Search PubMed⌕ Search

Biomedical subjects

T Nakano

Publications and source records attributed to T Nakano.

At least 343 records · Page 19Linked to original sources
PubMed1999

Prognosis of completely asymptomatic adult patients with hypertrophic cardiomyopathy.

OBJECTIVES: We investigated the long-term prognosis of completely asymptomatic adult patients with hypertrophic cardiomyopathy (HC). Diagnosis of HC was suspected because of an abnormal electrocardiogram and/or cardiac murmur and confirmed by echocardiography and/or left ventricular angiography, and hemodynamic investigation. BACKGROUND: Hypertrophic cardiomyopathy shows marked heterogeneity in clinical expression and prognosis. The prognosis of asymptomatic patients with HC has not been fully defined. METHODS: Of 128 consecutive adult patients with HC, 58 asymptomatic patients (Group 1, mean age 42.8 years) and 70 symptomatic patients (Group 2, mean age 50.4 years) were studied to assess cardiac mortality. Mean follow-up periods were 11.0 years for Group 1 and 9.1 years for Group 2. RESULTS: At presentation, Group 1 patients were younger and had smaller left atrial dimensions than did Group 2 patients. The annual cardiac mortality rate and the rate for sudden death alone in Group 1 were significantly lower than in Group 2 (0.9% vs. 1.9%, p < 0.05, 0.1% vs. 1.4%, p < 0.05, respectively). Although about one-third of the survivors in Group 1 had cardiac symptoms at their most recent evaluation, only one patient died suddenly compared with eight in Group 2. The annual mortality rate due to heart failure was similar in each group. Only a syncopal episode was associated with both cardiac death and sudden death for both groups combined. CONCLUSIONS: The cardiac mortality rate for completely asymptomatic adult patients with HC was very low, significantly lower than that of symptomatic patients, and there was a disproportionately low incidence of sudden death.

Adult↗
PubMed1999

Effects of the phosphorylation of myosin phosphatase by cyclic GMP-dependent protein kinase.

Cyclic GMP-dependent protein kinase (PKG) phosphorylated, in vitro, the large (MYPT1) and small (M20) regulatory subunits of myosin phosphatase (MP) with maximum stoichiometries of 1.8 and 0.6 mol of phosphate/mol subunit, respectively. The phosphorylation of these subunits by PKG did not affect the phosphatase activity towards the 20 kDa myosin light chain. However, phosphorylation of the MP holoenzyme decreased the binding of MP to phospholipid. The phosphorylation of the serine residue of the C-terminal part of MYPT1 was crucial for these interactions. These results suggest that the phosphorylation of MP by PKG is not a direct mechanism in activating MP activity, and that other indirect mechanisms, including the interaction between MP and phospholipids, might be candidates for Ca2+ desensitization via cGMP in smooth muscle.

Animals↗
PubMed1999

Immunohistochemical investigation of new suppressor oncogene p130 in oral squamous cell carcinoma.

New onco-suppressor gene p130 is one of the Rb family forms and is reported to undergo allelic loss in hepatocellular, prostate, and breast carcinomas; however, no report of p130 has been made in oral tumors. The present study dealt with the expression of p130 and Rb proteins by immunohistochemical staining in oral squamous cell carcinomas (n = 110) and oral mucosa. The site of the carcinomas included tongue (n = 48), gingiva (n = 32), oral floor of the mouth (n = 15), oropharynx (n = 6), buccal mucosa (n = 5), and others (n = 4). Histologically there were 65 well-differentiated carcinomas, 33 moderately differentiated carcinomas, and 12 poorly differentiated ones. Positive staining for p130 and Rb was localized to suprabasal cell layers of the normal oral epithelium. In the oral squamous cell carcinoma, positive staining for p130 and Rb was observed in well-differentiated carcinomas (p130, 66.2%; Rb, 78.5%), more than in poorly differentiated ones (p130, 16.7%; Rb, 50.0%). In immunoelectron microscopic features, p130 protein was localized in the nucleus and mitochondria. The expression of p130 was related to the degree of tumor differentiation as that of Rb. It is suggested that p130 gene may be associated with the development of a wide variety of human malignancies rather than the progression.

Adult↗
PubMed1999

Cloning and characterization of ethanol-regulated esterase genes in Acetobacter pasteurianus.

