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K Ueki

Publications and source records attributed to K Ueki.

At least 19 recordsLinked to original sources
PubMed1992

Sequential activation of MAP kinase activator, MAP kinases, and S6 peptide kinase in intact rat liver following insulin injection.

An insulin-stimulated phosphorylation cascade was examined in rat liver after insulin injection via a portal vein by the use of immune complex kinase assays specific to the mitogen-activated protein (MAP) kinase and S6 kinase II homologue (rsk) kinase. We have prepared an antibody against the peptide consisting of a carboxyl-terminal portion of the extracellular signal-regulated kinase 1 (alpha C92), one of the MAP kinases, and an antibody against the peptide consisting of the carboxyl terminus of the mouse S6 kinase II homologue (alpha rsk(m)C). In alpha C92 immune complex assay, maximal activation of rat liver MAP kinases (approximately 4.3-fold) were observed 4.5 min after insulin injection. We also observed an insulin-stimulated MAP kinase activity (approximately 3-fold) in liver extracts from insulin-treated rat in fractions eluted from phenyl-Sepharose with 30-50% ethylene glycol. Kinase assay in myelin basic protein (MBP)-containing gel after sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by denaturation with 6 M guanidine HCl, and renaturation revealed that insulin injection stimulated the kinase activity of the 42- and 44-kDa proteins, which corresponded to the two distinct MAP kinases. In alpha rsk(m)C immune complex assay, maximal stimulation (approximately 5-fold) of the S6 peptide (Arg-Arg-Leu-Ser-Ser-Leu-Arg-Ala) kinase activity was observed 7.5 min after insulin injection. In addition, MAP kinases purified from insulin-treated rat liver were able to activate S6 peptide kinase activity in vitro in alpha rsk(m)C immunoprecipitates from untreated rat liver, accompanied by the appearance of several phosphorylated bands including a major band at 88 kDa. We also examined whether insulin injection stimulates the MAP kinase activator (Ahn, N. G., Seger, R., Bratlien, R. L., Diltz, C. D., Tonks, N. K., and Krebs, E. G. (1991) J. Biol. Chem. 266, 4220-4227) in rat liver. Using recombinant Xenopus MAP kinase, fractions of Q-Sepharose eluted early in the NaCl gradient were found to have MAP kinase activator activity accompanied by the phosphorylation of 42-kDa recombinant Xenopus MAP kinase. From these data, we demonstrate three tiers of a cascade composed of the MAP kinase activator, MAP kinases, and an S6 peptide kinase activity in rat liver under physiological conditions in the intact animal.

Adenosine Triphosphate↗
PubMed1992

Biphasic activation of two mitogen-activated protein kinases during the cell cycle in mammalian cells.

We studied mitogen-activated protein kinase (MAPK) activities during the cell cycle of Chinese hamster ovary (CHO) cells using site-specific antibodies against extracellular signal-regulated kinase-1, a 44-kDa MAPK (Boulton, T.G., Yancopoulos, G.D., Gregory, J.S., Slauer, C., Moomaw, C., Hsu, J., and Cobb, M.H. (1990) Science 249, 64-67). These antibodies detected two distinct MAPKs (44- and 42-kDa MAPKs) in CHO cells. CHO cells were arrested at metaphase in the M phase by treatment with nocodazole, and activities of MAPKs were analyzed at specific time points after release from arrest. Immune complex kinase assay and renaturation and phosphorylation assay in substrate-containing gel revealed that both 44- and 42-kDa MAPKs had activities in the G1 through S and G2/M phases and were activated biphasically, in the G1 phase and around the M phase. MAPKs were inactivated in metaphase-arrested cells. The amount of MAPKs did not change significantly in the cell cycle. In the G1, S, and G2/M phases, MAPKs were phosphorylated on both tyrosine and threonine residues and dephosphorylated in metaphase-arrested cells. Our data suggest that MAPKs may play some role in the cell cycle other than G0/G1 transition.

Amino Acid Sequence↗
PubMed1992

Structure and expression of two isoforms of the murine calmodulin-dependent protein phosphatase regulatory subunit (calcineurin B).

Murine cDNAs representing distinct genes for the regulatory subunits of calmodulin-dependent protein phosphatase (CaM-PrP) were cloned from a testis library, using probes prepared by PCR amplification of brain and testis mRNA. The cDNA sequence of the brain-specific isoform (beta 1) encodes a 170 amino acid protein (M(r) approximately 19.3 kDa), whereas that for the testis isoform (beta 2) contains 179 residues (M(r) approximately 20.7 kDa); these two sequences show approximately 80% amino acid identity. An oligonucleotide probe for the brain isoform hybridized to a single mRNA of 3.6 kilobases (kb) in many tissues, whereas using the beta 2 probe, two mRNAs of 1.8 and 0.8 kb were detected only in testis. The mRNA for the testis-specific isoform increases markedly during development, its pattern being virtually identical to that of mRNA for a testicular form of the catalytic subunit (alpha 3). These data are consistent with the biological co-regulation of catalytic and regulatory subunits of a testis-specific isoenzyme during germ cell maturation.

