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Biomedical subjects

N Tanabe

Publications and source records attributed to N Tanabe.

At least 91 records · Page 5Linked to original sources

Property variations of stone casts following high-temperature sterilization.

The effects of high-temperature sterilization methods (boiling, dry-heating, autoclaving and chemiclaving) on the properties of four types of stone cast were determined. SEM observations were made of the cast surface before and after sterilization. High-temperature sterilization affected the properties of the stone casts. Boiling, dry-heating and autoclaving were considered to be unacceptable methods for sterilizing stone casts before making prosthetic restorations.

Calcium Sulfate↗

[A case of pulmonary thromboembolism associated with heparin-induced thrombocytopenia].

A 41-year-old man was admitted to our hospital for dyspnea on exertion and chest oppression. He was diagnosed as having pulmonary thromboembolism by pulmonary perfusion scan and angiography. An anticoagulant (heparin) and fibrinolytic (urokinase) therapy were administered to him as standard therapy. Six days after continuous infusion of heparin, however, he complained of worsening of dyspnea associated with severe hypoxemia and thrombocytopenia. Because heparin-induced thrombocytopenia was suspected, heparin administration was discontinued. Shortly after switching anticoagulant therapy from heparin to warfarin, the patient's symptom improved and his platelet count returned to the pretreatment value. In this case, it was thought that an immune-mediated response contributed to this heparin-induced thrombo-cytopenia. Moreover, we revealed platelet aggregating factor in the patient's plasma. This case illustrates that caution must be taken in the use of heparin for anticoagulant therapy in patients with pulmonary thromboembolism.

Adult↗

[A case of primary pulmonary artery sarcoma].

A 39-year-old male was admitted with persistent cough, palpitations and dyspnea on exertion. Chest X-ray showed cardiomegaly, left pleural effusion and left hilar mass shadow. Echocardiogram revealed dilatation and hypertrophy of the right atrium and ventricle. Perfusion lung scintigram disclosed a complete defect of the left lung and a partial defect of the right upper lobe. CT scan showed an intravascular tumor mass in the bilateral main pulmonary arteries. Digital subtraction angiography of the pulmonary artery revealed complete obstruction of the left pulmonary artery and stenosis of the right pulmonary artery. MR image showed intravascular tumor infiltrating the mediastinum and surrounding tissue. Sarcoma was highly suspected, but a histopathological diagnosis could not be made. The patient died of heart failure two months after admission to our hospital. Postmortem examination showed that the pulmonary trunk and left main pulmonary artery were markedly dilated and completely occluded by the tumor. Tumor infiltrated into the left upper lobe and mediastinal lymph nodes. The tumor was histologically diagnosed as undifferentiated sarcoma.

Adult↗

[A cross-sectional study on relationships between daily physical activity and concentration of serum cholesterol and body mass index in fifth grade elementary schoolchildren and their parents].

The purpose of this study was to estimate the effects of daily physical activity on serum total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C), body mass index (BMI) and atherogenic index (AI) in 240 fifth grade schoolchildren, their 174 fathers and 212 mothers. Information on daily physical activity was obtained by inquiry with a questionnaire and was also measured directly with a device sensing acceleration of physical movement. In schoolchildren, effect of physical activity on TC, HDL-C and AI was not apparent, but that on BMI was shown. In adult men, HDL-C differed by job classification and increased as the degree of physical labor increased from desk work to light and heavy work. Strength of physical activity using the quotient of total amount of measured physical activity divided by body weight had a significant positive correlation with serum HDL-C (r = 0.20, p < 0.05) and significant negative correlation with AI (r = -0.18, p < 0.05) in adult men. In adult women, daily physical activity did not have a significant correlation to TC, HDL-C, AI or BMI. These results appear to suggest that the effect of daily physical activity on serum cholesterol, AI, BMI of schoolchildren and adult women was smaller than that for adult men.

Adult↗

[Pulmonary hemodynamic effects of cold pressor test in patients with chronic lung disease].

