Biomedical subjects

M Tanno

Publications and source records attributed to M Tanno.

At least 37 records · Page 2Linked to original sources

PubMed1996

Comparative study of bone mineral density estimated by various methods of single- and dual-energy quantitative computed tomography: the capability of the four-equation four-unknown method.

A dual-energy (DE) quantitative computed tomography (QCT) method, the four-equation four-unknown method (DEQCT 4E-4U), was assessed and compared to single-energy (SE) QCT and standard DEQCT (two-line method). The results of this study indicate that bone mineral density (BMD) was more accurately estimated by the present method than by the SEQCT or standard DEQCT techniques on the basis of a phantom study when a large fat content was present. The results of both the phantom study and a human study also showed that the present method corrected for fat in estimating BMD in the presence of high-fat content. These findings suggest that use of this method for estimating BMD can provide useful information in studies assessing the metabolic state of bone. We propose that CT numbers estimated from excised vertebral bone marrow can serve as a soft-tissue correction for the present method.

Adult↗

PubMed1996

Myocardial viability in cases with persistent perfusion defects on the dipyridamole thallium-201 scintigram. A comparative study with autopsy findings.

The aim of this study was to assess the incidence of myocardial infarction among persistent perfusion defects in dipyridamole-stress thallium scintigraphy by inspecting autopsied hearts and to evaluate whether the regional thallium activity of a scintigraphic defect can predict the presence of infarction. Autopsied hearts were compared with dipyridamole myocardial scintigrams undertaken during life in 27 patients (mean age 85 +/- 8 years). The time interval from stress testing until death was 428 +/- 351 days. Regional thallium uptake of delayed perfusion defect was calculated on the short axis images. The grade of regional myocardial fibrosis in autopsy specimens was also quantified to correlate with the corresponding regional thallium uptake. In 6 of 15 (40%) regions with persistent defects on the scintigram, myocardial infarction was not found at autopsy. Regional thallium-201 uptake of delayed defects < 50% diagnosed infarction with a sensitivity of 82% and a specificity of 80%. A linear correlation (r = -0.67) was observed between percent thallium-201 uptake and the degree of myocardial fibrosis. In conclusion, perfusion defects at 4-hour imaging in dipyridamole-stress testing may overestimate the presence of myocardial infarction and regional thallium-201 activity is helpful in distinguishing between defects with and without infarction.

Aged↗

PubMed1995

Stimulation of DNA polymerase gamma activity by proliferating cell nuclear antigen.

DNA polymerase was partially purified from mitochondrial extracts of rat liver by phosphocellulose, DEAE-cellulose, heparin-Sepharose CL-6B and DNA-agarose column chromatography. By these purification steps, DNA polymerase and proliferating cell nuclear antigen (PCNA) were completely separated at the step of heparin-Sepharose CL-6B column chromatography. The isolated DNA polymerase was inhibited by ddTTP, but not by aphidicolin. The enzyme sedimented at about 8 S on 5-20% analytical sucrose density gradient centrifugation. These data showed that the DNA polymerase isolated from mitochondria is gamma in type. After the separation of DNA polymerase gamma and PCNA, the two fractions were remixed and DNA polymerase gamma activity was measured. DNA polymerase gamma activity was stimulated about three-fold or more in the presence of the PCNA fraction. This stimulation was inhibited by the addition of anti-PCNA rabbit IgG2a. In addition, highly purified human recombinant PCNA stimulated the DNA polymerase gamma activity. These results indicate that DNA polymerase gamma, like DNA polymerase delta, is activated by PCNA.

Animals↗

PubMed1995

Juvenile hyaline fibromatosis. Case report with five years' follow-up.

Juvenile hyaline fibromatosis (JHF) is a rare hereditary disorder named by Drescher et al. in 1969. As recently as 1985, only 30 cases had been reported worldwide. We report the case of a 9-year-old girl who was diagnosed with JHF at age 3 and has been closely followed since. She initially had slowly growing multiple soft tumors over her entire body as well as hypertrophic gingiva and mild bone deformities. She was originally misdiagnosed with infantile myofibromatosis at age 3. However, at age 6, because of the light and electron microscopic findings of the tumors, she was diagnosed as having JHF. Currently, at age 9, she has nodular lesions developing over her body as well as bone changes that are progressing with no evidence of regression.

