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T Sawada

Publications and source records attributed to T Sawada.

At least 361 records · Page 20Linked to original sources
PubMed1997

Predisposing factors to enlargement of spontaneous intracerebral hematoma.

BACKGROUND AND PURPOSE: Enlargement of intracerebral hemorrhage is a major cause of clinical deterioration. Identification of factors that predispose to hematoma enlargement is important in managing patients. METHODS: We selected 186 patients (71 women and 115 men; mean age, 64.8 +/- 12.5 years) with spontaneous intracerebral hemorrhage who had undergone an initial CT within 24 hours and a second scan within 120 hours of symptom onset. We compared patients with (n = 41) and without (n = 145) hematoma enlargement according to clinical characteristics and laboratory data. RESULTS: By multiple logistic regression analysis (n = 139), interaction of long interval (> 6 hours) from onset to first CT and small hematoma (< 25 cm3) strongly reduced risk of enlargement. The analysis also demonstrated that the following factors independently predisposed to enlargement: history of brain infarction; liver disease; interaction of fasting plasma glucose > or = 141 mg/dL and systolic blood pressure on admission > or = 200 mm Hg; and interaction of glycosylated hemoglobin A1c > or = 5.1% and systolic blood pressure on admission > or = 200 mm Hg. CONCLUSIONS: A patient examined > 6 hours after ictus who has a hematoma volume < 25 cm3 is unlikely to experience further hematoma growth. Prevention of brain infarction and premorbid management of liver disease may serve to lower the risk of hematoma enlargement. Although it remains controversial whether antihypertensive drugs should be used in the acute phase of intracerebral hemorrhage, poorly controlled diabetics with high systolic blood pressure (> or = 200 mm Hg) on admission also were at high risk of hematoma enlargement.

Aged↗
PubMed1997

Serial assessments of middle cerebral artery flow velocity with transcranial Doppler sonography in the recovery stage of eclampsia. A case report.

The pathophysiologic changes of eclampsia and/or hypertensive encephalopathy are unclear. Changes of middle cerebral artery flow velocity during the recovery stage in a case of eclampsia are reported. After the disappearance of signs and symptoms, the flow velocity began to increase, owing probably to delayed vasospasm, which was confirmed by magnetic resonance angiography. The vasospasm may be a consequence of eclampsia and may be of small significance in the pathogenesis.

Adult↗
PubMed1997

The effect of carnitine on ketogenesis in perfused livers from juvenile visceral steatosis mice with systemic carnitine deficiency.

Juvenile visceral steatosis (JVS) mice have been reported to have systemic carnitine deficiency, and the carnitine concentration in the liver of JVS mice was markedly lower than that of controls (11.6 +/- 2.6 versus 393.5 +/- 56.4 nmol/g of wet liver). To evaluate the role of carnitine in mitochondrial beta-oxidation in liver, we examined the effects of carnitine on ketogenesis in perfused liver from control and JVS mice. In control mice, ketogenesis was increased by the infusion of 0.3 mM oleate, but not by L-carnitine. In contrast, although ketogenesis in JVS mice was not increased by the infusion of oleate, it was increased 2.5-fold by the addition of 1000 microM L-carnitine. Addition of 50, 100, and 200 microM L-carnitine increased ketogenesis in a dose-dependent manner. The infusion of 0.3 mM octanoate or butyrate increased ketogenesis in a carnitine-independent fashion in both control and JVS mice. These findings suggest that endogenous long chain fatty acids from accumulated triglycerides may be used as substrates in the presence of carnitine in JVS mice. The relationship between ketogenesis and free carnitine concentration was examined in livers from JVS mice. Ketogenesis increased as free carnitine levels increased until concentrations exceeded about 100 nmol/g of wet liver (340 microM). The free carnitine concentration required for half-maximal ketone body production in liver of JVS mice was 45 microM (13 nmol/g of wet liver), which corresponds to a K(m) value of carnitine palmitoyltransferase I. We conclude that carnitine is a rate-limiting factor for beta-oxidation in liver only when the carnitine level in liver is very low.

Animals↗
PubMed1997

Norepinephrine stimulates mitogen-activated protein kinase activity in GT1-1 gonadotropin-releasing hormone neuronal cell lines.

