Biomedical subjects

T Shin

Publications and source records attributed to T Shin.

At least 109 records · Page 6Linked to original sources

PubMed1995

Isolation and characterization of a novel 5-oxoprolinase (without ATP-hydrolyzing) from Alcaligenes faecalis N-38A.

A screening test was undertaken to isolate a microorganism that produced 5-oxoprolinase (without ATP-hydrolyzing). The 5-oxoprolinase (without ATP-hydrolyzing) activity (decyclization activity toward L-pyroglutamate) was found in a cell-free extract of Alcaligenes faecalis N-38A, newly isolated from a soil sample. The enzyme was purified as a homogeneous preparation. The molecular weight of the enzyme was estimated to be 47,000. The decyclization activity was specific for L-pyroglutamate, and independent of ATP and metal ions. The reaction was a reversible one, i.e., cyclization reaction of L-glutamate to yield pyroglutamate was identified.

Alcaligenes↗

PubMed1995

Morphologic study of the laryngeal taste buds in the cat.

The distribution of laryngeal taste buds (TBs) and their neutral components in the cat were investigated by immunohistochemistry and electron microscopy. The antisera used in this study were against cytokeratin, protein gene product 9.5 (PGP9.5), neuron-specific enolase (NSE), S-100 protein, calbindin D, calcitonin gene-related peptide (CGRP), and substance P (SP). Taste bud cells were specifically immunoreactive to the antibodies of human cytokeratin subtypes 8 and 18 (CAM5.2). On observation with CAM5.2, TBs were seen distributed on the laryngeal surface of the epiglottis and spread caudally along the aryepiglottic folds, reaching peak density at the laryngeal side of the arytenoid tubercle. The PGP9.5 and NSE immunoreactivities were recognized in TB cells and nerve fibers, both within the TBs and in the subepithelial connective tissue. S-100 protein immunoreactivities were not found in any of the cells in the TBs but were found exclusively in the subepithelial neural elements. The calbindin-D, CGRP, and SP immunoreactivities were confined to a part of the neural elements that was very thin. Taste pores, taste villi, neuronal varicosity, and synapselike structures were observed by scanning and transmission electron microscopic study. From these results it is considered that the TBs act as a chemical receptor.

Animals↗

PubMed1995

[Anesthesia for funnel chest operation].

The incidence of perioperative complication and days of hospital stay were studied in 56 patients with funnel chest operation under inhalational anesthesia (18 cases), intravenous anesthesia (23 cases) and epidural anesthesia (15 cases). Perioperative complication occurred most frequently in the inhalational group and was followed by intravenous and epidural group. Postoperative hospitalization on an average was 21.4 days in the inhalational group, 21.9 days in the intravenous group and 16.7 days in the epidural group. It is said that postoperative pain leads to splinting of the chest, which can cause atelectasis and/or pneumonia. Severe postoperative pulmonary complication was reduced in the epidural groups. As a result, hospitalization in the epidural group was shorter than in other groups. This study suggests that epidural anesthesia is more advantageous for funnel chest operation because epidural anesthesia has protective action against arrhythmia and postoperative pulmonary complication.

Adolescent↗

PubMed1994

Contact granulomas of the larynx.

Ten cases of intubation granulomas and eight cases of contact granulomas not related to intubation were reviewed for the purpose of clinical analysis and pathological investigation. Granulomas were located primarily at the vocal process of the arytenoid cartilage. Additionally, 58 hemilarynges obtained from 37 cadavers with intubation granulomas were evaluated grossly and histopathologically. The intubation granulomas had no side predilections. All eight contact granulomas occurred in males and had a higher incidence of recurrence (three of eight cases) despite complete removal with laser surgery. In an attempt to explain recurrences of these contact granulomas, all three cases were studied clinically and pathologically. Results indicated that they recurred in singers and vocal abusers, and presumably resulted from the continued hammering of one vocal process against the other. Analysis also demonstrated that vocal rehabilitation was essential prior to or immediately after removal of the granuloma to prevent its recurrence. Pathological evaluation of the contact granulomas revealed focal ulceration and a covering of necrotic tissue with desquamating epithelium. The propria mucosa was edematous and infiltrated by chronic inflammatory cells and neutrophils forming focal granulation tissue in a stroma containing proliferated capillaries. Pathological features around local ulcerations were typical of a secondary granuloma while underlying arytenoid cartilage was partially necrotic.

Adult↗

PubMed1994

Electron microscopic immunohistochemical study of intra-epithelial nerve fibers in the canine larynx.