The esterase encoding genes, est1 and est2, were cloned from Acetobacter pasteurianus. Nucleotide sequence analysis of est1 revealed a gene of 954 bp, and est1 coded for an arylesterase with a molecular weight of 34863 Da consisting of 317 amino acids. The est2 gene contained an open reading frame composed of 1221 bp encoding an esterase with a molecular weight of 43389 Da consisting of 406 amino acids. The est1 gene showed some similarity, but the est2 gene showed no significant homology to other esterases reported in various microorganisms. Northern blot analysis of total RNA from A. pasteurianus revealed that transcription of the est1 gene was induced only when the cells were grown in a medium containing ethanol, and suggested that the est1 transcript is monocistronic. In contrast, transcription of the est2 gene was repressed in the presence of ethanol. In the absence of ethanol, expression of the est2-mRNA, capable of encoding a multiple number of proteins, was revealed by Northern blot analysis. In addition, deletion analysis indicated that the 5'-region of the est2 gene contained a cis-acting domain for est2 transcriptional regulation. Analysis of the est1 promoter using the chloramphenicol acetyltransferase gene as a reporter gene showed that the promoter within the 305-bp fragment upstream of the ATG initiation codon was responsible for the transcription in cells grown in the presence of ethanol. Primer extension analysis of est1-mRNA showed that the transcription initiation site was 49 bp upstream from the ATG initiation codon. The results of a gel mobility shift assay indicated that there is a regulatory protein related to est1 regulation, which may have some relation to the ethanol resistance of Acetobacter sp.

Journal Article↗
PubMed1999

Determination of sialic acid by the thiobarbituric acid reaction in sweet whey and its fractions.

Determination of sialic acid in sweet whey is useful as the concentration of sialic acid reflects the amount of glycomacropeptide (GMP) present. In this study, the concentration of total sialic acid was determined by the thiobarbituric acid reaction after dialysis of samples in water, and the concentration of GMP sialic acid was estimated by gel chromatography on Sephacryl S-200. Concentrations of total and GMP sialic acid determined in a sweet whey sample prepared from fresh milk were 2.0 and 1.5 microg/mg of dry weight, respectively. Analysis of commercial samples showed that the concentration of total sialic acid in sweet whey was 9 times lower than that in whey protein concentrate but 18 times higher than that in whey permeate. A similar trend was observed in the variation of GMP sialic acid concentration between sweet whey and why protein concentrate. The concentration of sialic acid differed 10 times between two samples of whey protein isolate.

Chromatography, Gel↗
PubMed1999

Suppression of agglomeration in fluidized bed coating. III. Hofmeister series in suppression of particle agglomeration.

PURPOSE: Fourteen kinds of salts consisting of various cations and anions in the Hofmeister series were used as additives for suppression of particle agglomeration in the fluidized bed coating. We attempted to clarify the relationship between the suppression effect of the salts and the Hofmeister series of their consistent ions. METHODS: Fluidized bed coating was carried out with hydroxypropylmethyl cellulose (HPMC) aqueous coating solution containing the salts and Celphere as core particles. To elucidate the salting-out power of the salts for HPMC, the transmittance of the coating solutions at 600 nm was measured at various temperatures and the phase separation temperature (T(PS)) was determined from the values at 50% transmittance. RESULTS: A high suppression effect was observed when the salts including high order ions in the Hofmeister series were added to the coating solution. T(PS) decreased in the presence of the salts except for sodium iodide and sodium thiocyanate and lowered with the higher order ion in the Hofmeister series. The particle agglomeration was suppressed with decrease in T(PS) of the HPMC aqueous coating solution. CONCLUSIONS: It has been suggested that the suppression effect of a salt on the particle agglomeration depended on the salting-out power of the salt. We regard sodium citrate and potassium citrate as very useful pharmaceutical additives for the suppression of particle agglomeration in actual pharmaceutical coating.

Algorithms↗
PubMed1999

Bright light treatment for sleep-wake disturbances in aged individuals with dementia.

Treatment using bright light exposure was carried out on six aged subjects with dementia in two nursing homes. Sleep logs were recorded by the staff. Bright light treatment was applied in the late morning every day. The %sleep in the lights-out period and/or the %wake in daytime increased in three subjects. In the other three subjects, sleep onset time was advanced. In all subjects abnormal behavior episodes around the lights-out time tended to be reduced. These results suggest that bright light treatment is effective in improving the sleep-wake disturbances of aged individuals with dementia.

