CMR feature tracking cloud assess right ventricular functional reserve with pulmonary arterial hypertension

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI, Grant-in-Aid for Early-Career Scientists.

Background

  Pulmonary arterial hypertension (PAH) remains a fatal disorder characterized by elevated pulmonary arterial pressure. Survival of the patients with PAH is determined from right ventricular (RV) function. CMR has become an attractive modality for following up and providing prognosis in such patients, and CMR feature tracking has been used as a newer useful parameter to assess RV function. However, it has not yet been determined whether CMR feature tracking can assess RV functional reserve in patients with PAH.

Purpose

We investigated whether CMR feature tracking can estimate RV functional reserve using a rat model with PAH.

Methods

 Rats were received injections with monocrotaline (MCT-rats, n = 19) or solvent (Ctr-rats, n = 5). Four weeks after the injections, we performed CMR on 7-T MRI scanner and imaged retrospective ECG-gated cine MR (16 phases/beat). RV ejection fraction (RVEF) and RV strain were analyzed before and after addition of 0.5∼3 nmol endothelin-1 (ET-1). After the measurements, we dissected trabeculae (length = 1.45 ± 0.07 mm, width = 334 ± 27 µm, thickness = 114 ± 6 µm) from the RVs of rat hearts. Trabeculae were electrically stimulated with 2-s intervals at extracellular Ca2+ of 0.7 and 2.0 mmol/L (24°C). Force and maximum dF/dt (dF/dtmax) were then measured using a silicon strain gauge in the absence and presence of 0.1 µM ET-1.

Results

 MCT-rats showed higher systolic RV pressure (RVP), lower RVEF, and lower RV global longitudinal strain (RVGLS) in CMR imaging and showed lower developed force and lower dF/dtmax in their trabeculae. Correlation between RVGLS and dF/dtmax was higher (r = 0.53, p < 0.05) than that between RVEF and dF/dtmax (r = 0.24). In 5 MCT-rats with preserved RVEF (>50%), RVGLS had already been reduced, suggesting that RVGLS is reduced earlier than RVEF. ET-1 increased developed force and dF/dtmax in trabeculae from MCT-rats (12.2 ± 5.7 to 17.4 ± 3.1 mN/mm2 and 0.08 ± 0.03 to 0.14 ± 0.06 mN/mm2/sec, respectively, n = 6), and ET-1 also increased RVP in MCT-rats and Ctr-rats (49.0 ± 19.3 to 59.7 ± 16.8 mmHg in MCT-rats, n = 6, 17.3 ± 7.5 to 20.4 ± 7.8 mmHg in Ctr-rats, n = 2). According to RV global circumferential strain (RVGCS) and RVEF, we could divide MCT-rats into three groups as follows: MCT-rats with reduced-RVGCS (> -20%)/preserved-RVEF (> 50%), MCT-rats with increased-RVGCS (< -30%)/preserved-RVEF and MCT-rats with reduced-RVGCS/reduced-RVEF. ET-1 reduced RVGCS in MCT-rats with reduced-RVGCS/preserved-RVEF, while ET-1 did not change RVGCS in MCT-rats with increased-RVGCS/preserved-RVEF. MCT-rats with reduced-RVGCS/reduced-RVEF died after injection of ET-1.  In Ctr-rats, ET-1 did not change RVGCS and RVEF.  These results suggest that RVGCS can be useful to assess RV functional reserve.

Conclusion

 CMR feature tracking can estimate RV functional reserve earlier and more accurately than RVEF in rats with PAH.  RV strain may become an important parameter to assess RV functional reserve in patients with PAH.

Mitochondrial connexin43 affects arrhythmogenesis with modulation of mitochondrial KATP channels

Introduction

Connexin43 (Cx43) forms gap junction channels in ventricular muscle and also exits in the inner mitochondrial membrane (mCx43). We have previously reported that carbenoxolone, a blocker of Cx43, increased the occurrence of arrhythmias with modulation of mitochondrial KATP channels (mKATP).

Purpose

To examine how mCx43 and mKATP affect arrhythmogenesis, using cardiac-specific Cx43-deficient (Cx43−/−) mice.

Methods

To generate cardiac-specific Cx43−/− mice, Cx43flox/flox mice were crossed with α-myosin heavy chain (Myh6)-cre+/− mice. The resulting offspring, Cx43flox/flox/ Myh6-cre+/− mice (Cx43−/− mice) and their littermates (Cx43+/+ mice), were used. Trabeculae were dissected from right ventricles of mouse hearts (length ∼0.9 mm, width ∼200 μm, thickness ∼80 μm). Force was measured with a strain gauge, and intracellular Ca2+ (Cai) with fura-2 and a CCD camera (22°C). To assess arrhythmogenesis, the minimal extracellular Ca2+ concentration (Caomin), at which arrhythmias were induced by electrical stimulation (0.3-s stimulus intervals, 100 nM isoproterenol), was determined in mouse trabeculae. Using isolated single ventricular myocytes, mitochondrial membrane potential (ΔΨm) was estimated with tetramethylrhodamine methylester (TMRM) fluorescence, ROS production was estimated with 2',7'-dichlorofluorescein (DCF) fluorescence, and Ca2+ spark frequency was measured with fluo-4 and confocal microscopy. To investigate the roles of mKATP, 0.1 mM diazoxide, a mKATP channel opener, and 0.2 mM 5-hydroxydecanoic acid (5-HD), a mKATP channel inhibitor, were used.

Results

Most of Cx43−/− mice suddenly died within 8 weeks (p<0.01). Cx43 was present in the inner mitochondrial membrane in Cx43+/+ mice, while it was not present in Cx43−/− mice. The resting and developed force and Cai transients by electrical stimulation (2-s stimulus intervals) showed no difference between Cx43−/− and Cx43+/+ mouse trabeculae (n=7). The Caomin in Cx43−/− mice was lower than that in Cx43+/+ mice (p<0.01), and diazoxide increased the Caomin in Cx43−/− mice (p<0.01), suggesting that arrhythmogenesis is increased in Cx43−/− mice and is decreased by diazoxide. Ca2+ spark frequency and DCF oxidation rate in Cx43−/− mice were higher than those in Cx43+/+ mice (p<0.01). They were decreased by diazoxide and were increased by 5-HD (p<0.01). TMRM fluorescence was decreased after electrical stimulation (1-s stimulus intervals) in Cx43−/− mice and was further decreased by 5-HD (p<0.01), suggesting depolarization of ΔΨm in Cx43−/− mice. Such decrease in TMRM fluorescence in Cx43−/− mice was suppressed by diazoxide and did not occur in Cx43+/+ mice.

