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Biomedical subjects

C Suzuki

Publications and source records attributed to C Suzuki.

At least 19 recordsLinked to original sources
PubMed1992

Pyrogenic action of endothelin in conscious rabbit.

Injection of 0.3 nmol/kg endothelin(ET)-1 into the ear vein of conscious rabbits induced a significant increase in body temperature. ETB receptor specific agonist, namely 4-Ala-ET-1, also caused an elevation of the body temperature in a dose-dependent manner by injection into the ear vein of rabbit. These results suggest that ET play important roles in regulation of body temperature through selective stimulation of ETB receptor.

Analysis of Variance↗
PubMed1992

Bronchoscopy for airway foreign bodies: consideration based on an extraordinarily large one.

An extraordinarily large foreign body was lodged in the trachea of a 14-year-old boy. It was a rectangular piece of lead measuring 35 x 12 x 5 mm and was removed by a lower rigid bronchoscope introduced through a tracheostoma. Based on experiences of this and 6 other cases of tracheobronchial foreign body treated by this method, we discuss what approach should be used to extract tracheobronchial foreign bodies. We believe that lower bronchoscopy is still useful in removing foreign bodies very large or located in the peripheral bronchus, although it is used much less often today than before.

Adolescent↗
PubMed1991

T cell-mediated inhibition of erythropoiesis in aplastic anaemia: the possible role of IFN-gamma and TNF-alpha.

The inhibitory activity of T cells on autologous erythroid colony-forming units (CFU-E) (T cell inhibitory activity) in patients with aplastic anaemia (AA) was investigated. In 11 (32.4%) out of 34 AA cases, T cell inhibition on autologous CFU-E growth was greater than that in normal individuals. In order to evaluate the mechanism of this inhibitory activity, T cell surface markers, interferon (IFN) production in peripheral blood mononuclear cell (PBMNC) liquid culture, and cytokine levels such as IFN and tumour necrosis factor-alpha (TNF-alpha) in CFU-E clot cocultured with T cells, were measured in a portion of the patients. In five patients investigated for IFN production in PBMNC liquid culture, all produced statistically more IFN activity than normal individuals under phytohaemagglutinin (PHA-P) stimulation (P less than 0.01) with no relation to T cell inhibitory activity. In only one patient whose T cells displayed increased CD8 and HLA-DR antigen (CD8+HLA-DR+) and inhibitory activity, a significant amount of IFN-gamma was observed in CFU-E clot cocultured with T cells, and the addition of anti-IFN-gamma antibody to the coculture resulted in recovered CFU-E colony growth. These results suggest that IFN-gamma production by T cells may explain, at least in part, the pathogenesis of haematopoietic defects in AA. In other patients however, T cell inhibitory activity neither correlated to the T cell subpopulations (CD4+/CD8+, CD8+HLA-DR+), IFN production in PBMNC liquid culture, nor to IFN and TNF-alpha levels in CFU-E clot culture. The roles played by cytokines other than IFN and TNF-alpha on haematopoietic precursor cells require further evaluation in a larger sample of patients with AA.

Adolescent↗
PubMed1991

Syntheses and biological activities of endothelin-1 analogs.

Endothelin-1 analogs replaced by various amino acids at position 21, namely [X21]-ET-1, were synthesized, and their agonistic vasoconstrictor activity on rat thoracic aortic strips and receptor binding activity on rat brain membrane fraction were examined to elucidate their structure-activity relationship. The vasoconstrictor activities of [Tyr21]- and [Phe21]-ET-1 were one order of magnitude smaller than that of ET-1, and those of [His21]-, [Gly21]-, [Ser21]-, [Ala21]- and [Lys21]-ET-1 were more than two orders of magnitude smaller than that of ET-1. On the other hand, the replacements by Ile, Glu, Gln and Pro resulted in distinguished losses of the vasoconstrictor activities. In addition, preincubation with these analogs did not blunt ET-1-induced vasoconstriction and showed no antagonistic activity. The binding inhibitory activities of these analogs against 125I-ET-1 were approximately conformable to the vasoconstrictor activities with only a slight exception. These findings demonstrate that the phenyl group at position 21 is important for both the vasoconstrictor activity and the receptor binding activity.

Animals↗
PubMed1991

A new latent arginine esteropeptidase from human submaxillary gland.

