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K Sugimoto

Publications and source records attributed to K Sugimoto.

At least 109 records · Page 6Linked to original sources
PubMed2000

The effect of a Rho kinase inhibitor Y-27632 on superoxide production, aggregation and adhesion in human polymorphonuclear leukocytes.

We investigated the involvement of p160ROCK (a Rho-associated coiled coil-forming protein kinase), one of Rho kinases on superoxide anion production (O(2)(-) production), aggregation and adhesion of human polymorphonuclear leukocytes under physiological condition, using a selective p160ROCK inhibitor, (+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl)cyclohexanecarboxamide (Y-27632). Y-27632 inhibited the O(2)(-) production stimulated by phorbol-12-myristate-13-acetate (PMA) in a dose-dependent manner. Stauroprorine blocked the PMA-induced O(2)(-) production while wortmannin did not. Y-27632 also inhibited the O(2)(-) production by guanosine 5'-O-(3-thiotriphosphate) (GTP(gamma)S) 100 microM. N-formyl-Met-Leu-Phe (fMLP)-induced O(2)(-) production was not influenced by Y-27632, but was inhibited by wortmannin. The enhanced O(2)(-) production by Ca-ionophore A23817 and thapsigargin was not inhibited by Y-27632. Y-27632 did not change the basal intracellular Ca(2+) concentration nor its elevation stimulated by fMLP. Polymorphonuclear leukocytes aggregation induced by PMA was dose-dependently decreased by Y-27632 while their aggregation stimulated by fMLP was enhanced by the agent. Polymorphonuclear leukocytes adhesion induced by PMA or fMLP was not influenced by Y-27632.These results suggest that p160ROCK is involved in the PMA-induced O(2)(-) production and aggregation in human polymorphonuclear leukocytes. This kinase might locate in downstream of protein kinase C in polymorphonuclear leukocytes.

Adult↗
PubMed2000

Expression and subcellular localization of multifunctional calmodulin-dependent protein kinases-I, -II and -IV are altered in rat hippocampal CA1 neurons after induction of long-term potentiation.

Long-term potentiation (LTP) is considered to be associated with an increase in expression as well as activity of Ca(2+)/calmodulin-dependent protein kinases (CaMKs). LTP-induced and control hippocampal slices were studied by immunohistochemical and electronmicroscopic analyses using anti-CaMK-I, -II and -IV antibodies. All three kinases were demonstrated to increase their expression in CA1 neurons. CaMK-I was shown to mainly localize in the cytoplasm of the control and LTP-induced neurons, and a significant increase of immunoreactivity was observed in the latter neurons. A part of CaMK-I was found to translocate to the nuclei of LTP-induced hippocampal CA1 neurons. Direct evidence of the translocation of CaMK-II from cytoplasm to nuclei in LTP was demonstrated by immuno-electronmicroscopy. A significant increase in expression of CaMK-IV in the nuclei was also observed. Our data suggest that all the three CaMKs were actively involved in nuclear Ca(2+)-signaling in LTP.

Animals↗
PubMed2000

Quantitative ultrasonic tissue characterization can identify high-risk atherosclerotic alteration in human carotid arteries.

BACKGROUND: Recently, ultrasonic tissue characterization of the composition of plaques has been performed in a quantitative fashion on the basis of integrated backscatter (IBS) analysis, but most of those studies have used high-frequency ultrasound to obtain microscopic images. METHODS AND RESULTS: We performed B-mode measurement and IBS signal analysis with acoustic densitometry with a 7.5-MHz linear-array transducer in freshly excised human aortas (n=58) (normal, atheromatous, and fibrous tissue) obtained at autopsy. Atheromatous and fibrous tissue had a similar intima-media thickness (IMT), but the IBS value in atheromatous specimens was lower than that in fibrous specimens. We further applied this method to human carotid ultrasonography. The subjects were young (80 regions), middle aged with 1 or no coronary risk factors (low risk) (120 regions), middle aged with >/=2 coronary risk factors (high risk) (240 regions), or elderly (80 regions) or were patients with myocardial infarction (MI) with multivessel disease (90 regions). The IMT was similar in middle-aged, elderly, and MI subjects. In contrast, the IBS value was significantly higher in elderly subjects and lower in high-risk middle-aged and MI subjects compared with that in low-risk middle-aged subjects. The percent of regions diagnosed as atheromatous (IBS less than mean minus 2-SD value of IBS in young subjects) was 11% in low-risk middle-aged subjects, 29% in high-risk middle-aged subjects, and 63% in the MI group. CONCLUSIONS: In conjunction with conventional B-mode imaging, IBS analysis with carotid ultrasonography appeared to provide prognostic information to identify a high-risk group with systemic atherosclerosis, which could lead to coronary heart disease in individuals with early-stage disease.

