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Biomedical subjects

Y Endo

Publications and source records attributed to Y Endo.

At least 451 records · Page 25Linked to original sources

Heat-induced aggregation of recombinant erythropoietin in the intact and deglycosylated states as monitored by gel permeation chromatography combined with a low-angle laser light scattering technique.

Aggregate formation of recombinant human erythropoietin (r-EPO) on heat-treatment was followed by gel permeation chromatography combined with a low-angle laser light scattering technique under various conditions with respect to pH and salt concentration in order to provide basic knowledge about the change strictly required to be monitored for medicinal proteins. When heated at 60 degrees C at neutral pH, an aggregate with a limited size consisting of about 20 r-EPO molecules was formed. On heating at 50 degrees C at acidic pH, aggregation was unlimited. The aggregation proceeded non-covalently in acidic pH, but in alkaline pH covalent bond formation was also involved. Increase in salt concentration enhanced the aggregation. Deglycosylation of the N-linked oligosaccharides made r-EPO remarkably susceptible to aggregation on heat-treatment, indicating that the carbohydrate chains are essential to the stability of r-EPO.

Animals↗

Experimental metastasis of oncogene-transformed NIH 3T3 cells in chick embryo.

By means of a highly sensitive and quantitative assay for specific detection of metastasized tumor cells in chick embryonic organs using the polymerase chain reaction (PCR), we have examined the experimental metastatic ability of individual clones of NIH 3T3 cells, transformed with oncogenes: v-Ki-ras, v-Ha-ras, v-src, v-fos, and v-abl. Such a transformed clone had different metastatic abilities in different embryonic organs. Among them, two clones of NIH 3T3 cells transformed with ras-oncogenes (v-Ki-ras or v-Ha-ras) metastasized to liver and lungs of chick embryo, and grew there more rapidly than the other clones. The parental NIH 3T3 cells were detected as slight bands of PCR products after iv injection, indicating some cells were trapped in chick embryonic organs, but did not grow. These findings indicate that the transformed cells are able to invade the organ tissues and grow in embryonic chick organs, but non-metastatic cells such as the untransformed-NIH 3T3 cells are not able to grow in the secondary sites. These experiments clearly demonstrate the usefulness of this assay system to study genes involved in malignant transformation.

3T3 Cells↗

Atypical adenoma of the thyroid. A clinicopathologic and flow cytometric DNA study in comparison with other follicular neoplasms.

A clinicopathologic and DNA flow cytometric study was performed on seven patients (three males, four females) with atypical adenoma of the thyroid gland, using formalin-fixed paraffin-embedded tissues. The results were compared with those of 30 follicular adenomas and 13 follicular carcinomas. The patients ranged in age from 32 to 74 years (mean; 55.8 years), and the mean follow-up period was 11.0 years. All patients except two who died of other diseases were free of thyroid disease after initial surgery. It showed that there was no evidence of clinical cancer in this follow-up study of patients operated on for atypical adenomas. Four of the atypical adenomas were diploid, two were aneuploid, and one was tetraploid. Twenty-seven of the 30 follicular adenomas were diploid. Three patients with aneuploid follicular adenoma were free of disease. Of the 13 follicular carcinomas with a mean follow-up period of 6.9 years, five were diploid, seven were aneuploid, and one was tetraploid. Two patients with aneuploid follicular carcinoma and one with diploid carcinoma developed lung metastases, and one patient each with diploid and aneuploid follicular carcinoma died of disease. There was no significant correlation between histologic features, ploidy status and prognosis among follicular carcinomas. The results of this study suggest that DNA flow cytometric analysis is not a useful tool for predicting the clinical behavior of follicular neoplasms.

Adenoma↗

The effect of lipopolysaccharide, interleukin-1 and tumour necrosis factor on the hepatic accumulation of 5-hydroxytryptamine and platelets in the mouse.