Substance P (SP)-, calcitonin gene-related polypeptide (CGRP)-, and vasoactive intestinal polypeptide (VIP)-immunoreactive (IR) nerve fibers were observed in the epithelium of the canine subglottic region. To investigate the morphological differences among SP-, CGRP-, and VIP-IR nerve fibers in the epithelium, this study was performed by using immunohistochemical staining and electron microscopy, after which the origins of the nerve fibers were examined by denervation of the bilateral superior and inferior laryngeal nerves. SP- and CGRP-IR nerve fibers entered the epithelium through the basement membrane, ascended among the basal and ciliated cells, and reached under the epithelial junctional complex to terminate with varicosities. Furthermore, subsurface cistern-like structures or bouton en passant type synapse-like structures were observed among some varicosities of these nerve fibers and ciliated cells in the epithelial apical portion. On the other hand, VIP-IR nerve fibers entered through the basement membrane, and terminated with varicosities at the height of the middle portion of the subglottic epithelium. The varicosities of the VIP-IR nerve fibers were larger, and these varicosities had a greater number of synaptic vesicles than the SP- or CGRP-IR nerve fibers. After section of the bilateral superior and inferior laryngeal nerves, the SP- and CGRP-IR nerve fibers disappeared, while the VIP-IR nerve fibers were not affected. The density and distribution pattern of VIP-IR nerve fibers clearly differed from the SP- and CGRP-IR nerve fibers of sensory origin.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Studies on vocal fold injection and changes in pitch associated with alcohol intake.

The current study was carried out with particular emphasis on the association between phonetic function tests and alterations in the appearance of the hypopharyngeal and laryngeal mucosa, such as capillary dilatation, edema, and vocal fold injection after alcohol intake. The results demonstrated the occurrence of previously unrecognized pathophysiological changes associated with synchronous phonetic functions in the vocal pathway after alcohol intake. Serum ethanol and aldehyde concentration levels were evaluated hourly for 2.5 h after ingestion of alcohol. When an electronystagmogram showed the typical pattern of alcohol intake, the study was initiated. Occasionally, rhinography was performed on subjects complaining of a stuffy nose after alcohol intake.

Adult↗

PubMed1994

Characterization of ascorbate oxidase from Acremonium sp. HI-25.

The ascorbate oxidase obtained from a microorganism, Acremonium sp. HI-25 (molecular weight, 80 kDa; monomeric protein), was studied with respect to atomic absorption, EPR, absorption spectra, circular dichroism (CD) spectra, and steady-state kinetics. The enzyme was found to be a multicopper protein, containing four copper atoms of three kinds, types 1, 2, and 3 copper, in the ratio of 1:1:2. The EPR parameters of the type 1 and 2 copper atoms in the ascorbate oxidase are very similar to those in the case of the ascorbate oxidase obtained from cucumber, which is a dimeric protein. The apparent Km and kcat values for ascorbic acid of the ascorbate oxidase from Acremonium sp. HI-25 are almost the same as those of the monomeric unit of the ascorbate oxidase from cucumber.

Acremonium↗

PubMed1994

Differential expression of protein kinase C genes in cultured mast cells derived from normal and mast-cell-deficient mice and mast cell lines.

We investigated the expression of mRNA of protein kinase C (PKC) isozymes (alpha, beta, gamma, delta, epsilon, xi, and eta) in cultured mast cells (CMC) derived from normal (+/+) mice, CMC derived from genetically mast-cell-deficient (W/W, Wv/Wv, and mi/mi) mice, and murine mast cell lines (IC2, MC9, and P-815) by Northern blotting. In +/+ CMC, abundant expression of PKC delta and moderate expression of PKC alpha and beta was observed, while other PKCs (types gamma, epsilon, xi, and eta) were not detected. In vivo expression of PKC delta was demonstrated in the skin by in situ hybridization. In mast cell lines, the expression pattern of PKC isozymes was similar to that of +/+ CMC, except that the expression of PKC eta was detected in the IC2 cell line. The expression levels of PKC delta in CMC derived from c-kit-deficient mutants, W/W, Wv/Wv, and mi/mi, were lower than that of +/+ mice. These results indicate that PKC delta is the main isozyme in various types of murine mast cells and also suggest that the reduced level of PKC delta expression in mutant mice may be caused by a deficit in the signal transduction system through c-kit receptor.

Animals↗

PubMed1994

Distribution of intraepithelial nerve fibers in the feline glottis.

