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Biomedical subjects

K Satoh

Publications and source records attributed to K Satoh.

At least 469 records · Page 26Linked to original sources
PubMed1997

[Molecular diagnosis of post-transfusion GVHD using Y-chromosome specific sequences].

Graft-versus-host disease (GVHD) is one of the most serious complications of blood transfusion. Thus, it is important to make a correct diagnosis of post-transfusion GVHD as soon as possible in its onset. Presence of Y-chromosome positive donor lymphocytes in the peripheral blood of female GVHD patients is one of the direct evidences of lymphocyte chimerism, as well as shown by HLA chimerism. We have reported a rapid diagnosis technique of post-transfusion GVHD by polymerase chain reactions directed against Y-chromosome specific SRY gene. (Hayakawa S, et al: Transfusion. 1993, 33, 413-417). We can detect single male cell in 10,000 female cells by SRY directed nested PCR. Though this method is applicable only for the female GVHD cases involved with Y-chromosome positive male lymphocytes, it is possible to detect not only chimeric peripheral lymphocytes but also skin infiltrating donor lymphocytes.

Aged↗
PubMed1997

[Folliculogenesis and regulating factors].

Folliculogenesis and steroid production are the bases of fertility in the female mammal. Follicle stimulating hormones (FSH) plays an essential role in this process. It is clear that a variety of ovarian autocrine and paracrine factors can regulate this FSH receptor signal. In the past decade, it is established that growth factors, particularly insulin like growth factor and insulin like growth factor binding protein can modulate FSH receptor signal directly or indirectly. In addition to the folliculogenesis, it is possible that growth factors play a key role in follicle selection and atresia. With increased understanding of the intraovarian regulators in folliculogenesis, it becomes clear that several other autocrine paracrine factors may exist in intraovarian regulation of folliculogenesis, including steroid hormones, cytokines, inhibin, activin.

Animals↗
PubMed1997

[Case performed: simultaneous surgery for left coronary ostial stenosis and gastric cancer].

This report describes a case in which a 68-year-old male underwent two operations simultaneously for left coronary ostial stenosis and gastric cancer. Successfully performed procedures were a single coronary artery grafting with the saphenous vein to the left anterior descending artery, and a subtotal gastrectomy using the Billroth II method. The postoperative course was uneventful and the patient was discharged from the hospital in good condition after 42 days. At present, one-year postoperative, the patient has been visiting the outpatient clinic in healthy condition.

Aged↗
PubMed1997

Improvement of impaired glucose tolerance by oral administration of vanadyl sulfate by gavage in streptozotocin-induced diabetic rats.

We examined the effect of oral administration of vanadyl sulfate by gavage on the levels of blood glucose and plasma insulin during oral glucose tolerance test (OGTT) in diabetic rats. Diabetes was induced by intravenous injection of streptozotocin at the dose of 32 mg/kg. Nondiabetic control animals were injected with an equal volume of saline. Vanadyl sulfate at a dose of 25, 50, or 75 mg/kg was given orally by gavage for 2 weeks, starting 12 hours after streptozotocin injection. When vanadyl sulfate was given twice a day, half of the one-day-dosage was given in the morning and the remaining half in the evening. Glucose tolerance test with 5 g/kg of glucose was carried out 2 weeks after administration of vanadyl sulfate. The fasting the blood glucose level in the diabetic rats was higher than that in the non-diabetic rats, whereas the plasma insulin level in the diabetic rats was lower. An increase in blood glucose seen in the glucose tolerance test was significantly greater in the diabetic rats than in the non-diabetic rats. The level of plasma insulin was increased by glucose tolerance test in the non-diabetic rats, while it was not changed in diabetic rats. Oral administration of vanadyl sulfate by gavage significantly improved the impaired glucose tolerance in the the diabetic rats in a dose-dependent manner without any change in plasma insulin level. In conclusion, oral administration of vanadyl sulfate by gavage is effective on impaired glucose tolerance in streptozotocin-induced diabetic rats.

Animals↗
PubMed1997

[Extracorporeal membrane oxygenation for acute respiratory failure induced by Legionella pneumoniae. (Case report)].

