A review of the microtremor horizontal-to-vertical spectral ratio (MHVSR) method

The single-station microtremor horizontal-to-vertical spectral ratio (MHVSR) method was initially proposed to retrieve the site amplification function and its resonance frequencies produced by unconsolidated sediments overlying high-velocity bedrock. Presently, MHVSR measurements are predominantly conducted to obtain an estimate of the fundamental site frequency at sites where a strong subsurface impedance contrast exists. Of the earthquake site characterization methods presented in this special issue, the MHVSR method is the furthest behind in terms of consensus towards standardized guidelines and commercial use. The greatest challenges to an international standardization of MHVSR acquisition and analysis are (1) the what - the underlying composition of the microtremor wavefield is site-dependent, and thus, the appropriate theoretical (forward) model for inversion is still debated; and (2) the how - many factors and options are involved in the data acquisition, processing, and interpretation stages. This paper reviews briefly a historical development of the MHVSR technique and the physical basis of an MHVSR (the what). We then summarize recommendations for MHVSR acquisition and analysis (the how). Specific sections address MHVSR interpretation and uncertainty assessment.

The use of angiotensin receptor blockers is associated with greater recovery of cardiac function than angiotensin-converting-enzyme inhibitors among patients with dilated cardiomyopathy

Background

We previously showed that angiotensin-converting-enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB) were associated with heart failure with recovered ejection fraction (HFrecEF) in patients with dilated cardiomyopathy (DCM). However, the different effects of these drugs on cardiac reverse remodeling have not been fully elucidated. The aim of this study was to assess comparative effectiveness of ACEi versus ARB on recovery of left ventricular ejection fraction (LVEF) among patients with DCM.

Methods

We analyzed the clinical personal records of DCM, a national database of Japanese Ministry of Health, Labour and Welfare, from 2003 to 2014. Patients with LVEF <40% and on either ACEi or ARB were included. Eligible patients were divided into two groups according to the use of ACEi or ARB. A one-to-one propensity case-matched analysis was used. A propensity score was estimated by fitting a logistic-regression model which adjusted for age, sex, duration of HF, NYHA functional class (I-II vs. III-IV), systolic blood pressure, diastolic blood pressure, heart rate, atrial fibrillation, pacing, left bundle branch block, LVEF, hypertension, diabetes mellitus, hyperuricemia, chronic kidney disease, B-type natriuretic peptide (BNP), beta-blockers, mineralocorticoid receptor antagonists, loop diuretics, thiazides, digitalis, amiodarone, and oral inotropes. The primary outcome was defined as LVEF ≥40% at 3 years of follow-up.

Results

Out of 4,618 eligible patients, 2,238 patients received ACEi and 2,380 patients received ARB. Propensity score matching yielded 1,341 pairs. Mean age was 56.0 years and 2,041 (76.1%) was male. Mean LVEF was 27.6%, and median duration of HF was 1 year. The primary outcome was observed more frequently in ARB group than in ACEi group (59.8% vs. 54.1%; odds ratio [OR] 1.26; 95% confidence interval [CI] 1.08–1.47; P=0.003). The change in LVEF from baseline to 3 years of follow-up was greater in ARB group than in ACEi group (15.8±0.4 vs. 14.0±0.4%, P=0.002). In the ACEi group, 946 patients (70.6%) continued to receive ACEi at 3 years of follow-up, while 1,088 patients (81.3%) continued to receive ARB in the ARB group. Per-protocol analysis consistently showed that ARB increased the prevalence of HFrecEF (62.0% vs. 54.0%; OR 1.39; 95% CI 1.17–1.66; P<0.001). Subgroup analysis showed that ARB increased frequency of HFrecEF regardless systolic blood pressure, heart rate, LVEF, chronic kidney disease, and concomitant use of beta-blockers and mineralocorticoid receptor antagonists.

Conclusions

The use of ARB was associated with HFrecEF more frequently than ACEi among patients with DCM and reduced LVEF.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Health Sciences Research Grants from the Japanese Ministry of Health, Labour and Welfare (Comprehensive Research on Cardiovascular Diseases)Japan Agency for Medical Research and Development (AMED) grant

Cyclin dependent kinase 1 (CDK1) positively regulates cardiac hypertrophy and fibrosis via TGF-beta pathway

Background

Transforming growth factor beta (TGF-β) critically mediates cardiac fibrosis by transforming fibroblasts to myofibroblasts in pathological conditions. Cyclin dependent kinases (CDKs), cell cycle-regulating proteins, are known to be intimately involved in cardiac fibrosis. Among CDK isoforms, CDK1 is essential for cell cycle progression and cell division. It is reported some interphase CDKs such as CDK4 or CDK6 were involved in cardiac fibrosis, however, detailed mechanisms of cardiac fibrosis through CDK1 and its interactions with TGF-β in cardiac fibrotic process haven't been elucidated. We hypothesize that CDK1 is involved in cardiac fibrotic process via TGF-β pathway and its suppression decreases TGF-β expression and transformation to myofibroblasts from fibroblasts presenting antifibrotic effect.

Methods and results

Isolated neonatal rat cardiac fibroblasts were treated with angiotensin II (ANG II, 1 μM, 24 h) or phosphate-buffered saline (PBS). ANG II increased CDK1 and TGF-β in cardiac fibroblasts, by 97% and 292%, respectively (p<0.05). Administration of Ro-3306, a specific CDK1 inhibitor (1 μM, 24 h), suppressed TGF-β protein levels in ANG II-treated cardiac fibroblasts by 58% (p<0.05). Similarly, knockdown of CDK1 by RNA silencing also inhibited ANG II-induced increases in TGF-β in cardiac fibroblasts by 39% (p<0.05). ANG II increased alpha-smooth muscle actin (α-SMA), which is a marker of myofibroblasts, and knockdown of CDK1 significantly suppressed it by 49% (p<0.05). In vivo study, 11-week-old male C57BL/6J mice were administered ANG II continuously with infusion pump, at a dose of 1000 ng/kg/min, for a week. Also, Ro-3306 was intraperitoneally injected at a dose of 2 mg/kg/day, every other day, for a week. First, Ro-3306 attenuated ANG II-mediated cardiac hypertrophy indicated by heart weight and echocardiographic parameter as to left ventricular wall thickness. Second, CDK1 and TGF-β expression were significantly augmented in ANG II-infused mice by 404% and 113%, respectively (p<0.05). Injection of Ro-3306 suppressed TGF-β protein levels by 48%, although the difference wasn't statistically significant (p=0.09). Finally, histopathological examination (Masson's trichrome stain) demonstrated remarkable repression of ANG II-induced cardiac fibrosis by Ro-3306.

Conclusions

CDK1 positively controls cardiac fibrotic process by regulating transformation to cardiac myofibroblasts from fibroblasts via TGF-β pathway. It also presents an antihypertrophic effect on ANG II stimulation. CDK1 is a potential therapeutic target of cardiac fibrosis and hypertrophy.

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): KAKENHI

The nationwide registry of hospitalized heart failure patients in Japan: Japanese Registry Of Acute Decompensated Heart Failure (JROADHF)

Background and aim

Heart failure (HF) is a growing healthcare problem worldwide. This study aimed to describe clinical characteristics and long-term outcomes of HF patients in Japan.

Methods and results

JROADHF (the Japanese Registry Of Acute Decompensated Heart Failure) is a retrospective, multicentre, nationwide observational database of 13,238 patients hospitalized due to HF in 128 hospitals randomly selected from Japanese Circulation Society (JCS)-certified teaching hospitals during 2013. At inclusion, demographic and clinical data were collected from medical records with linkage to a nationwide claim-based database, the Japanese Diagnosis Procedure Combination (DPC). Patients were followed up to 5 years after discharge at each participating site. Patients were old as the median age of 81 years and women were older (74.8±12.8 vs 81.6±11.1 y.o). Mean left ventricular ejection fraction (LVEF) was 47%, and 45% were HF with preserved ejection fraction of >50% (HFpEF). Causes of HF included ischemic in 27%, valvular in 19%, arrhythmia in 17%, and hypertensive in 16%. Median length of hospital stay was 18 days and in-hospital mortality was 7.7%. All-cause mortality during 1 and 4 years were 22.3% and 48.4%, respectively. Hospitalization rates due to HF within 1 and 4 years were as high as 30.5 and 48.4%, respectively.

