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T Nakada

Publications and source records attributed to T Nakada.

At least 109 records · Page 6Linked to original sources
PubMed1998

'Musical brain' revealed by high-field (3 Tesla) functional MRI.

The cortical areas subserving music literacy were investigated using high-field (3 Tesla) functional magnetic resonance imaging (fMRI). The activation pattern associated specifically with music score reading was compared with that associated with reading text in a subject's primary and secondary language. While the areas of activation were predominantly identical for all three reading modalities, there were areas within the occipital cortex activated exclusively by music score reading. Grand analysis of the activation patterns of eight pianists unequivocally identified that the principal cortical area needed for music literacy is the cortex flanking the right transverse occipital sulcus (musical brain).

Adult↗
PubMed1998

Elevated levels of telomerase activity in malignant pheochromocytoma.

BACKGROUND: Although malignant pheochromocytoma is a life-threatening illness, there is no excretory profile that is predictive of malignancy. Reliable prediction of malignant behavior on the basis of histopathology is also notoriously difficult. Although DNA ploidy can be a helpful indicator, aneuploidy per se is not considered to be a specific marker of malignancy. Mutations in p53 have been reported to occur frequently in cases of benign pheochromocytoma. Thus, molecular analysis of this protein is not a useful diagnostic tool. The authors analyzed telomerase activity in benign and malignant pheochromocytomas and assessed its utility as a prognostic marker. METHODS: Telomerase activity was estimated in 16 benign pheochromocytomas, 3 malignant pheochromocytomas, and 16 normal adrenal medullae by the fluorescence-based telomeric repeat amplification protocol. The telomerase activities of each group of samples were compared. RESULTS: No telomerase activity was detected in any of the normal adrenal medullae or the benign pheochromocytomas. By contrast, all of the three malignant pheochromocytomas had elevated telomerase activity. The telomerase activity in each tumor was determined to be 87.6 units, 71.2 units, and 180.3 units, respectively. CONCLUSIONS: The expression of telomerase activity in pheochromocytoma clearly suggests the malignant behavior of the component cells. Analysis of telomerase activity appears to be a powerful tool for the diagnosis of malignant pheochromocytoma.

Adrenal Gland Neoplasms↗
PubMed1998

Successful removal of large adrenal pheochromocytoma on the right side with liver mobilization.

We report a case of a large adrenal pheochromocytoma on the right side successfully removed with liver mobilization. Bilateral anterior subcostal incision with a ventral midline incision extending from the xiphoid and subsequent use of self-retraction system provided satisfactory exposure of liver and diaphragm. This incision is useful for easy mobilization of the liver and manipulation of the inferior caval vein in patients with large adrenal tumour on the right side.

3-Iodobenzylguanidine↗
PubMed1998

Renal cell carcinoma with renal artery aneurysm.

We describe a patient who was diagnosed as renal cell carcinoma with renal artery aneurysm in the contralateral kidney. Right aneurysmectomy followed by simple arteriorrhaphy with termino-lateral anastomosis, and then left radical nephrectomy were performed in one session. The patient did well postoperatively. Generally, surgical indication of renal artery aneurysm itself has been yet a matter of debate. In such case like this, however, it seems better to resect any kind of aneurysm of the opposite side, taken into consideration the haemodynamic changes after nephrectomy. Surgical indications are commented on.

Aneurysm↗
PubMed1998

Serum level of carboxyterminal propeptide of type I procollagen in haemodialysis patients.

Serum concentrations of carboxyterminal propeptide of type I procollagen (PICP) and carboxyterminal parathyroid hormone (C-PTH) were measured in 33 haemodialysis patients. Serum levels of PICP and C-PTH in the haemodialysis group were significantly higher than those in the controls. Although there was no correlation between serum C-PTH and creatinine, a positive correlation was found between PICP and creatinine. This indicates that the measurement of PICP in serum is useful for monitoring metabolic bone diseases in haemodialysis patients.

Adult↗
PubMed1998

Endocrinological and pathological entities of the pre-Cushing's syndrome.

