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Biomedical subjects

H Tsukada

Publications and source records attributed to H Tsukada.

259 records · Page 15Linked to original sources

Effect of chromium(III) on nucleolar RNA synthesis.

The enhancement of hepatic nucleolar RNA synthesis induced by Cr(III) in partially hepatectomized rats and its mechanisms are described. Cr(III)-administered (0.5 mg Cr/kg, ip) and then partially hepatectomized rats were significantly enhanced in the hepatic nucleolar RNA synthesis at the very early stage of liver regeneration. This enhancement was caused both by the induction of newly found nucleolar Cr-bound protein of 70 kD (Cr-p70) and by the activation of nucleolar chromatin, both of which arose from nuclear accumulation of Cr together with partial hepatectomy. Studies on the mechanism of this enhancement indicated that the Cr-p70 bound to the activated nucleolar chromatin and loosened its higher-order structure, resulting in an increase of the B-form fraction of chromatin DNA. The degree of this loosening well correlated with the amount of Cr-p70 bound to chromatin and also with the extent of elevation of RNA synthesis. Some molecular species of nonhistone proteins in chromatin were found to play an important role in the interaction to Cr-p70. These results suggest a possibility that the action of Cr is involved in cell proliferation process.

Animals↗

Whole-body positron emission tomography and tumor marker CA125 for detection of recurrence in epithelial ovarian cancer.

We evaluated the clinical role of the combination of positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) and tumor marker CA125, in the detection of recurrence after initial therapy for epithelial ovarian cancer. The indication is the cases that cannot be confirmed the recurrence by conventional imaging modalities. Ninety patients underwent PET and computed tomography, including the measurement of specific tumor markers. FDG-PET confirmed recurrence in 46 patients (51%), and the recurrent site was confirmed by PET alone in 17 (37%). PET had high sensitivity for detecting both intraperitoneal and retroperitoneal metastases (93.9 and 92.9%, respectively). PET imaging was able to detect normal-sized metastases in the lymph nodes in 14 (50%) of the 28 patients with retroperitoneal metastasis. PET could show 87.5% positive rate of recurrent patients with asymptomatic rise of CA125 who had no sign of recurrence by conventional imaging methods. Of the 46 recurrent patients, 41 (89%) had specific elevated titers of CA125 at the first treatment. PET imaging was able to detect recurrence at relatively low titers (a median 68 U/mL) of CA125. In 8 (19.5%) of these 41 patients, recurrence with normal CA125 levels could be confirmed only by PET. The sensitivity of the combination of PET and CA125 was 97.8% with only one false-negative case. The combination of FDG-PET and CA125 titer is useful for the accurate detection of recurrence.

Adenocarcinoma↗

Whole-body positron emission tomography with F-18 fluorodeoxyglucose for the detection of recurrence in uterine sarcomas.

We evaluated the usefulness of whole-body positron emission tomography (PET) using F-18 fluorodeoxyglucose (FDG-PET) for the detection of recurrence in follow-up patients after primary treatment of uterine sarcoma. Eight patients with pathologically proven uterine sarcoma underwent FDG-PET, computed tomography (CT), and ultrasonography (US). Final diagnoses of recurrence were established in five cases (three carcinosarcomas and two leiomyosarcomas). PET revealed recurrent sites in the intraperitoneum, liver, lung, bone, and retroperitoneal lymph nodes. However, the minimum size of the tumor detected by PET depended on the sites of recurrence. CT and US images showed two false-negative cases of intraperitoneal tumors. PET was able to detect a solitary small intraperitoneal tumor, which was very difficult to detect by CT and US. Positive PET findings did not affect the prognosis in three of the five recurrent patients; however, the remaining two patients consequently underwent the combination therapy consisting of surgery and chemotherapy and survived for more than 1 year after the positive FDG-PET results. Application of PET imaging for the early detection of recurrent sites was useful for the decision of treatment strategy for patients with recurrent uterine sarcoma.

Adult↗

Cloudy nodule on HRCT: a new clinico-radiologic entity of pulmonary adenocarcinoma.

We propose cloudy nodule (CN) on HRCT as a special type of pulmonary adenocarcinoma. CN was defined as a cloudy nodular shadow in the peripheral part of the lung with lower density than pulmonary vessels on HRCT. Radiologic images of nine CNs in eight cases were correlated with the pathological findings of the resected specimen. All CNs were clearly demarcated on HRCT. They were pathologically composed of well differentiated adenocarcinoma, mainly bronchioloalveolar type with little or no central scar. Plain films were negative in six of nine cases. CN on HRCT may indicate well-differentiated adenocarcinoma with good prognosis.

Adenocarcinoma, Bronchiolo-Alveolar↗

Classification of air density areas in CT-pathologic correlation of pulmonary adenocarcinoma.

Air density areas (ADAs) such as air bronchogram, bubble-like area, and cavity on high resolution computed tomography (HRCT) of pulmonary adenocarcinoma were examined to clarify their pathological implications. Forty-two resected specimens of pulmonary adenocarcinoma were histopathologically examined in correlation with the HRCT findings with particular emphasis on ADAs. Forty-one ADAs observed in 32 of 42 cases with pulmonary adenocarcinoma were classified into three types: air bronchogram type (n = 22), bubble-like area type (n = 12), and cavity type (n = 8). Twenty of 22 air bronchogram ADAs corresponded to bronchi. Nine of 12 bubble-like area ADAs corresponded to bronchioles. Only one of eight cavity-ADAs consisted of necrosis. The classification of ADAs in pulmonary adenocarcinoma is considered to be useful in interpreting HRCT findings of pulmonary nodules.

Adenocarcinoma↗