Conclusions

These results suggest that with modulation of mKATP, mCx43 plays important roles in ΔΨm determination, ROS production, and Ca2+ leak from the sarcoplasmic reticulum, thereby affecting arrhythmogenesis. Therefore, it is likely that mCx43 and mKATP could become a therapeutic target for controlling arrythmias.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Scientific Research (C) from Japan Society for the Promotion of Science

Right ventricular longitudinal strain with CMR can more accurately estimate right ventricular functional reserve in rats with pulmonary arterial hypertension

Background

Right ventricular (RV) function is an important prognostic factor in patients with pulmonary arterial hypertension (PAH). Recently, CMR has become an attractive modality for follow up and providing prognosis in the patients, and strain has been used as a newer parameter to assess contractile properties of ventricle. It has not yet been established, however, whether RV strain with CMR can estimate RV functional reserve in the patients with PAH.

Purpose

We focused on CMR imaging of RV, investigating whether RV longitudinal strain can estimate RV functional reserve using a rat model with PAH.

Method

Rats were given a subcutaneous injection of 60 mg/kg monocrotaline (MCT-rats) or solvent (Ctr-rats). Four weeks after the injection, 25% of MCT-rats died due to RV failure. In the survivors of MCT- (n=19) and Ctr-rats (n=5), retrospective ECG-gated cine MR (16 phases/beat) was imaged with a 7T scanner. Subsequently, we measured RV pressure (RVP) via right internal jugular vein and dissected trabeculae (length = 1.45±0.07 mm, width = 334±27 μm, thickness = 114±6 μm) from RVs. We calculated weight ratio of RV free wall to left ventricle (LV) by RV/(LV+septum). Trabeculae were electrically stimulated with 2-s stimulus intervals, and force was measured using a silicon strain gauge (0.7 mM extracellular Ca2+, 24°C). To determine contractile properties of RV muscle, dF/dt was calculated. Using CMR imaging, we measured RV ejection fraction (RVEF) and RV longitudinal strain (RVLS). To modulate RVP, we intravenously injected 5 nmol endothelin-1 (ET-1) and again measured RVEF and RVLS.

Results

MCT-rats showed higher systolic RVP (62.5±16.6 vs. 25.9±1.86 mmHg, p<0.01) and higher weight ratio of RV (0.60±0.03 vs. 0.28±0.02, p<0.05). In CMR imaging, MCT-rats showed lower RVEF (36.1±11.2 vs. 64.8±8.4%, p<0.001) and lower RVLS (−18±9 vs. −30±1%, p<0.05). In trabeculae from RVs, MCT-rats showed lower developed force and lower dF/dt (p<0.01). Correlation between RVLS and dF/dt was higher (n=20, r=0.53, p<0.05) than that between RVEF and dF/dt (r=0.24). In addition, RVLS and dF/dt had already been decreased in 5 MCT-rats with relatively preserved RVEF (>50%), suggesting that RVLS decreases earlier than RVEF in MCT-rats. Ten minutes after the injection of ET-1, RVP was increased from 49.4±7.9 to 57.9±6.4 mmHg in MCT-rats (n=6). In MCT-rats with preserved RVEF and decreased RVLS, the increase in RVP chiefly decreased RVEF while it did not change RVLS and RVEF in Ctr-rats, meaning that RV functional reserve had been decreased in MCT-rats. In trabeculae, developed force and dF/dt were increased after the addition of 0.1 μM ET-1 in MCT- (n=11, p<0.01) and Ctr-rats (n=4, p<0.01).

Conclusion

These results suggest that in rats with PAH, RVLS obtained from CMR can estimate RV functional reserve earlier and more accurately than RVEF. Therefore, RV strain with CMR may become an important parameter to assess RV functional reserve in patients with PAH.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Young Scientists

Ca2+ loading within mitochondria affects arrhythmogenesis in rat right ventricular hypertrophy

Introduction

Delayed afterdepolarizations (DADs) causes triggered arrhythmias, and intracellular Ca2+ (Cai) waves play important roles in the formation of DADs. It remains unclear, however, whether Ca2+ loading within mitochondria affects arrhythmogenesis in right ventricular (RV) hypertrophy.

Purpose

We focused on the properties of Cai wave propagation, investigating whether changes in Ca2+ loading within mitochondria affects arrhythmogenesis in a rat model of RV hypertrophy.

Methods

Rats were given a subcutaneous injection of 60 mg/kg monocrotaline (MCT-rats) or solvent (Ctr-rats). Four weeks after the injection, trabeculae were dissected from RVs. Force was measured using a silicon strain gauge, membrane potential using a microelectrode, Cai using microinjected fura-2 and a CCD camera, and ROS production using 2',7'-dichlorofluorescein (DCF) fluorescence. Cai waves and arrhythmias were induced by electrical stimulation (24°C). To change Ca2+ loading within mitochondria, Ru360 (10 μM), a mitochondrial calcium uptake inhibitor, was added.

