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Biomedical subjects

H Ikeda

Publications and source records attributed to H Ikeda.

At least 793 records · Page 44Linked to original sources
PubMed1992

Stimulus-specific enhancement of luminol chemiluminescence in neutrophils by phosphatidylserine liposomes.

When stimulated with different stimuli, neutrophils generate various active oxygen species. These active oxygen molecules can be analyzed by luminol chemiluminescence (LCL). Phosphatidylserine (PS)-liposomes increased the formylmethionyl-leucyl-phenylalanine-induced LCL of guinea pig peritoneal neutrophils without affecting their oxygen consumption and superoxide (O2.-) generation. Similar effects of PS-liposomes were also observed in LCL of neutrophils stimulated by phorbol myristate acetate or arachidonic acid but not by opsonized zymosan. Kinetic analysis revealed that the PS-liposome-induced increase in LCL depended on extracellulary generated O2.-. Moreover, the stimulatory effect of PS could be seen only when it formed liposomal membranes. The effect of PS-liposomes was also inhibited by superoxide dismutase, catalase, and deferoxamine, an iron chelator, but not by azide, an inhibitor of myeloperoxidase. Similar enhancement of stimulation-dependent LCL response was also observed with Fe3+ and ADP-Fe3+, but the degree of enhancement was much greater with PS-liposomes than with iron and its complex. The increase in hydroxyl radical generation by PS-liposome-treated neutrophils was confirmed by experiments with EPR spectrometry using spin-trapping agents. These results suggested that the interaction of neutrophils with PS-containing membrane surface might generate reactive oxygen species that enhance the stimulus-dependent LCL response of neutrophils.

Animals↗
PubMed1992

Electrophysiological properties of neurones following mild and acute retinal ischaemia.

Early electrophysiological changes following acute retinal ischaemia were studied by recording single or multiunit retinal ganglion cells and the electroretinogram (ERG) in barbiturate anaesthetized cats. Retinal ischaemia was initiated photochemically by platelet aggregation in retinal vessels which had been irradiated with monochromatic green light following an intravenous injection of Rose Bengal dye. No physiologically active ganglion cells were found within, or close to, the irradiated sites with chorioretinal oedema. On the other hand, in the areas 5-20 degrees away from the irradiation sites, ganglion cells had abnormally raised spontaneous (background) firing which obscured visually driven firing. The retinal areas where no physiologically active ganglion cells were found showed histopathological changes which are similar to those described for glutamate-induced retinal damage. Retinal areas where depolarized retinal ganglion cells were located, however, showed only minor vacuolation of the ganglion cell fibre layer. Early global electrophysiological changes following photochemically induced retinal vascular lesion were consistent with those predicted from the findings in the single cell study. Vascular lesions produced with high irradiation energy (10-30 J), which promote extensive chorioretinal oedema, resulted in gradual loss of visually responsive ganglion cells. Lesions produced by low-energy irradiation (2 J), causing slight narrowing of the blood columns in the vessels, on the other hand, resulted in significant increases in the amplitude and the implicit time of the ERG b-wave and the background firing of multiunit retinal ganglion cells. Electrophysiological changes associated with mild retinal ischaemia are analogous to physiological effects associated with exogenous glutamate or blockade of glutamate uptake.(ABSTRACT TRUNCATED AT 250 WORDS)

Action Potentials↗
PubMed1992

Sites of relapse in patients with neuroblastoma following bone marrow transplantation in relation to preparatory "debulking" treatments.

Forty-one patients with high-risk neuroblastoma were treated between September 1977 and December 1987 at the Children's Hospital of Philadelphia with supralethal chemotherapy and total-body irradiation rescued by bone marrow transplantation. Twenty-six patients were treated following relapse and 15 were newly diagnosed. At the time of evaluation, January 1991, 11 of 41 patients (26.8%) remained in complete remission. Actuarial survival rates of patients transplanted following relapse were 0.35 and 0.31 at 2 and 5 years, respectively, and actuarial disease-free survival rates were 0.38 at 12 months and 0.27 at 24 months. The 2- and 5-year actuarial survival values for the patients with newly diagnosed disease were 0.53 and 0.25, respectively, and the 12- and 24-month disease-free survival rates were 0.47 and 0.27, respectively. There was no significant difference in survival between these groups. Twenty-nine of the 41 patients reviewed were available for analysis of the effect of local treatment. Thirteen had a combination of surgery and radiation (RT), 2 had surgery alone, 9 had RT alone, and in 5 patients no local treatment was given. The local relapse rate was 17%; it was 15% following surgery plus RT and 22% following RT alone. The failure rate combining local and distant relapse is 62% for surgery plus RT and 44% for RT alone. Although a local relapse rate of 17% is imperfect, it is a relatively small contribution to the overall relapse of 62%.

