Search PubMed⌕ Search

Biomedical subjects

T Shibata

Publications and source records attributed to T Shibata.

At least 631 records · Page 35Linked to original sources

Genetic polymorphism and close linkage of two plasma protein loci in dogs.

By using a simple method of two-dimensional horizontal electrophoresis, phenotypes of an unidentified plasma protein (PA4) were determined in 967 dogs belonging to 43 different breeds. Two codominant, autosomal alleles (F and S) of PA4 were reported. While many of the breeds of middle and north-eastern Asia (akita inu, Alaskan malamute, chow chow, samoyed, Siberian husky and Tibetan terrier) showed a substantial frequency (0.1 to 0.6) of the S allele, a majority of the European breeds had only the F allele. Evidence was provided that the PA4 locus is closely linked to the plasma pretransferrin 1 locus (PRT1). No recombinant was observed in 45 informative offspring studied. In nearly all breeds, the PA4 S allele was almost always in coupling phase with the PRT1 F allele.

Animals↗

Shedding of CD9 antigen by bone marrow cells from patients with acute lymphoblastic leukaemia.

The levels of soluble CD9 antigen released into spent medium from bone marrow (BM) cells were assayed using a unique enzyme-linked immunosorbent assay. We demonstrated that a considerable amount of soluble CD9 antigen was consistently detected in the spent medium from CD9+ leukaemic blasts, but little from normal or regenerating BM cells. The sensitivity and specificity of CD9 antigen assay were tested. First, BM cells taken from patients in complete morphologic remission (CR) were studied, and the distinct level of CD9 antigen was detected in 16.3% of the cases. Second, the outcome of leukaemic patients with significant shedding of CD9 antigen from BM cells while in CR was investigated: all patients have developed systemic relapse within 5-24 (median 15.4) weeks. In contrast, 24/34 patients without the increase of CD9 antigen levels are still in CR (follow-up 19-149 weeks, median 56.2 weeks). Only 10 patients in this group have relapsed so far. No false-positive results were detected with this sensitive assay for soluble CD9 antigen, and the introduction of appropriately planned prospective studies is justified on the basis of these observations.

Antigens, CD↗

Release of excitatory amino acids from cultured hippocampal astrocytes induced by a hypoxic-hypoglycemic stimulation.

An excess release of excitatory amino acids (EAA) is an important factor for postischemic brain damage. In the present communication, we demonstrate that cultured hippocampal cells release EAA after hypoxic-hypoglycemic treatment. The amounts of EAA released from astrocytes were appreciably above those released from neurons. Furthermore, the amount of aspartate released from astrocytes was comparable to that of glutamate, although the endogenous content of aspartate was one-fifth that of glutamate. The endogenous content of aspartate in astrocytes increased even after hypoxic-hypoglycemic treatment. These results suggests that ischemic neuronal death is due, at least in part, to the excitotoxicity of aspartate and glutamate derived from surrounding astrocytes.

Amino Acids↗

Spectral analysis of 87-lead body surface signal-averaged ECGs in patients with previous anterior myocardial infarction as a marker of ventricular tachycardia.

BACKGROUND: There were few studies on the relation between the body surface distribution of high- and low-frequency components within the QRS complex and ventricular tachycardia (VT). METHODS AND RESULTS: Eighty-seven signal-averaged ECGs were obtained from 30 normal subjects (N group) and 30 patients with previous anterior myocardial infarction (MI) with VT (MI-VT[+] group, n = 10) or without VT (MI-VT[-] group, n = 20). The onset and offset of the QRS complex were determined from 87-lead root mean square values computed from the averaged (but not filtered) ECG waveforms. Fast Fourier transform analysis was performed on signal-averaged ECG. The resulting Fourier coefficients were attenuated by use of the transfer function, and then inverse transform was done with five frequency ranges (0-25, 25-40, 40-80, 80-150, and 150-250 Hz). From the QRS onset to the QRS offset, the time integration of the absolute value of reconstructed waveforms was calculated for each of the five frequency ranges. The body surface distributions of these areas were expressed as QRS area maps. The maximal values of QRS area maps were compared among the three groups. In the frequency ranges of 0-25 and 150-250 Hz, there were no significant differences in the maximal values among these three groups. Both MI groups had significantly smaller maximal values of QRS area maps in the frequency ranges of 25-40 and 40-80 Hz compared with the N group. The MI-VT(+) group had significantly smaller maximal values in the frequency ranges of 40-80 and 80-150 Hz than the MI-VT(-) group. These three groups were clearly differentiated by the maximal values of the 40-80-Hz QRS area map. CONCLUSIONS: It was suggested that the maximal value of the 40-80-Hz QRS area map was a new marker for VT after anterior MI.

