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Biomedical subjects

T Tokuyama

Publications and source records attributed to T Tokuyama.

At least 73 records · Page 4Linked to original sources

Compression of the left brachiocephalic vein: cause of high signal intensity of the left sigmoid sinus and internal jugular vein on MR images.

To study the asymmetry in signal intensity of the sigmoid sinuses, internal jugular veins (IJVs), or both sets of structures on magnetic resonance (MR) images, the authors reviewed 226 serial sets of routine MR imaging studies. Cerebral digital subtraction angiography was performed in 20 patients with a markedly higher intensity and/or enhancement on the left; 15 of them also underwent venography. With every sequence, the left sigmoid sinus, IJV, or both were higher in signal intensity significantly more often than the right (range, P = .0001 to .0129). Angiography revealed hemostasis in the left IJV in 16 patients that disappeared during full inspiration in 14. In 13, venography revealed that the left brachiocephalic vein was compressed to occlusion between the aortic arch and the sternum during tidal volume ventilation. The occlusion disappeared at full inspiration, when the distance between the aortic arch and the sternum increased. This hemostasis could be the major cause of the frequent increased signal intensity of the left sigmoid sinus and IJV on MR images.

Adolescent↗

[Study on the relationship between appearance of autoantibodies and chest X-ray findings of asbestos plant employees].

Antinuclear factor (ANA) and rheumatoid factor (RF) were determined in 220 employees of an asbestos plant. The relationship of the appearance of the two factors to sex, age, smoking habit, duration of asbestos exposure and asbestos exposure level was studied. In 207 employees who had chest roentgenograms, the relationship of these two factors to pulmonary lesions and pleural lesions was examined. Of the 220 employees, 33 (15%) had ANA and 7 employees (3.2%) had RF. ANA positive rate in the asbestos plant employees was significantly higher than in the control. Factors significantly correlated to their appearance could not be demonstrated. With the progress of pulmonary lesions the ANA positive rate significantly elevated, but ANA positive rate was not significantly correlated with pleural lesions. RF did not show any significant correlation with any of the factors.

Adult↗

[Clinical features of primary and secondary atypical mycobacteriosis].

A clinical investigation was carried out in 39 patients with atypical mycobacteriosis (AM). The patients at our hospital diagnosed as having AM during an 11-year period from 1981 to 1991 were reviewed in this study. The incidence of AM among all of mycobacterial infections has been increasing since 1988. The atypical mycobacteria detected included M. avium complex (MAC) in 79%, M. kansasii in 26%, and other organisms in 5%. Patients who had primary infection without underlying respiratory disease were compared with those who had secondary infection. In secondary infection, MAC was detected in the sputum of a high percentage of patients and was positive for more than 6 months despite therapy. Gamma globulin levels were also increased in patients with secondary infection. Cell mediated immunity was examined by the DNCB reaction and the detection of CD4- and CD8- positive T lymphocytes. The DNCB skin reaction was positive in 6 out of 26 patients with secondary infection. The percentage of CD8- positive T lymphocytes was higher in patients with secondary disease. Fischer's ratio (indicating the balance of plasma amino acids) was also examined as an index of the nutritional status. It was significantly lower in secondary infection compared with primary infection. Moreover, secondary infection was associated with a lower positive rate for the DNCB skin reaction and a lower Fischer's ratio when compared with pulmonary tuberculosis. Thus impairment of cell-mediated immunity, malnutrition, and a poor prognosis were significantly more common in secondary infection compared with primary infection.

Adolescent↗

[An autopsy case of atypical mycobacteriosis accompanied with chest wall deformity].

An autopsy case of 63-year old male of atypical mycobacteriosis with severe scoliosis was reported. He was diagnosed as atypical mycobacteriosis in 1981 and controlled by antimycobacterial treatment. But since 1989, dyspnea and sputum have been increasing, new abnormal shadow in company with progression of curvature of the scoliosis was revealed on the chest roentgenogram. In spite of various treatments for mycobacteriosis, he died of respiratory failure. The aggravation of this mycobacteriosis brought on advancement of malnutrition and impairment of cell mediated immunity. Findings of autopsy showed the remarkable chest wall deformity and tuberculous change of the lung parenchyma. In this case, chest deformity was thought as the major risk factor of onset of mycobacterial mycobacteriosis.

