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T Shibuya

Publications and source records attributed to T Shibuya.

At least 199 records · Page 11Linked to original sources
PubMed1993

[Eosinophilic response in parasitic diseases].

The increase of eosinophiles in peripheral blood and in the lesion is characteristic feature of many parasitic diseases. Those parasites which invade host organs generally cause eosinophilia of high degree. Thus, zoonotic parasites belonging to genuses gnathostoma, paragonimus and angiostrongylus etc. bring about continuous hypereosinophilic response due to lasting larval migration, but in contrast, those which migrate temporarily during the developmental stage in the host, cause transient eosinophilia, as in Loeffler's syndrome, due to round worms. In contrast, those parasites which live in the luminal organ and never invade tissues, may not cause eosinophilia. The variety of patterns in eosinophile response is outlined together with some clinical data.

Animals↗
PubMed1993

Penetration of Schistosoma mansoni cercariae into a living skin equivalent.

We evaluated the use of a living skin equivalent (LSE) as a suitable membrane for Schistosoma mansoni cercarial penetration. LSE is a living artificial skin composed of a dermal layer containing human dermal fibroblasts embedded in a collagen lattice and an epidermal layer consisting of differentiated human keratinocytes. The keratinocytes differentiate into a stratum corneumlike layer, whereas the dermal-epidermal junction forms a layer similar, but not identical to, the basement membrane. We exposed LSE to 50 cercariae for 0, 3, 6, 20, and 30 hr at 37 C, and the percentage of penetration was evaluated by counting cercariae remaining on the LSE surface. No cercarial penetration was observed in the first 15 min of exposure; however, penetration was detected at all other times. Maximum penetration rates were observed at 20 hr (80%). In other experiments LSE was pretreated topically with 0 or 4 micrograms/cm2 linoleic acid, then exposed to between 800 and 1,000 cercariae for 18-20 hr at 37 C. LSE pretreated with linoleate had significantly higher penetration rates than untreated membranes (81% +/- 2.51% vs. 65.9% +/- 6.97%, P = 0.03). Increasing linoleate concentrations from 10 to 40 micrograms/cm2 gradually decreased the ability of cercariae to penetrate the membrane. Some LSE membranes also were processed for light microscopy, and we present photomicrographs showing schistosomulae within the epidermal and dermal layers of the LSE. We conclude that despite the time it takes for cercariae to penetrate LSE, these membranes may allow investigators to examine, in vitro, host-parasite interactions at the level of the skin.

Animals↗
PubMed1992

Long-lasting excitation of protocerebral bilateral neurons in the pheromone-processing pathways of the male moth Bombyx mori.

Intracellular recording and staining with Lucifer yellow were used to characterize the responses and structure of pheromone-processing bilateral neurons in the protocerebrum of the brain of the male silkworm moth Bombyx mori. Numerous olfactory bilateral neurons innervated a particular neuropil region lateral to the central body, the lateral accessory lobe (LAL). The LALs are linked to each other by bilateral neurons with arborizations in each LAL. The LAL appears to be important for collecting the olfactory information from both sides of the brain. Many of the bilateral neurons showed a characteristic long-lasting excitation (LLE) that outlasted the olfactory stimuli (1.5 s). In some preparations, the LLE lasted more than 20 s and the firing gradually decreased to the background level.

Animals↗
PubMed1992

Angioscopic evaluation of coronary-artery thrombi in acute coronary syndromes.

BACKGROUND: Disruption of an atherosclerotic plaque in a coronary artery followed by the formation of a thrombus is believed to be the cause of both unstable angina and acute myocardial infarction. Although thrombolytic therapy is efficacious in patients with acute myocardial infarction, for unknown reasons it is far less effective in patients with unstable angina. We postulated that there might be differences in the composition of the coronary-artery thrombi in unstable angina and acute myocardial infarction. METHODS: To investigate the appearance of coronary-artery thrombi, we performed percutaneous transluminal coronary angioscopy in 15 patients with unstable angina and 16 with acute myocardial infarction. Angioscopy was performed within 48 hours after an episode of pain at rest in the patients with unstable angina and within 8 hours of onset in those with acute myocardial infarction. RESULTS: Angioscopy revealed coronary thrombi in all but two patients (one in each group). Of the 29 patients with thrombi, those with unstable angina were frequently observed to have grayish-white thrombi (10 of 14, 71 percent), but none were seen in the 15 patients with acute myocardial infarction (P less than 0.01). By contrast, reddish thrombi were observed in all 15 patients with acute myocardial infarction who had thrombi, but in only 4 of the 14 patients with unstable angina and thrombi (P less than 0.01). As assessed by coronary angiography, occlusive thrombi occurred frequently in patients with acute myocardial infarction (13 of 16 patients) but were not seen in any of the 15 patients with unstable angina (P less than 0.01). CONCLUSIONS: Coronary-artery thrombi play an important part in the pathogenesis of unstable angina and acute myocardial infarction. However, the appearance of the thrombi is different in the two conditions, possibly reflecting differences in the composition of age of the thrombi or the presence or absence of blood flow in the artery. This difference may account for the contrasting results of thrombolytic therapy.

