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Y Kikuchi

Publications and source records attributed to Y Kikuchi.

At least 577 records · Page 32Linked to original sources
PubMed1991

Coherence function between sympathetic neurogram and arterial pulse wave in animal with total artificial heart.

To assess the influence of the total artificial heart replacement on autonomic nervous system, sympathetic neurogram was analyzed by power spectrum and coherence function. Two pneumatically driven sac-type ventricular assist devices were implanted as biventricular bypass (BVB) in adult mongrel dogs. After the BVB pumping, natural heart was electrically fibrillated to constitute the BVB type TAH model. Renal sympathetic nerve activity (RSNA) was recorded using the bipolar electrode attached to the left renal sympathetic nerve. RSNA was amplified and integrated by the use of R-C integrator. Power spectra of the RSNA and the values of squared coherence between the arterial pressure waveform and the RSNA were calculated by the computer system. In animal with TAH, coherence at the cardiac rhythm frequency was decreased, and coherence at the TAH pumping rhythm frequency was increased. These results indicate that the arterial pulse wave which was observed in TAH animal contributed to sympathetic neurogram.

Animals↗
PubMed1991

[A case of a foreign body in the urinary bladder--a surgical suture needle was found in urinary bladder].

We report a case of an unusual foreign body in the urinary bladder. A 66-year-old male had undergone an operation of rectal cancer 6 years previously. He visited our hospital with irritative urinary symptoms. Urinalysis showed hematopyuria, and X-ray examination revealed a curved fine shadow (about 2 cm in length and 3 mm in width) at the vesical region. In cystoscopic examination, a calcified surgical suture needle was identified on the trigonal region. The needle was removed transurethrally by a stone crushing forceps. Thus, it was assumed that the needle had been left in the abdominal cavity at the operation 6 years ago and it had migrated into the bladder during these 6 years. Many cases of foreign bodies in the urinary bladder have been reported. However, to our knowledge, this is the first report of a surgical suture needle, in the bladder.

Aged↗
PubMed1991

[Restrictive lung disease].

It was found that functional residual capacity (FRC) invariably decreased during inspiratory elastic loaded breathing and that its magnitude increased progressively with an increase in the intensity of the load. This response could not be explained by chemoreflexes nor neural reflexes. Because the sensation of dyspnea decreased at lowered FRC (FRC-0.5 liter) than that at FRC during elastic loading, we speculate that FRC decreased behaviorally during elastic loading to reduce the sensation of dyspnea. We found that the respiratory muscle became fatigued more easily at FRC than at lowered FRC during elastic loading. We therefore conclude that the decrease in FRC may be one of the compensatory mechanisms during elastic loaded breathing.

Functional Residual Capacity↗
PubMed1990

Homeodomain binding sites in the 5' flanking region of the Bombyx mori silk fibroin light-chain gene.

Multiple A + T-rich stretches in the 5' flanking region of the Bombyx mori fibroin light-chain gene have been shown to bind two Drosophila homeodomain proteins, EVE (even-skipped) and ZEN (zerknüllt), with high affinities. Some of these sites fall into a class that has the established consensus sequence of the binding sites (TCAATTAAAT) for a diverse group of Drosophila homeodomain proteins, while others are quite heterogenous except that they all possess a core TAAT motif. Since clusters of homeodomain binding sites can also be found in the promoters of other silk protein genes, the fibroin gene and the sericin-1 gene, these observations suggest a possible involvement of some homeobox genes in the regulation of a group of silk protein genes.

Amino Acid Sequence↗
PubMed1990

Role of carbohydrate moiety of IL-5. Effect of tunicamycin on the glycosylation of IL-5 and the biologic activity of deglycosylated IL-5.

