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Biomedical subjects

A Sato

Publications and source records attributed to A Sato.

At least 289 records · Page 16Linked to original sources
PubMed1998

Unusual variant of left paraduodenal hernia herniated into the mesocolic fossa leading to jejunal strangulation.

Paraduodenal hernia is a rare condition in which the small bowel loops are herniated into an unusual fossa in the periduodenal area. We treated a patient with paraduodenal hernia diagnosed preoperatively. A 28-year-old woman was admitted to our hospital because of intermittent abdominal pain. Abdominal ultrasonography revealed a large tumor adjacent to the pancreas. Provisional diagnosis made according to computed tomography (CT) findings was tumor of the pancreas tail. However, on a CT scan performed after the administration of diatrizoate meglumine/diatrizoate sodium (Gastrografin, Schering, Berlin, Germany) the mass was shown as a jejunum loop located between the stomach and the pancreas body. Subsequent laparotomy revealed that the jejunum loop was herniated into an unusually large mesocolic fossa and that the hernial orifice was covered by the adhesion between the transverse and descending colons. It seemed that the small intestine within the mesocolic fossa was strangulated by this adhesion. The patient's abdominal pain resolved postoperatively. These observations suggest that paraduodenal hernia should be suspected in patients with chronic, atypical abdominal pain, regardless of the findings for small bowel obstruction.

Adult↗
PubMed1998

Lipoprotein disorder in brain infarction and hemorrhage.

The cholesterol, triglyceride, and apolipoprotein B content of very low-, intermediate-, low-, and high-density lipoprotein fractions (separated by ultracentrifugation) and plasma were measured in healthy controls and patients with atherothrombotic infarction (26), lacunar infarction (26), and brain hemorrhage (14). In both atherothrombotic and lacunar infarction, increased plasma and low-density lipoprotein apolipoprotein B and a decreased low-density lipoprotein cholesterol/apolipoprotein B ratio were noted. In brain hemorrhage patients, a decreased ratio was also observed. These findings suggest that increased small dense low-density lipoprotein is a characteristic risk factor for atherothrombotic and lacunar infarction.

Adult↗
PubMed1998

Dysgerminoma with syncytiotrophoblastic giant cells arising from 46,XX pure gonadal dysgenesis.

BACKGROUND: Dysgerminoma with syncytiotrophblastic giant cells is a rare ovarian tumor. Only ten cases of this tumor have been reported, and all tumors developed in normal ovaries. This report presents a case of dysgerminoma with syncytiotrophoblastic giant cells arising in a patient with 46,XX pure gonadal dysgenesis. CASE: An 18-year-old phenotypic female of normal height without somatic anomalies with nonfunctional ovaries underwent a bilateral gonadectomy for a right ovarian tumor and left streak gonad. The tumor revealed a dysgerminoma containing scattered syncytiotrophoblastic giant cells. Her serum hCG was elevated, and hCG was demonstrated within syncytiotrophoblastic giant cells immunohistochemically. The clinical diagnosis was stage Ia dysgerminoma with syncytiotrophoblastic giant cells. Her karyotype was 46,XX and the sex-determining region Y gene was not detected in tumor DNA by polymerase chain reaction analysis. CONCLUSION: This rare gonadal tumor may arise from dysgenetic gonads in addition to gonadoblastoma and pure dysgerminoma. It is an example of tumorgenesis in pure gonadal dysgenesis with no identifiable Y chromosome component.

Adolescent↗
PubMed1998

Nahocols and isonahocols, endothelin antagonists from the brown alga, Sargassum autumnale.

Novel endothelin antagonists, nahocols A, A1, B, C, D1 and D2, and isonahocols D1 and D2, were isolated from the brown alga, Sargassum autumnale. Their structures were determined through detailed analysis of NMR spectra and chemical reactions. Nahocols have an aryl prenyl ether structure, which are speculated to be biogenetic precursors of the ubiquitous prenyl hydroquinones or prenyl benzoquinones in the plant and animal kingdoms.

Endothelin-1↗
PubMed1998

Establishment of a novel cell line (TS-2) of pre-B acute lymphoblastic leukemia with a t(1;19) not involving the E2A gene.

