Lung fluid levels estimated by remote dielectric sensingTM values and invasive hemodynamic measurements

Background

Remote dielectric sensing (ReDSTM) is a recently introduced non-invasive electromagnetic-based technology to quantify lung fluid levels (Figure 1A). The association between ReDS values and invasively measured hemodynamics, particularly among those with small body size, remains uncertain.

Methods

Consecutive patients with chronic heart failure who were admitted to our institute and underwent right heart catheterization as well as simultaneous ReDS measurement at clinically stable conditions between Sep and Nov 2021 were prospectively included. The correlation between ReDS values and PCWP was investigated.

Results

A total of 30 patients (median 79 [73, 84] years old, 13 men) were included. Median ReDS value was 26% (22%, 28%). ReDS values had a moderate correlation with PCWP (r=0.698, p<0.001; Figure 1B), even among those with a height <155 cm. ReDS values with a cutoff 28% predicted a PCWP >15 mmHg with sensitivity 0.70 and specificity 0.75.

Conclusions

A non-invasive electromagnetic-based technology ReDS might be a promising tool to estimate cardiac pressure in patients with heart failure, even among those with smaller body size.

Funding Acknowledgement

Type of funding sources: None.

The effect of achieving LDL-C <1.8 mmol/L to prevent the first atherosclerotic cardiovascular events in the primary prevention settings of severe heterozygous familial hypercholesterolemia

Introduction

The International Atherosclerosis Society (IAS) has proposed “severe familial hypercholesterolemia” (FH) as a phenotype with the highest cardiovascular risk. LDL-C <2.5 mmol/l is a recommended therapeutic goal for the primary prevention settings of severe FH. However, given that ESC guidelines recommends LDL-C <1.8 mmol/l in FH patients, this stricter goal may be better to prevent the first atherosclerotic cardiovascular disease (ASCVD) in severe FH patients.

Purpose

To determine whether achieving LDL-C<1.8 mg/dl is more beneficial to reduce the first ASCVD events.

Methods

A total of 148 severe FH subjects without any history of ASCVD were analyzed. Severe FH was defined as untreated LDL-C >10.3 mmol/l, LDL-C >8.0 mmol/l+ 1 high-risk feature, LDL-C >4.9 mmol/l + 2 high-risk features according to IAS proposed statement. The occurrence of ASCVD (all-cause death, CAD, ischemic stroke and lower extremity artery disease (LEAD)) were compared in those with on-treatment LDL-C < and ≥1.8 mmol/L.

Results

10.1% (=15/148) of study subjects achieved on-treatment LDL-C <1.8 mmol/l. They were more likely to receive PCSK9 inhibitor (15.0 vs. 66.7%, p<0.01), whereas there was no significant difference in FH-related physical characteristics (tendon xanthomas: 72.2 vs. 93.3%, p=0.12) and causative genotypes (LDLR: 68.4 vs. 66.7%, p=1.00, PCSK9: 8.3 vs. 6.7%, p=1.00, LDLR/PCSK9: 3.8 vs. 6.7%, p=0.48), untreated LDL-C (7.3±1.7 vs. 7.9±1.8 mmol/l, p=0.22) and lipoprotein(a) (23 [11–42] vs. 25 [15–70] mg/dl, p=0.41) levels between two groups. During the observational period (median=7.0 years), severe FH achieving on-treatment LDL-C <1.8 mmol/l was associated with a lower likelihood of experiencing ASCVD events (Figure 1). Of note, any cardiovascular events did not occur in severe FH who achieved on-treatment LDL-C <1.8 mmol/l. In those with on-treatment LDL ≥1.8 mmol/L, CAD (76.5%=26/34) was more dominant component of ASCVD, followed by ischemic stroke (17.6%=6/34) and LEAD (5.9%=2/34).

Conclusions

A significantly lower frequency of ASCVD was observed in severe FH who achieved LDL-C <1.8 mmol/L in the primary prevention settings. Given that only 10.1% of severe FH patients achieved LDL-C <1.8 mmol/l, more actions are required to motivate physicians for further intensified management of LDL-C in severe FH patients in the primary prevention settings.

Funding Acknowledgement

Type of funding sources: None.

Reaction Mechanism and Selectivity Control of Si Compound ALE Based on Plasma Modification and F-Radical Exposure

In this work, atomic layer etching (ALE) of Si compounds using H₂ or N₂ plasma modification followed by fluorine radical exposure is discussed. It is shown that the H₂ plasma modification process promotes the selective etching of SiN, SiC, and SiCO versus SiO₂. The N₂ plasma modification, on the other hand, enables the selective etching of SiC and SiCO versus SiN and SiO₂. The origin of the etching selectivity between different Si compounds is investigated using a combination of in situ SE and FTIR supported by several ex situ analysis techniques. It is shown that the formation of a hydrogen-rich layer after plasma modification is essential to enable the ALE process. The hydrogen-rich layer can be formed due to ion and radicals of the modification plasma (H₂ plasma modification) or be a result of the reconfiguration of hydrogen that is already present in the film (N₂ plasma modification). The obtained insights are expected to further enhance the etching selectivity of Si compound ALE processes. Furthermore, it is anticipated that the process can be extended to many other compound materials such as Ti and Hf, as well as enable selective etching between their oxides, carbides, and nitrides.

Achilles tendon thickness assessed by X-ray predicting a pathogenic mutation in familial hypercholesterolemia gene

Background

The 2017 Japan Atherosclerosis Society (JAS) familial hypercholesterolemia (FH) criteria adopts a cut off value of ≥9 mm of Achilles tendon thickness (ATT) detected by X-ray as one of the three key items. This threshold was determined based on an old data assessing ATT of 36 non-FH individuals published in 1977. Although the specificity of this clinical criteria is extremely high due to a strict threshold, there are substantial number of patients with FH whose ATT <9 mm. We aimed to determine a cut off value of ATT detected by X-ray to differentiate FH and non-FH based on genetic diagnosis.

Methods

The individuals (male/female = 486/501) with full assessments of genetic analyses for FH-genes (LDLR, and PCSK9), serum lipids, and ATT detected by X-ray at Kanazawa University Hospital and National Cerebral and Cardiovascular Center Research Institute were included in this study. Receiver operating characteristic (ROC) analyses were performed to determine a better cut off point of ATT predicting a pathogenic mutation of FH.

Results

ROC analyses revealed the best cut off values of ATT as 7.6 mm for male, and 7.0 mm for female with the sensitivities and specificities of 0.83 and 0.83 for male and 0.86 and 0.85 for female, respectively. If the thresholds of ATT of 8.0/7.5 mm and 7.5/7.0 mm were applied to diagnose of male/female FH, the sensitivities/specificities predicting a pathogenic mutation of FH by the 2017 JAS FH clinical criteria would be 0.82/0.90 and 0.85/0.88, respectively.

Conclusions

These results suggest that the cut-off value of ATT detected by X-ray is obviously lower than 9.0 mm adopted by the 2017 JAS FH clinical criteria.

Funding Acknowledgement

Type of funding sources: None.

Laser Spectroscopy Measurements of Metastable Pionic Helium Atoms at Paul Scherrer Institute

We review recent experiments carried out by the PiHe collaboration of the Paul Scherrer Institute (PSI) that observed an infrared transition of three-body pionic helium atoms by laser spectroscopy. These measurements may lead to a precise determination of the charged pion mass, and complement experiments of antiprotonic helium atoms carried out at the new ELENA facility of CERN.