Adult↗
PubMed2000

Use of echocardiography for predicting myocardial viability in patients with reperfused anterior wall myocardial infarction.

Dobutamine stress echocardiography (DSE), myocardial contrast echocardiography (MCE), and ultrasonic tissue characterization with integrated backscatter are useful methods for assessing myocardial viability in acute myocardial infarction. In this study, we compared the potential of 3 methods for predicting myocardial viability in 38 patients with reperfused anterior wall acute myocardial infarction. We performed MCE shortly after coronary reperfusion with an intracoronary injection of microbubbles. We recorded 2-dimensional integrated backscatter images at rest and, then, performed low-dose (10 microg/kg/min) DSE 3 days later. In integrated backscatter images, we placed the region of interest in the midwall of the myocardial segment to reconstruct the cyclic variation of myocardial integrated backscatter. The myocardial segment was judged viable when it showed active contraction 3 months later. Among 74 segments analyzed, 34 were judged viable. Presence of contractile response during DSE predicted segmental viability with 91% sensitivity and 78% specificity. Intense and homogenous contrast enhancement with MCE predicted viability with 82% sensitivity and 73% specificity. The presence of synchronous contraction of cyclic variation predicted myocardial viability with 79% sensitivity and 83% specificity. There were no differences in sensitivity and specificity among the 3 methods. Thus, MCE and ultrasonic tissue characterization can predict myocardial viability as accurately as DSE in patients with acute myocardial infarction. The logistics of the methods may determine clinical application.

Angioplasty, Balloon, Coronary↗
PubMed2000

Analysis of highly frequent allelic loss region on distal chromosome 12 in murine radiation-induced lymphomas.

Recent genetic studies of tumorigenesis have strongly suggested an existence of tumor suppressor gene(s) on murine chromosome 12 and human chromosome 14q32. We previously described that putative tumor suppressor gene(s) might reside between D12Mit53 and D12Mit233. We analyzed three genes, Tcl1, Yy1 and Tnfalphaip2, which had been mapped around the region, as the candidates in radiation lymphomagenesis of (BALB/c x MSM/Ms)F1 hybrid mice. The locus order and distances of the three genes and microsatellite loci were estimated as follows: [centromere] - Tcl1-(> or =0.085 cM)-D12Mit50-(0.085 cM)D12Mit132-(1.96 cM)D12Mit122-(0.085 cM)D12Mit53-(1.37 cM)-[D12Mit233,D12Mit279,Yy1]-(0.085 cM)-D12Mit181-(> or =0.17 cM)-Tnfalphaip2 - [telomere]. Allele losses at Tcl1, Yy1 genes and D12Mit233 were observed in 94(45%), 143(68%) and 147(70%) of 210 lymphomas, respectively. In semi-quantitative analysis of Yy1 mRNA levels by RT-PCR, kinetics of the yield of the Yy1-cDNA-specific PCR products showed almost the same profiles among thymic lymphomas with allelic loss at Yy1, lymphomas with both alleles retained and normal thymus. These results suggest that Tcl1, Yy1 and Tnfalphaip2 genes are not predominantly involved in radiation lymphomagenesis of mice. In further analysis of the common allelic loss region, we found new loci, Y152pR1 and Y184pR2, from YACs which located in the hot region between D12Mit53 and D12Mit233, and the highest frequency of allelic loss (71%) was observed at the Y184pR2 locus. The LOH patterns of individual lymphomas suggest that putative tumor suppressor gene(s) lies between Y152pR1 and Y184pR2.

Animals↗
PubMed2000

Inverse expression of Cdk4 and p16 in epithelial ovarian tumors.