Amino Acid Sequence↗
PubMed1992

Immunologically induced coronary artery stenosis in allografts after heart and heart-lung transplantation in rats.

The role of the lung in suppressing immunologically induced coronary artery stenosis after heterotopic allograft transplantation was studied in rats. Thirty-nine recipients were divided into two groups: untreated and treated. The untreated group was divided into two subgroups--the heart allograft TH group and the heart-lung allograft THL group. The treated group was divided further into four subgroups depending on when the graft was harvested, after 30 days or 60 days (T30-H and T30-HL group, and T60-H, T60-HL, respectively). Rejection was assessed by Lurie's classification. The percent of intraluminal stenosis (PIS) was determined by planimetry. All treated animals received cyclosporin A 10 mg/kg/day intramuscularly for 20 days. In the untreated group, heart-lung allograft survival was longer than heart allograft survival. In the treated group, all grafts were still beating when the animals were killed. The rejection grade score in the T30-H and T30-HL groups were lower than those in the T60-H or T60-HL groups. The PIS in the THL group was slightly lower than that in the TH group. However the PIS increased over time in both the TH and THL groups. This study demonstrates that the lung suppresses but does not abolish immunologically induced coronary atherosclerosis-like occlusive lesions after cardiac transplantation.

Animals↗
PubMed1992

[Inhibition of neovascularization and tumor growth by dexamethasone].

It has been proposed that angiogenesis inhibitors should be used for the treatment of diseases accompanied by an uncontrolled angiogenic response, particularly such disease occurring during progressive growth of solid tumors. In this study, the antiangiogenic effect of dexamethasone (DEX) was studied in a system using chorioallantoic membranes (CAM) of fertilized eggs and rabbit corneas. First, DEX was examined for its effect on embryonic angiogenesis using 4, 5 day old CAMs of chick embryos. After the shell and shell membrane was removed, an EV pellet with or without DEX was placed within a silicon ring. Two days later, the antiangiogenic response was evaluated by measuring the avascular zone of the CAM beneath the pellet. When the CAM showed an avascular zone of 3 mm or more in diameter, the response was scored as positive. DEX showed potent antiangiogenic activity and produced an avascular zone in 100% of CAMs at the highest dose tested. (250 ng/egg). Next, inhibitory effect of vascularization and tumor growth by local implant of DEX was observed in a rabbit cornea assay. An intra-corneal pocket extending to within 1 mm of the limbus was used to house a 1-mm3 piece of glioma. In the treatment group, DEX-containing EV pellet was inserted between the limbus and glioma. Ten days after the implantation of glioma and EV pellet, vascular response and tumor growth was evaluated. For morphologic studies, the excised corneas were fixed with formaldehyde fixative and sectioned for light microscopy.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

[Studies of human bone marrow stromal cells--effects of antimetabolites on the growing dynamics of human bone marrow cells and their support of hemopoietic cells].

The effects of antimetabolites on the growing dynamics of human bone marrow stromal cells and their support of hemopoietic cells were tested by using a modified version of Dexter's culture system. Cytosine arabinoside (ara-C) was found to suppress neither the growing dynamics nor the supportability. On the other hand, methotrexate (MTX) suppressed the supportiveness, even though it hardly suppressed the growing dynamics. The recognition of injury to marrow cells could be of potential importance in cancer chemotherapy. Our in vitro evidence may provide clinical insights for cancer chemotherapy including prolonged marrow suppression or pretreatment of bone marrow transplantation.

Adult↗
PubMed1992

[Pharmacokinetics and toxicological study on the intraperitoneal administration of cisplatin and etoposide in gynecological malignancies].

We administered cisplatin and etoposide into the peritoneal cavity of 13 postoperative patients with gynecological malignancies, and studied the pharmacokinetics and toxicity in the combination of both drugs. Cisplatin 100 mg/body and etoposide 200 mg-400 mg/body were mixed together in 500 ml or 1,500 ml of normal saline and administered intraperitoneally on the day of operation and two or three weeks later. The peritoneal peak level of free cisplatin, diluted with 500 ml, was about two times higher than that, diluted with 1,500 ml. However, there was no difference in the peritoneal and plasma AUC. The peritoneal level and AUC of etoposide, diluted with 500 ml, was about two times higher than that, diluted with 1,500 ml. Among the groups of 1,500 ml, peritoneal and plasma levels and AUC were almost proportional to the doses. Nausea and vomiting were experienced in all patients. With the increase of etoposide, more marrow suppression was observed. However, we encountered no other significant side effects. In conclusion, intraperitoneal administration of cisplatin and etoposide in this setting can be used safely with minimum side effects, and the dilution of 1,500 ml seems to be better.

