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Biomedical subjects

T Masuda

Publications and source records attributed to T Masuda.

At least 703 records · Page 39Linked to original sources
PubMed1984

[Evaluation of cord functions in patients with cervical radiculomyelopathy using cortical and spinal somatosensory evoked potentials].

UNLABELLED: It is desirable for neurosurgeons to be able to evaluate cord functions. To assess electrophysiologically functional status of spinal cord, cortical and spinal somatosensory evoked potentials (SEP) were studied in 33 patients with cervical radiculomyelopathy; 11 cases of cervical spondylosis, 11 cases of OPLL, 3 cases of narrow canal, 2 cases of narrow canal with OPLL, 3 cases of intradural extramedullary tumor, 2 cases of intramedullary tumor and one case of traumatic cervical cord injury. Before the operation cortical SEP was recorded from post-Rolandic area by the median nerve stimulation. Spinal SEP was recorded from the dorsal surface of the cord after partial and complete laminectomy, or before and after tumor removal. RESULTS: Cortical SEP showed abnormalities in 45% of the cases, whose abnormalities were disappearance of the early components such as P1N1 wave, P1 to P2 complex or P1 to P3 complex and delay of the peak latency. Spinal SEP showed abnormalities in 42% of the cases, and the abnormal patterns were divided into 3 groups as follows: Type 1: Slightly abnormal, P1 and N1 waves are well recorded, whereas the P2 wave is absent or markedly suppressed in the amplitude. Type 2: Moderately abnormal, the P2 wave is flat and in addition the N1 wave is diminished in the amplitude. Type 3: Severely abnormal, only the P1 wave is recorded and the N1 to P2 complex is absent. Type 1 was obtained from 3 patients, type 2 from 9 patients, and type 3 from 2 patients. Cortical and spinal SEP were closely related to deep sensations, and cortical SEP was relatively correlated with superficial sensations. There were no differences of spinal SEP in most of the cases between partial and complete laminectomy. In intradural extramedullary tumor, however, good spinal SEP was recorded in collapsed cord after the tumor removal. Clinical symptoms were improved postoperatively in 80% of patients with both normal cortical and spinal SEP. It is concluded that cortical and spinal SEP are useful for prognostic value in patients with cervical radiculomyelopathy.

Cerebral Cortex↗
PubMed1983

Immunocytochemical demonstration of hydroxyindole O-methyltransferase (HIOMT), neuron-specific enolase (NSE) and S-100 protein in the bovine pineal gland.

The immunocytochemical localization for hydroxyindole O-methyltransferase (HIOMT), neuron-specific enolase (NSE) and S-100 protein in the bovine pineal gland is described in this paper. Most of the pinealocytes showed immunoreactivities to a HIOMT antiserum and an NSE antiserum, simultaneously. Neither HIOMT-nor NSE-immunoreactivity was observed in a few pinealocytes. On the other hand, dispersed interstitial cells (glial cells) were stained only by an S-100 protein antiserum. No evident HIOMT-immunoreactivity was observed in the retina and intestinal mucosa, where HIOMT has been suggested to occur.

Acetylserotonin O-Methyltransferase↗
PubMed1983

Developmental changes in the translatable mRNA for beta subunit of S-100 protein in rat brain.

The presence of mRNA coding for beta subunit of S-100 protein was demonstrated in polyadenylated RNA from the rat brain in vitro translation in a reticulocyte lysate cell-free system. The products were identified with S-100 protein beta subunit using the immunoprecipitation of the reaction products with the specific antisera, comigration of the isolated, labelled peptide with the purified S-100 protein in SDS-polyacrylamide gel electrophoresis and fluorography and the same retention time of the labelled S-100 protein beta subunit with authentic S-100 beta subunit by high performance liquid chromatography. The size determination of mRNA for S-100 protein on sucrose density gradient centrifugation gave 6-8 S. The assay gave a linear response with increasing amounts of polyadenylated RNA, allowing quantitation of mRNA level for S-100 protein in polyadenylated RNA. During the prenatal period and 10 postnatal days, only minute amounts of mRNA for beta subunit of S-100 protein could be found, however a dramatic increase of mRNA for beta subunit of S-100 was observed within the period of 10 to about 30 days and the mRNA level maintained a plateau from 40 days to adult age. These date indicate that the development changes in the amount of S-100 protein in the rat brain found by other authors is strongly correlated with the changes in the level of its translatable mRNA.

