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Biomedical subjects

A Yoshida

Publications and source records attributed to A Yoshida.

At least 703 records · Page 39Linked to original sources
PubMed1991

Nerve growth factor inhibits immunoglobulin production by but not proliferation of human plasma cell lines.

The effects of nerve growth factor (NGF) on human plasma cells were studied. NGF inhibited immunoglobulin (Ig) production but not thymidine uptake by human plasma cell lines IM-9 and AF-10 in a dose-dependent fashion. This NGF-induced inhibition of Ig production was specific, since inhibition was blocked by anti-NGF serum but not by control serum. Interleukin (IL)-6 did not affect Ig production by IM-9 and AF-10; however, IL-6 restored NGF-induced inhibition of Ig production. NGF also inhibited Ig production (IgG, IgM, and IgA) without affecting thymidine uptake by PCA-1+ plasma cells generated in vitro. This inhibition was also blocked by anti-NGF serum but not by control serum and was restored by IL-6. These results suggest that NGF may interact with IL-6 in control of Ig production by plasma cells.

Cell Line↗
PubMed1991

Prognostic significant of indium-111 antimyosin antibody uptake in patients with dilated and hypertrophic cardiomyopathy.

The prognostic significance of myocardial uptake of indium-111 antimyosin was evaluated in 15 patients with idiopathic cardiomyopathy: 10 patients with dilated cardiomyopathy and 5 patients with hypertrophic cardiomyopathy. Seven of the 10 patients with dilated cardiomyopathy showed positive images; three of these 7 patients with strongly positive scans died within 3 months after scintigraphic examination. Four of the 5 patients with hypertrophic cardiomyopathy showed positive images; two of these patients with dilated left ventricle had prominent positive scans and higher heart to lung ratio. One of these two patients died 12 months after antimyosin scan. The heart to lung ratio of antimyosin uptake in total patients was correlated with left ventricular end-diastolic dimension (r = 0.51, P less than 0.05), end-systolic dimension (r = 0.57, P less than 0.05) and ejection fraction (r = -0.60, P less than 0.05) measured by echocardiography. Although the number of patients is small and the study is preliminary, indium-111 antimyosin antibody imaging could be of value in establishing prognosis of patients with dilated and hypertrophic cardiomyopathy, in selecting patients for cardiac transplantation, and in evaluating the effects of therapeutic interventions.

Adult↗
PubMed1991

Oscillatory potentials and permeability of the blood-retinal barrier in noninsulin-dependent diabetic patients without retinopathy.

Electroretinography and vitreous fluorophotometry were performed in 36 eyes of 36 noninsulin-dependent diabetic patients and in 32 eyes of 32 healthy control subjects between the ages of 30 and 59 years. Fluorescein fundus angiograms showed no abnormalities in either group. Peak implicit time of the first deflection of the oscillatory potential, interpeak interval between the first and second deflections, and the sum of the amplitudes of the upward deflections were analyzed. Inward permeability of the blood-retinal barrier was calculated by vitreous fluorophotometry and computer simulation. The peak implicit time of the first deflection and the interpeak interval between the first and second deflections of the oscillatory potential were significantly longer in diabetic patients than in control subjects (P less than 0.01). No significant difference in inward permeability of the blood-retinal barrier existed between the two groups. These results indicate that a selective delay in the peak implicit time of the oscillatory potential (neurosensory retinal abnormality) may be present in noninsulin-dependent diabetic patients, representing retinal functional changes before changes in blood-retinal barrier permeability are apparent.

Adult↗
PubMed1991

Alteration of serum lipoprotein metabolism by polychlorinated biphenyls and methionine in rats fed a soybean protein diet.