Humans↗

[Interleukin-1 beta production by alveolar macrophages in cases of asbestos exposure].

In order to investigate the role of interleukin-1 beta secreted by alveolar macrophages in the pathogenesis of pulmonary asbestosis, we performed bronchoalveolar lavage on 12 asbestos-exposed subjects and 10 control subjects, and measured interleukin-1 beta secreted by alveolar macrophages. Interleukin-1 beta production was increased in the asbestos-exposed subjects compared to control subjects (3.1 +/- 2.2 ng/ml versus 0.8 +/- 0.4 ng/ml, p < 0.05). The period after retirement was inversely correlated with interleukin-1 beta production (r = -0.67, p < 0.05). We divided non-smoking asbestos-exposed subjects into two subgroups based on the radiographical profusion according to the ILO classification. The advanced group was defined as grade 2 or greater profusion, and the early group was defined as grade 1 or lower profusion. We found higher production of IL-1 beta in the early group than in the advanced group.

Aged↗

Preserved thyroidal secretion of thyroxine in acromegalic patients with suppressed hypophyseal secretion of thyrotrophin.

OBJECTIVE: We have assessed the mechanisms which maintain euthyroidism in acromegalic patients despite the suppression of thyrotrophin (TSH) secretion. MATERIALS: Fourteen untreated patients with acromegaly were analysed. Ten patients were also studied after pituitary surgery. METHODS: Thyroid hormones, growth hormone (GH), insulin-like growth factor-I (IGF-I) and thyroidal uptake of radioactive iodine, thyrotrophin releasing hormone (TRH) test and basal metabolic rate (BMR) were measured before and after pituitary surgery. RESULTS: Nine patients had palpable goitres. The TSH response to TRH stimulation was suppressed in eight patients, who maintained normal serum levels of total T3, T4 and free T4. The patients with normal TSH response had lower levels of free and total T4 than controls. The response of TSH to TRH correlated inversely with the serum level of total and free T4, and also with the plasma level of IGF-I (r = -0.74, P less than 0.05, n = 9). After pituitary surgery, the serum levels of total and free T4 were elevated for at least up to 6 months, with a decrease in the T3/T4 ratio and the BMR. CONCLUSION: GH may have a direct stimulatory action on the thyroid secretion of T4 possibly via increased IGF-I, despite suppressed TSH secretion. The post-operative elevation of serum T4 suggests the persistent secretion of T4 from the thyroid gland, in spite of instantaneous normalization of the accelerated conversion of T4 to T3, even after reduction of excess GH secretion.

Acromegaly↗

Thyrotoxicosis with low serum total T3 level in patients with destructive thyroiditis and non-thyroidal illness.

The serum total T3 level, evaluated in 687 patients with thyrotoxicosis diagnosed by an elevated serum free T4 level and suppressed serum TSH level, was found to be high in 98.1% and normal in 1.9% of 592 patients with Graves' hyperthyroidism, and high in 75.8%, normal in 21.1% and low in 3.2% of 95 patients with destructive thyroiditis. Non-thyroidal illness was found in about a third of the patients with thyrotoxicosis and a normal serum total T3 level. The serum total T3 level was low with elevated serum thyroglobulin and reverse T3 levels in three patients with severe non-thyroidal illness, in whom the thyroidal radioactive iodine uptake was suppressed and the thyrotoxicosis resolved spontaneously with a normalization of the serum total T3 level after recovery from the destructive thyroiditis and non-thyroidal illness. It is therefore concluded that thyrotoxicosis with a low serum total T3 level, partially due to associated non-thyroidal illness, is more frequently found in patients with destructive thyroiditis than in those with Graves' hyperthyroidism.

Adult↗

[Case study of interleukin-1 beta, tumor necrosis factor alpha and interleukin-6 production peripheral blood monocytes in patients with diabetes mellitus complicated by pulmonary tuberculosis].