Electrocardiography↗

Oily drug carriers in cancer chemotherapy. II. Preparation of viscous ethyl oleate for intraarterial infusion therapy and its disposition in rats and hamsters.

Viscous ethyl oleate (VEO) was prepared as an oil drug carrier by the addition of aluminum stearate or ethyl cellulose. Since the rate of shear of VEO containing aluminum stearate was greatly and nonlinearly changed against the shearing stress compared to that containing ethyl cellulose, the latter was used for subsequent microvascular and organ distribution experiments in rats and hamsters. For infusion into the carotid artery in hamsters, neat ethyl oleate (EO, 4cP) or VEOs of various apparent viscosities (40, 80, 120 cP-VEOs) embolized the vascular system in the cheek pouch, although arrival time to the site where the embolization was observed and the embolization period differed depending on the type of oily drug carrier. For infusion into the hepatic artery in rats, however, only 120 cP-VEO embolized the vascular system in the liver. After infusion of the oily drug carrier containing 3H-oleic acid into the artery of hamster cheek pouch and rat liver, 30-50% of the radioactivity was gradually eliminated within 48 h, whereas about 80% of the dose was rapidly eliminated after infusion to rat stomach and kidney. In addition, the amount of 120 cP-VEO remaining in each organ 48 h after infusion was higher than those of EO and 40 and 80 cP-VEOs. Histological observation after infusion in rat liver revealed that 120 cP-VEO slowly migrated from the artery or arteriole to the sinusoidal capillary region. These results suggest that 120 cP-VEO can be used as a drug carrier because of its function of vascular embolization and high retention in a targeted tissue.

Animals↗

Pseudoaneurysm of the distal aortic arch in Behçet's disease--a case report.

Behçet's disease, manifested as a triform of relapsing iritis, stomatitis and genital ulceration, is now recognized as a systemic vasculitis that affects both veins and arteries. However, aneurysms of the aortic arch associated with Behçet's disease are extremely rare. We report on a successfully resected pseudoaneurysm of the distal aortic arch in a patient with Behçet's disease. The aneurysm was evaluated preoperatively by computed tomography (CT), magnetic resonance imaging (MRI) and intravenous digital subtraction angiography (DSA). We found that these non-invasive methods were quite useful for diagnosing the aneurysm in the aortic arch. Aneurysms enlarge rapidly when coupled with infection and are prone to rupture, thus requiring extensive surgical repair. However, since false aneurysm formations often occur at the site of anastomosis, postoperative follow-up should be monitored very closely.

Adult↗

Histological and histochemical investigations on Japanese lizard esophagus.

The authors previously investigated the bottle-shaped glands distributed in the lamina propria mucosae of the Japanese lizard and gecko. We made two sets of sections of the Japanese lizard at that time. The numerical values of the physical dimensions of the two individuals were as given table 1, showing that No. 2 was slightly smaller. Moreover we found very unusual tissue in the lower portion of the esophagus of No. 2. Therefore we excluded this individual from the preceding investigations. However, we made various observations, and the results of these investigations are as follows. 1. The lumen of the upper portion of the esophagus has no fold. However, the middle and lower portions formed very complicated folds. Therefore, the lumen was remarkably narrow. 2. The epithelium of the esophageal mucous membrane consisted of simple columnar cells and throughout each part, reacted strongly to PAS and moderately to AB (pH 2.5 and 0.5). It presented a dark blue (R18-B13 of Blue-Purple-Red) color in response to PAS-AB (pH 2.5) and contained no pepsinogen granules. The esophageal upper portion of small individuals only exhibited the PAS reaction in this investigation. 3. A number of bottle-shaped glands were distributed in the lamina propria mucosae of the lower portion of the esophagus of each material. The glandular cells in the basal portion were most differentiated and contained a great number of pepsinogen granules. 4. The above-mentioned glands were extremely simple and glands of this type could not be found in textbooks and theses. Accordingly, we previously described them with the tentative name of shimple branched tubular glands, but subsequently found this to be erroneous. We assume that these glands are esophageal gastric glands. 5. Compound tubular glands are formed in the lamina propria mucosae of the human esophagus, but do not exist in the Japanese macaque, crab-eating monkey, horse, cow, swine, dog, cat, rabbit, mouse and rat. Dellmann-Brown also described the absence of such glands in the esophagus of the horse, swine, cow, goat, sheep, dog and cat. 6. We subsequently found compound tubular glands distributed in the lamina propria mucosae of the fowl, goose and wild duck esophagus. They similarly secreted pepsinogen granules. 7. We assume that these glands of the Japanese lizard and gecko have a phylogenic relation with the glands in the bird. The pepsinogen-granule-secreting cells in the snake do not extend into the lamina propria mucosae.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

