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Biomedical subjects

A Ueda

Publications and source records attributed to A Ueda.

At least 181 records · Page 10Linked to original sources

Electron-microscopic studies on the presence of gap junctions between corneal fibroblasts in rabbits.

Corneal fibroblasts, major cellular components of the corneal stroma, are loosely arrayed between collagen lamellae. They play an important role in the metabolic and physiological homeostasis mechanisms by which the cornea is kept transparent. This paper deals with the demonstration of the gap junctions between the corneal fibroblasts of rabbits by transmission electron microscopy of thin sections and of freeze-fracture specimens. Under the transmission electron microscope, the corneal fibroblasts are seen between the lamellae of collagen fibers of the corneal stroma. Their long cytoplasmic processes are in contact with those of neighboring fibroblasts. Typical gap junctions are found between these cytoplasmic processes. In the freeze-fracture images, intramembrane particles with a diameter of 10.3 nm form polygonal aggregates on P faces. These findings suggest that corneal fibroblasts, coupled with each other, might function synchronously through gap junctions responsible for metabolic activities essential for the maintenance of corneal transparency.

Animals↗

Uptake of india ink particles and latex beads by corneal fibroblasts.

The fate of India ink particles and polystyrene latex beads injected into the corneal stroma of rabbits was studied by the naked eye, light microscopy, and electron microscopy. All the injected ink particles or latex beads were unchanged in shape, size, and number for at least 6 months. India ink particles and latex beads were endocytosed by the corneal fibroblasts within 3-4 days after injection. Numerous ink particles were packed into vacuoles, 0.5-10 micron in diameter, which occupy a large volume of the cytoplasm of the cell body and processes of fibroblasts in and near the injected area. Each latex bead, 0.72 micron in diameter, is usually enclosed in one vesicle, and a large number of vesicles are distributed throughout the cytoplasm. In corneal tissue removed 10 min after injection of India ink and cultured for 3 or 7 days, uptake of many ink particles by the fibroblasts was seen. By this experiment, the contribution of the blood-derived cells was completely excluded, and it is more distinctly shown that the corneal fibroblast has a strong endocytotic activity. The uptake and long-term storage of ink particles and latex beads by the corneal fibroblast are reactions that protect the organ without inflammation from the injury and harm by non-toxic foreign materials.

Animals↗

The Leu-1 B-cell subpopulation in patients with rheumatoid arthritis.

Ly-1-B cells have been shown to be elevated in autoimmune mice, especially NZB, and to secrete IgM autoantibody, suggesting that Ly-1 B cells may participate in autoimmune diseases. In this study, B-cell populations carrying Leu-1, a human T-cell surface molecule homologous to mouse Ly-1 (Leu-1 B), were examined by dual fluorescence flow cytometry, in peripheral blood lymphocytes taken from patients suffering from various autoimmune disease. These B cells were shown to be present at a significantly high percentage in rheumatoid arthritis (RA) patients. There was no significant correlation among the incidence of Leu-1 B cells, rheumatoid factor (RF) titers, and the amount of IgM production in vitro. There was, however, a significantly high incidence of Leu-1 B cells in RA patients with a high RF titer (greater than 5 X 2(13), suggesting that these B cells in RA may play an important role in IgM RF production in vivo.

Antigens, Differentiation, B-Lymphocyte↗

Serum concentration of placental proteins (PP5 and PP10) in toxemia of pregnancy as related to intrauterine growth retardation.

Maternal serum concentrations of placental proteins 5 (PP5) and 10 (PP10) were measured by radioimmunoassay in 568 samples obtained from 308 healthy pregnant women and 63 women having toxemia of pregnancy. Below-normal PP5 values were more widely distributed in the mild than in the severe toxemia group, while the incidence of above-normal PP5 values was found only in the severe toxemia group. The incidence of below-normal PP10 values was higher in the severe than in the mild toxemia group. Our study thus suggests that simultaneous measurement of PP5 and PP10 concentrations in maternal serum in toxemia of pregnancy is a useful monitoring technique for predicting progressive pathological change and placental dysfunction related to IUGR.