IL-5 is a T cell-derived lymphokine that induces B cell growth and differentiation in murine systems. In this study, we examined the role of carbohydrate moiety of IL-5 in the expression of biological function. IL-5 polypeptides translated in Xenopus oocytes were heterogeneous in terms of isoelectric point (pI 4.7 to 8.0) and m.w. (45,000 to 60,000 under nonreducing conditions) and yielded m.w. of 25,000 to 30,000 under reducing conditions. Treatment of rIL-5 with N-glycanase under reducing conditions yielded an IL-5 monomer of m.w. 12,000 to 14,000. Furthermore, deglycosylated rIL-5 that had been translated in the presence of tunicamycin showed very limited heterogeneity by two-dimensional gel electrophoresis (first dimension, nonequilibrium pH gradient electrophoresis; second dimension, SDS-PAGE). The m.w. was 27,000 to 28,000 under non-reducing conditions and migrated to m.w. 13,000 to 14,000 under reducing conditions. These results indicate that IL-5 is a glycoprotein carrying the N-glycosidically-linked carbohydrates. Treatment of IL-5 with sialidase caused the decrease in the heterogeneity in isoelectric point of IL-5. Deglycosylated rIL-5 that had been obtained from tunicamycin-treated oocytes could bind to IL-5-responding cells (T88-M), which express both high- and low-affinity IL-5 receptors, as efficient as intact rIL-5 under high-affinity conditions. Scatchard plot analysis of equilibrium binding of 35S-labeled rIL-5 to T88-M cells revealed that the dissociation constants (Kd) of glycosylated rIL-5 and deglycosylated rIL-5 were 127 pM and 110 pM, respectively. IL-5 activities determined by both B cell growth and differentiation assays were not affected by deglycosylation. These results indicate that N-linked glycoside moiety of IL-5 molecules may not play an essential role in the expression of its activity.

Animals↗
PubMed1990

Characterization of the interleukin 5-reactive splenic B cell population.

The characteristics of the interleukin (IL) 5-reactive splenic B cell population of C57BL/6 nu/nu mice, with respect to IL 5/IL2 reactivity, cell surface phenotype, VH gene family usage, autoreactivity and the structure of the IL5 receptor (IL5R), were analyzed. It was found that 2%-4% of splenic B cells express relatively high levels of IL 5R as determined by the binding of the anti-IL 5R monoclonal antibody R52.120. Over 90% of the splenic B cells that mature to IgM secretion upon activation with IL5 are comprised in this small subpopulation of B cells. Moreover, the vast majority of splenic B cells that mature to IgM-secreting cells when activated by IL2 also reside in this IL5R+B cell population. The cell surface phenotype of the IL5R+ splenic B cells is IgM+, B220+, Ly-1- and IL2R p55-. Upon activation with IL5 this cell surface phenotype changes, in that a vast majority of the B cells then express the p55 chain of the IL2R, whereas the level of IL5R decreases. VH gene family usage in the IL5-activated splenic B cells was analyzed by in situ hybridization. VH gene family usage was found to be random and not different from the VH genes expressed in LPS-activated B cells. Hybridoma collections from IL5-activated splenic B cells and LPS-activated B cells were screened and compared for the production of autoantibodies and antibodies directed against the haptens (4-hydroxy-3-iodo-5-nitrophenyl)acetyl (NIP) and 2,4,6-trinitrophenyl (TNP). In both collections high, but not significantly different frequencies of autoantibody-(32% IL5, 31.4% LPS) and of anti-hapten antibody (27.8% IL5, 18.6% LPS)-producing hybridomas were found. The structure of the IL5R on IL5-activated B cells was analyzed by 125I-labeled IL5 binding and cross-linking. About 100 high-affinity (10(-11) M) and 1000 low-affinity (10(-9) M) IL5-binding sites are present on IL5-activated splenic B cells, and both high- and low-affinity IL5R are similar to those expressed on the IL5-dependent B13 cell line. Cross-linking of 125I-labeled IL5 to the receptors on IL5-activated B cells revealed one major IL5-binding protein of 45-50 kDa molecular mass and another minor binding protein of 130-140 kDa. The same IL5-binding proteins are present on the IL5-dependent B13 cell line.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1990

Changes of lymphocyte subsets in peripheral blood before and after operation of patients with advanced ovarian carcinoma.

Comparison was made between lymphocyte subsets in peripheral blood from patients with benign ovarian tumor and those with advanced ovarian carcinoma. In addition, changes of lymphocyte subsets of patients with ovarian carcinoma before and after operation were also examined. The percentage and absolute number of CD3-/HLA-DR+ (B cells) in peripheral blood from patients with advanced ovarian carcinoma were significantly lower than values from patients with benign ovarian tumor, whereas both percentage and absolute number of CD3-/HLA-DR- (null cells) cells in patients with advanced ovarian carcinoma were significantly higher. Although there was no significant difference in natural killer (NK) cell subsets (CD57+ CD16- and CD57+ CD16+ cells) between patients with benign ovarian tumor and ovarian carcinoma, the percentage and absolute number of CD57-/CD16+ (highly differentiated NK cells) cells in patients with ovarian carcinoma were significantly higher than those in patients with benign ovarian tumor. Both the absolute number and percentage of CD3+/HLA-DR+ (activated T cells) cells in ovarian cancer patients with minimal residual tumors after operation were significantly increased, compared to the levels before operation, while the values in the patients with large residual tumors were significantly decreased. In addition, the percentage and absolute number of CD3-/HLA-DR- (null cells) cells in the patients with minimal residual tumors were significantly decreased after operation, while values in the patients with large residual tumors remained unchanged before and after operation. The patients with minimal residual tumors after operation were characterized by a significant increase in the percentage of CD57- CD16+ (highly differentiated NK cells) cells. On the other hand, in the patients with large residual tumors no change of the NK cell subsets was observed before and after operation.

