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K Yano

Publications and source records attributed to K Yano.

At least 109 records · Page 6Linked to original sources

The effects of childhood residence in Japan and testing language on cognitive performance in late life among Japanese American men in Hawaii.

OBJECTIVES: To examine the association of years spent in Japan during childhood with cognitive test performance in late life among Japanese American men, and to assess the influence of the language used for testing on this association. DESIGN: A cross-sectional study. SETTING/PARTICIPANTS: A total of 3734 Japanese American men, aged 71-93 years, who were first- or second-generation migrants and living on Oahu Island, Hawaii. MEASUREMENTS: The outcome variable was cognitive test performance assessed using the Cognitive Abilities Screening Instrument (CASI), which was developed for cross-cultural studies of cognitive impairment. The explanatory variable of main interest was the number of years spent in Japan during school-age childhood years (ages 6-17). The associations of CASI scores with childhood years in Japan was evaluated using a stepwise multiple linear regression model in which a total of 40 potential confounders were included as covariates. RESULTS: In the total sample, there was an inverse association between CASI scores and middle childhood years in Japan. This association remained significant after controlling for age, education, socioeconomic status, traditional Japanese food consumption, pulmonary function, apolipoprotein E4, proficiency in speaking Japanese, and other possible confounders. When data were analyzed separately for subgroups according to the language preferred at testing (English or Japanese), associations between childhood years in Japan and CASI scores were in opposite directions negative for the group tested in English and positive for the group tested in Japanese. The interaction between the testing language and childhood years in Japan was statistically significant. CONCLUSIONS: There was an inverse association between years spent in Japan during school-age years of childhood and cognitive test performance in late life. This association could not be accounted for by age, education, or other confounding factors. However, this finding was not observed in participants who preferred being tested in Japanese. To assess cognitive test performance in older people, it is of prime importance to use the most optimal language for testing, usually the subject's native language.

Adolescent↗

Preserving normal ventricular activation versus atrioventricular delay optimization during pacing: the role of intrinsic atrioventricular conduction and pacing rate.

The purpose of the study was to compare the effects of DDD pacing with optimal AV delay and AAI pacing on the systolic and diastolic performance at rest in patients with prolonged intrinsic AV conduction (first-degree AV block). We studied 17 patients (8 men, aged 69 +/- 9 years) with dual chamber pacemakers implanted for sick sinus syndrome in 15 patients and paroxysmal high degree AV block in 2 patients. Aortic flow and mitral flow were evaluated using Doppler echocardiography. Study protocol included the determination of the optimal AV delay in the DDD mode and comparison between AAI and DDD with optimal AV delay for pacing rate 70/min and 90/min. Stimulus-R interval during AAI (ARI) was 282 +/- 68 ms for rate 70/min and 330 +/- 98 ms for rate 90/min (P < 0.01). The optimal AV delay was 159 +/- 22 ms. AV delay optimization resulted in an increase of an aortic flow time velocity integral (AFTVI) of 16% +/- 9%. At rate 70/min the patients with ARI < or = 270 ms had higher AFTVI in AAI than in DDD (0.214 +/- 0.05 m vs 0.196 +/- 0.05 m, P < 0.01), while the patients with ARI > 270 ms demonstrated greater AFTVI under DDD compared to AAI (0.192 +/- 0.03 m vs 0.166 +/- 0.02 m, P < 0.01). At rate 90/min AFTVI was higher during DDD than AAI (0.183 +/- 0.03 m vs 0.162 +/- 0.03 m, P < 0.01). Mitral flow time velocity integral (MFTVI) at rate 70/min was higher in DDD than in AAI (0.189 +/- 0.05 m vs 0.173 +/- 0.05 m, P < 0.01), while at rate 90/min the difference was not significant in favor of DDD (0.149 +/- 0.05 m vs 0.158 +/- 0.04 m). The results suggest that in patients with first-degree AV block the relative impact of DDD and AAI pacing modes on the systolic performance depends on the intrinsic AV conduction time and on pacing rate.

Aged↗

Two distinct inactivation processes related to phosphorylation in cardiac L-type Ca(2+) channel currents.

We investigated the inactivation process of macroscopic cardiac L-type Ca(2+) channel currents using the whole cell patch-clamp technique with Na(+) as the current carrier. The inactivation process of the inward currents carried by Na(+) through the channel consisted of two components >0 mV. The time constant of the faster inactivating component (30.6 +/- 2.2 ms at 0 mV) decreased with depolarization, but the time constant of the slower inactivating component (489 +/- 21 ms at 0 mV) was not significantly influenced by the membrane potential. The inactivation process in the presence of isoproterenol (100 nM) consisted of a single component (538 +/- 60 ms at 0 mV). A protein kinase inhibitor, H-89, decreased the currents and attenuated the effects of isoproterenol. In the presence of cAMP (500 microM), the inactivation process consisted of a single slow component. We propose that the faster inactivating component represents a kinetic of the dephosphorylated or partially phosphorylated channel, and phosphorylation converts the kinetics into one with a different voltage dependency.