Child↗

PubMed1995

Magnetic resonance imaging study of the brain in aged volunteers: T2 high intensity lesions and higher order cortical function.

The aims of the present study were to clarify the findings of magnetic resonance imaging (MRI) in the aging brain, and to relate the MRI findings to higher order cortical function. A total of 118 healthy aged volunteers (41 men, 77 women) underwent cranial MRI electroencephalography (EEG), Benton visual retention test (BVRT) and interview. The subjects had no past history or clinical evidence of cerebrovascular disorder, head trauma or dementia and were living at home without any difficulty. The majority of the subjects have participated in this series of studies since 1982. Using a 1.5 T superconductive MR instrument, T1-weighted, proton density and T2-weighted images were obtained. The MRI data were rated visually by regarding 12 items according to fixed criteria. T2 high signal intensity (T2HSI) lesions were found in 69.5% of subjects, the prevalence of which increased with age. T2HSI lesions were most frequently found in the basal ganglia (61.9%), followed by the thalamus (39.0%), parietal lobe (37.0%), temporal lobe (12.7%) and pons (8.5%). Among these lesions, lacunar infarction showed low signal intensity in T1-weighted images and was found in 24.6% of subjects, the prevalence also increasing with age. These findings, including brain atrophy determined according to similar criteria, were correlated closely with the subjects' age. The results of BVRT showed a close relation with T2HSI, suggesting that T2HSI may influence cognitive function. When the subjects were classified according to the presence of T2HSI, lacunar infarction and EEG abnormalities, brain atrophy was significantly milder in a group of subjects with T2HSI(-), lacunar infarction(-) and normal EEG than in the other groups. This suggests that changes seemingly representing physiological aging may be promoted by another pathological which also exerts influences on higher order cerebral function.

Aged↗

PubMed1995

Malignant hypercalcemia due to gastric endocrine cell carcinoma.

A 62-year-old man was admitted to our Neurology Unit due to consciousness disturbance. Laboratory data showed marked hypercalcemia and azotemia. Serum parathyroid hormone-related protein (PTHrP) level was extremely high. We performed intensive hemodialysis for renal failure, but his condition deteriorated rapidly. On day 10, he died of multiple organ failure. The autopsy revealed gastric undifferentiated adenocarcinoma with systemic dissemination. Immunohistological study showed positive PTHrP staining in carcinoid-like parts of the tumor. This is the first reported case of malignant hypercalcemia due to PTHrP-producing carcinoid or endocrine cell carcinoma of the stomach.

Adenocarcinoma↗

PubMed1995

Efficacy of interferon alfa therapy in chronic hepatitis C patients depends primarily on hepatitis C virus RNA level.

To clarify the viral factors that may predict the therapeutic effect of interferon (IFN) in chronic hepatitis C (CHC) patients, we investigated the quantitative serum hepatitis C virus (HCV) RNA level, genotype, and liver biopsy histological features in 60 patients who were treated with 360 x 10(6) U of natural IFN-alpha for 36 to 48 weeks and for more than 12 months after therapy. A branched DNA (bDNA) assay was used to measure HCV RNA levels. All responders, defined as those individuals with normal alanine transaminase (ALT) levels at 48 weeks after therapy, had less than 2 x 10(6) HCV RNA Eq/mL before administration of IFN. Of 39 patients with RNA levels (less than 2 x 10(6) Eq/L) 23 (59.0%) were responders. The genotype was determined for each patient using type-specific polymerase chain reaction (PCR) primers. There was a significant difference in rate of response between subtype 1b and subtypes 2a and 2b (P < .0002); however, all responders had less than 2 x 10(6) Eq/L independent of genotype. In a multivariate analysis, RNA level was the most statistically significant factor affecting response to IFN. Although disease severity, as defined by histological features, was not statistically correlated with nonresponse, patients that responded to IFN tended to have less severe disease.

Adult↗

PubMed1994

Substance P antagonist does not block the stimulation of rapidly adapting pulmonary stretch receptors by ammonia.

