Hepatic retransplantation in children.
Explore the source record for details and available documents.
Actuarial Analysis↗
Biomedical subjects
M Inagaki
Publications and source records attributed to M Inagaki.
Antipyrine concentrations in liver and blood monitored by microdialysis of unrestrained conscious rats.
A newly developed microdialysis probe for measurement of drugs in unrestrained, conscious animals was used for quantitation of antipyrine in liver and blood of rats. Microdialysis probe were implanted in the liver and right jugular vein of rats; antipyrine was then administered at a dose of 50 mg/kg i.p. The concentration of antipyrine was determined in the fluid from the two probes and compared with measurement made on blood drawn from the left jugular vein. The elimination half lives in serum, blood dialysate and hepatic dialysate were 2.24 +/- 0.09, 2.06 +/- 0.31 and 2.10 +/- 0.32 hrs, respectively; there were not significantly different statistically. The concentration of Na+, K+ and Cl- in the hepatic dialysate was stable at least for up to 12 hrs in anesthetized rats. In unrestrained, conscious animals these electrolytes were stable in hepatic dialysate for at least 48 hrs. Therefore, the microprobe should be useful for analysis of drugs in extra cellular fluids of rats liver for up to 48 hrs. These studies suggest that this microdialysis technique by employing the newly developed probe will be useful in many studies on pharmacokinetics and drug metabolism in the organ.
Anesthesia↗
Effect of local cyanide perfusion on rat striatal extracellular dopamine and its metabolites as studied by in vivo brain microdialysis.
To investigate in vivo effects of energy failure on functions of dopaminergic neurons, we administered 0 (control), 0.2, 1 or 2 mM sodium cyanide (NaCN) dissolved in Ringer's solution for 60 min into the rat striatum through a brain microdialysis membrane. During NaCN perfusion, a transient and concentration-dependent increase in dopamine (DA) levels in the dialysate was observed. The maximum DA level during 2 mM NaCN perfusion was found to be 63-fold higher than the control levels. Leves of 3,4-dihydroxyphenylacetic acid and homovanillic acid were continuously lowered during and after NaCN perfusion. These data suggest that suppression of ATP production by NaCN induces an abrupt and remarkable increase in dopamine release from the nerve terminal in the striatum.
3,4-Dihydroxyphenylacetic Acid↗
The phosphorylation of kinesin regulates its binding to synaptic vesicles.
Membrane organella are transported bidirectionally in cells, and the axonal transport system has provided an ideal model system for studying this bidirectional transport. Kinesin and cytoplasmic dynein were identified as candidates for the motor molecules of fast axonal transport, which transport organella along microtubules anterogradely and retrogradely. However, the mechanism that controls this bidirectional transport is unknown. Our previous work revealed that kinesin in axons was associated abundantly with anterogradely transported membranous organella, most of which are believed to be precursors of synaptic vesicles and axonal plasma membranes, while the fractions bound to retrogradely transported ones were very small (Hirokawa, N., Sato-Yoshitake, R., Kobayashi, N., Pfister, K. K., Bloom, G. S., and Brady, S. T. (1991) J. Cell Biol. 114, 295-302). Here we demonstrated in vitro that the binding of kinesin to synaptic vesicles was concentration-dependent and saturable and could be released by high salt concentration. When kinesin was phosphorylated by cAMP-dependent protein kinase, its binding to symaptic vesicles was significantly reduced. By motility assay and by statistical analysis using electron microscopy, we further revealed that synaptic vesicles preincubated with phosphorylated kinesin associated less frequently with microtubules than synaptic vesicles preincubated with unphosphorylated kinesin. The phosphorylation of kinesin should therefore play an essential role in regulating the direction of fast axonal transport by inhibiting its binding to membrane organella, thus releasing it from membrane organella at nerve terminals.
Animals↗
Cell physiology of antisense TGF-beta oligomers in hepatoma cells.
Explore the source record for details and available documents.
Base Sequence↗
Requirement of phosphatidylinositol 4,5-bisphosphate for alpha-actinin function.
Inositol phospholipid turnover is enhanced during mitogenic stimulation of cells by growth factors and the breakdown of phosphatidylinositol 4,5-bisphosphate (PtdInsP2) may be important in triggering cell proliferation. PtdInsP2 also binds actin-binding proteins to regulate their activity, but it is not yet understood how this control is achieved. The protein alpha-actinin from striated muscle contains large amounts of endogenous PtdInsP2, whereas that from smooth muscle has only a little but will bind exogenously added PtdInsP2. In vitro alpha-actinin binds to F-actin and will crosslink actin filaments, increasing the viscosity of F-actin solutions. We report here that alpha-actinin from striated muscle is an endogenous PtdInsP2-bound protein and that the specific interaction between alpha-actinin and PtdInsP2 regulates the F-actin-gelating activity of alpha-actinin. Although the F-actin-gelating activity of alpha-actinin from smooth muscle is much reduced compared with that from striated muscle, exogenous PtdInsP2 can enhance the activity of smooth muscle alpha-actinin to the level seen in striated muscles. These results show that PtdInsP2 is present in striated muscle alpha-actinin and that it is necessary for alpha-actinin to realize its maximum gelating activity.
