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Biomedical subjects

G Kosaki

Publications and source records attributed to G Kosaki.

At least 109 records · Page 6Linked to original sources

[Pancreatic cancer-related antigen (PCAA) and pancreatic tissue antigen (PaA)--their chemical compositions, tissue localization, and clinical significance].

PCAA, a glycoprotein antigen identified and purified from ascited fluid of a pancreatic cancer patient and sharing the identical immunogenicity with Gelder's POA (Shimano, 1981) and PaA, a novel pancreas tissue antigen (Loor, 1981) purified from saline extract of human pancreas were studied. (1) Chemical composition: The purified PCAA from ascites fluid of a pancreatic cancer patient has a molecular weight of 10,000,000. The same antigenic substance as PCAA was also isolated and purified from normal colonic mucosa. Amino acid compositions of these antigens were similar. PCAA appeared to be a N-glycosidic glycoprotein. Antisera against these antigens were immunologically identical to Gelder's anti-POA in gel diffusion. The purified PaA has a molecular weight of 44,000, a sedimentation coefficient of 3.4S and an isoelectric point of 4.9. (2) Tissue localization: In pancreatic cancer tissues, PCAA and PaA were detected at apical cytoplasm of cancer cells, though positive cells were in different proportions and with different distribution each other. PCAA-positive cells were well differentiated while PaA-positive cells were less differentiated in histology. (3) Serum levels: A sensitive and reproducible sandwich-type enzyme immunosorbent assay has been developed for quantitation of PCAA and PaA. Using 18.6 micrograms/ml (mean + 2 S.D. of normal controls) as an upper limit, 43 of 76 pancreatic cancer (56%) and 34 of 167 other diseases (20%) had an elevated PCAA level. Using 21.5 ng/ml as an upper limit, 50 of 76 pancreatic cancer (66%) and 13 of 167 other diseases (8%) had an elevated PaA level. The sensitivity of simultaneous assay of PCAA and PaA for the detection of pancreatic cancer increased to be 90% (69/76) while false positive was 24% (40/167). The results indicate that combination assay of PCAA and PaA may be useful in immunodiagnosis of pancreatic cancer.

Antigens, Neoplasm↗

[Urinary epinephrine and norepinephrine excretion in patients with medullary thyroid carcinoma and their relatives].

Medullary thyroid carcinoma can arise as a component of multiple endocrine neoplasia (MEN) syndrome which includes adrenal pheochromocytoma. Familial medullary thyroid carcinoma with no association of other components of MEN syndrome is also reported. Epinephrine and norepinephrine excreted in 24 hour urine and/or randomly voided urine were measured for screening of pheochromocytoma in patients with medullary thyroid carcinoma of either the hereditary or sporadic type and in their relatives. Six patients with clinical symptoms and signs suggesting pheochromocytoma had a markedly increased epinephrine and epinephrine/norepinephrine (E/N) ratio and a less dominant increase of norepinephrine in 24 hour urine. The diagnosis of pheochromocytoma was proved later at surgery. Among 10 patients with hereditary medullary thyroid carcinoma without any clinical symptoms and signs for pheochromocytoma, 6 patients had increased epinephrine and E/N ratio and normal norepinephrine, and the remaining 4 had normal epinephrine, norepinephrine and E/N ratio in 24 hour urine. The six patients with increased epinephrine and E/N ratios were regarded as having latent adrenal medullary hyperfunction. The mean ages of the 6 patients with proved pheochromocytoma, the 6 with latent adrenal medullary hyperfunction and the 4 with normal urinary catecholamine fractions were 51.3, 42.5 and 28.5 years, respectively. At least one patient in each family with hereditary medullary thyroid carcinoma had proved pheochromocytoma or latent adrenal medullary hyperfunction, leaving no family with hereditary medullary thyroid carcinoma only. Urinary epinephrine, norepinephrine and E/N ratios in patients with sporadic medullary thyroid carcinoma and relatives of patients with medullary thyroid carcinoma were not higher than those in normal subjects. Measurements of epinephrine and norepinephrine in randomly voided urine are also a valuable and convenient method for the screening of pheochromocytoma in patients with medullary thyroid carcinoma and their relatives, because they gave results similar to those in 24 hour urine.