We report a case of severe legionella pneumonia with acute respiratory failure, successfully managed with veno-venous extracorporeal membrane oxygenation (VV-ECMO). The patient presented with 4-day history of fever and cough. He was in critical condition, with exacerbated respiratory failure. Mechanical ventilation, volume replacement and antibiotic therapy were initiated. Despite increasing mechanical ventilatory support (FiO2 100%, TV 10 ml/kg, f 30/min, PEEP 5 cmH20), PaO2 fell below 40Torr and life sustaining measures were undertaken. VV-ECMO (flow 30 ml/kg/min) was commenced, and the patient responded well, with an elevation of PaO2. Erythromycin therapy was effective against the pneumonia. VV-ECMO was maintained for 92 hours, mechanical ventilation was successfully discontinued 11 days after and the patient was discharged 82 days after cessation of ventilator support. Serum antibody examination proved legionella infection. VV-ECMO may have a role in the management of patients with acute respiratory failure caused by bacterial pneumonia.

Acute Disease↗
PubMed1997

[Pulmonary thromboembolism associated with antiphospholipid syndrome in scleroderma].

A 51-year-old woman was referred to our hospital with dyspnea. Chest roentgenogram on admission showed dilation of the pulmonary arteries and hyperlucency in the lung fields. An ultrasonic cardiographic examination showed that the right atrium and ventricle were dilated. Pulmonary thromboembolism due to left popliteal vein thrombosis was diagnosed by perfusion scintigram of the lung, which showed multiple wedge-shaped defects, and by digital subtraction angiogram, which showed a filing defect in the left popliteal vein. Antiphospholipid syndrome was diagnosed after IgG anticardiolipin antibody was defected. Scleroderma was subsequently diagnosed because the patient exhibited Raynaud's phenomenon and proximal scleroderma. Although closely associated with lupus erythematosus and other lupus variants, antiphospholipid syndrome has not been recognized as a common complication of scleroderma. This is the first report of a patient with pulmonary thromboembolism associated with antiphospholipid syndrome and scleroderma.

Antibodies, Anticardiolipin↗
PubMed1997

Expression of nucleolar protein p120 in human lung cancer: difference in histological types as a marker for proliferation.

The function of proliferation-associated nucleolar protein p120 is unclear. A recent report that a yeast protein, NOP2, 67% homologous to human p120, is up-regulated during the onset of growth and influences the morphology of the nucleolus supports the notion that this protein could serve as a marker for proliferation in neoplastic cells. Lung cancer is characteristic in that different histological types show different biological features. We attempted to evaluate the levels of p120 expression in resected human lung cancer tissues of different histological types and the relation of p120 expression and cell proliferation using human lung cancer cell lines. When 37 frozen specimens of human lung cancer and normal lung were stained with a p120 monoclonal antibody, the nucleoli of cancer cells were positively stained, whereas a few macrophages in normal lung revealed only weak staining. The labeling index of p120 in squamous cell carcinoma (67.7 +/- 12.4%) was significantly higher than that in adenocarcinoma (35.3 +/- 12.6%) or in large cell carcinoma (30.1 +/- 17.3%; P < 0.01). In six human lung cancer cell lines and one normal lung fibroblast cell line cultured in vitro, there was a significant correlation between S-phase fraction and p120 mRNA (r = 0.851, P < 0.02)/p120 protein (r = 0.869, P < 0.01) or between doubling time and p120 protein (r = -0.928, P < 0.01). In the context of the reports that indicate higher [3H]thymidine incorporation and shorter doubling time in the squamous cell carcinoma, these results indicate that p120 can be a marker for proliferation in human lung cancer cells in vivo and in vitro, and that it has an important function in the cell cycle of tumor proliferation.

Adenocarcinoma↗
PubMed1996

Formation of 8-hydroxydeoxyguanosine in calf thymus DNA treated with tert-butylhydroquinone, a major metabolite of butylated hydroxyanisole.

