Biomedical subjects

Y Arai

Publications and source records attributed to Y Arai.

At least 73 records · Page 4Linked to original sources

PubMed2001

Sex differences in children's free drawings: a study on girls with congenital adrenal hyperplasia.

Sex differences are recognized in children's free drawings with respect to motifs, colors, figure compositions, and expression. Boys tend to draw mobile objects and mechanical objects with dark or cold colors and often use bird's-eye-view composition when they draw pictures, whereas girls like to draw human motifs (especially girls and women), flowers, and butterflies with light and warm colors and tend to arrange motifs in a row on the ground. Analyses were made on the drawings of girls with congenital adrenal hyperplasia (CAH) and unaffected boys and girls, using masculine and feminine indexes. Sex difference in masculine and feminine indexes was clear in the drawings by unaffected boys and girls. Their drawings do not or mostly do not contain characteristics typical of the opposite sex. Compared with those of unaffected girls, the pictures of CAH girls more strongly showed masculine characteristics. The feminine index for the pictures of CAH girls was significantly lower than that for unaffected girls, while the masculine index for CAH girls was significantly higher than that for unaffected girls. Furthermore, the masculine index for CAH girls was not significantly different from that of unaffected boys. These results suggest that androgen exposure during fetal life may contribute to shaping masculine characteristics in children's free drawings.

Adrenal Hyperplasia, Congenital↗

PubMed2001

One-stage thoracic aortic aneurysm treatment and coronary artery bypass grafting.

OBJECTIVE: The treatment of thoracic aortic aneurysm accompanied by ischemic heart disease presents a surgical challenge and has up to now shown a high hospital mortality rate. This report discusses the factors contributing to improved results in these cases. METHODS: We conducted a retrospective analysis of the records of 24 consecutive patients who had undergone replacement of thoracic aorta with combined coronary artery bypass grafting (CABG) between May 1991 and October 1998. Fifteen patients received total arch replacement (Arch-with-CABG Group), and the other 9 patients received the Bentall operation (Bentall-with-CABG Group). These results were compared with those patients who had undergone replacement of the thoracic aorta without CABG (Without-CABG Group). RESULTS: In the combined CABG groups, the overall operative mortality rate was 16.7%. In comparison with the Arch-without-CABG Group, there was a significantly longer cardiopulmonary bypass time and longer selective cerebral perfusion time in the Arch-with-CABG Group. However, no significant difference was observed in postoperative complications between the two groups. In addition, there was no significant difference in either actuarial survival or the cardiac-event-free rate at 5 years between the replacement of thoracic aorta with- and without-CABG Groups (83.1% vs. 90.4%, and 78.5% vs. 77.7%, respectively). No reoperation and no late death were observed during the follow-up period (mean 21.3 months). CONCLUSIONS: We concluded that replacement of the thoracic aorta combined with CABG can be carried out safely, and that revascularization for coronary artery disease is useful for preventing any occurrence of cardiac event.

Aged↗

PubMed2001

Involvement of the NUP98 gene in a chromosomal translocation t(11;20)(p15;q11.2) in a patient with acute monocytic leukemia (FAB-M5b).

We report here a case of acute monocytic leukemia (M5b subtype according to the French-American-British [FAB] classification) with chromosomal translocation t(11;20)(p15;q11.2). Fluorescence in situ hybridization analysis with a probe for the NUP98 gene, which is located at chromosome band 11p15, showed that the probe hybridized to both derivative chromosomes 11 and 20 as well as to the remaining normal chromosome 11, indicating that the NUP98 gene was split and involved in this translocation. This is the first report of t(11;20)(p15;q11.2) involving the NUP98 gene in overt leukemia.

Aclarubicin↗

PubMed2001

Development of the fluorometric ELISA method for determination of alpha1-microglobulinuria in a cadmium-polluted area in Japan.

