Successful left ventricular lead placement by way of an azygos vein for a patient performing cardiac resynchronization therapy implantation with an occluded left subclavian vein: A case report.

Central venous obstruction following pacemaker implantation is not uncommon and can prove challenging in the case of a system upgrade to a cardiac resynchronization therapy pacemaker (CRT-P). We describe the case of a patient who underwent a successful upgrading procedure of a pacemaker to a CRT-P in the presence of an occluded left subclavian vein and superior vena cava, using collateral veins that drained into right atrium.

O- and N-Selective Electrophilic Activation of Allylic Alcohols and Amines in Pd-Catalyzed Direct Alkylation.

Catalytic control of chemoselectivity is crucial in the synthesis of highly functionalized compounds. Although there are reports of efficient chemoselective reactions of alcohols and amines as nucleophiles, there are no reports of the chemoselective activation of alcohols and amines as electrophiles. In this study, highly O- and N-selective electrophilic activation of allylic alcohols and amines was achieved in Pd-catalyzed direct allylic alkylation. Allylamines were inherently more reactive than allylic alcohols (N-selectivity). On the other hand, the addition of catalytic amounts of 9-phenanthreneboronic acid preferentially activated allylic alcohols over allylamines (O-selectivity). Density functional theory (DFT) calculations suggested that the N-selectivity is due to the selective activation of allylic amines with ammonium cations, and boronate formation accelerates the activation of allylic alcohols.

Skeletal muscle mass is associated with glycemic variability in patients with ST-segment elevation myocardial infarction.

Skeletal muscle function has been studied to determine its effect on glucose metabolism; however, its effect on glycemic variability (GV), which is a significant glycemic marker in patients with coronary artery disease, is unknown. The aim of the present study was to elucidate the association between skeletal muscle mass and GV. Two hundred and eight consecutive ST-segment elevation myocardial infarction (STEMI) patients who underwent continuous glucose monitoring to evaluate mean amplitude of glycemic excursion (MAGE) as GV and a dual-energy X-ray absorptiometry (DEXA) to evaluate skeletal muscle mass were enrolled. Skeletal muscle index (SMI) level was calculated as skeletal muscle mass divided by height squared (kg/m2). SMI level in men had a weak inverse correlation with Log MAGE level by the linear regression model in diabetes mellitus (DM) patients (R2 = 0.139, P = 0.004) and even in non-DM patients (R2 = 0.068, P = 0.004). Multivariate linear regression analysis with a stepwise algorithm (age, male sex, body mass index [BMI], hemoglobin A1c [HbA1c], fasting glucose, HOMA-IR, and SMI; R2 = 0.203, P < 0.001) demonstrated that HbA1c level (B = 0.077, P < 0.001) and SMI level (B = - 0.062, P < 0.001) were both independently associated with Log MAGE level. This association was also confirmed in limited non-DM patients with a subgroup analysis. SMI level was associated with Log MAGE level (B = - 0.055, P = 0.001) independent of BMI or HbA1c level. SMI level was inversely associated with MAGE level independent of glucose metabolism in STEMI patients, suggesting the significance of skeletal muscle mass as blood glucose storage for glucose homeostasis to reduce GV.

Clinical impact of admission urinary 8-hydroxydeoxyguanosine level for predicting cardiovascular mortality in patients with acute coronary syndrome.

