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Biomedical subjects

S Nishida

Publications and source records attributed to S Nishida.

At least 325 records · Page 18Linked to original sources
PubMed1986

A morphological study on the effects of collagen gel matrix on regeneration of severed rat sciatic nerve in silicone tubes.

The present study is a chronological morphological examination on the effects of collagen gel matrix on regeneration of severed sciatic nerves. The nerves (5 mm length) were resected, and both the distal and proximal stumps were inserted into a silicone tube with 5 mm gap in between. In the test side, the gap in the tube was then injected with liquid collagen which gels in the tissue when reconstructed with a certain buffer solution. The gap space in the tube of the control side was left empty. In a chronological examination of the tissue in the tube, considerably more rapid growth of sprouting axons toward the distal stump in the test side was revealed in comparison with the control side. The cells, including both fibroblasts and larger Schwann cells, were less in number. More orderly directions were observed in the collagen matrix than in the control tube. The result indicates that regeneration of the peripheral nerves in the silicone tube can be improved, by using appropriate exogenous fine materials, collagen matrix.

Animals↗
PubMed1986

Immunohistochemical reaction of myocardial fibers with actin antiserum in autopsy cases of myocardial infarction.

The purpose of this study was to determine the immunoreactivity of myocardial actin filaments with actin antiserum and to examine the significance of its application to diseased human cardiac muscle. The actin was extracted and purified from chicken gizzards. Anti-actin rabbit serum was prepared and purified by affinity chromatography and defined by an immunoblotting test. Using the avidin-biotin-peroxidase complex (ABC) method, the actin antiserum was applied to paraffin sections prepared from hearts taken from routine autopsies of patients who had died of myocardial infarction. Reactivity was shown to be completely lost, not only in necrotized fibers, but also in non-specific degenerative fibers which could be identified by their eosinophilic cytoplasm with pyknotic nuclei, and clearly remaining and/or diminished cross-striations stained with hematoxylin-eosin. In contrast, hypertrophic myocardial fibers adjacent to granulation or scar tissue and those adjacent to infarcted foci exhibited a more intense reaction. These results indicated that the immunohistochemical reaction of actin filaments can be used for the easy detection of very mild degrees of degeneration of cardial muscle fibers, and for hypertrophic fibers adjacent to diseased foci. Studies of the immunoreactivity of actin protein suggestive of alteration at the molecular level might yield morphological clues regarding the nature of functional activity in the contraction of cardiac fibers.

Actins↗
PubMed1986

Experimental study of WGA binding on the endothelial cell surface in cerebral ischemia.

The relationship between the saccharide chain on the endothelial cell surface and the permeability of intracerebral blood vessels has been studied. In the present study, wheat germ agglutinin (WGA) was perfused into capillaries in the area postrema of the normal Mongolian gerbil, where the blood brain barrier (BBB) is known to lack, and into intracerebral blood vessels, the BBB of which had been destroyed by experimentally induced brain ischemia. The light microscopic features of the sections from WGA-perfused brain tissues of the normal gerbil revealed that most of the blood vessels, including capillaries in the brain parenchyma, showed positive findings (the reaction induced a very distinct staining of the vascular wall) from which the course and structure of the fine vessels could be determined. The reaction to WGA on the diaphragma fenestra (DF) in capillaries in the area postrema was relatively weak, and DF without the reaction were occasionally revealed by electron microscopy. The gerbil, in which cerebral ischemia had been induced, also showed partial defect of the reaction with WGA on the luminal side of the endothelial cells. The results of the present experiment suggest some degree of correlation between the saccharide chains, including the specific monosaccharide of WGA, on the endothelial cell surface and permeability. It was considered that lectin can be used as an index for morphological observations, suggesting an alteration in function of the endothelial cell membrane. In addition, the perfusion method in this experiment suggested the possibility of distinguishing pinocytotic vesicles from pits of cell membranes.

Acetylglucosaminidase↗
PubMed1986

Lectin (UEA-1) reaction of capillary endothelium with reference to permeability in autopsied cases of cerebral infarction.

