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Biomedical subjects

S Endo

Publications and source records attributed to S Endo.

At least 505 records · Page 28Linked to original sources
PubMed1991

Differences in critical cerebral blood flow with age in swine.

Normal cerebral blood flow (CBF), critical CBF at a flat reading of the electroencephalogram (EEG), and reversibility of the flat EEG after reperfusion were investigated in a total of 59 pigs, including seven newborns (1 to 3 days of age), 38 juveniles (1 month old), and 14 adults (7 months old). The CBF was determined by the hydrogen clearance method; the EEG was recorded continuously and a power spectrum analysis was performed. Cerebral ischemia was produced by occlusion of both common carotid arteries and induction of hypotension (approximately 50 mm Hg). The flat EEG reversibility was investigated for 3 hours after reperfusion. As parameters of brain development, the neuronal density and the time at which the S-100 protein appeared in the brain were examined. Normal CBF was highest in neonatal pigs and decreased with age. The critical CBF at a flat EEG was lowest in newborn pigs and was elevated with development of the brain. Tolerance against cerebral ischemia was greatest in newborn pigs.

Aging↗
PubMed1991

[Deformation of brain and stress distribution caused by putaminal hemorrhage--numerical computer simulation by finite element method].

Deformation and stress distribution caused by putaminal hemorrhage in two-dimensional model brain were analyzed by computer simulation using finite element method. The model brain was composed of cerebral cortex, white matter, caudate nucleus, lenticular nucleus, thalamus and lateral ventricle. Young's modulus of gray and white matter was assumed to be 0.08 and 0.04 kgf/cm2, respectively, and Poisson's ratio was 0.47 for both of them. Bleeding of 100 mmHg pressure was represented by 4 vectors of force directing anterior, lateral, posterior and medial direction from the middle portion of putamen. Calculation of finite element method was carried out by a 16-bit personal computer. The calculated deformation of brain presented a hematoma cavity elongated from anterior to posterior direction at the lenticular nucleus. Mass effect of hematoma was noted from displacement of the anterior horn of the lateral ventricle and the internal capsule. Distribution of stress vector revealed the stress concentration at the lenticular nucleus while small stress was noted all over the model brain. Strength of principal stress was presented by contour-line and took the shape of concentric circles with a center at the putamen. This study suggested that the computer simulation by finite element method would be a useful technique to analyze the physical phenomenon of brain suffered from intracerebral hemorrhage.

Basal Ganglia Diseases↗
PubMed1991

Genetic studies of febrile convulsions: analysis of twin and family data.

Children with febrile convulsions (FC) including 46 twin pairs, 1913 families including 393 sibling pairs, and 42 three-generation FC kindreds have been studied. Twin studies: (1) The pairwise concordance rate for FC was 69% (18/26 pairs) in monozygotic (MZ) and 20% (4/20 pairs) in dizygotic (DZ) twins (P less than 0.01). (2) The intra-pair similarity of clinical symptoms in 18 concordant MZ twin pairs showed a positive significant correlation, particularly in 4 items--duration of seizure, exogenous factors, intelligence level, and background EEG abnormality. These correlations were greater than those in sibling pairs. (3) No evident cause for discordance was detected in 8 discordant MZ twin pairs, and many dissimilar symptoms were observed in 4 concordant DZ twin pairs. Sibship studies: A large positive correlation of some clinical symptoms was observed in sibling pairs concordant for FC: age at onset of FC, degree of fever, duration of seizure, exogenous factors, and background EEG abnormality (r = +0.2- +0.6). Family history analysis: Morbidity risk among near relatives (17% in parents, 23% in siblings) than in second- (6.1%) or third-degree relatives (4.6%). The difference was found between: sibling greater than parents, uncles greater than aunts, male cousins greater than female cousins. Segregation analysis showed maternal preponderance. In 42 three-generation kindreds the morbidity risk was higher in siblings (32%), uncles/aunts (14%), and cousins (6.4%) than in relatives of other probands. Characteristic findings in FC patients with family history: Characteristic findings in FC patients with an FC parent or sibling, compared with those with no family history, were early onset of FC, lower degree of fever, longer duration of seizure, many recurrences, FC recurrence after age 3, and background EEG abnormality. Similar findings were more markedly observed in 42 3-generation kindreds. Mode of inheritance: A multifactorial mode of inheritance for FC receives some support from this study, and the heritability was estimated as 75%.