The effects of dietary supplementation of methionine to a 20% soybean protein isolate diet on serum lipoprotein profiles and secretion rate of VLDL in rats receiving polychlorinated biphenyls (PCB) were investigated. Serum cholesterol levels were higher in rats fed PCB or a methionine supplement than in controls. The effects of PCB and methionine were synergistic. The feeding of PCB resulted in more cholesterol in all fractions of serum lipoproteins tested, especially HDL (HDL1 and HDL2). Dietary supplementation of methionine primarily increased HDL cholesterol. The elevation of serum lipoprotein cholesterol due to PCB and/or methionine was significant in HDL1, which showed alpha-mobility. These results showed that methionine and PCB significantly influenced HDL metabolism. The secretion rate of VLDL was higher in rats fed PCB than in controls, but the addition of methionine to diets did not affect the secretion rate of VLDL cholesterol. This implies that PCB increased serum cholesterol partly through the stimulation of VLDL cholesterol secretion.

Administration, Oral↗
PubMed1991

Triiodothyronine administration affects urea synthesis in rats.

The purpose of the present study was to elucidate the mechanism by which thyroid hormone alters urea synthesis. The relative importance of urea cycle enzyme activities, substrate levels or the levels of urea cycle intermediates on urea production was investigated in a set of four experiments in which rats were fed a diet supplemented with 6-propyl-2-thiouracil (PTU, a thyroid inhibitor) and treated with triiodothyronine (T3). Compared with that of normal or control rats, the plasma level of T3 was significantly lower in rats fed a diet containing PTU only and elevated in rats given PTU + T3. Urinary excretion of urea and the liver content of ornithine in rats given PTU + T3 were significantly lower than in rats given PTU only. The liver level of ornithine was closely correlated to the excretion of urea in the present study. Fractional rates of protein synthesis in liver, kidney and small intestine were lower in the hypothyroid group. However, most free amino acid concentrations, except ornithine in liver and plasma and the activity of hepatic argininosuccinate synthetase (EC 6.3.4.5) of hypothyroid rats, were significantly reduced as compared with those of control or hyperthyroid rats. The results indicate that the increased hepatic ornithine content in the hypothyroid rats may be one of the regulatory factors causing changes in urea synthesis.

Administration, Oral↗
PubMed1991

Expression of a rat ovary-independent mammary tumor-associated antigen defined by a monoclonal antibody, TAK-B1.

A monoclonal antibody, TAK-B1, was produced by immunization of BALB/c mice with mammary carcinoma induced in inbred Sprague-Dawley rats by treatment with 7,12-dimethylbenz[a]anthracene. TAK-B1 reacted with ovary-independent mammary carcinoma cells which had been transformed from ovary-dependent mammary carcinoma cells, but did not react with original mammary carcinoma cells or with cells from mammary glands exhibiting fibrocystic changes or normal mammary glands. However, TAK-B1 reacted not only with basal cells of the epidermis and epithelial cells of the bottom portion of crypts of the small intestine in adult rats, but also with basal cells of epidermis in skin and mesenchymal cells around developing hair follicles in fetuses. We therefore classify TAK-B1 as an ovary-independent rat mammary tumor-associated antigen. Immunoelectron microscopic examinations revealed that the antigen recognized by TAK-B1 was localized in the cell surface membrane of ovary-independent mammary carcinoma cells. Immunoprecipitation assay revealed that the antigen recognized by TAK-B1 was composed of M 220,000 protein and four other minor proteins.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1991

Effect of recombinant human erythropoietin on human IgE production in vitro.