Lp (a) >50 mg/dl predicts atherosclerotic cardiovascular events in patients with heterozygous familial hypercholesterolemia who achieved LDL-C <2.6 mmol/l

Introduction

Lipoprotein (a) [Lp (a)] is a plasma lipoprotein which exhibits atherogenic properties. Lp(a) ≥50 mg/dl has been recently shown to associate with a risk of atherosclerotic cardiovascular diseases (ASCVD) in patients with heterozygous familial hypercholesterolemia (HeFH). While current guideline recommends lowering LDL-C as a first-line therapeutic approach in HeFH subjects, it remains to be fully determined whether an elevated level of Lp(a) confers additional ASCVD risks in HeFH patients who achieved a lower LDL-C level.

Purpose

To investigate cardiovascular outcomes in HeFH subjects with a lower LDL-C but an elevated Lp(a) levels.

Methods

182 HeFH patients with on-treatment LDL-C <2.6 mmol/l under lipid-lowering therapies were analyzed. Clinical characteristics and MACE (= a composite of all-cause death, ACS, stroke, PAD and coronary revascularization) were compared in HeFH subjects with Lp(a) ≥ vs. <50 mg/dl.

Results

The averaged LDL-C and Lp (a) levels were 1.9 mmol/l and 26.8 mg/dl, respectively. 19.2% of study subjects exhibited Lp(a)≥50 mg/dl. HeFH patients with Lp(a) ≥50 mg/dl were more likely to be older and have a history of hypertension, but these comparisons did not meet statistical significance. There was no significant difference in on-treatment LDL-C, HDL-C and Triglyceride level (Table). However, during the observational period (median=4.7 years), there was a 2.7-fold (95% CI, 1.41–5.02; p=0.004) greater likelihood of experiencing MACE in subjects with Lp(a) ≥50 mg/dl (picture). Even after adjusting clinical demographics, Lp(a) ≥50 mg/dl remained an independent predictor for the occurrence of MACE (hazard ratio=2.53, 95% CI: 1.29–4.82, p<0.001).

Conclusions

Despite achieving on-treatment LDL-C <2.6 mmol/l, an elevated risk of MACE was observed in HeFH patients with Lp(a) ≥50 mg/dl. Our findings suggest an increased level of Lp(a) as a risk stratification marker and a potential therapeutic target in patients with HeFH.

Clinical outcome

Funding Acknowledgement

Type of funding source: None

Prevalence, clinical characteristics and prognosis of intracranial artery atherosclerosis in heterozygous familial hypercholesterolemia: insights from magnetic resonance angiography imaging analysis

Introduction

Heterozygous familial hypercholesterolemia (HeFH) exhibits substantially atherogenic substrate which involves coronary and peripheral arteries. Whether atherosclerosis in HeFH propagates to intracranial arteries causing stroke remains to be determined.

Purpose

To characterize intracranial artery stenosis (IAS) in subjects with HeFH.

Methods

148 HeFH subjects who underwent MRI/MRA imaging to evaluate intracranial arteries were analyzed. IAS was defined as the presence of stenosis with its % diameter stenosis ≥25%. Clinical demographics and cardiovascular events (all-cause death, ACS, stroke and PAD) were compared in those with and without IAS.

Results

IAS was observed in 24.3% (=36/148) of study subjects. It was more frequently located at middle cerebral artery (30.6%=11/36), followed by internal carotid artery (25.0%=9/36). 47.2% of IAS exhibited % diameter stenosis ≥75%. Furthermore, 58.3% of HeFH patients with IAS exhibited concomitance of CAD, PAD or carotid stenosis. They were more likely to be older (Table). While there was no significant difference in LDL-C level, an elevated triglyceride level was observed in those with IAS (Table). Of note, during the observational period (median=14.1 years), IAS was associated with a greater likelihood of experiencing not only stroke but other cardiovascular events (all-cause death + ACS + PAD) (picture). Multivariate analysis demonstrated triglyceride level ≥1.7mmol/l as an independent predictor of IAS in HeFH patients (HR=5.53, 95% CI: 1.85–16.5, p=0.002).

Conclusions

Around one-fourth of HeFH patients harboured IAS, which was associated with concomitance of atherosclerosis in other vascular beds and the occurrence of stroke and other cardiovascular events. Given the relationship of IAS with hypertriglyceridemia, this lipid feature may be an important contributor to atherosclerotic formation which involves intracranial artery in HeFH patients.

Clinical outcome

Funding Acknowledgement

Type of funding source: None

Myelin and Axonal Damage in Normal-Appearing White Matter in Patients with Moyamoya Disease

BACKGROUND AND PURPOSE

Although chronic ischemia is known to induce myelin and axonal damage in animal models, knowledge regarding patients with Moyamoya disease is limited. We aimed to investigate the presence of myelin and axonal damage in Moyamoya disease and their relationship with cognitive performance.

MATERIALS AND METHODS

Eighteen patients with Moyamoya disease (16-55 years of age) and 18 age- and sex-matched healthy controls were evaluated with myelin-sensitive MR imaging based on magnetization transfer saturation imaging and 2-shell diffusion MR imaging. The myelin volume fraction, which reflects the amount of myelin sheath; the g-ratio, which represents the ratio of the inner (axon) to the outer (axon plus myelin) diameter of the fiber; and the axon volume fraction, which reflects axonal components, were calculated and compared between the patients and controls. In the patients with Moyamoya disease, the relationship between these parameters and cognitive task-measuring performance speed was also evaluated.

RESULTS

Compared with the healthy controls, the patients with Moyamoya disease showed a significant decrease in the myelin and axon volume fractions (P < .05) in many WM regions, while the increases in the g-ratio values were not statistically significant. Correlations with cognitive performance were most frequently observed with the axon volume fraction (r = 0.52-0.54; P < .03 in the right middle and posterior cerebral artery areas) and were the strongest with the g-ratio values in the right posterior cerebral artery region (r = 0.64; P = .004).

CONCLUSIONS

Myelin-sensitive MR imaging and diffusion MR imaging revealed that myelin and axonal damage exist in patients with Moyamoya disease. The relationship with cognitive performance might be stronger with axonal damage than with myelin damage.

148 Inappropriate elevation of angiopoietin-2 relative to hemodynamic stability is associated with bleeding events in patients with continuous flow mechanical circulatory support

Funding Acknowledgements

none

Background

Elevated angiopoietin-2 (Ang-2) has been attributable to a potential cause of gastrointestinal bleeding among patients with continuous flow (CF) mechanical circulatory support (MCS) in the US, but Ang-2 levels have not been examined in the Japanese MCS patients who are likely to have less gastrointestinal bleeding.

Methods

We enrolled 18 patients (64 ± 16y; LVEF 26 ± 9%) with advanced heart failure (HF) who received temporary or durable MCS, or were given intravenous inotropes from August 2018 to January 2019. Serum Ang-2 and plasma BNP were simultaneously measured at various treatment status. The relationship between each value and any spontaneous bleeding events requiring hemostasis or blood transfusion was examined.

Results

103 blood samples were collected and divided into 2 groups. One was the CF group, which consisted of samples from patients under CF-MCS (Impella, ECMO, Jarvik2000, HeartMateII), and the others were assigned to the Non-CF group. Ang-2 levels had a positive correlation with BNP levels (r = 0.33, p = 0.0006, Fig). CF-MCS efficiently lowered BNP levels (353 ± 125 in CF vs 1053 ± 119 in Non-CF, pg/mL, p &lt; 0.0001), but Ang-2 levels relative to BNP levels were significantly higher in the CF group as shown in the Figure (Ang-2/log10(BNP) ratio: 3.77 ± 0.30 in CF vs 2.43 ± 0.29 in Non-CF, p = 0.0017). Bleeding events were remarkably frequent when Ang-2/log10(BNP)&gt;3.17 (77.8%) than ≦3.17 (22.2%, p = 0.0002).

