Biomedical subjects
K Hata
Publications and source records attributed to K Hata.
Transvaginal Doppler ultrasound assessment of intratumoral hemodynamic change before and during hypertensive intra-arterial chemotherapy for uterine cancer.
OBJECTIVE: To evaluate blood flow in malignant uterine tumors during hypertensive intra-arterial chemotherapy. METHODS: Hypertensive intra-arterial chemotherapy (angiotensin II, cisplatin 100 mg, doxorubicin 40 mg) was given to two women with cervical cancer (stage IVA) and seven with endometrial cancer (three stage IA, one stage IB, two stage II, and one stage III). The intratumoral blood flow velocity waveforms were imaged by transvaginal Doppler ultrasound before and during the chemotherapy in six patients. RESULTS: The mean peak systolic velocity during hypertensive intra-arterial chemotherapy (58.9 +/- 29.3 cm/second) was significantly higher than that before chemotherapy (16.0 +/- 6.3 cm/second) (P < .05). There was a significant difference between the end-diastolic velocity before (5.2 +/- 1.8 cm/second) and during chemotherapy (21.2 +/- 6.8 cm/second) (P < .05). The resistance index value during hypertensive intra-arterial chemotherapy (0.607 +/- 0.094) fell significantly from that before therapy (0.644 +/- 0.119) (P < .05). Blood flow velocity waveforms in normal myometrial tissue could be recorded in three cases; in all, the diastolic flow noted before hypertensive intra-arterial chemotherapy disappeared during chemotherapy. CONCLUSION: These results suggest that hypertensive intra-arterial chemotherapy induces a selective marked increase of blood flow in uterine cancer.
A critical evaluation of transvaginal Doppler studies, transvaginal sonography, magnetic resonance imaging, and CA 125 in detecting ovarian cancer.
OBJECTIVE: To evaluate whether transvaginal Doppler ultrasound is more valid than transvaginal sonography, magnetic resonance imaging (MRI), and CA 125 in differentiating malignant from benign ovarian tumors. METHODS: Sixty-three patients with ovarian tumors (36 benign and 27 malignant) were studied with transvaginal Doppler ultrasound before surgery. Blood flow velocity waveforms arising from intratumoral and/or tumor surface arteries were assessed by calculating the resistance index. Transvaginal B-mode sonography and MRI imaging examinations were also conducted. Serum CA 125 levels were measured. RESULTS: There was a significant difference between the resistance index value (0.692 +/- 0.188) in benign tumors and the value (0.503 +/- 0.107) in malignant tumors (P < .05). When 0.72 (mean of the malignant tumor resistance index values + 2 standard deviations) was considered as the cutoff value of the resistance index, the sensitivity and specificity of the resistance index in detecting malignant ovarian tumors were 92.6 and 52.8%, respectively. These values did not differ significantly from those with transvaginal sonography diagnosis (sensitivity 85.2%, specificity 69.4%). The resistance index sensitivity was significantly higher than those with MRI diagnosis (66.7%) and CA 125 levels (59.3%) (P < .05); however, the resistance index specificity was significantly lower than those with MRI diagnosis (97.1%) and CA 125 levels (91.7%) (P < .05). CONCLUSION: Our results suggest that transvaginal Doppler ultrasound does not provide more useful diagnostic information than transvaginal sonography, MRI, and CA 125 for the differentiation of malignant from benign ovarian tumors.
Energetics of the fibrillating ventricle.
