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Biomedical subjects

K Koga

Publications and source records attributed to K Koga.

At least 289 records · Page 16Linked to original sources
PubMed1983

Total body irradiation as a primary treatment for adult T-cell leukemia.

Adult T-cell leukemia (ATL) is an extremely difficult disease to treat. The median survival of patients with this disease has been reported to be only about 3 mo even with intensive treatment. We have treated five ATL patients (four males and one female, 42 to 72 yr of age) with total body irradiation (TBI). One patient who received 150 rad of TBI achieved complete remission and has been well without treatment for over a year. One hundred and thirty rad of TBI was administered to another patient, resulting in control of the leukocyte count at around 10,000/microliter and survival for 6 mo. Three patients received 100 rad of TBI. Only one of these patients has lived with leukemic cells for over a year without treatment. The other two patients relapsed rapidly and despite various kinds of treatment, such as a second course of TBI, extracorporeal irradiation of the blood, cytapheresis and combination chemotherapy consisting of pepleomycin, vincristine and a high dose of prednisolone, expired from pneumonia in 3 and 4 mo respectively. In all except the last two patients, thrombocytopenia and anemia developed and lasted for 2.5 wk to 3 mo and granulocytopenia occurred only in the patient who received 150 rad of TBI. Slight nausea and loss of appetite were noticed in one patient. It seems that 100 to 150 rad of TBI is effective against ATL, with acceptable side effects.

Adult↗
PubMed1983

[Results of radiation therapy for cancer of the uterine cervix].

Fifty-four patients with carcinoma of the cervix uteri were treated with external irradiation and high-dose intracavitary irradiation according to their clinical stage. The 4-year relative survival rate was 86.6% in stage I patients, 77.9% in stage II, 55.4% in stage III and 0% in stage IV. The incidence of radiation injury was: perforation of the intestine, 2 cases; vesico-vaginal fistula, 2 cases; recto-vaginal fistula one case; stenosis of the rectum or sigmoid, 2 cases. This suggests that severe complications may occur in reirradiated cases or cases irradiated with more than 7 fractions of intracavitary irradiation. The optimal radiation dose seemed to be 2,400 to 3,000 rad at point A with a fraction dose of 600 rad a week, combined with whole pelvis irradiation of 3,000 to 4,000 rad.

Adenocarcinoma↗
PubMed1983

[Radiotherapy for anaplastic esophageal cancer].

We report our experience with radiation therapy in 2 patients with anaplastic esophageal cancer with extensive distant metastases. Radiotherapy was given to the primary esophageal lesions and in both patients the tumors completely disappeared after irradiation with 2000 to 3000 rads. However, the metastatic lesions of the bone and liver did not respond despite the administration of BLM + PT -207 + BEMP in one case and METVFC + FT -207 in the other. Both patients died 4 and 5 months, respectively, after beginning the treatment. Effective chemotherapy of metastases needs to be developed because the primary lesions of anaplastic esophageal cancer are highly sensitive to radiation therapy.

Aged↗
PubMed1983

[Radiotherapy for post-operative inflammatory breast cancer].

Two patients with inflammatory breast cancer treated with a combination of radical mastectomy, irradiation, and immunochemotherapy are reported. After radical mastectomy, both patients were given a dose of 4000 rad and 5000 rad to the chest wall and parasternal lymph nodes, and 5000 rad to the axillary and supraclavicular lymph nodes. However, both patients died of recurrence within the irradiated field of the chest wall and metastatic spread to the neighbouring skin. A discussion on the dose and field in radiation therapy for inflammatory breast cancer is presented.

Adenocarcinoma↗
PubMed1982

Phospholipase C activity in egg yolk sac of Japanese quail during embryonic development.

1. The amount of lipid decreased markedly at the later stage of embryonic development, coinciding with the remarkable decrease in yolk weight. 2. Phospholipase C activity in the yolk sac appeared on the 6th day of incubation and increased markedly as incubation proceeded. 3. The enzyme showed its optimum activity at pH 9.5 and at 40 degrees C. 4. The activity was enhanced 2-fold by 20 mM CaCl2 and by 40% by 4 mM deoxycholate but inhibited by 2 mM ZnCl2 and CuSO4.

Animals↗
PubMed1982

Further physicochemical studies on the complex formation between iron-sulfur proteins and flavoproteins from spinach chloroplast and beef adrenal cortex electron-transfer systems.

Physicochemical experiments were performed in order to get further evidence of the formation of complexes between iron-sulfur proteins and flavoproteins from spinach chloroplast and beef adrenal cortex electron-transfer systems. With both spinach and adrenal iron-sulfur protein-flavoprotein systems, characteristic difference circular dichroism (CD) spectra between the sum of CD spectra of the respective proteins and the CD spectrum of a mixture with a molar ratio of one to one were obtained in the visible and far-ultraviolet regions. By differential scanning calorimetry (DSC) measurements, ferredoxin and ferredoxin-NADP reductase were found to be stabilized against heat treatment upon mixing: (1) the apparent denaturation temperatures of ferredoxin and the reductase increased by about 18 and 5 degree C, respectively, and (2) the activation energy of the denaturation reaction increased by about 50%. These results lead to the conclusion that the iron-sulfur protein and flavoprotein from a tightly bound complex, and suggest that the complex formation alters both the environments of the iron-sulfur and flavin chromophores and the contents of the ordered structures, resulting in stabilization of the proteins.

Adrenal Cortex↗
PubMed1980

Dynamical structure of phosphatidylcholine molecules in single bilayer vesicles observed by nitrogen-14 nuclear magnetic resonance.

A 14N nuclear magnetic resonance (NMR) study of lecithins, 24-65 degrees C for dipalmitoylphosphatidylcholine (DPPC) and 20-50 degrees C for egg yolk phosphatidylcholine (EPC), in single bilayer vesicles prepared by an ultrasonic method is reported. Choline 14N signals are found to be Lorentzian in these systems of definite molecular arrangement because of the smallness of the quadrupole coupling constant. This is due to the high symmetry around the trimethylammonium type nucleus and to the low ordering compared with thermotropic liquid crystals. An analysis of relaxation times T1 and T2 gives the following results. (1) The activation energies for the rapid local motion of C beta-N bonds are 36 and 31 kJ.mol-1 for DPPC and EPC, respectively. These are higher than that of a C alpha-D bond, indicating that the -N+(CH3)3 group is bound in the polar surface. (2) The vesicle radius seems to decrease toward higher temperatures, just below the start of the phase transition. (3) The lateral diffusion coefficient of the constituent lipid is obtained with the help of the Stokes radius. The 14N NMR techniques has the essential advantage of applicability without modification of the system.

Egg Yolk↗
PubMed1980

Radiosensitive meningioma.

A hugh intracranial angioblastic meningioma responded well to preoperative irradiation. The indication for preoperative irradiation of hypervascular and inaccessible meningiomas is discussed.

Adult↗