Animals↗

Diurnal rhythms of luteinizing hormone, follicle-stimulating hormone, testosterone, and estradiol secretion before the onset of female puberty in short children.

To investigate hormonal changes before the onset of female puberty, we measured LH and FSH in serum samples drawn every 20 min for 24 h and measured testosterone and estradiol hourly for 24 h. Seventeen girls (13 prepubertal and 4 early pubertal) of short stature, from 5.1-11.4 yr of age, participated in this study. LH and FSH were measured using a time-resolved immunofluorometric assay, and testosterone and estradiol were measured using a sensitivity RIA capable of detecting testosterone and estradiol concentrations of 10 and 2 pg/mL, respectively. Diurnal rhythms of LH, FSH, and testosterone were apparent in all subjects, including those aged 5-6 yr. Serum LH and FSH concentrations showed night-day variation in a pulsatile fashion. The serum testosterone concentration was elevated in the early morning in all subjects. The serum estradiol concentration was elevated in the early morning in 4 of 13 prepubertal subjects and all 4 early pubertal subjects. The diurnal pattern of the serum estradiol concentration was similar to that of the serum testosterone concentration. Mean 24-h LH and testosterone concentrations in prepubertal subjects who did not attain puberty for at least 1 yr were 0.07 U/L and 65 pg/mL, respectively, whereas those in prepubertal subjects who attained puberty within 1 yr (0.14 U/L and 106 pg/mL, respectively) were significantly higher. Furthermore, mean 24-h LH, FSH, testosterone, and estradiol concentrations increased with the onset of puberty. In conclusion, the diurnal rhythms of LH, FSH, and testosterone already exist at 5-6 yr of age, and serum LH and testosterone levels increase before the onset of puberty. These results suggest that preparation for the onset of female puberty may begin in 5- to 6-yr-old girls.

Aging↗

Identification of protein disulfide isomerase as a phorbol ester-binding protein.

A specific binding protein for 12-O-tetradecanoylphorbol 13-acetate (TPA), different from protein kinase C (PKC) and histone H1, was purified from HeLa cell extract by the use of affinity gel pendanted with phorbol ester (TPA-GEL). The purified binding protein was identified as protein disulfide isomerase (PDI, EC 5.4.3.1) by peptide sequence analysis. The dissociation constants (Kd's) of TPA to PDI, histone H1 and PKCalpha were determined to be 1.03 x 10(-6) M, 5.70 x 10(-7) M, and 4.00 x 10(-7) m, respectively, by the surface plasmon resonance (SPR) method. TPA moderately inhibited PDI activity assessed in terms of reactivation of denatured RNase A.

Amino Acid Sequence↗

Radiofrequency catheter ablation of a concealed atrioventricular accessory pathway associated with a coronary sinus diverticulum.

A 31-year-old woman underwent radiofrequency catheter ablation of a concealed left posteroseptal accessory pathway associated with a coronary sinus diverticulum. The patient had previously undergone unsuccessful catheter ablation of the posteroseptal region of the mitral annulus. Coronary sinus venography revealed the presence of the diverticulum near the ostium. An electrogram in the neck of the diverticulum showed the shortest ventriculoatrial conduction time and a large accessory pathway potential during atrioventricular reciprocating tachycardia. The pathway was successfully ablated within the neck of the diverticulum. The findings in this case underscore the importance of coronary sinus venography before ablation.

Adult↗

Clinical characteristics of female patients with coronary spastic angina: comparison with male patients.

There are many patients with vasospastic angina who have minor atherosclerosis, and in Japan the majority of them are male. No data exist concerning sex differences in patients with coronary spastic angina, so the present study sought to clarify the clinical characteristics between male and female patients with vasospastic angina. Between April 1991 and June 1998, 204 consecutive patients were diagnosed with vasospastic angina and of these, 26 (12.7%) were female. An acetylcholine test was performed with incremental doses of 20, 50, and 80 microg injected into the right coronary artery and 20, 50, and 100 microg into the left coronary artery. Ergonovine was injected in a total dose of 40 microg into the right coronary artery and 64 microg into the left coronary artery. Coronary spasm was defined as 99% or more luminal narrowing accompanied by ischemic changes on ECG. Compared with male patients, female patients had less organic stenosis (12 vs 33%, p<0.05), less history of smoking (15 vs 85%, p<0.01), and fewer focal spasms (31 vs 64%, p<0.01). There were no other differences between the 2 groups. In conclusion, Japanese female patients with vasospastic angina had the characteristics of diffuse provoked spasm, less organic stenosis, and less history of smoking, but only 1 in 10 of all patients with vasospastic angina are female.