Female↗

Prevalence rates and risk factors for allergic symptoms among inhabitants in rural districts.

In order to determine the prevalence of allergic disorders and their association with agricultural factors, a total of 3,717 inhabitants of rural districts in Kumamoto Prefecture were ashed to fill out a questionnaire concerning their allergic status. The results obtained were as follows: One or more items of allergic symptoms were reported by 44% of the subjects. The prevalence rate of each symptom was 8% for respiratory organs, 5% for delayed type of respiratory disorders, 10% for nasal mucosa, 16% for eyes, 16% for urticaria-like derma and 26% for eczema-like derma. Twenty-one percent of the subjects had past histories of allergic diseases such as asthma (3%), nasal allergy (3%), urticaria (6%), contact dermatitis (9%) and so forth. These allergic conditions were seen to be more common among farmers than non-agricultural workers, and also among subjects with allergic constitution than those without such constitution. The highest (62%) prevalence of allergic symptoms was observed in farmers engaged in poultry raising, followed by those engaged in raising flowers (58%), tobacco (58%), cortinellus shiitake (55%), cucumber in plastic greenhouse (53%) and mandarin orange (53%). Among the symptomatic subjects, 12-38% of those with each symptom gave farm work as the direct causative factor for developing the corresponding symptom. Pesticide spraying was the most common agent among those factors.

Adult↗

Synthesis and biological properties of two dimeric forms of human alpha-atrial natriuretic peptide.

Two dimeric forms of human alpha-atrial natriuretic peptide (alpha-ANP) were synthesized by solution methods and compared with monomeric alpha-ANP in terms of some biological and immunochemical properties. The parallel form (beta'-ANP) and the antiparallel form (beta-ANP) were equipotent in smooth muscle relaxant activity in isolated rat aorta and their ED50 values were estimated to be 1.7 X 10(-8) M and 1.6 X 10(-8) M, respectively. Diuretic and natriuretic responses induced by beta-ANP and beta'-ANP anesthetized rats were equally less potent but exhibited a significantly longer duration than those induced by alpha-ANP. beta-ANP and beta'-ANP possessed immunoreactivities of 60-100% and 50-90% (alpha-ANP, 100% on a molar basis), respectively, with three different antisera raised against alpha-ANP-related peptides.

Animals↗

A comparative histopathological, immunological, and biochemical study of experimental intravenous paracoccidioidomycosis induced in mice by three Paracoccidioides brasiliensis isolates.

We carried out a comparative study of the histopathology (lung, liver, spleen, kidney and adrenals) and the anti-P. brasiliensis humoral (immunodiffusion test) and cellular (footpad test) immune response of mice intravenously inoculated with yeast forms of three P. brasiliensis isolates (Pb 18, Pb 192, Pb 265). Pb 265 (avirulent strain) did not evoke specific lesions or antibody production; the levels of cellular immunity were significantly lower than those of the two other isolates. Lung granulomas induced by strain Pb 18 were richer in fungi and neutrophils and poorer in mononuclear cells when compared to those induced by strain Pb 192. Extrapulmonary lesions were more frequent in mice infected with strain Pb 18. Strains Pb 18 and Pb 192 raised similar humoral and cellular anti-P. brasiliensis responses. Cell wall analysis did not suggest striking differences among the strains. Slightly higher levels of the water soluble fraction 3 (which contains the immunogenic galactomannan and protein) were detected in strain Pb 265.

Animals↗

Mechanisms for improvement of cardiac performance by nifedipine in an acute mitral regurgitation in dogs.