Adult↗
PubMed1991

Insulin and 12-O-tetradecanoylphorbol-13-acetate activation of two immunologically distinct myelin basic protein/microtubule-associated protein 2 (MBP/MAP2) kinases via de novo phosphorylation of threonine and tyrosine residues.

Two site-specific antibodies have been prepared by immunizing rabbits with chemically synthesized peptides derived from the partial cDNA-predicted amino acid sequence of extracellular signal-regulated kinase 1 (ERK1), which has been proposed to encode the microtubule-associated protein 2 (MAP2) kinase (Boulton, T. G., Yancopoulos, G. D., Gregory, J. S., Slauer, C., Moomaw, C., Hsu, J., and Cobb, M. H. (1990) Science 249, 64-67). With immunoprecipitation in the presence of sodium dodecyl sulfate (SDS) and Western blotting, an antibody to the peptide containing triple tyrosine residues (alpha Y91) resembling one of the insulin receptor autophosphorylation sites specifically recognized 42- and 44-kDa proteins. On the other hand, an antibody to the peptide corresponding to the COOH terminus portions (alpha C92) of the ERK1 cDNA gene product recognized the 44-kDa protein much more efficiently than the 42-kDa protein. With immunoprecipitation in the absence of SDS, alpha Y91 could barely recognize these two proteins and alpha C92 recognized the 44-kDa protein but failed to recognize the 42-kDa protein. Kinase assays in myelin basic protein (MBP)-containing gel, after SDS-polyacrylamide gel electrophoresis, revealed that insulin or 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated MBP kinase activity in alpha Y91 immunoprecipitates comigrated at molecular mass 42 and 44 kDa. On the other hand, the stimulated MBP kinase activity in alpha C92 immunoprecipitates comigrated only at molecular mass 44 kDa. Insulin stimulated the MBP kinase activity in gels and phosphorylation of these two proteins by greater than 10-fold with a maximal level at 5 min. Insulin and TPA rapidly stimulate the phosphorylation of the 42- and 44-kDa proteins via de novo threonine and tyrosine phosphorylation. Tryptic phosphopeptide mapping analysis of the 42- and 44-kDa proteins, respectively, revealed a single major phosphopeptide containing phosphothreonine and phosphotyrosine, which was common to both insulin- and TPA-stimulated phosphoproteins. Protein phosphatase 2A treatment of these two phosphoproteins caused a complete loss of kinase activity with selective dephosphorylation of phosphothreonine. These data strongly suggest that these two proteins are highly related to the mitogen-activated protein (MAP) kinase with an apparent molecular mass of 42 kDa (Ray, L. B., and Sturgill, T. W. (1988) Proc. Natl. Acad. Sci. U.S.A. 85, 3753-3757) and that these two immunologically similar but distinct MBP/MAP2 kinases may represent isozymic forms of MBP/MAP2 kinases. These data also demonstrate that insulin and TPA activate MBP/MAP2 kinase activity by de novo phosphorylation of threonine and tyrosine residues via a very similar pathway.

Amino Acid Sequence↗
PubMed1991

Behavioral deficits induced by local injection of bicuculline and muscimol into the primate motor and premotor cortex.

1. The role of intracortical GABAergic inhibition in the performance of hand movements was studied in macaque monkeys while they performed two behavioral tasks: a raisin pick-up test and a visual reaction-time task. A gamma-aminobutyric acid (GABA) agonist, muscimol (MUS; 1-5 microgram), and an antagonist, bicuculline methiodide (BMI, 1-10 micrograms), were injected at various sites in the precentral motor cortex (MC), at which single-unit activity was related to the manual aspects of the performance of the reaction-time task. 2. Manual dexterity in the raisin pick-up task was severely disturbed by injections of either MUS or BMI into the hand MC. The effect was less severe after injections into the postarcuate premotor cortex (PM). 3. Performance of the reaction-time task was unstable after injection of BMI. The instability was caused by increased electromyogram (EMG) activity and by cocontractions of agonistic and antagonistic muscles of the arm during the pressing or release of the lever. 4. Reaction time was increased by injection of MUS, although the effect was temporary and decayed within 60 min. These deficits were consistent with the time course of the decrease in the total amount of EMG activity of hand muscles related to the task. As in the case of the raisin pick-up task, performance deficits were greater when MUS and BMI were injected into the hand MC and smaller when they were injected into the PM. 5. After injection of BMI, the animals gradually began to display muscle activity in response to a green warning signal that did not require a behavioral response. The muscle activity accelerated to spontaneous muscle twitches without any external stimulus, and the animals were unable to continue the task. These BMI-induced twitches were eliminated by injection of barbiturate. 6. Appropriate levels of GABAergic inhibition in the MC appear, therefore, to be important for the regulation of spatiotemporally organized ensembles of muscle activity, in particular for reciprocal contraction at the task-related joints.