The aim of the present study was to determine whether urinary 8-hydroxydeoxyguanosine (8-OHdG), which is a marker of oxidative stress, can predict future cardiovascular death in patients with acute coronary syndrome (ACS). A total of 551 consecutive patients with ACS who underwent admission urinary 8-OHdG measurements were enrolled in this study. The patients were divided into 2 groups according to the optimal cutoff value of admission urinary 8-OHdG determined by a receiver-operating characteristics curve for the prediction of cardiovascular death: a high admission urinary 8-OHdG group, 169 patients with admission urinary 8-OHdG ≥ 17.92 ng/mg creatinine; and a low admission urinary 8-OHdG group, 382 patients with admission urinary 8-OHdG < 17.92 ng/mg creatinine. The patients were followed up for a median period of 34 months. The primary and secondary end points were the incidence of cardiovascular death and major cardiovascular events (MACE) composed of cardiovascular death, non-fatal myocardial infarction, or urgent hospitalization for heart failure. Of the 551 patients, cardiovascular deaths and MACE occurred in 14 (2.5%) and 35 (6.4%), respectively. The Kaplan-Meier estimate of the event-free rate revealed cardiovascular deaths and MACE were more likely in the high admission 8-OHdG group than in the low admission 8-OHdG group (log rank, both P < 0.001). Multiple adjusted Cox proportional hazards analysis indicated that high admission urinary 8-OHdG was an independent predictor of cardiovascular death (hazard ratio [HR] 7.642, P = 0.011) and MACE (HR 2.153, P = 0.049). High admission urinary 8-OHdG levels predict cardiovascular mortality after adjustment in patients with ACS.

Glycemic variability determined with a continuous glucose monitoring system can predict prognosis after acute coronary syndrome.

BACKGROUND: Impaired glucose metabolism is an established risk factor for coronary artery disease. Previous studies revealed that glycemic variability (GV) is also important for glucose metabolism in patients with acute coronary syndrome (ACS). We explored the association between GV and prognosis in patients with ACS. METHODS: A total of 417 patients with ACS who received reperfusion wore a continuous glucose monitoring system (CGMS) in a stable phase after admission and were monitored for at least 24 consecutive h. The mean amplitude of glycemic excursion (MAGE) was calculated as a marker of GV. We divided into two groups based on the highest tertile levels of MAGE (MAGE = 52 mg/dl). The groups were followed up for a median of 39 months [IQR 24-50 months]. The primary endpoint was the incidence of major adverse cardiovascular and cerebrovascular events (MACCE). RESULT: During follow-up, 66 patients experienced MACCE (5 patients had cardiovascular death, 14 had recurrence of ACS, 27 had angina requiring revascularization, 8 had acute decompensated heart failure, and 16 had a stroke). MACCE was more frequently observed in the high MAGE group (23.5% vs. 11.6%, p = 0.002). In multivariate analysis, high MAGE was an independent predictive factor of poor prognosis for MACCE (odds ratio, 1.84; 95% confidence interval, 1.01-3.36; p = 0.045). CONCLUSION: Glycemic variability determined with a CGMS is a predictor of prognosis in patients with ACS without severe DM. Trial registration UMIN 000010620. Registered April 1st 2012.

Non-Covalent Loading of Anti-Cancer Doxorubicin by Modularizable Peptide Self-Assemblies for a Nanoscale Drug Carrier.

We prepared nanoscale, modularizable, self-assembled peptide nanoarchitectures with diameters less of than 20 nm by combining ß-sheet-forming peptides tethering a cell-penetrating peptide or a nuclear localization signal sequence. We also found that doxorubicin (Dox), an anti-cancer drug, was non-covalently accommodated by the assemblies at a ratio of one Dox molecule per ten peptides. The Dox-loaded peptide assemblies facilitated cellular uptake and subsequent nuclear localization in HeLa cells, and induced cell death even at low Dox concentrations. This peptide nanocarrier motif is a promising platform for a biocompatible drug delivery system by altering the targeting head groups of the carrier peptides.

Glycemic Variability on Continuous Glucose Monitoring System Correlates With Non-Culprit Vessel Coronary Plaque Vulnerability in Patients With First-Episode Acute Coronary Syndrome - Optical Coherence Tomography Study.

