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Biomedical subjects

T Ishida

Publications and source records attributed to T Ishida.

At least 1,351 records · Page 75Linked to original sources

Clinico-epidemiologic study of stroke in Akita, Japan.

An analysis was performed of 2,168 consecutive stroke patients who were examined by computed tomography and entered into a hospital-based stroke registry in Akita Prefecture, Japan. The occurrence of cerebral hemorrhage, cerebral infarction, and subarachnoid hemorrhage was 30, 55, and 14%, respectively. Age-specific rates of subarachnoid hemorrhage were higher in women than men; other types of stroke showed a preponderance in men. Total strokes increased in the winter; this seasonal difference was confined to cerebral hemorrhage. Putaminal hemorrhages predominated in the younger age groups; thalamic hemorrhage and cerebellar hemorrhage were predominant in the older age groups. The increased accuracy of the diagnosis of stroke subtypes by the use of computed tomography in this study is in contrast to other community-based epidemiologic studies that have relied solely on clinical diagnosis. This increased accuracy is seen to be the reason that new ratios of stroke subtype incidence have been identified.

Cerebral Hemorrhage↗

Deep-heating characteristics of an RF capacitive heating device.

An RF capacitive heating device was constructed and its deep-heating characteristics were studied using three mini-pigs. The deep-heating ability of RF capacitive heating was found to be improved by enlarging the electrodes, driving at 8 MHz, cooling the skin under the electrodes, inserting a bolus between the body and the electrodes and considering the anatomical structure of the body. The heating characteristics obtained were as follows. When applicators were placed on both sides of the abdomen of a mini-pig, 7 mm in fat layer thickness and 23 cm in lateral chest thickness, the increase in temperature of the deep part was greater than that of the fat layer. When applicators were placed on the posterior and anterior abdomen, overheating was noted in the fat and muscle near the back. The temperature was highest in a mock tumour, made by blocking blood flow to the spleen. The bio-heat equation revealed that RF capacitive heating accompanied by surface cooling at 10 degrees C could heat the deep portion of the body to 42 degrees C without excessive heating of a 1.6 cm thick fat layer.

Abdomen↗

Development of inductive heating equipment using an inductive aperture-type applicator.

We designed an inductive aperture-type applicator, IATA, consisting of a one-turn, square, column-like coil made of a metal strip. In experiments using a phantom, this applicator was seen to have the following characteristics: (1) it does not excessively heat the fat layer; (2) deep portions can be heated effectively; (3) heat can be applied to the subject, without contact with the applicator; (4) excessive generation of heat does not occur in parts of tissue near the edge of the aperture; (5) size of the aperture can be changed for adaptation to size of the site to be heated; (6) the aperture can be modified to fit the shape of the subject and the depth of penetration is influenced by size of the subject being heated; (7) the applicator can be driven at an arbitrary frequency; (8) efficiency of heat generation to the input power is low. The inductive heating equipment, 'Inductron', which we have developed possesses the necessary requirements for adequate clinical application.

Adipose Tissue↗

A new applicator utilizing distributed electrodes for hyperthermia: a theoretical approach.

We propose a new type of applicator for hyperthermia namely a Distributed Electrodes Applicator. Many electrodes are fixed on boli below which the patient is placed. A set of RF with optimized amplitudes and phases is supplied to the electrodes so as to minimize the ratio of SAR (specific absorption rate) in the fat layers to that in the central region of the patient. SAR patterns in a heated material were calculated using two-dimensional finite element method, and the results showed that the proposed applicator can heat the deep portions of the patient without excessive heating of the fat layers.

Electrodes↗

Prognostic significance of p21waf1, cyclin D1 and retinoblastoma expression detected by immunohistochemistry in non-small cell lung cancer.

