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T Shibuya

Publications and source records attributed to T Shibuya.

At least 145 records · Page 8Linked to original sources
PubMed1995

[PUVA therapy for cutaneous acute graft-versus-host disease--a case report].

We performed 8-methoxypsolaren and ultraviolet A (PUVA) therapy as a second line treatment for stage +3 cutaneous acute graft-versus-host disease (GVHD) in a 10-year-old girl who had undergone unrelated bone marrow transplantation. Although prednisolone as first line therapy was not effective, the cutaneous lesion began to improve after several times of PUVA treatment and completely disappeared following 11 times of irradiation without additive systemic immunosuppressive therapy. PUVA therapy was considered as a useful treatment for cutaneous acute GVHD.

Acute Disease↗
PubMed1994

Suppression by antithrombotic agents of pseudointimal hyperplasia of polytetrafluoroethylene graft implanted into venous system.

The lumen of the polytetrafluoroethylene graft (PTFE) implanted into a rabbit inferior vena cava (IVC) was markedly narrowed by 4 weeks after grafting. This was due to initial thrombosis on the luminal surface of the graft, which was followed by pseudointimal hyperplasia (PIH). To elucidate the role of the initial thrombosis in subsequent PIH, the effect of ticlopidine (T) and/or warfarin (W) on PIH was studied in an animal model. A PTFE tube graft was implanted into a rabbit IVC. Twenty eight rabbits were randomly assigned to the following experimental groups. Eight rabbits without antithrombotic agents were observed for 2 weeks (A, n = 4) and 4 weeks (B, n = 4) after grafting. T (100 mg/kg/day) and W (0.33 mg/kg/day) were orally administered for 4 weeks to group C (n = 4) and group D (n = 4), respectively. A combination of a half dose of T and W ((T + W)/2) was given for 2 weeks (E, n = 4) and 4 weeks (F, n = 4) after grafting. Four rabbits in group G received the combination of T and W for the first 2 weeks and were observed for an additional 2 weeks without medication. All the grafts were patent at time of harvest. The dry weight of the intraluminal deposit (DW) was determined as an indicator of PIH (A:35 +/- 1 mg/graft, B:40 +/- 8, C:22 +/- 3, D:22 +/- 3, E:14 +/- 2, F:15 +/- 3, G:23 +/- 2). Administration of T or W was equally effective in reducing DW and (T+W)/2 was more effective than a single agent.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Production of parathyroid hormone-related protein by cultured human myeloma cells.

We examined whether or not parathyroid hormone-related protein (PTH-rP) is produced in cultured human myeloma cells. PTH-rP protein was detected in the cell extract of one (U266) of 6 myeloma cell lines examined by radioimmunoassay. Also we demonstrated the expression of PTH-rP mRNA in all of the 6 lines. These findings indicate that PTH-rP may be one of the factors responsible for the bone destruction or hypercalcemia in multiple myeloma.

Base Sequence↗
PubMed1994

Gadolinium DTPA-enhanced magnetic resonance imaging of cerebral contusions.

The morphological characteristics of cerebral contusions in head trauma patients suggest that an increase in cerebrovascular permeability is responsible for the contusion edema which develops within 1-3 days posttrauma. In the present study, 10 patients with cerebral contusions (mean age, 38 years old; 8 males and 2 females) were examined by gadolinium (Gd)-DTPA enhanced magnetic resonance imaging (MRI) at 1-2 days after trauma. Gd-DTPA (0.3 mmol/kg) was infused intravenously over a period of 30 min. MRIs were taken before, and at 2 and 4 hours after initiation of the Gd-DTPA administration. It was found that contusion edema areas were frequently enhanced by Gd-DTPA at 2 hours. The enhancement diminished at 4 hours. These findings appear to be inconsistent with the results of previously reported similar studies in which enhancement was detected at 6-9 days posttrauma but not during the period earlier than 6 days. This discrepancy may be attributable to the presence of a high blood concentration of Gd-DTPA for a longer period of time and a delay in the time at which MRIs were taken in the present study. The present data indicate that an increased cerebrovascular permeability occurs at as early as 1-2 days posttrauma, and suggest that contusion edema which progresses during the initial 1-3 days may be at least partially vasogenic in nature.