Aged↗
PubMed1999

Effects of moderately bright light on subjective evaluations in healthy elderly women.

Eight healthy elderly women aged 56-72 years (mean age: 67.4 years) participated in this study. They were exposed to moderately bright light (1000 lux) for 1h in the morning every 6 days in their homes. Moderately bright light improved self evaluations for alertness, mood, motivation, happiness, refreshment, concentration and appetite after the second exposure to the light. Sleep maintenance, anxiety and integrated sleep feeling also improved after the fourth exposure to the light. The phase of rectal temperature rhythm did not change in a moderately bright light condition. These results suggest that bright light influences sleep quality and self evaluations without changing the biological rhythm phase.

Adaptation, Psychological↗
PubMed1999

Suicidal thoughts in cancer patients: clinical experience in psycho-oncology.

Because cancer is a life-threatening illness, its impact on the patient's emotional well-being, such as suicidal thoughts, has become a significant problem in public health as well as in clinical oncology. Factors such as the pain and hopelessness are suggested as making cancer patients more vulnerable to suicide. On the other hand, euthanasia and physician-assisted suicide are now important medical and social issues all over the world. However, little is known about the relationship between the characteristics of cancer patients and suicidal thoughts. The present study investigated the characteristics of patients who were referred to the Psychiatry Division, National Cancer Center Hospital East, due to risk of suicide or suicide attempts. Fourteen patients were referred, representing 3.9% of all consultations. Most of these patients suffered from advanced cancer and poor physical functioning. The most frequent psychiatric diagnosis was mood disorder (57%), and the next was delirium (29%). In patients with mood disorders (8 cases), suicidal thoughts disappeared after psychiatric treatment in 5 cases, but not in 3 cases. Those three patients survived a significantly shorter time than the others after psychiatric consultation. These empirical data might indicate that most suicidal thoughts experienced by cancer patients are not rational, and a careful evaluation, including psychiatric assessment, should be conducted in such patients.

Aged↗
PubMed1999

An autopsy case of a malignant pericardial mesothelioma in a Japanese young man.

An autopsy case of a malignant pericardial mesothelioma in a 27-year-old man with no history of exposure to asbestos is reported. He was admitted for heart failure due to pericardial effusion of unknown origin and surgically drained, but later died. The diagnosis of a malignant pericardial mesothelioma was made on the basis of histologic, immunohistochemical and ultrastructural findings. The tumor was located on the pericardium, but autopsy revealed that it had spread extensively in the mediastinum and the lungs. Microscopically, the tumor cells were epithelial like and contained histochemically demonstrable glycogen and hyaluronic acid. Immunohistochemical studies of the tumor demonstrated positive immunoreactivity for cytokeratin 19, muscle actin HHF35, epithelial membrane antigen, CA125, p53 and p21WAF1/CIP1 whereas the tumor was negative for cytokeratins 10 and 17, carcinoembryonic antigen, vimentin, epithelial antigen BerEP4, S-100, c-erbB2 and bcl-2. A high MIB-1 labeling index was noted. Under the electron microscope the tumor cells exhibited long, thin villi. The operation and autopsy findings thus revealed this to be a very rare case of malignant pericardial mesothelioma in a young man.

Adult↗
PubMed1999

Measurements of the equivalent whole-body dose during radiation therapy by cytogenetic methods.

Estimates of equivalent whole-body dose following partial body exposure can be performed using different biophysical models. Calculations should be compared with biodosimetry data, but measurements are complicated by mitotic selection induced in target cells after localized irradiation. In this paper we measured chromosomal aberrations in peripheral blood lymphocytes during radiotherapy, and estimated the equivalent whole-body dose absorbed, by using the novel technique of interphase chromosome painting. Premature chromosome condensation was induced in stimulated lymphocytes by incubation in calyculin A, and slides were hybridized in situ with whole-chromosome DNA probes specific for human chromosomes 2 and 4. Reciprocal exchanges were used to estimate the equivalent whole-body dose, based on individual pre-treatment in vitro calibration curves. Equivalent whole-body dose increased as a function of the number of fractions, and reached a plateau at high fraction numbers. Chromosomal aberration yields were dependent on field size, tumour position and concurrent chemotherapy. Results suggest that interphase chromosome painting is a simple technique able to give a reliable estimate of the equivalent whole-body dose absorbed during therapeutic partial-body irradiation.