p21waf1 is a downstream effector of p53, and mediates growth arrest by inhibiting the action of G1 cyclin-dependent kinases. Cyclin D1 is a cell-cycle regulator essential for G1 phases progression and a candidate proto-oncogene implicated in the pathogenesis of several human tumor types. Cyclin D1 overexpression and the absence of retinoblastoma (Rb) protein have been frequently seen in various types of cancer, including lung cancer. The aim of this study was to clarify the relationship between the expressions of p21waf1, cyclin D1, and Rb protein, and to investigate the correlation between these protein expressions and the clinical features of the patients, and their prognoses. We immunohistochemically examined 92 samples of resected non-small cell lung cancer for p21waf1, cyclin D1, and Rb expression. Of the 92 specimens examined, 43 cases (46.7%) showed p21waf1 expression, 23 cases (25.0%) showed cyclin D1 overexpression, and 61 cases (66.3%) showed Rb expression. No correlation was observed between the expressions of p21waf1, cyclin D1, and Rb. There was no association of p21waf1 and cyclin D1 immunoreactivity with gender, disease stage, or histological types of the tumor. Regarding the prognosis in 79 cases with complete resection, no statistical differences were observed according to the degree of expression of these three factors. However, when unfavorable prognostic factors were considered to be the positive expression of p21waf1, positive of cyclin D1, and negative of Rb, the 5-year disease-free survival rate in the group with 2 or 3 unfavorable prognostic factors was 21.1%, which was statistically poorer than the 45.4% in the group with 0 or 1 unfavorable prognostic factor (p=0.0138). We conclude that examination of the expression of cell cycle regulators, such as p21waf1, cyclin D1, and Rb, is useful as a prognostic indicator, when these proteins' expression is analyzed in combination.

Adult↗

Hepatic resection under selective portal vein occlusion using degradable starch microspheres. A simple procedure of an experimental study using the pig.

A simple technique is described to perform hepatectomy. The technique consists of portal vein blood flow occlusion using degradable starch microspheres injected through an ultrasonically-guided puncture at the point of resection root and hepatic artery occlusion. The method minimizes ischemic damage to the liver remnant and is easy to perform.

Animals↗

Vascular invasion of early gastric cancer at resection line.

Vascular invasion is observed in early gastric cancers (EGCs) as well as advanced gastric cancers. However, there have been no studies assessing adequate surgical margins for EGCs with reference to vascular invasion. A total of 452 EGCs were retrospectively evaluated. Vascular invasion, via lymphatics and/or venous vessels, was examined histologically. The distance from the tumor edge to infiltration was measured when cancer cells extended beyond the tumor through vessels. Vascular invasion was histologically confirmed in 41 EGCs (9.1%). Invasion was in one-fourth (40/166, 24.1%) of submucosal cancers, but in only one (1/286, 0.3%) mucosal cancer. Five EGCs (1.1%) showed infiltration beyond the tumor through the vessels and the maximum distance from the tumor edge to the most distal site of infiltration was 4 mm. In conclusion, a 2 cm surgical margin, as recommended in Japanese surgical textbooks, is adequate for EGCs with reference to vascular invasion.

Humans↗

MRI of symptomatic sacral perineural cyst.

Sacral perineural cyst is a relatively rare condition. To our knowledge, reports of MR findings associated with sacral perineural cyst have been limited to only six cases. We present for the first time high field MR findings in a case of sacral perineural cyst. The cyst appeared as a cystic lesion in the sacral spinal canal and had intermediate signal intensity on T1W images and high signal intensity on T2*W images compared with CSF. Slight erosion remodeling of the sacrum was also seen anteriorly. Our case was symptomatic and present with radiculopathy (sciatic pain). Surgical treatment was done to result in dramatic improvement of the sciatic pain.

Cysts↗

Metastatic lung tumors and extended indications for surgery.

From 1973 to 1989, 110 thoracotomies for metastatic lung tumors were done on 85 patients, in our institution. The overall actuarial five-year survival rate was 31%. The five-year survival rate for carcinoma was 40% and for sarcoma was 11% (less than 0.05). A favorable outcome was obtained in the group with primary tumors of the breast, head-neck, and chorion. The outcome for patients with bone and soft tissue tumors was poor. The significant predictors of a better long-term survival for metastatic lung tumors were disease-free interval (DFI) greater than 12 months, tumor size less than or equal to 30 mm in diameter, and tumor doubling time (TDT) greater than 40 days (p less than 0.05). The number of nodules and the laterality of the sites of recurrence did not relate to survival time. Of 22 patients undergoing regional lymph node dissection, seven (32%) had positive nodes. Even in cases of a recurrent pulmonary metastasis, the three-year survival in those with multiple thoracotomies was 16%. We wish to draw attention to the finding that a prolonged survival time can be achieved for patients undergoing regional lymph node dissection or even repeated resections for a recurrent pulmonary metastases.

Adolescent↗

Combination of nifedipine and carteolol compared to nifedipine alone in diurnal blood pressure variation and exercise blood pressure in patients with essential hypertension.

