Search PubMed⌕ Search

Biomedical subjects

Y Goto

Publications and source records attributed to Y Goto.

At least 325 records · Page 18Linked to original sources
PubMed1998

Plasmin can reduce the function of human beta2 glycoprotein I by cleaving domain V into a nicked form.

beta2-Glycoprotein I (beta2GPI) is a highly glycosylated plasma protein with the ability to bind negatively charged substances such as DNA, heparin, dextran sulfate, and negatively charged phospholipids. The most relevant physiological role of beta2GPI is supposed to be the regulation of the function of anionic phospholipids like cardiolipin (CL). beta2GPI consists of a single polypeptide chain (326 amino acid residues) with a molecular mass of about 50 kD and with five tandem repeated domains (I, II, III, IV, and V). In the previous study, we found that factor Xa can produce the nicked form by cleaving Lys 317-Thr 318, using recombinant human domain V (r-Domain V). However, the reaction was extremely slow. In the present paper, we found that plasmin can produce the nicked form of domain V, using recombinant domain V (r-Domain V) and beta2GPI from human plasma. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, r-Domain V was rapidly cleaved into a nicked form by plasmin, very slowly by factor Xa, but not by thrombin, tissue-type plasminogen activator, urokinase, and tissue factor/factor VIIa. The cleavage site of r-Domain V and beta2GPI by plasmin was proved to be Lys 317-Thr 318 by amino acid sequence analysis of the digest and of the C-terminal peptide isolated by high-performance liquid chromatography. The cleavage was completely inhibited by plasmin inhibitor (alpha2PI). The nicked form was demonstrated to show reduced affinity for CL with a dissociation constant of one order of magnitude larger than that of the intact beta2GPI. To determine whether the specific cleavage of beta2GPI by plasmin can occur also in plasma, human plasma was first acid-treated to inactivate alpha2PI and then incubated with urokinase. About 12% of beta2GPI in plasma was nicked when alpha2PI activity decreased to 80%. The nicked form was not generated in plasminogen-depleted plasma. These results suggest that plasmin can produce the nicked form of beta2GPI with the reduced ability to bind phospholipids in vivo.

Amino Acid Sequence↗
PubMed1998

Infant temperament and child-rearing stress: birth order influences.

The relationship between an infant's temperamental difficulty and the mother's child-rearing stress was investigated in a sample of 128 children. Children's temperament was assessed by the Revised Infant Temperament Questionnaire (RITQ) at 6-7 months, and by the Toddler Temperament Scale (TTS) at 18 months. The mothers' child-rearing stress was assessed by a self-report questionnaire. At the children's age of 18 months, mothers of difficult children reported higher child-rearing stress than mothers of easy children. Although difference in the level of child-rearing stress reflecting birth order was not evident at either 6-7 months or 18 months, the proportion of child-rearing stress which could be explained by the children's temperament was highest for mothers of first-borns when their children were 18 months old.

Birth Order↗
PubMed1998

Retinal functional change caused by adenoviral vector-mediated transfection of LacZ gene.

We examined the effect of insertion of an exogenous gene on retinal function to assess the rationale of adenoviral vector-mediated gene transfer for future gene therapy. An adenoviral vector expressing bacterial LacZ (AdCALacZ) was injected into the eyes of adult rats either intravitreally (group A) or subretinally (group B), and the gene expression and retinal function were thus examined at different time points after gene transfer for 3 weeks. X-Gal histostaining showed that neural retinal cells were transfected in group A and that retinal pigment epithelial cells were transfected in group B. The gene transfer was more efficient in group B (54.4% of the fixed retinal area was stained) than in group A (10.4%). The electroretinogram (ERG) revealed retinal dysfunction in the AdCALacZ-transfected rats even at the stage in which the histological damage was not apparent by electron microscopy and immunohistochemical studies for cytokeratin, S-100 protein, and glial fibrillary acidic protein. The ERG change was correlated with the intensity of inflammation, and retinal function recovered to the original level by 3 weeks, along with a diminution of inflammation. Functional changes were more evident in eyes treated with AdCALacZ than in those infected with adenoviral vector with no exogenous gene; however, no histological difference was observed between these groups, indicating that the insertion of exogenous gene itself affects retinal function. The results showed that different kinds of retinal cells could be gene-transferred by an adenoviral vector, depending on the application method. The retinal dysfunction caused by each adenoviral transfection method was caused by inflammation and the insertion of exogenous gene, and this retinal dysfunction was recoverable. In future gene therapy, special attention should be given to the method of exogenous gene insertion in the retina.