Adolescent↗

Cleavage of cytoskeletal proteins by two forms of Ca2+ activated neutral proteases in human platelets.

Two forms of calcium activated neutral proteases (CANPs) with different affinity to Ca2+ were partially purified from the soluble fraction of human platelets; one (mu-CANP*) required 6 muM Ca2+ and the other (m-CANP*) did 900 muM Ca2+ for the respective half maximal activity. Human platelets were found to contain mu-CANP predominantly in contrast to our previous study in bovine platelets, in which mu- and m-CANP were equally distributed. Among platelet protein preparations examined for possible endogenous substrates of platelet CANPs, actin binding protein (ABP) and 230 K protein were proteolysed completely by mu- or m-CANP in the presence of the respective optimal concentration of Ca2+. As far as mu-CANP is concerned, this is the first demonstration of proteolysis of endogenous substrates, which implies possible involvement of mu-CANP in stimulus-linked platelet reaction coupled with an increase in intracellular Ca2+ to micromolar concentration. Furthermore, microtubules associated proteins (MAPs) of bovine brain was proteolysed by mu- or m-CANP of human platelet in the similar manner, indicating functional ubiquity of CANPS.

Blood Platelets↗

A simple and rapid method to detect platelet associated IgG.

In order to measure platelet associated IgG (PAIgG), a semiquantitative method was devised, utilizing the ability of staphylococcal protein A (SpA) to bind human IgG specifically. Platelets bound to sheep red blood cells coated with SpA were separated from non-bound platelets by centrifugation through Ficol-paque solution and an adhesive percentage (Binding Rate) was calculated by enumeration of platelets remaining in an upper phase. In a total of 72 cases including 15 cases of idiopathic thrombocytopenic purpura (ITP), PAIgG was studied, using this new method and quantitative Fab, anti-Fab assay. Binding Rate was 9.3 +/- 3.8% in normal subjects and 26.5 +/- 10% in ITP patients, which difference was statistically significant (p less than 0.01). A good correlation was observed between Binding Rate and peripheral platelet count in ITP (r = 0.7299, p less than 0.01) and also between Binding Rate and values of PAIgG by Fab, anti-Fab assay (r = 0.8309, p less than 0.01). These results indicate that this new method is reliable to detect PAIgG in addition to its simplicity and rapidity.

Blood Platelets↗

Purification, characterization and development of radioimmunoassay of human liver ribonuclease.

Human liver ribonuclease (RNase) was purified 36000-fold into an electrophoretically homogeneous state by column chromatography on phosphocellulose, gel filtration, poly(G) affinity chromatography, and heparin affinity chromatography. The molecular weight of the RNase estimated by SDS disc electrophoresis was 19,500. RNase was a heat- and pH-stable protein, and optimum activity was obtained at pH 7.0. The radioimmunoassay (RIA) for human liver RNase has been developed and the assay was shown to be sensitive (20 ng/ml), reproducible and specific. A good parallel relationship was observed between the standard curve and the dilution curves for serum and urine. No cross-activity was demonstrated between human liver and pancreatic RNase (less than 1%). In 44 normal subjects, the mean serum concentration of liver RNase determined by the RIA was found to be 99.4 ng/ml (SD +/- 66.3).

Adult↗

Effects of chronic renal failure on wound healing in rats. I. Biomechanical study.

Chronic renal failure was induced in rats by a five-sixths nephrectomy, after which incisional wounds were made in the abdominal skin, aponeurosis of linea alba, stomach and colon. Bursting strength of the colon and tensile strength of the skin, aponeurosis and stomach were usually lower in the uremics than in the controls, but there was no statistical significance except for colonic wounds on the 7th and 10th postoperative days. Before these results can be extrapolated to clinical cases, pre- and post-surgical treatment must be considered, because immunosuppressants, anticoagulants, and other compounds may influence the retardation of wound healing.