Conclusions

Contemporary nationwide registry revealed that hospitalized HF patients were elder and had more HFpEF, and their prognosis was still poor compared to the data shown in prior registries.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Japan Agency for Medical Research and Development (AMED) Practical Research Project for Life-Style related Diseases including Cardiovascular Diseases and Diabetes Mellitus

Use of direct oral anticoagulants is associated with better long-term outcomes in patients with atrial fibrillation and heart failure as compared with vitamin K antagonists

Background

Direct oral anticoagulants (DOACs) have been shown to be safe and effective in patients with atrial fibrillation (AF) as compared with warfarin, a vitamin K antagonist. However, the safety and efficacy of DOACs in patients with AF and heart failure (HF) have been unclear.

Purpose

The purpose of this study was to determine whether DOACs can improve long-term outcomes in patients with AF and HF as compared with warfarin.

Methods

We analyzed the JROADHF registry, which was a multicenter registry of patients hospitalized for the worsening HF in Japan. Baseline data were collected during the episode of index hospitalization from April 2013 to March 2014. Follow-up data were collected up to 4.5 years after the index hospitalization. Patients with AF and creatinine clearance ≥15 ml/min/1.73m2 were included. Valvular heart disease, congenital heart disease, and constrictive pericarditis were excluded. Eligible patients were divided into two groups according to the use of warfarin or DOACs. The primary outcome was defined as all-cause death. The secondary outcomes were defined as cardiovascular death, composite of all-cause death or cardiovascular hospitalization, and composite of stroke death or stroke related hospitalization. A one to one propensity case-matched analysis was used. Complete case analysis and multiple imputation analysis were also conducted as sensitivity analyses.

Results

Out of the 14,847 patients in this registry, 2,175 had AF, creatinine clearance ≥15 ml/min/1.73m2 and discharged alive. Propensity score matching yielded 475 pairs. In matching cohort, mean age was 76.5 years and 513 (54.0%) was male. Mean left ventricular ejection fraction was 48.6±16.4%. During a mean follow-up of 3.2 years, patients with DOACs had a lower incidence rate of all-cause death than those with warfarin (75.2 vs. 99.9 death per 1000 patient-years; rate ratio (RR) 0.75; 95% confidence interval [CI] 0.59–0.96; P=0.022). The incidence of cardiovascular death tended to be lower in DOAC group (30.9 vs. 43.1; incidence rate ratio 0.72; 95% CI 0.49–1.04; P=0.081). There were no significant differences in the incidence of composite of all cause death or cardiovascular hospitalization (252.3 vs. 269.4; RR 0.94; 95% CI 0.79–1.11; P=0.45) or composite of stroke death or stroke related hospitalization (13.1 vs. 16.7; RR 0.79; 95% CI 0.39–1.59; P=0.50). Cox regression model showed that DOAC was associated with lower mortality than warfarin (hazard ratio (HR) 0.75; 95% CI 0.59–0.96; P=0.023). Complete case analysis (HR 0.78; 95% CI 0.63–0.98; P=0.035) and multiple imputation analysis (HR 0.78; 95% CI 0.68–0.84; P<0.001) also showed the same results. A restricted cubic spline analysis demonstrated that the effectiveness of DOACs over warfarin waned with age, and DOACs were effective in patients younger than 80 years old.

Conclusion

Use of DOACs was associated with better long-term outcome in patients with HF as compared with warfarin.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Japan Agency for Medical Research and Development

Prognostic value of cardiac 123I-metaiodobenzylguanidine imaging for predicting cardiac events after transcatheter aortic valve replacement

Background

In patients with aortic valve stenosis (AS), cardiac sympathetic nervous (CSN) dysfunction and its improvement after TAVR have been reported; however, the prognostic impact of CSN function remains unclear. This study investigated the prognostic value of cardiac 123I-metaiodobenzylguanidine (MIBG) imaging for the prediction of cardiac events after transcatheter aortic valve replacement (TAVR).

Methods

This study was a single-center prospective observational study that enrolled patients with AS or failed surgical bioprostheses between July 2017 and May 2019. MIBG scintigraphy was performed before and after TAVR to evaluate the delayed heart–mediastinum ratio (d-H/M). Patients were classified into three pairs of groups based on the baseline and post-TAVR d-H/M (≥2.0 or <2.0) and on the presence of TAVR-related improvement of d-H/M. The study endpoints were major adverse cardiac events (MACE), including all-cause death, myocardial infarction, and hospitalization due to heart failure. The association of d-H/M with MACE following TAVR was based on a Cox proportional hazards ratio model adjusted for multiple prognostic variables.

Results

Of 187 consecutive patients who underwent TAVR, 111 (31 men; median age: 86 years) were evaluated. Over a median follow-up of 366 days, 16 (14.4%) patients had MACE. The incidence of MACE was significantly lower in patients with d-H/M improvement and/or the high post-TAVR d-H/M (≥2.0). Post-TAVR d-H/M had significant impacts on MACE, with an adjusted hazard ratio of 1.326 (95% confidence interval, 0.139–2.515; p=0.027).

Conclusions

Both d-H/M improvement and high post-TAVR d-H/M were associated with better prognosis in patients who underwent TAVR. Cardiac MIBG imaging was useful for predicting cardiac events after TAVR.

Funding Acknowledgement

Type of funding source: None

Artificial intelligence-based analysis of payment system data can predict one-year mortality of hospitalized patients with heart failure

Background

Individual risk stratification is fundamental in the care of heart failure (HF) patients. However, the prediction performance of risk scores, such as MAGGIC and SHFM, is not adequate and, more importantly, they need additional predictors including various biomarkers, imaging data, and environmental factors. Data from a case-mix payment system including diagnosis and procedures with outcomes can be used to develop the risk prediction models, allowing the use of big data for a more accurate prediction of mortality.

Purpose

This study aimed to develop artificial intelligence (AI) models for predicting 1-year mortality in patients hospitalized due to HF.

Methods

We analyzed the data from 10175 patients enrolled in the Japanese Registry Of Acute Decompensated Heart Failure (JROADHF). Candidate variables included the data obtained from a payment system introduced by the Japanese government, the Diagnosis Procedure Combination (DPC), which included each patient profile (age, sex, height, weight), principal diagnosis for hospitalization, comorbidities, procedures, length of hospital stay, and discharge status. They did not include clinical data available from patients such as vital status, laboratory data including bio-makers, electrocardiographic and echocardiographic data. The collected data were divided into the training set and the validation set (80%: 20%). With the training set, 5 AI models (logistic regression, random forest, support vector machine, neural network, and ensemble classifier) learned the one-year mortality results. AI models were evaluated by using the validation set with ROC analysis. The training and validation steps were repeated 10 times with different seed values to calculate the C-statistic of each model. We also identified the predictors for one-year prognosis acquired from the AI models.

Results

At 1-year of follow-up, a total of 1727 patients had died (17%). Among the machine learning models, the ensemble classifier showed the highest C-statistic of 0.76 (95% confidence interval: 0.75 to 0.77) for predicting mortality. Top predictors acquired from the random forest classifier was ADL (Barthel Index) at discharge, age, body mass index, and length of hospital stay.

Conclusion

By using AI-based analysis of a national case-mix payment system data, the present risk stratification model could predict the one-year mortality of hospitalized HF patients without any quantitative laboratory and physiological data. Furthermore, the present results could emphasize the advantage of this approach using the claim-based data that are routinely collected in a usual daily practice with no need to collect any additional information.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Japan Agency for Medical Research and Development

Beta-blocker use is associated with prevention of left ventricular remodeling in recovered dilated cardiomyopathy

Background

Withdrawal of optimal medical therapy has been reported to relapse cardiac dysfunction in patients with dilated cardiomyopathy (DCM) whose cardiac function had improved. However, it is unknown whether beta-blockers can prevent deterioration of cardiac function in those patients.

Purpose

We examined the effect of beta-blockers on left ventricular ejection fraction (LVEF) in recovered DCM.