The purpose of the study was to clarify the disease entity of pre-Cushing's syndrome. The authors report on the pathological findings and contents of various steroids in the adenomas of three cases of pre-Cushing's syndrome. Oncocytes were found in one adenoma and others were pure clear cell dominant adenomas. All the adenomas contained higher concentrations of precursor steroids than those of five cases of Cushing's syndrome. However, the patterns of increased precursors were quite different among the three cases. Pre-Cushing's syndrome appeared to include several different kinds of disease entities.

Adrenal Cortex↗
PubMed1998

Bladder cancer in a patient on long-term haemodialysis.

We report a case of bladder cancer on long-term haemodialysis. The relationship between bladder cancer and haemodialysis, and the necessity of periodic cytology of bladder washing are discussed.

Carcinoma, Transitional Cell↗
PubMed1998

Successful chemotherapy in a patient with recurrent carcinoma of the urachus.

Urachal neoplasm generally has a poor prognosis, because of long latency period, extravesical progression and pathological predominant pattern of adenocarcinomas. We report a case of recurrent poorly differentiated carcinoma of urachal remnant, which responded well to combination systemic chemotherapy (methotrexate, vinblastine, doxorubicin and cisplatin: M-VAC). Our case was possibly of transitional cell origin. The patient has been symptom-free even 13 months after the first chemotherapy course.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

The effect of triathlon on urinary excretion of enzymes and proteins.

In order to investigate the effect of triathlon and renal function of normal subjects, we evaluated the excretion of urinary enzymes and proteins before and after triathlon. From 6 subjects samples were obtained 24 hours after the first urine collection. We performed quantification of urinary total protein, beta2-microglobulin (beta2-M), N-acetyl-beta-D-glucosaminidase activity (NAG), and concentration of urinary creatinine from each participant. There was a significant increase in urinary total protein excretion immediately after triathlon (p<0.01). The urinary beta2-M and NAG excretions after triathlon were higher than the initial values. Post-exercise proteinuria in one subject persisted until the next morning, whereas the increased excretion of urinary beta2-M and NAG returned to the pre-exercise level at least 24 hours after triathlon. It appears to be reasonable to presume that glomerular damage may persist in some subjects who do heavy exercise.

Acetylglucosaminidase↗
PubMed1998

Schwannoma of the penis: report of a case and review of the literature.

A case of schwannoma located in the penile shaft in a 65-year-old male is described. Special stain using S-100 immunoperoxidase was useful in establishing the diagnosis in this case. We reviewed the literature on penile schwannoma and focussed on the diagnosis of this rare ailment.

Aged↗
PubMed1998

Pericentric inversion of chromosome 9 in infertile men.

Reproductive condition was studied in 6 infertile men with pericentric inversion of chromosome 9. Semen analyses revealed one azoospermia, one oligozoospermia, three asthenozoospermias and one normozoospermia. Four cases showed normal levels of plasma gonadotropins and testosterone. The response of plasma testosterone to human chorionic gonadotropin was within the normal range in all cases. However, the administration of LH-RH resulted in abnormal response of plasma gonadotropin in all patients. These results indicate that infertile males with pericentric inversion of chromosome 9 have an abnormality in the hypothalamic-pituitary-testicular axis.

Adult↗
PubMed1998

Pulmonary function after posterior retroperitoneoscopic surgery.

Pulmonary function tests were performed in 12 patients who underwent posterior retroperitoneoscopic surgery, before and on the 3rd and 7th days after operation. Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FCV, vital capacity (VC), total lung capacity (TLC), residual volume (RV) and functional residual capacity (FRC) were not significantly different between before and after surgery. It is assumed that posterior retroperitoneoscopic surgery could be performed without impairment of pulmonary function after surgery.

Adrenalectomy↗
PubMed1998

Influence of luteinizing hormone-releasing hormone analogues on serum levels of prostatic acid phosphatase and prostatic specific antigen in patients with metastatic carcinoma of the prostate.