Adenoviridae↗
PubMed1998

Determination of salicylic acid in human serum with capillary zone electrophoresis.

The determination of salicylic acid (SA), a metabolite of aspirin, in human serum was developed using capillary zone electrophoresis (CZE) with diode array detection. The reproducibility of separation and quantification with CZE analysis of the extract of SA from human serum was appropriate for the intra- and inter-day assay coefficients. A high correlation was revealed between the serum SA levels in volunteers determined by CZE and those determined by a fluorescence polarization immunoassay (r=0.973, n = 12), although the former values were slightly higher than the latter. There were no peaks interfering with the assay of SA by internal standard method. This CZE method could provide a simple and efficient method for monitoring SA in patients.

Administration, Oral↗
PubMed1998

Group additive contributions to the alcohol-induced alpha-helix formation of melittin: implication for the mechanism of the alcohol effects on proteins.

Detailed analysis of the effects of alcohols on proteins and peptides is important because of its wide range of applications in many fields. Whereas melittin, a major component of honeybee venom, is unfolded in an aqueous environment, the addition of alcohols induces an alpha-helical structure. We used circular dichroism (CD) to compare the effects of various alcohols on melittin. Whereas the alpha-helical state was basically independent of alcohol species, the effectiveness of alcohols varied significantly. Among alkanols, the effectiveness was proportional to the bulkiness of hydrocarbon groups, indicating that the hydrocarbon group contributes positively to the alcohol effects. Comparison of alcohols with the same hydrocarbon group but a different number of hydroxyl groups showed that the hydroxyl groups contribute negatively to the alcohol effects. Comparison of several halogenols indicated that halogen increases the effectiveness in the order of F < Cl < Br. These results suggested that the effects of alcohol can be interpreted by the additive contributions of each of the constituent groups of the alcohol, which are proportional to the solvent-accessible surface area. However, for markedly effective alcohols such as 1,1,1,3,3,3-hexafluoro-2-propanol, the aggregation of alcohols was suggested to further enhance these effects. We have constructed equations for estimating the effectiveness of alcohols in inducing alpha-helical structure, which should also be useful for predicting the other effects of alcohols on proteins.

Alcohols↗
PubMed1998

Previous angina reduces in-hospital death in patients with acute myocardial infarction.

There is little information on how previous angina influences in-hospital deaths secondary to acute myocardial infarction (MI). This study evaluated the causes of in-hospital deaths in MI patients with and without previous angina. A total of 2,264 consecutive patients were admitted to our hospital due to acute MI. These patients were divided into 2 groups according to the presence or absence of prior MI. Both groups were further divided according to the presence or absence of previous angina. The causes of in-hospital deaths were classified into 4 categories: (1) cardiogenic shock or congestive heart failure, (2) cardiac rupture, (3) arrhythmia, and (4) other causes. In patients with a first MI, the in-hospital mortality rate was lower in patients with previous angina than those without (6.9% vs 11.4%, p <0.01). There was no significant difference between these patients with and without previous angina in in-hospital deaths due to cardiogenic shock or congestive heart failure, arrhythmia, or other causes. Death due to cardiac rupture was less frequent in patients with previous angina (1.4% vs 5.0%, p <0.01). In patients with prior MI, the in-hospital mortality rate was lower in patients with than without previous angina (17.7% vs 25.3%, p <0.05). In contrast to patients with their first MI, there was a trend toward a lower incidence of in-hospital death due to cardiogenic shock or congestive heart failure in patients with previous angina (12.8% vs 19.0%, p = 0.05). There were no significant differences in in-hospital deaths due to cardiac rupture, arrhythmia, and other causes between the 2 subgroups. In multivariate analysis, previous angina was an independent predictor of in-hospital death. Thus, in-hospital deaths after acute MI in patients with previous angina were less because of less cardiac rupture in patients with a first MI and less cardiogenic shock or congestive heart failure in patients with prior MI.

Aged↗
PubMed1998

Correlation of residual stenosis immediately after coronary angioplasty with long-term prognosis.