Aged↗
PubMed1999

Screening for nicotine dependence among smoking-related cancer patients.

To identify lung and head-and-neck cancer patients who will have difficulty stopping smoking it is necessary to measure the severity of their nicotine dependence. In this study, we compiled a Japanese version of the Fagerstrom test for nicotine dependence (FTND) and examined its reliability and validity. One hundred and fifty-one cancer patients participated in this study and took our Japanese version of the FTND. Socio-demographic and medical data and information about smoking habits were obtained from a semi-structured interview, and the patients' nicotine dependence was evaluated according to the Diagnostic and Statistical Manual of Mental Disorders, 3rd Ed., Rev. (DSM-III-R). The mean FTND scores+/-SD of the group with nicotine dependence and the group without nicotine dependence were 6.85+/-2.00 and 3.70+/-2.13 respectively, and the difference was significant (P<0.001, Mann-Whitney's U-test). The test-retest correlation was 0.75. Cronbach's alpha of the FTND was 0.66. The FTND score correlated significantly with the number of satisfied criteria of nicotine dependence (r=0.70; P<0.001, Pearson's correlation). By using a receiver-operating-characteristic curve, we determined a score of 5/6 as a suitable cut-off point for nicotine dependence; this point gave high sensitivity and specificity (0.75 and 0.80, respectively). These results suggest that our Japanese version of FTND is a reliable and valid measure of nicotine dependence in patients with smoking-related cancers.

Adult↗
PubMed1999

Hypertrophic cardiomyopathy: MR measurement of coronary blood flow and vasodilator flow reserve in patients and healthy subjects.

PURPOSE: To evaluate coronary blood flow per gram of myocardial mass and vasodilator flow reserve in patients with hypertrophic cardiomyopathy (HCM) and in healthy subjects by using breath-hold velocity-encoded cine (VEC) magnetic resonance (MR) imaging. MATERIALS AND METHODS: Twenty-nine patients with HCM and nine healthy volunteers were examined. Fast VEC MR images were obtained in an oblique imaging plane perpendicular to the coronary sinus before and after intravenous injection of dipyridamole (0.56 mg/kg). The products of mean velocity and cross-sectional area of the vessel were integrated to measure blood flow. Breath-hold cine MR images encompassing the entire left ventricle were acquired to quantify the left ventricular mass. RESULTS: In the basal state, the coronary blood flow per gram of myocardial mass was 0.74 mL/min/g +/- 0.23 in healthy subjects and 0.62 mL/min/g +/- 0.27 in patients with HCM. After administration of dipyridamole, coronary blood flow in patients with HCM increased to a level significantly less than that in healthy subjects (1.03 mL/min/g +/- 0.40 vs 2.14 mL/min/g +/- 0.51; P < .01), resulting in a severely depressed flow reserve ratio in patients with HCM compared with that in healthy subjects (1.72 +/- 0.49 vs 3.01 +/- 0.75; P < .01). CONCLUSION: Breath-hold VEC MR imaging is a noninvasive technique for evaluating coronary flow per gram of myocardial mass and coronary flow reserve.

Blood Flow Velocity↗
PubMed1999

Trousseau's syndrome with brachiocephalic vein thrombosis in a patient with uterine carcinosarcoma. A case report.

The authors treated a patient with the previously unreported occurrence of brachiocephalic vein and superior vena cava thrombosis in association with a distantly located cancer. A 71-year-old woman presented with swelling over the right side of the neck and abdominal distension. Physical examination revealed a huge mass, and computed tomography demonstrated thrombosis of the brachiocephalic vein and superior vena cava accompanied by jugular vein dilatation. No coagulation disorder was demonstrable. After anticoagulation and thrombolysis, hysterectomy was performed; microscopic examination of the specimen revealed uterine carcinosarcoma. Even though local tumor obstruction is a much more common cause of neck vein thrombosis, a distant occult cancer can present as this form of Trousseau's syndrome. In patients with otherwise unexplained neck vein thrombosis, examination not only of the head and neck but also of the abdomen and pelvis should be pursued.