Recombinant human erythropoietin enhanced spontaneous IgE production (200-300% enhancement) in cultures of peripheral blood mononuclear cells (MNC) from atopic patients. In contrast, IgG and IgA production were only slightly enhanced (30-50% enhancement), and IgM production was not affected by erythropoietin. The enhancement of IgE production by erythropoietin was indirect since it required T cells and monocytes. However, erythropoietin effect was specific since enhancement was blocked by anti-erythropoietin antibody but not by control antibody. Interleukin-4 (IL-4) also enhanced spontaneous IgE production from atopic MNC. However, the enhancing effect by erythropoietin is different from that by IL-4, since the erythropoietin effect was not blocked by anti-IL-4 antibody, and conversely IL-4 effect was not blocked by anti-erythropoietin antibody. In contrast to the enhancing effect on atopic MNC, erythropoietin failed to induce IgE production in cultures of MNC from normal donors while IL-4 induced IgE production from normal MNC. However, when normal MNC were pre-incubated with IL-4, erythropoietin enhanced IgE production from IL-4-pre-incubated MNC. Moreover, B cells separated from IL-4-pre-incubated MNC produced IgE which was enhanced by erythropoietin. However, this effect required T cells and monocytes. These results indicate that erythropoietin could regulate ongoing IgE production in vitro by T cell- and monocyte-dependent mechanisms.

B-Lymphocytes↗
PubMed1991

Human recombinant erythropoietin directly stimulates B cell immunoglobulin production and proliferation in serum-free medium.

The effect of human recombinant erythropoietin (Epo) on B cell responses was studied in a serum-free medium. Epo enhanced IgM production and thymidine uptake by a human IgM-producing lymphoblastoid cell line, CBL. This effect was specific to Epo since enhancement was blocked by anti-Epo antibody but not by control antibody. Among the various cytokines, interleukin-4 (IL-4) enhanced IgM production and thymidine uptake while IL-6 enhanced IgM production without affecting thymidine uptake. In contrast, other cytokines including IL-1 beta, IL-2, IL-5, interferon-alpha (IFN-alpha), interferon-gamma (IFN-gamma), or granulocyte/macrophage colony-stimulating factor (GM-CSF) were without effect. However, the enhancing effect of Epo is different from that of IL-4 or IL-6, since Epo effect was not blocked by anti-IL-4 antibody or anti-IL-6 antibody. Moreover, specific binding of Epo was detected on CBL cells. Epo also enhanced immunoglobulin (IgG, IgM and IgA) production and thymidine uptake by purified tonsil small resting B cells stimulated by Staphylococcus aureus Cowan strain I (SAC) or by large activated B cells. In contrast, Epo had no effect on unstimulated small resting B cells. These results indicate that Epo could directly stimulate activated and differentiated B cells and could enhance B cell immunoglobulin production and proliferation.

Antibodies, Monoclonal↗
PubMed1991

von Recklinghausen's disease associated with somatostatin-rich duodenal carcinoid (somatostatinoma), medullary thyroid carcinoma and diffuse adrenal medullary hyperplasia.

This report describes the concomitant occurrence of a somatostatin-rich duodenal carcinoid, a medullary thyroid carcinoma and a diffuse adrenal medullary hyperplasia in a patient with von Recklinghausen's disease. A 50-year-old Japanese man died from lung metastasis of a malignant schwannoma. In addition to extensive viscero-cutaneous neurofibromatosis, two different types of neuroendocrine tumors were found in the duodenum and thyroid gland at autopsy. The duodenal tumor, which was located in the second portion, showed the histologic appearance of a carcinoid tumor with glandular differentiation and psammoma-bodies. Immunohistochemically the tumor cells were intensely positive for somatostatin. The thyroid tumor was composed of nests of tumor cells arranged in an endocrine pattern, and showed immunoreactivity for calcitonin. A review of the literature revealed no previously reported case of concomitant occurrence of duodenal somatostatinoma and medullary thyroid carcinoma in a single patient with von Recklinghausen's disease. Morphometric analysis of adrenal glands disclosed the presence of diffuse medullary hyperplasia. Thus, the present case exhibited a similarity in some respects with multiple endocrine neoplasia (MEN) syndrome, Type IIa or IIb.

Adrenal Gland Diseases↗
PubMed1991

Apocrine adenocarcinoma of the bilateral axillae.