The relationship between endothelial reactivity to Ulex europaeus agglutinin-1 (UEA-1) and the permeability of the vascular wall in human autopsied cases of cerebral infarction was studied. Sections from the cerebral cortex were reacted with horseradish peroxidase UEA-1 to demonstrate the surface membrane of endothelial cells. Albumin in the neuropil of sections was demonstrated for the estimation of increased vascular permeability. The results showed that endothelial reactivity to UEA-1 was reduced in cases where death had occurred 3 to 5 days after onset of cerebral infarction. Reactivity was also diminished in cases where death had occurred after 13 and 25 days; these cases showed fresh ischemic lesions caused by re-attacks of infarction. Albumin extravasation into the neuropil was demonstrated in these intermediate cases. Chronic cases, dying after more than 52 days, showed no reduction of endothelial reactivity to UEA-1 and no albumin extravasation was proved. It was concluded that UEA-1 can be employed as a useful morphological marker for evaluation of endothelial function and vascular permeability.

Aged↗
PubMed1986

[Two cases of intussusception of appendiceal mucocele: diagnostic value of preoperative ultrasonography].

Mucocele of the appendix was first described and named "Hydrops processus vermiformis" by Rokitansky in 1866. Intussusception of a appendiceal mucocele is very rare and we have been able to find only 14 previously reported cases. We present two cases with preoperative ultrasonography which is valuable for its diagnosis. Case 1: A 5-year-old male was admitted to Kahoku Hospital because of right lateral colic abdominal pain and tumor. Ba-enema examination revealed intussusception to the colon and ultrasonography showed the cystic mass of the appendix. Case 2: A 51-year-old female was admitted because of right lower abdominal pain. Ultrasonography was helpful showing the cystic tumor at the base of the appendix. Recent reports say that ultrasonography is valuable examination for its diagnosis. Also in our two cases preoperative ultrasonography was performed and gave us valid information for its qualitative diagnosis.

Appendix↗
PubMed1986

Scanning electron microscopy of ciliary muscle of monkey eye.

The three-dimensional structure of the ciliary muscles of the cynomolgus monkey eye was studied by scanning electron microscopy after the treatment of the muscle in 8 N hydrochloric acid. The meridional muscle bundles in the outer part of the ciliary body were closely arranged and multilayered, extending in a straight anteroposterior direction from its anterior tips to the distal terminal. The anterior part of the muscle bundles consisting of compactly associated small muscle bundles appeared to have a smooth surface and formed a broad belt partially covered by fibrocytes. The anterior tips of the muscle bundles were divided into slender bundles which were connected to the trabecular sheets. The distal terminal part of the muscle bundles tapered markedly in thickness and split into fine bundles resembling a brush, showing a firm fixation in the surrounding stroma of the ciliary body. In the anterior part of the ciliary muscle, the muscle bundles internally situated divided into two branches forming a Y-shape in their extension in the straight anteroposterior direction. The divided branches merged with the branches from other muscles of the same kind and formed muscle sheets with a reticular pattern separated by the stroma of the ciliary body. These adjacent muscle bundles were arranged occasionally like parquetry work, indicating that the sheets appeared to consist of oblique muscles in the meridionally sectioned specimen. In the present study paired tips of V-shape in the anterior part of both the meridional and oblique muscles were not observed. Beneath the obliquely extending muscle bundles, circumferentially arranged muscle bundles were observed, but the interconnection with the other two groups of the muscle bundles was not demonstrated.

Animals↗
PubMed1985

Amino acid sequence of a sea anemone toxin from Parasicyonis actinostoloides.

Amino-acid sequence of a toxin from sea anemone, Parasicyonis actinostoloides, is determined. The toxin consists of 31 amino acid residues and is cross-linked with four disulphide bridges. The sequence has some similarity to that of toxin III and no similarity to those of toxin I and toxin II both from sea anemone, Anemonia sulcata, or to that of Anthopleurin A from Anthopleura xanthogrammica.

Amino Acid Sequence↗
PubMed1985

New application of high-performance liquid chromatography for analysis of urinary C-peptide.

A successful application of high-performance liquid chromatography for analysis of urinary C-peptide is described. Samples (1.0 ml of human urine) were first subjected to gel chromatography to remove interfering substances, and then applied to a reversed-phase column (LiChrosorb RP-18, 7 micron). The detection of C-peptide was performed using a highly specific radioimmunoassay. With the newly developed techniques, at least four forms of immunoreactive C-peptide were detected in human urine. One of these peptides was indistinguishable from authentic C-peptide. The present study has clearly demonstrated the heterogeneity of urinary C-peptide.

Adult↗
PubMed1985

Insulin and C-peptide secretion from B cells in human subjects stimulated with glucose.