Methods

We analyzed the clinical personal records of DCM, a national database of Japanese Ministry of Health, Labor and Welfare, between 2003 and 2014. Recovered DCM was defined as a previously documented LVEF <40% and a current LVEF ≥40%. Patients with recovered DCM were divided into two groups according to the use of beta-blockers. The primary outcome was defined as a decrease in LVEF >10% at two years of follow-up. A one to one propensity case-matched analysis was used. A per-protocol analysis was also performed. Considering intra- and inter-observer variability of echocardiographic evaluations, we also examined outcomes by multivariable logistic regression model after changing the inclusion criteria as follows; (1) previous LVEF <40% and current LVEF ≥40%; (2) previous LVEF <35% and current LVEF ≥40%; (3) previous LVEF <30% and current LVEF ≥40%; (4) previous LVEF <40% and current LVEF ≥50%. Outcomes were also changed as (1) decrease in LVEF ≥5% (2) decrease in LVEF ≥10% (3) decrease in LVEF ≥15%. The analysis of outcomes by using combination of multiple imputation and inverse probability of treatment weighting was also conducted to assess the effects of missing data and selection bias attributable to propensity score matching on outcomes.

Results

From 2003 to 2014, 40,794 consecutive patients with DCM were screened. Out of 5,338 eligible patients, 4,078 received beta-blockers. Propensity score matching yielded 998 pairs. Mean age was 61.7 years and 1,497 (75.0%) was male. Mean LVEF was 49.1±8.1%. The primary outcome was observed less frequently in beta-blocker group than in no beta-blocker group (18.0% vs. 23.5%; odds ratio [OR] 0.72; 95% confidence interval [CI] 0.58–0.89; P=0.003). The prevalence of increases in LVDd (11.5% vs. 15.8%; OR 0.70; 95% CI 0.54–0.91; P=0.007) and LVDs (23.1% vs. 27.2%; OR 0.80; 95% CI 0.65–0.99; P=0.041) was also lower in the beta-blocker group. Similar results were obtained in per-protocol analysis. These results were robust to several sensitivity analyses. As a result of preventing a decrease in LVEF, the deterioration to HFrEF was also prevented by the use of beta-blocker (23.6% vs. 30.6%). Subgroup analysis demonstrated that beta-blocker prevented decrease in LVEF regardless of atrial fibrillation.

Conclusion

Use of beta-blocker was associated with prevention of decrease in left ventricular ejection fraction in patients with recovered DCM.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Health Sciences Research Grants from the Japanese Ministry of Health, Labour and Welfare (Comprehensive Research on Cardiovascular Diseases)

P6283Downregulation of Tim44 exacerbates oxidative stress-induced ROS production and cardiomyocytes death by reducing mitochondrial SOD2

Background

Mitochondrial dysfunction has been highlighted as a critical driver of cardiac remodeling and failure. Mitochondria contains about 1500 proteins, 99% of which are encoded in the nuclear genome. Therefore, protein import into mitochondria is essential to maintain mitochondrial function. Previous reports suggest that nuclear-encoded mitochondrial precursor proteins import into mitochondria by multiple complex; translocase of outer membrane (TOM), translocase of inner membrane (TIM), and protein associated motor (PAM). However, the role of these protein import machineries of mitochondria in cardiac remodeling remains to be elucidated.

Objective

The purpose of this study was to elucidate the role of TOM, TIM, and PAM complex in cardiac remodeling and cardiomyocyte death.

Methods and results

C57BL/6J mice were subjected to myocardial infarction (MI) by permanent ligation of left anterior descending artery. Four weeks after operation, MI-mice demonstrated left ventricular (LV) dilation (LV end-diastolic dimension: 3.91 vs. 5.54 mm, n=8–11, p<0.05) and dysfunction (LV fractional shortening: 33.3 vs. 7.7%, n=8–11, p<0.05). Tim44 protein levels, a component of PAM complex, in mitochondrial fraction from non-infarcted left ventricle were significantly decreased compared with those in the heart from sham-operated mice by 39% (p<0.05), whereas other proteins related to TOM, TIM and PAM complex such as Tom20, Tom22, Tom40, Tom70, Tim22, Tim23 and mtHSP70 were not altered between MI-mice and sham-mice. In addition, blue-native polyacrylamide gel electrophoresis revealed that a protein complex associated to Tim44 was significantly decreased in non-infarcted LV by 40% (p<0.05). Superoxide dismutase 2 (SOD2), a mitochondrial matrix protein, was decreased in mitochondrial fraction from non-infarcted LV by 20% (p<0.05), accompanied by enhancing protein carbonylation, a marker of oxidative stress, by 40% (p<0.05). To assess the role of Tim44, it was downregulated by small interfering RNA in cultured neonatal rat ventricular myocytes (NRVMs). Knockdown of Tim44 significantly decreased SOD2 protein levels in mitochondrial fractionation (22%, p<0.05), with no significant changes in its mRNA levels. Furthermore, knockdown of Tim44 significantly increased protein carbonylation (20%, p<0.05) and cleaved caspase 3 (47%, p<0.05) and decreased cell viability (69%, p<0.05), assessed by cell titer assay, in H2O2-treatred NRVMs.

Conclusions

Downregulation of Tim44 exacerbates oxidative stress-induced ROS production and cardiomyocytes death, which is associated with a decrease in mitochondrial SOD2. Endogenous Tim44 might play a protective role in cardiac remodeling by attenuating oxidative stress and cardiomyocyte death via SOD2 import into mitochondria.

P1606Glutamine-fructose-6-phosphate amidotransferase 2 mediates isoproterenol-induced cardiac hypertrophy by increasing Akt O-GlcNAcylation through hexosamine biosynthesis pathway

Background

Cardiac hypertrophy is an independent risk factor for heart failure and cardiac death. Hexosamine biosynthesis pathway (HBP), an accessory pathways of glycolysis, is known to be involved in the attachment of O-linked N-acetylglucosamine motif (O-GlcNAcylation) to proteins, a post-translational modification. However, the role of HBP has not been determined in pathological cardiac hypertrophy.

Purpose

The purpose of this study to examine whether glutamine-fructose-6-phosphate amidotransferase 2 (GFAT2), a critical enzyme of HBP, mediates cardiac hypertrophy by protein O-GlcNAcylation and activating hypertrophic signaling in cardiomyocytes.

Methods and results

C57BL/6J mice were treated with isoproterenol (ISO: 15 mg/kg/day, 1 week) with or without 6-Diazo-5-oxo-L-norleucine (DON, an inhibitor of GFAT: 500 μg/kg/day, 1week). ISO-treated mice (ISO+vehicle) showed cardiac hypertrophy, which were attenuated in ISO and DON-treated mice (ISO+DON) (heart weight to tibial length ratio: 7.70±0.09 vs. 7.11±0.15 mg/mm, n=12, p<0.05, left ventricular wall thickness: 1.05±0.02 vs. 0.86±0.03 mm, n=6, p<0.05). Cardiomyocyte cross-sectional area was also decreased in ISO+DON compared with ISO+vehicle (309±25 vs. 252±13 mm2, n=,3 p<0.05). Whereas expression levels of GFAT2 and protein O-GlcNAcylation in the heart were increased in ISO+vehicle compared with control+vehicle by 3.3 and 1.5 folds, respectively (n=9 and n=9, p<0.05), expression levels of O-GlcNAc transferase (OGT) and the β-N-acetylglucosaminidase (OGA), other enzymes regulating O-GlcNAcylation, were not altered in both groups, indicating that ISO activated HBP by GFAT2. Protein O-GlcNAcylation in ISO+DON was lower than that in ISO+vehicle by 83% (n=9, p<0.05). In addition, phosphorylation of Akt, a critical mediator of cardiac hypertrophy, but not other mediators of cardiac hypertrophy such as ERK, JNK, or p38MAPK, was significantly decreased in ISO+DON by 76% (n=9, p<0.05). In cultured neonatal rat ventricular myocytes, treatment with ISO (1μM, 12h) increased the expression levels of GFAT2 and protein O-GlcNAcylation by 1.3 and 1.5 folds, respectively (n=6 and n=6, p<0.05), but not GFAT1. Furthermore, ISO stimulation increased a direct O-GlcNAcylation of Akt by 1.4 folds (n=3, p<0.05). Downregulation of GFAT2 by RNA silencing decreased cell size by 82% (n=6, p<0.05) and protein O-GlcNAcylation and phosphorylation of Akt by 76% and 54%, respectively (n=9 and n=9, p<0.05) in cardiomyocyte treated with ISO. Conversely, administration of glucosamine, a substrate of HBP, increased protein of O-GlcNAcylation and phosphorylation of Akt by 1.3 and 1.8 folds, respectively (n=6 and n=6, p<0.05).

