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K Sugimoto

Publications and source records attributed to K Sugimoto.

At least 433 records · Page 24Linked to original sources
PubMed1992

[New puncture technique for TIPSS (transjugular intrahepatic portosystemic stent shunt)].

To establish a safer puncture method for TIPSS (Transjugular Intrahepatic Portosystemic Stent Shunt), we developed a new percutaneous puncture technique to penetrate portal and hepatic vein trans-hepatically under ultrasonography (US technique). Experimentally we compared this technique with conventional transjugular technique puncturing portal vein through hepatic vein using Ross needle (Ross Needle technique). Success rate is 100% in US technique and 50% in Ross needle technique. Seven complication including intraperitoneal bleeding occurred in Ross needle technique, but no complication in US technique. Conclusively, US technique is a safer and more reliable method than that using Ross needle in the puncture method for TIPSS.

Animals↗
PubMed1992

Frequent mutations in the p53 gene in human myeloid leukemia cell lines.

The p53 gene is currently considered to function as a tumor-suppressor gene in various human malignancies. In hematologic malignancies, alterations in the p53 gene have been shown in some human leukemias and lymphomas. Although mutations in the p53 gene are infrequent in acute myelogenous leukemia (AML) patients, we show in this report that alterations in the p53 gene are frequent in myeloid leukemia cell lines. We studied alterations of the p53 gene in nine human myeloid leukemia cell lines by reverse transcriptase-polymerase chain reaction (RT-PCR), single-strand conformation polymorphism (SSCP) analysis, and direct sequencing. Expression of the p53 gene was not detected at all by RT-PCR in two of the nine cell lines. In these two cell lines, Southern blot analysis showed gross rearrangements and deletions in both of the p53 alleles. Six of the nine cell lines were found to express only mutant p53 mRNA by RT-PCR/SSCP analysis and direct sequencing, and wild-type p53 mRNA was not detected. Two of the mutant p53 mRNAs were shown to be products of abnormal splicing events induced by intronic point mutations. Taken together, eight of nine human myeloid leukemia cell lines expressed no or an undetectable amount of wild-type p53 mRNA. Three of the eight cell lines were growth factor-dependent. Our results suggest that inactivation of the p53 gene may be a common feature in myeloid leukemia cell lines and may play an important role in the establishment of these cell lines.

Base Sequence↗
PubMed1992

A partial defect in technetium-99m pyrophosphate image suggesting cardiac rupture following acute myocardial infarction.

We present the case of a 70-year-old woman with acute myocardial infarction who died of cardiac rupture on the 2nd hospital day. Dual isotope single photon emission computed tomography (SPECT) using thallium-201 chloride and technetium-99m pyrophosphate (PYP) performed on the 2nd hospital day showed a large perfusion defect in the anteroseptal wall on 201Tl image and a increased accumulation on 99mTc-PYP image in the anterior area consistent with a partial defect. Autopsy performed 1 h after death revealed a tear in the left ventricular anterior wall consistent with the defect on the 99mTc-PYP image. We propose that the finding of a partial defect in 99mTc-PYP is an interesting finding which may be associated with cardiac rupture following acute myocardial infarction.

Aged↗
PubMed1992

Production of a negative regulator of IL-3 by bone marrow cells in response to the supernatant of IL-3-producing STIL-3 leukemia cells.

When spleen cells of mice grafted with STIL-3 C5 cells, a leukemic T-cell line producing IL-3, are cultured in vitro, a high IL-3 activity is detectable in the culture supernatant. However, when bone marrow cells of the same grafted mice are cultured under similar conditions, hardly any IL-3 activity is detectable. To elucidate the mechanism of this difference, we examined whether the bone marrow cells either suppress IL-3 production by STIL-3 C5 cells or produce an IL-3 inhibitor. When STIL-3 C5 cells were cultured in the presence of normal bone marrow cells, the culture supernatant showed a significantly reduced IL-3 activity as assessed by growth stimulatory effects on IL-3-dependent DA-1 cells and mast cells. The conditioned medium (CM) did not inhibit the growth of IL-3-independent cell lines. Heat treatment of the CM resulted in a recovery of the IL-3 activity, indicating that the effect was mediated by a heat-labile inhibitor rather than by suppression of IL-3 production. CM of bone marrow cells alone did not inhibit the IL-3 activity. The inhibitor was produced by a stem cell-enriched fraction of the bone marrow, and not by fractions of T cells, granulocytes, or adherent cells including macrophages. Stimulation of the stem cell-enriched fraction of bone marrow with STIL-3 C5-CM also induced the production of the IL-3 inhibitor, which was recovered in a MW 50-100 kD fraction after ultrafiltration. These results suggest a possible presence of a feedback mechanism against the IL-3 effect on hemopoietic stem cells and progenitors in the bone marrow.