OBJECTIVES: The aim of this study was to elucidate the expression and the correlation of two cell cycle regulators, cdk4 and its inhibitor p16, in a series of benign, borderline, and malignant ovarian tumors and to evaluate whether their alterations correlate with clinicopathologial parameters and patients' prognosis in epithelial ovarian carcinomas. METHODS: Immunohistochemical analysis using anti-cdk4 and anti-p16 antibodies was carried out for 103 paraffin sections of ovarian tumors, and Western blot analysis and cdk4 activity assay were performed in 26 fresh ovarian tumor samples. RESULTS: The results of immunohistochemistry showed that 60.61 and 69.70% of benign, 69.57 and 56.52% of borderline, and 74.47 and 40. 43% of malignant tumors expressed cdk4 and p16, respectively, demonstrating increased cdk4 and decreased p16 expression in ovarian carcinomas. A significant inverse relationship between cdk4 and p16 expression was found. The loss of p16 expression was more correlated with G(2) and G(3) tumors in contrast with G(1) tumors. No significant correlation was observed between cdk4 expression and clinicopathological parameters. Neither cdk4 nor p16 expression has significant effects on overall survival by the Kaplan-Meier method. When the combined phenotypes of the two proteins were analyzed, patients with cdk4-positive/p16-negative expression had a reduced overall survival than other phenotypes of cdk4/p16. CONCLUSIONS: These data suggest that inverse expression of cdk4 and p16 may be involved in the development and progression of epithelial ovarian carcinomas. The combined phenotypes of cdk4 and p16 proteins could provide a useful prognostic indicator for patients with epithelial ovarian carcinoma.

Adenocarcinoma↗
PubMed2000

Evaluation of 62Cu labeled diacetyl-bis(N4-methylthiosemicarbazone) as a hypoxic tissue tracer in patients with lung cancer.

62Cu labeled diacetyl-bis(N4-methylthiosemicarbazone) (62Cu-ATSM) has been proposed as a generator-produced, positron-emitting tracer for hypoxic tissue imaging. From basic studies, the retention mechanism of 62Cu-ATSM is considered to be closely related to cytosolic/microsomal bioreduction, a possible system for hypoxic bioreductive drug activation. In order to evaluate the characteristics of 62Cu-ATSM, PET studies were performed in 4 normal subjects and 6 patients with lung cancer. 62Cu-ATSM cleared rapidly from the blood with little lung uptake (0.43+/-0.09, uptake ratio; divided by the arterial input function) in normal subjects. Intense tumor uptake of 62Cu-ATSM was observed in all patients with lung cancer (3.00+/-1.50). A negative correlation was observed between blood flow and flow-normalized 62Cu-ATSM uptake in three of four patients. In contrast, 62Cu-ATSM uptake was not related to that of 18F-fluorodeoxyglucose. The negative correlation between blood flow and flow normalized 62Cu-ATSM uptake suggests an enhancement of retention of 62Cu-ATSM by low flow. 62Cu-ATSM is a promising PET tracer for tumor imaging, which might bring new information for chemotherapeutic treatment as well as radiotherapy of hypoxic tumors.

Adenocarcinoma↗
PubMed2000

A patient with undifferentiated carcinoma of gallbladder presenting with hemobilia.

Hemobilia is relatively rare among hemorrhages in the digestive tract, and hemobilia caused by tumors of the biliary tract is particularly rare. We treated a 74-year-old-man with undifferentiated carcinoma of the gallbladder presenting with hemobilia. During hospitalization for neurogenic bladder at the Department of Urology, he showed progressive anemia. Since hemorrhage in the digestive tract was suspected, endoscopy of the upper gastrointestinal tract was performed, and bleeding from the papilla of Vater was observed. On ultrasound examination, findings were indicative of cholecystic cancer, and hemorrhage from the cystic duct was found on percutaneous transhepatic cholangioscopy. On perioral cholecystoscopy, however, masses of coagulated blood were found only in the gallbladder. Abnormalities such as dense staining of tumors or extravasation were not found on angiography. The patient died of hepatic failure due to rapid invasion of the liver by the tumor, associated with biliary infection and disseminated intravascular coagulation. At autopsy, a nodal tumor was found in the gallbladder, and the cavity of the gallbladder was filled with coagulated masses of blood. Direct invasion of the tumor to the liver, diaphragm, and transverse colon was found. The histopathological diagnosis was undifferentiated carcinoma (pleomorphic large-cell type).