OBJECTIVES: To evaluate the usefulness of a newly developed fluorometric enzyme-linked immunosorbent assay (fluorometric ELISA) method for quantification of alpha1 -microglobulin (alpha1-m, protein HC) in an epidemiological study. METHODS: Urinary alpha1-m in 37 female inhabitants in a cadmium-polluted area, including seven cases with Itai-itai disease, and ten inhabitants in a non-polluted area in Japan were examined. The alpha1-m was measured by both the fluorometric ELISA and a commercially available enzyme immunoassay (EIA) method to evaluate correlation of the two measurements. Concentration of beta2-microglobulin (beta2-m) was also determined in the same samples. RESULTS: The detection limit of this method was 3 ng/ml or less of alpha1-m. A significant, high positive correlation was obtained between the alpha1-m concentrations measured with the fluorometric ELISA and that of EIA (r = 0.95, P < 0.0001). A significant association was also shown between the alpha1-m and beta2-m concentrations in the urine samples. The concentrations of urinary alphal-m of the inhabitants in the cadmium-polluted area (mean: 6.21 mg/l, 95% confidence interval (95% CI): 4.06-9.50 mg/l) were significantly higher than those of the reference area (mean: 2.19 mg/l, 95% CI: 1.90-2.67 mg/l). The urinary alpha1-m level of the Itai-itai patients was shown to be highest at 39.63 mg/l (95% CI: 28.27 55.55 mg/l). When the cut-off value of 10 mg/l was employed, alpha1-m had a sensitivity of 100% and specificity of 100% for Itai-itai disease. CONCLUSION: These results suggest that this fluorometric ELISA is a useful tool to determine urinary alpha1-m in the epidemiological survey of renal tubular dysfunction, especially in the cadmium-polluted area of Japan.

Aged↗

PubMed2001

Clinical significance of the serum surfactant protein D and KL-6 levels in patients with measles complicated by interstitial pneumonia.

UNLABELLED: To examine the value of surfactant protein D and KL-6 as markers for the diagnosis and the severity of interstitial pneumonia caused by measles infection, surfactant protein D, KL-6 and lactic acid dehydrogenase were measured serially in three patients with measles complicated by interstitial pneumonia as compared to ten measles infected patients without interstitial pneumonia. The serum surfactant protein D and KL-6 levels were higher in patients with measles and interstitial pneumonia as compared to those with measles without interstitial pneumonia. In patients with measles and interstitial pneumonia, the respiratory distress and the alveolar-arterial oxygen differences improved after steroid pulse therapy while the serum surfactant protein D level decreased dramatically under the cut-off level and earlier than the KL-6 level. On the contrary, the serum KL-6 level increased transiently and it took longer to decrease below the cut-off level as compared to the pattern observed for serum surfactant protein D. The serum lactic acid dehydrogenase level changes were between those of the surfactant protein D and KL-6 levels. CONCLUSION: Surfactant protein D and KL-6 are easily measured and useful markers for the diagnosis of interstitial pneumonia caused by measles infection. Early decrease of surfactant protein D contrasts with the transient increase of KL-6 levels after prednisolone pulse therapy.

Antigens↗

PubMed2001

Time-sequential changes in biomechanical and morphological properties of articular cartilage in cryopreserved osteochondral allografting.

This study examined time-sequential changes in the biomechanical and morphological properties of articular cartilage that had received cryopreserved osteochondral allografting. Osteochondral blocks obtained from the femurs of 18 rabbits were cryopreserved with dimethylsulfoxide (DMSO), using a two-step freezing method, and allografted to the femurs of another 18 rabbits. Specimens for biomechanical and morphological examinations were prepared at the second, fourth, and twelfth weeks after allografting (n = 18). In 12 allografted rabbits, biomechanical features were examined with an indentation test apparatus, and histological changes were studied with a light microscope (second week, n = 4; fourth week, n = 4; twelfth week, n = 4). In the other 6 allografted rabbits, cartilage surfaces were studied with a scanning electron microscope (second week, n = 2; fourth week, n = 2; twelfth week, n = 2). For controls, fresh, DMSO-treated, or DMSO-treated + cryopreserved specimens were examined biomechanically and morphologically. In the time-sequential examination of biomechanical features, both the parameter for elasticity (i.e., ratio of instant elastic strain to maximum strain) and the parameter for viscosity (i.e., average retardation time) significantly changed. Light microscopy showed chronological decreases in safranin-O staining intensity in the matrix, and progression of degeneration. On scanning electron microscopy, disruption of the cartilage surface was also recognized. Therefore, changes in biomechanical properties due to cryopreservation could cause irreversible changes in the cartilage in cryopreserved osteochondral allografting.