Angina Pectoris↗
PubMed1992

CD7-positive acute myeloid leukemia: further evidence of cellular immaturity.

Among 63 cases of acute myeloid leukemia (AML), 14 were found to express the CD7 antigen, a cell surface marker usually found at an early stage during T lineage differentiation. The CD7-positive AML cases consisted of 5 cases of M1, 3 cases of M2, 3 cases of M4, 1 case of M5, 1 case of M6 and 1 case of M7. Among these 63 cases, the proportion of blast cells expressing the CD34 antigen was examined. The proportion of CD34-stained cells among the CD7-positive AML cases, although varying, was significantly larger than that among the CD7-negative AML cases (P less than 0.05). As the CD34 antigen was expressed on hematopoietic progenitor cells and was considered to reflect an early hematopoietic stage, the high proportion of cells expressing CD34 among the CD7-positive AML cases may support the notion that CD7-positive AML cells are immature.

Adolescent↗
PubMed1992

Use of a synthetic protease inhibitor for the treatment of L-asparaginase-induced acute pancreatitis complicated by disseminated intravascular coagulation.

In two patients receiving L-asparaginase therapy, severe acute pancreatitis complicated by disseminated intravascular coagulation (DIC) developed. In both cases it was successfully treated with continuous infusion of a synthetic protease inhibitor, nafamostat mesilate. In this report, we briefly discuss the clinical efficacy of the synthetic protease inhibitor in treating such cases.

Acute Disease↗
PubMed1992

Influence of substituting B2O3 for CaF2 on the bonding behaviour to bone of glass-ceramics containing apatite and wollastonite.

Glass-ceramics containing crystalline oxy-fluoroapatite (Ca10(PO4)6(O,F2)) and wollastonite (CaSiO3) (designated AWGC) are reported to have a fairly high mechanical strength as well as the capability of forming a chemical bond with bone tissue. The chemical composition is MgO 4.6, CaO 44.9, SiO2 34.2, P2O5 16.3, and CaF2 0.5 in weight ratio. In this study the influence of substituting B2O3 for CaF2 on the bonding behaviour of glass-ceramics containing apatite and wollastonite to bone tissue was investigated. Two kinds of glass-ceramics containing apatite and wollastonite were prepared. CaF2 0.5 was replaced with B2O3 at 0.5 and 2.0 in weight ratio (designated AWGC-0.5B and AWGC-2.0B). Rectangular ceramic plates (15 x 10 x 2 mm, abraded with No. 2000 alumina powder) were implanted into a rabbit tibia. The failure load, when an implant detached from the bone, or the bone itself broke, was measured. The failure load of AWGC-0.5B was 8.00 +/- 1.82 kg at 10 weeks after implantation and 8.16 +/- 1.36 kg at 25 weeks after implantation. The failure load of AWGC-2B was 8.08 +/- 1.70 kg at 10 weeks after implantation and 9.92 +/- 2.46 kg at 25 weeks after implantation. None of the loads for the two kinds of glass-ceramics decreased as time passed. Giemsa surface staining and contact microradiography revealed direct bonding between glass-ceramics and bone. SEM-EPMA showed a calcium-phosphorus rich layer (reaction zone) at the interface of ceramics and bone tissue. The thickness of the reaction zone was 10 to -15 microns and did not increase as time passed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Biological characteristics of CD7 positive acute myelogenous leukaemia.