Adolescent↗
PubMed1994

Congenital aortic regurgitation caused by a rudimentary noncoronary cusp: report of a case.

A 14-year-old asymptomatic boy was admitted to our department for investigation of a diastolic murmur which had been discovered by his family doctor during a routine examination. Echocardiography showed aortic regurgitation with dilatation of the left ventricle. Inspection of the aortic valve at the time of operation revealed normal left and right cusps with a rudimentary noncoronary cusp. An aortic commissuro-plication was performed and a new bicuspid aortic valve successfully reconstructed. His postoperative course was uneventful and he has been well and leading an active life since his discharge from hospital.

Adolescent↗
PubMed1994

Effect of opioid peptide antisera on nitrous oxide antinociception in rats.

This study was performed to examine the effects of ICV injection of antiserum against beta-endorphin (beta-EP) or methionine-enkephalin (ME) on nitrous oxide-induced antinociception in rats using the hot plate test. The injection of beta-EP antiserum reversed the antinociceptive effect of nitrous oxide in a dose-related manner up to 200 micrograms/rat. However, antagonism of nitrous oxide by 400 micrograms beta-EP antiserum was comparable to that produced by 200 micrograms. On the other hand, similar amounts of ME antiserum had little effect against nitrous oxide antinociception. These findings suggest that beta-EP may play an important role in the antinociceptive effect of nitrous oxide.

Analgesics↗
PubMed1994

Summary report of the Working Group on Mammalian Germ Cell Tests.

The two tests considered by the Working Group were the mammalian germ cell cytogenetic assay and the rodent dominant lethal test. It was agreed that both tests were mainly used for identification of germ cell hazards, however, that the commonly applied protocol of the dominant lethal assay often supplied information for hazard characterization such as sensitivity of particular developmental stages of male germ cells. No particular species or strains were indicated. Concurrent solvent controls were regarded as indispensable for both tests. In the discussion of the mammalian germ cell cytogenetic assay, harmonization was obtained to a large extent with the cytogenetic bone marrow assay regarding the number of animals (5), the number of cells analyzed per animal (200), the highest exposure dose (MTD) and sampling times (twice within 24 and 48 h after dosing). However, it was pointed out that only the single acute exposure was adequate for the mammalian germ cell cytogenetic assay. Furthermore, it was stated that only structural chromosome aberrations could be analyzed and that it was not informative to score polyploidies or aneuploidies. In the discussion of the rodent dominant lethal test, it was stated that the assay was generally performed with treated males, however, increasing concern about female specific effects required that a protocol for female dominant lethal testing should be developed and validated. Acute and subacute treatment schedules were considered equally acceptable. It was regarded as highly important that the entire male germ cell development from meiosis to mature sperm was covered in the test protocol either by the appropriate mating schedules after single dosing or by subchronic dosing during the respective period. Postimplantation loss, preimplantation loss and fertility rate were the main parameters to be assessed in the rodent dominant lethal tests. It was agreed that the size of the experiment depended on the spontaneous frequency of dead implants, the mating scheme and the statistical design of the experiment.

Aneuploidy↗
PubMed1994

Studies on mutations in male germ cells of transgenic mice following exposure to isopropyl methanesulfonate, ethylnitrosourea or X-ray.