The t(1;19)(q23;p13) translocation involving the E2A gene on chromosome 19p13.3 is a nonrandom translocation that is often seen in childhood pre-B-cell acute lymphoblastic leukemia (ALL). However, recent studies have demonstrated the presence of immunophenotypic and molecular heterogeneity among patients with the cytogenetically identical chromosome translocation. Here we report a novel pre-B ALL cell line, TS-2, with t(1;19) translocation not involving the E2A gene. The breakpoint of t(1;19) in TS-2 was demonstrated to be at 19p13.3, a region indistinguishable from the locus of the E2A gene, by cytogenetic study and fluorescence in situ hybridization. However, rearrangement of the E2A gene was not detected in TS-2 by Southern blot analysis. Moreover, the expressions of PBX1 or E2A/PBX1 fusion genes were not detected by an extensive study with Northern blot analysis and reverse transcription-polymerase chain reaction. These findings suggest that TS-2 may have a genetic abnormality involving uncharacterized gene(s) at 19p13.3 distinct from the E2A gene and, therefore, may be useful for investigating the heterogeneity of molecular pathogenesis in leukemias with t(1;19)(q23;p13) translocation.

Adenovirus E2 Proteins↗
PubMed1998

An IDDM patient who complained of chest oppression with ischemic changes on ECG in insulin-induced hypoglycemia.

A 34-year-old female IDDM patient complained of chest oppression in hypoglycemic episodes and electrocardiograms revealed reversible ischemic changes occurring concomitantly with hypoglycemia. The ECG changes improved and the chest oppression disappeared following increasing blood glucose level by glucose intake. Master's double load test and treadmill load test were positive for ischemic changes. Radioisotopic myocardial scintigraphy by thallium and BMIPP did not show any filling defects and coronary angiography revealed no remarked stenosis in the coronary arteries. She had no mitochondrial tRNA(Leu) (A-->G) gene mutation at nucleotide position 3243, but both the patient and her mother had a G-to-A transition within the replication origin of the light strand at nucleotide position 5744 of the mitochondrial gene. As the patient's maternal family had no history of ischemic heart disease, it is not clear whether mitochondrial gene mutation at nucleotide position 5744 reflects the occurrence of cardiac ischemia. Some disorders of microcirculation in capillary vessels in cardiac muscles may occur in such patients.

Adult↗
PubMed1998

Onset age-dependent variations of three islet specific autoantibodies in Japanese IDDM patients.

The age related incidence rate of insulin-dependent diabetes mellitus shows a bimodal distribution, not only in Caucasians but also in Japanese. To evaluate the onset age-related autoimmune profile at presentation in insulin-dependent diabetes mellitus (IDDM), glutamic acid decarboxylase (GAD) autoantibody, islet cell antibody (ICA), and insulin autoantibody (IAA) were measured in 137 newly diagnosed Japanese IDDM patients with onset ages between 0-29 years. The prevalence of GAD autoantibody was significantly increased from the lowest (32%) in the 0-5 years onset age group to 75% in the 13-19 years onset age group (P < 0.05), whereas the IAA prevalence significantly decreased from the peak (48%) in the 6-12 years onset age group to 10% in the 20-29 years onset age group (P < 0.05). The ICA prevalence was increased from the lowest (32%) in the 0-5 years onset age group to the highest (53%) in the 20-29 years onset age group similar to that for the GAD autoantibody. Such results demonstrate that there was age-related autoimmune characteristics at presentation of IDDM in Japanese as well as in Caucasians.

Adolescent↗
PubMed1998

Dietary carbohydrate intake plays an important role in preventing alcoholic fatty liver in the rat.

BACKGROUND/AIMS: Dietary carbohydrate intake during ethanol ingestion augments the induction of hepatic cytochrome P450 2E1 (CYP2E1) by ethanol. This study addresses the role of carbohydrate intake in the development of alcoholic fatty liver in the rat. METHODS: Male Sprague-Dawley rats were pair-fed on liquid diets containing ethanol (3.5 g/day, 36% of total calories) with different amounts of carbohydrate and fat for 4 weeks, and the development of fatty liver was observed biochemically and morphologically. RESULTS: An ethanol-containing low-carbohydrate diet (protein 17%; fat 36%; carbohydrate 11%; ethanol 36%) had more markedly adverse effects on the liver of rats than did an isocaloric ethanol-containing high-carbohydrate diet (protein 17%; fat 5%; carbohydrate 42%; ethanol 36%). The hepatic triglyceride level in the rats that consumed the low-carbohydrate diet was higher than that in the rats kept on the high-carbohydrate diet, a finding that was confirmed histologically. The ethanol-containing low-carbohydrate diet caused a marked increase in the activity of hepatic CYP2E1. The CYP2E1 protein level, as measured by Western blot analysis, matched the activity of CYP2E1, as measured by the rates of dimethylnitrosamine, p-nitrophenol and ethanol metabolism. The severity of the fatty liver was well correlated with the increased CYP2E1 activity. CONCLUSIONS: Dietary carbohydrate intake plays an important role in the development of alcoholic fatty liver by affecting CYP2E1 activity in the liver. A liquid diet containing ethanol in which the ethanol is included at the expense of fat is more acceptable to rats than a diet in which the ethanol replaces carbohydrate.