Adult↗
PubMed1990

Effects of opioid peptides on the cellular immunity in spleen cells from intact nude mice or nude mice bearing human ovarian carcinoma.

The present study was designed to explore the effects of opioid peptides on the lytic activity of spleen cells from intact nude mice or nude mice bearing human ovarian cancer cells (KF). When the spleen cells from intact nude mice were incubated with various concentrations of opioid peptides, the ability of the spleen cells to lyse the KF cells was significantly stimulated between 0.05 nM and 50 nM concentrations of all opioid peptides used in this study. The degree of stimulation was most marked at 5 nM opioid peptides and the most marked stimulatory effect was obtained by alpha-endorphin. On the other hand, the lytic activity of spleen cells from nude mice challenged with the KF cells was about two-fold higher than that of intact nude mice, suggesting that spleen cells from nude mice challenged with KF cells have KF-cell-specific cytotoxicity. Even if the spleen cells were incubated with any concentration of alpha-endorphin or [Met]enkephalin indicated, the lytic activity remained unchanged. In contrast, only beta-endorphin resulted in a significant increase of the lytic activity between 0.5 nM and 50 nM. These results suggest that opioid peptides play a crucial role in immune surveillance mechanisms.

Animals↗
PubMed1990

Magnetic resonance imaging of spinal cord injury without radiologic abnormality.

A 3-year-old girl with spinal cord injury without radiologic abnormality (SCIWORA) is reported. Magnetic resonance imaging (MRI) showed an abnormal intensity of the spinal cord at the level of C7 to Th1 in the acute stage and severe atrophic change in the chronic stage. This is the first report of SCIWORA with positive diagnostic imaging. The mechanism of SCIWORA is discussed based on the positive MRI findings.

Child, Preschool↗
PubMed1990

Restorative effects of calmodulin antagonists on reduced cisplatin uptake by cisplatin-resistant human ovarian cancer cells.

In the present study, we attempted to determine effects of calmodulin antagonists (W-7 and W-5) on cisplatin uptake by human ovarian cancer cells, using KF cells derived from serous cystadenocarcinoma of the ovary and cisplatin-resistant cells (KFr). The degree of cisplatin resistance of the KFr cells was about 3.7-fold higher than that of the parent KF cells, with regard to the concentration of cisplatin required for 50% inhibition of cell proliferation (IC50). When KF and KFr cells were incubated with 10 micrograms/ml cisplatin for 4 hr, cisplatin-content in the KF cells was significantly higher than that in the KFr cells. When KF cells were incubated in the presence of W-7 (but not W-5), cisplatin uptake significantly increased, compared to cells treated with cisplatin alone. On the other hand, when KFr cells were incubated in the presence of 5 micrograms/ml W-7 or W-5, cisplatin uptake was significantly higher than uptake by KFr cells treated with cisplatin alone, being comparable to that by KF cells treated with cisplatin alone. Such an increase in cisplatin uptake seemed to bring about adjuvant effects to cisplatin of KFr cell proliferation in vitro. The KF tumor grown in nude mice took up 24.8 ng/g dry wt of cisplatin 4 hr after intraperitoneal administration. When cisplatin was administered with calmodulin antagonists, cisplatin uptake by the KF and KFr tumors was significantly increased, compared to that after treatment with cisplatin alone. In particular, the cisplatin uptake by the KFr tumor was about 2.5-fold higher than that by the KFr tumor treated with cisplatin alone. These results suggest that coadministration of calmodulin antagonists and cisplatin may be of use in patients with refractory ovarian cancer.

Biological Transport↗
PubMed1990

Structural comparison of murine T-cell (B151K12)-derived T-cell-replacing factor (IL-5) with rIL-5: dimer formation is essential for the expression of biological activity.