Animals↗

PubMed2001

Cationic polymer-mediated genetic transduction into cultured human chondrosarcoma-derived HCS-2/8 cells.

The usefulness of three types of cationic polymer, i.e., degraded polyamidoamine (PAMAM) dendrimer (SuperFect Transfection Reagent; Oiagen), linear polyethylenimine (PEI; ExGen 500; Euromedex), and branched PEI in gene delivery into chondrocytes was examined comparatively. A plasmid vector containing the Escherichia coli LacZ (pSES.beta) was combined with one of the three cationic polymers at various molar ratios and the resultant complex (polyplex) was used to transduce a human chondrocyte-like cell line, HCS-2/8. Gene expression was evaluated by an O-nitrophenyl beta-D-galactopyranoside (ONPG) assay and by staining with 0.05% 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-gal; Nacalai Tesque). The ONPG assay showed that the highest delivery rate was achieved when 2microg of pSES.beta was combined with either 21 microg of dendrimer, 1.7microg of linear PEI, or 2.0microg of branched PEI. At the same DNA/polymer ratios, the proportions of X-gal-stained cells were also the highest (31.3 +/- 7.5%, 30.3 +/- 9.0%, and 8.3 +/- 3.1%, respectively). LacZ expression reached the highest level 3 days after the dendrimer-mediated transduction, and gradually declined, returning to the background level on day 14. Possible cytotoxicity was examined by trypan blue staining and phase contrast microscopic observations. Neither cytotoxicity nor morphological change was induced at the optimal dose of each polymer. The cationic polymers, particularly the degraded dendrimer and linear PEI, would be a useful nonviral vector for gene delivery to cells of chondrocytes.

Bone Neoplasms↗

PubMed2001

The impact of chronic renal failure on atherosclerosis of the internal thoracic arteries.

BACKGROUND: Little is known about the impact of renal failure on atherosclerotic changes in the internal thoracic artery (ITA). METHODS: A total of 20 consecutive patients on chronic dialysis who underwent coronary artery bypass grafting (CABG) during April 1998 through September 1999 were investigated. The 20 control patients were selected from the same interval to rigorously match risk factors. Atherosclerosis of the ITA collected from each patient was analyzed using the subjective evaluation proposed by Kay and colleagues. RESULTS: There were no cases of greater than 25% atherosclerotic luminal narrowing among a total of 35 ITA specimens from dialysis patients. The degree of atherosclerosis was not significantly different from that of the specimens from matched patients (p = 0.18). No calcification was found in ITA grafts either microscopically or macroscopically. The number of elastic lamellae, an index of the elasticity of the ITA graft, was not significantly different from those obtained from the matched patients. Analysis of preoperative coronary angiography revealed that coronary calcification was significantly more frequent in dialysis patients (15 patients, 75%) than in matched patients (p < 0.05). By analysis of postoperative angiography in dialysis patients, no evidence of atherosclerotic changes was found in 28 opacified ITAs. In addition, despite the presence of calcification in the native coronary, no calcification was evident along the entire length of the ITAs. CONCLUSIONS: This study revealed the minimal impact of chronic renal failure on atherosclerotic changes in the ITA. The results of this study support the continued use of ITA grafting in dialysis patients.

Aged↗

PubMed2001

Technical aspects and outcome of in situ right internal thoracic artery grafting to the major branches of the circumflex artery via the transverse sinus.

BACKGROUND: Little is known about the anatomic limitations of in situ right internal thoracic artery (RITA) grafting to the circumflex artery. METHODS: To evaluate the technical aspects and outcome of revascularization of the proximal and distal major branches of the circumflex artery (obtuse marginal [OM] branch and posterolateral [PL] branch), a total of 145 patients who possessed a graftable branch of the circumflex artery were enrolled into the prospective project. There were 73 patients who had the PL branch as a primary target and 72 patients with OM branches, which were allocated by a blinded observer who reviewed the preoperative angiography. RESULTS: Changes of primary target vessels were required in 9 patients (6.2%), yielding an overall success rate of RITA grafting of 93.8%. The success rates of RITA grafting to the OM branch and the PL branch were 95.8% (69/72; CI 88.3% to 99.1%) and 91.7% (67/73; CI 83.0% to 96.9%), respectively. The univariate analysis identified grafting under hypothermic ventricular fibrillation as predictors of inability to use in situ RITA grafting for revascularization of the circumflex artery. RITA grafting to the PL branch is not identified as a predictor. Postoperative angiography in 136 patients revealed only one occlusion (0.75%) of the RITA graft anastomosed to the marginal artery. There were no significant differences in patency rates between left and right ITA grafts. CONCLUSIONS: This prospective study showed that in situ RITA was, in most cases, able to reach most branches of the major circumflex artery and demonstrated an excellent patency rate.