One of the arginine esteropeptidases in human submaxillary gland was purified from microsomal membranes. The enzyme is inactive in membranes and requires trypsin treatment for its full activation. The trypsin-activated enzyme was purified to homogeneity. Its molecular weight was determined to be 94,000 by SDS-polyacrylamide gel electrophoresis. Among various substrates examined, the obtained enzyme exhibited high specific activities toward Tos-Arg-OMe (esterolysis) and D-Ile-Pro-Arg-pNA (amidolysis). The enzyme was inhibited by some serine proteinase inhibitors, whereas inhibitors of other types of proteinases did not affect or only scarcely affected it. The enzyme appears to be distinct from other arginine esteropeptidases previously described.

Amides↗
PubMed1990

Interleukin 6 perfusion stimulates reconstitution of the immune and hematopoietic systems after 5-fluorouracil treatment.

Effects of interleukin 6 (IL-6) on the functional capacity of the immune and hematopoietic systems in 5-fluorouracil (5-FU)-treated mice were determined. IL-6 (5 x 10(4) units/mouse/day) was administered s.c. for 7 days by implantation of an osmotic pump, since it was demonstrated that a much higher increase in the primary response to sheep RBC was observed by administration of slowly released rather than daily s.c. injection of IL-6. IL-6 perfusion significantly augmented anti-sheep RBC antibody responses depressed by 5-FU (150 mg/kg) treatment. IL-6 also was shown to stimulate hematological recovery in mice treated with 5-FU. Namely, IL-6 perfusion accelerated the recovery of the number of hematopoietic stem cells, granulocyte-macrophage progenitors, and mature neutrophils in the spleen, although IL-6 did not stimulate the recovery of the neutrophil count in blood. Recovery of the platelet count in blood was stimulated by IL-6. Furthermore, it was found that the endogenous IL-6 level in serum increased after 5-FU treatment, which suggests that IL-6 may play some role in the recovery of the immune and hematopoietic systems. Finally, we examined the effect of IL-6 on the survival of mice treated with a higher dosage of 5-FU (300 mg/kg). IL-6 perfusion produced a distinct increase in survival rate at Day 30 (74% versus 28%). It is of note that the number of bacteria (identified as Escherichia coli) cultured from the spleen and the liver decreased in IL-6-perfused mice. This IL-6-induced effect was accompanied by enhancement of an oxidative burst response. Moreover, the anti-E. coli antibody titer in serum was higher in IL-6-perfused mice than in control mice. These results suggest the possible use of IL-6 for stimulating the reconstitution of the immune and hematopoietic systems after chemotherapy treatment.

Animals↗
PubMed1990

Purification and characterization of a kallikrein from human submaxillary glands.

A tissue kallikrein was purified over 1500-fold from the postmicrosomal supernatant of human submaxillary glands. The purified enzyme gave a single band, corresponding to an apparent molecular weight of 42,000 on SDS-polyacrylamide gel electrophoresis. This enzyme cross-reacted with the anti-human urinary kallikrein antiserum. The purified enzyme was characterized in comparison with the purest human urinary kallikrein preparation. Both enzymes hydrolyzed the synthetic substrate, Ac-Phe-Arg-OMe, most effectively. Aprotinin, TLCK, and PMSF suppressed the enzyme activities, while SBTI, LBTI, and alpha 1-antitrypsin had no effect at all. The purified enzyme generated kinin from the natural substrate, kininogen. It was concluded therefore that the purified enzyme is a typical tissue kallikrein.

Amino Acid Sequence↗
PubMed1990

Temporal bone pathology in intracochlear schwannoma with profound hearing loss.

Intracochlear schwannoma was found in the temporal bone of a 85-year-old man in whom audiometric study, 26 days before death, had shown total deafness in the left ear. The tumor occupied the entire lumen of the cochlea in the basal turn involved Rosenthal's canal, but it occupied only the scala tympani in the second turn. Intralabyrinthine schwannomas are difficult to diagnose by clinical examination. They were discovered accidentally during destructive labyrinthectomy for presumed Ménière's disease or discovered incidentally by postmortem temporal bone pathology. Although intralabyrinthine schwannomas are a rare occurrence and cannot usually be diagnosed without surgery or postmortem histopathology, it is important to suspect the possibility of their existence in differential diagnosis of atypical Ménière's disease or unilateral idiopathic progressive deafness. Long-term follow-up is obviously necessary to exclude the tumor.