BACKGROUND: Glycemic variability (GV) is associated with coronary plaque rupture at the culprit lesion in acute myocardial infarction (AMI). The present study determined the relationship between GV and coronary plaque vulnerability in the non-culprit vessel. METHODS AND RESULTS: The present prospective study involved 46 patients with first-episode acute coronary syndrome (ACS) who underwent optical coherence tomography in the non-culprit vessel. The relationship between GV, assessed with continuous glucose monitoring system, and the presence of thin-cap fibroatheroma (TCFA) at the non-culprit plaque with mild-to-moderate stenosis in the non-culprit vessel, was assessed. GV was quantified using mean amplitude of glycemic excursion (MAGE). Patients were divided into tertiles according to MAGE. TCFA was observed in 13 (28%) of the 46 patients. Fibrous cap thickness was thinner (MAGE tertiles: high, 80±40 µm; intermediate, 152±122 µm; low, 155±102 µm; P=0.01), and TCFA was more common (MAGE tertiles: high, 50%; intermediate, 27%; low, 7%; P=0.03) in patients with high MAGE. On multivariate logistic analysis high MAGE was the only significant determinant of TCFA, independent of coronary risk factors (OR, 5.000; P=0.021), homeostasis model assessment of insulin resistance, and hemoglobin A1c(OR, 5.674; P=0.018). CONCLUSIONS: High MAGE measured early after the onset of first-episode ACS correlated with thinner fibrous cap thickness and higher prevalence of TCFA at the non-culprit plaque in the non-culprit vessel.

Association between blood glucose variability and coronary plaque instability in patients with acute coronary syndromes.

BACKGROUND: Blood glucose variability is receiving considerable attention as a new risk factor for coronary artery disease. This study aimed to investigate the association between blood glucose variability and coronary plaque tissue characteristics. METHODS: In 57 patients with acute coronary syndrome, integrated backscatter intravascular ultrasound (IB-IVUS) and gray-scale IVUS were performed before balloon dilatation or stent implantation in the culprit vessels. Standard IVUS indices were evaluated for volume index (volume/length), and plaque components were measured by IB-IVUS for percent tissue volume. In addition to conventional glucose indicators, blood glucose variability in a stable state was determined by calculating the mean amplitude of glycemic excursions (MAGE) using a continuous glucose monitoring system. RESULTS: Higher MAGE values were significantly correlated with larger percent plaque volumes (r = 0.32, p = 0.015), and increased lipid (r = 0.44, p = 0.0006) and decreased fibrous (r = -0.45, p = 0.0005) plaque components. In contrast, HbA1c or fasting plasma glucose values were not significantly correlated with plaque volumes and percent plaque components. Homeostasis model assessment of insulin resistance values were positively correlated with vessel (r = 0.35, p = 0.007) and plaque (r = 0.27, p = 0.046) volumes, but not with percent plaque components. In multiple regression analysis, higher MAGE values were independently associated with increased lipid (ß = 0.80, p = 0.0035) and decreased fibrous (ß = -0.79, p = 0.0034) contents in coronary plaques. CONCLUSIONS: Among all glucose indicators studied, only higher blood glucose variability was an independent determinant of increased lipid and decreased fibrous contents with larger plaque burden, suggesting blood glucose variability as one of the important factors related to coronary plaque vulnerability.

Glycemic Variability on Continuous Glucose Monitoring System Predicts Rapid Progression of Non-Culprit Lesions in Patients With Acute Coronary Syndrome.

BACKGROUND: Although rapid progression (RP) of coronary artery disease (CAD) has been shown to be a powerful predictor of cardiovascular events, predictors of RP are not fully understood in patients with acute coronary syndrome (ACS). METHODS AND RESULTS: We prospectively investigated the clinical impact of glycemic variability (GV), as determined on continuous glucose monitoring system (CGMS), on RP of non-culprit lesions in 88 patients with ACS. RP was defined as ≥10% diameter reduction in a pre-existing stenosis ≥50%; ≥30% diameter reduction in a stenosis <50%; development of a new stenosis ≥30% in a previously normal segment; or progression of any stenosis to total occlusion. Patients were classified into 2 groups according to the presence (progressor, n=20) or absence (non-progressor, n=68) of RP. All patients were equipped with a CGMS during the stable phase, and mean amplitude of glycemic excursion (MAGE) was calculated as a marker of GV. Mean MAGE was significantly higher in progressors than in non-progressors (55±19 mg/dl vs. 37±18 mg/dl, P<0.01). On multiple logistic regression analysis, MAGE was an independent predictor of RP (odds ratio, 1.06 per 1 mg/dl; P<0.01). CONCLUSIONS: MAGE early after the onset of ACS is a predictor of RP of non-culprit lesions.