Conclusions

GFAT2, a limiting enzyme of HBP, mediates pathological cardiac hypertrophy by Akt activation probably due to its O-GlcNAcylation. GFAT2-O-GlcNAcylation-Akt pathway might be a potential novel therapeutic target for cardiac hypertrophy.

P6305Activation of invariant natural killer T cells ameliorates doxorubicin-induced cardiomyopathy

Background

Invariant natural killer T (iNKT) cells orchestrate tissue inflammation via regulating various cytokine productions, especially strongly upregulating interferon (IFN)-γ. Activation of iNKT cells have been previously reported to exert protective effects against post-infarcted cardiac remodeling and cardiac ischemia/reperfusion injury. However, the role of iNKT cells has not been determined in doxorubicin (DOX)-induced cardiomyopathy.

Purpose

The purpose of this study was to examine whether the activation of iNKT cells by α-galactosylceramide (αGC), which specifically activates iNKT cells, could affect DOX-induced cardiomyopathy, and if so, to elucidate its downstream target.

Methods

C57BL/6J mice were received the intraperitoneal injection of either αGC (0.1μg/g, n=11) or vehicle (n=13). After 1 week, these mice were treated with a low dose of DOX (18mg/kg via intravenous 3 injections over 1 week), and were followed during 14 days.

Results

DOX mice (DOX+vehicle) showed left ventricular (LV) dysfunction and dilatation, which were significantly ameliorated in DOX mice receiving αGC (DOX+αGC) (LV fractional shortening: 27.4±4.31 vs. 31.5±4.62%, p<0.05, LV end-diastolic diameter: 3.70±0.16 vs. 3.32±0.23mm, p<0.05), with no significant changes in arterial pressure, body weight, and food consumption, 14 days after DOX injection. DOX+vehicle demonstrated a significant decrease in myocardial gene expression of Vα14Jα18, a specific marker of iNKT cells, and IFN-γ compared with control mice. Vα14Jα18 expression levels were higher in DOX+αGC than DOX+vehicle by 9.2 folds (p<0.05). Consistent with this change, IFN-γ was higher in DOX+αGC than DOX+vehicle by 4.4 folds (p<0.05), whereas interleukin (IL)-1, IL-4, IL-6, IL-10, IL-17, IL-23, and tumor necrosis factor (TNF)-α were not altered in both groups. Phosphorylation of Akt, its active form, in the heart was significantly increased in DOX+αGC compared with DOX+vehicle by 1.8 folds (p<0.05).

Conclusions

Activation of iNKT cells by αGC play a protective role against DOX-induced cardiac dysfunction, which was associated with enhancing expression of IFN-γ and activating Akt. Therapies designed to activate iNKT cells might be beneficial to protect the heart from DOX injury.

Expression of cytosolic malic enzyme (ME1) is associated with disease progression in human oral squamous cell carcinoma

Malic enzyme 1 (ME1) is a multifunctional protein involved in glycolysis, the citric acid cycle, NADPH production, glutamine metabolism, and lipogenesis. It is overexpressed in various cancers. We examined the expression of ME1 in 119 oral squamous cell carcinomas (OSCCs) using immunohistochemistry. Malic enzyme 1 expression was moderate to strong in 57 (48%) OSCCs and correlated with pT, pN, clinical stage, and histological grade. In 37 cases with prognostic evaluation, moderate to strong ME1 expression indicated a worse prognosis than did weak ME1 expression. Malic enzyme 1 knockdown or inactivation by lanthanide inhibited cell proliferation and motility and suppressed the epithelial-mesenchymal transition in HSC3 human OSCC cells. Knockdown of ME1 also shifted energy metabolism from aerobic glycolysis and lactate fermentation to mitochondrial oxidative phosphorylation, and the redox status from reductive to oxidative. In a mouse tumor model, lanthanide suppressed tumor growth and increased survival time. These findings reveal that ME1 is a valid target for molecular therapy in OSCC.

Expression of MAS1 in breast cancer

MAS1 is a receptor for angiotensin 1-7 (A1-7), which is derived from angiotensin II (A-II) by the action of angiotensin converting enzyme (ACE) 2. MAS1 induces anti-A-II phenotypes, such as vessel dilation and depression of blood pressure. Using immunohistochemistry, we examined the role of MAS1 in 132 cases of invasive ductal carcinoma (IDC) of the breast. While benign mammary tissues expressed MAS1 at high levels, MAS1 expression was attenuated in all IDC, especially in scirrhous IDC. The decrease in MAS1 expression was associated with tumor growth, lymph node metastasis, and grade. MAS1 expression was inversely associated with the proliferation index and epidermal growth factor receptor and human epidermal growth factor receptor-2 expression. Of the 132 cases, 12 (9.1%) were triple-negative breast cancer (TNBC) cases. All TNBC cases (the 12 cases and the additional 36 cases using a tissue array) expressed MAS1. Using the TNBC cell lines 4T1 and MDA-MB-468, which expresses MAS1, we found that cell growth, anti-apoptotic survival and invasion were suppressed by MAS1 activation with A1-7 treatment and enhanced by MAS1 knockdown. In contrast, synergic effect was found between tamoxifen and A1-7 in a luminal A breast cancer cell line, MCF-7. Combination treatment with cisplatin, an ACE2 activator, and an A-II type 1 receptor blocker showed synergic effects on tumor growth inhibition of 4T1 tumors in a syngeneic mouse model. These findings suggest that MAS1 might act as an inhibitory regulator of breast cancer and may be a possible molecular target for this malignancy.

HuD promotes progression of oral squamous cell carcinoma

Head and neck cancer, including oral squamous cell carcinoma (OSCC), ranks as the sixth most common malignancy worldwide. Overall 5-year survival rates of OSCC have not significantly improved during the past 3 decades and the 5-year survival rate is less than 50%. Several invasion grading systems have been employed in OSCC, however, their utility is still controversial. HuD belongs to the Hu protein family and acts as an RNA-binding protein involved in mRNA stability and translational regulation. Although HuD has a pivotal role for neuronal differentiation, the functional role of HuD in OSCCs is still unclear. In this study, we examined HuD expression in 82 OSCC cases. Expression of HuD was observed in 36.6% of OSCCs and significantly associated with histological differentiation, nodal metastasis and mode of invasion. HuD expression in high-metastatic HSC3 cells was higher than in low-metastatic HSC4 cells, and inhibition of invasion ability and activation of caspase-3 were shown by HuD siRNA-treated HSC3 cells. Furthermore, we clarified that HuD regulates expression of vascular endothelial growth factor (VEGF)-A, VEGF-D, matrix metallopeptidase (MMP)-2 and MMP-9. These results suggest that HuD is a useful diagnostic and therapeutic target in OSCCs.

Prox1 and FOXC2 act as regulators of lymphangiogenesis and angiogenesis in oral squamous cell carcinoma

Prospero homeobox 1 (Prox1) and forkhead box (FOX) C2 regulate angiogenesis and/or lymphangiogenesis. However, the detailed role and function of Prox1 and FOXC2 in cancer remains controversial. In the present study, we examined the expression of Prox1 and FOXC2 proteins in specimens from 163 cases with oral squamous cell carcinoma (OSCC). Furthermore, the role of Prox1 and FOXC2 in cancer cell growth and invasion was evaluated in cultured OSCC cells. Prox1 expression was significantly associated with local progression of the tumor (P = 0.0023), clinical stage (P<0.0001), lymphovessel density (LVD) (P<0.0001), nodal metastasis (P<0.0001), and worse prognosis (P<0.0001). Immunoreactivity of FOXC2 was strongly correlated with microvessel density (MVD) (P<0.0001) and poor prognosis (P = 0.0076). In vitro analysis demonstrated that Prox1 regulates cell growth, proliferation, invasion, and lymphangiogenesis by activating vascular endothelial growth factor (VEGF)-C expression. Furthermore, FOXC2 enhanced the expression level of Prox1 and promoted angiogenesis by enhancement of VEGF-A expression. Our results suggested that Prox1 and FOXC2 play key roles in OSCC progression and that further studies focusing on these proteins may yield useful insights for diagnosis and therapy of OSCC.

Protumoral roles of melanoma inhibitory activity 2 in oral squamous cell carcinoma

BACKGROUND

The role of melanoma inhibitory activity 2 (MIA2) was examined in human oral squamous cell carcinoma (OSCC).

METHODS

MIA2 role was examined by immunohistochemistry of human OSCCs and knockdown studies using human 3 OSCC cell lines with MIA2 expression.