Aged↗
PubMed2000

A comparison of diabetic polyneuropathy in type II diabetic BBZDR/Wor rats and in type I diabetic BB/Wor rats.

AIMS/HYPOTHESIS: To examine the functional, metabolic and structural abnormalities in peripheral nerve in the spontaneously Type II (non-insulin-dependent) diabetic BBZDR/Wor rat and compare these data with those in the Type I (insulin-dependent) diabetic BB/Wor rat. METHODS: Animals were examined at 6 and 14 months of diabetes. Nerve conduction velocity was measured longitudinally. Nerve polyols were analysed using gas liquid chromatography and Na/K(+)-ATPase activity was measured enzymatically. Light and electron microscopic techniques were used for nerve morphometry. RESULTS: Diabetic BBZDR/Wor rats showed a slowly progressive nerve conduction defect that reached 17% (p < 0.01) at 14 months. There was a decrease in Na+/K(+)-ATPase of 35% (p < 0.05). Structurally, there were mild myelinated fibre atrophy (p < 0.05), mild or absent changes of the node of Ranvier, but significant (p < 0.001) segmental demyelination and Wallerian degeneration. These findings point to a more severe nerve conduction defect, severe myelinated fibre atrophy and profound nodal changes in Type I spontaneously diabetic BB/Wor rats maintained at the same hyperglycaemic concentrations. CONCLUSION/INTERPRETATION: We conclude that other factors, beside hyperglycaemia, are involved in the pathogenesis of the more severe Type I diabetic neuropathy which possibly involve insulin and C-peptide deficiencies.

Animals↗
PubMed2000

The effect of a hemofilter during extracorporeal circulation on hemodynamics in patients with SIRS.

OBJECTIVE: To evaluate the hypothesis that extracorporeal hemopurification with a hemofilter contributes to the stabilization of hemodynamics in patients with systemic inflammatory response syndrome (SIRS) due to a mechanism other than the removal of cytokines. DESIGN: Prospective study. SETTING: Intensive care unit (ICU) in a university hospital. PATIENTS: Seven critically ill patients who met criteria for SIRS with unstable hemodynamics requiring vasopressors after emergency surgery. INTERVENTIONS: Before initiation of continuous hemofiltration (CHF) extracorporeal circulation through the hemofilter (ECC) with a hollow-fiber polyacrylonitrile hemofilter was performed for 6 h. MEASUREMENTS AND RESULTS: Vital signs were monitored continuously and hemodynamics were evaluated intermittently. The blood level of endotoxin and the plasma levels of cytokines were measured at 0 and 6 h. Changes in plasma levels of cytokines passing through the hemofilter were evaluated at 3 h. A significant decrease of body temperature (P < 0.05 at 3 and 6 h vs 0 h), a significant elevation of mean arterial pressure (P < 0.05 at 0.5 h, P < 0.01 at 3 and 6 h vs 0 h), and a significant increase of urinary flow rate (P < 0.05 at 0 to 3 h vs -3 to 0 h) were observed with ECC. Neither the blood level of endotoxin nor the plasma levels of cytokines decreased. A significant increase of plasma IL-6 as it passed through the hemofilter was noted. CONCLUSIONS: The beneficial effects of hemopurification with a hemofilter on SIRS patients are possibly due to mechanisms other than the elimination of cytokines with ultrafiltration, diffusion, or adsorption.

Aged↗
PubMed2000

Detection of intracellular nitric oxide using a combination of aldehyde fixatives with 4,5-diaminofluorescein diacetate.

Using 4,5-diaminofluorescein diacetate (DAF-2DA), which was recently developed for the detection of intracellular nitric oxide (NO) in living cells, we examined the sensitivity of intracellular NO in cells treated with some fixatives. Cultured human umbilical vein endothelial cells loaded with DAF-2DA in the presence of 10(-6) M acetylcholine showed intense fluorescence when fixed in paraformaldehyde or glutaraldehyde, but no fluorescence could be detected after fixation in ethanol or acetone. Fluorescence generation depended on the combination of each aldehyde fixative with DAF-2, which is produced enzymatically from DAF-2DA within the cells. Subtracting the fluorescence intensity of non-activated controls from that of cells activated by acetylcholine indicated the NO produced in the stimulated cells, since the control cells that took up DAF-2DA also generated fluorescence when treated with aldehyde fixatives. Thus, detection of intracellular NO by combining aldehyde fixatives with DAF-2DA is useful for examining the functions of NO in cells both in situ and in vivo.

