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Biomedical subjects

Y Ueda

Publications and source records attributed to Y Ueda.

At least 973 records · Page 54Linked to original sources
PubMed1985

Abnormalities in autologous mixed lymphocyte reaction-activated immunologic processes in systemic lupus erythematosus and their possible correction by interleukin 2.

The autologous mixed lymphocyte reaction (AMLR) represents the activation, proliferation and differentiation of T cells in response to signals from autologous non-T cells. Upon stimulation by autologous non-T cells, OKT4+ cells produce interleukin 2 (IL2); cells contained within both OKT4+ and OKT8+ cell populations can also be activated by autologous non-T cells to become sensitive to IL2. Once these activated OKT4+ and OKT8+ cells are exposed to IL2 produced by OKT4+ cells, they will proliferate and go on to differentiate into effector cells. Patients with systemic lupus erythematosus (SLE) have a defect in the AMLR. The ability of OKT4+ cells to produce IL2 in the AMLR is impaired. Upon triggering with autologous non-T cells, their OKT8+ cells become sensitive to proliferative signals of IL2; however, their OKT4+ cells fail to express IL2 receptors. These defects are a consistent feature in patients with SLE. AMLR-induced immunologic processes which require cell interactions between OKT4+ cell subpopulations are not correctable even by the addition of normal IL2. However, the immunologic processes mediated through OKT4+-OKT8+ cell interactions can be corrected with normal IL2. The latter finding suggests that the partial correction of the AMLR-induced immunologic processes with IL2 might lead to suppressed B cell hyperactivity of patients with SLE.

Adult↗
PubMed1985

The interaction of hemoglobin O Arab with Hb S and beta+ thalassemia among Israeli Arabs.

We have studied 105 individuals in the village of Jasser El Zarka in the Northern Coast of Israel of whom 59% had at least one abnormal hemoglobin. Of the individuals studied 41% were AA, 13.3% AS, 28.6% AOArab, 10.5% SOArab, 0.9% SS, 38% OArab-beta + Thal, and 1.9% beta Thal trait. The SOArab double heterozygotes were characterized by a normal mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC), and an increase of Hb F (11.7 +/- 4.3%) and 2,3-diphosphoglycerate levels (27.8 microns/g Hb). The increase of Hb F is higher than the one seen among OArabs of other ethnic backgrounds. Their clinical course was moderately severe and osteoporosis was quite frequent. The interactions of Hb OArab and Hb S were studied in vitro and it was confirmed the Hb OArab lowers the minimal gelling concentration of mixtures with Hb S (as compared to mixtures of Hb S and Hb A), but that this effect is ionic-strength dependent. Our data are in conflict with previous claims that Hb OArab mixtures with Hb S polymerized almost as much as pure S. Oxygen association curves show a significant displacement of the p50 to the right, but the effect of oxygen dissociation is less apparent. The displacement was not nearly as significant as with SS cells, confirming our gelation data. Blood group determinations establish that these Arab populations had black African admixture. The Hb OArab/beta + Thal double heterozygotes exhibit moderate anemia (10.3 g% of Hb) and the percentage of Hb A was 17.2 +/- 1.8%. The fetal Hb was 5.4 +/- 2.1% and the 2,3-diphosphoglycerate level in two cases was 17.4 mumol/g Hb. The only case of a homozygote SS had moderate anemia (10.3g Hb%), 25.7% of Hb F, and a very benign course.

Adolescent↗
PubMed1985

Oculopotency of embryonic quail pineals as revealed by cell culture studies.

Pineal bodies from 8-day-old quail embryos were dissociated and cultured in order to examine their potency for differentiation under in vitro conditions. Polygonal pigment cells and lentoid bodies started to differentiate after about 2 and 4 weeks, respectively. Lentoid bodies were shown immunologically to contain all classes of crystallins. The results indicate that embryonic pineal cells of avian species retain 'oculopotency' to differentiate into several types of ocular cells.

Animals↗
PubMed1985

Distribution, ontogeny and projections of cholecystokinin-8, vasoactive intestinal polypeptide and gamma-aminobutyrate-containing neuron systems in the rat spinal cord: an immunohistochemical analysis.

The distribution, ontogeny and fiber projections of cholecystokinin-8, vasoactive intestinal polypeptide and gamma-aminobutyrate-containing neuronal systems in the rat spinal cord were investigated by means of immunocytochemistry. Immunoreactive fibers to cholecystokinin-8, vasoactive intestinal polypeptide and glutamate decarboxylase (gamma-aminobutyrate-synthesizing enzyme, used as a marker of gamma-aminobutyrate) were widely distributed in the spinal cord, being particularly concentrated in the superficial dorsal horn, suggesting a close relationship to the pain transmission system. Cholecystokinin-8-containing neurons were mostly distributed in the dorsal laminae and glutamate decarboxylase-containing neurons were distributed in both the dorsal and ventral horns. Vasoactive intestinal polypeptide-containing neurons were detected in the lateral spinal nucleus and the lamina X. Cholecystokinin-8 and vasoactive intestinal polypeptide immunoreactive structures first appeared on gestational day 17-18. Although no substantial change in immunoreactive structures was observed during the fetal period, they increased markedly after birth. On the other hand, glutamate decarboxylase-positive structures appeared at gestational day 16 and those in the grey matter reached a maximum content at birth; both groups were present in adult animals. Transection of the upper cervical cord resulted in accumulations of cholecystokinin-8 and glutamate decarboxylase rostral to the lesion, revealing the presence of supraspinal projections of cholecystokinin-8 and glutamate decarboxylase to the spinal cord. The same experimental procedure demonstrated the existence of vasoactive intestinal polypeptide-mediating neuronal projections to the supraspinal level, as the accumulating fibers occurred in the area caudal to the lesion.