Glycemic Variability Determined by Continuous Glucose Monitoring System Predicts Left Ventricular Remodeling in Patients With a First ST-Segment Elevation Myocardial Infarction.

BACKGROUND: Impaired glucose metabolism plays an important role in patients with acute myocardial infarction, but the clinical significance of glycemic variability (GV) early after the onset of ST-segment elevation myocardial infarction (STEMI) remains to be fully elucidated. METHODS AND RESULTS: We prospectively investigated the clinical impact of GV, as determined by a continuous glucose monitoring system (CGMS), on left ventricular remodeling (LVR) assessed by cardiac magnetic resonance imaging (CMR) in 69 patients (63±13 years, 59 men) with a first reperfused STEMI within 12 h of onset. All patients were equipped with a CGMS when in a stable phase after admission and underwent repeat CMR at baseline and 7 months follow-up. Patients were divided into 2 groups according to the mean amplitude of glycemic excursions (MAGE). Patients in the upper tertile of MAGE were categorized as group High (H) and the other two-thirds as group Low (L). LVR was defined as an absolute increase in left ventricular end-diastolic volume index of ≥20%. LVR more frequently occurred in group H than in group L (56% vs. 11%, P<0.001). Multivariate analysis showed the higher MAGE group was an independent predictor of LVR in the chronic phase (odds ratio, 13.999; 95% confidence interval, 3.059 to 64.056; P=0.001). CONCLUSIONS: MAGE early after the onset of STEMI identified patients with LVR in the chronic phase.

Roles of aromatic side chains and template effects of the hydrophobic cavity of a self-assembled peptide nanoarchitecture for anisotropic growth of gold nanocrystals.

Gold nanocrystals are promising as catalysts and for use in sensing/imaging systems, photonic/plasmonic devices, electronics, drug delivery systems, and for photothermal therapy due to their unique physical, chemical, and biocompatible properties. The use of various organic templates allows control of the size, shape, structure, surface modification and topology of gold nanocrystals; in particular, currently the synthesis of gold nanorods requires a cytotoxic surfactant to control morphology. To control the shape of gold nanocrystals, we previously demonstrated the de novo design and synthesis of a ß-sheet-forming nonapeptide (RU006: Ac-AIAKAXKIA-NH2, X=L-2-naphthylalanine, Nal) and the fabrication of gold nanocrystals by mixing RU006 and HAuCl4 in water. The reaction afforded ultrathin gold nanoribbons 50-100 nm wide, several nanometers high, and microns long. To understand the mechanism underlying gold nanoribbon formation by the RU006 system, we here report (i) the effects of replacement of the Nal aromatic side chain in the RU006 sequence with other aromatic moieties, (ii) the electrochemical properties of aromatic side chains in the de novo designed template peptides to estimate the redox potential and number of electrons participating in the gold crystallization process, and (iii) the stoichiometry of the RU006 system for gold nanoribbon synthesis. Interestingly, RU006 bearing a naphthalene moiety (oxidation peak potential of 1.50 V vs Ag/Ag(+)) and an analog [Ant(6)]-RU006 bearing a bulky anthracene moiety (oxidation peak potential of 1.05 V vs Ag/Ag(+)) allowed the growth of anisotropic (ribbon-like) and isotropic (round) gold nanocrystals, respectively. This trend in morphology of gold nanocrystals was attributed to spatially-arranged hydrophobic cavities sufficiently large to accommodate the gold precursor and to allow directed crystal growth driven by cross-linking reactions among the naphthalene rings. Support for this mechanism was obtained by decreasing the mole fraction of [Ant(6)]-RU006 against the total concentration of [Ant(6)]-RU006 and [Phe(6)]-RU006: absorption spectra similar to that for RU006 were obtained. Differences in the redox properties of the anthracene and naphthalene moieties scarcely affected morphology. We propose that construction of an appropriate hydrophobic cavity is important for templating gold nanocrystal architectures by peptide self-assembly. This mechanism would be applicable for developing simple, low toxicity, mild synthetic methods for constructing metallic nanomaterials for therapeutic use.

Utility of noninvasive endothelial function test for prediction of deep vein thrombosis after total hip or knee arthroplasty.