Results

MCT-rats showed lower survival rate (p=0.075), higher RV systolic pressure (48.8±4.6 vs 21.3±6.5 mmHg), and heavier weight ratio of RV free wall to left ventricle (LV) (0.44±0.03 vs 0.25±0.04). MCT-rats showed a wider action potential (APD90, 320±20 vs 205±11 ms), a higher diastolic Cai (177±20 vs 110±8 nM), and faster and larger Cai waves (p<0.01). The velocity and amplitude of Cai waves were correlated with the diastolic Cai in Ctr- and MCT-rats. The velocity of Cai waves in MCT-rats was higher than that in Ctr-rats at the given amplitude of Ca2+ waves (p<0.01). The velocity and amplitude of Cai waves was linearly correlated with the amplitude of DADs in Ctr- and MCT-rats. Ru360 decreased the inducibility of arrhythmias in some trabeculae (MCT-A-rats, n=7), while it did not change it or it inversely increased it in the others (MCT-B-rats, n=11). RV systolic pressure in MCT-A-rats was higher than that in MCT-B-rats (62.2±6.0 vs 41.0±5.2 mmHg), and the weight ratio of RV to LV in MCT-A-rats was higher than that in MCT-B-rats (0.51±0.04 vs 0.41±0.03). The changes in Cai wave propagation velocity after the addition of Ru360 was inversely correlated with the weight ratio of RV to LV (r=−0.64) and the RV pressure (r=−0.60, n=7), suggesting that under the condition of severe RV hypertrophy due to higher RV pressure, reduction of Ca2+ within mitochondria results in a decrease in the velocity of the Cai waves, thereby improving of arrhythmias. In the presence of Ru360, DCF oxidation rate was decreased during 0.5 or 2.5 Hz electrical stimulation (n=5, p<0.05).

Conclusions

In RV hypertrophy, acceleration of Cai waves occurs due to an increase in diastolic Cai and an increase in Ca2+ sensitivity of the SR Ca2+ release channels, thereby causing arrhythmias. In more severe RV hypertrophy, Ca2+ within mitochondria may also be involved in arrhythmogenesis probably through an increase in ROS production.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Scientific Research (C) from Japan Society for the Promotion of Science

4096Additive effects of exercise training upon cognitive function in regular red wine consumers compared to abstainers

Background

Although regular red wine (RW) consumption and physical exercise (PE) exert cardiovascular protection a possible aditive effect of both is unknown, especially regarding cognition.

Purpose

To investigate the effects of supervised PE upon cognitive function in regular RW consumers compared to abstainers (Abs)

Methods

Cognitive function was assessed by functional Cerebral Magnetic Resonance Image (fMRI) through Stroop Color Word test (Stroop) for executive function and 2-back for working memory as well as neuropsychological tests (trails A, B and Stroop1). Seventy three healthy males, aged 59±5.9 (SD) years were divided into 4 groups: 37 Abs (17 with PE, 20 without) and 36 RW drinkers (17 with PE, 19 without) and then were randomized in the pre-PE phase, either to supervised PE for 3 months, 3x week/1h duration or no PE. Cardiopulmonary exercise test (CET) was performed before and after interventions. Plasma lipids and glucose also were measured.

Results

Drinkers ingested 19.8±10.3 (SD) gr of ethanol/day as RW for an average of 26.1±15.7 years and did not change their habits during the study period. In pre-PE phase RW drinkers showed lower execution times than Abs in neurophsychological tests (trails A and B and Stroop1) and higher accuracy in the 2-back test in fMRI (p<0.05 for both). Furthermore, in post intervention phase, RW consumers with PE showed a trend towards improvement in executive function (Stroop: % accuracy 92.5±9.2 vs 95.6±5.0, p=0.05) and reduction in execution time (21.9±6 vs 19±3.4; p=0.049) as well as in neuropsychological Stroop-2 (p<0.05).In parallel there were no changes in activated cerebral áreas in either group after PE. However, there was a negative correlation between peak VO2 and activated brain areas by fMRI (Expert Analysis Tool based on the Generalized Linear Model; p<0.05) in both Abs and drinkers.

In contrast, there were no significant changes in any cognition test among abstainers regardless of PE; also there were no changes in metabolic profile. PE induced significant increments in peak VO2 in all PE groups (p<0.05).

fMRI BOLD sign during 2-back test

Conclusion

Physical exercise induced further improvement in executive function and working memory in long term RW drinkers, while no effects occurred in abstainers. Such effect was correlated with global fitness, as assessed by peak VO2.

Acknowledgement/Funding

Fundação de Amparo à Pesquisa do Estado de São Paulo; Banco Bradesco SA

Abstract OT2-05-02: International retrospective cohort study of locoregional and systemic therapy in oligometastatic breast cancer (OLIGO-BC1)

Breast cancer (BC) is so-called “systemic disease”, because disseminated cancer cells in bone marrow and blood are detected even in early BC patients. Despite adjuvant therapy and postoperative radiation therapy, patients with triple negative BC and Luminal B-like BC often relapse early and systemic therapy is the only way to control disease progression. On the other hand, some BC patients relapse several years later. In such patients, oligometastases are occasionally diagnosed, because metastatic cancer cells are slowly growing and indolent. Oligometastatic BC is defined as low volume metastatic disease with limited number and size of metastatic lesions (up to five and not necessarily in the same organ). This definition is proposed in the Advanced Breast Cancer guidelines that are developed as a joint effort from European School of Oncology and European Society of Medical Oncology. Several retrospective studies demonstrated survival benefit of locoregional therapy in addition to systemic therapy. Locoregional therapy consisted of surgical resection, radiation therapy, ablation therapy, etc. However, it remains unclear about survival benefit of combined therapy in oligometastatic BC. To improve the standard of cancer treatment through the cooperate studies on more effective therapeutic strategies based on drugs, surgery and/or radiotherapy, Federation of Asian Clinical Oncology (FACO) was established in 2012 by Chinese Society of Clinical Oncology (CSCO), Korean Society of Medical Oncology (KSMO) and Japan Society of Clinical Oncology (JSCO). Thus, FACO conducted a retrospective cohort study on oligometastatic BC. The primary endpoint is to compare the estimated 5-year overall survival (OS) of oligometastatic BC patients treated with combined therapy and systemic therapy alone. To hypothesize that combined therapy has more advantage of OS in oligometastatic BC, the 5-year OS rates are expected to be 50% and 40%, respectively. The estimated sample size is calculated to be the number of 698 cases (349 cases in each group) needed to prove the superiority of survival with a two-sided type I error rate of 5% and a statistical power of 80%. Case registry opened in February 2018 and will close in January 2019. We planned to register 700 cases, i.e., 234 cases each from investigators of CSCO, KSMO and JSCO. Update information will be discussed.

Citation Format: Imoto S, Futamura M, Toi M, Fujiwara Y, Ueno T, Im Y-H, Im S-A, Ahn SG, Lee JE, Park YH, Wang K, Kitagawa Y, Nishiyama M. International retrospective cohort study of locoregional and systemic therapy in oligometastatic breast cancer (OLIGO-BC1) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-05-02.

