asymptomatic macrohematuria and fever on November 20, 1960. Clinical diagnosis was left renal tumor and left nephrectomy was performed on December 4, 1960. Histological diagnosis was renal cell carcinoma (common type, clear cell subtype, alveolar type and G1). The postoperative course was uneventful until complaints of diarrhea and weight loss in November, 1983. He visited our clinic again with a right abdominal mass on January, 1984. Right renal selective angiography revealed an enlargement and abnormal vascularity with tumor stain, hypervascularity and pooling in the whole kidney except for the upper pole lesion. CT scan revealed a space occupying lesion. Right radical nephrectomy was performed on March 6, 1984. Histological diagnosis was renal cell carcinoma (common type, mixed subtype, alveolar and tubular type, G2). He was treated by hemodialysis and steroid therapy after right nephrectomy but he died of massive gastro-intestinal bleeding on April 22, 1984. The paper is the 15th report of a bilateral renal cell carcinoma in Japan.

Aged↗
PubMed1986

[Serologic diagnosis of digestive tract cancer].

Serologic diagnosis using body fluids is easy to perform and the analysis of abnormal body fluids can play an important role in diagnosis for cancer. Monoclonal antibodies to tumor associated antigen have contributed very much to this important field, CA 19-9 being an excellent example. We have also established novel monoclonal antibody YH 206 which reacted with the antigen in the sera of approximately half of the patients with gastric or pancreatic cancer. Recent advances in diagnosis using gastric and pancreatic juice were also reviewed.

Adenocarcinoma↗
PubMed1985

Immunohistologic distribution of CEA defined by human anti-CEA antibody in the serum of a colonic cancer patient.

The serum from a colonic cancer patient was examined showing anti-CEA (carcinoembryonic antigen) activity but not anti-NCA (nonspecific cross-reacting antigen) activity. Conventional immunoelectrophoresis and radioimmunoelectrophoresis in conjunction with iodine 125-labeled CEA strongly suggested that this serum contained M-protein (IgG kappa). Most of the anti-CEA activity was found in the M-component using radioimmunoelectrophoresis, suggesting the monoclonal nature of anti-CEA autoantibodies. With the use of this serum the histologic distribution of the antigen by the immunoperoxidase method was demonstrated for the first time. Anti-CEA specificity of this serum was confirmed by the fact that the absorbed antibody with purified CEA gave negative staining of the serial sections of the tissues that formerly had immunostaining. Interestingly, this distribution was almost superimposed on that detected by the murine monoclonal anti-CEA antibody AS802. The data suggested that the antibody in the serum reacted with the CEA molecule in the tissue sections, the majority of which were found in the cancerous tissues.

Adenocarcinoma↗
PubMed1985

[Studies of progestin specific binding protein in the human prostate. [III]; Sodium molybdate effect on SDG analysis].

The effect of sodium molybdate on the specific binding protein (SBP) of synthetic progestin 17 alpha-methyl-[3H]-promegestone (R5020) in the cytosol of the human prostate was studied. In a sucrose density gradient analysis, two R5020 SBP components at 4S and 7-8S were observed. It was apparent that the 4S component was reduced and the 7-8S component increased with the addition of 10mM sodium molybdate into the cytosol. Therefore, the molybdate enhancement degree on total SBP amount (4S plus 7-8S) was decided by the relationship between the decreasing rate at 4S and the increasing one at 7-8S. It was shown that the molybdate effect was time-dependent and was not related to the SBP state, whether it was bounded with steroid or not. Moreover, it was estimated that the molybdate effect was not related to phosphatase inhibition since R5020 SBP in SDG was not enhanced by the addition of sodium fluoride which was a phosphatase inhibitor. In this report, the possibility of the existence of the 7-8S forming factor in the human prostate and the relationship between it and sodium molybdate was also discussed through an experiment on a Sephadex G-25.