We have proposed a new mechanical index, equivalent pressure-volume area (ePVA), as a measure of the total mechanical energy of a fibrillating ventricle. ePVA is an analogue of the pressure-volume area (PVA) of a contracting ventricle and the specific area surrounded by the horizontal pressure-volume line at the pressure of ventricular fibrillation (VF) and the end-systolic and end-diastolic pressure-volume relations in the beating state in the pressure-volume diagram. In the isolated, cross-circulated heart preparation, we obtained myocardial oxygen consumption (VO2) during VF and ePVA at various left ventricular volumes in the control, epinephrine, propranolol and hypothermia runs. ePVA was highly linearly correlated with VO2 in all runs (r = 0.95, 0.98, 0.96 and 0.90, respectively). We also determined equivalent heart rate (eHR) as an estimate of the contraction frequency of individual myocytes in a fibrillating ventricle from mechanically unloaded VO2 in beating and fibrillating states. Using both ePVA and eHR, VO2 during VF was estimated and correlated with directly measured VO2. Estimated VO2 almost agreed with measured VO2 in all runs. We conclude that ePVA is a primary determinant of VO2 during VF, and that VO2 of a fibrillating ventricle can be reasonably accounted for by the combination of ePVA and eHR. This paper is a review of our previous studies on the energetics of a fibrillating ventricle.
[Effect of cefclidin and E1077, new cephalosporins, on the alcohol-metabolizing system in rats].
Administration of latamoxef and cefoperazone, reported to act like disulfiram in humans, caused a depression of mitochondrial low Km aldehyde dehydrogenase (low Km ALDH) activity in rats. In addition, a marked increase of blood acetaldehyde concentration was observed when rats were given alcohol orally at 18 hours after administration of these cephalosporins. However, mitochondrial low Km ALDH activity and blood acetaldehyde level were not altered by repeated administration of 300 mg and 1,000 mg of cefclidin (CFCL, E1040) or E1077 per kg. From these results, it was concluded that neither CFCLn or E1077 affected the alcohol metabolizing-system.
Incidence of other primary cancers in 1,569 patients with pharyngolaryngeal cancer and treated with radiation therapy.
From January 1977 through December 1989, a total of 1,569 patients with pharyngolaryngeal cancer (oropharynx: 240, nasopharynx: 221, hypopharynx: 246, and larynx: 862) were treated at the Department of Radiology, Osaka University Hospital and the Department of Radiation Therapy, The Center for Adult Diseases, Osaka. The incidence of other primary cancers in these patients was investigated using the data base of radiation therapy combined with information from hospital-based and Osaka prefectural cancer registries. One hundred and seventy-six of the 1,569 patients (11%) had other primary cancers (oropharynx: 21%, nasopharynx: 7%, hypopharynx: 13%, and larynx: 9%). The time of development of other primary cancers in more than 50% of the cases ranged between one year before and one year after the diagnosis of primary pharyngolaryngeal cancer. The expected number of the second primary cancer was estimated by multiplying the age-sex specific incidence rates for Osaka residents with person-years at risk based on Osaka prefectural cancer registry data. The observed/expected (O/E) ratios were 3.17 (p less than 0.01) for oropharyngeal, 2.01 (p less than 0.01) for nasopharyngeal, 2.16 (p less than 0.01) for hypopharyngeal and 1.10 (n.s.) for laryngeal cancer. The most common sites of the second primary cancer in order of frequency were: the oral cavity and pharynx, esophagus and lung for oropharyngeal cancer, the oral cavity and pharynx for nasopharyngeal cancer, the oral cavity and pharynx and the esophagus for hypopharyngeal cancer and the oral cavity and pharynx, esophagus and lung for laryngeal cancer.
Coherent soft-x-ray generation by the harmonics of an ultrahigh-power KrF laser.
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Systolic pressure-volume area (PVA) as the energy of contraction in Starling's law of the heart.
We have theoretically proposed "systolic pressure-volume area" (PVA) as a measure of total mechanical energy generated by ventricular contraction. We then experimentally showed that PVA closely correlates with left ventricular oxygen consumption (Vo2) regardless of ventricular loading conditions in a stable contractile state. Although Starling's law of the heart has been generally considered to describe the relation between ventricular preload as the input and the "energy of contraction" as the output, the energy of cardiac contraction has been variously identified with cardiac output, external work, contractile element work, tension-time index, etc., by different investigators. However, none of these variables has been unanimously accepted as the total mechanical energy of contraction because they do not consistently correlate with Vo2 which represents the total energy utilization for contraction. Considering the nature of PVA which has been revealed over the last decade, we now confidently propose that PVA is the most likely expression of the total mechanical energy of contraction that has been pursued for many years as the energy of contraction in Starling's law of the heart.
