Biomedical subjects
Publications and source records attributed to T Takeuchi.
An unusual case of the signet-ring cell carcinoma of the bladder was reported. A 62-year-old Japanese male had a three-month history of intermittent, painless and gross hematuria. He was found to have a small egg-sized bladder tumor near the right ureteral orifice. A cytologic diagnosis of signet-ring cell carcinoma was made on a bladder washing and was confirmed by cytoscopic biopsy and surgical specimens.
Neonatal EEG, cerebral evoked potentials, CT scan findings and their evolution were investigated in 42 neonates who eventually developed the West syndrome. In infants with perinatal hypoxia, the EEG displayed most often marked or maximal depression in the first week of life. The highly abnormal initial EEG improved progressively with time. The most frequent findings in early infancy was discontinuous tracing and persistent alternating tracing at 1-2 months, and absent sigma rhythms at 3-4 months. The VEP, AEP and CT scan also showed findings suggesting severe degree of brain damage. In infants with meningitis, the initial EEG was less depressed but the EEG abnormality persisted or worsened. In infants with prenatal causes the neonatal EEG was variable, ranging from a normal background EEG to specific abnormalities. The evolution of paroxysmal abnormalities was similar in all groups. There were no epileptiform discharges in early months. The appearance of hypsarrhythmia was preceded by focal and then multifocal spike or sharp wave discharges.
In order to elucidate the effect of hyperglycemia on serum thyroid hormone levels, serum T4 and T3 concentrations were measured in rats with continuous intravenous glucose infusion. 30% glucose solution was infused into the left jugular vein at a rate of 1 ml/hr for 12 hr, and serum glucose level was maintained at 400 mg/dl. Serum T4 levels were slightly but not significantly decreased and serum T3 levels were significantly decreased by infusion of glucose for 12 hr. The ratio of serum T3 to T4 was not significantly changed in rats with glucose infusion. These results suggest an inhibitory effect of hyperglycemia on thyroid hormone release.
The present study was undertaken to determine the nature of the immunoregulatory T-cell defect after autologous mixed lymphocyte reaction (AMLR) activation in patients with systemic lupus erythematosus (SLE). Although AMLR was decreased in patients with SLE compared with normals, there was no difference in major proliferative cells (T4 cells and T4+JRA+ subset) in response to AMLR. Functional activity of AMLR-stimulated T4 subsets in patients with SLE and normals was examined in helper and suppressor/inducer assay, using pokeweed mitogen (PWM)-driven IgG synthesis. The T4+JRA- (helper) subset from SLE patients showed no greater activity than normals. However the T4+JRA+ (suppressor/inducer) subset from SLE patients showed decreased suppression induction compared with normals. This defect in the suppressor/inducer function was demonstrated even in patients with inactive SLR or in remission.
Some coat-color loci in mice are considered to control melanosome formation. In order to investigate genetic control of melanosome-associated proteins, we prepared monoclonal antibodies against mouse melanosomes. Melanosomes were isolated from B16 mouse melanoma through differential fractionation. BALB/c mice were immunized with an SDS-solubilized melanosome fraction. The spleen cells were subsequently fused with mouse myeloma cells, the resulting hybridomas cloned. Their secreted IgG was screened for reactivity to the SDS-solubilized melanosome fraction. One monoclonal antibody, M10, was shown to react to melanosomes by immunoelectronmicroscopy. It recognized a single protein band of 61,000 dalton on immunoblots of gel-fractionated melanosomes. The reactivities of M10 to skin homogenates from various coat-color mutants were examined by the ELISA method. Five congenic genotypes, non-agouti (a/a), brown (b/b), albino (c/c), dilute (d/d), and pink-eyed dilution (p/p) were examined. Among these, b/b and p/p showed significantly lower reactivities than a/a. Our results seem to suggest that the pigment abnormalities in these mutants result from abnormalities of the melanosomal proteins. In the case of albino mice, the reactivity of M10 to skin homogenate was almost the same as the wild-type mouse. It seems that the albino mice are capable of producing the melanosomal protein.