BACKGROUND: Venous thromboembolism (VTE) is a common and sometimes lethal postoperative complication of arthroplasty. Endothelial dysfunction is important in the pathogenesis of thrombus formation. Reactive hyperemia-peripheral arterial tonometry (RH-PAT) can noninvasively evaluate endothelial function. This study investigated the predictive value of RH-PAT for deep vein thrombosis (DVT) after lower limb arthroplasty. METHODS AND RESULTS: A prospective observational study of 126 osteoarthritic patients who underwent total knee arthroplasty (TKA) or hip arthroplasty (THA) was conducted. The RH-PAT index (RHI) was measured on the day before surgery, and presence of DVT was checked by ultrasonography or phlebography before and after surgery. Following arthroplasty, DVT was diagnosed in 51 patients (40.5%). RHI in the DVT group (0.58±0.25) was significantly lower than in the non-DVT group (0.71±0.25, P=0.004). RHI was a significant and independent predictor of postoperative DVT in multivariate logistic regression analyses and improved a net reclassification index (23.8%, P=0.022). Subgroup analyses according to operation site with adjustment for Qthrombosis score demonstrated that RHI significantly predicted postoperative DVT in the THA group (odds ratio per 0.1, 0.77; 95% confidence interval 0.60-0.98; P=0.03), but did not reach statistical significance in the TKA group. CONCLUSIONS: Low RHI was significantly associated with DVT after lower limb arthroplasty. Endothelial dysfunction, as assessed by RH-PAT, is potentially useful for identifying patients at high risk for VTE especially after THA.

Successful Catheter Ablation for Paroxysmal Supraventricular Tachycardia with Two Alternating Cycle Lengths.

A 62-year-old male was transferred to our hospital complaining of palpitations. His heart rate was 185/min. Electrocardiogram showed a narrow QRS regular tachycardia and the tachycardia changed spontaneously to another narrow QRS tachycardia with two alternating cycle lengths. The arrhythmia was stopped by the administration of adenosine triphosphate. Findings from electrophysiological study suggested that there was an accessory pathway (AP) and dual atrioventricular (AV) nodal pathways. After AP ablation, any other tachyarrythmias were not induced. We supposed that the tachycardia was paroxysmal supraventricular tachycardia involving AP and anterograde conduction alternating between slow and fast AV nodal pathways.

Autism-like behaviours with transient histone hyperacetylation in mice treated prenatally with valproic acid.

Maternal use of valproic acid (VPA) during pregnancy has been implicated in the aetiology of autism spectrum disorders in children, and rodents prenatally exposed to VPA showed behavioural alterations similar to those observed in humans with autism. However, the exact mechanism for VPA-induced behavioural alterations is not known. To study this point, we examined the effects of prenatal exposure to VPA and valpromide, a VPA analog lacking histone deacetylase inhibition activity, on behaviours, cortical pathology and histone acetylation levels in mice. Mice exposed to VPA at embryonic day 12.5 (E12.5), but not at E9 and E14.5, displayed social interaction deficits, anxiety-like behaviour and memory deficits at age 4-8 wk. In contrast to male mice, the social interaction deficits (a decrease in sniffing behaviour) were not observed in female mice at age 8 wk. The exposure to VPA at E12.5 decreased the number of Nissl-positive cells in the middle and lower layers of the prefrontal cortex and in the lower layers of the somatosensory cortex at age 8 wk. Furthermore, VPA exposure caused a transient increase in acetylated histone levels in the embryonic brain, followed by an increase in apoptotic cell death in the neocortex and a decrease in cell proliferation in the ganglionic eminence. In contrast, prenatal exposure to valpromide at E12.5 did not affect the behavioural, biochemical and histological parameters. Furthermore, these findings suggest that VPA-induced histone hyperacetylation plays a key role in cortical pathology and abnormal autism-like behaviours in mice.

Effect of prenatal valproic acid exposure on cortical morphology in female mice.