Maternal glucose loading and fetal cardiac function in humans.
Fetal cardiac function determined using M-mode echocardiography was studied subsequent to the maternal intravenous injection of 20 g of glucose. There were 11 appropriate for date infants (AFD), 7 noneventful, light for date infants (LFD) and one high risk fetus in severe toxemia of pregnancy (Case 1), at 32-40 weeks' gestation. The fetal heart rate showed no significant changes after glucose injection in each group. The left ventricular fractional shortening and cardiac output showed significant changes, whereas the right ventricular fractional shortening and cardiac output were unchanged in both AFD and LFD. In Case 1, the adverse change was noted in both left and right cardiac functions, as compared with AFD or LFD. The combined total cardiac output in AFD increased significantly at 5 min following glucose injection, whereas that in LFD did not change significantly. On the other hand, the combined total cardiac output in Case 1 decreased markedly at 5 min after glucose injection. These findings show that the glucose loading in the mother alters cardiac function in the fetus.
Preoperative diagnostic imaging of normal-sized ovary carcinoma syndrome.
We treated a patient with a massive amount of ascites, the cytology of which contained adenocarcinoma (class V). The left ovary was slightly enlarged and the preoperative diagnostic imaging (PDI) suggested the presence of a malignancy. The right ovary was of normal size and the PDI presented no evidence of malignancy. the intra- and postoperative histological diagnosis was serous cystadenocarcinoma of the right ovary and fibroma of the left ovary. Therefore, this case can be classified as one of a normal-sized ovary carcinoma syndrome. Difficulties involved in the preoperative diagnosis of this syndrome and drawbacks of PDI are discussed.
Transvaginal color Doppler imaging for hemodynamic assessment of reproductive tract tumors.
Transvaginal color Doppler flow imaging was carried out on 68 Japanese women (normal, 10; uterine myoma, 21; cervical carcinoma, 7; endometrial carcinoma, 10; benign ovarian tumor, 12; ovarian carcinoma, 8). Blood flow velocity waveforms were evaluated by calculation of the resistance index (RI). In 6 patients with cervical carcinoma neovascularization was evident within the cervix. In all patients with endometrial carcinoma such signs were present adjacent to and/or within the endometrium. These findings were absent in normal women and in those with myomata. There was a significant difference between the RI (0.510 +/- 0.097) in patients with cervical carcinoma and in normal women (0.881 +/- 0.048) in the ascending branch. In endometrial carcinoma the RI (0.535 +/- 0.158) was significantly lower in the arcuate artery compared to the normal uterus (0.768 +/- 0.075) and patients with uterine myoma (0.679 +/- 0.131), respectively. There was no area of neovascularization in the normal ovaries. Neovascularization was confirmed in four patients with a benign ovarian tumor and in all patients with an ovarian carcinoma. A significantly lower RI was obtained in cases of ovarian carcinoma (0.503 +/- 0.122) than in patients with benign ovarian tumors (0.888 +/- 0.216). Transvaginal color Doppler imaging and pulsed Doppler analysis may be useful diagnostic tools to differentiate benign and malignant tumors.
Ultrasonographic antenatal diagnosis of cavum veli interpositi.
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Fetal intracranial arterial hemodynamics assessed by color and pulsed Doppler ultrasound.