We investigated the effects of the substance P (SP) blocker [D-Pro2,D-Trp7,9]-SP on the response of rapidly adapting pulmonary stretch receptors (RARs) to SP administered into the right atrium, or ammonia vapor inhaled into the lungs in anesthetized, spontaneously breathing rabbits. Right atrial administration of SP (0.3, 1.0, and 3.0 micrograms/kg) caused an increase in the RAR activity, and this increase became more prominent as the dose of SP was increased. The RARs increased their activity following inhalation of vapor from 5 and 10% ammonia solutions, and the increase was concentration dependent. The excitatory responses of RAR activity to SP at different doses were greatly diminished or completely blocked by administration of the selective SP antagonist (300 and 500 micrograms/kg). However, the ammonia-induced RAR stimulation was not significantly altered by prior treatment with the SP blocker (300 and 500 micrograms/kg). These results suggest that the stimulation of RARs by ammonia does not occur as a result of the release of SP from sensory nerves in the airways and lungs.

Administration, Inhalation↗

PubMed1994

Correlation of diagnostic accuracy of dipyridamole thallium-201 myocardial scintigraphy and clinical findings during stress.

The relationship between dipyridamole thallium-201 myocardial single-photon emission computed tomography and clinical findings during stress testing was investigated in 57 patients (mean age 72 years), including 11 patients with normal coronary arteries. Systolic blood pressure decreased from 138.2 +/- 19.7 to 119.8 +/- 20.1 mmHg (mean: -13.8 +/- 6.6%) after dipyridamole infusion (0.568 mg/kg/4 min). Scintigraphic sensitivity for the diagnosis of coronary artery disease was higher in 30 patients with a systolic blood pressure decrease above the average value than in 27 patients with a blood pressure reduction of less than 14% (88% vs. 60%, p < 0.005). Reversible perfusion defects among stenosed coronary arteries were more frequent in the former group (73% vs. 27%, p < 0.001) with no difference in other clinical findings. In conclusion, systolic blood pressure change during stress testing was significantly correlated with dipyridamole-induced perfusion defects and detectability of coronary stenosis.

Aged↗

PubMed1994

[Radiation therapy of carcinoma of the esophagus in the aged--its results and problems].

Clinical records of 128 non-selected patients with esophageal cancer treated by radiation were reviewed to investigate reasons why treatment had to be discontinued, relationship between age and survival, and factors influencing prognosis. Radiation therapy was completed in 77 patients but was discontinued in 27 patients. Preoperative radiation was attempted in 24 patients. An overall median survival of 128 patients was 6.4 months, with 8.5 and 3.3 percent surviving 3 and 5 years. Median survivals of incomplete RT, completed Rt and RT + Surgery were 1.3, 7.7 and 11.3 months. By Kaplan-Meier analysis significant difference was observed in survival rate between incomplete RT and the other two groups, but not between RT and RT + surgery. T1 tumor cases with incomplete RT were characterized by a higher C-Score (higher incidence of comorbidity and complications), lower albumin concentration and poor performance status. Median survivals of 60 years, 70 and 80 were 12, 5.4 and 6.2 months, respectively. Performance status and C-score were significantly different between the 60 yr and 80 yr groups. Survival rates were also apparently affected by the size of the primary tumor and metastasis. Thus important factors influencing prognosis were performance status, albumin concentration, and comorbidity and complications, in addition to stage of tumor itself. Although performance status and albumin concentration were considered directly related to tumor stage, old age may have an adverse effect on these factors through increase of comorbidity and complication. The data may be useful for decision making for treatment of esophageal cancer of the aged.

Age Factors↗

PubMed1993

H1- and H2-receptor influences of histamine and ammonia on rapidly adapting pulmonary stretch receptor activities.

Studies were designed to establish the difference of the excitatory mechanisms between histamine and ammonia on rapidly adapting pulmonary stretch receptors (RARs). We therefore examined the responses of RARs to histamine administered as an aerosol and ammonia inhaled as a vapor before and after aerosol administration of mequitazine or cimetidine in spontaneously breathing rabbits. The excitatory responses of RARs to aerosols of histamine at different concentrations were completely blocked by administration of aerosol mequitazine but potentiated by aerosol cimetidine. However, the increases of RAR activity produced by inhalation of ammonia vapor at different concentrations were not significantly affected by aerosol administration of either a H1-receptor blocker or a H2-receptor antagonist. These results suggest that the stimulation of RARs by aerosol histamine occurs as a result of the interaction between H1 (excitatory)- and H2 (inhibitory)-receptor effects, whereas these two receptor effects do not contribute to the ammonia-induced RAR stimulation.

