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Biomedical subjects

K Yamane

Publications and source records attributed to K Yamane.

At least 73 records · Page 4Linked to original sources
PubMed2000

Retinoblastoma susceptibility protein, Rb, possesses multiple BRCT-Ws, BRCA1 carboxyl-terminus-related W regions with DNA break-binding activity.

The BRCT region, the carboxyl-terminus of BRCA1 (the breast cancer susceptibility gene 1 product), is ubiquitous in several proteins that participate in cell cycle checkpoints and DNA repair. We have previously shown that the BRCT regions of TopBP1 (DNA topoisomerase II binding protein 1) and BRCA1 bound DNA breaks. A BRCT-related region, BRCT-W1, in the retinoblastoma susceptibility gene product (Rb) also could bind DNA fragments, independently of DNA sequences. Five BRCT-W regions were found in the Rb family. All BRCT-Ws of Rb bound DNA fragments. Electron microscopy and treatment with an exonuclease showed that BRCT-Ws bound double-strand DNA breaks. Since some BRCTs are exceptional common relating elements in tumor suppression, our findings reveal novel aspects of the tumor suppression mechanism.

Amino Acid Sequence↗
PubMed2000

Molecular cloning and functional analysis of apoxin I, a snake venom-derived apoptosis-inducing factor with L-amino acid oxidase activity.

We previously purified apoxin I, an apoptosis-inducing factor with L-amino acid oxidase (LAO) activity, from Western diamondback rattlesnake venom. To determine the primary structure of apoxin I, we cloned its cDNA. The amino acid sequence showed that apoxin I has an FAD binding domain and shares homology with L-amino acid oxidase (LAO) from Neurospora crassa, human monoamine oxidase B, and mouse interleukin 4-induced F1G1 protein. The full-length apoxin I has an N-terminal signal sequence that is processed in mature apoxin I in venom. When the apoxin I gene was transfected into human 293T cells, the recombinant protein was expressed in the cells, and a significant amount of apoxin I was secreted into the medium. The secreted recombinant apoxin I protein showed LAO and apoptosis-inducing activity, but the recombinant protein in the cells did not, suggesting that maturation and secretion of the apoxin I protein is needed for its activity. Treating the transfected cells with tunicamycin inhibited the secretion and LAO activity of the recombinant apoxin I. In addition, deleting the amino-terminal region flanking the signal sequence, the FAD-binding domain and the carboxy-terminal region abolished the secretion and LAO activity of the recombinant proteins. These results indicate that in order for apoxin I to become active, these regions and posttranslational modification, such as N-glycosylation, are required.

Amino Acid Oxidoreductases↗
PubMed2000

Increased serum levels of soluble vascular cell adhesion molecule 1 and E-selectin in patients with localized scleroderma.

BACKGROUND: The serum levels of soluble forms of vascular cell adhesion molecule 1 (sVCAM-1) and E-selectin (sE-selectin) can be used as a marker of endothelial activation. OBJECTIVE: We investigated whether the serum level of sVCAM-1 and sE-selectin in patients with localized scleroderma (LSc) was correlated with the clinical or serologic features of this disease. METHODS: Serum samples from 59 patients with LSc, 20 patients with systemic sclerosis (SSc) and 29 healthy controls were examined using specific enzyme-linked immunosorbent assays. RESULTS: The serum levels of sVCAM-1 and sE-selectin in patients with LSc were significantly higher than those of the healthy controls. The serum levels of sVCAM-1 and sE-selectin were correlated with both the number of sclerotic lesions and the number of involved areas. CONCLUSION: These results indicate that the serum levels of sVCAM-1 and sE-selectin may reflect the extent of the skin involvement (ie, the disease severity) and may be useful for monitoring the in vivo states of endothelial activation in LSc.

Adult↗
PubMed2000

Telomerase activity in oral and maxillofacial tumors.

Telomerase activity was measured in biopsy specimens as well as surgically resected tissues of 39 oral squamous cell carcinomas (SCCs), 22 oral leukoplakias, 13 normal oral mucosas, 12 malignant salivary gland tumors, 10 benign salivary tumors and five normal salivary gland tissues adjacent to tumors using a polymerase chain reaction (PCR)-based telomerase assay. Telomerase activity was detectable in 38.5% (5/13) of normal oral mucosa samples, 54.5% (12/22) of leukoplakia samples, 82.1% (32/39) of oral SCC samples, 83.3% (10/12) of malignant salivary gland tumor samples and 0% (0/10, 0/5) of benign salivary gland tumor and normal salivary gland samples. High-level enzyme activities were seen in 20% (3/15) of mild dysplasia specimens, 50% (2/4) of moderate-severe dysplasia specimens, 48.7% (19/39) of oral SCC tissue specimens, and no high activity was seen in the normal mucosa and hyperkeratosis specimens (P for trend, <0.001). We also analyzed the proliferative activity of dysplastic leukoplakia, oral SCC, and salivary gland tumor specimens using Ki-67 immunohistochemistry. The Ki-67 labeling indices (LI) were significantly higher in dysplastic leukoplakia and oral SCC with high telomerase activity than in dysplastic leukoplakias and oral SCC with low and negative telomerase activity (P<0.01 and P<0.05). These results indicate that telomerase activity has some correlation with the progression of multistep oral carcinogenesis with the cellular proliferation, and also indicate that telomerase may be a specific marker used to distinguish malignant salivary gland tumors from their benign counterparts.