Aged↗

New combined spasm provocation test in patients with rest angina: intracoronary injection of acetylcholine after intracoronary administration of ergonovine.

The incidence of provoked coronary spasm with the standard single spasm provocation test has been relatively low in patients with rest angina. The present study examined the clinical usefulness of a newly designed spasm provocation test, an intracoronary injection of acetylcholine (ACh) following an ergonovine (ER) test, in patients with rest angina who demonstrated low disease activity and atypical chest pain. Triple sequential spasm provocation tests were performed in 24 patients with atypical chest pain who had no ischemia and in 40 patients with rest angina who had distinct ischemia. Initially, an ACh test (20-100 microg) and then an ER test (40-64 microg) were performed and then, if no spasm was provoked, an intracoronary injection of ACh was given after the ER test to evaluate coronary spasm. Coronary spasm was defined as total or subtotal occlusion. In the 24 patients with atypical chest pain, no spasm was provoked by intracoronary injection of either ACh or ER, but coronary spasms were induced in 2 patients using the new method, with the remaining 22 not experiencing spasm (specificity of new method, 92%). In the 40 patients with rest angina, intracoronary injection of ACh induced coronary spasm in 22 patients (group I) and 6 (group II) demonstrated spasm with intracoronary injection of ER. Coronary spasm was not induced by either the ACh test or the ER test in 12 patients (group III). The intracoronary administration of ACh after the ER test provoked spasm in 11 of 12 patients. Diffuse spasms were provoked in 10 of 11 patients. In patients with rest angina, the frequency of chest pain attacks in 1 month experienced by patients in group III (0.8+/-0.8) was significantly lower than that of patients in group I (7.0+/-5.3, p<0.01) or II (3.5+/-2.3, p<0.05). No serious or irreversible complications related to this new combined method were observed. In conclusion, this method was safe and reliable for the induction of coronary spasm in patients with rest angina who may have low disease activity.

Acetylcholine↗

Riedel's lobe of the liver evaluated by multiple imaging modalities.

An 81-year-old Japanese woman visited our hospital because of abdominal discomfort. Physical examination revealed that she had an abdominal mass. A combination of ultrasonography, computed tomography, magnetic resonance imaging (MRI), and hepatic asialoglycoprotein scintigraphy was utilized to make a diagnosis. We found that she had a downward elongated hepatic lobe or Riedel's lobe which did not appear to be common in our district. The prevalence of Riedel's lobe in the Asian population has not been studied. Furthermore, this is the first report that describes the MRI and hepatic asialoglycoprotein scintigraphy features of Riedel's lobe of the liver.

Abdominal Pain↗

Left ventricular aneurysm without coronary artery disease, incidence and clinical features: clinical analysis of 11 cases.

OBJECTIVE: To examine the incidence, underlying disease and clinical features of left ventricular aneurysm (LVA) not related to coronary artery occlusion. METHODS: Retrospective review of consecutive patients who underwent both left ventriculography and coronary angiography. PATIENTS: LVA was confirmed in 11 of 2,348 consecutive patients (0.47%). RESULTS: The location of LVA was mainly in the apical region (81.8%). In five of the 11 patients (45.5%), the underlying heart disease was hypertrophic cardiomyopathy (HCM), including 4 patients of dilated phase and one patient of midventricular type. The serial ECG changes from left ventricular hypertrophy to abnormal Q wave and endomyocardial biopsy were useful for the differential diagnosis of these cases against myocardial infarction. The underlying disease of the remaining patients was: myocarditis (2 patients), arrhythmogenic right ventricular dysplasia (1 patient), Chagas' disease (1 patient), glycogen storage disease (1 patient), and sarcoidosis (1 patient). Ventricular tachycardia appeared in 9 of 11 cases (81.8%) including 2 patients with sustained ventricular tachycardia. CONCLUSION: LVA formation without coronary artery disease was a rare phenomenon. The underlying disease was varied but the incidence of hypertrophic cardiomyopathy in the dilated phase was comparatively high. Ventricular tachycardia was a significant complication in these patients.

Adult↗

A fatal case of fulminant myocarditis with human herpesvirus-6 infection.

We report a case of fulminant myocarditis after steroid pulse therapy for acute hepatitis. Serological studies demonstrated a four-fold increase in the antibodies against human herpesvirus-6 (HHV-6) IgG, and a PCR showed the existence of HHV-6 virus DNA. HHV-6 virus DNA was also isolated from the liver and the heart. We believe that exacerbation of fulminant myocarditis was probably associated with the reactivation of HHV-6 due to the immunosuppressive state of the host.

