P4384Noninvasive and novel method to evaluate left ventricular contractility using pressure-volume loop area obtained by 3-dimensional speckle tracking echocardiography

Introduction

Left ventricular (LV) pressure-volume (P-V) loop area reflects stroke work (SW), but clinical use of this index is limited by the need of invasive pressure measurement. A noninvasive method to obtain LV pressure-strain loop was recently introduced to assess myocardial work (MW). The minimum LV diastolic pressure (mLVP) was reported to have a strong correlation with Tau and we reported that Tau was noninvasively evaluated by speckle tracking echocardiography (STE).

Purpose

We sought to evaluate the impact of preload change by leg lifts on LV SW noninvasively obtained by the novel method and to examine the utility to assess LV contractility by SW and end-diastolic (ED) volume relation (SW-VED).

Methods

Thirty six controls (age 71±10) and 30 patients with heart failure with reduced ejection fraction (EF) <50% (HF) (age 73±6) were enrolled. LV pressure in a cardiac cycle was estimated using systolic blood pressure (SBP), minimum diastolic pressure (mDP) and ED pressure (EDP) by utilizing the profile of an empiric, normalized reference curve. The mDP and EDP were estimated as (Tau − 33.7)/2.06 and as 12.3 − 10.1 x Log (left atrial active emptying function/minimum volume) as we reported. LVSW was obtained by P-V loop by the combination of these pressures and LV volume using 3-D STE.

Results

LVEF and longitudinal strain in HF before leg up by 3D-STE were lower compared to normal (LVEF; normal: 58±5 vs HF: 39±10*% and strain; −12±3 vs −8±3%*, *p<0.05 vs normal). LVEF was increased after leg up by 7±6% in normal and by 8±8% in HF associated with increased LVED volume (normal: 84±24 to 90±24 and HF: 124±36* to 136±42*ml). LV MW and SW in HF before leg up were lower compared to normal (MW: 1790±412 vs 1002±432*mmHg% and SW: 3946±1682 vs 3352±1026mmHgml). LV SW increased after leg up by 26±19% in normal and by 25±20% in HF. LV SW-VED in normal was greater than HF (241±151 vs 90±54*).

Conclusion

LV SW noninvasively obtained by P-V loop area was increased after leg up in both normal and HF but SW-VED in HF was smaller than normal, indicating reduced contractility in HF. This noninvasive method may be a new echocardiographic approach for quantification of LV SW and contractility.

P3548Noninvasive estimation of left ventricular diastolic function in patients with hypertension and normal ejection fraction using 3-dimensional speckle tracking echocardiography

Background

Left ventricular (LV) relaxation (eTau) and pulmonary capillary wedge pressure (ePCWP) were reported to be estimated by speckle tracking echocardiography (STE). LV camber stiffness (e-c stiffness) may be estimated with the use of 2 diastolic pressure-volume coordinates. The minimum diastolic pressure (mP) is reported to have a strong correlation with Tau.

Purpose

We sought to examine the impact of hypertension on LV diastolic function and LA properties and to elucidate the feature of hypertensive heart failure with preserved EF (HFpEF).

Methods

The e', E/e', Tau, PCWP, LVEDP, LV stiffness, LAV, LA emptying function (LAEF) and LA strain were examined in 53 controls (age 66±11), 136 hypertensive patients (HTN) with normal EF (69±11) and 39 HFpEF (77±14). ePCWP and estimated EDP (eEDP) was calculated as previously reported. Tau was calculated as isovolumic relaxation time/(ln 0.9 x systolic blood pressure − ln PCWP). Myocardial stiffness (e-m stiffness) was estimated as LVED stress/LV strain. LV c-stiffness was calculated as LV pressure change (from mP to EDP) obtained by catheterization divided by LV volume change. Estimated LV c-stiffness (e-c-stiffness) was noninvasively obtained using e-mP and e-EDP. The eTau, eEDP and e-mP by STE were validated by catheterization (n=126).