Transgenic mice have recently been used for mutagenesis assays in vivo. The present study was undertaken to clarify whether such assays can detect mutations induced after treatment of male germ cells in mouse with isopropyl methanesulfonate (iPMS), ethylnitrosourea (ENU) or X-ray irradiation. The transgenic mice used for assay are Muta Mouse (MM) strain, which carries 80 copies of the bacterial lacZ gene per cell as targets for mutagenesis. Male MM animals were given a single intraperitoneal injection of 200 mg/kg iPMS, 150 mg/kg ENU or were irradiated with 500 rads of X-rays. Vasa deferential sperm, caudal epididymal sperm and/or whole testes were extracted at various times after treatment with each agent. After the genomic DNA was extracted from each tissue, mutation analysis at the lacZ locus was carried out by the method of Myhr et al. The spontaneous lacZ- mutant frequencies were on the order of 10(-5)-10(-6). The lacZ- mutant frequencies in all treatment groups were increased over the control animals. The iPMS-induced mutant frequency in postmeiotic stages was low. However, ENU induced relatively high mutant frequencies in the spermatogonia. X-rays induced mutant frequencies in the late spermatid and early spermatid stages that were higher than the mutant frequencies in spermatogonia. Mutant frequencies in MM detected after treatment of male germ cells with ENU or X-rays were lower than mutant frequencies detected by the mouse specific-locus test in previous reports. Hence, considering the lower resolution power of the transgenic animal mutagenesis assays using the target lacZ gene compared with the specific locus test, to detect mutations induced in male germ cells, it is not clear whether this assay is a practical alternative to the specific locus test.

Animals↗
PubMed1994

Subendothelial layer of pseudointima of polytetrafluoroethylene graft is formed by transformation of fibroblasts migrated from extravascular space.

A well organised pseudointima is formed in polytetrafluoroethylene (PTFE) grafts within 4 weeks after implantation into inferior vena cava (IVC) of rabbits. To investigate the process of the subendothelial organisation of pseudointima, an animal experiment was conducted. The outer wall of PTFE graft (30 microns fibril length, 3 mm inner diameter, 3 cm long) was coated with 10 um silicon film in the following ways to prevent cellular ingrowth from the extravascular space: non-coating; full-length coating; half-length coating; and full-length coating excluding 5 mm midportion. These grafts were implanted into rabbit IVC and were harvested 4 weeks later. All the grafts were patent but the lumen of the non-coated area was narrowed by pseudointimal hyperplasia. The degree of the hyperplasia estimated by dried tissue deposit was inversely proportional to the length of the coating. The coverage of the luminal surface with endothelial-like cells was noted at anastomotic areas and also at the surface corresponding to the non-coated area. Light microscopy and immunostaining studies on the non-coated midportion revealed the presence of fibroblasts in the interstices of PTFE and smooth muscle cells and myofibroblasts in the pseudointima. Transmission electron microscopy confirmed the presence of myofibroblasts in the midportion of the non-coated area. No transmural capillary ingrowth was observed in the midportion by histological and immunohistochemical analysis. These observations suggest that the subendothelial layer of pseudointima in PTFE grafts is formed by proliferation and transformation of fibroblasts migrating from the extravascular space and that endothelial-like cells may also be derived from such transformation.

Animals↗
PubMed1994

Cytomegalovirus (CMV) antigenaemia for rapid diagnosis and monitoring of CMV-associated disease after bone marrow transplantation.

A technique for the rapid detection of cytomegalovirus (CMV) antigen-positive blood leucocytes (CMV antigenaemia) was evaluated in 15 marrow transplant patients as a means of diagnosis and for monitoring CMV-associated disease. CMV antigenaemia was determined by direct immunoperoxidase staining of leucocytes with a peroxidase-labelled monoclonal antibody, HRP-C7, which binds an immediate-early antigen of human CMV. CMV antigenaemia occurred in 7/15 marrow transplant patients (47%) and was initially detected between 4 and 6 weeks after transplantation. CMV-associated diseases developed in 3/15 patients (20%). All patients with CMV-associated disease had a relatively large number of CMV antigen-positive leucocytes, exceeding 10 per 50,000 white blood cells (WBCs). In the remaining 12 patients, CMV antigen-positive leucocytes were less than 10 per 50,000 WBCs or were undetectable. CMV-associated disease did not develop in these patients during the period of monitoring. CMV antigen-positive leucocytes were detected more frequently in patients who developed acute graft-versus-host disease (GVHD) or haemorrhagic cystitis than in those without such complications. CMV antigens were detectable from 1 to 4 weeks before the onset of CMV-associated disease which allowed initiation of ganciclovir treatment at an early stage. The degree of CMV antigenaemia paralleled the clinical symptoms and signs, higher degrees of antigenaemia being associated with more significant disease. Thus, the detection of CMV antigen-positive blood leucocytes is useful for the diagnosis and monitoring of CMV-associated disease following bone marrow transplantation.