Adult↗

PubMed2001

Magnetic resonance imaging findings and postoperative neurologic dysfunction in elderly patients undergoing coronary artery bypass grafting.

BACKGROUND: Small cerebral infarctions are common in elderly patients, but the association between the magnetic resonance imaging finding and neurologic dysfunction after coronary artery bypass grafting has not been evaluated. METHODS: We determined, prospectively, whether varying degrees of abnormal findings on magnetic resonance images of the brain increased the incidence of preoperative cognitive decline, postoperative neuropsychological dysfunction, and stroke in 421 elderly patients (> or = 60 years) undergoing coronary artery bypass grafting. RESULTS: Control patients (almost normal or leukoaraiosis, n = 212) had rates of postoperative neuropsychological dysfunction (7%) and stroke (1.4%); the small infarctions group (some small infarctions, n = 126) had rates of 13% and 5.6%, respectively; whereas patients with multiple infarctions (multiple small infarctions or broad infarctions, n = 83) had rates of 20% and 8.4%, respectively (p = 0.004, p = 0.013). In the group with multiple infarctions, 49 patients (59%) were asymptomatic and 21 patients (25%) had cognitive decline. Stepwise logistic regression analysis demonstrated that the significant predictors of multiple small infarctions or large infarctions were history of cerebrovascular disease, renal insufficiency, cognitive decline, and cerebral arteriosclerosis. CONCLUSIONS: Multiple infarctions significantly increase the risk of neurologic dysfunction after coronary artery bypass grafting. Routine screening for preoperative cognitive decline should be performed to detect underlying ischemic cerebral disease in elderly patients.

Aged↗

PubMed2001

Prolonged inhibition of cholesterol synthesis by atorvastatin inhibits apo B-100 and triglyceride secretion from HepG2 cells.

Atorvastatin is a new HMG-CoA reductase inhibitor that strongly lowers plasma cholesterol and triglyceride (TG) levels in humans and animals. Since previous data indicated that atorvastatin has prolonged inhibition of hepatic cholesterol synthesis, we tested whether this longer duration of inhibitory effect on cholesterol synthesis decreased hepatic lipoprotein secretion in vitro. We used the HepG2 hepatoma cell line to: (1) determine the time required until levels of secreted apo B-100 and TG declined significantly, (2) examine the relation to the mass of cellular cholesteryl ester (CE) and (3) test microsomal triglyceride transfer protein (MTP) activity which leads to decreased apo B-100 production. Although atorvastatin significantly inhibited cholesterol synthesis in HepG2 cells regardless of treatment duration (1, 14 or 24 h), it did not inhibit TG synthesis. Apo B-100 and TG secretion were unchanged after 1-h atorvastatin treatment, but declined significantly after 24-h treatment. Atorvastatin treatment also reduced cellular CE mass, exhibiting both time- and dose-dependency. Mevalonolactone, a product of HMG-CoA reductase, attenuated the inhibitory effects of atorvastatin. Atorvastatin strongly reduced mRNA levels of MTP, whereas it did not inhibit MTP activity as measured by TG transfer assay between liposomes. Simvastatin also induced treatment- and time-dependent reductions in apo B-100, whereas the MTP inhibitor BMS-201038 exhibited no time dependency, instead inhibiting this variable even on 1-h treatment. These results indicate that reduced apo B-100 secretion caused by atorvastatin is a secondary result owing to decreased lipid availability, and that atorvastatin's efficacy depends on the duration of cholesterol synthesis inhibition in the liver.

Anticholesteremic Agents↗

PubMed2001

Triterpenoids from Adiantum caudatum.

Three triterpenoids, 8alpha-hydroxyfernan-25,7beta-olide, 3alpha-hydroxy-4alpha-methoxyfilicane and 19alpha-hydroxyferna-7,9(11)-diene were isolated from the fresh fronds of Adiantum caudatum. Their structures were elucidated by spectroscopic techniques. Thirteen known triterpenoids were also identified from this fern.