Results

The mP had a good correlation with Tau (r=0.70, p<0.01). The eTau, eEDP and e-mP by STE had a good correlation with those by catheterization (r=0.75, 0.63 and 0.70, p<0.01). Multivariate analysis revealed that ePCWP and LA strain were independent predictors of HFpEF.

LV diastoric function Variables Control HTN HFpEF LVEF, % 68±6 68±8 63±9*+ LV longitudinal strain x (s–1) 19.1±3.0 16.8±4.3* 14.5±5.1*+ E/e' 9.2±2.6 11.6±4.5* 15.9±7.9*+ eTau, ms 35±12 48±17* 59±17*+ ePCWP, mmHg 7.3±2.7 8.3±4.3 15.0±4.4*+ eLVEDP, mmHg 9.4±2.2 10.4±3.5 15.9±3.7*+ LV e-myocardial stiffness, kdynes/cm 0.56±0.25 0.69±0.56 1.27±0.71*+ LV e-chamber stiffness, mmHg/ml 0.19±0.06 0.20±0.08 0.36±0.19*+ Maximum LAVI, ml/m2 42±15 50±21* 68±17*+ Total LAEF, % 55±7 51±11 36±12*+ LA peak strain 41±15 40±17 19±8*+ *p<0.05 vs Control, +p<0.05 vs HTN.

Conclusion

We demonstrated that LV diastolic function in HTN may be accurately and noninvasively evaluated by STE.

P5593The association of recurrence and bleeding events with mortality after venous thromboembolism: from the COMMAND VTE Registry

Background/Introduction

Venous thromboembolism (VTE), including pulmonary embolism (PE) and deep vein thrombosis (DVT), has a long-term risk for recurrence, which can be prevented by anticoagulation therapy. The duration of anticoagulation therapy after VTE should be based on the balance between risks of recurrent VTE and bleeding. However, there is uncertainty about the impact of these events on subsequent mortality.

Purpose

We sought to evaluate the impact of recurrent VTE events and bleeding events on subsequent mortality in patients with VTE in a large retrospective observational database in Japan.

Methods

We evaluated the association of recurrent VTE and major bleeding with mortality among 3026 patients in the COMMAND VTE Registry. We estimated the risks of recurrent VTE events and major bleeding events for subsequent all-cause death with the multivariable Cox proportional hazard model. We incorporated the recurrent VTE events and major bleeding events during follow-up into the multivariable Cox model as time-updated covariates together with the clinically-relevant 16 risk-adjusting factors. We expressed the adjusted risks of each covariate as hazard ratios (HR) and their 95%confidence intervals (CI). Furthermore, to assess the risks of recurrent PE and recurrent DVT events for subsequent all-cause death respectively, we divided recurrent VTE events into recurrent PE (PE with or without DVT) and recurrent DVT (DVT only), and incorporated these events as well as major bleeding events into the multivariable Cox model as time-updated covariates.

Results

In the current study population, the mean age was 67 years, 61% were women, and mean body weight and body mass index were 57.9 kg and 23.2 kg/m2, respectively. During the median follow-up period of 1,218 days, 763 patients died, 225 patients developed recurrent VTE events, and 274 patients developed major bleeding events. The time-updated multivariable Cox proportional hazard model revealed that both the recurrent VTE events and the major bleeding events were strongly associated with subsequent mortality risk (recurrent VTE events: HR 3.24, 95% CI 2.57–4.08, P<0.001; major bleeding events: HR 3.53, 95% CI 2.88–4.31, P<0.001). Both the recurrent PE events and the recurrent DVT events were associated with subsequent mortality risk with the numerically greater magnitude of effect with the recurrent PE events than with the recurrent DVT events (recurrent PE events: HR 4.42, 95% CI 3.28–5.95, P<0.001; recurrent DVT events: HR 2.42, 95% CI 1.75–3.36, P<0.001).

Conclusions

In the real-world patients with VTE, both recurrent VTE events and major bleeding events were strongly associated with subsequent mortality risk with the comparable effect size. Recurrent PE and recurrent DVT events were also associated with increased risks for mortality, although the magnitude of the effect on mortality was numerically greater with the recurrent PE events than with the recurrent DVT events.