T-cell-replacing factor (TRF)/IL-5 is a T-cell-derived glycoprotein which has pleiotropic activity on lymphoid and myeloid cells. IL-5 polypeptide translated into Xenopus oocytes are heterogeneous in molecular size (40,000 to 60,000 under nonreducing conditions) and yields a monomeric form (Mr of 25,000 to 30,000) under reducing conditions (J. Immun., 140, 1175-1181, 1988). We purified T-cell-derived TRF and rIL-5 using anti-TRF/IL-5 antibody-coupled affinity column from supernatants of a T-cell hybridoma B151K12 and supernatants of HeLa cells, respectively, which had been transfected with murine IL-5 cDNA, and determined their partial N-terminal amino acid sequence (27 residues for B151-TRF and 13 residues for rIL-5). A single amino acid sequence of each sample obtained beginning from methionine that was identical to that predicted from IL-5 cDNA. This finding supports the notion that secreted B151-TRF polypeptide consists of 113 amino acids. Purified B151-TRF supported eosinophilopoiesis of human bone marrow cells as effective as mouse rIL-5 and human rIL-5. B151-TRF competitively inhibited 35S-labeled rIL-5 binding to target cells to the same extent at rIL-5. Treatment of purified rIL-5 and B151-TRF with reducing reagents such as 2-ME, sodium borohydride or dithiothreitol produced a monomeric form of IL-5 which did not exert a biological activity. Reduction and alkylation of rIL-5 caused the loss of binding to its target cells. These results strongly suggest that B151-TRF exists as a homodimer and its primary structure and secondary structures are identical to those of rIL-5. Moreover, the formation of inter-molecular disulfide bond(s) linked by two pairs of cystein residues is essential for the expression of the biological activity of mouse IL-5.

Amino Acid Sequence↗
PubMed1990

Cleavage of tRNA within the mature tRNA sequence by the catalytic RNA of RNase P: implication for the formation of the primer tRNA fragment for reverse transcription in copia retrovirus-like particles.

The retrovirus-like particles of Drosophila are intermediates of retrotransposition of the transposable element copia. In these particles, a 39-nucleotide-long fragment from the 5' region of Drosophila initiator methionine tRNA (tRNA(iMet) is used as the primer for copia minus-strand reverse transcription. To function as primer for this reverse transcription, the Drosophila tRNA(iMet) must be cleaved in vivo at the site between nucleotides 39 and 40. When a synthetic Drosophila tRNA(iMet) precursor was incubated with M1RNA, the catalytic RNA of Escherichia coli RNase P, other cleavages within the mature tRNA sequence were detected in addition to the efficient removal of the 5' leader sequence of this tRNA precursor. One of these cleavage sites is between nucleotides 39 and 40 of Drosophila tRNA(iMet). Based on this result, we propose a model for formation of the primer tRNA fragment for reverse transcription in copia retrovirus-like particles.

Animals↗
PubMed1990

Characterization of the murine interleukin 5 receptor by using a monoclonal antibody.

Murine interleukin 5 (IL-5), a lymphokine produced by helper T cells, is involved in the regulation of growth and differentiation of B cells and other hematopoietic cells. The receptor for IL-5 has been identified as two cross-linked complexes on T88-M cells (a murine IL-5-dependent early B cell line). In this study the IL-5 receptor was directly characterized by utilizing an immobilized IL-5 column and a rat monoclonal antibody, designated H7, directed against the IL-5 receptor. H7 completely inhibited specific binding of 35S-labeled IL-5 to T88-M cells, and bound to IL-5-responsive cells, e.g. T88-M, BCL1-B20 (a chronic B-cell leukemia), and MOPC104E (a myeloma), whereas H7 did not bind to IL-5-non-responsive cells, e.g. X5563 (a myeloma), FDC-P1 (an IL-3-dependent line), and MTH (an IL-2-dependent CTLL). H7 could barely bind to T88-M cells in the presence of IL-5, and immunoprecipitated a major band with an Mr of approximately 60 kd from the extract of surface-radioiodinated T88-M cells. The precipitation of this 60 kd molecule was inhibited by the addition of IL-5. Analysis with immobilized IL-5 also revealed that a 60 kd molecule bound specifically to IL-5-coupled beads compared with control beads. Furthermore, no additional molecule with a higher Mr that was recognized by H7 appeared under non-reducing, compared with reducing, conditions. The 60 kd molecule recognized by H7 could be digested with N-glycanase to yield a protein band of approximately 55 kd.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Antigenic determinants on rat metallothionein: fine epitope mapping for a murine monoclonal antibody and rabbit polyclonal antisera.