Animals↗
PubMed1998

Clinorotation reduces number, but not size, of cartilaginous nodules formed in micromass cultures of mouse limbbud cells.

In previous studies we used a ground based model to investigate the cellular responses to microgravity by exposing micromass cultures of embryonic limb cells to simulated weightlessness on a clinostat. Cultures set up in T-flasks and rotated at 30 rpm showed that clinostatted cultures had less chondrocyte differentiation than stationary or rotation controls, as assessed by number of nodules/culture stained with cartilage specific Alcian blue. In the current study, nodule size and shape of these nodules was assessed by interactive measurement of area, perimeter, circularity, and equivalent diameters, using the Optimas imaging software. Results show no significant difference in any of the measurements, indicating that clinorotation has no effect on expansion of the nodules either by differentiation of cells within the nodule, or by recruitment of cells into the nodule. The reduction in number of nodules without an alteration in size and shape indicates that the effect of simulated microgravity is to reduce the cell interactions required for the initial condensation of cells into a nodule, probably by interference with cell adhesion molecules.

Animals↗
PubMed1998

A novel evaluation system of metastatic potential of oral squamous cell carcinoma according to the histopathological and histochemical grading.

We established a new evaluation system for metastatic potential of oral squamous cell carcinoma (SCC), utilizing a combined examination of histopathological grades of the carcinomas based on cell differentiation and invasive mode according to Yamamoto's criteria, and the cellular expressions of CD44, E-cadherin (E-cad), heparan sulfate glycosaminoglycan (HS-GAG) and Phaseolus vulgaris leukoagglutinin (L-PHA)-binding oligosaccharides on the carcinomas. Histochemical patterns of expression of these markers were classified into positive (+2), weakly positive (+), and negative (-). The histopathological grades and the histochemical patterns of the SCC were estimated on a 0-2 point scale, i.e. point 2 for poorly differentiated, mode 4D, CD44++, E-cad-, HS-GAG++, or L-PHA++; point 1 for moderately differentiated, mode 4C, CD44+, E-cad+, HS-GAG+, or L-PHA+; and point 0 for well differentiated, mode 1, mode 2, mode 3, CD44-, E-cad++, HS-GAG-, or L-PHA-. As a result, incidence of metastasis in the cases with a total score of more than 6 (62.8%) was significantly higher than that with a total score of less than 5 (9.3%). This evaluation system will yield useful information concerning the prognosis of patients with oral SCC.

Biomarkers, Tumor↗
PubMed1998

Cytotoxic scalarane sesterterpenes from a sponge, Hyrtios erecta.

Novel scalarane sesterterpenes (1-4) were isolated from a sponge, Hyrtios erecta (order Dictyoceratida). They were characterized by means of spectral analyses, X-ray crystallography, and chemical reactions. Compound 1 showed potent in vitro and in vivo antitumor activities. In addition, the structure-activity relationship was also discussed using computer-assisted structure matching of 1 and aragusterols.

Animals↗
PubMed1998

Suppression of aggregate formation and apoptosis by transglutaminase inhibitors in cells expressing truncated DRPLA protein with an expanded polyglutamine stretch.

To elucidate the molecular mechanisms whereby expanded polyglutamine stretches elicit a gain of toxic function, we expressed full-length and truncated DRPLA (dentatorubral-pallidoluysian atrophy) cDNAs with or without expanded CAG repeats in COS-7 cells. We found that truncated DRPLA proteins containing an expanded polyglutamine stretch form filamentous peri- and intranuclear aggregates and undergo apoptosis. The apoptotic cell death was partially suppressed by the transglutaminase inhibitors cystamine and monodansyl cadaverine (but not putrescine), suggesting involvement of a transglutaminase reaction and providing a potential basis for the development of therapeutic measures for CAG-repeat expansion diseases.

Animals↗
PubMed1998

Increased type 2 cytokine expression by both CD4+ CD45RO+ T cells and CD8+ CD45RO+ T cells in blood circulation is associated with high serum IgE but not with atopic dermatitis.