It is well known that the protective laryngeal closure is elicited by mechanical or chemical stimulation of the epithelium in the glottis. In this study we used light microscopic observation and relative examination of the intraepithelial nerve fibers in the glottis to clarify the perceptive mechanism using immunohistochemical methods. In the anterior glottis, a moderate number of protein gene product 9.5-immunoreactive intraepithelial nerve fibers were observed, most of which were found to be located just anterior to the vocal process. The number of fibers in the upper surface of the vocal fold was larger than that in the free edge and the lower surface. Only a few calcitonin gene-related polypeptide-immunoreactive fibers were seen, and substance P-immunoreactive fibers were rarely seen. On the other hand, a dense distribution of protein gene product 9.5-immunoreactive nerve fibers was observed throughout the epithelium of the posterior glottis. The number of calcitonin gene-related peptide-immunoreactive fibers was about 20% that of protein gene product 9.5-immunoreactive fibers, whereas the number of substance P-immunoreactive fibers was only 1% to 2%. The results of this study suggest that possible existence of regional differences in the perceptive mechanism between the anterior and posterior glottis.

Animals↗

PubMed1994

Isolation and characterization of a dipeptidyl aminopeptidase from Streptomyces sp. WM-23.

A screening test was undertaken to isolate microorganisms that produced dipeptidyl aminopeptidase. The hydrolytic activity toward alanyl-phenylalanine p-nitroanilide was found in a culture filtrate of a actinomyces strain (WM-23), newly isolated from a soil sample. The enzyme (WM-23 dipeptidyl aminopeptidase) was isolated from the culture filtrate as a homogeneous preparation. The WM-23 enzyme, inhibited by phenylmethylsulfonyl fluoride, may be classified to mammalian dipeptidyl aminopeptidase II. The enzymatic characteristics were investigated.

Amino Acid Sequence↗

PubMed1993

Purification and characterization of kumamolysin, a novel thermostable pepstatin-insensitive carboxyl proteinase from Bacillus novosp. MN-32.

We have found a novel type of thermostable, pepstatin-insensitive carboxyl proteinase in the culture filtrate of Bacillus novosp. MN-32. The carboxyl proteinase, which was named kumamolysin, was purified about 8,300-fold by column chromatography including DEAE-Sepharose CL-6B, Sephadex G-100, and TSKgel DEAE-5PW. The purified kumamolysin gave a single band corresponding to 41 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The molecular mass of kumamolysin was estimated to be 40 kDa by gel filtration. The isoelectric point of kumamolysin was estimated to be pH 3.5 by isoelectric focusing. Kumamolysin has maximum proteolytic activity at 70 degrees C and at pH 3.0. Kumamolysin specifically hydrolyzed the Leu15-Tyr16 peptide bond in oxidized insulin B-chain (Km = 9.0 x 10(-5) M, Kcat = 71 s-1; at pH 3.0, 30 degrees C), and additional cleavage at Phe25-Tyr26 was detected at a considerably lower rate. Kumamolysin is insensitive to the known carboxyl proteinase inhibitors pepstatin, diazoacetyl-DL-norleucine methyl ester, and 1,2-epoxy-3-(p-nitrophenoxy)propane. Kumamolysin has no similarity to the thermostable acid protease thermopsin from Sulfolobus acidocaldarius (Lin, X.-L., and Tang, J. (1990) J. Biol. Chem. 265, 1490-1495). Thus, the substrate specificity, the inhibitor sensitivity, the molecular mass, and the thermostability all suggest that kumamolysin is a novel type of carboxyl proteinase.

Amino Acid Sequence↗

PubMed1993

A three-dimensional reconstructive study of the layer structure of the human vocal cord.

The purpose of this investigation was to clarify the detailed histological structure of the human larynx and to clarify the cause of adaptation in high-frequency vibrations using three-dimensional histological reconstructions of human true vocal cords. In a first series of studies, 54 intact adult larynges were obtained from 398 human cavaders with known histories. Four of these laryngeal specimens were fixed in 10% formalin. Three of these were decalcified and embedded in paraffin and the other in Technovit-7100. The layer structure of each larynx was investigated with a three-dimensional reconstruction method using a personal computer. Results demonstrated that the elastic fiber layer in the superior surface of the vocal cord was wider than that in the inferior surface. The collagen fiber layer extends from the anterior commissure in a posterior direction. The elastic fiber layer connected both the anterior and the posterior macula flava, while the collagen fiber layer connected the thyroid cartilage and the anterior macula flava.

Aged↗

PubMed1993

A trial of individual dose intensity and relative performance factors in tegafur maintenance chemotherapy for head and neck cancer.

Tegafur (Sunfural-S), as masked compound of a 5-fluorouracil derivative, was administered orally as a maintenance chemotherapeutic agent at a dose of 600 mg/day in 98 cases of head and neck epithelial cancer. The effectiveness of the drug was evaluated by a statistical method involving two formulae: individual dose intensity (IDI) and relative performance (RP). When comparing patients rated above a reference IDI value of 1.0 with those rated below 1.0, it was not possible to predict patient survival or tumor-free rates. In contrast, the value of the RP did show such a correlation. These findings support the effectiveness of Tegafur as a maintenance chemotherapeutic treatment for head and neck cancer patients.