Animals↗

Effects of chronic renal failure on wound healing in rats. II. Microscopic study and hydroxyproline assay.

Incisional wounds of the abdominal skin, aponeurosis, stomach and colon were investigated microscopically for a comparison of the findings between uremic and normal rats. The grade of edema and number of inflammatory cells were increased in the rats with uremia and the granulation zone was also larger in the uremics. Hydroxyproline was assayed in the wound tissues by a modification of the technique of Stegemann and Stalder. The hydroxyproline level was lower in the uremics (p less than 0.05) only in the aponeurosis of the 5th postoperative day and in the colon of the 3.5th to 7th day. The correlation coefficient calculated for the blood urea level, biomechanical strength and hydroxyproline level was nil. If these results can validly be extrapolated to patients with chronic renal failure, careful management and avoidance of possible wound infections is of the greatest importance for surgical patients.

Animals↗

Purification and characterization of phosphatidylinositol-specific phospholipase C from bovine platelets.

Phosphatidylinositol-specific phospholipase C was purified to homogeneity from soluble fraction of bovine platelets by ammonium sulfate fractionation, hydrophobic chromatography, DEAE ion exchange chromatography and gel filtration. The purified enzyme has a narrow pH optimum ranging from 6.5 to 7.5 and the molecular weight of the enzyme was estimated to be 143,000 by sodium dodecyl sulfate slab gel electrophoresis. The purified enzyme requires Ca2+ strictly for activity, which was markedly enhanced in the presence of arachidonate. No enhancement of the activity was observed in the presence of purified calmodulin. The activity was markedly inhibited in the presence of quinacrine but no inhibition by indomethacin was observed.

Animals↗

Passive enhancement of rat heart allografts by xenogeneic antidonor sera raised in rabbits.

Antilymphocyte serum (ALS) was raised in rabbits immunized by administration of lymphoid cells from Sprague-Dawley (SpD) rats. The ALS was rendered specific for the SpD strain by complete absorption by Wistar rat lymphoid cells. The specificity was considered to be predominantly directed to SpD Ir gene-associated (Ia) antigens, since absorption by SpD erythrocytes failed to abolish lymphocytotoxic activities. Alloantibody production by Wistar rats sensitized with SpD spleen cells was completely inhibited by simultaneous injections of SpD-specific ALS. This effect was specific as normal alloantibody production occurred when Wistar rats were immunized with ACI cells, as a third party. Although this ALS exhibited restricted enhancing ability on skin allograft survival, it was capable of significantly prolonging the survival of heart allografts from SpD to Wistar rats. The ALS showed blocking activities on mixed lymphocyte culture (MLC) but had no effect on cell-mediated cytotoxicity (CMC). The enhancing activity was thus considered to be mediated by an afferent blockage of immune responses.

Absorption↗

Purification and characterization of gamma-glutamyl transpeptidase from human pancreas.

Gamma-glutamyl transpeptidase was purified from human pancreas to an electrophoretically homogeneous state. The enzyme was separated into two active fractions on a DEAE-cellulose column. Both enzyme preparations had the same molecular weight (9 x 10(4)) and were composed of two nonidentical subunits (molecular weight, 61,000 and 27,000). While the optimum pH and pH- and thermal-stability range of both enzymes were identical, their isoelectric points were considerably different. Following incubation with neuraminidase, however, the isoelectric point of F-11 became similar to that of F-I, suggesting that this difference in electrophoretic mobility is due to a difference in the content of sialic acid moiety.

Chromatography, Affinity↗

Immunochemical differences among carcinoembryonic antigen in tumor tissues and related antigens in meconium and adult feces.