Carrier Proteins↗
PubMed1985

Involvement of Glu G3(101)beta in the function of hemoglobin. Comparative O2 equilibrium studies of human mutant hemoglobins.

The glutamyl residue at G3(101)beta of normal hemoglobin (Hb A) is one of the alpha 1 beta 2 subunit contacts which are vital to O2 binding properties of the molecule. The O2 equilibrium properties of the four mutants with different substitutions at this site are studied in order to elucidate the role of this residue. Under stripped conditions with minimum chloride the order of O2 affinity is: Hb A (Glu) much less than Hb Rush (Gln) less than or equal to Hb British Columbia (Lys) less than or equal to Hb Potomac (Asp) less than or equal to Hb Alberta (Gly). The first Adair constants, K1, for the mutant hemoglobins are greater than that for Hb A whereas the fourth, K4, are similar, indicating that the allosteric constants (L) of these mutants are greatly reduced. Therefore, the G3(101)beta residue contributes intrinsically to the strengthening of the structural constraints that are imposed upon the deoxy (T) forms but not the oxy (R) form. On addition of 0.1 M Cl- and further addition of 2,3-diphosphoglycerate or inositol hexaphosphate, their O2 affinities and cooperativities are altered, reflecting different responses to anionic ligands. Hb Rush exhibits a stronger chloride effect than Hb A and the other variants and, as a result, an increased Bohr effect and a smaller heat of oxygenation at pH 6.5. These changes are consistent with an increased positive net charge in the central cavity of Hb Rush and subsequent extra anion binding in the deoxy form. The tetramer to dimer dissociation constants are estimated to be greater than normal for Hb British Columbia and less than normal for Hb Alberta. This comparative study of the G3(101)beta mutants indicates that the size and the charge of this residue may influence the switching of two neighboring interchain hydrogen bonds that occurs during oxygenation of normal hemoglobin.

Allosteric Site↗
PubMed1985

Sensitive high-performance liquid chromatography system with fluorometric detection of three urinary catecholamines in the same range.

A simple and highly sensitive HPLC method for the simultaneous determination of three catecholamines (norepinephrine, epinephrine, and dopamine) was developed. Catecholamines were separated on a reversed-phase column, reacted with ethylenediamine at 70 degrees C and pH 8.2 for 4 min, and fluorometrically determined. Those detection limits were in the same range of 20 to 40 pg. When the method was applied to human urine samples, 3,4-dihydroxyphenylalanine, their precursor, was also determined.

Catecholamines↗
PubMed1985

Oxygen-binding characteristics of Potamilla chlorocruorin.

Accurate oxygen equilibrium curves of chlorocruorin of a marine polychaete annelid, Potamilla leptochaeta, were determined under a variety of experimental conditions. Like chlorocruorins from other species Potamilla chlorocruorin exhibited a low oxygen affinity, a large Bohr effect, and high cooperativity compared to those of human hemoglobin. However, in contrast to chlorocruorins from other species, the shape of the oxygen equilibrium curve for Potamilla chlorocruorin varied dramatically upon changes of pH or temperature. As observed in hemocyanins and annelid hemoglobins, cations, especially divalent ones such as Mg2+ and Ca2+, caused marked increase in oxygen affinity and cooperativity of Potamilla chlorocruorin. This finding together with the determination of cations in Potamilla blood has made clear the physiological role of chlorocruorin as an oxygen carrier. A graphical analysis based on the Monod-Wyman-Changeux allosteric model indicated that the number of sites for oxygen binding involved in heme-heme interactions is six, defining the functional unit of chlorocruorin molecule.

Allosteric Regulation↗
PubMed1985

[Studies of progestin specific binding protein in the human prostate (II): The possibility of non-specific binding protein disturbance for the accurate quantitative assay of 4S specific binding protein].