Aged↗
PubMed1999

Reduced growth hormone receptor messenger ribonucleic acid in an aged man with chronic malnutrition and growth hormone resistance.

A severely malnourished 87-yr-old man presented with hypoglycemia. Serum GH levels were elevated, and serum levels of insulin-like growth factor I (IGF-I), IGF-binding protein-3, and GH-binding protein were extremely reduced. The patient's GH was biologically active. Administration of GH for 4 consecutive days resulted in a slight increment in serum IGF-I levels, but no elevation of serum IGF-binding protein-3. The expression of GH receptor messenger ribonucleic acid in the liver was greatly reduced. An autopsy revealed a Rathke's cleft cyst confined to the sella turcica. Immunohistochemical studies for GH showed that there was nothing to suggest a tumor overproducing GH. In addition, TSH levels were elevated in the presence of normal thyroid hormone levels, and there was a cluster of cells showing strong immunohistochemical staining for the TSH beta-subunit in the pituitary. In this patient, the decreased expression of GH receptor messenger ribonucleic acid in the liver may have been responsible for the GH resistance, which was probably caused by malnutrition.

Aged↗
PubMed1999

Nuclear localization of gold labeled-hydrocortisone-bovine serum albumin conjugate injected intravenously into the hormone-target cells of rat.

We have suggested in a previous study using 2-nm colloidal gold labeled-testosterone-bovine serum albumin (testosterone-BSA-gold) that 2-nm gold labeled-steroid hormone-BSA conjugates would be a useful tool for analyzing the mechanism of steroid hormone action (39). In this study, we examined whether hydrocortisone-BSA conjugate (hydrocortisone-BSA) showed a similar distribution to radiolabeled hydrocortisone in vivo, by injecting 2-nm colloidal gold labeled-hydrocortisone-BSA (hydrocortisone-BSA-gold) into the rat tail vein. The hydrocortisone-BSA-gold with silver enhancement became visible as silver deposits under electron microscopy in the nuclei of hepatocytes and hepatic stellate cells but not in Kupffer cells in the liver, and in the thymocytes and thymic reticuloepithelial cells in the thymus of a rat killed 2 h postinjection. The percentage of nuclei showing deposits in the non-target cells, the epithelial cells of the seminal vesicle, was similar to the value in the seminal vesicle of a control rat injected with BSA labeled with 2-nm colloidal gold as reported previously. In the hepatocytes and thymocytes of a control rat not injected, the percentages of nuclei showing deposits were similar to those in the rat injected with testosterone-BSA-gold or BSA-gold as reported previously, but lower than those in the rat injected with hydrocortisone-BSA-gold. These results suggest that hydrocortisone-BSA-gold is useful for the morphological study of hydrocortisone target cells, and imply that BSA conjugated with hydrocortisone can enter the target cell nuclei of the rat. The present study further indicates that the fate of gold labeled-steroid hormone-BSA conjugates may be decided at the cell membrane level.

Animals↗
PubMed1999

Right ventricular diastolic function in patients with hypertrophic cardiomyopathy--an invasive study.

To assess diastolic function of the right ventricle (RV) in patients with hypertrophic cardiomyopathy (HCM), biplane RV angiograms and RV pressures were analyzed in 19 HCM patients and in 13 normal subjects. RV and left ventricle (LV) pressures were measured using catheter-tip manometers. RV volumes were obtained from frame-by-frame tracings of angiograms. Ventricular relaxation was assessed by the time constant of isovolumic pressure decay (T). The peak filling rate (PFR) and the time to PFR (TPFR) were used as parameters of early diastolic filling, and the right atrial contribution to RV filling (%AF) was used as a parameter of late diastolic filling. The T for the RV was significantly prolonged in HCM patients. However, there was no significant correlation between the T for the RV and LV, nor did the T for the RV correlate with the RV ejection fraction or interventricular septal wall thickness. The TPFR, but not PFR, was significantly greater in HCM patients, and the %AF tended to be increased in HCM, but not significantly. The RV diastolic pressure-volume relations in the HCM patients shifted upward. In conclusion, impaired isovolumic relaxation and delayed diastolic filling and decreased diastolic distensibility are present in the RV of HCM patients.

Adult↗