The GT1-1 GnRH neuronal cell lines exhibit highly differentiated properties of GnRH neurons. We have used GT1-1 cells to study the roles of norepinephrine (NE), membrane depolarization, calcium influx, and phorbol esters in the regulation of mitogen-activated protein (MAP) kinase. NE, which is known to stimulate the release of GnRH, induced MAP kinase activity, the tyrosine phosphorylation of MAP kinase, and MAP kinase kinase activity. Forskolin led to activation of MAP kinase comparable with that induced by NE, and a selective inhibitor of cAMP-dependent protein kinase, H8, attenuated the NE-induced activation of MAP kinase. On the other hand, elimination of extracellular calcium by EGTA completely blocked NE-induced tyrosine phosphorylation of MAP kinase, and a selective inhibitor of calcium/calmodulin-dependent protein kinase, KN-62, attenuated the NE-induced activation of MAP kinase. Furthermore, depolarization of GT1-1 cells with 75 mM KCl, 10 microM BayK 8644, or 1 microM calcium ionophore (A23187) induced rapid tyrosine phosphorylation of MAP kinase. The omission of calcium from the extracellular medium completely abolished these effects of tyrosine phosphorylation of MAP kinase. Phorbol 12-myristate 13-acetate (PMA) also induced MAP kinase activity, but pretreatment of the cultured cells with PMA to down-regulate protein kinase C did not abolish the activation of MAP kinase by NE. In addition, although phosphorylation of Raf-1 kinase was stimulated by PMA, this phosphorylation was not induced by either NE or A23187. These results demonstrate that NE activates MAP kinase directly in GT1-1 cells, and that the effect of NE is mediated by increase in the cAMP level and by calcium influx, but not by PMA-sensitive protein kinase C or Raf-1 kinase.

Animals↗
PubMed1997

Protective efficacy of an affinity-purified hemolysin vaccine against experimental swine pleuropneumonia.

Protective efficacy of Actinobacillus pleuropneumoniae extracellular hemolytic toxins, RTX-toxin I (Apx I) and Apx II, was evaluated in pigs. The hemolysins were purified from culture supernatant of A. pleuropneumoniae strain HA-337, serotype 1 by immunoaffinity chromatography using a monoclonal antibody specific for Apx I or Apx II as ligand. Four pigs were vaccinated with the purified hemolysins absorbed on aluminum phosphate gel adjuvant. Four pigs of a control group were given placebo. Hemolysin-neutralizing antibodies were detected only in vaccinated group after booster injection. One of four control pigs died following an aerosol challenge with the homologous strain, and three surviving pigs developed serious clinical signs of pneumonia and had extensive lung lesions. In contrast, there was no mortality in vaccinated group. Only transient hyperthermia was observed in two vaccinated pigs after challenge. A necropsy, two vaccinated pigs had slight localized pulmonary lesions, though the remaining two had no lung lesions at all. These results indicate that the hemolysin vaccine made of Apx I and Apx II has good protective activity against swine pleuropneumonia caused by A. pleuropneumoniae serotype.

Actinobacillus Infections↗
PubMed1997

Morphological and flow cytofluorometrical analyses of regenerated rat thymus after irradiation.

Reconstituted rat thymuses were studied by immunohistochemistry, transmission electron microscopy (TEM) and flow cytofluorometry on days 0, 1, 2, 3, 5, and 7 after whole-body sublethal irradiation (6 Gy). One day after irradiation, numerous apoptotic cells were seen in the cortical thymus; the percentage of the sub-G1 peak representing apoptotic cells was 8.9% in the DNA content histogram of cytofluorometry. On day 3, the thymic structure had been destroyed and no distinction was drawn between the cortex and medulla. In this stage, few thymocytes but many macrophages were present, and the percentage of the sub-G1 peak reached a peak at 13.0%. Bromodeoxyuridine (BrdU) incorporated cells gradually increased after irradiation, and immunohistochemically numerous apoptotic cells were found primarily in the cortex on day 7. These thymocytes showed some levels of electron density of the nucleus as revealed by TEM. The percentage of S phase cells did not change markedly (20-30%) based on one-color DNA content histograms, but the percentage of early S and S phase cells was extremely high on day 7 (70%). These data indicate that a part of DNA synthetic cells may result in apoptosis. The combination of immunohistochemistry, TEM and flow cytofluorometry to analyze DNA content and BrdU incorporation proved a useful tool for investigating the reconstituted thymus.

Animals↗
PubMed1997

Discrimination of Listeria monocytogenes strains of serotype 4b by restriction enzyme analysis of chromosomal DNA.

Epidemiologically related cheese and environmental strains and epidemiologically unrelated strains of Listeria monocytogenes serotype 4b were examined by restriction enzyme analysis of chromosomal DNA with a total of 10 restriction enzymes. The DNA fingerprint patterns generated from each restriction enzyme digest of total DNA of all strains were classified. The restriction enzyme patterns of seven strains recovered from cheese and environmental samples in the same plant were identical to each other, but differed from those of seven epidemiologically unrelated strains. Two, originating from sporadic human patients, of eight epidemiologically unrelated strains exhibited the identical restriction enzyme patterns. Excepting these two strains, restriction enzyme analysis of the chromosomal DNA of L. monocytogenes serotype 4b can discriminate serologically indistinguishable strains.

