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Biomedical subjects

K Hata

Publications and source records attributed to K Hata.

At least 379 records · Page 21Linked to original sources

Glutathione depletion by 2-nitroimidazole-1-acetohydroxamic acid as a radiosensitizer in hypoxic rat hepatocytes.

The effects of nitroimidazoles as radiosensitizers on intracellular glutathione (GSH) level were investigated in rat isolated hepatocytes. Dinitroimidazoles have lowered almost completely GSH level during the incubation for 30 min under oxic (95% O2+5% CO2) condition, while mononitroimidazoles had scarcely affected. In the case of hypoxic (95% N2+5% CO2) condition, however, 2-nitroimidazoles, not 4-nitroimidazoles, as well as 2,4- and 4,5-dinitroimidazoles have caused the significant depletion of GSH. This suggests that nitro group in the 2-position of imidazoles may be responsible for the GSH depletion under hypoxia. Especially, 2-nitroimidazole-1-acetohydroxamic acid (KIH-801) was found to be the most potent GSH depletor only under hypoxic, not oxic conditions, and might be useful for the new hypoxic cell radiosensitizer instead of misonidazole.

Animals↗

[Evaluation of female intrapelvic blood vessels and their hemodynamics with real-time two-dimensional Doppler ultrasound].

Real-time two-dimensional and pulsed Doppler ultrasound examinations were performed on 5 healthy Japanese with a history of normal menses and 27 pregnant subjects with regular menstrual cycles and no complications. The objective of the study was to visualize blood flow and record blood flow velocity waveforms from the pelvic vessels. This approach led to an accurate estimation of blood flow in a non-invasive manner. No particular technical skill or training is required. The resistance index of the arcuate artery was high in non-pregnant subjects and in those in early pregnancy. By 15 weeks the index became low and there was little change thereafter. We propose that real-time two-dimensional and pulsed Doppler ultrasound will prove to be good diagnostic tools for the detection of various pathologies encountered in the field of obstetrics and gynecology.

Female↗

Radiation therapy combined with or without chemotherapy for limited extent of non-small cell lung carcinoma.

From July 1977 to December 1983, 130 patients with limited extent of non-small cell lung carcinoma received radiotherapy of more then 30 Gy combined with or without chemotherapy at the Center for Adult Diseases, Osaka, Japan. Four treatment arms were evaluated: RT alone, RT following chemotherapy, RT following low dose concurrent irradiation with chemotherapy (LDC-RT), and RT concurrently used with chemotherapy. Complete regression of local and regional tumor was produced in 5% and partial regression 58%. Among these four treatment arms LDC-RT showed the highest response rate (88%), while no difference in long-term survival was apparent. According to the RT dose, survival of cases who received RT doses above 50 Gy was better than that of cases under 50 Gy in spite of the combination with chemotherapy. These data suggest that adjuvant chemotherapy has no favorable impact against the survival. Concerning the prognostic factor, tumor response after treatment, general performance status and N stage were important.

Antineoplastic Combined Chemotherapy Protocols↗

[Extracorporeal shock wave lithotripsy with EDAP LT-01 lithotriptor].

Extracorporeal shock wave lithotripsy (ESWL) by EDAP LT-01 was used to treat 77 patients with upper urinary tract stones. A total of 218 sessions were performed for 111 stones in 52 kidney units and 41 stones in 37 upper ureter units, and 77% of the 52 kidney stone units and 62% of the 37 ureter units were completely disintegrated. The success of fragmentation of kidney stones differed with the size of the stone, 96% of the stones less than 21 mm and 63% of the 8 stones between 21 and 30 mm were successfully fragmented. The success of fragmentation of ureteral stones differed auxiliary manipulation. Eighty-one percent of the 21 ureteral stones moved into the kidney, were successfully disintegrated, but 40% of the 20 stones unmoved could be disintegrated with retrograde manipulation. Of the 62 successful units, 89% became stone free within 3 months. Complications were subcapsular renal hematoma in 3 patients and obstruction in 5 patients. The initial 25 patients were treated under epidural anesthesia and 52 patients were treated without anesthesia. The results show that the indication of ESWL with LT-01 is better for the stones smaller than 30 mm and the indication should be determined after a couple of sessions for stones greater than 30 mm. ESWL with LT-01 can be performed on an out-patient basis without anesthesia in many cases.