Patients with diabetes mellitus (DM) show an increased susceptibility to bacterial infections due to the presence of neutrophil dysfunction. Susceptibility to tuberculosis has also been reported in such patients, however, the reason remains unclear. This study measured the production of interleukin-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF alpha) and interleukin-6 (IL-6) by the peripheral monocytes of patients diagnosed with pulmonary tuberculosis accompanied by DM (TB+DM) and patients without DM complications (TB) using age-matched, healthy control subjects for comparison. Also examined was the relationship between cytokine production and DM control. The results were as follows: (1) The production of IL-1 beta, TNF alpha and IL-6 in TB patients was significantly higher than that observed in the healthy control subjects. (2) The production of IL-1 beta, TNF alpha and IL-6 in TB+DM patients was significantly lower than that observed in the TB patients. (3) The production of IL-1 beta and TNF alpha in TB+DM patients with poor control was significantly lower than that observed in the patients with good control. (4) The TNF alpha production had a significant inverse correlation to HbA1c in the TB+DM patients. This study demonstrated that the production of cytokines is impaired in TB+DM patients and suggests a close correlation between tuberculosis immunity and DM.

Adult↗

[Three cases of young adults advanced pulmonary tuberculosis due to patient's and doctor's delay].

Three young adults advanced pulmonary tuberculosis due to delay of therapy were reported. In case 1 and 3, their delays resulted from difficulty in diagnosis, in case 2, from neglecting medical counseling. Each cases revealed bilateral diffuse shadows on chest roentgenograms on admission, which were typical shadows of advanced pulmonary tuberculosis. Malnutrition might contribute to the development of the diseases, which were improved by anti-tuberculosis therapy and hyperalimentation therapy. These cases were suggested some clinical problems characteristic of pulmonary tuberculosis of young adults.

Adult↗

[Nutritional assessment and the effect of supplementary oral nutrition in patients with pulmonary emphysema].

Nutritional status and its relation to respiratory function and respiratory muscle strength were assessed in patients with pulmonary emphysema. Energy metabolism was also examined in order to elucidate the mechanism of their malnutrition. BCAA/AAA ratio of plasma amino acid was positively correlated with FEV1.0%. Resting energy expenditure (REE) was negatively correlated with FEV1.0%, and REE/REEpred ratio was also negatively correlated with BCAA/AAA and PImax. These findings suggest that increased mechanical work load, associated with airway obstruction and reduced respiratory muscle efficiency, contribute to the increased energy expenditure and amino acid imbalance. Oral nutritional supplementation using BCAA enriched-elemental diet was found to be effective, as assessed by nutritional parameters, PImax, D.O.E., and QOL index, in malnourished emphysema patients.

Aged↗

[Relation of airway obstruction and respiratory muscle weakness to energy metabolism in pulmonary emphysema].

Resting energy expenditure (REE) was assessed and its relationship to nutritional status, pulmonary function and respiratory muscle function was studied in 25 patients with pulmonary emphysema. The mean value of REE was 1413 +/- 251 Cal and the ratio of REE/REEpred was 1.398 +/- 0.23, suggesting the existence of a hypermetabolic state in these patients. REE/REEpred ratio was inversely correlated with plasma amino acid BCAA/AAA ratio and body muscle mass; and PImax. REE was inversely correlated with FEV1.0%. REE in the patient subgroup with severe hyperinflation (%RV > or = 200) was significantly higher than that in the subgroup with moderate hyperinflation. Malnourished patients showed significantly more severe hyperinflation than well-nourished patients. These findings suggest that augmented REE contributes to malnutrition in patients with emphysema, and that the increase in REE was related to the increase in mechanical work load on the basis of airway obstruction, respiratory muscle weakness and hyperinflation.

Aged↗

[Supplementary nutrition therapy is effective in patients with chronic obstructive pulmonary disease].

We examined the effects of supplementary nutritional therapy (calorie:REEx1.5) for one year using branched-chain amino acid (BCAA) enriched-elemental diet in addition to usual diet in 12 malnourished patients with COPD. Improvement in nutritional status was assessed by BW, %IBW, %AMC, transferrin, and plasma amino acid BCAA. PImax was significantly increased after 3 months' therapy. Although no significant change was found in pulmonary function and arterial blood gases, subjective symptoms evaluated by D.O.E., oxygen cost score and QOL index were improved. Significant correlations were found between delta BW and delta AMC and delta TSF, delta PImax and delta AMC, delta oxygen cost score and delta PImax, which suggest that improvements in nutritional status contributed to the improvement in respiratory muscle function and subjective symptoms. These findings suggest the effectiveness of supplementary nutritional therapy using BCAA-enriched elemental diet in patients with COPD.