Biomarkers, Tumor↗
PubMed2000

Increased serum levels of soluble vascular cell adhesion molecule-1 and soluble E-selectin in patients with polymyositis/dermatomyositis.

BACKGROUND: Elevated levels of soluble vascular cell adhesion molecule-1 (sVCAM-1) and soluble E-selectin (sE-selectin) have previously been reported in patients with various inflammatory diseases, but not in patients with polymyositis/dermatomyositis (PM/DM). OBJECTIVES: To determine serum levels and significance of sVCAM-1 and sE-selectin in patients with PM/DM. PATIENTS AND METHODS: Serum samples from 36 PM/DM patients, 30 patients with systemic sclerosis and 25 healthy control subjects were examined using specific enzyme-linked immunosorbent assay systems. RESULTS: The serum levels of sVCAM-1 in the PM/DM patients were significantly higher than those in the healthy controls. The elevated serum sVCAM-1 levels were correlated with the values of elevated erythrocyte sedimentation rate and elevated serum hyaluronate levels in the PM/DM patients. The serum sE-selectin levels in the PM/DM patients were also significantly higher than those in the healthy controls. The elevated serum sE-selectin levels were correlated with the incidence of elevated creatine kinase activities. The concentrations of serum sE-selectin were correlated with the serum tissue inhibitor of metalloproteinase-1 concentrations in the PM/DM patients (r = 0.53). CONCLUSIONS: These results suggest that serum sVCAM-1 and sE-selectin levels might be useful for detecting disease activity in patients with PM/DM.

Adolescent↗
PubMed2000

Intravenous detergent poisoning.

CASE REPORT: In the literature regarding surfactant poisoning, the route of exposure has almost always been oral. We report a case in which about 40 mL of bath detergent for home use was self-injected. The primary pathophysiologic effects were relative hypovolemia and cardiac dysfunction. The patient experienced frequent ventricular tachycardia, acute renal failure, rhabdomyolysis, hemolysis, and coagulation dysfunction. Intensive care included the administration of antiarrythmial agents and hemodialysis. The patient survived and was discharged from our hospital without sequelae.

Acute Kidney Injury↗
PubMed2000

DNA polymorphism at the cytosolic phosphoglucose isomerase (PgiC) locus of the wild plant Arabidopsis thaliana.

DNA variation in a 4.7-kb region of the cytosolic phosphoglucose isomerase (PgiC) locus was investigated for 21 ecotypes of Arabidopsis thaliana. The estimated nucleotide diversity was 0.0038, which was one-third of those in previously investigated loci. Since most of the nucleotide variations (93%) were singleton and doubleton, Tajima's test statistic was significantly negative. About 50% of nucleotide polymorphisms in exons were replacement, which caused significance in McDonald and Kreitman's test when compared with Arabis gemmifera and Cardaminopsis petraea. These results indicated that DNA polymorphism at the PgiC locus was not under neutrality. There were two divergent sequence types in the PgiC region, which were associated with allozyme variation. The Fast allozyme was shown to have originated from the Slow allozyme, since two outgroup species had the Slow form. A phylogenetic tree of ecotypes with the Fast allozyme had the shape of a star phylogeny. Mismatch distribution of the Fast allozyme ecotypes resembled that expected under an expanding population model. These results suggest positive selection for the Fast allozyme of the PGIC in A. thaliana.

Arabidopsis↗
PubMed2000

Crystal structure of alkalophilic asparagine 233-replaced cyclodextrin glucanotransferase complexed with an inhibitor, acarbose, at 2.0 A resolution.

The product specificity of cyclodextrin glucanotransferase (CGTase) from alkalophilic Bacillus sp. #1011 is improved to near-uniformity by mutation of histidine-233 to asparagine. Asparagine 233-replaced CGTase (H233N-CGTase) no longer produces alpha-cyclodextrin, while the wild-type CGTase from the same bacterium produces a mixture of predominantly alpha-, beta-, and gamma-cyclodextrins, catalyzing the conversion of starch into cyclic or linear alpha-1,4-linked glucopyranosyl chains. In order to better understand the protein engineering of H233N-CGTase, the crystal structure of the mutant enzyme complexed with a maltotetraose analog, acarbose, was determined at 2.0 A resolution with a final crystallographic R value of 0.163 for all data. Taking a close look at the active site cleft in which the acarbose molecule is bound, the most probable reason for the improved specificity of H233N-CGTase is the removal of interactions needed to form a compact ring like a-cyclodextrin.