Animals↗
PubMed1997

Role of upper gastrointestinal surveillance in patients with familial adenomatous polyposis.

Familial adenomatous polyposis (FAP) is an inherited autosomal-dominant disease in which hundreds and thousands of adenomas with malignant potential are found throughout the colon and rectum. An increased risk for benign and malignant upper gastrointestinal neoplasia has long been recognized in patients with FAP. In this article, the authors report their findings from a study of 35 registered patients to assess the prevalence, anatomic distribution, depth of invasion, and natural history of upper gastrointestinal tumors in patients with FAP.

Adenoma↗
PubMed1997

Analysis of allogenic lymphocytes in rat thymus following sublethal irradiation.

The effects of allogeneic lymphocytes on the rat thymus following sublethal irradiation were investigated using immunofluorescence. The recovery of thymus weight following irradiation was delayed in rats 6 days after receiving lymphocytes compared to controls. Allogeneic cells forming colonies were detected by immunofluorescence in both the cortex and medulla of the host thymus, most frequently on day 15 when an appropriate number (3 x 10(6)) was injected. The allogeneic cells detected in the host thymus, presumably T lymphocytes, appeared to disturb thymic reconstitution following irradiation. However, double-immunofluorescence staining revealed that allogeneic cells did not affect the thymic stromal microenvironment. Allogeneic cells may have subsequently affected thymic tissue via cytokines. It is important to investigate not only the character of allogeneic cells in the host thymus but also the interactions of donor allogeneic cells, host immature lymphocytes and thymic epithelial cells because of the possibility that these allogeneic cells in the host thymus could prevent the rejection of allogeneic transplants.

Animals↗
PubMed1997

Clinical global measures of dementia. Position paper from the International Working Group on Harmonization of Dementia Drug Guidelines.

Following is the report of the committee working on clinical global measures for antidementia drug guidelines. The concepts involved in global scales, the distinctions between change and severity scales, advantages and disadvantages of structured interviews, and anchoring of change scores are discussed, and selected existing clinical global scales are described. In addition, the committee assessed the utility of global scales in clinical trials for antidementia drugs. There was a consensus among the members of the working group on the following: (1) Clinical global scales are interview based; in most cases, they include information obtained from caregivers as well as directly from patients, but they can rely on information from the subject only. (2) Clinicians' global ratings are intended to assess clinically meaningful change based on multidimensional clinical assessment and take into account the clinical heterogeneity of dementia by assessing at least cognition, behavior, and functioning. (3) There are two distinct types of clinical global measures: (a) clinicians' interview-based global severity scales, which generally incorporate classification by stage or severity of illness and (b) clinicians' interview-based global change scales, which incorporate global assessment ratings of clinical change. The committee could not reach a consensus on whether global scales should be required in phase II and phase III clinical trials, or whether other specific assessments such as well-designed activities of daily living, cognition, and behavior measures could, when used in appropriate combinations, replace the global as assessments of clinical meaningfulness.

Activities of Daily Living↗
PubMed1997

[A case of multiple cerebral arterial thrombosis due to congenital protein C deficiency].

We report a 49-year-old man who had right hemiparesis and motor aphasia. A computed tomography revealed hypodense areas in the left frontal subcortex. A cerebral angiography demonstrated occlusion of the left distal internal carotid artery and both anterior cerebral arteries, as well as stenosis of the left internal carotid artery at the cervical portion. The second angiogram obtained a month later showed no changes. The diagnosis of atherothrombotic cerebral infarction was established on the basis of clinical profile and angiographic findings. Protein C activity and antigen levels were reduced to approximately one half of the normal level in the patient and his brother. The patient had no other risk factors for stroke. Protein C deficiency has been considered one of the risk factors for thrombotic diseases. Venous thrombosis is the most common clinical manifestation, whereas arterial thrombosis is relatively rare. It is generally believed that arterial ischemic stroke associated with protein C deficiency occurs with embolic mechanism, and atherothrombotic infarction is extremely rare. This is the first report suggesting the possibility that protein C deficiency can cause cerebral thrombosis.

Cerebral Angiography↗
PubMed1997

Immuno-histochemical demonstration of alpha-tubulin distribution in rat incisor ameloblasts after vinblastine administration.

This study used the immunoperoxidase method to demonstrate post-vinblastine-administration distribution of alpha-tubulin, a structural component of the microtubule, in rat incisor secretory-stage and maturation-stage ameloblasts. Immunostaining for alpha-tubulin in secretory-stage ameloblasts and maturation-stage ameloblasts decreased from 1 hr to 6 hrs after vinblastine administration. At 12 to 24 hrs after administration, it appeared to begin recovering from the distal region of the cytoplasm toward the proximal side of the cytoplasm and, by 48 hrs after administration, had almost reached control levels. In both stages, ameloblast cell shapes and organelle polarities changed concurrently after the decrease in alpha-tubulin staining.