Adolescent↗

Intracardiac blood flow velocity waveforms in normal fetuses in utero.

Sixty-five continuous-wave Doppler ultrasonographic examinations were performed on 57 normal fetuses at 16 to 40 weeks of gestation. Maximal velocities of transmitral, transtricuspid, transaortic and transpulmonary blood flow velocity waveforms were assessed. Transmitral maximal velocity, transtricuspid maximal velocity, transaortic maximal velocity and transpulmonary maximal velocity correlated well with gestational age. The ratio of transtricuspid maximal velocity/transmitral maximal velocity was at least 1 in 44 of 45 fetuses (97.8%). In the ratio of transpulmonary maximal velocity/transaortic maximal velocity, the characteristic change was not evident. Therefore, continuous-wave Doppler ultrasonographic measurement of fetal intracardiac blood flow velocity waveforms in utero can aid in analyzing the physiologic circulatory hemodynamics.

Blood Flow Velocity↗

Fetal liver measurements by ultrasonography.

A total of 378 measurements of fetal liver size were made from 18 weeks gestation through term. Statistical analysis of the results showed a highly significant correlation between fetal liver measurements and gestational age, biparietal diameter, and fetal femur length (R = 0.93, R = 0.89, R = 0.89, respectively). Ultrasonic measurement of the fetal liver is a reliable indicator of fetal growth in the third trimester, as growth rates of the biparietal diameter and head circumference are blunt. Furthermore, consecutive measurements of fetal liver size enhance the detection of symmetrical, fetal growth, by acquisition of various ultrasonic parameters such as biparietal diameter, fetal femur length, fetal abdominal circumference and so forth.

Embryonic and Fetal Development↗

High-dose rate intracavitary therapy for carcinoma of the uterine cervix: I. General figures of survival and complication.

From August 1978 through December 1982, a total of 200 patients with previously untreated carcinoma of the uterine cervix were treated using remote afterloading high-dose rate intracavitary therapy (RALS) at our department. According to the staging of UICC (1978), 8 patients were classified into Stage Ia, 22 Ib, 22 IIa, 53 IIb, 85 III, and 10 IV. Actuarial 5-year survival rates by Stage were 100% in Stage Ia, 86% Ib, 67% IIa, 72% IIb, 41% III, and 20% IV (p = 0.0001). Significant prognostic factors in Stage II were the value of hemoglobin (p = 0.0115) and age (p = 0.0431) by logrank test. Corresponding factors in Stage III were the value of hemoglobin (p = 0.0005) and total protein (p = 0.0036). Late complications after RALS developed in 22 patients (11%), that is, rectum 14 (7%), bladder 6 (3%), small intestine 4 (2%) and sigmoid colon 1 (1%). Severe complications requiring surgery were noted in 7 patients (4%). There was no fatal case attributable to complication. It is concluded that RALS is one of the most effective and safe means for the treatment of carcinoma of the uterine cervix based on our results.

Brachytherapy↗

Renal arterial blood flow velocity waveforms in pregnant women.

Seventy-two continuous-wave Doppler ultrasonographic examinations were performed on nine nonpregnant and 56 normal pregnant women. The range of gestation was 6 to 40 weeks, and the objective was to record the renal arterial blood flow velocity waveform. Acceleration time and systolic per diastolic ratio of renal arterial blood flow velocity waveforms were assessed. Of 72 examinations, 68 recordings were made of the left renal artery (94.4%) and 28 of the right renal artery (38.9%), respectively. There was no correlation between acceleration time and systolic per diastolic ratio and gestational age, respectively, and no correlation between acceleration time and systolic per diastolic ratio, and caliceal diameter of the renal pelvis, respectively. Acceleration times of the left and right renal arteries were 47 +/- 11 and 40 +/- 8 msec in nonpregnant women and 62 +/- 23 and 62 +/- 23 msec in pregnant women, respectively. The left and right systolic per diastolic ratios were 3.1 +/- 0.7 and 2.9 +/- 0.5 in nonpregnant women and 2.8 +/- 0.6 and 2.6 +/- 0.5 in pregnant women, respectively. Therefore these data provide a foundation for the study of hydronephrosis, which may occur in pregnant women.