1. Injection of lipopolysaccharide (LPS; 0.5-500 microgram kg-1) into mice induced a dose-dependent, slowly developing increase in hepatic content of 5-hydroxytryptamine (5-HT). This sustained increase could not be attributed to an LPS-induced alteration of the pharmacokinetic handling of 5-HT by stimulation of its uptake or inhibition of its degradation. 2. Regional differences were apparent in the tissue content of histamine and 5-HT between mast cell-deficient (W/Wv) and normal (+/+) mice. LPS administration (0.5 mg kg-1) gave comparable increases in the hepatic level of 5-HT in mast cell-deficient and normal mice. 3. Reserpine pretreatment (1 mg kg-1) selectively reduced 5-HT levels in the blood, spleen, liver, brain and lung of normal mice. Prior treatment with this agent also abolished the LPS (0.5 mg kg-1)-induced hepatic accumulation of 5-HT. 4. Accumulation of 5-HT in the liver by LPS (0.1 mg kg-1) was temporally associated with both a fall in the levels of circulating platelets, and a reduction in the concentration of 5-HT in the blood. The LPS dose-dependent (0.5-500 micrograms kg-1) increase in hepatic 5-HT content was associated with a similar dose-dependent reduction in the circulating levels of 5-HT. 5. Interleukin-1, alpha and beta (10 micrograms kg-1) and tumour necrosis factor alpha (TNF alpha) (1 mg kg-1) significantly enhanced the accumulation of 5-HT within the liver. Administration of TNF alpha (10 micrograms kg-1) potentiated the increase in hepatic 5-HT content seen with IL-1 beta (10 micrograms kg-1). 6. Electron microscopy revealed numerous platelets in the sinusoidal and perisinusoidal Disse spaces within the liver, in animals pretreated with LPS (0.1 mg kg '). The platelets retained their intact structure and showed no evidence of degranulation. 7. These data suggest that the LPS and cytokine-induced mobilization of 5-HT in the liver is associated with the hepatic translocation of platelets. This migration appears to be independent of platelet aggregation.

Animals↗

Ornithine and histidine decarboxylase activities in mice sensitized to endotoxin, interleukin-1 or tumour necrosis factor by D-galactosamine.

1. An injection of D-galactosamine (GalN) into mice together with a lipopolysaccharide (LPS or endotoxin), interleukin-1 (IL-1) or tumour necrosis factor (TNF), sensitized the mice and induced fulminant hepatitis with severe congestion resulting in rapid death. Since LPS and these cytokines induce ornithine decarboxylase (ODC) and histidine decarboxylase (HDC) in the liver and spleen of mice, the effects of GalN on the induction of ODC and HDC in these organs were examined. 2. The induction of ODC by LPS, IL-1 or TNF was suppressed by GalN in the liver, and this suppression preceded the hepatic congestion. There was good agreement between the degree of hepatic congestion and the suppression of ODC induction by various amounts of GalN. The induction of ODC in the spleen was suppressed only at the highest dose of GalN examined. 3. GalN is known to deplete uridine 5'-triphosphate (UTP), resulting in the suppression of RNA and protein synthesis. An injection of uridine, the precursor of UTP, diminished the GalN-induced suppression of ODC induction by LPS and prevented the hepatic congestion and death. 4. LPS-pretreatment before injection of LPS plus GalN prevented the suppression of ODC activity and prevented the hepatic congestion and death. 5. An injection of putrescine, the product of ODC, prolonged survival time and delayed the development of hepatic congestion. However, injection of an ODC inhibitor into the mice given LPS did not produce hepatic congestion. 6. The induction of HDC in the liver by LPS, IL-1 or TNF was not suppressed by GalN and, at high doses, the response to LPS was enhanced. An inhibitor of HDC neither prevented the hepatic congestion nor enhanced the protective effect of putrescine.7. Although GalN in combination with IL-la induced a markedly higher HDC activity than was observed when it was combined with TNFa, and suppressed the induction of ODC, the former combination at the doses used did not produce hepatic congestion or death. However, the sensitization to TNFa by GalN was markedly potentiated by IL-la.8. These results suggest that suppression of the induction of ODC by GalN may be one cause of the sensitization to LPS, IL-1 or TNF, and that the induction of HDC, i.e. histamine formation, may not be involved in this sensitization.9. These results are consistent with the hypothesis that both IL-1 and TNF are involved in the sensitization to LPS.