Acknowledgement/Funding

Research Institute for Production Development, Mitsubishi Tanabe Pharma Corporation

P2474Noninvasive estimation of pulmonary capillary wedge pressure by novel 3D speckle tracking echocardiography and validation study by cardiac catheterization

Background

We previously reported that pulmonary capillary wedge pressure (PCWP) was noninvasively evaluated by 2D speckle tracking echocardiography (STE). Recently, novel software was introduced to examine volume and function of left ventricular and left atrium (LA) by 3D-STE automatically.

Purpose

We sought to compare the PCWP estimated by conventional 2D-STE (2D-ePCWP) and by novel 3D-STE (3D-ePCWP), and validate those values by cardiac catheterization.

Methods

Echocardiography and catheterization were performed in 29 patients (age 72±2) (7 ischemic heart disease, 2 hypertensive heart disease, 5 dilated cardiomyopathy, 12 valvular heart disease and 3 primary pulmonary hypertension).The ePCWP (mmHg) is noninvasively obtained as 10.8 − 12.4 x Log (left atrial active emptying function/minimum volume) as we previously reported. Echocardiography was performed just before the catheterization and we analyzed the 2D and 3D data by novel off-line software. 3D data was automatically analyzed and the border settings were fixed at default (ES60, ED30) (Figure).

Results

2D-ePCWP and 3D-ePCWP had a good correlation with PCWP invasively obtained by catheterization (r=0.87 and 0.83, respectively, both p<0.001). There was an excellent correlation between 2D-ePCWP and 3D-ePCWP (r=0.94, p<0.001) and there was a good correlation between 2D-LA volume index and 3D- LA volume index (r=0.80, p<0.001). Bland-Altman analysis revealed a good agreement between 2D-ePCWP and 3D-ePCWP, and between 2D-ePCWP and 3D-ePCWP without fixed and proportional bias.

Conclusion

This study demonstrated that PCWP might be noninvasively assessed by not only 2D-STE but also 3D-STE with reasonable accuracy and 3D-STE might have utility and value in the routine clinical practice.

P4351Validation by cardiac catheterization of noninvasive evaluation of left ventricular chamber and myocardial stiffness as a diastolic function using speckle tracking echocardiography

Background

Left ventricular (LV) diastolic function is mainly composed of LV relaxation and LV stiffness. We reported that pulmonary capillary wedge pressure (ePCWP) and LV relaxation assessed by Tau (eTau) are noninvasively evaluated by speckle tracking echocardiography (STE). The minimum LV diastolic pressure (mLVP) was reported to have a strong correlation with Tau. Therefore, LV chamber stiffness (c-stiffness) may be assessed with the use of two LV diastolic pressure-volume coordinates: the mLVP and volume and the end-diastolic pressure (EDP) and volume.

Purpose

We sought to noninvasively assess LV stiffness using STE and validate the value by cardiac catheterization.

Methods

Echocardiography and catheterization were performed in 124 patients (age 72±8) (70 angina pectoris, 20 prior myocardial infarction, 19 hypertensive heart disease, 11 congestive heart failure and 4 paroxysmal atrial fibrillation). The ePCWP (mmHg) is noninvasively obtained as 10.8 − 12.4 × Log (left atrial active emptying function/minimum volume) and the eTau (ms) is obtained as isovolumic relaxation time/(ln 0.9 × systolic blood pressure − ln ePCWP) as previously reported. The mLVP (e-mLVP) was estimate using Tau. The estimated EDP (e-EDP) was calculated as 12.3 − 10.1 × Log (left atrial active emptying function / minimum volume). LV c-stiffness (mmHg/ml) was calculated as LV pressure change (from mLVP to EDP) obtained by catheterization divided by LV volume change during diastole which equals to stroke volume by echocardiography. Estimated c-stiffness (e-c-stiffness) was noninvasively obtained using e-mLVP and e-EDP. Furthermore, LV myocardial stiffness (m-stiffness) was calculated by LVED stress / LV longitudinal strain by STE, where LV stress (kdynes/cm2) was calculated as 0.334 × pressure × dimension / [thickness (1 + thickness/dimension)]. The estimated m-stiffness (e-m-stiffness) was calculated using e-EDP.