RESULTS

MIA2 expression was observed in 62 (66.7%) of 93 OSCCs and was associated with tumour expansion and nodal metastasis. Melanoma inhibitory activity 2 expression was inversely correlated with intratumoral infiltration of lymphocytes. Invasion and anti-apoptotic survival were reduced by MIA2 knockdown in HSC3 cells. MOLT-3 lymphocytes infiltrating the HSC3 cell layer was enhanced by MIA2 knockdown or MIA2 depletion with the antibody. In HSC3 cells, MIA2 knockdown decreased the expressions of vascular endothelial growth factor (VEGF), VEGF-C, and VEGF-D. The downregulation of VEGF-C and -D was caused by inhibition of p38 and extracellular signal-regulated kinase (ERK)1/2, respectively. Melanoma inhibitory activity 2 was co-precipitated with integrin α4 andα5 in HSC3 cells. Integrin α4 knockdown decreased p38 phosphorylation and increased apoptosis, whereas integrin α5 knockdown decreased c-Jun N-terminal kinase (JNK) phosphorylation and apoptosis. Inhibition of JNK decreased apoptosis in the HSC3 cells.

CONCLUSION

These findings suggest that the roles of MIA2 might be based on the variety of the integrins and the subtypes of mitogen-activated protein kinase.

Distribution of amyloid burden differs between idiopathic normal pressure hydrocephalus and Alzheimer's disease

This study aimed to elucidate the incidence and distribution of the cortical retention of Pittsburgh compound B (PIB) in patients with idiopathic normal pressure hydrocephalus (iNPH) and clarify the differences from those in patients with Alzheimer's disease (AD). Ten patients with iNPH without any clinical signs indicative of AD were enrolled in this study. Cerebral retention of PIB in positron emission tomography (PET) in iNPH patients was compared with those in seven age-matched AD patients. The CSF levels of β-amyloid 1-42 peptide (Aβ42), which inversely decrease with cerebral amyloid burden, were also measured. Three of the ten patients with iNPH showed increased cortical PIB retention. Although the mean cortical SUV ratios were similar, the distribution of PIB retention differed widely between the patients with iNPH and AD. PIB retention was limited to the high-convexity parasagittal areas in iNPH patients, whereas it spread over the frontal and parietotemporal areas in AD. The coronal images of PIB-PET were more informative than conventional transverse images in evaluating the distribution pattern of cortical PIB retention. Two iNPH patients with higher cortical PIB retention had the lowest levels of CSF Aβ42, indicating that PIB retention in iNPH would not reflect a simple delay in PIB clearance but its binding to existing Aβ amyloid in the brain. Our results indicate that iNPH is one of the diseases exhibiting cortical PIB retention. The characteristic distribution of PIB retention in iNPH could be useful in the differential diagnosis between iNPH and AD.

Tropomyosin receptor kinases B and C are tumor progressive and metastatic marker in colorectal carcinoma

Members of the tropomyosin receptor kinase (Trk) family have a high affinity for neurotrophins and regulate neuronal survival. The role of Trks in cancer is still controversial. The expression and role of TrkB and TrkC were examined in colorectal cancer (CRC). Immunohistochemical analysis of TrkB and TrkC was performed in 133 patients with CRC. Using human CRC cell lines, expression of vascular endothelial growth factor (VEGF) and transforming growth factor β, cell growth, invasion, and apoptosis were examined by knockdown methods. Immunohistochemistry showed positive results of TrkB and TrkC (23.3% and 12.8%, respectively). TrkB expression was associated with local progression (P = .0284), clinical stage (P = .0026), nodal metastasis (P = .0068), and peritoneal metastasis (P = .0026). TrkC expression was only related to liver metastasis (P = .0001). Coexpression of TrkB or TrkC and their ligands was found in 80.6% and 82.4% of cases, respectively. In vitro analysis using human CRC cells showed that TrkB positively regulated gene expression of VEGF-A (P < .05) and VEGF-C (P < .05), whereas TrkC suppressed transforming growth factor β expression (P < .05). TrkB and TrkC induced cell growth (P < .05) and invasion (P < .05), respectively. Both TrkB and TrkC showed antiapoptotic effect (P < .05). These results suggest that TrkB and TrkC have a tumor progressive function and may be a useful diagnostic and therapeutic target in CRC.

Successful treatment of monomorphic primary central nervous system post-transplantation lymphoproliferative disorder 5 years after kidney transplantation

A 31-year-old man underwent living-related kidney transplantation in 2004 as a consequence of primary focal segmental glomerulosclerosis (FSGS). Four years after the transplantation, we confirmed nephrotic syndrome caused by recurrent FSGS. We performed plasmapheresis and low-density lipoprotein adsorption. We also combined steroid therapy with a reduction in the dose of tacrolimus and an increased dose of mycophenolate mofetil. The nephrotic syndrome improved dramatically with this combined therapeutic approach. However, 10 months after these treatments, he revisited our hospital because of altered consciousness. We detected multiple tumor masses in his brain that were ring enhanced on contrast magnetic resonance imaging. Consequently, we suspected primary central nervous system post-transplantation lymphoproliferative disorder (CNS-PTLD). We performed a craniotomy to biopsy the brain tumors. The biopsy specimen showed Epstein-Barr virus-associated diffuse large B-cell lymphoma. There is no definitive treatment for CNS-PTLD. Therefore, we treated the primary CNS-PTLD successfully with whole-brain radiation and discontinuation of immunosuppression therapy.

MicroRNA-34a upregulation during seizure-induced neuronal death

MicroRNAs (miRNAs) are short, noncoding RNAs that function as posttranscriptional regulators of gene expression by controlling translation of mRNAs. A subset of miRNAs may be critical for the control of cell death, including the p53-regulated miRNA, miR-34a. Because seizures activate p53, and p53-deficient mice are reportedly resistant to damage caused by prolonged seizures, we investigated the role of miR-34a in seizure-induced neuronal death in vivo. Status epilepticus was induced by intra-amygdala microinjection of kainic acid in mice. This led to an early (2 h) multifold upregulation of miR-34a in the CA3 and CA1 hippocampal subfields and lower protein levels of mitogen-activated kinase kinase kinase 9, a validated miR-34a target. Immunoprecipitation of the RNA-induced silencing complex component, Argonaute-2, eluted significantly higher levels of miR-34a after seizures. Injection of mice with pifithrin-α, a putative p53 inhibitor, prevented miR-34a upregulation after seizures. Intracerebroventricular injection of antagomirs targeting miR-34a reduced hippocampal miR-34a levels and had a small modulatory effect on apoptosis-associated signaling, but did not prevent hippocampal neuronal death in models of either severe or moderate severity status epilepticus. Thus, prolonged seizures cause subfield-specific, temporally restricted upregulation of miR-34a, which may be p53 dependent, but miR-34a is probably not important for seizure-induced neuronal death in this model.

MR imaging of ventral thalamic nuclei

BACKGROUND AND PURPOSE

The Vim and VPL are important target regions of the thalamus for DBS. Our aim was to clarify the anatomic locations of the ventral thalamic nuclei, including the Vim and VPL, on MR imaging.

MATERIALS AND METHODS

Ten healthy adult volunteers underwent MR imaging by using a 1.5T whole-body scanner. The subjects included 5 men and 5 women, ranging in age from 23 to 38 years, with a mean age of 28 years. The subjects were imaged with STIR sequences (TR/TE/TI = 3200 ms/15 ms/120 ms) and DTI with a single-shot echo-planar imaging technique (TR/TE = 6000 ms/88 ms, b-value = 2000 s/mm(2)). Tractography of the CTC and spinothalamic pathway was used to identify the thalamic nuclei. Tractography of the PT was used as a reference, and the results were superimposed on the STIR image, FA map, and color-coded vector map.

RESULTS

The Vim, VPL, and PT were all in close contact at the level through the ventral thalamus. The Vim was bounded laterally by the PT and medially by the IML. The VPL was bounded anteriorly by the Vim, laterally by the internal capsule, and medially by the IML. The posterior boundary of the VPL was defined by a band of low FA that divided the VPL from the pulvinar.

CONCLUSIONS

The ventral thalamic nuclei can be identified on MR imaging by using reference structures such as the PT and the IML.