We evaluated involvement of adrenergic receptors in the responses of the hepatic vasculature to reduction either of portal venous flow or hepatic arterial inflow. Portal vein occlusion caused an increase in hepatic arterial blood flow (HAF) and decreases in hepatic arterial pressure (HAP) and hepatic arterial vascular resistance (HAR) in the intact group. After pretreatment with either yohimbine or prazosin, but not propranolol, occlusion of the portal vein produced a greater decrease in HAP as compared with that in the intact group. No significant changes in HAF, HAR, or hepatic tissue blood flow (HTF) occurred after the treatment. These results indicate that the compensatory response of the hepatic arterial vasculature to altered portal blood flow (PVF) is regulated independently of the intrahepatic adrenergic receptors. Hepatic arterial occlusion caused a significant decrease in portal venous pressure, PVF, and HTF. Portal venous vascular resistance (PVR) was reduced slightly, but not significantly. After pretreatment with either yohimbine or prazosin, but not propranolol, occlusion of the hepatic artery produced an opposite effect: to increase PVF and significantly decrease PVR. These results indicate that intrahepatic alpha-adrenoceptors participate in the regulation of portal vascular tone to maintain portal vein pressure at a steady level, when inflow from the hepatic artery is reduced.
The correlation between the delta and spindle components in compressed spectral array in 96 mentally retarded children (from 3 months to 12 years of age) was studied throughout nocturnal sleep. In 57 (59.4%, group A) of 96 subjects, periodic changes of delta and spindle rhythm powers were noted in sleep EEG. In 29 subjects (30.2% group B), delta but not spindle rhythm powers were found, and in the remaining 10 subjects (10.4%, group C) neither delta nor spindle rhythm powers were found throughout nocturnal sleep. A significant increase in abnormal clinical EEG was found in groups B and C as compared with group A. A significant decrease in the developmental quotient (DQ) was found in groups B and C as compared with group A. A significant decrease in DQ was also found in group C as compared with group B.
During treatment of primary cultured hepatocytes with dexamethasone for several hours, cyclic AMP formation and glycolysis by glucagon increased dose dependently. In the cells pretreated with dexamethasone, the output of intracellular cyclic AMP increased significantly (p less than 0.01) with glucagon of 2.8 X 10(-9) M or more, and the amount of glucose released also increased significantly (p less than 0.01) with glucagon of 2.8 X 10(-8) M or more, compared to the control cells. Moreover, treatment with dexamethasone increased the stimulatory effect of guanosine-5'-triphosphate (GTP), guanyl-5'-yl-imidodiphosphate on adenylate cyclase and significantly increased the stimulatory effect of fluoride. In the rat hepatocytes primarily cultured with dexamethasone for several hours, the stimulatory effect of GTP and fluoride on adenylate cyclase increased time dependently. These data indicate that the glucocorticoid regulates the sensitivity of adenylate cyclase at distinct loci of the postreceptor system.
Immunohistological studies of two testicular lymphomas are reported. In the first case, lymphoma cells bear T-cell markers such as Leu-4 and Leu-3a, while they do not react with antibodies against B-cell markers such as anti-Leu-14. In the second case, lymphoma cells do not react with anti-T or anti-B cell antibodies, but react with antibodies against B-4, OKT9, and C 13 (anti-HLA-DR). Thus, it is shown that the first case is a lymphoma of helper/inducer T-cell origin and the second case is a pre-B-cell or pre-pre-B-cell lymphoma.