Acute Disease↗
PubMed1994

Involvement of interferon-gamma and macrophage colony-stimulating factor in pathogenesis of haemophagocytic lymphohistiocytosis in adults.

We investigated the role of monocyte/macrophage-activating cytokines in pathogenesis of haemophagocytic lymphohistiocytosis (HLH) in 21 adult patients. Sera from patients with active HLH contained extremely high levels of macrophage colony-stimulating factor (M-CSF) and of interferon-gamma (IFN-gamma). These levels returned to almost normal during remission. Neither interleukin-4 nor granulocyte/macrophage colony-stimulating factor could be detected. Active HLH sera also contained high concentrations of inflammatory monokines, such as interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha). Serum concentrations of soluble CD8 and soluble interleukin-2 receptor were extremely high during active HLH, and returned to virtually normal levels during remission. Circulating CD2+ T-cells obtained from patients with active HLH spontaneously secreted M-CSF and IFN-gamma in vitro, whereas circulating monocytes did not produce detectable levels of both M-CSF and IFN-gamma, but produced high levels of IL-6 and TNF-alpha. These findings suggest that IFN-gamma and M-CSF at least partly from T-cells, such as CD8+ T-cells, might contribute to activation of monocytes or histiocytes, resulting in the up-regulated monokine production and haemophagocytosis in HLH.

Adolescent↗
PubMed1994

[A case of mefloquine-resistant Plasmodium falciparum malaria with convulsion after antimalarial treatment].

We report a case of 40-year-old with chloroquine- and mefloquine-resistant Plasmodium falciparum. He had a single grand mal seizure 37 days following retreatment with quinine intravenously, which resulted in rapid clearance of fever and parasitemia, in addition to mefloquine. He had a long history of seizures, which were well controlled by phenytoin. Because he has never had such a seizure before and computerized tomographic scanning of the brain after admission showed no abnormal findings which caused convulsions, it seemed to be an adverse reaction caused by antimalarial drugs. It is possible that a double or triple combination treatment for the emergence of multiresistant falciparum malaria might more frequently produce severe side effects, such as psychiatric reactions and convulsions. This case suggests that physicians must have a long follow-up period for chronic toxicity of antimalarial drugs, especially after using drug combinations for falciparum malaria.

Adult↗
PubMed1994

Adsorption of salivary proteins to the surface of oral streptococcal cells.

Oral tissues, especially tooth surfaces, are covered with a layer of salivary proteins. Oral bacterial cells that adsorb to salivary components accumulated on the tooth surface are, as a rule, covered with the same components, especially proteins. Thus, it is possible that the salivary proteins covering the bacterial cells are related to the adhesion of bacteria to oral tissues. The aim of this study was to clarify the mechanisms of adsorption of salivary proteins to the surface of Streptococcus sanguis, S. mitis and S. salivarius using an adsorption assay with salivary proteins labeled with tritiated formaldehyde. The results showed that salivary proteins adsorbed more to S. salivarius than to S. mitis, and least to S. sanguis. It was evident that hydrophobic bonding was involved in the adsorption of salivary proteins to the bacterial cells tested. The amount of salivary proteins adsorbed to S. mitis and S. salivarius was decreased by the presence of phosphate, that to S. sanguis was increased by the presence of a divalent cation such as Ca2+, and that to all bacteria tested was inhibited in different ways by the presence of sugars. The amount of salivary proteins adsorbed to S. sanguis and S. salivarius was reduced effectively by pretreatment of the cells with trypsin, chymotrypsin and papain. In the case of S. mitis, the amount of adsorbed salivary proteins was decreased by pretreatment of the cells with chymotrypsin only, and was increased by pretreatment with lipase. These results indicate that there are different mechanisms of adsorption of salivary protein to the cell surfaces of oral streptococci.

Acetylglucosamine↗