Oxidative DNA damage caused by butylated hydroxyanisole (BHA), 2-tert-butyl(1,4)hydroquinone (TBHQ, a metabolite of BHA) and 2,5-di-tert-butyl(1,4)hydroquinone (DTBHQ), as well as 2,6-di-tert-butyl(1,4)benzoquinone (BHTQ, a metabolite of butylated hydroxytoluene), was evaluated by measuring the formation of 8-hydroxydeoxyguanosine (8OHdG) in calf thymus DNA. 8OHdG formation was greatly increased by TBHQ in a concentration-dependent manner. This effect was strongly enhanced by CuCl2 and suppressed by EDTA, bathocuproinedisulfonic acid disodium salt, methionine, glutathione reduced form or catalase, but was not affected by mannitol, sodium benzoate or sodium azide. Thus, TBHQ-induced 8OHdG formation may be mediated by copper. DTBHQ also induced the formation of 8OHdG, though to a much lesser extent than TBHQ, and its effect was stimulated by CuCl2. BHA had a small enhancing effect at high concentration, only in the presence of CuCl2, whereas in the case of BHTQ, it occurred both in the presence of CuCl2 and FeCl2.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1996

Differential activation of human platelets induced by Fc gamma receptor II cross-linking and by anti-CD9 monoclonal antibody.

Platelet activation induced by anti-CD9 mAb, which depends upon Fc gammaRII, has been considered to be similar to that induced by Fc gammaRII cross-linking. In this work, we present several lines of evidence to suggest that the mode of platelet activation induced by anti-CD9 mAb is distinct from that induced by Fc gammaRII cross-linking. Ca2+ release from intracellular Ca2+ stores induced by anti-CD9 mAb depended almost totally upon thromboxane A2 production and released ADP, whereas that induced by Fc gammaRII was affected only minimally by these factors. Fc gammaRII cross-linking induced Ca2+ channel opening, which is dependent upon the depletion of intracellular Ca2+ stores. In contrast, anti-CD9 mAb appeared to directly open Ca2+ channels, irrespective of intracellular Ca2+ stores (Kuroda et al., 1995. J. Immunol. 155: 4427). The Ca2+ requirement for the Ca2+ channels opened by Fc gammaRII cross-linking was also distinct from that induced by anti-CD9 mAb. The early phase of Fc gammaRII tyrosine phosphorylation was dependent upon thromboxane A2 production with anti-CD9 mAb-induced activation, whereas that of Fc gammaRII cross-linking was not. p72(syk) and p53/56(lyn) appeared to associate with Fc gammaRII in platelet activation induced by Fc gammaRII cross-linking, whereas there was little, if any, association between Fc gammaRII and these tyrosine kinases in anti-CD9 mAb-induced activation. Piceatannol, a selective inhibitor of p72(syk), enhanced Fc gammaRII tyrosine phosphorylation induced by Fc gammaRII cross-linking, whereas it attenuated the process in anti-CD9 mAb-induced platelet activation. It is suggested that the regulatory mechanism of Fc gammaRII tyrosine phosphorylation differs between these two modes of platelet activation.

Antibodies, Monoclonal↗
PubMed1996

Activation of protein-tyrosine kinase Syk in human platelets stimulated with lysophosphatidic acid or sphingosine 1-phosphate.

It has been reported that not only lysophosphatidic acid (LPA) but also its sphingolipid counterpart, sphingosine 1-phosphate (Sph-1-P), induce platelet functional responses. We report here Syk activation in human platelets stimulated with these lysophospholipids. LPA rapidly induced platelet protein-tyrosine phosphorylation, including that of Syk, and Syk activation, assessed by immunoprecipitation kinase assay. Sph-1-P, although rather weaker, mimicked LPA in inducing these tyrosine kinase-related events. Pretreatment of platelets with staurosporine, a potent protein kinase inhibitor, diminished LPA-induced Syk phosphorylation and activation, but not intracellular Ca2+ mobilization. These results demonstrate that, in platelets, the bioactive lysophospholipids induce Syk activation, which, however, may not be related to Ca2+ mobilization.