Adrenal Gland Neoplasms↗
PubMed1992

Tumour necrosis factor causes an increase in axonal transport of protein and demyelination in the mouse optic nerve.

An increase in fast axonal transport of protein by the optic nerve was found in mice following a single combined injection of human recombinant tumour necrosis factor alpha (rTNF) and [3H]proline into the vitreous chamber. Demyelination was observed in optic nerve fibres arising from the eyes of mice which received a single rTNF injection. No such changes were detected when heat-inactivated rTNF was injected with the label. The effects of intravitreal injection of rTNF on the pathophysiology of mouse optic nerve resembled those found in mice infected with Semliki Forest virus (SFV), an animal model of multiple sclerosis. We suggest that TNF could mediate at least some of the pathophysiological changes found in SFV-infected mice and may provide a clue concerning the disease mechanism in multiple sclerosis.

Animals↗
PubMed1992

Molecular analysis of a HTLV-IpX defective human adult T-cell leukemia.

Fresh and cultured leukemia cells from an adult T-cell leukemia (ATL) patient which possessed gag and env gene defective human T-cell leukemia virus type I (HTLV-I) provirus genome were molecularly analyzed. Cells from both fresh and the established cell line, named KB-1 showed identical surface markers of helper T cells, expressed the interleukin 2 (IL-2) receptor and had an identical defective HTLV-I provirus genome with deletions of the gag and env genes involving pX gene exon 2. The KB-1 cells grew vigorously in vitro, even in the absence of IL-2 and the culture supernatant of KB-1 contained a large amount of IL-2. Neither pX mRNA nor p40(TAX) protein was detected in the KB-1 cells. The collective evidence suggests that the pX gene was not functioning in this particular ATL case. The biological function of the HTLV-I genes, especially the pX gene is discussed in relation to the early and late leukemogenesis of ATL.

Blotting, Southern↗
PubMed1992

Effect of an intestinal disaccharidase inhibitor (AO-128) on obesity and diabetes.

A new disaccharidase inhibitor, AO-128, showed 190-3900-fold more potent inhibition of purified rat small intestine sucrase-isomaltase (S-1) complex and 23-33-fold more potent inhibition of semipurified porcine small intestine disaccharidases than acarbose. AO-128 suppressed elevation of the blood glucose concentration after oral sucrose, maltose, and starch, but not after oral glucose, fructose, and lactose. The chronic addition of AO-128 to the diet produced antiobesity and antidiabetic actions in obese and/or diabetic animals. Undesirable side effects, such as diarrhea and soft feces, were observed only for the first 5-7 d and suppression of intestinal disaccharidase activities was observed even at the end of the experiment, suggesting that the suppressive or delaying effect of AO-128 on elevation of the postprandial blood glucose concentrations is involved in reduction in body weight gain and prevention and/or amelioration of the diabetic state. Thus, AO-128 is useful as an adjunct to the dietary management of obesity and diabetes.

Acarbose↗
PubMed1992

Dietary ascorbic acid depresses plasma and low density lipoprotein lipid peroxidation in genetically scorbutic rats.

The effects of dietary ascorbic acid on plasma lipoprotein and liver lipid peroxide concentrations were examined using ODS od/od rats with a genetic defect in the ability to synthesize ascorbic acid. ODS od/od rats were fed purified diets supplemented with 0 to 300 mg ascorbic acid/kg diet for 21 d. An ascorbic acid-free diet induced body weight loss, depleted ascorbic acid in the plasma and increased thiobarbituric acid-reactive substances in the plasma and liver as compared with rats fed ascorbic acid supplemented diets and with normal ODS +/+ rats fed the ascorbic acid-free diet. Increasing ascorbic acid concentration in the diet inhibited the development of these ascorbic acid deficiency symptoms in a dose-dependent manner. The dietary requirement of ascorbic acid to maintain normal body weight gain and plasma lipid peroxide concentrations was approximately 150 mg ascorbic acid/kg diet. On the other hand, even 300 mg ascorbic acid/kg diet was insufficient to maintain a hepatic concentration of ascorbic acid comparable to that in the liver of ODS +/+ rats. The lipid peroxide concentration in plasma LDL and liver was significantly elevated in ODS od/od rats fed the ascorbic acid-free diet. Supplementing the diet with 300 mg ascorbic acid/kg kept those concentrations within the normal ranges seen in the ODS +/+ rats.

Animals↗
PubMed1992

Species-specific epitopes exist on the cytoplasmic amino-terminal domain of erythrocyte band 3 protein.