Ameloblasts↗
PubMed1996

MAGE-1 and MAGE-3 or -6 expression in neuroblastoma-related pediatric solid tumors.

MAGE-1 and MAGE-3 or -6 are genes encoding melanoma-rejection antigens recognized by cytotoxic T lymphocytes in an HLA-A1 restriction manner. MAGE-1 and MAGE-3 or -6 were expressed in 5/14 (36%) and 6/14 (43%) neuroblastoma (NB) cell lines, and in 20/41 (49%) and 24/41 (59%) clinical NB-related tumors, respectively. Additionally, they were also expressed in pediatric tumors of other types such as rhabdomyosarcoma and Wilms' tumor. MAGE-1 expression at a functional level in tumor cells was confirmed by the cytotoxicity assay using MAGE-1-specific tumor-infiltrating lymphocytes (TIL). In clinical NB-related tumors, MAGE-3 or -6 expression demonstrated an inverse correlation to clinical stage. Furthermore, although the sample number was small, the incidence of MAGE-1 and/or MAGE-3 or -6 expression was significantly correlated to the absence of metastasis and a more favorable clinical outcome (p < 0.05). These results may suggest that NB cells silent for the expression of MAGE genes escape from the host anti-tumor immune response and consequently retain a growth advantage. Finally, NB-related tumors could be reliable candidates for immunotherapy targeted towards MAGE gene products.

Antigens, Neoplasm↗
PubMed1996

Ultrasensitive heterogeneous immunoassay using photothermal deflection spectroscopy. 2. Quantitation of ultratrace carcinoembryonic antigen in human sera.

We previously proposed a photothermal immunoassay based on highly sensitive detection by a photothermal beam deflection method using colloidal gold as a labeling material. The assay system was significantly improved in terms of background reduction of ultrasensitive laser spectrometry through the newly designed reaction and separation procedure using microspheres for a solid phase. Highly sensitive laser spectrometric analysis is often susceptible to interference by even a small amount of admixtures. In this subsequent study, we improved our photothermal immunoassay so that it possesses further selectivity, matching that of the highly sensitive photothermal detection method. It was proved that our method could be applied to determine ultratrace quantities of a carcinoembryonic antigen (CEA) in cancer patients' and normal sera. The lower detection limit of CEA was 0.078 ng/mL (9.8 amol, absolute quantity). This is 10 times superior to that of any other immunoassay method and has enough detectability to measure a low level of CEA in healthy individuals. Intraassay coefficient of variation is about 8% at eight different concentrations (n = 6). We assayed 61 serum samples, and there was a good correlation between this method and previously established ELISA. We obtained clearer demarcation of healthy persons and colon cancer patients in terms of the CEA value than was obtained by ELISA. We believe this is the first report in which the laser-based ultrasensitive immunoassay is proved to be applicable to human sera, although the matrix admixtures causing interference in the assay were quite different in each sample serum.

Carcinoembryonic Antigen↗
PubMed1996

Prognostic significance of T antigen expression in patients with gastric carcinoma.

BACKGROUND: Thomsen-Freidenreich (T) antigen, the immediate precursor antigen of the human blood MN system, has been detected in malignant cells, but not in most normal cells in which it is cryptic but can be unmasked by desialylation. In this study, we determined the prognostic significance of T antigen in specimens with gastric carcinoma. METHODS: Expression of T antigen was studied immunohistochemically in 157 gastric carcinoma tissue specimens obtained at surgery from the First Department of Surgery, Osaka City University Medical School between 1983 and 1987. RESULTS: T antigen expression was detected in 72 of the tumors (45.9%). The staining pattern was inclined to change from a luminal surface type to a cytoplasmic type in accordance with decreasing degree of cell differentiation. The rate of expression of T antigen significantly increased (P < 0.05) with serosal invasion, and was significantly higher (P < 0.01) in patients with hepatic or lymph node metastasis or peritoneal dissemination than in those without such metastasis or dissemination. Furthermore, among patients with Stage III or IV disease, those with T antigen-positive tumors had a significantly poorer prognosis than those with T antigen-negative tumors. CONCLUSIONS: Our findings suggest that relationships exist between expression of T antigen and depth of invasion, hepatic metastasis, lymph node metastasis, or peritoneal dissemination, and that T antigen may be a good indicator of the prognosis of patients with gastric carcinoma.

Antigens, Neoplasm↗