Child, Preschool↗
PubMed1991

[An experimental study on portal infusion of 5-fluorouracil].

We conducted these experiments to investigate the differences between continuous portal and one shot portal infusion of 5-fluorouracil (5-FU) using male Donryu rats. Continuous portal infusion of 5-FU (20 mg/kg/day x 5 days) revealed no remarkable side effects on the rats with significant decrease in the number of liver metastases generated by intraportal inoculation of ascites hepatoma AH60C. Consecutive 5-day administration of 5-FU (20 mg/kg x 5) by one shot method via spleen resulted in no metastases but caused death in 75% of rats because of severe leukopenia and dehydration. The rats receiving one shot infusion of 5-FU (33.3 mg/kg x 3, day 1, 3, 5) via spleen showed a significant decrease in the number of metastases without lethal side effects. Continuous portal infusion of 5-FU would be a safe and effective therapy to prevent liver metastases, whereas one shot portal infusion of 5-FU may give rise to severe side effects while preventing liver metastases.

Animals↗
PubMed1991

[A successful surgical treatment of cor triatriatum with VSD, PDA and CoA].

A successful repair of cor triatriatum with VSD, PDA and CoA is reported. A two-month-old boy was admitted for evaluation of growth failure and cyanosis. Physical examination on admission revealed systolic murmurs at left sternal border. Chest X-ray showed increased pulmonary vascularities without cardiomegaly. Echocardiography showed abnormal wall in left atrium with VSD, PDA and CoA. An emergency operation consisting of patch closure of VSD, ligation of PDA and resection of the anomalous left atrial membrane were performed. At postoperative course, an episode of pulmonary hypertension crisis happened. But the patient tolerated this episode and survived.

Aortic Coarctation↗
PubMed1990

Microcystin-LR, a potent protein phosphatase inhibitor, prolongs the serotonin- and cAMP-induced currents in sensory neurons of Aplysia californica.

Microcystin-LR (MCYST-LR), a hepatotoxin produced by cyanobacteria, inhibited purified protein phosphatases (PrPs) from rabbit skeletal muscle and the enzymes from Aplysia with an IC50 of approximately 10(-10) M. MCYST-LR also prolonged both serotonin- (5-HT) and cyclic adenosine monophosphate-induced inward currents in sensory neurons of Aplysia. These results, which are consistent with inhibition of Aplysia PrPs, indicate that MCYST-LR may be a useful probe to elucidate the function of PrPs in neural tissues.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1990

Conformation in solution of porcine brain natriuretic peptide determined by combined use of nuclear magnetic resonance and distance geometry.

The conformation in solution of porcine brain natriuretic peptide was determined by combined use of NMR spectroscopy and distance geometry. A set of 157 inter-proton-distance constraints was derived from the two-dimensional NOE spectra, and further a set of three hydrogen bond constraints was obtained from analysis of the temperature dependence of labile protons. The five structures with minimal violations were selected after performing distance-geometry calculations starting from 40 random initial conformations. The distance-geometry structures were further refined by the use of restrained energy minimization and restrained molecular dynamics. This structure shows a compact conformation with the carboxy-terminal region, Asn21-Tyr26, folded back to the disulfide-linked loop region, Cys4-Cys20. The characteristics of the conformation determined are as follows: conformations of the three segments interposed by glycine residues, which are Arg7-Ile12, Ser14-Leu18 and Cys20-Arg25, were well defined and the segments Arg7-Ile12 and Cys20-Arg25 are rather close to each other and nearly parallel. The biological significance of these local conformations is discussed on the basis of comparisons with those of atrial natriuretic peptide reported by Kobayashi et al.