We studied the biological characteristics of CD7+ acute myelogenous leukaemia (AML). We diagnosed nine out of 88 consecutive AML cases as CD7+ AML based on myeloperoxidase positivity and surface antigen expression. In eight of these nine cases more than 20% of leukaemic blasts were found to coexpress both CD7 and a myeloid-associated antigen, CD33, by a two-colour flow-cytometric assay, while in the remaining case more than 90% of blasts were positive for CD7 and myeloperoxidase. CD7+ AML was most frequently observed in M1 among AML subtypes according to the FAB classification. An early stage-specific antigen, CD34 was also expressed on leukaemic blasts from eight of these nine cases. Neither the T-cell receptor (TcR)-beta nor the TcR-gamma gene was clonally rearranged in any of the cases. We then studied the proliferative responses to stimulation by various growth factors. Among interleukin-3 (IL-3), granulocyte/macrophage colony-stimulating factor (GM-CSF), and granulocyte-CSF (G-CSF), IL-3 showed the strongest stimulatory effect on DNA synthesis and leukaemic blast colony formation in 8/9 and 6/8 CD7+ AML cases examined, respectively. On the other hand, the strongest stimulatory effect exerted by IL-3 on blast colony formation was observed in only six out of the 33 CD7- AML cases examined. Furthermore, CD7+ AML blasts could proliferate in response to stem cell factor (SCF); SCF alone showed stimulatory effects on blast colony formation (7/8 cases), and in 5/7 SCF-responding cases, stimulatory effects of SCF were more potent than those of IL-3. In addition, SCF enhanced blast colony formation synergistically with IL-3 in four of these seven cases. These data suggest that progenitor cells of CD7+ AML may possess the biological properties characteristic of immature haematopoietic stem cells.

Adolescent↗
PubMed1992

Interstitial 9q deletion in T-lymphoid/myeloid biphenotypic leukaemia.

We report the biological characteristics of leukaemic blasts from two cases of acute leukaemia with an interstitial deletion of the long arm of chromosome 9 (9q-). Case 1 (FAB: M1) showed del(9)(q12q22) as the sole karyotypic anomaly, and case 2 (FAB: M1) presented del(9) (q12q22) in association with trisomy 10. In both cases, leukaemic blasts presented unique cytological features, such as prominent vacuoles on Giemsa staining, or strong localization of myeloperoxidase resembling 'pseudo-Chediak-Higashi' granules. Immunophenotyping of blasts revealed the biphenotypic expression of T-lymphoid/myeloid antigens (CD2, CD7/CD33) in addition to CD34. Neither T-cell receptor beta (TCRB), T-cell receptor gamma (TCRG) nor Ig heavy chain (IGH) genes were clonally rearranged. Furthermore, there was neither rearrangement nor expression of ABL, which is located at 9q34, indicating that the deletion involved bands centrometric to 9q34 did not induce the activation of ABL. DNA synthesis of the blasts was stimulated (stimulation index greater than 2.0) in the presence of interleukin (IL)-3, IL-4, granulocyte colony-stimulating factor or erythropoietin (Epo). IL-3 and IL-4 could also support the in vitro growth of leukaemic blast colonies, and the IL-3- or IL-4-dependent blast colony growth was synergistically enhanced by the addition of IL-6 or Epo. These observations imply that T-lymphoid/myeloid or pluripotent stem cells may be closely involved in the development of 9q- AML.

Adolescent↗
PubMed1992

Acquired von Willebrand's disease in association with essential thrombocythemia: regression following treatment.

Acquired von Willebrand's disease in a 40-year-old woman affected with essential thrombocythemia (ET) is reported. The profile of plasma von Willebrand factor (vWF) revealed decreased ristocetin cofactor activity and diminished large multimers of vWF in spite of a normal vWF antigen level. There was no evidence of circulating inhibitor against the factor VIII complex. The vWF abnormality improved by controlling the platelet count following treatment for ET with interferon-alpha 2b and ranimustine. The possible mechanism of the development of AvWD in ET is briefly discussed.

Adult↗
PubMed1992

Successful treatment of chronic adult T-cell leukemia with ubenimex.

A 38-year-old Japanese man had suffered from trichophyton infection for several years. The white blood cell count was 20,300/mm3, including 54% abnormal lymphocytes with irregularly convoluted nuclei. Adult T-cell leukemia (ATL) was diagnosed based on proliferation of CD4-positive lymphocytes, positive anti-HTLV-I antibody and monoclonal integration of proviral DNA. By 30 mg/day of ubenimex (Bestatin), the abnormal lymphocytes positive for CD4 in the peripheral blood were gradually reduced. Complete remission was maintained for 9 months without any antineoplastic agents. Ubenimex may have suppressed the growth of ATL cells in this patient. Accordingly, ubenimex may prove useful for treating some patients with chronic-type ATL.