A combination of nifedipine (40 mg twice daily) plus carteolol (10 mg twice daily) was compared with nifedipine monotherapy in ten patients with essential hypertension. Ambulatory blood pressure (BP) monitoring over 24 hours and treadmill exercise testing were performed before treatment with nifedipine (but after the placebo period), after four weeks of nifedipine treatment, and after four weeks of nifedipine+carteolol combination therapy. At the end of nifedipine monotherapy, 24-hour average ambulatory BP, minimum ambulatory BP during sleep, maximum ambulatory BP, and casual BP all decreased significantly (P less than 0.01). However, the standard deviation (SD) of the ambulatory BP was not affected. The change in systolic BP response to treadmill exercise increased. After a four-week period of nifedipine+carteolol combination therapy, average ambulatory BP and maximum ambulatory BP were further decreased (P less than 0.01). The SD of the ambulatory BP and the change in BP response to exercise were significantly decreased (P less than 0.01), but the minimum ambulatory BP was not affected. These findings suggest that nifedipine and carteolol differ in their influence on diurnal BP variation and on exercise-induced BP elevation. Carteolol may mainly attenuate stress-induced BP elevation and have little influence on nocturnal BP decline. In contrast, nifedipine may affect the BP profile uniformly over the entire day. Nifedipine+carteolol combination therapy may be superior to nifedipine monotherapy because carteolol has a minimal effect on nocturnal BP and decreases stress-induced BP elevation.

Blood Pressure↗

Pulmonary sequestration in older child and in adults.

Pulmonary sequestration is often found in children with recurrent pneumonia, but is not rare in adults. During the last 6 years (1985-1990), 6 patients with pulmonary sequestration were surgically treated. One 40-year-old patient had an extralobar sequestration, and 5 patients ranging in age from 14 to 26 years had an intralobar sequestration. The patient with extralobar sequestration was asymptomatic. In cases of intralobar sequestration, 4 patients were symptomatic. All 6 patients had an abnormal chest roentgenogram. Preoperative arteriography revealed anomalous blood supply came from a systemic artery in 4 patients. All cases with intralobar sequestration had a lower lobectomy, and one case with extralobar sequestration had an extirpation. Even in cases without any symptoms, there was the possibility of a microscopic infection in the sequestrated lesion with the occurrence of later symptoms. Therefore, patients diagnosed with pulmonary sequestration should be considered for surgical resection.

Adolescent↗

In vivo formation of codeinone and morphinone from codeine. Isolation and identification from guinea pig bile.

Codeinone (CO) and morphinone (MO) were isolated and identified in the bile of guinea pigs given sc injections of codeine. Authentic CO was synthesized and characterized by the NMR and mass spectra of its 2-mercaptoethanol (ME) adduct. This material was then used as the standard to identify the CO-ME adduct in the bile of codeine-treated animals. The MO-ME adduct was also identified in the bile with authentic materials prepared earlier. The results of our investigations indicated that 10.5 and 2.7% dose of CO and MO, respectively, were produced for 6 hr after the codeine was given. The metabolites were separated by preparative HPLC on a reverse phase column packed with C18 gel using a 10 mM sodium phosphate buffer, pH 6.8/CH3CN, 1:1 (v/v) as an eluate. For the further purification of metabolites, we used another reverse phase column with the same mobile phase. A structural elucidation of the ME adduct of metabolites was then performed by fast atom bombardment mass spectroscopy and 400 MHz fourier transform-NMR spectrometric analysis, and identified as (8S)-(2-hydroxyethylthio)dihydrocodeinone and (8S)-(2-hydroxyethylthio)dihydromorphinone, respectively.

Animals↗

Benign tumors and tumor-like lesions of the lung.

From 1974 to 1988, we experienced 36 benign tumors or tumor-like lesions of the lung out of 721 thoracotomies performed for the treatment of lung tumors. There were 21 hamartomas, nine inflammatory pseudotumors and six sclerosing hemangiomas. On average patients were in their fifth or sixth decade, which was somewhat younger than that for bronchogenic carcinoma. Marked female predominance was noted in the cases of sclerosing hemangioma. There were no particular characteristics with respect to symptoms or location of the tumors. Over 80% of the benign tumors were less than 30 mm in diameter. Diagnosis of the benign tumors was usually not difficult from the routine chest X-ray film. However, some cases produced shadows on X-ray films closely resembling those of lung cancer. Surgical removal preserving as much lung parenchyma as possible is indicated for definite diagnosis and treatment.