Actinin↗
Purification and characterization of smooth muscle myosin-associated phosphatase from chicken gizzards.
Myosin light chain phosphatase associated with smooth muscle myosin (MAPP) was isolated from chicken gizzard. The MAPP was tightly associated with myosin and was not dissociated from myosin under the physiological ionic conditions. The phosphatase was dissociated from myosin in the presence of high MgCl2, i.e. 80 mM MgCl2. The binding site of the enzyme on the myosin molecule was the subfragment-2 region, since the enzyme did bind to the myosin rod and heavy meromyosin but not to the subfragment-1 affinity column. MAPP was purified with a heparin-Sepharose 6B column, and two activity peaks were obtained, i.e. MAPP I and MAPP II. The major activity peak, MAPP I, was further purified to homogeneity by thiophosphorylated myosin light chain-Sepharose 4B column chromatography. MAPP I was a tetramer composed of four 34-kDa subunits. The enzyme preferentially dephosphorylated the beta-subunit of phosphorylase kinase and was strongly inhibited by the heat- and acid-stable protein phosphatase inhibitor-1, whereas it was partially inhibited by the inhibitor-2. The IC50 (concentration of inhibitor giving 50% inhibition) value for the inhibition of the enzyme by okadaic acid was 70 nM which was about eight times higher than skeletal muscle type-1 and 390 times higher than type-2 protein phosphatase. These results demonstrate that the MAPP I is a type-1-like protein phosphatase, although the properties are not the same as type-I phosphatase. The properties of the myosin-associated phosphatase were distinct from the phosphatases reported previously, although some properties were similar to smooth muscle phosphatase-IV. Therefore, it is concluded that MAPP I is a novel smooth muscle protein phosphatase. Since it strongly associated with smooth muscle myosin, it is likely that MAPP I is responsible for the dephosphorylation of smooth muscle myosin in situ.
Adenosine Triphosphate↗
Inositol phospholipid-induced suppression of F-actin-gelating activity of smooth muscle filamin.
Filamin, a high molecular weight actin-binding protein, cross-links actin filaments and produces a gel composed of F-actin. The effects of polyphosphoinositides on the gelating activity of smooth muscle filamin were examined by measuring the low shear viscosity of the F-actin solutions containing filamin incubated with phosphatidylinositol (PI), phosphatidylinositol 4-monophosphate (PIP), or phosphatidylinositol 4,5-bisphosphate (PIP2). Micelles of these inositol phospholipids bound to filamin inhibited the ability to form a gel of F-actin. The inhibiting activity of each phospholipid was in the following order, PIP2 greater than PIP greater than PI. The F-actin binding assay of filamin revealed that the inhibition of F-actin-gelation resulted in the loss of the F-actin-binding activity of filamin. Thus, polyphosphoinositides may play important roles in regulating the gelating activity of filamin.
Actins↗
Phosphorylation by actin kinase of the pointed end domain on the actin molecule.
Fragmin from plasmodium of Physarum polycephalum binds G-actin and severs F-actin in the presence of Ca2+ over 10(-6) M. The fragmin-actin complex consisting of fragmin and G-actin nucleates actin polymerization and caps the barbed (fast growing) end of F-actin, regardless of the concentrations of Ca2+, and the actin filaments are shortened. Actin kinase purified from plasmodium abolishes the nucleation and capping activities of the complex by phosphorylating actin of the fragmin-actin complex (Furuhashi, K., and Hatano, S. (1990) J. Cell. Biol. 111, 1081-1087). This inactivation of the complex leads to production of long actin filaments. We obtained evidence that Physarum actin is phosphorylated by actin kinase at Thr-201, and probably at Thr-202 and/or Thr-203, with 1 mol of phosphate distributed among them. This finding raises the possibility that the site of phosphorylation, Thr-201 to Thr-203, is positioned on the pointed (slow growing) end domain of the actin molecule, because growth of actin filaments from the fragmin-actin complex occurs only from the pointed end. These observations are consistent with a model of the three-dimensional structure of G-actin. Inactivation of the fragmen-actin complex may follow phosphorylation of the pointed end domain of actin.
Actins↗
Two different protein kinases act on a different time schedule as glial filament kinases during mitosis.