Potent inhibition of angiotensin AT1 receptor signaling by RGS8: importance of the C-terminal third exon part of its RGS domain

R4/B subfamily RGS (regulator of G protein signaling) proteins play roles in regulation of many GPCR-mediated responses. Multiple RGS proteins are usually expressed in a cell, and it is difficult to point out which RGS protein species are functionally important in the cell. To evaluate intrinsic potency of these RGS proteins, we compared inhibitory effects of RGS1, RGS2, RGS3, RGS4, RGS5, RGS8 and RGS16 on AT1 receptor signaling. Intracellular Ca(2+) responses to angiotensin II were markedly attenuated by transiently expressed RGS2, RGS3 and RGS8, compared to weak inhibition by RGS1, RGS4, RGS5 and RGS16. N-terminally deleted RGS2 (RGS2 domain) lost this potent inhibitory effect, whereas RGS domains of RGS3 and RGS8 showed strong inhibition similar to those of the full-length proteins. To investigate key determinants that specify the differences in potency, we constructed chimeric domains by replacing one or two of three exon parts of RGS8 domain with the corresponding part of RGS5. The chimeric RGS8 domains containing the first or the second exon part of RGS5 showed strong inhibitory effects similar to that of wild type RGS8, but the chimeric domain with the third exon part of RGS5 lost its activity. On the contrary, replacement of the third exon part of RGS5 with the corresponding residues of RGS8 increased the inhibitory effect. The role of the third exon part of RGS8 domain was further confirmed with the chimeric RGS8/RGS4 domains. These results indicate the potent inhibitory activity of RGS8 among R4/B subfamily proteins and importance of the third exon.

Effects of gold thioglucose treatment on central corticotrophin-releasing hormone systems in mice

Systemic administration of gold thioglucose (GTG) causes a hypothalamic lesion that extends from the ventral part of the ventromedial hypothalamus (VMH) to the dorsal part of the arcuate nucleus (ARC), resulting in hyperphagia and obesity in mice. In the present study, we used in situ hybridisation histochemistry to explore the effects of GTG on the central corticotrophin-releasing hormone (CRH) system, which regulates feeding and energy homeostasis. Type 2 CRH receptor (CRHR-2) mRNA expression decreased by 40% at 8 weeks in the VMH and by 40-60% at 2 and 8 weeks in the ARC after GTG injection. By contrast, CRHR-2 mRNA expression in the hypothalamic paraventricular nucleus (PVN) and lateral septum was unchanged. Urocortin (Ucn) 3 mRNA expression in the perifornical area and medial amygdala decreased, whereas CRH mRNA expression in the PVN increased at 2 and 8 weeks after GTG injection. Ucn 1 mRNA expression in the Edingher-Westphal nucleus and Ucn 2 mRNA expression in the PVN were unchanged. Because Ucn 3 is an anorexigenic and a possible endogenous ligand for VMH CRHR-2, our results suggest that decreased Ucn 3 expression and decreased VMH CRHR-2 expression contribute, in part, to GTG-induced hyperphagia and obesity. To determine whether VMH CRHR-2 mediates the anorexigenic effects of Ucn 3, Ucn 3 was administered i.c.v. and food intake was measured 8 weeks after GTG treatment. Ucn 3 decreased cumulative food intake on days 4-7 after surgery compared to i.c.v. administration of vehicle in control mice. By contrast, the anorexigenic effects of i.c.v. Ucn 3 were abolished in GTG-treated mice. Taken together, our results indicate that the Ucn 3 pathway, which innervates the VMH, is involved in appetite regulation via CRHR-2. It remains to be determined whether CRHR-2 in the ARC has additional roles in appetite regulation by Ucn 3.

Coamplification of cyclin-d, hst-1 and int-2 genes is a good biological marker of high malignancy for human esophageal carcinomas

In order to elucidate whether the amplification of cyclin D gene, hst-1 and int-2 genes might be a good biological marker of high malignancy for human esophageal carcinomas, we analyzed the coamplification of these genes by slot blot analysis using DNAs from formalin fixed paraffin embedded tissues of 18 dysplastic lesions, 100 primary esophageal carcinomas after surgical resection and 18 metastatic carcinomas of esophagus taken at autopsy. No amplification was detected in dysplasia, while it was detected in 41 cases (41%) of primary tumors and 100% of metastatic carcinomas, respectively. The amplification of these genes correlated to tumor staging and depth of tumor invasion. Moreover, the prognosis of patients with gene amplification was poorer than those without gene amplification. Interestingly, distant metastasis and local recurrence, were often observed in cases with gene amplification. These results indicate that amplification of cyclin D, hst-1 and int-2 genes might play an important role for tumor progression and patient prognosis for human esophageal carcinomas.

Immunohistochemical detection of cripto-1, amphiregulin and transforming growth-factor-alpha in human gastric carcinomas and intestinal metaplasias

The expression and localization of cripto-1 (CR-1), amphiregulin (AR) and transforming growth factor alpha (TGFalpha) were assessed by immunocytochemistry in 37 primary human gastric tumors, 30 noninvolved gastric mucosa samples that were adjacent to carcinoma but exhibited intestinal metaplasia and 37 adjacent, noninvolved gastric mucosa samples. Seventeen (46%), nineteen (51%) and twenty-one (57%) carcinomas showed staining for CR-1, AR and TGFalpha, respectively; whereas sixteen (53%), eight (26%) and five (17%) intestinal metaplasias were reactive with the anti-CR-1, anti-AR and anti-TGFalpha antibodies, respectively. In contrast, none of the normal, noninvolved gastric mucosa samples reacted with the TGFalpha antibody and only 1 (3%) of these samples showed weak staining with the anti-CR-1 antibody. However, 8 (21%) of the normal gastric mucosa samples showed moderate levels of staining with the AR antibody. Within the carcinomas, there was a slight trend for association between TGFalpha and CR-1 expression (p<0.05), but no correlation was found between epidermal growth factor receptor and CR-1 expression. Staining for p53 was observed in 26 (70%) of the carcinomas, 3 (10%) intestinal metaplasias and none of the gastric mucosa samples. This data demonstrate that CR-1, like TGFalpha, may be a tumor marker for a subset of gastric carcinomas in addition to being an important factor in the early stages of gastric cancer development.