To elucidate the mechanisms of the beneficial hemodynamic action of nifedipine in congestive heart failure, the systolic and diastolic hemodynamic parameters were evaluated for 30 min after sublingual administration of 20 mg of nifedipine in 12 dogs with acute mitral regurgitation (group 1) and in 5 dogs without mitral regurgitation (group 2, sham operation group). An additional 6 dogs with mitral regurgitation were followed for 30 min without nifedipine (group 3). Nifedipine lowered both arterial pressure and systemic vascular resistance, increased coronary blood flow and stroke volume significantly in both groups 1 and 2. The left ventricular developed tension was increased by nifedipine only in group 1, probably due to the geometric changes in the expanded left ventricle in failure, secondary to left ventricular preload and afterload reduction. Nifedipine had no effects on ventricular relaxation properties in this study. This study suggests that the mechanisms responsible for the improvement of cardiac performance induced by nifedipine in heart failure caused by an acute mitral regurgitation are essentially a reduction in left ventricular afterload and an increase in left ventricular contractility secondary to afterload reduction.

Animals↗

A multiple regression analysis of hemoglobin values and iron status in Japanese farmers.

The authors performed multiple regression analysis of hemoglobin values and the parameters related to iron dynamics. The subjects consisted of 37 farmers whose Hb, Ht, GB, SI, %-St, SFR and FEP was examined once a month for one year. 19.2% of the female farmers had anemia of which 73.8% was iron-deficiency anemia, 13.7% being latent iron deficiency. Hb, GB and FEP in males and SI, %-St, SFR, FEP in females revealed clear seasonal variations. Multiple correlation coefficient between Hb and SI, %-St, SFR, FEP as independent variables was significant in females but not in males, and the ratio of contribution (38.7%) was not very high, however, the multiple correlation coefficient was significantly high (0.622). Standard regression coefficients between Hb and SFR, FEP were significantly high (p less than 0.01). When Ht and GB were added to these 4 variables, multiple correlation coefficients (male, 0.906; female, 0.957) were remarkably high, which means serum-related variables such as Ht and GB have an undeniably important role as explanatory variables of hemoglobin levels. These standard regression coefficients showed seasonal changes.

Adult↗

Concentrations and isotope ratios of carbon, nitrogen and sulfur in ocean-floor basalts.

Fresh submarine basalt glasses from Galapagos Ridge, FAMOUS area, Cayman Trough and Kilauea east rift contain 22 to 160 ppm carbon and 0.3 to 2.8 ppm nitrogen, respectively, as the sums of dissolved species and vesicle-filling gases (CO2 and N2). The large range of variation in carbon content is due to combined effect of depth-dependency of the solubility of carbon in basalt melt and varying extents of vapour loss during magma emplacement as well as in sample crushing. The isotopic ratios of indigenous carbon and nitrogen are in very narrow ranges, -6.2 +/- 0.2% relative to PDB and +0.2 +/- 0.6% relative to atmospheric nitrogen, respectively. In basalt samples from Juan de Fuca Ridge, however, isotopically light carbon (delta 13 C = around -24%) predominates over the indigenous carbon; no indigenous heavy carbon was found. Except for Galapagos Ridge samples, these ocean-floor basalts contain 670 to 1100 ppm sulfur, averaging 810 ppm in the form of both sulfide and sulfate, whereas basalts from Galapagos Ridge are higher in both sulfur (1490 and 1570 ppm) and iron (11.08% total iron as FeO). the delta 34S values average +0.3 +/- 0.5% with average fractionation factor between sulfate and sulfide of +7.4 +/- 1.6%. The sulfate/sulfide ratios tend to increase with increasing water content of basalt, probably because the oxygen fugacity increases with increasing water content in basalt melt.

Carbon↗

Hemoglobin values in adult women of various occupational groups in the community.

In 1966 and 1971, the authors studied hemoglobin values of about 2,000 women of 10 different occupational groups and different social classes in the same district. The mean values of hemoglobin and serum iron were highest in nursing students followed by urban housewives and nutritionists and lowest in 3 groups of farm wives and shoe factory laborers. The difference in the mean values of hemoglobin observed among occupational groups was in principle assumed to be due to the difference of frequency in levels of 11-12 g/dl. Hemoglobin levels between 1966 and 1971 tended to improve as a whole and the differences among occupational groups have been reduced. In this study, some kinds of social conditions as well as some physiological factors related to hemoglobin values were investigated. In the same occupational group, unmarried women had a higher level of hemoglobin than married women. Further, married women with infants showed a relatively lower level than those with no infants. This suggests that hemoglobin values of female workers may be significantly influenced not only by work conditions but also by social conditions including family circumstances.