Blood Flow Velocity↗

Ultrasonographic assessment of fetal adrenal gland and placenta: correlation with estrogen in maternal urine.

Forty-eight ultrasonographic examinations done to assess growth of the fetal adrenal gland and placental aging were performed on 17 normal fetuses and 7 fetuses with intrauterine growth retardation (IUGR). Gestational age ranged from 30 to 40 weeks. High correlations of the area of fetal adrenal gland (FAGA) with gestational age were noted in the normal fetuses (r = 0.96, p less than 0.001) and IUGR (r = 0.93, p less than 0.001), respectively. FAGA correlated well with the level of estrogens in the maternal urine (r = 0.65, p less than 0.001). When the value of FAGA was 300 mm2 and over, the level of estrogens in the maternal urine was 20 mg/day and over, and all were normal fetuses. In cases of grade I and II placentas, the mean values of FAGA in normal fetuses were larger than those in IUGR, respectively (p less than 0.001). In the case of IUGR with placental infarction and hematoma associated with severe toxemia of pregnancy, the FAGA was significantly small.

Adrenal Glands↗

Ultrasonographic measurement of the human fetal liver in utero.

A total of 232 measurements of the size of the human fetal liver were made from 19 weeks gestation through to term. The size of the liver increased linearly with the advance in pregnancy. Statistical analyses showed a highly significant correlation between liver circumference and area and gestational week or fetal abdominal circumference (r = 0.89, r = 0.90, r = 0.90, r = 0.85).

Abdomen↗

Ultrasonographic identification of the human fetal gallbladder in utero.

Ultrasonographic studies of the human fetal gallbladder were performed in utero on 149 fetuses ranging from 20 to 39 weeks of gestation. The gallbladder could be identified in 37.5% (20-23 weeks) to 64.7% (24-27 weeks) after 20 weeks of gestation. The normal sonographic characteristics of the fetal gallbladder were described and the area of fetal gallbladder, the length and the width were measured, respectively. The ultrasonographic identification of the fetal gallbladder is a first step in antenatal detection of congenital anomalies affecting the gallbladder.

Female↗

Ultrasonographic in utero identification and measurement of the normal fetal spleen.

Sixty-nine ultrasonographic examinations were performed to identify and measure the fetal spleen in utero on 49 women with regular menstrual cycles, at 18-41 weeks of gestation. The length (FS-L), width (FS-W), area (FS-A), and sectional area (length X width; FS-LW) of the fetal spleen correlated well with the gestational age. A very high correlation of FS-LW with FS-A was noted (r = 0.98; p less than 0.001). Ultrasonographic identification and measurement of the fetal spleen in utero is thus a useful indicator of fetal spleen growth and should facilitate detection of in utero splenomegaly, asplenia and other abnormalities.

Female↗

Ultrasonic evaluation of trophoblastic disease and the response to chemotherapy.

Ultrasound is an established method of confirming the presence of a hydatidiform mole in utero. However, in agreement with other investigations, we have often noted that the appearance of this entity is less specific than originally reported. To elucidate this, the ultrasonic patterns of 26 patients with trophoblastic disease and 27 with other entities were reviewed. Since there is a paucity of literature with regard to the response of choriocarcinoma to chemotherapy, determined by ultrasound, we simultaneously studied the relationship between findings of the ultrasonograms and the levels of hCG-beta-subunit in sera. We noted variable ultrasonic features in trophoblastic disease, and the sonograms of the choriocarcinoma have occasionally been confused with those of hydatidiform mole. If special attention is directed to the thickness of the placenta-like echoes as well as the sonolucent areas within it, the diagnosis of partial hydatidiform mole may be feasible. We also noted a rough correlation between ultrasonic appearances and the hCG-beta-subunit value, determined during chemotherapy for choriocarcinoma.

Chorionic Gonadotropin↗