Stereoselective Reduction of α-Keto Ester and α-Keto Amide with Marine Actinomycetes, Salinispora strains, as Novel Biocatalysts

To clarify the potential ability of marine actinomycetes as biocatalysts, the stereoselective reduction of α-keto esters and α-keto amide using Salinispora arenicola and Salinispora tropica was tested. The reduction of ethyl pyruvate and ethyl 2-oxobutanoate by S. tropica gave corresponding alcohol with high conversion ratio and in high e.e. (96% e.e. ( S) and 99% e.e. ( S), respectively). In the presence of l-glutamate as an additive, the reduction of ethyl pyruvate by S. tropica afforded the corresponding ( S)-ethyl lactate with >99% e.e. Furthermore, 2-chlorobenzoylformamide was reduced by S. tropica to the corresponding ( R)-2-chloromandelamide with high conversion ratio and excellent enantioselectivity (>99% e.e.). Thus, it was found that marine actinomycetes, Salinispora strains, had high ability for the stereoselective reduction of carbonyl compounds as useful biocatalysts.

Drugs and lifestyle for the treatment and prevention of coronary artery disease: comparative analysis of the scientific basis

In this article, we compare two strategies for atherosclerosis treatment: drugs and healthy lifestyle. Statins are the principal drugs used for the treatment of atherosclerosis. Several secondary prevention studies have demonstrated that statins can significantly reduce cardiovascular events including coronary death, the need for surgical revascularization, stroke, total mortality, as well as fatal and non-fatal myocardial infarction. These results were observed in both men and women, the elderly, smokers and non-smokers, diabetics and hypertensives. Primary prevention studies yielded similar results, although total mortality was not affected. Statins also induce atheroma regression and do not cause cancer. However, many unresolved issues remain, such as partial risk reduction, costs, several potential side effects, and long-term use by young patients. Statins act mainly as lipid-lowering drugs but pleiotropic actions are also present. Healthy lifestyle, on the other hand, is effective and inexpensive and has no harmful effects. Five items are associated with lower cardiac risk: non-smoking, BMI ≤25, regular exercise (30 min/day), healthy diet (fruits, vegetables, low-saturated fat, and 5-30 g alcohol/day). Nevertheless, there are difficulties in implementing these measures both at the individual and population levels. Changes in behavior require multidisciplinary care, including medical, nutritional, and psychological counseling. Participation of the entire society is required for such implementation, i.e., universities, schools, media, government, and medical societies. Although these efforts represent a major challenge, such a task must be faced in order to halt the atherosclerosis epidemic that threatens the world.

Potent and selective inhibition of angiotensin AT1 receptor signaling by RGS2: roles of its N-terminal domain

Emerging evidence indicates that R4/B subfamily RGS (regulator of G protein signaling) proteins play roles in functional regulation in the cardiovascular system. In this study, we compared effects of three R4/B subfamily proteins, RGS2, RGS4 and RGS5 on angiotensin AT1 receptor signaling, and investigated roles of the N-terminus of RGS2. In HEK293T cells expressing AT1 receptor stably, intracellular Ca(2+) responses induced by angiotensin II were much more strongly attenuated by RGS2 than by RGS4 and RGS5. N-terminally deleted RGS2 proteins lost this potent inhibitory effect. Replacement of the N-terminal residues 1-71 of RGS2 with the corresponding residues (1-51) of RGS5 decreased significantly the inhibitory effect. On the other hand, replacement of the residues 1-51 of RGS5 with the residues 1-71 of RGS2 increased the inhibitory effect dramatically. Furthermore, we investigated functional contribution of N-terminal subdomains of RGS2, namely, an N-terminal region (residues 16-55) with an amphipathic α helix domain (the subdomain N1), a probable non-specific membrane-targeting subdomain, and another region (residues 56-71) between the α helix and the RGS box (the subdomain N2), a probable GPCR-recognizing subdomain. RGS2 chimera proteins with the residues 1-33 or 34-52 of RGS5 showed weak inhibitory activity, and either of RGS5 chimera proteins with residues 1-55 or 56-71 of RGS2 showed strong inhibitory effects on AT1 receptor signaling. The present study indicates the essential roles of both N-terminal subdomains for the potent inhibitory activity of RGS2 on AT1 receptor signaling.

Characteristics of paediatric patients with 2009 pandemic influenza A(H1N1) and severe, oxygen-requiring pneumonia in the Tokyo region, 1 September-31 October 2009

Few reports describe the features of 2009 pandemic influenza A(H1N1) pneumonia in children. We retrospectively reviewed 21 consecutive children admitted to hospital from September to October 2009 in the Tokyo region. The diagnosis of 2009 pandemic influenza A(H1N1) virus infection was based on positive results of real-time RT-PCR or rapid influenza antigen test. All patients were hospitalised for pneumonia with respiratory failure and severe hypoxia. The median interval from onset of influenza symptoms to admission was 14 hours (range: 5-72 hours) and the median interval from the onset of fever (≥38 degrees C) to hospitalisation was 8.5 hours (range: 0-36 hours). All patients required oxygen inhalation. Four patients required mechanical ventilation. Chest radiography revealed patchy infiltration or atelectasis in all patients. Antiviral agents and antibiotics were administrated to all patients. Antiviral agents were administered to 20 patients within 48 hours of influenza symptom onset. No deaths occurred during the study period. Paediatric patients with this pneumonia showed rapid aggravation of dyspnoea and hypoxia after the onset of influenza symptoms.

