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R Koga

Publications and source records attributed to R Koga.

50 records · Page 3Linked to original sources
PubMed1988

Preparation of protein components exhibiting myosin light chain kinase activities from bovine aorta: discrepancies between its enzyme activity and actomyosin activating effect.

1) Two protein components, 155 and 130 kDa in their electrophoretic molecular weights, respectively, were isolated in a homogeneous state from bovine aorta; they showed both the superprecipitation-inducing effect on desensitized natural actomyosin and the myosin light chain kinase (MLCK) action on gizzard myosin. 2) The superprecipitating activity of the 155 kDa component was 5 time higher than that of the 130 kDa component on the basis of equivalent MLCK activity. 3) The same procedure was applied to bovine stomach, giving rise to a 155 kDa component in a homogeneous state as in the case of aorta, but the 130 kDa component thus prepared was contaminated by higher molecular weight components. 4) If compared on the basis of equivalent MLCK activity, bovine stomach 155 kDa component showed more than 10 times higher superprecipitating activity than the fraction that contained the 130 kDa component as the main constituent. 5) The discrepancy between the superprecipitating activity and MLCK activity mentioned above was discussed in relation to the Ca2+ regulation mechanism in smooth muscle contraction. The possibility that the 130 kDa component might be a proteolytic product of the 155 kDa component was also discussed.

Actomyosin↗
PubMed1985

[A study on factors influencing survival in stage I ovarian cancer].

Early diagnosis is difficult in ovarian cancer and the prognosis is unfavorable even in stage I case. A total of 131 cases with stage I ovarian carcinoma were treated at our institution, 73 were stage Ia, 13 were stage Ib, 45 were stage Ic and 39 were LPM. To define the criteria for selection of therapy, we retrospectively reviewed the stage I ovarian cancer. The results were as follows: The best survival rate was demonstrated in 96% of LPM cases followed by 73% of endometrioid adeno-carcinoma. Cases with rupture of capsule and with ascites at surgery influenced the 5 year survival rate. We observed no difference in survival rate between the conservative operation (unilateral salpingo-oophorectomy) group and the complete operation (bilateral salpingo-oophorectomy and total hysterectomy) group. Those who had received postoperative chemotherapy showed the longest survival rate of 86%. Evaluation of deaths; 9 of 21 with stage Ic died within 12 months after surgery, and 4 of 7 with stage Iai between 1 and 3 years. The analysis has shown the importance of adequate postoperative treatment and of strict follow-up to guard against recurrence of malignancy in patients with ruptured tumor capsules as well as in those with ascites.

Adenocarcinoma↗
PubMed1984

[Clinical significance of new tumor marker CA 125 in gynecological cancer--particularly usefulness in diagnosis of ovarian cancer].

A concentration in sera of a new antigen CA125 related to cancer of the ovary was measured by radioimmunoassay which used a monoclonal antibody, and its usefulness as a tumor marker in the diagnosis of cancer of the ovary was investigated. The mean values for CA125 in sera of healthy controls (80 females) were 14.2 +/- 12.2 U/ml. Mean values for CA125 in sera of various patients were 29.0 +/- 39.6 for myoma uteri (30 cases), 26.7 +/- 30.1 for benign ovarian tumors (10 cases), 64.4 +/- 146.2 for cervical carcinoma (14 cases), and 31.5 +/- 19.8 for endometrial carcinoma (6 cases), whereas the mean values for ovarian cancers (23 cases) were as high as 311.3 +/- 250.4. On the other hand, positive rates for CA125, when the cut-off value was set to 65 U/ml, were 1.3% for healthy controls (1 out of 80 cases), 10.0% for myoma uteri (3 out of 30 cases), 10.0% for benign ovarian tumors (1 out of 10 cases), 14.3% for cervical carcinoma (2 out of 14 cases), and 16.7% for endometrial carcinoma (1 out of 6 cases), whereas the positive rate for ovarian cancers was 78.3% (18 out of 23 cases). Especially for serous cystadenocarcinoma, the positive rate was 100% (10 out of 10 cases). From the above, the measurement of CA125 in sera was considered to be significant in the diagnosis of ovarian cancer.

Adolescent↗