Type 2 cytokines, such as interleukin-4 (IL-4) and IL-13, are associated with immunoglobulin E (IgE) production. This association has also been observed in CD8+ T cells from patients infected with leprosy and human immunodeficiency virus (HIV). Using intracellular cytokine staining and flow cytometry, the cytokine profile [IL-2, IL-4, IL-10, IL-13, and interferon (IFN)-gamma] of both CD4+ and CD8+ memory/effector T cells circulating in atopic dermatitis (AD) patients was investigated at the single cell level. The levels of type 2 cytokines in CD4+ T cells or CD8+ T cells in AD patients with high levels of serum IgE (AD-H), low levels of serum IgE (AD-L), and healthy controls were compared. Increased production of IL-4 and IL-13 in both CD4+ CD45RO+ T cells and CD8+ CD45RO+ T cells after 4 h in vitro stimulation with phorbol 12-myristate 13-acetate and ionomycin, was more prominent in AD-H patients than in AD-L patients or healthy controls, whereas IFN-gamma-producing CD4+ CD45RO+ T cells and CD8+ CD45RO+ T cells were relatively diminished in AD-H patients. CD4+ T cells and CD8 + T cells from AD-H patients, cultured for 48 h with phorbol 12-myristate 13-acetate and ionomycin, released larger amounts of IL-4 and IL-13 but smaller amounts of IFN-gamma than both types of cells from AD-L patients or healthy controls. In addition, when stimulated with immobilized anti-CD3 monoclonal antibody (MoAb) and anti-CD28 MoAb, CD4+ CD45RO+ T cells and CD8+ CD45RO+ T cells from AD-H patients contained more IL-4-producing cells but fewer IFN-gamma-producing cells compared with healthy controls. Finally, spontaneous mRNA expression of IL-4 in blood CD8+ CD45RO+ T cells isolated from AD-H patients was increased, as determined by reverse transcriptase-polymerase chain reaction. Therefore, in AD patients with high IgE levels, type 2 cytokine (IL-4 and IL-13) expression is associated with IgE production, in both CD4+ CD45RO+ T cell and CD8+ CD45RO+ T cell subsets.

Adolescent↗
PubMed1998

A simple procedure for the isolation of rat kidney lysosomes.

BACKGROUND: A procedure for the isolation of highly purified lysosomes from normal rat kidney is described. METHODS: The method depends on the swelling of mitochondria when the postnuclear supernatant fraction is incubated with 2 mM Ca2+. The lysosomes can then be separated from the swollen mitochondria by Percoll density gradient centrifugation. RESULTS: The lysosomal fraction obtained by our method was enriched more than 30-fold in terms of marker enzymes with a yield of about 11%. Electron microscopic examination and the measurement of the activities of marker enzymes for various subcellular organelles indicated that our lysosomal preparation was essentially free from contamination by other organelles. CONCLUSION: We believe that this procedure for isolating kidney lysosome will be useful in the study of the mechanisms of specific modification, processing and catabolism of proteins.

Albumins↗
PubMed1998

Structural determination of metabolites of S-1153, a new, potent, non-nucleoside, anti-HIV agent in rat liver microsomes.

1. S-1153, a non-nucleoside agent that is under development in the USA as a new anti-HIV agent, has potent antiviral activity based on the inhibition of reverse transcriptase. 2. S-1153 was incubated with rat liver microsomes and NADPH, and seven metabolites were formed. The main metabolites were identified as the S-oxide, N-oxide and sulphone of S-1153. 3. Two other minor metabolites were assumed to be S-1153 hydroxylated on the isopropyl moiety. 4. Our findings confirmed the existence of at least three oxidative metabolic pathways of S-1153.

Animals↗
PubMed1998

An elevation of stem cell factor in patients with hyperthyroid Graves' disease.

Graves' disease is an autoimmune disorder characterized by the presence of antibodies against thyrotropin receptor (TRAb). Stem cell factor (SCF), derived from bone marrow, is known to promote lymphohematopoiesis. To investigate the relation between the alteration in plasma levels of SCF, thyroid hormone status, and TRAb measured by thyrotropin binding inhibition (TBI), 13 untreated, 21 treated, and 4 relapsed hyperthyroid Graves' disease patients, 21 patients with Hashimoto's thyroiditis, 6 patients with subacute thyroiditis, and 11 control subjects were examined. In untreated hyperthyroid Graves' disease patients, serum levels of thyroxine (T4) and triiodothyronine decreased rapidly by methimazole treatment, and TBI decreased progressively, but variably. Simultaneously, the elevated plasma levels of SCF decreased gradually and progressively. The plasma levels of SCF correlated curvilinearly with the serum levels of T4. In 4 patients with relapsed hyperthyroid Graves' disease, TBI was marginally positive in 3 patients and negative in 1, but plasma levels of SCF were elevated significantly in all 4 patients. In patients with subacute thyroiditis and Hashimoto's thyroiditis with or without T4 replacement, plasma levels of SCF did not differ from that of controls. These findings indicate that the elevation of plasma levels of SCF relates to the longstanding thyrotoxic state and that short-term thyrotoxicosis does not significantly affect plasma levels of SCF. It remains to be determined whether the elevation in plasma levels of SCF is induced by excess thyroid hormone, reflecting the hypermetabolic state, or whether the elevation of plasma levels of SCF contributes to stimulation of lymphocytes producing TRAb.

Acute Disease↗