Characteristics of paediatric patients with 2009 pandemic influenza A(H1N1) and severe, oxygen-requiring pneumonia in the Tokyo region, 1 September–31 October 2009

Binary file ES_Abstracts_Final_ECDC.txt matches

Optimal patient selection for CPT-11 chemotherapy in colorectal cancer: Quantitative prediction of tumor response and overall survival using expression data of novel marker genes

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Background: Unlike the toxicity, none of the critical prediction markers of CPT-11 efficacy has been validated to date. With a hypothesis that expression analysis of a set of the key drug sensitivity genes could allow us to predict the therapeutic response, we identified potent marker genes for CPT-11 in in vitro, conducted this prospective study attempting to develop a prediction formula of efficacy using the expression data (2006 ASCO, 2006 ESMO), and demonstrated the latest prediction formula of the best tumor response (BTR), time to treatment failure (TTP), and the overall survival after CPT-11 chemotherapy (OS). Methods: Seven genes identified as possible marker genes for CPT-11 (SN-38)- AMD1, CTSC, EIF1AX, FLJ13089 , DDX54, PTPN2, and TBX3-, and 5 other possible marker genes (ABCG2, CYP3A4, MGMT, POR, and TOP2A) that had already been known as drug sensitivity determinants and selected by our in vitro screening process, were studied. CPT-11 was intravenously administered on Days 1, 8, and 15, every 4 weeks in chemo-naive patients with stage IV colorectal cancer after palliative operation. Tumor samples were collected at surgery and tumor response was evaluated by RECIST. Results: All of the 44 enrolled patients were assessable for BTR (% of initial tumor size), TTP (day), and OS (day) in the clinical study, and we successfully developed the best linear model for each, which converted the quantified expression data of the 7 selected genes into objective BTR, TTP, and OS. We used 20, 16, and 15 tumor specimens and constructed potent prediction formulae for BTR (r=0.9420), TTP (r=0.7103), and OS (r=0.8406), respectively. Utility-confirmation analyses using another 16, 10, 13 clinical samples appeared to show that the formulae could predict BTR (r=0.6491, p=0.007) and OS (r=0.7947, p=0.011). We also fixed the best linear models using 5 other known marker genes, but they had less advantage in prediction. Conclusions: Despite limited data, our developed formulae using the 7 novel genes would provide advantages in prediction of individual response to CPT-11. Based on the positive results of this study, we have initiated a large scale validation study of the formula.

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Randomized phase II/III study of docetaxel/S-1 (DS-1) versus CDDP/5FU (FUP) in advanced or recurrent gastric cancer: Updated phase II results

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Background: Our previous single arm phase II trial demonstrated that the combination of DS-1 was one of the most powerful candidates to become a standard regimen for metastatic gastric cancer (K. Yoshida, et al: Clin Cancer Res 2006). This trial evaluated DS-1 and FUP in advanced or recurrent gastric cancer, and the primary objective of the phase II part was to evaluate activity and safety of the 2 regimens. Methods: Patients with advanced or recurrent gastric cancer, who had not received any chemotherapy except one regimen (not including taxanes), were eligible for this trial. Patients were randomized to either: DS-1, intravenous administration of 40 mg/m2 docetaxel on Day1 and oral administration of 80–120 mg/m2/day S-1 on Days 1 to 14 every 3 weeks, or FUP, intravenous continuous administration of 800 mg/m2/day 5-FU on Day 1 to 5 and intravenous administration of 80 mg/m2/day CDDP on Day 2 every 4 weeks. Results: Between June 2005 and August 2008, forty-nine of 54 patients (ECOG PS 0–2) were randomized to DS-1 (n=24) or FUP (n=25). Response rates (CR+PR) assessed by RECIST were 88.3% (CI;62.6–95.3) vs 52.0% (CI; 31.3–72.2, P=0.032), median times to treatment failure (TTF) were 122 days (CI; 75.2–168.8) vs 85 days (CI;67.9–102.1, P=0.003), median progression free survivals (PFS) were 198 days (CI;117.8–278.4) vs 105 days (CI;90.3–119.7, P=0.066). Median overall survival times (MSTs) were 369 days (CI; 359.6–378.4) vs 371 days (CI; 297.2- 444.8, P=0.281), but as of today, 14 pts (8 in DS-1 and 6 in FUP) are still alive. Grade 3/4 adverse events assessed by CTCAE v3.0 occurring in ≥20% patients, were neutropenia (58.3% vs 28.0%), nausea (4.2% vs 20.0%), leucopenia (33.0% vs 4.0%), fatigue (0% vs 20.0%) and anorexia (8.3% vs 32.0%). All treatment-related adverse events were resolved and no toxic death was reported. Conclusions: DS-1 significantly improved the RR and TTF in advanced or recurrent gastric cancer patients. To clarify the survival benefit, a phase III continuation of the study is in preparation.

No significant financial relationships to disclose.

Human mismatch repair gene, MLH1, is transcriptionally repressed by the hypoxia-inducible transcription factors, DEC1 and DEC2

Tumor hypoxia has been reported to cause a functional loss in DNA mismatch repair (MMR) system as a result of downregulation of MMR genes, although the precise molecular mechanisms remain unclear. In this study, we focused on the downregulation of a key MMR gene, MLH1, and demonstrated that hypoxia-inducible transcription repressors, differentiated embryo chondrocytes (DEC1 and 2), participated in its transcriptional regulation via their bindings to E-box-like motif(s) in MLH1 promoter region. In all cancer cell lines examined, hypoxia increased expression of DEC1 and 2, known as hypoxia-inducible genes, but decreased MLH1 expression in an exposure time-dependent manner at both the mRNA and protein levels. Co-transfection reporter assay revealed that DEC1 and, to greater extent, DEC2 as well as hypoxia-repressed MLH1 promoter activity. We further found that the action was remarkably inhibited by trichostatin A, and identified a possible DEC-response element in the MLH1 promoter. In vitro electrophoretic gel mobility shift and chromatin immunoprecipitation assays demonstrated that DEC1 or 2 directly bounds to the suggested element, and transient transfection assay revealed that overexpression of DEC2 repressed endogenous MLH1 expression in the cells. Hypoxia-induced DEC may impair MMR function through repression of MLH1 expression, possibly via the histone deacethylase-mediated mechanism in cancer cells.