Ferns↗

PubMed2001

Dynamic endorectal magnetic resonance imaging for local staging and detection of neurovascular bundle involvement of prostate cancer: correlation with histopathologic results.

OBJECTIVES: To assess the staging accuracy and detection of neurovascular bundle involvement by dynamic subtraction contrast-enhanced endorectal magnetic resonance imaging (MRI) in patients with localized prostate cancer. METHODS: In 38 patients with biopsy-proven prostate cancer, endorectal MRI was performed on a 1.5-Tesla magnetic resonance system using the dynamic technique with gadolinium-diethylenetriaminepentaacetic acid bolus enhancement. Two radiologists prospectively assessed the tumor involvement, localization, capsular penetration, seminal vesicle invasion, and neurovascular bundle involvement. All patients subsequently underwent radical prostatectomy, and the MRI findings were correlated with the histopathologic results. RESULTS: The overall accuracy of detecting cancer localization in the prostate was 72%. The detection of involvement in the peripheral zone had an 80% accuracy rate, but for lesions in the transition zone, the rate was 63%. The sensitivity and specificity of tumor detection was 81% and 79% for peripheral zone cancers and 37% and 97% for transition zone cancers, respectively. The accuracy rate, was 84%, 97%, and 97% for the detection of capsular penetration, seminal vesicle invasion, and neurovascular bundle involvement, respectively. CONCLUSIONS: Prostatic MRI with an endorectal surface coil using the dynamic technique more accurately detected tumor localization, capsular penetration, seminal vesicle invasion, and neurovascular bundle involvement than previously reported methods. The detection of tumor localization was more accurate in the peripheral zone than in the transition zone. This technique may be useful for the selection of patients for radical prostatectomy and, particularly, for identifying candidates for nerve-sparing surgery.

Aged↗

PubMed2001

Microwave thermotherapy for benign prostatic hyperplasia with the Dornier Urowave: response durability and variables potentially predicting response.

OBJECTIVES: To evaluate the clinical efficacy and durability of transurethral microwave thermotherapy (TUMT) in the treatment of benign prostatic hyperplasia. The clinical variables useful in predicting outcome were identified. METHODS: From October 1996 to March 2000, 58 patients with symptomatic benign prostatic hyperplasia were treated with TUMT using the Urowave device. Treatment outcome was evaluated by the International Prostate Symptom Score (IPSS), quality-of-life assessment score, and urodynamic investigation. The patients were divided into those having a good and poor response on the basis of the degree of IPSS decrease at 3 months. RESULTS: The mean IPSS significantly decreased from 19.2 at baseline to 13.3 at 3 months (P <0.0001). The mean quality-of-life score changed from 4.6 at baseline to 2.9 at 3 months (P <0.0001). No statistically significant differences in peak flow rate, postvoid residual volume, Schäfer's obstruction scale, or detrusor pressure at peak flow were noted before or after TUMT. The pretreatment IPSS of the good response group was significantly higher than that of the poor response group (P=0.017). A more significant difference was obtained for the obstructive score (P = 0.002), and no difference was observed in the irritative score (P = 0.631). The Schäfer grading scale score of the good response group was significantly smaller than that of the poor response group (P = 0.047). CONCLUSIONS: TUMT with the Urowave was effective in eliminating symptoms associated with benign prostatic hyperplasia, but did not markedly improve the objective voiding parameters. Patients with urodynamically less obstructive symptoms but subjectively more obstructive symptoms are therefore probably good candidates for TUMT.

Aged↗

PubMed2001

Prediction of mechanical properties of healing fractures using acoustic emission.

The objective of this study was to develop a non-destructive method for monitoring fracture healing with acoustic emission (AE). Experimentally produced fractures of the rat femur were tested in tension and in torsion at 4, 6, 8 and 12 weeks after fracture. AE signals were monitored during these mechanical tests. The values for load and torque at the initiation of the AE signal were defined as new mechanical parameters. The apparent density and ash density of the fracture site were also measured at each time period. Tensile strength, tensile stiffness, maximum torque and torsional stiffness of the fracture site increased with time. The AE signal was detected before complete specimen failure. Load and torque for initiation of AE increased proportionally with increasing mechanical properties. The mineral density, however, reached a plateau at 8 weeks, when callus mechanical strength was approximately 50% of control. Load for initiation of AE was strongly correlated with the strength (r = 0.98), stiffness (r = 0.88), and failure strain (r = -0.63) of the callus. Torque for initiation of AE was highly correlated with the maximum torque (r = 0.95) and torsional stiffness (r= 0.93) of the callus. The findings of the present study indicated that some mechanical properties of healing fractures could be estimated by monitoring AE signals.