Amino Acid Sequence↗
PubMed1990

The mitotic apparatus-associated 51-kDa protein from sea urchin eggs is a GTP-binding protein and is immunologically related to yeast polypeptide elongation factor 1 alpha.

We investigated the biochemical characteristics of the 51-kDa protein that is a major mitotic apparatus-associated basic protein of sea urchin eggs (Toriyama, M., Ohta, K., Endo, S., and Sakai, H. (1988) Cell Motil. Cytoskeleton 9, 117-128). The amino acid composition of the 51-kDa protein was apparently different from those of tubulin, actin, histones, and myelin basic protein; yet it was similar to those of polypeptide elongation factors 1 alpha (EF-1 alpha). In addition, antibody to EF-1 alpha from yeast cross-reacted with the 51-kDa protein. [3H] GTP binding activity was detected in the phosphocellulose-purified fraction (PC fraction) which predominantly contained the 51-kDa protein and was shown to be specific to GTP, GDP, guanylyl imidodiphosphate, and ITP. Photo-affinity labeling using [alpha-32P]8-azidoguanosine triphosphate (8-azido-GTP) demonstrated that a 51-kDa polypeptide in the PC fraction specifically bound 8-azido-GTP. This GTP-binding polypeptide was bound to a GTP affinity column, could be eluted by the addition of GTP, and was immunoreactive with anti-51-kDa protein antibodies. When the PC fraction was applied to a gel filtration chromatography column, GTP binding activity was completely coeluted with the 51-kDa protein. Furthermore, the PC fraction and the gel filtration-purified fraction had EF-1 alpha activity: [14C]Phe-tRNA transferring activity to ribosomes in the presence of poly(U) and ribosome-dependent GTPase activity. The results indicate that the mitotic apparatus-associated 51-kDa protein is a GTP-binding protein and suggest that it is structurally and functionally related to yeast EF-1 alpha.

Affinity Labels↗
PubMed1990

Nonrandom chromosome alterations that correlate with progression to immortality in rat tracheal epithelial cells transformed with N-methyl-N'-nitro-N-nitrosoguanidine.

Primary rat tracheal epithelial cells can be transformed in vitro by N-methyl-N'-nitro-N-nitrosoguanidine. The earliest recognizable morphological transformant is the enhanced growth variant (EGV), characterized by enhanced proliferative capacity. Transformed EGV colonies can progress to give rise to immortal cell lines. The purpose of this study was to determine if specific chromosome changes occur which correlate with immortalization. A total of 34 EGV colonies were isolated, of which five were able to progress in culture to become immortal (greater than or equal to 100 population doublings). Early passages of all five immortalized cultures exhibited additional copies of chromosomes 4, 7, and 11 as a common or recurrent abnormality. These numerical alterations were rarely observed in the primary EGV colonies from which the cell lines were derived, suggesting that these alterations occurred during progression. Structural alterations involving chromosome 1 (resulting in a net gain of 1q) and chromosome 3(3q) also occurred in four out of five immortalized cultures. In all cases, structural alterations involving 1q and/or 3q were detected in the primary EGV colonies from which the immortal cell lines arose. Comparison of the frequency of the structural and numerical alterations observed in the immortalized cultures with their frequency in the 29 EGV colonies which did not become immortal indicated that these changes correlated (P less than or equal to 0.005) with the ability to become immortal. These results suggest that structural alterations occur in primary EGV colonies which predispose cells to immortalization and that subsequent numerical changes occur during progression that correlate with acquisition of the immortal phenotype.

Aneuploidy↗
PubMed1990

Proton nuclear magnetic resonance studies of the structure of the Fc fragment of human immunoglobulin G1: comparisons of native and recombinant proteins.