Up-regulation of CXC chemokines and their receptors: implications for proinflammatory microenvironments of ovarian carcinomas and endometriosis

Molecular abnormalities in the epithelial cells of endometriosis and their relevance to carcinogenesis of the ovary have been well studied. On the other hand, the differences of proinflammatory microenvironments between endometriosis and ovarian carcinomas have not been well documented yet. In this study, the expression patterns of CXC chemokines (IL-8, ENA-78, GRO-alpha, I-TAC, Mig, and SDF-1) and their receptors (CXCR2, CXCR3, and CXCR4) were compared among 12 ovarian carcinomas, 8 endometriosis, and 6 normal ovaries using quantitative reverse transcriptase polymerase chain reaction and immunohistochemistry. The CXCR3-mediated signaling in ovarian carcinoma cells in vitro was also investigated. In quantitative reverse transcriptase polymerase chain reaction, ENA-78 was up-regulated both in endometriosis and carcinomas, whereas I-TAC was detected exclusively in carcinomas. CXCR3 was up-regulated both in carcinomas and endometriosis. However, immunohistochemical studies revealed that the localization of CXCR3 in carcinomas was distinctively different from that in endometriosis. In carcinoma-endometriosis coexisting cases, CXCR3-positive lymphocytes in benign lesions decreased in proportion as CXCR3-positive tumor cells replaced the tissues. CXCR3 was also detected in ovarian carcinoma cell lines in vitro. Administration of interferon gamma (IFN-gamma)-inducible chemokines induced extracellular signal-regulated kinase phosphorylation in these carcinoma cells. The results indicated that CXC chemokines might contribute to the progression of ovarian carcinomas and endometriosis in different manners. Aberrant expression of IFN-gamma-inducible chemokines and CXCR3 in carcinoma cells in association with reduced CXCR3-positive immune cells raised the possibility that IFN-gamma-inducible chemokines might not exert effective antitumor immune responses but that they might work in favor of tumor progression.

Indocyanine green fluorescence angiography for intraoperative assessment of blood flow: a feasibility study

OBJECTIVE

To introduce our preliminary experience with indocyanine green (ICG) fluorescence angiography for the assessment of lower leg bypasses.

METHODS

1ml of 0.5% indocyanine green was intravenously injected in 9 patients with PAD who underwent paramalleolar artery bypass using saphenous vein grafts. A newly developed near-infrared camera system (PDE; Hamamatsu Photonics K.K. Hamamatsu, Japan) was used for this study.

RESULTS

ICG fluorescence angiography was performed without any adverse events. Fluorescence images of ICG angiography could be viewed as real-time images of the angiography in eight patients, while one patient underwent graft revision with the absence of fluorescence in ICG angiography.

CONCLUSION

ICG fluorescence angiography is clinically feasible and may help surgeons assess the quality of lower leg bypasses.

CD151 dynamics in carcinoma-stroma interaction: integrin expression, adhesion strength and proteolytic activity

A member of tetraspanin CD151 is a scaffold protein of laminin-binding integrins and it plays an important role in stable interaction between cells and basement membrane. Although the upregulation of CD151 in tumor cells is thought to accelerate tumor invasion and metastasis, detailed pathological investigation on CD151 and its association with integrins has not been well documented, yet. In the present study, we showed that the expression levels of CD151 and its associated integrin subunits in epidermal carcinoma cell HSC5 were higher than those in immortalized epidermal cell HaCaT. By the stimulation of epidermal growth factor, CD151 was dissociated from cell surface and dispersed in the cytoplasm, and alpha3beta1 integrin was concomitantly internalized. To understand the significance of CD151 in tumor cell dynamics, CD151 in HSC5 was knocked down (HSC5(CD151-)), and the expression of integrin subunits and matrix metalloproteinases (MMPs) were investigated. In HSC5(CD151-), striking morphological alteration on Matrigel and laminin, and cytoskeletal rearrangements were demonstrated. alpha3beta1 integrin was internalized in part, and alpha6beta4 integrin was re-distributed from basal site to cell periphery. Quantitative RT-PCR, Western blot and zymography revealed that the expression levels of MMP2, MMP7 and MMP9 were markedly downregulated in HSC5(CD151-). Immunoprecipitation assay demonstrated that MMP7 was co-immunoprecipitated with CD151. In double stainings, MMP7 was colocalized with CD151 at the leading edge of lamellipodia under migratory status. These results elucidated the importance of CD151 as one of the key molecules for integrin-dependent carcinoma-stroma interaction. It is indicated that CD151 might contribute not only to cell stabilization by associating with adhesion complexes but also to cell migration by inducing integrins re-localization and MMPs production.

Pharmacogenomic (PG) analysis for prediction of individual response to paclitaxel in 5-FU-refractory metastatic gastric cancer: Prediction formula of tumor response using novel marker genes and genotypes associated with the toxicity

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Background: Taxanes offer hope for improving outcomes of metastatic gastric cancer patients including 5-FU failure cases, but the response remarkably varies among patients. We conducted this prospective PG study for paclitaxel monotherapy to develop a prediction formula of efficacy and to identify potent genetic markers of toxicity. Methods: Paclitaxel was intravenously given on Days 1, 8, and 15, every 4 weeks in 5-FU failure metastatic gastric cancer patients with typical eligibility criteria. Tumor and blood samples were collected before the initial paclitaxel administration for PG. PK analysis was done on day 1 of cycle 1. Tumor response and toxicity were evaluated by RECIST and CTCAE, respectively. Results: Forty-nine pts were enrolled, and up to date, 48 and 44 pts have been determined for worst toxicity and best tumor response, respectively. Observed response rate was 27.3% (12/44), and common grade 3/4 toxicities were neutropenia (31.3%) and leucopenia (20.8%). PG analysis demonstrated that CYP2C8*1C (w/v=27, v/v=5) and CYP2C8 -411T>C (w/v=24, v/v=10) were weakly associated with grade 3/4 leucopenia (p=0.087 and 0.092), and CYP2C8 IVS7+49T> A (w/v=9, v/v=6) might correlate with grade 3/4 anemia (p=0.039), although none of them correlated with any PK parameter. We identified 4 novel potent marker genes (SEPT5, MARN2, PER3, and PISA3) for paclitaxel efficacy in vitro through microarray expression analysis, and then successfully developed the best linear models, which converted the quantified expression data into objective clinical response, in terms of best tumor response (r=0.985, AICS=-5.269) and overall survival (r=0.980, AICS=6.953), using 15 and 13 data sets of gene expression and clinical response, respectively. At present, utility-confirmation analyses using other clinical samples appeared to show that the formulae could accurately predict tumor response. Conclusions: Polygenetic strategies using several known polymorphisms for toxicity and a prediction formula using 4 novel genes for efficacy would be of predictive value for individual response to paclitaxel.