Cold Pressor Test (CPT) was applied to patients with chronic lung disease, including primary pulmonary hypertension, and the effects on pulmonary circulation were compared to those on systemic circulation. HR PPA, and TPR showed maximum values at the end of CPT (Time = 0) and recovered to baseline values 5 min after CPT. CO, however, did not change significantly after CPT. PPA and PAR showed maximum values at the end of CPT and then gradually decreased, but still were significantly higher than baseline values at 5 min after CPT. Nifedipine (NFP) reduced the maximum values of both TPR and PAR at the end of CPT. There was significant correlation between PPA change after CPT and baseline PPA value, and NFP decreased the slope of the regression line. These results indicate that cold stimulation induces both systemic and pulmonary vasoconstriction in patients with chronic lung disease, and this pulmonary vasoconstriction was correlated to the baseline pulmonary vascular tone. Moreover, nifedipine may reduce this cold stimulation-induced pulmonary vasoconstriction.

Chronic Disease↗

[Seasonal variation of sudden death based on analysis of death certificate information].

Seasonal variation of sudden death (SD) was studied based on analysis of death certificates of all 8,519 SD patients, aged 15 years or older, who died during 1984 to 1986 in Niigata prefecture, Japan. SD was defined as death within 24 hours of onset of the underlying cause. SD showed a significantly high incidence during the cold season. When analyzed by underlying cause, the high incidence during cold season was shown for SD by circulatory diseases such as acute myocardial infarction (AMI; n = 1,446), other cardiovascular diseases (OCD; n = 4,375) and cerebrovascular accident (CVA; n = 1,725). However, no significant seasonal variation was observed for SD by non-circulatory diseases. By age group, the incidence of SD due to circulatory diseases was high during the cold season in the elderly (61 to 75 years) and the old age (76 years or older) groups, irrespective of kinds of the diseases, whereas the pattern varied by disease type in the young to middle age group (15 to 60 years). The highest incidence of SD due to AMI in the young to middle age group occurred in January with a second peak in July to August. Thus, not only low temperatures but high temperatures seemed to also contribute to the occurrence of SD by AMI in this age group. While SD due to OCD in this age group did not show a significant seasonal variation, that due to CVA showed a high incidence during cold season similar to the older age groups. These results suggest that factors affecting the occurrence of SD differed according to underlying cause and age of victims.

Age Factors↗

Digital imaging techniques for dental alloy castability quantification.

In this study, mesh monitors cast from experimental compositions of a Ni-Cr-Be alloy are evaluated by the application of image analysis techniques. Castability values obtained by this method are then contrasted with those from three commonly employed manual counting procedures. While castability values obtained by all methods reflect the effect of compositional variations, a comparison of results with respect to evaluation method indicates that the image analysis technique consistently yields higher castability values, especially evident in the poorly casting groups. The apparent explanation for these observed differences is that with imaging, segments that are partially cast to varying degrees are not arbitrarily eliminated from the data, as is the usual practice in manual counting methods; therefore, castability values obtained by using the imaging technique will very closely reflect an actual alloy volume of each cast monitor.

Beryllium↗

Ca(2+)-dependent and -independent components of transmitter release at the frog neuromuscular junction.

1. When a Ca2+ chelator, bis (O-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA), was loaded into the presynaptic nerve terminal of the frog neuromuscular junction (NMJ), facilitation, measured as an increase in endplate potential (EPP) amplitudes during a train of ten stimulations at 100 Hz, was greatly decreased within 20 min of BAPTA-AM (the acetoxymethyl ester of BAPTA) perfusion, and remained at a constant low level thereafter, suggesting that [Ca2+]i at the presynaptic nerve terminal was buffered by BAPTA. 2. Detailed examination of the two components of facilitation of EPP amplitude in the BAPTA-loaded NMJs showed that the fast component was lost almost completely, while the slow component was unaffected by loaded BAPTA. Augmentation and potentiation were also unaffected by BAPTA. 3. Under external Ca(2+)-free conditions (with 1 mM-EGTA), both augmentation and potentiation of miniature endplate potential (MEPP) frequency were clearly observed after tetanic stimulation in the normal NMJ, and were also unaffected by loaded BAPTA. 4. The above findings strongly support the residual Ca2+ hypothesis for the fast component of facilitation, and suggest that the three slower processes (the slow component of facilitation, augmentation and potentiation) occur independently of [Ca2+]i. This Ca2+ independence was supported by the fact that facilitation and potentiation have multiplicative effects on the amount of release. 5. The quantal content of the first EPP in the train remained unchanged throughout the time course of BAPTA loading for most NMJs. This suggests that [Ca2+]i immediately adjacent to Ca2+ channels at the active zone triggers transmitter release and is little affected by loaded BAPTA. 6. MEPP frequency was almost unchanged during BAPTA loading, suggesting that the basal [Ca2+]i remained unchanged close to the dissociation constant of BAPTA for Ca2+ (108 nM). 7. The slow component of facilitation had a multiplicative relationship with augmentation and potentiation, suggesting that the underlying mechanism for the slow component of facilitation differs from that for augmentation and potentiation.