Aged↗
PubMed1990

[Localization of inflammation of tympanic cavity in human temporal bone pathology].

When we treat patients of otitis media, it is important to know the pathogenesis of otitis media. Therefore histopathological change of epithelium and bone in each site of tympanic cavity was observed using human temporal bones. Histopathological change of epithelium was classified as: acute, subacute and chronic in eighteen sites of tympanic cavity. Histopathological change of bone was observed in thirteen sites of tympanic cavity. And the frequency of histopathological change of epithelium and bone in each site was compared. A review of 350 temporal bones collected from autopsy cases revealed 171 (49.1%) to have otitis media, and a review of 170 temporal bones of otitis media cases revealed 165 (97.1%) to have bone changes. Differences in frequency of histopathological change of epithelium and bone existed in each site. Histopathological change in inferior portion of mastoid cells, round window niche and tympanic sinus was more frequent than in the other sites. Change of epithelium: in acute inflammation, no differences in frequency of histopathological change existed; in subacute inflammation and chronic inflammation, differences in frequency of histopathological change existed in each site. Change of bone: most changes were bone formation and bone reconstruction, but there was no clear finding that bone formation narrowed tympanic cavity without mastoid cells. Osseous destruction was found in mastoidectomy cases and cholesteatoma cases. It is thought that the frequency of inflammation is related to structure of cavity, aeration, immunologic activity or structure of the epithelium, and that the pathogenesis of otitis media, especially in chronic otitis media, is different in each site of tympanic cavity. It is thought that because the subjects of this study were not operated cases but autopsy cases, slight bone change was very frequent, but severe bone change, was rare. And we examined the pathogenesis of tympanic cavity of each case of acute inflammation and chronic inflammation of pars tensa and cases where there were no findings of inflammation in the pars tensa. In most cases of acute inflammation of pars tensa, inflammation of tympanic cavity was acute; in chronic inflammation of pars tensa, chronic. It was interesting that, in cases of normal pars tensa, inflammation was frequently found in tympanic cavity. Therefore, it is important to pay attention to the possibility of inflammation in tympanic cavity, even if the tympanic membrane appears normal.

Adolescent↗
PubMed1990

[Angio-immunoblastic lymphadenopathy with fibrosis of bone marrow, lymph node, liver and spleen, and proliferation of epithelioid cells in lymph nodes].

We report a 47-year-old man diagnosed as angio-immunoblastic lymphadenopathy with dysproteinemia (AILD) with fibrosis of the bone marrow, lymph node, liver and spleen, and proliferation of epithelioid cells in lymph node. He was admitted to a hospital in May, 1980 because of general fatigue, cough, fever and systemic lymphadenopathy. The diagnosis of AILD was based on a biopsy of right cervical lymph node. His symptoms were improved but recurred with the addition of icterus and progressive pancytopenia with decrement of prednisolone. He was referred to our hospital in July, 1980 and his physical examination revealed generalized lymphadenopathy, icterus and hepatosplenomegaly. Hemogram showed pancytopenia, and needle biopsy of the bone marrow disclosed fibrosis. Sections from the lymph node showed AILD with proliferation of epithelioid cells. Administration of 60 mg/day of prednisolone improved the fever, lymphadenopathy and hepatosplenomegaly. However he died suddenly of acute respiratory failure on July 30. Autopsy showed fibrosis of bone marrow, lymph node, liver and spleen with infiltration of abnormal lymphocytes, and pulmonary aspergillosis.

Cell Division↗
PubMed1989

Continuous perfusion with interleukin 6 (IL-6) enhances production of hematopoietic stem cells (CFU-S).

The in vivo effect of human recombinant IL-6 on hematopoietic stem cells (colony forming units in spleen, CFU-S) was investigated. Normal mice perfused with IL-6 for 7 days showed an increase in the serum level of IL-6 in a dose-dependent manner. This increase was accompanied by a dramatic enhancement (approximately 8-fold) in the number of spleen CFU-S 7 days after starting perfusion, although heat-treated IL-6 did not exhibit any activities. Enhanced CFU-S number returned to normal at 13 days after cessation of perfusion. These results suggest that IL-6 could be valuable for treating various forms of hematopoietic depletion.

