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The presence of a novel member of serine proteinase inhibitor, B-43, was immunohistochemically indicated in both neurons and astrocytes in the parietal region of the bovine brain. B-43-like immunoreactivity was detected in pyramidal cells in the cortex and GFAP-positive astroglial cells in the white matter. The processes of B-43 may play a cooperative role with glia-derived nexin/protease nexin-1 and alpha 1-antichymotrypsin in the brain.
[D-Ala2,MePhe4,Gly(ol)5]enkephalin (DAGO) (10 ng/0.5 microliters saline solution) injected into the tuberomammillary nucleus (TM) of rats in minute amounts decreased the amount of histamine released to approximately 50% of the basal value on measurements taken 20-40 min after administration. This effect of DAGO was inhibited by the simultaneous microinjection of naloxone (320 ng). These results may be explained in two ways. The first is that the stimulation of mu-receptors results in the inhibition of histaminergic cell bodies. The second is that the somatodendritic release of histamine was increased by the stimulation of mu-receptors and as a result of increased histamine concentration in TM, many histaminergic neurons may be inhibited through the stimulation of H3-receptors. Further studies are necessary regarding the influence of mu-agonists on various cellular sites of histaminergic neurons.
The novel alkaline amylopullulanase produced by alkalophilic Bacillus sp. KSM-1378 was purified to an electrophoretically homogeneous state from culture medium. The purified enzyme was a glycoprotein with an apparent molecular mass of about 210 kDa and an isoelectric point of pH 4.8. The N-terminal amino acid sequence was Glu-Thr-Gly-Asp-Lys-Arg-Ile-Glu-Phe-Ser-Tyr-Glu-Arg-Pro and showed no homology to the N-terminal regions of other amylopullulanases reported to date. The enzyme was able to attack specifically the alpha-1,6 linkages in pullulan to generate maltotriose as the major end product, as well as the alpha-1,4 linkages in amylose, amylopectin and glycogen to generate various oligosaccharides. The pH and temperature optima for the pullulanase and alpha-amylase activities were pH 9.5 and 50 degrees C and pH 8.5 and 50 degrees C respectively. Both activities were strongly inhibited by well characterized inhibitors, such as diethyl pyrocarbonate and N-bromosuccinimide. The pullulanase activity was specifically inactivated by Hg2+ ions, alpha-cyclodextrin and beta-cyclodextrin while the amylase activity was strongly inhibited by EDTA and EGTA, although inhibition could be reversed by Ca2+ ions. It is suggested that the single alkaline amylopullulanase protein has two different active sites, one for the cleavage of alpha-1,4-linked substrates and one for the cleavage of alpha-1,6-linked substrates.
The permeation of macromolecular FITC-labeled dextran (molecular weight 70,000) through bovine aortic endothelial cells (BAEC) monolayer, which were cultured for 5 days with conditioned medium prepared from mouse melanoma B16, was increased. However, when BAEC, which were cultured with normal medium until confluent, were treated with B16 conditioned medium (B16-CM) for 30 min, the permeability did not increase. The B16-CM also increased the permeability of the endothelial monolayers of bovine veins and the human umbilical vein, but did not increase that of the epithelial monolayer. The B16-CM did not alter the distribution or content of F-actin on the BAEC. BAEC cultured in the presence of B16-CM for 5 days were detached from the dish, and then seeded into a chamber at one-fifth of confluent cell density. After 5 days of culture in normal medium, the BAEC were grown to confluence and their permeability was increased. These findings suggest that B16-CM increased the endothelial permeability irreversibly without the decrease of F-actin, and that soluble factor(s) which were secreted from the tumor cells participate in the construction of the hyperpermeable structure of tumor vessels in vivo.
The macromolecular permeability of cultured bovine aortic, bovine venous, and human umbilical vein endothelial cell monolayers was decreased significantly in culture medium containing L-ascorbic acid (Asc Acid; 0.01-0.1 mM) and L-ascorbic acid 2-phosphate (Asc 2-P). Dithiothreitol, which shows reducing activity equivalent to that of Asc Acid, did not affect endothelial permeability. Asc Acid induced a sixfold increase in collagen synthesis by the endothelial cells. The coexistence of L-azetidine 2-carboxylic acid, an inhibitor of collagen synthesis, attenuated the effect of Asc 2-P in a dose-dependent manner. Another collagen synthesis inhibitor, ethyl-3,4-dihydroxybenzoate, also inhibited collagen synthesis and increased endothelial permeability. The decrease in permeability of the endothelial monolayer was dependent on a reduction of the permeability coefficient of the endothelial monolayer. These findings indicate that endothelial barrier function is stimulated by Asc Acid via an increase in collagen synthesis.