Conclusions

High Ang-2 level is normally a marker for hemodynamic compromise, but CF-MCS may stimulate Ang-2 production despite hemodynamic stabilization. Most of spontaneous bleeding events accompany inappropriately high Ang-2 relative to BNP level among Japanese patients with advanced HF.

Abstract 148 Figure. Correlation between Ang-2 and BNP

Bayesian Estimation of CBF Measured by DSC-MRI in Patients with Moyamoya Disease: Comparison with 15O-Gas PET and Singular Value Decomposition

BACKGROUND AND PURPOSE

CBF analysis of DSC perfusion using the singular value decomposition algorithm is not accurate in patients with Moyamoya disease. This study compared the Bayesian estimation of CBF against the criterion standard PET and singular value decomposition methods in patients with Moyamoya disease.

MATERIALS AND METHODS

Nineteen patients with Moyamoya disease (10 women; 22-52 years of age) were evaluated with both DSC and ¹⁵O-gas PET within 60 days. DSC-CBF maps were created using Bayesian analysis and 3 singular value decomposition analyses (standard singular value decomposition, a block-circulant deconvolution method with a fixed noise cutoff, and a block-circulant deconvolution method that adopts an occillating noise cutoff for each voxel according to the strength of noise). Qualitative and quantitative analyses of the Bayesian-CBF and singular value decomposition-CBF methods were performed against ¹⁵O-gas PET and compared with each other.

RESULTS

In qualitative assessments of DSC-CBF maps, Bayesian-CBF maps showed better visualization of decreased CBF on PET (sensitivity = 62.5%, specificity = 100%, positive predictive value = 100%, negative predictive value = 78.6%) than a block-circulant deconvolution method with a fixed noise cutoff and a block-circulant deconvolution method that adopts an oscillating noise cutoff for each voxel according to the strength of noise (P < .03 for all except for specificity). Quantitative analysis of CBF showed that the correlation between Bayesian-CBF and PET-CBF values (ρ = 0.46, P < .001) was similar among the 3 singular value decomposition methods, and Bayesian analysis overestimated true CBF (mean difference, 47.28 mL/min/100 g). However, the correlation between CBF values normalized to the cerebellum was better in Bayesian analysis (ρ = 0.56, P < .001) than in the 3 singular value decomposition methods (P < .02).

CONCLUSIONS

Compared with previously reported singular value decomposition algorithms, Bayesian analysis of DSC perfusion enabled better qualitative and quantitative assessments of CBF in patients with Moyamoya disease.

P938Extensive formation of atherosclerotic cardiovascular disease in subjects with severe familial hypercholesterolemia defined by the international atherosclerosis society criteria

Introduction

The International Atherosclerosis Society (IAS) has proposed “severe familial hypercholesterolemia (FH)” as a FH phenotype with the highest cardiovascular risk. Coronary artery disease (CAD) represents a major atherosclerotic change in FH patients. Given their higher LDL-C level and atherogenic clinical features, more extensive formation of atherosclerosis cardiovascular disease including not only CAD but stroke/peripheral artery disease (PAD) may more frequently occur in severe FH.

Methods

481 clinically-diagnosed heterozygous FH subjects were analyzed. Severe FH was defined as untreated LDL-C>10.3 mmol/l, LDL-C>8.0 mmol/l+ 1 high-risk feature, LDL-C>4.9 mmol/l + 2 high-risk features or presence of clinical ASCVD according to IAS proposed statement. Cardiac (cardiac death and ACS) and non-cardiac (stroke and peripheral artery disease) events were compared in severe and non-severe FH subjects.

Results

Severe FH was identified in 50.1% of study subjects. They exhibit increased levels of LDL-C and Lipoprotein (a) with a higher frequency of LDLR mutation. Furthermore, a proportion of %LDL-C reduction>50% was greater in severe FH under more lipid-lowering therapy (Table). However, during the observational period (median=6.3 years), severe FH was associated with a 5.9-fold (95% CI, 2.05–25.2; p=0.004) and 5.8-fold (95% CI, 2.02–24.7; p=0.004) greater likelihood of experiencing cardiac-death/ACS and stroke/PAD, respectively (picture). Multivariate analysis demonstrated severe FH as an independent predictor of both cardiac-death/ACS (hazard ratio=3.39, 95% CI=1.12–14.7, p=0.02) and stroke/PAD (hazard ratio=3.38, 95% CI=1.16–14.3, p=0.02) events.

Clinical characteristics of severe FH Non-severe FH Severe FH P-value Baseline LDL-C (mmol/l) 5.3±1.5 6.6±2.0 <0.0001 Lp(a) (mg/dl) 15 [8–28] 21 [10–49] <0.0001 LDLR mutation (%) 49.6% 58.9% 0.00398 On-treatment LDL-C (mmol) 133 [106–165] 135 [103–169] 0.9856 %LDL-C reduction>50% 21.3% 49.8% <0.0001 High-intensity statin (%) 13.3% 42.3% <0.0001 PCSK9 inhibitor (%) 6.3% 21.2% <0.0001

Clinical outcome

Conclusions

Severe FH subjects exhibit substantial atherosclerotic risks for coronary, carotid and peripheral arteries despite lipid lowering therapy. Our finding underscore the screening of systemic arteries and the adoption of further stringent lipid management in severe FH patients.

White Matter Abnormalities in Multiple Sclerosis Evaluated by Quantitative Synthetic MRI, Diffusion Tensor Imaging, and Neurite Orientation Dispersion and Density Imaging

BACKGROUND AND PURPOSE

A number of MR-derived quantitative metrics have been suggested to assess the pathophysiology of MS, but the reports about combined analyses of these metrics are scarce. Our aim was to assess the spatial distribution of parameters for white matter myelin and axon integrity in patients with relapsing-remitting MS by multiparametric MR imaging.

MATERIALS AND METHODS

Twenty-four patients with relapsing-remitting MS and 24 age- and sex-matched controls were prospectively scanned by quantitative synthetic and 2-shell diffusion MR imaging. Synthetic MR imaging data were used to retrieve relaxometry parameters (R1 and R2 relaxation rates and proton density) and myelin volume fraction. Diffusion tensor metrics (fractional anisotropy and mean, axial, and radial diffusivity) and neurite orientation and dispersion index metrics (intracellular volume fraction, isotropic volume fraction, and orientation dispersion index) were retrieved from diffusion MR imaging data. These data were analyzed using Tract-Based Spatial Statistics.

RESULTS

Patients with MS showed significantly lower fractional anisotropy and myelin volume fraction and higher isotropic volume fraction in widespread white matter areas. Areas with different isotropic volume fractions were included within areas with lower fractional anisotropy. Myelin volume fraction showed no significant difference in some areas with significantly decreased fractional anisotropy in MS, including in the genu of the corpus callosum and bilateral anterior corona radiata, whereas myelin volume fraction was significantly decreased in some areas where fractional anisotropy showed no significant difference, including the bilateral posterior limb of the internal capsule, external capsule, sagittal striatum, fornix, and uncinate fasciculus.

CONCLUSIONS

We found differences in spatial distribution of abnormality in fractional anisotropy, isotropic volume fraction, and myelin volume fraction distribution in MS, which might be useful for characterizing white matter in patients with MS.

