Biomedical subjects
Publications and source records attributed to Kazuo Takeuchi.
[Structure: see text] A 1,4-bis(phenyl)-1,4-dihydro[60]fullerene resulting from an efficient nucleophilic substitution has been obtained by reaction of a fullerene epoxide, C60O, with nucleophilic aromatic compounds in the presence of boron trifluoride etherate as a Lewis acid.
BACKGROUND: In the present study, we developed models to predict unresponsiveness to intravenous immunoglobulin (IVIG) in Kawasaki disease (KD). METHODS AND RESULTS: We reviewed clinical records of 546 consecutive KD patients (development dataset) and 204 subsequent KD patients (validation dataset). All received IVIG for treatment of KD. IVIG nonresponders were defined by fever persisting beyond 24 hours or recrudescent fever associated with KD symptoms after an afebrile period. A 7-variable logistic model was constructed, including day of illness at initial treatment, age in months, percentage of white blood cells representing neutrophils, platelet count, and serum aspartate aminotransferase, sodium, and C-reactive protein, which generated an area under the receiver-operating-characteristics curve of 0.84 and 0.90 for the development and validation datasets, respectively. Using both datasets, the 7 variables were used to generate a simple scoring model that gave an area under the receiver-operating-characteristics curve of 0.85. For a cutoff of 0.15 or more in the logistic regression model and 4 points or more in the simple scoring model, sensitivity and specificity were 86% and 67% in the logistic model and 86% and 68% in the simple scoring model. The kappa statistic is 0.67, indicating good agreement between the logistic and simple scoring models. CONCLUSIONS: Our predictive models showed high sensitivity and specificity in identifying IVIG nonresponders among KD patients.
OBJECTIVE: To investigate the role of corticosteroids in the initial treatment of Kawasaki disease (KD). STUDY DESIGN: Between September 2000 and March 2005, we randomly assigned 178 KD patients from 12 hospitals to either an intravenous immunoglobulin (IVIG) group (n = 88; 1 g/kg for 2 consecutive days) or an IVIG plus corticosteroid (IVIG+PSL) group (n = 90). The primary endpoint was coronary artery abnormality (CAA) before a 1-month echocardiographic assessment. Secondary endpoints included duration of fever, time to normalization of serum C-reactive protein (CRP), and initial treatment failure requiring additional therapy. Analyses were based on intention to treat. RESULTS: Baseline characteristics of groups were similar. Fewer IVIG+PSL patients than IVIG patients had a CAA before 1 month (2.2% vs 11.4%; P = .017). The duration of fever was shorter (P < .001) and CRP decreased more rapidly in the IVIG+PSL group than in the IVIG group (P = .001). Moreover, initial treatment failure was less frequent (5.6% vs 18.2%; P = .010) in the IVIG+PSL group. All patients assigned to the IVIG+PSL group completed treatment without major side effects. CONCLUSIONS: A combination of corticosteroids and IVIG improved clinical course and coronary artery outcome without causing untoward effects in children with acute KD.
OBJECTIVE: The aim of this study was to estimate the number of autoimmune pancreatitis (AIP) patients in Japan and evaluate the influence of steroid therapy on the course of diabetes mellitus (DM) in AIP. METHODS: A total of 2972 departments were randomly selected with hospital stratification throughout Japan. We sent a questionnaire asking the selected departments to report the number of patients who had visited their hospital in 2002 and who fulfilled the diagnostic criteria for AIP set by the Japan Pancreas Society. We then sent a second questionnaire asking for the details of the clinical course of DM, if any, and the treatments used for AIP. RESULTS: The annual number of AIP in Japan was estimated as approximately 900 (95% confidence interval 670-1100) or 0.71 per 100,000 individuals in the Japanese population. In the second survey, 66.5% of the 167 patients of AIP were reported as being complicated with DM. Among the AIP patients with DM (n = 93), 52% of the patients started to show DM simultaneously with the onset of AIP, and 33% of the patients had DM before the onset of AIP. Following steroid therapy, 55% and 36% of these patient groups showed improvement of DM control, respectively. On the other hand, less than 20% of patients showed newly developed DM or showed exacerbation of DM control after steroid therapy. The older the patients were, the higher were the rates of new development or exacerbation of DM. CONCLUSIONS: These findings indicated that steroid therapy has a beneficial effect on the clinical courses of DM in approximately half of AIP patients. However, it also has negative effect on glucose tolerance in some patients, particularly older patients, and thus, careful observation for involvement of DM should be required in AIP patients treated with steroids.