Animals↗
PubMed1991

Three cases of multiple myeloma developing into melphalan-related chronic myelomonocytic leukemia.

From 1980 to 1987, three cases of chronic myelomonocytic leukemia (CMML) were encountered among 68 cases of multiple myeloma who survived more than three years from the diagnosis. The incidence (4.8%) of secondary myelodysplastic syndrome (MDS) is almost identical to previous reports, but case reports of chronic myelomonocytic leukemia were rare. In Japan, there are few reports of multiple myeloma patients who later developed secondary MDS or acute myelogenous leukemia (AML). In our cases, none of the 31 patients treated with cyclophosphamide developed secondary MDS, while three of 37 patients treated with melphalan developed CMML. This difference is not statistically significant.

Aged↗
PubMed1990

Intracranial hemorrhage associated with nontraumatic disseminated intravascular coagulation--report of four cases.

The authors report four cases of intracranial hemorrhage associated with nontraumatic disseminated intravascular coagulation (DIC). Two cases demonstrated a sudden onset of intracerebral hemorrhage. The other two showed chronic subdural hematoma initially, followed by acute multiple intracranial hemorrhages or general hemorrhagic diathesis. The underlying disorders were glioblastoma multiforme, thoracoabdominal aortic aneurysm, acute promyelocytic leukemia, and stomach cancer associated with disseminated carcinomatosis of the bone marrow. All patients died eventually. When the underlying disorder has a rare incidence of DIC as in glioblastoma multiforme or thoracoabdominal aortic aneurysm, the possibility of DIC and the need for immediate initiation of replacement therapy should be recognized, although the mortality is very high because the underlying disorder cannot be eliminated quickly. When the underlying disorder has a high incidence of DIC as in acute promyelocytic leukemia or disseminated carcinomatosis of the bone marrow, it is mandatory to start replacement therapy and treatment for the underlying disorder simultaneously. DIC can be controlled when the treatment for the underlying disorder is effective.

Adult↗
PubMed1990

[A sporadic case of protein C deficiency].

A congenital deficiency of protein C (PC) is reported in a 42-year-old male, suffering from his first spontaneous episode of deep venous thrombosis in the left lower limb. The only defect found in laboratory assays for hemostasis and hepatic function was half normal level of PC, measured by both immunological and functional assays. To confirm congenital PC deficiency, the functional activity levels of PC were compared with those of other vitamin K-dependent factors during stabilized anticoagulant therapy under stable conditions. Although the patient's father had a history of a cerebral vascular accident, his PC level was found to be within normal levels. The patient's mother, free from thromboembolic events, also had a normal PC level. So the patient seemed to be a sporadic case. However, the patient's 14-year-old son, who has been asymptomatic to this time, has the same PC deficiency state.

Adult↗
PubMed1990

[Clinical diagnosis of gliomatosis cerebri by radioimages].

Gliomatosis cerebri (GC) is a rare clinical entity characterized by diffuse and infiltrative overgrowth of the tumor cells. Most of the previously reported cases of GC were autopsy cases because the clinical diagnosis of GC has been difficult. The authors report four cases diagnosed clinically as GC. Cases 1 and 2 are females aged 19 and 69. Cases 3 and 4 are males aged 47 and 50. In the first three cases, CT findings were almost normal. MRI study, especially on its T2 weighted image (T2W1), clearly demonstrated the wide extent of the infiltration of the tumor cells along the white matter. The last case occurred in the pre-MRI era, but contrast enhanced CT showed a bilateral periventricular high density area accompanied by diffuse low density white matter. Three of them underwent echo-guided needle biopsy, and one underwent partial excision of the lesion. Histological diagnosis was glioblastoma in Cases 1 and 4, and anaplastic astrocytoma in Cases 2 and 3. Difficulty in the clinical diagnosis of GC has been based on the fact that traditional imaging studies, including CT, can not clearly show the extent of tumor cell infiltration. MRI study is a very sensitive imaging technique which can easily demonstrate the area infiltrated by glioma cells. So we may be able to make clinical diagnosis of GC, coupling the data from MRI study and brain biopsy. The authors expect that accumulation of clinical experiences of GC may give useful information for the investigation of "invasion", which is one of the major problems in the treatment of malignant gliomas.

Adult↗
PubMed1990

[A case of round atelectasis].

A case of round atelectasis was reported. The roentgenographic features of round atelectasis are "comet tail sign" and localized pleural thickening. Round atelectasis appears as a mass like lesion that often mimics a pulmonary neoplasm. Recognition of this entity will help to prevent unnecessary procedures such as thoracotomy and pulmonary resection.

Bronchography↗