Preferences for health information in middle-aged Japanese workers based on health literacy levels: a descriptive study

OBJECTIVES

To describe the health information preferences in middle-aged Japanese workers based on health literacy (HL) levels and presence of medications.

STUDY DESIGN

A cross-sectional study.

METHODS

We performed a web-based questionnaire survey with Japanese workers aged below 60 years. HL was assessed using the total score of communicative skills (five items) and critical skills (four items) from the 14-item Health Literacy Scale. Regarding their health information preferences, participants were asked about the health information they wanted (four items), could easily understand (six items), or easily use (two items) and answered on a 4-point scale (strongly agree/agree/disagree/strongly disagree). The percentages of the affirmative responses (strongly agree or agree) were compared among tertiles based on the HL score.

RESULTS

We obtained data from a total of 3387 volunteers, of whom 510 participants were on either antihypertensive, lipid-lowering, or antidiabetic drugs. Compared with the high HL and middle HL groups, low HL had fewer affirmative responses to most health information items. Health information items received 70% of affirmative responses even in the low HL level. They were visually shown by figures or pictures, highlighted by colors for important points, could be read in 1-2 min, and were accessed on the Internet, regardless of the presence of medications. Additionally, the explanation for mechanisms of medications or lifestyle to prevent or improve diseases showed high affinity in all HL levels, only for those on medications.

CONCLUSIONS

This result generates a hypothesis that low HL individuals have a low interest in health information. Our data showed several possible forms of health information with high affinity based on HL levels that would help plan future population approaches.

Neuromelanin or DaT-SPECT: which is the better marker for discriminating advanced Parkinson's disease?

Background and purpose

Whether the neuromelanin‐positive substantia nigra pars compacta area (NM‐SNc) on neuromelanin magnetic resonance imaging (NM‐MRI) and the specific binding ratio (SBR) on ¹²³I‐N‐v‐fluoropropyl‐2b‐carbomethoxy3b‐(4‐iodophenyl)nortropane single photon emission computed tomography (DaT‐SPECT) can be correlated with motor fluctuations (MFs) in advanced Parkinson's disease (PD) was investigated.

Methods

Thirty‐five PD patients (60 ± 13 years) and 23 healthy individuals as controls (59 ± 19 years) were enrolled. The relationships between NM‐MRI and DaT‐SPECT were prospectively examined in two subgroups divided according to the presence or absence of MFs. Multivariate analysis was performed using the Cox proportional hazard model to screen for association factors.

Results

The NM‐SNc size was correlated with the SBR (Spearman's ρ = 0.43, P < 0.05). The NM‐SNc size was significantly reduced in PD with MFs compared with the subgroup without (P < 0.001), whereas the SBR did not significantly differ between the groups. NM‐SNc size was a significant association factor for MFs (hazard ratio 0.94, P = 0.04). In receiver operating characteristic analysis of the factors for MF occurrence, the area under the receiver operating characteristic curve of the NM‐SNc size showed a significant difference of 0.89 (P < 0.05) but no significant difference was found in the SBR.

Conclusions

NM‐SNc size was significantly correlated with the SBR in PD, but several factors in advanced PD were more closely associated with NM‐SNc size than the SBR. NM‐MRI might reflect the status of advanced PD more accurately than DaT‐SPECT. Therefore, NM‐MRI appears to provide a better marker for discriminating advanced PD than DaT‐SPECT.

Effect of Gadolinium on the Estimation of Myelin and Brain Tissue Volumes Based on Quantitative Synthetic MRI

BACKGROUND AND PURPOSE

The effect of gadolinium on the estimation of myelin has not been reported. The aim of the current study was to investigate the effects of gadolinium on automatic myelin and brain tissue volumetry via quantitative synthetic MR imaging.

MATERIALS AND METHODS

The study included 36 patients who were referred for brain metastases screening, and quantitative synthetic MR imaging data before and after gadolinium-based contrast agent administration were analyzed retrospectively. Brain metastases were detected in 17 patients. WM volume, GM volume, CSF volume, non-WM/GM/CSF volume, myelin volume, brain parenchymal volume, myelin fraction (myelin volume/brain parenchymal volume), and intracranial volume were estimated. T1 and T2 relaxation times, proton density, and myelin partial volume per voxel averaged across the brain parenchyma were also analyzed.

RESULTS

In patients with and without metastases after gadolinium-based contrast agent administration, measurements of WM and myelin volumes, and myelin fraction were significantly increased (+26.65 and +29.42 mL, +10.14 and +12.46 mL, +0.88% and +1.09%, respectively), whereas measurements of GM, CSF, brain parenchymal, and intracranial volumes were significantly decreased (-36.23 and -34.49 mL, -20.77 and -18.94 mL, -6.76 and -2.84 mL, -27.41 and -21.84 mL, respectively). Non-WM/GM/CSF volume did not show a significant change. T1, T2, and proton density were significantly decreased (-51.34 and -46.84 ms, -2.67 and -4.70 ms, -1.05%, and -1.28%, respectively) after gadolinium-based contrast agent administration, whereas measurements of myelin partial volume were significantly increased (+0.78% and +0.75%, respectively).

CONCLUSIONS

Gadolinium had a significant effect on the automatic calculation of myelin and brain tissue volumes using quantitative synthetic MR imaging, which can be explained by decreases in T1, T2, and proton density.

Improving the Quality of Synthetic FLAIR Images with Deep Learning Using a Conditional Generative Adversarial Network for Pixel-by-Pixel Image Translation

BACKGROUND AND PURPOSE

Synthetic FLAIR images are of lower quality than conventional FLAIR images. Here, we aimed to improve the synthetic FLAIR image quality using deep learning with pixel-by-pixel translation through conditional generative adversarial network training.

MATERIALS AND METHODS

Forty patients with MS were prospectively included and scanned (3T) to acquire synthetic MR imaging and conventional FLAIR images. Synthetic FLAIR images were created with the SyMRI software. Acquired data were divided into 30 training and 10 test datasets. A conditional generative adversarial network was trained to generate improved FLAIR images from raw synthetic MR imaging data using conventional FLAIR images as targets. The peak signal-to-noise ratio, normalized root mean square error, and the Dice index of MS lesion maps were calculated for synthetic and deep learning FLAIR images against conventional FLAIR images, respectively. Lesion conspicuity and the existence of artifacts were visually assessed.

RESULTS

The peak signal-to-noise ratio and normalized root mean square error were significantly higher and lower, respectively, in generated-versus-synthetic FLAIR images in aggregate intracranial tissues and all tissue segments (all P < .001). The Dice index of lesion maps and visual lesion conspicuity were comparable between generated and synthetic FLAIR images (P = 1 and .59, respectively). Generated FLAIR images showed fewer granular artifacts (P = .003) and swelling artifacts (in all cases) than synthetic FLAIR images.

CONCLUSIONS

Using deep learning, we improved the synthetic FLAIR image quality by generating FLAIR images that have contrast closer to that of conventional FLAIR images and fewer granular and swelling artifacts, while preserving the lesion contrast.

Imaging Differences between Neuromyelitis Optica Spectrum Disorders and Multiple Sclerosis: A Multi-Institutional Study in Japan

BACKGROUND AND PURPOSE

Both clinical and imaging criteria must be met to diagnose neuromyelitis optica spectrum disorders and multiple sclerosis. However, neuromyelitis optica spectrum disorders are often misdiagnosed as MS because of an overlap in MR imaging features. The purpose of this study was to confirm imaging differences between neuromyelitis optica spectrum disorders and MS with visually detailed quantitative analyses of large-sample data.