Animals↗
PubMed1992

Criterion validity of the cross-cultural cognitive examination in Japan.

Criterion validity of a two-stage Cross-Cultural Cognitive Examination (CCCE) designed for epidemiologic use was evaluated in Japanese subjects by comparison with a physician's DSM-III-R diagnosis of dementia and the Hasegawa Dementia Rating Scale (the standard Japanese instrument similar to the Mini-Mental State Exam). We report on 188 subjects tested in three locations in Japan: Tokyo area, Ise, and Osaka. Subjects ranged in age (50-93 years) and education (1-22 years) and included neurology outpatients, community volunteers, and inpatients. The CCCE was 97.4% specific for dementia, with sensitivity of 88%. The correlation with the Hasegawa scale was significant (r(175) = .8230, p less than .0001). Diagnosis using the CCCE showed good validity when compared with Japanese criteria for dementia. If the instrument could be shown to be reliable and more "culture fair" than the currently available tests, it may be useful in cross-cultural epidemiologic studies of dementia.

Aged↗
PubMed1992

Anti-helix-loop-helix domain antibodies: discovery of autoantibodies that inhibit DNA binding activity of human centromere protein B (CENP-B).

Centromere protein B (CENP-B) is one of the centromere DNA binding proteins constituting centromeric heterochromatin of human chromosomes. This protein was originally identified as the target antigen in autoimmune disease patients (often with scleroderma). In this study, we cloned a human CENP-B cDNA which was longer than the previously isolated one and expressed functional recombinant CENP-B in Escherichia coli. The DNA binding domain was finely located within the N-terminal 134-amino-acid residues covering a predicted helix-loop-helix (HLH) structure, by using a set of recombinant products with stepwise deletions from the C-terminus. From the analysis of their reactivity to anti-centromere sera from autoimmune disease patients, four epitopes were mapped on CENP-B antigen. In addition to two epitopes at the C-terminus, two were found on the HLH region at the N-terminus. In the analysis of the interaction between the antigen and autoantibodies, we found that the DNA binding activity of CENP-B was distorted by the attack of the anti-HLH domain antibodies in in vitro binding reactions. Our results suggest that the direct inhibition of the DNA binding activity by the autoantibodies might be involved in patients' autoimmune reactions in vivo.

Amino Acid Sequence↗
PubMed1992

Pharmacokinetics and pharmacodynamics of benazepril in hypertensive patients with normal and impaired renal function.

The pharmacokinetics and pharmacodynamics of benazepril, an angiotensin converting enzyme (ACE) inhibitor, were investigated after administration of a single oral 5-mg dose and 7 more doses on consecutive days to hypertensive patients with normal renal function (NRF) and those with impaired renal function (IRF). The antihypertensive effect of benazepril was observed as early as 30 min after a single dose, and those effects during consecutive dosing were also sustained for 24 h with a lesser diurnal variation in blood pressure (BP). The time to peak (Tmax) and the apparent elimination half-life (t1/2) for benazepril were 0.6-0.7 h and 0.4-0.8 h, respectively. Tmax for its diacid was 1.5-2.4 h in both groups. The area under the plasma concentration-time curve to 24 h (AUC0-24h) for the diacid was significantly greater in the IRF group than in the NRF group. After consecutive dosing of benazepril, AUC0-24h and plasma peak level (Cmax) were significantly increased in the IRF group. Serum ACE activity was markedly suppressed for 24 h after administration, and the inhibition was closely related to plasma diacid levels. A significant inverse correlation was observed between creatinine clearance and the AUC for the diacid. These results suggest that benazepril is rapidly bioactivated to diacid and exhibits rapid onset and long-lasting antihypertensive effects. Dosage reduction might be required to minimize unnecessary drug accumulation in patients with severe IRF.

Administration, Oral↗
PubMed1992

Cyclin-B homologs in Saccharomyces cerevisiae function in S phase and in G2.

We have cloned four cyclin-B homologs from Saccharomyces cerevisiae, CLB1-CLB4, using the polymerase chain reaction and low stringency hybridization approaches. These genes form two classes based on sequence relatedness: CLB1 and CLB2 show highest homology to the Schizosaccharomyces pombe cyclin-B homolog cdc13 involved in the initiation of mitosis, whereas CLB3 and CLB4 are more highly related to the S. pombe cyclin-B homolog cig1, which appears to play a role in G1 or S phase. CLB1 and CLB2 mRNA levels peak late in the cell cycle, whereas CLB3 and CLB4 are expressed earlier in the cell cycle but peak later than the G1-specific cyclin, CLN1. Analysis of null mutations suggested that the CLB genes exhibit some degree of redundancy, but clb1,2 and clb2,3 cells were inviable. Using clb1,2,3,4 cells rescued by conditional overproduction of CLB1, we showed that the CLB genes perform an essential role at the G2/M-phase transition, and also a role in S phase. CLB genes also appear to share a role in the assembly and maintenance of the mitotic spindle. Taken together, these analyses suggest that CLB1 and CLB2 are crucial for mitotic induction, whereas CLB3 and CLB4 might participate additionally in DNA replication and spindle assembly.