Fetal intracranial arterial velocimetries were serially performed on 31 pregnant women with regular menstrual cycle, at 28-40 weeks of gestation, using color and pulsed Doppler ultrasound. The change in fetal intracranial arterial hemodynamics was based on the calculation of resistance index (RI). There was no significant difference between the RI values in the anterior cerebral artery (ACA) and middle cerebral artery (MCA) from 28 weeks to term. The RI in the posterior cerebral artery (PCA) was significantly lower than that in the ACA and MCA, respectively, from 28 weeks to term (P less than 0.001). The PI values in both the ACA and MCA remained unchanged from 28 to 33 weeks, became significantly lower from 34 to 35 weeks (P less than 0.05), and the values were fairly constant thereafter. The RI seen in the PCA showed no significant change from 28 weeks to term. This color and pulsed Doppler ultrasound assessment of fetal intracranial arterial blood flow provides a useful foundation for elucidating normal intracranial hemodynamics and will aid in avoiding misinterpretations of the different intracranial arteries.
Enhancement of radiosensitizing effect of the nitroimidazole derivative RK28 on the proliferation of MethA tumor cells in combined use with diethyldithiocarbamate.
The radiosensitizing effect of the nitroimidazole derivative RK28 and diethyldithiocarbamate (DDC), which is an inhibitor of superoxide dismutase activity, was examined in vitro by using Meth A tumor cells. The radiosensitizing effect of 0.5 mM RK28 was observed in both of 10 Gy and 15 Gy irradiated groups. The addition of 5 x 10(-7) M DDC also enhanced the radiation-induced proliferation inhibition. Marked enhancement of the antiproliferative effect was observed in combined use of 0.2 mM or 0.5 mM RK28 with 2 x 10(-7) M or 5 x 10(-7) M DDC. These results suggest that enhanced oxygen effect could be expected through combined use of the ionizing irradiation with both of these agents.
Mass yield curves in low-energy proton-induced fission of 233U, 235U, 236U, 237Np, 239Pu, 242Pu, 244Pu, 241Am, and 243Am.
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External mechanical work during relaxation period does not affect myocardial oxygen consumption.
We assessed the effect of external mechanical work (EW) during the relaxation period (RP) on myocardial oxygen consumption (VO2) and clarified the energetic significance of the potential energy (PE) portion of the pressure-volume area (PVA) in the cross-circulated dog left ventricle. We changed the course of the relaxation segment of the pressure-volume (P-V) trajectory by increasing or decreasing EW within a given PVA without changing the end-diastolic volume (EDV) and the systolic segment of the P-V trajectory while measuring VO2. Thus the ventricle underwent ejection or filling during RP. Although the percent fraction of EW in PVA (%EW/PVA) was markedly increased from 32 +/- 12 (SD) to 93 +/- 3% in ejecting contractions (8 hearts) and from 0 to 93 +/- 5% in isovolumic contractions (3 hearts), these marked changes in %EW/PVA did not significantly affect VO2. Moreover, the VO2-PVA data during these procedures fell on the reference VO2-PVA relation line obtained by changing EDV and PVA of isovolumic contractions. We conclude that EW during RP at a constant PVA does not affect VO2 and part of PE can be converted into EW in an energetically equivalent manner.
Preoperative diagnostic imaging of primary vaginal carcinoma by transvaginal color Doppler and magnetic resonance imaging.
We treated a patient with primary vaginal carcinoma. Very valuable preoperative diagnostic imaging of the carcinoma obtained by transvaginal color Doppler and magnetic resonance is reported herein.
Transvaginal color and pulsed Doppler ultrasound evidence of hemodynamics of the female pelvis.
Transvaginal color and pulsed Doppler ultrasound examinations were made on 40 patients to assess hemodynamics in the pelvis. Use of a special probe for transvaginal scanning led to superb simultaneous visualization of structures and blood flow, and we noted various events, even in the small, deep and/or peripheral vessels. Some but not all of the observations were in agreement with the results obtained using transabdominal color and pulsed Doppler ultrasound. We propose that transvaginal color and pulsed Doppler ultrasound be considered for routine use to determine physiological and pathological events in the female pelvis.