Aging↗
PubMed1983

The distribution of myoneural junctions in the biceps brachii investigated by surface electromyography.

The location of the myoneural junction was investigated by a surface electromyogram. During a voluntary muscular contraction, an electrode array was placed on the skin overlying the muscle to detect myoelectric potentials propagating in both proximal and distal directions along the muscle fibers. The source of the propagating waves was presumed to mark the location of the myoneural junctions. The recordings were repeated to cover the whole muscle surface and the distribution of myoneural junctions was determined. Myoneural junctions in the biceps brachii were located nearly at the middle length of the muscle and were distributed in a zone across the muscle. The distribution showed differences in 3 subjects examined. In 1 subject, myoneural junctions occupied a single zone, while the other 2 subjects had 2 parallel zones separated by 10-20 mm. This information about the location of myoneural junctions is important for determining the electrode position in an electromyogram study.

Adult↗
PubMed1983

The propagation of motor unit action potential and the location of neuromuscular junction investigated by surface electrode arrays.

A myoelectric signal was recorded from the biceps brachii muscle using surface electrode arrays which consisted of 15 pieces of stainless steel wire placed parallel to each other with 5 mm interelectrode spacing. The electrode assembly was positioned parallel to the underlying muscle fibers and amplifiers were connected bipolarly to 11 pairs of adjacent electrodes. In the chart of recorded signals a propagation of the action potential was observed, originating from a neuromuscular junction and traveling both in the proximal and distal directions. In one recording under an isotonic and isometric contraction condition, two neuromuscular junctions were found to be active. One was located approximately at the center of the muscle and the other was 15 mm distal from it. It was found that the amplitude of the myoelectric potential originating from the distal neuromuscular junction increased gradually during a 1 min heavy muscular loading (50% maximum voluntary contraction).

Action Potentials↗
PubMed1983

Differentiation-associated changes of glycolipid composition and metabolism in mouse myeloid leukemia cells. Induction of globotriaosylceramide and a galactosyltransferase.

This study was to find out whether induction of special glycolipids or glycosyltransferases for glycolipid synthesis which might be involved in the cell functions occurred during the differentiation. Mouse myeloid leukemia cell line (M1-), the differentiated cells (M1+), and a subcloned cell line (Mm1) were used for this purpose. Gangliotriaosylceramide (GA2) was the major glycolipid component in M1- cells. As a result of differentiation of M1- into M1+ cells, globotriaosylceramide (CTH) was newly induced as the main glycolipid, while GA2 decreased to a minor component. GA2 was found to be the main glycolipid in Mm1 cells but no CTH was recognized. All precursor glycolipids and glycosyltransferases required to complete the biosynthetic pathway glucosylceramide (CMH) leads to lactosylceramide (CDH) leads to GA2 leads to gangliotetraosylceramide (GA1) leads to sialosylgangliotetraosylceramide (GM1b) were found in M1- and also in Mm1 cells. A galactosyltransferase activity for CTH synthesis from CDH increased 10 fold during the differentiation. The induction of CTH in M1+ cells could be attributed to the increase of the galactosyltransferase activity. Both CTH as a surface marker and the galactosyltransferase as an enzyme marker are proposed as valuable markers of differentiation in M1- cells. Besides the galactosyltransferase, N-acetylglucosaminyltransferease involved in the formation of lactotriaosylceramide (amino-CTH) increased up to 3 fold during the differentiation. The increase of the enzyme activity seemed to be responsible for the biosynthesis of lactoneotetraosylceramide (paragloboside) which appeared in M1+ cells.

Animals↗
PubMed1983

T-cell hybridoma co-expressing Fc receptors for different isotypes. I. Reciprocal regulation of Fc alpha R and Fc gamma R expression by IgA and interferon.