Blood Platelets↗
PubMed1996

Demonstration of a new dopamine-containing cell group in the primate rostral telencephalon.

The presence of dopaminergic neurons in the rostral forebrain has long been uncertain though the existence of tyrosine-hydroxylase (TH)-containing cells has been known in the region. Using an antibody to dopamine (DA), we demonstrated neurons immunoreactive (ir) to DA in the rostroventral striatum of the Japanese monkey (Macaca fuscata). The DA-ir cells were found at the ventral margin of the rostral part of the caudate nucleus, at the ventral margin of the rostral part of the nucleus accumbens, in the olfactory tubercle, and along the lateral margin of the putamen. These cells were intensely stained, small in size, and fusiform or ovoid in shape, and had one or two short processes. DA-ir cells were far smaller in number than TH-ir ones. The primates may possess a unique dopaminergic system in the rostral telencephalon.

Animals↗
PubMed1996

Chemoprevention of 4-nitroquinoline 1-oxide-induced rat oral carcinogenesis by the dietary flavonoids chalcone, 2-hydroxychalcone, and quercetin.

The modifying effects of dietary exposure of three flavonoids, chalcone, 2-hydroxychalcone, and quercetin, during the initiation and postinitiation phases of oral tumorigenesis initiated with 4-nitroquinoline-1-oxide (4-NQO) were investigated in male F344 rats. At 6 weeks of age, animals were divided into experimental and control groups. At 7 weeks of age, all animals except those treated with test chemicals alone and the untreated control group were given 4-NQO [20 parts/million (ppm)] in the drinking water for 8 weeks to induce oral neoplasms. For chemopreventive study by feeding of test compounds during the initiation phase, groups of animals were given diets containing 500 ppm chalcone, 500 ppm 2-hydroxychalcone, or 500 ppm quercetin for 10 weeks, starting 1 week before 4-NQO exposure. Seven days after stopping 4-NQO exposure, these groups were switched to the basal diet and kept on this diet until the end of the experiment. For chemopreventive study by treatment with test chemicals during the postinitiation phase, starting 1 week after the cessation of 4-NQO administration, the groups given 4-NQO and the basal diet were switched to the diets mixed with test chemicals and maintained on these diets for 22 weeks. The other groups consisted of rats fed diets containing 500 ppm test chemicals alone or of untreated rats. Thirty-two weeks after the start of the study, the incidence of tongue neoplasms and preneoplastic lesions, polyamine levels in the tongue epithelium, and cell proliferation activity estimated by bromodeoxyuridine labeling index were compared among the different dietary groups. Feeding of all test chemicals during either initiation or postinitiation phases caused a significant reduction in the frequency of tongue carcinoma (68-88% reduction; P < 0.05). Dietary administration of these test chemicals also significantly decreased the bromodeoxyuridine labeling index of the tongue squamous epithelium (P < 0.05). In addition, polyamine levels in the oral mucosa were lowered in rats treated with 4-NQO and test chemicals when compared to those given 4-NQO alone. These results indicate that the flavonoids chalcone, 2-hydroxychalcone, and quercetin present in our daily foods have an inhibitory effect on oral carcinogenesis initiated with 4-NQO, and such a modifying effect may be related partly to the suppression of cell proliferation.

4-Nitroquinoline-1-oxide↗
PubMed1996

Differential mobilization of tyrosine kinases in human platelets stimulated with thrombin or thrombin receptor agonist peptide.

Both thrombin and thrombin receptor agonist peptide (TRAP) activated p72syk and p60c-src with similar magnitudes. Both thrombin and TRAP induced translocation of p60c-src and p54/58lyn to cytoskeleton in an aggregation-dependent manner. Thrombin also induced cytoskeletal association of p72syk, but independent of platelet aggregation. Furthermore, p72syk associated with cytoskeleton underwent marked proteolysis, which was partially dependent upon calpain activation. In contrast, TRAP, even at concentrations as high as 100 mu M, did not induce p72syk translocation to cytoskeleton. Our findings suggest that cytoskeletal translocation of p72syk induced by thrombin is governed by a mechanism distinct from those of p60c-src and p54/58lyn translocation. It is also suggested that p72syk translocation induced by thrombin requires additional signal(s) other than that mediated by the recently-cloned thrombin receptor that couples with GTP-binding proteins and interacts with TRAP.