Antibodies, Viral↗

Quality of life in adult patients after stem cell transplantation.

Many articles pertaining to quality of life (QOL) following stem cell transplantation have been published in the US and western Europe. However, since the actions of health insurance systems and overall cultural aspects are strongly associated with QOL, investigations into QOL should be carried out within all countries. Therefore, we have investigated the QOL of adult patients following stem cell transplantation at 31 hospitals in Japan. The survivors, who were surveyed by mail questionnaire, were 20 years or older at the time of this study. The underlying diseases were acute lymphoblastic leukemia, acute myelogenous leukemia, chronic myelogenous leukemia, non-Hodgkin's lymphoma, Hodgkin's disease, myelodysplastic syndrome, and multiple myeloma. Median age at the time of the study was 36 years, and median interval after transplantation was 35.3 months. Of 383 patients surveyed, 282 (73.6%) responded to the questionnaire. One hundred and ninety-two patients were treated with an allogeneic-related transplantation, 52 with allogeneic-unrelated, and 38 with an autologous transplantation. Our data revealed that the length of time since transplantation and the diagnosis of chronic GVHD were associated with QOL. When unrelated and related transplantation recipients were compared, ratings on relief from pain, stability in weight, and confidence in dealing with daily life were lower among unrelated transplantation patients.

Adolescent↗

Effective and safe interferon treatment for Japanese patients with chronic myelogenous leukemia relapse after bone marrow transplantation. The Nagoya Blood and Marrow Transplantation Group.

The purpose of this study was to assess the efficacy and safety of interferon (IFN) treatment in patients with a relapse of chronic myelogenous leukemia (CML) after bone marrow transplantation in Japan. Accordingly, we retrospectively analyzed the results obtained from 8 patients treated with IFN by the Nagoya Blood and Marrow Transplantation Group. One of 3 patients with hematologic relapse and all 5 patients with cytogenetic relapse achieved complete cytogenetic response (CCR). The median time to achieve CCR was 8 months (range, 3-16 months). One patient relapsed 9 months after starting IFN and died of blast crisis. CCR was maintained for a median duration of 47 months (range, 9-79 months) in the remaining 5 patients. The median duration of survival of these 5 patients after starting IFN was 58 months (range, 12-89 months). At the time of this report, 2 patients who did not attain CCR have survived for 81 months and 142 months after starting IFN, respectively. During IFN treatment, 1 patient showed a transient deterioration of chronic graft-versus-host disease, and no treatment-related deaths were observed. These results suggest that treatment with IFN for CML patients who relapse after bone marrow transplantation is effective and safe. A prospective study to compare IFN with donor lymphocyte infusion is necessary to establish the optimal strategy for the treatment of CML patients who relapse after bone marrow transplantation.

Adult↗

Interaction between a Solute Molecule and a Fluorocarbon Bonded Layer in Reversed-Phase High-Performance Liquid Chromatography.

Glassesand silica-gel packings modified with fluorocarbon and hydrocarbon silylation agents were prepared to investigate the separation mechanism of a fluorocarbon bonded layer in reversed-phase high-performance liquid chromatography (RP-HPLC). On the hydrocarbon layer the contact angles of benzene (Be) and hexafluorobenzene (FB) decreased with increasing carbon chain length of the modifier, and the mobile phase (MP) was independent of the modifier. The fluorocarbon layer gave a larger contact angle for each liquid than the hydrocarbon layer. The retention factor, k, of Be and FB on hydrocarbon packings increased with decreasing contact angle. It was demonstrated that the separation of Be and FB on hydrocarbon packings is caused by solvophobic interaction between solute molecules and the stationary layer. In contrast, k increased with increasing contact angle at the fluorocarbon layer. The retention of Be and FB on fluorocarbon packings may be attributed to the penetration of the solute molecules from the mobile phase into the fluorocarbon stationary layer. Copyright 1999 Academic Press.

Journal Article↗

Characterization of a duocarmycin-DNA adduct-recognizing protein in cancer cells.

Duocarmycins have been reported to derive their potent antitumor activity through a sequence-selective minor groove alkylation of N3 adenine in double-stranded DNA. We have used gel mobility shift assays to detect proteins that bind to DNA treated in vitro with duocarmycin SA and identified a protein, named duocarmycin-DNA adduct recognizing protein (DARP), which binds with increased affinity to duocarmycin-damaged DNA. Examination with partially purified DARP revealed that the protein recognized not only the DNA adduct of structurally related drug, CC-1065, but unexpectedly, the protein also recognized the DNA adduct of another chemotype of minor groove binder, anthramycin. These results demonstrate that DARP recognizes the structural alteration of DNA induced by these potent DNA-alkylating drugs, suggesting the possibility that the protein might modulate the antitumor activity of these drugs.

Animals↗