A case of apocrine adenocarcinoma arising in the bilateral axillae is reported. The patient was an 88-year-old Japanese male who complained of a mass lesion and pus-like discharge in the right axilla. Another mass was also noticed in the left axilla. No other neoplastic lesion was found in other sites of the body. The histologic appearances of the bilateral axillary tumors were almost identical. Both were adenocarcinoma with varying degrees of differentiation, composed of glands and nests of atypical epithelial cells with abundant eosinophilic cytoplasm. Some neoplastic cells exhibited cytoplasmic projections on their apical surface. Foci of in situ carcinoma were observed within the neoplastic tissue in the bilateral axillae. The neoplastic cells were immunohistochemically positive for epithelial membrane antigen (EMA) and gross cystic disease fluid protein (GCDFP-15), but negative for carcinoembryonic antigen (CEA). On the basis of their histologic and immunohistochemical features and distinctive location, the tumors were diagnosed as apocrine adenocarcinoma.

Adenocarcinoma↗
PubMed1991

Significance of the methyl group on the oxazine ring of ofloxacin derivatives in the inhibition of bacterial and mammalian type II topoisomerases.

A study was made of the correlation between the in vitro inhibitory effects of several quinolones, including four ofloxacin derivatives, on bacterial DNA gyrase from Escherichia coli KL-16 and on topoisomerase II from fetal calf thymus. No correlation was observed between the inhibitions of DNA gyrase activity and topoisomerase II activity. On the other hand, the inhibitory effects of these quinolones against topoisomerase II were closely correlated with their inhibition of cell growth. Furthermore, among the oxazine derivatives tested, the derivative with a methyl group at position 3 in an S configuration showed the highest activity against DNA gyrase and derivatives without a methyl group on the oxazine ring were more potent against topoisomerase II than those with a methyl group. Among these derivatives, DR-3355, the S isomer of ofloxacin, showed the highest activity against DNA gyrase and low activity against topoisomerase II. These results indicate that the methyl group on the oxazine ring plays an important role in the inhibitory activities of ofloxacin derivatives for these enzymes.

Animals↗
PubMed1991

Clinicopathological findings of bucillamine-induced nephrotic syndrome in patients with rheumatoid arthritis.

This paper describes pathological and clinical investigations of glomerular lesions in bucillamine-induced nephropathy by analyzing biopsy materials from 9 patients with rheumatoid arthritis (RA). There was no specific predisposition for nephrotic syndrome induced by bucillamine in clinical profiles related to age, onset, duration of disease, sex, activity and dose of bucillamine. In light-microscopic, electron-microscopic and immunofluorescent findings, the characteristic changes were similar to those of idiopathic membranous glomerulonephritis (MGN). After discontinuance of bucillamine, the nephrotic syndrome improved slowly with or without corticosteroid therapy. Results confirmed that the most common lesion of nephrotic syndrome associated with bucillamine therapy in RA is MGN. We recommend that corticosteroid therapy should be restricted to cases with severe proteinuria.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1991

Onset of subacute aggravation of chronic thyroiditis followed immediately by transient hypothyroidism during antithyroid drug therapy for Graves' hyperthyroidism.

A 56-year-old man presented with clinical and biochemical hyperthyroidism with high thyroid 99mTc uptake, positive result for antimicrosomal antibody (MCHA; 1:8,100) and markedly high activities of thyrotropin-binding inhibitory immunoglobulin (TBII; 90.0%) and thyroid-stimulating antibody (TSAb; 2,400%). Fifty days after the initiation of antithyroid drug therapy, he developed a painful tender enlarged thyroid and an accelerated erythrocyte sedimentation rate (ESR), which were followed immediately by hypothyroidism with a transient increase in MCHA titer (peak; 1:218,700) despite of maintenance of high TBII and TSAb activities. Two and a half months after the recovery from hypothyroidism, recurrent hyperfunction was observed with further elevation of TSAb activity (4,643%). After about 2 weeks, recurrences of a painful tender enlarged thyroid and an accelerated ESR, which were followed by abrupt progression to hypothyroidism, were found. Specimens obtained when he had still slightly tender goiter after the first and second episodes of neck pain showed microscopically extremely extended interstitial fibrosis with collapsed follicles and moderate lymphocytic infiltration. Thyroid-stimulation-blocking antibody was not detected at either onset of hypothyroidism. Thus, it is possible that Graves' disease, subacute aggravation of chronic thyroiditis and hypothyroidism coexist in the same individual. In such patients, thyroid status may be determined by the degree of each of the stimulating factors (TSH, TSAb and/or unknown factors) and suppressive or destructive factors (humoral and/or cellular) and may be changed in a very short interval.