The critical load determined by the scratch test is regarded to be a representative measure of coating adhesion in the field of engineering. This study aimed to evaluate the method for its usefulness for assessing the mineralized tissue-titanium interface strength. Osteoblastic cells derived from rat bone marrow were cultured on polystyrene, titanium-coated polystyrene, and titanium disks with either a machined or dual-acid etched surface. Nano-scratch testing was performed on mineralized tissue specimens at culture day 28. The scratch path was monitored by light microscopy until complete delamination of mineralized tissue from the substrate occurred, and the required force was recorded as the critical load. Energy-dispersive spectroscopic analysis was used to verify the delamination. The mean critical load values (+/- standard deviations) were as follows: polystyrene 31 mN (+/-1), titanium-coated polystyrene 67 mN (+/-4), machined titanium 76 mN (+/-4), DAE titanium 107 mN (+/-3), with statistical differences (P < 0.05; ANOVA). No elemental calcium and phosphorous were observed in the delaminated areas. The nano-scratch test applied to cultured mineralized tissue differentiated the critical load from various culture conditions: polystyrene vs. titanium; titanium with different surface topographies. Culturing mineralized tissue on titanium, especially on roughened surfaces, increased the tissue critical load. The nano-scratch test may be useful to evaluate mineralized tissue adhesion properties in titanium cultures.
The biological mechanisms underlying bone-titanium integration and biomechanical properties of the integrated bone are poorly understood. This study assesses intrinsic biomechanical properties of mineralized tissue cultured on titanium having different surface topographies. The osteoblastic phenotypes associated with mineral deposition and collagen synthesis underlying the biomechanical modulation are also reported. Rat bone marrow-derived osteoblastic cells were cultured either on the machined titanium disc or acid-etched titanium disc. Nano-indentation study of day 28 culture revealed that the mineralized tissue on the acid-etched surface shows 3-3.5 times greater hardness than that on the machined surface (p < 0.01). Elastic modulus of the mineralized tissue was also 2.5-3 times greater on the acid-etched surface than on the machined surface (p < 0.01). After 28 days of culture, mineralized nodule area was significantly lower on the acid-etched surface than on the machined surface (p = 0.0105), while total calcium deposition did not differ between the two surfaces, indicating denser mineral deposition on the acid-etched surface. Osteopontin and osteocalcin gene expressions assayed by the reverse transcriptase-polymerase chain reaction were upregulated in the acid-etched titanium culture. Collagen synthesis measured by Sirius red stain-based colorimetry was 1.5-10 times higher on the acid-etched surface than on the machined surface in the initial culture period of day 1 to day 14 (p < 0.0001). The amount of collagen synthesis corresponded with the enhanced gene expression of prolyl 4-hydroxylase, a key enzyme for post-translational modification of collagen chains. Scanning electron microscopic images revealed that tissue cultured on the acid-etched titanium exhibited plate-like, compact surface morphology, while the tissue on the machined titanium appeared porous and was covered by fibrous and punctate structures. We conclude that culturing osteoblasts on rougher titanium surfaces enhances hardness and elastic modulus of the mineralized tissue, associated with condensed mineralization, accelerated collagen synthesis, and upregulated expression of selected bone-related genes.