MATERIALS AND METHODS

We retrospectively examined 89 consecutive patients with neuromyelitis optica spectrum disorders (median age, 51 years; range, 16-85 years; females, 77; aquaporin 4 immunoglobulin G-positive, 93%) and 89 with MS (median age, 36 years; range, 18-67 years; females, 68; relapsing-remitting MS, 89%; primary-progressive MS, 7%; secondary-progressive MS, 2%) from 9 institutions across Japan (April 2008 to December 2012). Two neuroradiologists visually evaluated the number, location, and size of all lesions using the Mann-Whitney U test or the Fisher exact test.

RESULTS

We enrolled 79 patients with neuromyelitis optica spectrum disorders and 87 with MS for brain analysis, 57 with neuromyelitis optica spectrum disorders and 55 with MS for spinal cord analysis, and 42 with neuromyelitis optica spectrum disorders and 14 with MS for optic nerve analysis. We identified 911 brain lesions in neuromyelitis optica spectrum disorders, 1659 brain lesions in MS, 86 spinal cord lesions in neuromyelitis optica spectrum disorders, and 102 spinal cord lesions in MS. The frequencies of periventricular white matter and deep white matter lesions were 17% and 68% in neuromyelitis optica spectrum disorders versus 41% and 42% in MS, respectively (location of brain lesions, P < .001). We found a significant difference in the distribution of spinal cord lesions between these 2 diseases (P = .024): More thoracic lesions than cervical lesions were present in neuromyelitis optica spectrum disorders (cervical versus thoracic, 29% versus 71%), whereas they were equally distributed in MS (46% versus 54%). Furthermore, thoracic lesions were significantly longer than cervical lesions in neuromyelitis optica spectrum disorders (P = .001), but not in MS (P = .80).

CONCLUSIONS

Visually detailed quantitative analyses confirmed imaging differences, especially in brain and spinal cord lesions, between neuromyelitis optica spectrum disorders and MS. These observations may have clinical implications.

Disruption of the pacemaker activity of interstitial cells of Cajal via nitric oxide contributes to postoperative ileus

BACKGROUND

Interstitial cells of Cajal (ICC) serve as intestinal pacemakers. Postoperative ileus (POI) is a gastrointestinal motility disorder that occurs following abdominal surgery, which is caused by inflammation-induced dysfunction of smooth muscles and enteric neurons. However, the participation of ICC in POI is not well understood. In this study, we investigated the functional changes of ICC in a mouse model of POI.

METHODS

Intestinal manipulation (IM) was performed to induce POI. At 24 h or 48 h after IM, the field potential of the intestinal tunica muscularis was investigated. Tissues were also examined by immunohistochemistry and electron microscopic analysis.

KEY RESULTS

Gastrointestinal transit was significantly decreased with intestinal tunica muscularis inflammation at 24 h after IM, which was ameliorated at 48 h after IM. The generation and propagation of pacemaker potentials were disrupted at 24 h after IM and recovered to the control level at 48 h after IM. ICC networks, detected by c-Kit immunoreactivity, were remarkably disrupted at 24 h after IM. Electron microscopic analysis revealed abnormal vacuoles in the ICC cytoplasm. Interestingly, the ICC networks recovered at 48 h after IM. Administration of aminoguanidine, an inducible nitric oxide synthase inhibitor, suppressed the disruption of ICC networks. Ileal smooth muscle tissue cultured in the presence of nitric oxide donor, showed disrupted ICC networks.

CONCLUSIONS AND INFERENCES

The generation and propagation of pacemaker potentials by ICC are disrupted via nitric oxide after IM, and this disruption may contribute to POI. When inflammation is ameliorated, ICC can recover their pacemaker function.

Experimental technique for antiproton-nucleus annihilation cross section measurements at low energy

The interaction of very low energy antiprotons (ps) and antineutrons (ns) with nuclei is interesting for its influence on both fundamental cosmology and nuclear physics. Measuring the annihilation cross section of antimatter on matter can help in solving the universe matter-antimatter puzzle and could give relevant hints in the definition of strong interaction model parameters as well. The ASACUSA collaboration recently measured the antiproton-carbon annihilation cross section at 5.3 MeV of kinetic energy of the incoming antiproton. The experimental apparatus consisted in a vacuum chamber containing thin foils (~0.7-1 μm) of carbon crossed by a bunched beam of antiprotons from the CERN Antiproton Decelerator (AD). The fraction of antiprotons annihilating on the target nucleons gives origin to charged pions which can be detected and counted by segmented scintillators placed outside the chamber. This work describes the experimental details of the apparatus and the technique to perform the cross section measurements.

Antiproton-nucleus annihilation cross section at low energy

The antinucleon-nuclei annihilation cross sections at low energies were systematically measured at CERN in the 80’s and 90’s with the LEAR facility and later with the Antiproton Decelerator. Unfortunately only few data exist for very low energy antiprotons (p<500 MeV/c) on medium and heavy nuclei. A deeper knowledge is required by fundamental physics and can have consequence also in cosmology and medical physics. In order to fill the gap, the ASACUSA Collaboration has very recently measured the annihilation cross section of 100 MeV/c antiprotons on carbon. In the present work the experimental result is presented together with a comparison both with the antineutron data on the same target at the same energies and with the other existing antiproton data at higher energies.

Zingiberis Siccatum Rhizoma, the active component of the Kampo formula Daikenchuto, induces anti-inflammatory actions through α7 nicotinic acetylcholine receptor activation

BACKGROUND

We previously reported that Daikenchuto (DKT), a gastrointestinal prokinetic Japanese herbal (Kampo) medicine used for the treatment of postoperative ileus (POI), has characteristic potent anti-inflammatory activity. This effect may be partly mediated by the activation of α7 nicotinic acetylcholine receptor (nAChR). In this study, we identified the specific herbs in DKT that induce anti-inflammatory action.

METHODS

The herbal components of DKT were individually administered orally to each mouse four times before and after intestinal manipulation (IM) was carried out on the distal ileum. The anti-inflammatory activity of each crude drug was subsequently evaluated using immunohistochemical analyses of relevant molecules.

KEY RESULTS

Treatment with Zingiberis Siccatum Rhizoma (ZSR) but not the other components inhibited the infiltration of cluster of differentiation 68 (CD68)-positive macrophages as effectively as DKT treatment. Selective α7nAChR antagonists, such as methyllycaconitine citrate, or transient receptor potential ankyrin 1 (TRPA1) antagonists, such as HC-030031, significantly inhibited the amelioration of macrophage infiltration by ZSR. The inhibition of macrophage infiltration by ZSR was abolished in both α7nAChR and 5-hydroxytryptamine 4 receptor (5-HT₄ R) knockout mice.

CONCLUSIONS & INFERENCES

Daikenchuto-induced anti-inflammatory activity, which was mediated by inhibiting macrophage infiltration in POI, is dependent on the effects of ZSR. Zingiberis Siccatum Rhizoma activates TRPA1 channels possibly in enterochromaffin (EC) cells to release 5-HT, which stimulates 5-HT₄ R in the myenteric plexus neurons to release ACh, which in turn activates α7nAChR on macrophages to inhibit inflammation in POI.