Serum concentrations of luteinizing hormone (LH), testosterone, prostatic acid phosphatase (PAP) and prostatic specific antigen (PSA) were measured in 16 patients with advanced prostatic cancer before and after treatment with luteinizing hormone-releasing hormone (LHRH) analogue. An initial rise of serum LH and testosterone levels was observed on day 2 of the treatment. Subsequently, serum concentrations of PAP and PSA showed a transient increase on day 5 of the treatment. This indicates that LHRH analogues had better be given in combination with antiandrogens in patients with metastatic carcinoma of the prostate.

Acid Phosphatase↗
PubMed1998

Assessment of testicular function in experimental varicocele rats by phosphorus-31 magnetic resonance spectroscopy.

To assess testicular function in experimental varicocele rats, we used 31P magnetic resonance (MR) spectroscopy and compared MR spectroscopic parameters with flow cytometric DNA analysis. In vivo 31P MR spectroscopy and flow cytometric DNA analysis of testes were performed in 10 sham-operated and 9 induced varicocele rats. Although the testicular phosphomonoester (PM)/ATP ratio did not differ between sham-operated and induced varicocele rats, the phosphodiester (PD)/ATP ratio was significantly reduced and the inorganic phosphate (Pi)/ATP ratio was significantly increased in induced varicocele rats. There was no difference between the right and left sides. DNA flow cytometry showed a decrease in the percentage of haploid cells in induced varicocele rats, regardless of the side. This study indicates that in vivo 31P MR spectroscopy provides valuable information for assessment of testicular function.

Animals↗
PubMed1998

Hepatocyte growth factor stimulates DNA synthesis in rat preneoplastic hepatocytes but not in liver carcinoma cells.

BACKGROUND & AIMS: It is not well clarified whether hepatocyte growth factor (HGF) stimulates the growth of preneoplastic hepatocytes and liver carcinoma cells in vivo. The effect of HGF on in vivo DNA synthesis in these cells and also its effect on tyrosine phosphorylation of the HGF receptor protein (c-Met) in liver carcinoma were examined. METHODS: Lesions were induced in rats using 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB). The rats were given intravenous recombinant human HGF or vehicle, and DNA synthesis was assessed by the 5-bromo-2'-deoxyuridine labeling index. Tyrosine phosphorylation of c-Met by HGF was analyzed by Western blot. RESULTS: The labeling indices were significantly higher in the HGF group than in the vehicle control group in altered foci and hyperplastic nodules (preneoplastic hepatic lesions). No significant differences in the labeling indices were observed between the two groups with carcinoma. Tyrosine phosphorylation of c-Met in carcinoma cells was unaffected by HGF administration. CONCLUSIONS: HGF promotes the growth of preneoplastic hepatocytes but does not affect the growth of liver carcinoma cells in 3'-Me-DAB-treated rats.

Animals↗
PubMed1998

High-field (3.0 T) functional MRI sequential epoch analysis: an example for motion control analysis.

The widely accepted method of blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI) is a subtractive approach of state related analysis based on pictorial statistics, analogous to its predecessor, H2O(15) positron emission tomography (H2O(15)-PET). Although BOLD-fMRI has been shown to have several definite advantages over H2O(15)-PET, it has also been found to be much more artifact prone. This is primarily due to pixel misalignment of raw image data. Furthermore, similar to H2O(15)-PET, conventional means for pictorial analysis in BOLD-fMRI tends to be limited by the relatively low specificity of the observed activation. To overcome this limitation, we investigated a technique for BOLD-fMRI, sequential epoch analysis (SEA), on a high-field (3.0 T) system. The method allows for experimental designs comparable to neurophysiological techniques in primates and enables determination of activation of a selected cerebral cortical region of interest corresponding to a specific task. Utilizing SEA, we successfully identified a specific area within the premotor cortex which is activated complementary to the contralateral hand motion. The findings have strong implications regarding the neurological substrate responsible for the well described clinical phenomenon of physiological mirror movements in infants. The current study validated SEA BOLD-fMRI on a high-field system as a complementary method in the pictorial analysis of conventional fMRI, effectively offsetting the inherent problems of the conventional method, principally pixel misalignment and the relatively low specificity of the observed activation.

Adolescent↗