This study evaluated the correlation of residual stenosis after percutaneous transluminal coronary angioplasty with the long-term prognosis. Among consecutive 1,230 patients who underwent coronary angioplasty in the National Cardiovascular Center in Osaka, Japan, 894 patients had de novo lesions. Of these, the 70 patients with acute myocardial infarctions and 105 with unstable angina who had emergency coronary angioplasties were excluded from the study. Among the remaining 719 patients, successful dilatation of the main target vessel was achieved in 592 patients, who then comprised the study group. They were divided into three groups according to their residual stenosis (RS) immediately after coronary angioplasty: group A, RS < 15% (n=208); group B, 15% < or = RS < or = 35% (n=286), and group C, 35% < RS < 50% (n=98). The duration of follow-up was 1,668, 1,660, and 1,680 days in group A, B, and C, respectively. The groups A, B, and C were not significantly different in terms of age, history of myocardial infarction, left ventricular ejection fraction, number of diseased vessels and target vessels, and risk factors such as hypertension, hyperlipidemia, and diabetes mellitus. Primary end point of follow-up was defined as death from any cause and the second end point was occurrence of cardiac events. Kaplan-Meier survival analysis showed significant differences among the three groups. Moreover, survival curves seem to be dependent on the degree of post-procedural residual stenosis. Multivariate analysis using a Cox proportional hazard regression model showed that age, ejection fraction, and residual stenosis were independent determinants of event-free, cardiac, and total survival. Residual stenosis immediately after coronary angioplasty is an independent contributor to long-term clinical prognosis in patients treated with successful balloon coronary angioplasty.

Analysis of Variance↗
PubMed1998

A new congenital muscular dystrophy with mitochondrial structural abnormalities.

We report a new form of congenital muscular dystrophy (CMD) in 4 patients from three unrelated families with probable autosomal-recessive inheritance. All patients had the clinical characteristics of merosin-positive congenital muscular dystrophy, but had marked mental retardation. The disease was slowly progressive and 1 patient died from dilated cardiomyopathy at the age of 13 years. In addition to dystrophic changes with necrosis and regeneration in muscle, the most striking finding was mitochondrial depletion in the center of the sarcoplasm. Mitochondria at the periphery of fibers were markedly enlarged ("megaconial" appearance) with complicated cristae, and contained a normal amount of mitochondrial DNA by in situ hybridization. Mitochondrial enlargement may represent functional compensation for mitochondrial depletion in the central sarcoplasm, where myofibrillar degeneration occurred.

Adolescent↗
PubMed1998

Quality evaluation by capillary electrophoresis of amphotericin B injection after filtration through various membrane filters.

The determination of amphotericin B, an antifungal agent, was developed using micellar electrokinetic capillary chromatography (MEKC) with a diode array detector. Repeatability and intermediate precision of MEKC analysis were acceptable. A high correlation was found between amphotericin B levels in pharmaceutical solutions obtained by MEKC and those by high-performance liquid chromatography (HPLC) (r = 0.994). This MEKC method is therefore useful for the determination of amphotericin B. The concentration of amphotericin B did not significantly change after filtration through polyethersulfone (PES, 0.2 microm) and polyvinylidene difluoride (PVDF, 0.45 microm) membrane filters. When the Fungizone injection was filtered through PES (0.2 microm) and added to 5% dextrose for injection (500 mL), particulate matters larger than 10 microm decreased by 64% to a level under the standard defined by United States Pharmacopoeia (USP XXIII). PVDF filtration (0.45 microm) did not have this effect. Our results suggest that filtration of Fungizone injection through PES (0.2 microm) membrane filters is recommended for the preparation of intravenous amphotericin B fluid.

Amphotericin B↗
PubMed1998

Relations between surface expression of the interleukin-2 receptor and release of the soluble form of the receptor in cultured mononuclear cells from patients with rheumatoid arthritis or systemic lupus erythematosus.

The relationship between surface expression of the interleukin-2 receptor (IL-2R) and release of the soluble form of the receptor (sIL-2Ralpha or sCD25) was investigated with peripheral blood mononuclear cells (PBMCs) from individuals with rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE). The spontaneous release of sCD25 was significantly increased in PBMCs from RA patients and decreased in cells from SLE patients, compared with normal controls. However, the extent of sCD25 release from phytohaemagglutinin (PHA)-stimulated PBMCs did not differ between RA or SLE patients and normal controls. The serum concentration of sCD25 was significantly increased in SLE or RA patients compared with the normal controls. Whereas the surface expression of CD25 by unstimulated PBMCs did not differ among the three groups of subjects, this parameter was significantly reduced for PHA-stimulated PBMCs from RA patients relative to those from normal controls. The surface expression of CD25 showed a positive correlation with sCD25 release for PBMCs from SLE patients under either basal or stimulated conditions. No such relation was apparent for cells from RA patients. The surface expression of IL-2Rbeta (CD 122) under basal or stimulated conditions was significantly reduced in PBMCs from RA or SLE patients, compared with cells from normal controls. Thus, the increased concentration of sCD25 in the serum of individuals with these autoimmune rheumatic diseases may result from two different mechanisms: an increase in the spontaneous release of sCD25 in RA, and reduced clearance of this protein in SLE.