Animals↗

[Effects of smoking and drinking habits and vitamin A intake on serum concentrations of beta-carotene and retinol].

Serum samples from 341 males aged 10 to 59 years were obtained and stored at -40 degrees C until examined for retinol and beta-carotene concentrations by HPLC, and their relationships to smoking habit, alcohol drinking habit and vitamin A intake were studied. In univariate analysis the serum beta-carotene level was significantly lower in the smokers than in the non-smokers (smokers: 4.6 micrograms/dl, non-smokers: 7.1 micrograms/dl, p less than 0.01) and lower in the drinkers than in the non-drinkers (drinkers: 4.6 micrograms/dl, non-drinkers: 7.3 micrograms/dl, p less than 0.01). The serum retinol level was not different by smoking habit but was higher in the drinkers than in the non-drinkers (drinkers: 80.4 micrograms/dl, non-drinkers: 67.0 micrograms/dl, p less than 0.01). Serum beta-carotene was higher in the group with a greater intake of vitamin A of vegetable origin (6.1 micrograms/dl) than in the group with a smaller intake of it (4.7 micrograms/dl) (p less than 0.01), but serum retinol was not different by the amount of vitamin A intake of animal food origin. To estimate the respective effects and interactions of the above factors on serum beta-carotene and retinol levels by adjusting for the confounding effects of age, serum total cholesterol, HDL-cholesterol and triglyceride, analysis of covariance was performed. For serum beta-carotene, smoking habit (p less than 0.01), drinking habit (p less than 0.01) and the amount of vitamin A intake of vegetable food origin (p less than 0.05) had significant main effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Successful treatment of idiopathic plasmacytic lymphadenopathy with polyclonal hypergammaglobulinemia.

A 51-year-old male was admitted because of eyelid edema and anosmia, which developed in 1985. He showed bilateral cervical lymphadenopathy, with nodes larger than 2 x 2 cm, and remarkable eyelid edema. Anemia, hyperimmunoglobulinemia with hypo-albuminemia (no M-protein) and liver dysfunction were found. Bone marrow, renal function, urine analysis and LDH level were normal. Cervical lymph node biopsy showed interfollicular proliferation of plasma cells without any malignant appearance. On day 3 of oral prednisolone (PD), anosmia abruptly improved from day 7, eyelid swelling, cervical lymphadenopathy and gammopathy subsided gradually. Since PD was tapered off, no relapse has been observed thus far.

Castleman Disease↗

[Relationship between signal intensity of blood flow in the pulmonary artery obtained by magnetic resonance imaging and results of right cardiac catheterization in patients with pulmonary disease].

Electrocardiogram-gated spin-echo magnetic resonance (MR) images of the chest were obtained in five normal controls and 35 patients with pulmonary disease (11 chronic obstructive pulmonary disease, 6 pulmonary thromboembolism, 5 primary pulmonary hypertension, 4 interstitial pulmonary disease, 4 pulmonary hypertension with disturbance of portal circulation, and 5 other diseases) who underwent right cardiac catheterization. In transverse images at the level of the right main pulmonary artery (rPA) and sagittal images at the level through the midsternal line and the spinal chord, the signal intensity of blood flow in the rPA was quantitatively evaluated, and the correlations with the MR signal intensity of intravascular flow and the parameters of hemodynamics were studied. In diastole MR images of both normal controls and patients mostly showed a significant signal intensity of flowing blood, but in systole some patients demonstrated significant signals and visible flow images. In systolic MR images, the mean values of hemodynamic parameters (mean pulmonary arterial pressure (mPAP), pulmonary arteriolar resistance (PAR), and cardiac index (CI)) were abnormal in patients with significant signal intensity of flow compared with those in patients without sufficient MR signal. The signal intensity was not correlated with mPAP; however, it significantly increased as PAR increased, and it increased as CI decreased both in diastole and in systole. Especially in systole, there was good correlation between the signal intensity in transverse MR images and CI (r = -0.85, P less than 0.01) and between signal intensity in sagittal MR images and PAR (r = 0.90, P less than 0.01). These results suggest that significant flow signal in the rPA in systole has pathophysiological significance, and signal intensity is considered to be significantly affected by changes of PAR and CI. The signal intensity of blood flow in the rPA on MR images can be used as an index of the severity of right heart failure associated with pulmonary disease. MR imaging is a useful modality to evaluate pulmonary circulation disturbance because of its ability to assess blood flow in the pulmonary artery noninvasively without interference from other structures such as bone and normal lung.