Monoclonal antibodies (P3-9H, P3-1F, P3-2H, P3-4A, and P3-4C) to human erythrocyte band 3 were produced using human erythrocyte membranes as the immunogen. All epitopes defined by these antibodies were found on the amino-terminal cytoplasmic domain of erythrocyte band 3. The antibodies crossreacted variously with erythrocyte band 3 of primates (chimpanzee, orangutan, Rhesus monkey, Japanese monkey, spider monkey, and capuchin monkey) in enzyme-linked immunosorbent assay. P3-9H did not crossreact with erythrocyte band 3 of any primate examined; P3-1F crossreacted only with that of chimpanzee; P3-2H crossreacted with erythrocyte band 3 of chimpanzee, spider monkey, and capuchin monkey; and P3-4A and P3-4C crossreacted with erythrocyte band 3 of all primates examined. These results suggest that evolutional changes in primates are accumulated in the amino-terminal cytoplasmic domain of band 3 and that species-specific epitopes exist on this domain.

Animals↗
PubMed1992

Scheme for the generation of a truncated endogenous murine leukaemia virus, the Fv-4 resistance gene.

The Fv-4 resistance (Fv-4r) gene is a truncated endogenous murine leukaemia virus (MuLV) containing a 3' portion of pol, the entire env gene and the 3' long terminal repeat. Env expression renders mice resistant to infection by ecotropic MuLVs, probably via receptor interference. Previous studies have suggested that the flanking cellular sequences are also important for Fv-4 env gene expression. To establish how the truncated retrovirus was generated and the nature of the cellular sequences involved, the Fv-4 susceptible (Fv-4s) allele DNA was cloned, and its restriction map and nucleotide sequence were compared with those of the Fv-4r allele. A likely mechanism for generation of the truncated endogenous MuLV is suggested by the results; integration of a prototype MuLV provirus at a site within the Fv-4s allele about 6 to 8 kb downstream of a non-retroviral promoter region, followed by deletion of the 5' half of the provirus, with an accompanying loss of only 7 or 10 bp of cellular flanking sequences. The deletion may have led to the expression of the Fv-4r env gene under control of the non-retroviral promoter.

3T3 Cells↗
PubMed1992

An intrinsic thymic epithelial abnormality is responsible for the spontaneous development of predominantly lymphocytic thymomas in BUF/Mna rats.

The nature of tumorigenesis of predominantly lymphocytic thymoma was examined using an animal model. Rats of the inbred BUF/Mna strain were found spontaneously to develop predominantly lymphocytic thymomas, histologically indistinguishable from their human counterparts, at an incidence of virtually 100%. Thymic rudiments of BUF/Mna rats grafted 17 months previously under the renal capsule of young athymic ACI/NMs-rnu/rnu rats also gave rise to similar lesions. The lymphocytes in the thymomas expressed T-cell antigens (rat Lyt-1 and Lyt-2.3), as in the normal case, and ACI rat specific antigen. When BUF/Mna rats of thymoma age were irradiated with a lethal dose of 12 Gy and then received a single injection of bone marrow cells (8 x 10(7)) from BALB/c-nu/nu mice, thymomas were re-formed three weeks later (in 2 of 5 rats) with the replacement lymphocytes expressing mouse Thy-1.2 antigen. These results indicate that an intrinsic thymic epithelial abnormality is responsible for the development of predominantly lymphocytic thymomas in BUF/Mna rats.

Animals↗
PubMed1992

Nodular sclerosing Hodgkin's disease showing positive reaction for anti-IL 6/BSF2 antibody.

A 53-year-old man presented with bilateral cervical lymph node swelling and low fever. Swollen lymph node was biopsied, and diagnosed as nodular sclerosing Hodgkin's disease (HD). By combined radio- and chemotherapy, he went into complete remission. After 3 years, fever of 38-39.2 degrees C and lymph node swelling appeared in the para-aortic region and later became systemic. A biopsy was diagnosed as syncytial variant of HD with aid of immunohistochemistry on frozen sections. Large atypical mono- or binucleated cells reacted with anti-interleukin 6 (IL-6) antibody. The patient's disease progressed with fever, and he died 66 months after the onset of disease. A previous biochemical study showed that IL-6 displayed a real relation to the generation of fever. Therefore it is suggested that fever in this patient is related to IL-6.

Combined Modality Therapy↗
PubMed1992

A case of adult T-cell leukemia/lymphoma, histologically presenting CD30-positive large cell lymphoma.

A 48-year-old Japanese woman with adult T-cell leukemia/lymphoma (ATLL), histologically presenting CD30-positive large cell lymphoma is reported. The patient, who was from an ATLL endemic area in Japan, had cutaneous nodules in the head, trunk, and extremities, and cervical lymph node swelling; these had been found three months before her admission to our hospital. A biopsy specimen of a skin lesion showed diffuse large cell lymphoma; the lymphoma cells were positively stained with CD30 (Ki-1/Ber H-2), CD4 (helper-T), and CD25 (interleukin-2 receptor) antibodies. Anti HTLV-1 antibody (ATLA) was detected in the serum, and molecular cytogenetic studies of lymphoma cells showed both positive T-cell receptor rearrangement and HTLV-1 specific DNA sequences.