Administration, Inhalation↗

PubMed1993

[MRI study of the brain in aged volunteers: T2 high signal intensity lesions and high cortical function].

In order to characterize age-related and chronological changes of the brain, longitudinal studies of aged volunteers were conducted using computed tomography since 1982. The present paper discusses correlations between brain function and findings of MR images which were obtained a using 1.5 T superconductive MR instrument since 1989. A total of 118 volunteers aged 60 to 88 years old with a mean age of 75.0 +/- 6.7 participated in the study, which consisted of MRI, EEG recording, the Benton Visual Retention Test and a medical interview. Subjects with a past history or clinical evidence of CVD, head trauma or dementia were excluded from the study. Incidence of T2 high signal intensity lesions increased with age. Some showing T1 low signal intensity in the same lesion were considered to be lacunar infarction, over all incidence of which was 24.6%. Numbers of correct responses on the BVRT showed a negative correlation with numbers of T2 high signal intensity lesions. Although the aged volunteers in the present study could achieve all activity of daily living without any trouble, high cortical function evaluated by visuoperceptual performance of BVRT was somewhat disturbed in participants with multiple T2 high signal intensity lesions. Brain atrophy seems to be more advanced in groups with T2 hyper intensity lesions than in the group without them. These findings may support the notion that T2 high signal intensity lesions are not merely an index of ageing but pathologic lesions accompanied with senescence, although further studies including clinicopathological correlation are necessary to establish this concept.

Aged↗

PubMed1993

[Clinical evaluation of age-related changes of bone mineral content of cortical and trabecular bones by dual energy QCT].

The potential capability of a new dual energy (DE) quantitative computed tomography (QCT) method, 4-equation 4-unknown method (DEQCT4E-4U), was evaluated for estimation of bone mineral density (BMD) as well as bone mineral content/cm width (BMC) in trabecular bone of lumbar vertebrae. Cortical BMD and BMC were also estimated by the single energy QCT method (SEQCT 80 kVp) and the age-related change of cortical BMD and the cortical BMC/trabecular BMC ratio was also studied. The result indicated that the estimation of the BMD combining analysis of BMC in trabecular bone obtained by the present method provides further knowledge concerning vertebral trabecular bone mineral status. The profiles of the age-related changes of the cortical BMD and cortical BMC/trabecular BMC ratio in females were markedly different from those in males. These results indicated that our method combining analysis of BMC (BMD) of cortical bone and trabecular bone was also found to provide valuable information to evaluate the vertebral bone mineral status.

Absorptiometry, Photon↗

PubMed1993

Immunohistochemical localization of ganglioside components in hepatocellular carcinoma and liver cirrhosis using monoclonal antibody.

BACKGROUND: In our previous studies (1, 2) a remarkable difference in the patterns of gangliosides was demonstrated between normal human liver and hepatocellular carcinoma (HCC) on thin layer chromatography, consisting of a marked increased in GM2 and the unidentified gangliosides. The proliferation of the unidentified gangliosides was also revealed in certain types of liver cirrhosis. The precise chemical structure of the unidentified components still remains to be elucidated, and there are no comprehensive data on these components investigated in liver tissue from patients with liver cirrhosis, HCC, or malignancies of the biliary and gastrointestinal tracts. In view of this, we studied the immunohistochemical localization of these ganglioside components in these tissues. EXPERIMENTAL DESIGN: Two unidentified gangliosides were extracted and monoclonal antibody were prepared. Localization of these gangliosides on tissue sections of liver obtained from HCC and liver cirrhosis, and malignancies of the biliary and gastrointestinal tracts was investigated by performing immunohistochemical staining using monoclonal antibody. The carbohydrate composition and sialic acid species of these components were determined by gas-liquid chromatography analysis. The sialic acid linkage to the terminal moiety of these components was also investigated by sialidase treatment. RESULTS: Staining with monoclonal antibody against specific gangliosides revealed dense brown granules in HCC tissue sections, whereas normal liver, kidney, and spleen sections were negative. Tissue sections of cirrhotic livers generally stained weakly except one case that showed slight to moderate staining. These antigens were immunohistochemically negligible in sections from one case each of gastric, colon, and common bile duct cancer. The ganglioside components identified in HCC were confirmed to be sialosylparagloboside with an alpha 2-6galactosyl terminus as determined by gas-liquid chromatography analysis and enzymatic hydrolysis with different sialidases. CONCLUSIONS: These components may be a useful marker in the detection of HCC and for subclassification of HCC from the standpoint of ganglioside metabolism.