Amino Acid Sequence↗
PubMed1992

The clinical expression in anticentromere antibody-positive patients is not specified by the epitope recognition of CENP-B antigen.

Centromere protein B (CENP-B), which is an alphoid DNA binding protein, is the target antigen in autoimmune disease patients (often with scleroderma). From our previous analysis of the reactivity of anticentromere sera, four independent epitopes were identified on recombinant CENP-B. The anticentromere sera displayed heterogeneity in their patterns of reactivity to the four epitopes. We have investigated to what extent this heterogeneity of the target autoepitope on CENP-B accounts for the clinical diversity of anticentromere antibody (ACA)-positive patients. A major autoepitope, epitope I, was recognized by all 40 ACA-positive sera; however, the other three epitopes were recognized differently from case to case. We could not find any significant correlation between the reactivity to CENP-B autoepitopes and the clinical presentation of ACA-positive patients. There was considerable clinical diversity, even among the nine patients showing specificity for the single major autoepitope. In conclusion, we found that, although ACA-positive patients were both clinically and immunologically heterogeneous, in most respects the clinical expression appeared to be independent of the reactivity to the CENP-B autoepitope, a finding which suggests that identification of the target epitope of CENP-B is unlikely to assist in the clinical classification of the disease in ACA-positive patients. The identification of multiple B cell epitopes on CENP-B is consistent with the concept that the self-antigen drives the antibody response. However, factors other than CENP-B autoepitope specificity must determine the clinical expression of ACA responses.

Adult↗
PubMed1992

Properties of nine continuous B-cell lines established from enzootic bovine leukosis tumors.

We established 9 cell lines from 63 tumor cases of enzootic bovine leukosis and studied their properties. Cells of all lines formed small clumps and floated in culture medium, indicating growth. Four of the 9 cell lines were surface immunoglobulin (SIg)-positive, but the remaining 5 line cells were negative for SIg or, if SIg was detected, the percentage of SIg-positive cells was very low. Tests for the properties of the cells with monoclonal antibodies to lymphocytes revealed that the established line cells are B-lymphocytes. Morphological observation also revealed that they had the morphology of B-lymphoblastic cell. The results of E and EAC rosette assay were negative, but 6 of 8 cell lines were positive for EA rosetting. All the 9 cell lines reacted with MoAb C-143, which recognizes the tumor-associated antigen (TAA) of the EBL tumor cell. All 9 cell lines produced bovine leukosis virus (BLV). These results suggest that the 9 cell lines are tumor cells derived from B-lymphocytes of EBL.

Animals↗
PubMed1992

High potassium diets greatly increase growth-inhibiting agents in aortas of hypertensive rats.

High potassium diets greatly reduce intimal and medial thickening in stroke-prone spontaneously hypertensive rats (SHRSP). In vascular smooth muscle cells, transforming growth factor-beta (TGF-beta) inhibits proliferation. To test whether high potassium diets decrease aortic thickening through TGF-beta, we measured TGF-beta-like activity in medium bathing aortas from rats fed either normal potassium or high potassium diets. Five-week-old SHRSP were fed 6% high NaCl diets containing either normal (0.5%) potassium (11 rats) or high (2.1%) potassium (14 rats) for 7 weeks. Aortas were freshly excised and perfused for 3 hours with tissue culture medium at ordinary arterial pressures. TGF-beta-like activity in the acid-activated perfusing medium was assessed using the growth inhibitory action on mink lung cells. Growth inhibition was assessed by [3H]thymidine incorporation. In the medium perfusing the outside of the aorta, the growth inhibitory rates were 2.5 times higher in high potassium SHRSP than in normal potassium SHRSP (-49% versus -20%, p less than 0.03). Antibodies to TGF-beta 1 and TGF-beta 2 were added to other aliquots and did not alter the results whatsoever. Thus, the difference in growth inhibition was not due to differences in TGF-beta. The high potassium aortas released 2.5 times more growth-inhibiting agents than the normal potassium aortas. The same pattern of growth inhibition was also seen using vascular smooth muscle cells rather than mink lung cells (r = +0.818, p less than 0.001, n = 13). The increased growth inhibition of high potassium aortas was not due to an increased release of heparin.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

An antigenic determinant on human centromere protein B (CENP-B) available for production of human-specific anticentromere antibodies in mouse.