Results

The eTau and e-EDP estimated by STE had a good correlation with Tau and EDP invasively obtained by catheterization (r=0.75 and 0.63, respectively, both p<0.001). There was a good correlation between Tau and mLVP (Tau = 2.06 mLVP + 33.7, r=0.70). The estimated LVED stress had good correlation with ED stress obtained by catheterization (r=0.77, p<0.001). The e-c-stiffness and e-m-stiffness had a good correlation with those obtained by catheterization (e-c-stiffness; 0.116±0.07 and c-stiffness; 0.115±0.06, r=0.603, e-m-stiffness; 0.81±0.41 and m-stiffness; 0.85±0.45, r=0.89, respectively). Bland-Altman analysis revealed a good agreement between e-c-stiffness and c-stiffness, and between e-m-stiffness and m-stiffness without fixed and proportional bias.

Conclusion

This study demonstrated that LV stiffness may be noninvasively assessed by STE with reasonable accuracy and may have utility and value in the routine clinical practice for the diagnosis and treatment in patients with diastolic dysfunction.

P3847Deep vein thrombosis in upper extremities: clinical characteristics, management strategies and long-term outcomes from the COMMAND VTE Registry

Background/Introduction

Pulmonary embolism (PE) is caused by blockage of pulmonary arteries by thrombus. The sources of thrombus are thought to be mostly veins in lower extremities, whereas deep vein thrombosis (DVT) in upper extremities rarely occurs spontaneously. Recent studies reported that DVT in upper extremities might have significant complications, and DVT in upper extremities could be increasing. However, there is a paucity of data on patients with DVT in upper extremities, leading to uncertainty in optimal treatment strategies including anticoagulation therapy.

Purpose

We sought to evaluate the clinical characteristics, management strategies, and long-term outcomes of patients with DVT in upper extremities in a large observational database in Japan.

Methods

The COMMAND VTE Registry is a multicenter registry enrolling 3027 consecutive patients with acute symptomatic venous thromboembolism (VTE) objectively confirmed by imaging examination or by autopsy among 29 centers in Japan between January 2010 and August 2014. The current study population consisted of 2498 patients with DVT in upper or lower extremities, after excluding 381 patients with PE only, 144 patients who had thrombus in locations other than upper or lower extremities, and 4 patients with DVT in both upper and lower extremities. The study patients were divided into 2 groups: patients with DVT in upper extremities and patients with DVT in lower extremities. We compared the clinical characteristics, management strategies and long-term outcomes between the 2 groups.

Results

There were 74 patients (3.0%) with upper extremities DVT and 2498 patients (97%) with lower extremities DVT. Patients with upper extremities DVT more often had active cancer at diagnosis (58%) and central venous catheter use (22%). The proportion of concomitant PE at diagnosis was lower in patients with upper extremities DVT than in those with lower extremities DVT (14% and 51%, P<0.001). Discontinuation of anticoagulation therapy was more frequent in patients with upper extremities DVT (63.8% and 29.8% at 1-year, P<0.001). The cumulative 3-year incidence of recurrent VTE was not different between the 2 groups (9.8% and 7.4%, P=0.43) (Figure). After adjusting confounders, the risks of upper extremities DVT relative to lower extremities DVT for recurrent VTE remained insignificant (HR 0.94, 95% CI 0.36–2.01, P=0.89).

Kaplan-Meier event curves for recurrence

Conclusions

The prevalence of patients with DVT in upper extremities was 3.0% in the current large-scale real-world registry. Patients with DVT in upper extremities more often had active cancer at diagnosis and central venous catheter use as a transient risk factor for VTE, and less often had concomitant PE. Patients with DVT in upper extremities had similar long-term risk for recurrent VTE as those with DVT in lower extremities despite shorter duration of anticoagulation.