Animals↗

Efficacy of nafamostat mesilate as a regional anticoagulant in experimental direct hemoperfusion and in plasma exchange on humans.

As an anticoagulant, we compared Nafamostat mesilate (FUT) to heparin in experimental direct hemoperfusion (DHP) and studied the efficacy of FUT in clinical plasma exchange (PE). In in vitro study, FUT (5 micrograms/ml) inhibited the activation of C4 more strongly than heparin (100 U/h), and larger dose of FUT (50 micrograms/ml) inhibited the activation of C3. Experimental DHP with FUT on jaundiced dogs was safely performed, but not with heparin. Clinical PE with FUT was safely performed and the hemostatic condition was not aggravated either during or after PE in patients with bleeding.

Animals↗

Expression of the angiotensinogen gene and localization of its protein in the human heart.

BACKGROUND: There have been no reports on the presence of the tissue renin-angiotensin system in the human heart, although the presence of angiotensinogen has been described in the animal heart. METHODS AND RESULTS: To determine whether angiotensinogen is synthesized in the human heart, we examined angiotensinogen messenger RNA (mRNA) synthesis in autopsy hearts by using ribonuclease protection assay. As a result, angiotensinogen mRNA was detected in the atrial muscle, muscles of the conduction system, and the left ventricular wall. In the left ventricular wall, mRNA expression was more prominent in the subendocardial muscles than in the midcardial or epicardial muscles. Using a monoclonal antibody to human angiotensinogen in immunoblotting experiments, we detected two closely spaced bands at approximately 70 kd in the heart, which was quite consistent with the human angiotensinogen molecule. Immunohistochemical studies with this monoclonal antibody demonstrated intense immunoreactivity in the atrial muscles, the muscles of the conduction system, and those of the subendocardial layers. CONCLUSIONS: We conclude that angiotensinogen was synthesized in the human heart. It was evident that the localization of angiotensinogen was not ubiquitous in the cardiac muscles, showing its predilection for the atrial muscles, muscles of the conduction system, and subendocardial layer of the left ventricle.

Angiotensin II↗

Increases in cerebral blood flow in rat hippocampus after medial septal injection of naloxone.

BACKGROUND AND PURPOSE: In a previous study, we occasionally found that the rat given naloxone in the preoptic region develops behavioral seizures. In view of knowledge that the forebrain including the medial septal nucleus provides cholinergic projections to the hippocampal formation, the present study examined the effects of naloxone injected into the medial septal nucleus on the local blood flow in the hippocampus. METHODS: A polyurethane-coated platinum electrode with a 1-mm bare tip for measurement of blood flow and a guide cannula made of stainless steel tube for naloxone injection were implanted chronically into the brain. The cerebral blood flow was measured by the hydrogen clearance method in freely moving rats. RESULTS: The injection of 50 micrograms naloxone caused a significant increase in hippocampal blood flow, with its peak at 20 minutes. Twenty micrograms naloxone caused a similar increase, but 10 micrograms caused only a slight increase that peaked at 30 minutes, suggesting a dose-response of naloxone effect. Hippocampal blood flow was not changed after the injection of saline into the medial septal nucleus and after the injection of naloxone into the caudate nucleus. CONCLUSIONS: Taken together with previous findings, the results suggest that endogenous opioids exert a decreasing effect on the local blood flow in the hippocampus, probably mediated by the magnocellular cholinergic neurons projecting to the hippocampus.

Animals↗

[Improving effect of the synthetic protease inhibitor E-3123 on experimental DIC in dogs].

Disseminated intravascular coagulation (DIC) is a severe syndrome associated with generalized, intractable bleeding and multiple organ failure. Synthesized protease inhibitors such as gabexate mesilate and nafamostat mesilate show an improving effect on DIC, which develops by a chain reaction involving the coagulation, fibrinolysis, complement and kallikrein systems. Experimental DIC was developed in Beagle dogs by infusion of 150 U/kg tissue thromboplastin (Group I), and the improving effect of a new synthetic protease inhibitor, E-3123, was examined. The following groups of animals were treated with drugs: Group II (n = 4) was given with 5 mg/kg/hr of E-3123; group III (n = 4) was given 10 mg/kg/hr of E-3123; and group IV was given 6 mg/kg/hr of gabexate mesilate (GM). Although improvement of the hemodynamics or peripheral circulation was not apparent, a slight, but insignificant, improvement of lactate/pyruvate was noted in the treated groups. On the other hand, the hemostatic abnormalities such as prolongation of prothrombin time and activated thromboplastin time; decreases of platelet count, fibrinogen and alpha 2-antiplasmin; and increases of fibrin degradation products were significantly improved in the treated groups. These results indicate that E-3123 is effective for improving experimental DIC, and it is suggested that E-3123 is applicable for the treatment of clinical DIC.