The development of a sensitive enzyme immunoassay for endothelin is described. This assay is based on a sandwich method using two different monoclonal antibodies against endothelin-1. A monoclonal antibody, which reacted to the C-terminal region of endothelin, was selected as an immobilized antibody. The Fab' fragment of another monoclonal antibody, which might recognize the N-terminal rigid region of endothelin, was used as a horseradish peroxidase-labeled detector antibody. The assay measures endothelin-1 and endothelin-2 with a sensitivity of 1 fmol/ml. We have determined that cultured endothelial cells actually produced endothelin in significant amounts in a time-dependent manner. The levels of plasma endothelin extracted with Sep-Pak tC18 light cartridges could also be monitored. A basal endothelin level was about 0.3 fmol/ml of plasma, and a transient increase was observed 4 h after starting blood collection under in vivo experimentation in the rat. This enzyme immunoassay will facilitate the investigation of physiological roles of endothelin.
BACKGROUND: Seroprevalence of antibody to human T-lymphotropic virus type I (HTLV-I) is high in the island of Kyushu, Japan. Reports on the etiological analysis of HTLV-I in patients with uveitis primarily document cases in this island. We studied the seroprevalence of HTLV-I at the Department of Ophthalmology in Yokohama City University Hospital and in Odawara Municipal Hospital, which are in the Kanto Plain on the island of Honshu, Japan. METHODS: The subjects were 741 patients who visited the two hospitals. The presence of serum antibodies against HTLV-I was assessed using the method of particle agglutination. RESULTS: Of 454 patients with nonuveitic ocular diseases, 9 (1.98%) were seropositive. Of 143 patients with definite diagnosis of uveitis, 1 (0.70%) was seropositive. Of 144 patients with non-specific uveitis (etiology undefined), 8 (5.56%) were seropositive. Thus, the prevalence of serum antibodies to HTLV-I was higher in patients with non-specific uveitis than in patients with specific uveitis or nonuveitic ocular diseases. Common ocular symptoms of 8 HTLV-I-infected patients with non-specific uveitis were compatible with the clinical features of uveitis described as HTLV-I-associated uveitis (HAU). CONCLUSION: It is important to suspect HAU in patients with uveitis of unknown etiology, even outside known areas of prevalence.
The present study was conducted to examine the effects of heparin, sperm concentration and bull variation on the fertilization of bovine oocytes in a protein-free medium supplemented with polyvinyl alcohol and subsequent in vitro development of fertilized embryos. The effects in protein-free medium were compared with those in medium supplemented with bovine serum albumin (BSA). In the presence of heparin (1, 10 and 100 microg/ml), nearly all the oocytes were fertilized with and without BSA. In the absence of BSA, polyspermy was lower (4 to 15%) than in its presence (15 to 48%; P < 0.05). An increase in sperm concentration from 1 x 10(4) cells/ml during insemination enhanced fertilization rate up to 1 x 10(6) cells/ml with and without BSA (14 to 90% and 3 to 77%, respectively). In the absence of BSA, the highest concentration of spermatozoa (1 x 10(7) cells/ml) gave a lower fertilization rate (55%) than that at 1 x 10(6) cells/ml (77%; P < 0.05). Polyspermy neither increased nor decreased sperm concentration without BSA (0 to 8%; P > 0.05). The effects of spermatozoa from 5 different bulls chosen randomly on in vitro fertilization in medium without BSA were examined. Individual bull variation in fertilization rate (36 to 95%) was noted at 3 different heparin concentrations (1, 10 and 100 microg/ml). Polyspermic fertilization was low (0 to 14%) and was the same for all bulls at all heparin concentrations. Embryos fertilized without BSA developed to the blastocyst stage at the same rate (27%) as those with BSA (33%; P > 0.05).
Examination was made of the effects of water quality in medium preparation on fertilization and early development of bovine in vitro matured (IVM) oocytes in a protein-free medium. The IVM oocytes were inseminated and cultured for 7 d in protein-free media prepared with 4 different types of water preparations: tap, deionized, twice-distilled, and purified water using the Milli-Q system (Milli-Q water). High frequencies (70 to 83%) of normal fertilization were obtained in media prepared with all types of water. However, the frequency of development to the blastocyst stage in media prepared with Milli-Q water (31 +/- 3%) was significantly higher than with the 3 other types of water (11 to 13%). Moreover, the effects of storage period of Milli-Q water on early development of bovine embryos was also examined. The frequency of development to the blastocyst stage in media prepared with Milli-Q water immediately after preparation (fresh Milli-Q water; 35 +/- 4%) was significantly higher than for Milli-Q water stored for 1 wk (18 +/- 4%) or 2 wk (18 +/- 3%). Effects of commercially available purified water on early development of bovine embryos were also examined. The frequency of development to the blastocyst stage in media prepared with Milli-Q water (33 +/- 5%) was significantly higher than for purified water purchased from 3 different suppliers (Brand A; 21 +/- 6%, Brand B; 21 +/- 2%, Brand C; 21 +/- 4%). Each water sample was analyzed by the measurement of electrical conductivity, organic compounds and/or inorganic ion and endotoxin concentrations to evaluate purity. Fresh Milli-Q water showed the lowest level of electrical conductivity and contained the lowest concentration of organic compounds. These results indicate that in vitro fertilization of bovine oocytes is not affected by the water quality in the preparation of medium; however, early development of bovine embryos is seriously affected by the purification method and the storage period of water used for medium preparation.