Acknowledgement/Funding

Research Institute for Production Development, Mitsubishi Tanabe Pharma Corporation

SIRT7 regulates the nuclear export of NF-κB p65 by deacetylating Ran

Sirtuin 7 (SIRT7) is an NAD+-dependent lysine deacetylase that regulates diverse biological processes. We recently observed that SIRT7 deficiency suppresses the nuclear accumulation of p65, which is a component of nuclear factor kappa B. However, the underlying molecular mechanism remains elusive. In this study, we demonstrated that SIRT7 interacts with a small GTPase, Ras-related nuclear antigen (Ran), and deacetylates Ran at K37. The nuclear export of p65 was facilitated in SIRT7-deficient fibroblast cells, while the nuclear export was inhibited in SIRT7-deficient cells expressing K37R-Ran (deacetylation-mimicking mutant). Additionally, the nuclear export of p65 in wild-type fibroblast cells was promoted by K37Q-Ran (acetylation-mimicking mutant). K37Q-Ran exhibited an increased ability to bind to chromosome region maintenance 1 (CRM1), which is a major nuclear receptor that mediates the export of cargo proteins, and enhanced the binding between p65 and CRM1. These data suggest that SIRT7 is a lysine deacetylase that targets the K37 residue of Ran to suppress the nuclear export of p65.

A-41 Verbal Fluency and Switching Accuracy Differences in Pediatric Epilepsy Pre- and Post- Surgery

Objective

In patients with epilepsy, research is variable with regard to language difficulties. Previous research generally focuses on phonemic and semantic verbal fluency in pediatric populations post-surgery; however, few studies examine category switching accuracy. This study compared phonemic fluency, categorical fluency, switching accuracy, and the number of switches among pre-surgical and post-surgical groups.

Methods

Participants included 31 epilepsy patients (age 5-20 years old; M = 12.23 years pre-surgery; M = 14.72 years post-surgery; 20 males, 11 females) who underwent neuropsychological evaluations prior to and following open brain resection surgery (i.e., temporal lobectomy, temporal resection, frontal lobectomy). Verbal Fluency was assessed by the Delis-Kaplan Executive Functioning System (D-KEFS), measuring phonemic fluency, categorical fluency, switching accuracy, and the number of switches.

Results

Statistically significant differences were found between groups on the D-KEFS Verbal Fluency subtest using a one-way ANOVA. Specifically, switching accuracy decreased following surgery, F(1,25) = 6.470, p = 0.02 (M = 104.44 pre-surgery, M = 89.44 post-surgery). Further, a downward trend was noted regarding the number of switches between the two groups, F (1, 26) = 3.172, p = 0.09; however, no differences were found in phonemic, F(1,34) = 0.854, p = 0.63, and categorical, F(1,35) = 0.828, p = 0.37, fluency tasks.

Conclusions

Results from this study revealed a decrease in the participants ability to accurately switch between verbal categories following brain resection surgery. Similarly, a downward trend was noted for number of switches completed pre- and post- surgery. Consistent with previous research, phonemic and semantic verbal fluency tasks remain unchanged post-surgery. Implications of this study highlight the need to assess executive functioning after surgery as it has an impact on treatment outcome and school planning.

A-36 Cognitive Differences Between Children with New Onset Seizures and Those with Longer Seizure Histories

Objective

Epilepsy is associated with cognitive difficulties including language and memory problems. Studies examining cognitive function in children with new onset seizures have found that they have difficulties when compared to healthy controls, but less is known about how these difficulties compare to cognitive function in children who have had seizures for longer periods. Our study compared semantic memory and verbal fluency skills in a group of pediatric patients with new onset seizures (< 12 months) to a group of presurgical epilepsy patents who had seizures for more than 12 months.