Adult↗
PubMed1998

Desmoplastic response in biopsy specimens of early colorectal carcinoma is predictive of deep submucosal invasion.

PURPOSE: The aim of this study was to evaluate the role of histopathology of biopsy specimens in predicting depth of infiltration in early colorectal carcinomas before treatment. METHODS: Early colorectal carcinomas that had been resected surgically or endoscopically between 1984 and 1995 were analyzed. Histopathologic findings, including differentiation of adenocarcinoma and a desmoplastic response were investigated. RESULTS: One hundred nine early colorectal carcinomas consisted of 73 lesions of carcinoma in situ, 13 submucosal carcinomas with minimum invasion, 8 lesions with moderate invasion, and 15 lesions with deep invasion. Of 73 carcinoma in situ lesions, 72 (approximately 99 percent) showed well-differentiated adenocarcinomas and no desmoplastic response. Twelve (92 percent) of 13 submucosal carcinomas with minimum invasion also revealed well-differentiated adenocarcinoma without a desmoplastic response. Sixty-three percent (5/8) of lesions with moderate invasion revealed well-differentiated adenocarcinoma. None of the lesions had a desmoplastic response. Among lesions with deep invasion, 73 percent (11/15) demonstrated moderately differentiated adenocarcinoma, and 11 lesions had a prominent desmoplastic response (73 percent; P < 0.01). CONCLUSIONS: These results suggest that if histopathologic findings of biopsy specimens taken from them before treatment demonstrated adenocarcinoma associated with a desmoplastic response, the lesions had at least deep invasion carcinomas. These lesions should be resected surgically. Submucosal carcinomas with minimum invasion, which have no desmoplastic response, could be treated endoscopically.

Adenocarcinoma↗
PubMed1998

Hypoproteinemia caused by tricuspid regurgitation: report of a case.

A case of tricuspid regurgitation (TR) complicated by severe hypoproteinemia is presented herein. A 68-year-old man who had undergone coronary artery bypass grafting (CABG) for postinfarction angina suffered repeated inferior myocardial infarction due to obstruction of the proximal right coronary artery, 3 years after which he developed systemic edema. Investigations revealed TR associated with hypoproteinemia; however, treatment consisting of aggressive diuretic therapy and albumin administration proved ineffective. The hypoproteinemia manifested as protein-losing enteropathy clinically, and the tricuspid valve was replaced to eliminate high venous pressure. The serum protein levels became normalized after the operation. Although TR is generally well tolerated in the absence of pulmonary hypertension, surgical management is recommended for patients with severe protein deficiency resistant to medical treatment.

Aged↗
PubMed1998

Halofuginone inhibits neointimal formation of cultured rat aorta in a concentration-dependent fashion in vitro.

Halofuginone, an anticoccidial quinoazolinone, can specifically inhibit collagen type alpha1 (I) synthesis and gene expression, and also inhibits cultured smooth muscle cell proliferation. The aim of this study was to investigate the effect of halofuginone on neointimal formation of rat aorta after culture in a concentration-dependent manner in vitro. Thoracic aorta of Wistar rats was removed and manipulated to damage the endothelium under sterile conditions, and culture for 15 days in halofuginone-free or halofuginone-added culture medium (n = 20). Segments of cultured aorta were studied by histologic and immunohistochemical methods. Proliferation of neointimal layers consisting of loose multilayer cellular structure was observed in the halofuginone-free control group after 15 days of rat aorta culture, and neointimal formation was significantly decreased as an increasing concentration of halofuginone was added. As with precultured fresh aorta, no intimal proliferation was observed in the cultured segments of aorta with 500 ng/ml halofuginone added to culture medium. The proliferation of cell nuclear antigen index was significantly higher in the halofuginone-free control group than that in the halofuginone-added groups. The present results suggest that halofuginone can inhibit neointimal formation of rat aorta after culture in a concentration-dependent fashion in vitro.

Animals↗
PubMed1998

Endotracheal administration of lidocaine inhibits isoflurane-induced tachycardia.