Blue light-induced immunosuppression in Bactrocera dorsalis adults, as a carryover effect of larval exposure

Detrimental effects of ultraviolet (UV) light on living organisms are well understood, little is known about the effects of blue light irradiation. Although a recent study revealed that blue light caused more harmful effects on insects than UV light and blue light irradiation killed insect pests of various orders including Diptera, the effects of blue light on physiology of insects are still largely unknown. Here we studied the effects of blue light irradiation on cuticular melanin in larval and the immune response in adult stage of Bactrocera dorsalis. We also evaluated the effects of blue light exposure in larval stage on various age and mass at metamorphosis and the mediatory role of cuticular melanin in carryover effects of larval stressors across metamorphosis. We found that larvae exposed to blue light decreased melanin contents in their exoskeleton with smaller mass and delayed metamorphosis than insects reared without blue light exposure. Across metamorphosis, lower melanotic encapsulation response and higher susceptibility to Beauveria bassiana was detected in adults that had been exposed to blue light at their larval stage, thereby constituting the first evidence that blue light impaired adult immune function in B. dorsalis as a carryover effect of larval exposure.

Automated brain tissue and myelin volumetry based on quantitative MR imaging with various in-plane resolutions

BACKGROUND AND PURPOSE

Segmented brain tissue and myelin volumes can now be automatically calculated using dedicated software (SyMRI), which is based on quantification of R₁ and R₂ relaxation rates and proton density. The aim of this study was to determine the validity of SyMRI brain tissue and myelin volumetry using various in-plane resolutions.

METHODS

We scanned 10 healthy subjects on a 1.5T MR scanner with in-plane resolutions of 0.8, 2.0 and 3.0mm. Two scans were performed for each resolution. The acquisition time was 7-min and 24-sec for 0.8mm, 3-min and 9-sec for 2.0mm and 1-min and 56-sec for 3.0mm resolutions. The volumes of white matter (WM), gray matter (GM), cerebrospinal fluid (CSF), non-WM/GM/CSF (NoN), brain parenchymal volume (BPV), intracranial volume (ICV) and myelin were compared between in-plane resolutions. Repeatability for each resolution was then analyzed.

RESULTS

No significant differences in volumes measured were found between the different in-plane resolutions, except for NoN between 0.8mm and 2.0mm and between 2.0mm and 3.0mm. The repeatability error value for the WM, GM, CSF, NoN, BPV and myelin volumes relative to ICV was 0.97%, 1.01%, 0.65%, 0.86%, 1.06% and 0.25% in 0.8mm; 1.22%, 1.36%, 0.73%, 0.37%, 1.18% and 0.35% in 2.0mm and 1.18%, 1.02%, 0.96%, 0.45%, 1.36%, and 0.28% in 3.0mm resolutions.

CONCLUSION

SyMRI brain tissue and myelin volumetry with low in-plane resolution and short acquisition times is robust and has a good repeatability so could be useful for follow-up studies.

Analysis of White Matter Damage in Patients with Multiple Sclerosis via a Novel In Vivo MR Method for Measuring Myelin, Axons, and G-Ratio

BACKGROUND AND PURPOSE

Myelin and axon volume fractions can now be estimated via MR imaging in vivo, as can the g-ratio, which equals the ratio of the inner to the outer diameter of a nerve fiber. The purpose of this study was to evaluate WM damage in patients with MS via this novel MR imaging technique.

MATERIALS AND METHODS

Twenty patients with relapsing-remitting MS with a combined total of 149 chronic plaques were analyzed. Myelin volume fraction was calculated based on simultaneous tissue relaxometry. Intracellular and CSF compartment volume fractions were quantified via neurite orientation dispersion and density imaging. Axon volume fraction and g-ratio were calculated by combining these measurements. Myelin and axon volume fractions and g-ratio were measured in plaques, periplaque WM, and normal-appearing WM.

RESULTS

All metrics differed significantly across the 3 groups (P < .001, except P = .027 for g-ratio between periplaque WM and normal-appearing WM). Those in plaques differed most from those in normal-appearing WM. The percentage changes in plaque and periplaque WM metrics relative to normal-appearing WM were significantly larger in absolute value for myelin volume fraction than for axon volume fraction and g-ratio (P < .001, except P = .033 in periplaque WM relative to normal-appearing WM for comparison between myelin and axon volume fraction).

CONCLUSIONS

In this in vivo MR imaging study, the myelin of WM was more damaged than axons in plaques and periplaque WM of patients with MS. Myelin and axon volume fractions and g-ratio may potentially be useful for evaluating WM damage in patients with MS.

First Elastic Electron Scattering from ^{132}Xe at the SCRIT Facility

The first elastic electron scattering has been successfully performed at the self-confining radioactive-isotope ion target (SCRIT) facility, the world's first electron scattering facility for SCRIT technique achieved high luminosity (over 10^{27}  cm^{-2} s^{-1}, sufficient for determining the nuclear shape) with only 10^{8} target ions. While ^{132}Xe used in this time as a target is a stable isotope, the charge density distribution was first extracted from the momentum transfer distributions of the scattered electrons by comparing the results with those calculated by a phase shift calculation.

Non-Contrast-Enhanced Silent Scan MR Angiography of Intracranial Anterior Circulation Aneurysms Treated with a Low-Profile Visualized Intraluminal Support Device

BACKGROUND AND PURPOSE

The Low-Profile Visualized Intraluminal Support Device comprises a small-cell nitinol structure and a single-wire braided stent that provides greater metal coverage than previously reported intracranial stents, as well as assumed strong susceptibility artifacts. This study aimed to assess the benefits of non-contrast-enhanced MRA by using a Silent Scan (Silent MRA) for intracranial anterior circulation aneurysms treated with Low-Profile Visualized Intraluminal Support Device stents.

MATERIALS AND METHODS

Thirty-one aneurysms treated with Low-Profile Visualized Intraluminal Support Device stents were assessed by using Silent MRA, 3D TOF-MRA, and x-ray DSA. The quality of MRA visualization of the reconstructed artery was graded on a 4-point scale from 1 (not visible) to 4 (excellent). Aneurysm occlusion status was evaluated by using a 2-grade scale (total occlusion/remnant [neck or aneurysm]). Weighted κ statistics were used to evaluate interobserver and intermodality agreement.

RESULTS

The mean scores ± SDs for Silent MRA and 3D TOF-MRA were 3.16 ± 0.79 and 1.48 ± 0.67 (P < .05), respectively, with substantial interobserver agreement (κ = 0.66). The aneurysm occlusion rates of the 2-grade scale (total occlusion/remnant [neck or aneurysm]) were 69%/31% for DSA, 65%/35% for Silent MRA, and 92%/8% for 3D TOF-MRA, respectively. The intermodality agreements were 0.88 and 0.30 for DSA/Silent MRA and DSA/3D TOF-MRA, respectively.

CONCLUSIONS

Silent MRA seems to be useful for visualizing intracranial anterior circulation aneurysms treated with Low-Profile Visualized Intraluminal Support Device stents.

Usefulness of Non-Contrast-Enhanced MR Angiography Using a Silent Scan for Follow-Up after Y-Configuration Stent-Assisted Coil Embolization for Basilar Tip Aneurysms

BACKGROUND AND PURPOSE

Y-configuration stent-assisted coil embolization is used for treating wide-neck aneurysms. Noninvasive alternatives to x-ray DSA for follow-up after Y-configuration stent-assisted coil embolization treatment are required. This study aimed to assess the usefulness of non-contrast-enhanced MRA by using a Silent Scan (silent MRA) for follow-up after Y-configuration stent-assisted coil embolization for basilar tip aneurysms.

MATERIALS AND METHODS

Seven patients treated with Y-configuration stent-assisted coil embolization for basilar tip aneurysms underwent silent MRA, 3D TOF-MRA, and DSA. Silent MRA and 3D TOF-MRA images were obtained during the same scan session on a 3T MR imaging system. Two neuroradiologists independently reviewed both types of MRA images and subjectively scored the flow in the stents on a scale of 1 (not visible) to 5 (nearly equal to DSA) by referring to the latest DSA image as a criterion standard. Furthermore, we evaluated the visualization of the neck remnant.