Aged↗

[Evaluation of tissue eosinophils in eosinophilic pneumonia].

Transbronchial biopsy specimens from ten patients with eosinophilic pneumonia were analysed to see whether the tissue contained activated eosinophils or secreted eosinophil cationic protein. The specimens showed many infiltrated tissue eosinophils in the intraalveolar spaces, and thickened alveolar septae and perivascular areas. Most of these eosinophils stained clearly with degranulation by immunohistochemical studies with monoclonal antibody EG2 (for the secreted form of eosinophil cationic protein), indicating that they were activated eosinophils. On the other hand, although pleural tissue obtained at bullectomy performed after pneumothorax showed eosinophilic infiltration, EG2-positive cells were few. Activated eosinophils may play an important role in the development of pulmonary lesions of eosinophilic pneumonia.

Adolescent↗

[The relationship between TSH response to TRH and GH response to dopaminergic agents in patients with acromegaly].

The role of dopaminergic agents (DA) in the regulation of growth hormone (GH) secretion was investigated in patients with untreated acromegaly. TRH (0.5 mg iv), bromocriptine (Br) (2.5 mg orally) or L-Dopa (500 mg orally) loading tests were performed, and serum levels of TSH, GH and prolactin (PRL) were measured. Patients were defined as responders to TRH when peak TSH level after TRH test was higher than 5 microU/ml. Br or L-Dopa was considered to be effective when serum GH or PRL levels were suppressed more than 50% of the basal value. The patients were classified into large adenoma group with suprasellar extension or cisternal herniation (L group, n = 7) and intrasellar small adenoma group (S group, n = 11) which was further divided into TRH responder (Sr group, n = 4) and TRH non-responder with suppressed TSH (Ss group, n = 7). Br was effective in 7 or 100% of 7 patients in the Ss group but only in one or 25% of 4 patients in the Sr group. Br was also effective in 5 or 71% of 7 patients in the L group, although most of them were responders to TRH. Percent inhibition of serum GH levels by Br was significantly higher in the Ss group (82.3 +/- 12.3%, p less than 0.001) and in the L group (64.7 +/- 20.5%, p less than 0.05) compared with that in the Sr group (29.3 +/- 21.6%). Suppression of serum GH level by L-Dopa was also observed in the Ss group. In contrast to the difference in the response of GH, serum PRL level was equally suppressed by Br or L-Dopa in each group. Suppression of TSH by administration of exogenous T4 had no effect on the GH suppression effect of Br in the Sr group. Considering the dual effects of DA to enhance growth hormone-releasing hormone (GHRH) secretion in the hypothalamus and to suppress GH secretion in the pituitary gland, these findings suggest that the paradoxical effect of DA to suppress serum GH level is observed when the hypothalamo-pituitary axis is disturbed mechanically by large adenoma in the L group or functionally in the Ss group probably due to enhanced secretion of somatostatin which suppresses TSH secretion and impairs the effect of GHRH.

Acromegaly↗

Decahydroquinoline alkaloids: noncompetitive blockers for nicotinic acetylcholine receptor-channels in pheochromocytoma cells and Torpedo electroplax.

In pheochromocytoma PC12 cells, (+)-cis-decahydroquinoline 195A (5-methyl-2-propyl-cis-decahydroquinoline) and (+)-perhydro-cis-decahydroquinoline 219A (2,5-dipropyl-cis-decahydroquinoline) inhibit carbamylcholine-elicited sodium flux with IC50 values of 1.0 and 1.5 microM, respectively. Both of these decahydroquinolines appear to enhance desensitization, although apparent lack of complete removal of (+)-perhydro-cis-219A by washing complicates interpretation of the effects of that agent. A series of cis- and trans-decahydroquinolines with substituents in the 2- and 5-position also exhibit structure-dependent inhibition of carbamylcholine-elicited sodium flux in PC12 cells and all of the decahydroquinolines inhibit binding of the noncompetitive blocking agent [3H]perhydrohistrionicotoxin to muscle-type nicotinic acetylcholine receptor-channels in membranes from Torpedo electroplax. The Ki values in electroplax membranes range from 1.4 to 7.9 microM, making these alkaloids comparable in potencies to the histrionicotoxins. Potencies are increased 2- to 3-fold in the presence of an agonist, carbamylcholine. The profile of activities are similar in PC12 cells and electroplax membranes. The cis- and trans-decahydroquinolines represent another class of noncompetitive blockers for acetylcholine receptor-channels with similar activity for both muscle-type and ganglionic type nicotinic receptors.