Two groups of immunoreactive insulin in human sera were reported by Kakita et al. (4), using gel chromatography after acid-alcohol extraction. These analogs were noted not only in circulating human sera but also in incubation medium and incubated human pancreas. The release of these insulin analogs was discussed in a previous report (5). The circulating C-peptide immunoreactivity was separated into two groups on a Bio-Gel column, and the early peak should not be proinsulin but an associated C peptide (6). These analogs of insulin were separated by the methods of ion-exchange chromatography, isoelectric focusing, gel electrophoresis, and gel chromatography. Immunoreactive insulin was also separated into two major bands by standard polyacrylamide gel electrophoresis. The fast migrating band corresponds to the rat insulin II position, and the slower corresponds to rat insulin I, which has one more basic amino acid residue in comparison with rat insulin II. Further studies have been performed in five healthy adults in order to elucidate the physiological relationship between analogs of insulin and C-peptide peak substances in human serum; the results are reported in this paper with a consideration of the mechanism of insulin secretion.

Adult↗
PubMed1985

Quantitative analysis of 'organization' by feature extraction of the EEG power spectrum.

Quantitative analysis of 'organization' of the background EEG activity was made by applying a new method of approximating the optimal intensity-fitting function to the EEG records of healthy college students. The parametric intensity-fitting function used in this study to approximate the power spectrum of EEG was a gaussian type function. Among the quantitative parameters obtained by the new method, the ratio of the integrated power of alpha rhythm to that of all rhythms and the standard deviation of the alpha frequency proved to be the most important organization parameters by inspecting the Pearson product-moment correlation coefficient. Next the automatic scoring of 'organization' was successfully performed by using the linear regression of those two organization parameters.

Adult↗
PubMed1985

Isolation and properties of two phospholipases A2 from the venom of an Australian elapid snake (Pseudechis australis).

Two phospholipases A2 (Pa-11 and Pa-13) were purified from the venom of an Australian elapid snake (subfamily Acanthophiinae) Pseudechis australis (king brown snake) by chromatography on CM-cellulose CM-52 followed by gel filtration on a Sephadex G-75 column. The apparent molecular weights of the two phospholipases A2 (Pa-11 and Pa-13) were 14,000 and 13,500, respectively, by gel filtration analysis on a Sephadex G-75 column. Each enzyme molecule consists of a single polypeptide chain of 118 amino acid residues. The isoelectric points of Pa-11 and Pa-13 were 10.5 and 10.0, respectively. The optimum pH values of Pa-11 and Pa-13 for hydrolysis of egg-yolk phosphatidylcholine were 7.8 and 7.5, respectively. Pa-11 was lethal to mice (LD50 0.23 micrograms/g body weight), whereas Pa-13 showed no lethal activity at a dose level of 7.4 micrograms/g mouse. Each enzyme was inactivated by reaction with p-bromophenacylbromide on the sole histidine residue (Pa-11) or on one of the two histidine residues (Pa-13). Oxidation of the tryptophan residues in Pa-11 and Pa-13 with N-bromosuccinimide led to a decrease in the phospholipase A activity. A complete loss of both enzymic and lethal activities of Pa-11 was observed upon oxidation of one of the two tryptophan residues of the molecule.

Acetophenones↗
PubMed1985

Amino acid sequences of phospholipases A2 from the venom of an Australian elapid snake (king brown snake, Pseudechis australis).

Two basic phospholipases A2 (Pa-11 and Pa-13) have been isolated from the venom of an Australian elapid snake, Pseudechis australis (king brown snake). The reduced and S-carboxymethylated phospholipases A2 were digested with trypsin and the resulting peptides were purified by a combination of chromatography on a DEAE-cellulose DE-52 column and gel filtration procedures. Eleven main peptides from Pa-11 and 9 peptides from Pa-13 could account for the amino acid compositions of the respective enzyme molecules. The alignment of the tryptic peptides and unelucidated regions of the amino acid sequences of tryptic peptides were established by the analysis of the peptides obtained by chymotryptic and/or Staphylococcal protease digestions. Each phospholipase A2 consisted of a single chain of 118 amino acid residues, including 14 half-cystine residues. Although Pa-11 is enzymatically 30-times as active as Pa-13 and highly toxic as compared to Pa-13, they are highly homologous in their amino acid sequences. They are also homologous to the enzymes from mammalian pancreas and the other snake venom phospholipases A2, especially to those from snakes belonging to the subfamilies Acanthophiinae and Laticaudinae.

Amides↗