The signal-induced phospholipid degradation cascade and protein kinase C activation

Acting in synergy with diacylglycerol, unsaturated free fatty acids such as arachidonic, oleic, linoleic, linolenic and docosahexaenoic acids dramatically activate some members of the protein kinase C family at the basal level of Ca2+ concentration. It is plausible that phospholipase C and phospholipase A2, and possibly phospholipase D as well, are involved in the activation of protein kinase C. Presumably, this enzyme activation is integrated into the signal-induced membrane phospholipid degradation cascade, prolonging the activation of protein kinase C. The sustained activity of this enzyme appears to be of importance for long-term cellular responses such as development of neuronal plasticity and gene activation.

Multitensor tractography enables better depiction of motor pathways: initial clinical experience using diffusion-weighted MR imaging with standard b-value

BACKGROUND AND PURPOSE

The purpose of this work was to test the feasibility of using high angular resolution diffusion imaging (HARDI)-based multitensor tractography to depict motor pathways in patients with brain tumors.

MATERIALS AND METHODS

Ten patients (6 males and 4 females) with a mean age of 52 years (range, 9-77 years) were scanned using a 1.5T clinical MR unit. Single-shot echo-planar imaging was used for diffusion-weighted imaging (repetition time, 6000 ms; excitation time, 88 ms) with a diffusion-sensitizing gradient in 32 orientations and a b-value of 1000 s/mm(2). Data postprocessing was performed using both the conventional single- and multitensor methods. The depiction rate of the 5 major components of the motor pathways, that is, the lower extremity, trunk, hand, face, and tongue, was assessed.

RESULTS

Motor fibers on both lesional and contralesional sides were successfully depicted by both the single-tensor and multitensor techniques. However, with the single-tensor model, the depiction of motor pathways was typically limited to the fibers of trunk areas. With the multitensor technique, at least 4 of 5 major fiber bundles arising from the primary motor cortex could be identified.

CONCLUSION

HARDI-based multitensor tractography using a standard b-value (1000 s/mm(2)) can depict the fiber tracts from the face and tongue regions of the primary motor cortex.

Microarray profile of seizure damage-refractory hippocampal CA3 in a mouse model of epileptic preconditioning

A neuroprotected state can be acquired by preconditioning brain with a stimulus that is subthreshold for damage (tolerance). Acquisition of tolerance involves coordinate, bi-directional changes to gene expression levels and the re-programmed phenotype is determined by the preconditioning stimulus. While best studied in ischemic brain there is evidence brief seizures can confer tolerance against prolonged seizures (status epilepticus). Presently, we developed a model of epileptic preconditioning in mice and used microarrays to gain insight into the transcriptional phenotype within the target hippocampus at the time tolerance had been acquired. Epileptic tolerance was induced by an episode of non-damaging seizures in adult C57Bl/6 mice using a systemic injection of kainic acid. Neuron and DNA damage-positive cell counts 24 h after status epilepticus induced by intraamygdala microinjection of kainic acid revealed preconditioning given 24 h prior reduced CA3 neuronal death by approximately 45% compared with non-tolerant seizure mice. Microarray analysis of over 39,000 transcripts (Affymetrix 430 2.0 chip) from microdissected CA3 subfields was undertaken at the point at which tolerance was acquired. Results revealed a unique profile of small numbers of equivalently up- and down-regulated genes with biological functions that included transport and localization, ubiquitin metabolism, apoptosis and cell cycle control. Select microarray findings were validated post hoc by real-time polymerase chain reaction and Western blotting. The present study defines a paradigm for inducing epileptic preconditioning in mice and first insight into the global transcriptome of the seizure-damage refractory brain.

Anti-p97/VCP antibodies: an autoantibody marker for a subset of primary biliary cirrhosis patients with milder disease?

We previously reported that 12.5% of primary biliary cirrhosis (PBC) sera reacted with a 95 kDa cytosol protein (p95c) that was subsequently identified as a p97/valosin-containing protein (VCP). The clinical features and course of the six anti-p97/VCP-positive PBC patients with Scheuer's stage 1 and 2 liver biopsies were monitored for an average of 15 years. This group was compared with 50 PBC patients that did not have detectable anti-VCP. Autoantibodies to a full-length recombinant p97/VCP were assayed by immunoprecipitation. All six PBC patients with anti-VCP had antibodies to the mitochondrial pyruvate dehydrogenase complex-E2 antigen as measured by an addressable laser bead immunoassay. The first was a male with no evidence of liver failure that died of cerebral infarction at the age of 85. The second was a 73-year-old female with Hashimoto's thyroiditis who has remained clinically stable without ursodeoxycolic acid (UDCA) treatment. Although the third had no HCV antibodies, he developed hepatocellular carcinoma at the age of 76 and died of renal failure at 78. The fourth was a 50-year-old female who remained clinically stable during follow-up and the fifth with Hashimoto's thyroiditis and stable liver function following UCDA treatment. The sixth was a male patient presenting a mild clinical course. The clinical course of these patients was in contrast to the 50 comparison group PBC patients who did not have anti-p97/VCP. As the six PBC patients with anti-p97/VCP antibodies had slowly progressive liver disease and no mortality related to autoimmune liver disease, our observations suggest that this autoantibody might be an indicator of a favourable prognosis.

Diffusion-weighted MR imaging in carotid angioplasty and stenting with protection by the reversed carotid arterial flow

BACKGROUND AND PURPOSE

Distal embolism during carotid angioplasty with stent (CAS) can be protected by a flow-reversal device. Diffusion-weighted MR imaging was used to evaluate this protective procedure and perform a comparison with the control.

METHODS

Cases of CAS with protection procedures were included in this study. Sixty-five men (68 procedures) and 5 women (5 procedures), with an average age of 68.8 years, having severe carotid stenosis were treated in our department between 2002 and 2004. Eleven cases were treated with the Parodi Anti-Emboli System, with which the internal carotid blood flow is reversed by simultaneous occlusion of the proximal common carotid artery and external carotid artery. Diffusion-weighted MR imaging was performed within 1-3 days after CAS. As controls, data from diffusion-weighted MR imaging in 26 patients who had diagnostic angiography were included.

RESULTS

Diffusion-weighted MR imaging in diagnostic angiography showed 11.5% appearance of ischemic spots after procedures. In the Parodi Anti-Emboli System, this value was 18.2%. In the CAS group, ischemic lesions appeared only in the hemisphere ipsilateral to carotid stenosis. There were no ischemic lesions in the opposite carotid or vertebrobasilar territory. The appearance rate of new ischemic spots was not significantly different between the control group and the group of CAS with Parodi Anti-Emboli System (chi2 test, P = .6227, Fisher exact method).

CONCLUSIONS

Protection results obtained with the Parodi system were excellent and comparable with conventional angiography.

Elevated expression of C10orf3 (chromosome 10 open reading frame 3) is involved in the growth of human colon tumor

After analysing gene-expression profiles of colon cancers on a cDNA microarray containing cDNAs corresponding to 23 040 human genes, we focused on a gene annotated as C10orf3 (chromosome 10 open reading frame 3), whose expression was elevated in colorectal cancers (CRC) as well as in tumors arising in the stomach, lung, pancreas, and breast. The gene encodes a putative 464-amino-acid protein containing a domain known as AAA (ATPases associated with a variety of cellular activities). Western blot analysis using an antibody to the gene product confirmed that the protein was overexpressed in nine of the 15 clinical cancer tissues examined, compared to corresponding noncancerous epithelial cells. A subsequent proteomics analysis revealed that C10orf3 product associated with the product of tumor susceptibility gene 101 (TSG101), and that C10orf3 downregulated TSG101 in a post-transcriptional manner. Expression of short interfering RNA in cells derived from CRC caused significant decreases in C10orf3 expression and inhibited growth of the transfected cells, which was associated with increased apoptotic cells. These data suggest that elevated C10orf3 expression might play an essential role in the growth of cancer cells, and that suppression of C10orf3-mediated signal transduction may be a novel therapeutic strategy to a wide range of human tumors.