Antigens, CD↗
PubMed1992

Intracerebral schwannoma: case report.

A case of intraparenchymal schwannoma is presented. The neuroradiological findings of reported intraparenchymal schwannomas, including the case reported here, are discussed. The specific tumor characteristics are emphasized. This report appears to be the only documentation as a result of magnetic resonance imaging of this specific tumor.

Adolescent↗
PubMed1992

Effect of manidipine on balloon catheter-induced arterial smooth muscle cell proliferation in spontaneously diabetic GK rats.

The inhibitory effect of manidipine, a long acting calcium channel blocker, on vascular smooth muscle cell proliferation was investigated in spontaneously diabetic GK rats with balloon catheter-induced denudation of the carotid artery. Treatment with manidipine at doses of 4.6 and 15.1 mg/kg/day inhibited thickening of the neo-intima in the balloon catheter-injured artery without any effect on blood pressure and lowered the ratio of intima to wall areas and wall to total vascular areas in a dose-dependent fashion. These results suggest that manidipine inhibits an abnormal proliferation of the intima in the carotid artery of spontaneously diabetic rats.

Animals↗
PubMed1992

In vitro oxygenation injury to slices prepared from ischemic kidney in rats.

When cortical slices prepared from rat kidneys made ischemic were incubated under a 100% oxygen atmosphere, lipid peroxidation increased and the ATP level decreased. Such oxygenation of the slices was accompanied by decreases in gluconeogenesis and the glutathione level, but an antioxidant, N,N'-diphenyl-p-phenylenediamine, prevented the increase in lipid peroxidation without affecting decreases in ATP and glutathione levels, and gluconeogenesis. The results suggest that postischemic oxygenation of slices generates free radicals that cause the production of lipid peroxidation not associated with tissue injury.

Adenosine Triphosphate↗
PubMed1992

[Hematological and serum biochemical changes with age in term fetuses, offspring and dams in normal Sprague-Dawley rats].

Hematological and serum biochemical values of dams and offspring of Sprague-Dawley rats were measured during late gestation, lactation and postweaning. In dams, slightly low erythrocytic parameters, high platelets and high frequency of neutrophils were seen after parturition although WBC showed no marked changes. On Day 20 of gestation, glucose and triglycerides were extremely high and TP and albumin were low. These changes may be attributed to pregnancy or parturition. In fetuses on Day 20 of gestation and offspring immediately after birth, erythrocytes showed anisocytosis, polychromasia, basophilic stipplings and Howell-Jolly bodies and erythroblasts were found. RBC was low. MCV and MCH were extremely high, compared to adult erythrocyte levels. Hemoglobin and hematocrit slightly decreased before weaning. RBC, hemoglobin and hematocrit increased with age and reached adult levels by Day 56. MCV and MCH values decreased, towards adult levels, until weaning. Platelets rapidly increased and reached adult levels before weaning. WBC increased after birth having higher counts in males than in females on Day 35 and thereafter. Glucose, TP and albumin increased with age and reached adult levels by Day 28. ALP was high in fetuses and changed with age having two peaks similar to those reported in man. Cholesterols gradually increased after birth and had a peak on Day 14. Urea nitrogen, inorganic phosphorus and calcium were slightly high in fetuses and preweaned offspring. Potassium was high in fetuses but no age-related trends were seen in offspring.

Age Factors↗
PubMed1992

Sulfur amino acid levels and related enzyme activities in various brain regions (and other tissues) in normal mice and rolling mice Nagoya.

The contents of the sulfur amino acids, and the activities of cystathionine beta-synthase and cystathionine gamma-lyase were measured in various regions of the brain and several other tissues in both normal mice and rolling mice Nagoya. The cystathionine content and cystathionine beta-synthase activity were found to be unevenly distributed in various regions of the brain in both normal mice and rolling mice Nagoya, being highest in the cerebellum. Except for the mesencephalon and thalamus plus hypothalamus, the cystathionine content and cystathionine beta-synthase activity in the brain regions of rolling mice Nagoya were much higher than those of the normal mice. The cystathionine content after D,L-propargylglycine treatment was also found to be unevenly distributed in various brain regions in both normal mice and rolling mice Nagoya. The concentrations of cystine and methionine were also higher in all regions of the brain of rolling mice Nagoya than those of normal mice, while the concentration of taurine in the various regions of the brain was almost the same in normal mice and rolling mice Nagoya. Cystathionine beta-synthase and cystathionine gamma-lyase activities in the liver, kidney, and pancreas were almost the same in both the normal mice and rolling mice Nagoya.

Amino Acids, Sulfur↗