A new angiogenesis inhibitor, FR-111142.

FR-111142 is a new angiogenesis inhibitor produced by a fungus Scolecobasidium arenarium F-2015. FR-111142 inhibited endothelial cell proliferation in vitro and angiogenesis in the growing chick chorioallantoic membrane model in vivo. Further, FR-111142 also suppressed the solid tumor growth in mice.

Allantois↗

Effects of calmodulin inhibitors on amylase secretion from rat pancreatic acini.

To investigate the role of calmodulin in stimulus-secretion coupling in pancreatic acinar cells, we studied the effects of W-7, a calmodulin inhibitor, and KN-62, a specific inhibitor of Ca2+/calmodulin-dependent protein kinase II (Ca2+/CaM kinase II), on amylase secretion from rat pancreatic acini. Calmodulin inhibitor (W-7, 100 microM) and Ca2+/CaM kinase II inhibitor (KN-62, 10 microM) reduced amylase secretion stimulated by cholecystokinin (CCK) or carbachol. W-7 and KN-62 also inhibited amylase secretion stimulated by both calcium ionophore (A23187) and phorbol ester (12-O-tetradecanoylphorbol-13-acetate, TPA). To clarify the role of calmodulin in the interaction of intracellular mediators, pancreatic acini were permeabilized with streptolysin O. Following permeabilization, amylase secretion was stimulated by submicromolar free Ca2+, and this Ca(2+)-dependent amylase secretion was enhanced by guanosine 5'-[gamma-thio]triphosphate (GTP gamma S), TPA or cyclic adenosine 3',5'-monophosphate (cAMP). W-7 and KN-62 had no effects on amylase secretion stimulated by Ca2+ alone, but inhibited the enhancement in Ca(2+)-dependent amylase secretion by GTP gamma S, TPA or cAMP. These data suggest that calmodulin plays an important role in Ca(2+)-dependent amylase secretion from pancreatic acinar cells and in the interaction between Ca2+ and other intracellular messengers.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

[Analysis of the regulation of HLA class II genes by forskolin].

The expression of HLA class II molecules is mainly regulated transcriptionally and this regulation is thought to play an important role to the control of immune response. In this report, we have studied the effect of adenylate cyclase activator, forskolin, to the expression of HLA class II molecules on the cell surface of an human multiple myeloma cell line, RPMI8226. On the northern blot analysis and FACS analysis, we have revealed that forskolin upregulated the expression of mRNAs of DQB and DRB gene and their products on its surface. On the sequence analysis of upstream of HLA-DQB gene, we have identified not only Y-,X-, W-box, which were thought to regulatory region of truncated gene, but also cAMP responsible element (CRE) like regulatory region, which located upstream of W-box. On the gel retardation assay, when we used DNA probes that were specific for CRE like region and Y-box, we have found newly detectable bands, which appeared by forskolin treatment. These data suggest that forskolin upregulates HLA class II molecules by means of the interaction between CRE and cAMP responsible element binding protein (CREB).

Colforsin↗

[Estimated production of coal-tar dyes (including dye aluminum lakes) based on official inspections in 1991].

The total number of official inspection of coal-tar dyes and their lakes from April in 1991 to March 1992 was 835. The quantity which passed inspection amounted to 240 tons in Japan. The official production of color dyes each month in summarised in Table 1 and that by various manufacturers in Table 2. The food coal-tar dye produced in the largest quantity was Food Yellow No. 4, occupying 44.6% of the total during this period.

Chemical Industry↗