Autoantibodies from primary biliary cirrhosis patients with anti-p95c antibodies bind to recombinant p97/VCP and inhibit in vitro nuclear envelope assembly

We have reported previously that p95c, a novel 95-kDa cytosolic protein, was the target of autoantibodies in sera of patients with autoimmune hepatic diseases. We studied 30 sera that were shown previously to immunoprecipitate a 95 kDa protein from [(35)S]-methionine-labelled HeLa lysates and had a specific precipitin band in immunodiffusion. Thirteen sera were available to test the ability of p95c antibodies to inhibit nuclear envelope assembly in an in vitro assay in which confocal fluorescence microscopy was also used to identify the stages at which nuclear assembly was inhibited. The percentage inhibition of nuclear envelope assembly of the 13 sera ranged from 7% to 99% and nuclear envelope assembly and the swelling of nucleus was inhibited at several stages. The percentage inhibition of nuclear assembly was correlated with the titre of anti-p95c as determined by immunodiffusion. To confirm the identity of this autoantigen, we used a full-length cDNA of the p97/valosin-containing protein (VCP) to produce a radiolabelled recombinant protein that was then used in an immunoprecipitation (IP) assay. Our study demonstrated that 12 of the 13 (93%) human sera with antibodies to p95c immunoprecipitated recombinant p97/VCP. Because p95c and p97 have similar molecular masses and cell localization, and because the majority of sera bind recombinant p97/VCP and anti-p95c antibodies inhibit nuclear assembly, this is compelling evidence that p95c and p97/VCP are identical.

Repositioning of the vertebral artery with titanium bone fixation plate for trigeminal neuralgia

BACKGROUND

Trigeminal neuralgia is usually treated by the padding method using Teflon felt. However this can not be done in certain cases in whom a large tortuous vertebrobasilar artery compresses the fifth nerve. The transposition method using the sling may be an alternative method. But this method is not an easy procedure and requires a relatively large craniotomy. Two cases were treated by a new and simpler effective technique.

CLINICAL PRESENTATION

Two cases of the trigeminal neruralgia were treated. The first case was a 71 year-old male and the second case was a 63 year-old male. The history of the medical treatments were similar and both cases had had trigeminal nerve blocks and were prescribed carbamazepin. However, the pain control was insufficient in both cases. In both cases, three dimensional computerized tomography showed the large tortuous right vertebral artery ran just behind the clivus and compressed the right trigeminal nerve. In the second case past history showed a recent hypertensive cerebellar hemorrhage.

TECHNIQUE AND RESULTS

A right suboccipital craniotomy were performed in both cases. In both cases, the right vertebral artery compressed the trigeminal nerve in a rostral direction. The sling technique with nylon sutures was tried in both cases but failed during surgery. Then, the bone fixation stainless plate was cut to 10 cm in length and pre-shaped with pliers. After being shaped, the distal end of the plate was inserted between the vertebral artery and fifth nerve and the proximal end of the plate was fixed to the skull by screw. The fifth nerve was completely isolated from the artery as they were in direct contact. After surgery, the pain disappeared completely during the follow-up of one and a half year in the first case and 9 months in the second case.

CONCLUSION

The plate can be bent and curved with plier to suit each individual case. This technique is easily applied even when the slings or other isolation technique is not available and appeared to achieve the mechanically stronger reposition and fixation of a very large and tortuous artery away from the trigeminal nerve.

Iron lactate-induced osteopenia in male Sprague-Dawley rats

Osteopenia was induced in rats fed a diet containing 50,000 ppm (5%) iron lactate for 2 or 4 weeks. Blood chemistry, urinalysis, and bone histomorphometry of the proximal tibial metaphysis were performed. Urinary pyridinoline and deoxypyridinoline and the osteoclast number per bone surface were selected for the measurement of dynamic resorption. The osteoclast surface, eroded surface, and osteoblast surface increased at both ends of the exposure periods, and bone resorption and formation both increased. The bone volume, trabecular thickness, and trabecular number decreased, and the secondary spongiosa of proximal metaphysis showed a marked bone loss. However, no mineralization defect was observed. At the end of the 2-week exposure period, biomarkers of osteoclasts and osteoblasts had increased the most, and the osteoblast surface, osteoclast surface, and osteoclast number per bone surface increased with prolonged exposure. The pathological changes of the bone lesion in iron lactate-overloaded rats were similar to those in rats of the osteoporotic model, because they consisted of changes reflecting the increase of bone resorption and formation without an osteomalacic change. However, the decline of serum parathyroid hormone (PTH) levels was different from that of the osteoporosis model rat. We concluded iron-induced bone lesions probably differ from those of low turnover bone diseases.

[A pediatric case of intractable complex partial seizures associated with mesial temporal lobe astrocytoma: usefulness of interictal epileptiform discharges in the present case]

The patient was a 10-year-old male with normal developmental milestones. He had medically intractable complex partial seizures since the age of 7 years. At the age of 10 years, he had focal motor seizures of the right face, and a head CT scan showed a calcified lesion in the left mesial temporal region. The tumor exhibited low intensity on T 1-weighted and high intensity on T 2-weighted MR images, and was not enhanced by gadolinium-diethylenetriamine pentaacetic acid. Interictal SPECT showed hypoperfusion in the left temporal region. One-day video/EEG monitoring revealed very frequent epileptiform discharges which occurred only during sleep period exclusively in the left anterior-to-middle temporal region. The patient underwent lesionectomy with the guidance of electrocorticography. The histological study of the resected tissue showed astrocytoma. After surgery he has had no seizures for 10 months. It was concluded that very frequent interictal epileptiform discharges strictly localized to the temporal lobe at which MRI-identified tumor was present could be predictive of epileptogenic zone in the present patient in whom clinical symptoms and the results of other studies were also concordant.

Basic studies on the equivalent cross-relaxation rate imaging (equivalent CRI)--phantom studies

We have studied saturation transfer in hydrophilic, cross-linked copolymer gels from irradiated polymer protons to observed water protons, using f2 (ppm) profiles of [1 - (I(infinity)/I(0))], [(I(0)/I(infinity)) - 1] or 1/T(IS)(H2O), where I(0) and I(infinity) are the longitudinal magnetization of the observed water protons before and after long-time-f2-irradiation on polymer protons, respectively, and 1/T(IS)(H2O) is the cross-relaxation rate. (A) [1 - (I(infinity)/I(0))] (magnetization transfer ratio, MTR) was used in magnetic resonance imaging (MRI) as the MTR imaging. 1/T(IS)(H2O) (cross-relaxation rate) was used in the imaging of the magnetization transfer rate constant. This method was quite time-consuming compared with MTR imaging. However, f2 (ppm) profiles of [(I(0)/I(infinity)) - 1] correlated well with corresponding profiles of 1/T(IS)(H2O), because [(I(0)/I(infinity)) - 1] is equal to 1/[T(IS)(H2O)/T1(H2O)]. These results lead us to the conclusion that [(I(0)/I(infinity)) - 1] might be applicable to cross-relaxation rate (CR)-like imaging, i.e. equivalent CRI. (B) W (%) (dry weight) profiles of [(I(0)/I(infinity)) - 1] and 1/T(IS)(H2O), obtained by near-resonance f2-irradiation, seem to indicate participation of molecular rigidity and an amount of bound water. However, those values, monitored with off-resonance f2-irradiation, seem to be independent of monomer composition and to indicate mainly participation of rigidity, i.e. W (%) of copolymer gels.

Mechanism of protection by S-(1,2-dicarboxyethyl)glutathione triester against acetaminophen-induced hepatotoxicity in rat hepatocytes

Treatment with the triester of S-(1,2-dicarboxyethyl)glutathione (DCE-GS) prevented the hepatotoxicity induced by acetaminophen via elevation of the glutathione (GSH) level in rat hepatocytes. This elevation of the GSH level in rat hepatocytes by DCE-GS triester was dose- and time-dependent (2.1-fold in 24 h with 0.5 mm). DCE-GS triester increased the GSH level much more effectively than GSH, DCE-GS, and DCE-GS monoester and diester. Furthermore, the activity of y-glutamylcysteine synthetase (gamma-GCS), the rate-limiting enzyme in GSH biosynthesis, was also increased by DCE-GS triester treatment (1.4-fold in 24 h with 1.0 mm). In contrast, with a rat liver homogenate, DCE-GS increased the y-GCS activity, whereas DCE-GS triester had no effect on this activity. These results suggested that DCE-GS triester, which is transported into hepatocytes much more effectively than DCE-GS and other DCE-GS esters due to its greater lipophilicity, was hydrolyzed to DCE-GS, and then the DCE-GS produced increased the GSH level via activation of gamma-GCS in rat hepatocytes.