RESULTS

In all patients, the 2 observers gave a higher score for the flow in the stents on silent MRA than on 3D TOF-MRA. The average score ± standard deviation was 4.07 ± 0.70 for silent MRA and 1.93 ± 0.80 (P < .05) for 3D TOF-MRA. Neck remnants were depicted by DSA in 5 patients. In silent MRA, neck remnants were depicted in 5 patients, and visualization was similar to DSA; however, in 3D TOF-MRA, neck remnants were depicted in only 1 patient.

CONCLUSIONS

Silent MRA might be useful for follow-up after Y-configuration stent-assisted coil embolization.

Synthetic MRI in the Detection of Multiple Sclerosis Plaques

BACKGROUND AND PURPOSE

Synthetic MR imaging enables the creation of various contrast-weighted images including double inversion recovery and phase-sensitive inversion recovery from a single MR imaging quantification scan. Here, we assessed whether synthetic MR imaging is suitable for detecting MS plaques.

MATERIALS AND METHODS

Quantitative and conventional MR imaging data on 12 patients with MS were retrospectively analyzed. Synthetic T2-weighted, FLAIR, double inversion recovery, and phase-sensitive inversion recovery images were produced after quantification of T1 and T2 values and proton density. Double inversion recovery images were optimized for each patient by adjusting the TI. The number of visible plaques was determined by a radiologist for a set of these 4 types of synthetic MR images and a set of conventional T1-weighted inversion recovery, T2-weighted, and FLAIR images. Conventional 3D double inversion recovery and other available images were used as the criterion standard. The total acquisition time of synthetic MR imaging was 7 minutes 12 seconds and that of conventional MR imaging was 6 minutes 29 seconds The lesion-to-WM contrast and lesion-to-WM contrast-to-noise ratio were calculated and compared between synthetic and conventional double inversion recovery images.

RESULTS

The total plaques detected by synthetic and conventional MR images were 157 and 139, respectively (P = .014). The lesion-to-WM contrast and contrast-to-noise ratio on synthetic double inversion recovery images were superior to those on conventional double inversion recovery images (P = .001 and < 0.001, respectively).

CONCLUSIONS

Synthetic MR imaging enabled detection of more MS plaques than conventional MR imaging in a comparable acquisition time. The contrast for MS plaques on synthetic double inversion recovery images was better than on conventional double inversion recovery images.

Utility of a Multiparametric Quantitative MRI Model That Assesses Myelin and Edema for Evaluating Plaques, Periplaque White Matter, and Normal-Appearing White Matter in Patients with Multiple Sclerosis: A Feasibility Study

BACKGROUND AND PURPOSE

T1 and T2 values and proton density can now be quantified on the basis of a single MR acquisition. The myelin and edema in a voxel can also be estimated from these values. The purpose of this study was to evaluate a multiparametric quantitative MR imaging model that assesses myelin and edema for characterizing plaques, periplaque white matter, and normal-appearing white matter in patients with MS.

MATERIALS AND METHODS

We examined 3T quantitative MR imaging data from 21 patients with MS. The myelin partial volume, excess parenchymal water partial volume, the inverse of T1 and transverse T2 relaxation times (R1, R2), and proton density were compared among plaques, periplaque white matter, and normal-appearing white matter.

RESULTS

All metrics differed significantly across the 3 groups (P < .001). Those in plaques differed most from those in normal-appearing white matter. The percentage changes of the metrics in plaques and periplaque white matter relative to normal-appearing white matter were significantly more different from zero for myelin partial volume (mean, -61.59 ± 20.28% [plaque relative to normal-appearing white matter], and mean, -10.51 ± 11.41% [periplaque white matter relative to normal-appearing white matter]), and excess parenchymal water partial volume (13.82 × 10³ ± 49.47 × 10³% and 51.33 × 10² ± 155.31 × 10²%) than for R1 (-35.23 ± 13.93% and -6.08 ± 8.66%), R2 (-21.06 ± 11.39% and -4.79 ± 6.79%), and proton density (23.37 ± 10.30% and 3.37 ± 4.24%).

CONCLUSIONS

Multiparametric quantitative MR imaging captures white matter damage in MS. Myelin partial volume and excess parenchymal water partial volume are more sensitive to the MS disease process than R1, R2, and proton density.

Multishot Echo-Planar Imaging with Gadopentetate Dimeglumine: Preliminary study of efficacy for detection of hypovascular metastatic liver tumors

Objective: To evaluate the usefulness of sequential T2-weighted spin-echo type multishot echo-planar (T2-EP) imaging with gadopentetate dimeglumine for the detection of hypovascular metastatic liver tumors.

Material and Methods: Fifteen consecutive patients with 56 proven hypovascular metastatic liver tumors were included in the study. Three observers blindly and independently read the whole-liver images obtained with T2-weighted spin-echo, T2-weighted single-shot fast spin-echo, T1-weighted fast multiplanar spoiled GRASS and T2-EP images obtained before and 25, 60, 90 and 120 s after injection of 0.2 mmol/kg b.w. of gadopentetate dimeglumine. The diagnostic accuracy was estimated by calculating the area under the observer-specific binomial receiver operating characteristics curves (Az).

Results: T2-EP images obtained 60 s after contrast injection showed significantly higher contrast-to-noise (C/N) ratios than the other imaging techniques. A combination of all phases of the T2-EP images produced the highest sensitivity and specificity. In terms of the Az value, the diagnostic accuracy for tumor detection achieved with a combination of all phases of the T2-EP images was significantly higher than that with T1-SPGR and T2-SSFSE images ( p < 0.01). The Az values of the T2-EP images (Az = 0.975) were higher than those of T2-CSE images (Az = 0.948), but the difference was not significant.

Conclusion: Our preliminary study revealed that sequential imaging with enhanced T2-EP images was useful for the detection of hypovascular metastatic liver tumors because of its superior C/N ratio and sensitivity.

Epidermal growth factor is a critical regulator of the cytokine IL-33 in intestinal epithelial cells

BACKGROUND AND PURPOSE

IL-33 is a novel cytokine that is believed to be involved in inflammation and carcinogenesis. However, its source, its production and its secretion process remain unclear. Recently, we have reported that IL-33 is up-regulated in dextran sulfate sodium (DSS) colitis in mice.

EXPERIMENTAL APPROACH

Production of IL-33 from intestinal tissue was studied in a murine cancer model induced by azoxymethane (AOM) and DSS in vivo and in cultures of IEC-6 epithelial cells. Cytokine levels were measured by real time PCR, immunohistochemistry and elisa.

KEY RESULTS

Mice with AOM/DSS-induced colitis expressed all the characteristic symptoms of colon cancer pathology. Immunohistochemical analysis demonstrated epithelial cell-derived IL-33 in colon tissues from mice with AOM/DSS colitis. Real time PCR and quantitative PCR analysis revealed that AOM/DSS colitis tissues expressed up-regulated IL-1β, IL-33, TGF-β, and EGF mRNA. Gefitinib, an EGFR inhibitor, inhibited IL-33 mRNA expression in AOM/DSS colitis mice. The pathophysiological role of IL-33 in the rat intestinal epithelial cell line (IEC-6 cells) was then investigated. We found that EGF, but not TGF-β1 or PDGF, greatly enhanced mRNA expression of IL-33 and its receptor ST2. In accordance with the gene expression and immunohistochemical analysis of IL-33 levels, elisa-based analysis of cytoplasmic and nuclear extracts showed increased IL-33 protein levels in IEC-6 cells after treatment with EGF.