Acarbose↗
PubMed2000

Clinical and laboratory features of scleroderma patients with pulmonary hypertension.

OBJECTIVE: Pulmonary hypertension (PH) is a frequent cause of death in patients with systemic sclerosis (SSc). In this study, we examined the occurrence of PH and investigated the clinical and laboratory features of SSc patients with PH. METHODS: A cross-sectional study of 125 Japanese patients with SSc was conducted using Doppler echocardiography, other multiple cardiopulmonary tests, and laboratory examination. RESULTS: PH (systolic pressure >40 mmHg) was diagnosed in 20 patients (16%) by Doppler echocardiography. In the six patients who had secondary pulmonary hypertension (SPH), PH was due to severe pulmonary fibrosis; 14 patients had isolated pulmonary hypertension (IPH). An elevated erythrocyte sedimentation rate (ESR) and increased immunoglobulin G (IgG) were found in a significantly greater proportion of the patients with PH than in those without PH. The incidence of pitting scars/ulcers was significantly greater in the patients with SPH than in those without PH. CONCLUSION: Elevated ESR and increased IgG were common features of scleroderma patients with PH, and scleroderma patients with SPH were inclined to have pitting scars/ulcers.

Adult↗
PubMed2000

Serum KL-6 in adult patients with polymyositis and dermatomyositis.

OBJECTIVE: To determine the serum levels of KL-6, a mucin-like high-molecular-weight glycoprotein, in polymyositis/dermatomyositis (PM/DM) patients. METHODS: Serum samples from 42 adult PM/DM patients and 38 healthy control subjects were examined using specific enzyme-linked immunosorbent assay (ELISA) systems. RESULTS: The serum levels of KL-6 in the PM/DM patients were significantly higher than those of the healthy controls. The elevated serum KL-6 levels correlated with the presence of interstitial lung disease (ILD) and decreased percentage diffusing capacity of carbon monoxide (%DLco) in the PM/DM patients. The serum KL-6 levels inversely correlated with %DLco and percentage vital capacity. Additionally, the serum KL-6 levels were elevated in five of the seven DM patients with malignant neoplasia. CONCLUSIONS: These results suggest that the serum KL-6 level might be a useful serum marker for ILD and internal malignancy in PM/DM.

Adult↗
PubMed2000

Crystallization and preliminary X-ray diffraction analysis of a cytochrome P450 (CYP119) from Sulfolobus solfataricus.

CYP119 is a cytochrome P450 with a molecular weight of 43 kDa which has been isolated from the thermophilic archaeon Sulfolobus solfataricus. This enzyme is extremely stable to high temperature and high pressure. The first crystallization and preliminary crystallographic study of CYP119 is reported here. Crystals of CYP119 were obtained by the sitting-drop vapour-diffusion method using a precipitant solution containing 20%(w/v) PEG 4000 and 0.2 M sodium thiocyanate at pH 6.4. Using synchrotron radiation, the CYP119 crystal diffracted to 1.84 A resolution. It belongs to the tetragonal space group P4(3)2(1)2, with unit-cell parameters a = b = 86.17 (0.07), c = 221.11 (0.04) A, in which the numbers in parentheses describe the standard deviations. Assuming two molecules of the CYP119 per asymmetric unit, the calculated molar volume (V(m)) is 2.38 A(3) Da(-1). Bijvoet and dispersive anomalous difference Patterson maps show a clear peak corresponding to the haem irons. The complete crystallographically defined structure is currently in progress using MIR (multiple isomorphous replacement) and MAD (multiwavelength anomalous diffraction) techniques.

Archaeal Proteins↗
PubMed2000

Palmar fasciitis and polyarthritis associated with gastric carcinoma: complete resolution after total gastrectomy.

Palmar fasciitis and polyarthritis (PFA) is a rare paraneoplastic rheumatic syndrome characterized by flexion contractures of both hands and thickening of palmar fascia. Several reports have suggested that this syndrome is a tumor-associated autoimmune disorder. We report a 44-year-old Japanese man who presented with flexion contractures of both hands associated with thickening of palmar fascia and polyarthritis. These clinical pictures were suggestive of PFA associated with occult neoplasm. Upper gastrointestinal endoscopic examination revealed advanced gastric cancer. Resection of the cancer resulted in a gradual resolution of palmar fasciitis and polyarthritis. This clinical course suggests an underlying tumor-related immunologic process in this syndrome.