Animals↗
PubMed1989

In vitro expansion of the murine pluripotent hemopoietic stem cell population in response to interleukin 3 and interleukin 6. Application to bone marrow transplantation.

The synergistic action of interleukin 6 with interleukin 3 on the proliferation of a murine hemopoietic stem cell population in a short-term liquid culture system was examined by radioprotective assay. The numbers of colony-forming units in spleen (CFU-S), together with granulocyte/macrophage colony-forming units and viable nucleated cells, were found to increase markedly in culture in the presence of both IL-3 and IL-6, compared with the presence of IL-3 or IL-6 alone. The peak CFU-S value in response to the combination of IL-3 and IL-6 was obtained 6 days after culture initiation, exceeding 5-fold of the input value. Consistent with these data, marrow cells cultured with both IL-3 and IL-6 for 6 days were shown to have a much higher capability of rescuing lethally irradiated mice than did controls. The results may portend the potential clinical use of the combination of IL-3 and IL-6, in particular, in bone marrow transplantation.

Animals↗
PubMed1988

Human recombinant IL-6/B cell stimulatory factor 2 augments murine antigen-specific antibody responses in vitro and in vivo.

The effects of human rIL-6/B cell stimulatory factor 2 (hrIL-6/BSF-2) from Escherichia coli on murine Ag, SRBC-specific antibody responses were examined in vitro and in vivo. HrBSF-2 was effective in augmenting the primary and the anamnestic plaque-forming cells response to SRBC in vitro. The augmentation of the primary response was apparent when B cell-enriched spleen cells (B cells) were cultured with BSF-2 in the presence of IL-2. On the other hand, hrBSF-2 alone strongly enhanced the anamnestic response in a dose-dependent manner when spleen cells from SRBC-immunized mice were used. These effects of BSF-2 were abolished completely by anti-BSF-2 antibody, but not by normal rabbit Ig. Cell depletion experiments indicated that L3T4 (CD4)+ T cells, but not Lyt-2(CD8)+ T cells, and adherent cells (macrophages) have an important role in this BSF-2-induced augmentation of the response. In addition, kinetic studies showed that hrBSF-2 acts on B cells in the anamnestic response even when added relatively late in the culture. Finally, it was determined whether BSF-2 also could be active in modulating antibody responses in vivo. BSF-2 was shown to enhance the primary and secondary antibody responses in mice. The most apparent effect of BSF-2 was observed in the secondary response.

Adjuvants, Immunologic↗
PubMed1988

A B-cell line having chromosome 14 aberration at break band q11 derived from an adult T-cell leukemia patient.

A B-cell line having translocations of chromosome 14 at break band q11 (the assigned locus of the alpha-chain gene of the T-cell antigen receptor) and chromosome 3 at break band p25 (the assigned locus of the c-raf-1 oncogene) was established from peripheral blood leukocytes of an adult T-cell leukemia (ATL) patient. The same chromosome 14 aberration at break band q11 and chromosome 3 aberration at break band p25 were also found in fresh T-cell leukemia cells. The B-cell line is surface immunoglobulin (sIg)+, immunoglobulin gene rearrangement+, ATL-specific antigen (ATLA)+, HTLV-1 proviral genome+, Epstein-Barr virus (EBV)-associated nuclear antigen (EBNA)+ and the EBV DNA genome+. The fresh T-leukemic cells were T-cell receptor gene rearrangement+, the HTLV-1 proviral genome+ and EBV DNA genome.

B-Lymphocytes↗
PubMed1987

Transplacental passage of digoxin in the case of nonimmune hydrops fetalis.

Successful treatment of intrauterine fetal tachyarrhythmia was reported in several cases recently. It was also pointed out that placental transfer of digoxin is unsatisfactory under certain conditions. However, it has not been clearly shown in which cases fetal digoxin level does not reach the maternal level. We present a case of nonimmune hydrops fetalis due to congenital atrial flutter in which digoxin concentration in the sera of the mother and the neonate showed significant dissociation, and discuss perinatological matters about the digoxin treatment and the factor that obstructs the transplacental passage of digoxin. Conclusively, we recommend that maternal digoxin concentration should be raised to near toxic level if the resolution of fetal and placental hydrops is not attained in the initial digoxin loading.

Adult↗