Method

Participants included 12 new onset seizure patients (age 8–15 years old; M = 12.13 years, SD = 2.4; 58.3% male), and 14 presurgical epilepsy patients (age 8-18 years old; M = 13.26 years, SD = 3.3; 64.3% male) who underwent neuropsychological evaluations as part of their standard of care. All patients were recruited from a regional children’s hospital. Outcome variables included performance on the Boston Naming Test (BNT) and Delis-Kaplan Executive Function System Verbal Fluency test, Letter (LF) and Category (CF) Fluencies.

Results

Overall intellectual ability did not differ significantly between groups. No significant differences were found between the two groups on the BNT [F (17,2) = 1.012, p = .607], LF [F (8,16) = 1.375, p = .279], or CF [F (7,17) = .544, p = .790].

Conclusions

Findings indicating no significant differences on cognitive tasks between the two groups are consistent with previous research indicating that individuals with new onset seizures often exhibit cognitive difficulties at the time their seizures begin.

A-68 Yoga Therapy in Pediatric Epilepsy

Objective

This pilot study examines the effects of yoga therapy on anxiety, depression symptoms, inattention, and seizure frequency in children diagnosed with Epilepsy.

Data Selection

The sample consisted of 5 participants (4 male, 1 female), ages 7-12 years old, with diagnoses of generalized epilepsy, absence epilepsy, and complex partial epilepsy. Participants all had average cognitive abilities (IQ SS = 100.7; VCI SS = 106.3; PRI SS = 108.3), a diagnosis of Attention Deficit Hyperactivity Disorder (ADHD), and clinically significant levels of anxiety and depression. Participants participated in 30-45-minute-long yoga sessions over a 6-week period with 2-3 home sessions each week. Differences in hyperactivity, anxiety, depression, and inattention were measured via parent rating Likert scales (0-poor, 10-best) at 1 month, 3 months, and 6 months. Participants also completed weekly self-report measures to assess anxiety and depression (Revised Children’s Manifest Anxiety, Second Edition (RCMAS-2) and Children’s Depression Inventory, Second Edition (CDI-2)).

Data Synthesis

No significant reliable change differences were found between sessions; however, a downward trend was visible in reduction of anxiety (RCMAS-2; first session M = 16.4, last session M = 9.4) and depression symptoms (CDI-2; first session M = 52.8, last session M = 49.2). Further, parents reported a decrease in anxiety (first session M = 4.8, last session M = 6.4). No seizures were reported during the study.

Conclusions

There is no previous research using pediatric populations and yoga therapy effects on reducing seizure frequency, anxiety, depression, and attention problems. This pilot study showed promising results in reducing anxiety, and depression symptoms. Limitations of study include small sample size and attrition, which are both important to consider when conducting another study.

A-38 Examining Cognitive Differences of Pre- and Post- Surgery in Pediatric Epilepsy

Objective

Intractable epilepsy is often associated with cognitive difficulties in the language domain. Few studies examining verbal domains of cognitive functioning indicate a small increase of verbal skills post-surgery. The current study compared Verbal IQ and Performance IQ domains in pediatric populations before and after open resection surgery.

Method

Participants included 31 epilepsy patients (age 5-20 years old; M = 12.23 years pre-surgery; M = 14.72 years post-surgery; 20 males, 11 females) who underwent neuropsychological evaluations prior to and following an open brain resection surgery (i.e., temporal lobectomy, temporal resection, frontal lobectomy). Cognitive ability was assessed by Weschler Abbreviated Scale of Intelligence (WASI) in order to analyze differences between pre-surgical and post-surgical cognitive function, specifically verbal comprehension and perceptual reasoning ability.

Results

No statistically significant differences were found, using a One-way ANOVA, between the two groups; however, a downward trend was noted for the Verbal IQ (VIQ) domain, F(1, 25) = 2.624, p = 0.118, including the verbal subtests vocabulary, F(1, 23) = 2.203, p = 0.151, and similarities, F(1, 24) = 1.678, p = 0.207. No differences or trends were noted within the Performance IQ (PIQ) domain, block design, or matrix reasoning.