Centromere protein B (CENP-B) is one of the centromere DNA binding proteins constituting centromere heterochromatin throughout the cell cycles. Some components of mammalian centromeres including CENP-B are target antigens for autoimmune disease patients, often those with scleroderma. Recent isolations of CENP-B genes from human and mouse suggested that CENP-B was highly conserved among mammals. From the previous analysis of the reactivity of patient anticentromere sera, two autoepitopes have been located on the DNA binding domain at the amino-terminal region. The amino acid sequences for both the epitopes are perfectly conserved in the two species, human and mouse. In this study, to identify a human-specific antigenic determinant, the remaining two epitopes were further located in separate carboxyl-terminal regions of human CENP-B. Although the amino acid sequence of one epitope is identical to that of the corresponding region in mouse CENP-B, the other has a less homologous sequence. To confirm that the latter epitope was available for production of human-specific anticentromere antibodies, mice were immunized with the recombinant human CENP-B product. One serum that exclusively stained human centromere structure, but not that of other mammals, was identified in the immunofluorescence microscopic observation. The epitope analysis showed that the less conserved one was recognized by this serum. These results suggested that the corresponding region defines the antigenic determinants for the species specificity.

Amino Acid Sequence↗
PubMed1992

Renal microangiography and correlated histopathological observation of cows with nephropathy.

Seven Holstein-Friesian cows showing chronic nephropathy were studied by renal microangiography and its correlated histopathology. In cases of pyelonephritis associated with severe pathological lesions such as thickening of arterial walls, narrowing of the arterial and arteriolar lumen, and interstitial inflammation and abscess formation, patchy loss of the peritubular capillary plexus from the cortex to the medulla was clearly demonstrated by microangiography. Interlobular arteries were tortuous and attenuated or truncated. Opacification in the vasa rectae and interstitial capillaries was increased. Extensive non-perfused regions could be detected in the cortex. In cases of mild interstitial nephritis and moderate pyelonephritis, microangiography showed focal changes in the renal vasculature. Microangiography is thus shown to clearly demonstrate changes in the renal vasculature corresponding to the severity of the histopathological lesions.

Angiography↗
PubMed1992

Identification of effective component from a traditional herbal medicine and the inhibitory effects on experimental glomerular lesion in mice.

Effective constituents for renal disease were partially purified from a herbal prescription. The efficacy on renal diseases was examined using an experimental model system of glomerular lesion in mice induced by Agkistrodon acutus venom (Ac1-P). The extract of boiling water of the herbal prescription (P-3) was first fractionated by ether into an acidic fraction and a mixture of basic and neutral fractions. The acidic fraction was proved to be more effective and then further examined by thin layer chromatography and spectrophotometry. One of the main components was confirmed to be caffeic acid which had inhibitory effect on renal failure in mice by Ac1-P. This effect was considered to be caused by caffeic acid inhibiting the proteolytic enzyme activity of Ac1-P. Caffeic acid should thus have prophylactic or inhibitory effect on glomerular disease in which proteolytic enzymes may have pathogenic roles.

Animals↗
PubMed1992

Hibernating myocardium associated with coronary artery dissection and vasospastic angina.

Hibernating myocardium is an uncommon clinical state involving persistently impaired myocardial function. A 61-year-old man was admitted because of vasospastic angina. Coronary angiography revealed coronary artery dissection in the midportion of the right coronary artery, and segmental vasoconstriction was evoked by acetylcholine. In this patient, hibernating myocardium in the dissected region was clearly demonstrated by dipyridamole thallium-201 imaging. This report describes the first documented case of hibernating myocardium associated with coronary artery dissection, and the usefulness of dipyridamole thallium-201 imaging in the assessment of this state. Coronary artery spasm might be relevant to the etiology of coronary artery dissection.

Aortic Dissection↗
PubMed1992

[An experimental study of gastrointestinal motility during chronic large bowel obstruction].

Gastrointestinal motility and plasma PYY levels were investigated under chronic progressive large bowel obstruction in dogs. The obstruction device was applied around the descending colon at a laparotomy and gastrointestinal motility was recorded with strain gauge force transducers in the conscious state. Complete obstruction occurred at 26 days (21-33 days). The duration of postprandial interruption of motor complex (DIMC) in the antrum and duodenum were prolonged progressively, at partial obstruction (17.7 +/- 2.7 hr; p less than 0.05) and complete obstruction (23.0 +/- 4.0 hr; p less than 0.01) vs in control (13.7 +/- 1.9 hr), while DIMC in the small bowel showed no significant changes. Progressive obstruction caused hypermotility in the proximal colon to the obstruction and hypomotility in the distal colon. These dysmotility were improved after resection of the obstructed segment and anastomosis. Plasma PYY levels in the fasting state showed no significant increase at complete obstruction (42.6 +/- 14.5 pmol/l) vs in control (32.9 +/- 10.2 pmol/l).

Animals↗