Adolescent↗

Degeneration of posterior column nucleus, inferior olivary nucleus and cerebellar cortex: system degeneration of paraneoplastic disease?

Degeneration of the posterior column nucleus, inferior olive, and cerebellar cortex is reported in a cancer patient. A 70-year-old man developed an ataxic gait and rapidly progressive disturbance of deep sensation over six months, followed by an abasic state. Early well-differentiated tubular adenocarcinoma was detected and total gastrectomy was performed. He died due to pulmonary tuberculosis about two years and nine months after the operation. Degeneration of the posterior column nuclei was found, explaining the disturbance of deep sensation noted in the clinical course, although there were few changes in the peripheral nerves, dorsal root ganglia, and spinal cord. Degeneration of the inferior olive and cerebellar corte was also found. Metastatic small cell carcinoma was present in the right pulmonary hilar and paratracheal lymph nodes at autopsy without any detectable primary focus. There was neither recurrence nor metastasis of the gastric carcinoma. This is the first case report of this type of central nervous system degeneration in a cancer patient, and its pathogenesis and etiology remain obscure. We discuss whether system degeneration or paraneoplastic degeneration was the etiology.

Adenocarcinoma↗

Chemosensitivity testing of human lung cancer tissues using the succinate dehydrogenase inhibition test.

We examined the chemosensitivity of 57 primary lung cancer specimens to 9 antitumor drugs, using the succinate dehydrogenase inhibition (SDI) test. Average succinate dehydrogenase (SD) activity was reduced to less than 50% by cis-diaminedichloroplatinum (II) (DDP), cyclophosphamide (CPA), carboquone (CQ), mitomycin C (MMC) and adriamycin (ADM). The lung cancer cells were relatively resistant to pepleomycin (PEP), 5-fluorouracil (5 FU), vincristine (VCR) and vindesine (VDS). Small cell lung cancers, or early stage lung cancers, tended to be more sensitive to these antitumor drugs. However, differences in sensitivity with respect to either histology, staging or degree of differentiation were not statistically significant. Correlation of SD activity between 2 drugs was high among those which inhibit DNA synthesis (DDP, CPA, CQ or MMC), or between VCR and VDS (inhibitor of mitosis), however, the correlation between VDS and CPA, CQ or DDP was weak. The SDI test is a simple in vitro method readily available to aid in selecting drugs to treat patients with lung cancer.

Adult↗

(8S)-(glutathion-S-yl)dihydromorphinone, a novel metabolite of morphine from guinea pig bile.

A novel glutathione-conjugated metabolite of morphine has been isolated from the bile of guinea pigs given morphine. The metabolite was separated by preparative HPLC on a reverse phase column (YMC-GEL C18) using methanol/water (1:4, v/v) as eluate and purified by HPLC on another reverse phase column (mu-Bondapak phenyl) using water/acetonitrile/trimethylamine/acetic acid (150:3:2:1, v/v) as a mobile phase. The unambiguous structure assignment of the metabolite was performed by fast atom bombardment mass spectrometry and 400 MHz fourier transform NMR spectrometric analysis, and it was identified as (8S)-glutathion-S-yl)dihydromorphinone, in comparison with the synthetic morphinone-glutathione adduct.

Animals↗

Regional lymph node metastases in well-differentiated thyroid carcinoma.

The status of regional lymph node metastases was assessed in 171 patients with thyroid cancer who underwent a variety of thyroidectomy procedures with regional lymph node dissection at Kanazawa University, from January 1979 to March 1986. The rates of regional lymph node metastasis in minimal and ordinary thyroid cancer were 57% and 84% respectively. Since the rates of lymph node metastasis were high not only in the central cervical compartment but also in the lateral jugular compartment, modified radical neck dissection in the ipsilateral neck is at least recommended in patients with these thyroid cancers. Furthermore, high frequencies of bilateral regional lymph node metastases were found in patients with obviously widespread involvement of the bilateral lobes, with cancer located in the isthmus, with clinically detectable bilateral or contralateral jugular lymph node metastases and with histological involvement in the contralateral paratracheal lymph nodes. Bilateral modified radical neck dissection is recommended in these patients.

Adenocarcinoma↗