Adult↗
PubMed1992

Deficiency of coagulation factor XIII A subunit caused by the dinucleotide deletion at the 5' end of exon III.

A congenital deficiency of the coagulation Factor XIII A subunit (F XIII A) is a rare autosomal recessive disorder that is characterized by a life-long bleeding tendency complicated by a difficulty in healing. Thus far, no molecular genetic analysis of this disorder has been reported. In this study, we demonstrate the molecular abnormalities in a family with this disorder. We performed Northern blot analysis of peripheral blood monocytes obtained from the propositus and found a 4-kb single band of F XIII A mRNA whose size was identical with that of normal subjects. Exons II-XV, which encode all the amino acids, were individually amplified by a polymerase chain reaction (PCR). All PCR products from the propositus had lengths indistinguishable from those of the wild type on agarose gel, suggesting that this defect results from either a point mutation or a short deletion/insertion. The sequencing of F XIII A cDNA from the propositus revealed a deletion of the dinucleotide AG within the AGAG repeat at the position of 210 to 213. Concerning the genomic sequence, a deletion of dinucleotide AG was also demonstrated in the intron B-exon III boundary. This deletion appeared to cause a frameshift mutation making a new stop codon shortly thereafter, and leading to a deficiency of plasma F XIII A. The heterozygosity of the F XIII A deficiency in the patient's offspring was documented by the nucleotide sequences of their exon III.

Alleles↗
PubMed1992

The pathogenesis of an impending infarction and its treatment--an angioscopic analysis.

To clarify the pathogenesis of an impending infarction and to investigate the difference between the pathogenesis of an acute myocardial infarction and an impending infarction, we have performed percutaneous transluminal coronary angioscopy in 13 patients with an impending infarction and in 13 patients with an acute myocardial infarction. As a result, coronary thrombi were observed in 12 of the 13 patients with an impending infarction, and a similar frequency of thrombi was observed in the patients with an acute myocardial infarction. Further, grayish white thrombi were observed in 9 of 12 patients with an impending infarction, but no such thrombi were noted in those with an acute myocardial infarction. Reddish thrombi, however, were observed in all patients with acute myocardial infarction, whereas such thrombi were observed in only 3 of 12 patients with an impending infarction. Informatively, occlusive thrombi occurred more frequently in patients with an acute myocardial infarction than in those with an impending infarction. As a thrombus plays an important role in an impending infarction, we also evaluated the effect of anticoagulant and thrombolytic therapy for an impending infarction in 79 patients. The incidence of recurrent angina and a subsequent acute myocardial infarction were significantly higher in non-heparin-treated patients and in thrombolytic-treated patients than in heparin-treated patients. In conclusion, a thrombus plays an important role in the pathogenesis of an impending infarction and in an acute myocardial infarction, though the characteristics of the thrombus differ in each instance. This difference may account for the differing results of thrombolytic therapy. Heparin was found an effective treatment for myocardial ischemia in an impending infarction.

Angioscopy↗
PubMed1992

The effectiveness of coronary angioscopy in detecting intraluminal pathologic changes.

We have evaluated the feasibility of percutaneous transluminal coronary angioscopy for detecting intraluminal pathological changes as a diagnostic tool, and investigated the pathogenesis of two acute coronary disorders, acute myocardial infarction and unstable angina. Twelve patients with an acute coronary disorder and 20 patients who underwent percutaneous transluminal coronary angioplasty were selected for this comparison between the diagnostic accuracy of angioscopy and arteriography. One hundred and thirty patients were investigated by angioscopy as follows in order to investigate the pathogenesis of their acute coronary disorders: 22 within 8 h of onset acute myocardial infarction; 28 from one day to 2 months since onset recent myocardial infarction; 37 with an old myocardial infarction; 26 with unstable angina; and 23 with stable angina. Our results have indicated thrombi were detected more frequently by angioscopy than by arteriography (p less than 0.01). Also, thrombi, intimal irregularities, and xanthomatous atheromas were observed more frequently in patients with acute myocardial infarction, recent myocardial infarction, and unstable angina. It is concluded that coronary angioscopy is a much more sensitive method for detecting intraluminal changes, and that a thrombus overlying a rupture in the lining of plaque plays a major role in an acute coronary disorders, and that the fragile, lipid-rich gruel atheroma may precede its rupture.

Coronary Angiography↗