Conclusions

Findings indicated that participants verbal ability decreased after epilepsy surgery when compared to prior evaluations. This is not consistent with previous research, which stated an increase in verbal abilities following surgical resection. Variable time between surgery and re-evaluation might account for discrepancies. Further, no differences in nonverbal reasoning abilities were noted. Results indicated a need for further research in open brain resection surgeries and the outcome of verbal processing.

Current-feedback-stabilized laser system for quantum simulation experiments using Yb clock transition at 578 nm

We developed a laser system for the spectroscopy of the clock transition in ytterbium (Yb) atoms at 578 nm based on an interference-filter stabilized external-cavity diode laser (IFDL) emitting at 1156 nm. Owing to the improved frequency-to-current response of the laser-diode chip and the less sensitivity of the IFDL to mechanical perturbations, we succeeded in stabilizing the frequency to a high-finesse ultra-low-expansion glass cavity with a simple current feedback system. Using this laser system, we performed high-resolution clock spectroscopy of Yb and found that the linewidth of the stabilized laser was less than 320 Hz.

The significance of lipid accumulation in breast carcinoma cells through perilipin 2 and its clinicopathological significance

Both systemic and intratumoral lipid metabolism have been recently reported to play pivotal roles in both tumor development and progression in various human malignancies including breast cancer. However, its details have remained largely unknown in breast cancer patients. Therefore, in this study, we focused on perilipin 2, which is involved in constituting the intracellular lipid composition. Perilipin 2 was first immunolocalized in 105 cases of breast cancer. The status of perilipin 2 immunoreactivity was significantly positively associated with histological grade, Ki-67 labeling index and HER2 status and negatively with estrogen receptor status of these patients. Subsequent in vitro study also revealed that its mRNA expression in triple negative breast carcinoma cells was higher than cells of other subtypes. We then examined the correlation between perilipin 2 immunoreactivity and intracellular lipid droplet evaluated by Oil-red O stating in 13 cases of breast carcinoma tissues. A significantly positive correlation was detected between the status of perilipin 2 and Oil-red O staining. These findings above did indicate that perilipin 2 could represent the status of intracellular lipid droplets in surgical pathology specimens of breast cancer and perilipin 2 was also associated with its more aggressive biological phenotypes.

Quantum Interferometry with a g-Factor-Tunable Spin Qubit

We study quantum interference effects of a qubit whose energy levels are continuously modulated. The qubit is formed by an impurity electron spin in a silicon tunneling field-effect transistor, and it is read out by spin blockade in a double-dot configuration. The qubit energy levels are modulated via its gate-voltage-dependent g factors, with either rectangular, sinusoidal, or ramp radio frequency waves. The energy-modulated qubit is probed by the electron spin resonance. Our results demonstrate the potential of spin qubit interferometry implemented in a silicon device and operated at a relatively high temperature.

Difluoroboron Chelation to Quinacridonequinone: A Synthetic Method for Air-Sensitive 6,13-Dihydroxyquinacridone via Boron Complexes

This study aims to perform the chelation of difluoroboron (BF₂ ) to quinacridonequinone (QQ). The resulting dark green solid was determined to be QA-BF₂ , which is a BF₂ complex of 6,13-dihydroxyquinacridone (QA-OH), and not QQ-BF₂ , which is a BF₂ complex of QQ. This result indicated that QQ-BF₂ was first generated as an O,O-bidentate chelate, which immediately underwent a two-electron reduction to produce QA-BF₂ . This compound was converted to air-sensitive QA-OH by undergoing hydrolysis in argon. Since QA-OH has a strong electron-donating property, it easily produced QQ via air oxidation in the solution. QA-OH also acts as a reducing reagent for quinones. The crystal packing of QA-OH is a herringbone type with short π⋅⋅⋅π contacts, and a good hole mobility has been suggested by theoretical calculations. Herein, a new synthetic method from QQ to QA-OH using BF₂ chelation and hydrolysis was proposed. QA-BF₂ and QA-OH are useful organic functional pigments and reducing reagents.