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An incorporation of ND(3) into protonated ammonia cluster ions NH(4)(+)(NH(3))(n-1) (n=3-9), together with a dissociation of the cluster ions, was observed in the collision of the cluster with ND(3) at collision energies ranging from 0.04 to 1.4 eV in the center-of-mass frame. The branching fractions of the cluster ion species produced in the reactions were obtained as a function of the collision energy. The branching fractions of the incorporation products were successfully explained in terms of the Rice-Ramsperger-Kassel (RRK) theory at collision energies lower than the binding energy of the cluster ion. In addition, the internal energy distributions of the parent cluster ions were determined, and found to be in good agreement with those predicted using the evaporative ensemble model. In incorporations at collision energies lower than the binding energy of the cluster ion, all of the collision energy was transferred to the internal energy of the cluster ions; subsequently, an evaporation of ammonia molecules occurred in an equilibrium process after a complete energy redistribution in the clusters. In contrast, at collision energies higher than the binding energy of the cluster ion, a release of an ammonia molecule from the incorporation products occurred in a nonequilibrium process. The transition from the complex mode to the direct mode in the incorporation was observed at collision energies approximately equal to the binding energy. On the other hand, the collision energy dependence of the cross sections for the dissociation and for a nonreactive collision were estimated by a RRK simulation in which the collision energy transfer was interpreted by using the classical hard-sphere collision model. A relationship between reactivity and reaction modes in the collision of NH(4)(+)(NH(3))(4) with ND(3) is discussed via a comparison of the experimental results with the RRK simulation.
BACKGROUND: Heparanase is considered to play an important role in tumor invasion and hematogenous metastasis. The aim of this study was to determine the expression of heparanase in colorectal cancer to evaluate its prognostic value. METHODS: We analyzed heparanase mRNA derived from 130 colorectal cancer patients by reverse transcription polymerase chain reaction (PCR), compared its expression with clinicopathologic factors, and performed statistical analysis. To investigate the relationship between heparanase expression and tumor angiogenesis, 81 primary colorectal tumors were immunostained by use of a monoclonal anti-CD34 antibody. RESULTS: Thirty three of 130 cancer tissues overexpressed heparanase. There were significant correlations between heparanase expression and serosal invasion, venous invasion, and liver metastasis. Multivariate analyzes revealed that heparanase mRNA overexpression was a significant independent risk factor for hematogenous metastasis in colorectal cancer. Among 104 patients who underwent curative resection, heparanase expression correlated with a high recurrence. The 5-year survival rate was 84.6% for patients with heparanase negative tumors, and 47.7% for those with heparanase overexpression; these differences between two groups of patients were significant. In multivariate analysis using the Cox regression model, heparanese expression emerged as an independent prognostic indicator. Moreover, the tumor angiogenesis of heparanase-positive tumors determined with a monoclonal anti-CD34 antibody was significantly higher than that of heparanase-negative tumors. CONCLUSIONS: These results indicated that Heparanase expression may be an important role in invasion and hematogenous metastasis, and may be a biologic marker of prognostic significance in colorectal cancer patients.
OBJECTIVE: To evaluate the masticatory performance of elderly people at the age of 80 years. SUBJECTS: A total of 283 individuals of 80 years of age took part in a general and dental health survey. MAIN OUTCOME MEASURES: A dental examination including the number of remaining teeth, occlusion, prostheses, bite force recording, and a questionnaire regarding masticatory performance were recorded. SETTING: Five municipalities (Okazaki city, Tokoname city, Tahara town, Atsumi town and Minami-chita town) in Aichi prefecture, Japan. RESULTS: There were 20 or more teeth in 7.4% subjects, and 44.5% were edentulous. Subjects with no occlusion accounted for 77.4% of the total. Subjects with prostheses accounted for 90.8%. Maximum bite force and masticatory ability score for patients with 20 or more teeth or not wearing prostheses were higher than other groups. The non-wearing prostheses group had a low masticatory ability score. CONCLUSION: Most of the 80-year-old individuals recovered their masticatory ability with the assistance of prostheses. Several individuals with 20 or more remaining teeth or without removable dentures present in both jaws had a high score for bite forces and masticatory abilities.
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Patients troubled with primary sclerosing cholangitis (PSC) and ulcerative colitis (UC) are at high risk for cholangiocarcinoma, whereas cancer of the gallbladder (GBC) is rarely reported to develop in that population. A Japanese man aged 62 years with a 14-year history of PSC and UC had been found to have a protruding lesion of the gallbladder by screening sonography. The preoperative examination suggested the lesion to be GBC at an early stage. Pathology examination after cholecystectomy proved that the lesion was papillary adenocarcinoma localized in the mucosal layer. Although the prognosis of GBC is poor, the outcome of cholecystectomy against early GBC is relatively good. Early detection of the tumor is required for a better prognosis of patients with GBC. According to the review of the literature, PSC and UC patients are regarded as a high-risk group not only for cholangiocarcinoma but also GBC. It is advocated that clinicians perform repeated radiographic examinations including sonography for patients with PSC and UC even if the diseases are being controlled.