Alkaloids↗

5,8-disubstituted indolizidines: a new class of noncompetitive blockers for nicotinic receptor-channels.

A series of 8-methyl-5-substituted indolizidines inhibit binding of the noncompetitive blocking agent [3H]perhydrohistrionicotoxin to muscle-type nicotinic acetylcholine receptor-channels in membranes from Torpedo electroplax. The Ki values range from 0.16 to 1.12 microM, making these alkaloids among the most potent ligands for this site. Unlike most noncompetitive blockers, the potencies of the 8-methyl-5-substituted indolizidines are reduced in the presence of carbamylcholine. Indolizidine 205A (8-methyl-5-(4-pentynyl)indolizidine) is unique in enhancing binding of [3H]perhydrohistrionicotoxin by 1.5-fold. The enhancement is at a maximum at 0.01 to 0.1 microM, followed by progressive inhibition with an IC50 of about 20 microM. In the presence of carbamylcholine, which itself enhances binding of [3H]perhydrohistrionicotoxin, indolizidine 205A causes only an inhibition of binding with an IC50 of about 10 microM. Indolizidines with a hydroxy substituent on the 8-methyl group have very low activity. None of the indolizidines affect binding of [125I]alpha-bungarotoxin to acetylcholine recognition sites. In pheochromocytoma PC12 cells, indolizidine 205A has no agonist activity, but only inhibits carbamylcholine-elicited 22Na+ influx. The profile of potencies for the 8-methyl-5-substituted indolizidines is similar in electroplax membranes and PC12 cells. Indolizidines 205A and 209B (8-methyl-5-pentylindolizidine) have no apparent effect on desensitization of receptors in PC12 cells. The 5,8-disubstituted indolizidines appear to represent an atypical and potent class of noncompetitive blockers for muscle-type and ganglionic nicotinic receptor-channels.

Animals↗

Prediction of relapse in drug-treated Graves' disease using thyroid stimulation indices.

Thyroid stimulation indices such as high thyroidal radioactive iodine uptake, increased estimated thyroid weight, presence of TSH-binding inhibitor immunoglobulin or thyroid-stimulating antibody, and elevated serum thyroglobulin level, were evaluated in 148 patients with Graves' disease who had been treated with antithyroid drugs for two years or more before the drugs were withdrawn. In all 19 patients in whom three or more indices were positive, early relapse, within 12 months, occurred after reducing the dosage of antithyroid drugs. Other 129 patients were followed after the drug was withdrawn and in 77 patients with one or two positive indices, early relapse occurred in 65-71% and late relapse, after 12 months or later, occurred in 2-11%. In 52 patients in whom none of the indices were positive, 86% remained in remission, but 10% developed an early relapse, and 4% a late relapse. We conclude that a combined analysis of thyroid stimulation indices is useful in predicting relapse in Graves' disease whereas it remains difficult to predict permanent remission.

Adolescent↗

Purification and some properties of protease I having transfer action from Streptomyces griseus var. alcalophilus.

Streptomyces griseus var. alcalophilus was selected because it secreted a unique protease (protease I) that catalyzed the transfer reaction forming the hydroxamic acids of various amino acids. Protease I was purified to the electrophoretically homogeneous state and an activity of more than 125-fold that of the culture broth. The molecular weight of the enzyme was estimated to be 25,000 by gel filtration. The enzyme was most active in neutral pH for the transfer reaction forming phenylalanine hydroxamic acid, although for the hydrolytic reaction with casein as substrate it was most active in alkaline pH. The enzyme was inhibited by diisopropylfluorophosphate. Protease I catalyzed the transfer reaction synthesizing the hydroxamic acids of hydrophobic, acidic, basic, and small aliphatic amino acids such as Phe, Tyr, Leu, Asp, Glu, Arg, Lys, Ala, and Gly. These results indicate that protease I has broad donor specificity. It is also considered that protease I is a unique enzyme with transfer activity, and distinct from the alkalophilic proteinase reported previously [Yamamoto et al., Agric. Biol. Chem., 38, 37 (1974)].

Amino Acid Sequence↗