We have isolated carcinoembryonic antigen (CEA)-related antigens from meconium and compared them with those in adult feces. Two CEA-related antigens were detected in meconium [nonspecific cross-reacting antigen 2 (NCA-2) and meconium nonspecific cross-reacting antigen] while four CEA-related antigens were found in adult feces [normal fecal antigen 1, normal fecal antigen 2 (NFA-2), normal fecal cross-reacting antigen, and fecal nonspecific cross-reacting antigen, respectively]. By conventional anti-CEA antisera, NCA-2 in meconium, NFA-2 in adult feces, and CEA in tumor tissues were indistinguishable from each other, but they could be distinguished by specific antibody preparations against a determinant unique to CEA (CEA-distinctive determinant) or to NFA-2 (NFA-2-distinctive determinant). Neither the CEA-distinctive determinant nor the NFA-2-distinctive determinant was detected on the NCA-2 molecule. No antigenic determinants unique to NCA-2 have been detected with the anti-NCA-2 antisera which we have prepared thus far. The molecular weight of purified NCA-2 was estimated to be 150,000 to 170,000 as compared to 160,000 to 170,000 for NFA-2 and 170,000 to 180,000 for CEA. NCA-2 had amino acid and carbohydrate compositions similar to those of CEA and NFA-2. All NFA-2 preparations and about one-half of the CEA preparations were sensitive to Pronase E digestion, which released two antigen fragments from these molecules, but NCA-2-preparations were resistant to such digestion.

Amino Acids↗

Changes in serum immunoreactive pancreatic elastase 1 in acute pancreatitis.

Serum immunoreactive elastase 1 content was significantly elevated in acute pancreatitis. The mean content of the control group was 1.79 ng/ml (SD: 0.62 ng/ml), while that of patients with acute pancreatitis was 23.02 ng/ml (SD: 9.44 ng/ml). The increased content of pancreatic elastase 1 in acute pancreatitis continued for several days after onset, even though serum amylase activity had returned to normal.

Acute Disease↗

Purification and immunological characterization of human pancreatic ribonuclease.

Three alkaline RNases were purified from human pancreatic juice to near homogeneity as judged by sodium dodecyl sulfate and native polyacrylamide gel electrophoreses. The molecular weights of these RNases determined by sodium dodecyl sulfate electrophoresis were 27,000, 19,000, and 13,000. The activities of these three RNases were increased by addition of Mg2+, Ca2+, Co2+, K+, Na+, spermine, and spermidine and decreased by the addition of heparin, Cu2+, and Zn2+. These RNases showed higher hydrolytic activity toward polycytidylic acid than toward polyguanylic acid, polyuridylic acid, or polyadenylic acid. The three human pancreatic RNases were immunologically identical but differed from human liver RNase, as shown by Ouchterlony double-diffusion test. Radioimmunoassay of human pancreatic RNase showed that immunologically similar RNases are present in human saliva, and serum.

Animals↗

[Effect of levamisole in postoperative adjuvant immunochemotherapy of stomach cancer--randomized controlled study of MMC-5-FU combination therapy with or without levamisole. 1].

A randomized controlled study by envelope method was carried out with the purpose of evaluating effects and side effects of levamisole in patients with resectable stomach cancer. The patients were randomly allocated to the treatment either with control or levamisole according to the indication of the envelope opened at least 3 days prior to surgery. The control group was treated with Mitomycin C (day 0, 20 mg day 1, 10 mg, one shot i.v.) and 5-FU(150 mg/day, p.o.). The levamisole group was treated with Mitomycin C, 5-FU and levamisole. Levamisole was administered at a daily dose of 150 mg for 3 consecutive days before surgery, and the 3 consecutive days administration schedule was repeated every fortnight for one year after surgery. Four hundred and forty-six patients were entered in this trial. However, with the exclusion of 104 patients as exceptions and dropouts, the total eligible patients were 342, consisting of 167 in the control group and 175 in the levamisole group. The effects were evaluated by comparing the disease-free interval or the survival time of both groups. There was no significant difference in the disease-free interval and survival. In this study, we have not yet reached the conclusion that levamisole is effective in prolonging disease-free interval and survival time, because high survival rates are still maintained in both groups for 2 years after surgery. The final conclusion would be drawn with the follow-up results in the future.

Adjuvants, Immunologic↗