In order to determine the epitope of metallothionein (MT) to a murine monoclonal antibody (MT 189-14-7) which had been produced by immunization with rat MT 2 (Kikuchi et al. (1988) Mol. Immunol. 25, 1033-1036), various lengths of synthetic oligopeptides were tested for their inhibitory activities in competitive radioimmunoassay (RIA). The amino-terminal acetylated pentapeptide, AcMDPNC, exhibited an inhibitory activity comparable to that of native MTs, whereas the acetylated tetrapeptide, AcMDPN, and the deacetylated heptapeptide, MDPNCSC, were much less inhibitory. The results suggest that the major part of the epitope structure of MT to the MT 189-14-7 monoclonal antibody is located within the amino-terminal acetylated pentapeptide, AcMDPNC. The specificities of polyclonal rabbit anti-MT antisera raised against the same immunogen were also determined by using various animal MTs and synthetic peptides as inhibitors in the RIA. Among three antisera tested, two reacted with several amino-terminal oligopeptides similarly to the MT 189-14-7 antibody. The major epitope structures to these polyclonal antibodies were shown to be located within the acetylated tetrapeptide, AcMDPN. Another antiserum contained at least two different populations of antibodies: one consisted of antibodies reactive with the amino-terminal synthetic peptides, while the other was not reactive with them. These results suggest that, in the rabbit also, the amino-terminal region common to various animal MTs can be an epitope to antibodies raised against rat MT, as shown in the mouse. Moreover, the results indicate that the synthetic amino-terminal peptides are useful for determination of the specificity of polyclonal rabbit anti-MT antibodies, which have been widely used for the quantification of MTs.

Amino Acid Sequence↗
PubMed1990

Circumspinal decompression for thoracic myelopathy due to combined ossification of the posterior longitudinal ligament and ligamentum flavum.

Ossification of the posterior longitudinal ligament (OPLL) combined with ossification of the ligamentum flavum (OLF) in the thoracic spine can result in serious myelopathy, leading to circumferential compression of the spinal cord in advanced stages of the disease. The authors performed circumspinal decompression (circumferential decompression of the spinal cord) on these patients. This operation consists of two steps: posterior and lateral decompression of the spinal cord by removal of the OLF (first step) and anterior removal of the OPLL for anterior decompression (second step), followed by interbody fusion. In the first step, two deep parallel gutters, covering the extent of the OPLL to be removed anteriorly, are drilled down from the rear into the vertebral body along both sides of the dura to easily and safely remove the OPLL anteriorly at the second step. In the second step, the surgical approach varies according to the affected level; costotransversectomy in the upper thoracic spine and standard thoracotomy in the middle or lower thoracic spine. According to the authors, circumspinal decompression is not an easy procedure, but from their results in 10 patients, they identify it as a radical and promising surgical procedure.

Adult↗
PubMed1990

Complementarity between the 5'- and 3'-terminal sequences of rice stripe virus RNAs.

The 5' and 3' termini of four ssRNA species of rice stripe virus (RSV) isolate T were sequenced. The 3' termini of the three smallest ssRNAs, i.e. RNAs 2, 3 and 4, had the sequence 5' GACUUUGUGU 3'; that of ssRNA 1 had the sequence 5' GACUAUGUGU 3'. The 5'-terminal sequences of all four ssRNAs were 5' ACACAAAGUCC 3'. The 5'- and 3'-terminal sequences of about 20 bases of each ssRNA were almost complementary to each other. It is possible that RSV RNAs form panhandle structures characteristic of the RNA of negative-strand viruses.

Adenosine Triphosphate↗
PubMed1990

Disturbance in daily sleep/wake patterns in patients with cognitive impairment and decreased daily activity.

The sleep/wake patterns of 121 chronically ill, mentally and physically handicapped patients were visually monitored hourly for 14 consecutive days. Four types of sleep/wake patterns were found. In order to investigate how cognitive and physical functions correlated with sleep disorders, patients were classified based on a scale of mental function and the grading of daily activity. The percent of total sleep hours and the sleep rating, showing disturbances in sleep/wake pattern, were evaluated. We found a high degree of individuality in sleep/wake patterns. Sleep disturbance was associated with daily activity as well as with cognitive impairment. This monitoring system provides medical personnel with valuable information for clinical management.

Activities of Daily Living↗