Effects of photoperiod and melatonin on the development of growth hormone cells and the pituitary-adrenal axis in the Djungarian hamster, Phodopus sungorus

The development of GH cells and the pituitary-adrenal axis was morphologically examined in male Djungarian hamsters (Phodopus sungorus) exposed to short days and those kept under long days and receiving daily afternoon injections of melatonin, from the time of weaning (20 days) until 100 days of age. The postnatal increase in area of ACTH cells under long days was inhibited in short-day-exposed or melatonin-treated animals. It was suggested that a short photoperiod may suppress, via melatonin, the development of ACTH cells. GH cells were not affected by age, photoperiod or exogenous melatonin. Under long days, the zona fasciculata decreased in volume with age, while the zona reticularis increased. Such changes in the volumes of these adrenocortical zones were depressed under short days. In addition, the volumes of the zona fasciculata and zona reticularis in long-day-housed animals became respectively larger and smaller subsequent to orchidectomy and melatonin administration. These results suggest that fasciculata cells in deeper levels become progressively differentiated into reticularis cells, that short photoperiod inhibits development of both zonae, and that such an inhibition is caused mainly by the decreased secretion of androgens.

Evaluation of the prognostic factors after thymoma resection

We discuss the prognostic factors of thymoma clinicopathologically. Regarding the survival rate by the clinical stage classification of Masaoka, significant correlation was made between stage I and stage III (P < 0.05) and stage I and stage IVa (P < 0.03). The tumor resectability was classified into complete and incomplete resection, and a significant difference was shown by the survival rate of the complete resection at P < 0.0001. Regarding the survival rate by the invasive organ of the tumor, significant correlation was made between no invasion and the great vessel invasion (P < 0.0004) and between invasion except for the great vessel and great vessel invasion (P < 0.004). As for the histological type, the tendency in which the epithelial cell type predominancy increased with the progress of the clinical stage was shown. A significant correlation was not shown in the evaluation by adjuvant therapy. However, recently we have done chemotherapy and/or radiotherapy periodically for invasive thymoma.

Central GABAergic innervation of the mammalian pineal gland: a light and electron microscopic immunocytochemical investigation in rodent and nonrodent species

Light and electron microscopic immunocytochemical observations were made to demonstrate central pinealopetal fibers immunoreactive for gamma-aminobutyric acid (GABA) and synapses between their terminals and pinealocytes in the pineal gland of four rodent (Wistar-King rat; mouse; Syrian hamster, Mesocricetus auratus; Hartley strain guinea pig) and one nonrodent (tree shrew, Tupaia glis) species. GABA-immunoreactive myelinated and unmyelinated fibers and endings were found in the parenchyma of the pineal gland of all the animals examined. In the rodent species, GABAergic fibers were mainly found in the intermediate and proximal portions of the pineal gland and were nearly or entirely absent in the distal portion of the gland. Abundant GABAergic fibers were evenly distributed throughout the gland of the tree shrew. In all the animals, the habenular and posterior commissures contained abundant GABA-positive fibers, and some of them were followed to the pineal gland. GABA-positive endings made synaptic contact with pinealocytes, occasionally in mice and guinea pigs, and frequently in tree shrews; no synapses were observed in Syrian hamsters and rats. In the pineal gland of all the animals, GABA-immunoreactive cell bodies were not detected, and sympathetic fibers were not immunoreactive for GABA. These data indicate that GABAergic fibers are main pinealopetal projections from the brain. In view of the difference in the distribution of these fibers, central GABAergic innervation may play a more significant role in nonrodents than in rodents. The frequent occurrence of GABAergic synapses on pinealocytes in the tree shrew suggests that GABA released at these synapses directly controls activity of pinealocytes of this animal.

Localization of cellubrevin-related peptide, endobrevin, in the early endosome in pancreatic beta cells and its physiological function in exo-endocytosis of secretory granules

Cellubrevins are integral membrane proteins expressed in a wide variety of tissues and usually localized in recycling vesicles. Here, we investigated the cellular localization of a cellubrevin-related peptide, endobrevin, in pancreatic (beta) cells and its implication in the exo-endocytosis of insulin and (gamma)-amino butyric acid (GABA). Immunocytochemistry showed that endobrevin is associated with tubulo-vesicular structures, which are colocalized with early endosomes labeled by early endosome antigen (EEA)-1 in insulinoma MIN6 cells. To determine the cellular localization of endobrevin, we appended the green fluorescent protein (GFP) to endobrevin and the fusion protein was introduced into MIN6 cells. The subcellular localization of GFP-endobrevin was visualized by confocal laser microscopy. Colocalization study based on the expressed GFP-endobrevin and endocytosed Texas-Red(Tx-R) labeled transferrin receptor and immunocytochemistry with anti-EEA1 antibody revealed that endobrevin was preferentially localized in the early endosome. Then, we examined the functional role of endobrevin in the exocytosis of insulin and GABA from pancreatic (beta) cells. Endobrevin overexpression increased the amount of GABA released from MIN6 cells; in contrast, it decreased the glucose-stimulated insulin release from rat islets, MIN6 and INS1-D cells to approximately 50% of the control levels. Both in vitro and in vivo binding studies showed that endobrevin binds to syntaxin 1. Finally, using the fluorescent probe FM4-64, it was revealed that endobrevin overexpression accelerates vesicle recycling. We conclude that (1) endobrevin is localized in the early endosome in pancreatic (beta) cells and (2) endobrevin plays a physiological role in the exo-endocytosis of insulin and GABA from pancreatic (beta) cells, probably via an interaction between endocytic vesicles and the endosome.

The increase of memory T cell subsets in children with idiopathic nephrotic syndrome

Two-color and three-color flow cytometry was carried out to determine whether the memory T cells (CD45RO+ T cells) play a major role in lymphocyte dysfunction of 26 children with idiopathic nephrotic syndrome (INS). The INS patients were divided into three groups: (1) 10 patients who were not receiving glucocorticoid hormone (GCH) and were suffering from acute nephrotic state were referred to as N1; (2) 8 patients who were in remission maintained by GCH therapy alone were referred to as N2; (3) 8 patients who were free of GCH therapy for at least 4 months were referred to as N3. Group N1 demonstrated a significant increase in the percentage of CD45RO+CD4+ T cells and CD45RO+CD8+ T cells (p < 0.05) compared with 11 controls, and these subsets were noted to have a tendency to decrease to control levels in groups N2 and N3. Furthermore, interleukin-2 receptor-alpha expressed subsets in CD45RO+CD4+ T cells (CD45RO+CD4+CD25+ T cells) were also increased only in group N1 (p < 0.02). A similar tendency of absolute counts was observed in these subsets. These results suggest that activated memory T cells reflect lymphocyte dysfunction at initial onset or relapse in INS children.

Separation and assay methods for melatonin and its precursors

Melatonin is an indoleamine hormone that is synthesized from tryptophan via 5-hydroxytryptophan, serotonin and N-acetylserotonin in the vertebrate pineal gland. Many chromatographic and non-chromatographic techniques have been developed and improved for the determination and measurement of melatonin and its related indoleamines. At present, gas chromatography with mass spectrometry and reversed-phase high-performance liquid chromatography with fluorescence or electrochemical detection are widely used for indoleamine determinations in the pineal gland. This review will deal with methods for the separation and determination of the melatonin and its related indoleamines.

Saturation transfer ratio imaging in invasive ductal carcinomas of the breast

A prospective study was performed to investigate the correlations between saturation transfer ratio (STR) and histologic parameters of invasive ductal carcinomas in human breast. The histologic parameters investigated were the extent of fibrosis in the intercellular matrix, dysplastic changes of nuclei, and mitotic index. Twenty-seven patients with breast carcinoma were examined using an off-resonance saturation pulse in conjunction with conventional field-echo T(1)-weighted imaging at frequency offsets of 448 Hz and 1200 Hz from water resonance. The values of STR at frequency offset of 1200 Hz (STR(1200)) increased from non-scirrhous carcinoma to scirrhous carcinoma. Although STR(1200) showed correlation with the extent of fibrosis in the intercellular matrix (p<0.01, n = 27), they did not correlate with the dysplastic changes of nuclei or mitotic index. On the other hand, the values of STR at frequency offset of 448 Hz (STR(448)) demonstrated close correlation to dysplastic changes of nuclei and mitotic index (p<0.01, n = 27). STR(1200) correlates with the structural characteristics and STR(448) correlates with the nature of malignant cells with regard to nuclear dysplasia and mitotic potential.