Animals↗

Structure of G-CSF: significance of the sugar chain.

1. The carbohydrate chain protects rhG-CSF from polymerization and/or conformational alterations associated with physicochemical changes, elevation of pH or temperature fluctuations. 2. The carbohydrate chain of rhG-CSF prevents loss of its biological activity in normal human serum by inhibiting proteinase activity. 3. These facts indicate that the carbohydrate chain of rhG-CSF has a markedly important role in maintaining the stability of the protein itself as well as in effecting the exertion of its biological activity.

Carbohydrates↗

[Clinical investigation of individual differences in evoked otoacoustic emission].

Factors causing individual differences in evoked otoacoustic emission (e-OAE) were investigated in 223 ears of 159 persons with normal hearing. After recording e-OAE to click by using ILO88, the relation between the intensity of e-OAE and factors such as age, sex, small differences in hearing, volume of the external auditory canal, static compliance, developmental extent of the mastoid cavity and presence or absence of spontaneous otoacoustic emission (s-OAE) were studied. The volume of the external auditory canal and static compliance were estimated from a tympanogram measured by Teledyne TA-2C and the developmental extent of the mastoid cavity was measured with a Schüller X-ray film. A correlation was found between the intensity of e-OAE and two factors, the age and the s-OAE, but not between the intensity of e-OAE and other factors. From the fact that the percentage of s-OAE present declines with aging, the presence or absence and the characteristics of s-OAE were considered to be a factor causing individual differences in e-OAE.

Acoustic Stimulation↗

[Negative ideal-self as a standard of self-esteem].

The concept of negative ideal-self is introduced as a contrast to positive ideal-self. Discrepancies between positive ideal-self and real-self (Dp-score) have been associated with low self-esteem. The present study purported to see whether negative ideal-self may be a standard of self evaluation, and to what extent discrepancies between negative ideal-self and real-self (Dn-score) relate with self-esteem (Rosenberg). The results showed that both Dp-score and Dn-score correlate significantly with self-esteem, but the latter showed higher correlation than the former. It is suggested that self-esteem is more a function of distance that how 'I' am not the person which 'I' want to be. These findings were discussed from the importance of an approach to negative aspects of the self.

Adult↗

Characterization, self-assembly and reattachment of S layer from Clostridium botulinum type E saroma.

S layer of Clostridium botulinum type E Saroma and its subunits were isolated and characterized for their chemical and morphological properties. The S layer was composed of a number of subunits with apparent molecular weights ranging from about 10 to 150 kDa. The isolated S layer subunits possess the ability to assemble into recrystallized flat sheets in the absence of any supporting layer and to reattach to the cell wall from which they have been removed. Immunoblot analysis using an antiserum against whole cells of the organism showed that 60 kDa and 90 kDa subunits of the S layer were major somatic antigens of the organism. Immunogold-labeling using monospecific antiserum raised to the individual 60 and 90 kDa proteins revealed that both subunits were exposed evenly over the entire cell surface. The amino acid compositions of both subunits showed that aspartate and glutamate were predominant whereas cystine and methionine were poor. The amino acid composition and acidic property of the two subunits of the S layer agree well with the results obtained from the S layers of other bacterial species as well as other pathogenic clostridia.

Amino Acid Sequence↗

In vitro self-assembly of the S layer subunits from Clostridium difficile GAI 0714 into tetragonal arrays.