The R5020 specific binding protein in the human prostate was studied to elucidate the cause for the poorer reproducibility of 4S high affinity complex sediment than that of 7-8S high affinity complex sediment. The sucrose density gradient, with a low ionic strength buffer including sodium molybdate, was used. Charcoal assay is one of the most common methods used in steroid receptor studies. However, there is a possibility that the high amount of non-specific binding protein common in the human prostate disturbs the charcoal function which removes the free and also the loosely bound steroids from low affinity protein. In the sucrose density gradient process, charcoal treatment is necessary to obtain the apparent 7-8S peak from the 4S one because 7-8S is covered with huge 4S when the charcoal treatment is not performed. 4S complex is proved to be more sensitive than 7-8S to this form of treatment in this study. In addition, the R5020 specific binding protein is found in not only 7-8S complex but also 4S. The dissociation constant of 4S protein is identified with that in 7-8S in the low range of [3H]-R5020(0.4-5.2 nM) using Scatchard plots, but not in the high range (1.3-10.4 nM). Thus, it seems possible that the high amount of non-specific binding protein disturbs the accurate quantification of specific binding protein in 4S. In conclusion, the poor reproducibility of 4S complex through charcoal treatment is caused by the presence of the high amount of non-specific binding protein in the human prostate.

Animals↗
PubMed1985

Distribution and organelle specificity of melanoma-associated antigens identified by Mo 465.12 in human malignant melanoma.

Mo 465.12 (Mo 465) is a unique monoclonal antibody that detects cytoplasmic antigens highly restricted to the cells of human malignant melanoma (MM). As yet, it is not known which cytoplasmic components are reactive with Mo 465 within MM cells. This study, using the enzyme-linked immunosorbent assay (ELISA) technique, examines the distribution and specificity of Mo 465-reactive proteins in MM tissues that were isolated by cell fractionation and solubilized by a nonionic detergent (Brij 35). Light microscopically, Mo 465 bound strongly to the cytoplasm of MM cells, being localized as patchy or microgranular, but not to the normal epidermal melanocytes. When the cultured MM cells were fractionated, Mo 465 reacted with both soluble and membrane fractions and with the spent culture medium. To further identify the organelle specificity of Mo 465-reactive proteins, metastatic human MM and normal human liver tissues were separated into the fractions of large granules, small granules, Golgi apparatus, mitochondria, rough endoplasmic reticulum (ER), smooth ER, microsomes, and melanosomes. Mo 465-reactive proteins were detected in the fractions of crude homogenate, microsomes, and rough ER of MM tissue, and their reactivities were in parallel to the concentration of solubilized protein. the findings indicate that Mo 465-reactive proteins are localized in rough ER, that they are released into the cytoplasm, and that in the in vitro condition they are shed into the culture medium.

Antibodies, Monoclonal↗
PubMed1985

Influences of metal ions on the reaction of amino and imino acids with fluorogenic reagents.

When a twofold excess of metal ions (Cu2+, Ni2+, Zn2+, Mg2+, Ca2+, Fe3+, and Al3+) was added to a reaction medium of amino acids (1-50 microM each) with the fluorogenic reagents NBD-F (4-fluoro-7-nitrobenzo-2-oxa-1,3-diazole), DNS-Cl (5-N,N-dimethylaminonaphthalenesulfonyl chloride), OPA (o-phthalaldehyde), and fluorescamine (4-phenylspiro[furan-2(3H),1'-phthalan]-3,3'-dione), a reduction of derivatization was observed. The effect was especially marked on the reaction with NBD-F. The derivatization of His and Asp with DNS-Cl and fluorescamine and of His with OPA was suppressed by Cu2+ and/or Ni2+. The suppression by the metal ions can be overcome by the addition of EDTA to the reaction medium. For determination of a small amount of amino and imino acids (less than microM) the addition of a chelating reagent to biological samples is recommended before derivatization with these electrophilic reagents.

4-Chloro-7-nitrobenzofurazan↗
PubMed1985

Application of a fluorogenic reagent, ammonium 7-fluorobenzo-2-oxa-1,3-diazole-4-sulfonate for detection of cystine-containing peptides.