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The goal of this study was to assess the spikes systematically and to clarify an epileptc abnormality induced by electroconvulsive therapy (ECT). Our subjects were 20 psychotic patients with no spikes on prior EEGs. ECT was performed by applying electrical current to both sides of the patient's temple every 2 or 3 days for a period of between 1-4 weeks. The first EEG examination was performed either on the day that the ECT course was completed or on the following day. Subsequent EEG examinations were performed at intervals of 2 or 3 days. Thirteen of the 20 patients showed spikes. There were no significant differences in age, gender, diagnosis, or type of ECT. Patients with spikes had significantly more ECT sessions than those without spikes. The spikes were present in the frontal, temporal and central areas, predominantly frontal, anterior temporal and mid-temporal region, and almost disappeared in 1-3 weeks. The occurrence of spikes immediately after ECT was demonstrated. Although this abnormality was transient, it could indicate that in humans ECT causes the early stage of kindling phenomenon as a result of repeated application, and that the temporal lobe seems to play a major role in order to induce the phenomenon.
The Anorectic Behavior Observation Scale (ABOS) is a questionnaire developed to obtain information from relatives about behaviors and attitudes of patients with eating disorders. The original report of the ABOS revealed three factors. This is the first study to confirm the factor structure by use of confirmatory analyses. Relatives of 102 patients with eating disorders completed the ABOS, and exploratory factor analyses were performed. Confirmatory factor analyses were performed for this Japanese sample, and the fitness of the factor structure was compared between that in the original report proposed by Vandereycken and that used in the present study. A three-factor structure was revealed by the data of Japanese patients, including factor I (eating behavior meeting the criteria of anorexia; concern with weight, foods, and denial), factor II (bulimia; including bingeing, disposing, furtive eating and purging, and talk about thinness and dieting), and factor III (hyperactivity, eating slowly, and chopping food into very small pieces). Confirmatory analyses supported the improvement of fitness in this modified three-factor structure in comparison with the original three-factor model. This Japanese ABOS study revealed three dimensions, which differed from the original subscales in Belgium. Cross-cultural differences were observed, though the ABOS may be useful in Japan as an instrument for assessing eating disorders.
A hitherto undetected type of C(60)O(3) isomer was found in the reaction solution of C(60) with m-chloroperoxybenzoic acid by means of a chromatographic technique using two different columns. Both electronic spectroscopy and atmospheric pressure chemical ionization (APCI) mass-spectroscopy examinations show its C(3)(nu) symmetry, in which three oxygen atoms are added onto one benzenoid ring of C(60).
BACKGROUND AND OBJECTIVES: Variants of CD44 have been proposed to be important in promoting tumor progression and metastasis. We attempted to determine the expression of CD44v6 product in advanced gastric cancer and to evaluate its prognostic value. METHODS: The expression of CD44v6 was analyzed immunohistochemically in advanced gastric cancers using monoclonal antibody, 44-2V. We investigated the relationship between CD44v6 expression and prognosis in 201 gastric cancer patients. RESULTS: Ninety-five (47.3%) of 201 cancer tissues expressed CD44v6. The expression of CD44v6 protein was significantly higher in differentiated, adenocarcinoma than in diffuse type carcinoma. The CD44v6-positive cancers were more frequently associated with hematogenous metastasis. There was no significant correlation between CD44v6 immunoreactivity, and prognosis among the combined cases. Among patients with differentiated adenocarcinoma, however, the prognosis was significantly poorer in patients with CD44v6-positive tumors than in those with CD44v6-negative tumors. CONCLUSIONS: CD44v6 protein may have an important role in hematogenous metastasis, and may be a biologic marker of prognostic significance in differentiated type gastric cancers.
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