Regularly arrayed surface component (S layer) of Clostridium difficile strain GAI 0714 was isolated with 4 M guanidine hydrochloride from the cell wall of the organism, and examined for self-assembly in vitro. The S layer was composed of two different protein subunits with molecular weights of 32 kDa and 45 kDa. Optical diffraction analysis revealed that the morphological units of both native and self-assembled S layer were essentially identical and composed of a rhombus possessing each side of 8.1 nm and interior angle of 88 degrees. The self-assembly of S layer subunits were induced in the presence of divalent cations such as Ca2+ or Zn2+, but Ba2+ or monovalent cations including K+, Na+ and Li+ failed to induce self-assembly. These results suggest that Ca+2 or Zn+2 may act as bridges to link negatively charged surface subunits.

Bacterial Outer Membrane Proteins↗

Expression of genes encoding type IV collagen-degrading metalloproteinases and tissue inhibitors of metalloproteinases in various human tumor cells.

Uncontrolled expression of matrix metalloproteinases 2, 3 and 9 (MMP-2, -3 and -9) is believed to be a critical part of the invasive potential of tumor cells because of their ability to degrade type IV collagen, a major structural component of basement membranes. Availability of proteolytic activity in the vicinity of the cell surface is further affected by a local balance between the enzymes and their inhibitors produced by the cell. To determine how frequently deregulated expression of the MMPs and tissue inhibitors of metalloproteinases (TIMPs) is associated with tumor cells, 26 human tumor cell lines were examined by Northern blotting. Transcripts for MMP-2 and MMP-9 were more frequently expressed in mesenchymal tumor cells (9/9 for MMP-2 and 6/9 for MMP-9) than in epithelial tumor cells (4/17 for MMP-2 and 2/17 for MMP-9). Although expression of MMP-2 mRNA was clearly cell type-specific, MMP-9 mRNA expression in mesenchymal cells correlated well with the reported tumorigenicity of the cells. Enhanced expression of MMP-9 mRNA was also associated with the tumorigenic transformation of cells by an activated c-H-ras gene in human embryonic fibroblasts. Only 3 of the 26 tumor cells expressed MMP-3 mRNA, and 2 of the 3 were epithelial tumor cells which coordinately expressed MMP-9 and TIMP-1 mRNAs. TIMP-1 mRNA was almost undetectable in 50% of the tumor cells, but TIMP-2 mRNA was expressed in the majority of the cells. These findings provide comprehensive information about mRNA expression of the MMPs and TIMPs in tumor cells, the deregulation of which is thought to be an integral part of the invasive potential of tumor cells.

Cell Transformation, Neoplastic↗

[Clinical studies on intravaginal administration of CDDP for dysplasia, carcinoma in situ and microinvasive carcinoma of the uterine cervix].

We attempted CDDP (cis-diaminedichloroplatinum) intravaginal administration by directly exposing the uterine cervix to CDDP in cases of dysplasia of the uterine cervix and cervical intraepithelial and micro-invasive carcinoma. Out of 12 patients, 7 had dysplasia of the uterine cervix (dysplasia was mild in 4, of an intermediate level in 1, 4 with mild dysplasia, 1 with and advanced in 2); 3 had carcinoma in situ, and 2 had microinvasive carcinoma. For CDDP intravaginal administration, a gauze tampon containing CDDP (5mg) was inserted into the vagina. CDDP administration was repeated daily for 10 days. The total dosage of CDDP administered was 50mg (new paragraph). During this period, vaginal cytologic examination was conducted and total plasma Pt content was determined daily for all. Following the completion of CDDP administration, the uterine cervices of those with dysplasia were histologically examined. For those with carcinoma in situ and microinvasive carcinoma, simple total hysterectomy was performed after intravaginal administration of CDDP to determine its therapeutic efficacy and the Pt concentration of the tissue; 1. In the 7 cases of dysplasia, dysplastic cell degeneration was observed 1-2 days after the start of intravaginal CDDP administration and these cells disappeared in all cases after its completion. 2. Sixteen histological sections of the resected cervical specimens from the 3 cases of carcinoma in situ showed complete disappearance of cancerous cells. 3. In the 2 cases of microinvasive carcinoma, no tumor cells were detected in one case; in the other case, tumor cells persisted in part of the resected specimen.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Intravaginal↗