Acetone↗
PubMed2000

Interstitial cystitis and ileus in pediatric-onset systemic lupus erythematosus.

A girl aged 11 years presented with autoimmune hemolytic anemia with thrombocytopenia, and subsequently developed severe abdominal pain, vomiting, and pollakiuria. X-ray findings of her abdomen demonstrated paralytic ileus with intestinal wall thickening. Intravenous pyelography revealed bilateral hydroureter with mild hydronephrosis and contracted bladder. Pathological examination of her bladder revealed interstitial cystitis, with evidence of focal deposition of IgG and C3 in a granular pattern on small blood vessel walls. She was diagnosed as having systemic lupus erythematosus (SLE) associated with paralytic ileus and chronic interstitial cystitis. Although initiation of high-dose prednisolone therapy resulted in a gradual improvement in clinical symptoms, reducing the dosage of prednisolone caused a relapse. To our knowledge, the combination of paralytic ileus and chronic interstitial cystitis is quite uncommon in pediatric-onset SLE.

Child↗
PubMed2000

Morphologic changes of the ankle in children as assessed by radiography and arthrography.

Chronological changes in the morphology of the ankle, a joint that consists primarily of chondral components in children, were investigated by arthrography and plain radiography. Arthrography was performed in 57 ankles of 40 patients with normal ankles (aged from 2 months to 3 years, 4 months; mean, 1 year, 7 months), and plain radiography was performed on 183 joints of 126 patients with normal ankles (aged from 3 years, 6 months to 14 years, 5 months (mean, 7 years, 8 months). The angle of the distal tibial joint surface was then measured on each radiograph. Despite being evident at birth, valgus inclination in the ankle rapidly changed during the first and second years of life. Thereafter, change continued gradually and spontaneously, and the ankles were in the neutral position by 3 years of age. However, the morphology of the ankles did not change much after that time. Normal ankles show valgus inclination at birth, but this configuration is changed naturally over time, and the ankles are in the neutral or slightly varus position by the age of bone maturity.

Adolescent↗
PubMed2000

Interhemispheric subdural hematoma caused by a ruptured internal carotid artery aneurysm: case report.

BACKGROUND: Interhemispheric subdural hematoma (ISH) usually occurs after head trauma; nontraumatic ISH is extremely rare. CASE DESCRIPTION: The authors describe a 62-year-old male presenting with severe headache and ptosis on the left side. Computed tomography (CT) and magnetic resonance imaging disclosed a hematoma in the interhemispheric subdural space without subarachnoid hemorrhage. Cerebral angiography revealed an aneurysm arising from the left internal carotid-posterior communicating artery (IC-PC) junction. The patient underwent emergency clipping of the aneurysm and was discharged without neurological deficit. CONCLUSION: Ruptured aneurysms resulting in ISH without subarachnoid hemorrhage have been reported in only a few cases; this is the second case to describe the association of a ruptured IC-PC aneurysm with an ISH. The etiology of ISH formation due to ruptured aneurysms and the diagnosis are discussed.

Aneurysm, Ruptured↗
PubMed2000

Cloning and characterization of amphibian cold inducible RNA-binding protein.

Gene expression of cold inducible RNA-binding protein (CIRP) was examined in the frog. In Xenopus laevis, expression of CIRP (XCIRP) was observed in both brain and liver at 24 degrees C. Circadian expression of XCIRP was observed in brain. Expression of XCIRP in brain was induced by cold treatment and gradually decreased to the control level at 24 degrees C, but no significant changes were observed in liver. Employing the sequence of murine CIRP, bullfrog (Rana catesbeiana) CIRP gene was cloned. The bullfrog CIRP gene, designated BFCIRP, was 706 bp in length and encoded a putative protein of 164 amino acid residues. The deduced protein contained one consensus sequence of RNA-binding domain (CS-RBD) and a glycine rich domain (GRD). The amino acid sequence of BFCIRP was 78.4% identical to XCIRP. Expression of BFCIRP in brain was stronger in winter than that in summer. These findings suggest that BFCIRP expression in brain may link to hibernation.

Amino Acid Sequence↗