Autoantibodies↗
PubMed1991

Autoimmune thyroiditis with transient thyrotoxicosis: comparison between painful thyroiditis and painless thyroiditis.

Clinical and laboratory findings and long-term outcomes in 8 patients (7 women) with autoimmune thyroiditis (AT), aged 34-59 years, who had a painful tender goiter and a transient thyrotoxicosis with a low thyroid radioactive iodine uptake (RAIU), were compared with those in 15 patients (13 women) with painless thyroiditis (PT), aged 23-69 years. Six painful AT and 6 PT patients had a history of prior awareness of goiter. All patients with painful AT had a moderate or marked elevation of erythrocyte sedimentation rate and a positive result for C-reactive protein, while only 3 PT patients (group B) did. There were no significant differences between the mean age, duration of symptoms, white blood cell count, serum triiodothyronine (T3) and thyroxine (T4) concentrations, serum T3/T4 ratio and duration of thyrotoxicosis after the initial examination and prevalences of positive results for antithyroglobulin and -microsomal antibodies in the two diseases. Two of 8 painful AT patients showed a histologically chronic fibrous variant and 6 others showed chronic lymphocytic thyroiditis. All PT patients examined also showed lymphocytic thyroiditis. Two and 5 painful AT patients developed transient and persistent hypothyroidism, respectively, while 8 [7 in group A (normal ESR), 1 in group B] and 3 PT patients (1 in group A, 2 in group B) did, respectively. The mean serum thyroid-stimulating hormone level in the hypothyroid phase in painful AT patients was higher than that in PT patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

The 'oral 1,25-dihydroxyvitamin D3 pulse therapy' in hemodialysis patients with severe secondary hyperparathyroidism.

Many hemodialysis patients are still suffering from secondary hyperparathyroidism although 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) has been used to treat renal osteodystrophy for the last two decades. The main reason for its failure to correct the secondary hyperparathyroidism is that in patients, hypercalcemia occurs before adequate parathyroid hormone (PTH) suppression is obtained when a large daily dose of 1,25(OH)2D3 is started. In this study, the oral dose of 1,25(OH)2D3 (4.0 micrograms) was administered only twice a week at the end of hemodialysis ('oral 1,25(OH)2D3 pulse therapy'), in 19 patients with severe secondary hyperparathyroidism. Serum immunoreactive PTH started to decrease after 6 weeks of therapy, and the original level of 41.2 +/- 7.24 was reduced to 24.4 +/- 6.12 ng/ml by the end of the 6-month therapy (p less than 0.001). Serum alkaline phosphatase also was reduced by 64.4%. Three out of 19 patients suffered from hypercalcemia during the 4th month of therapy. Calcium supplement given to 6 other patients with severe secondary hyperparathyroidism did not lower serum PTH levels significantly after 6 weeks of therapy, although serum calcium levels increased and were sustained above 10 mg/dl for the last 5 weeks. These findings strongly suggest that the suppressive effect of the oral 1,25(OH)2D3 pulse therapy was attained by a direct action of 1,25(OH)2D3 on the parathyroid gland rather than by its ability to elevate serum calcium levels. In conclusion, the oral 1,25(OH)2D3 pulse therapy effectively lowered PTH levels in hemodialysis patients who cannot tolerate large daily doses of 1,25(OH)2D3.

Administration, Oral↗