PURPOSE: Rapid increase in inspired isoflurane concentration increases heart rate and arterial blood pressure. To investigate whether the responses to isoflurane were elicited from stimulation of lower airway and/or lungs, haemodynamic responses to isoflurane administered after tracheal intubation were measured with or without endotracheal or intravenous administration of lidocaine. METHODS: Seventy-two ASA physical status 1 patients, aged 21-50 yr, were randomly allocated to one of four groups. After tracheal intubation, anaesthesia was maintained with oxygen 100% and isoflurane 1.0% with controlled ventilation. After stabilization for 15 min, the isoflurane concentration was rapidly increased to 3.0% in three groups. An endotracheal lidocaine group received pretreatment with endotracheal 0.4 ml lidocaine 8% spray, an intravenous lidocaine group received pretreatment of 32 mg lidocaine i.v., and an isoflurane 3% group received not pre- treatment. In a control group, inspired isoflurane concentration was maintained at 1.0%. Heart rate, systolic blood pressure and end-tidal isoflurane concentration were measured every minute for 10 min. RESULTS: The rapid increase in isoflurane concentration increased heart rate (25 +/- 12% increase from baseline; P < 0.05) but the increase was reduced by endotracheal lidocaine (9 +/- 9%), but not by intravenous lidocaine (22 +/- 13%). The plasma concentration of lidocaine was lower in the endotracheal lidocaine group (0.4 +/- 0.3 microgram.ml-1) than in the i.v. lidocaine group (1.5 +/- 0.2 micrograms.ml-1). CONCLUSION: The isoflurane-induced tachycardia is reduced by pre-treatment with endotracheal lidocaine.

Administration, Inhalation↗
PubMed1998

Potential for qualitative diagnosis of tumors and tumorous lesions in the liver with Tc-99m-GSA SPECT--correlation with pathological evaluation and MRI findings.

To evaluate the effect of technetium-99m-labeled DTPA-galactosyl human serum albumin (Tc-99m-GSA) SPECT imaging for qualitative diagnosis of hepatic lesions. The subjects were 29 patients with pathologically confirmed hepatic lesions (21 malignant and 8 benign lesions). SPECT data were obtained at about 30 minutes after injecting 185 MBq (5 mCi) of Tc-99m-GSA. The GSA SPECT findings were compared with those of pathological evaluation and T2-weighted MR images (T2WI). Of 29 lesions, 17 showed decreased accumulation, and three exhibited increased accumulation. The other nine lesions were undetectable. The malignant lesions which showed increased accumulation were all well differentiated hepatocellular carcinomas (HCCs). One of the eight benign lesions exhibited increased accumulation. The three lesions which showed increased accumulation of GSA exhibited hypointensity on T2WI, whereas the malignant lesions which showed decreased accumulation of GSA exhibited hyperintensity on T2WI. The GSA SPECT findings correlate well with those of T2WI. GSA SPECT may be useful for qualitative diagnosis of focal liver lesions. If a lesion is suspected of being HCC, increased accumulation may indicate well differentiated HCC.

Adenocarcinoma↗
PubMed1998

An effective method for improving hemostasis in aortic root replacement with a composite graft.

Hemostasis during aortic root replacement with a composite graft, consisting of a separate Dacron graft and a valve, was markedly improved by using a supra-annular aortic wall reinforcing suture (SAWR). Between February 1994 and January 1998, 14 consecutive patients (10 men and 4 women) underwent replacement of the aortic valve and ascending aorta with the SAWR technique. No intraoperative bleeding of the aortic proximal suture line or early death occurred in this group. No patient required reoperation for bleeding of anastomoses. Three of 10 patients who underwent elective operations were operated on successfully without blood transfusion. In addition, no clinical complications related to the SAWR technique were observed in the follow-up period. We conclude that the SAWR technique can be performed easily and may be an effective method for improving proximal hemostasis.

Aortic Dissection↗
PubMed1998

Advanced glycation end products co-localized with astrocytes and microglial cells in Alzheimer's disease brain.

In the previous study [Takeda et al. (1996) Neurosci Lett 221: 17-21], we reported that the advanced glycation end products (AGEs) in the external space of neuronal perikarya (extraneuroperikaryal AGE deposits) were significantly abundant in the Alzheimer's brain. In this study, we investigated the spatial relationship of the extraneuroperikaryal AGE (carboxymethyllysine and pentosidine) deposits in astrocytes and microglial cells in the Alzheimer's disease brain using double immunolabelling for AGEs and astrocyte or microglial cell markers. Most of the extraneuroperikaryal AGE deposits were co-localized with glial fibrillary acidic protein-positive astrocytes. AGE deposit-bearing astrocytes also contained Gomori-positive granules. Furthermore, some of the extraneuroperikaryal AGE deposits were co-localized with microglial cells. These extraneuroperikaryal AGEs may activate astrocyte and microglia, and play a role in pathogenesis of Alzheimer's disease.

Aged↗