We purified a novel serine proteinase inhibitor (serpin)-like protein from the bovine brain and named it B-43 from its molecular mass, 43 kDa. A cleaved peptide from B-43 was copurified with the native B-43. Partial amino acid sequencing of the purified B-43 showed that this protein was homologous to glia-derived nexin/protease nexin-1 (GDN/PN-1), plasminogen activator inhibitor 2, leukocyte elastase inhibitor (LEI) and placental thrombin inhibitor (PTI) among the serpins. Although B-43 had a similar amino acid composition to these serpins, the biochemical features of B-43 were different from them. B-43 did not form sodium dodecyl sulfate (SDS)-resistant serpin-proteinase complexes with thrombin, urokinase, pancreatic elastase and plasmin, suggesting that these proteinases were not the targets of B-43. In contrast to GDN/PN-1, B-43 did not have an affinity for heparin. B-43, having different biochemical properties from GDN/PN-1, appears to be an additional serpin expressed in the brain.
We have investigated the effect of methanol at concentrations below 15% (v/v) on acto-heavy meromyosin (HMM)- and tropomyosin (Tm)-troponin (Tn)-acto-heavy meromyosin-ATPase activities. Methanol slightly enhanced ATPase activity of acto-HMM alone. It had no apparent effect on normalized Tm-Tn-acto-HMM-ATPase activity in the absence of Ca2+. In the presence of Ca2+, however, methanol markedly inhibited normalized Tm-Tn-acto-HMM ATPase activity. These results show that methanol affects the troponin-tropomyosin regulation of acto-HMM ATPase: methanol suppresses the Ca(2+)-sensitivity of the regulatory system and traps it in an "off-state."
AIMS/BACKGROUND: Recently HTLV-I has been shown to cause a kind of endogenous uveitis in south west Japan, where HTLV-I infection is highly endemic. To investigate further the association of HTLV-I infection with the incidence of this uveitis, HTLV-I seroprevalence in central Japan, where HTLV-I infection is not endemic, was studied. METHODS: HTLV-I seroprevalence was investigated in 1579 patients with various ocular diseases and 1251 normal volunteers as a younger control group. Then HTLV-I seroprevalence was compared in each group. RESULTS: Of 1579 patients with various ocular diseases, 38 (2.41%) were seropositive. There was a statistically significant difference in HTLV-I seroprevalence between the undefined uveitis group and non-uveitic ocular diseases group (p < 0.05, Yates's correction). However, the seroprevalence in younger patients with undefined uveitis did not differ significantly from that in other groups. As regards the incidence of this type of uveitis, six of 12 (50%) seropositive patients, who were born in south west Japan and had lived in this area for 35 years, developed this undefined uveitis whereas only two of 26 (7.69%) seropositive patients in the other areas in Japan developed this uveitis. The difference was statistically significant (p < 0.05, Fisher's exact probability test). CONCLUSION: These results suggest that the incidence of this type of endogenous uveitis could be greatly influenced by environmental or hereditary factors including HLA.
An amyloid-like isoform of a 33- to 34-kD glycoprotein, termed as the scrapie prion protein (PrPsc), plays a critical role in transmissible spongiform encephalopathies of animals and humans. It has even been suggested to present the responsible infectious agent. This protein is a posttranslationally modified form of the cellular isoform of prion protein (PrPc). Hitherto, little has been known about the functions of PrPc. In order to examine the localization of PrPc mRNA in rat tissues, the in situ hybridization technique was performed. In rat brain, PrPc mRNA was predominantly localized within pyramidal cells of the hippocampus, large neurons of the thalamus and neocortex, and Purkinje cells of the cerebellum. In the placenta, not only PrPc mRNA was localized to a subpopulation of decidual cells at the highest levels, it was also expressed in the amnion and mesodermal layer of the yolk sac. Furthermore, PrPc mRNA was also expressed in the myometrium of the uterus and seminiferous tubule in the testis. However, signals were not obtained in the lung, spleen, liver of prenatals and other fetus tissues. The distribution of rat PrPc mRNA portrayed the levels which were different among the various types of cells, suggesting that its expression may be regulated in a tissue-specific manner.