Aged↗

PubMed1993

Development and evaluation of a novel sterilizer with rotary vibrators.

A novel steam-air sterilizer with rotary vibrators was developed with the aim of promoting heat transfer and the effective sterilization of foods. To evaluate the effects of the sterilizer, experiments to examine heat transfer and sterilization tests were carried out. In the experiments to examine heat transfer, heat penetration factors of sterilizer with vibration, j and fh values, were 1.70 and 1.50, respectively, while those of sterilizer without vibration were 1.83 and 2.32, respectively. In the sterilization with vibration, no surviving cells were detected after 3 min, whereas 7 min were required for sterilization without vibration. The rate of the amino carbonyl reaction was repressed by heat treatment with vibration.

Amines↗

PubMed1993

Origin of laryngeal sensory-evoked potentials (LSEPs) in the cat.

Sensory-evoked potentials elicited by electrical stimulation of the superior laryngeal nerve were recorded at the dural surface on the cortex and the caudal medulla in anesthetized cats as a reflection of activities in the central afferent systems. These evoked potentials were named laryngeal sensory evoked potentials (LSEPs). LSEP was mainly composed of five components, N1, N2, N4, N12, and large biphasic potential (LBP). The peak latencies of these components were as follows: N1, 1.09 +/- 0.18 ms; N2, 1.93 +/- 0.19 ms; N4, 3.97 +/- 0.19 ms; and N12, 12.48 +/- 1.01 ms. LBP was a large component lasting from approximately 6 ms to 18 ms. The generator sources of these components were identified as follows: N1, nodose ganglion; N2, presynaptic potentials of the nucleus tractus of solitarius (NTS); N4, NTS complex including the postsynaptic potentials; and N12, activities of the frontal part of the orbital gyrus. The LBP was speculated to be generated from certain subcortical structures, such as the amygdala, the thalamus, the hypothalamus, and the basal ganglia.

Animals↗

PubMed1993

Detection of largyneal sensory-evoked potentials (LSEPs) in the cat.

We previously reported on evoked potentials elicited by electrical stimulation of the superior laryngeal nerve at an appropriate site on the dural surface as a reflection of activities in the brain stem and cortex in anesthetized cats. This evoked potential was called the laryngeal sensory evoked potential (LSEP). In this study we attempted to establish a less invasive procedure for measuring LSEP. The procedures were recording on the scalp using chloride-coated silver disk electrodes and stimulation by insertion of a bipolar platinum hooked wire electrode into the laryngeal mucosa. Evoked potentials could be detected using these less invasive procedures. The response morphologies and relative timing of LSEP components were quite similar for each method in a given cat. However, the amplitudes were slightly lower and the latencies were slightly prolonged with the less invasive techniques. These results suggest that this LSEP method might be applicable to human beings as a noninvasive method for evaluating the function of the laryngeal sensory pathway.

Animals↗

PubMed1993

Immunoelectron microscopic studies of synaptic organization in the intralaryngeal ganglia of the cat.

The synaptic organization of nerve terminals containing calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP), substance P (SP) and enkephalin (ENK) in the intralaryngeal local ganglia of the cat was investigated by immunoelectron microscopy. CGRP-immunoreactive (IR) and VIP-IR varicose fibers formed mainly axo-dendritic synapses, whereas SP-IR and ENK-IR varicose fibers made axo-somatic synapses to the principal neurons of the local ganglion. The synaptic specializations of the CGRP-IR varicosities were asymmetrical, or Gray's type I, whereas the other peptide-IR varicosities showed symmetrical, or Gray's type II, synaptic specializations. After denervation of the extrinsic nerves, CGRP-IR varicose fibers disappeared from the ganglion, but VIP-IR, SP-IR and ENK-IR varicose fibers and synapses remained. These results suggest that local ganglia act as an integration center of laryngeal function rather than as a unidirectional parasympathetic relay center.

Animals↗

PubMed1993

Enzymatic dimerization of penicillin X.

Penicillin X methyl ester was transformed into three types of dimer by laccase from Coriolus versicolor. The dimers are considered to be formed by free-radical addition of phenoxy radicals produced by laccase. The enzyme reaction with the ester as substrate was more suitable for forming dimers than that with the sodium salt as substrate. Penicillin X pivaloyloxymethyl ester was also transformed into a dimer, which had antibacterial activity in the presence of esterase.

Anti-Bacterial Agents↗