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Biomedical subjects

W Sakamoto

Publications and source records attributed to W Sakamoto.

At least 127 records · Page 7Linked to original sources

Characterization of human salivary kallikrein: reactivities to human plasma kininogens and proteinase inhibitors.

In order to clarify the enzymatic properties of human salivary kallikrein, we investigated its actions on human plasma kininogens and response to proteinase inhibitors. Salivary kallikrein released kinin from both LMW and HMW kininogens, but acted preferentially on LMW kininogen. Salivary kallikrein did not completely release the kinin from HMW kininogen even after prolonged incubation (up to 60 min). The kinin releasing activity of salivary kallikrein was not inhibited by plasma proteinase inhibitors such as alpha 2M, alpha 2PI, AT III, and C1 INA after preincubation for 60 min at 37 degrees C, but was inhibited progressively by alpha 1AT as a function of preincubation time. SDS-PAGE revealed that concomitantly with the progressive inhibition a new band of 92,000 daltons, which seemed to be a complex of salivary kallikrein and alpha 1AT, was produced. The kininogen-depleted plasma inhibited the salivary kallikrein to the same degree as alpha 1AT. Therefore, it is suggested that alpha 1AT is the only inhibitor of salivary kallikrein in human plasma.

Humans↗

[Histopathological studies on bladder carcinoma. 2: Role of local lymph follicle and immunoblast cells].

The relationship between the cellular stromal reaction and systemic immunity was examined in 34 cases of bladder tumors. To determine the cellular stromal reaction, we examined the local lymph follicles such as peritumoral lymphocyte accumulation, and the immunoblast cells having abundant, basophilic cytoplasm with large vesicular nuclei which contained 1-3 large and irregular nucleoli. To measure systemic immunity, lymphocytes, T cells, B cells, IgG-Fc receptor T cells, and lymphocyte blast formation ratio with PHA were examined. The survival rate was higher in the group with a strong stromal reaction. The distribution of the immunoblast cells showed a tendency to accumulate in the paracortical area of the local lymph follicles. Examination of the depth of tumor infiltration and grade revealed many local lymph follicles and immunoblast cells in pT 2 and G 2 groups. The groups in which lymph follicles and/or immunoblast cells were positive showed a tendency of high lymphocyte blastformation ratio with PHA accompanied by a low percentage of IgG-Fc receptor T cells. These findings suggest that local lymph follicles and immunoblast cells may be a manifestation of the systemic immunity acting as a tumor defense mechanism.

Humans↗

[A case of spontaneous pyeloduodenal fistula].

A 71-year-old man was admitted for right loin pain and fever. DIP showed a non-visualizing right kidney. Retro- and antigrade pyelography demonstrated right hydronephrosis secondary to uretero-pelvic junction obstruction with leakage of the dye from the right kidney into the duodenum. Diagnosis of spontaneous pyeloduodenal fistula was confirmed at the operation. Right pyeloplasty was performed after closure of the duodenum. We believe that this is the 9th case reported in the Japanese literature.

Aged↗

[Diagnosis of bladder cancer by transurethral ultrasonic scanning].

Transurethral ultrasonographic examination was performed on a total of 24 patients with 40 bladder tumors to evaluate the accuracy of the method to detect bladder tumors and to compare ultrasonographic staging of bladder tumors with pathological staging. The results showed that it was difficult to detect bladder tumors of any size located in the bladder neck or dome and those less than 0.5 cm in diameter located anywhere, indicating the difficulty in tumor staging. On the other hand, diagnostic accuracy was approximately 90% for the tumors larger than 0.5 cm in diameter. Therefore, if a tumor with a diameter larger than 0.5 cm is detected by cystoscopy, we believe that urethral ultrasonographic examination should be performed as a routine protocol after the cystoscopy.

Aged↗

Studies on human high molecular weight (HMW) kininogen. III. Cleavage of HMW kininogen by the action of human salivary kallikrein.