Animals↗
PubMed1985

Carcinoma of the pancreas with endocrine component in childhood. A case report.

A case of pancreatic tumor in a six-year-old girl is presented. The tumor had histologic characteristics of acinar cell carcinoma with endocrine component. Grossly, it was encapsulated and attached to the tail of the pancreas, measuring 8 cm in the greatest diameter. Histologically, the tumor was composed of medium-sized tumor cells, with mild pleomorphism showing mainly acinar structures. Many of these tumor cell contained fine granules that were periodic acid-Schiff positive, diastase resistant, and positive with dimethylaminobenzaldehyde nitrite strain for tryptophan, and some contained granules that were positive with Grimelius stain and positive with peroxidase-antiperoxidase technic for gastrin. Electron microscopy revealed two types of membrane-bound granules in the tumor cells. The larger granules measured 400-700 nm in diameter and appeared to be zymogen granules, while the smaller ones measured 100-200 nm in diameter and appeared to be neuroendocrine granules. Some cells contained both granules. The postoperative course of the patient was excellent, and she was alive and well 13 years after operation. This may be the second reported case of acinar-endocrine cell tumor of the pancreas.

Carcinoma↗
PubMed1985

Angiographically occult angiomas: a report of thirteen cases with analysis of the cases documented in the literature.

Thirteen cases of angiographically occult angioma (AOA) are reported. Nine of these presented with intraparenchymatous hemorrhage, and the other 4 patients had epilepsy. The pathological diagnosis was arteriovenous malformation in 12 cases and cavernous angioma in 1. All surgical specimens but 2 contained hemosiderin pigment. In addition to these 13 cases, we reviewed 159 cases of AOA reported in the literature and analyzed them in terms of age, sex, symptoms and signs at admission, computed tomographic findings, location and size of angioma, history of previous and recurrent hemorrhage, type of hemorrhage, and outcome of operation to determine the characteristics of AOAs. The results of these analyses are described in detail, and the indications for surgical treatment of suspected AOAs are discussed. Our microsurgical technique for detecting the angioma within or adjacent to the hematoma is also presented.

Adolescent↗
PubMed1985

Epicardial cyst. Report of a case with successful resection.

As a result of mass-screening, a 7-year-old girl was noted to have an abnormal shadow and was subsequently diagnosed as having a pericardial cyst. During surgery, we discovered that the cyst originated from the epicardium, and only its free wall was resected with the cyst left open to the pericardial cavity. The postoperative course was uneventful. This is presumed to be the first case of epicardial cyst ever reported in Japan. In diagnosing the epicardial cyst, the use of chest films, echocardiography and computed tomography assist angiography in making a differential diagnosis from intracardiac lesion. In treatment, surgical resection is advised. Even though the cyst may be asymptomatic, the possible compression on the surrounding organs and possible rupture into the pericardial cavity must be avoided.

Child↗
PubMed1985

Quadricuspid aortic valve associated with severe aortic regurgitation.

A 57-year old man with severe aortic regurgitation was found to have a quadricuspid aortic valve. Aortic valve replacement was performed successfully with a St. Jude Medical prosthetic valve. On histological examination, the resected cusps showed fibrotic thickening with calcification.

Aortic Valve↗
PubMed1985

Studies on the ontogenesis and the regulatory mechanisms of placental lactogen and insulin binding sites (receptor) in rat liver.

The ontogenesis of specific binding of 125I-hPL and 125I-insulin was determined in rat liver cell membranes (10(5) X g pellets), and the regulatory mechanisms of these binding sites were also examined. There were striking differences in the mode of ontogenesis between binding sites of hPL and insulin in rats. HPL binding sites were very few in liver cell membranes from fetal and immature rats. They began to increase after puberty, and markedly increased in late pregnancy. On the other hand, insulin binding sites, which decreased in late pregnancy, were dominant in fetal liver and placenta. Consequently, the lipolytic and glycogenolytic activities of hPL in maternal liver were accentuated, whereas the effects of insulin on maternal liver were suppressed. In contrast, in fetal liver and placenta only the anabolic effects of insulin seemed conspicuous. According to the results of experiments on in vivo administration of estradiol-17 beta, progesterone, hydrocortisone or hPL to intact or hypox-rats, and the measurement of serum rat chorionic mammotropin (rCM), rPRL, estradiol-17 beta, and insulin during pregnancy in rats, the increase in hepatic hPL binding sites observed in late pregnancy might be, at least in part, due to rCM secreted from placenta, and the decrease in insulin binding sites due to the increase in serum insulin itself in rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

[Cerebral blood flow measured by Xenon enhanced CT in brain tumors].

In the management of malignant brain tumors, it is important to know the extent and viability of tumors. However, an ordinary CT scan with iodine enhancement has only a limited ability to distinguish the tumor from surrounding normal tissue. Since the blood flow in tumor tissue was found to be relatively high in a previous experimental report, we have investigated the blood flow in a tumor and the surrounding brain. The Xenon enhanced CT method has several advantages over the conventional isotope method and enables us to evaluate rCBF with the same resolving power as with the CT scan. We evaluated rCBF in 15 brain tumor cases and obtained the following results. Mean rCBF value of the tumor is a little lower than that of gray matter and higher than that of surrounding edema. Our Xe-CT method enables us to distinguish the demarcation between the tumor area and the surrounding edematous area and offers useful information for determining the extent of resection in surgery. Mean lambda value of the tumor which is not obtainable in vivo by radionuclide scanning, was 1.02 +/- 0.06 for gliomas and 0.72 +/- 0.09 for metastatic tumors. rCBF value and lambda value are important elements to know the uptake rate of anticancer drugs into the brain tumors. And to evaluate these value in each brain tumor is useful in the selection of chemotherapeutic agents.

Adult↗