Adult↗

PubMed1992

Characteristics and management of patients with fetal neuroblastoma.

At 35 weeks 6 days of gestational age, ultrasound evaluation of the fetal abdomen showed a mixed cystic mass in the superior pole of the left kidney. The mass was suspected to be an adrenal hemorrhage or neuroblastoma. The diagnosis was fetal neuroblastoma. Differential diagnosis enabled the fetal neuroblastoma to be distinguished from adrenal hemorrhage. The parameters of diagnosis of fetal neuroblastoma include no specific ultrasonographic pattern, lack of palpability, and no tumor markers. However, certain features do characterize fetal neuroblastoma, such as little metastases, complete resection at operation, and excellent prognosis. In cases of suspected neuroblastoma, a laparotomy performed as soon as possible is generally regarded as the best course of treatment. Nonetheless, biological analyses of the tumor may prove in the future to be necessary for determining whether or not laparotomy is the best treatment.

Adrenal Gland Diseases↗

PubMed1992

A non-radioisotopic reverse transcriptase assay using biotin-11-deoxyuridinetriphosphate on primer-immobilized microtiter plates.

We developed a non-radioisotopic (non-RI) reverse transcriptase assay (RTA). The reverse transcriptase (RT) incorporates biotin-11-deoxyuridine-triphosphate (bio-dUTP) using a poly(rA) template hybridized with oligo(dT) primer that is immobilized on the surface of a 96-well microtiter plate. This assay is thus semi-automated by adapting it to an ELISA testing format. The incorporation of bio-dUTP was enhanced by adding cold dTTP to the reaction mixture, optimally in a molar ratio 4:1 (dTTP:bio-dUTP). This non-RI RTA is more sensitive than the conventional RI assay for the detection of purified Rous-associated virus 2 (RAV-2) and of human immunodeficiency virus type 1 (HIV-1) lysate. Because of its simple procedure, higher sensitivity and non-use of RI materials, the assay can be utilized not only for virological studies but also for routine safety screening of biological products for retroviral contamination.

Avian Leukosis Virus↗

PubMed1992

[MR study of the brain stem in elderly subjects].

Findings in patients in whom brain stem lesions were suspected were studied by a high-field-strength (1.5 T) MR imager. MR scans were obtained in 97 patients over a 10-month period. The mean age was 71 years (range, 39-94 years). A high incidence of infarction and lesions showing a high signal on T2-weighted image, but an almost normal signal on the T1-weighted image were observed at the pons in elderly cases. Furthermore, cases in which these two findings were observed, had a high incidence of lesion at other regions than pons. Cases with a past history of hypertension had higher incidence of lesions at the pons than normotensive patients (alpha less than 0.01). These findings suggest that MRI examination in the elderly could detect a high incidence abnormal lesions at the brain stem as well as in basal ganglia.

Aged↗

PubMed1991

A monoclonal antibody to scopolamine and its use for competitive enzyme-linked immunosorbent assay.

A hybridoma clone producing a monoclonal antibody (SC78.H81) against scopolamine was established. The monoclonal antibody was an IgG1 (k) antibody with high affinity (1.6 x 10(9) M-1 for methylscopolamine). The monoclonal antibody was cross-reactive with methylscopolamine and butylscopolamine, and showed weak cross-reactivity with 6 beta- and 7 beta-hydroxyhyoscyamine. The cross-reaction with L-hyoscyamine, atropine, scopine and DL-tropic acid was very weak. A competitive enzyme-linked immunosorbent assay using SC78.H81 was established to quantify scopolamine. The sensitivity of the assay allowed detection of 20 pg assay-1 (0.2 ng ml-1) of scopolamine. The assay was applied to the estimation of scopolamine content in hairy root cultures of a Duboisia hybrid.

Antibodies, Monoclonal↗