A simple, sensitive and reliable method for the detection of cystine-containing peptides has been developed. A peptide bridged with a disulfide bond was reduced and cleaved with tributylphosphine, and then coupled with a thiol specific reagent, ammonium 7-fluorobenzo-2-oxa-1,3-diazole-4-sulfonate, under alkaline conditions. After incubation at 60 degrees C for 1 h, the fluorescent derivative formed was measured with excitation at 385 nm and emission at 515 nm. The intensity of fluorescence labeled to the peptide was very stable and the peptide containing disulfide was quantitatively determined in the range of 100 pmol to 10 nmol, when oxidized glutathione was used as a standard. This method was very useful for specific detection of cystine-containing peptides in the column effluents on reverse phase high performance liquid chromatography.

Chromatography, High Pressure Liquid↗
PubMed1985

Immunological analysis of glycolipids on cell surfaces of cultured human tumor cell lines: expression of lactoneotetraosylceramide on tumor cell surfaces.

Glycolipids of human cell lines of colonic adenocarcinoma (Colo 205 and BM 314), gastric tumor (AZ 521 and KATO-III), and lung tumor (A 549) were studied by the immunohistochemical fluorescence technique, flow cytometric analysis and immunostaining on thin layer chromatoplates with antibodies against gangliotriaosylceramide (Gg3Cer), gangliotetraosylceramide (Gg4Cer), fucogangliotetraosylceramide (Fuc-Gg4Cer), blood group B active lipid, globopentaosylceramide (Gb5Cer) and lactoneotetraosylceramide (nLc4Cer). Anti-nLc4Cer antibody was the only antibody which reacted with all the tumor cell lines used. The glycolipid fractions of each cell line separated by Iatrobeads column chromatography were immunostained with the six antibodies mentioned above on thin layer plates. The presence of nLc4Cer was detected in all cell lines. On the other hand, Gg4Cer was detected in gastric tumor cell lines, and Gg3Cer was detected in AZ 521. Based on these results, the tumor cell lines were analyzed by flow cytometry using anti-nLc4Cer antibody. About 70% of total cells in each cell line were separated as nLc4Cer-expressing cells. The present findings, together with the occurrence of nLc4Cer in ascitic fluids of cancer patients (Taki, T., Kojima, S., Seto, H., Yamada, H., & Matsumoto, M. (1984) J. Biochem. 96, 1257-1265), suggest that nLc4Cer may be a tumor-associated lipid.

Adenocarcinoma↗
PubMed1985

Characterization of beta-glucosidase as a peripheral enzyme of lysosomal membranes from mouse liver and purification.

Lysosomal membrane fractions were prepared from lysosomes of mouse liver by freeze-thawing in a hypotonic buffer: 54% of beta-glucosidase [EC 3.2.1.45] in lysosomes was associated with the membrane fractions, whereas 96% of beta-glucuronidase [EC 3.2.1.31] was recovered in the soluble fractions of lysosomes. beta-glucosidase was solubilized by pH 9.5 treatment or by Triton treatment of membranes. The enzyme solubilized with alkali and concentrated with (NH4)2SO4 was rapidly inactivated in a solution of pH 9.5, but could be protected against inactivation by acidic detergent. Gel filtration analysis indicated that beta-glucosidase was in an aggregated form at neutral pH and could be disaggregated by alkali and detergents. The enzyme dissociated with detergents also showed a higher activity than the alkali-treated enzyme. These results suggested that beta-glucosidase is a peripheral enzyme bound to acidic lipids in membranes. beta-Glucosidase was purified to apparent homogeneity by (NH4)2SO4 fractionation and chromatographies with Sephacryl S-300, hydroxylapatite and cation exchangers in the presence of detergents. The catalytic activity of the purified enzyme was maximally stimulated by phosphatidylserine and heat-stable protein in the presence of a low concentration of Triton X-100. The stimulation was mainly due to an increase in Vmax.

Animals↗