We have recently shown that prenatal valproic acid (VPA) exposure causes autism spectrum disorders-like behavioral abnormalities and Nissl-positive cell loss in both prefrontal and somatosensory cortices in male mice. We have also found that VPA-induced social interaction deficits are observed in male but not female offspring. This study demonstrated that the exposure to VPA at embryonic day 12.5 significantly decreased Nissl-positive cell numbers in the prefrontal cortex, but not in the somatosensory cortex, in female offspring. These findings suggest that VPA-induced morphological abnormalities in the somatosensory cortex may be involved in the sex-dependent social interaction deficits.

The costimulatory activity of Tim-3 requires Akt and MAPK signaling and its recruitment to the immune synapse.

Expression of the transmembrane protein Tim-3 is increased on dysregulated T cells undergoing chronic activation, including during chronic infection and in solid tumors. Thus, Tim-3 is generally thought of as an inhibitory protein. We and others previously reported that under some circumstances, Tim-3 exerts paradoxical costimulatory activity in T cells (and other cells), including enhancement of the phosphorylation of ribosomal S6 protein. Here, we examined the upstream signaling pathways that control Tim-3-mediated increases in phosphorylated S6 in T cells. We also defined the localization of Tim-3 relative to the T cell immune synapse and its effects on downstream signaling. Recruitment of Tim-3 to the immune synapse was mediated exclusively by the transmembrane domain, replacement of which impaired the ability of Tim-3 to costimulate T cell receptor (TCR)-dependent S6 phosphorylation. Furthermore, enforced localization of the Tim-3 cytoplasmic domain to the immune synapse in a chimeric antigen receptor still enabled T cell activation. Together, our findings are consistent with a model whereby Tim-3 enhances TCR-proximal signaling under acute conditions.

PIK3IP1/TrIP restricts activation of T cells through inhibition of PI3K/Akt.

Phosphatidylinositol-3 kinases (PI3Ks) modulate cellular growth, proliferation, and survival; dysregulation of the PI3K pathway can lead to autoimmune disease and cancer. PIK3IP1 (or transmembrane inhibitor of PI3K [TrIP]) is a putative transmembrane regulator of PI3K. TrIP contains an extracellular kringle domain and an intracellular domain with homology to the inter-SH2 domain of the PI3K regulatory subunit p85, but the mechanism of TrIP function is poorly understood. We show that both the kringle and p85-like domains are necessary for TrIP inhibition of PI3K and that TrIP is down-modulated from the surface of T cells during T cell activation. In addition, we present evidence that the kringle domain may modulate TrIP function by mediating oligomerization. Using an inducible knockout mouse model, we show that TrIP-deficient T cells exhibit more robust activation and can mediate clearance of Listeria monocytogenes infection faster than WT mice. Thus, TrIP is a negative regulator of T cell activation and may represent a novel target for immune modulation.

Chronic treatment with valproic acid or sodium butyrate attenuates novel object recognition deficits and hippocampal dendritic spine loss in a mouse model of autism.

We recently showed that prenatal exposure to valproic acid (VPA) in mice causes autism-like behavioral abnormalities, including social interaction deficits, anxiety-like behavior and spatial learning disability, in male offspring. In the present study, we examined the effect of prenatal VPA on cognitive function and whether the effect is improved by chronic treatment with VPA and sodium butyrate, histone deacetylase inhibitors. In addition, we examined whether the cognitive dysfunction is associated with hippocampal dendritic morphological changes. Mice given prenatal exposure to VPA exhibited novel object recognition deficits at 9 weeks of age, and that the impairment was blocked by chronic (5-week) treatment with VPA (30 mg/kg/d, i.p.) or sodium butyrate (1.2g/kg/d, i.p.) starting at 4 weeks of age. In agreement with the behavioral findings, the mice prenatally exposed to VPA showed a decrease in dendritic spine density in the hippocampal CA1 region, and the spine loss was attenuated by chronic treatment with sodium butyrate or VPA. Furthermore, acute treatment with sodium butyrate, but not VPA, significantly increased acetylation of histone H3 in the hippocampus at 30 min, suggesting the difference in the mechanism for the effects of chronic VPA and sodium butyrate. These findings suggest that prenatal VPA-induced cognitive dysfunction is associated with changes in hippocampal dendritic spine morphology.