CONCLUSIONS AND IMPLICATIONS

Our results suggest that EGF is a key growth factor that increased IL-33 production and ST2 receptor expression during intestinal inflammation and carcinogenesis. The EGF/IL-33/ST2 axis represents a novel therapeutic target in colon cancer.

The role of plasma chemistry on functional silicon nitride film properties deposited at low-temperature by mixing two frequency powers using PECVD

A correlation study of plasma parameters and film properties and the implication of dual frequency PECVD for industry are proposed.

High sensitivity of a carbon nanowall-based sensor for detection of organic vapours

The high sensitivity in response, selectivity and reversibility was achieved on a carbon nanowall-based sensor for the vapor detection of volatile organic compounds, which were tested by an electrical resistance method during adsorption and desorption cycles.

Assessing Blood Flow in an Intracranial Stent: A Feasibility Study of MR Angiography Using a Silent Scan after Stent-Assisted Coil Embolization for Anterior Circulation Aneurysms

BACKGROUND AND PURPOSE

Blood flow in an intracranial stent cannot be visualized with 3D time-of-flight MR angiography owing to magnetic susceptibility and radiofrequency shielding. As a novel follow-up tool after stent-assisted coil embolization, we applied MRA by using a Silent Scan algorithm that contains an ultrashort TE combined with an arterial spin-labeling technique (Silent MRA). The purpose of this study was to determine whether Silent MRA could visualize flow in an intracranial stent placed in the anterior circulation.

MATERIALS AND METHODS

Nine patients treated with stent-assisted coil embolization for anterior circulation aneurysms underwent MRAs (Silent MRA and TOF MRA) and x-ray digital subtraction angiography. MRAs were performed in the same session on a 3T unit. Two neuroradiologists independently reviewed the MRA images and subjectively scored flow in a stent as 1 (not visible) to 4 (excellent) by referring to the latest x-ray digital subtraction angiography image as a criterion standard.

RESULTS

Both observers gave MRA higher scores than TOF MRA for flow in a stent in all cases. The mean score for Silent MRA was 3.44 ± 0.53, and for TOF MRA, it was 1.44 ± 0.46 (P < .001).

CONCLUSIONS

Silent MRA was able to visualize flow in an intracranial stent more effectively than TOF MRA. Silent MRA might be useful for follow-up imaging after stent-assisted coil embolization, though these study results may be only preliminary due to some limitations.

Multiple roles of the PGE2 -EP receptor signal in vascular permeability

BACKGROUND AND PURPOSE

PGE2 is a major prostanoid that regulates inflammation by stimulating EP1-4 receptors. However, how PGE2 induces an initial inflammatory response to vascular hyper-permeability remains unknown. Here we investigated the role of the PGE2 -EP receptor signal in modulating vascular permeability both in vivo and in vitro.

EXPERIMENTAL APPROACH

We used a modified Miles assay and intravital microscopy to examine vascular permeability in vivo. Endothelial barrier property was assessed by measuring transendothelial electrical resistance (TER) in vitro.

KEY RESULTS

Local administration of PGE2 , an EP2 or EP4 receptor agonist into FVB/NJcl mouse ear skin caused vascular leakage, indicated by dye extravasation. Intravital microscopy and laser Doppler blood-flow imaging revealed that these treatments dilated peripheral vessels and increased local blood flow. Pretreatment with the vasoconstrictor phenylephrine inhibited the PGE2 -induced blood flow increase and vascular leakage. In contrast to the EP2 and EP4 receptor agonists, administration of an EP3 receptor agonist suppressed vascular leakage without altering vascular diameter or blood flow. In isolated HUVECs, the EP3 receptor agonist elevated TER and blocked thrombin-induced dextran passage. Inhibiting PKA restored the hypo-permeability induced by the EP3 receptor agonist.

CONCLUSIONS AND IMPLICATIONS

Activation of the PGE2 -EP2 or -EP4 receptor signal induces vasodilatation in mural cells, resulting in increased local blood flow and hyper-permeability. In contrast, activation of the PGE2 -EP3 receptor signal induces a cAMP-dependent enhancement of the endothelial barrier, leading to hypo-permeability. We provide the first evidence that endothelial cells and mural cells cooperate to modulate vascular permeability.

PDGF and TGF-β promote tenascin-C expression in subepithelial myofibroblasts and contribute to intestinal mucosal protection in mice

BACKGROUND AND PURPOSE

Tenascin-C (TnC) is a multi-domain extracellular matrix glycoprotein that is expressed at a high level during embryogenesis but is almost absent during normal postnatal life. This multi-domain complex molecule is reported to associate with both pro-inflammatory and anti-inflammatory signalling cascades. In this study, we examined how TnC modulated intestinal inflammation.

EXPERIMENTAL APPROACH

TnC pathophysiology was evaluated in cultures of rat intestinal subepithelial myofibroblasts (ISEMF) and intestinal epithelial cells. Wild-type and TnC(-/-) mice were treated with dextran sodium sulfate (DSS) to induce colitis.

KEY RESULTS

DSS-induced colitis in mice markedly increased TnC in the damaged mucosal areas and up-regulated mRNA for TnC, pro-inflammatory cytokines and growth factors (PDGF-B and TGF-β1). In addition, 2,4,6-trinitrobenzene sulfonic acid-induced colitis and SAMP1/Yit mice, a model of spontaneous Crohn's disease, also exhibited increased mucosal TnC in colon and ilea respectively. PDGF receptor-α (PDGFRα) positive ISEMF were the primary TnC-producing cells in colon tissues. Accordingly, ISEMF collected from the rat colon constitutively expressed both TnC and PDGFRα. PDGF-BB and TGF-β1 up-regulated both TnC mRNA and protein levels in ISEMF. Knock-down of TnC gene increased susceptibility to DSS-induced colitis, compared with TnC(+/+) littermates. TnC(-/-) mice showed marked abrasion of intestinal mucosal barrier and increased inflammatory scores. Moreover, TnC accelerated both trans-well migration and wound healing in epithelial cells.

CONCLUSIONS AND IMPLICATIONS

The pharmacological profiles of PDGF-BB and TGF-β in colitis tissues and ISEMF suggest that increased TnC production during inflammation contributed to epithelial cell migration, remodelling and protection of intestinal barriers.

Laparoscopic intraoperative navigation surgery for gastric cancer using real-time rendered 3D CT images

PURPOSE

Recent advances in laparoscopic surgical technology have made it possible to perform advanced high-level surgery, such as lymph node dissection for malignancy. Grasping the anatomy during such procedures is important for a safe operation. We have developed a new image information system that provides three-dimensional (3D) reconstructed CT images synchronized with the motion of the laparoscope. This study assesses this new navigation system.

METHODS

Enhanced CT using a custom-made software program can provide 3D angiography images reconstructed as a laparoscopic view. A motion sensor mounted on the laparoscope can detect the direction angle of the laparoscope. The real-time rendered 3D CT images are synchronized with the laparoscopic video images according to the motion of the scope. These 3D CT images are projected on another monitor close to the laparoscopic video monitor. Lymph node dissection can be performed with the help of the real-time navigation system that provides a detailed 3D view of the vasculature.

RESULTS

Ten laparoscopic gastrectomies were performed using this navigation system. Real-time intraoperative navigation of the vasculature was available, allowing for an excellent surgical outcome. No complications occurred in this series.

CONCLUSION

Our intraoperative navigation system allows for safe laparoscopic gastric lymph node dissection.