Glial fibrillary acidic protein (GFAP) is a component of glial filaments specific to astroglia. We now report the spatial and temporal distributions of four phosphorylated sites in the GFAP molecule during mitosis of astroglial cells, determined by antibodies which can distinguish phosphorylated epitopes from non-phosphorylated-epitopes. Immunofluorescence microscopy showed that the Ser8 residues in the entire cytoplasmic glial filament system are initially phosphorylated when the cells enter mitosis. In cytokinesis, the phosphoSer8 residues become dephosphorylated, whereas Thr7, Ser13 and Ser34 in glial filaments at the cleavage furrow become the preferred sites of phosphorylation. The cdc2 kinase purified from mitotic cells can phosphorylate GFAP at Ser8 but not at Thr7, Ser13 or Ser34, in vitro. These results suggest that cdc2 kinase acts as a glial filament kinase only at the G2-M phase transition while other glial filament kinases are probably activated at the cleavage furrow before final separation of the daughter cells.
Amino Acid Sequence↗
Brain oxygenation state: preparation of isolated perfused rat brain and near-infrared spectrophotometry.
The method of blood-free isolated perfused rat brain was described, of which EEG was within the normal range. The simultaneous measurement of heme a+a3 and copper in cytochrome oxidase could be performed under the various conditions such as graded hypoxia and seizure. The relationship between these two chromophores in the brain was same to that of isolated mitochondria.
Animals↗
Hepatic support by hepatocyte transplantation in congenitally metabolic diseased rats.
Nagase analbuminemic rats (NAR), which lack albumin synthesis in the liver, underwent intrasplenic hepatocyte transplantation (HCTx), and the long-term effects were studied using functional and morphological examinations. Hepatocytes were isolated from congenic F344 rats with collagenase infusion, and 1 x 10(7) cells were injected into the spleen of 3-month-old NAR (n = 10). Serum albumin increased with time, reaching 53.9 mg/dl 14 months after HCTx, which was equivalent to 2.1% (maximum 4%) of serum albumin in normal rats. On the other hand, untreated NAR showed persistently low serum albumin levels (0.99 +/- 0.23 mg/dl at 10 months). According to immunostaining with anti-rat albumin antibody at 16 months after HCTx, hepatocyte grafts occupied 27-41% of the spleen area and weighed 120-420 mg, which was equivalent to 0.8-2.9% of a whole liver. Our study demonstrated that grafted hepatocytes can grow in the spleen with the ability to synthesize albumin. HCTx in NAR is a new experimental system to monitor the function and survival of grafted heptocytes without sacrificing the animals by measuring serum albumin levels. Certain manipulations to facilitate the growth of grafted hepatocytes are necessary to achieve sufficient hepatic support in HCTx.
Animals↗
Six strains of human immunodeficiency virus type 1 isolated in Japan and their molecular phylogeny.
Five strains of human immunodeficiency virus type 1 (HIV-1) were isolated from five Japanese hemophilia patients. Two isolates, HIV-1[GUN-1] and HIV-1[GUN-2], were from brother patients with hemophilia B and the other three isolates, HIV-1[GUN-3], HIV-1[GUN-4], and HIV-1[GUN-5], were from hemophilia A patients. Another HIV-1 strain, HIV-1[GUN-6], was isolated from a Canadian male homosexual with AIDS. The restriction endonuclease cleavage maps of the proviral genomes of these six HIV-1 strains revealed that they were apparently different from each other. The phylogenetic trees constructed using restriction maps and nucleotide sequences were quite similar, indicating that phylogenetic analyses of Japanese HIV-1 isolates can be done using restriction maps of the proviruses. Phylogenetic analyses showed that they were more closely related to HIV-1s which had been reported to be isolated from homosexual patients in the United States than those isolated from African patients. In particular, GUN-1 and GUN-2 isolates were on the branch of a San Francisco isolate, ARV2, while GUN-5 and GUN-6 isolates were on the branch of HTLV-IIIB-related isolates.
AIDS-Related Complex↗
Relative hypoxia of the extremities in Fabry disease.
A purine degradation study, thermography and near infrared spectroscopy of the extremities were performed on 2 young males with Fabry disease and 2 healthy controls. Two-minute semi-ischemic forearm exercise caused a distinct increase in lactate in all subjects, but venous hypoxanthine and ammonia were greatly increased only in the Fabry patients, suggesting a relatively hypoxic state of the extremities. Limb thermograms of the patients revealed glove and stocking type disturbance at rest. Poor recovery of the skin temperature of the hands and forearms after exercise was observed in the patients, but the sharp increase in oxygenated hemoglobin after total ischemia was found to be normal or near infrared spectroscopy. Neurotropin showed an analgesic effect, i.e. a strong and selective heat-productive action on the painful lesions, and suppressed the hypoxanthine level after exercise in 1 patient. Although the pathophysiology of the pain in Fabry disease has not been clearly elucidated, a relatively hypoxic state with peripheral hypothermia might play an important role in triggering of a painful attack or chronic burning paresthesia.