Cell cycle kinetics of childhood acute leukemia were determined by the in vitro labeling of marrow blast cells with bromodeoxyuridine (BrdUrd) and subsequent flow cytometry of BrdUrd/DNA and Ki67/DNA in 18 patients with acute lymphocytic leukemia (ALL) and eight patients with acute nonlymphocytic leukemia (ANLL). The BrdUrd-labeling index (BrdUrd-LI) and the duration of S phase (Ts) were calculated from the slope of the regression line obtained by plotting the serial labeling indices against the labeling time. The Ts and potential doubling time (DTpot) of marrow leukemia cells varied from 6.1 to 34.3 h (median 14.3 h) and 1.1 to 20.7 days (median, 7.3 days), respectively. The duration of the total cell cycle time (Tc) which was determined by the Ki-67-derived growth fraction (Ki-67-GF) varied from 14.0 to 112.5 h (median 43.2 h). BrdUrd-LI, DTpot, Ki-67-GF and Tc were significantly correlated with the subtypes (early B-ALL, T/B- ALL and ANLL) of the disease. The median values of LI and GF were much lower in ANLL than in ALL. However, the low proliferative activity of ANLL was not accompanied by a prolonged duration of the total cell cycle time. The longest median duration of Tc was noted in early B-ALL (75.2 h) and the median Tc in ANLL (36.7 h) was close to that in T/B-ALL (34 h). Ts appeared to be rather independent of subtypes of the disease. These results show that there are distinct in vitro growth characteristics in relation to the subtypes of childhood acute leukemia.
We describe five cases of segmental arterial mediolysis (SAM), formerly known as segmental mediolytic arteritis. SAM occurs in epicardial coronary arteries and in the abdominal splanchnic arteries. Patients with abdominal SAM are generally elderly, whereas coronary SAM presents in neonates, children, and young adults. SAM is initiated by mediolysis of the outer media, which can expand to involve the mid- and inner media. Accompanying alterations include fibrinous linear deposits at the medial adventitial junction and replacement of the lysed muscle fibers by fibrin, erythrocytes, and granulation tissue. Transmural mediolysis results in arterial wall gaps frequently complicated by dissecting hematomas and aneurysms. Abdominal hemorrhages stem from these complications. SAM involving abdominal splanchnic arteries clinically presents with abdominal pain and distension, falling hematocrit, and shock. Simultaneous involvement of more than one abdominal artery is frequent, and branches of the celiac axis are most commonly affected. Various disease states that provoke pathologic stimuli for endothelial mediated vasoconstriction occur in the immediate clinical background of patients with SAM. Certain morphologic features of SAM suggest that this arterial lesion is due to vasospasm, which we putatively ascribe to focal endothelial paracrine dysfunction. Organization of uncomplicated SAM lesions could resemble certain types of fibromuscular dysplasia, suggesting that the genesis of such arterial lesions is related to vasospasm.
Recently human T-cell lymphotropic virus type I (HTLV-I) has been shown to be responsible for a kind of uveitis in southwestern Japan, where HTLV-I infection is highly endemic. To investigate further the association of HTLV-I with various ocular diseases, we studied HTLV-I seroprevalence in 1,350 patients in central Japan, where HTLV-I infection is not endemic. Of 1,350 patients with various ocular diseases, 40 (2.96%) were seropositive for the retrovirus. There was no statistically significant difference in HTLV-I seroprevalence among various ocular diseases. Four of 9 (44.4%) seropositive cases from southwestern Japan developed HTLV-I associated uveitis (HAU), whereas only 2 of 26 (7.7%) seropositive cases from central Japan developed HAU. The difference was statistically significant (p < 0.05). This suggests that the incidence of HAU could be influenced by environmental or hereditary factors. On the other hand, 3 of 7 (42.9%) patients with episcleritis showed HTLV-I infection.
In recent study, recurrence was seen in about 10% patients with node negative breast cancer during 10 years after operation. I evaluated prognostic factors including tumor diameter on the cut surface, histological infiltration diameter, histological malignancy, and expression of c-erbB-2 oncoprotein in 779 patients with node-negative breast cancer. The patient were operated from 1960 to 1972 at the Cancer Institute Hospital, Tokyo. The overall survival rate in this series was 88.6% at ten years. The survival rate at ten years for patients with tumor more than 21mm in size was 82.6%, and for those with tumor more than 11mm in filtrated size was 83.1%. On the other hand, marked fatty tissue infiltration, marked lymphatic vessel invasion, extensive histological invasion and numerous mitosis were associated with poor prognosis. The expression of c-erbB-2 oncoprotein correlated with recurrence within 5 years.