Blood Platelets↗
PubMed1996

Functional anatomy of GO/NO-GO discrimination and response selection--a PET study in man.

The purpose of this study was to identify the functional fields activated in relation to the NO-GO decision. Nine healthy subjects participated in the study which consisted of two test positron emission tomography (PET) scans (GO/NO-GO task and response selection task) and one control scan. In the response selection task, subjects were asked to flex their thumb of the right hand when a light emitting diode (LED) placed 60 cm from their eyes turned on red and to flex their index finger of the right hand when LED turned on green. In the GO/NO-GO task, subjects were asked to flex their thumb when the LED turned on red, however, they were asked not to move their fingers when LED turned on green. In the control state, they were asked simply to look at the LED without any movement of finger during the course of the scan. The mean regional cerebral blood flow (rCBF) change images for each task minus control and task minus task were calculated and fields of significant rCBF changes were identified. Several fields in the prefrontal cortex of the right hemisphere were specifically activated in relation to the GO/NO-GO task. The results indicate that the prefrontal cortex of the right hemisphere may be a key structure to make a decision not to move.

Adult↗
PubMed1996

Platelet-activating factor acetylhydrolase deficiency. A missense mutation near the active site of an anti-inflammatory phospholipase.

Deficiency of plasma platelet-activating factor (PAF) acetylhydrolase is an autosomal recessive syndrome that has been associated with severe asthma in Japanese children. Acquired deficiency has been described in several human diseases usually associated with severe inflammation. PAF acetylhydrolase catalyzes the degradation of PAF and related phospholipids, which have proinflammatory, allergic, and prothrombotic properties. Thus, a deficiency in the degradation of these lipids should increase the susceptibility to inflammatory and allergic disorders. Miwa et al. reported that PAF acetylhydrolase activity is absent in 4% of the Japanese population, which suggests that it could be a common factor in such disorders, but the molecular basis of the defect is unknown. We show that inherited deficiency of PAF acetylhydrolase is the result of a point mutation in exon 9 and that this mutation completely abolishes enzymatic activity. This mutation is the cause of the lack of enzymatic activity as expression in E. coli of a construct harboring the mutation results in an inactive protein. This mutation as a heterozygous trait is present in 27% in the Japanese population. This finding will allow rapid identification of subjects predisposed to severe asthma and other PAF-mediated disorders.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗
PubMed1996

Topographic representation in human intraparietal sulcus of reaching and saccade.

Regional cerebral blood flow was measured by positron emission tomography in seven subjects during reaching with saccade, reaching without saccade, saccade and control tasks. The reaching with saccade task activated two spatially distinct areas in the contralateral intraparietal sulcus (IPS) compared with the control condition. The area located in the anterior part of the IPS was also activated during the reaching without saccade but not during the saccade task. The other area, located in the posterior part of the IPS was, in contrast, active during the saccade but not the reaching without saccade task. The results indicate that the human IPS is functionally heterogeneous, and that functional roles of its anterior and posterior parts include control of reaching movements and eye movements, respectively.

Adolescent↗
PubMed1996

Binding of APC to the human homolog of the Drosophila discs large tumor suppressor protein.

The adenomatous polyposis coli gene (APC) is mutated in familial adenomatous polyposis and in sporadic colorectal tumors, and its product binds to the adherens junction protein beta-catenin. Overexpression of APC blocks cell cycle progression. The APC-beta-catenin complex was shown to bind to DLG, the human homolog of the Drosophila discs large tumor suppressor protein. This interaction required the carboxyl-terminal region of APC and the DLG homology repeat region of DLG. APC colocalized with DLG at the lateral cytoplasm in rat colon epithelial cells and at the synapse in cultured hippocampal neurons. These results suggest that the APC-DLG complex may participate in regulation of both cell cycle progression and neuronal function.

Adenomatous Polyposis Coli Protein↗