Adult↗

A follow-up study on the lung disorders of rush (igusa) farmers exposed to "sendo" dust.

In the process of "tatami" mat production, from cultivating to weaving, rush farmers are exposed to "sendo" (dyer's earth) dust using it to prevent fading of the "tatami" mat color. It has been found that the workers tend to develop a relatively early stage of pneumoconiosis after about 20 years of this work. In 1980, 51 male (58.6 years old) and 37 female (54.4 years old) rush farmers, some of whom were previously examined in 1970, were re-examined for lung disorders. Chest X rays in the 1980 showed, 49.0% of males and 62.2% of females over 1/0 according to the 12 point profusion scale with irregular small opacities being dominant, a significant increase in the prevalence rates of pneumoconiosis compared with 1970 values (p less than 0.01 for both males and females). A relatively high prevalence of respiratory complaints and/or lung function impairment was also found. However, there were no severe cases and no significant changes were seen to have occurred during the seventies by those tests. It was also observed that increases in lung disorders during the decade were more common in the female workers. These findings suggest that the pathogenesis of rush farmer's pneumoconiosis might be in the histological changes of bronchial and/or alveolar walls by the deposition of "sendo" dust. The present study revealed that the lung disorders in the rush farmers may be associated with long-term inhalation of "sendo" dust, and the introduction of more suitable dust control measures in that processing must be actively pursued in the near future.

Adult↗

A case of adult T-cell leukemia initiated with central nervous system symptoms.

We treated a 52-year-old Japanese woman with adult T-cell leukemia (ATL) initiated with central nervous system (CNS) symptoms. Her chief complaints were paraplegia and left facial palsy. CNS-ATL was diagnosed because of the following three features. 1) Various sized lymphoid cells with marked nuclear convolution were numerous in her cerebrospinal fluid. 2) These cells were a monoclonal proliferation of T lymphocytes with OKT 4 marker. 3) The patient's serum was positive for anti-ATL associated antigen (ATLA). Although the neurological signs and symptoms improved markedly after intrathecal administration of combined chemotherapy (methotrexate, cytarabine and corticosteroid), these ATL cells were highly resistant to radiation therapy. The abdominal mass which developed in the course of the disease was diagnosed as a tumor formed of ATL cells, and VEPA (vincristine, endoxan, prednisolone and adriamycin) was administered with marked success.

Antigens, Neoplasm↗

Determination of the second component of complement (C2) by electroimmunoassay in sera from patients with systemic lupus erythematosus.

The concentration of C2 was determined by electroimmunoassay in sera from healthy controls, patients with systemic lupus erythematosus (SLE), their relatives and patients with other diseases. Monospecific anti-human C2 serum was obtained by immunizing rabbits with purified human C2 and then absorbing the rabbit serum with inactivated normal human serum that was made insoluble. In addition, it was shown that human C2 could be purified by means of affinity chromatography on anti-C2 antibody coupled Sepharose. The serum concentration of C2 was 37.8 +/- 5.0 (s.d.) micrograms/ml in healthy controls (n = 133). In patients with SLE, the values were below normal in the active phase and were within normal limits in the inactive phase, showing good correlations with other complement parameters such as CH50, C4, C3 and factor B. C2 concentration was well correlated with C2 haemolytic activity in the inactive phase of SLE, but there was no relationship between the two in the active phase. The mean value of C2 concentration in the relatives of patients with SLE showed no significant difference from that in healthy controls. C2 concentration tended to be high in patients with scleroderma, polymyositis, rheumatoid arthritis, Behçet's disease and aortitis syndrome. However, the values were often low in patients with chronic liver diseases, suggesting a decrease of C2 production in the liver.

Chromatography, Affinity↗