Human high molecular weight (HMW) kininogen is a single chain with a molecular weight of 120,000 and is cleaved by plasma kallikrein sequentially into a nicked kininogen, an intermediate kinin-free protein (KFP-I), and a stable KFP-II. Here we report a study into the process of cleavage of human HMW kininogen by human salivary kallikrein. On incubation with salivary kallikrein, HMW kininogen was first converted into a nicked kininogen composed of disulfide-linked chains of 62,000 and 56,000 daltons. Subsequently, the nicked kininogen was cleaved into kinin and a KFP, which was apparently of equal size to the nicked kininogen, that is, KFP-I. In contrast to plasma kallikrein, salivary kallikrein did not cleave KFP-I into KFP-II. The two chains were separated by SP-Sephadex C-50 chromatography of reduced and alkylated KFP-I. The N-termini of HMW kininogen and the 62,000-daltons chain were found to be pyroglutamyl-isoleucyl, while that of the 56,000-daltons chain was found to be serine. These results indicate that the sequence of the two chains and kinin in human HMW kininogen is 62,000-daltons chain-kinin-56,000-daltons chain from the N-terminal end of HMW kininogen. Possible processes of cleavage of human HMW kininogen by human plasma and salivary kallikreins are also discussed.

Humans↗

Kininogen and kallikrein in saliva of periodontally-diseased subjects.

The kininogen level in saliva was measured by radioimmunoassay, and the kallikrein activity was determined by an enzymatic method with D-Val-Leu-Arg-p-nitroanilide. The kininogen level in the Periodontally-diseased Group was remarkably high compared with that of the Periodontally-healthy Group, but the kallikrein activity was approximately the same in the two groups.

Adult↗

Alpha 1-antitrypsin and alpha 2-macroglobulin do not inhibit the kinin-releasing activity of kallikreins from human urine and saliva.

Alpha 1-Antitrypsin, alpha 2-macroglobulin and low-molecular weight kininogen were isolated from human serum and kallikreins from human urine and saliva. Alpha 1-antitrypsin and alpha 2-macroglobulin inhibited the activity of trypsin in releasing kinin from low-molecular weight kininogen, due to their binding with the enzyme, but did not inhibit or bind with urinary and salivary kallikreins.

Humans↗

Purification and immunochemical properties of human low molecular weight kininogen.

A low molecular weight (LMW) kininogen was isolated from pooled human serum by chromatography on DEAE-Sephadex A-50, CM-Sephadex C-50, Sephadex G-150, and Sephadex G-100. It was shown to be homogeneous by ultracentrifugation, polyacrylamide gel electrophoresis, and immunoelectrophoresis. The sedimentation coefficient, S020,W, of purified LMW kininogen was 3.85 s, and its molecular weight was determined to be 78,000 by Sephadex G-100 gel-filtration. The LMW kininogen contained 79.3% protein, 8.0% hexose, 3.9% hexosamine, and 4.9% sialic acid. In order to determine the immunochemical properties of LMW kininogen, specific antiserum was prepared in rabbits. The antigenic determinant of LMW kininogen was not related to the sialic acid and kinin moieties in the kininogen molecule, but could not be distinguished from that of high molecular weight (HMW) kininogen. In the quantitative single radial immunodiffusion test, a sialic acid-free LMW kininogen reacted to a greater extent with the antiserum than the native LMW kininogen. The kininogen level in human serum was estimated by single radial immunodiffusion. The antiserum cross-reacted with monkey serum, but not with sera from dogs, rats, and mice, horses, pigs, guinea pigs, oxen, and rabbits.

Chromatography, Affinity↗

Immunochemical study of beta-glucuronidase inhibitor from porcine sublingual gland. Relationship between the antigenic determinant and the active site of the inhibitor.

Following removal of sialic acid by neuraminidase treatment the activity of the beta-glucuronidase inhibitor was remarkably decreased, but the antigenic determinant was not affected. A partial common antigen to the inhibitor was isolated from porcine small intestine, by successive fractionation of trypsin extraction of the latter on Sephadex G-150, DEAE-cellulose and Sepharose 4B column chromatography. The immunologic and characteristic properties of the common antigen were compared with those of the beta-glucuronidase inhibitor is not identical with its antigenic determinant.

Animals↗

Immunochemical study of beta-glucuronidase inhibitor from porcine sublingual gland. Interaction of beta-glucuronidase inhibitor with alpha2-macroglobulin.

Antiserum to the inhibitor of beta=glucuronidase isolated from porcine sublingual gland was prepared in rabbits. Double immunodiffusion with the inhibitor produced a single precipitin line. However, neutralization of the inhibitor was produced by the antiserum and also by normal serum. Anti-beta-glucuronidase inhibitor isolated from human serum, by fractionation with (NH4)2 SO4 followed by DEAE-cellulose, Sephadex G-200 and Sepharose 4B chromatography, was identified as alpha2-macroglobulin by using ultracentrifuge analysis and immunoelectrophoresis. The mechanism of interaction of beta-glucuronidase inhibitor with alpha2-macroglobulin was also studied.

Animals↗