Adolescent↗
Congenital caudal spinal atrophy: a case report.
An infant presented at birth with symmetrical flaccid paraparesis limited to lower legs and feet, and involving the proximal and distal muscle group. Limitation of the ankle joints was noticed. There were no sensory deficits to painful stimuli and no evidence of loss of sphincter control. Muscle CT revealed severe muscle atrophy in the pelvis and lower limbs, and electromyographic study of the bilateral hamstrings showed polyphasic giant potentials. Motor and sensory nerve conduction velocities were within normal limits, and the spinal MRI showed no structural abnormalities in the cord and the lower spine. These features suggest a congenital segmental abnormality at the anterior horn cell level in the lumbosacral spinal cord, which we propose to call "congenital caudal spinal atrophy".
Arthrogryposis↗
The results of reduced-size liver transplantation, including split livers, in patients with end-stage liver disease.
We initiated a policy of using RSLT in critically ill patients in June of 1988. Since that time we have performed 30 RSLTs in 29 patients, including 28 children and 1 adult. The mean age of the children was 27 months (range 1 month to 10 years) with 14 (52%) being 1 year of age or less. The mean weight was 11.3 kg (range 2-50 kg) with 20 being 10 kg or less. A total of 22 patients were in the intensive care unit at the time of RSLT including 9 who were intubated. Of the 30 RSLTs, 23 were performed as a primary transplant while 7 were retransplants. Indications for primary transplantation included biliary atresia (n = 11), fulminant hepatic failure (n = 5), neonatal hepatitis (n = 4) and others (n = 3). The RSLT was used in retransplantation for primary nonfunction (n = 2), hepatic artery thrombosis (n = 2), chronic rejection (n = 2), and herpetic hepatitis (n = 1). The size reductions included 18 left lobes, 7 left lateral segments, and 5 right lobes. This group includes the use of the split-liver technique, which was applied to 10 patients (5 livers). The median donor/recipient weight ratio for left lobe transplants was 2:1; left lateral segments was 7.3:1; and right lobes 1.6:1. One year actuarial patient and graft survivals were 68 and 65%, respectively, with a mean follow-up of 10.6 months. The number of children dying awaiting transplantation has been significantly reduced following the introduction of RSLD (3 of 115, 2.6% vs. 12 of 95, 13%; P less than 0.02).
Adult↗
[Evaluation of serological and biochemical diagnosis of candidemia].
In order to compare 4 serological and biochemical diagnostic tests, HA-test (Candida-HA-test), Cand-Tec, D-arabinitol detective test and Fungal Index (F.I.) were carried out in a total of 8 patients with candidemia, 6 were diagnosed to have systemic candidosis and 2 transient fungemia due to colonized catheters. Rabbits were given venous injections of 1.0 x 10(6) CFU (1 ml) of living Candida albicans type A to study the 4 diagnostic methods by sequential blood culture. Prior to clinical administration of antimycotics the diagnostic methods produced almost the same positive ratios. After administration of antimycotics, the HA-test became positive later than Cand-Tec or D-arabinitol because it detected antibodies in the serum, but its conversion to negative also tended to be slightly slower. Accordingly, the HA-test is considered to be useful for retrospective diagnosis of systemic candidosis. In Cand-Tec, D-arabinitol and F.I., the cases where reversion to normal was not achieved soon after therapy were intractable. In one case, the antigen values after therapy were four times as high as prior to treatment. To differentiate the two cases with transient fungemia from those with systemic candidosis HA- and D-arabinitol tests were considered to be superior to Cand-Tec and F.I. In the experiments with rabbits Cand-Tec was, in spite of its being positive in blood culture, always negative.
Adolescent↗
Cytoplasmic filaments in the endothelial cells of the sheathed capillary: an ultrastructural and immunocytochemical study in the pig spleen.
Cytoplasmic filaments of the endothelial cells of sheathed capillaries in the pig spleen were identified and their ultrastructure was studied. Two types of cytoplasmic filaments were found: intermediate filaments (diameter: 10 nm) which filled most of the interior of the cells, and thin filaments (diameter: 5 nm) which were located just beneath the cell membrane and filled the lateral cytoplasmic processes. In immunocytochemical preparations, the intermediate filaments were positive for vimentin and desmin, and were negative for keratin. Staining of the thin filaments with heavy meromyosin resulted in arrowhead formations. These observations suggest that the intermediate filaments maintain the cytoarchitecture, possibly protecting the cell from structural alterations induced by blood pressure changes. Concurrently, thin filaments may facilitate the passage of red blood cells and blood platelets through the interendothelial fenestrae of the sheathed endothelial cell to the reticular meshwork in the capillary sheath.
Animals↗