Adult↗

[Correlation of signal intensity of blood flow in the pulmonary artery on MR images and clinical features of two cases of primary pulmonary hypertension].

ECG-gated spin-echo MR images of the chest were obtained in two patients with primary pulmonary hypertension (PPH). In transverse section at the level of the right main pulmonary artery (rPA), flow signals in the rPA were quantitatively evaluated, and the correlations with MR signal intensity of intravascular flow and data of routine clinical examinations and the severity of clinical manifestations were studied. In one case, the signal intensity of flowing blood markedly increased with exacerbation of hypoxemia and other clinical manifestations. However, in the other case with a stable course, the signal intensity of intravascular flow did not change significantly. Increase of flow signal in the rPA can reflect decrease of flow velocity that may be cause by a state of high pulmonary vascular resistance or low cardiac output. Therefore, it is suggested that MRI is a useful modality to evaluate the severity of disturbance of the pulmonary circulation in PPH.

Adolescent↗

[Circadian variations of sudden death].

Characteristics of the circadian variation for sudden death (SD), were studied by analyzing summary death certificates for the period of 1984 to 1986 in Niigata prefecture. SD was defined as death within 2 hours of onset of underlying cause (n = 4,362), and the time of onset of the cause was determined by subtracting the "time elapsed until death" from the "time of death." The periodicity for time of onset of the cause was analyzed in groups stratified by year, season, sex and age with Rogers' method utilized to check the statistical significance of the periodicity. SD, as a whole, showed a statistically significant circadian variation with a low incidence during 0 to 4 A.M. and a high incidence during 6 to 8 A.M. and 6 to 8 P.M. By season, no significant circadian variation was seen in the summer unlike for other seasons. When analyzed by age group, no significant circadian variation in SD was seen for the young to middle aged group (15-54 years old). On the other hand, there was a significant circadian variation for the senior (55 to 74 years old) and the elderly group (75 years old or older) with a low incidence during 0 to 4 A.M. and high incidence during 6 to 12 A.M. and 6 to 8 P.M.. For the old age group, the number of the cases increased so remarkably as to form an evening peak. The percentage of SD for young to middle cases was higher in the summer than in the other seasons which may be the reason for absence of significant circadian variation in the summer.

Adolescent↗

Pharmacokinetics of cis-diammine-dichlor-platin in a hemodialysis patient.

Cisplatin (CDDP) was administered to a 49-year-old dialysis female patient with advanced uterine cervical cancer. Analysis of the pharmacokinetics of CDDP in the patient with renal failure and at hemodialysis were compared with that of patients without renal impairment. CDDP at 30 mg was administered by drip infusion. The samples were ultrafiltrated and measured its concentration of both free (F-P) and total CDDP (T-P) by atomic absorption method. The effect of hemodialysis on the concentration of CDDP was analyzed. For the control, three patients without renal impairment were administered CDDP using the same method and its concentration was measured. The T-P clearance registered no difference between dialysis patients and controls, but F-P clearance in the HD patient was almost 5-fold lower than those in control patients, showing that F-P exposure to HD patients was 5-fold greater as a consequence of delayed disposition. The protein binding rate of CDDP was more gradual than that of the controls. The T-P and F-P removal rates positively correlated to the shunt side blood F-P.

Adenocarcinoma↗

Biosynthesis and secretion of beta-thromboglobulin by a human megakaryoblastic cell line (MEG-01).