To clarify the co-expression phenomenon of T-cell Fc receptors (FcR) specific for different isotypes on the clonal level, a murine hybridoma clone T2D4 was studied. T2D4 cells originally reported to bear FcR for IgG (Fc gamma R) and to release a Fc gamma R-related T-cell factor binding to IgG (immunoglobulin binding factor; IBF) proved to have also the receptor for IgA. The binding of IgA was detected by rosette formation with trinitrophenylated ox red blood cells (TNP-ORBC) after preincubation of T2D4 cells with MOPC 315 IgA having anti-TNP activity, or directly with TNP-ORBC sensitized with MOPC 315 IgA. While the binding of MOPC 315 IgA was competed for by IgA but not by IgG2A nor IgG2B, IgA failed to inhibit the rosette formation of the cells with ORBC sensitized with rabbit IgG antibody (EA ox gamma), proving that T2D4 cells express FcR specific for IgA (Fc alpha R) in addition to Fc gamma R. Co-expression of both receptors on the same cell surface was demonstrated by a double rosette technique using TNP-quail red blood cells (TNP-QRBC) and EAox gamma. Fc alpha R activity of the cells was completely abrogated by 15 min. incubation with 0.1 mg/ml trypsin, whereas Fc gamma R was resistant even to 1 mg/ml trypsin. The expression of Fc alpha R was augmented (up-regulation) by IgA at the concentration above 300 micrograms/ml and inhibited (down-regulation) by 1000 u./ml of murine beta-interferon (beta-IFN). Conversely, the expression of Fc gamma R was down-regulated by IgA and up-regulated by alpha-IFN. Thus, Fc gamma R and Fc alpha R are co-expressed and reciprocally regulated on these cell lines. The possible co-production of IBF and the Fc alpha R-related binding factor specific for IgA is discussed.

Animals↗
PubMed1983

T cell hybridomas coexpressing Fc receptors (FcR) for different isotypes. II. IgA-induced formation of suppressive IgA binding factor(s) by a murine T hybridoma bearing Fc gamma R and Fc alpha R.

T2D4 murine T hybridoma cells have previously been shown to express Fc receptors (FcR) for IgG (Fc gamma R) and for IgA (Fc alpha R) and to produce an IgG binding factor (IgGBF) that suppresses IgG and IgM responses. In the present work we report on the behavior of IgA bound to T2D4 cells and on the production of IgA binding factor (IgABF) and its ability to suppress IgA antibody production. A dose-dependent binding of MOPC315 IgA with anti-TNP activity by T2D4 cells was demonstrated by rosette formation with trinitrophenylated ox red blood cells (TNP-ORBC) and fixation of iodinated DNP-BSA. IgA bound to the cells disappeared after a short-term culture of 3 hr at 37 degrees C, but not at 4 degrees C. Because this phenomenon was inhibited by 0.1% sodium azide and 100 microM dansylcadaverine, a transglutaminase inhibitor, Fc alpha R-IgA complexes seemed to be released by an active process involving receptor movement. In the culture supernatant of IgA-treated T2D4 cells, we detected a factor(s) that binds to IgA-Sepharose and competitively inhibits the binding of IgA to T2D4 cells. The factor (IgABF) failed to inhibit the rosette formation of Fc gamma R(+) cells with IgG-sensitized ORBC (EAox gamma), indicating that it binds specifically to IgA. IgABF was undetectable in the culture supernatants of untreated T2D4 cells of Fc alpha R(-) BW5147 T lymphoma cells used as parent cells for the establishment of the hybridoma. To study the effect of IgABF on antibody formation, culture filtrates of IgA-treated or untreated T2D4 cells were fractionated on IgA-Sepharose beads and were added to BALB/c spleen cells cultured with pokeweed mitogen. By use of a reverse plaque assay, it was shown that the IgA plaque-forming cell (PFC) response was suppressed by the acid eluate but not by the effluent of IgA-Sepharose beads incubated with the filtrates of IgA-treated T2D4 cell cultures. The suppression was IgA specific, because neither IgG nor IgM responses were suppressed by the eluate. As expected, there was no significant IgA suppressive activity in the acid eluates of the beads incubated with the culture filtrate of untreated T2D4 cells or IgA-treated BW5147 cells. IgA-specific suppressive activity proved to be due to IgA binding factor(s), because suppressive activity in the eluate was completely adsorbed by IgA-Sepharose but not by IgG- nor BSA-Sepharose.

Animals↗