The cell surface phenotype of peripheral blood lymphocytes (PBL) of systemic lupus erythematosus (SLE) patients was characterized with the anti-2H4 monoclonal antibody that defines the human suppressor inducer subset. The T4+2H4+ population of cells has been shown to be critical for the activation of T8+ suppressor cells. Patients with SLE has a markedly decreased percentage of T4+2H4+ cells (13 +/- 2%) in their PBL compared with normal controls (21 +/- 1%) (P less than 0.001). This reduction was greatest in patients with active SLE, especially those with renal disease. Serial analysis of patients with SLE and renal disease showed a correlation between percent positive circulating T4+2H4+ cells and disease activity. Moreover, there was a significant correlation between a low percentage of T4+2H4+ cells and decreased suppressor-inducer function in autologous mixed lymphocyte reaction-activated T4+ cells from SLE patients. Thus, a deficiency exists in SLE patients with active renal disease in the T4+2H4+ suppressor-inducer T cell subset.
Cells of TM10, an established cell line, are melanocytes that contain equal amounts of eumelanin (black pigment) and pheomelanin (yellow pigment). The content of pheomelanin drastically increased when the cells were cultured in growth medium containing 0.2mM-L-dopa (L-dihydroxyphenylalanine), which is the common precursor for both eumelanogenesis and pheomelanogenesis. After this treatment, the amount of pheomelanin was 3.7-fold greater than that of control in TM10, whereas the amount of eumelanin changed very little. In contrast, 5-S-cysteinyl-dopa, which is the specific precursor for pheomelanogenesis downstream of L-dopa, did not cause preferential increase in pheomelanogenesis. Ultrastructural observations also confirmed these results; in 0.2mM-L-dopa, an increase in the number of pheomelanosomes was observed in the cytoplasm of TM10 cells. Our results also suggest that the L-dopa treatment results in a decrease in tyrosinase activity per melanosome.
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Effects of arachidonic acid and mepacrine on ACh release from guinea-pig ileum myenteric plexus were investigated. Mepacrine (1-8 microM) inhibited the ACh release in a concentration-dependent manner. Arachidonic acid counteracted the inhibitory effect of mepacrine, but PGE2 did not. The inhibition induced by a combination of mepacrine and indomethacin on nicotine-induced ACh release was prevented by arachidonic acid, while that on spontaneous ACh release was prevented by arachidonic acid and PGE2 added simultaneously. The roles of arachidonic acid and PGs in the ACh release will be discussed.
A sandwich enzyme immunoassay (ELISA) system for mouse epidermal growth factor (EGF), which has a high sensitivity (500 fg/tube), has been established. It makes it possible to measure minute amounts of immunoreactive EGF in various mouse tissue without pretreatment. The immunoreactive EGF concentrations in digestive tissues of adult mice were much lower than previously reported. A significant sex difference was detected not only in the submandibular gland, but also in the oesophagus and forestomach. Although sialoadenectomy decreased the immunoreactive EGF contents in the alimentary tract to 4.2-23.8% of the pre-operative levels, the duodenal immunoreactive EGF was unaffected. Positive immunostaining was observed in the submandibular and sublingual gland, but not in the other digestive tissues, including the duodenum. These data implied that most of the EGF in the digestive tissues was derived mainly from the saliva and that a small amount of endogenous EGF existed in the duodenum. The physiological role of exogenous salivary EGF in the alimentary tract and the origin of endogenous duodenal EGF are discussed.
Approximately 20% of 52 Japanese males with invasive amebiasis confirmed by gel diffusion precipitin test (GDP) were positive by both Treponema pallidum hemagglutination test (TPHA) and nontreponemal antigen tests, and an additional 20% were positive by TPHA alone. However, none of 109 GDP-negative Japanese males without invasive amebiasis were positive on these serologic tests for syphilis. At least 2 bisexuals and 4 homosexuals were among those with invasive amebiasis. All of these biased males were positive on both TPHA and nontreponemal antigen tests. Four of the biased males had liver abscess and 2 had amebic dysentery or colitis. Bisexual or homosexual males were not found in the negative GDP group. These observations suggest that sexually transmitted amebiasis due to Entamoeba histolytica occurs among sexually biased males in Japan.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.