The de-novo synthesis and secretion of beta-thromboglobulin (BTG) by a human megakaryoblastic cell line (MEG-01) were studied by measuring and immunoblotting of BTG in culture supernatant and immunoprecipitation of radiolabeled BTG synthesized after incubation with [35S]methionine. It was demonstrated that BTG synthesized by MEG-01 was secreted into culture media in a monomer form having a molecular weight of 8,800. Furthermore, we purified BTG from culture medium of MEG-01 with a heparin affinity column and compared BTG from MEG-01 with that from normal platelets. The molecular weights of BTG purified from both sources were 8,800 using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). These results provide direct evidence for the synthesis and secretion of BTG by megakaryocytes.

Blood Platelets↗

[Past histories of sudden death without specific underlying disease].

To study past histories of patients who died suddenly, we selected cases from all the summary death certificates in which death occurred within 24 hours from the onset of symptoms spanning 1984 to 1986 in Niigata prefecture with a population of 2.5 million. We then re-examined all information on the death certificates to determine the underlying causes. Sudden deaths due to cardiovascular diseases other than acute myocardial infarction and cerebrovascular accident (OCD) accounted for the largest proportion (51.4%). The proportion of death of unknown etiology increased with the decrease in age in both sexes aged 15 to 54 years, accounting for 67.8% in males and 51.1% in females. The number of cases with histories of diseases related to atherosclerosis (e.g. hypertension, old cerebrovascular accident, etc) increased with age in both sexes, accounting for 38.5% in males and 36.4% in females, both aged 75 years old and over. Except diseases related to atherosclerosis, the past histories accounted for 2.5% or greater were as follows: alcoholism (4.1%), psychiatric disorder (PSY, 2.9%) and valvular heart diseases (VD, 2.6%) in 15-54-year-old males; ischemic heart diseases (IHD, 9.4%), arrhythmia without organic heart diseases (ARR, 2.5%) and VD (2.5%) in 55-74-year-old male; IHD (11.4%), bronchial asthma (3.7%), common cold within one month (CC, 3.6%), cor pulmonale or its related diseases (3.0%) and ARR (2.6%) in male of 75 years old and over; PSY (8.7%), IHD (5.8%), VD (5.1%), pregnancy, delivery or related diseases (4.4%), chronic renal failure (3.6%) and CC (2.9%) in 15-54-year-old females; IHD (10.2%), VD (3.2%) and ARR (2.6%) in 55-74-year-old females; and IHD (11.8%) in females of 75 years old and over. When diseases related to atherosclerosis were included, half of the sudden death cases due to OCD had past histories of underlying cause. As descriptions of past histories are often incomplete, there were probably more cases with past histories. The results of this study indicate that investigation of past histories may aid in elucidating and preventing sudden death.

Adolescent↗

Septicemia in patients with solid cancers in a Japanese cancer hospital--the significance of candidemia for cancer patients.

Episodes of septicemia (114) in patients with solid cancers at Nagoya Memorial Hospital were analyzed from April 1985 to June 1986. The underlying malignancies were predominantly gastric and colon cancers. Almost all the cancers were in advanced stages, the most frequent patient performance status being 4. Hypogammaglobulinemia and granulocytopenia were not, however frequent among these patients. The major microbes detected from blood cultures were Candida sp., Staphylococcus aureus and Staphylococcus epidermidis. Preceding chemotherapies were mainly combination chemotherapies containing Cisplatin (CDDP). The major pathogen, Candida sp., was detected frequently from Hickman's catheter. Thirty-one percent of patients died within 14 days of the septicemia diagnosis (two were cases of septic shock).

Anti-Bacterial Agents↗

Early site of lymphatic involvement from right renal cell carcinoma: CT demonstration and method of lymphadenectomy.

The value of lymphadenectomy in the treatment of renal cell carcinoma remains controversial. The precise location of nodal metastasis and method of lymphadenectomy had seldom been mentioned. We report 2 patients with right renal cell carcinoma who had regional lymph node involvement without blood-borne metastasis. The involved lymph nodes were demonstrated by CT scan just behind the inferior vena cava at the level of renal hilus. These nodes seemed to be the first sites of nodal involvement from the right renal cell carcinoma. Elevation of the inferior vena cava by dividing its small branches, including a few lumbar veins, was necessary for complete removal of these nodes en bloc with the right kidney.

Aged↗