Acoustics↗

PubMed2001

Surgical repair of coronary arteriovenous fistula: a simple and useful approach to identify the fistulous communication.

In repairing coronary arteriovenous fistula (CAVF), it is very important to interrupt the fistulous tract without compromise of normal coronary vessel flow. In our case, selective coronary arteriography showed that the CAVF from the left anterior descending coronary artery (LAD) was very close to the native coronary artery and had a very broad and short neck. We describe a simple and useful approach, by using both antegrade and retrograde coronary perfusion, that makes it possible to certainly protect myocardium and to clearly distinguish the normal native coronary artery from the fistulous tract.

Aged↗

PubMed2001

Right gastric artery embolization to prevent acute gastric mucosal lesions in patients undergoing repeat hepatic arterial infusion chemotherapy.

PURPOSE: The purpose of the study was to investigate the technical outcome and clinical effect of right gastric artery (RGA) embolization to prevent acute gastric mucosal lesions caused by influx of anticancer agents into the RGA in patients undergoing repeat hepatic arterial infusion chemotherapy (HAIC). MATERIALS AND METHODS: In 217 patients with malignant hepatic tumors, we attempted RGA embolization with use of metallic coils and/or a mixture of n-butyl cyanoacrylate (n-BCA) and iodized oil, along with the embolization of the gastroduodenal artery. After this procedure, an infusion catheter was placed radiologically and HAIC was performed. We then evaluated the technical outcome and clinical effect of RGA embolization. RESULTS: RGA embolization was technically successful in 201 of 217 patients (93%). Major complications--nausea, epigastric pain, and fever--were noted in 12%, 4%, and 2% of successful cases, respectively, and were treated conservatively. Recanalization occurred in 4% (nine of 201) of the patients. Eventually, sufficient RGA embolization was achieved in 192 patients. The incidence of acute gastric mucosal lesions confirmed endoscopically was only 3% (five of 192) in patients with sufficient RGA embolization, whereas it was 36% (nine of 25) in patients without sufficient RGA embolization, with a significant difference (P <.01). CONCLUSION: RGA embolization is a highly feasible procedure that can reduce the incidence of acute gastric mucosal lesions associated with HAIC.

Acute Disease↗

PubMed2001

Biopsy of lung nodules with use of I-I device under intermittent CT fluoroscopic guidance: preliminary clinical study.

PURPOSE: To investigate the efficacy of computed tomography (CT) fluoroscopy and a new needle holder (the I-I device) in lung nodule biopsy. MATERIALS AND METHODS: The I-I device is made of acrylate resin and was used to keep the entire needle in the tomographic plane. This study consisted of biopsies of 79 lung nodules in 77 patients. The final diagnoses were malignant in 54 patients, benign in 23, and unconfirmed in two. The biopsy procedure time from the beginning of the CT fluoroscopy procedure to the removal of the needle was measured for 24 needle passes. The radiation dose on the physician's hand was measured in five cases with use of a thermoluminescence ring. RESULTS: Fifty-one malignant and 20 benign lesions were correctly diagnosed with histologic specimens (90%). In 58 of 77 patients (75%), the biopsy procedures were completed within a single breath-hold. Pneumothorax occurred in 20 of 77 patients (26%) and chest tube insertion was required in five. The incidence of pneumothorax was significantly lower in patients who held their breath during biopsy procedures compared with those who did not (P < .0001; chi2 test). The biopsy procedure time ranged from 15 to 39 seconds (mean: 28.2 sec). The mean radiation dose on the physician's hand was 2 mSv/case. CONCLUSION: The diagnostic accuracy of biopsy with use of the I-I device under CT fluoroscopic guidance is comparable with that of the conventional method; however, a combination of CT fluoroscopy and the I-I device enables rapid biopsy procedures.

Biopsy, Needle↗