No significant financial relationships to disclose.

Phosphorylation of Ser166 in RGS5 by protein kinase C causes loss of RGS function

RGS5 is a member of regulators of G protein signaling (RGS) proteins that attenuate heterotrimeric G protein signaling by functioning as GTPase-activating proteins (GAPs). We investigated phosphorylation of RGS5 and the resulting change of its function. In 293T cells, transiently expressed RGS5 was phosphorylated by endogenous protein kinases in the basal state. The phosphorylation was enhanced by phorbol 12-myristate 13-acetate (PMA) and endothelin-1 (ET-1), and suppressed by protein kinase C (PKC) inhibitors, H7, calphostin C and staurosporine. These results suggest involvement of PKC in phosphorylation of RGS5. In in vitro experiments, PKC phosphorylated recombinant RGS5 protein at serine residues. RGS5 protein phosphorylated by PKC showed much lower binding capacity for and GAP activity toward Galpha subunits than did the unphosphorylated RGS5. In cells expressing RGS5, the inhibitory effect of RGS5 on ET-1-induced Ca(2+) responses was enhanced by staurosporine. Mass spectrometric analysis of the phosphorylated RGS5 revealed that Ser166 was one of the predominant phosphorylation sites. Substitution of Ser166 by aspartic acid abolished the binding capacity to Galpha subunits and the GAP activity, and markedly reduced the inhibitory effect on ET-1-induced Ca(2+) responses. These results indicate that phosphorylation at Ser166 of RGS5 by PKC causes loss of the function of RGS5 in G protein signaling. Since this serine residue is conserved in RGS domains of many RGS proteins, the phosphorylation at Ser166 by PKC might act as a molecular switch and have functional significance.

Evaluation of different bonded investments for dental titanium casting

The properties of several different investments were investigated including phosphate bonded, magnesia bonded, and alumina cement investments. Measurements included the setting expansion, thermal expansion, and compressive strength of investments, as well as the tensile strength, elongation, Vickers hardness (VHN) and surface roughness of titanium castings. For phosphate bonded investment, the setting expansion after being mixed with its own mixing solution was 2.10%, which was larger than the other investments; the thermal expansion was -0.25% at 200 degrees C, the compressive strength 14 and 5 MPa after heating. For titanium cast in phosphate bonded investment, the hardness on its top surface was 655 Hv, the tensile strength was 379 MPa, the elongation was 19.4%, and the surface roughness was 2.29 microm. Athough the thermal expansion of phosphate bonded investment is small, the setting expansion is large enough to compensate for the shrinkage of titanium castings. As its thermal expansion at T >/= 600 degrees C was constant and its heating-cooling cycle was almost reversible, these two properties can reduce the thermal shock and thus avoid cracking of the investment.

Pathophysiology of tumor neovascularization

Neovascularization is essential to the process of development and differentiation of tissues in the vertebrate embryo, and is also involved in a wide variety of physiological and pathological conditions in adults, including wound repair, metabolic diseases, inflammation, cardiovascular disorders, and tumor progression. Thanks to cumulative studies on vasculature, new therapeutic approaches have been opened for us to some life-threatening diseases by controlling angiogenesis in the affected organs. In cancer therapy, for example, modulation of factors responsible for tumor angiogenesis may be beneficial in inhibiting of tumor progression. Several antiangiogenic approaches are currently under preclinical trial. However, the mechanisms of neovascularization in tumors are complicated and each tumor shows unique features in its vasculature, depending on tissue specificity, angiogenic micromilieu, grades and stages, host immunity, and so on. For better understanding and effective therapeutic approaches, it is important to clarify both the general mechanism of angiogenic events and the disease-specific mechanism of neovascularization. This review discusses the general features of angiogenesis under physiological and pathological conditions, mainly in tumor progression. In addition, recent topics such as contribution of the endothelial progenitor cells, tumor vasculogenic mimicry, markers for tumor-derived endothelial cells and pericytes, and angiogenic/angiostatic chemokines are summarized.

Spin Triplet Superconducting State due to Broken Inversion Symmetry in Li(2)Pt(3)B

We report (11)B and (195)Pt NMR measurements in noncentrosymmetric superconductor Li(2)Pt(3)B. We find that the spin susceptibility measured by the Knight shift remains unchanged across the superconducting transition temperature T(c). With decreasing temperature (T) below T(c), the spin-lattice relaxation rate 1/T(1) decreases with no coherence peak and is in proportion to T3. These results indicate that the Cooper pair is in the spin-triplet state and that there exist line nodes in the superconducting gap function. They are in sharp contrast to those in the isostructural Li(2)Pd(3)B which is a spin-singlet, s-wave superconductor, and are ascribed to the enhanced spin-orbit coupling due to the lack of spatial inversion symmetry. Our finding points to a new paradigm where exotic superconductivity arises in the absence of electron-electron correlations.

A leptomycin B resistance gene ofSchizosaccharomyces pombeencodes a protein similar to the mammalian P-glycoproteins

Screening for leptomycin B (LMB)-resistant transformants in a gene library constructed in Schizosaccharomyces pombe with the chromosomal DNA of an LMB-resistant mutant of S. pombe and with multicopy plasmid pDB248' as the vector led to the isolation of a gene, named pmd1+, encoding a 1362-amino-acid protein. This protein showed great similarity in amino acid sequence to the mammalian P-glycoprotein encoded by the multidrug resistance gene, mdr, and the Saccharomyces cerevisiae a-factor transporter encoded by STE6. In addition, computer analyses predicted that the protein encoded by pmd1+ formed an intramolecular duplicated structure and each of the halves contained six transmembrane regions as well as two ATP-binding domains, as observed with the P-glycoproteins and the STE6 product. Consistent with this was that S. pombe cells containing the pmd1+ gene on a multicopy plasmid showed resistance not only to LMB but also to several cytotoxic agents. The pmd1 null mutants derived by gene disruption were viable and hypersensitive to these agents. All these data suggest that the pmd1+ gene encodes a protein that is a structural and functional counterpart of mammalian mdr proteins.