Adenocarcinoma↗
PubMed2000

Circulating levels of soluble CD30 are increased in patients with localized scleroderma and correlated with serological and clinical features of the disease.

OBJECTIVE: To determine serum soluble CD30 (sCD30) levels in patients with localized scleroderma. METHODS: Serum soluble CD30 levels were assayed by a sensitive ELISA in 55 patients with localized scleroderma, in 15 with systemic sclerosis (SSc), and in 20 healthy controls. RESULTS: Serum levels of sCD30 were significantly higher in patients with localized scleroderma than in healthy controls. Serum levels of sCD30 were correlated with the number of sclerotic lesions, the number of involved areas, levels of anti-histone antibody IgM, and levels of interleukin 6. sCD30 levels in sera from patients with SSc were also significantly higher than in healthy controls. CONCLUSION: These results suggest possible involvement of Th2 cells in the immunopathogenesis in localized scleroderma, and serum sCD30 levels may be helpful in following the outcome of the disease.

Adolescent↗
PubMed2000

Changes in cerebral blood flow after carotid endarterectomy.

We evaluated changes in cerebral blood flow (CBF) after carotid endarterectomy (CEA) in patients with internal carotid (ICA) stenosis. We studied 46 patients with ICA stenosis who underwent CEA. The mean age of the patients was 63 years, and their mean ICA stenosis was 73%. CBF in the middle cerebral artery territory was measured with xenon-enhanced CT tomography (Xe-CT) before and 3 weeks after CEA. In addition, cerebrovascular reactivity (CVR) was measured after intravenous administration of acetazolamide (ACZ) in 16 patients. There was no significant relationship between the degree of stenosis and CBF. Ten patients had decreased CBF before CEA, and CBF improved in nine of these after CEA. The CVR in 6 of 7 patients with impaired CVR before CEA improved to varying degrees after CEA. The CBF in patients with ICA stenosis varied according to the degree of collateral circulation. In conclusion, CEA can increase CBF and improve CVR in patients with low CBF or low CVR by restoring blood flow through the ICA.

Carotid Artery, Internal↗
PubMed2000

Serum levels of KL-6 as a useful marker for evaluating pulmonary fibrosis in patients with systemic sclerosis.

OBJECTIVE: KL-6 is a mucin-like glycoprotein that is strongly expressed on type II pneumocytes in the lung. Circulating KL-6 has been shown to be a sensitive marker of the disease activity of interstitial lung diseases. We determined the serum levels of KL-6 in patients with systemic sclerosis (SSc) and investigated whether these levels would serve as a useful marker of pulmonary fibrosis (PF) in patients with SSc. METHODS: The serum KL-6 levels were determined using a specific ELISA in 91 patients with SSc, and in 38 healthy controls. RESULTS: The serum levels of KL-6 were significantly higher in patients with SSc than in healthy controls (923+/-860 vs. 382+/-55 U/ml; p<0.0001). The serum KL-6 levels of the patients with diffuse cutaneous SSc (dSSc) tended to be higher than those with limited cutaneous SSc (ISSc) (1054+/-1000 vs. 800+/-694 U/ml), but there was no significant difference between these 2 groups. The serum KL-6 levels in the patients with PF were significantly elevated compared to those without PF (1283+/-1056 vs. 520+/-148 U/ml; p<0.0001). Moreover, DLCO and VC were also significantly decreased in the patients with elevated KL-6 levels compared to those with normal levels (62+/-22% vs. 72+/-17%, p<0.05; 87 +/-20% vs. 100+/-18%, p<0.01, respectively). CONCLUSION: Serum KL-6 level may be a useful serum marker for evaluating pulmonary fibrosis in patients with SSc.

Adult↗
PubMed2000

The relationship between serum immunoglobulin levels and pulmonary involvement in systemic sclerosis.

OBJECTIVE: To examine the relationship between serum immunoglobulin (Ig) levels and pulmonary function in patients with systemic sclerosis (SSc). METHODS: Twenty-four patients with SSc who had at least 2 sets of pulmonary function tests (PFT) at intervals of more than one year were eligible. Multiple linear regression models were constructed for prediction of the annualized rates of change of forced vital capacity (FVC), carbon monoxide diffusing capacity (DL(CO)), and DL(CO) per unit alveolar volume (K(CO)). RESULTS: The rates of change of FVC and K(CO) correlated with the annualized rate of change of IgG (p < 0.001 and p = 0.005, respectively), and the rate of change of DL(CO) correlated with the serum IgM level at the first PFT (p = 0.020) and with the annualized rate of change of IgG (p = 0.007). CONCLUSION: The rates of change of serum Ig levels are associated with those of pulmonary function in SSc. Use of this model may assist investigation of pulmonary involvement.

Adult↗