The structure of the Fc fragment of human IgG1 immunoglobulin is compared for the native and recombinant proteins. A recombinant human Fc fragment was expressed by an E. coli system [Kitai K., Kudo T., Nakamura S., Masegi T., Ichikawa Y. and Horikoshi K. (1988) Appl. Microbiol. Biotechnol. 28, 52-56]. The recombinant protein, which presumably lacks oligosaccharides, was used along with the native human Fc fragment obtained by proteolytic digestion of a myeloma IgG1 protein. 1H NMR has been employed along with circular dichroism and fluorescence spectroscopy to discuss the structure of these two types of proteins. It has been concluded that (1) the overall structure of the recombinant protein is quite similar to that of the native protein, which possesses asparagine-linked oligosaccharides, but (2) a significant difference in structure exists in the neighborhood of the glycosylation site. The difference in the effector functions for the two kinds of the Fc proteins has been briefly discussed in terms of the structural change detected by 1H NMR.

Amino Acid Sequence↗
PubMed1990

Surgical approach to arteriovenous malformation of the medial temporal lobe--report of three cases.

We report three cases of arteriovenous malformation (AVM) of the medial temporal lobe and the surgical approaches used. The AVM was fed by the anterior choroidal artery (AChA) in two cases (Cases 1 and 2) and by the posterior cerebral artery in one (Case 3). The trans-Sylvian approach was first used for cerebrospinal fluid aspiration to retract the brain in all cases, and for confirming the feeding arteries to prevent premature bleeding from the AVM in Cases 1 and 2. In Case 1, a corticotomy was then made in the fusiform gyrus via the subtemporal approach to avoid the development of speech disturbance and visual field defects, while in Cases 2 and 3, a cortical incision was made in the middle temporal gyrus because visual field defects were preoperatively present. Cases 1 and 2 achieved good recoveries, but Case 3 suffered postoperative speech disturbance and died of rebleeding from a recurrent AVM fed by the AChA 22 months after the operation. This AVM was not demonstrated on the postoperative angiograms. We emphasize the usefulness of the combination of trans-Sylvian and subtemporal approaches for this lesion, because the feeding arteries are easily identified and retraction of the temporal lobe is alleviated. A corticotomy in the fusiform gyrus is also recommended to avoid the development of not only visual field defects but also aphasia.

Adolescent↗
PubMed1990

[A case of progressive systemic sclerosis with Sjögren's syndrome complicated by nephrotic syndrome caused by bucillamine].

A 53-year-old woman was admitted with complaints of edema in the lower legs. The patient had developed polyarthralgia in 1982 and had been treated with D-penicillamine and prednisolone under the diagnosis of rheumatoid arthritis. She then had developed sclerosis of skin as well as dry eyes and dry mouth. In November 1987, bucillamine treatment had started and proteinuria had appeared in February 1988. Her blood showed hypoproteinemia and was positive for anti-Scl-70 antibody test and for anti-SS-A antibody test. The skin biopsy and labial salivary gland biopsy revealed the increased collagen fibers in the subcutaneous tissue and the round cell infiltration around the salivary ducts. We diagnosed her as progressive systemic sclerosis (PSS) with Sjögren's syndrome (SjS) complicated by nephrotic syndrome. Subsequently a renal biopsy was performed. There were the granular deposition of IgG and complements in the glomerular capillary wall and electron dense deposits in the subepithelial region. These findings suggested that she had membranous nephropathy. Since such a renal lesion was rarely observed in PSS and SjS, it was highly probable that bucillamine induced the nephropathy. The bucillamine treatment was discontinued about 2 months after the nephrotic syndrome had developed. However, the nephrotic syndrome has continued for additional 8 months. Thus it is concluded that the renal damage is one of the important side effect caused by bucillamine.

Anti-Inflammatory Agents, Non-Steroidal↗